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Sample records for induced pressure waves

  1. Wave-Induced Pressure Under an Internal Solitary Wave and Its Impact at the Bed

    NASA Astrophysics Data System (ADS)

    Rivera, G.; Diamessis, P.; Jenkins, J.

    2016-02-01

    Internal Solitary Waves (ISW) of depression are known to cause significant resuspension and bed deformation during their passage. The underlying interplay between wave-driven hydrodynamics in the water column and the bed are yet to be fully understood. Given a characteristic stratification profile, observations of the induced-pressure hint at a potential bed failure during a wave episode. Employing a Fourier- nodal Galerkin method, we solve for the diffusion of the wave-induced pressure and assess the critical bed-normal pressure gradient responsible for particle movement. Likewise, we can also assess the induced shear stress as a possible mechanism for failure. In a similar context, we also examine the near-bed turbulent wake in the separating region in the lee of the wave. At sufficiently high ISW amplitude, the wave-induced BBL undergoes a global instability which produces intermittent vortex shedding from within the separation bubble. Using a 2D spectral multidomain penalty method with Re O(105), we resolve for the vortex shedding episode expanding the scope of the induced-pressure and shear stress and characterizing their subsequent development. It can be argued that the resuspension of bottom particulate upon the passage of the ISW trough and BBL separation directly relates to the potential for bed failure. We aim to link both events under the context of a specific sediment transport model capable of describing a range of ISW environments studied in the field.

  2. Influence of low pressure on laser inducing leaky Lamb wave and Scholte wave at air-solid interface

    NASA Astrophysics Data System (ADS)

    Yan, Zhao; Zhonghua, Shen; Jian, Lu; Xiaowu, Ni; Yiping, Cui

    2011-10-01

    A setup with Q-switched Nd:YAG laser inducing acoustic wave at air-solid interface and air-coupled optical deflection sensor was developed to research the influences of low air pressure on laser inducing leaky Lamb and Scholte waves at air-solid interface. The solid plate is settled in an airtight vessel abounded with standard air and its pressure can be adjusted by a vacuum pump. By experiments, the waveforms of laser induced interface acoustic waves, leaky Lamb and Scholte waves, under air pressures from 0.02 to 0.08 MPa with 0.01 MPa interval were first measured comprehensively. From the waveforms, we find that with increasing air pressure, the leaky energy of Lamb waves increase linearly and the amplitude of Scholte waves increase exponentially, but the velocity of Scholte waves decreases obviously.

  3. Utilization of sparker induced pressure waves to tenderize meat

    USDA-ARS?s Scientific Manuscript database

    This study investigated the feasibility of tenderizing meat using high pressure waves generated from a sparker source. Beef strip loins were cut into steaks from the anterior end and one to two steaks from each strip loin were randomly selected to serve as non-treated controls and the remaining ste...

  4. Pressure induced Superconductivity in the Charge Density Wave Compound Tritelluride

    SciTech Connect

    Hamlin, J.J.; Zocco, D.A.; Sayles, T.A.; Maple, M.B.; Chu, J.-H.; Fisher, I.R.; /Stanford U., Geballe Lab.

    2010-02-15

    A series of high-pressure electrical resistivity measurements on single crystals of TbTe{sub 3} reveal a complex phase diagram involving the interplay of superconducting, antiferromagnetic and charge density wave order. The onset of superconductivity reaches a maximum of almost 4 K (onset) near {approx} 12.4 GPa.

  5. Microwave-induced thermoelastic pressure wave propagation in the cat brain

    SciTech Connect

    Lin, J.C.; Su, J.L.; Wang, Y.

    1988-01-01

    This paper presents direct measurements of acoustic pressure wave propagation in cat brains irradiated with pulsed 2.45-GHz microwaves. Short rectangular microwave pulses (2 microseconds, 15 kW peak power) were applied singly through a direct-contact applicator located at the occipital pole of a cat's head. Acoustic pressure waves were detected by using a small hydrophone transducer, which was inserted stereotaxically into the brain of an anesthetized animal through a matrix of holes drilled on the skull. The measurements clearly indicate that pulsed microwaves induce acoustic pressure waves which propagate with an acoustic wave velocity of 1523 m/s.

  6. The pressure impulse of a laser-induced underwater shock wave

    NASA Astrophysics Data System (ADS)

    Tagawa, Yoshiyuki; Yamamoto, Shota; Hayasaka, Keisuke; Kameda, Masaharu

    2016-11-01

    We investigate the pressure impulse, the time integral of pressure evolution, of a laser-induced underwater shock wave. We simultaneously observe plasma formation, shock-wave expansion, and pressure in water using a combined measurement system that obtains high-resolution nanosecond-order image sequences. Remarkably, pressure impulse is found to distribute symmetrically for a wide range of experimental parameters even when the shock waves are emitted from an elongated plasma. In contrast, distribution of pressure peak is found to be non-spherically-symmetric. We rationalize aforementioned results by considering the structure of the underwater shock wave as a collection of multiple spherical shock waves originated from point-like plasmas in an elongated region. This work was supported by JSPS KAKANHI Grant Number JP26709007.

  7. A simplified physical model of pressure wave dynamics and acoustic wave generation induced by laser absorption in the retina.

    PubMed

    Till, S J; Milsom, P K; Rowlands, G

    2004-07-01

    Shock waves have been proposed in the literature as a mechanism for retinal damage induced by ultra-short laser pulses. For a spherical absorber, we derive a set of linear equations describing the propagation of pressure waves. We show that the formation of shock fronts is due to the form of the absorber rather than the inclusion of nonlinear terms in the equations. The analytical technique used avoids the need for a Laplace transform approach and is easily applied to other absorber profiles. Our analysis suggests that the 'soft' nature of the membrane surrounding retinal melanosomes precludes shock waves as a mechanism for the retinal damage induced by ultra-short pulse lasers. The quantitative estimates of the pressure gradients induced by laser absorption which are made possible by this work, together with detailed meso-scale or molecular modelling, will allow alternative damage mechanisms to be identified.

  8. Wave-induced pore pressure and effective stresses in a porous seabed with variable permeability

    SciTech Connect

    Jeng, D.S.; Seymour, B.R.

    1996-12-31

    An evaluation of wave-induced soil response is particularly useful for geotechnical and coastal engineers involved in the design of foundations for offshore structures. To simplify the mathematical procedure, most theories available for the wave/seabed interaction problem have assumed a porous seabed with uniform permeability, despite strong evidence of variable permeability. This paper proposes an analytical solution for the wave induced soil response in a porous seabed with variable permeability. Verification is available through reduction to the simple case of uniform permeability. The numerical results indicate that the effect of variable soil permeability on pore pressure and effective stresses is significant.

  9. Influence of ambient air pressure on the energy conversion of laser-breakdown induced blast waves

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Komurasaki, Kimiya; Arakawa, Yoshihiro

    2013-09-01

    Influence of ambient pressure on energy conversion efficiency from a Nd : glass laser pulse (λ = 1.053 µm) to a laser-induced blast wave was investigated at reduced pressure. Temporal incident and transmission power histories were measured using sets of energy meters and photodetectors. A half-shadowgraph half-self-emission method was applied to visualize laser absorption waves. Results show that the blast energy conversion efficiency ηbw decreased monotonically with the decrease in ambient pressure. The decrease was small, from 40% to 38%, for the pressure change from 101 kPa to 50 kPa, but the decrease was considerable, to 24%, when the pressure was reduced to 30 kPa. Compared with a TEA-CO2-laser-induced blast wave (λ = 10.6 µm), higher fraction absorption in the laser supported detonation regime ηLSD of 90% was observed, which is influenced slightly by the reduction of ambient pressure. The conversion fraction ηbw/ηLSD≈90% was achieved at pressure >50 kPa, which is significantly higher than that in a CO2 laser case.

  10. Underwater pressure amplification of laser-induced plasma shock waves for particle removal applications

    SciTech Connect

    Dunbar, Thomas J.; Cetinkaya, Cetin

    2007-07-30

    Underwater amplification of laser-induced plasma (LIP)-generated transient pressure waves using shock tubes is introduced and demonstrated. Previously, it has been shown that LIP for noncontact particle removal is possible on the sub-100-nm level. This is now enhanced through shock tube utilization in a medium such as water by substantially increasing shock wave pressure for the same pulse energy. A shock tube constrains the volume and changes the propagation direction of the expanding plasma core by focusing a pulsed-laser beam inside a tube with a blind end, thus increasing the wave front pressure generated. Current amplification approach can reduce radiation exposure of the substrate from the shock wave because of the increased distance from the LIP core to the substrate provided by the increased pressure per unit pulse energy. For the same pulsed laser, with the aid of a shock tube, substantial levels of pressure amplitude amplification (8.95) and maximum pressure (6.48 MPa) are observed and reported.

  11. An experimental study on the wave-induced pore water pressure change and relative influencing factors in the silty seabed

    NASA Astrophysics Data System (ADS)

    Li, Anlong; Luo, Xiaoqiao; Lin, Lin; Ye, Qing; Le, Chunyu

    2014-12-01

    In this study, a flume experiment was designed to investigate the characteristics of wave-induced pore water pressure in the soil of a silty seabed with different clay contents, soil layer buried depths and wave heights respectively. The study showed that water waves propagating over silty seabed can induce significant change of pore water pressure, and the amplitude of pore pressure depends on depth of buried soil layer, clay content and wave height, which are considered as the three influencing factors for pore water pressure change. The pressure will attenuate according to exponential law with increase of soil layer buried depth, and the attenuation being more rapid in those soil layers with higher clay content and greater wave height. The pore pressure in silty seabed increases rapidly in the initial stage of wave action, then decreases gradually to a stable value, depending on the depth of buried soil layer, clay content and wave height. The peak value of pore pressure will increase if clay content or depth of buried soil layer decreases, or wave height increases. The analysis indicated that these soils with 5% clay content and waves with higher wave height produce instability in bed easier, and that the wave energy is mostly dissipated near the surface of soils and 5% clay content in soils can prevent pore pressure from dissipating immediately.

  12. Shear wave measurements in shock-induced, high-pressure phases

    SciTech Connect

    Aidun, J.B.

    1993-01-01

    Structural phase transformations under shock loading are of considerable interest for understanding the response of solids under nonhydrostatic stresses and at high strain-rates. Examining shock-induced transformations from continuum level measurements is fundamentally constrained by the inability to directly identify microscopic processes, and also by the limited number of material properties that can be directly measured. ne latter limitation can be reduced by measuring both shear and compression waves using Lagrangian gauges in combined, compression and shear loading. The shear wave serves as an important, real-time probe of the shocked state and unloading response. Using results from a recent study of CaCO[sub 3], the unique information obtained from the shear wave speed and the detailed structure of the shear wave are shown to be useful for distinguishing the effects of phase transformations from yielding, as well as in characterizing the high-pressure phases and the yielding process under shock loading.

  13. Shear wave measurements in shock-induced, high-pressure phases

    SciTech Connect

    Aidun, J.B.

    1993-07-01

    Structural phase transformations under shock loading are of considerable interest for understanding the response of solids under nonhydrostatic stresses and at high strain-rates. Examining shock-induced transformations from continuum level measurements is fundamentally constrained by the inability to directly identify microscopic processes, and also by the limited number of material properties that can be directly measured. ne latter limitation can be reduced by measuring both shear and compression waves using Lagrangian gauges in combined, compression and shear loading. The shear wave serves as an important, real-time probe of the shocked state and unloading response. Using results from a recent study of CaCO{sub 3}, the unique information obtained from the shear wave speed and the detailed structure of the shear wave are shown to be useful for distinguishing the effects of phase transformations from yielding, as well as in characterizing the high-pressure phases and the yielding process under shock loading.

  14. Syrinx fluid transport: modeling pressure-wave-induced flux across the spinal pial membrane.

    PubMed

    Elliott, N S J

    2012-03-01

    Syrinxes are fluid-filled cavities of the spinal cord that characterize syringomyelia, a disease involving neurological damage. Their formation and expansion is poorly understood, which has hindered successful treatment. Syrinx cavities are hydraulically connected with the spinal subarachnoid space (SSS) enveloping the spinal cord via the cord interstitium and the network of perivascular spaces (PVSs), which surround blood vessels penetrating the pial membrane that is adherent to the cord surface. Since the spinal canal supports pressure wave propagation, it has been hypothesized that wave-induced fluid exchange across the pial membrane may play a role in syrinx filling. To investigate this conjecture a pair of one-dimensional (1-d) analytical models were developed from classical elastic tube theory coupled with Darcy's law for either perivascular or interstitial flow. The results show that transpial flux serves as a mechanism for damping pressure waves by alleviating hoop stress in the pial membrane. The timescale ratio over which viscous and inertial forces compete was explicitly determined, which predicts that dilated PVS, SSS flow obstructions, and a stiffer and thicker pial membrane-all associated with syringomyelia-will increase transpial flux and retard wave travel. It was also revealed that the propagation of a pressure wave is aided by a less-permeable pial membrane and, in contrast, by a more-permeable spinal cord. This is the first modeling of the spinal canal to include both pressure-wave propagation along the spinal axis and a pathway for fluid to enter and leave the cord, which provides an analytical foundation from which to approach the full poroelastic problem.

  15. Laser-induced pressure-wave and barocaloric effect during flash diffusivity measurements

    NASA Astrophysics Data System (ADS)

    Wang, H.; Porter, W. D.; Dinwiddie, R. B.

    2017-07-01

    We report the laser-induced pressure-wave and the barocaloric effect captured by an infrared detector during thermal diffusivity measurements. Very fast (<1 ms) and negative transients during laser flash measurements were captured using the infrared detector on thin, high thermal conductivity samples. The standard thermal diffusivity analysis only focuses on the longer time scale thermal transient measured from the back-surface due to heat conduction. Previously, these negative transients or spikes were filtered out and ignored as noise or anomaly from the instrument. This study confirmed that the initial negative signal was indeed a temperature drop induced by the laser pulse. The laser pulse induced instantaneous volume expansion and the associated cooling in the specimen can be explained by the barocaloric effect. The initial cooling (<100 μs) is also known as the thermoelastic effect in which a negative temperature change is generated when the material is elastically deformed by volume expansion. A subsequent temperature oscillation in the sample was observed and only lasted about 1 ms. The pressure-wave induced thermal signal was systematically studied and analyzed. The underlying physics of photon-mechanical-thermal energy conversions and the potential of using this signal to study barocaloric effects in solids are discussed.

  16. Acoustic pressure waves induced in human heads by RF pulses from high-field MRI scanners.

    PubMed

    Lin, James C; Wang, Zhangwei

    2010-04-01

    The current evolution toward greater image resolution from magnetic resonance image (MRI) scanners has prompted the exploration of higher strength magnetic fields and use of higher levels of radio frequencies (RFs). Auditory perception of RF pulses by humans has been reported during MRI with head coils. It has shown that the mechanism of interaction for the auditory effect is caused by an RF pulse-induced thermoelastic pressure wave inside the head. We report a computational study of the intensity and frequency of thermoelastic pressure waves generated by RF pulses in the human head inside high-field MRI and clinical scanners. The U.S. Food and Drug Administration (U.S. FDA) guides limit the local specific absorption rate (SAR) in the body-including the head-to 8 W kg(-1). We present results as functions of SAR and show that for a given SAR the peak acoustic pressures generated in the anatomic head model were essentially the same at 64, 300, and 400 MHz (1.5, 7.0, and 9.4 T). Pressures generated in the anatomic head are comparable to the threshold pressure of 20 mPa for sound perception by humans at the cochlea for 4 W kg(-1). Moreover, results indicate that the peak acoustic pressure in the brain is only 2 to 3 times the auditory threshold at the U.S. FDA guideline of 8 W kg(-1). Even at a high SAR of 20 W kg(-1), where the acoustic pressure in the brain could be more than 7 times the auditory threshold, the sound pressure levels would not be more than 17 db above threshold of perception at the cochlea.

  17. In situ measurements of impact-induced pressure waves in sandstone targets

    NASA Astrophysics Data System (ADS)

    Hoerth, Tobias; Schäfer, Frank; Nau, Siegfried; Kuder, Jürgen; Poelchau, Michael H.; Thoma, Klaus; Kenkmann, Thomas

    2014-10-01

    In the present study we introduce an innovative method for the measurement of impact-induced pressure waves within geological materials. Impact experiments on dry and water-saturated sandstone targets were conducted at a velocity of 4600 m/s using 12 mm steel projectiles to investigate amplitudes, decay behavior, and speed of the waves propagating through the target material. For this purpose a special kind of piezoresistive sensor capable of recording transient stress pulses within solid brittle materials was developed and calibrated using a Split-Hopkinson pressure bar. Experimental impact parameters (projectile size and speed) were kept constant and yielded reproducible signal curves in terms of rise time and peak amplitudes. Pressure amplitudes decreased by 3 orders of magnitude within the first 250 mm (i.e., 42 projectile radii). The attenuation for water-saturated sandstone is higher compared to dry sandstone which is attributed to dissipation effects caused by relative motion between bulk material and interstitial water. The proportion of the impact energy radiated as seismic energy (seismic efficiency) is in the order of 10-3. The present study shows the feasibility of real-time measurements of waves caused by hypervelocity impacts on geological materials. Experiments of this kind lead to a better understanding of the processes in the crater subsurface during a hypervelocity impact.

  18. Landslide stability: Role of rainfall-induced, laterally propagating, pore-pressure waves

    USGS Publications Warehouse

    Priest, G.R.; Schulz, W.H.; Ellis, W.L.; Allan, J.A.; Niem, A.R.; Niem, W.A.

    2011-01-01

    The Johnson Creek Landslide is a translational slide in seaward-dipping Miocene siltstone and sandstone (Astoria Formation) and an overlying Quaternary marine terrace deposit. The basal slide plane slopes sub-parallel to the dip of the Miocene rocks, except beneath the back-tilted toe block, where it slopes inland. Rainfall events raise pore-water pressure in the basal shear zone in the form of pulses of water pressure traveling laterally from the headwall graben down the axis of the slide at rates of 1-6 m/hr. Infiltration of meteoric water and vertical pressure transmission through the unsaturated zone has been measured at ~50 mm/hr. Infiltration and vertical pressure transmission were too slow to directly raise head at the basal shear zone prior to landslide movement. Only at the headwall graben was the saturated zone shallow enough for rainfall events to trigger lateral pulses of water pressure through the saturated zone. When pressure levels in the basal shear zone exceeded thresholds defined in this paper, the slide began slow, creeping movement as an intact block. As pressures exceeded thresholds for movement in more of the slide mass, movement accelerated, and differential displacement between internal slide blocks became more pronounced. Rainfall-induced pore-pressure waves are probably a common landslide trigger wherever effective hydraulic conductivity is high and the saturated zone is located near the surface in some part of a slide. An ancillary finding is apparently greater accuracy of grouted piezometers relative to those in sand packs for measurement of pore pressures at the installed depth.

  19. Instantaneous Sediment Bed Level Response to Wave-induced Pore-pressure Gradients on a Surfzone Sandbar

    NASA Astrophysics Data System (ADS)

    Anderson, D. L.; Cox, D. T.; Mieras, R.; Puleo, J. A.; Hsu, T. J.

    2016-12-01

    Proposed physical mechanisms contributing to onshore sediment transport over sandbar crests and subsequent sandbar migration include boundary layer streaming, Stokes drift, and pressure gradients. Both horizontal and vertical gradients may be a physical link for predicting sediment transport because they relate to the strong fluid accelerations at the bed induced by steep, near-breaking waves. To understand the fluid forcing and bed response, a barred beach was constructed in a large-scale wave flume with a fixed profile to control the global wave shoaling and breaking. A moveable sediment layer was placed on the crest of the sandbar to quantify instantaneous sediment bed levels co-located with pore pressure measurements within the upper several centimeters of the bed. A wide range of wave asymmetries were forced over the same profile in individual trials of regular waves to isolate bed response due to wave motions. The total pressure gradient vector derived within the bed exhibited temporal rotations during each wave cycle, directed predominantly upwards under the trough and then rapidly rotating onshore and downwards as the wave front passed. Sharp increases in the onshore-directed pressure gradient were correlated with rapid decreases in the bed level on the order of centimeters occurring in less than 0.5 seconds. The initiation of the bed level decrease was coincident with large onshore directed pressure gradients corresponding to non-dimensional Sleath parameter values between 0.1 and 0.2, and preceded onshore-directed sheet flow sediment transport. Downward-directed vertical pressure gradients increased rapidly during bed failure, remained downward during sheet flow, and were minimal under the wave trough. The magnitude of bed level decrease was positively correlated with the degree of wave asymmetry and exhibited additional dependency on the magnitude of bed shear stress, suggesting pressure gradients are important for initiation of transport while total

  20. Morphological characterization of cardiac induced intracranial pressure (ICP) waves in patients with overdrainage of cerebrospinal fluid and negative ICP.

    PubMed

    Eide, Per Kristian; Sroka, Marek; Wozniak, Aleksandra; Sæhle, Terje

    2012-10-01

    Symptomatic overdrainage of cerebrospinal fluid (CSF) can be seen in shunted hydrocephalus patients and in non-shunted patients with spontaneous intracranial hypotension (SIH). In these patients, intracranial pressure (ICP) monitoring often reveals negative static ICP, while it is less understood how the pulsatile ICP (cardiac induced ICP waves) is affected. This latter aspect is addressed in the present study. A set of 40 ICP recordings from paediatric and adult hydrocephalus patients were randomly selected. Each cardiac induced ICP wave was automatically identified and manually verified by the beginning and ending diastolic minimum pressures and the systolic maximum pressure. The ICP wave parameters (static pressure, amplitude, rise time, rise time coefficient, downward coefficient, wave duration, and area-under-curve) were then automatically computed. The material of 40 ICP recordings provided a total of 3,192,166 cardiac induced ICP waves (1,292,522 in paediatric patients and 1,899,644 in adult patients). No apparent changes in ICP wave parameters were seen when mean ICP became negative, except that the parameters amplitude, rise time coefficient, downward coefficient and area under curve somewhat increased when mean ICP was below -15 mmHg.

  1. Pressure field induced in the water column by acoustic-gravity waves generated from sea bottom motion

    NASA Astrophysics Data System (ADS)

    C. A. Oliveira, Tiago; Kadri, Usama

    2016-10-01

    An uplift of the ocean bottom caused by a submarine earthquake can trigger acoustic-gravity waves that travel at near the speed of sound in water and thus may act as early tsunami precursors. We study the spatiotemporal evolution of the pressure field induced by acoustic-gravity modes during submarine earthquakes, analytically. We show that these modes may all induce comparable temporal variations in pressure at different water depths in regions far from the epicenter, though the pressure field depends on the presence of a leading acoustic-gravity wave mode. Practically, this can assist in the implementation of an early tsunami detection system by identifying the pressure and frequency ranges of measurement equipment and appropriate installation locations.

  2. Pressure-induced quenching of the charge-density-wave state observed by x-ray diffraction

    SciTech Connect

    Sacchetti, A.

    2010-05-03

    We report an x-ray diffraction study on the charge-density-wave (CDW) LaTe{sub 3} and CeTe{sub 3} compounds as a function of pressure. We extract the lattice constants and the CDW modulation wave-vector, and provide direct evidence for a pressure-induced quenching of the CDW phase. We observe subtle differences between the chemical and mechanical compression of the lattice. We account for these with a scenario where the effective dimensionality in these CDW systems is dependent on the type of lattice compression and has a direct impact on the degree of Fermi surface nesting and on the strength of fluctuation effects.

  3. Time evolution of laser-ablation plumes and induced shock waves in low-pressure gas

    NASA Astrophysics Data System (ADS)

    Chiba, Rimpei; Ishikawa, Yuta; Hasegawa, Jun; Horioka, Kazuhiko

    2017-06-01

    We investigated correlations between the temporal evolutions of shock waves and plasma plumes generated by pulsed laser ablation of an aluminum target under various background gas pressures. Using a probe-beam deflection technique with a high-gain amplifier, we succeeded in detecting relatively weak shock waves in a thin gas with a pressure down to 200 Pa, which is considered to be a suitable condition for cluster formation. The behavior of the expanding plume was also observed using a high-speed framing camera and compared with that of the shock wave. The result shows that the shock front forms just ahead of the plume in the early expansion stages. The plume expansion rapidly attenuates with time and finally ceases, whereas the shock wave continues to propagate and gradually converts into a sound wave. The point-explosion blast wave model is able to estimate the transition of the temperature behind the shock front at low background pressures, giving valuable information for investigating the growth of clusters in the boundary region between the plume and background gas.

  4. Shock wave reflection induced detonation (SWRID) under high pressure and temperature condition in closed cylinder

    NASA Astrophysics Data System (ADS)

    Wang, Z.; Qi, Y.; Liu, H.; Zhang, P.; He, X.; Wang, J.

    2016-09-01

    Super-knock is one of the major obstacles for improving power density in advanced internal combustion engines (ICE). This work studied the mechanism of super-knock initiation using a rapid compression machine that simulated conditions relevant to ICEs and provided excellent optical accessibility. Based on the high-speed images and pressure traces of the stoichiometric iso-octane/oxygen/nitrogen combustion under high-temperature and high-pressure conditions, it was observed that detonation was first initiated in the near-wall region as a result of shock wave reflection. Before detonation was initiated, the speed of the combustion wave front was less than that of the Chapman-Jouguet (C-J) detonation speed (around 1840 m/s). In the immediate vicinity of the initiation, the detonation speed was much higher than that of the C-J detonation.

  5. Transdermal drug delivery with a pressure wave.

    PubMed

    Doukas, Apostolos G; Kollias, Nikiforos

    2004-03-27

    Pressure waves, which are generated by intense laser radiation, can permeabilize the stratum corneum (SC) as well as the cell membrane. These pressure waves are compression waves and thus exclude biological effects induced by cavitation. Their amplitude is in the hundreds of atmospheres (bar) while the duration is in the range of nanoseconds to a few microseconds. The pressure waves interact with cells and tissue in ways that are probably different from those of ultrasound. Furthermore, the interactions of the pressure waves with tissue are specific and depend on their characteristics, such as peak pressure, rise time and duration. A single pressure wave is sufficient to permeabilize the SC and allow the transport of macromolecules into the epidermis and dermis. In addition, drugs delivered into the epidermis can enter the vasculature and produce a systemic effect. For example, insulin delivered by pressure waves resulted in reducing the blood glucose level over many hours. The application of pressure waves does not cause any pain or discomfort and the barrier function of the SC always recovers.

  6. Effects of pressure characteristics on transfection efficiency in laser-induced stress wave-mediated gene delivery

    NASA Astrophysics Data System (ADS)

    Ando, Takahiro; Sato, Shunichi; Ashida, Hiroshi; Obara, Minoru

    2013-07-01

    Laser-induced stress waves (LISWs) generated by irradiating a light-absorbing medium with a pulsed laser can transiently increase the permeability of cell membranes for gene delivery. In this study, we investigated the effects of pressure characteristics of LISWs upon gene transfection efficiency using lasers with different pulse durations: a 6-ns pulsed Nd:YAG laser and 20-ns and 200-µs pulsed ruby lasers. LISWs were generated by irradiating a black rubber disk, on which a transparent plastic sheet was adhered for confinement of the laser-produced plasma. Rat dorsal skin was injected with plasmid DNA coding for luciferase, to which LISWs were applied. With nanosecond laser pulses, transfection efficiency increased linearly with increasing positive peak pressure in the range of 35 to 145 MPa, the corresponding impulse ranging from 10 to 40 Paṡs. With 200-µs laser pulses, on the other hand, efficient gene expression was observed by the application of LISWs even with a 10-fold-lower peak pressure (˜5 MPa), the corresponding impulse being as large as 430 Paṡs. These results indicate that even at low peak pressures, efficient transfection can be achieved by extending the pressure duration and hence by increasing the impulse of LISWs, while the averaged expression efficiencies were relatively low.

  7. Arterial pulse wave pressure transducer

    NASA Technical Reports Server (NTRS)

    Kim, C.; Gorelick, D.; Chen, W. (Inventor)

    1974-01-01

    An arterial pulse wave pressure transducer is introduced. The transducer is comprised of a fluid filled cavity having a flexible membrane disposed over the cavity and adapted to be placed on the skin over an artery. An arterial pulse wave creates pressure pulses in the fluid which are transduced, by a pressure sensitive transistor in direct contact with the fluid, into an electric signal. The electrical signal is representative of the pulse waves and can be recorded so as to monitor changes in the elasticity of the arterial walls.

  8. Pressure Waves in Medicine: From Tissue Injury to Drug Delivery

    NASA Astrophysics Data System (ADS)

    Doukas, Apostolos G.

    2004-07-01

    Pressure waves have the potential to cause injury to cells and tissue or enable novel therapeutic modalities, such as fragmentation of kidney stones and drug delivery. Research on the biological effects of pressure waves have shown that the biological response on depends the pressure-wave characteristics. One of the most prominent effects induced by pressure waves is the permeabilization of a number of barrier structures (cell plasma membrane, skin and microbial biofilms) and facilitate the delivery of macromolecules. The permeabilization of the barrier structure is transient and the barrier function recovers. Thus, pressure waves can induce delivery of molecular species that would not normally cross the barrier structure.

  9. Pressure Waves in the Heliosheath?

    NASA Astrophysics Data System (ADS)

    Richardson, John D.

    2017-09-01

    Models predict that solar transients drive pressure waves through the heliosphere. Pressure pulses are observed near solar maximum upstream of the termination shock and in the heliosphere. These pressure pulses may generate the plasma oscillations observed in the local interstellar medium. We investigate whether the observed plasma, particle, and magnetic field observations are consistent with the presence of pressure waves. The results are mixed. The plasma density, temperature, keV, and MeV particle intensities vary in phase with similar amplitude as expected for pressure waves. The galactic cosmic rays are correlated with the plasma and particles with a ∼30-day lag. However, the magnetic field and velocity show only a weak correlation with the plasma and particles.

  10. [Slow pressure waves during intracranial hypertension].

    PubMed

    Lemaire, J J

    1997-01-01

    Intracranial pressure waves include fast waves (pulse and respiration) and slow waves. Only the latter are considered here. Since the definition of three wave types in the pioneering works of Janny (1950) and Lundberg (1960), their study of frequential characteristics shows they are included in a spectrum where three contiguous frequency bands are individualised: the B wave band (BW) between 8 x 10(-3) Hz and 50 x 10(-3) Hz; the Infra B band (IB) below 8 x 10(-3) Hz; and the Ultra B band (UB) beyond 50 x 10(-3) Hz to 200 x 10(-3) Hz. The origin of these waves is vascular and some may be physiological. They are probably generated by central neuro-pacemakers and/or cyclic phenomena of cerebral autoregulation. They are linked with slow peripheral arterial pressure waves, with biological rhythms and with biomechanics and vasomotricity in the craniospinal enclosure. They are pathological for the slowest (IB), particularly if they are plateau waves, but the physiologic-pathologic boundary is not yet established for each type of slow waves. They can cause severe consequences if they result in major cerebral perfusion pressure changes, and if they induce or worsen herniations.

  11. Observations of wave-induced pore pressure gradients and bed level response on a surf zone sandbar

    NASA Astrophysics Data System (ADS)

    Anderson, Dylan; Cox, Dan; Mieras, Ryan; Puleo, Jack A.; Hsu, Tian-Jian

    2017-06-01

    Horizontal and vertical pressure gradients may be important physical mechanisms contributing to onshore sediment transport beneath steep, near-breaking waves in the surf zone. A barred beach was constructed in a large-scale laboratory wave flume with a fixed profile containing a mobile sediment layer on the crest of the sandbar. Horizontal and vertical pore pressure gradients were obtained by finite differences of measurements from an array of pressure transducers buried within the upper several centimeters of the bed. Colocated observations of erosion depth were made during asymmetric wave trials with wave heights between 0.10 and 0.98 m, consistently resulting in onshore sheet flow sediment transport. The pore pressure gradient vector within the bed exhibited temporal rotations during each wave cycle, directed predominantly upward under the trough and then rapidly rotating onshore and downward as the wavefront passed. The magnitude of the pore pressure gradient during each phase of rotation was correlated with local wave steepness and relative depth. Momentary bed failures as deep as 20 grain diameters were coincident with sharp increases in the onshore-directed pore pressure gradients, but occurred at horizontal pressure gradients less than theoretical critical values for initiation of the motion for compact beds. An expression combining the effects of both horizontal and vertical pore pressure gradients with bed shear stress and soil stability is used to determine that failure of the bed is initiated at nonnegligible values of both forces.Plain Language SummaryThe <span class="hlt">pressure</span> gradient present within the seabed beneath breaking <span class="hlt">waves</span> may be an important physical mechanism transporting sediment. A large-scale laboratory was used to replicate realistic surfzone conditions in controlled tests, allowing for horizontal and vertical <span class="hlt">pressure</span> gradient magnitudes and the resulting sediment bed response to be observed with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=492160','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=492160"><span>Raised intracranial <span class="hlt">pressure</span> and cerebral blood flow. 5. Effects of episodic intracranial <span class="hlt">pressure</span> <span class="hlt">waves</span> in primates.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Johnston, I H; Rowan, J O; Park, D M; Rennie, M J</p> <p>1975-01-01</p> <p>The effects of episodic <span class="hlt">waves</span> of intracranial <span class="hlt">pressure</span> on cerebral blood flow were studied in primates. Six <span class="hlt">pressure</span> <span class="hlt">waves</span> each of 20 minutes' duration and ranging from 50 to 100 mmHg in magnitude were <span class="hlt">induced</span> in baboons, at intervals of 30 minutes, in an attempt to simulate clinical plateau <span class="hlt">waves</span>. With <span class="hlt">pressure</span> <span class="hlt">waves</span> up to 75 mmHg, cerebral blood flow remained at control levels despite falling cerebral perfusion <span class="hlt">pressures</span>. Between the initial <span class="hlt">pressure</span> <span class="hlt">waves</span> a marked hyperaemia developed, with cerebral blood flow increasing by as much as 100%, and this appeared to be a means whereby adequate flow was maintained during <span class="hlt">pressure</span> <span class="hlt">waves</span>. Later <span class="hlt">pressure</span> <span class="hlt">waves</span>, up to 100 mmHg, eventually reduced blood flow below control levels, although moderately high flows were maintained during periods of very low perfusion <span class="hlt">pressure</span>. Brain metabolism was affected by eht episodic <span class="hlt">pressure</span> <span class="hlt">waves</span>, although no consistent change was seen. Images PMID:812960</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ZaMP...68...51R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ZaMP...68...51R"><span>"Fast" and "slow" <span class="hlt">pressure</span> <span class="hlt">waves</span> electrically <span class="hlt">induced</span> by nonlinear coupling in Biot-type porous medium saturated by a nematic liquid crystal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rosi, Giuseppe; Placidi, Luca; dell'Isola, Francesco</p> <p>2017-04-01</p> <p>In this paper, it is proposed a model for deformable porous media saturated by compressible nematic liquid crystal subjected to slowly varying electric fields. from a mechanical point of view, we assume that such a system can be described by means of a Biot-type model and that the mechanical action of the NLC on the solid matrix can be modeled by means of a suitable modification of Biot constitutive equations for pore <span class="hlt">pressure</span> only. The nonlinear nature of NLCs and the presence of bifurcations make the analysis particularly challenging. We prove that suitable electrical stimulus applied on the NLC specimen may <span class="hlt">induce</span> both type of Biot <span class="hlt">waves</span>, fast and slow, along with shear <span class="hlt">waves</span> in the porous matrix. This effect may be of use when one may wish to damp mechanically <span class="hlt">induced</span> <span class="hlt">pressure</span> <span class="hlt">waves</span> using Darcy dissipation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S33D2444M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S33D2444M"><span>Source duration of stress and water-<span class="hlt">pressure</span> <span class="hlt">induced</span> seismicity derived from experimental analysis of P <span class="hlt">wave</span> pulse width in granite</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Masuda, K.</p> <p>2013-12-01</p> <p>Pulse widths of P <span class="hlt">waves</span> in granite, measured in the laboratory, were analyzed to investigate source durations of rupture processes for water-<span class="hlt">pressure</span> <span class="hlt">induced</span> and stress-<span class="hlt">induced</span> microseismicity. Much evidence suggests that fluids in the subsurface are intimately linked to faulting processes. Studies of seismicity <span class="hlt">induced</span> by water injection are thus important for understanding the trigger mechanisms of earthquakes as well as for engineering applications such as hydraulic fracturing of rocks at depth for petroleum extraction. Determining the cause of seismic events is very important in seismology and engineering; however, water-<span class="hlt">pressure</span> <span class="hlt">induced</span> seismic events are difficult to distinguish from those <span class="hlt">induced</span> by purely tectonic stress. To investigate this problem, we analyzed the waveforms of acoustic emissions (AEs) produced in the laboratory by both water-<span class="hlt">pressure</span> <span class="hlt">induced</span> and stress-<span class="hlt">induced</span> microseismicity. We used a cylinder (50 mm in diameter and 100 mm in length) of medium-grained granite. We applied a differential stress of about 70% of fracture strength, to the rock sample under 40 MPa confining <span class="hlt">pressure</span> and held it constant throughout the experiment. When the primary creep stage and acoustic emissions (AEs) caused by the initial loading had ceased, we injected distilled water into the bottom end of the sample at a constant <span class="hlt">pressure</span> of 17 MPa until macroscopic fracture occurred. We analysed AE waveforms produced by stress-<span class="hlt">induced</span> AEs which occurred before the water-injection and by water-<span class="hlt">pressure</span> <span class="hlt">induced</span> AEs which occurred after the water-injection. Pulse widths were measured from the waveform traces plotted from the digital data. To investigate the source duration of the rupture process, we estimated the pulse width at the source and normalized by event magnitude to obtain a scaled pulse width at the source. After the effects of event size and hypocentral distance were removed from observed pulse widths, the ratio of the scaled source durations of water-<span class="hlt">pressure</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvB..92n0303L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvB..92n0303L"><span>Strong anharmonicity <span class="hlt">induces</span> quantum melting of charge density <span class="hlt">wave</span> in 2 H -NbSe2 under <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leroux, Maxime; Errea, Ion; Le Tacon, Mathieu; Souliou, Sofia-Michaela; Garbarino, Gaston; Cario, Laurent; Bosak, Alexey; Mauri, Francesco; Calandra, Matteo; Rodière, Pierre</p> <p>2015-10-01</p> <p>The <span class="hlt">pressure</span> and temperature dependence of the phonon dispersion of 2 H -NbSe2 is measured by inelastic x-ray scattering. A strong temperature dependent soft phonon mode, reminiscent of the charge density <span class="hlt">wave</span> (CDW), is found to persist up to a <span class="hlt">pressure</span> as high as 16 GPa, far above the critical <span class="hlt">pressure</span> at which the CDW disappears at 0 K. By using ab initio calculations beyond the harmonic approximation, we obtain an accurate, quantitative description of the (P ,T ) dependence of the phonon spectrum. Our results show that the rapid destruction of the CDW under <span class="hlt">pressure</span> is related to the zero mode vibrations—or quantum fluctuations—of the lattice renormalized by the anharmonic part of the lattice potential. The calculations also show that the low-energy longitudinal acoustic mode that drives the CDW transition barely contributes to superconductivity, explaining the insensitivity of the superconducting critical temperature to the CDW transition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730012553','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730012553"><span>The behavior of a compressible turbulent boundary layer in a shock-<span class="hlt">wave-induced</span> adverse <span class="hlt">pressure</span> gradient. Ph.D. Thesis - Washington Univ., Seattle, Aug. 1972</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rose, W. C.</p> <p>1973-01-01</p> <p>The results of an experimental investigation of the mean- and fluctuating-flow properties of a compressible turbulent boundary layer in a shock-<span class="hlt">wave-induced</span> adverse <span class="hlt">pressure</span> gradient are presented. The turbulent boundary layer developed on the wall of an axially symmetric nozzle and test section whose nominal free-stream Mach number and boundary-layer thickness Reynolds number were 4 and 100,000, respectively. The adverse <span class="hlt">pressure</span> gradient was <span class="hlt">induced</span> by an externally generated conical shock <span class="hlt">wave</span>. Mean and time-averaged fluctuating-flow data, including the complete experimental Reynolds stress tensor and experimental turbulent mass- and heat-transfer rates are presented for the boundary layer and external flow, upstream, within and downstream of the <span class="hlt">pressure</span> gradient. The mean-flow data include distributions of total temperature throughout the region of interest. The turbulent mixing properties of the flow were determined experimentally with a hot-wire anemometer. The calibration of the wires and the interpretation of the data are discussed. From the results of the investigation, it is concluded that the shock-<span class="hlt">wave</span> - boundary-layer interaction significantly alters the turbulent mixing characteristics of the boundary layer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoJI.200.1279M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoJI.200.1279M"><span>Fluid <span class="hlt">pressure</span> <span class="hlt">waves</span> trigger earthquakes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mulargia, Francesco; Bizzarri, Andrea</p> <p>2015-03-01</p> <p>Fluids-essentially meteoric water-are present everywhere in the Earth's crust, occasionally also with <span class="hlt">pressures</span> higher than hydrostatic due to the tectonic strain imposed on impermeable undrained layers, to the impoundment of artificial lakes or to the forced injections required by oil and gas exploration and production. Experimental evidence suggests that such fluids flow along preferred paths of high diffusivity, provided by rock joints and faults. Studying the coupled poroelastic problem, we find that such flow is ruled by a nonlinear partial differential equation amenable to a Barenblatt-type solution, implying that it takes place in form of solitary <span class="hlt">pressure</span> <span class="hlt">waves</span> propagating at a velocity which decreases with time as v ∝ t [1/(n - 1) - 1] with n ≳ 7. According to Tresca-Von Mises criterion, these <span class="hlt">waves</span> appear to play a major role in earthquake triggering, being also capable to account for aftershock delay without any further assumption. The measure of stress and fluid <span class="hlt">pressure</span> inside active faults may therefore provide direct information about fault potential instability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998JaJAP..37.6628S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998JaJAP..37.6628S"><span>The Role of Sub-Target in the Transversely Excited Atmospheric <span class="hlt">Pressure</span> CO 2 Laser-<span class="hlt">Induced</span> Shock-<span class="hlt">Wave</span> Plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Suliyanti, Maria; Hedwig, Rinda; Kurniawan, Hendrik; Kagawa, Kiichiro</p> <p>1998-12-01</p> <p>A transversely excited atmospheric <span class="hlt">pressure</span> (TEA) CO2 laser pulse (50 mJ, 100 ns) was focused on silicon grease which is painted on a copper plate as a subtarget with a power density of 6 GW/cm2 under reduced <span class="hlt">pressure</span>. The comparison of the characteristics of the <span class="hlt">induced</span> laser plasma between two cases, with subtarget and without subtarget was made. It is proved that the emission spectrum assigned to the silicon atom can be detected only for the case with the subtarget. It is also proved that in the absence of the subtarget, the gushing speed of the atom is very low, while for the case with subtarget, the gushing speed of atoms becomes very fast. It is shown that the setting of subtarget is very effective for producing laser-<span class="hlt">induced</span> shock <span class="hlt">wave</span> plasma and it is very effective for the realize quantitative analysis of a soft material.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EL....11537002M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EL....11537002M"><span>Role of anion ordering and effective <span class="hlt">pressure</span> in the field-<span class="hlt">induced</span> spin-density-<span class="hlt">wave</span> phase of (TMTSF)2X</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Minamidate, T.; Matsunaga, N.; Nomura, K.; Sasaki, T.</p> <p>2016-08-01</p> <p>Magnetoresistance and Hall resistance measurements were conducted in the field-<span class="hlt">induced</span> spin-density-<span class="hlt">wave</span> (FISDW) phase of (TMTSF)2ReO4 above 1.0 GPa, with an anion ordering specified by Q_\\text{AO}=(0, 1/2, 1/2) . The quantized Hall resistance shows the sequence N = 0, 1, 2, -2, 4, -4, -6, -8, \\cdots , with decreasing field that is successfully explained by the “extended standard model”. Consequently, we demonstrate that the difference between the chemical and hydrostatic <span class="hlt">pressures</span> is linked to the appearance of the peculiar FISDW phase of the TMTSF salts with Q_\\text{AO}=(0, 1/2, *) .</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AIPC.1434..459M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AIPC.1434..459M"><span>Onset behavior of standing <span class="hlt">wave</span> thermoacoustic <span class="hlt">pressure</span> <span class="hlt">wave</span> generator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mehta, Shreya; Desai, Keyur; Naik, Hemant Bhimbhai; Atrey, Milind</p> <p>2012-06-01</p> <p>A standing <span class="hlt">wave</span> type thermoacoustic <span class="hlt">pressure</span> <span class="hlt">wave</span> generator for 300 Hz operating frequency is designed and developed for helium as a working fluid. The device is designed as a half <span class="hlt">wave</span> length resonator. A parallel plate type SS 304 stack is designed and fabricated. An electric heater is used for heat supply to the hot end heat exchanger while a water cooled heat exchanger is used to maintain the other end of the stack near ambient temperature. An acoustic amplifier is used to amplify the <span class="hlt">pressure</span> ratio generated. Experiments are conducted to study the onset behavior of <span class="hlt">pressure</span> <span class="hlt">wave</span> generator in terms of temperature range. Observations are recorded using piezoelectric <span class="hlt">pressure</span> transducer. The results are obtained with different charging <span class="hlt">pressure</span> and heat inputs. A <span class="hlt">pressure</span> ratio of around 1.1 to 1.15 has been obtained using Nitrogen as a working fluid. The onset of thermoacoustic oscillations are studied for different filling <span class="hlt">pressure</span> and for a range of hot end temperature.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li class="active"><span>2</span></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_2 --> <div id="page_3" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="41"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6359686','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6359686"><span><span class="hlt">Pressure</span> measurements of nonplanar stress <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Carlson, G.H.; Charest, J.A.</p> <p>1981-01-01</p> <p>Measuring the <span class="hlt">pressure</span> of non-planar stress <span class="hlt">waves</span> using thin piezo-resistive gages requires correcting for <span class="hlt">induced</span> strain parallel to the sensing elements. A technique has been developed that permits such measurements, making use of a dual element gage. One element, Manganin, is sensitive to stress both parallel and perpendicular to the sensing element; the other element, Constantan, is primarily sensitive to stress parallel to the sensing element. The change in resistance in the Constantan element is thereby used to correct for the strain effect parallel to the Manganin element axis. Individual and combined Manganin and Constantan elements were subjected to controlled gas gun impact tests in the <span class="hlt">pressure</span> and strain ranges of 0 to 50 kbar and 0 to 7%, respectively. From planar <span class="hlt">wave</span> tests, the piezoresistivity of Constantan was found to be positive but negligible in comparison with Manganin. From combined stress and strain environments, the compression and tension strain factors of Constantan were found to be constant and equal to 2.06. The strain factors of Manganin were found to increase from 1.2 to 2.0 asymptotically in the range of 0 to 3% strain. It was experimentally demonstrated that, because of the closeness of their strain factors, the Manganin-Constantan dual element gage could be used in the differential recording mode to yield <span class="hlt">pressure</span> directly. In this mode the gage is a strain compensating gage. Analytical techniques have also been developed for more accurate strain compensation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040004324','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040004324"><span>Investigation of <span class="hlt">Pressurized</span> <span class="hlt">Wave</span> Bearings</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keith, Theo G., Jr.; Dimofte, Florin</p> <p>2003-01-01</p> <p>The <span class="hlt">wave</span> bearing has been pioneered and developed by Dr. Dimofte over the past several years. This bearing will be the main focus of this research. It is believed that the <span class="hlt">wave</span> bearing offers a number of advantages over the foil bearing, which is the bearing that NASA is currently pursuing for turbomachinery applications. The <span class="hlt">wave</span> bearing is basically a journal bearing whose film thickness varies around the circumference approximately sinusoidally, with usually 3 or 4 <span class="hlt">waves</span>. Being a rigid geometry bearing, it provides precise control of shaft centerlines. The <span class="hlt">wave</span> profile also provides good load capacity and makes the bearing very stable. Manufacturing techniques have been devised that should allow the production of <span class="hlt">wave</span> bearings almost as cheaply as conventional full-circular bearings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4902270','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4902270"><span>Non-β-blocking R-carvedilol enantiomer suppresses Ca2+ <span class="hlt">waves</span> and stress-<span class="hlt">induced</span> ventricular tachyarrhythmia without lowering heart rate or blood <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhang, Jingqun; Zhou, Qiang; Smith, Chris D.; Chen, Haiyan; Tan, Zhen; Chen, Biyi; Nani, Alma; Wu, Guogen; Song, Long-Sheng; Fill, Michael; Back, Thomas G.; Wayne Chen, S.R.</p> <p>2016-01-01</p> <p>Carvedilol is the current β-blocker of choice for suppressing ventricular tachyarrhythmia (VT). However, carvedilol’s benefits are dose-limited, attributable to its potent β-blocking activity that can lead to bradycardia and hypotension. The clinically used carvedilol is a racemic mixture of β-blocking S-carvedilol and non-β-blocking R-carvedilol. We recently reported that novel non-β-blocking carvedilol analogues are effective in suppressing arrhythmogenic Ca2+ <span class="hlt">waves</span> and stress-<span class="hlt">induced</span> VT without causing bradycardia. Thus, the non-β-blocking R-carvedilol enantiomer may also possess this favourable anti-arrhythmic property. To test this possibility, we synthesized R-carvedilol and assessed its effect on Ca2+ release and VT. Like racemic carvedilol, R-carvedilol directly reduces the open duration of the cardiac ryanodine receptor (RyR2), suppresses spontaneous Ca2+ oscillations in human embryonic kidney (HEK) 293 cells, Ca2+ <span class="hlt">waves</span> in cardiomyocytes in intact hearts and stress-<span class="hlt">induced</span> VT in mice harbouring a catecholaminergic polymorphic ventricular tachycardia (CPVT)-causing RyR2 mutation. Importantly, R-carvedilol did not significantly alter heart rate or blood <span class="hlt">pressure</span>. Therefore, the non-β-blocking R-carvedilol enantiomer represents a very promising prophylactic treatment for Ca2+-triggered arrhythmia without the bradycardia and hypotension often associated with racemic carvedilol. Systematic clinical assessments of R-carvedilol as a new anti-arrhythmic agent may be warranted. PMID:26348911</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26348911','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26348911"><span>Non-β-blocking R-carvedilol enantiomer suppresses Ca2+ <span class="hlt">waves</span> and stress-<span class="hlt">induced</span> ventricular tachyarrhythmia without lowering heart rate or blood <span class="hlt">pressure</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Jingqun; Zhou, Qiang; Smith, Chris D; Chen, Haiyan; Tan, Zhen; Chen, Biyi; Nani, Alma; Wu, Guogen; Song, Long-Sheng; Fill, Michael; Back, Thomas G; Chen, S R Wayne</p> <p>2015-09-01</p> <p>Carvedilol is the current β-blocker of choice for suppressing ventricular tachyarrhythmia (VT). However, carvedilol's benefits are dose-limited, attributable to its potent β-blocking activity that can lead to bradycardia and hypotension. The clinically used carvedilol is a racemic mixture of β-blocking S-carvedilol and non-β-blocking R-carvedilol. We recently reported that novel non-β-blocking carvedilol analogues are effective in suppressing arrhythmogenic Ca(2+) <span class="hlt">waves</span> and stress-<span class="hlt">induced</span> VT without causing bradycardia. Thus, the non-β-blocking R-carvedilol enantiomer may also possess this favourable anti-arrhythmic property. To test this possibility, we synthesized R-carvedilol and assessed its effect on Ca(2+) release and VT. Like racemic carvedilol, R-carvedilol directly reduces the open duration of the cardiac ryanodine receptor (RyR2), suppresses spontaneous Ca(2+) oscillations in human embryonic kidney (HEK) 293 cells, Ca(2+) <span class="hlt">waves</span> in cardiomyocytes in intact hearts and stress-<span class="hlt">induced</span> VT in mice harbouring a catecholaminergic polymorphic ventricular tachycardia (CPVT)-causing RyR2 mutation. Importantly, R-carvedilol did not significantly alter heart rate or blood <span class="hlt">pressure</span>. Therefore, the non-β-blocking R-carvedilol enantiomer represents a very promising prophylactic treatment for Ca(2+)- triggered arrhythmia without the bradycardia and hypotension often associated with racemic carvedilol. Systematic clinical assessments of R-carvedilol as a new anti-arrhythmic agent may be warranted. © 2015 Authors; published by Portland Press Limited.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PlST...18..131L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PlST...18..131L"><span>Influence of Plasma <span class="hlt">Pressure</span> Fluctuation on RF <span class="hlt">Wave</span> Propagation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Zhiwei; Bao, Weimin; Li, Xiaoping; Liu, Donglin; Zhou, Hui</p> <p>2016-02-01</p> <p><span class="hlt">Pressure</span> fluctuations in the plasma sheath from spacecraft reentry affect radio-frequency (RF) <span class="hlt">wave</span> propagation. The influence of these fluctuations on <span class="hlt">wave</span> propagation and <span class="hlt">wave</span> properties is studied using methods derived by synthesizing the compressible turbulent flow theory, plasma theory, and electromagnetic <span class="hlt">wave</span> theory. We study these influences on <span class="hlt">wave</span> propagation at GPS and Ka frequencies during typical reentry by adopting stratified modeling. We analyzed the variations in reflection and transmission properties <span class="hlt">induced</span> by <span class="hlt">pressure</span> fluctuations. Our results show that, at the GPS frequency, if the <span class="hlt">waves</span> are not totally reflected then the <span class="hlt">pressure</span> fluctuations can remarkably affect reflection, transmission, and absorption properties. In extreme situations, the fluctuations can even cause blackout. At the Ka frequency, the influences are obvious when the <span class="hlt">waves</span> are not totally transmitted. The influences are more pronounced at the GPS frequency than at the Ka frequency. This suggests that the latter can mitigate blackout by reducing both the reflection and the absorption of <span class="hlt">waves</span>, as well as the influences of plasma fluctuations on <span class="hlt">wave</span> propagation. Given that communication links with the reentry vehicles are susceptible to plasma <span class="hlt">pressure</span> fluctuations, the influences on link budgets should be taken into consideration. supported by the National Basic Research Program of China (No. 2014CB340205) and National Natural Science Foundation of China (No. 61301173)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15..270A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15..270A"><span>Extreme Vortical <span class="hlt">Waves</span> Under External <span class="hlt">Pressure</span> Action</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abrashkin, Anatoly; Soloviev, Alexander</p> <p>2013-04-01</p> <p>A vortical model for deep-water freak <span class="hlt">wave</span> formation is presented. The wind action is simulated by non-uniform <span class="hlt">pressure</span> on the free surface. The motion of the fluid is described by exact solution of 2D hydrodynamics equations for ideal inviscid fluid in Lagrange variables. Two types of flows are studied: the breather and freak <span class="hlt">wave</span> in the field of Gerstner <span class="hlt">wave</span>. Fluid particles rotate in circles of different radius and drift current is absent. The <span class="hlt">pressure</span> on free surface is non-uniform and opposite in phase with the <span class="hlt">wave</span> profile. It is examined alternating-sign and sign-constant negative distributions of the <span class="hlt">pressure</span>. Dynamics of free surface and <span class="hlt">pressure</span> for extreme <span class="hlt">waves</span> are calculated. Unlike other models the analyzed flows are vortical. The vorticity is located mostly in the neighborhood of their peaks. For enough large amplitudes it has been found the effect of the <span class="hlt">wave</span> overturn. The influence of distribution of the <span class="hlt">pressure</span> and vorticity on appearance and character of the overturn are studied. It has been found that increasing of horizontal velocity of fluid with the height causes the overturn as in the case of simple <span class="hlt">wave</span>. It is shown that the height of freak <span class="hlt">wave</span> depends on the steepness of Gerstner <span class="hlt">wave</span>. If its value is near to 1, then the height tends to 0. The freak <span class="hlt">wave</span> can not form on a steep Gerstner flow. For small steepness the ratio between the height of the peak and Gerstner <span class="hlt">wave</span> amplitude can reach 10 and even more. The <span class="hlt">wave</span> of maximal amplitude has length from the range 20-60 m.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27564297','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27564297"><span>Improvement of erectile dysfunction by the active pepide from Urechis unicinctus by high temperature/<span class="hlt">pressure</span> and ultra - <span class="hlt">wave</span> assisted lysis in Streptozotocin <span class="hlt">Induced</span> Diabetic Rats.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kim, Kang Sup; Bae, Woong Jin; Kim, Su Jin; Kang, Kyong-Hwa; Kim, Se-Kwon; Cho, Hyuk Jin; Hong, Sung-Hoo; Lee, Ji Youl; Kim, Sae Woong</p> <p>2016-01-01</p> <p>We investigate the effect of active peptide from Urechis unicinctus (UU) by high temperature/<span class="hlt">pressure</span> and ultra-<span class="hlt">wave</span> assisted lysis on erectile dysfunction in streptozotocin-<span class="hlt">induced</span> diabetic rats. Forty 12-week-old Sprague-Dawley rats were used in this study. Diabetes was <span class="hlt">induced</span> by a one-time intraperitoneal injection of streptozotocin (50mg/kg). One week later, the diabetic rats were randomly divided into four groups: normal control, untreated diabetes control, and groups treated with 100 or 500mg/kg/d UU peptide. Rats were fed with UU peptide by intragastric administration for 8 weeks. After 8 weeks, penile hemodynamic function was evaluated in all groups by measuring the intracavernosal <span class="hlt">pressure</span> after electrostimulating the cavernous nerve. Nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) activities were measured and endothelial nitric oxide synthase (eNOS) and neuronal NOS (nNOS) protein expression. was determined by Western blot. Maximum intracavernosal <span class="hlt">pressure</span> in diabetic control rats decreased significantly compared to normal control rats, and was increased significantly compared to untreated diabetic rats after UU peptide supplementation. Treatment with the higher dose of UU peptide significantly increased the NO and cGMP levels compared with the diabetic control group. Decreased activity and expression eNOS and nNOS were found in the diabetic rats compared with the normal control group. Decreased eNOS and nNOS in diabetic rats were improved by UU peptide administration. Active peptide from UU ameliorates erectile function in a streptozotocin <span class="hlt">induced</span> diabetic rat model of erectile dysfunction. Copyright© by the International Brazilian Journal of Urology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5006782','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5006782"><span>Improvement of erectile dysfunction by the active pepide from Urechis unicinctus by high temperature/<span class="hlt">pressure</span> and ultra - <span class="hlt">wave</span> assisted lysis in Streptozotocin <span class="hlt">Induced</span> Diabetic Rats</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kim, Kang Sup; Bae, Woong Jin; Kim, Su Jin; Kang, Kyong-Hwa; Kim, Se-Kwon; Cho, Hyuk Jin; Hong, Sung-Hoo; Lee, Ji Youl; Kim, Sae Woong</p> <p>2016-01-01</p> <p>ABSTRACT Introduction: We investigate the effect of active peptide from Urechis unicinctus (UU) by high temperature/<span class="hlt">pressure</span> and ultra-<span class="hlt">wave</span> assisted lysis on erectile dysfunction in streptozotocin-<span class="hlt">induced</span> diabetic rats. Materials and Methods: Forty 12-week-old Sprague-Dawley rats were used in this study. Diabetes was <span class="hlt">induced</span> by a one-time intraperitoneal injection of streptozotocin (50mg/kg). One week later, the diabetic rats were randomly divided into four groups: normal control, untreated diabetes control, and groups treated with 100 or 500mg/kg/d UU peptide. Rats were fed with UU peptide by intragastric administration for 8 weeks. After 8 weeks, penile hemodynamic function was evaluated in all groups by measuring the intracavernosal <span class="hlt">pressure</span> after electrostimulating the cavernous nerve. Nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) activities were measured and endothelial nitric oxide synthase (eNOS) and neuronal NOS (nNOS) protein expression was determined by Western blot. Results: Maximum intracavernosal <span class="hlt">pressure</span> in diabetic control rats decreased significantly compared to normal control rats, and was increased significantly compared to untreated diabetic rats after UU peptide supplementation. Treatment with the higher dose of UU peptide significantly increased the NO and cGMP levels compared with the diabetic control group. Decreased activity and expression eNOS and nNOS were found in the diabetic rats compared with the normal control group. Decreased eNOS and nNOS in diabetic rats were improved by UU peptide administration. Conclusions: Active peptide from UU ameliorates erectile function in a streptozotocin <span class="hlt">induced</span> diabetic rat model of erectile dysfunction. PMID:27564297</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70034415','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70034415"><span><span class="hlt">Pressure</span> <span class="hlt">waves</span> in a supersaturated bubbly magma</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Kurzon, I.; Lyakhovsky, V.; Navon, O.; Chouet, B.</p> <p>2011-01-01</p> <p>We study the interaction of acoustic <span class="hlt">pressure</span> <span class="hlt">waves</span> with an expanding bubbly magma. The expansion of magma is the result of bubble growth during or following magma decompression and leads to two competing processes that affect <span class="hlt">pressure</span> <span class="hlt">waves</span>. On the one hand, growth in vesicularity leads to increased damping and decreased <span class="hlt">wave</span> amplitudes, and on the other hand, a decrease in the effective bulk modulus of the bubbly mixture reduces <span class="hlt">wave</span> velocity, which in turn, reduces damping and may lead to <span class="hlt">wave</span> amplification. The additional acoustic energy originates from the chemical energy released during bubble growth. We examine this phenomenon analytically to identify conditions under which amplification of <span class="hlt">pressure</span> <span class="hlt">waves</span> is possible. These conditions are further examined numerically to shed light on the frequency and phase dependencies in relation to the interaction of <span class="hlt">waves</span> and growing bubbles. Amplification is possible at low frequencies and when the growth rate of bubbles reaches an optimum value for which the <span class="hlt">wave</span> velocity decreases sufficiently to overcome the increased damping of the vesicular material. We examine two amplification phase-dependent effects: (1) a tensile-phase effect in which the inserted <span class="hlt">wave</span> adds to the process of bubble growth, utilizing the energy associated with the gas overpressure in the bubble and therefore converting a large proportion of this energy into additional acoustic energy, and (2) a compressive-phase effect in which the <span class="hlt">pressure</span> <span class="hlt">wave</span> works against the growing bubbles and a large amount of its acoustic energy is dissipated during the first cycle, but later enough energy is gained to amplify the second cycle. These two effects provide additional new possible mechanisms for the amplification phase seen in Long-Period (LP) and Very-Long-Period (VLP) seismic signals originating in magma-filled cracks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013Chaos..23c3128M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013Chaos..23c3128M"><span>Modulated <span class="hlt">pressure</span> <span class="hlt">waves</span> in large elastic tubes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mefire Yone, G. R.; Tabi, C. B.; Mohamadou, A.; Ekobena Fouda, H. P.; Kofané, T. C.</p> <p>2013-09-01</p> <p>Modulational instability is the direct way for the emergence of <span class="hlt">wave</span> patterns and localized structures in nonlinear systems. We show in this work that it can be explored in the framework of blood flow models. The whole modified Navier-Stokes equations are reduced to a difference-differential amplitude equation. The modulational instability criterion is therefore derived from the latter, and unstable patterns occurrence is discussed on the basis of the nonlinear parameter model of the vessel. It is found that the critical amplitude is an increasing function of α, whereas the region of instability expands. The subsequent modulated <span class="hlt">pressure</span> <span class="hlt">waves</span> are obtained through numerical simulations, in agreement with our analytical expectations. Different classes of modulated <span class="hlt">pressure</span> <span class="hlt">waves</span> are obtained, and their close relationship with Mayer <span class="hlt">waves</span> is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/864416','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/864416"><span><span class="hlt">Pressure</span> <span class="hlt">wave</span> charged repetitively pulsed gas laser</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Kulkarny, Vijay A.</p> <p>1982-01-01</p> <p>A repetitively pulsed gas laser in which a system of mechanical shutters bracketing the laser cavity manipulate <span class="hlt">pressure</span> <span class="hlt">waves</span> resulting from residual energy in the cavity gas following a lasing event so as to draw fresh gas into the cavity and effectively pump spent gas in a dynamic closed loop.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950007424','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950007424"><span>Surface acoustic <span class="hlt">wave</span> oxygen <span class="hlt">pressure</span> sensor</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Oglesby, Donald M. (Inventor); Upchurch, Billy T. (Inventor); Leighty, Bradley D. (Inventor)</p> <p>1994-01-01</p> <p>A transducer for the measurement of absolute gas-state oxygen <span class="hlt">pressure</span> from <span class="hlt">pressures</span> of less than 100 Pa to atmospheric <span class="hlt">pressure</span> (1.01 x 10(exp 5) Pa) is based on a standard surface acoustic <span class="hlt">wave</span> (SAW) device. The piezoelectric material of the SAW device is coated with a compound which will selectively and reversibly bind oxygen. When oxygen is bound by the coating, the mass of the coating increases by an amount equal to the mass of the bound oxygen. Such an increase in the mass of the coating causes a corresponding decrease in the resonant frequency of the SAW device.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvS..19i3501D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvS..19i3501D"><span>Propagation of elastic <span class="hlt">pressure</span> <span class="hlt">waves</span> in a beam window</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Davenne, T. R.; Loveridge, P.</p> <p>2016-09-01</p> <p>As particle accelerator beam power increases, stress on beam windows and targets increases. Many simulations are carried out to model the dynamic stresses that are <span class="hlt">induced</span> in these critical components by near instantaneous beam heating. However while it is often easy to obtain simulation results there are few analytical solutions available to check the accuracy of simulation techniques. We follow the strand of several authors over the years who have offered analytical solutions to the classic problem of radial stress <span class="hlt">waves</span> in a beam window. Many of these significant contributions have still had niggling issues with regard to resolving peak stress and limitations on the applied initial heating condition. We formulate an analytical expression for the radial <span class="hlt">pressure</span> <span class="hlt">waves</span> based on a Green's function solution of Feynman's <span class="hlt">wave</span> equation. A complete analysis of the problem demonstrates that a hypothesis that beam <span class="hlt">induced</span> <span class="hlt">pressure</span> <span class="hlt">waves</span> are composed of a static and transient component is indeed correct. The analytical expression is shown to give stable bounded solutions with easily determined peak stress levels. Finally a comparison between analytical expression and finite element analysis of the problem yields some general guidelines that should be adhered to for achieving accurate stress <span class="hlt">wave</span> simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730058006&hterms=flame+treatment&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dflame%2Btreatment','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730058006&hterms=flame+treatment&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dflame%2Btreatment"><span><span class="hlt">Pressure</span> <span class="hlt">waves</span> generated by steady flames.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kuhl, A. L.; Kamel, M. M.; Oppenheim, A. K.</p> <p>1973-01-01</p> <p>Analysis of <span class="hlt">pressure</span> <span class="hlt">waves</span> that can be generated by clouds of explosive gas mixtures in a free atmosphere which is initially at a uniform state. The treatment is restricted only to the final stage of constant flame velocity when the flowfield is self-similar. By the introduction of reduced blast-<span class="hlt">wave</span> parameters as phase-plane coordinates, the problem is resolved into the determination of the appropriate integral curves on this plane. Results, including space profiles of gasdynamic parameters, have been computed for a specific case of a hydrocarbon-air mixture characterized by a specific heat ratio of 1.3, sound speed at NTP of 345 m/sec, and volumetric expansion ratio corresponding to constant <span class="hlt">pressure</span> deflagration of 7. Maximum overpressure ratios that can be generated by such flames in point-and line-symmetrical <span class="hlt">waves</span> range from .00053, for the lower bound in the burning speed, up to 6 for the deflagration, while, for the average speeds of 5 to 10 m/sec, they are at a level of 0.05 to 0.10.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730058006&hterms=deflagration&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Ddeflagration','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730058006&hterms=deflagration&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Ddeflagration"><span><span class="hlt">Pressure</span> <span class="hlt">waves</span> generated by steady flames.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kuhl, A. L.; Kamel, M. M.; Oppenheim, A. K.</p> <p>1973-01-01</p> <p>Analysis of <span class="hlt">pressure</span> <span class="hlt">waves</span> that can be generated by clouds of explosive gas mixtures in a free atmosphere which is initially at a uniform state. The treatment is restricted only to the final stage of constant flame velocity when the flowfield is self-similar. By the introduction of reduced blast-<span class="hlt">wave</span> parameters as phase-plane coordinates, the problem is resolved into the determination of the appropriate integral curves on this plane. Results, including space profiles of gasdynamic parameters, have been computed for a specific case of a hydrocarbon-air mixture characterized by a specific heat ratio of 1.3, sound speed at NTP of 345 m/sec, and volumetric expansion ratio corresponding to constant <span class="hlt">pressure</span> deflagration of 7. Maximum overpressure ratios that can be generated by such flames in point-and line-symmetrical <span class="hlt">waves</span> range from .00053, for the lower bound in the burning speed, up to 6 for the deflagration, while, for the average speeds of 5 to 10 m/sec, they are at a level of 0.05 to 0.10.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15742722','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15742722"><span>Hydrocephalus shunts and <span class="hlt">waves</span> of intracranial <span class="hlt">pressure</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Czosnyka, Z H; Cieslicki, K; Czosnyka, M; Pickard, J D</p> <p>2005-01-01</p> <p>The majority of contemporary hydrocephalus valves are designed to introduce a low resistance to flow into the cerebrospinal fluid (CSF) drainage pathway, and an therefore intended to stabilise intracranial <span class="hlt">pressure</span> (ICP) at a level close to the shunt's operating <span class="hlt">pressure</span>. However, this goal cannot always be attained. Accelerated CSF drainage with vertical body posture in ventriculo-peritoneal shunts is one reason for the ICP decreasing below the shunt's operating <span class="hlt">pressure</span>. Another possible factor has been studied: the impact of the pulsating pattern in the ICP on the operating <span class="hlt">pressure</span>. Six popular constructions of medium-<span class="hlt">pressure</span> valves were studied (Radionics Low-profile, Delta, Hakim Precision, Holter, Integra In-line and Hakim NMT). Valves were mounted in the testing rig in the UK. Shunt Evaluation Laboratory and perfused with de-ionised water at a rate of 0.3 ml min(-1), and proximal pulsating <span class="hlt">pressures</span> of different amplitudes (from 2 to 30mmHg peak-to-peak) and frequencies (70-10 cycles min(-1)) were superimposed. Laboratory findings were compared with clinical material containing recordings of ICP made in patients to diagnose reasons for ventriculomegaly. The mean operating <span class="hlt">pressure</span> decreased in all valves when the simulated amplitude of heart pulsations increased. The rate of this decrease was dependent on the type of valve (variable from 2.5 to 5 mm Hg per increase in peak-to-peak amplitude by 10 mm Hg). The decrease was not related to the frequency of the <span class="hlt">wave</span>. The relationship between pulse amplitude and ICP in 35 patients with blocked shunts was strong (R = 0.48; p < 0.03; slope 0.14) and in 25 patients with properly functioning shunts was non-significant (R = 0.057; p = 0.765). Two examples of decrease in mean ICP in the presence of increased vasogenic ICP <span class="hlt">waves</span> in shunted patients are presented. The shunt operating <span class="hlt">pressure</span>, which 'sets' the ICP in shunted patients may be influenced by the dynamics of a patient's ICP waveform.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ArRMA.218.1131W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ArRMA.218.1131W"><span>Solitary Water <span class="hlt">Waves</span> of Large Amplitude Generated by Surface <span class="hlt">Pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wheeler, Miles H.</p> <p>2015-11-01</p> <p>We consider exact nonlinear solitary water <span class="hlt">waves</span> on a shear flow with an arbitrary distribution of vorticity. Ignoring surface tension, we impose a non-constant <span class="hlt">pressure</span> on the free surface. Starting from a uniform shear flow with a flat free surface and a supercritical <span class="hlt">wave</span> speed, we vary the surface <span class="hlt">pressure</span> and use a continuation argument to construct a global connected set of symmetric solitary <span class="hlt">waves</span>. This set includes <span class="hlt">waves</span> of depression whose profiles increase monotonically from a central trough where the surface <span class="hlt">pressure</span> is at its lowest, as well as <span class="hlt">waves</span> of elevation whose profiles decrease monotonically from a central crest where the surface <span class="hlt">pressure</span> is at its highest. There may also be two <span class="hlt">waves</span> in this connected set with identical surface <span class="hlt">pressure</span>, only one of which is a <span class="hlt">wave</span> of depression.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920043058&hterms=cfl&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dcfl','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920043058&hterms=cfl&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dcfl"><span><span class="hlt">Pressure</span> <span class="hlt">wave</span> propagation studies for oscillating cascades</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Huff, Dennis L.</p> <p>1992-01-01</p> <p>The unsteady flowfield around an oscillating cascade of flat plates is studied using a time marching Euler code. Exact solutions based on linear theory serve as model problems to study <span class="hlt">pressure</span> <span class="hlt">wave</span> propagation in the numerical solution. The importance of using proper unsteady boundary conditions, grid resolution, and time step is demonstrated. Results show that an approximate non-reflecting boundary condition based on linear theory does a good job of minimizing reflections from the inflow and outflow boundaries and allows the placement of the boundaries to be closer than cases using reflective boundary conditions. Stretching the boundary to dampen the unsteady <span class="hlt">waves</span> is another way to minimize reflections. Grid clustering near the plates does a better job of capturing the unsteady flowfield than cases using uniform grids as long as the CFL number is less than one for a sufficient portion of the grid. Results for various stagger angles and oscillation frequencies show good agreement with linear theory as long as the grid is properly resolved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19920006759','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19920006759"><span><span class="hlt">Pressure</span> <span class="hlt">wave</span> propagation studies for oscillating cascades</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Huff, Dennis L.</p> <p>1992-01-01</p> <p>The unsteady flow field around an oscillating cascade of flat plates is studied using a time marching Euler code. Exact solutions based on linear theory serve as model problems to study <span class="hlt">pressure</span> <span class="hlt">wave</span> propagation in the numerical solution. The importance of using proper unsteady boundary conditions, grid resolution, and time step is demonstrated. Results show that an approximate non-reflecting boundary condition based on linear theory does a good job of minimizing reflections from the inflow and outflow boundaries and allows the placement of the boundaries to be closer than cases using reflective boundary conditions. Stretching the boundary to dampen the unsteady <span class="hlt">waves</span> is another way to minimize reflections. Grid clustering near the plates does a better job of capturing the unsteady flow field than cases using uniform grids as long as the CFL number is less than one for a sufficient portion of the grid. Results for various stagger angles and oscillation frequencies show good agreement with linear theory as long as the grid is properly resolved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920043058&hterms=wave+flat&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dwave%2Bflat','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920043058&hterms=wave+flat&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dwave%2Bflat"><span><span class="hlt">Pressure</span> <span class="hlt">wave</span> propagation studies for oscillating cascades</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Huff, Dennis L.</p> <p>1992-01-01</p> <p>The unsteady flowfield around an oscillating cascade of flat plates is studied using a time marching Euler code. Exact solutions based on linear theory serve as model problems to study <span class="hlt">pressure</span> <span class="hlt">wave</span> propagation in the numerical solution. The importance of using proper unsteady boundary conditions, grid resolution, and time step is demonstrated. Results show that an approximate non-reflecting boundary condition based on linear theory does a good job of minimizing reflections from the inflow and outflow boundaries and allows the placement of the boundaries to be closer than cases using reflective boundary conditions. Stretching the boundary to dampen the unsteady <span class="hlt">waves</span> is another way to minimize reflections. Grid clustering near the plates does a better job of capturing the unsteady flowfield than cases using uniform grids as long as the CFL number is less than one for a sufficient portion of the grid. Results for various stagger angles and oscillation frequencies show good agreement with linear theory as long as the grid is properly resolved.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_3 --> <div id="page_4" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="61"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004APS..MARD28009T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004APS..MARD28009T"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> polymerization of Formates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tschauner, Oliver</p> <p>2004-03-01</p> <p>The discovery of <span class="hlt">pressure</span> <span class="hlt">induced</span> polymerization of CO2 inspired us to search for C-O based chain structures forming at high <span class="hlt">pressure</span>. We used salts of carboxylic acids as starting materials and exposed them to <span class="hlt">pressures</span> between 10 and 30 GPa. Upon heating to temperatures above 1800 K we observed deprotonation and significant changes in the Raman shifts of C-O streching modes. Structure analysis based on powder diffraction patterns collected at sector 16 of the APS showed formation of extended C-O chain structures with the cations of the salts residing in the interchain spaces. These new high <span class="hlt">pressure</span> polymers are interesting by their mechanical strength and provide basic molecular patterns of organic metallic conductors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006JPCS...67.2095M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006JPCS...67.2095M"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> metallization of Germane</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martinez-Canales, M.; Bergara, A.; Feng, J.; Grochala, W.</p> <p>2006-09-01</p> <p>Recently reported superconductivity in lithium under <span class="hlt">pressure</span> has renewed the interest on hydrogen and hydrogen-rich systems in the long standing quest for room temperature superconductivity. Although the required metallization of pure hydrogen cannot be achieved within correct experimental capabilities, chemical precompression exerted by heavier atoms in compounds with a large hydrogen content is expected to imply that lower <span class="hlt">pressures</span> might be required to attain the metallic transition in these alloys. In this article, we present an ab initio analysis of <span class="hlt">pressure</span> <span class="hlt">induced</span> metallization of germane, as a particular case between group IVa hydrides. According to our calculations, metallization of germane is predicted to occur at an experimentally accessible <span class="hlt">pressure</span> of around 70 GPa, which corresponds to a compression factor of 3.4.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24237537','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24237537"><span>Measurement of elastic <span class="hlt">waves</span> <span class="hlt">induced</span> by the reflection of light.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Požar, Tomaž; Možina, Janez</p> <p>2013-11-01</p> <p>The reflection of light from the surface of an elastic solid gives rise to various types of elastic <span class="hlt">waves</span> that propagate inside the solid. The weakest <span class="hlt">waves</span> are generally those that are generated by the radiation <span class="hlt">pressure</span> acting during the reflection of the light. Here, we present the first quantitative measurement of such light-<span class="hlt">pressure-induced</span> elastic <span class="hlt">waves</span> inside an ultrahigh-reflectivity mirror. Amplitudes of a few picometers were observed at the rear side of the mirror with a displacement-measuring conical piezoelectric sensor when laser pulses with a fluence of 1 J/cm(2) were reflected from the front side of the mirror.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005ASAJ..118..178M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005ASAJ..118..178M"><span>A suppressor to prevent direct <span class="hlt">wave-induced</span> cavitation in shock <span class="hlt">wave</span> therapy devices</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Matula, Thomas J.; Hilmo, Paul R.; Bailey, Michael R.</p> <p>2005-07-01</p> <p>Cavitation plays a varied but important role in lithotripsy. Cavitation facilitates stone comminution, but can also form an acoustic barrier that may shield stones from subsequent shock <span class="hlt">waves</span>. In addition, cavitation damages tissue. Spark-gap lithotripters generate cavitation with both a direct and a focused <span class="hlt">wave</span>. The direct <span class="hlt">wave</span> propagates as a spherically diverging <span class="hlt">wave</span>, arriving at the focus ahead of the focused shock <span class="hlt">wave</span>. It can be modeled with the same waveform (but lower amplitude) as the focused <span class="hlt">wave</span>. We show with both simulations and experiments that bubbles are forced to grow in response to the direct <span class="hlt">wave</span>, and that these bubbles can still be large when the focused shock <span class="hlt">wave</span> arrives. A baffle or ``suppressor'' that blocks the propagation of the direct <span class="hlt">wave</span> is shown to significantly reduce the direct <span class="hlt">wave</span> <span class="hlt">pressure</span> amplitude, as well as direct <span class="hlt">wave-induced</span> bubble growth. These results are applicable to spark-gap lithotripters and extracorporeal shock <span class="hlt">wave</span> therapy devices, where cavitation from the direct <span class="hlt">wave</span> may interfere with treatment. A simple direct-<span class="hlt">wave</span> suppressor might therefore be used to improve the therapeutic efficacy of these devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810012780','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810012780"><span>On the <span class="hlt">pressure</span> field of nonlinear standing water <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schwartz, L. W.</p> <p>1980-01-01</p> <p>The <span class="hlt">pressure</span> field produced by two dimensional nonlinear time and space periodic standing <span class="hlt">waves</span> was calculated as a series expansion in the <span class="hlt">wave</span> height. The high order series was summed by the use of Pade approximants. Calculations included the <span class="hlt">pressure</span> variation at great depth, which was considered to be a likely cause of microseismic activity, and the <span class="hlt">pressure</span> distribution on a vertical barrier or breakwater.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApPhL.109w2407D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApPhL.109w2407D"><span>Reconfigurable heat-<span class="hlt">induced</span> spin <span class="hlt">wave</span> lenses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dzyapko, O.; Borisenko, I. V.; Demidov, V. E.; Pernice, W.; Demokritov, S. O.</p> <p>2016-12-01</p> <p>We study the control and manipulation of propagating spin <span class="hlt">waves</span> in yttrium iron garnet films using a local laser-<span class="hlt">induced</span> heating. We show that, due to the refraction of spin <span class="hlt">waves</span> in the thermal gradients, the heated region acts as a defocusing lens for Damon-Eshbach spin <span class="hlt">waves</span> and as a focusing lens for backward volume <span class="hlt">waves</span> enabling collimation of spin-<span class="hlt">wave</span> beams in the latter case. In addition to the focusing/defocusing functionality, the local heating allows one to manipulate the propagation direction of the spin-<span class="hlt">wave</span> beams and to efficiently suppress their diffraction spreading by utilizing caustic effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.H24D..06M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.H24D..06M"><span><span class="hlt">Wave-Induced</span> Groundwater Flows in a Freshwater Beach Aquifer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Malott, S. S.; Robinson, C. E.; O'Carroll, D. M.</p> <p>2014-12-01</p> <p><span class="hlt">Wave-induced</span> recirculation across the sediment-water interface can impact the transport of pollutants through a beach aquifer and their ultimate flux into coastal waters. The fate of nutrients (e.g. from septic and agricultural sources) and fecal indicator bacteria (e.g. E. coil) near the sediment-water interface are of particular concern as these pollutants often lead to degradation of recreational water quality and nearshore ecosystems. This paper presents detailed field measurements of groundwater flows in a freshwater beach aquifer on Lake Huron over periods of intensified <span class="hlt">wave</span> conditions. Quantifying <span class="hlt">wave</span>-driven processes in a freshwater beach aquifer enables <span class="hlt">wave</span> effects to be studied in isolation from density and tidal effects that complicate groundwater flows in marine beaches. Water exchange across the sediment-water interface and groundwater flow patterns were measured using groundwater wells, arrays of vertically nested <span class="hlt">pressure</span> transducers and manometers. Results show that <span class="hlt">wave</span> action <span class="hlt">induces</span> rapid infiltration/exfiltration across the sediment-water interface and a larger recirculation cell through the beach aquifer. Field data is used to validate a numerical groundwater model of <span class="hlt">wave-induced</span> groundwater flows. While prior studies have simulated the effects of <span class="hlt">waves</span> on beach groundwater flows, this study is the first attempt to validate these sophisticated modeling approaches. Finally, field data illustrating the impact of <span class="hlt">wave-induced</span> groundwater flows on nutrient and bacteria fate and transport in beach aquifers will also be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27165895','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27165895"><span>Plateau <span class="hlt">Waves</span> of Intracranial <span class="hlt">Pressure</span> and Multimodal Brain Monitoring.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dias, Celeste; Maia, Isabel; Cerejo, Antonio; Smielewski, Peter; Paiva, José-Artur; Czosnyka, Marek</p> <p>2016-01-01</p> <p>The aim of this study was to describe multimodal brain monitoring characteristics during plateau <span class="hlt">waves</span> of intracranial <span class="hlt">pressure</span> (ICP) in patients with head injury, using ICM+ software for continuous recording. Plateau <span class="hlt">waves</span> consist of an abrupt elevation of ICP above 40 mmHg for 5-20 min. This is a prospective observational study of patients with head injury who were admitted to a neurocritical care unit and who developed plateau <span class="hlt">waves</span>. We analyzed 59 plateau <span class="hlt">waves</span> that occurred in 8 of 18 patients (44 %). At the top of plateau <span class="hlt">waves</span> arterial blood <span class="hlt">pressure</span> remained almost constant, but cerebral perfusion <span class="hlt">pressure</span>, cerebral blood flow, brain tissue oxygenation, and cerebral oximetry decreased. After plateau <span class="hlt">waves</span>, patients with a previously better autoregulation status developed hyperemia, demonstrated by an increase in cerebral blood flow and brain oxygenation. <span class="hlt">Pressure</span> and oxygen cerebrovascular reactivity indexes (<span class="hlt">pressure</span> reactivity index and ORxshort) increased significantly during the plateau <span class="hlt">wave</span> as a sign of disruption of autoregulation. Bedside multimodal brain monitoring is important to characterize increases in ICP and give differential diagnoses of plateau <span class="hlt">waves</span>, as management of this phenomenon differs from that of regular ICP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/3590361','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/3590361"><span>Biological effects of shock <span class="hlt">waves</span>: lung hemorrhage by shock <span class="hlt">waves</span> in dogs--<span class="hlt">pressure</span> dependence.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Delius, M; Enders, G; Heine, G; Stark, J; Remberger, K; Brendel, W</p> <p>1987-02-01</p> <p>The most serious side effect observed during the destruction of gallstones by shock <span class="hlt">waves</span> in dogs was lung bleeding. To determine the conditions leading to lung damage, <span class="hlt">pressure</span> probes were implanted into dogs between the lung and the diaphragm. The distance between the lung and the focal point of the <span class="hlt">pressure</span> field was determined at which 1000 shock <span class="hlt">waves</span> caused no more lung hemorrhage. On the long axis it is greater than 15 cm and perpendicular to the long axis it is 4 cm. Shock <span class="hlt">wave</span> <span class="hlt">pressures</span> over 2 MPa could be administered safely, whereas a <span class="hlt">pressure</span> of 10 MPa caused bleedings in beagles, but probably not in boxers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.5778G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.5778G"><span>Lower-tropospheric <span class="hlt">waves</span> and <span class="hlt">wave-induced</span> turbulence zones: Insights from T-REX</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grubisic, V.; Xiao, M.; Haimov, S.; French, J.; Oolman, L.</p> <p>2009-04-01</p> <p>During the Terrain-<span class="hlt">induced</span> Rotor Experiment (T-REX) in March/April 2006 highly turbulent flows in the lee of the Sierra Nevada were probed by the University of Wyoming King Air (UWKA) aircraft. In situ thermodynamic and kinematic data was obtained by UWKA on rotor and <span class="hlt">wave</span> structures over Owens Valley in a number of research missions under strong lee-<span class="hlt">wave</span> conditions. In situ measurements by the UWKA have been used to examine strongly turbulent flow regions documented by the UWKA and their relationship to the flow structures over Owens Valley. <span class="hlt">Wave-induced</span> <span class="hlt">pressure</span> perturbations determined from the aircraft measurements are compared with the surface <span class="hlt">pressure</span> perturbations derived from the network of surface <span class="hlt">pressure</span> sensors in Owens Valley in order to detect <span class="hlt">wave-induced</span> boundary-layer separation. Sufficiently strong signal returns from the Wyoming Cloud Radar (WCR) were granted by the presence of ice particles within different types of clouds associated with the <span class="hlt">wave</span>/rotor system, including mountain cap clouds over the Sierra crest, "spill over" clouds over the eastern Sierra slopes and in a few events rotor clouds over Owens Valley. The results of the dual-Doppler analyses for the rotor clouds reveal the presence of fine-scale structures within the roll clouds in the upper part of the rotor circulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830011423','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830011423"><span>Corotating <span class="hlt">pressure</span> <span class="hlt">waves</span> without streams in the solar wind</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burlaga, L. F.</p> <p>1983-01-01</p> <p>Voyager 1 and 2 magnetic field and plasma data are presented which demonstrate the existence of large scale, corotating, non-linear <span class="hlt">pressure</span> <span class="hlt">waves</span> between 2 AU and 4 AU that are not accompanied by fast streams. The <span class="hlt">pressure</span> <span class="hlt">waves</span> are presumed to be generated by corotating streams near the Sun. For two of the three <span class="hlt">pressure</span> <span class="hlt">waves</span> that are discussed, the absence of a stream is probably a real, physical effect, viz., a consequence of deceleration of the stream by the associated compression <span class="hlt">wave</span>. For the third <span class="hlt">pressure</span> <span class="hlt">wave</span>, the apparent absence of a stream may be a geometrical effect; it is likely that the stream was at latitudes just above those of the spacecraft, while the associated shocks and compression <span class="hlt">wave</span> extended over a broader range of latitudes so that they could be observed by the spacecraft. It is suggested that the development of large-scale non-linear <span class="hlt">pressure</span> <span class="hlt">waves</span> at the expense of the kinetic energy of streams produces a qualitative change in the solar wind in the outer heliosphere. Within a few AU the quasi-stationary solar wind structure is determined by corotating streams whose structure is determined by the boundary conditions near the Sun.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26873972','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26873972"><span>Novel <span class="hlt">wave</span> power analysis linking <span class="hlt">pressure</span>-flow <span class="hlt">waves</span>, <span class="hlt">wave</span> potential, and the forward and backward components of hydraulic power.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mynard, Jonathan P; Smolich, Joseph J</p> <p>2016-04-15</p> <p><span class="hlt">Wave</span> intensity analysis provides detailed insights into factors influencing hemodynamics. However, <span class="hlt">wave</span> intensity is not a conserved quantity, so it is sensitive to diameter variations and is not distributed among branches of a junction. Moreover, the fundamental relation between <span class="hlt">waves</span> and hydraulic power is unclear. We, therefore, propose an alternative to <span class="hlt">wave</span> intensity called "<span class="hlt">wave</span> power," calculated via incremental changes in <span class="hlt">pressure</span> and flow (dPdQ) and a novel time-domain separation of hydraulic <span class="hlt">pressure</span> power and kinetic power into forward and backward <span class="hlt">wave</span>-related components (ΠP±and ΠQ±). <span class="hlt">Wave</span> power has several useful properties:1) it is obtained directly from flow measurements, without requiring further calculation of velocity;2) it is a quasi-conserved quantity that may be used to study the relative distribution of <span class="hlt">waves</span> at junctions; and3) it has the units of power (Watts). We also uncover a simple relationship between <span class="hlt">wave</span> power and changes in ΠP±and show that <span class="hlt">wave</span> reflection reduces transmitted power. Absolute values of ΠP±represent <span class="hlt">wave</span> potential, a recently introduced concept that unifies steady and pulsatile aspects of hemodynamics. We show that <span class="hlt">wave</span> potential represents the hydraulic energy potential stored in a compliant <span class="hlt">pressurized</span> vessel, with spatial gradients producing <span class="hlt">waves</span> that transfer this energy. These techniques and principles are verified numerically and also experimentally with <span class="hlt">pressure</span>/flow measurements in all branches of a central bifurcation in sheep, under a wide range of hemodynamic conditions. The proposed "<span class="hlt">wave</span> power analysis," encompassing <span class="hlt">wave</span> power, <span class="hlt">wave</span> potential, and <span class="hlt">wave</span> separation of hydraulic power provides a potent time-domain approach for analyzing hemodynamics. Copyright © 2016 the American Physiological Society.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14734631','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14734631"><span>Hydrogen sulfide <span class="hlt">induces</span> calcium <span class="hlt">waves</span> in astrocytes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nagai, Yasuo; Tsugane, Mamiko; Oka, Jun-Ichiro; Kimura, Hideo</p> <p>2004-03-01</p> <p>Hydrogen sulfide (H2S) modifies hippocampal long-term potentiation (LTP) and functions as a neuromodulator. Here, we show that H2S increases intracellular Ca2+ and <span class="hlt">induces</span> Ca2+ <span class="hlt">waves</span> in primary cultures of astrocytes as well as hippocampal slices. H2S increases the influx of Ca2+ and to a lesser extent causes the release from intracellular Ca2+ stores. Ca2+ <span class="hlt">waves</span> <span class="hlt">induced</span> by neuronal excitation as well as responses to exogenously applied H2S are potently blocked by La3+ and Gd3+, inhibitors of Ca2+ channels. These observations suggest that H2S <span class="hlt">induces</span> Ca2+ <span class="hlt">waves</span> that propagate to neighboring astrocytes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1987JGR....9211979R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1987JGR....9211979R"><span>Air <span class="hlt">pressure</span> <span class="hlt">waves</span> from Mount St. Helens eruptions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reed, Jack W.</p> <p>1987-10-01</p> <p>Infrasonic recordings of the <span class="hlt">pressure</span> <span class="hlt">wave</span> from the Mount St. Helens (MSH) eruption on May 18, 1980, together with the weather station barograph records were used to estimate an equivalent explosion airblast yield for this eruption. <span class="hlt">Pressure</span> <span class="hlt">wave</span> amplitudes versus distance patterns were found to be comparable with patterns found for a small-scale nuclear explosion, the Krakatoa eruption, and the Tunguska comet impact, indicating that the MSH <span class="hlt">wave</span> came from an explosion equivalent of about 5 megatons of TNT. The peculiar audibility pattern reported, with the blast being heard only at ranges beyond about 100 km, is explained by consideration of finite-amplitude shock propagation developments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1983STIN...8415446E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1983STIN...8415446E"><span>Characterization of the <span class="hlt">pressure</span> <span class="hlt">wave</span> originating in the explosion of a gas cloud</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Essers, J. A.</p> <p></p> <p>Models for predicting the effects of hydrocarbon explosions on nuclear power plants are discussed. By solving the Euler equations for simple one dimensional models, formulas predicting <span class="hlt">wave</span> speed, <span class="hlt">induced</span> flow velocity, reflected <span class="hlt">wave</span> speed and overpressure as functions of the local value of incident <span class="hlt">wave</span> overpressure are obtained. A simplified nonlinear isentropic potential flow model is proposed. Errors in predicting <span class="hlt">wave</span> characteristics from this model or from classical linear acoustic models are evaluated. Formulas to predict the evolution of main <span class="hlt">pressure</span> pulse characteristics are given. The time and distance required for the formation of a sharp <span class="hlt">pressure</span> pulse and to obtain a significant spreading of expansion phase is assessed. The ability of models to accurately predict these deformations is discussed. The isentropic model leads to an excellent prediction of all <span class="hlt">wave</span> characteristics if the overpressure is not very large. Except for very weak overpressures, the accuracy of acoustic models is poor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988CPL...144..515M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988CPL...144..515M"><span>Oscillatory hydrodynamic flow <span class="hlt">induced</span> by chemical <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Miike, Hidetoshi; Müller, Stefan C.; Hess, Benno</p> <p>1988-05-01</p> <p>Hydrodynamic flows in a reactive liquid <span class="hlt">induced</span> by the propagation of <span class="hlt">waves</span> of chemical activity are investigated for the ferroin-catalyzed Belousov-Zhabotinskii reaction in thin layers by microscope video imaging techniques. The motion of added polystyrene spheres is observed with laser light illumination. Oscillations in the hydrodynamic flow were detected in rotating spiral <span class="hlt">waves</span> with an open liquid/gas interface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880013800','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880013800"><span>Initial condition effect on <span class="hlt">pressure</span> <span class="hlt">waves</span> in an axisymmetric jet</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Miles, Jeffrey H.; Raman, Ganesh</p> <p>1988-01-01</p> <p>A pair of microphones (separated axially by 5.08 cm and laterally by 1.3 cm) are placed on either side of the jet centerline to investigate coherent <span class="hlt">pressure</span> fluctuations in an axisymmetric jet at Strouhal numbers less than unity. Auto-spectra, transfer-function, and coherence measurements are made for a tripped and untripped boundary layer initial condition. It was found that coherent acoustic <span class="hlt">pressure</span> <span class="hlt">waves</span> originating in the upstream plenum chamber propagate a greater distance downstream for the tripped initial condition than for the untripped initial condition. In addition, for the untripped initial condition the development of the coherent hydrodynamic <span class="hlt">pressure</span> <span class="hlt">waves</span> shifts downstream.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3018759','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3018759"><span>Distal Shift of Arterial <span class="hlt">Pressure</span> <span class="hlt">Wave</span> Reflection Sites with Aging</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Sugawara, Jun; Hayashi, Koichiro; Tanaka, Hirofumi</p> <p>2010-01-01</p> <p>An early return of reflected <span class="hlt">waves</span>, the backward propagation of the arterial <span class="hlt">pressure</span> <span class="hlt">wave</span> from the periphery to the heart, is associated with the augmentation of central pulse <span class="hlt">pressure</span> and cardiovascular risks. The location of arterial <span class="hlt">pressure</span> <span class="hlt">wave</span> reflection, along with arterial stiffening, have a major influence on the timing of the reflected <span class="hlt">wave</span>. To determine the influence of aging on the location of a major reflection site, arterial length (via three-dimensional artery tracing of magnetic resonance imaging) and central (carotid-femoral) and peripheral (femoral-ankle) pulse <span class="hlt">wave</span> velocity were measured in 208 adults varying in age. The major reflection site was detected by carotid-femoral pulse <span class="hlt">wave</span> velocity and the reflected <span class="hlt">wave</span> transit time (via carotid arterial <span class="hlt">pressure</span> <span class="hlt">wave</span> analysis). The length from the aortic valve to the major reflection site (e.g., effective reflecting length) significantly increased with aging. The effective reflecting length normalized by the arterial length demonstrated that the major reflection sites located between the aortic bifurcation and femoral site in most of the subjects. The normalized effective reflecting length did not alter with aging until 65-year-old and increased remarkably thereafter in men and women. The effective reflecting length was significantly and positively associated with the difference between central and peripheral pulse <span class="hlt">wave</span> velocity (r=0.76). This correlation remained significant even when the influence of aortic pulse <span class="hlt">wave</span> velocity was partial out (r=0.35). These results suggest that the major reflection site shifts distally with aging partly due to the closer matching of impedance provided by central and peripheral arterial stiffness. PMID:20876449</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009APS..DFD.LS002D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009APS..DFD.LS002D"><span>An Experimental Investigation of the <span class="hlt">Wave</span> Pattern Generated by a Moving <span class="hlt">Pressure</span> Source: Solitary Capillary-Gravity <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Duncan, J. H.; Diorio, J. D.; Lisiewski, A.; Harris, R.</p> <p>2009-11-01</p> <p>The <span class="hlt">wave</span> pattern generated by a small <span class="hlt">pressure</span> source moving across a water surface at speeds less than the minimum phase speed for linear gravity-capillary <span class="hlt">waves</span> (cmin = 23 cm/s) was investigated experimentally. The resulting <span class="hlt">wave</span> pattern was measured using cinematic shadowgraph and laser-<span class="hlt">induced</span> fluorescence (LIF) techniques. The results show the existence of several distinct behavioral states. At low speeds, no <span class="hlt">wave</span> behavior is observed and the pattern resembles the symmetric stationary condition. However, at a critical speed, but still below cmin, the pattern undergoes a sudden transition to an asymmetric state with a stationary, 2D solitary <span class="hlt">wave</span> that forms behind the <span class="hlt">pressure</span> source. This solitary <span class="hlt">wave</span> is elongated in the cross-stream relative to the stream-wise direction and resembles gravity-capillary ``lumps'' observed in previous numerical calculations. As the translation speed approaches cmin, another time-dependent behavior is observed characterized by periodic ``shedding'' from a V-shaped solitary <span class="hlt">wave</span> pattern. This work will be discussed in conjunction with the recent numerical calculations of T. Akylas and his research group.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16797665','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16797665"><span>Acoustic <span class="hlt">wave</span> propagation in high-<span class="hlt">pressure</span> system.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Foldyna, Josef; Sitek, Libor; Habán, Vladimír</p> <p>2006-12-22</p> <p>Recently, substantial attention is paid to the development of methods of generation of pulsations in high-<span class="hlt">pressure</span> systems to produce pulsating high-speed water jets. The reason is that the introduction of pulsations into the water jets enables to increase their cutting efficiency due to the fact that the impact <span class="hlt">pressure</span> (so-called water-hammer <span class="hlt">pressure</span>) generated by an impact of slug of water on the target material is considerably higher than the stagnation <span class="hlt">pressure</span> generated by corresponding continuous jet. Special method of pulsating jet generation was developed and tested extensively under the laboratory conditions at the Institute of Geonics in Ostrava. The method is based on the action of acoustic transducer on the <span class="hlt">pressure</span> liquid and transmission of generated acoustic <span class="hlt">waves</span> via <span class="hlt">pressure</span> system to the nozzle. The purpose of the paper is to present results obtained during the research oriented at the determination of acoustic <span class="hlt">wave</span> propagation in high-<span class="hlt">pressure</span> system. The final objective of the research is to solve the problem of transmission of acoustic <span class="hlt">waves</span> through high-<span class="hlt">pressure</span> water to generate pulsating jet effectively even at larger distances from the acoustic source. In order to be able to simulate numerically acoustic <span class="hlt">wave</span> propagation in the system, it is necessary among others to determine dependence of the sound speed and second kinematical viscosity on operating <span class="hlt">pressure</span>. Method of determination of the second kinematical viscosity and speed of sound in liquid using modal analysis of response of the tube filled with liquid to the impact was developed. The response was measured by <span class="hlt">pressure</span> sensors placed at both ends of the tube. Results obtained and presented in the paper indicate good agreement between experimental data and values of speed of sound calculated from so-called "UNESCO equation". They also show that the value of the second kinematical viscosity of water depends on the <span class="hlt">pressure</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25561452','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25561452"><span>Quantification of <span class="hlt">wave</span> reflection using peripheral blood <span class="hlt">pressure</span> waveforms.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kim, Chang-Sei; Fazeli, Nima; McMurtry, M Sean; Finegan, Barry A; Hahn, Jin-Oh</p> <p>2015-01-01</p> <p>This paper presents a novel minimally invasive method for quantifying blood <span class="hlt">pressure</span> (BP) <span class="hlt">wave</span> reflection in the arterial tree. In this method, two peripheral BP waveforms are analyzed to obtain an estimate of central aortic BP waveform, which is used together with a peripheral BP waveform to compute forward and backward <span class="hlt">pressure</span> <span class="hlt">waves</span>. These forward and backward <span class="hlt">waves</span> are then used to quantify the strength of <span class="hlt">wave</span> reflection in the arterial tree. Two unique strengths of the proposed method are that 1) it replaces highly invasive central aortic BP and flow waveforms required in many existing methods by less invasive peripheral BP waveforms, and 2) it does not require estimation of characteristic impedance. The feasibility of the proposed method was examined in an experimental swine subject under a wide range of physiologic states and in 13 cardiac surgery patients. In the swine subject, the method was comparable to the reference method based on central aortic BP and flow. In cardiac surgery patients, the method was able to estimate forward and backward <span class="hlt">pressure</span> <span class="hlt">waves</span> in the absence of any central aortic waveforms: on the average, the root-mean-squared error between actual versus computed forward and backward <span class="hlt">pressure</span> <span class="hlt">waves</span> was less than 5 mmHg, and the error between actual versus computed reflection index was less than 0.03.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AIPC.1218..695C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AIPC.1218..695C"><span>Diaphragm <span class="hlt">Pressure</span> <span class="hlt">Wave</span> Generator Developments at Industrial Research Ltd</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caughley, A. J.; Emery, N.; Glasson, N. D.</p> <p>2010-04-01</p> <p>Industrial Research Ltd (IRL) have been developing a unique diaphragm based <span class="hlt">pressure</span> <span class="hlt">wave</span> generator technology for pulse tube and Stirling cryocoolers. Our system uses a metal diaphragm to separate the clean cryocooler gas circuit from a conventionally lubricated mechanical driver, thus producing a clean <span class="hlt">pressure</span> <span class="hlt">wave</span> with a long life drive that does not require the precision manufacture and associated costs of large linear motors. The first successful diaphragm <span class="hlt">pressure</span> <span class="hlt">wave</span> generator produced 3.2 kW of acoustic power at an electro-acoustic efficiency of 72% with a swept volume of 200 ml and a prototype has now accumulated over 2500 hours running. This paper describes recent developments in the technology. To explore scaling, a small diaphragm <span class="hlt">pressure</span> <span class="hlt">wave</span> generator with a swept volume of 20 ml has been constructed and has delivered 454 W of acoustic power at an electro-acoustic efficiency of 60%. Improvements have been made to the hydraulic force amplifier mechanism for driving the diaphragms resulting in a cheaper and lighter mechanism than the mechanical linkage originally used. To meet a customer's specific requirements, the 200 ml <span class="hlt">pressure</span> <span class="hlt">wave</span> generator's stroke was extended to achieve 240 ml of swept volume thereby increasing its acoustic power delivery to 4.1 kW without compromising efficiency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AIPC.1573.1424C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AIPC.1573.1424C"><span>30 kW metal diaphragm <span class="hlt">pressure</span> <span class="hlt">wave</span> generator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caughley, A.; Branje, P.; Klok, T.</p> <p>2014-01-01</p> <p>Callaghan Innovation has been developing a metal-diaphragm <span class="hlt">pressure</span> <span class="hlt">wave</span> generator technology for pulse tube or Stirling cryocoolers since 2005. A series of successful <span class="hlt">pressure</span> <span class="hlt">wave</span> generators have been designed, fabricated and demonstrated ranging in swept volume from 20 to 240 cc driven by commercially available induction motors of powers from 0.5 kW to 7.5 kW respectively. A number of pulse tubes have also been design and successfully trialed with these <span class="hlt">pressure</span> <span class="hlt">wave</span> generators. Cooling powers up to 600 W at 120 K have been achieved. We have now scaled the <span class="hlt">pressure</span> <span class="hlt">wave</span> generator technology to 1000cc swept volume, powered by a 30 kW induction motor with the intention of providing over 20 kW of acoustic power to either pulse tube or Stirling expanders. The aim is to develop a cryocooler with more than 1000 W of refrigeration at 77 K. Target applications include liquefaction and High Temperature Superconducting devices. Initial results from testing the 1000 cc <span class="hlt">pressure</span> <span class="hlt">wave</span> generator are presented and we will discuss the challenges and advantages involved in scaling the metal diaphragm technology to higher acoustic powers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ApPhL.105k3507M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ApPhL.105k3507M"><span>Dual mode acoustic <span class="hlt">wave</span> sensor for precise <span class="hlt">pressure</span> reading</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mu, Xiaojing; Kropelnicki, Piotr; Wang, Yong; Randles, Andrew Benson; Chuan Chai, Kevin Tshun; Cai, Hong; Gu, Yuan Dong</p> <p>2014-09-01</p> <p>In this letter, a Microelectromechanical system acoustic <span class="hlt">wave</span> sensor, which has a dual mode (lateral field exited Lamb <span class="hlt">wave</span> mode and surface acoustic <span class="hlt">wave</span> (SAW) mode) behavior, is presented for precious <span class="hlt">pressure</span> change read out. Comb-like interdigital structured electrodes on top of piezoelectric material aluminium nitride (AlN) are used to generate the <span class="hlt">wave</span> modes. The sensor membrane consists of single crystalline silicon formed by backside-etching of the bulk material of a silicon on insulator wafer having variable device thickness layer (5 μm-50 μm). With this principle, a <span class="hlt">pressure</span> sensor has been fabricated and mounted on a <span class="hlt">pressure</span> test package with <span class="hlt">pressure</span> applied to the backside of the membrane within a range of 0 psi to 300 psi. The temperature coefficient of frequency was experimentally measured in the temperature range of -50 °C to 300 °C. This idea demonstrates a piezoelectric based sensor having two modes SAW/Lamb <span class="hlt">wave</span> for direct physical parameter—<span class="hlt">pressure</span> readout and temperature cancellation which can operate in harsh environment such as oil and gas exploration, automobile and aeronautic applications using the dual mode behavior of the sensor and differential readout at the same time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030068126','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030068126"><span>Acoustic <span class="hlt">Wave</span> Propagation in <span class="hlt">Pressure</span> Sense Lines</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Vitarius, Patrick; Gregory, Don A.; Wiley, John; Korman, Valentin</p> <p>2003-01-01</p> <p>Sense lines are used in <span class="hlt">pressure</span> measurements to passively transmit information from hostile environments to areas where transducers can be used. The transfer function of a sense line can be used to obtain information about the measured environment from the protected sensor. Several properties of this transfer function are examined, including frequency dependence, Helmholtz resonance, and time of flight delay.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22403108','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22403108"><span><span class="hlt">Induced</span> topological <span class="hlt">pressure</span> for topological dynamical systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xing, Zhitao; Chen, Ercai</p> <p>2015-02-15</p> <p>In this paper, inspired by the article [J. Jaerisch et al., Stochastics Dyn. 14, 1350016, pp. 1-30 (2014)], we introduce the <span class="hlt">induced</span> topological <span class="hlt">pressure</span> for a topological dynamical system. In particular, we prove a variational principle for the <span class="hlt">induced</span> topological <span class="hlt">pressure</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/495732','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/495732"><span>Propagation velocity and reflection of <span class="hlt">pressure</span> <span class="hlt">waves</span> in the canine coronary artery.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Arts, T; Kruger, R T; van Gerven, W; Lambregts, J A; Reneman, R S</p> <p>1979-10-01</p> <p>In this study the <span class="hlt">pressure</span> <span class="hlt">wave</span> velocity in the anterior descending branch of the left coronary artery (LADC) of the dog was measured by determining the delay time between <span class="hlt">pressure</span> pulses along this artery. This method can only be applied if reflections of the <span class="hlt">pressure</span> <span class="hlt">wave</span> distal to the sites of <span class="hlt">pressure</span> measurement are insignificant. From araldite casts of the coronary arteries the following relation between the diameter proximal to (dprox) and distal to (ddist 1, ddist 2) a bifurcation was found: dprox2.55 = ddist12.55 + ddist 22.55, indicating that reflections at a bifurcation areminimal. In dogs reflections were studied by <span class="hlt">inducing</span> during diastole a <span class="hlt">pressure</span> pulse in the aorta and measuring <span class="hlt">pressure</span> and volume flow proximal to and <span class="hlt">pressure</span> distal to a segment of the LADC at various levels of the coronary peripheral resistance. Reflection of high-frequency components (greater than 7 Hz) was found to be insignificant, allowing application of the above-mentioned method for measuring the <span class="hlt">wave</span>-front velocity, which is insensitive to low-frequency reflection. At a <span class="hlt">pressure</span> in the LADC of 13.3 kPa this velocity was 8.6 +/- 1.4 m.s-1 (mean +/- SD). The calculated dynamic cross-sectional stiffness (deltaP/(deltaA/A)) of the LADC was 97 +/- 11 kPa (mean +/- SE) at an arterial <span class="hlt">pressure</span> of 13.3 kPa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/7226865','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/7226865"><span>Cerebral perfusion <span class="hlt">pressure</span> and abnormal intracranial <span class="hlt">pressure</span> <span class="hlt">wave</span> forms: their relation to outcome in birth asphyxia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Raju, T N; Vidyasagar, D; Papazafiratou, C</p> <p>1981-06-01</p> <p>Intracranial <span class="hlt">pressure</span> (ICP) studies were carried out in 14 infants with severe birth asphyxia and brain damage. A markedly low cerebral perfusion <span class="hlt">pressure</span> (CPP) was noted in infants who died and in 1 infant who survived with cerebral palsy. The long-term ICP tracing revealed negative <span class="hlt">waves</span> and plateau <span class="hlt">waves</span> in 2 infants. Cushing response was noted in 2 infants who had elevated ICP. The value and significance of evaluated CPP and of abnormal waveforms are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1987DSJ....37..383S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1987DSJ....37..383S"><span>Generation of high <span class="hlt">pressure</span> and temperature by converging detonation <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singh, V. P.; Shukla, S. K.</p> <p>1987-07-01</p> <p>Generation of high <span class="hlt">pressure</span> and temperature has various applications in defense. Several techniques, viz flying plate method, collapsing of linear, convergence of detonation <span class="hlt">waves</span> in solid explosives, have been established in this connection. In this paper, converging detonation <span class="hlt">waves</span> in solid explosives, where variable heat of detonation is being added to the front, are studied by using Whitham's characteristics rule. Results are compared with those reported elsewhere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11847333','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11847333"><span>X-ray imaging of shock <span class="hlt">waves</span> generated by high-<span class="hlt">pressure</span> fuel sprays.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>MacPhee, Andrew G; Tate, Mark W; Powell, Christopher F; Yue, Yong; Renzi, Matthew J; Ercan, Alper; Narayanan, Suresh; Fontes, Ernest; Walther, Jochen; Schaller, Johannes; Gruner, Sol M; Wang, Jin</p> <p>2002-02-15</p> <p>Synchrotron x-radiography and a fast x-ray detector were used to record the time evolution of the transient fuel sprays from a high-<span class="hlt">pressure</span> injector. A succession of 5.1-microsecond radiographs captured the propagation of the spray-<span class="hlt">induced</span> shock <span class="hlt">waves</span> in a gaseous medium and revealed the complex nature of the spray hydrodynamics. The monochromatic x-radiographs also allow quantitative analysis of the shock <span class="hlt">waves</span> that has been difficult if not impossible with optical imaging. Under injection conditions similar to those found in operating engines, the fuel jets can exceed supersonic speeds and result in gaseous shock <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26206527','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26206527"><span>Ultrasonic <span class="hlt">wave</span> based <span class="hlt">pressure</span> measurement in small diameter pipeline.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Dan; Song, Zhengxiang; Wu, Yuan; Jiang, Yuan</p> <p>2015-12-01</p> <p>An effective non-intrusive method of ultrasound-based technique that allows monitoring liquid <span class="hlt">pressure</span> in small diameter pipeline (less than 10mm) is presented in this paper. Ultrasonic <span class="hlt">wave</span> could penetrate medium, through the acquisition of representative information from the echoes, properties of medium can be reflected. This <span class="hlt">pressure</span> measurement is difficult due to that echoes' information is not easy to obtain in small diameter pipeline. The proposed method is a study on pipeline with Kneser liquid and is based on the principle that the transmission speed of ultrasonic <span class="hlt">wave</span> in pipeline liquid correlates with liquid <span class="hlt">pressure</span> and transmission speed of ultrasonic <span class="hlt">wave</span> in pipeline liquid is reflected through ultrasonic propagation time providing that acoustic distance is fixed. Therefore, variation of ultrasonic propagation time can reflect variation of <span class="hlt">pressure</span> in pipeline. Ultrasonic propagation time is obtained by electric processing approach and is accurately measured to nanosecond through high resolution time measurement module. We used ultrasonic propagation time difference to reflect actual <span class="hlt">pressure</span> in this paper to reduce the environmental influences. The corresponding <span class="hlt">pressure</span> values are finally obtained by acquiring the relationship between variation of ultrasonic propagation time difference and <span class="hlt">pressure</span> with the use of neural network analysis method, the results show that this method is accurate and can be used in practice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AIPC.1770c0114K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AIPC.1770c0114K"><span>Hydrodynamic <span class="hlt">pressure</span> of breaking <span class="hlt">waves</span> on buildings and their interaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kashevarova, G. G.; Martirosyan, A. S.</p> <p>2016-10-01</p> <p>In the course of numerical experiments the problem hydrodynamic <span class="hlt">pressure</span> of breaking <span class="hlt">waves</span> on buildings and their interaction was solved in a related setting, e.g. fluid flow and deformation of the building were calculated simultaneously. The method of calculation allows evaluating the dependence of the hydrodynamic <span class="hlt">pressure</span> of water flow from the shape of the building in plan, size and orientation relative to the direction of flow stream. This study allowed to perform strength analysis of buildings under the action of breakthrough <span class="hlt">wave</span> for evaluate the necessity of guard measures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890046357&hterms=1087&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3D%2526%25231087','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890046357&hterms=1087&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3D%2526%25231087"><span>Acoustic <span class="hlt">waves</span> in gases with strong <span class="hlt">pressure</span> gradients</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zorumski, William E.</p> <p>1989-01-01</p> <p>The effect of strong <span class="hlt">pressure</span> gradients on the acoustic modes (standing <span class="hlt">waves</span>) of a rectangular cavity is investigated analytically. When the cavity response is represented by a sum of modes, each mode is found to have two resonant frequencies. The lower frequency is near the Viaesaela-Brundt frequency, which characterizes the buoyant effect, and the higher frequency is above the ordinary acoustic resonance frequency. This finding shows that the propagation velocity of the acoustic <span class="hlt">waves</span> is increased due to the <span class="hlt">pressure</span> gradient effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013OptLE..51..134Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013OptLE..51..134Z"><span>Rapid miniature fiber optic <span class="hlt">pressure</span> sensors for blast <span class="hlt">wave</span> measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zou, Xiaotian; Wu, Nan; Tian, Ye; Niezrecki, Christopher; Chen, Julie; Wang, Xingwei</p> <p>2013-02-01</p> <p>Traumatic brain injury (TBI) is a serious potential threat to soldiers who are exposed to explosions. Since the pathophysiology of TBI associated with a blast <span class="hlt">wave</span> is not clearly defined, it is crucial to have a sensing system to accurately quantify the blast <span class="hlt">wave</span> dynamics. This paper presents an ultra-fast fiber optic <span class="hlt">pressure</span> sensor based on Fabry-Perot (FP) interferometric principle that is capable of measuring the rapid <span class="hlt">pressure</span> changes in a blast event. The blast event in the experiment was generated by a starter pistol blank firing at close range, which produced a more realistic <span class="hlt">wave</span> profile compared to using compressed air driven shock tubes. To the authors' knowledge, it is also the first study to utilize fiber optic <span class="hlt">pressure</span> sensors to measure the ballistics shock <span class="hlt">wave</span> of a pistol firing. The results illustrated that the fiber optic <span class="hlt">pressure</span> sensor has a rise time of 200 ns which demonstrated that the sensor has ability to capture the dynamic <span class="hlt">pressure</span> transient during a blast event. Moreover, the resonant frequency of the sensor was determined to be 4.11 MHz, which agrees well with the specific designed value.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988CG.....14..641D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988CG.....14..641D"><span>An APL function for modeling p-<span class="hlt">wave</span> <span class="hlt">induced</span> liquefaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Doehring, Donald O.; Charlie, Wayne A.; Veyera, George E.</p> <p></p> <p>This paper presents an APL function that models particle acceleration, velocity, displacement, and porewater <span class="hlt">pressure</span> responses <span class="hlt">induced</span> by the passage of compressional <span class="hlt">waves</span> through water-saturated soil. Inputs to the function include: mass of soil elements, boundary conditions, spring constants, damping ratio, forces applied to the first element, threshold strain and a time increment. Output closely approximates the results of laboratory and field measurements of this phenomenon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27278507','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27278507"><span>Influence of general anaesthesia on slow <span class="hlt">waves</span> of intracranial <span class="hlt">pressure</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lalou, Despina A; Czosnyka, Marek; Donnelly, Joseph; Lavinio, Andrea; Pickard, John D; Garnett, Matthew; Czosnyka, Zofia</p> <p>2016-07-01</p> <p>Slow vasogenic intracranial <span class="hlt">pressure</span> (ICP) <span class="hlt">waves</span> are spontaneous ICP oscillations with a low frequency bandwidth of 0.3-4 cycles/min (B-<span class="hlt">waves</span>). B-<span class="hlt">waves</span> reflect dynamic oscillations in cerebral blood volume associated with autoregulatory cerebral vasodilation and vasoconstriction. This study quantifies the effects of general anaesthesia (GA) on the magnitude of B-<span class="hlt">waves</span> compared to natural sleep and conscious state. The magnitude of B-<span class="hlt">waves</span> was assessed in 4 groups of 30 patients each with clinical indications for ICP monitoring. Normal <span class="hlt">pressure</span> hydrocephalus patients undergoing Cerebrospinal Fluid (CSF) infusion studies in the conscious state (GROUP A) and under GA (GROUP B), and hydrocephalus patients undergoing overnight ICP monitoring during physiological sleep (GROUP C) were compared to deeply sedated traumatic brain injury (TBI) patients with well-controlled ICP during the first night of Intensive Care Unit (ICU) stay (GROUP D). A total of 120 patients were included. During CSF infusion studies, the magnitude of slow <span class="hlt">waves</span> was higher in conscious patients ( 0.23+/-0.10 mm Hg) when compared to anaesthetised patients ( 0.15+/-0.10 mm Hg; p = 0.011). Overnight magnitude of slow <span class="hlt">waves</span> was higher in patients during natural sleep (GROUP C: 0.20+/-0.13 mm Hg) when compared to TBI patients under deep sedation (GROUP D: 0.11+/- 0.09 mm Hg; p = 0.002). GA and deep sedation are associated with a reduced magnitude of B-<span class="hlt">waves</span>. ICP monitoring carried out under GA is affected by iatrogenic suppression of slow vasogenic <span class="hlt">waves</span> of ICP. Accounting for the effects of anaesthesia on vasogenic <span class="hlt">waves</span> may prevent the misidentification of potential shunt-responders as non-responders.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008EPJB...66..419B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008EPJB...66..419B"><span>Two-phase flow model for energetic proton beam <span class="hlt">induced</span> <span class="hlt">pressure</span> <span class="hlt">waves</span> in mercury target systems in the planned European Spallation Source</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barna, I. F.; Imre, A. R.; Rosta, L.; Mezei, F.</p> <p>2008-12-01</p> <p>Two-phase flow calculations are presented to investigate the thermo-hydraulical effects of the interaction between 2 ms long 1.3 GeV proton pulses with a closed mercury loop which can be considered as a model system of the target of the planned European Spallation Source (ESS) facility. The two-fluid model consists of six first-order partial differential equations that present one dimensional mass, momentum and energy balances for mercury vapor and liquid phases are capable to describe quick transients like cavitation effects or shock <span class="hlt">waves</span>. The absorption of the proton beam is represented as instantaneous heat source in the energy balance equations. Densities and internal energies of the mercury liquid-vapor system is calculated from the van der Waals equation, but general method how to obtain such properties using arbitrary equation of state is also presented. A second order accurate high-resolution shock-capturing numerical scheme is applied with different kind of limiters in the numerical calculations. Our analysis show that even 75 degree temperature heat shocks cannot cause considerable cavitation effects in mercury.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5554744','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5554744"><span>Air <span class="hlt">pressure</span> <span class="hlt">waves</span> from Mount St. Helens eruptions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Reed, J.W.</p> <p>1987-10-20</p> <p>Weather station barograph records as well as infrasonic recordings of the <span class="hlt">pressure</span> <span class="hlt">wave</span> from the Mount St. Helens eruption of May 18, 1980, have been used to estimate an equivalent explosion airblast yield for this event. <span class="hlt">Pressure</span> amplitude versus distance patterns in various directions compared with patterns from other large explosions, such as atmospheric nuclear tests, the Krakatoa eruption, and the Tunguska comet impact, indicate that the <span class="hlt">wave</span> came from an explosion equivalent of a few megatons of TNT. The extent of tree blowdown is considerably greater than could be expected from such an explosion, and the observed forest damage is attributed to outflow of volcanic material. The <span class="hlt">pressure</span>-time signature obtained at Toledo, Washington, showed a long, 13-min duration negative phase as well as a second, hour-long compression phase, both probably caused by ejacta dynamics rather than standard explosion <span class="hlt">wave</span> phenomenology. The peculiar audibility pattern, with the blast being heard only at ranges beyond about 100 km, is explicable by finite amplitude propagation effects. Near the source, compression was slow, taking more than a second but probably less than 5 s, so that it went unnoticed by human ears and susceptible buildings were not damaged. There was no damage as Toledo (54 km), where the recorded amplitude would have broken windows with a fast compression. An explanation is that <span class="hlt">wave</span> emissions at high elevation angles traveled to the upper stratosphere, where low ambient air <span class="hlt">pressures</span> caused this energetic <span class="hlt">pressure</span> oscillation to form a shock <span class="hlt">wave</span> with rapid, nearly instantaneous compression. Atmospheric refraction then returned part of this <span class="hlt">wave</span> to ground level at long ranges, where the fast compressions were clearly audible. copyright American Geophysical Union 1987</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28714892','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28714892"><span>Passive Downhole <span class="hlt">Pressure</span> Sensor Based on Surface Acoustic <span class="hlt">Wave</span> Technology.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Quintero, Sully M M; Figueiredo, Sávio W O; Takahashi, Victor L; Llerena, Roberth A W; Braga, Arthur M B</p> <p>2017-07-15</p> <p>A passive surface acoustic <span class="hlt">wave</span> (SAW) <span class="hlt">pressure</span> sensor was developed for real-time <span class="hlt">pressure</span> monitoring in downhole application. The passive <span class="hlt">pressure</span> sensor consists of a SAW resonator, which is attached to a circular metal diaphragm used as a <span class="hlt">pressure</span> transducer. While the membrane deflects as a function of <span class="hlt">pressure</span> applied, the frequency response changes due to the variation of the SAW propagation parameters. The sensitivity and linearity of the SAW <span class="hlt">pressure</span> sensor were measured to be 8.3 kHz/bar and 0.999, respectively. The experimental results were validated with a hybrid analytical-numerical analysis. The good results combined with the robust design and packaging for harsh environment demonstrated it to be a promising sensor for industrial applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870000350&hterms=eve&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Deve','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870000350&hterms=eve&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Deve"><span>Reduction of Orifice-<span class="hlt">Induced</span> <span class="hlt">Pressure</span> Errors</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Plentovich, Elizabeth B.; Gloss, Blair B.; Eves, John W.; Stack, John P.</p> <p>1987-01-01</p> <p>Use of porous-plug orifice reduces or eliminates errors, <span class="hlt">induced</span> by orifice itself, in measuring static <span class="hlt">pressure</span> on airfoil surface in wind-tunnel experiments. Piece of sintered metal press-fitted into static-<span class="hlt">pressure</span> orifice so it matches surface contour of model. Porous material reduces orifice-<span class="hlt">induced</span> <span class="hlt">pressure</span> error associated with conventional orifice of same or smaller diameter. Also reduces or eliminates additional errors in <span class="hlt">pressure</span> measurement caused by orifice imperfections. Provides more accurate measurements in regions with very thin boundary layers.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25501688','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25501688"><span>Changes in Cerebral Partial Oxygen <span class="hlt">Pressure</span> and Cerebrovascular Reactivity During Intracranial <span class="hlt">Pressure</span> Plateau <span class="hlt">Waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lang, Erhard W; Kasprowicz, Magdalena; Smielewski, Peter; Pickard, John; Czosnyka, Marek</p> <p>2015-08-01</p> <p>Plateau <span class="hlt">waves</span> in intracranial <span class="hlt">pressure</span> (ICP) are frequently recorded in neuro intensive care and are not yet fully understood. To further investigate this phenomenon, we analyzed partial <span class="hlt">pressure</span> of cerebral oxygen (pbtO2) and a moving correlation coefficient between ICP and mean arterial blood <span class="hlt">pressure</span> (ABP), called PRx, along with the cerebral oxygen reactivity index (ORx), which is a moving correlation coefficient between cerebral perfusion <span class="hlt">pressure</span> (CPP) and pbtO2 in an observational study. We analyzed 55 plateau <span class="hlt">waves</span> in 20 patients after severe traumatic brain injury. We calculated ABP, ABP pulse amplitude (ampABP), ICP, CPP, pbtO2, heart rate (HR), ICP pulse amplitude (ampICP), PRx, and ORx, before, during, and after each plateau <span class="hlt">wave</span>. The analysis of variance with Bonferroni post hoc test was used to compare the differences in the variables before, during, and after the plateau <span class="hlt">wave</span>. We considered all plateau <span class="hlt">waves</span>, even in the same patient, independent because they are separated by long intervals. We found increases for ICP and ampICP according to our operational definitions for plateau <span class="hlt">waves</span>. PRx increased significantly (p = 0.00026), CPP (p < 0.00001) and pbtO2 (p = 0.00007) decreased significantly during the plateau <span class="hlt">waves</span>. ABP, ampABP, and HR remained unchanged. PRx during the plateau was higher than before the onset of <span class="hlt">wave</span> in 40 cases (73 %) with no differences in baseline parameters for those with negative and positive ΔPRx (difference during and after). ORx showed an increase during and a decrease after the plateau <span class="hlt">waves</span>, however, not statistically significant. PbtO2 overshoot after the <span class="hlt">wave</span> occurred in 35 times (64 %), the mean difference was 4.9 ± 4.6 Hg (mean ± SD), and we found no difference in baseline parameters between those who overshoot and those who did not overshoot. Arterial blood <span class="hlt">pressure</span> remains stable in ICP plateau <span class="hlt">waves</span>, while cerebral autoregulatory indices show distinct changes, which indicate cerebrovascular</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19740051611&hterms=qualitative+characteristics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dqualitative%2Bcharacteristics','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19740051611&hterms=qualitative+characteristics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dqualitative%2Bcharacteristics"><span>Attenuation characteristics of nonlinear <span class="hlt">pressure</span> <span class="hlt">waves</span> propagating in pipes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shih, C. C.</p> <p>1974-01-01</p> <p>A series of experiments was conducted to investigate temporal and spatial velocity distributions of fluid flow in 3-in. open-end pipes of various lengths up to 210 ft, produced by the propagation of nonlinear <span class="hlt">pressure</span> <span class="hlt">waves</span> of various intensities. Velocity profiles across each of five sections along the pipes were measured as a function of time with the use of hot-film and hot-wire anemometers for two <span class="hlt">pressure</span> <span class="hlt">waves</span> produced by a piston. Peculiar configurations of the velocity profiles across the pipe section were noted, which are uncommon for steady pipe flow. Theoretical consideration was given to this phenomenon of higher velocity near the pipe wall for qualitative confirmation. Experimentally time-dependent velocity distributions along the pipe axis were compared with one-dimensional theoretical results obtained by the method of characteristics with or without diffusion term for the purpose of determining the attenuation characteristics of the nonlinear <span class="hlt">wave</span> propagation in the pipes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770017362','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770017362"><span>Measurement of Blast <span class="hlt">Waves</span> from Bursting <span class="hlt">Pressureized</span> Frangible Spheres</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Esparza, E. D.; Baker, W. E.</p> <p>1977-01-01</p> <p>Small-scale experiments were conducted to obtain data on incident overpressure at various distances from bursting <span class="hlt">pressurized</span> spheres. Complete time histories of blast overpressure generated by rupturing glass spheres under high internal <span class="hlt">pressure</span> were obtained using eight side-on <span class="hlt">pressure</span> transducers. A scaling law is presented, and its nondimensional parameters are used to compare peak overpressures, arrival times, impulses, and durations for different initial conditions and sizes of blast source. The nondimensional data are also compared, whenever possible, with results of theoretical calculations and compiled data for Pentolite high explosive. The scaled data are repeatable and show significant differences from blast <span class="hlt">waves</span> generated by condensed high-explosives.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.4086K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.4086K"><span>Relationship between high-order non-linearity of random <span class="hlt">waves</span> and <span class="hlt">wave</span> <span class="hlt">pressures</span> acting on offshore breakwaters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kashima, Hiroaki</p> <p>2016-04-01</p> <p>In the design of breakwaters, the <span class="hlt">wave</span> <span class="hlt">pressures</span> out of the surf zone are estimated by the maximum <span class="hlt">wave</span> height which corresponds to the 1.8 times of significant <span class="hlt">wave</span> height according to Rayleigh theory. On the other hand, the nonlinear four-<span class="hlt">wave</span> interactions can lead to a significant enhancement of occurrence frequency of extreme <span class="hlt">waves</span> which have more than twice the significant <span class="hlt">wave</span> height. It is necessary to appropriately evaluate the effects of the deviation from Rayleigh theory on the <span class="hlt">wave</span> <span class="hlt">pressures</span> acting on offshore breakwaters under extreme <span class="hlt">wave</span> conditions. In this study, the physical experiments in a <span class="hlt">wave</span> tank were conducted to understand the effect of the occurrence frequency of the maximum <span class="hlt">wave</span> height on the <span class="hlt">wave</span> <span class="hlt">pressures</span> acting on offshore breakwaters. In our analysis, the <span class="hlt">wave</span> <span class="hlt">pressures</span> acting on breakwaters were estimated by using three kinds of the maximum <span class="hlt">wave</span> heights. The first and second are the maximum <span class="hlt">wave</span> height and the 1.8 times of significant <span class="hlt">wave</span> height obtained from the physical experiments. The last is the maximum <span class="hlt">wave</span> height given by the Japanese design method for breakwaters taking into account the nonlinear <span class="hlt">wave</span> shoaling effects. As a result, the occurrence frequency of the maximum <span class="hlt">wave</span> height given by the physical experiments is in a good agreement with the high-order nonlinear theory by Mori and Janssen (2006) and there is the deviation from the Rayleigh theory not only offshore but also in the intermediate depth. Moreover, the <span class="hlt">wave</span> <span class="hlt">pressures</span> using the maximum <span class="hlt">wave</span> height are widely distributed to the designed value of the <span class="hlt">wave</span> <span class="hlt">pressure</span> while the dispersion of the <span class="hlt">wave</span> <span class="hlt">pressures</span> using the 1.8 times of the significant <span class="hlt">wave</span> height is small. As the non-linearity of the <span class="hlt">waves</span> becomes stronger, the <span class="hlt">wave</span> <span class="hlt">pressures</span> tend to exceed the designed value of the <span class="hlt">wave</span> <span class="hlt">pressure</span> on the average through the behavior of the maximum <span class="hlt">wave</span> height depending on the kurtosis which is the indicator of the high-order nonlinear interactions. Finally, it is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880012120','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880012120"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> ageing of polymers</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Emri, I.; Knauss, W. G.</p> <p>1988-01-01</p> <p>The nonlinearly viscoelastic response of an amorphous homopolymer is considered under aspects of time dependent free volume behavior. In contrast to linearly viscoelastic solids, this model couples shear and volume deformation through a shift function which influences the rate of molecular relaxation or creep. Sample computations produce all those qualitative features one observes normally in uniaxial tension including the rate dependent formation of a yield point as a consequence of the history of an imposed <span class="hlt">pressure</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JGRC..11612004H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JGRC..11612004H"><span>Internal <span class="hlt">wave</span>-turbulence <span class="hlt">pressure</span> above sloping sea bottoms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Haren, Hans</p> <p>2011-12-01</p> <p>An accurate bottom <span class="hlt">pressure</span> sensor has been moored at different sites varying from a shallow sea strait via open ocean guyots to a 1900 m deep Gulf of Mexico. All sites show more or less sloping bottom topography. Focusing on frequencies (σ) higher than tidal, the <span class="hlt">pressure</span> records are remarkably similar, to within the 95% statistical significance bounds, in the internal gravity <span class="hlt">wave</span> continuum (IWC) band up to buoyancy frequency N. The IWC has a relatively uniform spectral slope: log(P(σ)) = -αlog(σ), α = 2 ± 1/3. The spectral collapse is confirmed from independent internal hydrostatic <span class="hlt">pressure</span> estimate, which suggests a saturated IWC. For σ > N, all <span class="hlt">pressure</span>-spectra transit to a bulge that differs in magnitude. This bulge is commonly attributed to long surface <span class="hlt">waves</span>. For the present data it is suggested to be due to stratified turbulence-internal <span class="hlt">wave</span> coupling, which is typically large over sloping topography. The bulge drops off at a more or less common frequency of 2-3 × 10-2 Hz, which is probably related with typical turbulent overturning scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800002736','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800002736"><span>Propagation of <span class="hlt">waves</span> in a medium with high radiation <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bisnovatyy-Kogan, G. S.; Blinnikov, S. I.</p> <p>1979-01-01</p> <p>The propagation and mutual transformation of acoustic and thermal <span class="hlt">waves</span> are investigated in media with a high radiative <span class="hlt">pressure</span>. The equations of hydrodynamics for matter and the radiative transfer equations in a moving medium in the Eddington approximation are used in the investigation. Model problems of <span class="hlt">waves</span> in a homogeneous medium with an abrupt jump in opacity and in a medium of variable opacity are presented. The characteristic and the times of variability are discussed. Amplitude for the brightness fluctuations for very massive stars are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24072460','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24072460"><span><span class="hlt">Pressures</span>, flow, and brain oxygenation during plateau <span class="hlt">waves</span> of intracranial <span class="hlt">pressure</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dias, Celeste; Maia, Isabel; Cerejo, António; Varsos, Georgios; Smielewski, Peter; Paiva, José-Artur; Czosnyka, Marek</p> <p>2014-08-01</p> <p>Plateau <span class="hlt">waves</span> are common in traumatic brain injury. They constitute abrupt increases of intracranial <span class="hlt">pressure</span> (ICP) above 40 mmHg associated with a decrease in cerebral perfusion <span class="hlt">pressure</span> (CPP). The aim of this study was to describe plateau <span class="hlt">waves</span> characteristics with multimodal brain monitoring in head injured patients admitted in neurocritical care. Prospective observational study in 18 multiple trauma patients with head injury admitted to Neurocritical Care Unit of Hospital Sao Joao in Porto. Multimodal systemic and brain monitoring of primary variables [heart rate, arterial blood <span class="hlt">pressure</span>, ICP, CPP, pulse amplitude, end tidal CO₂, brain temperature, brain tissue oxygenation <span class="hlt">pressure</span>, cerebral oximetry (CO) with transcutaneous near-infrared spectroscopy and cerebral blood flow (CBF)] and secondary variables related to cerebral compensatory reserve and cerebrovascular reactivity were supported by dedicated software ICM+ ( www.neurosurg.cam.ac.uk/icmplus) . The compiled data were analyzed in patients who developed plateau <span class="hlt">waves</span>. In this study we identified 59 plateau <span class="hlt">waves</span> that occurred in 44% of the patients (8/18). During plateau <span class="hlt">waves</span> CBF, cerebrovascular resistance, CO, and brain tissue oxygenation decreased. The duration and magnitude of plateau <span class="hlt">waves</span> were greater in patients with working cerebrovascular reactivity. After the end of plateau <span class="hlt">wave</span>, a hyperemic response was recorded in 64% of cases with increase in CBF and brain oxygenation. The magnitude of hyperemia was associated with better autoregulation status and low oxygenation levels at baseline. Multimodal brain monitoring facilitates identification and understanding of intrinsic vascular brain phenomenon, such as plateau <span class="hlt">waves</span>, and may help the adequate management of acute head injury at bed side.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27165902','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27165902"><span>Plateau <span class="hlt">Waves</span> of Intracranial <span class="hlt">Pressure</span> and Partial <span class="hlt">Pressure</span> of Cerebral Oxygen.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lang, Erhard W; Kasprowicz, Magdalena; Smielewski, Peter; Pickard, John; Czosnyka, Marek</p> <p>2016-01-01</p> <p>This study investigates 55 intracranial <span class="hlt">pressure</span> (ICP) plateau <span class="hlt">waves</span> recorded in 20 patients after severe traumatic brain injury (TBI) with a focus on a moving correlation coefficient between mean arterial <span class="hlt">pressure</span> (ABP) and ICP, called PRx, which serves as a marker of cerebrovascular reactivity, and a moving correlation coefficient between ABP and cerebral partial <span class="hlt">pressure</span> of oxygen (pbtO2), called ORx, which serves as a marker for cerebral oxygen reactivity. ICP and ICPamplitude increased significantly during the plateau <span class="hlt">waves</span>, whereas CPP and pbtO2 decreased significantly. ABP, ABP amplitude, and heart rate remained unchanged. In 73 % of plateau <span class="hlt">waves</span> PRx increased during the <span class="hlt">wave</span>. ORx showed an increase during and a decrease after the plateau <span class="hlt">waves</span>, which was not statistically significant. Our data show profound cerebral vasoparalysis on top of the <span class="hlt">wave</span> and, to a lesser extent, impairment of cerebral oxygen reactivity. The different behavior of the indices may be due to the different latencies of the cerebral blood flow and oxygen level control mechanisms. While cerebrovascular reactivity is a rapidly reacting mechanism, cerebral oxygen reactivity is slower.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/9550188','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/9550188"><span>In vivo <span class="hlt">pressure</span> measurements of lithotripsy shock <span class="hlt">waves</span> in pigs.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cleveland, R O; Lifshitz, D A; Connors, B A; Evan, A P; Willis, L R; Crum, L A</p> <p>1998-02-01</p> <p>Stone comminution and tissue damage in lithotripsy are sensitive to the acoustic field within the kidney, yet knowledge of shock <span class="hlt">waves</span> in vivo is limited. We have made measurements of lithotripsy shock <span class="hlt">waves</span> inside pigs with small hydrophones constructed of a 25-microm PVDF membrane stretched over a 21-mm diameter ring. A thin layer of silicone rubber was used to isolate the membrane electrically from pig fluid. A hydrophone was positioned around the pig kidney following a flank incision. Hydrophones were placed on either the anterior (shock <span class="hlt">wave</span> entrance) or the posterior (shock <span class="hlt">wave</span> exit) surface of the left kidney. Fluoroscopic imaging was used to orient the hydrophone perpendicular to the shock <span class="hlt">wave</span>. For each pig, the voltage settings (12-24 kV) and the position of the shock <span class="hlt">wave</span> focus within the kidney were varied. Waveforms measured within the pig had a shape very similar to those measured in water, but the peak <span class="hlt">pressure</span> was about 70% of that in water. The focal region in vivo was 82 mm x 20 mm, larger than that measured in vitro (57 mm x 12 mm). It appeared that a combination of nonlinear effects and inhomogeneities in the tissue broadened the focus of the lithotripter. The shock rise time was on the order of 100 ns, substantially more than the rise time measured in water, and was attributed to higher absorption in tissue.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930070363&hterms=Toluene&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DToluene','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930070363&hterms=Toluene&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DToluene"><span>An oxygen <span class="hlt">pressure</span> sensor using surface acoustic <span class="hlt">wave</span> devices</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leighty, Bradley D.; Upchurch, Billy T.; Oglesby, Donald M.</p> <p>1993-01-01</p> <p>Surface acoustic <span class="hlt">wave</span> (SAW) piezoelectric devices are finding widespread applications in many arenas, particularly in the area of chemical sensing. We have developed an oxygen <span class="hlt">pressure</span> sensor based on coating a SAW device with an oxygen binding agent which can be tailored to provide variable sensitivity. The coating is prepared by dissolving an oxygen binding agent in a toluene solution of a copolymer which is then sprayed onto the surface of the SAW device. Experimental data shows the feasibility of tailoring sensors to measure the partial <span class="hlt">pressure</span> of oxygen from 2.6 to 67 KPa (20 to 500 torr). Potential applications of this technology are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvD..92b3535F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvD..92b3535F"><span>Gravitational <span class="hlt">waves</span> <span class="hlt">induced</span> by spinor fields</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feng, Kaixi; Piao, Yun-Song</p> <p>2015-07-01</p> <p>In realistic model building, spinor fields with various masses are present. During inflation, a spinor field may <span class="hlt">induce</span> gravitational <span class="hlt">waves</span> as a second order effect. In this paper, we calculate the contribution of a single massive spinor field to the power spectrum of primordial gravitational <span class="hlt">wave</span> by using a retarded Green propagator. We find that the correction is scale invariant and of order H4/MP4 for arbitrary spinor mass mψ. Additionally, we also observe that when mψ≳H , the dependence of correction on mψ/H is nontrivial.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/427986','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/427986"><span>Free-surface <span class="hlt">wave-induced</span> separation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zhang, Z.J.; Stern, F.</p> <p>1996-09-01</p> <p>Free-surface <span class="hlt">wave-induced</span> separation is studied for a surface-piercing NACA 0024 foil over a range of Froude numbers (0, .2, .37, .55) through computational fluid dynamics of the unsteady Reynolds-averaged Navier-Stokes and the continuity equations with the Baldwin-Lomax turbulence model, exact nonlinear kinematic and approximate dynamic free-surface boundary conditions, and a body/free-surface conforming grid. The flow conditions and uncertainty analysis are discussed. A topological rule for a surface-piercing body is derived and verified. Steady-flow results are presented and analyzed with regard to the <span class="hlt">wave</span> and viscous flow and the nature of the separation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6321005','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6321005"><span>Time-resolved <span class="hlt">wave</span> profile measurements in copper to Megabar <span class="hlt">pressures</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chhabildas, L C; Asay, J R</p> <p>1981-01-01</p> <p>Many time-resolved techniques have been developed which have greatly aided in the understanding of dynamic material behavior such as the high <span class="hlt">pressure</span>-dynamic strength of materials. In the paper, time-resolved measurements of copper (at shock-<span class="hlt">induced</span> high <span class="hlt">pressures</span> and temperatures) are used to illustrate the capability of using such techniques to investigate high <span class="hlt">pressure</span> strength. Continuous shock loading and release <span class="hlt">wave</span> profiles have been made in copper to 93 GPa using velocity interferometric techniques. Fine structure in the release <span class="hlt">wave</span> profiles from the shocked state indicates an increase in shear strength of copper to 1.5 GPa at 93 GPa from its ambient value of 0.08 GPa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950007192','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950007192"><span><span class="hlt">Pressure</span> measurements of a three <span class="hlt">wave</span> journal air bearing</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dimofte, Florin; Addy, Harold E., Jr.</p> <p>1994-01-01</p> <p>In order to validate theoretical predictions of a <span class="hlt">wave</span> journal bearing concept, a bench test rig was assembled at NASA Lewis Research Center to measure the steady-state performance of a journal air bearing. The tester can run up to 30,000 RPM and the spindle has a run out of less than 1 micron. A three <span class="hlt">wave</span> journal bearing (50 mm diameter and 58 mm length) has been machined at NASA Lewis. The <span class="hlt">pressures</span> at 16 ports along the bearing circumference at the middle of the bearing length were measured and compared to the theoretical prediction. The bearing ran at speeds up to 15,000 RPM and certain loads. Good agreement was found between the measured and calculated <span class="hlt">pressures</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990AIPC..208..185I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990AIPC..208..185I"><span>Renal tissue damage <span class="hlt">induced</span> by focused shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ioritani, N.; Kuwahara, M.; Kambe, K.; Taguchi, K.; Saitoh, T.; Shirai, S.; Orikasa, S.; Takayama, K.; Lush, P. A.</p> <p>1990-07-01</p> <p>Biological evidence of renal arterial wall damage <span class="hlt">induced</span> by the microjet due to shock <span class="hlt">wave</span>-cavitation bubble interaction was demonstrated in living dog kidneys. We also intended to clarify the mechanism of renal tissue damage and the effects of different conditions of shock <span class="hlt">wave</span> exposure (peak <span class="hlt">pressure</span> of focused area, number of shots, exposure rate) on the renal tissue damage in comparison to stone disintegration. Disruption of arterial wall was the most remarkable histological change in the focused area of the kidneys. This lesion appeared as if the wall had been punctured by a needle. Large hematoma formation in the renal parenchym, and interstitial hemorrhage seemed to be the results of the arterial lesion. This arterial disorder also led to ischemic necrosis of the tubules surrounding the hematoma. Micro-angiographic examination of extracted kidneys also proved such arterial puncture lesions and ischemic lesions. The number of shots required for model stone disintegration was not inversely proportional to peak <span class="hlt">pressure</span>. It decreased markedly when peak <span class="hlt">pressure</span> was above 700 bar. Similarly thenumber of shots for hematoma formation was not inversely proportional to peak <span class="hlt">pressure</span>, however, this decreased markedly above 500 bar. These results suggested that a hematoma could be formed under a lower peak <span class="hlt">pressure</span> than that required for stone disintegration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6641429','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6641429"><span>Air <span class="hlt">pressure</span> <span class="hlt">waves</span> from Mount St. Helens eruptions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Reed, J.W.</p> <p>1980-01-01</p> <p>Barograms from a number of National Weather Service stations were assembled for the May 18, 1980, eruption and compared to airblast <span class="hlt">wave</span> propagations from large explosions. <span class="hlt">Wave</span> amplitudes at 50 to 300 km distances were about what might be expected from a nuclear explosion of between 1 megaton and 10 megaton yield. <span class="hlt">Pressure</span>-time signatures could not be resolved for the first compression phase, because of the slow paper recording speed. The 900 s negative phase duration was much too long for comparison with the negative phase of an explosion. Nevertheless, positive and negative amplitudes were about equal, as often observed at long distances from explosions. Calculations have been made for a simple finite amplitude propagation model. These show rough bounds on the source compression rate, to give the observed inaudible <span class="hlt">waves</span> at least to 54 km distance, yet cause audibly rapid compression at Seattle, near 150 km, and beyond.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160011537','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160011537"><span><span class="hlt">Pressure</span> Fluctuations <span class="hlt">Induced</span> by a Hypersonic Turbulent Boundary Layer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Duan, Lian; Choudhari, Meelan M.; Zhang, Chao</p> <p>2016-01-01</p> <p>Direct numerical simulations (DNS) are used to examine the <span class="hlt">pressure</span> fluctuations generated by a spatially-developed Mach 5.86 turbulent boundary layer. The unsteady <span class="hlt">pressure</span> field is analyzed at multiple wall-normal locations, including those at the wall, within the boundary layer (including inner layer, the log layer, and the outer layer), and in the free stream. The statistical and structural variations of <span class="hlt">pressure</span> fluctuations as a function of wall-normal distance are highlighted. Computational predictions for mean velocity pro les and surface <span class="hlt">pressure</span> spectrum are in good agreement with experimental measurements, providing a first ever comparison of this type at hypersonic Mach numbers. The simulation shows that the dominant frequency of boundary-layer-<span class="hlt">induced</span> <span class="hlt">pressure</span> fluctuations shifts to lower frequencies as the location of interest moves away from the wall. The <span class="hlt">pressure</span> <span class="hlt">wave</span> propagates with a speed nearly equal to the local mean velocity within the boundary layer (except in the immediate vicinity of the wall) while the propagation speed deviates from the Taylor's hypothesis in the free stream. Compared with the surface <span class="hlt">pressure</span> fluctuations, which are primarily vortical, the acoustic <span class="hlt">pressure</span> fluctuations in the free stream exhibit a significantly lower dominant frequency, a greater spatial extent, and a smaller bulk propagation speed. The freestream <span class="hlt">pressure</span> structures are found to have similar Lagrangian time and spatial scales as the acoustic sources near the wall. As the Mach number increases, the freestream acoustic fluctuations exhibit increased radiation intensity, enhanced energy content at high frequencies, shallower orientation of <span class="hlt">wave</span> fronts with respect to the flow direction, and larger propagation velocity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040182404','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040182404"><span>Numerical Investigations of High <span class="hlt">Pressure</span> Acoustic <span class="hlt">Waves</span> in Resonators</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Athavale, Mahesh; Pindera, Maciej; Daniels, Christopher C.; Steinetz, Bruce M.</p> <p>2004-01-01</p> <p>This presentation presents work on numerical investigations of nonlinear acoustic phenomena in resonators that can generate high-<span class="hlt">pressure</span> <span class="hlt">waves</span> using acoustic forcing of the flow. Time-accurate simulations of the flow in a closed cone resonator were performed at different oscillation frequencies and amplitudes, and the numerical results for the resonance frequency and fluid <span class="hlt">pressure</span> increase match the GRC experimental data well. Work on cone resonator assembly simulations has started and will involve calculations of the flow through the resonator assembly with and without acoustic excitation. A new technique for direct calculation of resonance frequency of complex shaped resonators is also being investigated. Script-driven command procedures will also be developed for optimization of the resonator shape for maximum <span class="hlt">pressure</span> increase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23716581','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23716581"><span>Exercise central (aortic) blood <span class="hlt">pressure</span> is predominantly driven by forward traveling <span class="hlt">waves</span>, not <span class="hlt">wave</span> reflection.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schultz, Martin G; Davies, Justin E; Roberts-Thomson, Phillip; Black, J Andrew; Hughes, Alun D; Sharman, James E</p> <p>2013-07-01</p> <p>Exercise hypertension independently predicts cardiovascular mortality, although little is known about exercise central hemodynamics. This study aimed to determine the contribution of arterial <span class="hlt">wave</span> travel and aortic reservoir characteristics to central blood <span class="hlt">pressure</span> (BP) during exercise. We hypothesized that exercise central BP would be principally related to forward <span class="hlt">wave</span> travel and aortic reservoir function. After routine diagnostic coronary angiography, invasive <span class="hlt">pressure</span> and flow velocity were recorded in the ascending aorta via sensor-tipped intra-arterial wires in 10 participants (age, 55±10 years; 70% men) free of coronary artery disease with normal left ventricular function. Measures were recorded at baseline and during supine cycle ergometry. Using <span class="hlt">wave</span> intensity analysis, dominant <span class="hlt">wave</span> types throughout the cardiac cycle were identified (forward and backward, compression, and decompression), and aortic reservoir and excess <span class="hlt">pressure</span> were calculated. Central systolic BP increased significantly with exercise (Δ=19±12 mm Hg; P<0.001). This was associated with increases in systolic forward compression <span class="hlt">waves</span> (Δ=12×10(6)±17×10(6) W·m(-2)·s(-1); P=0.045) and forward decompression <span class="hlt">waves</span> in late systole (Δ=9×10(6)±6×10(6) W·m(-2)·s(-1); P<0.001). Despite significant augmentation in BP (Δ=9±6 mm Hg; P=0.002), reflected <span class="hlt">waves</span> did not increase in magnitude (Δ=-1×10(6)±3×10(6) W·m(-2)·s(-1); P=0.2). Excess <span class="hlt">pressure</span> rose significantly with exercise (Δ=16±9 mm Hg; P<0.001), and reservoir <span class="hlt">pressure</span> integral fell (Δ=-5×10(5)±5×10(5) Pa·s; P=0.010). Change in reflection coefficient negatively correlated with change in central systolic BP (r=-0.68; P=0.03). We conclude that elevation of exercise central BP is principally because of increases in aortic forward traveling <span class="hlt">waves</span> generated by left ventricular ejection. These findings have relevance to understanding central BP waveform morphology and pathophysiology of exercise hypertension.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3433001','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3433001"><span>Narrowed Aortoseptal Angle Is Related to Increased Central Blood <span class="hlt">Pressure</span> and Aortic <span class="hlt">Pressure</span> <span class="hlt">Wave</span> Reflection</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Olafiranye, Oladipupo; Ibrahim, Mediha; Kamran, Haroon; Venner-Jones, Kinda; McFarlane, Samy I.; Salciccioli, Louis; Lazar, Jason M.</p> <p>2012-01-01</p> <p>The left ventricular (LV) aortoseptal angle (ASA) decreases with age, and is associated with basal septal hypertrophy (septal bulge). Enhanced arterial <span class="hlt">pressure</span> <span class="hlt">wave</span> reflection is known to impact LV hypertrophy. We assessed whether ASA is related to central blood <span class="hlt">pressure</span> (BP) and augmentation index (AI), a measure of the reflected <span class="hlt">pressure</span> <span class="hlt">wave</span>. We studied 75 subjects (age 62 ± 16 years; 66% female) who were referred for transthoracic echocardiography and had radial artery applanation tonometry within 24 h. Peripheral systolic BP (P-SBP), peripheral diastolic BP (P-DBP), and peripheral pulse <span class="hlt">pressure</span> (P-PP) were obtained by sphygmomanometry. Central BPs (C-SBP, C-DBP, C-PP) and AI were derived from applanation tonometry. AI was corrected for heart rate (AI75). The basal septal wall thickness (SWT), mid SWT and ASA were measured using the parasternal long axis echocardiographic view. Mean ASA and AI75 were 117 ± 11° and 22 ± 11%, respectively. ASA correlated with AI75 (r = −0.31, p ≤ 0.01), C-SBP (r = −0.24, p = 0.04), C-PP (r = −0.29, p = 0.01), but only showed a trend towards significance with P-SBP (r = −0.2, p = 0.09) and P-PP (r = −0.21, p = 0.08). Interestingly, C-PP was correlated with basal SWT (r = 0.27, p = 0.02) but not with mid SWT (r = 0.19, p = 0.11). On multivariate linear regression analysis, adjusted for age, gender, weight, and mean arterial <span class="hlt">pressure</span>, AI75 was an independent predictor of ASA (p = 0.02). Our results suggest that a narrowed ASA is related to increased <span class="hlt">pressure</span> <span class="hlt">wave</span> reflection and higher central BP. Further studies are needed to determine whether narrowed LV ASA is a cause or consequence of enhanced <span class="hlt">wave</span> reflection and whether other factors are involved. PMID:22969773</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRA..122.1658S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRA..122.1658S"><span>Dayside magnetospheric ULF <span class="hlt">wave</span> frequency modulated by a solar wind dynamic <span class="hlt">pressure</span> negative impulse</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shen, X. C.; Shi, Q. Q.; Zong, Q.-G.; Tian, A. M.; Nowada, M.; Sun, W. J.; Zhao, H. Y.; Hudson, M. K.; Wang, H. Z.; Fu, S. Y.; Pu, Z. Y.</p> <p>2017-02-01</p> <p>Ultralow frequency (ULF) <span class="hlt">waves</span> play an important role in the transport of the solar wind energy to the magnetosphere. In this paper, we present a ULF <span class="hlt">wave</span> event in the dayside magnetosphere which shows a sudden decrease in frequency from 3.1 to 2.3 mHz around 0756 UT on 11 January 2010, when a solar wind dynamic <span class="hlt">pressure</span> drop (from ˜5 to ˜2 nPa) was observed simultaneously. The <span class="hlt">wave</span> exits globally. The phase differences between electric and magnetic fields indicate that the compressional mode <span class="hlt">wave</span> is standing before and after the <span class="hlt">wave</span> frequency decrease. This result suggests that the ULF <span class="hlt">wave</span> should be associated with a cavity mode and the frequency decrease might be <span class="hlt">induced</span> by the change of the cavity size. A theoretical calculation was made to estimate the cavity mode frequency. The calculated <span class="hlt">wave</span> frequency before/after the negative impulse is 3.8/2.6 mHz, which is consistent with the observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6576447','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6576447"><span><span class="hlt">Pressure</span> <span class="hlt">wave</span> generated by the Mount St. Helens eruption</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Banister, J.B.</p> <p>1984-06-20</p> <p>Histories of the air <span class="hlt">pressure</span> <span class="hlt">wave</span> radiated from the eruption of Mount St. Helens on May 18, 1980, were calculated for two models of the eruption cloud expansion. The first considered the <span class="hlt">wave</span> radiated from an accelerated plane surface, while the second examined the <span class="hlt">wave</span> radiated from an expanding hemisphere. Two histories of eruption cloud motion based on photographs were used. Peak positive overpressures were about the same for these cloud motion histories of expansion into a hemisphere was assumed. If an accelerated planar source model was used, the peak positive <span class="hlt">pressures</span> have again about the same value in east and west direction, but values are about half in the north and south direction. Observed peak overpressures at microbarograph stations are somewhat higher than the calculated with the most marked departures at the greater surface ranges. These observed overpressures may have been about half the correct values, however. Microbarograph records show a weaker rarefaction than calculated histories or none at all. This can be explained, in part, by a lack of a real motion coherence in the slowing eruption cloud. If it is also possible the net ash cloud volume increased considerably after its vertical growth ceased and weakened the negative phase as well as lengthening the positive phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21697894','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21697894"><span>Impact of passive vibration on <span class="hlt">pressure</span> pulse <span class="hlt">wave</span> characteristics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sanchez-Gonzalez, M A; Wong, A; Vicil, F; Gil, R; Park, S Y; Figueroa, A</p> <p>2012-10-01</p> <p>The augmentation index (AIx), a marker of <span class="hlt">wave</span> reflection, decreases following acute leg exercise. Passive vibration (PV) causes local vasodilation that may reduce AIx. This study investigated the effects of acute PV on <span class="hlt">wave</span> reflection and aortic hemodynamics. In a crossover fashion 20 (M=9, F=11) healthy young (22±3 year) participants were randomized to 10 min PV or no vibration control (CON) trials. Subjects rested in the supine position with their legs over a vibration platform for the entire session. Radial waveforms were obtained by applanation tonometry before and after 3 min (Post-3) and 30 min (Post-30) of PV (∼5.37 G) or CON. No change in parameters was found at Post-3. We found significant time-by-trial interactions (P<0.01) at Post-30 for augmented <span class="hlt">pressure</span>, AIx and second systolic peak <span class="hlt">pressure</span> (P2), such that these parameters significantly (P<0.05) decreased (-2.3±3.0 mm Hg, -7.2±6.9% and -1.5±3.5 mm Hg, respectively) after PV but not after CON. These findings suggest that acute PV applied to the legs decreases AIx owing to a decrease in <span class="hlt">wave</span> reflection magnitude (P2). Further research is warranted to evaluate the potential clinical application of PV in populations at an increased cardiovascular risk who are unable to perform conventional exercise.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/983087','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/983087"><span>Measurement of sound speed vs. depth in South Pole ice: <span class="hlt">pressure</span> <span class="hlt">waves</span> and shear <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>IceCube Collaboration; Klein, Spencer</p> <p>2009-06-04</p> <p>We have measured the speed of both <span class="hlt">pressure</span> <span class="hlt">waves</span> and shear <span class="hlt">waves</span> as a function of depth between 80 and 500 m depth in South Pole ice with better than 1% precision. The measurements were made using the South Pole Acoustic Test Setup (SPATS), an array of transmitters and sensors deployed in the ice at the South Pole in order to measure the acoustic properties relevant to acoustic detection of astrophysical neutrinos. The transmitters and sensors use piezoceramics operating at {approx}5-25 kHz. Between 200 m and 500 m depth, the measured profile is consistent with zero variation of the sound speed with depth, resulting in zero refraction, for both <span class="hlt">pressure</span> and shear <span class="hlt">waves</span>. We also performed a complementary study featuring an explosive signal propagating vertically from 50 to 2250 m depth, from which we determined a value for the <span class="hlt">pressure</span> <span class="hlt">wave</span> speed consistent with that determined for shallower depths, higher frequencies, and horizontal propagation with the SPATS sensors. The sound speed profile presented here can be used to achieve good acoustic source position and emission time reconstruction in general, and neutrino direction and energy reconstruction in particular. The reconstructed quantities could also help separate neutrino signals from background.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA190668','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA190668"><span>An Analytical Model of <span class="hlt">Wave-Induced</span> Longshore Current Based on Power Law <span class="hlt">Wave</span> Height Decay.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1988-01-01</p> <p>34I ANALYtTICAL MODEL OF NAVE-<span class="hlt">INDUCED</span> LON6SHORE CURRENT BASED ON PONE* LAW.. (U) COASTAL ENG INEERING RESEAKNH CENTER VICKSBURG NS J N SMITH ET AL...j . - .L .V . : ; * AN ANALYTICAL MODEL OF <span class="hlt">WAVE-INDUCED</span> ~ z * LONGSHORE CURRENT BASED ON POWER LAW * - <span class="hlt">WAVE</span> HEIGHT DECAY by Jane McKee...I_ I IF 31592 11. TITLE (Include Security Classfication) • An Analytical Model of <span class="hlt">Wave-Induced</span> Longshore Current Based on Power Law . <span class="hlt">Wave</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850060847&hterms=temper&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dtemper','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850060847&hterms=temper&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dtemper"><span>Nonlinear shock acceleration. III - Finite <span class="hlt">wave</span> velocity, <span class="hlt">wave</span> <span class="hlt">pressure</span>, and entropy generation via <span class="hlt">wave</span> damping</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Eichler, D.</p> <p>1985-01-01</p> <p>The nonlinear theory of shock acceleration developed in earlier papers, which treated the <span class="hlt">waves</span> as being completely frozen into the fluid, is generalized to include <span class="hlt">wave</span> dynamics. In the limit where damping keeps the <span class="hlt">wave</span> amplitude small, it is found that a finite phase velocity (V sub ph) of the scattering <span class="hlt">waves</span> through the background fluid, tempers the acceleration generated by high Mach number shocks. Asymptotic spectra proportional to 1/E sq are possible only when the ratio of <span class="hlt">wave</span> velocity to shock velocity is less than 0.13. For a given asymptotic spectrum, the efficiency of relativistic particle production is found to be practically independent of the value of V sub ph, so that earlier results concerning its value remain valid for finite V sub ph. In the limit where there is no <span class="hlt">wave</span> damping, it is shown that for modest Alfven Mach numbers, approximately greater than 4 and less than 6, the magnetic field is amplified by the energetic particles to the point of being in rough equipartition with them, as models of synchrotron emission frequently take the field to be. In this case, the disordering and amplification of field energy may play a major role in the shock transition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18162539','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18162539"><span><span class="hlt">Pressure-induced</span> metallization of silane.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Xiao-Jia; Struzhkin, Viktor V; Song, Yang; Goncharov, Alexander F; Ahart, Muhtar; Liu, Zhenxian; Mao, Ho-Kwang; Hemley, Russell J</p> <p>2008-01-08</p> <p>There is a great interest in electronic transitions in hydrogen-rich materials under extreme conditions. It has been recently suggested that the group IVa hydrides such as methane (CH(4)), silane (SiH(4)), and germane (GeH(4)) become metallic at far lower <span class="hlt">pressures</span> than pure hydrogen at equivalent densities because the hydrogen is chemically compressed in group IVa hydride compounds. Here we report measurements of Raman and infrared spectra of silane under <span class="hlt">pressure</span>. We find that SiH(4) undergoes three phase transitions before becoming opaque at 27-30 GPa. The vibrational spectra indicate the material transforms to a polymeric (framework) structure in this higher <span class="hlt">pressure</span> range. Room-temperature infrared reflectivity data reveal that the material exhibits Drude-like metallic behavior above 60 GPa, indicating the onset of <span class="hlt">pressure-induced</span> metallization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2224186','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2224186"><span><span class="hlt">Pressure-induced</span> metallization of silane</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chen, Xiao-Jia; Struzhkin, Viktor V.; Song, Yang; Goncharov, Alexander F.; Ahart, Muhtar; Liu, Zhenxian; Mao, Ho-kwang; Hemley, Russell J.</p> <p>2008-01-01</p> <p>There is a great interest in electronic transitions in hydrogen-rich materials under extreme conditions. It has been recently suggested that the group IVa hydrides such as methane (CH4), silane (SiH4), and germane (GeH4) become metallic at far lower <span class="hlt">pressures</span> than pure hydrogen at equivalent densities because the hydrogen is chemically compressed in group IVa hydride compounds. Here we report measurements of Raman and infrared spectra of silane under <span class="hlt">pressure</span>. We find that SiH4 undergoes three phase transitions before becoming opaque at 27–30 GPa. The vibrational spectra indicate the material transforms to a polymeric (framework) structure in this higher <span class="hlt">pressure</span> range. Room-temperature infrared reflectivity data reveal that the material exhibits Drude-like metallic behavior above 60 GPa, indicating the onset of <span class="hlt">pressure-induced</span> metallization. PMID:18162539</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15089414','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15089414"><span>Shock <span class="hlt">pressures</span> <span class="hlt">induced</span> in condensed matter by laser ablation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Swift, Damian C; Tierney, Thomas E; Kopp, Roger A; Gammel, J Tinka</p> <p>2004-03-01</p> <p>The Trident laser was used to <span class="hlt">induce</span> shock <span class="hlt">waves</span> in samples of solid elements, with atomic numbers ranging from Be to Au, using pulses of 527 nm light around 1 ns long with irradiances of the order of 0.1 to 10 PW/m(2). States <span class="hlt">induced</span> by the resulting ablation process were investigated using laser Doppler velocimetry to measure the velocity history of the opposite surface. By varying the energy in the laser pulse, relations were inferred between the irradiance and the <span class="hlt">induced</span> <span class="hlt">pressure</span>. For samples in vacuo, an irradiance constant in time does not produce a constant <span class="hlt">pressure</span>. Radiation hydrodynamics simulations were used to investigate the relationship between the precise pulse shape and the <span class="hlt">pressure</span> history. In this regime of time and irradiance, it was possible to reproduce the experimental data to within their uncertainty by including conductivity-dependent deposition of laser energy, heat conduction, gray radiation diffusion, and three temperature hydrodynamics in the treatment of the plasma, with ionizations calculated using the Thomas-Fermi equation. States <span class="hlt">induced</span> in the solid sample were fairly insensitive to the details of modeling in the plasma, so Hugoniot points may be estimated from experiments of this type given a reasonable model of the plasma. More useful applications include the generation of dynamic loading to investigate compressive strength and phase transitions, and for sample recovery.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750008127','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750008127"><span>Application of monochromatic ocean <span class="hlt">wave</span> forecasts to prediction of <span class="hlt">wave-induced</span> currents</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Poole, L. R.</p> <p>1975-01-01</p> <p>The use of monochromatic wind-<span class="hlt">wave</span> forecasts in prediction of wind-<span class="hlt">wave-induced</span> currents was assessed. Currents were computed for selected combinations of wind conditions by using a spectrum approach which was developed by using the Bretschneider <span class="hlt">wave</span> spectrum for partially developed wind seas. These currents were compared with currents computed by using the significant and average monochromatic <span class="hlt">wave</span> parameters related to the Bretschneider spectrum. Results indicate that forecasts of significant <span class="hlt">wave</span> parameters can be used to predict surface wind-<span class="hlt">wave-induced</span> currents. Conversion of these parameters to average <span class="hlt">wave</span> parameters can furnish reasonable estimates of subsurface current values.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28528253','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28528253"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> transformations in sorbic acid.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Saraiva, G D; Maia, J R; Lima, J A; Nogueira, C E S; Freire, P T C; de Sousa, F F; Teixeira, A M R; Mendes Filho, J</p> <p>2017-09-05</p> <p>This research reports a <span class="hlt">pressure</span> dependent Raman study of the sorbic acid between 0.0 and 10.0GPa. The unpolarized Raman spectra were measured in the spectral range of 20-3000cm(-1). The high-<span class="hlt">pressure</span> Raman scattering study of the sorbic acid showed that it underwent a gradual, disordering process. At the room temperature and at the ambient <span class="hlt">pressure</span> conditions, the crystal structure of the sorbic acid belongs to the monoclinic system with a C2/c (C2h(6)) space group. The <span class="hlt">pressure</span> increase <span class="hlt">induced</span> a higher disorder in the monoclinic unit cell, since a single bending mode, and only very broad stretching Raman modes are present at <span class="hlt">pressure</span> of ~10GPa. Upon <span class="hlt">pressure</span> release the high-<span class="hlt">pressure</span> phase transforms directly into the ambient-<span class="hlt">pressure</span> phase. The presence of the internal vibrational modes is a guarantee that the molecular structure is maintained. Beyond this, the presence of external modes shows that the crystal has a memory to reverse the process and suggest that the crystal, which was in high disorder (broad Raman bands), does not suffer decomposition in the crystalline structure. The DFT calculations for the sorbic acid were performed in order to understand the vibrational properties. The theoretical study showed that the volume of the unit cell and beta angle decrease significatively when passing from the 0.0GPa to 8.0GPa. The decreases in the volume and beta angle of this particular unit cell were supposed to <span class="hlt">induce</span> the larger increase in the bandwidths of the observed bands, pointing to some disorder in the monoclinic phase. Copyright © 2017 Elsevier B.V. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AcSpA.184..327S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AcSpA.184..327S"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> transformations in sorbic acid</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saraiva, G. D.; Maia, J. R.; Lima, J. A.; Nogueira, C. E. S.; Freire, P. T. C.; de Sousa, F. F.; Teixeira, A. M. R.; Mendes Filho, J.</p> <p>2017-09-01</p> <p>This research reports a <span class="hlt">pressure</span> dependent Raman study of the sorbic acid between 0.0 and 10.0 GPa. The unpolarized Raman spectra were measured in the spectral range of 20-3000 cm- 1. The high-<span class="hlt">pressure</span> Raman scattering study of the sorbic acid showed that it underwent a gradual, disordering process. At the room temperature and at the ambient <span class="hlt">pressure</span> conditions, the crystal structure of the sorbic acid belongs to the monoclinic system with a C2/c (C2h6) space group. The <span class="hlt">pressure</span> increase <span class="hlt">induced</span> a higher disorder in the monoclinic unit cell, since a single bending mode, and only very broad stretching Raman modes are present at <span class="hlt">pressure</span> of 10 GPa. Upon <span class="hlt">pressure</span> release the high-<span class="hlt">pressure</span> phase transforms directly into the ambient-<span class="hlt">pressure</span> phase. The presence of the internal vibrational modes is a guarantee that the molecular structure is maintained. Beyond this, the presence of external modes shows that the crystal has a memory to reverse the process and suggest that the crystal, which was in high disorder (broad Raman bands), does not suffer decomposition in the crystalline structure. The DFT calculations for the sorbic acid were performed in order to understand the vibrational properties. The theoretical study showed that the volume of the unit cell and beta angle decrease significatively when passing from the 0.0 GPa to 8.0 GPa. The decreases in the volume and beta angle of this particular unit cell were supposed to <span class="hlt">induce</span> the larger increase in the bandwidths of the observed bands, pointing to some disorder in the monoclinic phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15904355','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15904355"><span>Brane-<span class="hlt">induced</span>-gravity shock <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kaloper, Nemanja</p> <p>2005-05-13</p> <p>We construct exact gravitational field solutions for a relativistic particle localized on a tensional brane in brane-<span class="hlt">induced</span> gravity. They are a generalization of gravitational shock <span class="hlt">waves</span> in 4D de Sitter space. We provide the metrics for both the normal branch and the self-inflating branch Dvali-Gabadadze-Porrati brane worlds, and compare them to the 4D Einstein gravity solution and to the case when gravity resides only in the 5D bulk, without any brane-localized curvature terms. At short distances the <span class="hlt">wave</span> profile looks the same as in four dimensions. The corrections appear only far from the source, where they differ from the long distance corrections in 4D de Sitter space. We also discover a new nonperturbative channel for energy emission into the bulk from the self-inflating [corrected] branch, when gravity is modified at the de Sitter radius.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4728694','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4728694"><span>Microcantilever Actuation by Laser <span class="hlt">Induced</span> Photoacoustic <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gao, Naikun; Zhao, Dongfang; Jia, Ran; Liu, Duo</p> <p>2016-01-01</p> <p>We present here a combined theoretical and experimental investigation on effective excitation of microcantilever by using photoacoustic <span class="hlt">waves</span>. The photoacoustic <span class="hlt">waves</span> arose from a vibrating Al foil <span class="hlt">induced</span> by an intensity-modulated laser. We demonstrate that, superior to photothermal excitation, this new configuration avoids direct heating of the microcantilever, thus minimizing undesired thermal effects on the vibration of microcantilever, while still keeps the advantage of being a remote, non-contact excitation method. We also measured the vibration amplitude of the microcantilever as a function of distance between the microcantilever and the Al foil and found that the amplitudes decay gradually according to the inverse distance law. This method is universal and can be adopted in bio-microelectromechanical systems (BioMEMs) for the detection of small signals where detrimental thermal effects must be avoided. PMID:26814360</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...619935G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...619935G"><span>Microcantilever Actuation by Laser <span class="hlt">Induced</span> Photoacoustic <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gao, Naikun; Zhao, Dongfang; Jia, Ran; Liu, Duo</p> <p>2016-01-01</p> <p>We present here a combined theoretical and experimental investigation on effective excitation of microcantilever by using photoacoustic <span class="hlt">waves</span>. The photoacoustic <span class="hlt">waves</span> arose from a vibrating Al foil <span class="hlt">induced</span> by an intensity-modulated laser. We demonstrate that, superior to photothermal excitation, this new configuration avoids direct heating of the microcantilever, thus minimizing undesired thermal effects on the vibration of microcantilever, while still keeps the advantage of being a remote, non-contact excitation method. We also measured the vibration amplitude of the microcantilever as a function of distance between the microcantilever and the Al foil and found that the amplitudes decay gradually according to the inverse distance law. This method is universal and can be adopted in bio-microelectromechanical systems (BioMEMs) for the detection of small signals where detrimental thermal effects must be avoided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhTea..54..118M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhTea..54..118M"><span>Tunnel <span class="hlt">pressure</span> <span class="hlt">waves</span> - A smartphone inquiry on rail travel</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Müller, Andreas; Hirth, Michael; Kuhn, Jochen</p> <p>2016-02-01</p> <p>When traveling by rail, you might have experienced the following phenomenon: The train enters a tunnel, and after some seconds a noticeable <span class="hlt">pressure</span> change occurs, as perceived by your ears or even by a rapid wobbling of the train windows. The basic physics is that <span class="hlt">pressure</span> <span class="hlt">waves</span> created by the train travel down the tunnel, are reflected at its other end, and travel back until they meet the train again. Here we will show (i) how this effect can be well understood as a kind of large-scale outdoor case of a textbook paradigm, and (ii) how, e.g., a prediction of the tunnel length from the inside of a moving train on the basis of this model can be validated by means of a mobile phone measurement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010APS..MAR.Q8005B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010APS..MAR.Q8005B"><span>Current-<span class="hlt">induced</span> spin <span class="hlt">wave</span> Doppler shift</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bailleul, Matthieu</p> <p>2010-03-01</p> <p>In metal ferromagnets -namely Fe, Co and Ni and their alloys- magnetism and electrical transport are strongly entangled (itinerant magnetism). This results in a number of properties such as the tunnel and giant magnetoresistance (i.e. the dependence of the electrical resistance on the magnetic state) and the more recently addressed spin transfer (i.e. the ability to manipulate the magnetic state with the help of an electrical current). The spin <span class="hlt">waves</span>, being the low-energy elementary excitations of any ferromagnet, also exist in itinerant magnets, but they are expected to exhibit some peculiar properties due the itinerant character of the carriers. Accessing these specific properties experimentally could shed a new light on the microscopic mechanism governing itinerant magnetism, which -in turn- could help in optimizing material properties for spintronics applications. As a simple example of these specific properties, it was predicted theoretically that forcing a DC current through a ferromagnetic metal should <span class="hlt">induce</span> a shift of the frequency of the spin <span class="hlt">waves</span> [1,2]. This shift can be identified to a Doppler shift undergone by the electron system when it is put in motion by the electrical current. We will show how detailed spin <span class="hlt">wave</span> measurements allow one to access this current-<span class="hlt">induced</span> Doppler shift [3]. From an experimental point of view, we will discuss the peculiarities of propagating spin <span class="hlt">wave</span> spectroscopy experiments carried out at a sub-micrometer length-scale and with MHz frequency resolution. Then, we will discuss the measured value of the Doppler shift in the context of both the old two-current model of spin-polarized transport and the more recent model of adiabatic spin transfer torque. [4pt] [1] P.Lederer and D.L. Mills, Phys.Rev. 148, 542 (1966).[0pt] [2] J. Fernandez-Rossier et al., Phys. Rev. B 69, 174412 (2004)[0pt] [3] V. Vlaminck and M. Bailleul, Science 322, 410 (2008).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1821h0001Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1821h0001Z"><span>Simulations of nonlinear continuous <span class="hlt">wave</span> <span class="hlt">pressure</span> fields in FOCUS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Xiaofeng; Hamilton, Mark F.; McGough, Robert J.</p> <p>2017-03-01</p> <p>The Khokhlov - Zabolotskaya - Kuznetsov (KZK) equation is a parabolic approximation to the Westervelt equation that models the effects of diffraction, attenuation, and nonlinearity. Although the KZK equation is only valid in the far field of the paraxial region for mildly focused or unfocused transducers, the KZK equation is widely applied in medical ultrasound simulations. For a continuous <span class="hlt">wave</span> input, the KZK equation is effectively modeled by the Bergen Code [J. Berntsen, Numerical Calculations of Finite Amplitude Sound Beams, in M. F. Hamilton and D. T. Blackstock, editors, Frontiers of Nonlinear Acoustics: Proceedings of 12th ISNA, Elsevier, 1990], which is a finite difference model that utilizes operator splitting. Similar C++ routines have been developed for FOCUS, the `Fast Object-Oriented C++ Ultrasound Simulator' (http://www.egr.msu.edu/˜fultras-web) to calculate nonlinear <span class="hlt">pressure</span> fields generated by axisymmetric flat circular and spherically focused ultrasound transducers. This new routine complements an existing FOCUS program that models nonlinear ultrasound propagation with the angular spectrum approach [P. T. Christopher and K. J. Parker, J. Acoust. Soc. Am. 90, 488-499 (1991)]. Results obtained from these two nonlinear ultrasound simulation approaches are evaluated and compared for continuous <span class="hlt">wave</span> linear simulations. The simulation results match closely in the farfield of the paraxial region, but the results differ in the nearfield. The nonlinear <span class="hlt">pressure</span> field generated by a spherically focused transducer with a peak surface <span class="hlt">pressure</span> of 0.2MPa radiating in a lossy medium with β = 3.5 is simulated, and the computation times are also evaluated. The nonlinear simulation results demonstrate acceptable agreement in the focal zone. These two related nonlinear simulation approaches are now included with FOCUS to enable convenient simulations of nonlinear <span class="hlt">pressure</span> fields on desktop and laptop computers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S53D..05M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S53D..05M"><span>On the Generation of Multiple Atmospheric <span class="hlt">Pressure</span> <span class="hlt">Waves</span> Observed During Violent Volcanic Eruptions.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Medici, E. F.; Waite, G. P.</p> <p>2015-12-01</p> <p>One or more atmospheric <span class="hlt">pressure</span> <span class="hlt">waves</span> followed by a supersonic jet may be generated during the over <span class="hlt">pressurized</span> vapor-solid-liquid mixture ejection of a violent volcanic eruption. The source of these multiple atmospheric <span class="hlt">pressure</span> <span class="hlt">waves</span> could have different origins. Among the physical mechanisms that could explain these behaviors are pulsating eruptions, the dynamics of shock <span class="hlt">waves</span>, coupled <span class="hlt">pressure</span> <span class="hlt">wave</span>-supersonic jet interaction, or a combination of all these factors. In order to elucidate the causes of these complex fluid flow dynamics, a series of analog volcanic eruption experiments using an atmospheric shock tube were performed. During the testing, single and multiple <span class="hlt">pressure</span> <span class="hlt">waves</span> and the subsequent supersonic jet were generated. The controlled laboratory conditions enable studies of the most relevant variables potentially responsible for the formation of the multiple <span class="hlt">pressure</span> <span class="hlt">waves</span>. The tests were performed using dry, compressed nitrogen at standard room temperature that was free of particles. Yet, under this idealization of a real volcanic eruption, multiple <span class="hlt">pressure</span> <span class="hlt">waves</span> were observed on the high-speed video imaging and recorded on the <span class="hlt">pressure</span> transducer. The amount of energy being released on each test was varied to achieve different discharge dynamics and the formation of single and multiple <span class="hlt">pressure</span> <span class="hlt">waves</span>. The preliminary experimental observations indicate a coupled <span class="hlt">pressure</span> <span class="hlt">wave</span>-jet interaction as source of multiple <span class="hlt">pressure</span> <span class="hlt">waves</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/102219','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/102219"><span><span class="hlt">Pressure-induced</span> transformations in molecular crystals</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Taylor, R.D.; Hearne, G.R. |; Pasternak, M.P.</p> <p>1995-09-01</p> <p>A review is given on the unique features of the Moessbauer spectroscopy (MS) which by virtue of the quadrupole interaction and the lattice dynamics allows one to characterize some structural properties in the <span class="hlt">pressure-induced</span> amorphous state of molecular crystals. Experiments were performed in GeI{sub 4}, SnI{sub 4} and SnBr{sub 4} by means of {sup 119}Sn and {sup 129}I MS with <span class="hlt">pressures</span> to 35 GPa at cryogenic temperatures using diamond anvil cells.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFMOS52E..04H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFMOS52E..04H"><span><span class="hlt">Wave</span> Acceleration <span class="hlt">Induced</span> Sediment Transport in the Surf Zone</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hoefel, F.; Elgar, S.</p> <p>2002-12-01</p> <p>A bedload sediment transport formulation (Drake and Calantoni, 2001) that accounts for the effects of near-bottom <span class="hlt">wave</span>-orbital velocity acceleration skewness predicts onshore sandbar migration observed near Duck, NC. Including acceleration effects in an energetics sediment transport model results in improved skill in reproducing cross-shore sandbar migration patterns observed over a 40 day period during which the bar moved both offshore in storms and onshore between storms. These results suggest that skewed acceleration time series, associated with the pitched forward shapes of nearly breaking and broken <span class="hlt">waves</span>, play an important role in <span class="hlt">wave-induced</span> sediment transport in the surf zone. The passage of steep <span class="hlt">wave</span> fronts results in spikes in acceleration when orbital velocities are directed onshore, producing strong horizontal <span class="hlt">pressure</span> gradient forces that act on the sediment. In contrast to velocity skewness, which remains approximately constant across the surf zone, acceleration skewness is observed to increase from small values offshore to a maximum near the bar crest, and then to decrease toward the shoreline, producing cross-shore spatial gradients in acceleration-driven transport that are consistent with erosion offshore and accretion onshore of the bar crest. As the sandbar migrates shoreward, the maximum of acceleration skewness also moves onshore, causing a positive feedback mechanism that promotes continued onshore sediment transport motion provided the forcing remains constant. Funded by ARO, ONR, and NOPP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25015922','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25015922"><span>Genesis of the characteristic pulmonary venous <span class="hlt">pressure</span> waveform as described by the reservoir-<span class="hlt">wave</span> model.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bouwmeester, J Christopher; Belenkie, Israel; Shrive, Nigel G; Tyberg, John V</p> <p>2014-09-01</p> <p>Conventional haemodynamic analysis of pulmonary venous and left atrial (LA) <span class="hlt">pressure</span> waveforms yields substantial forward and backward <span class="hlt">waves</span> throughout the cardiac cycle; the reservoir <span class="hlt">wave</span> model provides an alternative analysis with minimal <span class="hlt">waves</span> during diastole. <span class="hlt">Pressure</span> and flow in a single pulmonary vein (PV) and the main pulmonary artery (PA) were measured in anaesthetized dogs and the effects of hypoxia and nitric oxide, volume loading, and positive-end expiratory <span class="hlt">pressure</span> (PEEP) were observed. The reservoir <span class="hlt">wave</span> model was used to determine the reservoir contribution to PV <span class="hlt">pressure</span> and flow. Subtracting reservoir <span class="hlt">pressure</span> and flow resulted in 'excess' quantities which were treated as <span class="hlt">wave-related.Wave</span> intensity analysis of excess <span class="hlt">pressure</span> and flow quantified the contributions of <span class="hlt">waves</span> originating upstream (from the PA) and downstream (from the LA and/or left ventricle (LV)).Major features of the characteristic PV waveform are caused by sequential LA and LV contraction and relaxation creating backward compression (i.e.<span class="hlt">pressure</span>-increasing) <span class="hlt">waves</span> followed by decompression (i.e. <span class="hlt">pressure</span>-decreasing) <span class="hlt">waves</span>. Mitral valve opening is linked to a backwards decompression <span class="hlt">wave</span> (i.e. diastolic suction). During late systole and early diastole, forward <span class="hlt">waves</span> originating in the PA are significant. These <span class="hlt">waves</span> were attenuated less with volume loading and delayed with PEEP. The reservoir <span class="hlt">wave</span> model shows that the forward and backward <span class="hlt">waves</span> are negligible during LV diastasis and that the changes in <span class="hlt">pressure</span> and flow can be accounted for by the discharge of upstream reservoirs. In sharp contrast, conventional analysis posits forward and backward <span class="hlt">waves</span> such that much of the energy of the forward <span class="hlt">wave</span> is opposed by the backward <span class="hlt">wave</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4192704','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4192704"><span>Genesis of the characteristic pulmonary venous <span class="hlt">pressure</span> waveform as described by the reservoir-<span class="hlt">wave</span> model</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bouwmeester, J Christopher; Belenkie, Israel; Shrive, Nigel G; Tyberg, John V</p> <p>2014-01-01</p> <p>Conventional haemodynamic analysis of pulmonary venous and left atrial (LA) <span class="hlt">pressure</span> waveforms yields substantial forward and backward <span class="hlt">waves</span> throughout the cardiac cycle; the reservoir <span class="hlt">wave</span> model provides an alternative analysis with minimal <span class="hlt">waves</span> during diastole. <span class="hlt">Pressure</span> and flow in a single pulmonary vein (PV) and the main pulmonary artery (PA) were measured in anaesthetized dogs and the effects of hypoxia and nitric oxide, volume loading, and positive-end expiratory <span class="hlt">pressure</span> (PEEP) were observed. The reservoir <span class="hlt">wave</span> model was used to determine the reservoir contribution to PV <span class="hlt">pressure</span> and flow. Subtracting reservoir <span class="hlt">pressure</span> and flow resulted in ‘excess’ quantities which were treated as <span class="hlt">wave</span>-related. <span class="hlt">Wave</span> intensity analysis of excess <span class="hlt">pressure</span> and flow quantified the contributions of <span class="hlt">waves</span> originating upstream (from the PA) and downstream (from the LA and/or left ventricle (LV)). Major features of the characteristic PV waveform are caused by sequential LA and LV contraction and relaxation creating backward compression (i.e. <span class="hlt">pressure</span>-increasing) <span class="hlt">waves</span> followed by decompression (i.e. <span class="hlt">pressure</span>-decreasing) <span class="hlt">waves</span>. Mitral valve opening is linked to a backwards decompression <span class="hlt">wave</span> (i.e. diastolic suction). During late systole and early diastole, forward <span class="hlt">waves</span> originating in the PA are significant. These <span class="hlt">waves</span> were attenuated less with volume loading and delayed with PEEP. The reservoir <span class="hlt">wave</span> model shows that the forward and backward <span class="hlt">waves</span> are negligible during LV diastasis and that the changes in <span class="hlt">pressure</span> and flow can be accounted for by the discharge of upstream reservoirs. In sharp contrast, conventional analysis posits forward and backward <span class="hlt">waves</span> such that much of the energy of the forward <span class="hlt">wave</span> is opposed by the backward <span class="hlt">wave</span>. PMID:25015922</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26ES...82a2012K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26ES...82a2012K"><span><span class="hlt">Wave-induced</span> current at Anmok Beach, Korea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, H.; Park, D.; Lee, S.; Lim, H.-S.</p> <p>2017-08-01</p> <p>Currents were measured at two stations on Anmok Beach, and were reproduced by a numerical model system CST3D-WA. Anmok area is known as <span class="hlt">wave</span>-dominated coast, and the mean tidal range small. Field data with strong <span class="hlt">wave-induced</span> current are rare, especially at shallow water depth. Measured currents were strong during three periods. The largest instantaneous current speed at a station during a period was 46 cm/s. CST3D-WA system simulated <span class="hlt">wave-induced</span> current for the three periods, and compared with measurements. The deviation of the incident peak <span class="hlt">wave</span> direction from the normal direction to the shoreline strongly affects the <span class="hlt">wave-induced</span> current speed and direction. When the deviation angle crosses the normal direction, the <span class="hlt">wave-induced</span> alongshore current direction changes between SE and NW. CST3D-WA is thought to have successfully reproduced the <span class="hlt">wave-induced</span> current fields on this beach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApPhL.110v1902Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApPhL.110v1902Z"><span><span class="hlt">Pressure-induced</span> elastic anomaly in a polyamorphous metallic glass</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zeng, Qiaoshi; Zeng, Zhidan; Lou, Hongbo; Kono, Yoshio; Zhang, Bo; Kenney-Benson, Curtis; Park, Changyong; Mao, Wendy L.</p> <p>2017-05-01</p> <p>The <span class="hlt">pressure-induced</span> transitions discovered in metallic glasses (MGs) have attracted considerable research interest offering an exciting opportunity to study polyamorphism in densely packed systems. Despite the large body of work on these systems, the elastic properties of the MGs during polyamorphic transitions remain unclear. Here, using an in situ high-<span class="hlt">pressure</span> ultrasonic sound velocity technique integrated with x-ray radiography and x-ray diffraction in a Paris-Edinburgh cell, we accurately determined both the compressional and shear <span class="hlt">wave</span> velocities of a polyamorphous Ce68Al10Cu20Co2 MG up to 5.8 GPa. We observed elastic anomalies of a MG with minima (at ˜1.5 GPa) in the sound velocities, bulk modulus, and Poisson's ratio during its polyamorphic transition. This behavior was discussed in comparison to the elastic anomalies of silica glass and crystalline Ce.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1915734M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1915734M"><span>Investigation of the spatial variability and possible origins of wind-<span class="hlt">induced</span> air <span class="hlt">pressure</span> fluctuations responsible for <span class="hlt">pressure</span> pumping</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mohr, Manuel; Laemmel, Thomas; Maier, Martin; Zeeman, Matthias; Longdoz, Bernard; Schindler, Dirk</p> <p>2017-04-01</p> <p>The exchange of greenhouse gases between the soil and the atmosphere is highly relevant for the climate of the Earth. Recent research suggests that wind-<span class="hlt">induced</span> air <span class="hlt">pressure</span> fluctuations can alter the soil gas transport and therefore soil gas efflux significantly. Using a newly developed method, we measured soil gas transport in situ in a well aerated forest soil. Results from these measurements showed that the commonly used soil gas diffusion coefficient is enhanced up to 30% during periods of strong wind-<span class="hlt">induced</span> air <span class="hlt">pressure</span> fluctuations. The air <span class="hlt">pressure</span> fluctuations above the forest floor are only <span class="hlt">induced</span> at high above-canopy wind speeds (> 5 m s-1) and lie in the frequency range 0.01-0.1 Hz. Moreover, the amplitudes of air <span class="hlt">pressure</span> fluctuations in this frequency range show a clear quadratic dependence on mean above-canopy wind speed. However, the origin of these wind-<span class="hlt">induced</span> <span class="hlt">pressure</span> fluctuations is still unclear. Airflow measurements and high-precision air <span class="hlt">pressure</span> measurements were conducted at three different vegetation-covered sites (conifer forest, deciduous forest, grassland) to investigate the spatial variability of dominant air <span class="hlt">pressure</span> fluctuations, their origin and vegetation-dependent characteristics. At the conifer forest site, a vertical profile of air <span class="hlt">pressure</span> fluctuations was measured and an array consisting of five <span class="hlt">pressure</span> sensors were installed at the forest floor. At the grassland site, the air <span class="hlt">pressure</span> measurements were compared with wind observations made by ground-based LIDAR and spatial temperature observations from a fibre-optic sensing network (ScaleX Campaign 2016). Preliminary results show that at all sites the amplitudes of relevant air <span class="hlt">pressure</span> fluctuations increase with increasing wind speed. Data from the array measurements reveal that there are no time lags between the air <span class="hlt">pressure</span> signals of different heights, but a time lag existed between the air <span class="hlt">pressure</span> signals of the sensors distributed laterally on the forest floor</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1913128L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1913128L"><span>Bedforms <span class="hlt">induced</span> by solitary <span class="hlt">waves</span>: laboratory studies on generation and migration rate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>la Forgia, Giovanni; Adduce, Claudia; Falcini, Federico; Paola, Chris</p> <p>2017-04-01</p> <p>This study presents experiments on the formation of sandy bedforms, produced by surface solitary <span class="hlt">waves</span> (SSWs) in shallow water conditions. The experiments were carried out in a 12.0 m long, 0.15 m wide and 0.5 m high flume, at Saint Anthony Falls Laboratory in Minneapolis. The tank is filled by fresh water and a removable gate, placed at the left hand-side of the tank, divides the flume in two regions: the lock region and the ambient fluid region. The standard lock-release method generates SSWs by producing a displacement between the free surfaces that are divided by the gate. <span class="hlt">Wave</span> amplitude, wavelength, and celerity depend on the lock length and on the water level difference between the two regions. Natural sand particles (D50=0.64) are arranged on the bottom in order to form a horizontal flat layer with a thickness of 2 cm. A digital <span class="hlt">pressure</span> gauge and a high-resolution acoustic velocimeter allowed us to measure, locally, both <span class="hlt">pressure</span> and 3D water velocity <span class="hlt">induced</span> on the bottom by each <span class="hlt">wave</span>. Image analysis technique is then used to obtain the main <span class="hlt">wave</span> features: amplitude, wavelength, and celerity. Dye is finally used as vertical tracer to mark the horizontal speed <span class="hlt">induced</span> by the <span class="hlt">wave</span>. For each experiment we generated 400 <span class="hlt">waves</span>, having the same features and we analyzed their action on sand particles placed on the bottom. The stroke, <span class="hlt">induced</span> by each <span class="hlt">wave</span>, entails a shear stress on the sand particles, causing sediment transport in the direction of <span class="hlt">wave</span> propagation. Immediately after the <span class="hlt">wave</span> passage, a back flow occurs near the bottom. The horizontal <span class="hlt">pressure</span> gradient and the velocity field <span class="hlt">induced</span> by the <span class="hlt">wave</span> cause the boundary layer separation and the consequent reverse flow. Depending on the <span class="hlt">wave</span> features and on the water depth, the boundary shear stress <span class="hlt">induced</span> by the reverse flow can exceed the critical value <span class="hlt">inducing</span> the back motion of the sand particles. The experiments show that the particle back motion is localized at particular cross sections along the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..SHK.E1003G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..SHK.E1003G"><span>Estimating explosive performance from laser-<span class="hlt">induced</span> shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gottfried, Jennifer</p> <p>2015-06-01</p> <p>A laboratory-scale method for predicting explosive performance (e.g., detonation velocity and <span class="hlt">pressure</span>) based on milligram quantities of material is currently being developed. This technique is based on schlieren imaging of the shock <span class="hlt">wave</span> generated in air by the formation of a laser-<span class="hlt">induced</span> plasma on the surface of an energetic material. A large suite of pure and composite conventional energetic materials has been tested. Based on the observed linear correlation between the laser-<span class="hlt">induced</span> shock velocity and the measured performance from full-scale detonation testing, this method is a potential screening tool for the development of new energetic materials and formulations prior to detonation testing. Recent results on the extension of this method to metal-containing energetic materials will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005PhRvB..71b0404V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005PhRvB..71b0404V"><span>Field-<span class="hlt">induced</span> spin-density <span class="hlt">wave</span> in (TMTSF)2NO3</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vignolles, David; Audouard, Alain; Nardone, Marc; Brossard, Luc; Bouguessa, Sabrina; Fabre, Jean-Marc</p> <p>2005-01-01</p> <p>Interlayer magnetoresistance of the Bechgaard salt (TMTSF)2NO3 is investigated up to 50 T under <span class="hlt">pressures</span> of a few kilobars. This compound, the Fermi surface of which is quasi-two-dimensional at low temperature, is a semimetal under <span class="hlt">pressure</span>. Nevertheless, a field-<span class="hlt">induced</span> spin-density <span class="hlt">wave</span> is evidenced at 8.5 kbars above ˜20T . This state is characterized by a drastically different spectrum of the quantum oscillations compared to the low-<span class="hlt">pressure</span> spin-density <span class="hlt">wave</span> state.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JTePh..62..523S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JTePh..62..523S"><span>Influence of the initial <span class="hlt">pressure</span> of polydisperse bubble media on characteristics of detonation <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sychev, A. I.</p> <p>2017-04-01</p> <p>The influence of the initial <span class="hlt">pressure</span> of polydisperse bubble media on the initiation conditions, structure, propagation velocity, and the <span class="hlt">pressure</span> of detonation <span class="hlt">waves</span> has been experimentally studied. It has been established that variations in the initial <span class="hlt">pressure</span> of the bubble medium is an effective method of controlling the parameters of bubble detonation <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26142299','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26142299"><span>Further insights into blood <span class="hlt">pressure</span> <span class="hlt">induced</span> premature beats: Transient depolarizations are associated with fast myocardial deformation upon <span class="hlt">pressure</span> decline.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Haemers, Peter; Sutherland, George; Cikes, Maja; Jakus, Nina; Holemans, Patricia; Sipido, Karin R; Willems, Rik; Claus, Piet</p> <p>2015-11-01</p> <p>An acute increase in blood <span class="hlt">pressure</span> is associated with the occurrence of premature ventricular complexes (PVCs). We aimed to study the timing of these PVCs with respect to afterload-<span class="hlt">induced</span> changes in myocardial deformation in a controlled, preclinically relevant, novel closed-chest pig model. An acute left ventricular (LV) afterload challenge was <span class="hlt">induced</span> by partial balloon inflation in the descending aorta, lasting 5-10 heartbeats (8 pigs; 396 inflations). Balloon inflation enhanced the reflected <span class="hlt">wave</span> (augmentation index 30% ± 8% vs 59% ± 6%; P < .001), increasing systolic central blood <span class="hlt">pressure</span> by 35% ± 4%. This challenge resulted in a more abrupt LV <span class="hlt">pressure</span> decline, which was delayed beyond ventricular repolarization (rate of <span class="hlt">pressure</span> decline 0.16 ± 0.01 mm Hg/s vs 0.27 ± 0.04 mm Hg/ms; P < .001 and interval T-<span class="hlt">wave</span> to peak <span class="hlt">pressure</span> 1 ± 12 ms vs 36 ± 9 ms; P = .008), during which the velocity of myocardial shortening at the basal septum increased abruptly (ie, postsystolic shortening) (peak strain rate -0.6 ± 0.5 s(-1) vs -2.5 ± 0.8 s(-1); P < .001). It is exactly at this time of LV <span class="hlt">pressure</span> decline, with increased postsystolic shortening, and not at peak <span class="hlt">pressure</span>, that PVCs occur (22% of inflations). These PVCs preferentially occurred at the basal and apical segments. In the same regions, monophasic action potentials demonstrated the appearance of delayed afterdepolarization-like transient depolarizations as origin of PVCs. An acute blood <span class="hlt">pressure</span> increase results in a more abrupt LV <span class="hlt">pressure</span> decline, which is delayed after ventricular repolarization. This has a profound effect on myocardial mechanics with enhanced postsystolic shortening. Coincidence with <span class="hlt">induced</span> transient depolarizations and PVCs provides support for the mechanoelectrical origin of <span class="hlt">pressure-induced</span> premature beats. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS21B1711K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS21B1711K"><span>Optical Estimation of Depth <span class="hlt">Induced</span> <span class="hlt">Wave</span> Breaking Distributions over Complex Bathymetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Keen, A. S.; Holman, R. A.</p> <p>2012-12-01</p> <p>Parametric depth-<span class="hlt">induced</span>-breaking dissipation models have shown great skill at predicting time averaged <span class="hlt">wave</span> heights across the surf zone. First proposed by Battjes & Janssen (1978), these models balance the incoming <span class="hlt">wave</span> energy flux with a roller dissipation term. This roller dissipation term is estimated by calculating the dissipation for one characteristic broken <span class="hlt">wave</span> and then multiplying this quantity by the fraction of broken <span class="hlt">waves</span>. To describe the fraction of broken <span class="hlt">waves</span>, a typical assumption asserts that <span class="hlt">wave</span> heights are nearly Rayleigh distributed [Thornton & Guza (1983)] allowing a sea state to be described by only a few parameters. While many experiments have validated the cross shore <span class="hlt">wave</span> height profiles, few field experiments have been performed to analyze the probability distribution of breaking <span class="hlt">wave</span> heights over a barred beach profile. The goal of the present research is to determine the distribution of broken and unbroken <span class="hlt">wave</span> heights across a natural barred beach profile. Field data collected during the Surf Zone Optics experiment (a Multi-disciplinary University Research Initiative) in Duck, North Carolina, consisted of an array of in-situ <span class="hlt">pressure</span> sensors and optical remote sensing cameras. Sea surface elevation time series from the in-situ <span class="hlt">pressure</span> sensors are used here to resolve <span class="hlt">wave</span> height distributions at multiple locations across the surf zone. Breaking <span class="hlt">wave</span> height distributions are resolved based upon a combination of the <span class="hlt">pressure</span> sensor and optically based breaker detection algorithm. Since breaking is easily able to be tracked by video imaging, breaking <span class="hlt">waves</span> are flagged in the sea surface elevation series and binned into a broken <span class="hlt">wave</span> height distribution. Results of this analysis are compared with model predictions based upon the Battjes & Janssen (1978), Thornton & Guza (1983) and Janssen & Battjes (2007) models to assess the validity of each <span class="hlt">wave</span> height distribution model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730045264&hterms=canine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcanine','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730045264&hterms=canine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcanine"><span>Influence of flow and <span class="hlt">pressure</span> on <span class="hlt">wave</span> propagation in the canine aorta.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Histand, M. B.; Anliker, M.</p> <p>1973-01-01</p> <p>Data on <span class="hlt">wave</span> speed acquired from 20 anesthetized dogs showed that the thoracic aorta was essentially nondispersive for small artificially generated <span class="hlt">pressure</span> <span class="hlt">waves</span> traveling in the downstream or the upstream direction and having frequencies between 40 and 120 Hz. The amplitude of these <span class="hlt">waves</span> decayed exponentially with the distance traveled. Theoretical studies are cited which have shown that changes in <span class="hlt">wave</span> speed due to variations in <span class="hlt">pressure</span> and flow produce marked nonlinear effects in hemodynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21743529','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21743529"><span>Effect of focusing conditions on laser-<span class="hlt">induced</span> shock <span class="hlt">waves</span> at titanium-water interface.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nath, Arpita; Khare, Alika</p> <p>2011-07-01</p> <p>The spatial and temporal evolution of laser-<span class="hlt">induced</span> shock <span class="hlt">waves</span> at a titanium-water interface was analyzed using a beam deflection setup. The focusing conditions of the source laser were varied, and its effect onto the dynamics of shock <span class="hlt">waves</span> was elucidated. For a tightly focused condition, the speed of the shock <span class="hlt">wave</span> was ~6.4 Km/s, whereas for a defocused condition the velocities reduced to <3 km/s at the vicinity of the titanium-water interface. When the laser is focused a few millimeters above the target, i.e., within the water, the emission of dual shock <span class="hlt">waves</span> was observed toward the rear side of the focal volume. These shock <span class="hlt">waves</span> originate from the titanium-water interface as well as from the pure water breakdown region, respectively. The shock <span class="hlt">wave</span> <span class="hlt">pressure</span> is estimated from the shock <span class="hlt">wave</span> velocity using the Newton's second law across a shock <span class="hlt">wave</span> discontinuity. The shock <span class="hlt">wave</span> <span class="hlt">pressure</span> for a tightly focused condition was 18 GPa, whereas under a defocused condition the <span class="hlt">pressure</span> experienced was ≤1 GPa in the proximity of target.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22036636','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22036636"><span>Effect of focusing conditions on laser-<span class="hlt">induced</span> shock <span class="hlt">waves</span> at titanium-water interface</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Nath, Arpita; Khare, Alika</p> <p>2011-07-01</p> <p>The spatial and temporal evolution of laser-<span class="hlt">induced</span> shock <span class="hlt">waves</span> at a titanium-water interface was analyzed using a beam deflection setup. The focusing conditions of the source laser were varied, and its effect onto the dynamics of shock <span class="hlt">waves</span> was elucidated. For a tightly focused condition, the speed of the shock <span class="hlt">wave</span> was {approx}6.4 Km/s, whereas for a defocused condition the velocities reduced to <3 km/s at the vicinity of the titanium-water interface. When the laser is focused a few millimeters above the target, i.e., within the water, the emission of dual shock <span class="hlt">waves</span> was observed toward the rear side of the focal volume. These shock <span class="hlt">waves</span> originate from the titanium-water interface as well as from the pure water breakdown region, respectively. The shock <span class="hlt">wave</span> <span class="hlt">pressure</span> is estimated from the shock <span class="hlt">wave</span> velocity using the Newton's second law across a shock <span class="hlt">wave</span> discontinuity. The shock <span class="hlt">wave</span> <span class="hlt">pressure</span> for a tightly focused condition was 18 GPa, whereas under a defocused condition the <span class="hlt">pressure</span> experienced was {<=}1 GPa in the proximity of target.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhD...49V5401S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhD...49V5401S"><span>Intraluminal bubble dynamics <span class="hlt">induced</span> by lithotripsy shock <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, Jie; Bai, Jiaming; Zhou, Yufeng</p> <p>2016-12-01</p> <p>Extracorporeal shock <span class="hlt">wave</span> lithotripsy (ESWL) has been the first option in the treatment of calculi in the upper urinary tract since its introduction. ESWL-<span class="hlt">induced</span> renal injury is also found after treatment and is assumed to associate with intraluminal bubble dynamics. To further understand the interaction of bubble expansion and collapse with the vessel wall, the finite element method (FEM) was used to simulate intraluminal bubble dynamics and calculate the distribution of stress in the vessel wall and surrounding soft tissue during cavitation. The effects of peak <span class="hlt">pressure</span>, vessel size, and stiffness of soft tissue were investigated. Significant dilation on the vessel wall occurs after contacting with rapid and large bubble expansion, and then vessel deformation propagates in the axial direction. During bubble collapse, large shear stress is found to be applied to the vessel wall at a clinical lithotripter setting (i.e. 40 MPa peak <span class="hlt">pressure</span>), which may be the mechanism of ESWL-<span class="hlt">induced</span> vessel rupture. The decrease of vessel size and viscosity of soft tissue would enhance vessel deformation and, consequently, increase the generated shear stress and normal stresses. Meanwhile, a significantly asymmetric bubble boundary is also found due to faster axial bubble expansion and shrinkage than in radial direction, and deformation of the vessel wall may result in the formation of microjets in the axial direction. Therefore, this numerical work would illustrate the mechanism of ESWL-<span class="hlt">induced</span> tissue injury in order to develop appropriate counteractive strategies for reduced adverse effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994PhDT........90G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994PhDT........90G"><span>A Experimental Study of Fluctuating <span class="hlt">Pressure</span> Loads Beneath Swept Shock <span class="hlt">Wave</span>/boundary Layer Interactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Garg, Sanjay</p> <p></p> <p>An experimental research program providing basic knowledge and establishing a database on the fluctuating <span class="hlt">pressure</span> loads produced on aerodynamic surfaces beneath three-dimensional shock <span class="hlt">wave</span>/boundary layer interactions is described. Such loads constitute a fundamental problem of critical concern to future supersonic and hypersonic flight vehicles. A turbulent boundary layer on a flat plate is subjected to interactions with swept planar shock <span class="hlt">waves</span> generated by sharp fins. Fin angles from 10 ^circ to 20^circ at freestream Mach numbers of 3 and 4 produce a variety of interaction strengths from weak to very strong. Miniature <span class="hlt">pressure</span> transducers flush-mounted in the flat plate have been used to measure interaction-<span class="hlt">induced</span> wall <span class="hlt">pressure</span> fluctuations. The distributions of properties of the <span class="hlt">pressure</span> fluctuations, such as their rms level, amplitude distribution and power spectra, are also determined. Measurements have been made for the first time in the aft regions of these interactions, revealing fluctuating <span class="hlt">pressure</span> levels as high as 155 dB, which places them in the category of significant aeroacoustic load generators. The fluctuations near the foot of the fin are dominated by low frequency (0-5 kHz) components, and are caused by a previously unrecognized random motion of the primary attachment line. This phenomenon is probably intimately linked to the unsteadiness of the separation shock at the start of the interaction. The characteristics of the <span class="hlt">pressure</span> fluctuations are explained in light of the features of the interaction flowfield. In particular, physical mechanisms responsible for the generation of high levels of surface <span class="hlt">pressure</span> fluctuations are proposed based on the results of the study. The unsteadiness of the flowfield of the surface is also examined via a novel, non-intrusive optical technique. Results show that the entire shock structure generated by the interaction undergoes relatively low-frequency oscillations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.715a2003R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.715a2003R"><span>Mass Spectrometry of Atmospheric <span class="hlt">Pressure</span> Surface <span class="hlt">Wave</span> Discharges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ridenti, M. A.; Souza-Corrêa, J. A.; Amorim, J.</p> <p>2016-05-01</p> <p>By applying mass spectrometry techniques, we carried out measurements of ionic mass spectrum and their energy distribution in order to investigate an atmospheric argon discharge by using a surfatron surface-<span class="hlt">wave</span> device. The mass and energy distribution measurements were performed with fixed flow rate (2.5 SLM) of pure argon gas (99.999%) and different Ar-O2 gas mixture compositions (99-1, 98-2 and 97-3). The mass spectra and energy distributions were recorded for Ar+, O+, O+ 2, N+ and N2 +. The axial distribution profiles of ionic mass and their energy were obtained for different experimental conditions as a function of the plasma length. The results showed that the peak of the positive ion energy distributions shifted to higher energies and also that the distribution width increased as the distance between the sampling orifice and the launcher gap was increased. It was also found that under certain experimental conditions the ion flux of atomic species were higher than the ion flux of their diatomic counterpart. The motivation of this study was to obtain a better understanding of a surface <span class="hlt">wave</span> discharge in atmospheric <span class="hlt">pressure</span> that may play a key role on new second generation biofuel technologies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRC..122.2205R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRC..122.2205R"><span>Current-<span class="hlt">induced</span> dissipation in spectral <span class="hlt">wave</span> models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rapizo, H.; Babanin, A. V.; Provis, D.; Rogers, W. E.</p> <p>2017-03-01</p> <p>Despite many recent developments of the parameterization for <span class="hlt">wave</span> dissipation in spectral models, it is evident that when <span class="hlt">waves</span> propagate onto strong adverse currents the rate of energy dissipation is not properly estimated. The issue of current-<span class="hlt">induced</span> dissipation is studied through a comprehensive data set in the tidal inlet of Port Phillip Heads, Australia. The <span class="hlt">wave</span> parameters analyzed are significantly modulated by the tidal currents. <span class="hlt">Wave</span> height in conditions of opposing currents (ebb tide) can reach twice the offshore value, whereas during coflowing currents (flood), it can be reduced to half. The wind-<span class="hlt">wave</span> model SWAN is able to reproduce the tide-<span class="hlt">induced</span> modulation of <span class="hlt">waves</span> and the results show that the variation of currents is the dominant factor in modifying the <span class="hlt">wave</span> field. In stationary simulations, the model provides an accurate representation of <span class="hlt">wave</span> height for slack and flood tides. During ebb tides, <span class="hlt">wave</span> energy is highly overestimated over the opposing current jet. None of the four parameterizations for <span class="hlt">wave</span> dissipation tested performs satisfactorily. A modification to enhance dissipation as a function of the local currents is proposed. It consists of the addition of a factor that represents current-<span class="hlt">induced</span> <span class="hlt">wave</span> steepening and it is scaled by the ratio of spectral energy to the threshold breaking level. The new term asymptotes to the original form as the current in the <span class="hlt">wave</span> direction tends to zero. The proposed modification considerably improves <span class="hlt">wave</span> height and mean period in conditions of adverse currents, whereas the good model performance in coflowing currents is unaltered.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.S31B1059A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.S31B1059A"><span>Poroelastic <span class="hlt">Wave</span> Propagation With a 3D Velocity-Stress-<span class="hlt">Pressure</span> Finite-Difference Algorithm</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aldridge, D. F.; Symons, N. P.; Bartel, L. C.</p> <p>2004-12-01</p> <p>Seismic <span class="hlt">wave</span> propagation within a three-dimensional, heterogeneous, isotropic poroelastic medium is numerically simulated with an explicit, time-domain, finite-difference algorithm. A system of thirteen, coupled, first-order, partial differential equations is solved for the particle velocity vector components, the stress tensor components, and the <span class="hlt">pressure</span> associated with solid and fluid constituents of the two-phase continuum. These thirteen dependent variables are stored on staggered temporal and spatial grids, analogous to the scheme utilized for solution of the conventional velocity-stress system of isotropic elastodynamics. Centered finite-difference operators possess 2nd-order accuracy in time and 4th-order accuracy in space. Seismological utility is enhanced by an optional stress-free boundary condition applied on a horizontal plane representing the earth's surface. Absorbing boundary conditions are imposed on the flanks of the 3D spatial grid via a simple wavefield amplitude taper approach. A massively parallel computational implementation, utilizing the spatial domain decomposition strategy, allows investigation of large-scale earth models and/or broadband <span class="hlt">wave</span> propagation within reasonable execution times. Initial algorithm testing indicates that a point force density and/or moment density source activated within a poroelastic medium generates diverging fast and slow P <span class="hlt">waves</span> (and possibly an S-<span class="hlt">wave</span>)in accord with Biot theory. Solid and fluid particle velocities are in-phase for the fast P-<span class="hlt">wave</span>, whereas they are out-of-phase for the slow P-<span class="hlt">wave</span>. Conversions between all <span class="hlt">wave</span> types occur during reflection and transmission at interfaces. Thus, although the slow P-<span class="hlt">wave</span> is regarded as difficult to detect experimentally, its presence is strongly manifest within the complex of <span class="hlt">waves</span> generated at a lithologic or fluid boundary. Very fine spatial and temporal gridding are required for high-fidelity representation of the slow P-<span class="hlt">wave</span>, without <span class="hlt">inducing</span> excessive</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22492644','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22492644"><span>Cavitation inception by the backscattering of <span class="hlt">pressure</span> <span class="hlt">waves</span> from a bubble interface</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Takahira, Hiroyuki Ogasawara, Toshiyuki Mori, Naoto Tanaka, Moe</p> <p>2015-10-28</p> <p>The secondary cavitation that occurs by the backscattering of focused ultrasound from a primary cavitation bubble caused by the negative <span class="hlt">pressure</span> part of the ultrasound (Maxwell, et al., 2011) might be useful for the energy exchange due to bubble oscillations in High Intensity Focused Ultrasound (HIFU). The present study is concerned with the cavitation inception by the backscattering of ultrasound from a bubble. In the present experiment, a laser-<span class="hlt">induced</span> bubble which is generated by a pulsed focused laser beam with high intensity is utilized as a primary cavitation bubble. After generating the bubble, focused ultrasound is emitted to the bubble. The acoustic field and the bubble motion are observed with a high-speed video camera. It is confirmed that the secondary cavitation bubble clouds are generated by the backscattering from the laser-<span class="hlt">induced</span> bubble. The growth of cavitation bubble clouds is analyzed with the image processing method. The experimental results show that the height and width of the bubble clouds grow in stepwise during their evolution. The direct numerical simulations are also conducted for the backscattering of incident <span class="hlt">pressure</span> <span class="hlt">waves</span> from a bubble in order to evaluate a <span class="hlt">pressure</span> field near the bubble. It is shown that the ratio of a bubble collapse time t{sub 0} to a characteristic time of <span class="hlt">wave</span> propagation t{sub S}, η = t{sub 0}/t{sub s}, is an important determinant for generating negative <span class="hlt">pressure</span> region by backscattering. The minimum <span class="hlt">pressure</span> location by the backscattering in simulations is in good agreement with the experiment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28000131','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28000131"><span>Transcranial Doppler Monitoring of Intracranial <span class="hlt">Pressure</span> Plateau <span class="hlt">Waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cardim, Danilo; Schmidt, Bernhard; Robba, Chiara; Donnelly, Joseph; Puppo, Corina; Czosnyka, Marek; Smielewski, Peter</p> <p>2017-06-01</p> <p>Transcranial Doppler (TCD) has been used to estimate ICP noninvasively (nICP); however, its accuracy varies depending on different types of intracranial hypertension. Given the high specificity of TCD to detect cerebrovascular events, this study aimed to compare four TCD-based nICP methods during plateau <span class="hlt">waves</span> of ICP. A total of 36 plateau <span class="hlt">waves</span> were identified in 27 patients (traumatic brain injury) with TCD, ICP, and ABP simultaneous recordings. The nICP methods were based on: (1) interaction between flow velocity (FV) and ABP using a "black-box" mathematical model (nICP_BB); (2) diastolic FV (nICP_FV d ); (3) critical closing <span class="hlt">pressure</span> (nICP_CrCP), and (4) pulsatility index (nICP_PI). Analyses focused on relative changes in time domain between ICP and noninvasive estimators during plateau <span class="hlt">waves</span> and the magnitude of changes (∆ between baseline and plateau) in real ICP and its estimators. A ROC analysis for an ICP threshold of 35 mmHg was performed. In time domain, nICP_PI, nICP_BB, and nICP_CrCP presented similar correlations: 0.80 ± 0.24, 0.78 ± 0.15, and 0.78 ± 0.30, respectively. nICP_FV d presented a weaker correlation (R = 0.62 ± 0.46). Correlations between ∆ICP and ∆nICP were better represented by nICP_CrCP and BB, R = 0.48, 0.44 (p < 0.05), respectively. nICP_FV d and PI presented nonsignificant ∆ correlations. ROC analysis showed moderate to good areas under the curve for all methods: nICP_BB, 0.82; nICP_FV d , 0.77; nICP_CrCP, 0.79; and nICP_PI, 0.81. Changes of ICP in time domain during plateau <span class="hlt">waves</span> were replicated by nICP methods with strong correlations. In addition, the methods presented high performance for detection of intracranial hypertension. However, absolute accuracy for noninvasive ICP assessment using TCD is still low and requires further improvement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18829180','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18829180"><span>A thoracic mechanism of mild traumatic brain injury due to blast <span class="hlt">pressure</span> <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Courtney, A C; Courtney, M W</p> <p>2009-01-01</p> <p>The mechanisms by which blast <span class="hlt">pressure</span> <span class="hlt">waves</span> cause mild-to-moderate traumatic brain injury (mTBI) are an open question. Possibilities include acceleration of the head, direct passage of the blast <span class="hlt">wave</span> via the cranium, and propagation of the blast <span class="hlt">wave</span> to the brain via a thoracic mechanism. The hypothesis that the blast <span class="hlt">pressure</span> <span class="hlt">wave</span> reaches the brain via a thoracic mechanism is considered in light of ballistic and blast <span class="hlt">pressure</span> <span class="hlt">wave</span> research. Ballistic <span class="hlt">pressure</span> <span class="hlt">waves</span>, caused by penetrating ballistic projectiles or ballistic impacts to body armor, can only reach the brain via an internal mechanism and have been shown to cause cerebral effects. Similar effects have been documented when a blast <span class="hlt">pressure</span> <span class="hlt">wave</span> has been applied to the whole body or focused on the thorax in animal models. While vagotomy reduces apnea and bradycardia due to ballistic or blast <span class="hlt">pressure</span> <span class="hlt">waves</span>, it does not eliminate neural damage in the brain, suggesting that the <span class="hlt">pressure</span> <span class="hlt">wave</span> directly affects the brain cells via a thoracic mechanism. An experiment is proposed which isolates the thoracic mechanism from cranial mechanisms of mTBI due to blast <span class="hlt">wave</span> exposure. Results have implications for evaluating risk of mTBI due to blast exposure and for developing effective protection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27566141','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27566141"><span>Frequency and wavelength prediction of ultrasonic <span class="hlt">induced</span> liquid surface <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mahravan, Ehsan; Naderan, Hamid; Damangir, Ebrahim</p> <p>2016-12-01</p> <p>A theoretical investigation of parametric excitation of liquid free surface by a high frequency sound <span class="hlt">wave</span> is preformed, using potential flow theory. <span class="hlt">Pressure</span> and velocity distributions, resembling the sound <span class="hlt">wave</span>, are applied to the free surface of the liquid. It is found that for impinging <span class="hlt">wave</span> two distinct capillary frequencies will be excited: One of them is the same as the frequency of the sound <span class="hlt">wave</span>, and the other is equal to the natural frequency corresponding to a wavenumber equal to the horizontal wavenumber of the sound <span class="hlt">wave</span>. When the <span class="hlt">wave</span> propagates in vertical direction, mathematical formulation leads to an equation, which has resonance frequency equal to half of the excitation frequency. This can explain an important contradiction between the frequency and the wavelength of capillary <span class="hlt">waves</span> in the two cases of normal and inclined interaction of the sound <span class="hlt">wave</span> and the free surface of the liquid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSH21A2386T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSH21A2386T"><span>Non-gyrotropic <span class="hlt">pressure</span> anisotropy <span class="hlt">induced</span> by velocity shear.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tenerani, A.; Del Sarto, D.; Pegoraro, F.; Califano, F.</p> <p>2015-12-01</p> <p>We discuss how, in a collisionless magnetized plasma, a sheared velocity field may lead to the anisotropization of an initial Maxwellian state. By including the full <span class="hlt">pressure</span> tensor dynamics in a fluid plasma model, we show, analytically and numerically, that a sheared velocity field makes an initial isotropic state anisotropic and non-gyrotropic [1], i.e., makes the plasma <span class="hlt">pressure</span> tensor anisotropic also in the plane perpendicular to the magnetic field. The propagation of transverse magneto-elastic <span class="hlt">waves</span> in the anisotropic plasma affects the process of formation of a non-gyrotropic <span class="hlt">pressure</span> and can lead to its spatial filamentation. This plasma dynamics implies in particular that isotropic MHD equilibria cease to be equilibria in presence of a stationary sheared flow. Similarly, in the case of turbulence, where small-scale spatial inhomogeneities are naturally developed during the direct cascade, we may expect that isotropic turbulent states are not likely to exist whenever a full <span class="hlt">pressure</span> tensor evolution is accounted for. These results may be relevant to understanding the agyrotropic <span class="hlt">pressure</span> configurations which are well documented in solar wind measurements and possibly correlated to plasma flows (see e.g. Refs.[2,3]), and which have also been measured in Vlasov simulations of Alfvenic turbulence [4]. [1] D. Del Sarto, F. Pegoraro, F. Califano, "<span class="hlt">Pressure</span> anisotropy and small spatial scales <span class="hlt">induced</span> by a velocity shear", http://arxiv.org/abs/1507.04895 [2] H.F. Astudillo, E. Marsch, S. Livi, H. Rosenbauer, "TAUS measurements of non-gyrotropic distribution functions of solar wind alpha particles", AIP Conf. Proc. 328, 289 (1996). [3] A. Posner, M.W. Liemhon, T.H. Zurbuchen, "Upstream magnetospheric ion flux tube within a magnetic cloud: Wind/STICS", Geophys. Res. Lett. 30, (2003). [4] S. Servidio, F. Valentini, F. Califano, P. Veltri, "Local kinetic effects in Two-Dimensional Plasma Turbulence", Phys. Rev. Lett. 108, 045001 (2012).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFMMR53D..08D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFMMR53D..08D"><span>On the Concordance of Static High <span class="hlt">Pressure</span> Phase Transformation Data on Minerals With Shock <span class="hlt">Wave</span> Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Carli, P. S.; El Goresy, A.; Xie, Z.; Sharp, T. G.</p> <p>2006-12-01</p> <p>About 50 years ago, shock <span class="hlt">wave</span> researchers were confounded by the apparent rapidity of shock-<span class="hlt">induced</span> phase transformations and invoked special mechanisms as an explanation. Some workers speculatively interpret shock <span class="hlt">wave</span> data as indicative of very rapid reconstructive phase transformations of minerals at modest temperatures. The belief that kinetic effects are negligible has justified the use of microsecond duration shock recovery experiments to interpret much longer duration shock effects in terrestrial impact craters and in meteorites. Here we summarize the extensive evidence that phase transformations under shock compression are governed by the same kinetics as phase transitions under static compression. Hugoniot measurements on quartz and feldspars have been interpreted as indicating phase transitions to dense phases at <span class="hlt">pressures</span> near 35 GPa. Release adiabat measurements imply that these phases persist on release of <span class="hlt">pressure</span> down to about 7 GPa, below which there is expansion to a final density appropriate to a glass. Microsecond-duration shock recovery experiments support this interpretation; a low density amorphous phase (diaplectic glass) is recovered. A similar effect is observed in static compression experiments conducted at room temperature at a lower <span class="hlt">pressure</span>, 12-15 GPa. The <span class="hlt">pressure</span> difference is a kinetic effect; the transition requires higher shock <span class="hlt">pressures</span> (implying higher shock temperatures) to run to completion on a microsecond time scale. Direct evidence for kinetic effects on the tectosilicate transformation is found in studies of naturally shocked meteorites that contain melt veins. When the melt veins solidify under <span class="hlt">pressure</span>, the resultant mineralogy together with vein cooling calculations constrains the shock <span class="hlt">pressure</span>-time history. In some samples, in which the shock <span class="hlt">pressure</span> is constrained by vein mineralogy to a range of 17-25 Gpa, one may observe the presence of diaplectic glass in only near-vein regions heated by conduction from the vein</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3247849','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3247849"><span>Dysglycemia <span class="hlt">induces</span> abnormal circadian blood <span class="hlt">pressure</span> variability</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2011-01-01</p> <p>Background Prediabetes (PreDM) in asymptomatic adults is associated with abnormal circadian blood <span class="hlt">pressure</span> variability (abnormal CBPV). Hypothesis Systemic inflammation and glycemia influence circadian blood <span class="hlt">pressure</span> variability. Methods Dahl salt-sensitive (S) rats (n = 19) after weaning were fed either an American (AD) or a standard (SD) diet. The AD (high-glycemic-index, high-fat) simulated customary human diet, provided daily overabundant calories which over time lead to body weight gain. The SD (low-glycemic-index, low-fat) mirrored desirable balanced human diet for maintaining body weight. Body weight and serum concentrations for fasting glucose (FG), adipokines (leptin and adiponectin), and proinflammatory cytokines [monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α)] were measured. Rats were surgically implanted with C40 transmitters and blood <span class="hlt">pressure</span> (BP-both systolic; SBP and diastolic; DBP) and heart rate (HR) were recorded by telemetry every 5 minutes during both sleep (day) and active (night) periods. Pulse <span class="hlt">pressure</span> (PP) was calculated (PP = SBP-DBP). Results [mean(SEM)]: The AD fed group displayed significant increase in body weight (after 90 days; p < 0.01). Fasting glucose, adipokine (leptin and adiponectin) concentrations significantly increased (at 90 and 172 days; all p < 0.05), along with a trend for increased concentrations of systemic pro-inflammatory cytokines (MCP-1 and TNF-α) on day 90. The AD fed group, with significantly higher FG, also exhibited significantly elevated circadian (24-hour) overall mean SBP, DBP, PP and HR (all p < 0.05). Conclusion These data validate our stated hypothesis that systemic inflammation and glycemia influence circadian blood <span class="hlt">pressure</span> variability. This study, for the first time, demonstrates a cause and effect relationship between caloric excess, enhanced systemic inflammation, dysglycemia, loss of blood <span class="hlt">pressure</span> control and abnormal CBPV. Our results provide the fundamental</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JPhCS.656a2023K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JPhCS.656a2023K"><span>Study on <span class="hlt">Pressure</span> <span class="hlt">Wave</span> Propagation in a Liquid Containing Spherical Bubbles in a Rectangular Duct</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kawahara, Junya; Watanabe, Masao; Kobayashi, Kazumichi</p> <p>2015-12-01</p> <p><span class="hlt">Pressure</span> <span class="hlt">wave</span> propagation in a liquid containing several bubbles is numerically investigated. We simulate liner plane <span class="hlt">wave</span> propagation in a liquid containing 10 spherical bubbles in a rectangular duct with the equation of motion for N spherical bubbles. The sound <span class="hlt">pressures</span> of the reflected <span class="hlt">waves</span> from the rigid walls are calculated by using the method of images. The result shows that the phase velocity of the <span class="hlt">pressure</span> <span class="hlt">wave</span> propagating in the liquid containing 10 spherical bubbles in the duct agrees well with the low-frequency speed of sound in a homogeneous bubbly liquid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010HPR....30...88R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010HPR....30...88R"><span>An application of Love SH <span class="hlt">waves</span> for the viscosity measurement of triglycerides at high <span class="hlt">pressures</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rostocki, A. J.; Siegoczyński, R. M.; Kiełczyński, P.; Szalewski, M.</p> <p>2010-03-01</p> <p>A new ultrasonic method of viscosity measurements at a high-<span class="hlt">pressure</span> conditions has been presented. The method is based on the Love <span class="hlt">wave</span> amplitude measurement. The same electronic setup as in the Bleustein-Gulyaev (B-G) <span class="hlt">wave</span> method applied by the authors recently for a high-<span class="hlt">pressure</span> measurement was adopted. The new sensors were made of metallic materials, which make them more reliable at high-<span class="hlt">pressure</span> conditions. The method has been successfully applied for the viscosity measurement of some triglycerides at high-<span class="hlt">pressure</span> conditions up to 1 GPa. The results have been compared with the earlier results obtained using B-G <span class="hlt">waves</span>. This comparison has shown that Love <span class="hlt">wave</span> method sensors are more reliable than B-G <span class="hlt">wave</span> sensors and are also cheaper in fabrication, although the sensitivity of Love <span class="hlt">wave</span> sensors is lower. During the measurement, the phase transitions in the investigated liquids were observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JSV...333.6156M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JSV...333.6156M"><span>Model experiment and analysis of <span class="hlt">pressure</span> <span class="hlt">waves</span> emitted from portals of a tunnel with a branch</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Miyachi, T.; Fukuda, T.; Saito, S.</p> <p>2014-11-01</p> <p>A model experiment was performed to investigate <span class="hlt">pressure</span> <span class="hlt">waves</span> generated by a train passing by a branch and pulse <span class="hlt">waves</span> radiated from portals of a main tunnel and the branch. For the experiment, the train speed was set as 400-500 km/h. The cross-sectional area ratio of the branch to the main tunnel was 0-0.5. The cross-sectional area ratio of the branch to the main tunnel was identified as a dominant factor in determining the magnitude of the <span class="hlt">pressure</span> <span class="hlt">waves</span> in the tunnel and the pulse <span class="hlt">waves</span> radiated from the portals. Closed form expressions for the magnitude of the <span class="hlt">pressure</span> changes generated by a train passing by a branch were derived using low Mach number approximation. Correlation between the <span class="hlt">pressure</span> <span class="hlt">waves</span> in the tunnel and the pulse <span class="hlt">waves</span> radiated from the portals was clarified using simple acoustic theory. The overall tendency of the experimental results is explainable based on analytical results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMNG23A1369S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMNG23A1369S"><span>Experimental particle acceleration by water evaporation <span class="hlt">induced</span> by shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scolamacchia, T.; Alatorre Ibarguengoitia, M.; Scheu, B.; Dingwell, D. B.; Cimarelli, C.</p> <p>2010-12-01</p> <p>Shock <span class="hlt">waves</span> are commonly generated during volcanic eruptions. They <span class="hlt">induce</span> sudden changes in <span class="hlt">pressure</span> and temperature causing phase changes. Nevertheless, their effects on flowfield properties are not well understood. Here we investigate the role of gas expansion generated by shock <span class="hlt">wave</span> propagation in the acceleration of ash particles. We used a shock tube facility consisting of a high-<span class="hlt">pressure</span> (HP) steel autoclave (450 mm long, 28 mm in internal diameter), <span class="hlt">pressurized</span> with Ar gas, and a low-<span class="hlt">pressure</span> tank at atmospheric conditions (LP). A copper diaphragm separated the HP autoclave from a 180 mm tube (PVC or acrylic glass) at ambient P, with the same internal diameter of the HP reservoir. Around the tube, a 30 cm-high acrylic glass cylinder, with the same section of the LP tank (40 cm), allowed the observation of the processes occurring downstream from the nozzle throat, and was large enough to act as an unconfined volume in which the initial diffracting shock and gas jet expand. All experiments were performed at Pres/Pamb ratios of 150:1. Two ambient conditions were used: dry air and air saturated with steam. Carbon fibers and glass spheres in a size range between 150 and 210 μm, were placed on a metal wire at the exit of the PVC tube. The sudden decompression of the Ar gas, due to the failure of the diaphragm, generated an initial air shock <span class="hlt">wave</span>. A high-speed camera recorded the processes between the first 100 μsec and several ms after the diaphragm failure at frame rates ranging between 30,000 and 50,000 fps. In the experiments with ambient air saturated with steam, the high-speed camera allowed to visualize the condensation front associated with the initial air shock; a maximum velocity of 788 m/s was recorded, which decreases to 524 m/s at distance of 0.5 ±0.2 cm, 1.1 ms after the diaphragm rupture. The condensation front preceded the Ar jet front exhausting from the reservoir, by 0.2-0.5 ms. In all experiments particles velocities following the initial</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/sir/2010/5138/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/sir/2010/5138/"><span>Predicting S-<span class="hlt">wave</span> velocities for unconsolidated sediments at low effective <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Lee, Myung W.</p> <p>2010-01-01</p> <p>Accurate S-<span class="hlt">wave</span> velocities for shallow sediments are important in performing a reliable elastic inversion for gas hydrate-bearing sediments and in evaluating velocity models for predicting S-<span class="hlt">wave</span> velocities, but few S-<span class="hlt">wave</span> velocities are measured at low effective <span class="hlt">pressure</span>. Predicting S-<span class="hlt">wave</span> velocities by using conventional methods based on the Biot-Gassmann theory appears to be inaccurate for laboratory-measured velocities at effective <span class="hlt">pressures</span> less than about 4-5 megapascals (MPa). Measured laboratory and well log velocities show two distinct trends for S-<span class="hlt">wave</span> velocities with respect to P-<span class="hlt">wave</span> velocity: one for the S-<span class="hlt">wave</span> velocity less than about 0.6 kilometer per second (km/s) which approximately corresponds to effective <span class="hlt">pressure</span> of about 4-5 MPa, and the other for S-<span class="hlt">wave</span> velocities greater than 0.6 km/s. To accurately predict S-<span class="hlt">wave</span> velocities at low effective <span class="hlt">pressure</span> less than about 4-5 MPa, a <span class="hlt">pressure</span>-dependent parameter that relates the consolidation parameter to shear modulus of the sediments at low effective <span class="hlt">pressure</span> is proposed. The proposed method in predicting S-<span class="hlt">wave</span> velocity at low effective <span class="hlt">pressure</span> worked well for velocities of water-saturated sands measured in the laboratory. However, this method underestimates the well-log S-<span class="hlt">wave</span> velocities measured in the Gulf of Mexico, whereas the conventional method performs well for the well log velocities. The P-<span class="hlt">wave</span> velocity dispersion due to fluid in the pore spaces, which is more pronounced at high frequency with low effective <span class="hlt">pressures</span> less than about 4 MPa, is probably a cause for this discrepancy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.8946E..07N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.8946E..07N"><span>Visualization of ultrasonically <span class="hlt">induced</span> shear <span class="hlt">wave</span> propagation using phase sensitive optical coherence tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nguyen, Thu-Mai; Song, Shaozhen; Arnal, Bastien; Wong, Emily Y.; Wang, Ruikang K.; O'Donnell, Matthew</p> <p>2014-02-01</p> <p>Shear <span class="hlt">wave</span> elastography measures the stiffness of soft tissues from the speed of propagating shear <span class="hlt">waves</span> <span class="hlt">induced</span> in tissue. Optical coherence tomography (OCT) is a promising detection modality given its high sensitivity and spatial resolution, making it suitable for elastic characterization of skin, peripheral vasculature or ocular tissues. For clinical applications, it would be valuable to use a non-contact shear source. Thus, we propose acoustic radiation force as a remote shear source combined with OCT for visualization. A single-element focused transducer (central frequency 7.5 MHz) was used to apply a maximal <span class="hlt">pressure</span> of ~3 MPa for 100 μs in agar phantoms. It <span class="hlt">induced</span> shear <span class="hlt">waves</span> with an amplitude of several hundreds of nanometers and a broadband spectrum in the kilohertz range. Phasesensitive OCT was used to track shear <span class="hlt">waves</span> at an equivalent frame rate of 47 kHz. We reconstructed shear modulus maps in a heterogeneous phantom. In addition, we use 3-ms long coded excitation to increase the displacement signal-to-noise ratio. We applied digital pulse compression to the resulting displacement field to obtain a gain of ~15 dB compared to standard pulse excitation while maintaining the US <span class="hlt">pressure</span> level and the shear <span class="hlt">wave</span> spatial and temporal resolution. This is a promising result for shear <span class="hlt">wave</span> generation at low US <span class="hlt">pressures</span> (~ 1 MPa).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRC..122..153G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRC..122..153G"><span>Vertical structure of pore <span class="hlt">pressure</span> under surface gravity <span class="hlt">waves</span> on a steep, megatidal, mixed sand-gravel-cobble beach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guest, Tristan B.; Hay, Alex E.</p> <p>2017-01-01</p> <p>The vertical structure of surface gravity <span class="hlt">wave-induced</span> pore <span class="hlt">pressure</span> is investigated within the intertidal zone of a natural, steeply sloping, megatidal, mixed sand-gravel-cobble beach. Results from a coherent vertical array of buried pore <span class="hlt">pressure</span> sensors are presented in terms of signal phase lag and attenuation as functions of oscillatory forcing frequency and burial depth. Comparison of the observations with the predictions of a theoretical poro-elastic bed response model indicates that the large observed phase lags and attenuation are attributable to interstitial trapped air. In addition to the dependence on entrapped air volume, the pore <span class="hlt">pressure</span> phase and attenuation are shown to be sensitive to the hydraulic conductivity of the sediment, to the changing mean water depth during the tidal cycle, and to the redistribution/rearrangement of beach face material by energetic <span class="hlt">wave</span> action during storm events. The latter result indicates that the effects on pore <span class="hlt">pressure</span> of sediment column disturbance during instrument burial can persist for days to weeks, depending upon <span class="hlt">wave</span> forcing conditions. Taken together, these results raise serious questions as to the practicality of using pore <span class="hlt">pressure</span> measurements to estimate the kinematic properties of surface gravity <span class="hlt">waves</span> on steep, mixed sand-gravel beaches.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS32A..05G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS32A..05G"><span>Vertical Structure of Pore <span class="hlt">Pressure</span> Under Surface Gravity <span class="hlt">Waves</span> on a Steep, Megatidal, Mixed Sand-Gravel-Cobble Beach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guest, T.; Hay, A. E.</p> <p>2016-12-01</p> <p>The vertical structure of surface gravity <span class="hlt">wave-induced</span> pore <span class="hlt">pressure</span> is investigated within the intertidal zone of a steeply sloping, megatidal, mixed sand-gravel-cobble beach. Results from a coherent vertical array of buried pore <span class="hlt">pressure</span> sensors are presented in terms of signal phase lag and attenuation as functions of frequency and burial depth. Comparison of the observations with the predictions of a theoretical poro-elastic bed response model indicates that the large observed phase lags and attenuation are attributable to interstitial trapped air. In addition to the dependence on entrapped air volume, the pore <span class="hlt">pressure</span> phase and attenuation are shown to be sensitive to the hydraulic conductivity of the sediment, to the changing mean water depth during the tidal cycle, and to the redistribution/rearrangement of beach face material by energetic <span class="hlt">wave</span> action during storm events. The latter result indicates that the effects on pore <span class="hlt">pressure</span> of sediment column disturbance during instrument burial can persist for days to weeks, depending upon <span class="hlt">wave</span> forcing conditions. Taken together, these results raise serious questions as to the practicality of using pore <span class="hlt">pressure</span> measurements to estimate the kinematic properties of surface gravity <span class="hlt">waves</span> on steep, mixed sand-gravel beaches.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25510830','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25510830"><span>Indexes of aortic <span class="hlt">pressure</span> augmentation markedly underestimate the contribution of reflected <span class="hlt">waves</span> toward variations in aortic <span class="hlt">pressure</span> and left ventricular mass.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Booysen, Hendrik L; Woodiwiss, Angela J; Sibiya, Moekanyi J; Hodson, Bryan; Raymond, Andrew; Libhaber, Elena; Sareli, Pinhas; Norton, Gavin R</p> <p>2015-03-01</p> <p>Although indexes of <span class="hlt">wave</span> reflection enhance risk prediction, the extent to which measures of aortic systolic <span class="hlt">pressure</span> augmentation (augmented <span class="hlt">pressures</span> [Pa] or augmentation index) underestimate the effects of reflected <span class="hlt">waves</span> on cardiovascular risk is uncertain. In participants from a community sample (age >16), we compared the relative contribution of reflected (backward <span class="hlt">wave</span> <span class="hlt">pressures</span> and the reflected <span class="hlt">wave</span> index [RI]) versus augmented (Pa and augmentation index) <span class="hlt">pressure</span> <span class="hlt">wave</span> indexes to variations in central aortic pulse <span class="hlt">pressure</span> (PPc; n=1185), and left ventricular mass index (LVMI; n=793). Aortic hemodynamics and LVMI were determined using radial applanation tonometry (SphygmoCor) and echocardiography. Independent of confounders, RI and backward <span class="hlt">wave</span> <span class="hlt">pressures</span> contributed more than forward <span class="hlt">wave</span> <span class="hlt">pressures</span>, whereas Pa and augmentation index contributed less than incident <span class="hlt">wave</span> <span class="hlt">pressure</span> to variations in PPc (P<0.0001 for comparison of partial r values). In those <50 years of age, while backward <span class="hlt">wave</span> <span class="hlt">pressures</span> (partial r=0.28, P<0.0001) contributed more than forward <span class="hlt">wave</span> <span class="hlt">pressures</span> (partial r=0.15, P<0.001; P<0.05 for comparison of r values), Pa (partial r=0.13, P<0.005) contributed to a similar extent as incident <span class="hlt">wave</span> <span class="hlt">pressure</span> (partial r=0.22, P<0.0001) to variations in LVMI. Furthermore, in those ≥50 years of age, backward <span class="hlt">wave</span> <span class="hlt">pressures</span> (partial r=0.21, P<0.0001), but not forward <span class="hlt">wave</span> <span class="hlt">pressures</span> (P=0.98), while incident <span class="hlt">wave</span> <span class="hlt">pressure</span> (partial r=0.23, P<0.0001), but not Pa (P=0.80) were associated with LVMI. Pa and augmentation index underestimated the effect of <span class="hlt">wave</span> reflection on PPc and LVMI in both men and women. Thus, as compared with relations between indexes of aortic <span class="hlt">pressure</span> augmentation and PPc or LVMI, strikingly better relations are noted between aortic <span class="hlt">wave</span> reflection and PPc or LVMI. © 2014 American Heart Association, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AIPC.1195.1265R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AIPC.1195.1265R"><span>High-<span class="hlt">Pressure</span> Range Shock <span class="hlt">Wave</span> Data for Syntactic Foams</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ribeiro, J.; Mendes, R.; Plaksin, I.; Campos, J.; Capela, C.</p> <p>2009-12-01</p> <p>Syntactic foams [SF] are a porous composite material resulting from the mixture of Hollow Glass Micro Spheres [HGMS] with a polymeric binder. Beyond a set of technological advantages over the polymer considered alone, SF present as an essential feature the possibility to control in wide limits the amount, the shape and the size of the pores and for that reason are being used for benchmarking in the area of shock <span class="hlt">wave</span> [SW] behavior of porous materials. In this paper, SW loading experiments of SF samples were performed in order to assess the high-<span class="hlt">pressure</span> range Hugoniot equation of state as a function of the SF initial density. Hugoniot data were assessed coupling the SW velocity within the SF samples with the SW velocity in a reference material or with manganin gauge results. The results obtained present a significant variation with the initial specific mass and can be described with appreciable precision by the Thouvenin/Hofmann Plate Gap model, while the concordance between the experimental results and the Grüneisen model seems to be very dependent on the Grüneisen coefficient values.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20960188','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20960188"><span>Enhancement of terahertz <span class="hlt">wave</span> generation from laser <span class="hlt">induced</span> plasma</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xie Xu; Xu Jingzhou; Dai Jianming; Zhang, X.-C.</p> <p>2007-04-02</p> <p>It is well known that air plasma <span class="hlt">induced</span> by ultrashort laser pulses emits broadband terahertz <span class="hlt">waves</span>. The authors report the study of terahertz <span class="hlt">wave</span> generation from the laser <span class="hlt">induced</span> plasma where there is a preexisting plasma background. When a laser beam from a Ti:sapphire amplifier is used to generate a terahertz <span class="hlt">wave</span>, enhancement of the generation is observed if there is another laser beam creating a plasma background. The enhancement of the terahertz <span class="hlt">wave</span> amplitude lasts hundreds of picoseconds after the preionized background is created, with a maximum enhancement up to 250% observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22698515','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22698515"><span>Supersonic shear <span class="hlt">wave</span> elastography of in vivo pig kidney: influence of blood <span class="hlt">pressure</span>, urinary <span class="hlt">pressure</span> and tissue anisotropy.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gennisson, Jean-Luc; Grenier, Nicolas; Combe, Christian; Tanter, Mickaël</p> <p>2012-09-01</p> <p>The in vivo influence of renal anisotropy and of urinary and vascular <span class="hlt">pressure</span> on elasticity values using ultrasonic supersonic shear <span class="hlt">wave</span> elastography was studied in pigs. Experiments were conducted in agreement with the European Commission guidelines and directives of the French Research Ministry. Six kidneys in three pigs were studied in vivo. Elasticity of renal cortex and medulla was quantified through the shear modulus (μ) by using the supersonic shear imaging technique with an 8 MHz linear ultrasound probe. All measurements were done peroperatively both in the axis and perpendicular to the main axis of pyramids, in normal condition, after progressive increase of urinary <span class="hlt">pressure</span>, and after renal artery and renal vein ligation. In normal conditions, cortical (C) and medullary (M) elasticity values were always higher when acquisitions were realized with the ultrasound main axis perpendicular to main pyramid axis (C(//): 7.7 ± 2.3 kPa; M(//): 8.7 ± 2.5 kPa) than parallel (C(⊥): 6.9 ± 1.4 kPa; M(⊥): 6.6 ± 2.3 kPa), demonstrating an effect of renal anisotropy. In renal cortex, two bands were separated, inner cortex showing higher elasticity values (IC(⊥): 8.1 ± 1.9 kPa) than outer cortex (OC(⊥): 6.9 ± 1.4 kPa). Renal artery and renal vein ligation <span class="hlt">induced</span> a decrease and an increase of elasticity respectively. Parenchymal elasticity increased linearly with elevation of urinary <span class="hlt">pressure</span>. Intrarenal elasticity values vary with tissue anisotropy and, with vascular and urinary <span class="hlt">pressure</span> levels. These parameters have to be taken into account for interpretation of tissue changes. Separation of outer and inner cortex could be attributable to perfusion differences.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28366710','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28366710"><span>Ultrasound Shear <span class="hlt">Wave</span> Elastography: A Novel Method to Evaluate Bladder <span class="hlt">Pressure</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sturm, Renea M; Yerkes, Elizabeth B; Nicholas, Jennifer L; Snow-Lisy, Devon; Diaz Saldano, Dawn; Gandor, P Lacy; Halline, Christopher G; Rosoklija, Ilina; Rychlik, Karen; Johnson, Emilie K; Cheng, Earl Y</p> <p>2017-03-31</p> <p>Children with bladder dysfunction resulting in increased storage <span class="hlt">pressure</span> are at risk for renal deterioration. The current gold standard for evaluation of bladder <span class="hlt">pressure</span> is urodynamics, an invasive test requiring catheterization. We evaluated ultrasound shear <span class="hlt">wave</span> elastography as a novel means of assessing bladder biomechanical properties associated with increased bladder <span class="hlt">pressure</span>. Concurrent shear <span class="hlt">wave</span> elastography and urodynamics were performed. Ultrasound shear <span class="hlt">wave</span> elastography images were obtained of the anterior and posterior wall when empty and at 25%, 50%, 75% and 100% expected bladder capacity, and end fill volume. Regions of interest were confirmed by a pediatric radiologist. Bladder cohorts were defined as compliant (capacity detrusor <span class="hlt">pressure</span> less than 25 cm H2O) and noncompliant (25 cm H2O or greater). Pearson correlation coefficients and a mixed effects model evaluated the relationship between shear <span class="hlt">wave</span> speed and detrusor <span class="hlt">pressure</span>, compliance and normalized compliance. An unpaired t-test was used for between cohort analyses. In all 23 subjects mean shear <span class="hlt">wave</span> speed of the anterior and posterior bladder walls significantly correlated with detrusor <span class="hlt">pressure</span> throughout filling. When comparing compliant and noncompliant bladders, mean shear <span class="hlt">wave</span> speed and detrusor shear <span class="hlt">wave</span> speed of the anterior wall significantly increased with filling of noncompliant bladders. Shear <span class="hlt">wave</span> speed remained at baseline levels in compliant bladders. Mean shear <span class="hlt">wave</span> speed of the anterior wall was significantly correlated with compliance and normalized compliance. Ultrasound shear <span class="hlt">wave</span> elastography bladder measurements correlate well with bladder storage <span class="hlt">pressure</span>, and shear <span class="hlt">wave</span> speed measurements differ between compliant and noncompliant bladders. This is the first known study to demonstrate that shear <span class="hlt">wave</span> elastography is promising as a bedside modality for the assessment of bladder dysfunction in children. Copyright © 2017 American Urological Association Education and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MsT.........21P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MsT.........21P"><span>Numerical modeling and characterization of blast <span class="hlt">waves</span> for application in blast-<span class="hlt">induced</span> mild traumatic brain injury research</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Phillips, Michael G.</p> <p></p> <p>Human exposure to blast <span class="hlt">waves</span>, including blast-<span class="hlt">induced</span> traumatic brain injury, is a developing field in medical research. Experiments with explosives have many disadvantages including safety, cost, and required area for trials. Shock tubes provide an alternative method to produce free field blast <span class="hlt">wave</span> profiles. A compressed nitrogen shock tube experiment instrumented with static and reflective <span class="hlt">pressure</span> taps is modeled using a numerical simulation. The geometry of the numerical model is simplified and blast <span class="hlt">wave</span> characteristics are derived based upon static and <span class="hlt">pressure</span> profiles. The <span class="hlt">pressure</span> profiles are analyzed along the shock tube centerline and radially away from the tube axis. The blast <span class="hlt">wave</span> parameters found from the <span class="hlt">pressure</span> profiles provide guidelines for spatial location of a specimen. The location could be based on multiple parameters and provides a distribution of anticipated <span class="hlt">pressure</span> profiles experience by the specimen.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21129403','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21129403"><span>Relationship between orientation to a blast and <span class="hlt">pressure</span> <span class="hlt">wave</span> propagation inside the rat brain.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chavko, Mikulas; Watanabe, Tomas; Adeeb, Saleena; Lankasky, Jason; Ahlers, Stephen T; McCarron, Richard M</p> <p>2011-01-30</p> <p>Exposure to a blast <span class="hlt">wave</span> generated during an explosion may result in brain damage and related neurological impairments. Several mechanisms by which the primary blast <span class="hlt">wave</span> can damage the brain have been proposed, including: (1) a direct effect of the shock <span class="hlt">wave</span> on the brain causing tissue damage by skull flexure and propagation of stress and shear forces; and (2) an indirect transfer of kinetic energy from the blast, through large blood vessels and cerebrospinal fluid (CSF), to the central nervous system. To address a basic question related to the mechanisms of blast brain injury, <span class="hlt">pressure</span> was measured inside the brains of rats exposed to a low level of blast (~35kPa), while positioned in three different orientations with respect to the primary blast <span class="hlt">wave</span>; head facing blast, right side exposed to blast and head facing away from blast. Data show different patterns and durations of the <span class="hlt">pressure</span> traces inside the brain, depending on the rat orientation to blast. Frontal exposures (head facing blast) resulted in <span class="hlt">pressure</span> traces of higher amplitude and longer duration, suggesting direct transmission and reflection of the <span class="hlt">pressure</span> inside the brain (dynamic <span class="hlt">pressure</span> transfer). The pattern of the <span class="hlt">pressure</span> <span class="hlt">wave</span> inside the brain in the head facing away from blast exposures assumes contribution of the static <span class="hlt">pressure</span>, similar to hydrodynamic <span class="hlt">pressure</span> to the <span class="hlt">pressure</span> <span class="hlt">wave</span> inside the brain. Published by Elsevier B.V.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26988153','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26988153"><span>Characteristic enhancement of blood <span class="hlt">pressure</span> V-shaped <span class="hlt">waves</span> in sinoaortic-denervated rats in a conscious and quiet state.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chang, Huan; Gu, Hong-Xia; Gong, Min; Han, Ji-Ju; Wang, Yun; Xia, Zuo-Li; Zhao, Xiao-Min</p> <p>2016-11-08</p> <p>A hemodynamic feature of chronic sinoaortic-denervated (SAD) rats is the increase in blood <span class="hlt">pressure</span> variability (BPV) without significant changes in the average level of blood <span class="hlt">pressure</span> (BP). The current study was designed to investigate the changes in BP V-shaped <span class="hlt">waves</span> (V <span class="hlt">waves</span>) in SAD rats. Sprague-Dawley (SD) rats were divided into 2 groups: SAD rats and sham-operated rats (n=13). Hemodynamics measurements were obtained in conscious, freely moving rats, four weeks after sinoaortic denervation or sham operation. V <span class="hlt">wave</span> indices were evaluated in rats in both conscious and quiet states. Additionally, normal and high BPV was simulated by the production of V <span class="hlt">waves</span> with different amplitudes. The results showed that the V <span class="hlt">wave</span> amplitude was dramatically increased, with a significantly prolonged duration and reduced frequency in SAD rats. V <span class="hlt">wave</span> BPV in SAD rats was significantly increased, though BP remained unchanged. The twenty-four hour BPV in all rats was positively correlated with amplitude, duration time and V <span class="hlt">wave</span> BPV and negatively correlated with frequency. The systolic BP spectral powers in the low frequency range (0.38-0.45 Hz) were significantly reduced in the V <span class="hlt">waves</span> of SAD rats. Moreover, there was a remarkable increase in mean BPV and a normal mean BP after simulating high BPV in SAD rats. These results suggest that enhancement of V <span class="hlt">waves</span> might be a waveform character of BP in SAD rats in both the conscious and quiet states. These types of V <span class="hlt">waves</span> appear to be related to a depression of sympathetic regulation of BP <span class="hlt">induced</span> by sinoaortic denervation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA111186','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA111186"><span>Statistical Description of <span class="hlt">Wave</span> <span class="hlt">Induced</span> Vibratory Stresses in Ships.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1980-12-01</p> <p>AD-Aill 186 NORSKE VERITAS OSLO FIG 13/10 STATISTICAL DESCRIPTION OF <span class="hlt">WAVE</span> <span class="hlt">INDUCED</span> VIBRATORY STRESSES IN S--ETC(U) I DEC 80 S GRAN DTC623-80-C-20007...UNCLASSIFIED 80-1171 USCG-M-2-81 NL Ummli.mm....m REPORT NO. CG-M-2-814 STATISTICAL DESCRIPTION OF <span class="hlt">WAVE</span> <span class="hlt">INDUCED</span> VIBRATORY STRESSES IN SHIPS Sverre Gran...Ttle anld Si ,fb.le 5. Roer, Dole December 1980 Statistical Description of <span class="hlt">Wave</span> <span class="hlt">Induced</span> Decmber 1980 Vibratory Stresses in Ships 6. Pef om.. O,’gOr n</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960021372&hterms=stratified&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dstratified','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960021372&hterms=stratified&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dstratified"><span>Alfven <span class="hlt">wave</span> resonances and flow <span class="hlt">induced</span> by non-linear Alfven <span class="hlt">waves</span> in a stratified atmosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stark, B. A.; Musielak, Z. E.; Suess, S. T.</p> <p>1995-01-01</p> <p>A nonlinear, time-dependent, ideal MHD code has been developed and used to compute the flow <span class="hlt">induced</span> by nonlinear Alfven <span class="hlt">waves</span> propagating in an isothermal, stratified, plane-parallel atmosphere. The code is based on characteristic equations solved in a Lagrangian frame and is highly accurate. Results show that resonance behavior of Alfven <span class="hlt">waves</span> exists in the presence of a continuous density gradient and that the <span class="hlt">waves</span> with periods corresponding to resonant peaks exert considerably more force on the medium than off-resonance periods; this leads to enhanced flow. If only off-peak periods are considered, the relationship between the <span class="hlt">wave</span> period and <span class="hlt">induced</span> longitudinal velocity shows that short period WKB <span class="hlt">waves</span> push more on the background medium than longer period, non-WKB, <span class="hlt">waves</span>. The results also show the development of the longitudinal <span class="hlt">waves</span> produced by the finite amplitude of the Alfven <span class="hlt">waves</span>. The longitudinal <span class="hlt">wave</span> becomes strong as the Alfven <span class="hlt">wave</span> relative amplitude grows above 10 percent and will lead to strong damping of the Alfven <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25215810','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25215810"><span>Rogue-<span class="hlt">wave</span> pattern transition <span class="hlt">induced</span> by relative frequency.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhao, Li-Chen; Xin, Guo-Guo; Yang, Zhan-Ying</p> <p>2014-08-01</p> <p>We revisit a rogue <span class="hlt">wave</span> in a two-mode nonlinear fiber whose dynamics is described by two-component coupled nonlinear Schrödinger equations. The relative frequency between two modes can <span class="hlt">induce</span> different rogue <span class="hlt">wave</span> patterns transition. In particular, we find a four-petaled flower structure rogue <span class="hlt">wave</span> can exist in the two-mode coupled system, which possesses an asymmetric spectrum distribution. Furthermore, spectrum analysis is performed on these different type rogue <span class="hlt">waves</span>, and the spectrum relations between them are discussed. We demonstrate qualitatively that different modulation instability gain distribution can <span class="hlt">induce</span> different rogue <span class="hlt">wave</span> excitation patterns. These results would deepen our understanding of rogue <span class="hlt">wave</span> dynamics in complex systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..4311024M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..4311024M"><span>Identification of rocket-<span class="hlt">induced</span> acoustic <span class="hlt">waves</span> in the ionosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mabie, Justin; Bullett, Terence; Moore, Prentiss; Vieira, Gerald</p> <p>2016-10-01</p> <p>Acoustic <span class="hlt">waves</span> can create plasma disturbances in the ionosphere, but the number of observations is limited. Large-amplitude acoustic <span class="hlt">waves</span> generated by energetic sources like large earthquakes and tsunamis are more readily observed than acoustic <span class="hlt">waves</span> generated by weaker sources. New observations of plasma displacements caused by rocket-generated acoustic <span class="hlt">waves</span> were made using the Vertically Incident Pulsed Ionospheric Radar (VIPIR), an advanced high-frequency radar. Rocket-<span class="hlt">induced</span> acoustic <span class="hlt">waves</span> which are characterized by low amplitudes relative to those <span class="hlt">induced</span> by more energetic sources can be detected in the ionosphere using the phase data from fixed frequency radar observations of a plasma layer. This work is important for increasing the number and quality of observations of acoustic <span class="hlt">waves</span> in the ionosphere and could help improve the understanding of energy transport from the lower atmosphere to the thermosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhRvE..90b2918Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhRvE..90b2918Z"><span>Rogue-<span class="hlt">wave</span> pattern transition <span class="hlt">induced</span> by relative frequency</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Li-Chen; Xin, Guo-Guo; Yang, Zhan-Ying</p> <p>2014-08-01</p> <p>We revisit a rogue <span class="hlt">wave</span> in a two-mode nonlinear fiber whose dynamics is described by two-component coupled nonlinear Schrödinger equations. The relative frequency between two modes can <span class="hlt">induce</span> different rogue <span class="hlt">wave</span> patterns transition. In particular, we find a four-petaled flower structure rogue <span class="hlt">wave</span> can exist in the two-mode coupled system, which possesses an asymmetric spectrum distribution. Furthermore, spectrum analysis is performed on these different type rogue <span class="hlt">waves</span>, and the spectrum relations between them are discussed. We demonstrate qualitatively that different modulation instability gain distribution can <span class="hlt">induce</span> different rogue <span class="hlt">wave</span> excitation patterns. These results would deepen our understanding of rogue <span class="hlt">wave</span> dynamics in complex systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016CNSNS..34...66A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016CNSNS..34...66A"><span>Rogue <span class="hlt">wave</span> formation under the action of quasi-stationary <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abrashkin, A. A.; Oshmarina, O. E.</p> <p>2016-05-01</p> <p>The process of rogue <span class="hlt">wave</span> formation on deep water is considered. A <span class="hlt">wave</span> of extreme amplitude is born against the background of uniform <span class="hlt">waves</span> (Gerstner <span class="hlt">waves</span>) under the action of external <span class="hlt">pressure</span> on free surface. The <span class="hlt">pressure</span> distribution has a form of a quasi-stationary "pit". The fluid motion is supposed to be a vortex one and is described by an exact solution of equations of 2D hydrodynamics for an ideal fluid in Lagrangian coordinates. Liquid particles are moving around circumferences of different radii in the absence of drift flow. Values of amplitude and <span class="hlt">wave</span> steepness optimal for rogue <span class="hlt">wave</span> formation are found numerically. The influence of vorticity distribution and <span class="hlt">pressure</span> drop on parameters of the fluid is investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22490073','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22490073"><span>Nonlinear upper hybrid <span class="hlt">waves</span> and the <span class="hlt">induced</span> density irregularities</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kuo, Spencer P.</p> <p>2015-08-15</p> <p>Upper hybrid <span class="hlt">waves</span> are excited parametrically by the O-mode high-frequency heater <span class="hlt">waves</span> in the ionospheric heating experiments. These <span class="hlt">waves</span> grow to large amplitudes and self-<span class="hlt">induced</span> density perturbations provide nonlinear feedback. The lower hybrid resonance modifies the nonlinear feedback driven by the ponderomotive force; the nonlinear equation governing the envelope of the upper hybrid <span class="hlt">waves</span> is derived. Solutions in symmetric alternating functions, in non-alternating periodic functions, as well as in solitary functions are shown. The impact of lower hybrid resonance on the envelope of the upper hybrid <span class="hlt">waves</span> is explored; the results show that both the spatial period and amplitude are enlarged. The average fluctuation level of <span class="hlt">induced</span> density irregularities is also enhanced. In the soliton form, the <span class="hlt">induced</span> density cavity is widened considerably.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE.9805E..0OW','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE.9805E..0OW"><span>Defect <span class="hlt">induced</span> guided <span class="hlt">waves</span> mode conversion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wandowski, Tomasz; Kudela, Pawel; Malinowski, Pawel; Ostachowicz, Wieslaw</p> <p>2016-04-01</p> <p>This paper deals with analysis of guided <span class="hlt">waves</span> mode conversion phenomenon in fiber reinforced composite materials. Mode conversion phenomenon may take place when propagating elastic guided <span class="hlt">waves</span> interact with discontinuities in the composite waveguide. The examples of such discontinuities are sudden thickness change or delamination between layers in composite material. In this paper, analysis of mode conversion phenomenon is based on full <span class="hlt">wave</span>-field signals. In the full <span class="hlt">wave</span>-field approach signals representing propagation of elastic <span class="hlt">waves</span> are gathered from dense mesh of points that span over investigated area of composite part. This allow to animate the guided <span class="hlt">wave</span> propagation. The reported analysis is based on signals resulting from numerical calculations and experimental measurements. In both cases defect in the form of delamination is considered. In the case of numerical research, Spectral Element Method (SEM) is utilized, in which a mesh is composed of 3D elements. Numerical model includes also piezoelectric transducer. Full <span class="hlt">wave</span>-field experimental measurements are conducted by using piezoelectric transducer for guided <span class="hlt">wave</span> excitation and Scanning Laser Doppler Vibrometer (SLDV) for sensing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1336594','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1336594"><span>Spin-transfer torque <span class="hlt">induced</span> spin <span class="hlt">waves</span> in antiferromagnetic insulators</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Daniels, Matthew W.; Guo, Wei; Stocks, George Malcolm; Xiao, Di; Xiao, Jiang</p> <p>2015-01-01</p> <p>We explore the possibility of exciting spin <span class="hlt">waves</span> in insulating antiferromagnetic films by injecting spin current at the surface. We analyze both magnetically compensated and uncompensated interfaces. We find that the spin current <span class="hlt">induced</span> spin-transfer torque can excite spin <span class="hlt">waves</span> in insulating antiferromagnetic materials and that the chirality of the excited spin <span class="hlt">wave</span> is determined by the polarization of the injected spin current. Furthermore, the presence of magnetic surface anisotropy can greatly increase the accessibility of these excitations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1336594-spin-transfer-torque-induced-spin-waves-antiferromagnetic-insulators','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1336594-spin-transfer-torque-induced-spin-waves-antiferromagnetic-insulators"><span>Spin-transfer torque <span class="hlt">induced</span> spin <span class="hlt">waves</span> in antiferromagnetic insulators</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Daniels, Matthew W.; Guo, Wei; Stocks, George Malcolm; ...</p> <p>2015-01-01</p> <p>We explore the possibility of exciting spin <span class="hlt">waves</span> in insulating antiferromagnetic films by injecting spin current at the surface. We analyze both magnetically compensated and uncompensated interfaces. We find that the spin current <span class="hlt">induced</span> spin-transfer torque can excite spin <span class="hlt">waves</span> in insulating antiferromagnetic materials and that the chirality of the excited spin <span class="hlt">wave</span> is determined by the polarization of the injected spin current. Furthermore, the presence of magnetic surface anisotropy can greatly increase the accessibility of these excitations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19720052365&hterms=pore+pressure+transducer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dpore%2Bpressure%2Btransducer','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19720052365&hterms=pore+pressure+transducer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dpore%2Bpressure%2Btransducer"><span>Effect of pore <span class="hlt">pressure</span> on the velocity of compressional <span class="hlt">waves</span> in low-porosity rocks.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Todd, T.; Simmons, G.</p> <p>1972-01-01</p> <p>The velocity V sub p of compressional <span class="hlt">waves</span> has been measured in rock samples of low porosity to confining <span class="hlt">pressures</span> P sub c of 2 kb for a number of different constant pore <span class="hlt">pressures</span> P sub p. An effective <span class="hlt">pressure</span> defined by P sub e = P sub c-nP sub p, n less than or equal to 1, is found to be the determining factor in the behavior of V sub p rather than an effective <span class="hlt">pressure</span> defined simply by the differential <span class="hlt">pressure</span> Delta P = P sub c-P sub p. As pore <span class="hlt">pressure</span> increases at constant effective <span class="hlt">pressure</span>, the value of n increases and approaches 1, but as effective <span class="hlt">pressure</span> increases at constant pore <span class="hlt">pressure</span>, the value of n decreases. These observations are consistent with Biot's theory of the propagation of elastic <span class="hlt">waves</span> in a fluid-saturated porous solid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JGRC..115.3022S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JGRC..115.3022S"><span>Mass transport <span class="hlt">induced</span> by internal Kelvin <span class="hlt">waves</span> beneath shore-fast ice</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>StøYlen, Eivind; Weber, Jan Erik H.</p> <p>2010-03-01</p> <p>A one-layer reduced-gravity model is used to investigate the <span class="hlt">wave-induced</span> mass flux in internal Kelvin <span class="hlt">waves</span> along a straight coast beneath shore-fast ice. The <span class="hlt">waves</span> are generated by barotropic tidal pumping at narrow sounds, and the ice lid introduces a no-slip condition for the horizontal <span class="hlt">wave</span> motion. The mean Lagrangian fluxes to second order in <span class="hlt">wave</span> steepness are obtained by integrating the equations of momentum and mass between the material interface and the surface. The mean flow is forced by the conventional radiation stress for internal <span class="hlt">wave</span> motion, the mean <span class="hlt">pressure</span> gradient due to the sloping surface, and the frictional drag at the boundaries. The equations that govern the mean fluxes are expressed in terms of mean Eulerian variables, while the <span class="hlt">wave</span> forcing terms are given by the horizontal divergence of the Stokes flux. Analytical results show that the effect of friction <span class="hlt">induces</span> a mean Eulerian flux along the coast that is comparable to the Stokes flux. In addition, the horizontal divergence of the total mean flux along the coast <span class="hlt">induces</span> a small mass flux in the cross-shore direction. This flux changes the mean thickness of the upper layer outside the trapping region and may facilitate geostrophically balanced boundary currents in enclosed basins. This is indeed demonstrated by numerical solutions of the flux equations for confined areas larger than the trapping region. Application of the theory to Arctic waters is discussed, with emphasis on the transport of biological material and pollutants in nearshore regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990PhRvB..41.7440G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990PhRvB..41.7440G"><span><span class="hlt">Pressure-induced</span> s-->d transfer and the equation of state of molybdenum</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Godwal, B. K.; Jeanloz, Raymond</p> <p>1990-04-01</p> <p>The equations of state of crystalline (bcc) and liquid molybdenum are calculated to <span class="hlt">pressure</span>-temperature conditions of 600 GPa and 14 000 K with use of the linear muffin-tin orbitals (LMTO) model and corrected rigid-ion sphere (CRIS) model. Our results agree with those of previous work in documenting a <span class="hlt">pressure-induced</span> shift of electrons from 5s to 4d states, especially above 100 GPa. An analysis of ultrasonic and shock-<span class="hlt">wave</span> measurements, along with our theoretical findings, documents that the compressibility of bcc Mo becomes enhanced at <span class="hlt">pressures</span> of 100-200 GPa. The enhanced compression, and possibly an anomalous increase in rigidity, are caused by the <span class="hlt">pressure-induced</span> s-->d transfer. Our study reinforces the use of the Mo equation of state as a calibration standard for ultrahigh-<span class="hlt">pressure</span> static experiments and, in particular, for the ruby-fluorescence technique.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007APS..DFD.EL009I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007APS..DFD.EL009I"><span>The Generation of <span class="hlt">Pressure</span> <span class="hlt">Waves</span> by the Implosion of Light Bulbs in a High-<span class="hlt">Pressure</span> Water Environment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ikeda, C.; Czechanowski, M.; Duncan, J. H.</p> <p>2007-11-01</p> <p>The implosion of light bulbs in a high-<span class="hlt">pressure</span> water environment was studied experimentally in a nearly spherical implosion tank with a nominal internal diameter of 1.77 m. During an experimental run, the light bulb was tethered in the center of the tank which was then filled with water and slowly <span class="hlt">pressurized</span> by adding nitrogen gas into a small ullage above the water. The gas <span class="hlt">pressure</span> in the ullage was measured with a slow response transducer and the high-frequency <span class="hlt">pressure</span> <span class="hlt">waves</span> in the water were recorded at 14 positions in the tank with underwater blast sensors. The motion of the light bulb was recorded with a high-speed digital movie camera. The implosions occurred at ambient <span class="hlt">pressures</span> (Pa) ranging from 6.1 bar to 11.6 bar. The collapse times of the light bulbs were found to be about 1.3 times the theoretical collapse time of a spherical bubble at the same ambient <span class="hlt">pressure</span> and with the same radius as the light bulb. The ratio of the peak <span class="hlt">pressure</span> increase due to the <span class="hlt">pressure</span> <span class="hlt">wave</span> at a fixed distance (r) from the bubble to the ambient <span class="hlt">pressure</span> at implosion ((P(r)-Pa)/Pa) increased from about 0.5 to 2.7 as the ambient <span class="hlt">pressure</span> increased over the above-mentioned range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013OcDyn..63.1151L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013OcDyn..63.1151L"><span>Numerical study on <span class="hlt">wave</span> dynamics and <span class="hlt">wave-induced</span> bed erosion characteristics in Potter Cove, Antarctica</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lim, Chai Heng; Lettmann, Karsten; Wolff, Jörg-Olaf</p> <p>2013-12-01</p> <p><span class="hlt">Wave</span> generation, propagation, and transformation from deep ocean over complex bathymetric terrains to coastal waters around Potter Cove (King George Island, South Shetland Islands, Antarctica) have been simulated for an austral summer month using the Simulating <span class="hlt">Waves</span> Nearshore (SWAN) <span class="hlt">wave</span> model. This study aims to examine and understand the <span class="hlt">wave</span> patterns, energy fluxes, and dissipations in Potter Cove. Bed shear stress due to <span class="hlt">waves</span> is also calculated to provide a general insight on the bed sediment erosion characteristics in Potter Cove.A nesting approach has been implemented from an oceanic scale to a high-resolution coastal scale around Potter Cove. The results of the simulations were compared with buoy observations obtained from the National Data Buoy Center, the WAVEWATCH III model results, and Glob<span class="hlt">Wave</span> altimeter data. The quality of the modelling results has been assessed using two statistical parameters, namely the Willmott's index of agreement D and the bias index. Under various <span class="hlt">wave</span> conditions, the significant <span class="hlt">wave</span> heights at the inner cove were found to be about 40-50 % smaller than the ones near the mouth of Potter Cove. The <span class="hlt">wave</span> power in Potter Cove is generally low. The spatial distributions of the <span class="hlt">wave-induced</span> bed shear stress and active energy dissipation were found to be following the pattern of the bathymetry, and <span class="hlt">waves</span> were identified as a potential major driving force for bed sediment erosion in Potter Cove, especially in shallow water regions. This study also gives some results on global ocean applications of SWAN.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.9586W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.9586W"><span>Seismically <span class="hlt">induced</span> <span class="hlt">pressure</span> transients at geothermal reservoirs in the eastern Marmara region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Woith, Heiko; Wang, Rongjiang; Caka, Deniz; Irmak, T. Serkan; Tunc, Berna; Luehr, Birger-G.; Baris, Serif</p> <p>2014-05-01</p> <p>The potential role of fluids in processes related to the triggering of earthquakes and volcanic eruptions is frequently emphasized. Here, we focus on the response of hydrogeological systems to earthquakes, specifically on seismically <span class="hlt">induced</span> pore-<span class="hlt">pressure</span> variations in geothermal areas located in the eastern Marmara region. At a 500 m deep artesian geothermal well the <span class="hlt">pressure</span> is continuously being monitored at a sampling rate of 100 Hz. A seismometer is co-located close to the well-head and the data are recorded by the same digitizer. Hydro-seismograms were recorded in relation to local and distant earthquakes. The ML=5.2 Manyas earthquake which occurred on 20 October 2006 at a distance of 77 km led to a dynamic response of the pore <span class="hlt">pressure</span> of the order of 4 mbar triggered upon the arrival of the S-<span class="hlt">wave</span>. Four days later, the ML=5.2 Gemlik earthquake at a distance of 20 km led to a dynamic pore <span class="hlt">pressure</span> response of the order of 15 mbar triggered upon the arrival of the P-<span class="hlt">wave</span>. In both cases the peak amplitude of the ground velocity was about 2 mm/s. Weak oscillations of the pore <span class="hlt">pressure</span> were observed during the passage of surface <span class="hlt">waves</span> generated by remote earthquakes at distances of up to 9,000 km. Additionally to the dynamic response, a small persistent <span class="hlt">pressure</span> increase of 1 and 2 mbar had been recorded after both local earthquakes. According to preliminary results, the observed <span class="hlt">pressure</span> increase is opposite to the static <span class="hlt">pressure</span> decrease predicted by Okada's model. At the present stage we conclude that the response of the Armutlu geothermal system to earthquakes is likely caused by a dynamic interaction of passing seismic <span class="hlt">waves</span> (P-, S-, and surface <span class="hlt">waves</span>) with the fluid reservoir in case a threshold of the ground shaking is exceeded.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20391918','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20391918"><span>[A calibrated method for blood <span class="hlt">pressure</span> measurement based on volume pulse <span class="hlt">wave</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Youde, Ding; Qinkai, Deng; Feixue, Liang; Jinseng, Guo</p> <p>2010-01-01</p> <p>Physiology parameters measurement based on volume pulse <span class="hlt">wave</span> is suitable for the monitoring blood <span class="hlt">pressure</span> continuously. This paper described that the systolic blood <span class="hlt">pressure</span> (SBP) and diastolic blood <span class="hlt">pressure</span> (DBP) can be calibrated by measuring the pulse propagation time, just on one point of finger tip. The volume pulse <span class="hlt">wave</span> was acquired by lighting the red and infrared LED alternately, and after signal processing, an accelerated pulse <span class="hlt">wave</span> was obtained. Then by measuring the pulse <span class="hlt">wave</span> propagation time between the progressive <span class="hlt">wave</span> and reflected <span class="hlt">wave</span>, we can find the relationship of the time and the blood <span class="hlt">pressure</span>, and establish the related systolic blood <span class="hlt">pressure</span> measurement equation. At the same time, based on the relationship between alternating current and direct current components in the volume pulse waveforms and through regression analysising, the relevant diastolic blood <span class="hlt">pressure</span> measurement equation can be established. 33 clinical experimentation cases have been worked by dividing them into two groups: training group (18 cases) and control group (15 cases), by comparing with the measuring results of the OMRON electronic sphygmomanometer. The results indicated that the two methods had good coherence. The measurement described is simple and reliable, and may be served as a new method for noninvasively and continuously measurement of blood <span class="hlt">pressure</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APS..APRX13004M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APS..APRX13004M"><span>Using Clifford Algebra to Understand the Nature of Negative <span class="hlt">Pressure</span> <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McClellan, Gene</p> <p>2014-03-01</p> <p>The geometric algebra of 3-D Euclidean space, a sub-discipline of Clifford algebra, is a useful tool for analyzing <span class="hlt">wave</span> propagation. We use geometric algebra to explore the concept of negative <span class="hlt">pressure</span>. In free space a straightforward extension of Maxwell's equations using geometric algebra yields a theory in which classical electromagnetic <span class="hlt">waves</span> coexist with nonelectromagnetic <span class="hlt">waves</span> having retrograde momentum. By retrograde momentum we mean <span class="hlt">waves</span> carrying momentum pointing in the opposite direction of energy flow. If such <span class="hlt">waves</span> exist, they would have negative <span class="hlt">pressure</span>. In rebounding from a wall, they would pull rather than push. In this presentation we use standard methods of analyzing energy and momentum conservation and their flow through the surface of an enclosed volume to illustrate the properties of both the electromagnetic and nonelectromagnetic solutions of the extended Maxwell equations. The nonelectromagnetic <span class="hlt">waves</span> consist of coupled scalar and electric <span class="hlt">waves</span> and coupled magnetic and pseudoscalar <span class="hlt">waves</span>. They superimpose linearly with electromagnetic <span class="hlt">waves</span>. We show that the nonelectromagnetic <span class="hlt">waves</span>, besides having negative <span class="hlt">pressure</span>, propagate with the speed of light and do not interact with conserved electric currents. Hence, they have three properties in common with dark energy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SSCom.263...23K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SSCom.263...23K"><span><span class="hlt">Pressure-induced</span> metallization in Erbium trihydride</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kuzovnikov, M. A.; Eremets, M. I.; Drozdov, A. P.; Tkacz, M.</p> <p>2017-09-01</p> <p>Electrical resistivity and Raman spectra of ErH3 were studied in a diamond anvil cell under high <span class="hlt">pressure</span> up to 140 GPa in the temperature range 4-300 K. A crossover from a semiconductor-like to a metallic temperature dependence of resistivity at fixed <span class="hlt">pressures</span> was observed at about 50 GPa. In the <span class="hlt">pressure</span> range 80-140 GPa a resistivity maximum was observed at the R(T) dependencies. The temperature corresponding to this maximum linearly increased with <span class="hlt">pressure</span> increase, reaching 26 K at 140 GPa. No superconductivity was observed in the studied <span class="hlt">pressure</span>-temperature range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DMP.T8002C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DMP.T8002C"><span>Quench-<span class="hlt">induced</span> correlation <span class="hlt">waves</span>, and quantum grenades</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Corson, John; Bohn, John</p> <p>2016-05-01</p> <p>We investigate the <span class="hlt">wave</span> packet dynamics of a pair of particles that undergoes a rapid change of scattering length. Such quenches have recently become experimentally feasible with fast magnetic-field ramps and optical switching in the vicinity of a Feshbach resonance. The short-range interactions are modelled in the zero-range limit, where the quench is accomplished by switching the boundary condition of the <span class="hlt">wave</span> function at vanishing particle separation. This generates a correlation <span class="hlt">wave</span> that propagates rapidly to nonzero particle separations. We have derived universal, analytic results for this process that lead to a simple phase-space picture of quench-<span class="hlt">induced</span> scattering. Intuitively, the strength of the correlation <span class="hlt">wave</span> relates to the initial contact of the system. A natural consequence is that the <span class="hlt">waves</span> are significant when the quench dissociates, at least partially, a bound state. These <span class="hlt">waves</span> can propagate with high energy from one lattice site to another, potentially triggering highly non-equilibrium dynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/240871','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/240871"><span>Biological effects of laser-<span class="hlt">induced</span> stress <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Doukas, A.; Lee, S.; McAuliffe, D.</p> <p>1995-12-31</p> <p>Laser-<span class="hlt">induced</span> stress <span class="hlt">waves</span> can be generated by one of the following mechanisms: Optical breakdown, ablation or rapid heating of an absorbing medium. These three modes of laser interaction with matter allow the investigation of cellular and tissue responses to stress <span class="hlt">waves</span> with different characteristics and under different conditions. The most widely studied phenomena are those of the collateral damage seen in photodisruption in the eye and in 193 run ablation of cornea and skin. On the other hand, the therapeutic application of laser-<span class="hlt">induced</span> stress <span class="hlt">waves</span> has been limited to the disruption of noncellular material such as renal stones, atheromatous plaque and vitreous strands. The effects of stress <span class="hlt">waves</span> to cells and tissues can be quite disparate. Stress <span class="hlt">waves</span> can fracture tissue, damage cells, and increase the permeability of the plasma membrane. The viability of cell cultures exposed to stress <span class="hlt">waves</span> increases with the peak stress and the number of pulses applied. The rise time of the stress <span class="hlt">wave</span> also influences the degree of cell injury. In fact, cell viability, as measured by thymidine incorporation, correlates better with the stress gradient than peak stress. Recent studies have also established that stress <span class="hlt">waves</span> <span class="hlt">induce</span> a transient increase of the permeability of the plasma membrane in vitro. In addition, if the stress gradient is below the damage threshhold, the cells remain viable. Thus, stress <span class="hlt">waves</span> can be useful as a means of drug delivery, increasing the intracellular drug concentration and allowing the use of drugs which are impermeable to the cell membrane. The present studies show that it is important to create controllable stress <span class="hlt">waves</span>. The wavelength tunability and the micropulse structure of the free electron laser is ideal for generating stress <span class="hlt">waves</span> with independently adjustable parameters, such as rise time, duration and peak stress.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890034508&hterms=ruby+cell&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Druby%2Bcell','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890034508&hterms=ruby+cell&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Druby%2Bcell"><span>Elimination of <span class="hlt">pressure-induced</span> fluorescence in diamond anvils</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Eggert, Jon H.; Goettel, Kenneth A.; Silvera, Isaac F.</p> <p>1988-01-01</p> <p>At <span class="hlt">pressures</span> above one megabar (100 GPa) in high-<span class="hlt">pressure</span> diamond anvil cell experiments, the ruby fluorescence signal needed for <span class="hlt">pressure</span> calibration is increasingly difficult to measure. A primary cause of this difficulty is the presence of an intense <span class="hlt">pressure-induced</span> diamond fluorescence. A tentative identification of this <span class="hlt">pressure-induced</span> fluorescence is given, a technique for the elimination of this fluorescence is reported. It is demonstrated that weak ruby signals, completely hidden by diamond fluorescence, are now easily measured with this technique.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvL.117v7203O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvL.117v7203O"><span>Curvature-<span class="hlt">Induced</span> Asymmetric Spin-<span class="hlt">Wave</span> Dispersion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Otálora, Jorge A.; Yan, Ming; Schultheiss, Helmut; Hertel, Riccardo; Kákay, Attila</p> <p>2016-11-01</p> <p>In magnonics, spin <span class="hlt">waves</span> are conceived of as electron-charge-free information carriers. Their <span class="hlt">wave</span> behavior has established them as the key elements to achieve low power consumption, fast operative rates, and good packaging in magnon-based computational technologies. Hence, knowing alternative ways that reveal certain properties of their undulatory motion is an important task. Here, we show using micromagnetic simulations and analytical calculations that spin-<span class="hlt">wave</span> propagation in ferromagnetic nanotubes is fundamentally different than in thin films. The dispersion relation is asymmetric regarding the sign of the <span class="hlt">wave</span> vector. It is a purely curvature-<span class="hlt">induced</span> effect and its fundamental origin is identified to be the classical dipole-dipole interaction. The analytical expression of the dispersion relation has the same mathematical form as in thin films with the Dzyalonshiinsky-Moriya interaction. Therefore, this curvature-<span class="hlt">induced</span> effect can be seen as a "dipole-<span class="hlt">induced</span> Dzyalonshiinsky-Moriya-like" effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930039066&hterms=wave+flat&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwave%2Bflat','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930039066&hterms=wave+flat&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwave%2Bflat"><span>Wall <span class="hlt">pressure</span> fluctuations beneath swept shock <span class="hlt">wave</span>/boundary layer interactions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Garg, S.; Settles, G. S.</p> <p>1993-01-01</p> <p>An experimental research program providing basic knowledge and establishing a database on the fluctuating <span class="hlt">pressure</span> loads produced on aerodynamic surfaces beneath 3D shock <span class="hlt">wave</span>/boundary layer interactions is presented. A turbulent boundary layer on a flat plate is subjected to interactions with swept planar shock <span class="hlt">waves</span> generated by sharp fins at angle of attack. Measurements are made for the first time in the aft areas of these interactions, showing fluctuating <span class="hlt">pressure</span> levels as high as 160 dB.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19720046009&hterms=alkali+metals&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dalkali%2Bmetals','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19720046009&hterms=alkali+metals&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dalkali%2Bmetals"><span>Theoretical calculation of plane <span class="hlt">wave</span> speeds for alkali metals under <span class="hlt">pressure</span>.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Eftis, J.; Macdonald, D. E.; Arkilic, G. M.</p> <p>1971-01-01</p> <p>Theoretical calculations of the variation with <span class="hlt">pressure</span> of small amplitude plane <span class="hlt">wave</span> speeds are performed for sodium and potassium at zero temperature. The results obtained for <span class="hlt">wave</span> speeds associated with volume dependent second-order elastic coefficients show better agreement with experimental data than for <span class="hlt">wave</span> speeds associated with shear dependent coefficients. This result is believed to be due to omission of the band structure correction to the strain energy density.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24341042','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24341042"><span>[Intracranial <span class="hlt">pressure</span> plateau <span class="hlt">waves</span> in patients with severe traumatic brain injury].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Oshorov, A V; Savin, I A; Goriachev, A S; Popugaev, K A; Polupan, A A; Sychev, A A; Gavrilov, A G; Kravchuk, A D; Zakharova, N E; Danilov, G V; Potapov, A A</p> <p>2013-01-01</p> <p>The goal of the study was to assess frequency of plato <span class="hlt">waves</span>, their influence on outcomes and define factors leading to plato <span class="hlt">waves</span>. Ninety eight patients with severe traumatic brain injury (TBI) were included. Blood <span class="hlt">pressure</span> (BP), intracranial <span class="hlt">pressure</span> (ICP), cerebral perfusion <span class="hlt">pressure</span> (CPP) and <span class="hlt">pressure</span> reactivity index (Prx) were registered. Age was 34 +/- 13.6. There were 73 male and 25 female. Glasgow Coma Scale (GCS) was 6 +/- 1.4. Plato <span class="hlt">waves</span> developed in 24 patients (group 1), 74 patients (group 2) did not have plato <span class="hlt">waves</span>. Median of plato <span class="hlt">waves</span> in the 1st group was 7[3.5; 7]. They developed on 3rd [2;4.5] day. Maximum level of ICP during plato <span class="hlt">waves</span> was 47.5 [40;53] mmHg, its duration was 8.5 [7;27] minutes. In the group 1 Prx was significantly lower during first day, than in the group 2. Duration of ICP monitoring was longer in the group I due to presence of plato <span class="hlt">waves</span> in these patients. CPP did not differ in groups, because CPP was strictly controlled. Patients of the group I had preserved autoregulation and less severe trauma (predominance of closed trauma and Marshall I, II type of brain damage). Plato <span class="hlt">waves</span> did not predict bad outcomes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20731389','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20731389"><span><span class="hlt">Pressure-induced</span> decomposition of indium hydroxide.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gurlo, Aleksander; Dzivenko, Dmytro; Andrade, Miria; Riedel, Ralf; Lauterbach, Stefan; Kleebe, Hans-Joachim</p> <p>2010-09-15</p> <p>A static <span class="hlt">pressure-induced</span> decomposition of indium hydroxide into metallic indium that takes place at ambient temperature is reported. The lattice parameter of c-In(OH)(3) decreased upon compression from 7.977(2) to approximately 7.45 A at 34 GPa, corresponding to a decrease in specific volume of approximately 18%. Fitting the second-order Birch-Murnaghan equation of state to the obtained compression data gave a bulk modulus of 99 +/- 3 GPa for c-In(OH)(3). The c-In(OH)(3) crystals with a size of approximately 100 nm are comminuted upon compression, as indicated by the grain-size reduction reflected in broadening of the diffraction reflections and the appearance of smaller (approximately 5 nm) incoherently oriented domains in TEM. The rapid decompression of compressed c-In(OH)(3) leads to partial decomposition of indium hydroxide into metallic indium, mainly as a result of localized stress gradients caused by relaxation of the highly disordered indium sublattice in indium hydroxide. This partial decomposition of indium hydroxide into metallic indium is irreversible, as confirmed by angle-dispersive X-ray diffraction, transmission electron microscopy imaging, Raman scattering, and FTIR spectroscopy. Recovered c-In(OH)(3) samples become completely black and nontransparent and show typical features of metals, i.e., a falling absorption in the 100-250 cm(-1) region accompanied by a featureless spectrum in the 250-2500 cm(-1) region in the Raman spectrum and Drude-like absorption of free electrons in the region of 4000-8000 cm(-1) in the FTIR spectrum. These features were not observed in the initial c-In(OH)(3), which is a typical white wide-band-gap semiconductor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6278791','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6278791"><span>Quantification of abnormal intracranial <span class="hlt">pressure</span> <span class="hlt">waves</span> and isotope cisternography for diagnosis of occult communicating hydrocephalus</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cardoso, E.R.; Piatek, D.; Del Bigio, M.R.; Stambrook, M.; Sutherland, J.B.</p> <p>1989-01-01</p> <p>Nineteen consecutive patients with suspected occult communicating hydrocephalus were investigated by means of clinical evaluation, neuropsychological testing, isotope cisternography, computed tomography scanning, and continuous intracranial <span class="hlt">pressure</span> monitoring. Semi-quantitative grading systems were used in the evaluation of the clinical, neuropsychological, and cisternographic assessments. Clinical examination, neuropsychological testing, and computed tomography scanning were repeated 3 months after ventriculoperitoneal shunting. All patients showed abnormal intracranial <span class="hlt">pressure</span> <span class="hlt">waves</span> and all improved after shunting. There was close correlation between number, peak, and pulse <span class="hlt">pressures</span> of B <span class="hlt">waves</span> and the mean intracranial <span class="hlt">pressure</span>. However, quantification of B <span class="hlt">waves</span> by means of number, frequency, and amplitude did not help in predicting the degree of clinical improvement postshunting. The most sensitive predictor of favorable response to shunting was enlargement of the temporal horns on computed tomography scan. Furthermore, the size of temporal horns correlated with mean intracranial <span class="hlt">pressure</span>. There was no correlation between abnormalities on isotope cisternography and clinical improvement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930036960&hterms=WENG&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DWENG','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930036960&hterms=WENG&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DWENG"><span>Observations of height-dependent <span class="hlt">pressure</span>-perturbation structure of a strong mesoscale gravity <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Starr, David O'C.; Korb, C. L.; Schwemmer, Geary K.; Weng, Chi Y.</p> <p>1992-01-01</p> <p>Airborne observations using a downward-looking, dual-frequency, near-infrared, differential absorption lidar system provide the first measurements of the height-dependent <span class="hlt">pressure</span>-perturbation field associated with a strong mesoscale gravity <span class="hlt">wave</span>. A <span class="hlt">pressure</span>-perturbation amplitude of 3.5 mb was measured within the lowest 1.6 km of the atmosphere over a 52-km flight line. Corresponding vertical displacements of 250-500 m were inferred from lidar-observed displacement of aerosol layers. Accounting for probable <span class="hlt">wave</span> orientation, a horizontal wavelength of about 40 km was estimated. Satellite observations reveal <span class="hlt">wave</span> structure of a comparable scale in concurrent cirrus cloud fields over an extended area. Smaller-scale <span class="hlt">waves</span> were also observed. Local meteorological soundings are analyzed to confirm the existence of a suitable <span class="hlt">wave</span> duct. Potential <span class="hlt">wave</span>-generation mechanisms are examined and discussed. The large <span class="hlt">pressure</span>-perturbation <span class="hlt">wave</span> is attributed to rapid amplification or possible <span class="hlt">wave</span> breaking of a gravity <span class="hlt">wave</span> as it propagated offshore and interacted with a very stable marine boundary layer capped by a strong shear layer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/7024405','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/7024405"><span>Liquifaction of fluid saturated rocks due to explosion-<span class="hlt">induced</span> stress <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dey, T.N.; Brown, J.A.</p> <p>1990-01-01</p> <p>Shock-<span class="hlt">induced</span> liquefaction of a water-saturated rock may occur during the passage of a large amplitude stress <span class="hlt">wave</span>, such as that due to an explosive. We studied this phenomena numerically with the aid of a material model which incorporates effective stress principles, and experimentally with a gas gun. Our numerical model is capable of calculating material response for both small and large deformation and any initial saturation. Phase transitions of the solid phase and the water phase are also allowed. Fitting the model to dry gas gun experiments allowed reasonable predictions of nearly saturated experiments. Liquefaction, the loss of shear strength when pore <span class="hlt">pressure</span> exceeds the mean stress, appears to occur during the unloading portion of these experiments. The pore crushing which occurs, even under fully saturated conditions, leads to greater attenuation of a stress <span class="hlt">wave</span>, as well as liquefaction of the rock and a lengthening of the <span class="hlt">wave</span> duration, as the <span class="hlt">wave</span> passes. 12 refs., 4 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvF...2i4701H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvF...2i4701H"><span><span class="hlt">Wave-induced</span> vortex recoil and nonlinear refraction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Humbert, Thomas; Aumaître, Sébastien; Gallet, Basile</p> <p>2017-09-01</p> <p>When a vortex refracts surface <span class="hlt">waves</span>, the momentum flux carried by the <span class="hlt">waves</span> changes direction and the <span class="hlt">waves</span> <span class="hlt">induce</span> a reaction force on the vortex. We study experimentally the resulting vortex distortion. Incoming surface gravity <span class="hlt">waves</span> impinge on a steady vortex of velocity U0 driven magnetohydrodynamically at the bottom of a fluid layer. The <span class="hlt">waves</span> <span class="hlt">induce</span> a shift of the vortex center in the direction transverse to <span class="hlt">wave</span> propagation, together with a decrease in surface vorticity. We interpret these two phenomena in the framework introduced by Craik and Leibovich [A. D. D. Craik and S. Leibovich, J. Fluid Mech. 73, 401 (1976), 10.1017/S0022112076001420]: We identify the dimensionless Stokes drift S =Us/U0 as the relevant control parameter, Us being the Stokes drift velocity of the <span class="hlt">waves</span>. We propose a simple vortex line model that indicates that the shift of the vortex center originates from a balance between vorticity advection by the Stokes drift and self-advection of the vortex. The decrease in surface vorticity is interpreted as a consequence of vorticity expulsion by the fast Stokes drift, which confines it at depth. This purely hydrodynamic process is analogous to the magnetohydrodynamic expulsion of a magnetic field by a rapidly moving conductor through the electromagnetic skin effect. We study vorticity expulsion in the limit of fast Stokes drift and deduce that the surface vorticity decreases as 1 /S , a prediction that is compatible with the experimental data. Such <span class="hlt">wave-induced</span> vortex distortions have important consequences for the nonlinear regime of <span class="hlt">wave</span> refraction: The refraction angle rapidly decreases with <span class="hlt">wave</span> intensity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..94u4509P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..94u4509P"><span>Skyrmion-<span class="hlt">induced</span> bound states in a p -<span class="hlt">wave</span> superconductor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pöyhönen, Kim; Westström, Alex; Pershoguba, Sergey S.; Ojanen, Teemu; Balatsky, Alexander V.</p> <p>2016-12-01</p> <p>In s -<span class="hlt">wave</span> systems, it has been theoretically shown that a ferromagnetic film hosting a skyrmion can <span class="hlt">induce</span> a bound state embedded in the opposite-spin continuum. In this work, we consider a case of skyrmion-<span class="hlt">induced</span> state in a p -<span class="hlt">wave</span> superconductor. We find that the skyrmion <span class="hlt">induces</span> a bound state that generally resides within the spectral gap and is isolated from all other states, in contrast to the case of conventional superconductors. To this end, we derive an approximate expression for the T matrix, through which we calculate the spin-polarized local density of states which is observable in scanning tunneling microscopy measurements. We find the unique spectroscopic features of the skyrmion-<span class="hlt">induced</span> bound state and discuss how our predictions could be employed as experimental probes for p -<span class="hlt">wave</span> superconducting states.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27078302','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27078302"><span>Nonequilibrium fluctuation-<span class="hlt">induced</span> Casimir <span class="hlt">pressures</span> in liquid mixtures.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kirkpatrick, T R; Ortiz de Zárate, J M; Sengers, J V</p> <p>2016-03-01</p> <p>In this article we derive expressions for Casimir-like <span class="hlt">pressures</span> <span class="hlt">induced</span> by nonequilibrium concentration fluctuations in liquid mixtures. The results are then applied to liquid mixtures in which the concentration gradient results from a temperature gradient through the Soret effect. A comparison is made between the <span class="hlt">pressures</span> <span class="hlt">induced</span> by nonequilibrium concentration fluctuations in liquid mixtures and those <span class="hlt">induced</span> by nonequilibrium temperature fluctuations in one-component fluids. Some suggestions for experimental verification procedures are also presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950015988','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950015988"><span><span class="hlt">Wave</span> Journal Bearing. Part 2: Experimental <span class="hlt">Pressure</span> Measurements and Fractional Frequency Whirl Threshold for <span class="hlt">Wave</span> and Plain Journal Bearings</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Walker, James F.; Dimofte, Florin; Addy, Harold E., Jr.</p> <p>1995-01-01</p> <p>A new hydrodynamic bearing concept, the <span class="hlt">wave</span> journal bearing, is being developed because it has better stability characteristics than plain journal bearings while maintaining similar load capacity. An analysis code to predict the steady state and dynamic performance of the <span class="hlt">wave</span> journal bearing is also part of the development. To verify numerical predictions and contrast the <span class="hlt">wave</span> journal bearing's stability characteristics to a plain journal bearing, tests were conducted at NASA Lewis Research Center using an air bearing test rig. Bearing film <span class="hlt">pressures</span> were measured at 16 ports located around the bearing circumference at the middle of the bearing length. The <span class="hlt">pressure</span> measurements for both a plain journal bearing and a <span class="hlt">wave</span> journal bearing compared favorably with numerical predictions. Both bearings were tested with no radial load to determine the speed threshold for self-excited fractional frequency whirl. The plain journal bearing started to whirl immediately upon shaft start-up. The <span class="hlt">wave</span> journal did not incur self-excited whirl until 800 to 900 rpm as predicted by the analysis. Furthermore, the <span class="hlt">wave</span> bearing's geometry limited the whirl orbit to less than the bearing's clearance. In contrast, the plain journal bearing did not limit the whirl orbit, causing it to rub.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20779181','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20779181"><span>Molecular-level mechanisms of nanoparticle detachment in laser-<span class="hlt">induced</span> plasma shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zhou Dong; Cetinkaya, Cetin</p> <p>2006-04-24</p> <p>Detachment and detachment mechanisms of nanoparticles from flat surfaces subjected to shock <span class="hlt">waves</span> are investigated by employing molecular gas dynamic simulations using the direct simulation Monte Carlo method and experimental transient <span class="hlt">pressure</span> data. Two mechanisms for nanoparticle detachment based on rolling moment resistance of the adhesion bond and the elastic restitution effect are introduced. As a result of present simulations, it is computationally demonstrated that the pulsed laser-<span class="hlt">induced</span> shock <span class="hlt">waves</span> can generate sufficient rolling moments to detach sub-100-nm particles and initiate removal. The transient moment exerted on a 60 nm polystyrene latex particle on a silicon substrate is presented and discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006ApPhL..88q3109Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006ApPhL..88q3109Z"><span>Molecular-level mechanisms of nanoparticle detachment in laser-<span class="hlt">induced</span> plasma shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhou, Dong; Cetinkaya, Cetin</p> <p>2006-04-01</p> <p>Detachment and detachment mechanisms of nanoparticles from flat surfaces subjected to shock <span class="hlt">waves</span> are investigated by employing molecular gas dynamic simulations using the direct simulation Monte Carlo method and experimental transient <span class="hlt">pressure</span> data. Two mechanisms for nanoparticle detachment based on rolling moment resistance of the adhesion bond and the elastic restitution effect are introduced. As a result of present simulations, it is computationally demonstrated that the pulsed laser-<span class="hlt">induced</span> shock <span class="hlt">waves</span> can generate sufficient rolling moments to detach sub-100-nm particles and initiate removal. The transient moment exerted on a 60nm polystyrene latex particle on a silicon substrate is presented and discussed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70014435','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70014435"><span>On seismically <span class="hlt">induced</span> pore <span class="hlt">pressure</span> and settlement</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Chen, Albert T.F.</p> <p>1988-01-01</p> <p>Two different approaches are used to estimate pore <span class="hlt">pressures</span> and settlement in a 50-ft (15.2-m) sand deposit subjected to a variety of earthquake loadings. Although the two approaches seem consistent in predicting the occurrence of liquefaction, the results show that they are quite divergent in estimating pore-<span class="hlt">pressure</span> build-ups and magnitude of ground settlement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017OcMod.116..118R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017OcMod.116..118R"><span>Efficient non-hydrostatic modelling of 3D <span class="hlt">wave-induced</span> currents using a subgrid approach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rijnsdorp, Dirk P.; Smit, Pieter B.; Zijlema, Marcel; Reniers, Ad J. H. M.</p> <p>2017-08-01</p> <p><span class="hlt">Wave-induced</span> currents are an ubiquitous feature in coastal waters that can spread material over the surf zone and the inner shelf. These currents are typically under resolved in non-hydrostatic <span class="hlt">wave</span>-flow models due to computational constraints. Specifically, the low vertical resolutions adequate to describe the <span class="hlt">wave</span> dynamics - and required to feasibly compute at the scales of a field site - are too coarse to account for the relevant details of the three-dimensional (3D) flow field. To describe the relevant dynamics of both <span class="hlt">wave</span> and currents, while retaining a model framework that can be applied at field scales, we propose a two grid approach to solve the governing equations. With this approach, the vertical accelerations and non-hydrostatic <span class="hlt">pressures</span> are resolved on a relatively coarse vertical grid (which is sufficient to accurately resolve the <span class="hlt">wave</span> dynamics), whereas the horizontal velocities and turbulent stresses are resolved on a much finer subgrid (of which the resolution is dictated by the vertical scale of the mean flows). This approach ensures that the discrete <span class="hlt">pressure</span> Poisson equation - the solution of which dominates the computational effort - is evaluated on the coarse grid scale, thereby greatly improving efficiency, while providing a fine vertical resolution to resolve the vertical variation of the mean flow. This work presents the general methodology, and discusses the numerical implementation in the SWASH <span class="hlt">wave</span>-flow model. Model predictions are compared with observations of three flume experiments to demonstrate that the subgrid approach captures both the nearshore evolution of the <span class="hlt">waves</span>, and the <span class="hlt">wave-induced</span> flows like the undertow profile and longshore current. The accuracy of the subgrid predictions is comparable to fully resolved 3D simulations - but at much reduced computational costs. The findings of this work thereby demonstrate that the subgrid approach has the potential to make 3D non-hydrostatic simulations feasible at the scale of a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.2410L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.2410L"><span><span class="hlt">Wave-induced</span> current considering <span class="hlt">wave</span>-tide interaction in Haeundae</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lim, Hak Soo</p> <p>2017-04-01</p> <p>The Haeundae, located at the south eastern end of the Korean Peninsula, is a famous beach, which has an approximately 1.6 km long and 70 m wide coastline. The beach has been repeatedly eroded by the swell <span class="hlt">waves</span> caused by typhoons in summer and high <span class="hlt">waves</span> originating in the East Sea in winter. The Korean government conducted beach restoration projects including beach nourishment (620,000 m3) and construction of two submerged breakwaters near both ends of the beach. To prevent the beach erosion and to support the beach restoration project, the Korean government initiated a R&D project, the development of coastal erosion control technology since 2013. As a part of the project, we have been measuring <span class="hlt">waves</span> and currents at a water depth of 22 m, 1.8 km away from the beach using an acoustic <span class="hlt">wave</span> and current meter (AWAC) continuously for more than three years; we have also measured <span class="hlt">waves</span> and currents intensively near the surf-zone in summer and winter. In this study, a numerical simulation using a <span class="hlt">wave</span> and current coupled model (ROMS-SWAN) was conducted for determining the <span class="hlt">wave-induced</span> current considering seasonal swell <span class="hlt">waves</span> (Hs : 2.5 m, Tp: 12 s) and for better understanding of the coastal process near the surf-zone in Haeundae. By comparing the measured and simulated results, we found that cross-shore current during summer is mainly caused by the eddy produced by the <span class="hlt">wave-induced</span> current near the beach, which in turn, is generated by the strong <span class="hlt">waves</span> coming from the SSW and S directions. During other seasons, longshore <span class="hlt">wave-induced</span> current is produced by the swell <span class="hlt">waves</span> coming from the E and ESE directions. The longshore current heading west toward Dong-Back Island, west end of the beach, during all the seasons and eddy current toward Mipo-Port, east end of the beach, in summer which is well matched with the observed residual current. The <span class="hlt">wave-induced</span> current with long-term measurement data is incorporated in simulation of sediment transport modeling for developing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015shw1.conf..489N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015shw1.conf..489N"><span>Ultrafast Time Response <span class="hlt">Pressure</span>-Sensitive Paint for Unsteady Shock-<span class="hlt">Wave</span> Research</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Numata, Daiju; Asai, Keisuke</p> <p></p> <p><span class="hlt">Pressure</span>-Sensitive Paint (PSP) is an optical <span class="hlt">pressure</span> measurement technique widely used in aerodynamic experiments, and has been applied to unsteady shock-<span class="hlt">wave</span> phenomena [1, 2]. However, one of the largest problems to apply PSP to high-speed and unsteady phenomena is the response time of PSP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27003814','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27003814"><span>Pharmacologic Management of <span class="hlt">Pressure-Induced</span> Stromal Keratopathy after LASIK.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Unlu, Metin; Hondur, Ahmet M; Korkmaz, Safak; Kumova, Deniz; Yuksel, Erdem</p> <p>2016-07-01</p> <p>To emphasize the importance of anticipation of <span class="hlt">pressure-induced</span> stromal keratopathy (PISK) in eyes with a previous history of LASIK. A 40-year-old man developed LASIK-related <span class="hlt">pressure-induced</span> stromal keratopathy after uneventful phacoemulsification (Phaco) and intraocular lens (IOL) implantation in his left eye. With immediate discontinuation of the steroid drops and initiation of antiglaucoma medication, his visual acuity, interface edema, and haze improved rapidly. One year later, during Phaco with IOL implantation in his other eye, with anticipation of a similar LASIK-related <span class="hlt">pressure-induced</span> stromal keratopathy, a very brief course of soft steroid therapy was given together with antiglaucoma medication. Intraocular <span class="hlt">pressure</span> elevation was avoided, and no interface edema or haze was observed. This case illustrates that the risk for LASIK-related <span class="hlt">pressure-induced</span> stromal keratopathy may be reduced with appropriate precautions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14986410','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14986410"><span><span class="hlt">Pressure</span> <span class="hlt">wave</span> propagation in fluid-filled co-axial elastic tubes. Part 1: Basic theory.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Berkouk, K; Carpenter, P W; Lucey, A D</p> <p>2003-12-01</p> <p>Our work is motivated by ideas about the pathogenesis of syringomyelia. This is a serious disease characterized by the appearance of longitudinal cavities within the spinal cord. Its causes are unknown, but <span class="hlt">pressure</span> propagation is probably implicated. We have developed an inviscid theory for the propagation of <span class="hlt">pressure</span> <span class="hlt">waves</span> in co-axial, fluid-filled, elastic tubes. This is intended as a simple model of the intraspinal cerebrospinal-fluid system. Our approach is based on the classic theory for the propagation of longitudinal <span class="hlt">waves</span> in single, fluid-filled, elastic tubes. We show that for small-amplitude <span class="hlt">waves</span> the governing equations reduce to the classic <span class="hlt">wave</span> equation. The <span class="hlt">wave</span> speed is found to be a strong function of the ratio of the tubes' cross-sectional areas. It is found that the leading edge of a transmural <span class="hlt">pressure</span> pulse tends to generate compressive <span class="hlt">waves</span> with converging <span class="hlt">wave</span> fronts. Consequently, the leading edge of the <span class="hlt">pressure</span> pulse steepens to form a shock-like elastic jump. A weakly nonlinear theory is developed for such an elastic jump.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRD..118.4476L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRD..118.4476L"><span>Solar wind dynamic <span class="hlt">pressure</span> effect on planetary <span class="hlt">wave</span> propagation and synoptic-scale Rossby <span class="hlt">wave</span> breaking</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lu, Hua; Franzke, Christian; Martius, Olivia; Jarvis, Martin J.; Phillips, Tony</p> <p>2013-05-01</p> <p>We provide statistical evidence of the effect of the solar wind dynamic <span class="hlt">pressure</span> (Psw) on the northern winter and spring circulations. We find that the vertical structure of the Northern Annular Mode (NAM), the zonal mean circulation, and Eliassen-Palm (EP)-flux anomalies show a dynamically consistent pattern of downward propagation over a period of ~45 days in response to positive Psw anomalies. When the solar irradiance is high, the signature of Psw is marked by a positive NAM anomaly descending from the stratosphere to the surface during winter. When the solar irradiance is low, the Psw signal has the opposite sign, occurs in spring, and is confined to the stratosphere. The negative Psw signal in the NAM under low solar irradiance conditions is primarily governed by enhanced vertical EP-flux divergence and a warmer polar region. The winter Psw signal under high solar irradiance conditions is associated with positive anomalies of the horizontal EP-flux divergence at 55°N-75°N and negative anomalies at 25°N-45°N, which corresponds to the positive NAM anomaly. The EP-flux divergence anomalies occur ~15 days ahead of the mean-flow changes. A significant equatorward shift of synoptic-scale Rossby <span class="hlt">wave</span> breaking (RWB) near the tropopause is detected during January-March, corresponding to increased anticyclonic RWB and a decrease in cyclonic RWB. We suggest that the barotropic instability associated with asymmetric ozone in the upper stratosphere and the baroclinic instability associated with the polar vortex in the middle and lower stratosphere play a critical role for the winter signal and its downward propagation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15812285','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15812285"><span>Acetabular augmentation <span class="hlt">induced</span> by extracorporeal shock <span class="hlt">waves</span> in rabbits.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Saisu, Takashi; Kamegaya, Makoto; Wada, Yuichi; Takahashi, Kenji; Mitsuhashi, Shigeru; Moriya, Hideshige; Maier, Markus</p> <p>2005-05-01</p> <p>We conducted this animal study to demonstrate whether exposing the acetabulum in immature rabbits to extracorporeal shock <span class="hlt">waves</span> <span class="hlt">induces</span> bone formation in the acetabulum. Five thousand shock <span class="hlt">waves</span> of 100 MPa each were directed, from outside, at the acetabular roof of eight immature rabbits. At each of two time points (4 and 8 weeks) after treatment, the pelvises of four rabbits were removed and evaluated morphologically. Woven bone formation was observed on the lateral margin of the acetabular roof at 4 weeks after treatment, and the breadth of the acetabular roof in the coronal plane was significantly increased. Eight weeks after treatment, the woven bone disappeared; the breadth of the acetabular roof, however, was significantly increased. These findings demonstrated that extracorporeal shock <span class="hlt">waves</span> <span class="hlt">induced</span> acetabular augmentation in rabbits. We conclude that extracorporeal shock <span class="hlt">waves</span>, perhaps, could be applied clinically for the treatment of acetabular dysplasia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AIPC.1060..106P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AIPC.1060..106P"><span>Two Dimensional Finite Element Analysis for the Effect of a <span class="hlt">Pressure</span> <span class="hlt">Wave</span> in the Human Brain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ponce L., Ernesto; Ponce S., Daniel</p> <p>2008-11-01</p> <p>Brain injuries in people of all ages is a serious, world-wide health problem, with consequences as varied as attention or memory deficits, difficulties in problem-solving, aggressive social behavior, and neuro degenerative diseases such as Alzheimer's and Parkinson's. Brain injuries can be the result of a direct impact, but also <span class="hlt">pressure</span> <span class="hlt">waves</span> and direct impulses. The aim of this work is to develop a predictive method to calculate the stress generated in the human brain by <span class="hlt">pressure</span> <span class="hlt">waves</span> such as high power sounds. The finite element method is used, combined with elastic <span class="hlt">wave</span> theory. The predictions of the generated stress levels are compared with the resistance of the arterioles that pervade the brain. The problem was focused to the Chilean mining where there are some accidents happen by detonations and high sound level. There are not formal medical investigation, however these <span class="hlt">pressure</span> <span class="hlt">waves</span> could produce human brain damage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1981AdSpR...1..103J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1981AdSpR...1..103J"><span>Xe/+/ -<span class="hlt">induced</span> ion-cyclotron harmonic <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jones, D.</p> <p></p> <p>Xenon ion sources on an ejectable package separated from the main payload during the flights of Porcupine rockets F3 and F4 which were launched from Kiruna, Sweden on March 19 and 31, 1979, respectively. The effects of the xenon ion beam, detected by the LF (f less than 16 kHz) wideband electric field experiment and analyzed by using a sonograph, are discussed. Particular attention is given to the stimulation of the ion-cyclotron harmonic <span class="hlt">waves</span> which are usually linked to the local proton gyro-frequency, but are sometimes related to half that frequency. It was found that in a plasma dominated by O(+) ions, a small amount (1-10%) of protons could cause an effect such that the O(+) cyclotron harmonic <span class="hlt">waves</span> are set up by the hydrogen ions, the net result being the observation of harmonic emissions separated by the hydrogen ion gyro frequency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24188310','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24188310"><span><span class="hlt">Pressure-induced</span> gelatinization of starch in excess water.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vallons, Katleen J R; Ryan, Liam A M; Arendt, Elke K</p> <p>2014-01-01</p> <p>High <span class="hlt">pressure</span> processing is a promising non-thermal technology for the development of fresh-like, shelf-stable foods. The effect of high <span class="hlt">pressure</span> on starch has been explored by many researchers using a wide range of techniques. In general, heat and <span class="hlt">pressure</span> have similar effects: if sufficiently high, they both <span class="hlt">induce</span> gelatinization of starch in excess water, resulting in a transition of the native granular structure to a starch paste or gel. However, there are significant differences in the structural and rheological properties between heated and <span class="hlt">pressurized</span> starches. These differences offer benefits with respect to new product development. However, in order to implement high-<span class="hlt">pressure</span> technology to starch and starch-containing products, a good understanding of the mechanism of <span class="hlt">pressure-induced</span> gelatinization is necessary. Studies that are published in this area are reviewed, and the similarities and differences between starches gelatinized by <span class="hlt">pressure</span> and by temperature are summarized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012Chaos..22c3132B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012Chaos..22c3132B"><span>Pacemaker interactions <span class="hlt">induce</span> reentrant <span class="hlt">wave</span> dynamics in engineered cardiac culture</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borek, Bartłomiej; Shajahan, T. K.; Gabriels, James; Hodge, Alex; Glass, Leon; Shrier, Alvin</p> <p>2012-09-01</p> <p>Pacemaker interactions can lead to complex <span class="hlt">wave</span> dynamics seen in certain types of cardiac arrhythmias. We use experimental and mathematical models of pacemakers in heterogeneous excitable media to investigate how pacemaker interactions can be a mechanism for <span class="hlt">wave</span> break and reentrant <span class="hlt">wave</span> dynamics. Embryonic chick ventricular cells are cultured invitro so as to create a dominant central pacemaker site that entrains other pacemakers in the medium. Exposure of those cultures to a potassium channel blocker, E-4031, leads to emergence of peripheral pacemakers that compete with each other and with the central pacemaker. <span class="hlt">Waves</span> emitted by faster pacemakers break up over the slower pacemaker to form reentrant <span class="hlt">waves</span>. Similar dynamics are observed in a modified FitzHugh-Nagumo model of heterogeneous excitable media with two distinct sites of pacemaking. These findings elucidate a mechanism of pacemaker-<span class="hlt">induced</span> reentry in excitable media.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApPhL.100m2411S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApPhL.100m2411S"><span>Attenuation of propagating spin <span class="hlt">wave</span> <span class="hlt">induced</span> by layered nanostructures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sekiguchi, K.; Vader, T. N.; Yamada, K.; Fukami, S.; Ishiwata, N.; Seo, S. M.; Lee, S. W.; Lee, K. J.; Ono, T.</p> <p>2012-03-01</p> <p>Spin <span class="hlt">wave</span> attenuation in the layered [FeNi/Pt]6/FeNi thin films was investigated by the time-domain electrical measurement. The spin-<span class="hlt">wave</span> waveform was detected with an asymmetric coplanar strip transmission line, as an <span class="hlt">induced</span> voltage flowing into a fast oscilloscope. We report that the amplitude of a spin-<span class="hlt">wave</span> packet was systematically changed by controlling the thickness of a platinum layer, up to a maximum change of 50%. The virtues of spin <span class="hlt">wave</span>, ultrafast propagation velocity and non-reciprocal emission, are preserved in this manner. This means that the Pt layer can manipulate an arbitral power-level of spin-<span class="hlt">wave</span> input signal (reliable attenuator).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6158932','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6158932"><span>Ion radial transport <span class="hlt">induced</span> by ICRF <span class="hlt">waves</span> in tokamaks</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Chen, L.; Vaclavik, J.; Hammett, G.W.</p> <p>1987-05-01</p> <p>The <span class="hlt">wave-induced</span> fluxes of energetic-trapped ions during ICRF heating of tokamak plasmas are calculated using quasilinear equations. A simple single particle model of this transport mechanism is also given. Both a convective flux proportional to k/sub phi/vertical bar E/sub +/vertical bar/sup 2/ and a diffusive flux proportional to k/sub phi//sup 2/vertical bar E/sub +/vertical bar/sup 2/ are found. Here, k/sub phi/ is the toroidal <span class="hlt">wave</span> number and E/sub +/ is the left-hand polarized <span class="hlt">wave</span> field. The convective flux may become significant for large k/sub phi/ if the <span class="hlt">wave</span> spectrum is asymmetric in k/sub phi/. But for the conditions of most previous experiments, these calculations indicate that radial transport driven directly by the ICRF <span class="hlt">wave</span> is unimportant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27951503','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27951503"><span>Effect of <span class="hlt">pressurization</span> on helical guided <span class="hlt">wave</span> energy velocity in fluid-filled pipes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dubuc, Brennan; Ebrahimkhanlou, Arvin; Salamone, Salvatore</p> <p>2017-03-01</p> <p>The effect of <span class="hlt">pressurization</span> stresses on helical guided <span class="hlt">waves</span> in a thin-walled fluid-filled pipe is studied by modeling leaky Lamb <span class="hlt">waves</span> in a stressed plate bordered by fluid. Fluid <span class="hlt">pressurization</span> produces hoop and longitudinal stresses in a thin-walled pipe, which corresponds to biaxial in-plane stress in a plate waveguide model. The effect of stress on guided <span class="hlt">wave</span> propagation is accounted for through nonlinear elasticity and finite deformation theory. Emphasis is placed on the stress dependence of the energy velocity of the guided <span class="hlt">wave</span> modes. For this purpose, an expression for the energy velocity of leaky Lamb <span class="hlt">waves</span> in a stressed plate is derived. Theoretical results are presented for the mode, frequency, and directional dependent variations in energy velocity with respect to stress. An experimental setup is designed for measuring variations in helical <span class="hlt">wave</span> energy velocity in a thin-walled water-filled steel pipe at different levels of <span class="hlt">pressure</span>. Good agreement is achieved between the experimental variations in energy velocity for the helical guided <span class="hlt">waves</span> and the theoretical leaky Lamb <span class="hlt">wave</span> solutions. Copyright © 2016 Elsevier B.V. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/580340','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/580340"><span>Alfv{acute e}n <span class="hlt">waves</span> and <span class="hlt">wave-induced</span> transport near an X point</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Myra, J.R.; DIppolito, D.A.</p> <p>1998-03-01</p> <p>The behavior of Alfv{acute e}n <span class="hlt">waves</span> and the corresponding variation of the <span class="hlt">wave-induced</span> transport coefficients along a field line including the divertor X-point region are examined. It is shown that several competing effects exist and can be quantified using a quasilinear diffusion model that takes the magnetic geometry of the X point into account. To address the issue of mode behavior and the validity of the eikonal approximation near the X point, an exact analytical solution of an equation describing Alfv{acute e}n <span class="hlt">waves</span> in the X-point region is obtained. The results suggest that the X-point region can only dominate Alfv{acute e}n <span class="hlt">wave-induced</span> transport on flux surfaces that are very close to the separatrix. {copyright} {ital 1998 American Institute of Physics.}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15014217','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15014217"><span>Amplification of <span class="hlt">Pressure</span> <span class="hlt">Waves</span> during Vibrational Equilibration of Excited Chemical Reaction Products</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tarver, C M</p> <p>2004-05-11</p> <p>The Non-Equilibrium Zeldovich - von Neumann - Doring (NEZND) theory of self-sustaining detonation identified amplification of <span class="hlt">pressure</span> wavelets during equilibration of vibrationally excited reaction products in the reaction zone as the physical mechanism by which exothermic chemical energy release sustains detonation <span class="hlt">waves</span>. This mechanism leads to the formation of the well-known, complex three-dimensional structure of a self-sustaining detonation <span class="hlt">wave</span>. This amplification mechanism is postulated to be a general property of subsonic and supersonic reactive flows occurring during: shock to detonation transition (SDT); hot spot ignition and growth; deflagration to detonation transition (DDT); flame acceleration by shock or compression <span class="hlt">waves</span>; and acoustic (sound) <span class="hlt">wave</span> amplification. The existing experimental and theoretical evidence for <span class="hlt">pressure</span> <span class="hlt">wave</span> amplification by chemical energy release into highly vibrationally excited product molecules under these reactive flow conditions is reviewed in this paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27573096','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27573096"><span>Transient <span class="hlt">pressure</span> <span class="hlt">wave</span> in the behind armor blunt trauma: experimental and computational investigation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Luo, Shaomin; Xu, Cheng; Wang, Shu; Wen, Yaoke</p> <p>2017-02-01</p> <p>In the last few decades, various researches focus on the transient <span class="hlt">pressure</span> in the behind armor blunt trauma. This paper presented a investigation on the transient <span class="hlt">pressure</span> in the ballistic gelatin behind a soft body armor subjected to the impacting from three ammunitions. Experimental results show that three peaks appear on the <span class="hlt">pressure</span>-time curves without taking into account the ammunition type and the impact velocity. Furthermore, numerical models of the test were created to compare modelling results to the <span class="hlt">pressure</span> from the <span class="hlt">pressure</span> gauges buried in the gelatin block. The main features on the <span class="hlt">pressure</span>-time cure were discussed to analyze the <span class="hlt">wave</span> formation and propagation. With the verified model, the effect of the boundary was also investigated to explain the <span class="hlt">wave</span> reflection which appeared after two peaks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19960014632','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19960014632"><span>High <span class="hlt">Pressure</span> Oxidizer Turbopump (HPOTP) <span class="hlt">inducer</span> dynamic design environment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Herda, D. A.; Gross, R. S.</p> <p>1995-01-01</p> <p>The dynamic environment must be known to evaluate high <span class="hlt">pressure</span> oxidizer turbopump <span class="hlt">inducer</span> fatigue life. This report sets the dynamic design loads for the alternate turbopump <span class="hlt">inducer</span> as determined by water-flow rig testing. Also, guidelines are given for estimating the dynamic environment for other <span class="hlt">inducer</span> and impeller applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26808146','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26808146"><span><span class="hlt">Pressure-induced</span> referred pain is expanded by persistent soreness.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Doménech-García, V; Palsson, T S; Herrero, P; Graven-Nielsen, T</p> <p>2016-05-01</p> <p>Several chronic pain conditions are accompanied with enlarged referred pain areas. This study investigated a novel method for assessing referred pain. In 20 healthy subjects, <span class="hlt">pressure</span> pain thresholds (PPTs) were recorded and <span class="hlt">pressure</span> stimuli (120% PPT) were applied bilaterally for 5 and 60 seconds at the infraspinatus muscle to <span class="hlt">induce</span> local and referred pain. Moreover, PPTs were measured bilaterally at the shoulder, neck, and leg before, during, and after hypertonic saline-<span class="hlt">induced</span> referred pain in the dominant infraspinatus muscle. The <span class="hlt">pressure</span> and saline-<span class="hlt">induced</span> pain areas were assessed on drawings. Subsequently, delayed onset muscle soreness was <span class="hlt">induced</span> using eccentric exercise of the dominant infraspinatus muscle. The day-1 assessments were repeated the following day (day 2). Suprathreshold <span class="hlt">pressure</span> stimulations and saline injections into the infraspinatus muscle caused referred pain to the frontal aspect of the shoulder/arm in all subjects. The 60-second <span class="hlt">pressure</span> stimulation caused larger referred pain areas compared with the 5-second stimulation (P < 0.01). Compared with <span class="hlt">pressure</span> stimulation, the saline-<span class="hlt">induced</span> referred pain area was larger (P < 0.02). After saline-<span class="hlt">induced</span> pain, the PPTs at the infraspinatus and supraspinatus muscles were reduced (P < 0.05), and the 5-second <span class="hlt">pressure-induced</span> referred pain area was larger than baseline. <span class="hlt">Pressure</span> pain thresholds at the infraspinatus and supraspinatus muscles were reduced at day 2 in the delayed onset muscle soreness side (P < 0.05). Compared with day 1, larger <span class="hlt">pressure</span> and saline-<span class="hlt">induced</span> referred pain areas were observed on day 2 (P < 0.05). Referred pain to the shoulder/arm was consistently <span class="hlt">induced</span> and enlarged after 1 day of muscle soreness, indicating that the referred pain area may be a sensitive biomarker for sensitization of the pain system.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24216739','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24216739"><span>Characterization of laser-driven shock <span class="hlt">waves</span> in solids using a fiber optic <span class="hlt">pressure</span> probe.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cranch, Geoffrey A; Lunsford, Robert; Grün, Jacob; Weaver, James; Compton, Steve; May, Mark; Kostinski, Natalie</p> <p>2013-11-10</p> <p>Measurement of laser-driven shock <span class="hlt">wave</span> <span class="hlt">pressure</span> in solid blocks of polymethyl methacrylate is demonstrated using fiber optic <span class="hlt">pressure</span> probes. Three probes based on a fiber Fabry-Perot, fiber Bragg grating, and interferometric fiber tip sensor are tested and compared. Shock <span class="hlt">waves</span> are generated using a high-power laser focused onto a thin foil target placed in close proximity to the test blocks. The fiber Fabry-Perot sensor appears capable of resolving the shock front with a rise time of 91 ns. The peak <span class="hlt">pressure</span> is estimated, using a separate shadowgraphy measurement, to be 3.4 GPa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993JaJAP..32.2487I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993JaJAP..32.2487I"><span>Variation of <span class="hlt">Pressure</span> Waveforms in Measurements of Extracorporeal Shock <span class="hlt">Wave</span> Lithotripter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Inose, Naoto; Ide, Masao</p> <p>1993-05-01</p> <p>In this paper, we describe measurement of variation in <span class="hlt">pressure</span> waveforms of the acoustic field of an extra-corporeal shock-<span class="hlt">wave</span> lithotripter (ESWL). Variations in the measured acoustic fields and <span class="hlt">pressure</span> waveform of an underwater spark-gap-type ESWL with an exhausted spark plug electrode have been reported by researchers using crystal sensors. If the ESWL spark plugs become exhausted, patients feel pain during kidney, biliary stone disintegration. We studied the relationship between exhaustion of electrodes and the variation of <span class="hlt">pressure</span> waveforms and shock-<span class="hlt">wave</span> fields of the ESWL using a newly developed hydrophone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1240062-characterization-laser-driven-shock-waves-solids-using-fiber-optic-pressure-probe','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1240062-characterization-laser-driven-shock-waves-solids-using-fiber-optic-pressure-probe"><span>Characterization of laser-driven shock <span class="hlt">waves</span> in solids using a fiber optic <span class="hlt">pressure</span> probe</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Cranch, Geoffrey A.; Lunsford, Robert; Grun, Jacob; ...</p> <p>2013-11-08</p> <p>Measurement of laser-driven shock <span class="hlt">wave</span> <span class="hlt">pressure</span> in solid blocks of polymethyl methacrylate is demonstrated using fiber optic <span class="hlt">pressure</span> probes. Three probes based on a fiber Fabry–Perot, fiber Bragg grating, and interferometric fiber tip sensor are tested and compared. Shock <span class="hlt">waves</span> are generated using a high-power laser focused onto a thin foil target placed in close proximity to the test blocks. The fiber Fabry–Perot sensor appears capable of resolving the shock front with a rise time of 91 ns. As a result, the peak <span class="hlt">pressure</span> is estimated, using a separate shadowgraphy measurement, to be 3.4 GPa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1175826','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1175826"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> swelling in microporous materials</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Vogt, Thomas; Hriljac, Joseph A.; Lee, Yongjae</p> <p>2006-07-11</p> <p>A method for capturing specified materials which includes contacting a microporous material with a hydrostatic fluid having at least one specified material carried therein, under <span class="hlt">pressure</span> which structurally distorts the lattice sufficiently to permit entry of the at least one specified material. The microporous material is capable of undergoing a temporary structural distortion which alters resting lattice dimensions under increased ambient <span class="hlt">pressure</span> and at least partially returning to rest lattice dimensions when returned to ambient <span class="hlt">pressure</span>. The <span class="hlt">pressure</span> of the fluid is then reduced to permit return to at least partial resting lattice dimension while the at least one specified material is therein. By this method, at least one specified material is captured in the microporous material to form a modified microporous material.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22282886','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22282886"><span>Observable <span class="hlt">induced</span> gravitational <span class="hlt">waves</span> from an early matter phase</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Alabidi, Laila; Sasaki, Misao; Kohri, Kazunori; Sendouda, Yuuiti E-mail: kohri@post.kek.jp E-mail: sendouda@cc.hirosaki-u.ac.jp</p> <p>2013-05-01</p> <p>Assuming that inflation is succeeded by a phase of matter domination, which corresponds to a low temperature of reheating T{sub r} < 10{sup 9}GeV, we evaluate the spectra of gravitational <span class="hlt">waves</span> <span class="hlt">induced</span> in the post-inflationary universe. We work with models of hilltop-inflation with an enhanced primordial scalar spectrum on small scales, which can potentially lead to the formation of primordial black holes. We find that a lower reheat temperature leads to the production of gravitational <span class="hlt">waves</span> with energy densities within the ranges of both space and earth based gravitational <span class="hlt">wave</span> detectors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18927387','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18927387"><span>Current-<span class="hlt">induced</span> spin-<span class="hlt">wave</span> Doppler shift.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vlaminck, Vincent; Bailleul, Matthieu</p> <p>2008-10-17</p> <p>Spin transfer appears to be a promising tool for improving spintronics devices. Experiments that quantitatively access the magnitude of the spin transfer are required for a fundamental understanding of this phenomenon. By inductively measuring spin <span class="hlt">waves</span> propagating along a permalloy strip subjected to a large electrical current, we observed a current-<span class="hlt">induced</span> spin <span class="hlt">wave</span> Doppler shift that we relate to the adiabatic spin transfer torque. Because spin <span class="hlt">waves</span> provide a well-defined system for performing spin transfer, we anticipate that they could be used as an accurate probe of spin-polarized transport in various itinerant ferromagnets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA494236','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA494236"><span>Modeling of Acoustic <span class="hlt">Pressure</span> <span class="hlt">Waves</span> in Level-Dependent Earplugs</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2008-09-01</p> <p>18 Figure 16. Comparison of experimental and predicted <span class="hlt">pressure</span> response; M4 rifle at 1 m. ........19...range). The impulse events were created using an M4 rifle , a shortened variant of the M16A2. Figure 2 shows a typical test setup. The earplugs were...<span class="hlt">pressure</span> levels at the head were created by firing the M4 rifle at varying distances from the manikin. Distances of 0.25, 0.5, 1, 2, 4, 8, 16, 32, and 64</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18315341','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18315341"><span>New ultrasonic Bleustein-Gulyaev <span class="hlt">wave</span> method for measuring the viscosity of liquids at high <span class="hlt">pressure</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kiełczyński, P; Szalewski, M; Siegoczyński, R M; Rostocki, A J</p> <p>2008-02-01</p> <p>In this paper, a new method for measuring the viscosity of liquids at high <span class="hlt">pressure</span> is presented. To this end the authors have applied an ultrasonic method using the Bleustein-Gulyaev (BG) surface acoustic <span class="hlt">wave</span>. By applying the perturbation method, we can prove that the change in the complex propagation constant of the BG <span class="hlt">wave</span> produced by the layer of liquid loading the waveguide surface is proportional to the shear mechanical impedance of the liquid. In the article, a measuring setup employing the BG <span class="hlt">wave</span> for the purpose of measuring the viscosity of liquids at high <span class="hlt">pressure</span> (up to 1 GPa) is presented. The results of high-<span class="hlt">pressure</span> viscosity measurements of triolein and castor oil are also presented. In this paper the model of a Newtonian liquid was applied. Using this new method it is also possible to measure the viscosity of liquids during the phase transition and during the decompression process (hysteresis of the dependence of viscosity on <span class="hlt">pressure</span>).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008RScI...79b6109K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008RScI...79b6109K"><span>New ultrasonic Bleustein-Gulyaev <span class="hlt">wave</span> method for measuring the viscosity of liquids at high <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kiełczyński, P.; Szalewski, M.; Siegoczyński, R. M.; Rostocki, A. J.</p> <p>2008-02-01</p> <p>In this paper, a new method for measuring the viscosity of liquids at high <span class="hlt">pressure</span> is presented. To this end the authors have applied an ultrasonic method using the Bleustein-Gulyaev (BG) surface acoustic <span class="hlt">wave</span>. By applying the perturbation method, we can prove that the change in the complex propagation constant of the BG <span class="hlt">wave</span> produced by the layer of liquid loading the waveguide surface is proportional to the shear mechanical impedance of the liquid. In the article, a measuring setup employing the BG <span class="hlt">wave</span> for the purpose of measuring the viscosity of liquids at high <span class="hlt">pressure</span> (up to 1GPa) is presented. The results of high-<span class="hlt">pressure</span> viscosity measurements of triolein and castor oil are also presented. In this paper the model of a Newtonian liquid was applied. Using this new method it is also possible to measure the viscosity of liquids during the phase transition and during the decompression process (hysteresis of the dependence of viscosity on <span class="hlt">pressure</span>).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850054401&hterms=plasma+neutral+gas+interaction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dplasma%2Bneutral%2Bgas%2Binteraction','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850054401&hterms=plasma+neutral+gas+interaction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dplasma%2Bneutral%2Bgas%2Binteraction"><span><span class="hlt">Wave</span>-particle interactions <span class="hlt">induced</span> by SEPAC on Spacelab 1 <span class="hlt">Wave</span> observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Taylor, W. W. L.; Obayashi, T.; Kawashima, N.; Sasaki, S.; Yanagisawa, M.; Burch, J. L.; Reasoner, D. L.; Roberts, W. T.</p> <p>1985-01-01</p> <p>Space experiments with particle accelerators (SEPAC) flew on Spacelab 1 in November and December 1983. SEPAC included an accelerator which emitted electrons into the ionospheric plasma with energies up to 5 keV and currents up to 300 mA. The SEPAC equipment also included an energetic plasma generator, a neutral gas generator, and an extensive array of diagnostics. The diagnostics included plasma <span class="hlt">wave</span> detectors, and energetic electron analyzer, a photometer, a high sensitivity television camera, a Langmuir probe and a <span class="hlt">pressure</span> gage. Twenty-eight experiments were performed during the mission to investigate beam-plasma interactions, electron beam dynamics, plasma beam propagation, and vehicle charging. The <span class="hlt">wave</span>-particle interactions were monitored by the plasma <span class="hlt">wave</span> instrumentation, by the energetic electron detector and by the optical detectors. All show evidence of <span class="hlt">wave</span>-particle interactions, which are described in this paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12126667','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12126667"><span>A one-dimensional model for the propagation of transient <span class="hlt">pressure</span> <span class="hlt">waves</span> through the lung.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Grimal, Quentin; Watzky, Alexandre; Naili, Salah</p> <p>2002-08-01</p> <p>The propagation of <span class="hlt">pressure</span> <span class="hlt">waves</span> in the lung has been investigated by many authors concerned with respiratory physiology, ultrasound medical techniques or thoracic impact injuries. In most of the theoretical studies, the lung has been modeled as an isotropic and homogeneous medium, and by using Hooke's constitutive law (see e.g. Ganesan et al. Respir. Physiol. 110 (1997) 19; Jahed et al. J. Appl. Physiol. 66 (1989) 2675; Grimal et al. C.R. Acad. Sci., Paris 329 (IIb) (2001) 655-662), or more elaborated material laws (see, e.g. Bush and Challener (Proceedings of the International Research Council on Biokinetics Impacts (IRCOBI), Bergish-gladbach, 1988); Stuhmiller et al. J. Trauma 28 (1988) S132; Yang and Wang, Finite element modeling of the human thorax. Web page: http://wwwils.nlm.nih.gov/research/visible/vhpconf98/AUTHORS/YANG/YANG.HTM.). The hypothesis of homogeneous medium may be inappropriate for certain problems. Because of its foam-like structure, the behavior of the lung-even if the air and the soft tissue are assumed to behave like linearly elastic materials-is susceptible to be frequency dependent. In the present study, the lung is viewed as a one-dimensional stack of air and soft tissue layers; <span class="hlt">wave</span> propagation in such a stack can be investigated in an equivalent mass-spring chain (El-Raheb (J. Acoust. Soc. Am. 94 (1993) 172; Int. J. Solids Struct. 34 (1997) 2969), where the masses and springs, respectively, represent the alveolar walls and alveolar gas. Results are presented in the time and frequency domains. The frequency dependence (cutoff frequency, variations in phase velocity) of the lung model is found to be highly dependent on the mean alveolar size. We found that short pulses <span class="hlt">induced</span> by high velocity impacts (bullet stopped by a bulletproof jacket) can be highly distorted during the propagation. The <span class="hlt">pressure</span> differential between two alveoli is discussed as a possible injury criterion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhPro..67.1083C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhPro..67.1083C"><span>Modelling and Experimental Verification of <span class="hlt">Pressure</span> <span class="hlt">Wave</span> Following Gaseous Helium Storage Tank Rupture</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chorowski, M.; Grabowski, M.; Jędrusyna, A.; Wach, J.</p> <p></p> <p>Helium inventory in high energy accelerators, tokamaks and free electron lasers may exceed tens of tons. The gaseous helium is stored in steel tanks under a <span class="hlt">pressure</span> of about 20 bar and at environment temperature. Accidental rupture of any of the tanks filled with the gaseous helium will create a rapid energy release in form of physical blast. An estimation of <span class="hlt">pressure</span> <span class="hlt">wave</span> distribution following the tank rupture and potential consequences to the adjacent research infrastructure and buildings is a very important task, critical in the safety aspect of the whole cryogenic system. According to the present regulations the TNT equivalent approach is to be applied to evaluate the <span class="hlt">pressure</span> <span class="hlt">wave</span> following a potential gas storage tank rupture. A special test stand was designed and built in order to verify experimentally the blast effects in controlled conditions. In order to obtain such a shock <span class="hlt">wave</span> a <span class="hlt">pressurized</span> plastic tank was used. The tank was ruptured and the resulting <span class="hlt">pressure</span> <span class="hlt">wave</span> was recorded using a spatially-distributed array of <span class="hlt">pressure</span> sensors connected to a high-speed data acquisition device. The results of the experiments and the comparison with theoretical values obtained from thermodynamic model of the blast are presented. A good agreement between the simulated and measured data was obtained. Recommendations regarding the applicability of thermodynamic model of physical blast versus TNT approach, to estimate consequences of gas storage tank rupture are formulated. The laboratory scale experimental results have been scaled to ITER <span class="hlt">pressurized</span> helium storage tanks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23953966','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23953966"><span>Impulses and <span class="hlt">pressure</span> <span class="hlt">waves</span> cause excitement and conduction in the nervous system.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Barz, Helmut; Schreiber, Almut; Barz, Ulrich</p> <p>2013-11-01</p> <p>It is general accepted, that nerval excitement and conduction is caused by voltage changes. However, the influx of fluid into an elastical tube releases impulses or <span class="hlt">pressure</span> <span class="hlt">waves</span>. Therefore an influx of ion currents, respectively fluid motions into the elastic neuronal cells and fibres also <span class="hlt">induce</span> impulses. This motion of charge carriers are measured by voltage devices as oscillations or action potentials, but the voltage changes may be an epiphenomenon of the (mechanical) impulses. Impulse <span class="hlt">waves</span> can have a high speed. As stiffer or inelastic a tube wall, the greater is the speed of the impulse. Myelin sheaths cause a significant stiffening of the nerve fibre wall and myelinated fibres have a conduction velocity up to 120 m/s. The influx of fluid at the nodes of Ranvier intensifies periodically the impulse <span class="hlt">wave</span> in the nerve fibres. The authors suggest that also the muscle end-plate acts as a conductor of axonal impulses to the inner of the muscle fibres and that the exocytosis of acetylcholine into the synaptic cleft may be an amplifier of the axonal impulse. It is discussed that intracellular actin filaments may also influence motions at the neuronal membrane. Many sensory nerve cells are excited due to exogenous or endogenous mechanical impulses. It may plausible that such impulses are conducted directly to the sensory nerve cell bodies in the dorsal root ganglia without the transformation in electric energy. Excitation conduction happens without noteworthy energy consumption because the flow of ion currents through the membranes takes place equivalent to the concentration gradient. Impulse <span class="hlt">waves</span> cause short extensions of the lipid membranes of the cell- and fibres walls and therefore they can <span class="hlt">induce</span> opening and closing of the included ion channels. This mechanism acts to "voltage gated" and "ligand-gated" channels likewise. The concept of neuronal impulses can be helpful to the understanding of other points of neurophysiology or neuronal diseases. This includes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.3719F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.3719F"><span>Deep-water bedforms <span class="hlt">induced</span> by refracting Internal Solitary <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Falcini, Federico; Droghei, Riccardo; Casalbore, Daniele; Martorelli, Eleonora; Mosetti, Renzo; Sannino, Gianmaria; Santoleri, Rosalia; Latino Chiocci, Francesco</p> <p>2017-04-01</p> <p>Subaqueous bedforms (or sand <span class="hlt">waves</span>) are typically observed in those environments that are exposed to strong currents, characterized by a dominant unidirectional flow. However, sand-<span class="hlt">wave</span> fields may be also observed in marine environments where no such current exists; the physical processes driving their formation are enigmatic or not well understood. We propose that internal solitary <span class="hlt">waves</span> (ISWs), <span class="hlt">induced</span> by tides, can produce an effective, unidirectional boundary flow filed that forms asymmetric sand <span class="hlt">waves</span>. We test this idea by examining a sand-<span class="hlt">wave</span> field off the Messina Strait, where we hypothesize that ISWs formed at the interface between intermediate and surface waters are refracted by topography. Hence, we argue that the deflected pattern (i.e., the depth-dependent orientation) of the sand-<span class="hlt">wave</span> field is due to refraction of such ISWs. Combining field observations and numerical modelling, we show that ISWs can account for three key features: ISWs produce fluid velocities capable of mobilizing bottom sediments; the predicted refraction pattern resulting from the interaction of ISWs with bottom topography matches the observed deflection of the sand <span class="hlt">waves</span>; and predicted migration rates of sand <span class="hlt">waves</span> match empirical estimates. This work shows how ISWs may contribute to sculpting the structure of continental margins and it represents a promising link between the geological and oceanographic communities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18408124','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18408124"><span><span class="hlt">Wave</span> reflection augments central systolic and pulse <span class="hlt">pressures</span> during facial cooling.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Edwards, David G; Roy, Matthew S; Prasad, Raju Y</p> <p>2008-06-01</p> <p>Cardiovascular events are more common in the winter months, possibly because of hemodynamic alterations in response to cold exposure. The purpose of this study was to determine the effect of acute facial cooling on central aortic <span class="hlt">pressure</span>, arterial stiffness, and <span class="hlt">wave</span> reflection. Twelve healthy subjects (age 23 +/- 3 yr; 6 men, 6 women) underwent supine measurements of carotid-femoral pulse <span class="hlt">wave</span> velocity (PWV), brachial artery blood <span class="hlt">pressure</span>, and central aortic <span class="hlt">pressure</span> (via the synthesis of a central aortic <span class="hlt">pressure</span> waveform by radial artery applanation tonometry and generalized transfer function) during a control trial (supine rest) and a facial cooling trial (0 degrees C gel pack). Aortic augmentation index (AI), an index of <span class="hlt">wave</span> reflection, was calculated from the aortic <span class="hlt">pressure</span> waveform. Measurements were made at baseline, 2 min, and 7 min during each trial. Facial cooling increased (P < 0.05) peripheral and central diastolic and systolic <span class="hlt">pressures</span>. Central systolic <span class="hlt">pressure</span> increased more than peripheral systolic <span class="hlt">pressure</span> (22 +/- 3 vs. 15 +/- 2 mmHg; P < 0.05), resulting in decreased pulse <span class="hlt">pressure</span> amplification ratio. Facial cooling resulted in a robust increase in AI and a modest increase in PWV (AI: -1.4 +/- 3.8 vs. 21.2 +/- 3.0 and 19.9 +/- 3.6%; PWV: 5.6 +/- 0.2 vs. 6.5 +/- 0.3 and 6.2 +/- 0.2 m/s; P < 0.05). Change in mean arterial <span class="hlt">pressure</span> but not PWV predicted the change in AI, suggesting that facial cooling may increase AI independent of aortic PWV. Facial cooling and the resulting peripheral vasoconstriction are associated with an increase in <span class="hlt">wave</span> reflection and augmentation of central systolic <span class="hlt">pressure</span>, potentially explaining ischemia and cardiovascular events in the cold.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PMB....57..329R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PMB....57..329R"><span>The impact of hepatic <span class="hlt">pressurization</span> on liver shear <span class="hlt">wave</span> speed estimates in constrained versus unconstrained conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rotemberg, V.; Palmeri, M.; Nightingale, R.; Rouze, N.; Nightingale, K.</p> <p>2012-01-01</p> <p>Increased hepatic venous <span class="hlt">pressure</span> can be observed in patients with advanced liver disease and congestive heart failure. This elevated portal <span class="hlt">pressure</span> also leads to variation in acoustic radiation-force-derived shear <span class="hlt">wave</span>-based liver stiffness estimates. These changes in stiffness metrics with hepatic interstitial <span class="hlt">pressure</span> may confound stiffness-based predictions of liver fibrosis stage. The underlying mechanism for this observed stiffening behavior with <span class="hlt">pressurization</span> is not well understood and is not explained with commonly used linear elastic mechanical models. An experiment was designed to determine whether the stiffness increase exhibited with hepatic <span class="hlt">pressurization</span> results from a strain-dependent hyperelastic behavior. Six excised canine livers were subjected to variations in interstitial <span class="hlt">pressure</span> through cannulation of the portal vein and closure of the hepatic artery and hepatic vein under constrained conditions (in which the liver was not free to expand) and unconstrained conditions. Radiation-force-derived shear <span class="hlt">wave</span> speed estimates were obtained and correlated with <span class="hlt">pressure</span>. Estimates of hepatic shear stiffness increased with changes in interstitial <span class="hlt">pressure</span> over a physiologically relevant range of <span class="hlt">pressures</span> (0-35 mmHg) from 1.5 to 3.5 m s-1. These increases were observed only under conditions in which the liver was free to expand while <span class="hlt">pressurized</span>. This behavior is consistent with hyperelastic nonlinear material models that could be used in the future to explore methods for estimating hepatic interstitial <span class="hlt">pressure</span> noninvasively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.S11A1009W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.S11A1009W"><span>Atmospheric <span class="hlt">Pressure</span> Oscillations Forced by Surface <span class="hlt">Waves</span> From the 2003 Tokachi-Oki Earthquake</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Watada, S.; Nishida, K.; Sekiguchi, S.</p> <p>2004-12-01</p> <p>Clear atmospheric <span class="hlt">pressure</span> changes associated with the 2003 Tokachi-Oki Earthquake with M 8.3 were recorded by 8 microbarographs along Japan. The maximum oscillatory <span class="hlt">pressure</span> change is about 2 Pascal with dominant period is about 15-20 second, and lasted for more than 30 minutes. Comparing the <span class="hlt">pressure</span> change with broadband seismic records observed near or at the microbarogram, the <span class="hlt">pressure</span> change starts at the arrival of seismic <span class="hlt">waves</span> and reaches its maximum amplitude at the arrival of Rayleigh <span class="hlt">waves</span>. Four microbarographs, co-located with STS-1 broadband seismographs and suffering less atmospheric wind noise, show that peaks in vertical ground velocity records correspond to the peaks of atmospheric <span class="hlt">pressure</span> records. Similar <span class="hlt">pressure</span> changes were observed during the largest aftershock (M 7.4). All ground motion analyzed in this paper were recorded by STS-1 broadband sensors. Spectrum analysis in the frequency domain supports that the vertical ground velocity and the <span class="hlt">pressure</span> change has the same phase and the amplitude ratio is constant up to a period of about 50 second. The constant amplitude ratio is about (atmospheric density) times (sound velocity in the atmosphere), indicating that the surface ground in vertical ground motion compresses or inflates the air above the ground locally and low-frequency sound <span class="hlt">waves</span> are generated. <span class="hlt">Pressure</span> change recorded after the passage of Rayleigh <span class="hlt">waves</span> does not well correlate with the ground velocity. Through the precise atmospheric <span class="hlt">pressure</span> and ground motion measurement at the same sites, we witnessed the process of low-frequency sound generation by the vertical ground surface motion acted as a vibrating plate of a speaker. The radiated low-frequency sound <span class="hlt">waves</span> propagates upward and reaches to the ionosphere with large amplitude because of the energy conservation. The ionospheric turbulence reported in the past researches were originated from this low-frequency sound at the ground surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhPl...24e2108I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhPl...24e2108I"><span>Solitary <span class="hlt">waves</span> in a degenerate relativistic plasma with ionic <span class="hlt">pressure</span> anisotropy and electron trapping effects</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Irfan, M.; Ali, S.; Mirza, Arshad M.</p> <p>2017-05-01</p> <p>The dynamics of obliquely propagating ion-acoustic (IA) <span class="hlt">waves</span> in the presence of ionic <span class="hlt">pressure</span> anisotropy and electron trapping effects is studied in a dense magnetoplasma, containing degenerate relativistic trapped electrons and dynamical (classical) ions. By using the plane <span class="hlt">wave</span> solution, a modified linear dispersion relation for IA <span class="hlt">waves</span> is derived and analyzed with different limiting cases and various plasma parameters both analytically and numerically. For nonlinear analysis, a reductive perturbation technique is employed to obtain a Zakharov-Kuznetsov equation involving the weakly nonlinear IA excitations. It is shown that the electron thermal correction and ionic <span class="hlt">pressure</span> anisotropy strongly modify the <span class="hlt">wave</span> amplitudes and width attributed to weakly nonlinear IA <span class="hlt">waves</span>. The stability criterion for stable/unstable solitary pulses is also discussed with variations of angle (β) and temperature ratio (σ). A reduction and domain splitting of unstable excitations into sub-domains with stable and unstable potential pulses are pointed out for electron temperature ratio in the range of 0.01 < σ < 0.3 for degenerate relativistic trapped electrons. Moreover, the ionic <span class="hlt">pressure</span> anisotropy also considerably affects the stability of solitary potentials in the non-relativistic and ultra-relativistic regimes. The obtained results might be useful for understanding the nonlinear dynamics and propagation characteristics of <span class="hlt">waves</span> in superdense plasmas, in the environments of white dwarfs and neutron stars, where the electron thermal and ionic <span class="hlt">pressure</span> anisotropy effects cannot be ignored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013NatSR...3E1735M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013NatSR...3E1735M"><span><span class="hlt">Inducing</span> Peer <span class="hlt">Pressure</span> to Promote Cooperation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mani, Ankur; Rahwan, Iyad; Pentland, Alex</p> <p>2013-04-01</p> <p>Cooperation in a large society of self-interested individuals is notoriously difficult to achieve when the externality of one individual's action is spread thin and wide on the whole society. This leads to the `tragedy of the commons' in which rational action will ultimately make everyone worse-off. Traditional policies to promote cooperation involve Pigouvian taxation or subsidies that make individuals internalize the externality they incur. We introduce a new approach to achieving global cooperation by localizing externalities to one's peers in a social network, thus leveraging the power of peer-<span class="hlt">pressure</span> to regulate behavior. The mechanism relies on a joint model of externalities and peer-<span class="hlt">pressure</span>. Surprisingly, this mechanism can require a lower budget to operate than the Pigouvian mechanism, even when accounting for the social cost of peer <span class="hlt">pressure</span>. Even when the available budget is very low, the social mechanisms achieve greater improvement in the outcome.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23619166','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23619166"><span><span class="hlt">Inducing</span> peer <span class="hlt">pressure</span> to promote cooperation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mani, Ankur; Rahwan, Iyad; Pentland, Alex</p> <p>2013-01-01</p> <p>Cooperation in a large society of self-interested individuals is notoriously difficult to achieve when the externality of one individual's action is spread thin and wide on the whole society. This leads to the 'tragedy of the commons' in which rational action will ultimately make everyone worse-off. Traditional policies to promote cooperation involve Pigouvian taxation or subsidies that make individuals internalize the externality they incur. We introduce a new approach to achieving global cooperation by localizing externalities to one's peers in a social network, thus leveraging the power of peer-<span class="hlt">pressure</span> to regulate behavior. The mechanism relies on a joint model of externalities and peer-<span class="hlt">pressure</span>. Surprisingly, this mechanism can require a lower budget to operate than the Pigouvian mechanism, even when accounting for the social cost of peer <span class="hlt">pressure</span>. Even when the available budget is very low, the social mechanisms achieve greater improvement in the outcome.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3636514','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3636514"><span><span class="hlt">Inducing</span> Peer <span class="hlt">Pressure</span> to Promote Cooperation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mani, Ankur; Rahwan, Iyad; Pentland, Alex</p> <p>2013-01-01</p> <p>Cooperation in a large society of self-interested individuals is notoriously difficult to achieve when the externality of one individual's action is spread thin and wide on the whole society. This leads to the ‘tragedy of the commons’ in which rational action will ultimately make everyone worse-off. Traditional policies to promote cooperation involve Pigouvian taxation or subsidies that make individuals internalize the externality they incur. We introduce a new approach to achieving global cooperation by localizing externalities to one's peers in a social network, thus leveraging the power of peer-<span class="hlt">pressure</span> to regulate behavior. The mechanism relies on a joint model of externalities and peer-<span class="hlt">pressure</span>. Surprisingly, this mechanism can require a lower budget to operate than the Pigouvian mechanism, even when accounting for the social cost of peer <span class="hlt">pressure</span>. Even when the available budget is very low, the social mechanisms achieve greater improvement in the outcome. PMID:23619166</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.2968S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.2968S"><span>Particle transport model sensitivity on <span class="hlt">wave-induced</span> processes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Staneva, Joanna; Ricker, Marcel; Krüger, Oliver; Breivik, Oyvind; Stanev, Emil; Schrum, Corinna</p> <p>2017-04-01</p> <p>Different effects of wind <span class="hlt">waves</span> on the hydrodynamics in the North Sea are investigated using a coupled <span class="hlt">wave</span> (WAM) and circulation (NEMO) model system. The terms accounting for the <span class="hlt">wave</span>-current interaction are: the Stokes-Coriolis force, the sea-state dependent momentum and energy flux. The role of the different Stokes drift parameterizations is investigated using a particle-drift model. Those particles can be considered as simple representations of either oil fractions, or fish larvae. In the ocean circulation models the momentum flux from the atmosphere, which is related to the wind speed, is passed directly to the ocean and this is controlled by the drag coefficient. However, in the real ocean, the <span class="hlt">waves</span> play also the role of a reservoir for momentum and energy because different amounts of the momentum flux from the atmosphere is taken up by the <span class="hlt">waves</span>. In the coupled model system the momentum transferred into the ocean model is estimated as the fraction of the total flux that goes directly to the currents plus the momentum lost from <span class="hlt">wave</span> dissipation. Additionally, we demonstrate that the <span class="hlt">wave-induced</span> Stokes-Coriolis force leads to a deflection of the current. During the extreme events the Stokes velocity is comparable in magnitude to the current velocity. The resulting <span class="hlt">wave-induced</span> drift is crucial for the transport of particles in the upper ocean. The performed sensitivity analyses demonstrate that the model skill depends on the chosen processes. The results are validated using surface drifters, ADCP, HF radar data and other in-situ measurements in different regions of the North Sea with a focus on the coastal areas. The using of a coupled model system reveals that the newly introduced <span class="hlt">wave</span> effects are important for the drift-model performance, especially during extremes. Those effects cannot be neglected by search and rescue, oil-spill, transport of biological material, or larva drift modelling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhPl...23k2709L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhPl...23k2709L"><span>The thermodynamical instability <span class="hlt">induced</span> by <span class="hlt">pressure</span> ionization in fluid helium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Qiong; Liu, Hai-Feng; Zhang, Gong-Mu; Zhao, Yan-Hong; Lu, Guo; Tian, Ming-Feng; Song, Hai-Feng</p> <p>2016-11-01</p> <p>A systematic study of <span class="hlt">pressure</span> ionization is carried out in the chemical picture by the example of fluid helium. By comparing the variants of the chemical model, it is demonstrated that the behavior of <span class="hlt">pressure</span> ionization depends on the construction of the free energy function. In the chemical model with the Coulomb free energy described by the Padé interpolation formula, thermodynamical instability <span class="hlt">induced</span> by <span class="hlt">pressure</span> ionization is found to be manifested by a discontinuous drop or a continuous fall and rise along the <span class="hlt">pressure</span>-density curve as well as the <span class="hlt">pressure</span>-temperature curve, which is very much like the first order liquid-liquid phase transition of fluid hydrogen from the first principles simulations. In contrast, in the variant chemical model with the Coulomb free energy term empirically weakened, no thermodynamical instability is <span class="hlt">induced</span> when <span class="hlt">pressure</span> ionization occurs, and the resulting equation of state achieves a good agreement with the first principles simulations of fluid helium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004ASAJ..116..417A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004ASAJ..116..417A"><span>Prediction of the characteristics of two types of <span class="hlt">pressure</span> <span class="hlt">waves</span> in the cochlea: Theoretical considerations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Andoh, Masayoshi; Wada, Hiroshi</p> <p>2004-07-01</p> <p>The aim of this study was to predict the characteristics of two types of cochlear <span class="hlt">pressure</span> <span class="hlt">waves</span>, so-called fast and slow <span class="hlt">waves</span>. A two-dimensional finite-element model of the organ of Corti (OC), including fluid-structure interaction with the surrounding lymph fluid, was constructed. The geometry of the OC at the basal turn was determined from morphological measurements of others in the gerbil hemicochlea. As far as mechanical properties of the materials within the OC are concerned, previously determined mechanical properties of portions within the OC were adopted, and unknown mechanical features were determined from the published measurements of static stiffness. Time advance of the fluid-structure scheme was achieved by a staggered approach. Using the model, the magnitude and phase of the fast and slow <span class="hlt">waves</span> were predicted so as to fit the numerically obtained <span class="hlt">pressure</span> distribution in the scala tympani with what is known about intracochlear <span class="hlt">pressure</span> measurement. When the predicted <span class="hlt">pressure</span> <span class="hlt">waves</span> were applied to the model, the numerical result of the velocity of the basilar membrane showed good agreement with the experimentally obtained velocity of the basilar membrane documented by others. Thus, the predicted <span class="hlt">pressure</span> <span class="hlt">waves</span> appeared to be reliable. Moreover, it was found that the fluid-structure interaction considerably influences the dynamic behavior of the OC at frequencies near the characteristic frequency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28106407','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28106407"><span>Matter-<span class="hlt">Wave-Optical-Wave</span> Mixing-<span class="hlt">Induced</span> Transparency and a Nonhyperbolic Matter-<span class="hlt">Wave</span> Quasisoliton in Quantum Gases.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Yan; Zhu, Chengjie; Garrett, W R; Hagley, E W; Deng, L</p> <p>2017-01-06</p> <p>The realization of atomic quantum gases has brought out surprising effects that have no correspondence in nonlinear optics with thermal gases, presenting intriguing and exciting challenges to the research discipline of nonlinear optics which has matured since the invention of the laser. Here, we show an unexpected optical <span class="hlt">wave</span>-mixing gain cancellation effect in a quantum gas that restricts an, otherwise, strongly enhanced backward-propagating light-matter <span class="hlt">wave</span>-mixing process. This results in a <span class="hlt">wave</span>-mixing <span class="hlt">induced</span> transparency and a nonhyperbolic quasi-matter-<span class="hlt">wave</span> soliton that opens new research opportunities in hydrodynamic fluid research of degenerate quantum gases, such as phonon scattering in a two-dimensional sonic black hole horizon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvL.118a3901L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvL.118a3901L"><span>Matter-<span class="hlt">Wave-Optical-Wave</span> Mixing-<span class="hlt">Induced</span> Transparency and a Nonhyperbolic Matter-<span class="hlt">Wave</span> Quasisoliton in Quantum Gases</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Yan; Zhu, Chengjie; Garrett, W. R.; Hagley, E. W.; Deng, L.</p> <p>2017-01-01</p> <p>The realization of atomic quantum gases has brought out surprising effects that have no correspondence in nonlinear optics with thermal gases, presenting intriguing and exciting challenges to the research discipline of nonlinear optics which has matured since the invention of the laser. Here, we show an unexpected optical <span class="hlt">wave</span>-mixing gain cancellation effect in a quantum gas that restricts an, otherwise, strongly enhanced backward-propagating light-matter <span class="hlt">wave</span>-mixing process. This results in a <span class="hlt">wave</span>-mixing <span class="hlt">induced</span> transparency and a nonhyperbolic quasi-matter-<span class="hlt">wave</span> soliton that opens new research opportunities in hydrodynamic fluid research of degenerate quantum gases, such as phonon scattering in a two-dimensional sonic black hole horizon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16024572','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16024572"><span>Waveform dispersion, not reflection, may be the major determinant of aortic <span class="hlt">pressure</span> <span class="hlt">wave</span> morphology.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hope, Sarah A; Tay, David B; Meredith, Ian T; Cameron, James D</p> <p>2005-12-01</p> <p>The objective of this study was to investigate the determinants of aortic <span class="hlt">pressure</span> waveform morphology in the thoracoabdominal aorta with specific reference to features of potential prognostic value for cardiovascular disease. In particular, we aimed to determine the location of major <span class="hlt">pressure</span> <span class="hlt">wave</span> reflection sites within the aorta. Aortic <span class="hlt">pressure</span> waveforms were acquired with 2-Fr Millar Mikro-tip catheter transducers in 40 subjects (26 men, 14 women), and repeated in 10 subjects, at five predetermined points within the aorta: aortic root, transverse arch, and at the levels of the diaphragm, renal arteries, and aortic bifurcation. Waveforms were analyzed for augmentation index (AI), time to inflection point (Ti), and <span class="hlt">pressure</span> parameters. AI decreased progressively between the aortic root and bifurcation (P < 0.001), and Ti increased (P < 0.01). There was the expected progressive peripheral amplification of systolic and pulse <span class="hlt">pressures</span> and fall in time to peak <span class="hlt">pressure</span> (all P < 0.001). There was no difference on repeat pullback or between sexes. These data are at variance with the concept that central AI results solely from <span class="hlt">pressure</span> <span class="hlt">wave</span> reflection, when Ti would be expected to decrease and AI increase with distal progression. <span class="hlt">Pressure</span> <span class="hlt">wave</span> propagation phenomena may contribute, and the potential role of frequency dispersion merits investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSM31A2452C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSM31A2452C"><span>Electromagnetic Ion Cyclotron <span class="hlt">Wave</span> Triggering by Solar Wind Dynamic <span class="hlt">Pressure</span> Enhancements at Multiple Locations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cho, J.; Lee, D. Y.; Kim, H.</p> <p>2016-12-01</p> <p>Electromagnetic Ion cyclotron (EMIC) <span class="hlt">waves</span> are one of the key plasma <span class="hlt">waves</span> which play a critical role in the magnetosphere by interacting with charged particles. One of the generation mechanisms of EMIC <span class="hlt">waves</span> is magnetospheric compression due to impact of enhanced solar wind dynamic <span class="hlt">pressure</span> Pdyn. With the multi-satellite (the Van Allen Probes and two GOES satellites) observations in the inner magnetosphere and ground-based magnetometers, we examine two EMIC <span class="hlt">wave</span> events that are triggered by Pdyn enhancements under prolonged northward IMF quiet time preconditions. For both events, the impact of enhanced Pdyn causes EMIC <span class="hlt">waves</span> at multiple points. However, we find a strong spatial dependence of EMIC <span class="hlt">wave</span> triggering and the accompanied <span class="hlt">wave</span> properties. For Event 1, a satellite near noon observes no dramatic EMIC <span class="hlt">waves</span>. In contrast, three other satellites are situated at a nearly same dawn side zone but at slightly different L shells and see notable EMIC <span class="hlt">waves</span> but in different frequencies relative to local ion gyrofrequencies. These <span class="hlt">waves</span> are found inside or outer edge of the plasmasphere. For Event 2, the satellites are situated at three different MLT zones, late afternoon-dusk, early evening-pre-midnight, and post-midnight, when they see the triggered EMIC <span class="hlt">waves</span>. They are again found at different frequencies relative to local ion gyrofrequencies, and all outside the plasmasphere. Furthermore, the triggered EMIC <span class="hlt">waves</span> for both events are observed from high-latitude ground stations in Antarctica. The results in this work imply that triggering of EMIC <span class="hlt">waves</span> by enhanced Pdyn can occur at multiple points but with different <span class="hlt">wave</span> properties, which must be due to different local plasma and magnetic conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1002428','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1002428"><span><span class="hlt">Pressure-induced</span> superconductivity in europium metal</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Debessai, M.; Matsuoka, T.; Hamlin, J.J.; Bi, W.; Meng, Y.; Shimizu, K.; Schilling, J.S.</p> <p>2010-05-24</p> <p>Of the 52 known elemental superconductors among the 92 naturally occurring elements in the periodic table, fully 22 only become superconducting under sufficiently high <span class="hlt">pressure</span>. In the rare-earth metals, the strong local magnetic moments originating from the 4f shell suppress superconductivity. For Eu, however, Johansson and Rosengren have suggested that sufficiently high <span class="hlt">pressures</span> should promote one of its 4f electrons into the conduction band, changing Eu from a strongly magnetic (J=7/2) 4f{sup 7}-state into a weak Van Vleck paramagnetic (J=0) 4f{sup 6}-state, thus opening the door for superconductivity, as in Am (5f{sup 6}). We report that Eu becomes superconducting above 1.8 K for <span class="hlt">pressures</span> exceeding 80 GPa, T{sub c} increasing linearly with <span class="hlt">pressure</span> to 142 GPa at the rate +15 mK/GPa. Eu thus becomes the 53rd elemental superconductor in the periodic table. Synchrotron x-ray diffraction studies to 92 GPa at ambient temperature reveal four structural phase transitions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApPhL.110r4102J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApPhL.110r4102J"><span>Characterization of an <span class="hlt">induced</span> <span class="hlt">pressure</span> pumping force for microfluidics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiang, Hai; Fan, Na; Peng, Bei; Weng, Xuan</p> <p>2017-05-01</p> <p>The electro-osmotic pumping and <span class="hlt">pressure</span>-driven manipulation of fluids are considered as the most common strategies in microfluidic devices. However, both of them exhibit major disadvantages such as hard integration and high reagent consumption, and they are destructive methods for detection and photo bleaching. In this paper, an electric field-effect flow control approach, combining the electro-osmotic pumping force and the <span class="hlt">pressure</span>-driven pumping force, was developed to generate the <span class="hlt">induced</span> <span class="hlt">pressure</span>-driven flow in a T-shaped microfluidic chip. Electro-osmotic flow between the T-intersection and two reservoirs was demonstrated, and it provided a stable, continuous, and electric field-free flow in the section of the microchannel without the electrodes. The velocity of the <span class="hlt">induced</span> <span class="hlt">pressure</span>-driven flow was linearly proportional to the applied voltages. Both numerical and experimental investigations were conducted to prove the concept, and the experimental results showed good agreement with the numerical simulations. In comparison to other <span class="hlt">induced</span> <span class="hlt">pressure</span> pumping methods, this approach can <span class="hlt">induce</span> a high and controllable <span class="hlt">pressure</span> drop in the electric field-free segment, subsequently causing an <span class="hlt">induced</span> <span class="hlt">pressure</span>-driven flow for transporting particles or biological cells. In addition, the generation of bubbles and the blocking of the microchannel are avoided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900018862','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900018862"><span>Atmospheric planetary <span class="hlt">waves</span> <span class="hlt">induced</span> by solar rotation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Krivolutsky, A. A.</p> <p>1989-01-01</p> <p>It is known that there are variations in the atmospheric processes with a period close to that of the rotation of the Sun (27 days). The variations are discovered in tropospheric processes, rainfalls, geopotential and in stratosphere. The main theoretical problem is the identification of the physical process by which these heterogeneous solar and meteorological phenomena are connected. Ivanovsky and Krivolutsky proposed that the periodic heating of the ozone layer by the short <span class="hlt">wave</span> radiation would be the reason of excitation the 27-day oscillations. It was also assumed that excitement takes place in condition of resonance with an excited mode corresponding to the conditions present in the stratospheric circulations. The possibility is discussed of the resonant excitation and presentation is made of the data analysis results which support this idea.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003PhDT........51Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003PhDT........51Z"><span>Optimization of <span class="hlt">pressure</span> waveform, distribution and sequence in shock <span class="hlt">wave</span> lithotripsy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhou, Yufeng</p> <p></p> <p>This work aims to improve shock <span class="hlt">wave</span> lithotripsy (SWL) technology by increasing stone comminution efficiency while reducing simultaneously the propensity of tissue injury. First, the mechanism of vascular injury in SWL was investigated. Based on in vitro vessel phantom experiment and theoretical calculation, it was found that SWL-<span class="hlt">induced</span> large intraluminal bubble expansion may constitute a primary mechanism for the rupture of capillaries and small blood vessels. However, when the large intraluminal bubble expansion is suppressed by inversion of the <span class="hlt">pressure</span> waveform of the lithotripter shock <span class="hlt">wave</span> (LSW), rupture of a 200-mum cellulose hollow fiber vessel phantom can be avoided. Based on these experimental observations and theoretical assessment of bubble dynamics using the Gilmore model an in situ pulse superposition technique was developed to reduce tissue injury without compromising stone comminution in SWL. A thin shell ellipsoidal reflector insert was fabricated to fit snugly with the original HM-3 reflector. Using the Hamilton model, the effects of reflector geometry on the pulse profile and sequence of the shock <span class="hlt">waves</span> were evaluated qualitatively. Guided by this analysis, the design of the reflector insert had been refined to suppress the intraluminal bubble expansion, which was confirmed by high-speed imaging of bubble dynamics both in free field and inside a vessel phantom. The pulse <span class="hlt">pressure</span>, beam size and stone comminution efficiency of the upgraded reflector were all found to be comparable to those of the original reflector. However, the greatest difference lies in the propensity for tissue injury. At the lithotripter focus, about 30 shocks are needed to cause a rupture of the vessel phantom using the original reflector, but no rupture can be produced after 200 shocks by the upgraded reflector. Overall, the upgraded reflector could significantly reduce the propensity of vessel rupture while maintaining satisfactory stone comminution. Second, to improve</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23107159','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23107159"><span><span class="hlt">Wave</span> reflection quantification based on <span class="hlt">pressure</span> waveforms alone--methods, comparison, and clinical covariates.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hametner, Bernhard; Wassertheurer, Siegfried; Kropf, Johannes; Mayer, Christopher; Holzinger, Andreas; Eber, Bernd; Weber, Thomas</p> <p>2013-03-01</p> <p>Within the last decade the quantification of pulse <span class="hlt">wave</span> reflections mainly focused on measures of central aortic systolic <span class="hlt">pressure</span> and its augmentation through reflections based on pulse <span class="hlt">wave</span> analysis (PWA). A complementary approach is the <span class="hlt">wave</span> separation analysis (WSA), which quantifies the total amount of arterial <span class="hlt">wave</span> reflection considering both aortic pulse and flow <span class="hlt">waves</span>. The aim of this work is the introduction and comparison of aortic blood flow models for WSA assessment. To evaluate the performance of the proposed modeling approaches (Windkessel, triangular and averaged flow), comparisons against Doppler measurements are made for 148 patients with preserved ejection fraction. Stepwise regression analysis between WSA and PWA parameters are performed to provide determinants of methodological differences. Against Doppler measurement mean difference and standard deviation of the amplitudes of the decomposed forward and backward <span class="hlt">pressure</span> <span class="hlt">waves</span> are comparable for Windkessel and averaged flow models. Stepwise regression analysis shows similar determinants between Doppler and Windkessel model only. The results indicate that the Windkessel method provides accurate estimates of <span class="hlt">wave</span> reflection in subjects with preserved ejection fraction. The comparison with waveforms derived from Doppler ultrasound as well as recently proposed simple triangular and averaged flow <span class="hlt">waves</span> showed that this approach may reduce variability and provide realistic results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20719817','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20719817"><span>The acute effects of smokeless tobacco on central aortic blood <span class="hlt">pressure</span> and <span class="hlt">wave</span> reflection characteristics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Martin, Jeffrey S; Beck, Darren T; Gurovich, Alvaro N; Braith, Randy W</p> <p>2010-10-01</p> <p>The main objectives of this study were to examine the acute effect of a single dose of smokeless tobacco (ST) on central aortic blood <span class="hlt">pressure</span> and <span class="hlt">wave</span> reflection characteristics. Fifteen apparently healthy male subjects (aged 30.6 ± 6.2 y) were given a 2.5 g oral dose of ST after baseline measurements were recorded. Pulse <span class="hlt">wave</span> analysis using radial artery applanation tonometry was performed in triplicate at baseline (0 min) and at 10-min intervals during (10, 20 and 30 min) and after (40, 50 and 60 min) ST use. An acute dose of ST was associated with a significant increase in heart rate (HR), central aortic systolic and diastolic blood <span class="hlt">pressure</span>, peripheral brachial systolic and diastolic blood <span class="hlt">pressure</span>, and aortic augmentation index normalized to a fixed heart rate of 75 bpm (AIx@75). Furthermore, ejection duration and round trip travel time of the reflected <span class="hlt">pressure</span> <span class="hlt">wave</span> (Δt(p)) were significantly decreased as a result of one time ST use. As a result of changes in aortic <span class="hlt">pressure</span> <span class="hlt">wave</span> reflection characteristics, there was a significant increase in wasted left ventricular <span class="hlt">pressure</span> energy (LVE(w)) and the tension-time index (TTI) as a result of ST use. In conclusion, one time use of ST elicits significant transient increases in HR, central aortic <span class="hlt">pressures</span>, AIx@75, the TTI and LVE(w). Chronic users subjected to decades of elevated central <span class="hlt">pressures</span> and left ventricular work may have an increased cardiovascular risk as central aortic <span class="hlt">pressures</span> are even more strongly related to cardiovascular outcomes than peripheral blood <span class="hlt">pressures</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2971534','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2971534"><span>The acute effects of smokeless tobacco on central aortic blood <span class="hlt">pressure</span> and <span class="hlt">wave</span> reflection characteristics</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Martin, Jeffrey S; Beck, Darren T; Gurovich, Alvaro N; Braith, Randy W</p> <p>2010-01-01</p> <p>The main objectives of this study were to examine the acute effect of a single dose of smokeless tobacco (ST) on central aortic blood <span class="hlt">pressure</span> and <span class="hlt">wave</span> reflection characteristics. Fifteen apparently healthy male subjects (aged 30.6 ± 6.2 y) were given a 2.5 g oral dose of ST after baseline measurements were recorded. Pulse <span class="hlt">wave</span> analysis using radial artery applanation tonometry was performed in triplicate at baseline (0 min) and at 10-min intervals during (10, 20 and 30 min) and after (40, 50 and 60 min) ST use. An acute dose of ST was associated with a significant increase in heart rate (HR), central aortic systolic and diastolic blood <span class="hlt">pressure</span>, peripheral brachial systolic and diastolic blood <span class="hlt">pressure</span>, and aortic augmentation index normalized to a fixed heart rate of 75 bpm (AIx@75). Furthermore, ejection duration and round trip travel time of the reflected <span class="hlt">pressure</span> <span class="hlt">wave</span> (Δtp) were significantly decreased as a result of one time ST use. As a result of changes in aortic <span class="hlt">pressure</span> <span class="hlt">wave</span> reflection characteristics, there was a significant increase in wasted left ventricular <span class="hlt">pressure</span> energy (LVEw) and the tension–time index (TTI) as a result of ST use. In conclusion, one time use of ST elicits significant transient increases in HR, central aortic <span class="hlt">pressures</span>, AIx@75, the TTI and LVEw. Chronic users subjected to decades of elevated central <span class="hlt">pressures</span> and left ventricular work may have an increased cardiovascular risk as central aortic <span class="hlt">pressures</span> are even more strongly related to cardiovascular outcomes than peripheral blood <span class="hlt">pressures</span>. PMID:20719817</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17510503','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17510503"><span>Relationship between radial and central arterial pulse <span class="hlt">wave</span> and evaluation of central aortic <span class="hlt">pressure</span> using the radial arterial pulse <span class="hlt">wave</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Takazawa, Kenji; Kobayashi, Hideyuki; Shindo, Naohisa; Tanaka, Nobuhiro; Yamashina, Akira</p> <p>2007-03-01</p> <p>Since a decrease of central aortic <span class="hlt">pressure</span> contributes to the prevention of cardiovascular events, simple measurement of not only brachial blood <span class="hlt">pressure</span> but also central aortic <span class="hlt">pressure</span> may be useful in the prevention and treatment of cardiovascular diseases. In this study, we simultaneously measured radial artery pulse <span class="hlt">waves</span> non-invasively and ascending aortic <span class="hlt">pressure</span> invasively, before and after the administration of nicorandil. We then compared changes in central aortic <span class="hlt">pressure</span> and radial arterial blood <span class="hlt">pressure</span> calibrated with brachial blood <span class="hlt">pressure</span> in addition to calculating the augmentation index (AI) at the aorta and radial artery. After nicorandil administration, the reduction in maximal systolic blood <span class="hlt">pressure</span> in the aorta (Deltaa-SBP) was -14+/-15 mmHg, significantly larger than that in early systolic <span class="hlt">pressure</span> in the radial artery (Deltar-SBP) (-9+/-12 mmHg). The reduction in late systolic blood <span class="hlt">pressure</span> in the radial artery (Deltar-SBP2) was -15+/-14 mmHg, significantly larger than Deltar-SBP, but not significantly different from Deltaa-SBP. There were significant relationships between Deltaa-SBP and Deltar-SBP (r=0.81, p<0.001), and between Deltaa-SBP and Deltar-SBP2 (r=0.91, p<0.001). The slope of the correlation regression line with Deltar-SBP2 (0.83) was larger and closer to 1 than that with Deltar-SBP (0.63), showing that the relationship was close to 1:1. Significant correlations were obtained between aortic AI (a-AI) and radial AI (r-AI) (before nicorandil administration: r=0.91, p<0.001; after administration: r=0.70, p<0.001). These data suggest that the measurement of radial artery pulse <span class="hlt">wave</span> and observation of changes in the late systolic blood <span class="hlt">pressure</span> in the radial artery (r-SBP2) in addition to the ordinary measurement of brachial blood <span class="hlt">pressure</span> may enable a more accurate evaluation of changes in maximal systolic blood <span class="hlt">pressure</span> in the aorta (a-SBP).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17702839','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17702839"><span>Oscillatory <span class="hlt">pressure</span> <span class="hlt">wave</span> transmission from the upper airway to the carotid artery.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Howitt, Lauren; Kairaitis, Kristina; Kirkness, Jason P; Garlick, Sarah R; Wheatley, John R; Byth, Karen; Amis, Terence C</p> <p>2007-11-01</p> <p>Snoring-associated vibration energy transmission from the upper airway to the carotid artery has been hypothesized as a potential atherosclerotic plaque initiating/rupturing event that may provide a pathogenic mechanism linking snoring and embolic stroke. We examined transmission of oscillatory <span class="hlt">pressure</span> <span class="hlt">waves</span> from the pharyngeal lumen to the common carotid artery wall and lumen in seven male, anesthetized, spontaneously breathing New Zealand White rabbits. Airflow was monitored via a pneumotachograph inserted in series in the intact trachea. Fifteen 20-s runs of, separately, 40-, 60-, and 90-Hz oscillatory <span class="hlt">pressure</span> <span class="hlt">waves</span> [<span class="hlt">pressure</span> amplitude in the trachea (Ptr(amp)), amplitude 2-20 cmH(2)O] were generated by a loudspeaker driven by a sine <span class="hlt">wave</span> generator and amplifier and superimposed on tidal breathing via the cranial tracheal connector. <span class="hlt">Pressure</span> transducer-tipped catheters measured <span class="hlt">pressure</span> amplitudes in the tissues adjacent to the common carotid artery bifurcation (Pcti(amp)) and within the lumen (carotid sinus; Pcs(amp)). Data were analyzed using power spectrum analysis and linear mixed-effects statistical modeling. Both the frequency (f) and amplitude of the injected <span class="hlt">pressure</span> <span class="hlt">wave</span> influenced Pcti(amp) and Pcs(amp), in that ln Pcti(amp) = 1.2(Ptr(amp)) + 0.02(f) - 5.2, and ln Pcs(amp) = 0.6(Ptr(amp)) + 0.02(f) - 4.9 (both P < 0.05). Across all frequencies tested, transfer of oscillatory <span class="hlt">pressure</span> across the carotid artery wall was associated with an amplitude gain, as expressed by a Pcs(amp)-to-Pcti(amp) ratio of 1.8 +/- 0.3 (n = 6). Our findings confirm transmission of oscillatory <span class="hlt">pressure</span> <span class="hlt">waves</span> from the upper airway lumen to the peripharyngeal tissues and across the carotid artery wall to the lumen. Further studies are required to establish the role of this incident energy in the pathogenesis of carotid artery vascular disease.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009OcMod..29..189B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009OcMod..29..189B"><span><span class="hlt">Wave-induced</span> upper-ocean mixing in a climate model of intermediate complexity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Babanin, Alexander V.; Ganopolski, Andrey; Phillips, William R. C.</p> <p></p> <p>Climate modelling, to a great extent, is based on simulating air-sea interactions at larger scales. Small-scale interactions and related phenomena, such as wind-generated <span class="hlt">waves</span> and <span class="hlt">wave-induced</span> turbulence are sub-grid processes for such models and therefore cannot be simulated explicitly. In the meantime, the <span class="hlt">waves</span> play the principal role in the upper-ocean mixing. This role is usually parameterized, mostly to account for the <span class="hlt">wave</span>-breaking turbulence and to describe downward diffusion of such turbulence. The main purpose of the paper is to demonstrate that an important physical mechanism, that is the ocean mixing due to <span class="hlt">waves</span>, is presently missing in the climate models, whereas the effect of this mixing is significant. It is argued that the mixing role of the surface <span class="hlt">waves</span> is not limited to the mere transfer of the wind stress and energy across the ocean interface by means of breaking and surface currents. The <span class="hlt">waves</span> facilitate two processes in the upper-ocean which can deliver turbulence to the depths of the order of 100 m directly, rather than diffusing it from the surface. The first process is due to capacity of the <span class="hlt">waves</span> to generate turbulence, unrelated to the <span class="hlt">wave</span> breaking, at all depths where the <span class="hlt">wave</span> orbital motion is significant. The second process is Langmuir circulation, triggered by the <span class="hlt">waves</span>. Such <span class="hlt">wave</span>-controlled mixing should cause seasonal variations of the mixed-layer depth, which regulates the thermodynamic balance between the ocean and atmosphere. In the present paper, these variations are parameterized in terms of the global winds. The variable mixed-layer depth is then introduced in the climate model of intermediated complexity CLIMBER-2 with a purpose of reproducing the pre-industrial climate. Comparisons are conducted with the NRL global atlas of the mixed layer, and performance of the <span class="hlt">wave</span>-mixing parameterisations was found satisfactory in circumstances where the mixing is expected to be dominated by the wind-generated <span class="hlt">waves</span>. It is shown that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/582279','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/582279"><span>Shear flow <span class="hlt">induced</span> <span class="hlt">wave</span> couplings in the solar wind</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Poedts, S.; Rogava, A.D. |; Mahajan, S.M. |</p> <p>1998-01-01</p> <p>A sheared background flow in a plasma <span class="hlt">induces</span> coupling between different MHD <span class="hlt">wave</span> modes, resulting in their mutual transformations with corresponding energy redistributing between the modes. In this way, the energy can be transfered from one <span class="hlt">wave</span> mode to the other, but energy can also be added to or extracted from the background flow. In the present paper it is investigated whether the <span class="hlt">wave</span> coupling and energy transfer mechanisms can operate under solar wind conditions. It is shown that this is indeed the case. Hence, the long-period <span class="hlt">waves</span> observed in the solar wind at r > 0.3 AU might be generated by much faster periodic oscillations in the photosphere of the Sun. Other possible consequences for observable beat phenomena in the wind and the acceleration of the solar wind particles are also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003SPIE.5035..223M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003SPIE.5035..223M"><span>Image reconstruction with acoustic radiation force <span class="hlt">induced</span> shear <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McAleavey, Stephen A.; Nightingale, Kathryn R.; Stutz, Deborah L.; Hsu, Stephen J.; Trahey, Gregg E.</p> <p>2003-05-01</p> <p>Acoustic radiation force may be used to <span class="hlt">induce</span> localized displacements within tissue. This phenomenon is used in Acoustic Radiation Force Impulse Imaging (ARFI), where short bursts of ultrasound deliver an impulsive force to a small region. The application of this transient force launches shear <span class="hlt">waves</span> which propagate normally to the ultrasound beam axis. Measurements of the displacements <span class="hlt">induced</span> by the propagating shear <span class="hlt">wave</span> allow reconstruction of the local shear modulus, by <span class="hlt">wave</span> tracking and inversion techniques. Here we present in vitro, ex vivo and in vivo measurements and images of shear modulus. Data were obtained with a single transducer, a conventional ultrasound scanner and specialized pulse sequences. Young's modulus values of 4 kPa, 13 kPa and 14 kPa were observed for fat, breast fibroadenoma, and skin. Shear modulus anisotropy in beef muscle was observed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMEP53F1047Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMEP53F1047Z"><span>Multiscale Modeling of <span class="hlt">Wave-induced</span> Flow in Vegetation Canopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhu, L.; Chen, Q. J.; Chakrabarti, A.; Ma, G.</p> <p>2016-12-01</p> <p>Coastal vegetation dissipates the <span class="hlt">wave</span> energy and alters local hydrodynamics by enhancing within-canopy turbulence, and introducing significant spatial variability to the flow. The modeling of flows and <span class="hlt">waves</span> through vegetation has attracted the attention of coastal and hydraulics engineers for decades. The ability to predict instantaneous flow characteristics and turbulent flow structures accurately is of great significance for modeling <span class="hlt">wave</span> attenuation and sediment transport in vegetated area. Two widely used types of modeling approaches are the Reynolds-averaged Navier-Stokes (RANS) and the Large Eddy Simulations (LES). The high level of detail delivered by the LES model comes with significantly large computational costs. The objective of this study is to investigate the flow structure and turbulence properties predicted by both methods and explore the applicability of multi-scale modeling of <span class="hlt">wave-induced</span> flow in vegetation canopy. In this study, two models, NHWAVE and OpenFOAM, are utilized to simulate <span class="hlt">wave-induced</span> flows in emergent and submerged vegetation. A standard k-ɛ turbulence model and a LES model are used in NHWAVE and OpenFOAM, respectively. NHWAVE employs a Morrison-type quadratic equation to approximate the <span class="hlt">wave-induced</span> drag on vegetation stems, whereas OpenFOAM adopts a direct approach and resolves flow structure within the canopy using the high-resolution LES-based turbulence model. Both models are firstly validated against laboratory data for free surface and vertical variation of mean velocity. Reynolds stresses calculated directly from the LES model is compared with modeled Reynolds stresses from the RANS model and the influence of vertical variation of the turbulence structures on the mean canopy flow elucidated. Implications on <span class="hlt">wave</span> energy dissipation and sediment transport are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/969241','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/969241"><span><span class="hlt">Pressure</span> Dependence of the Charge-Density-<span class="hlt">Wave</span> Gap in Rare-Earth Tri-Tellurides</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sacchetti, A.; Arcangeletti, E.; Perucchi, A.; Baldassarre, L.; Postorino, P.; Lupi, S.; Ru, N.; Fisher, I.R.; Degiorgi, L.; /Zurich, ETH</p> <p>2009-12-14</p> <p>We investigate the <span class="hlt">pressure</span> dependence of the optical properties of CeTe{sub 3}, which exhibits an incommensurate charge-density-<span class="hlt">wave</span> (CDW) state already at 300 K. Our data are collected in the mid-infrared spectral range at room temperature and at <span class="hlt">pressures</span> between 0 and 9 GPa. The energy for the single particle excitation across the CDW gap decreases upon increasing the applied <span class="hlt">pressure</span>, similarly to the chemical <span class="hlt">pressure</span> by rare-earth substitution. The broadening of the bands upon lattice compression removes the perfect nesting condition of the Fermi surface and therefore diminishes the impact of the CDW transition on the electronic properties of RTe{sub 3}.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JChPh.145p4504S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JChPh.145p4504S"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> polymerization of fluid ethylene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scelta, Demetrio; Ceppatelli, Matteo; Bini, Roberto</p> <p>2016-10-01</p> <p>The spontaneous polymerization of fluid ethylene under high temperature and <span class="hlt">pressure</span> conditions has been characterized by using FTIR absorption spectroscopy. The fluid has been isobarically heated at <span class="hlt">pressures</span> ranging between 0.4 and 1.5 GPa by means of a resistively heated membrane diamond anvil cell. Besides tracing the instability boundary for spontaneous polymerization in the fluid, we have also measured the reaction kinetics at 1.5 GPa and temperatures ranging between 340 and 423 K. From the rate constants the activation energy of the overall reaction could be computed, information that joined to the molecularity of the initiation step provides some insight about the reaction mechanism. The polymers recovered from the different reactions have been characterized by FTIR, Raman, and X-ray diffraction revealing in all the cases a crystalline material of astonishing quality, likely related to the growth of the polymer in the hot fluid monomer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..DFDH36002E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..DFDH36002E"><span><span class="hlt">Pressure</span> gradient <span class="hlt">induced</span> generation of microbubbles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Evangelio, Alvaro; Campo-Cortes, Francisco; Gordillo, Jose Manuel</p> <p>2015-11-01</p> <p>It is well known that the controlled production of monodisperse bubbles possesses uncountable applications in medicine, pharmacy and industry. Here we provide with a detailed physical description of the bubble formation processes taking place in a type of flow where the liquid <span class="hlt">pressure</span> gradient can be straightforwardly controlled. In our experiments, a gas flow rate discharges through a cylindrical needle into a <span class="hlt">pressurized</span> chamber. The <span class="hlt">pressure</span> gradient created from the exit of the injection needle towards the entrance of a extraction duct promotes the stretching of the gas ligament downstream. In our analysis, which is supported by an exhaustive experimental study in which the liquid viscosity is varied by three orders of magnitude, different regimes can be distinguished depending mainly on the Reynolds number. Through our physical modeling, we provide closed expressions for both the bubbling frequencies and for the bubble diameters as well as the conditions under which a monodisperse generation is obtained in all regimes found. The excellent agreement between our expressions and the experimental data fully validates our physical modeling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12471251','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12471251"><span>Cavitation-<span class="hlt">induced</span> reactions in high-<span class="hlt">pressure</span> carbon dioxide.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kuijpers, M W A; van Eck, D; Kemmere, M F; Keurentjes, J T F</p> <p>2002-12-06</p> <p>The feasibility of ultrasound-<span class="hlt">induced</span> in situ radical formation in liquid carbon dioxide was demonstrated. The required threshold <span class="hlt">pressure</span> for cavitation could be exceeded at a relatively low acoustic intensity, as the high vapor <span class="hlt">pressure</span> of CO2 counteracts the hydrostatic <span class="hlt">pressure</span>. With the use of a dynamic bubble model, the formation of hot spots upon bubble collapse was predicted. Cavitation-<span class="hlt">induced</span> radical formation was used for the polymerization of methyl methacrylate in CO2, yielding high-molecular-weight polymers. These results show that sonochemical reactions can be performed in dense-phase fluids, which allows the environmentally benign CO2 to replace conventional organic solvents in many reaction systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4641481','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4641481"><span>Unusual U <span class="hlt">wave</span> <span class="hlt">induced</span> by reconstructed retrosternal esophagus</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Yamagata, Kenichiro; Uno, Kansei; Mori, Kazuhiko; Seto, Yasuyuki</p> <p>2015-01-01</p> <p>Key Clinical Message The present case shows that a broad compression of the right ventricle by the reconstructed stomach tube after esophagus cancer surgery <span class="hlt">induced</span> an abnormal U <span class="hlt">wave</span>. When facing an abnormal ECG, we should keep in mind of the mechanical compression to the heart as a differential diagnosis. PMID:26576279</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EPJD...70..183D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EPJD...70..183D"><span>Molecular dynamics study of accelerated ion-<span class="hlt">induced</span> shock <span class="hlt">waves</span> in biological media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Vera, Pablo; Mason, Nigel J.; Currell, Fred J.; Solov'yov, Andrey V.</p> <p>2016-09-01</p> <p>We present a molecular dynamics study of the effects of carbon- and iron-ion <span class="hlt">induced</span> shock <span class="hlt">waves</span> in DNA duplexes in liquid water. We use the CHARMM force field implemented within the MBN Explorer simulation package to optimize and equilibrate DNA duplexes in liquid water boxes of different sizes and shapes. The translational and vibrational degrees of freedom of water molecules are excited according to the energy deposited by the ions and the subsequent shock <span class="hlt">waves</span> in liquid water are simulated. The <span class="hlt">pressure</span> <span class="hlt">waves</span> generated are studied and compared with an analytical hydrodynamics model which serves as a benchmark for evaluating the suitability of the simulation boxes. The energy deposition in the DNA backbone bonds is also monitored as an estimation of biological damage, something which is not possible with the analytical model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010APS..MARV33009D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010APS..MARV33009D"><span>Surface Acoustic <span class="hlt">Wave</span> <span class="hlt">Induced</span> Magnetic Switching</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Davis, S.; Baruth, A.; Adenwalla, S.</p> <p>2010-03-01</p> <p>We report on the use of Surface Acoustic <span class="hlt">Waves</span> (SAW) to switch the magnetization direction of lithographically patterned 40um by 10um cobalt rectangles between two titanium inter-digital transducers (IDTs) on Y-cut LiNbO3. Easy and hard axis magnetization loops measured using the magneto-optical Kerr effect (MOKE) show the expected in-plane shape anisotropy. After magnetic saturation along the long easy axis, the magnetic field is turned off and the IDT's are excited at the fundamental resonance frequency, 91.5 MHz, producing a SAW that travels across the patterned Co magnetic structure producing a fast time dependent mechanical strain parallel to the short hard axis of the Co. Magneto-elastic coupling results in a rotation of the magnetization into the hard axis direction, measured by in-plane MOKE measurements along the hard axis direction. Both dc MOKE and high frequency MOKE show, as expected, a definite turn on voltage followed by an asymptotic approach to saturation. Support from NSF MRSEC (DMR-0820521), UCARE, and NFC-Minnesota.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1210518R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1210518R"><span>Using <span class="hlt">pressure</span> and seismological broadband ocean data to model shear <span class="hlt">wave</span> velocities in the north Atlantic.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rios, Celia; Dahm, Torsten; Jegen, Marion</p> <p>2010-05-01</p> <p>Seafloor compliance is the transfer function between <span class="hlt">pressure</span> and vertical displacement at the seafloor Infragravity <span class="hlt">waves</span> in the oceanic layer have long periods in the range of 30 - 500 s and obey a simple frequency-wavenumber relation. Seafloor compliance from infragravity <span class="hlt">waves</span> can be analyzed with single station recordings to determinate sub-seafloor shear <span class="hlt">wave</span> velocities. Previous studies in the Pacific Ocean have demonstrated that reliable near-surface shear <span class="hlt">wave</span> profiles can be derived from infragravity <span class="hlt">wave</span> compliance. However, these studies indicate that, beside the water depth the compliance measurements are limited by instrument sensitivity, calibration uncertainties and possibly other effects. In this work seafloor compliance and infragravity <span class="hlt">waves</span> are observed at two different locations in the Atlantic Ocean: the Logatchev hydrothermal field at the Mid Atlantic Ridge and the Azores (Sao Miguel Island). The data was acquired with the broadband ocean compliance station developed at the University of Hamburg as well as ocean station from the German instrument pool for amphibian seismology (DEPAS) equipped with broadband seismometers and <span class="hlt">pressure</span> sensors. Vertical velocity and <span class="hlt">pressure</span> data were used to calculate power spectral densities and normalized compliance along two profiles (one in each location). Power spectral densities show a dominant peak at low frequencies (0.01-0.035Hz) limited by the expected cut-off frequency, which is dependent on the water depth at each station. The peak has been interpreted as a strong infragravity <span class="hlt">wave</span> with values between 10-14 and 10-11 (m/s2)2/Hz and 104 and 106 (Pa2)2/Hz for acceleration and <span class="hlt">pressure</span> respectively. The results show compliance values between 10-10 and 10-8 1/Pa and its estimations take into account the coherence between seismic and <span class="hlt">pressure</span> signals in order to confirm that the seismic signals in the infragravity <span class="hlt">waves</span> are caused by <span class="hlt">pressure</span> sources. Shear <span class="hlt">wave</span> velocity models, with depth resolution</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17614493','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17614493"><span>Characteristics of surface sound <span class="hlt">pressure</span> and absorption of a finite impedance strip for a grazing incident plane <span class="hlt">wave</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sum, K S; Pan, J</p> <p>2007-07-01</p> <p>Distributions of sound <span class="hlt">pressure</span> and intensity on the surface of a flat impedance strip flush-mounted on a rigid baffle are studied for a grazing incident plane <span class="hlt">wave</span>. The distributions are obtained by superimposing the unperturbed <span class="hlt">wave</span> (the specularly reflected <span class="hlt">wave</span> as if the strip is rigid plus the incident <span class="hlt">wave</span>) with the radiated <span class="hlt">wave</span> from the surface vibration of the strip excited by the unperturbed <span class="hlt">pressure</span>. The radiated <span class="hlt">pressure</span> interferes with the unperturbed <span class="hlt">pressure</span> and distorts the propagating plane <span class="hlt">wave</span>. When the plane <span class="hlt">wave</span> propagates in the baffle-strip-baffle direction, it encounters discontinuities in acoustical impedance at the baffle-strip and strip-baffle interfaces. The radiated <span class="hlt">pressure</span> is highest around the baffle-strip interface, but decreases toward the strip-baffle interface where the plane <span class="hlt">wave</span> distortion reduces accordingly. As the unperturbed and radiated <span class="hlt">waves</span> have different magnitudes and superimpose out of phase, the surface <span class="hlt">pressure</span> and intensity increase across the strip in the plane <span class="hlt">wave</span> propagation direction. Therefore, the surface absorption of the strip is nonzero and nonuniform. This paper provides an understanding of the surface <span class="hlt">pressure</span> and intensity behaviors of a finite impedance strip for a grazing incident plane <span class="hlt">wave</span>, and of how the distributed intensity determines the sound absorption coefficient of the strip.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22038687','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22038687"><span>Shock <span class="hlt">pressure</span> <span class="hlt">induced</span> by glass-confined laser shock peening: Experiments, modeling and simulation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wu Xianqian; Song Hongwei; Wei Yanpeng; Wang Xi; Huang Chenguang; Duan Zhuping</p> <p>2011-09-01</p> <p>The shock <span class="hlt">pressure</span> generated by the glass confined regime in laser shock peening and its attenuation in the target material are investigated. First, the particle velocity of the target back free surface <span class="hlt">induced</span> by laser generated shock <span class="hlt">pressure</span> of this regime is measured using a photonic Doppler velocimetry system. The temporal profile of the particle velocity at the back free surface, where the elastic precursor is captured, manifests a powerful diagnostic capability of this newly developed photonic Doppler velocimetry system for tracking the velocity on short time scales in shock-<span class="hlt">wave</span> experiments. Second, a coupling <span class="hlt">pressure</span> analytical model, in which the material constitutive models of confined layers and target material are considered, is proposed to predict the plasma <span class="hlt">pressure</span> profile at the surface of target. Furthermore, using the predicted shock <span class="hlt">pressure</span> profile as the input condition, the dynamic response of the target under the shock <span class="hlt">pressure</span> is simulated by LS-DYNA. The simulated back free surface velocity profile agrees well with that measured by the photonic Doppler velocimetry system. Finally, the attenuation behavior of stress <span class="hlt">waves</span> and particle velocities in the depth of the target is analyzed, and it indicates an exponential decay. The corresponding empirical formulas for the attenuation behavior are given based on the numerical results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JAP...109e3515D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JAP...109e3515D"><span>Barocaloric effect and the <span class="hlt">pressure</span> <span class="hlt">induced</span> solid state refrigerator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Oliveira, N. A.</p> <p>2011-03-01</p> <p>The current refrigerators are based on the heating and cooling of fluids under external <span class="hlt">pressure</span> variation. The great inconvenience of this refrigeration technology is the damage caused to the environment by the refrigerant fluids. In this paper, we discuss the magnetic barocaloric effect, i.e., the heating or cooling of magnetic materials under <span class="hlt">pressure</span> variation and its application in the construction of refrigerators using solid magnetic compounds as refrigerant materials and <span class="hlt">pressure</span> as the external agent. The discussion presented in this paper points out that such a <span class="hlt">pressure</span> <span class="hlt">induced</span> solid state refrigerator can be very interesting because it is not harmful to the environment and can exhibit a good performance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ChOE...31..418X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ChOE...31..418X"><span>Three-dimensional <span class="hlt">wave-induced</span> current model equations and radiation stresses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xia, Hua-yong</p> <p>2017-08-01</p> <p>After the approach by Mellor (2003, 2008), the present paper reports on a repeated effort to derive the equations for three-dimensional <span class="hlt">wave-induced</span> current. Via the vertical momentum equation and a proper coordinate transformation, the phase-averaged <span class="hlt">wave</span> dynamic <span class="hlt">pressure</span> is well treated, and a continuous and depth-dependent radiation stress tensor, rather than the controversial delta Dirac function at the surface shown in Mellor (2008), is provided. Besides, a phase-averaged vertical momentum flux over a sloping bottom is introduced. All the inconsistencies in Mellor (2003, 2008), pointed out by Ardhuin et al. (2008) and Bennis and Ardhuin (2011), are overcome in the presently revised equations. In a test case with a sloping sea bed, as shown in Ardhuin et al. (2008), the <span class="hlt">wave</span>-driving forces derived in the present equations are in good balance, and no spurious vertical circulation occurs outside the surf zone, indicating that Airy's <span class="hlt">wave</span> theory and the approach of Mellor (2003, 2008) are applicable for the derivation of the <span class="hlt">wave-induced</span> current model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GGG....17..442S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GGG....17..442S"><span>Dehydration-<span class="hlt">induced</span> porosity <span class="hlt">waves</span> and episodic tremor and slip</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Skarbek, Rob M.; Rempel, Alan W.</p> <p>2016-02-01</p> <p>Episodic tremor and slip (ETS) along the subduction interface takes place where there is abundant evidence for elevated, near-lithostatic pore <span class="hlt">pressures</span>, at sufficiently great depths (30-45 km) that chemical dehydration reactions must act as their dominant source. We simulate fluid and heat flow while tracking the location of a vertically oriented, one-dimensional column of material as it subducts through the slow slip and tremor zone. The material in the column is transformed through a <span class="hlt">pressure</span>-dependent and temperature-dependent dehydration reaction that we describe with a generalized nonlinear kinetic rate law. Column deformation is largely dominated by viscous creep, with a closure rate that depends linearly on porosity. This behavior causes the dehydration reaction to generate traveling porosity <span class="hlt">waves</span> that transport increased fluid <span class="hlt">pressures</span> within the slow slip region. To explore the possibility that the observed periodicity of slow slip and tremor in subduction zones can be explained by the migration of such porosity <span class="hlt">waves</span>, we derive a dispersion relation that accurately describes our numerical results. We also obtain an expression for how the thickness of the dehydrating layer is expected to vary as a function of the parameters in the reaction rate law. Although the amplitudes of pore <span class="hlt">pressure</span> perturbations rival those that are produced by known external forcings (e.g., tides or passing surface <span class="hlt">waves</span>), our analysis suggests that given reasonable estimates of rock viscosity, permeabilities in the range 6.5×10-15 to 5×10-10 m2 are required for porosity <span class="hlt">wave</span> trains to form at periods comparable to those of slow slip and tremor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/7412234','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/7412234"><span>Effects of transmural <span class="hlt">pressure</span> and muscular activity on pulse <span class="hlt">waves</span> in arteries.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rachev, A I</p> <p>1980-05-01</p> <p>Propagation of small amplitude harmonic <span class="hlt">waves</span> through a viscous incompressible fluid contained in an initially stressed elastic cylindrical tube is considered as a model of the pulse <span class="hlt">wave</span> propagation in arteries. The nonlinearity and orthotropy of the vascular material is taken into account. Muscular activity is introduced by means of an "active" tension in circumferential direction of the vessel. The frequency equation is obtained and it is solved numerically for the parameters of a human abdominal aorta. Conclusions concerning <span class="hlt">pressure</span>-dependence, age-dependence, and muscular activation-dependence of the <span class="hlt">wave</span> characteristics are drawn which are in accord with available experimental data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21538161','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21538161"><span>Propagation of terahertz <span class="hlt">waves</span> in an atmospheric <span class="hlt">pressure</span> microplasma with Epstein electron density profile</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yuan Chengxun; Zhou Zhongxiang; Zhang, Jingwen W.; Sun Hongguo; Wang He; Du Yanwei; Xiang Xiaoli</p> <p>2011-03-15</p> <p>Propagation properties of terahertz (THz) <span class="hlt">waves</span> in a bounded atmospheric-<span class="hlt">pressure</span> microplasma (AMP) are analyzed in this study. A modified Epstein profile model is used to simulate the electron density distribution caused by the plasma sheaths. By introducing the dielectric constant of a Drude-Lorentz model and using the method of dividing the plasma into a series of subslabs with uniform electron density, the coefficients of power reflection, transmission, and absorption are derived for a bounded microplasma structure. The effects of size of microplasma, electron density profile, and collision frequency on the propagation of THz <span class="hlt">waves</span> are analyzed numerically. The results indicate that the propagation of THz <span class="hlt">waves</span> in AMPs depend greatly on the above three parameters. It is demonstrated that the THz <span class="hlt">wave</span> can play an important role in AMPs diagnostics; meanwhile, the AMP can be used as a novel potential tool to control THz <span class="hlt">wave</span> propagation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22308923','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22308923"><span>Experimental observation of standing <span class="hlt">wave</span> effect in low-<span class="hlt">pressure</span> very-high-frequency capacitive discharges</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, Yong-Xin; Gao, Fei; Liu, Jia; Wang, You-Nian</p> <p>2014-07-28</p> <p>Radial uniformity measurements of plasma density were carried out by using a floating double probe in a cylindrical (21 cm in electrode diameter) capacitive discharge reactor driven over a wide range of frequencies (27–220 MHz). At low rf power, a multiple-node structure of standing <span class="hlt">wave</span> effect was observed at 130 MHz. The secondary density peak caused by the standing <span class="hlt">wave</span> effect became pronounced and shifts toward the axis as the driving frequency further to increase, indicative of a much more shortened standing-<span class="hlt">wave</span> wavelength. With increasing rf power, the secondary density peak shift toward the radial edge, namely, the standing-<span class="hlt">wave</span> wavelength was increased, in good qualitative agreement with the previous theory and simulation results. At higher <span class="hlt">pressures</span> and high frequencies, the rf power was primarily deposited at the periphery of the electrode, due to the fact that the <span class="hlt">waves</span> were strongly damped as they propagated from the discharge edge into the center.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007OcDyn..57..511O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007OcDyn..57..511O"><span><span class="hlt">Wave-induced</span> topographic formstress in baroclinic channel flow</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Olbers, Dirk; Lettmann, Karsten; Wolff, Jörg-Olaf</p> <p>2007-12-01</p> <p>Large-scale zonal flow driven across submarine topography establishes standing Rossby <span class="hlt">waves</span>. In the presence of stratification, the <span class="hlt">wave</span> pattern can be represented by barotropic and baroclinic Rossby <span class="hlt">waves</span> of mixed planetary topographic nature, which are locked to the topography. In the balance of momentum, the <span class="hlt">wave</span> pattern manifests itself as topographic formstress. This <span class="hlt">wave-induced</span> formstress has the net effect of braking the flow and reducing the zonal transport. Locally, it may lead to acceleration, and the parts <span class="hlt">induced</span> by the barotropic and baroclinic <span class="hlt">waves</span> may have opposing effects. This flow regime occurs in the circumpolar flow around Antarctica. The different roles that the <span class="hlt">wave-induced</span> formstress plays in homogeneous and stratified flows through a zonal channel are analyzed with the <Literal>BARBI</Literal> (BARotropic-Baroclinic-Interaction ocean model, Olbers and Eden, J Phys Oceanogr 33:2719-2737, 2003) model. It is used in complete form and in a low-order version to clarify the different regimes. It is shown that the barotropic formstress arises by topographic locking due to viscous friction and the baroclinic one due to eddy-<span class="hlt">induced</span> density advection. For the sinusoidal topography used in this study, the transport obeys a law in which friction and <span class="hlt">wave-induced</span> formstress act as additive resistances, and windstress, the effect of Ekman pumping on the density stratification, and the buoyancy forcing (diapycnal mixing of the stratified water column) of the potential energy stored in the stratification act as additive forcing functions. The dependence of the resistance on the system parameters (lateral viscosity ɛ, lateral diffusivity κ of eddy density advection, Rossby radius λ, and topography height δ) as well as the dependence of transport on the forcing functions are determined. While the current intensity in a channel with homogeneous density decreases from the viscous flat bottom case in an inverse quadratic law ~ δ -2 with increasing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JBO....19l5001K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JBO....19l5001K"><span>Characteristics of laser-<span class="hlt">induced</span> shock <span class="hlt">wave</span> injury to the inner ear of rats</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kurioka, Takaomi; Matsunobu, Takeshi; Niwa, Katsuki; Tamura, Atsushi; Kawauchi, Satoko; Satoh, Yasushi; Sato, Shunichi; Shiotani, Akihiro</p> <p>2014-12-01</p> <p>Recently, the number of blast injuries of the inner ear has increased in the general population. In blast-<span class="hlt">induced</span> inner ear injury, a shock <span class="hlt">wave</span> (SW) component in the blast <span class="hlt">wave</span> is considered to play an important role in sensorineural hearing loss. However, the mechanisms by which an SW affects inner ear tissue remain largely unknown. We aimed to establish a new animal model for SW-<span class="hlt">induced</span> inner ear injury by using laser-<span class="hlt">induced</span> SWs (LISWs) on rats. The LISWs were generated by irradiating an elastic laser target with 694-nm nanosecond pulses of a ruby laser. After LISW application to the cochlea through bone conduction, auditory measurements revealed the presence of inner ear dysfunction, the extent of which depended on LISW overpressure. A significantly lower survival rate of hair cells and spiral ganglion neurons, as well as severe oxidative damage, were observed in the inner ear exposed to an LISW. Although considerable differences in the <span class="hlt">pressure</span> characteristics exist between LISWs and SWs in real blast <span class="hlt">waves</span>, the functional and morphological changes shown by the present LISW-based model were similar to those observed in real blast-<span class="hlt">induced</span> injury. Thus, our animal model is expected to be useful for laboratory-based research of blast-<span class="hlt">induced</span> inner ear injury.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JAP...112i4319M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JAP...112i4319M"><span>Modeling and simulation of <span class="hlt">pressure</span> <span class="hlt">waves</span> generated by nano-thermite reactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martirosyan, Karen S.; Zyskin, Maxim; Jenkins, Charles M.; (Yuki) Horie, Yasuyuki</p> <p>2012-11-01</p> <p>This paper reports the modeling of <span class="hlt">pressure</span> <span class="hlt">waves</span> from the explosive reaction of nano-thermites consisting of mixtures of nanosized aluminum and oxidizer granules. Such nanostructured thermites have higher energy density (up to 26 kJ/cm3) and can generate a transient <span class="hlt">pressure</span> pulse four times larger than that from trinitrotoluene (TNT) based on volume equivalence. A plausible explanation for the high <span class="hlt">pressure</span> generation is that the reaction times are much shorter than the time for a shock <span class="hlt">wave</span> to propagate away from the reagents region so that all the reaction energy is dumped into the gaseous products almost instantaneously and thereby a strong shock <span class="hlt">wave</span> is generated. The goal of the modeling is to characterize the gas dynamic behavior for thermite reactions in a cylindrical reaction chamber and to model the experimentally measured <span class="hlt">pressure</span> histories. To simplify the details of the initial stage of the explosive reaction, it is assumed that the reaction generates a one dimensional shock <span class="hlt">wave</span> into an air-filled cylinder and propagates down the tube in a self-similar mode. Experimental data for Al/Bi2O3 mixtures were used to validate the model with attention focused on the ratio of specific heats and the drag coefficient. Model predictions are in good agreement with the measured <span class="hlt">pressure</span> histories.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApPhL.100d1908Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApPhL.100d1908Z"><span>Surface modification by subsurface <span class="hlt">pressure</span> <span class="hlt">induced</span> diffusion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zimmermann, Claus G.</p> <p>2012-01-01</p> <p>Polycrystalline Ag, covered with a nm thin siloxane layer, was irradiated with ultraviolet light in vacuum at 500 K. Ag particles of different aspect ratios, 50-1000 nm in size, formed on the surface, including a small fraction of nanorods. <span class="hlt">Pressurized</span> water vapor bubbles are created in the subsurface region by hydrogen radicals photo-chemically released by the siloxane layer. They provide the driving force for a diffusive material flux along grain boundaries to the surface. This mechanism was modeled and found to agree with the experimental timescale: approximately 300 h are required for a 1000 nm particle to form.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22025414','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22025414"><span>Surface modification by subsurface <span class="hlt">pressure</span> <span class="hlt">induced</span> diffusion</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zimmermann, Claus G.</p> <p>2012-01-23</p> <p>Polycrystalline Ag, covered with a nm thin siloxane layer, was irradiated with ultraviolet light in vacuum at 500 K. Ag particles of different aspect ratios, 50-1000 nm in size, formed on the surface, including a small fraction of nanorods. <span class="hlt">Pressurized</span> water vapor bubbles are created in the subsurface region by hydrogen radicals photo-chemically released by the siloxane layer. They provide the driving force for a diffusive material flux along grain boundaries to the surface. This mechanism was modeled and found to agree with the experimental timescale: approximately 300 h are required for a 1000 nm particle to form.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70025130','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70025130"><span>A mechanism for sustained groundwater <span class="hlt">pressure</span> changes <span class="hlt">induced</span> by distant earthquakes</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Brodsky, E.E.; Roeloffs, E.; Woodcock, D.; Gall, I.; Manga, M.</p> <p>2003-01-01</p> <p>Large sustained well water level changes (>10 cm) in response to distant (more than hundreds of kilometers) earthquakes have proven enigmatic for over 30 years. Here we use high sampling rates at a well near Grants Pass, Oregon, to perform the first simultaneous analysis of both the dynamic response of water level and sustained changes, or steps. We observe a factor of 40 increase in the ratio of water level amplitude to seismic <span class="hlt">wave</span> ground velocity during a sudden coseismic step. On the basis of this observation we propose a new model for coseismic pore <span class="hlt">pressure</span> steps in which a temporary barrier deposited by groundwater flow is entrained and removed by the more rapid flow <span class="hlt">induced</span> by the seismic <span class="hlt">waves</span>. In hydrothermal areas, this mechanism could lead to 4 ?? 10-2 MPa <span class="hlt">pressure</span> changes and triggered seismicity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22403272','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22403272"><span>Transport <span class="hlt">induced</span> by ion cyclotron range of frequencies <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zhang, Debing Xu, Yingfeng; Wang, Shaojie</p> <p>2014-11-15</p> <p>The Vlasov equation, which includes the effect of the ion cyclotron range of frequencies (ICRF) <span class="hlt">waves</span>, can be written as the Fokker-Planck equation which describes the quasilinear transport in phase space by using the Lie-transform method. The radial transport fluxes of particle, energy and parallel momentum driven by ICRF <span class="hlt">waves</span> in the slab geometry have been derived. The results show that the ICRF-<span class="hlt">induced</span> radial redistributions of particle, energy and parallel momentum are driven by the inhomogeneity in energy of the equilibrium distribution function, and related to the correlation between the excursion in the real space and the excursion in energy. For the case with strong asymmetry of k{sub y} spectrum, the ICRF-<span class="hlt">induced</span> radial transport driven by the energy inhomogeneity dominates the ICRF-<span class="hlt">induced</span> radial transport driven by the spatial inhomogeneity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApPhL.110g2401C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApPhL.110g2401C"><span>Voltage <span class="hlt">induced</span> mechanical/spin <span class="hlt">wave</span> propagation over long distances</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, C.; Barra, A.; Mal, A.; Carman, G.; Sepulveda, A.</p> <p>2017-02-01</p> <p>We simulated the generation and propagation of spin <span class="hlt">waves</span> (SWs) using two excitation methods, namely, magnetic field and voltage <span class="hlt">induced</span> strain. A fully coupled non-linear magnetoelastic model, combining Landau-Lifshitz-Gilbert with elastodynamic equations, is used to study the propagation characteristics of SWs in magnetoelastic materials. Simulation results show that for excitation frequencies above ferromagnetic resonance (FMR), SWs excited by voltage <span class="hlt">induced</span> strain propagate over longer distances compared to SWs excited by magnetic field. In addition, strain mediated SWs exhibit loss characteristics, which are relatively independent of the magnetic losses (Gilbert damping). Moreover, it is also shown that strain <span class="hlt">induced</span> SWs can also be excited at frequencies below FMR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001ChPhL..18.1240L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001ChPhL..18.1240L"><span><span class="hlt">Pressure</span> <span class="hlt">Induced</span> Phase Transition in TiB</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Feng-Ying; Chen, Liang-Chen; Wang, Li-Jun; Gu, Hui-Cheng; Wang, Ru-Ju; Che, Rong-Zheng; Shen, Zhong-Yi</p> <p>2001-09-01</p> <p>In situ high <span class="hlt">pressure</span> x-ray diffraction and electrical resistance experiments on TiB have been carried out by using a diamond anvil cell device. The results revealed that the sample undergoes a first-order phase transition at <span class="hlt">pressures</span> of 3.5-5.0 GPa and 4.0-5.5 GPa for the x-ray diffraction and electrical resistance experiments, respectively. The parameters of the state equation are calculated before and after the phase transition and compared with the values calculated by Mohn et al. [J. Phys. C: Solid State Phys. 21 (1988) 2829] using the augmented spherical <span class="hlt">wave</span> method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA095342','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA095342"><span>Charge Design Considerations and Their Effect on <span class="hlt">Pressure</span> <span class="hlt">Waves</span> in Guns</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1980-12-01</p> <p>with his invention, the recording crusher gage. The significance of <span class="hlt">pressure</span> <span class="hlt">waves</span>, their origin and connection with high <span class="hlt">pressure</span> and catastrophic...motion. In the second configuration, foam nodules were dispersed in the bed to 2 • expand it fully to the closure plug. The experimental results shown in...PRIMER PROPELLANT BED CORK OR POLYURETHANE WITH POLYSTYRENE FOAM CLOSURE PLUG NODULES Figure 22. Special Experimental Propelling Charges for 5-In./54</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA123950','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA123950"><span>The Design, Development, and Evaluation of a Differential <span class="hlt">Pressure</span> Gauge Directional <span class="hlt">Wave</span> Monitor.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1982-10-01</p> <p>Ai23 958 THE DESIGN DEVELOPMENT AND EVALUATION OF A DIFFERENTIAL 1/3 <span class="hlt">PRESSURE</span> GURGE DI..(U) COASTRL ENGINEERING RESEARCH CENTER FORT BELVOIR YR K R...I1IBI =. 5 6 LA 112 MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU OF STANDARDS-1963- A q.. MR 82-11 k0- The Design, Development, and Evaluation of a ...OF REPORT & PERIOD COVERED THE DESIGN, DEVELOPMENT, AND EVALUATION Miscellaneous Report OF A DIFFERENTIAL <span class="hlt">PRESSURE</span> GAUGE DIRECTIONAL <span class="hlt">WAVE</span> MONITOR 6</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002EGSGA..27.1349K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002EGSGA..27.1349K"><span>Stratospheric Annular Modes <span class="hlt">Induced</span> By Stationary <span class="hlt">Wave</span> Forcing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Körnich, H.; Schmitz, G.</p> <p></p> <p>The variability of the winter stratosphere shows distinguishable features in the north- ern and southern hemisphere. Since these differences are based on the different plan- etary <span class="hlt">waves</span> of the underlying atmosphere, we explore the mechanism how stationary <span class="hlt">wave</span> forcing in the troposphere can <span class="hlt">induce</span> a stratospheric Annular Mode using a simple GCM. The model KMCM (Kühlungsborn Mechanistic Circulation Model) extends from the ground up to 60 km height and produces a reasonable winter climate. It takes into account the different large-scale <span class="hlt">wave</span> forcings in the troposphere as prescribed pro- cesses. This allows us to examine the stratospheric Annular-Mode generation depend- ing on different <span class="hlt">wave</span> forcings under perpetual January conditions. Principal com- ponent analysis is applied to identify the variability patterns of the geopotential and of the zonally averaged zonal wind. By this way, it is shown that the amplitude and composition of the orographic and thermal eddy forcing determines the stratospheric Annular Mode and the related downward propagation in the temperature field. Further model simplifications are introduced in order to understand the mechanism of the stratospheric AM-generation. Using a linear model version we illuminate the influence of the different <span class="hlt">wave</span> forcing processes on the Annular Modes. Addition- ally, a constant-troposphere model is used to clarify the importance of transient and stationary <span class="hlt">waves</span>. Finally, the Annular Mode is interpreted in terms of the dynamical coupling of the troposphere and stratosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhPl...24d3510L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhPl...24d3510L"><span>Intensity improvement of shock <span class="hlt">waves</span> <span class="hlt">induced</span> by liquid electrical discharges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Yi; Li, Zhi-Yuan; Li, Xian-Dong; Liu, Si-Wei; Zhou, Gu-Yue; Lin, Fu-Chang</p> <p>2017-04-01</p> <p>When shock <span class="hlt">waves</span> <span class="hlt">induced</span> by pulsed electrical discharges in dielectric liquids are widely applied in industrial fields, it is necessary to improve the energy transfer efficiency from electrical energy to mechanical energy to improve the shock <span class="hlt">wave</span> intensity. In order to investigate the effect of the plasma channel length created by the liquid electrical discharge on the shock <span class="hlt">wave</span> intensity, a test stand of dielectric liquid pulsed electrical discharge is designed and constructed. The main capacitor is 3 μF, and the charging voltage is 0-30 kV. Based on the needle-needle electrode geometry with different gap distances, the intensities of shock <span class="hlt">waves</span> corresponding to the electrical parameters, the relationship between the plasma channel length and the deposited energy, and the time-resolved observation of the plasma channel development by a high speed camera are presented and compared. The shock <span class="hlt">wave</span> intensity is closely related to the power and energy dissipated into the plasma channel. The longer plasma channel and the quicker arc expansion can lead to a higher power and energy deposited into the plasma channel, which can activate a stronger shock <span class="hlt">wave</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992cfd..proc..119O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992cfd..proc..119O"><span>Unsteady non-equilibrium model of laser <span class="hlt">induced</span> detonation <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oshima, Takeharu; Fujiwara, Toshitaka</p> <p>1992-12-01</p> <p>Now that laser propulsion is hoped to become a next-generation space propulsion system, it is important to analyze the mechanisms of LSD (Laser-Supported Detonation) <span class="hlt">wave</span> caused by laser absorption. The performance of laser propulsion is determined mainly by laser absorption efficiency. To absorb laser energy effectively, it is necessary to generate sufficient free electrons in the laser absorbing zone. Thus, the LSD <span class="hlt">wave</span> must be monitored. At first, the incident laser energy vaporizes the solid propellant and produces free electrons. These free electrons start laser absorption and as a result produce high temperature and <span class="hlt">pressure</span>. Then an ignition occurs and this grows into a detonation <span class="hlt">wave</span>. Four types of physico-chemical processes take place in the LSD <span class="hlt">wave</span>. First, laser energy is first absorbed by free electrons through inverse bremsstrahlung. Next this energy is distributed to heavy particles (atoms and ions) through elastic and inelastic collision processes, and is lost partly by bremsstrahlung as radiation energy. Based on such backgrounds, this LSD <span class="hlt">wave</span> is simulated by using a plane one-dimensional numerical analysis to clarify the mechanism on the ignition phenomenon in a laser-sustained plasma. In this study, a TVD (Total Variation Diminishing) code which takes account of real gas effects is utilized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760039151&hterms=Seismic+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSeismic%2Bwaves','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760039151&hterms=Seismic+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSeismic%2Bwaves"><span>The effects of <span class="hlt">pressure</span>, temperature, and pore water on velocities in Westerly granite. [for seismic <span class="hlt">wave</span> propagation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Spencer, J. W., Jr.; Nur, A. M.</p> <p>1976-01-01</p> <p>A description is presented of an experimental assembly which has been developed to conduct concurrent measurements of compressional and shear <span class="hlt">wave</span> velocities in rocks at high temperatures and confining <span class="hlt">pressures</span> and with independent control of the pore <span class="hlt">pressure</span>. The apparatus was used in studies of the joint effects of temperature, external confining <span class="hlt">pressure</span>, and internal pore water on sonic velocities in Westerly granite. It was found that at a given temperature, confining <span class="hlt">pressure</span> has a larger accelerating effect on compressional <span class="hlt">waves</span> in dry rock, whereas at a given confining <span class="hlt">pressure</span>, temperature has a larger retarding effect on shear <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhLA..378.2866A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhLA..378.2866A"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> breather overturning on deep water: Exact solution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abrashkin, A. A.; Oshmarina, O. E.</p> <p>2014-08-01</p> <p>A vortical model of breather overturning on deep water is proposed. The action of wind is simulated by nonuniform <span class="hlt">pressure</span> on the free surface. The fluid motion is described by an exact solution of 2D hydrodynamic equations for an inviscid fluid in Lagrangian variables. Fluid particles rotate in circles of different radii. Formation of contraflexure points on the breather profile is studied. The mechanism of <span class="hlt">wave</span> breaking and the role of flow vorticity are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ApPhL.100m3702H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ApPhL.100m3702H"><span>Shear <span class="hlt">wave</span> <span class="hlt">induced</span> resonance elastography of spherical masses with polarized torsional <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hadj Henni, Anis; Schmitt, Cédric; Trop, Isabelle; Cloutier, Guy</p> <p>2012-03-01</p> <p>Shear <span class="hlt">wave</span> <span class="hlt">induced</span> resonance (SWIR) is a technique for dynamic ultrasound elastography of confined mechanical inclusions. It was developed for breast tumor imaging and tissue characterization. This method relies on the polarization of torsional shear <span class="hlt">waves</span> modeled with the Helmholtz equation in spherical coordinates. To validate modeling, an invitro set-up was used to measure and image the first three eigenfrequencies and eigenmodes of a soft sphere. A preliminary invivo SWIR measurement on a breast fibroadenoma is also reported. Results revealed the potential of SWIR elastography to detect and mechanically characterize breast lesions for early cancer detection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17282491','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17282491"><span>Energy Transform and Initial Acoustic <span class="hlt">Pressure</span> Distribution in Microwave-<span class="hlt">induced</span> Thermoacoustic Tomography.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yan, Jing; Tao, Chunjing; Wu, Shizeng</p> <p>2005-01-01</p> <p>A study of Microwave-<span class="hlt">induced</span> Thermoacoustic Tomography is presented in this paper. Microwaves illuminate biological tissues to generate acoustic <span class="hlt">waves</span> by thermoelastic expansion when electromagnetic energy was absorbed by human tissues. The generated acoustic <span class="hlt">waves</span> carry information about different electromagnetic properties of different tissues which will be collected and processed to reconstruct human cross section image. In this paper, digital electromagnetic human body model with 1cm resolution was founded according to algorithm requirements. Firstly we analyzed the transform and interrelation among electromagnetic energy, heat energy and acoustic energy. On the basis of established human model: (1) we calculated initial acoustic <span class="hlt">pressure</span> distribution in cross section image under plane microwave radiation with different frequency. It shows that microwave absorption properties and initial acoustic <span class="hlt">pressure</span> were different with the change of frequency; (2) using single pulse to illuminate human model, initial acoustic <span class="hlt">pressure</span> maps of thorax cross section at different time steps were analyzed. These results provided a research basis for further study and calculation of acoustic <span class="hlt">pressure</span> in microwave-<span class="hlt">induced</span> thermoacoustic tomography.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPC.1689e0005V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPC.1689e0005V"><span><span class="hlt">Wave</span> <span class="hlt">induced</span> density modification in RF sheaths and close to <span class="hlt">wave</span> launchers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Van Eester, D.; Crombé, K.; Lu, Ling-Feng</p> <p>2015-12-01</p> <p>With the return to full metal walls - a necessary step towards viable fusion machines - and due to the high power densities of current-day ICRH (Ion Cyclotron Resonance Heating) or RF (radio frequency) antennas, there is ample renewed interest in exploring the reasons for <span class="hlt">wave-induced</span> sputtering and formation of hot spots. Moreover, there is experimental evidence on various machines that RF <span class="hlt">waves</span> influence the density profile close to the <span class="hlt">wave</span> launchers so that <span class="hlt">waves</span> indirectly influence their own coupling efficiency. The present study presents a return to first principles and describes the <span class="hlt">wave</span>-particle interaction using a 2-time scale model involving the equation of motion, the continuity equation and the <span class="hlt">wave</span> equation on each of the time scales. Through the changing density pattern, the fast time scale dynamics is affected by the slow time scale events. In turn, the slow time scale density and flows are modified by the presence of the RF <span class="hlt">waves</span> through quasilinear terms. Although finite zero order flows are identified, the usual cold plasma dielectric tensor - ignoring such flows - is adopted as a first approximation to describe the <span class="hlt">wave</span> response to the RF driver. The resulting set of equations is composed of linear and nonlinear equations and is tackled in 1D in the present paper. Whereas the former can be solved using standard numerical techniques, the latter require special handling. At the price of multiple iterations, a simple 'derivative switch-on' procedure allows to reformulate the nonlinear problem as a sequence of linear problems. Analytical expressions allow a first crude assessment - revealing that the ponderomotive potential plays a role similar to that of the electrostatic potential arising from charge separation - but numerical implementation is required to get a feeling of the full dynamics. A few tentative examples are provided to illustrate the phenomena involved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22496198','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22496198"><span><span class="hlt">Wave</span> <span class="hlt">induced</span> density modification in RF sheaths and close to <span class="hlt">wave</span> launchers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Van Eester, D.; Lu, Ling-Feng</p> <p>2015-12-10</p> <p>With the return to full metal walls - a necessary step towards viable fusion machines - and due to the high power densities of current-day ICRH (Ion Cyclotron Resonance Heating) or RF (radio frequency) antennas, there is ample renewed interest in exploring the reasons for <span class="hlt">wave-induced</span> sputtering and formation of hot spots. Moreover, there is experimental evidence on various machines that RF <span class="hlt">waves</span> influence the density profile close to the <span class="hlt">wave</span> launchers so that <span class="hlt">waves</span> indirectly influence their own coupling efficiency. The present study presents a return to first principles and describes the <span class="hlt">wave</span>-particle interaction using a 2-time scale model involving the equation of motion, the continuity equation and the <span class="hlt">wave</span> equation on each of the time scales. Through the changing density pattern, the fast time scale dynamics is affected by the slow time scale events. In turn, the slow time scale density and flows are modified by the presence of the RF <span class="hlt">waves</span> through quasilinear terms. Although finite zero order flows are identified, the usual cold plasma dielectric tensor - ignoring such flows - is adopted as a first approximation to describe the <span class="hlt">wave</span> response to the RF driver. The resulting set of equations is composed of linear and nonlinear equations and is tackled in 1D in the present paper. Whereas the former can be solved using standard numerical techniques, the latter require special handling. At the price of multiple iterations, a simple ’derivative switch-on’ procedure allows to reformulate the nonlinear problem as a sequence of linear problems. Analytical expressions allow a first crude assessment - revealing that the ponderomotive potential plays a role similar to that of the electrostatic potential arising from charge separation - but numerical implementation is required to get a feeling of the full dynamics. A few tentative examples are provided to illustrate the phenomena involved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003ASAJ..114R2465M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003ASAJ..114R2465M"><span>Shock <span class="hlt">wave</span> <span class="hlt">induced</span> sonoporation and gene transfer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Miller, Douglas L.</p> <p>2003-10-01</p> <p>During shockwave (SW) treatment, cavitation activity can be applied for cell killing. A bonus is that some surviving cells appear to be briefly permeabilized, or sonoporated, allowing them to take up large molecules including DNA. In vitro research has indicated that as the number of SW increased, survival declined exponentially but the number of sonoporated cells increased to better than 50% of survivors for 1000 SW. In vivo tests have demonstrated SW-<span class="hlt">induced</span> tumor ablation could indeed be accompanied by the transfection of marker plasmids into mouse B16 melanoma tumors in vivo. With intratumor injection of plasmid DNA and air bubbles, significant results were obtained for only 400 SW. In a trial of cancer therapy, the effects of 500 SW combined with interleukin-12 immuno-gene therapy was observed on the progression of two mouse tumors, B16 melanoma and RENCA renal carcinoma. The combination of SW and IL-12 plasmid injection provided a statistically significant inhibition of tumor growth relative to SW alone for both tumor models, demonstrating feasibility for this treatment method. In the future, the development of intravenous gene delivery and improved transfection, together with image-guided ultrasound treatment, should lead to the clinical application of ultrasound enhanced gene therapy. [Work supported by NIH Grant No. EB002782.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SSSci..48...49L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SSSci..48...49L"><span><span class="hlt">Pressure-induced</span> structural phase transition, elastic and thermodynamic properties of ReC under high <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lei, Hui-Ru; Zhu, Jun; Hao, Yan-Jun; Zhang, Lin; Zhao, Yu-Xin; Zhan, Guo-Fu</p> <p>2015-10-01</p> <p>The <span class="hlt">pressure-induced</span> structural phase transition of rhenium monocarbon (ReC) is investigated via the projector augmented <span class="hlt">wave</span> (PAW) method with the generalized gradient approximation (GGA). Using the first-principles calculations, the equilibrium structural parameters of ReC in rocksalt (NaCl), cesium chloride (CsCl), zinc blende (ZB), wurtzite (WZ), nickel arsenide (NiAs) and tungsten carbide (WC) types are successfully obtained, and the results are well consistent with other theoretical data. It is firstly noted that WC-ReC translates into CsCl-ReC at 510.50 GPa by analyzing the enthalpy difference versus <span class="hlt">pressure</span>. From the calculated elastic constants, the aggregate elastic modulus (B, G, E), the Poisson's ratio (σ) and the Debye temperature ΘD of WC-type are also derived. It is observed that all the data of WC-ReC obtained increase monotonically with increasing <span class="hlt">pressure</span>. Meanwhile, the thermodynamic properties of WC-ReC under high temperature and high <span class="hlt">pressure</span> are investigated applying nonempirical Debye model in the quasi-harmonic approximation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3404643','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3404643"><span>Increasing pulse <span class="hlt">wave</span> velocity in a realistic cardiovascular model does not increase pulse <span class="hlt">pressure</span> with age</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mohiuddin, Mohammad W.; Rihani, Ryan J.; Laine, Glen A.</p> <p>2012-01-01</p> <p>The mechanism of the well-documented increase in aortic pulse <span class="hlt">pressure</span> (PP) with age is disputed. Investigators assuming a classical windkessel model believe that increases in PP arise from decreases in total arterial compliance (Ctot) and increases in total peripheral resistance (Rtot) with age. Investigators assuming a more sophisticated pulse transmission model believe PP rises because increases in pulse <span class="hlt">wave</span> velocity (cph) make the reflected <span class="hlt">pressure</span> <span class="hlt">wave</span> arrive earlier, augmenting systolic <span class="hlt">pressure</span>. It has recently been shown, however, that increases in cph do not have a commensurate effect on the timing of the reflected <span class="hlt">wave</span>. We therefore used a validated, large-scale, human arterial system model that includes realistic pulse <span class="hlt">wave</span> transmission to determine whether increases in cph cause increased PP with age. First, we made the realistic arterial system model age dependent by altering cardiac output (CO), Rtot, Ctot, and cph to mimic the reported changes in these parameters from age 30 to 70. Then, cph was theoretically maintained constant, while Ctot, Rtot, and CO were altered. The predicted increase in PP with age was similar to the observed increase in PP. In a complementary approach, Ctot, Rtot, and CO were theoretically maintained constant, and cph was increased. The predicted increase in PP was negligible. We found that increases in cph have a limited effect on the timing of the reflected <span class="hlt">wave</span> but cause the system to degenerate into a windkessel. Changes in PP can therefore be attributed to a decrease in Ctot. PMID:22561301</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21538207','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21538207"><span>Enhancement of airborne shock <span class="hlt">wave</span> by laser-<span class="hlt">induced</span> breakdown of liquid column in laser shock cleaning</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Jang, Deoksuk; Kim, Dongsik; Park, Jin-Goo</p> <p>2011-04-01</p> <p>In laser shock cleaning (LSC), the shock <span class="hlt">wave</span> is generated by laser-<span class="hlt">induced</span> breakdown of the ambient gas. The shock <span class="hlt">wave</span> intensity has thus been a factor limiting the performance of the LSC process. In this work, a novel method of amplifying a laser-<span class="hlt">induced</span> plasma-generated shock <span class="hlt">wave</span> by the breakdown of a liquid column is proposed and analyzed. When the laser beam is focused on a microscale liquid column, a shock <span class="hlt">wave</span> having a significantly amplified intensity compared to that generated by air breakdown alone can be generated in air. Therefore, substantially amplified cleaning force can be obtained. The dynamics of a shock <span class="hlt">wave</span> <span class="hlt">induced</span> by a Q-switched Nd:YAG laser was analyzed by laser flash shadowgraphy. The peak <span class="hlt">pressure</span> of the laser-<span class="hlt">induced</span> shock <span class="hlt">wave</span> was approximately two times greater than that of air breakdown at the same laser fluence. The proposed method of shock <span class="hlt">wave</span> generation is expected to be useful in various applications of laser shock processing, including surface cleaning.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19960009427','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19960009427"><span>Control and reduction of unsteady <span class="hlt">pressure</span> loads in separated shock <span class="hlt">wave</span> turbulent boundary layer interaction</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dolling, David S.; Barter, John W.</p> <p>1995-01-01</p> <p>The focus was on developing means of controlling and reducing unsteady <span class="hlt">pressure</span> loads in separated shock <span class="hlt">wave</span> turbulent boundary layer interactions. Section 1 describes how vortex generators can be used to effectively reduce loads in compression ramp interaction, while Section 2 focuses on the effects of 'boundary-layer separators' on the same interaction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014OEng....4..110G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014OEng....4..110G"><span>Internal combustion engine supercharging: turbocharger vs. <span class="hlt">pressure</span> <span class="hlt">wave</span> compressor. Performance comparison</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>George, Atanasiu; Chiru, Anghel</p> <p>2014-06-01</p> <p>This paper aims on comparison between a turbocharged engine and a <span class="hlt">pressure</span> <span class="hlt">wave</span> charged engine. The comparison was accomplished using the engine simulation software AVL Boost, version 2010. The grahps were extracted using AVL Impress, version 2010. The performance increase is limited by the mechanical side of the simulated engine.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhDT.......242C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhDT.......242C"><span><span class="hlt">Pressure</span> fluctuations beneath instability <span class="hlt">wave</span> packets and turbulent spots in a hypersonic boundary layer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Casper, Katya M.</p> <p></p> <p>During atmospheric reentry, hypersonic vehicles are subjected to high levels of boundary-layer <span class="hlt">pressure</span> fluctuations that cause vibration of internal components. Current models are not adequate to predict these fluctuations. A more physics-based approach can be obtained by using a turbulent-spot model of transition. In order to gain a better understanding of the <span class="hlt">pressure</span>-fluctuation field and the growth of turbulent spots in a hypersonic boundary layer, the development of disturbances was studied on the nozzle wall of the Boeing/AFOSR Mach-6 Quiet Tunnel. Under quiet flow conditions, the nozzle wall boundary layer remains laminar and grows very thick over the long nozzle length. This allows the development of large disturbances that can be well-resolved with high-frequency <span class="hlt">pressure</span> transducers. For a controlled study, disturbances were created by pulsed glow perturbations and studied at various freestream conditions. Both the centerline and the spanwise distribution of <span class="hlt">pressure</span> fluctuations were measured as boundary-layer disturbances grew from linear instability <span class="hlt">wave</span> packets into turbulent spots. A disturbance first grows into a linear instability <span class="hlt">wave</span> packet and then quickly becomes nonlinear. At this point, the <span class="hlt">wave</span> packet is still concentrated near the disturbance centerline, but weaker disturbances are seen spreading from the center. Throughout the nonlinear growth of the <span class="hlt">wave</span> packets, large harmonics are visible in the power spectra. Breakdown to turbulence begins in the core of the <span class="hlt">wave</span> packets where the <span class="hlt">wave</span> amplitudes are largest. As breakdown begins, the peak amplitudes of the instability <span class="hlt">waves</span> and harmonics decrease into the rising broadband frequencies. Second-mode <span class="hlt">waves</span> are still evident in front of and behind the breakdown point and can be seen propagating in the spanwise direction at a spreading angle. The turbulent core grows downstream, resulting in a turbulent spot with a typical arrowhead shape. However, the spot is not merely a localized patch</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...848L...1R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...848L...1R"><span>On the Chemical Mixing <span class="hlt">Induced</span> by Internal Gravity <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rogers, T. M.; McElwaine, J. N.</p> <p>2017-10-01</p> <p>Detailed modeling of stellar evolution requires a better understanding of the (magneto)hydrodynamic processes that mix chemical elements and transport angular momentum. Understanding these processes is crucial if we are to accurately interpret observations of chemical abundance anomalies, surface rotation measurements, and asteroseismic data. Here, we use two-dimensional hydrodynamic simulations of the generation and propagation of internal gravity <span class="hlt">waves</span> in an intermediate-mass star to measure the chemical mixing <span class="hlt">induced</span> by these <span class="hlt">waves</span>. We show that such mixing can generally be treated as a diffusive process. We then show that the local diffusion coefficient does not depend on the local fluid velocity, but rather on the <span class="hlt">wave</span> amplitude. We then use these findings to provide a simple parameterization for this diffusion, which can be incorporated into stellar evolution codes and tested against observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PPNL...12..389D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PPNL...12..389D"><span>Hydrodynamic <span class="hlt">pressure</span> computation under real sea surface on basis of autoregressive model of irregular <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Degtyarev, A.; Gankevich, I.</p> <p>2015-05-01</p> <p>Determining the impact of external excitations on a dynamic marine object such as ship hull in a seaway is the main goal of simulations. Now such simulations is most often based on approximate mathematical models that use results of the theory of small amplitude <span class="hlt">waves</span>. The most complicated software for marine objects behavior simulation LAMP IV (Large amplitude motion program) uses numerical solution of traditional hydrodynamic problem without often used approximations but on the basis of theory of small amplitude <span class="hlt">waves</span>. For efficiency reasons these simulations can be based on autoregressive model to generate real <span class="hlt">wave</span> surface. Such a surface possesses all the hydrodynamic characteristics of sea <span class="hlt">waves</span>, preserves dispersion relation and also shows superior performance compared to other wind <span class="hlt">wave</span> models. Naturally, the known surface can be used to compute velocity field and in turn to determine <span class="hlt">pressures</span> in any point under sea surface. The resulting computational algorithm can be used to determine <span class="hlt">pressures</span> without use of theory of small-amplitude <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/476630','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/476630"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> phase transitions in ceramic compounds containing tetragonal zirconia</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sparks, R.G.; Pfeiffer, G.; Paesler, M.A.</p> <p>1988-12-01</p> <p>Stabilized tetragonal zirconia compounds exhibit a transformation toughening process in which stress applied to the material <span class="hlt">induces</span> a crystallographic phase transition. The phase transition is accompanied by a volume expansion in the stressed region thereby dissipating stress and increasing the fracture strength of the material. The hydrostatic component of the stress required to <span class="hlt">induce</span> the phase transition can be investigated by the use of a high <span class="hlt">pressure</span> technique in combination with Micro-Raman spectroscopy. The intensity of Raman lines characteristic for the crystallographic phases can be used to calculate the amount of material that has undergone the transition as a function of <span class="hlt">pressure</span>. It was found that <span class="hlt">pressures</span> on the order of 2-5 kBar were sufficient to produce an almost complete transition from the original tetragonal to the less dense monoclinic phase; while a further increase in <span class="hlt">pressure</span> caused a gradual reversal of the transition back to the original tetragonal structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/8987273','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/8987273"><span>Linear hydraulic <span class="hlt">pressure</span>-pulse actuator (LHPA): a versatile instrument that produces a simulated blood <span class="hlt">pressure</span> pulse <span class="hlt">wave</span> for small sized vessels.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Field, S; Drzewiecki, G</p> <p>1996-06-01</p> <p>An instrument is presented which produces a simulated circulatory pulsatile <span class="hlt">pressure</span> <span class="hlt">wave</span> for small sized vessels. The linear hydraulic <span class="hlt">pressure</span>-pulse actuator (LHPA) is designed to be extremely versatile, that is, a blood <span class="hlt">pressure</span> <span class="hlt">wave</span> source of any shape, amplitude, offset and frequency can be simulated. In addition, the LHPA can reproduce accurately a real pulse <span class="hlt">pressure</span> <span class="hlt">wave</span> by simply imputting an actual data record of a circulatory <span class="hlt">pressure</span> pulse. The design is accomplished by incorporating the use of a linear force solenoid driven with a voltage-to-current source power amplifier. Testing of the device is presented here, as well as <span class="hlt">pressure</span> pulse results from a recorded pulsatile <span class="hlt">pressure</span> input to the LHPA. The device is simple to implement in that its response is linear, for volume changes upto +/- 5 mL, without the need for feedback compensation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5338774','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5338774"><span>Amplified-response-spectrum analysis of sodium-water reaction <span class="hlt">pressure</span> <span class="hlt">waves</span>. [LMFBR</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Knittle, D.E.</p> <p>1981-10-28</p> <p>This report deals with a frequency spectrum evaluation of the SWAAM I predicted double rupture disc assembly operation <span class="hlt">pressure</span> <span class="hlt">wave</span> generated in the LLTR Series II A-2 test. It also evaluates the same <span class="hlt">wave</span> predicted by the TRANSWRAP II code and the <span class="hlt">pressure</span> <span class="hlt">wave</span> actually measured upstream of the rupture disc assembly by the test instrumentation in Test A-2. The SWAAM I and TRANSWRAP II codes currently use the same analytical model to characterize the rupture disc until the disc strikes the knife edges. Thereafter, the SWAAM I code relies on analytical techniques to characterize the phenomena, whereas the TRANSWRAP II code uses empirical parameters based on A-2 test data to represent the disc behavior. Any differences in the predicted dynamic pipe loads caused by double rupture disc assembly operation, using the forcing functions predicted by the codes can, therefore, be traced to this difference.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JaJAP..55gKF13M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JaJAP..55gKF13M"><span>Three-dimensional visualization of shear <span class="hlt">wave</span> propagation generated by dual acoustic radiation <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mochizuki, Yuta; Taki, Hirofumi; Kanai, Hiroshi</p> <p>2016-07-01</p> <p>An elastic property of biological soft tissue is an important indicator of the tissue status. Therefore, quantitative and noninvasive methods for elasticity evaluation have been proposed. Our group previously proposed a method using acoustic radiation <span class="hlt">pressure</span> irradiated from two directions for elastic property evaluation, in which by measuring the propagation velocity of the shear <span class="hlt">wave</span> generated by the acoustic radiation <span class="hlt">pressure</span> inside the object, the elastic properties of the object were successfully evaluated. In the present study, we visualized the propagation of the shear <span class="hlt">wave</span> in a three-dimensional space by the synchronization of signals received at various probe positions. The proposed method succeeded in visualizing the shear <span class="hlt">wave</span> propagation clearly in the three-dimensional space of 35 × 41 × 4 mm3. These results show the high potential of the proposed method to estimate the elastic properties of the object in the three-dimensional space.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22257111','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22257111"><span>Effect of the dynamic <span class="hlt">pressure</span> on the shock <span class="hlt">wave</span> structure in a rarefied polyatomic gas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Taniguchi, Shigeru Sugiyama, Masaru; Arima, Takashi; Ruggeri, Tommaso</p> <p>2014-01-15</p> <p>We study the shock <span class="hlt">wave</span> structure in a rarefied polyatomic gas based on a simplified model of extended thermodynamics in which the dissipation is due only to the dynamic <span class="hlt">pressure</span>. In this case the differential system is very simple because it is a variant of Euler system with a new scalar equation for the dynamic <span class="hlt">pressure</span> [T. Arima, S. Taniguchi, T. Ruggeri, and M. Sugiyama, Phys. Lett. A 376, 2799–2803 (2012)]. It is shown that this theory is able to describe the three types of the shock <span class="hlt">wave</span> structure observed in experiments: the nearly symmetric shock <span class="hlt">wave</span> structure (Type A, small Mach number), the asymmetric structure (Type B, moderate Mach number), and the structure composed of thin and thick layers (Type C, large Mach number)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1007733','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1007733"><span>Radiation-<span class="hlt">induced</span> decomposition of PETN and TATB under <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Giefers, Hubertus; Pravica, Michael; Liermann, Hanns-Peter; Yang, Wenge</p> <p>2008-10-02</p> <p>We have investigated decomposition of PETN and TATB <span class="hlt">induced</span> by white synchrotron X-ray radiation in a diamond anvil cell at ambient temperature and two <span class="hlt">pressures</span>, nearly ambient and about 6 GPa. The decomposition rate of TATB decreases significantly when it is <span class="hlt">pressurized</span> to 5.9 GPa. The measurements were highly reproducible and allowed us to obtain decomposition rates and the order parameters of the reactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/7571133','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/7571133"><span>Thresholds for hemorrhages in mouse skin and intestine <span class="hlt">induced</span> by lithotripter shock <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Miller, D L; Thomas, R M</p> <p>1995-01-01</p> <p>In vivo biological effects of ultrasound should be characterized as thermal or cavitational to understand their etiology and significance. A spark-gap shock-<span class="hlt">wave</span> lithotripter was built and used to compare cavitation-<span class="hlt">induced</span> hemorrhages to the heat-<span class="hlt">induced</span> petechial hemorrhages caused by continuous-<span class="hlt">wave</span> ultrasound in mouse intestine. Intestinal hemorrhages <span class="hlt">induced</span> in anesthetized hairless mice by the lithotripter pulses involved tissue destruction with bleeding into the lumen of the intestine, and were associated with intestinal gas bubbles. Skin hemorrhages were also observed, which appeared to be contusions, with no actual breakage of the skin. Administration of 100 shock <span class="hlt">waves</span> with peak positive amplitude of 18.5 MPa produced an average of 7.6 (standard error [SE] 3.1, n = 6) intestinal hemorrhages and 45 (SE 11) skin hemorrhages. The counts and severity of hemorrhages increased with increasing numbers (3 to 300) of shock <span class="hlt">waves</span>. Absorbers of varying thickness were used to reduce the <span class="hlt">pressure</span> amplitude of the shock <span class="hlt">waves</span>, which were thereby modified into low frequency ultrasound pulses. For 100 pulse exposures, apparent thresholds for effects occurred between 1.6 and 4.0 MPa for the intestinal hemorrhages and between 0.6 and 1.6 MPa for the skin hemorrhages. The low 1-Hz pulse repetition frequency precluded significant heating, and so these effects were the result of cavitation, which probably occurred inside the intestines or in the surrounding water. Compared to the previously observed thermal petechia, the cavitation-<span class="hlt">induced</span> hemorrhages could be distinguished on the basis of their appearance upon histological examination, and also by the relative values of the thermal and mechanical exposure indices associated with the two different exposure modes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1056357','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1056357"><span>On the Toroidal Plasma Rotations <span class="hlt">Induced</span> by Lower Hybrid <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Guan, Xiaoyin; Qin, Hong; Liu, Jian; Fisch, Nathaniel J.</p> <p>2012-11-14</p> <p>A theoretical model is developed to explain the plasma rotations <span class="hlt">induced</span> by lower hybrid <span class="hlt">waves</span> in Alcator C-Mod. In this model, torodial rotations are driven by the Lorentz force on the bulk electron flow across flux surfaces, which is a response of the plasma to the resonant-electron flow across flux surfaces <span class="hlt">induced</span> by the lower hybrid <span class="hlt">waves</span>. The flow across flux surfaces of the resonant electrons and the bulk electrons are coupled through the radial electric fi eld initiated by the resonant electrons, and the friction between ions and electrons transfers the toroidal momentum to ions from electrons. An improved quasilinear theory with gyrophase dependent distribution function is developed to calculate the perpendicular resonant-electron flow. Toroidal rotations are determined using a set of fluid equations for bulk electrons and ions, which are solved numerically by a fi nite- difference method. Numerical results agree well with the experimental observations in terms of flow pro file and amplitude. The model explains the strong correlation between torodial flow and internal inductance observed experimentally, and predicts both counter-current and co-current flows, depending on the perpendicular <span class="hlt">wave</span> vectors of the lower hybrid <span class="hlt">waves</span>. __________________________________________________</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvA..94b3604C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvA..94b3604C"><span>Ballistic quench-<span class="hlt">induced</span> correlation <span class="hlt">waves</span> in ultracold gases</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Corson, John P.; Bohn, John L.</p> <p>2016-08-01</p> <p>We investigate the <span class="hlt">wave</span>-packet dynamics of a pair of particles that undergoes a rapid change of scattering length. The short-range interactions are modeled in the zero-range limit, where the quench is accomplished by switching the boundary condition of the <span class="hlt">wave</span> function at vanishing particle separation. This generates a correlation <span class="hlt">wave</span> that propagates rapidly to nonzero particle separations. We have derived universal, analytic results for this process that lead to a simple phase-space picture of the quench-<span class="hlt">induced</span> scattering. Intuitively, the strength of the correlation <span class="hlt">wave</span> relates to the initial contact of the system. We find that, in one spatial dimension, the k-4 tail of the momentum distribution contains a ballistic contribution that does not originate from short-range pair correlations, and a similar conclusion can hold in other dimensionalities depending on the quench protocol. We examine the resultant quench-<span class="hlt">induced</span> transport in an optical lattice in one dimension, and a semiclassical treatment is found to give quantitatively accurate estimates for the transport probabilities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.710a2031S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.710a2031S"><span>Experimental Study on a Standing <span class="hlt">Wave</span> Thermoacoustic Prime Mover with Air Working Gas at Various <span class="hlt">Pressures</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Setiawan, Ikhsan; Achmadin, Wahyu N.; Murti, Prastowo; Nohtomi, Makoto</p> <p>2016-04-01</p> <p>Thermoacoustic prime mover is an energy conversion device which converts thermal energy into acoustic work (sound <span class="hlt">wave</span>). The advantages of this machine are that it can work with air as the working gas and does not produce any exhaust gases, so that it is environmentally friendly. This paper describes an experimental study on a standing <span class="hlt">wave</span> thermoacoustic prime mover with air as the working gas at various <span class="hlt">pressures</span> from 0.05 MPa to 0.6 MPa. We found that 0.2 MPa is the optimum <span class="hlt">pressure</span> which gives the lowest onset temperature difference of 355 °C. This <span class="hlt">pressure</span> value would be more preferable in harnessing low grade heat sources to power the thermoacoustic prime mover. In addition, we find that the lowest onset temperature difference is obtained when rh /δ k ratio is 2.85, where r h is the hydraulic radius of the stack and δ k is the thermal penetration depth of the gas. Moreover, the <span class="hlt">pressure</span> amplitude of the sound <span class="hlt">wave</span> is significantly getting larger from 2.0 kPa to 9.0 kPa as the charged <span class="hlt">pressure</span> increases from 0.05 MPa up to 0.6 MPa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26112919','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26112919"><span>Effect of moderate exercise-<span class="hlt">induced</span> heat stress on carotid <span class="hlt">wave</span> intensity.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Smith, Denise L; DeBlois, Jacob P; Wharton, Margaret; Fehling, Patricia C; Ranadive, Sushant M</p> <p>2015-10-01</p> <p>Exercise disrupts the interaction between the left ventricle and the vasculature, as measured by <span class="hlt">wave</span> intensity (WI) analysis. However, the effect of exercise-<span class="hlt">induced</span> heat stress on WI amplitude is unknown. WI measures are calibrated using brachial or carotid artery blood <span class="hlt">pressure</span>, but the influence of calibration method on WI outcomes is unknown. (1) To compare WI analysis during low and moderate exercise-<span class="hlt">induced</span> heat stress; (2) to examine differences in carotid WI analysis based on calibration method. Eleven healthy, young men (22 ± 3 years) performed intermittent exercise in moderate- and low-heat stress conditions. WI was assessed pre- and post-exercise on the right carotid artery, and calibrated with brachial and carotid blood <span class="hlt">pressures</span>. A main effect of time was found for W1 when calibrated by brachial, but not carotid <span class="hlt">pressure</span>. A time-by-condition interaction was observed for late systolic/early diastolic function (W2) in both brachial (p = 0.047) and carotid calibration methods (p = 0.042), where W2 increased following exercise-<span class="hlt">induced</span> moderate-heat stress but decreased following low-heat stress. The elastic modulus exhibited a significant time-by-condition interaction (brachial p = 0.039; carotid p = 0.044), increasing following moderate-heat stress but decreasing following low-heat stress. Calibrations using carotid blood <span class="hlt">pressure</span> significantly reduced WI amplitudes compared with brachial calibrations (p < 0.001). Arterial-ventricular coupling is affected in different ways following moderate and low exercise-<span class="hlt">induced</span> heat stress. <span class="hlt">Wave</span> amplitudes were lower (~13 %) following carotid calibration compared with brachial.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DPPG10140P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DPPG10140P"><span>Agyrotropic <span class="hlt">pressure</span> tensor <span class="hlt">induced</span> by the plasma velocity shear</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pegoraro, Francesco; Del Sarto, Danele; Califano, Francesco</p> <p>2016-10-01</p> <p>We show that the spatial inhomogeneity of a shear flow in a fluid plasma is transferred to a <span class="hlt">pressure</span> anisotropy that has both a gyrotropic and a non gyrotropic component. We investigate this process both analytically and numerically by including the full <span class="hlt">pressure</span> tensor dynamics. We determine the time evolution of the <span class="hlt">pressure</span> agyrotropy and in general of the <span class="hlt">pressure</span> tensor anisotropization which arise from the action of both the magnetic eld and the flow strain tensor. This mechanism can affect the onset and development of shear-<span class="hlt">induced</span> fluid instabilities in plasmas and is relevant to the understanding of the origin of some of the non-Maxwellian distribution functions evidenced both in Vlasov simulations and in space plasma measurements that exhibit <span class="hlt">pressure</span> agyrotropy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19670012652','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19670012652"><span>Investigation to define the propagation characteristics of a finite amplitude acoustic <span class="hlt">pressure</span> <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Peter, A. C.; Cottrell, J. W.</p> <p>1967-01-01</p> <p>A theoretical analysis of the propagation characteristics of a finite amplitude <span class="hlt">pressure</span> <span class="hlt">wave</span> is presented. The analysis attempts to study the contribution of entropy-producing regions to the mechanism of aerodynamic noise generation. It results in a nonlinear convective <span class="hlt">wave</span> equation in terms of entropy and a thermodynamic 'J' function. A direct analogy between the derived governing equation and those used in classical literature is obtained. An idealization of the processes considered permits the uncoupling of the equations of motion with a consequent construction of an acoustic analogy treating shock <span class="hlt">wave</span> emission of finite amplitude acoustic <span class="hlt">waves</span>. An engineering approach is reflected in the concept of an extended plug nozzle whose function is to facilitate aerodynamic noise attenuation by modifying the entropy-producing regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5078616','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5078616"><span>Measurement of the normal component of compressive <span class="hlt">wave</span> <span class="hlt">pressure</span> in a rock with Manganin sensors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Virchenko, V.A.; Egorov, A.P.; Krasavin, S.V.</p> <p>1985-03-01</p> <p>Measurement of dynamic <span class="hlt">pressures</span> in compressed media with manganin wire sensors has become common in the past few years. The increased interest in this method is due to the technological simplicity of measurement and the ease of manufacturing the manganin pickup. The method has been continually improved and put to new applications. In this paper the authors describe an experiment using manganin sensors to measure the normal component of a compressive <span class="hlt">pressure</span> <span class="hlt">wave</span> in rocks (marble, schist, and diabase) generated by industrial blasts. Subtle effects not previously identified include: decomposition of the shockwave in the rock and identification of an elastic precursor; features of damping of the normal component of compressive <span class="hlt">wave</span> <span class="hlt">pressure</span> as a function of distance from the load application point; and the pattern of destruction of brittle materials. The authors conclude that manganin sensors can be broadly applied in mining for studies of the efficacy of various types of explosives and in investigations of the mechanism of rock destruction.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25233859','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25233859"><span>Brachial vs. central systolic <span class="hlt">pressure</span> and pulse <span class="hlt">wave</span> transmission indicators: a critical analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Izzo, Joseph L</p> <p>2014-12-01</p> <p>This critique is intended to provide background for the reader to evaluate the relative clinical utilities of brachial cuff systolic blood <span class="hlt">pressure</span> (SBP) and its derivatives, including pulse <span class="hlt">pressure</span>, central systolic <span class="hlt">pressure</span>, central augmentation index (AI), and pulse <span class="hlt">pressure</span> amplification (PPA). The critical question is whether the newer indicators add sufficient information to justify replacing or augmenting brachial cuff blood <span class="hlt">pressure</span> (BP) data in research and patient care. Historical context, pathophysiology of variations in pulse <span class="hlt">wave</span> transmission and reflection, issues related to measurement and model errors, statistical limitations, and clinical correlations are presented, along with new comparative data. Based on this overview, there is no compelling scientific or practical reason to replace cuff SBP with any of the newer indicators in the vast majority of clinical situations. Supplemental value for central SBP may exist in defining patients with exaggerated PPA ("spurious systolic hypertension"), managing cardiac and aortic diseases, and in studies of cardiovascular drugs, but there are no current standards for these possibilities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17432720','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17432720"><span><span class="hlt">Pressure</span>-dependent effect of shock <span class="hlt">waves</span> on rat brain: induction of neuronal apoptosis mediated by a caspase-dependent pathway.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kato, Kaoruko; Fujimura, Miki; Nakagawa, Atsuhiro; Saito, Atsushi; Ohki, Tomohiro; Takayama, Kazuyoshi; Tominaga, Teiji</p> <p>2007-04-01</p> <p>Shock <span class="hlt">waves</span> have been experimentally applied to various neurosurgical treatments including fragmentation of cerebral emboli, perforation of cyst walls or tissue, and delivery of drugs into cells. Nevertheless, the application of shock <span class="hlt">waves</span> to clinical neurosurgery remains challenging because the threshold for shock <span class="hlt">wave-induced</span> brain injury has not been determined. The authors investigated the <span class="hlt">pressure</span>-dependent effect of shock <span class="hlt">waves</span> on histological changes of rat brain, focusing especially on apoptosis. Adult male rats were exposed to a single shot of shock <span class="hlt">waves</span> (produced by silver azide explosion) at overpressures of 1 or 10 MPa after craniotomy. Histological changes were evaluated sequentially by H & E staining and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL). The expression of active caspase-3 and the effect of the nonselective caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK) were examined to evaluate the contribution of a caspase-dependent pathway to shock <span class="hlt">wave-induced</span> brain injury. High-overpressure (> 10 MPa) shock <span class="hlt">wave</span> exposure resulted in contusional hemorrhage associated with a significant increase in TUNEL-positive neurons exhibiting chromatin condensation, nuclear segmentation, and apoptotic bodies. The maximum increase was seen at 24 hours after shock <span class="hlt">wave</span> application. Low-overpressure (1 MPa) shock <span class="hlt">wave</span> exposure resulted in spindle-shaped changes in neurons and elongation of nuclei without marked neuronal injury. The administration of Z-VAD-FMK significantly reduced the number of TUNEL-positive cells observed 24 hours after high-overpressure shock <span class="hlt">wave</span> exposure (p < 0.01). A significant increase in the cytosolic expression of active caspase-3 was evident 24 hours after high-overpressure shock <span class="hlt">wave</span> application; this increase was prevented by Z-VAD-FMK administration. Double immunofluorescence staining showed that TUNEL-positive cells were exclusively neurons. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017BrJPh..47...42J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017BrJPh..47...42J"><span>First-Principles Study of <span class="hlt">Pressure-Induced</span> Phase Transition in CuGaO2</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiang, Cheng-Lu; Liu, Qi-Jun; Liu, Zheng-Tang</p> <p>2017-02-01</p> <p>We have studied the structural, elastic, electronic properties, and <span class="hlt">pressure-induced</span> phase transition of CuGaO2 by using the plane-<span class="hlt">wave</span> ultrasoft pseudopotential technique based on the first-principles density-functional theory (DFT). The obtained ground state properties of three phases were in agreement with previous works. The calculated enthalpy variations with <span class="hlt">pressure</span> showed that the structural phase transition ( β → 3R/2H) appeared at 65.5 ± 1 GPa. The changes in volume and band gap of β phase showed that there was a break between 30 and 40 GPa. The independent elastic constants of three phases were calculated. The 3R, 2H, and β phases were all mechanical stability and behaved in ductile manner under zero <span class="hlt">pressure</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22264111','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22264111"><span>Comparison of actinide production in traveling <span class="hlt">wave</span> and <span class="hlt">pressurized</span> water reactors</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Osborne, A.G.; Smith, T.A.; Deinert, M.R.</p> <p>2013-07-01</p> <p>The geopolitical problems associated with civilian nuclear energy production arise in part from the accumulation of transuranics in spent nuclear fuel. A traveling <span class="hlt">wave</span> reactor is a type of breed-burn reactor that could, if feasible, reduce the overall production of transuranics. In one possible configuration, a cylinder of natural or depleted uranium would be subjected to a fast neutron flux at one end. The neutrons would transmute the uranium, producing plutonium and higher actinides. Under the right conditions, the reactor could become critical, at which point a self-stabilizing fission <span class="hlt">wave</span> would form and propagate down the length of the reactor cylinder. The neutrons from the fission <span class="hlt">wave</span> would burn the fissile nuclides and transmute uranium ahead of the <span class="hlt">wave</span> to produce additional fuel. Fission <span class="hlt">waves</span> in uranium are driven largely by the production and fission of {sup 239}Pu. Simulations have shown that the fuel burnup can reach values greater than 400 MWd/kgIHM, before fission products poison the reaction. In this work we compare the production of plutonium and minor actinides produced in a fission <span class="hlt">wave</span> to that of a UOX fueled light water reactor, both on an energy normalized basis. The nuclide concentrations in the spent traveling <span class="hlt">wave</span> reactor fuel are computed using a one-group diffusion model and are verified using Monte Carlo simulations. In the case of the <span class="hlt">pressurized</span> water reactor, a multi-group collision probability model is used to generate the nuclide quantities. We find that the traveling <span class="hlt">wave</span> reactor produces about 0.187 g/MWd/kgIHM of transuranics compared to 0.413 g/MWd/kgIHM for a <span class="hlt">pressurized</span> water reactor running fuel enriched to 4.95 % and burned to 50 MWd/kgIHM. (authors)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001AGUSM..SM32D04A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001AGUSM..SM32D04A"><span>Determining Electron Density, <span class="hlt">Pressure</span>, and Temperature in Jupiter's Plasma Sheet Using the Galileo Plasma <span class="hlt">Wave</span> Instrument</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ansher, J. A.; Gurnett, D. A.; Khurana, K. K.; Kivelson, M. G.</p> <p>2001-05-01</p> <p>The plasma <span class="hlt">wave</span> instrument on board the Galileo spacecraft can be used to determine electron density in Jupiter's magnetosphere. Ordinary mode radio <span class="hlt">waves</span> are often detected in the form of non-thermal continuum radiation trapped in the magnetosphere at frequencies above the electron plasma frequency. By identifying the low-frequency cutoff of continuum radiation as the plasma frequency, an upper limit to the local electron density can be calculated. This technique has been used with the Galileo plasma <span class="hlt">wave</span> data to provide an electron density data set with approximately 37-second time resolution. Continuum radiation is detected by the plasma <span class="hlt">wave</span> instrument in much of Galileo's primary mission and electron density can be calculated at all System-III longitudes and radial distances beyond about 20-25 RJ. The density data set created using this technique is used here in conjunction with data from the Galileo magnetometer instrument and with Khurana's 1998 mathematical model of Jupiter's plasma sheet to study <span class="hlt">pressure</span> balance in the plasma sheet. As Jupiter rotates, the spacecraft encounters the plasma sheet and crosses the entire sheet from north to south, or south to north, in under five hours. Assuming there are no time dependent variations in the plasma sheet on this time scale, and negligible curvature to the magnetic field lines in this region, the sum of magnetic <span class="hlt">pressure</span> and particle <span class="hlt">pressure</span> across the plasma sheet should stay constant. Using electron density and magnetic field data, and varying the temperature parameter, best fits for the total constant <span class="hlt">pressure</span> and the corresponding temperature can be determined. These values can be determined throughout Jupiter's magnetosphere yielding <span class="hlt">pressure</span> and temperature profiles of Jupiter's plasma sheet between about 20 and 140 RJ. Typical temperatures determined using this technique are about 108 K, corresponding to energies of about 10 keV. The total <span class="hlt">pressure</span> decreases with radial distance from Jupiter as a power</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20090025975','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20090025975"><span>Development of Laser-<span class="hlt">induced</span> Grating Spectroscopy for Underwater Temperature Measurement in Shock <span class="hlt">Wave</span> Focusing Regions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gojani, Ardian B.; Danehy, Paul M.; Alderfer, David W.; Saito, Tsutomu; Takayama, Kazuyoshi</p> <p>2003-01-01</p> <p>In Extracorporeal Shock <span class="hlt">Wave</span> Lithotripsy (ESWL) underwater shock <span class="hlt">wave</span> focusing generates high <span class="hlt">pressures</span> at very short duration of time inside human body. However, it is not yet clear how high temperatures are enhanced at the spot where a shock <span class="hlt">wave</span> is focused. The estimation of such dynamic temperature enhancements is critical for the evaluation of tissue damages upon shock loading. For this purpose in the Interdisciplinary Shock <span class="hlt">Wave</span> Research Center a technique is developed which employs laser <span class="hlt">induced</span> thermal acoustics or Laser <span class="hlt">Induced</span> Grating Spectroscopy. Unlike most of gasdynamic methods of measuring physical quantities this provides a non-invasive one having spatial and temporal resolutions of the order of magnitude of 1.0 mm3 and 400 ns, respectively. Preliminary experiments in still water demonstrated that this method detected sound speed and hence temperature in water ranging 283 K to 333 K with errors of 0.5%. These results may be used to empirically establish the equation of states of water, gelatin or agar cells which will work as alternatives of human tissues.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004SPIE.5251..313G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004SPIE.5251..313G"><span>Development of laser-<span class="hlt">induced</span> grating spectroscopy for underwater temperature measurement in shock <span class="hlt">wave</span> focusing regions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gojani, Ardian B.; Danehy, Paul M.; Alderfer, David W.; Saito, Tsutomu; Takayama, Kazuyoshi</p> <p>2004-02-01</p> <p>In Extracorporeal Shock <span class="hlt">Wave</span> Lithotripsy (ESWL) underwater shock <span class="hlt">wave</span> focusing generates high <span class="hlt">pressures</span> at very short duration of time inside human body. However, it is not yet clear how high temperatures are enhanced at the spot where a shock <span class="hlt">wave</span> is focused. The estimation of such dynamic temperature enhancements is critical for the evaluation of tissue damages upon shock loading. For this purpose in the Interdisciplinary Shock <span class="hlt">Wave</span> Research Center a technique is developed which employs laser <span class="hlt">induced</span> thermal acoustics or Laser <span class="hlt">Induced</span> Grating Spectroscopy. Unlike most of gas-dynamic methods of measuring physical quantities this provides a non-invasive one having spatial and temporal resolutions of the order of magnitude of 1.0 mm 3 and 400 ns, respectively. Preliminary experiments in still water demonstrated that this method detected sound speed and hence temperature in water ranging 283 K to 333 K with errors of 0.5%. These results are used to empirically establish the equation of states of water, gelatin or agar cell which will work as alternatives of human tissues.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1038193','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1038193"><span><span class="hlt">Pressure</span> fluctuations beneath turbulent spots and instability <span class="hlt">wave</span> packets in a hypersonic boundary layer.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Beresh, Steven Jay; Casper, Katya M.; Schneider, Steven P.</p> <p>2010-12-01</p> <p>The development of turbulent spots in a hypersonic boundary layer was studied on the nozzle wall of the Boeing/AFOSR Mach-6 Quiet Tunnel. Under quiet flow conditions, the nozzle wall boundary layer remains laminar and grows very thick over the long nozzle length. This allows the development of large turbulent spots that can be readily measured with <span class="hlt">pressure</span> transducers. Measurements of naturally occurring <span class="hlt">wave</span> packets and developing turbulent spots were made. The peak frequencies of these natural <span class="hlt">wave</span> packets were in agreement with second-mode computations. For a controlled study, the breakdown of disturbances created by spark and glow perturbations were studied at similar freestream conditions. The spark perturbations were the most effective at creating large <span class="hlt">wave</span> packets that broke down into turbulent spots. The flow disturbances created by the controlled perturbations were analyzed to obtain amplitude criteria for nonlinearity and breakdown as well as the convection velocities of the turbulent spots. Disturbances first grew into linear instability <span class="hlt">waves</span> and then quickly became nonlinear. Throughout the nonlinear growth of the <span class="hlt">wave</span> packets, large harmonics are visible in the power spectra. As breakdown begins, the peak amplitudes of the instability <span class="hlt">waves</span> and harmonics decrease into the rising broad-band frequencies. Instability <span class="hlt">waves</span> are still visible on either side of the growing turbulent spots during this breakdown process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22353716','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22353716"><span>Stress-<span class="hlt">induced</span> chemical <span class="hlt">waves</span> in sediment burial diagenesis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Yifeng; Budd, David A</p> <p>2012-02-21</p> <p>Lateral metre-scale periodic variations in porosity and composition are found in many dolomite strata. Such variations may embed important information about dolomite formation and transformation. Here we show that these variations could be fossilized chemical <span class="hlt">waves</span> emerging from stress-mediated mineral-water interaction during sediment burial diagenesis. Under the overlying loading, crystals in higher porosity domains are subjected to a higher effective stress, causing <span class="hlt">pressure</span> solution. The dissolved species diffuse to and precipitate in neighbouring lower porosity domains, further reducing the porosity. This positive feedback leads to lateral porosity and compositional patterning in dolomite. The pattern geometry depends on fluid flow regimes. In a diffusion-dominated case, the low- and high-porosity domains alternate spatially with no directional preference, while, in the presence of an advective flow, this alternation occurs only along the flow direction, propagating like a chemical <span class="hlt">wave</span>. Our work provides a new perspective for interpreting diagenetic signatures in sedimentary rocks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25156172','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25156172"><span>Dominance of the forward compression <span class="hlt">wave</span> in determining pulsatile components of blood <span class="hlt">pressure</span>: similarities between inotropic stimulation and essential hypertension.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fok, Henry; Guilcher, Antoine; Brett, Sally; Jiang, Benyu; Li, Ye; Epstein, Sally; Alastruey, Jordi; Clapp, Brian; Chowienczyk, Phil</p> <p>2014-11-01</p> <p>Pulsatile components of blood <span class="hlt">pressure</span> may arise from forward (ventricular generated) or backward <span class="hlt">wave</span> travel in the arterial tree. The objective of this study was to determine the relative contributions of forward and backward <span class="hlt">waves</span> to pulsatility. We used <span class="hlt">wave</span> intensity and <span class="hlt">wave</span> separation analysis to determine pulsatile components of blood <span class="hlt">pressure</span> during inotropic and vasopressor stimulation by dobutamine and norepinephrine in normotensive subjects and compared pulse <span class="hlt">pressure</span> components in hypertensive (mean±SD, 48.8±11.3 years; 165±26.6/99±14.2 mm Hg) and normotensive subjects (52.2±12.6 years; 120±14.2/71±8.2 mm Hg). Dobutamine (7.5 μg/kg per minute) increased the forward compression <span class="hlt">wave</span> generated by the ventricle and increased pulse <span class="hlt">pressure</span> from 36.8±3.7 to 59.0±3.4 mm Hg (mean±SE) but had no significant effect on mean arterial <span class="hlt">pressure</span> or the midsystolic backward compression <span class="hlt">wave</span>. By contrast, norepinephrine (50 ng/kg per minute) had no significant effect on the forward compression <span class="hlt">wave</span> but increased the midsystolic backward compression <span class="hlt">wave</span>. Despite this increase in the backward compression <span class="hlt">wave</span>, and an increase in mean arterial <span class="hlt">pressure</span>, norepinephrine increased central pulse <span class="hlt">pressure</span> less than dobutamine (increases of 22.1±3.8 and 7.2±2.8 mm Hg for dobutamine and norepinephrine, respectively; P<0.02). An elevated forward <span class="hlt">wave</span> component (mean±SE, 50.4±3.4 versus 35.2±1.8 mm Hg, in hypertensive and normotensive subjects, respectively; P<0.001) accounted for approximately two thirds of the total difference in central pulse <span class="hlt">pressures</span> between hypertensive and normotensive subjects. Increased central pulse <span class="hlt">pressure</span> during inotropic stimulation and in essential hypertension results primarily from the forward compression <span class="hlt">wave</span>. © 2014 American Heart Association, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/570174','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/570174"><span>Use of Z-pinch sources for high-<span class="hlt">pressure</span> shock <span class="hlt">wave</span> studies</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Konrad, C.H.; Asay, J.R.; Hall, C.A.</p> <p>1998-01-01</p> <p>In this paper, we will discuss the use of z-pinch sources for shock <span class="hlt">wave</span> studies at multi-Mbar <span class="hlt">pressures</span>. Experimental plans to use the technique for absolute shock Hugoniot measurements are discussed. Recent developments have demonstrated the use of pulsed power techniques for producing intense radiation sources (Z pinches) for driving planar shock <span class="hlt">waves</span> in samples with spatial dimensions significantly larger than possible with other radiation sources. Initial indications are that using Z pinch sources for producing Planckian radiation sources in secondary hohlraums can be used to drive shock <span class="hlt">waves</span> in samples with diameters to a few millimeters and thickness approaching one millimeter in thickness. These dimensions provides the opportunity to measure both shock velocity and the particle velocity behind the shock front with accuracy comparable to that obtained with gun launchers. In addition, the peak hohlraum temperatures of nearly 150 eV that are now possible with Z pinch sources result in shock <span class="hlt">wave</span> <span class="hlt">pressures</span> approaching 45 Mbar in high impedance materials such as tungsten and 10-15 Mbar in low impedance materials such as aluminum and plastics. In this paper, we discuss the use of Z pinch sources for making accurate absolute EOS measurements in the megabar <span class="hlt">pressure</span> range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/115055','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/115055"><span>Thermal-hydraulic behaviors of vapor-liquid interface due to arrival of a <span class="hlt">pressure</span> <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Inoue, Akira; Fujii, Yoshifumi; Matsuzaki, Mitsuo</p> <p>1995-09-01</p> <p>In the vapor explosion, a <span class="hlt">pressure</span> <span class="hlt">wave</span> (shock <span class="hlt">wave</span>) plays a fundamental role for triggering, propagation and enhancement of the explosion. Energy of the explosion is related to the magnitude of heat transfer rate from hot liquid to cold volatile one. This is related to an increasing rate of interface area and to an amount of transient heat flux between the liquids. In this study, the characteristics of transient heat transfer and behaviors of vapor film both on the platinum tube and on the hot melt tin drop, under same boundary conditions have been investigated. It is considered that there exists a fundamental mechanism of the explosion in the initial expansion process of the hot liquid drop immediately after arrival of <span class="hlt">pressure</span> <span class="hlt">wave</span>. The growth rate of the vapor film is much faster on the hot liquid than that on the solid surface. Two kinds of roughness were observed, one due to the Taylor instability, by rapid growth of the explosion bubble, and another, nucleation sites were observed at the vapor-liquid interface. Based on detailed observation of early stage interface behaviors after arrival of a <span class="hlt">pressure</span> <span class="hlt">wave</span>, the thermal fragmentation mechanism is proposed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998ShWav...8..173J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998ShWav...8..173J"><span>Shock <span class="hlt">wave</span> <span class="hlt">induced</span> phase transition in α -FePO 4</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Joshi, K. D.; Suresh, N.; Jyoti, G.; Kulshreshtha, S. K.; Gupta, S. C.; Sikka, S. K.</p> <p></p> <p>Shock <span class="hlt">wave</span> <span class="hlt">induced</span> response of the berlinite form of FePO 4 has been investigated up to 8.5 GPa. The X-ray diffraction measurements on the shock recovered samples reveal transition to the mixture of an amorphous phase and an orthorhombic phase around 5 GPa. The proportion of the amorphous material in the recovered sample is found to decrease at higher <span class="hlt">pressure</span>. The results are interpreted in terms of a three-level free energy diagram for the crystal to amorphous transitions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994JPhy1...4.1539B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994JPhy1...4.1539B"><span>Superconductivity and magnetic field <span class="hlt">induced</span> spin density <span class="hlt">waves</span> in the (TMTTF)2X family</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Balicas, L.; Behnia, K.; Kang, W.; Canadell, E.; Auban-Senzier, P.; Jérome, D.; Ribault, M.; Fabre, J. M.</p> <p>1994-10-01</p> <p>We report magnetotransport measurements in the quasi one dimensional (Q-1-D) organic conductor (TMTTF)2Br at <span class="hlt">pressures</span> up to 26 kbar, clown to 0.45 K in magnetic fields up to 19 T along the c^{ast} direction. It is found that a superconducting ground state is stabilized under 26 kbar at T_C = 0.8 K. No magnetic field <span class="hlt">induced</span> spin density <span class="hlt">wave</span> (FISDW) transitions are observed below 19T unlike other Q-1-D superconductors pertaining to the selenium series. The computed amplitude of the interchain coupling along transverse directions is unable to explain the missing; FISDW instability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910004339','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910004339"><span>Turbulence modeling for sharp-fin-<span class="hlt">induced</span> shock <span class="hlt">wave</span>/turbulent boundary-layer interactions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Horstman, C. C.</p> <p>1990-01-01</p> <p>Solutions of the Reynolds averaged Navier-Stokes equations are presented and compared with a family of experimental results for the 3-D interaction of a sharp fin <span class="hlt">induced</span> shock <span class="hlt">wave</span> with a turbulent boundary layer. Several algebraic and two equation eddy viscosity turbulence models are employed. The computed results are compared with experimental surface <span class="hlt">pressure</span>, skin friction, and yaw angle data as well as the overall size of the interaction. Although the major feature of the flow fields are correctly predicted, several discrepancies are noted. Namely, the maximum skin friction values are significantly underpredicted for the strongest interaction cases. These and other deficiencies are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11308777','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11308777"><span>Kinetic model of ionization <span class="hlt">waves</span> in a positive column at intermediate <span class="hlt">pressures</span> in inert gases.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Golubovskii, Y B; Maiorov, V A; Nekutchaev, V O; Behnke, J; Behnke, J F</p> <p>2001-03-01</p> <p>A kinetic model of ionization <span class="hlt">waves</span> in the inert gas discharge is constructed, which is based on the simultaneous solution of the kinetic equation for electrons and the continuity equations for ions and excited atoms. The model corresponds to a range of intermediate <span class="hlt">pressures</span> and small currents, when elastic collisions dominate in the electron energy balance and electron-electron collisions are negligibly small. A linear theory of ionization <span class="hlt">waves</span> is constructed, growth rates and frequencies of <span class="hlt">wave</span> disturbances able to propagate in plasma are found. It is shown that there is an upper bound to the existence of striations by <span class="hlt">pressure</span>, as well as the lower bound by current. The self-consistent solution of the source system of equations is obtained, which describes a nonlinear <span class="hlt">wave</span>. The profile of electric field and the electron distribution function in this field are calculated. The results of calculations are compared with the experimental data. The wavelengths obtained are essentially larger than the electron energy relaxation length. Such <span class="hlt">waves</span> cannot be described within the limits of fluid models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000AIPC..505...97C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000AIPC..505...97C"><span>Shock <span class="hlt">induced</span> melting in aluminum: <span class="hlt">Wave</span> profile measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chhabildas, Lalit C.; Furnish, Michael D.; Reinhart, William D.</p> <p>2000-04-01</p> <p>We have developed launch capabilities that can propel macroscopic plates to hypervelocities (8 to 16 km/s). This capability has been used to determine the first time-resolved <span class="hlt">wave</span>-profile measurements unsing velocity interferometry techniques at impact velocities of 10 km/s. These measurements show that aluminum continues to exhibit normal release behavior to 161 GPa with complete loss of strength in the shocked state. Results of these experiments are discussed and compared with the results of lower-<span class="hlt">pressure</span> experiments conducted at lower impact velocities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6525439','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6525439"><span>Ventricular size and isotope cisternography in patients with acute transient rises of intracranial <span class="hlt">pressure</span> (plateau <span class="hlt">waves</span>)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hayashi, M.; Kobayashi, H.; Fujii, H.; Yamamoto, S.</p> <p>1982-12-01</p> <p>The size of the ventricular system and cerebrospinal fluid (CSF) flow were determined in 17 patients with plateau <span class="hlt">waves</span>, using computerized tomography (CT) and isotope cisternography. Some patients had increased intracranial <span class="hlt">pressure</span> (ICP) resulting from space-occupying lesions and other causes, and some had normal ICP observed in normal-<span class="hlt">pressure</span> hydrocephalus. The size and shape of the ventricular system during plateau <span class="hlt">wave</span> phases as ascertained by CT showed little or no change as compared with its size and shape during the interval phases between two <span class="hlt">waves</span>. It was also noticed that, in patients with supratentorial masses, the midline shift showed no difference in degree between the two phases. These findings suggest that there is little change in the intracranial CSF volume between the two phases, that is, there is little compensatory outflow of the intracranial CSF for the ICP variations. These results may also support the assumption that the plateau <span class="hlt">waves</span> are not caused by an intermittent obstruction of the CSF pathways. Isotope cisternography showed a marked delay of clearance of radioactivity from the intracranial CSF in 15 patients. The cisternographic pattern in patients with increased ICP and the absence of ventricular dilatation demonstrated an abnormally large accumulation of radioactivity over the cerebral convexities, and the pattern in patients with normal-<span class="hlt">pressure</span> hydrocephalus showed complete obstruction of the subarachnoid space over both cerebral convexities. These observations suggest that, in patients with plateau <span class="hlt">waves</span>, there is a marked delay in CSF absorption. The authors postulate that the reduction of CSF absorption may create a critically tight condition within the cranial cavity and act as a contributory factor in the development of the plateau <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3900925','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3900925"><span>Characterization of a Setup to test the Impact of High-Amplitude <span class="hlt">Pressure</span> <span class="hlt">Waves</span> on Living Cells</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Schmidt, Mischa; Kahlert, Ulf; Wessolleck, Johanna; Maciaczyk, Donata; Merkt, Benjamin; Maciaczyk, Jaroslaw; Osterholz, Jens; Nikkhah, Guido; Steinhauser, Martin O.</p> <p>2014-01-01</p> <p>The impact of <span class="hlt">pressure</span> <span class="hlt">waves</span> on cells may provide several possible applications in biology and medicine including the direct killing of tumors, drug delivery or gene transfection. In this study we characterize the physical properties of mechanical <span class="hlt">pressure</span> <span class="hlt">waves</span> generated by a nanosecond laser pulse in a setup with well-defined cell culture conditions. To systematically characterize the system on the relevant length and time scales (micrometers and nanoseconds) we use photon Doppler velocimetry (PDV) and obtain velocity profiles of the cell culture vessel at the passage of the <span class="hlt">pressure</span> <span class="hlt">wave</span>. These profiles serve as input for numerical <span class="hlt">pressure</span> <span class="hlt">wave</span> simulations that help to further quantify the <span class="hlt">pressure</span> conditions on the cellular length scale. On the biological level we demonstrate killing of glioblastoma cells and quantify experimentally the <span class="hlt">pressure</span> threshold for cell destruction. PMID:24458018</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014NatSR...4E3849S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014NatSR...4E3849S"><span>Characterization of a Setup to test the Impact of High-Amplitude <span class="hlt">Pressure</span> <span class="hlt">Waves</span> on Living Cells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmidt, Mischa; Kahlert, Ulf; Wessolleck, Johanna; Maciaczyk, Donata; Merkt, Benjamin; Maciaczyk, Jaroslaw; Osterholz, Jens; Nikkhah, Guido; Steinhauser, Martin O.</p> <p>2014-01-01</p> <p>The impact of <span class="hlt">pressure</span> <span class="hlt">waves</span> on cells may provide several possible applications in biology and medicine including the direct killing of tumors, drug delivery or gene transfection. In this study we characterize the physical properties of mechanical <span class="hlt">pressure</span> <span class="hlt">waves</span> generated by a nanosecond laser pulse in a setup with well-defined cell culture conditions. To systematically characterize the system on the relevant length and time scales (micrometers and nanoseconds) we use photon Doppler velocimetry (PDV) and obtain velocity profiles of the cell culture vessel at the passage of the <span class="hlt">pressure</span> <span class="hlt">wave</span>. These profiles serve as input for numerical <span class="hlt">pressure</span> <span class="hlt">wave</span> simulations that help to further quantify the <span class="hlt">pressure</span> conditions on the cellular length scale. On the biological level we demonstrate killing of glioblastoma cells and quantify experimentally the <span class="hlt">pressure</span> threshold for cell destruction.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/208315','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/208315"><span>Influence of pore <span class="hlt">pressure</span> and production-<span class="hlt">induced</span> changes in pore <span class="hlt">pressure</span> on in situ stress</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Teufel, L.W.</p> <p>1996-02-01</p> <p>Knowledge of in situ stress and how stress changes with reservoir depletion and pore <span class="hlt">pressure</span> drawdown is important in a multi-disciplinary approach to reservoir characterization, reservoir management, and improved oil recovery projects. This report summarizes a compilation of in situ stress data from six fields showing the effects of pore <span class="hlt">pressure</span> and production-<span class="hlt">induced</span> changes in pore <span class="hlt">pressure</span> on the minimum horizontal stress. The in situ stress data and corresponding pore <span class="hlt">pressure</span> data were obtained from field records of the operating companies and published reports. Horizontal stress was determined from closure <span class="hlt">pressure</span> data of hydraulic fractures and leak-off tests. The stress measurements clearly demonstrate that the total minimum-horizontal stress is dependent on pore <span class="hlt">pressure</span>. A decrease in pore <span class="hlt">pressure</span> either by geologic processes or production of a reservoir will result in a decrease in the total minimum-horizontal stress. The magnitude of changes in stress state with net changes in pore <span class="hlt">pressure</span> is dependent on local field conditions and cannot be accurately predicted by the uniaxial strain model that is commonly used by the petroleum industry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ASPC..474..185W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ASPC..474..185W"><span>Evidence of the Correspondence of EIT <span class="hlt">Waves</span> and Coronal Mass Ejections <span class="hlt">Induced</span> <span class="hlt">Waves</span> Using a Three-Dimensional Magnetohydrodynamic Simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, S. T.; Wu, C.-C.; Liou, K.</p> <p>2013-04-01</p> <p>Before the discovery of EIT <span class="hlt">waves</span> and coronal mass ejections (CMEs) it was already known that Moreton <span class="hlt">waves</span> were observed to propagate across the solar disk during some solar flares. This magnetohydrodynamic <span class="hlt">wave</span> was explained as the intersecting line between the edge of an expanding global coronal wavefront and the chromosphere (Uchida, 1968) where Uchida concluded that the Moreton <span class="hlt">wave</span> was a fast mode MHD <span class="hlt">wave</span>. In this presentation, we will show that the EIT <span class="hlt">wave</span> could be a part of a CME <span class="hlt">induced</span> <span class="hlt">wave</span> propagating across the solar disk. To illustrate this scenario, we have employed a global 3D MHD model (Wu et al. 2001) to simulate this phenomenon for the May 12, 1997 event which was an Earth-directed CME observed by SOHO/EIT (Thompson et al. 1998). To carry out this simulation, the measured global magnetic fields obtained from the Stanford University Wilcox Solar Observatory (WSO) were used as the inputs to the simulation model. We were able to show that the scenario suggested by Uchida (1968), namely, the observed EIT <span class="hlt">wave</span> propagating across the solar disk could be caused by the intersection line between the edge of an expanding CME <span class="hlt">induced</span> <span class="hlt">wave</span> front and the chromosphere. In addition to the flare source scenario, we concluded that an EIT (or EUV) <span class="hlt">wave</span> can also be a part of a flare <span class="hlt">induced</span> coronal <span class="hlt">wave</span> with its foot print on the Sun's surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.P41A1877A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.P41A1877A"><span>Impact-<span class="hlt">induced</span> shock <span class="hlt">pressure</span> distribution in a heterogeneous planetary interior</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arkani-Hamed, J.</p> <p>2012-12-01</p> <p>The shock <span class="hlt">pressure</span> distribution inside planetary interiors has been investigated on the basis of scaling laws [1,2] and using numerical hydrocode models [2,3]. Here I present a new shock ray formulations derived on the basis of the Hugoniot equations to calculate the impact-<span class="hlt">induced</span> shock <span class="hlt">pressure</span> distribution inside heterogeneous terrestrial planets with radially varying physical parameters both in the solid mantle and in the underlying liquid core. Considering a single vertical impact, the formulations are derived in an axi-symmetric spherical coordinate system where the impact is assumed to occur at the north pole. In previous studies the scaling laws of shock <span class="hlt">pressure</span> distribution [5] have been used to determine the impact heating of the planetary interiors by direct shock <span class="hlt">waves</span> [2]. Because the main concern was the impact heating of the core, the heating of the antipodal region of the mantle was not investigated. The present study not only considers the impact heating of the entire planetary mantle by direct shock <span class="hlt">waves</span> but also investigates the effects of the reflected shock <span class="hlt">waves</span> inside the core. The direct shockwave propagating southward in the core intersects the core mantle boundary in the antipodal region where it partly transmits to the mantle and partly reflects back into the core. Both transmitted and reflected <span class="hlt">waves</span> converge toward the axis of symmetry and create strong shock <span class="hlt">pressure</span> near the axis in the antipodal region. Consequently, the antipodal region is significantly heated. In particular, the antipodal region of the core is heated twice, first by the direct shock <span class="hlt">wave</span> as it propagates southward, and second by the reflected <span class="hlt">waves</span> which actually increases in intensity close to the axis of symmetry. This feature has been demonstrated by the hydrocode models [3,4] but not by the scaling models based on direct shock <span class="hlt">wave</span> propagation [1]. The new algorithm is applied to the impact heating of Mars, and the results are compared with those determined</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3895877','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3895877"><span>Irreversibility of <span class="hlt">Pressure</span> <span class="hlt">Induced</span> Boron Speciation Change in Glass</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Smedskjaer, Morten M.; Youngman, Randall E.; Striepe, Simon; Potuzak, Marcel; Bauer, Ute; Deubener, Joachim; Behrens, Harald; Mauro, John C.; Yue, Yuanzheng</p> <p>2014-01-01</p> <p>It is known that the coordination number (CN) of atoms or ions in many materials increases through application of sufficiently high <span class="hlt">pressure</span>. This also applies to glassy materials. In boron-containing glasses, trigonal BO3 units can be transformed into tetrahedral BO4 under <span class="hlt">pressure</span>. However, one of the key questions is whether the <span class="hlt">pressure</span>-quenched CN change in glass is reversible upon annealing below the ambient glass transition temperature (Tg). Here we address this issue by performing 11B NMR measurements on a soda lime borate glass that has been <span class="hlt">pressure</span>-quenched at ~0.6 GPa near Tg. The results show a remarkable phenomenon, i.e., upon annealing at 0.9Tg the <span class="hlt">pressure-induced</span> change in CN remains unchanged, while the pressurised values of macroscopic properties such as density, refractive index, and hardness are relaxing. This suggests that the <span class="hlt">pressure-induced</span> changes in macroscopic properties of soda lime borate glasses compressed up to ~0.6 GPa are not attributed to changes in the short-range order in the glass, but rather to changes in overall atomic packing density and medium-range structures. PMID:24442182</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24442182','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24442182"><span>Irreversibility of <span class="hlt">pressure</span> <span class="hlt">induced</span> boron speciation change in glass.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Smedskjaer, Morten M; Youngman, Randall E; Striepe, Simon; Potuzak, Marcel; Bauer, Ute; Deubener, Joachim; Behrens, Harald; Mauro, John C; Yue, Yuanzheng</p> <p>2014-01-20</p> <p>It is known that the coordination number (CN) of atoms or ions in many materials increases through application of sufficiently high <span class="hlt">pressure</span>. This also applies to glassy materials. In boron-containing glasses, trigonal BO3 units can be transformed into tetrahedral BO4 under <span class="hlt">pressure</span>. However, one of the key questions is whether the <span class="hlt">pressure</span>-quenched CN change in glass is reversible upon annealing below the ambient glass transition temperature (Tg). Here we address this issue by performing (11)B NMR measurements on a soda lime borate glass that has been <span class="hlt">pressure</span>-quenched at ~0.6 GPa near Tg. The results show a remarkable phenomenon, i.e., upon annealing at 0.9Tg the <span class="hlt">pressure-induced</span> change in CN remains unchanged, while the pressurised values of macroscopic properties such as density, refractive index, and hardness are relaxing. This suggests that the <span class="hlt">pressure-induced</span> changes in macroscopic properties of soda lime borate glasses compressed up to ~0.6 GPa are not attributed to changes in the short-range order in the glass, but rather to changes in overall atomic packing density and medium-range structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JThSc..20..181C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JThSc..20..181C"><span>A new modeling approach of <span class="hlt">pressure</span> <span class="hlt">waves</span> at the inlet of internal combustion engines</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chalet, David; Mahé, Alexandre; Hétet, Jean-François; Migaud, Jérôme</p> <p>2011-06-01</p> <p>This paper presents a new model used to describe the propagation of <span class="hlt">pressure</span> <span class="hlt">waves</span> at the inlet systems of internal combustion engine. In the first part, an analogy is made between the compressible air in a pipe and a mechanical ideal mass damper spring system. A new model is then presented and the parameters of this model are determined by the use of an experimental setup (shock tube test bench). With this model, a transfer function is defined in order to link directly the <span class="hlt">pressure</span> and the air mass flow rate. In the second part, the model is included into an internal combustion engine simulation code. The results obtained with this code are compared to experimental ones which are measured on a one-cylinder engine test bench. This last one is driven by an electric motor in order to study only the effect of the <span class="hlt">pressure</span> <span class="hlt">waves</span> on the engine behavior. A good agreement is obtained between the experimental results and the numerical ones and the new approach is an alternative method for modeling the <span class="hlt">pressure</span> <span class="hlt">wave</span> phenomena in an internal combustion engine manifold.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18924198','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18924198"><span>Effect of osmolytes on <span class="hlt">pressure-induced</span> unfolding of proteins: a high-<span class="hlt">pressure</span> SAXS study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Krywka, Christina; Sternemann, Christian; Paulus, Michael; Tolan, Metin; Royer, Catherine; Winter, Roland</p> <p>2008-12-22</p> <p>Herein, we explore the effect of different types of osmolytes on the high-<span class="hlt">pressure</span> stability and tertiary structure of a well-characterized monomeric protein, staphylococcal nuclease (SNase). Changes in the denaturation <span class="hlt">pressure</span> and the radius of gyration are obtained in the presence of different concentrations of trimethylamine N-oxide (TMAO), glycerol and urea. To reveal structural changes in the protein upon compression at various osmolyte conditions, small-angle X-ray scattering (SAXS) experiments were carried out. To this end, a new high-<span class="hlt">pressure</span> cell suitable for high-precision SAXS studies at synchrotron sources was built, which allows one to carry out scattering experiments up to maximum <span class="hlt">pressures</span> of about 7 kbar. Our data clearly indicate that the osmolytes that stabilize proteins against temperature-<span class="hlt">induced</span> unfolding drastically increase their <span class="hlt">pressure</span> stability and that the elliptically shaped curve of the <span class="hlt">pressure</span>-temperature-stability diagram of proteins is shifted to higher temperatures and <span class="hlt">pressures</span> with increasing osmolyte concentration. A drastic stabilization is observed for the osmolyte TMAO, which exhibits not only a significant stabilization against temperature-<span class="hlt">induced</span> unfolding, but also a particularly strong stabilization of the protein against <span class="hlt">pressure</span>. In fact, such findings are in accordance with in vivo studies (for example P. J. Yancey, J. Exp. Biol. 2005, 208, 2819-2830), where unusually high TMAO concentrations in some deep-sea animals were found. Conversely, chaotropic agents such as urea have a strong destabilizing effect on both the temperature and <span class="hlt">pressure</span> stability of the protein. Our data also indicate that sufficiently high TMAO concentrations might be able to largely offset the destabilizing effect of urea. The different scenarios observed are discussed in the context of recent experimental and theoretical studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.774a2054S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.774a2054S"><span>Superconductivity of Cu/CuOx interface formed by shock-<span class="hlt">wave</span> <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shakhray, D. V.; Avdonin, V. V.; Palnichenko, A. V.</p> <p>2016-11-01</p> <p>A mixture of powdered Cu and CuO has been subjected to shock-<span class="hlt">wave</span> <span class="hlt">pressure</span> of 350 kbar with following quenching of the vacuum-encapsulated product to 77 K. The ac magnetic susceptibility measurements of the samples have revealed metastable superconductivity with Tc ≈ 19 K, characterized by glassy dynamics of the shielding currents below Tc . Comparison of the ac susceptibility and the DC magnetization measurements infers that the superconductivity arises within the granular interfacial layer formed between metallic Cu and its oxides due to the shock-<span class="hlt">wave</span> treatment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyC..498...54P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyC..498...54P"><span>Superconductivity of Cu/CuOx interface formed by shock-<span class="hlt">wave</span> <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Palnichenko, A. V.; Sidorov, N. S.; Shakhrai, D. V.; Avdonin, V. V.; Vyaselev, O. M.; Khasanov, S. S.</p> <p>2014-03-01</p> <p>A mixture of powdered Cu and CuO has been subjected to a shock-<span class="hlt">wave</span> <span class="hlt">pressure</span> of ≃350 kbar with following quenching of the vacuum-encapsulated product to ≈77 K. The ac magnetic susceptibility measurements of the samples have revealed metastable superconductivity with Tc≈19.5 K, characterized by glassy dynamics of the shielding currents below Tc. Comparison of the ac susceptibility and the dc magnetization measurements infers that the superconductivity arises within the granular interfacial layer formed between metallic Cu and its oxides due to the shock-<span class="hlt">wave</span> treatment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15003268','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15003268"><span><span class="hlt">Pressure</span> <span class="hlt">wave</span> measurements from thermal cook-off of an HMX based high explosive</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Forbes, J W; Tarver, C M; Urtiew, P A; Garcia, F; Greenwood, D W; Vandersall, K S</p> <p>2000-10-10</p> <p>A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting <span class="hlt">pressure</span> <span class="hlt">wave</span> and how this <span class="hlt">wave</span> propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15004116','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15004116"><span><span class="hlt">Pressure</span> <span class="hlt">Wave</span> Measurements from Thermal Cook-off of an HMX Based Explosive</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Forbes, J W; Tarver, C M; Urtiew, P A; Garcia, F; Greenwood, D W; Vandersall, K S</p> <p>2001-05-09</p> <p>A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting <span class="hlt">pressure</span> <span class="hlt">wave</span> and how this <span class="hlt">wave</span> propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15005663','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15005663"><span><span class="hlt">Pressure</span> <span class="hlt">Wave</span> Measurements from Thermal Cook-Off of an HMX Based High Explosive PBX 9501</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Garcia, F; Forbes, J W; Tarver, C M; Urtiew, P A; Greenwood, D W; Vandersall, K S</p> <p>2001-05-31</p> <p>A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting <span class="hlt">pressure</span> <span class="hlt">wave</span> and how this <span class="hlt">wave</span> propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5290427','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5290427"><span>Estimated Pulse <span class="hlt">Wave</span> Velocity Calculated from Age and Mean Arterial Blood <span class="hlt">Pressure</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Greve, Sara V.; Laurent, Stephan; Olsen, Michael H.</p> <p>2017-01-01</p> <p>In a recently published paper, Greve et al [J Hypertens 2016;34:1279-1289] investigate whether the estimated carotid-femoral pulse <span class="hlt">wave</span> velocity (ePWV), calculated using an equation derived from the relationship between carotid-femoral pulse <span class="hlt">wave</span> velocity (cfPWV), age, and blood <span class="hlt">pressure</span>, predicts cardiovascular disease (CVD) as good as the measured cfPWV. Because ePWV predicts CVD as good as cfPWV, some might wonder whether ePWV could be replaced by cfPWV, which is a time-consuming measurement requiring an expensive apparatus. This question is addressed in this mini-review. PMID:28229052</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/9784125','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/9784125"><span><span class="hlt">Pressure-induced</span> landau-type transition in stishovite</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Andrault; Fiquet; Guyot; Hanfland</p> <p>1998-10-23</p> <p>A Rietveld structural analysis of stishovite, with angle-dispersive x-ray diffraction synchrotron source at the European Synchrotron Radiation Facility, confirmed a CaCl2 form of stishovite distortion at 54 +/- 1 gigapascals but confirmed no further phase transformation up to 120 gigapascals. The deviatoric stress that is usually encountered at such <span class="hlt">pressures</span> was relaxed after yttrium-aluminum-garnet-laser heating. A single Birch-Murnaghan equation of state fits volumes of stishovite and a CaCl2 form, showing that the tetragonal distortion occurs without a substantial change in volume. At the 54-gigapascal transition, the <span class="hlt">pressure-induced</span> lattice modifications were similar to those found in a Landau-type temperature-<span class="hlt">induced</span> transition. It is proposed that, above the transition <span class="hlt">pressure</span>, the critical temperature increases above 300 kelvin, so that the lower entropy form becomes stable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/8231298','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/8231298"><span><span class="hlt">Wave</span> propagation with different <span class="hlt">pressure</span> signals: an experimental study on the latex tube.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ursino, M; Artioli, E; Gallerani, M</p> <p>1993-07-01</p> <p>To have deeper insight into the main factors affecting <span class="hlt">wave</span> propagation in real hydraulic lines, we measured the true propagation coefficient in two latex rubber tubes via the three-point <span class="hlt">pressure</span> method. The measurements were performed using both sinusoidal <span class="hlt">pressure</span> signals of different amplitudes and periodic square <span class="hlt">waves</span> as well as aperiodic <span class="hlt">pressure</span> impulses. The results obtained were then compared with those predicted by a classic linear model valuable for a purely elastic maximally tethered tube. Our measurements demonstrate that the three-point <span class="hlt">pressure</span> method may introduce significant errors at low frequencies (below 1 Hz in the present experiments) when the distance between two consecutive transducers becomes much lower than the wavelength. The pattern of phase velocity in the range 2-20 Hz turns out to be about 10 per cent higher than the theoretical one computed using the static value of the Young modulus. This result supports the idea that the dynamic Young modulus of the material is slightly higher than that measured in static conditions. The experimental attenuation per wavelength is significantly higher than the theoretical one over most of the frequencies examined, and settles at a constant value as frequency increases. Introduction of wall viscoelasticity in the theoretical model can explain only a portion of the observed high frequency damping and <span class="hlt">wave</span> attenuation. Finally, increasing the amplitude of <span class="hlt">pressure</span> changes significantly affects the measured value of the propagation coefficient, especially at those frequencies for which direct and reflected <span class="hlt">waves</span> sum together in a positive fashion. In these conditions we observed a moderate increase in phase velocity and a much more evident increase in attenuation per wavelength.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001AGUFM.S12F..04B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001AGUFM.S12F..04B"><span>A New Mechanism for Pore <span class="hlt">Pressure</span> Changes <span class="hlt">Induced</span> by Distant Earthquakes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brodsky, E. E.; Roeloffs, E.; Woodcock, D.; Gall, I.; Manga, M.</p> <p>2001-12-01</p> <p>Observations during the Mw=7.3 1992 Landers earthquake, Mw=7.4 Izmit earthquake and Mw=7.2 Hector Mine earthquake suggest that seismicity is triggered hundreds of kilometers from a mainshock epicenter. This puzzling phenomenon is not explained by traditional elastic models of seismic stresses. The fact that the triggered sites are often geothermal or magmatic suggests that fluids may be an important part of the triggering process. Rapid changes in pore <span class="hlt">pressure</span> either reduce the effective stress on faults locally or prompt hydrofracturing to initiate local earthquakes. The challenge is to discover how the seismic <span class="hlt">waves</span> generate a change in pore fluid <span class="hlt">pressure</span>. We constrain a mechanism for seismically-<span class="hlt">induced</span> pore <span class="hlt">pressure</span> changes by studying coseismic water level drops at a well in Grants Pass, Oregon. Water level drops at the site have been associated with earthquakes for nearly 20 years. High-sample rate (up to 1 Hz) digital water level data is available for the two coseismic drops that have occurred since 1994. The approach of this study is to use the amplification of the seismic <span class="hlt">waves</span> in the well to constrain variations of the aquifer properties during the water level drops. We find that the amplification of the seismic <span class="hlt">waves</span> in the well is consistent with standard theory for 7 digitally recorded events without drops, but during an earthquake with a drop a dramatic change in amplification occurs during the passage of the Rayleigh <span class="hlt">waves</span>. The change in amplification indicates that the transmissivity increases by a factor of 50 during the 11 cm coseismic water level drop accompanying the 1999 Mw=7.5 1999 Oaxaca, Mexico earthquake. Based on these observations, we propose a new model for coseismic pore <span class="hlt">pressure</span> changes. Drops occur if an earthquake occurs when the well has become temporarily clogged by a solid precipitate or sediment. The seismic shaking <span class="hlt">induces</span> a flow which removes the obstruction. Once a barrier is removed, water flows rapidly to generate dramatic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950058892&hterms=cold+plasma&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcold%2Bplasma','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950058892&hterms=cold+plasma&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcold%2Bplasma"><span>Radial energy transport by magnetospheric ULF <span class="hlt">waves</span>: Effects of magnetic curvature and plasma <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kouznetsov, Igor; Lotko, William</p> <p>1995-01-01</p> <p>The 'radial' transport of energy by internal ULF <span class="hlt">waves</span>, stimulated by dayside magnetospheric boundary oscillations, is analyzed in the framework of one-fluid magnetohydrodynamics. (the term radial is used here to denote the direction orthogonal to geomagnetic flux surfaces.) The model for the inhomogeneous magnetospheric plasma and background magnetic field is axisymmetric and includes radial and parallel variations in the magnetic field, magnetic curvature, plasma density, and low but finite plasma <span class="hlt">pressure</span>. The radial mode structure of the coupled fast and intermediate MHD <span class="hlt">waves</span> is determined by numerical solution of the inhomogeneous <span class="hlt">wave</span> equation; the parallel mode structure is characterized by a Wentzel-Kramer-Brillouin (WKB) approximation. Ionospheric dissipation is modeled by allowing the parallel <span class="hlt">wave</span> number to be complex. For boudnary oscillations with frequencies in the range from 10 to 48 mHz, and using a dipole model for the background magnetic field, the combined effects of magnetic curvature and finite plasma <span class="hlt">pressure</span> are shown to (1) enhance the amplitude of field line resonances by as much as a factor of 2 relative to values obtained in a cold plasma or box-model approximation for the dayside magnetosphere; (2) increase the energy flux delivered to a given resonance by a factor of 2-4; and (3) broaden the spectral width of the resonance by a factor of 2-3. The effects are attributed to the existence of an 'Alfven buoyancy oscillation,' which approaches the usual shear mode Alfven <span class="hlt">wave</span> at resonance, but unlike the shear Alfven mode, it is dispersive at short perpendicular wavelengths. The form of dispersion is analogous to that of an internal atmospheric gravity <span class="hlt">wave</span>, with the magnetic tension of the curved background field providing the restoring force and allowing radial propagation of the mode. For nominal dayside parameters, the propagation band of the Alfven buoyancy <span class="hlt">wave</span> occurs between the location of its (field line) resonance and that of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950058892&hterms=wave+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dwave%2Benergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950058892&hterms=wave+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dwave%2Benergy"><span>Radial energy transport by magnetospheric ULF <span class="hlt">waves</span>: Effects of magnetic curvature and plasma <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kouznetsov, Igor; Lotko, William</p> <p>1995-01-01</p> <p>The 'radial' transport of energy by internal ULF <span class="hlt">waves</span>, stimulated by dayside magnetospheric boundary oscillations, is analyzed in the framework of one-fluid magnetohydrodynamics. (the term radial is used here to denote the direction orthogonal to geomagnetic flux surfaces.) The model for the inhomogeneous magnetospheric plasma and background magnetic field is axisymmetric and includes radial and parallel variations in the magnetic field, magnetic curvature, plasma density, and low but finite plasma <span class="hlt">pressure</span>. The radial mode structure of the coupled fast and intermediate MHD <span class="hlt">waves</span> is determined by numerical solution of the inhomogeneous <span class="hlt">wave</span> equation; the parallel mode structure is characterized by a Wentzel-Kramer-Brillouin (WKB) approximation. Ionospheric dissipation is modeled by allowing the parallel <span class="hlt">wave</span> number to be complex. For boudnary oscillations with frequencies in the range from 10 to 48 mHz, and using a dipole model for the background magnetic field, the combined effects of magnetic curvature and finite plasma <span class="hlt">pressure</span> are shown to (1) enhance the amplitude of field line resonances by as much as a factor of 2 relative to values obtained in a cold plasma or box-model approximation for the dayside magnetosphere; (2) increase the energy flux delivered to a given resonance by a factor of 2-4; and (3) broaden the spectral width of the resonance by a factor of 2-3. The effects are attributed to the existence of an 'Alfven buoyancy oscillation,' which approaches the usual shear mode Alfven <span class="hlt">wave</span> at resonance, but unlike the shear Alfven mode, it is dispersive at short perpendicular wavelengths. The form of dispersion is analogous to that of an internal atmospheric gravity <span class="hlt">wave</span>, with the magnetic tension of the curved background field providing the restoring force and allowing radial propagation of the mode. For nominal dayside parameters, the propagation band of the Alfven buoyancy <span class="hlt">wave</span> occurs between the location of its (field line) resonance and that of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1810509H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1810509H"><span>Tracking Ocean Gravity <span class="hlt">Waves</span> in Real-time: Highlights of Bottom <span class="hlt">Pressure</span> Data Recorded on Ocean Networks Canada's NEPTUNE observatory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Heesemann, Martin; Mihaly, Steve; Gemmrich, Johannes; Davis, Earl; Thomson, Richard; Dewey, Richard</p> <p>2016-04-01</p> <p>Ocean Networks Canada operates two cabled ocean observatories off Vancouver Island on Canada's west coast. The regional NEPTUNE observatory spans the entire Juan de Fuca tectonic plate from the coast across the subduction zone to the hydrothermally active Endeavour Segment of the Juan de Fuca Ridge Segment while the VENUS observatory focuses on coastal processes. Both observatories collect data on physical, chemical, biological, and geological aspects of the ocean over long time periods, supporting research on complex earth processes. High-precision bottom <span class="hlt">pressure</span> recorders (BPR) deployed on the NEPTUNE observatory are capable of detecting a wide range of phenomena related to sea level variations. The observatory BPRs provide observations of nano-resolution (with respect to full scale of the instrument) <span class="hlt">pressure</span> variations which correspond to sub-millimeter scale surface water displacements in several kilometers of water. Detected signals include tides, tsunamis, infragravity <span class="hlt">waves</span>, swell, <span class="hlt">wave-induced</span> microseisms, storm surge, and seismic signals. Spectral analysis reveals many of these phenomena with periods ranging from a few seconds to many hours. Dispersion patterns from distant swells are prominent in the swell and microseism bands. By comparing the difference of arrival times between longer period <span class="hlt">waves</span>, which arrive first, and shorter period <span class="hlt">waves</span> we can estimate the distance the swells travelled since they were generated. Using this information, swell can be tracked back to specific storms across the Pacific. The presentation will high-light some examples of the mentioned phenomena in the continuous time-series that in some instances are more than seven years long.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010HPR....30..547K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010HPR....30..547K"><span>The quality of high <span class="hlt">pressure-induced</span> and heat-<span class="hlt">induced</span> yuzu marmalade</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kuwada, Hiroko; Jibu, Yuri; Teramoto, Ai; Fuchigami, Michiko</p> <p>2010-12-01</p> <p>Yuzu is a typical Japanese citrus with a desirable smell. The objectives of this study are to establish a process for <span class="hlt">pressure-induced</span> marmalade (without both heating or the addition of pectin) and compare it with heat-<span class="hlt">induced</span> marmalade. Sliced peel (flavedo) was soaked in 2% citric acid solution (pH 2.0). Albedo, endocarp and juice sacs were homogenized with 0.3% citric acid solution (pH 2.5). After soaking for 24 h, these were mixed and 50% or 60% sucrose of the total weight was added, then <span class="hlt">pressurized</span> at 500 MPa or boiled (process A). Process B: all processing was done at pH 2.7. Peel of high <span class="hlt">pressure-induced</span> marmalade maintained a natural color. Flavedo in heat-<span class="hlt">induced</span> marmalade was softer than that of <span class="hlt">pressure-induced</span> marmalade. There was no difference in viscosity between heat-<span class="hlt">induced</span> and high <span class="hlt">pressure-induced</span> marmalade. High <span class="hlt">pressure-induced</span> marmalade with 50% sugar was preferred by a sensory test because fresh flavor and color were maintained.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70025827','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70025827"><span>Shock-<span class="hlt">wave-induced</span> fracturing of calcareous nannofossils from the Chesapeake Bay impact crater</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>,</p> <p>2003-01-01</p> <p>Fractured calcareous nannofossils of the genus Discoaster from synimpact sediments within the Chesapeake Bay impact crater demonstrate that other petrographic shock indicators exist for the cratering process in addition to quartz minerals. Evidence for shock-<span class="hlt">induced</span> taphonomy includes marginal fracturing of rosette-shaped Discoaster species into pentagonal shapes and <span class="hlt">pressure</span>- and temperature-<span class="hlt">induced</span> dissolution of ray tips and edges of discoasters. Rotational deformation of individual crystallites may be the mechanism that produces the fracture pattern. Shock-<span class="hlt">wave</span>-fractured calcareous nannofossils were recovered from synimpact matrix material representing tsunami or resurge sedimentation that followed impact. Samples taken from cohesive clasts within the crater rubble show no evidence of shock-<span class="hlt">induced</span> fracturing. The data presented here support growing evidence that microfossils can be used to determine the intensity and timing of wet-impact cratering.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/40277263','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/40277263"><span>Giant Deformations of a Liquid-Liquid Interface <span class="hlt">Induced</span> by the Optical Radiation <span class="hlt">Pressure</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Casner, Alexis; Delville, Jean-Pierre</p> <p>2001-07-30</p> <p>Because of the small momentum of photons, very intense fields are generally required to bend a liquid interface with the optical radiation <span class="hlt">pressure</span>. We explore this issue in a near-critical phase-separated liquid mixture to vary continuously the meniscus softness by tuning the temperature. Low power continuous laser <span class="hlt">waves</span> become sufficient to <span class="hlt">induce</span> huge stationary bulges. Using the beam size to build an ''optical'' Bond number, Bo , we investigate the crossover from low to large Bo . The whole set of data collapses onto a single master curve which illustrates the universality of the phenomenon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JPSCP...1a2063Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JPSCP...1a2063Y"><span><span class="hlt">Pressure-Induced</span> Phase Transitions of n-Tridecane</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamashita, Motoi</p> <p></p> <p><span class="hlt">Pressure-induced</span> phase transition behavior of n-tridecane from the ordered phase through the rotator phase into the liquid phase has been investigated by using Fourier transform infrared spectroscopy at 25 °C. The transition between the ordered and rotator phases has been observed in the <span class="hlt">pressure</span> range of 270-220 MPa and the transition between the rotator and liquid phases has been observed in the <span class="hlt">pressure</span> range of 171-112 MPa, within the experimental error of ±50 MPa. The populations of the -gtg- + -gtg'-, -gg- and gt- defects determined from the methylene wagging mode are smaller in the rotator phase than in the liquid phase and are smaller under higher <span class="hlt">pressure</span> in both of the rotator and liquid phases. A relationship has been found between the conformation and the intensity of the 890 cm-1 band, which has been assigned as the methyl rocking mode and has been considered as insensitive to conformation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvD..93l3502O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvD..93l3502O"><span>Chiral primordial gravitational <span class="hlt">waves</span> from dilaton <span class="hlt">induced</span> delayed chromonatural inflation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Obata, Ippei; Soda, Jiro; CLEO Collaboration</p> <p>2016-06-01</p> <p>We study inflation driven by a dilaton and an axion, both of which are coupled to a SU(2) gauge field. We find that the inflation driven by the dilaton occurs in the early stage of inflation during which the gauge field grows due to the gauge-kinetic function. When the energy density of magnetic fields catches up with that of electric fields, chromonatural inflation takes over in the late stage of inflation, which we call delayed chromonatural inflation. Thus, the delayed chromonatural inflation driven by the axion and the gauge field is <span class="hlt">induced</span> by the dilaton. The interesting outcome of the model is the generation of chiral primordial gravitational <span class="hlt">waves</span> on small scales. Since the gauge field is inert in the early stage of inflation, it is viable in contrast to the conventional chromonatural inflation. We find the parameter region where chiral gravitational <span class="hlt">waves</span> are generated in a frequency range higher than nHz, which are potentially detectable in future gravitational <span class="hlt">wave</span> interferometers and pulsar-timing arrays such as DECi-hertz Interferometer Gravitational <span class="hlt">wave</span> Observatory (DECIGO), evolved Laser Interferometer Space Antenna (eLISA), and Square Kilometer Array (SKA).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1806h0010S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1806h0010S"><span>The stress-<span class="hlt">induced</span> surface <span class="hlt">wave</span> velocity variations in concrete</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Spalvier, Agustin; Bittner, James; Evani, Sai Kalyan; Popovics, John S.</p> <p>2017-02-01</p> <p>This investigation studies the behavior of surface <span class="hlt">wave</span> velocity in concrete specimens subjected to low levels of compressive and tensile stress in beams from applied flexural loads. Beam specimen is loaded in a 4-point-load bending configuration, generating uniaxial compression and tension stress fields at the top and bottom surfaces of the beam, respectively. Surface <span class="hlt">waves</span> are generated through contactless air-coupled transducers and received through contact accelerometers. Results show a clear distinction in responses from compression and tension zones, where velocity increases in the former and decreases in the latter, with increasing load levels. These trends agree with existing acoustoelastic literature. Surface <span class="hlt">wave</span> velocity tends to decrease more under tension than it tends to increase under compression, for equal load levels. It is observed that even at low stress levels, surface <span class="hlt">wave</span> velocity is affected by acoustoelastic effects, coupled with plastic effects (stress-<span class="hlt">induced</span> damage). The acoustoelastic effect is isolated by means of considering the Kaiser effect and by experimentally mitigating the viscoelastic effects of concrete. Results of this ongoing investigation contribute to the overall knowledge of the acoustoelastic behavior of concrete. Applications of this knowledge may include structural health monitoring of members under flexural loads, improved high order modelling of materials, and validation of results seen in dynamic acoustoelasticity testing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNS41B1923R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNS41B1923R"><span>Analysis of <span class="hlt">Wave</span> Fields <span class="hlt">induced</span> by Offshore Pile Driving</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruhnau, M.; Heitmann, K.; Lippert, T.; Lippert, S.; von Estorff, O.</p> <p>2015-12-01</p> <p>Impact pile driving is the common technique to install foundations for offshore wind turbines. With each hammer strike the steel pile - often exceeding 6 m in diameter and 80 m in length - radiates energy into the surrounding water and soil, until reaching its targeted penetration depth. Several European authorities introduced limitations regarding hydroacoustic emissions during the construction process to protect marine wildlife. Satisfying these regulations made the development and application of sound mitigation systems (e.g. bubble curtains or insulation screens) inevitable, which are commonly installed within the water column surrounding the pile or even the complete construction site. Last years' advances have led to a point, where the seismic energy tunneling the sound mitigation systems through the soil and radiating back towards the water column gains importance, as it confines the maximum achievable sound mitigation. From an engineering point of view, the challenge of deciding on an effective noise mitigation layout arises, which especially requires a good understanding of the soil-dependent <span class="hlt">wave</span> field. From a geophysical point of view, the pile acts like a very unique line source, generating a characteristic <span class="hlt">wave</span> field dominated by inclined <span class="hlt">wave</span> fronts, diving as well as head <span class="hlt">waves</span>. Monitoring the seismic arrivals while the pile penetration steadily increases enables to perform quasi-vertical seismic profiling. This work is based on datasets that have been collected within the frame of three comprehensive offshore measurement campaigns during pile driving and demonstrates the potential of seismic arrivals <span class="hlt">induced</span> by pile driving for further soil characterization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvB..95b4510L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvB..95b4510L"><span><span class="hlt">Pressure-induced</span> superconductivity in Bi single crystals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Yufeng; Wang, Enyu; Zhu, Xiyu; Wen, Hai-Hu</p> <p>2017-01-01</p> <p>Measurements on resistivity and magnetic susceptibility have been carried out for Bi single crystals under <span class="hlt">pressures</span> up to 10.5 GPa. The temperature dependent resistivity shows a semimetallic behavior at ambient and low <span class="hlt">pressures</span> (below about 1.6 GPa). This is followed by an upturn of resistivity in the low temperature region when the <span class="hlt">pressure</span> is increased, which is explained as a semiconductor behavior. This feature gradually gets enhanced up to a <span class="hlt">pressure</span> of about 2.52 GPa. Then a nonmonotonic temperature dependent resistivity appears upon further increasing <span class="hlt">pressure</span>, which is accompanied by a strong suppression to the low temperature resistivity upturn. Simultaneously, a superconducting transition occurs at about 3.92 K under a <span class="hlt">pressure</span> of about 2.63 GPa. With further increasing <span class="hlt">pressure</span>, a second superconducting transition emerges at about 7 K under about 2.8 GPa. For these two superconducting states, the superconductivity <span class="hlt">induced</span> magnetic screening volumes are quite large. As the <span class="hlt">pressure</span> further increases to 8.1 GPa, we observe the third superconducting transition at about 8.2 K. The resistivity measurements under magnetic field allow us to determine the upper critical fields μ0Hc 2 of the superconducting phases. The upper critical field for the phase with Tc=3.92 K is extremely low. Based on the Werthamer-Helfand-Hohenberg (WHH) theory, the estimated value of μ0Hc 2 for this phase is about 0.103 T, while the upper critical field for the phase with Tc=7 K is very high with a value of about 4.56 T. Finally, we present a <span class="hlt">pressure</span> dependent phase diagram of Bi single crystals. Our results reveal the interesting and rich physics in bismuth single crystals under high <span class="hlt">pressure</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1295510','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1295510"><span>Negative <span class="hlt">pressures</span> and spallation in water drops subjected to nanosecond shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Stan, Claudiu A.; Willmott, Philip R.; Stone, Howard A.; Koglin, Jason E.; Liang, Mengning; Aquila, Andrew L.; Robinson, Joseph S.; Gumerlock, Karl L.; Blaj, Gabriel; Sierra, Raymond G.; Boutet, Sebastien; Guillet, Serge A. H.; Curtis, Robin H.; Vetter, Sharon L.; Loos, Henrik; Turner, James L.; Decker, Franz -Josef</p> <p>2016-05-16</p> <p>Most experimental studies of cavitation in liquid water at negative <span class="hlt">pressures</span> reported cavitation at tensions significantly smaller than those expected for homogeneous nucleation, suggesting that achievable tensions are limited by heterogeneous cavitation. We generated tension pulses with nanosecond rise times in water by reflecting cylindrical shock <span class="hlt">waves</span>, produced by X-ray laser pulses, at the internal surface of drops of water. Depending on the X-ray pulse energy, a range of cavitation phenomena occurred, including the rupture and detachment, or spallation, of thin liquid layers at the surface of the drop. When spallation occurred, we evaluated that negative <span class="hlt">pressures</span> below –100 MPa were reached in the drops. As a result, we model the negative <span class="hlt">pressures</span> from shock reflection experiments using a nucleation-and-growth model that explains how rapid decompression could outrun heterogeneous cavitation in water, and enable the study of stretched water close to homogeneous cavitation <span class="hlt">pressures</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960009429&hterms=Bls&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DBls','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960009429&hterms=Bls&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DBls"><span>Reduction of fluctuating <span class="hlt">pressure</span> loads in shock <span class="hlt">wave</span> turbulent boundary layer interactions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barter, John W.; Dolling, David S.</p> <p>1995-01-01</p> <p>Fluctuating surface <span class="hlt">pressure</span> measurements have been made to investigate the effectiveness of boundary layer separators (BLS's) in reducing the fluctuating <span class="hlt">pressure</span> loads produced by separated shock <span class="hlt">wave</span> turbulent boundary layer interactions. Measurements have been made under unswept and swept compression corner interactions in a Mach 5 flow. BLS's fix the separation location and eliminate the large-amplitude, low-frequency fluctuating <span class="hlt">pressure</span> loads upstream of the compression corners. The loads on the unswept compression corner face are reduced by as much as 59%. The BLS's also shift the mean <span class="hlt">pressure</span> distribution on the unswept corner face in the streamwise direction. Results show that the loads on the corner face vary with the BLS height and the distance between the BLS and the compression corner. Suggestions for the optimum placement and the use of the BLS's are also made.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1295510-negative-pressures-spallation-water-drops-subjected-nanosecond-shock-waves','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1295510-negative-pressures-spallation-water-drops-subjected-nanosecond-shock-waves"><span>Negative <span class="hlt">pressures</span> and spallation in water drops subjected to nanosecond shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Stan, Claudiu A.; Willmott, Philip R.; Stone, Howard A.; ...</p> <p>2016-05-16</p> <p>Most experimental studies of cavitation in liquid water at negative <span class="hlt">pressures</span> reported cavitation at tensions significantly smaller than those expected for homogeneous nucleation, suggesting that achievable tensions are limited by heterogeneous cavitation. We generated tension pulses with nanosecond rise times in water by reflecting cylindrical shock <span class="hlt">waves</span>, produced by X-ray laser pulses, at the internal surface of drops of water. Depending on the X-ray pulse energy, a range of cavitation phenomena occurred, including the rupture and detachment, or spallation, of thin liquid layers at the surface of the drop. When spallation occurred, we evaluated that negative <span class="hlt">pressures</span> below –100 MPamore » were reached in the drops. As a result, we model the negative <span class="hlt">pressures</span> from shock reflection experiments using a nucleation-and-growth model that explains how rapid decompression could outrun heterogeneous cavitation in water, and enable the study of stretched water close to homogeneous cavitation <span class="hlt">pressures</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27182751','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27182751"><span>Negative <span class="hlt">Pressures</span> and Spallation in Water Drops Subjected to Nanosecond Shock <span class="hlt">Waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Stan, Claudiu A; Willmott, Philip R; Stone, Howard A; Koglin, Jason E; Liang, Mengning; Aquila, Andrew L; Robinson, Joseph S; Gumerlock, Karl L; Blaj, Gabriel; Sierra, Raymond G; Boutet, Sébastien; Guillet, Serge A H; Curtis, Robin H; Vetter, Sharon L; Loos, Henrik; Turner, James L; Decker, Franz-Josef</p> <p>2016-06-02</p> <p>Most experimental studies of cavitation in liquid water at negative <span class="hlt">pressures</span> reported cavitation at tensions significantly smaller than those expected for homogeneous nucleation, suggesting that achievable tensions are limited by heterogeneous cavitation. We generated tension pulses with nanosecond rise times in water by reflecting cylindrical shock <span class="hlt">waves</span>, produced by X-ray laser pulses, at the internal surface of drops of water. Depending on the X-ray pulse energy, a range of cavitation phenomena occurred, including the rupture and detachment, or spallation, of thin liquid layers at the surface of the drop. When spallation occurred, we evaluated that negative <span class="hlt">pressures</span> below -100 MPa were reached in the drops. We model the negative <span class="hlt">pressures</span> from shock reflection experiments using a nucleation-and-growth model that explains how rapid decompression could outrun heterogeneous cavitation in water, and enable the study of stretched water close to homogeneous cavitation <span class="hlt">pressures</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1295510','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1295510"><span>Negative <span class="hlt">pressures</span> and spallation in water drops subjected to nanosecond shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Stan, Claudiu A.; Willmott, Philip R.; Stone, Howard A.; Koglin, Jason E.; Liang, Mengning; Aquila, Andrew L.; Robinson, Joseph S.; Gumerlock, Karl L.; Blaj, Gabriel; Sierra, Raymond G.; Boutet, Sebastien; Guillet, Serge A. H.; Curtis, Robin H.; Vetter, Sharon L.; Loos, Henrik; Turner, James L.; Decker, Franz -Josef</p> <p>2016-05-16</p> <p>Most experimental studies of cavitation in liquid water at negative <span class="hlt">pressures</span> reported cavitation at tensions significantly smaller than those expected for homogeneous nucleation, suggesting that achievable tensions are limited by heterogeneous cavitation. We generated tension pulses with nanosecond rise times in water by reflecting cylindrical shock <span class="hlt">waves</span>, produced by X-ray laser pulses, at the internal surface of drops of water. Depending on the X-ray pulse energy, a range of cavitation phenomena occurred, including the rupture and detachment, or spallation, of thin liquid layers at the surface of the drop. When spallation occurred, we evaluated that negative <span class="hlt">pressures</span> below –100 MPa were reached in the drops. As a result, we model the negative <span class="hlt">pressures</span> from shock reflection experiments using a nucleation-and-growth model that explains how rapid decompression could outrun heterogeneous cavitation in water, and enable the study of stretched water close to homogeneous cavitation <span class="hlt">pressures</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.705a2029A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.705a2029A"><span>Arterial pulse <span class="hlt">pressure</span> amplification described by means of a nonlinear <span class="hlt">wave</span> model: characterization of human aging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alfonso, M.; Cymberknop, L.; Armentano, R.; Pessana, F.; Wray, S.; Legnani, W.</p> <p>2016-04-01</p> <p>The representation of blood <span class="hlt">pressure</span> pulse as a combination of solitons captures many of the phenomena observed during its propagation along the systemic circulation. The aim of this work is to analyze the applicability of a compartmental model for propagation regarding the <span class="hlt">pressure</span> pulse amplification associated with arterial aging. The model was applied to blood <span class="hlt">pressure</span> waveforms that were synthesized using solitons, and then validated by waveforms obtained from individuals from differentiated age groups. Morphological changes were verified in the blood <span class="hlt">pressure</span> waveform as a consequence of the aging process (i.e. due to the increase in arterial stiffness). These changes are the result of both a nonlinear interaction and the phenomena present in the propagation of nonlinear mechanic <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011GeoJI.186.1245C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011GeoJI.186.1245C"><span>Anisotropic poroelasticity and <span class="hlt">wave-induced</span> fluid flow: harmonic finite-element simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carcione, J. M.; Santos, J. E.; Picotti, S.</p> <p>2011-09-01</p> <p>A dominant P-<span class="hlt">wave</span> attenuation mechanism in reservoir rocks at seismic frequencies is due to <span class="hlt">wave-induced</span> fluid flow (mesoscopic loss). The P-<span class="hlt">wave</span> <span class="hlt">induces</span> a fluid-<span class="hlt">pressure</span> difference at mesoscopic-scale inhomogeneities (larger than the pore size but smaller than the wavelength), generating fluid flow and slow (diffusion) Biot <span class="hlt">waves</span>. The theory has been developed in the 1970s for the symmetry axis of the equivalent transversely isotropic (TI) medium corresponding to a finely layered medium, and has recently been generalized to all propagation angles. The new theory states that the fluid-flow direction is perpendicular to the layering plane and it is independent of the loading direction. As a consequence, the relaxation behaviour can be described by a single relaxation function, since the medium consists of plane homogeneous layers. Besides P-<span class="hlt">wave</span> losses, the coupling between the qP and qSV <span class="hlt">waves</span> generates shear-<span class="hlt">wave</span> anisotropic velocity dispersion and attenuation. In this work, we introduce a set of quasi-static numerical experiments to determine the equivalent viscoelastic TI medium to a finely layered poroelastic medium, which is validated using a recently developed analytical solution. The modelling technique is the finite-element (FE) method, where the equations of motion are solved in the space-frequency domain. Numerical rock physics may, in many circumstances, offer an alternative to laboratory measurements. Numerical experiments are inexpensive and informative since the physical process of <span class="hlt">wave</span> propagation can be inspected during the experiment. Moreover, they are repeatable, essentially free from experimental errors, and may easily be run using alternative models of the rock and fluid properties. We apply the methodology to the Utsira aquifer of the North Sea, where carbon dioxide (CO2) has been injected during the last 15 years. The tests consider alternating layers of the same rock saturated with gas and brine and a sequence of gas-saturated sandstone and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27225867','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27225867"><span>Lower Blood <span class="hlt">Pressure-Induced</span> Renal Hypoperfusion Promotes Cisplatin-<span class="hlt">Induced</span> Nephrotoxicity.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mizuno, Tomohiro; Hayashi, Takahiro; Shimabukuro, Yuka; Murase, Maho; Hayashi, Hiroki; Ishikawa, Kazuhiro; Takahashi, Kazuo; Yuzawa, Yukio; Yamada, Shigeki; Nagamatsu, Tadashi</p> <p>2016-01-01</p> <p>Cisplatin-<span class="hlt">induced</span> nephrotoxicity primarily occurs in the proximal tubules, and tubular injuries reduce glomerular filtration rates. Lower blood <span class="hlt">pressure</span> causes renal hypoperfusion, which promotes ischemic acute kidney injury (AKI). Our study examined the relationship between lower blood <span class="hlt">pressure-induced</span> renal hypoperfusion and cisplatin-<span class="hlt">induced</span> nephrotoxicity. The relationship between cisplatin use and hypoalbuminemia is not clear. This study consisted of Japanese patients who received cisplatin as the first-line chemotherapy at Fujita Health University Hospital from April 2006 to December 2012. Hypoalbuminemia was defined as serum albumin levels ≤3.5 mg/dl. Patients who experienced lower blood <span class="hlt">pressure</span> during chemotherapy were included in the lower blood <span class="hlt">pressure</span> group (n = 229), and those who did not were included in the normal blood <span class="hlt">pressure</span> group (n = 743). Total cisplatin dose in the normal blood <span class="hlt">pressure</span> and lower blood <span class="hlt">pressure</span> groups was 58.9 ± 23.8 and 55.0 ± 20.4 mg/m2, respectively. The rate of severe nephrotoxicity was higher and overall survival was shorter in the lower blood <span class="hlt">pressure</span> group than in the normal blood <span class="hlt">pressure</span> group. In a multivariable analysis, lower blood <span class="hlt">pressure</span> significantly correlated with hypoalbuminemia. To prevent ischemic AKI, nutrition and cachexia controlling are important parts of cancer treatment. © 2016 S. Karger AG, Basel.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23031416','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23031416"><span>A non-invasive technique for estimating carpal tunnel <span class="hlt">pressure</span> by measuring shear <span class="hlt">wave</span> speed in tendon: a feasibility study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Yuexiang; Qiang, Bo; Zhang, Xiaoming; Greenleaf, James F; An, Kai-Nan; Amadio, Peter C; Zhao, Chunfeng</p> <p>2012-11-15</p> <p>Although a close relationship between carpal tunnel <span class="hlt">pressure</span> and median nerve dysfunction has been found, the current methods for <span class="hlt">pressure</span> measurements are invasive, using a catheter in the carpal canal to monitor the <span class="hlt">pressure</span>. A noninvasive method for quantifying carpal tunnel <span class="hlt">pressure</span> would be useful as an alternative to the catheter method. In this study, a simplified experimental model was developed to measure the shear <span class="hlt">wave</span> speed in a canine Achilles tendon under different tunnel <span class="hlt">pressures</span>. The results showed that the speed of <span class="hlt">waves</span> through the inside-tunnel tendon had a linear relationship with the <span class="hlt">pressure</span> in the tunnel (first measurement: r=0.966, P<0.001; second measurement: r=0.970, P<0.001). This indicates that the tendon could serve as a strain gauge to evaluate the tunnel <span class="hlt">pressure</span> by detecting the changes of <span class="hlt">wave</span> propagation speed. However, further validations in human cadavers and clinical subjects are necessary. Copyright © 2012 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/969240','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/969240"><span><span class="hlt">Pressure</span> dependence of the optical properties of the charge-density-<span class="hlt">wave</span> compound LaTe2</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lavagnini, M.; Sacchetti, A.; Degiorgi, L.; Arcangeletti, E.; Baldassarre, L.; Postorino, P.; Lupi, S.; Perucchi, A.; Shin, K.Y.; Fisher, I.R.; /Stanford U., Geballe Lab.</p> <p>2009-12-14</p> <p>We report the <span class="hlt">pressure</span> dependence of the optical response of LaTe{sub 2}, which is deep in the charge-density-<span class="hlt">wave</span> (CDW) ground state even at 300 K. The reflectivity spectrum is collected in the mid-infrared spectral range at room temperature and at <span class="hlt">pressures</span> between 0 and 7 GPa. We extract the energy scale due to the single particle excitation across the CDW gap and the Drude weight. We establish that the gap decreases upon compressing the lattice, while the Drude weight increases. This signals a reduction in the quality of nesting upon applying <span class="hlt">pressure</span>, therefore <span class="hlt">inducing</span> a lesser impact of the CDW condensate on the electronic properties of LaTe{sub 2}. The consequent suppression of the CDW gap leads to a release of additional charge carriers, manifested by the shift of weight from the gap feature into the metallic component of the optical response. On the contrary, the power-law behavior, seen in the optical conductivity at energies above the gap excitation and indicating a weakly interacting limit within the Tomonaga-Luttinger liquid scenario, seems to be only moderately dependent on <span class="hlt">pressure</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JMiMi..23h5018K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JMiMi..23h5018K"><span>CMOS-compatible ruggedized high-temperature Lamb <span class="hlt">wave</span> <span class="hlt">pressure</span> sensor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kropelnicki, P.; Muckensturm, K.-M.; Mu, X. J.; Randles, A. B.; Cai, H.; Ang, W. C.; Tsai, J. M.; Vogt, H.</p> <p>2013-08-01</p> <p>This paper describes the development of a novel ruggedized high-temperature <span class="hlt">pressure</span> sensor operating in lateral field exited (LFE) Lamb <span class="hlt">wave</span> mode. The comb-like structure electrodes on top of aluminum nitride (AlN) were used to generate the <span class="hlt">wave</span>. A membrane was fabricated on SOI wafer with a 10 µm thick device layer. The sensor chip was mounted on a <span class="hlt">pressure</span> test package and <span class="hlt">pressure</span> was applied to the backside of the membrane, with a range of 20-100 psi. The temperature coefficient of frequency (TCF) was experimentally measured in the temperature range of -50 °C to 300 °C. By using the modified Butterworth-van Dyke model, coupling coefficients and quality factor were extracted. Temperature-dependent Young's modulus of composite structure was determined using resonance frequency and sensor interdigital transducer (IDT) wavelength which is mainly dominated by an AlN layer. Absolute sensor phase noise was measured at resonance to estimate the sensor <span class="hlt">pressure</span> and temperature sensitivity. This paper demonstrates an AlN-based <span class="hlt">pressure</span> sensor which can operate in harsh environment such as oil and gas exploration, automobile and aeronautic applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17781564','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17781564"><span>Elastic <span class="hlt">wave</span> velocities of lunar samples at high <span class="hlt">pressures</span> and their geophysical implications.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kanamori, H; Nur, A; Chung, D; Wones, D; Simmons, G</p> <p>1970-01-30</p> <p>Ultrasonic measurement of P and S velocities of Apollo 11 lunar samples 10020, 10057, and 10065 to 5 kilobars <span class="hlt">pressure</span> at room temperature shows a pronounced increase of velocity (as much as twofold) for the first 2 kilobars. The travel times predicted from the velocity-depth curve of sample 10057 are consistent with the results of the Apollo 12 seismic experiments. At <span class="hlt">pressures</span> below 200 bars, the samples are highly attenuating; for both P and S <span class="hlt">waves</span>, the value of Q is about 10.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E2111Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E2111Y"><span>Gravity-<span class="hlt">wave</span> <span class="hlt">induced</span> CO2 clouds on Mars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yiǧit, Erdal; Medvedev, Alexander S.; Hartogh, Paul</p> <p>2016-07-01</p> <p>We present the first general circulation model simulations that quantify and reproduce patches of extremely cold air required for CO2 condensation and cloud formation in the Martian mesosphere. They are created by subgrid-scale gravity <span class="hlt">waves</span> (GWs) accounted for in the model with the whole atmosphere GW parameterization of Yiǧit et al. (2008)}. Distributions of GW-<span class="hlt">induced</span> temperature fluctuations and occurrences of supersaturation conditions are in a good agreement with observations of high-altitude CO2 ice clouds. Our study confirms the key role of GWs in facilitating CO2 cloud formation, discusses their tidal modulation, and predicts clouds at altitudes higher than have been observed to date. Reference: Yiǧit, E., A. D. Aylward, and A. S. Medvedev (2008), Parameterization of the effects of vertically propagating gravity <span class="hlt">waves</span> for thermosphere general circulation models: Sensitivity study, J. Geophys. Res., 113, D19106, doi:10.1029/2008JD010135.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvB..91q4440U','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvB..91q4440U"><span>Spin-<span class="hlt">wave-induced</span> spin torque in Rashba ferromagnets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Umetsu, Nobuyuki; Miura, Daisuke; Sakuma, Akimasa</p> <p>2015-05-01</p> <p>We study the effects of Rashba spin-orbit coupling on the spin torque <span class="hlt">induced</span> by spin <span class="hlt">waves</span>, which are the plane-<span class="hlt">wave</span> dynamics of magnetization. The spin torque is derived from linear-response theory, and we calculate the dynamic spin torque by considering the impurity-ladder-sum vertex corrections. This dynamic spin torque is divided into three terms: a damping term, a distortion term, and a correction term for the equation of motion. The distorting torque describes a phenomenon unique to the Rashba spin-orbit coupling system, where the distorted motion of magnetization precession is subjected to the anisotropic force from the Rashba coupling. The oscillation mode of the precession exhibits an elliptical trajectory, and the ellipticity depends on the strength of the nesting effects, which could be reduced by decreasing the electron lifetime.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013M%26PS...48..115G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013M%26PS...48..115G"><span>Propagation of impact-<span class="hlt">induced</span> shock <span class="hlt">waves</span> in porous sandstone using mesoscale modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>GÜLdemeister, Nicole; WÜNnemann, Kai; Durr, Nathanael; Hiermaier, Stefan</p> <p>2013-01-01</p> <p><title type="main">Abstract-Generation and propagation of shock <span class="hlt">waves</span> by meteorite impact is significantly affected by material properties such as porosity, water content, and strength. The objective of this work was to quantify processes related to the shock-<span class="hlt">induced</span> compaction of pore space by numerical modeling, and compare the results with data obtained in the framework of the Multidisciplinary Experimental and Modeling Impact Research Network (MEMIN) impact experiments. We use mesoscale models resolving the collapse of individual pores to validate macroscopic (homogenized) approaches describing the bulk behavior of porous and water-saturated materials in large-scale models of crater formation, and to quantify localized shock amplification as a result of pore space crushing. We carried out a suite of numerical models of planar shock <span class="hlt">wave</span> propagation through a well-defined area (the "sample") of porous and/or water-saturated material. The porous sample is either represented by a homogeneous unit where porosity is treated as a state variable (macroscale model) and water content by an equation of state for mixed material (ANEOS) or by a defined number of individually resolved pores (mesoscale model). We varied porosity and water content and measured thermodynamic parameters such as shock <span class="hlt">wave</span> velocity and particle velocity on meso- and macroscales in separate simulations. The mesoscale models provide additional data on the heterogeneous distribution of peak shock <span class="hlt">pressures</span> as a consequence of the complex superposition of reflecting rarefaction <span class="hlt">waves</span> and shock <span class="hlt">waves</span> originating from the crushing of pores. We quantify the bulk effect of porosity, the reduction in shock <span class="hlt">pressure</span>, in terms of Hugoniot data as a function of porosity, water content, and strength of a quartzite matrix. We find a good agreement between meso-, macroscale models and Hugoniot data from shock experiments. We also propose a combination of a porosity compaction model (ɛ-α model) that was</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhD...50H5201Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhD...50H5201Y"><span>Numerical and experimental study on atmospheric <span class="hlt">pressure</span> ionization <span class="hlt">waves</span> propagating through a U-shape channel</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yan, Wen; Xia, Yang; Bi, Zhenhua; Song, Ying; Wang, Dezhen; Sosnin, Eduard A.; Skakun, Victor S.; Liu, Dongping</p> <p>2017-08-01</p> <p>A 2D computational study of ionization <span class="hlt">waves</span> propagating in U-shape channels at atmospheric <span class="hlt">pressure</span> was performed, with emphasis on the effect of voltage polarity and the curvature of the bend. The discharge was ignited by a HV needle electrode inside the channel, and power was applied in the form of a trapezoidal pulse lasting 2 µs. We have shown that behavior of ionization <span class="hlt">waves</span> propagating in U-shape channels was quite different with that in straight tubes. For positive polarity of applied voltage, the ionization <span class="hlt">waves</span> tended to propagate along one side of walls rather than filling the channel. The propagation velocity of ionization <span class="hlt">waves</span> predicted by the simulation was in good agreement with the experiment results; the velocity was first increasing rapidly in the vicinity of the needle tip and then decreasing with the increment of propagation distance. Then we have studied the influence of voltage polarity on discharge characteristics. For negative polarity, the ionization <span class="hlt">waves</span> tended to propagate along the opposite side of the wall, while the discharge was more diffusive and volume-filling compared with the positive case. It was found that the propagation velocity for the negative ionization <span class="hlt">wave</span> was higher than that for the positive one. Meanwhile, the propagation of the negative ionization <span class="hlt">wave</span> depended less on the pre-ionization level than the positive ionization <span class="hlt">wave</span>. Finally, the effect of the radius of curvature was studied. Simulations have shown that the propagation speeds were sensitive to the radii of the curvature of the channels for both polarities. Higher radii of curvature tended to have higher speed and longer length of plasma. The simulation results were supported by experimental observations under similar discharge conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/866800','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/866800"><span>Instantaneous and efficient surface <span class="hlt">wave</span> excitation of a low <span class="hlt">pressure</span> gas or gases</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Levy, Donald J.; Berman, Samuel M.</p> <p>1988-01-01</p> <p>A system for instantaneously ionizing and continuously delivering energy in the form of surface <span class="hlt">waves</span> to a low <span class="hlt">pressure</span> gas or mixture of low <span class="hlt">pressure</span> gases, comprising a source of rf energy, a discharge container, (such as a fluorescent lamp discharge tube), an rf shield, and a coupling device responsive to rf energy from the source to couple rf energy directly and efficiently to the gas or mixture of gases to ionize at least a portion of the gas or gases and to provide energy to the gas or gases in the form of surface <span class="hlt">waves</span>. The majority of the rf power is transferred to the gas or gases near the inner surface of the discharge container to efficiently transfer rf energy as excitation energy for at least one of the gases. The most important use of the invention is to provide more efficient fluorescent and/or ultraviolet lamps.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/921152','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/921152"><span>New experimental capabilities and theoretical insights of high <span class="hlt">pressure</span> compression <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Orlikowski, D; Nguyen, J; Patterson, J R; Minich, R; Martin, L P; Holmes, N</p> <p>2007-07-20</p> <p>Currently there are three platforms that offer quasi-isentropic compression or ramp-<span class="hlt">wave</span> compression (RWC): light-gas gun, magnetic flux (Z-pinch), and laser. We focus here on the light-gas gun technique and on some current theoretical insights from experimental data. A gradient impedance through the length of the impactor provides the <span class="hlt">pressure</span> pulse upon impactor to the subject material. Applications and results are given concerning high-<span class="hlt">pressure</span> strength and liquid to solid, phase transition of water plus its associated phase fraction history. We also introduce the Korteweg-deVries-Burgers equation as a means to understand the evolution these RWC <span class="hlt">waves</span> that propagate through the thickness of the subject material. This equation has the necessary competition between non-linear, dispersion, and dissipation processes, which is shown through observed structures that are manifested in the experimental particle velocity histories. Such methodology points towards a possible quantifiable dissipation, through which RWC experiments may be analyzed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21466521','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21466521"><span>Theoretical study of the light <span class="hlt">pressure</span> force acting on a spherical dielectric particle of an arbitrary size in the interference field of two plane monochromatic electromagnetic <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Guzatov, D V; Gaida, L S; Afanas'ev, Anatolii A</p> <p>2008-12-31</p> <p>The light <span class="hlt">pressure</span> force acting on a spherical dielectric particle in the interference field of two plane monochromatic electromagnetic <span class="hlt">waves</span> is studied in detail for different particle radii and angles of incidence of <span class="hlt">waves</span>. (light <span class="hlt">pressure</span>)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1983PhDT........10C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1983PhDT........10C"><span>Nonlinear acoustics in a dispersive continuum: Random <span class="hlt">waves</span>, radiation <span class="hlt">pressure</span>, and quantum noise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cabot, M. A.</p> <p></p> <p>The nonlinear interaction of sound with sound is studied using dispersive hydrodynamics which derived from a variational principle and the assumption that the internal energy density depends on gradients of the mass density. The attenuation of sound due to nonlinear interaction with a background is calculated and is shown to be sensitive to both the nature of the dispersion and decay bandwidths. The theoretical results are compared to those of low temperature helium experiments. A kinetic equation which described the nonlinear self-inter action of a background is derived. When a Deybe-type cutoff is imposed, a white noise distribution is shown to be a stationary distribution of the kinetic equation. The attenuation and spectrum of decay of a sound <span class="hlt">wave</span> due to nonlinear interaction with zero point motion is calculated. In one dimension, the dispersive hydrodynamic equations are used to calculate the Langevin and Rayleigh radiation <span class="hlt">pressures</span> of <span class="hlt">wave</span> packets and solitary <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22060520','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22060520"><span>Fractional-calculus model for temperature and <span class="hlt">pressure</span> <span class="hlt">waves</span> in fluid-saturated porous rocks.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Garra, Roberto</p> <p>2011-09-01</p> <p>We study a fractional time derivative generalization of a previous Natale-Salusti model about nonlinear temperature and <span class="hlt">pressure</span> <span class="hlt">waves</span>, propagating in fluid-saturated porous rocks. Their analytic solutions, i.e., solitary shock <span class="hlt">waves</span> characterized by a sharp front, are here generalized, introducing a formalism that allows memory mechanisms. In realistic <span class="hlt">wave</span> propagation in porous media we must take into account spatial or temporal variability of permeability, diffusivity, and other coefficients due to the system "history." Such a rock fracturing or fine particulate migration could affect the rock and its pores. We therefore take into account these phenomena by introducing a fractional time derivative to simulate a memory-conserving formalism. We also discuss this generalized model in relation to the theory of dynamic permeability and tortuosity in fluid-saturated porous media. In such a realistic model we obtain exact solutions of Burgers' equation with time fractional derivatives in the inviscid case.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26237557','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26237557"><span>Reflected rather than forward <span class="hlt">wave</span> <span class="hlt">pressures</span> account for brachial <span class="hlt">pressure</span>-independent relations between aortic <span class="hlt">pressure</span> and end-organ changes in an African community.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sibiya, Moekanyi J; Woodiwiss, Angela J; Booysen, Hendrik L; Raymond, Andrew; Millen, Aletta M E; Maseko, Muzi J; Majane, Olebogeng H I; Sareli, Pinhas; Libhaber, Elena; Norton, Gavin R</p> <p>2015-10-01</p> <p>To determine whether brachial blood <span class="hlt">pressure</span> (BP)-independent relations between aortic <span class="hlt">pressure</span> and cardiovascular damage are better explained by reflected (backward) (Pb) or forward (Pf) <span class="hlt">wave</span> <span class="hlt">pressure</span> effects. In 1174 participants from a community of African ancestry, we assessed central aortic pulse <span class="hlt">pressure</span> (PPc), Pb, and Pf (radial applanation tonometry, SphygmoCor) as well as left ventricular mass index (LVMI) (n = 786), aortic pulse <span class="hlt">wave</span> velocity (PWV) (n = 1019), carotid intima-media thickness (IMT) (n = 578), transmitral early-to-late left ventricular diastolic velocity (E/A) (n = 779) and estimated glomerular filtration rate (eGFR) (n = 1174). Independent of mean arterial <span class="hlt">pressure</span> and confounders, PPc, and both Pb and Pf were associated with end-organ measures or damage (P < 0.05 to P < 0.0001). With adjustments for brachial PP and confounders, Pb remained directly associated with LVMI (partial r = 0.09, P < 0.01), PWV (partial r = 0.28, P < 0.0001), and IMT (partial r = 0.28, P < 0.0001), and inversely associated with E/A (partial r = -0.31, P < 0.0001) and eGFR (partial r = -0.14, P < 0.0001). Similar relations were noted with the presence of end-organ damage (P < 0.05 to P < 0.0001). In contrast, with adjustments for brachial PP and confounders, Pf no longer retained direct relations with LVMI, PWV, and IMT or inverse relations with E/A and eGFR. Adjustments for Pb, but not Pf, diminished brachial PP-independent relationships between PPc and end-organ measures. Independent relations between Pb, but not Pf and end-organ measures, were largely attributed to Pb accounting for most of the variation in brachial-to-aortic PP amplification. In communities of African ancestry, brachial BP-independent relations between aortic <span class="hlt">pressure</span> and end-organ changes are largely attributed to an impact of reflected rather than forward <span class="hlt">wave</span> <span class="hlt">pressures</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006cosp...36..349B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006cosp...36..349B"><span>Studies of <span class="hlt">wave</span> phenomena using HF-<span class="hlt">induced</span> scatter target</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blagoveshchenskaya, N.; Borisova, T.; Kornienko, V.; Rietveld, M.; Frolov, V.; Uryadov, V.; Kagan, L.; Yampolski, Y.; Vertogradov, G.; Kelley, M.</p> <p></p> <p>Experimental results from Tromso and Sura heating experiments at high and mid-latitudes are examined It was shown that the combination of HF-<span class="hlt">induced</span> target and bi-static HF Doppler radio scatter observations is a profitable method for the identification and studies of <span class="hlt">wave</span> phenomena of different origin We analysed the ULF activity in the Pc 3-4 range and the medium-scale traveling ionospheric disturbances TIDs at high and mid-latitudes Bi-static HF Doppler radio scatter observations were carried out on the London-Tromso-St Petersburg path in the course of Tromso heating experiments During Sura heating experiments multi-position bi-static HF Doppler radio scatter observations were simultaneously performed at three reception points including St Petersburg Kharkov and Rostov-on-Don Ray tracing and Doppler shift simulations were made for all experiments Parameters of ULF <span class="hlt">waves</span> were found The interesting feature detected from Sura heating experiment was the dependence of the ULF <span class="hlt">wave</span> parameters from the effective radiated power of the heating facility Medium-scale TIDs were observed in the evening and pre-midnight hours TIDs in the auroral E region with periods of 20-25 min were traveling southward at speeds from 190-250 m s TIDs in the mid-latitudinal F region with periods from 15 to 45 min were at speeds between 40 and 120 m s During quiet magnetic conditions the <span class="hlt">waves</span> were traveling in the north-east direction In disturbed conditions the <span class="hlt">waves</span> were moving in the south-west direction with higher speeds as compared with quiet conditions Possible mechanisms</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19720026553&hterms=Vibrations+waves&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DVibrations%2Bwaves','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19720026553&hterms=Vibrations+waves&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DVibrations%2Bwaves"><span>The vibration of a box-type structure. II - Response to a travelling <span class="hlt">pressure</span> <span class="hlt">wave</span>.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Popplewell, N.</p> <p>1971-01-01</p> <p>A finite element method is formulated for determining the transient response of a box-type structure to a traveling, arbitrarily shaped <span class="hlt">pressure</span> <span class="hlt">wave</span>. The method is illustrated by considering an example of practical concern - the sonic boom. The acceleration-time histories of a closed box are compared with those obtained experimentally from a simulated boom. Satisfactory agreement is obtained with only four rectangular elements per individual face and a simplified loading of the box.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA551992','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA551992"><span>Relationship between Orientation to a Blast and <span class="hlt">Pressure</span> <span class="hlt">Wave</span> Propagation Inside the Rat Brian</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2011-01-01</p> <p>generated during an explosion may result in brain damage anll related neuro- logical impairments. Several mechanisms by which the primary blast <span class="hlt">wave</span> can...CSF). to the central nervous system. To address a basic question related to the mechanisms of blast brain injury. <span class="hlt">pressure</span> was measured inside the...can damage the bra in have been pro- posed, includi ng: ( 1) mechanical displacement of brain resulting in contusions and hemorrhages and direct</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23732346','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23732346"><span>Relationship between P <span class="hlt">wave</span> dispersion, left ventricular mass index and blood <span class="hlt">pressure</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chávez, Elibet; González, Emilio; Llanes, María Del C; Garí, Merlin; García, Yosvany; García Sáez, Julieta</p> <p>2013-06-01</p> <p>The study of arterial hypertension risk factors in children guarantees the establishment of health policies to avoid complications associated with this illness in the future. The highest values of P-<span class="hlt">wave</span> dispersion during sinus rhythm are pointed as predictors of atrial fibrillation in adulthood since there is an association between arterial hypertension, P-<span class="hlt">wave</span> dispersion and left ventricular hypertrophy. The aim of this study was to determine the relationship between blood <span class="hlt">pressure</span>, left ventricular mass index and P-<span class="hlt">wave</span> dispersion in the pediatric population. In the frame of the PROCDEC II project, children from 8 to 11 years old, without known heart conditions were studied. Arterial blood <span class="hlt">pressure</span> was measured in all the children; a 12-lead surface ECG and an echocardiogram were done as well. Left ventricular mass index mean values for normotensive (25.21 ± 5.96 g/m²) and hypertensive (30.38 ± 7.39 g/m²) children showed significant differences (p= 0.000). The mean value of the left atrial area was significantly different (p= 0.000) when comparing prehypertensive (10.98 ± 2.23 cm2) and hypertensive (12.21 ± 1.27 cm²) children to normotensive ones (10.66 ± 2.38 cm²). The correlation of P-<span class="hlt">wave</span> dispersion and the left ventricular mass index showed an r= 0.87 and p= 0.000. P-<span class="hlt">wave</span> dispersion is increased in pre- and hypertensive children compared to normotensive ones. A dependence of the P-<span class="hlt">wave</span> dispersion of the left ventricular mass index was found in hypertensive children.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25322237','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25322237"><span>Underwater blast <span class="hlt">wave</span> <span class="hlt">pressure</span> sensor based on polymer film fiber Fabry-Perot cavity.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Junjie; Wang, Meng; Xu, Jian; Peng, Li; Yang, Minghong; Xia, Minghe; Jiang, Desheng</p> <p>2014-10-01</p> <p>This paper describes the theoretical and experimental aspects of an optical underwater shock <span class="hlt">wave</span> sensor based on a polymer film optical fiber Fabry-Perot cavity manufactured by vacuum deposition technology. The transduction mechanism of the sensor involves a normally incident acoustic stress <span class="hlt">wave</span> that changes the thickness of the polymer film, thereby giving rise to a phase shift. This transient interferometric phase is interrogated by a three-phase-step algorithm. Theoretically, the sensor-acoustic-field interaction principle is analyzed, and the phase modulation sensitivity based on the theory of <span class="hlt">waves</span> in the layered media is calculated. Experimentally, a static calibration test and a dynamic calibration test are conducted using a piston-type <span class="hlt">pressure</span> calibration machine and a focusing-type electromagnetic shock <span class="hlt">wave</span>. Results indicate that the repeatability, hysteresis, nonlinearity, and the overall measurement accuracy of the sensor within the full <span class="hlt">pressure</span> range of 55 MPa are 1.82%, 0.86%, 1.81%, and 4.49%, respectively. The dynamic response time is less than 0.767 μs. Finally, three aspects that need further study for practical use are pointed out.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3341626','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3341626"><span>RELATIONS BETWEEN DAIRY FOOD INTAKE AND ARTERIAL STIFFNESS: PULSE <span class="hlt">WAVE</span> VELOCITY AND PULSE <span class="hlt">PRESSURE</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Crichton, Georgina E.; Elias, Merrrill F.; Dore, Gregory A.; Abhayaratna, Walter P.; Robbins, Michael A.</p> <p>2012-01-01</p> <p>Modifiable risk factors, such as diet, are becomingly increasingly important in the management of cardiovascular disease, one of the greatest major causes of death and disease burden. Few studies have examined the role of diet as a possible means of reducing arterial stiffness, as measured by pulse <span class="hlt">wave</span> velocity, an independent predictor of cardiovascular events and all-cause mortality. The aim of this study was to investigate whether dairy food intake is associated with measures of arterial stiffness including carotid-femoral pulse <span class="hlt">wave</span> velocity and pulse <span class="hlt">pressure</span>. A cross-sectional analysis of a subset of the Maine Syracuse Longitudinal Study sample was performed. A linear decrease in pulse <span class="hlt">wave</span> velocity was observed across increasing intakes of dairy food consumption (ranging from never/rarely to daily dairy food intake). The negative linear relationship between pulse <span class="hlt">wave</span> velocity and intake of dairy food was independent of demographic variables, other cardiovascular disease risk factors and nutrition variables. The pattern of results was very similar for pulse <span class="hlt">pressure</span>, while no association between dairy food intake and lipid levels was found. Further intervention studies are needed to ascertain whether dairy food intake may be an appropriate dietary intervention for the attenuation of age-related arterial stiffening and reduction of cardiovascular disease risk. PMID:22431583</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815523B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815523B"><span>Eruptive Source Parameters from Near-Source Gravity <span class="hlt">Waves</span> <span class="hlt">Induced</span> by Large Vulcanian eruptions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barfucci, Giulia; Ripepe, Maurizio; De Angelis, Silvio; Lacanna, Giorgio; Marchetti, Emanuele</p> <p>2016-04-01</p> <p>The sudden ejection of hot material from volcanic vent perturbs the atmosphere generating a broad spectrum of <span class="hlt">pressure</span> oscillations from acoustic infrasound (<10 Hz) to gravity <span class="hlt">waves</span> (<0.03 Hz). However observations of gravity <span class="hlt">waves</span> excited by volcanic eruptions are still rare, mostly limited to large sub-plinian eruptions and frequently at large distance from the source (>100 km). Atmospheric Gravity <span class="hlt">waves</span> are <span class="hlt">induced</span> by perturbations of the hydrostatic equilibrium of the atmosphere and propagate within a medium with internal density stratification. They are initiated by mechanisms that cause the atmosphere to be displaced as for the injection of volcanic ash plume during an eruption. We use gravity <span class="hlt">waves</span> to infer eruptive source parameters, such as mass eruption rate (MER) and duration of the eruption, which may be used as inputs in the volcanic ash transport and dispersion models. We present the analysis of near-field observations (<7 km) of atmospheric gravity <span class="hlt">waves</span>, with frequencies of 0.97 and 1.15 mHz, recorded by a <span class="hlt">pressure</span> sensors network during two explosions in July and December 2008 at Soufrière Hills Volcano, Montserrat. We show that gravity <span class="hlt">waves</span> at Soufrière Hills Volcano originate above the volcanic dome and propagate with an apparent horizontal velocities of 8-10 m/s. Assuming a single mass injection point source model, we constrain the source location at ~3.5 km a.s.l., above the vent, duration of the gas thrust < 140 s and MERs of 2.6 and 5.4 x10E7 kg/s, for the two eruptive events. Source duration and MER derived by modeling Gravity <span class="hlt">Waves</span> are fully compatible with others independent estimates from field observations. Our work strongly supports the use of gravity <span class="hlt">waves</span> to model eruption source parameters and can have a strong impact on our ability to monitor volcanic eruption at a large distance and may have future application in assessing the relative magnitude of volcanic explosions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5869021','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5869021"><span>Finite element analysis of the shock <span class="hlt">waves</span> <span class="hlt">induced</span> in the liquid wall of a pellet fusion reactor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Miya, K.; Iizuka, T.; Silverman, J.</p> <p>1985-01-01</p> <p>A shock <span class="hlt">wave</span> <span class="hlt">induced</span> in liquid metal is analyzed numerically by application of the finite element method. Since the governing equations of motion of the fluid are nonlinear, an incremental method is combined with the finite element method to obtain a convergent solution of the shock <span class="hlt">wave</span> without an interaction technique. To demonstrate the validity of the method developed, shock <span class="hlt">wave</span> problems in an inertial confinement spherical reactor with a liquid lithium ''waterfall'' are solved for two cases of surface heating due to soft x-ray absorption and bulk heating due to 14-MeV neutron absorption. The solution is based on a combination of the conservation equations for mass, energy, and momentum along with the following equation of state for liquid metals: p = P /sub b/ ((/rho///rho//sub 0/) /sup n/ - 1). Numerical results show that peak <span class="hlt">pressure</span> <span class="hlt">induced</span> in the liquid lithium is very high even for a comparatively small energy release E /sub TAU/ = 100 MJ/microexplosion of a pellet. Dynamic stress <span class="hlt">induced</span> in a 5-cm-thick stainless steel <span class="hlt">pressure</span> vessel is 1.14 x 10/sup 3/ MPa for the surface heating. The results show that the dynamic stress <span class="hlt">induced</span> by bulk heating is superimposed on that due to surface heating within the same period. Two appropriate ways to reduce the high stress are application of two-phase flow of liquid lithium or an increase in the thickness of the <span class="hlt">pressure</span> vessel.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21546961','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21546961"><span>Generation of a 400 GPa <span class="hlt">pressure</span> in water using converging strong shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fedotov-Gefen, A.; Efimov, S.; Gilburd, L.; Bazalitski, G.; Gurovich, V. Tz.; Krasik, Ya. E.</p> <p>2011-06-15</p> <p>Results related to the generation of an extreme state of water with <span class="hlt">pressure</span> up to (4.3 {+-} 0.2){center_dot}10{sup 11} Pa, density up to 4.2 {+-} 0.1 g/cm{sup 3}, and temperature up to 2.2 {+-} 0.1 eV in the vicinity of the implosion axis of a converging strong shock <span class="hlt">wave</span> are reported. The shock <span class="hlt">wave</span> was produced by the underwater electrical explosion of a cylindrical Cu wire array. A {approx}8 kJ pulse generator with a current amplitude {<=}550 kA and rise time of 350 ns was used to explode arrays having varying lengths, radii, and number of wires. Hydrodynamic numerical simulations coupled to the experimental data of the shock <span class="hlt">wave</span> propagation in water, rate of energy deposition into the array, and light emission from the compressed water in the vicinity of the implosion axis were used to determine the <span class="hlt">pressure</span>, density, and temperature profiles during the implosion. Results of a comparison between these parameters obtained with the SESAME and quantum molecular dynamics data bases of equation of state for water are reported as well. Also, the dependences of the maximal <span class="hlt">pressure</span> in the vicinity of the implosion axes on the array radius and the deposited energy density per unit length are reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhPl...18f2701F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhPl...18f2701F"><span>Generation of a 400 GPa <span class="hlt">pressure</span> in water using converging strong shock <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fedotov-Gefen, A.; Efimov, S.; Gilburd, L.; Bazalitski, G.; Gurovich, V. Tz.; Krasik, Ya. E.</p> <p>2011-06-01</p> <p>Results related to the generation of an extreme state of water with <span class="hlt">pressure</span> up to (4.3 ± 0.2).1011 Pa, density up to 4.2 ± 0.1 g/cm3, and temperature up to 2.2 ± 0.1 eV in the vicinity of the implosion axis of a converging strong shock <span class="hlt">wave</span> are reported. The shock <span class="hlt">wave</span> was produced by the underwater electrical explosion of a cylindrical Cu wire array. A ˜8 kJ pulse generator with a current amplitude ≤550 kA and rise time of 350 ns was used to explode arrays having varying lengths, radii, and number of wires. Hydrodynamic numerical simulations coupled to the experimental data of the shock <span class="hlt">wave</span> propagation in water, rate of energy deposition into the array, and light emission from the compressed water in the vicinity of the implosion axis were used to determine the <span class="hlt">pressure</span>, density, and temperature profiles during the implosion. Results of a comparison between these parameters obtained with the SESAME and quantum molecular dynamics data bases of equation of state for water are reported as well. Also, the dependences of the maximal <span class="hlt">pressure</span> in the vicinity of the implosion axes on the array radius and the deposited energy density per unit length are reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1510517P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1510517P"><span>Topographically <span class="hlt">induced</span> <span class="hlt">waves</span> in a pycnocline: internal solitary <span class="hlt">waves</span> and trapped orographic <span class="hlt">waves</span> in the Toulouse stratified water flume</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paci, Alexandre; Dossmann, Yvan; Auclair, Francis; Colin, Jeanne; Johnson, Ted; Lacaze, Laurent; Cid, Emmanuel</p> <p>2013-04-01</p> <p>The Meteo-France and CNRS geophysical fluid dynamics laboratory located in Toulouse (French meteorological service research center CNRM-GAME, UMR3589) provides facilities for fundamental and applied study of homogeneous, stratified and/or rotating flows. The research activities of the team focus on atmospheric boundary layers and internal gravity <span class="hlt">waves</span>. Two recent experiments related to topographically <span class="hlt">induced</span> internal gravity <span class="hlt">waves</span> are presented here. The Toulouse stratified water flume is a unique facility to study neutral or stratified flows (e.g. [1]). It has been specially designed to generate accurate and exhaustive datasets on flows similar to the atmospheric or oceanic ones under perfectly controlled conditions. It is thus a good extension of field experiments which are limited by the fact that data are scattered and conditions are not well controlled. This 30 m long, 3 m wide and 1.6 m deep density-stratified water flume can also be operated as a towing tank filled with water or with density-stratified brines. Experiments have been recently carried out in order to investigate internal solitary <span class="hlt">waves</span> generated over an oceanic ridge in a configuration close to the one used by Dossmann et al. 2011 ([2]), but in a much larger tank. These <span class="hlt">waves</span> are quite frequent in some areas, and can have a strong impact on sea structures (e.g. offshore platform). They also influence the oceanic dynamics and are difficult to parameterize. An extensive dataset has been collected on <span class="hlt">waves</span> generated in a pycnocline by direct interaction of a barotropic tide with a ridge (primary generation) and by an internal <span class="hlt">wave</span> beam generated over a ridge impinging on a pycnocline (secondary generation). Various flow regimes have been observed, including soliton and train of solitons. Another set of experiments (see [3] and [4]) deals with trapped orographic <span class="hlt">waves</span> generated over an isolated mountain. These experiments have been inspired by a theoretical model which predicts the structure of</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4344573','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4344573"><span>Black Tea Lowers Blood <span class="hlt">Pressure</span> and <span class="hlt">Wave</span> Reflections in Fasted and Postprandial Conditions in Hypertensive Patients: A Randomised Study</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Grassi, Davide; Draijer, Richard; Desideri, Giovambattista; Mulder, Theo; Ferri, Claudio</p> <p>2015-01-01</p> <p>Hypertension and arterial stiffening are independent predictors of cardiovascular mortality. Flavonoids may exert some vascular protection. We investigated the effects of black tea on blood <span class="hlt">pressure</span> (BP) and <span class="hlt">wave</span> reflections before and after fat load in hypertensives. According to a randomized, double-blind, controlled, cross-over design, 19 patients were assigned to consume black tea (129 mg flavonoids) or placebo twice a day for eight days (13 day wash-out period). Digital volume pulse and BP were measured before and 1, 2, 3 and 4 h after tea consumption. Measurements were performed in a fasted state and after a fat load. Compared to placebo, reflection index and stiffness index decreased after tea consumption (p < 0.0001). Fat challenge increased <span class="hlt">wave</span> reflection, which was counteracted by tea consumption (p < 0.0001). Black tea decreased systolic and diastolic BP (−3.2 mmHg, p < 0.005 and −2.6 mmHg, p < 0.0001; respectively) and prevented BP increase after a fat load (p < 0.0001). Black tea consumption lowers <span class="hlt">wave</span> reflections and BP in the fasting state, and during the challenging haemodynamic conditions after a fat load in hypertensives. Considering lipemia-<span class="hlt">induced</span> impairment of arterial function may occur frequently during the day, our findings suggest regular consumption of black tea may be relevant for cardiovascular protection. PMID:25658240</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18378271','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18378271"><span>Shock <span class="hlt">wave</span> emission from laser-<span class="hlt">induced</span> cavitation bubbles in polymer solutions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Brujan, Emil-Alexandru</p> <p>2008-09-01</p> <p>The role of extensional viscosity on the acoustic emission from laser-<span class="hlt">induced</span> cavitation bubbles in polymer solutions and near a rigid boundary is investigated by acoustic measurements. The polymer solutions consist of a 0.5% polyacrylamide (PAM) aqueous solution with a strong elastic component and a 0.5% carboxymethylcellulose (CMC) aqueous solution with a weak elastic component. A reduction of the maximum amplitude of the shock <span class="hlt">wave</span> <span class="hlt">pressure</span> and a prolongation of the oscillation period of the bubble were found in the elastic PAM solution. It might be caused by an increased resistance to extensional flow which is conferred upon the liquid by the polymer additive. In both polymer solutions, however, the shock <span class="hlt">pressure</span> decays proportionally to r(-1) with increasing distance r from the emission centre.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996SPIE.2681..437H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996SPIE.2681..437H"><span>Shock <span class="hlt">wave</span> and cavitation bubble measurements of ultrashort-pulse laser-<span class="hlt">induced</span> breakdown in water</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hammer, Daniel X.; Thomas, Robert J.; Frenz, Martin; Jansen, E. Duco; Noojin, Gary D.; Diggs, Sarah J.; Noack, Joachim; Vogel, Alfred; Rockwell, Benjamin A.</p> <p>1996-05-01</p> <p>Laser-<span class="hlt">induced</span> breakdown (LIB) has long been used in ophthalmic microsurgery as a mechanism for disruption of tissue. The goal of this surgery has been precise tissue cutting by plasma formation and a minimization of collateral damage due to shock <span class="hlt">wave</span> and cavitation bubble formation. We investigate the strength of the shock <span class="hlt">wave</span> emission, the size of the cavitation bubble, and the amount of plasma shielding to determine the efficacy of using femtosecond pulses in surgery to reduce collateral photoacoustic damage. A pump-probe technique is used to image the time-resolved evolution of the cavitation bubble produced by focused laser pulses with pulsewidths of 130 fs, 300 fs, 3 ps, and 60 ps. Simultaneously, a hydrophone is used to measure the <span class="hlt">pressure</span> response generated by the initial plasma shock <span class="hlt">wave</span> and subsequent shock <span class="hlt">waves</span> generated by the collapse and rebound of the cavitation bubbles. In addition, transmission measurements are made which indicate the amount of energy shielded beyond the focus by the plasma. These measurements give a good indication of the degree to which collateral damage may be reduced as the pulsewidths is decreased from the picosecond to the femtosecond time regime.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14986411','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14986411"><span><span class="hlt">Pressure</span> <span class="hlt">wave</span> propagation in fluid-filled co-axial elastic tubes. Part 2: Mechanisms for the pathogenesis of syringomyelia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carpenter, P W; Berkouk, K; Lucey, A D</p> <p>2003-12-01</p> <p>Our aim in this paper is to use a simple theoretical model of the intraspinal cerebrospinal-fluid system to investigate mechanisms proposed for the pathogenesis of syringomyelia. The model is based on an inviscid theory for the propagation of <span class="hlt">pressure</span> <span class="hlt">waves</span> in co-axial, fluid-filled, elastic tubes. According to this model, the leading edge of a <span class="hlt">pressure</span> pulse tends to steepen and form an elastic jump, as it propagates up the intraspinal cerebrospinal-fluid system. We show that when an elastic jump is incident on a stenosis of the spinal subarachnoid space, it reflects to form a transient, localized region of high <span class="hlt">pressure</span> within the spinal cord that for a cough-<span class="hlt">induced</span> pulse is estimated to be 50 to 70 mm Hg or more above the normal level in the spinal subarachnoid space. We propose this as a new mechanism whereby <span class="hlt">pressure</span> pulses created by coughing or sneezing can generate syrinxes. We also use the same analysis to investigate Williams' suck mechanism. Our results do not support his concept, nor, in cases where the stenosis is severe, the differential-<span class="hlt">pressure</span>-propagation mechanism recently proposed by Greitz et al. Our analysis does provide some support for the piston mechanism recently proposed by Oldfield et al. and Heiss et al. For instance, it shows clearly how the spinal cord is compressed by the formation of elastic jumps over part of the cardiac cycle. What appears to be absent for this piston mechanism is any means whereby the elastic jumps can be focused (e.g., by reflecting from a stenosis) to form a transient, localized region of high <span class="hlt">pressure</span> within the spinal cord. Thus it would seem to offer a mechanism for syrinx progression, but not for its formation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ChPhL..29f0509H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ChPhL..29f0509H"><span>Non-Rational Rogue <span class="hlt">Waves</span> <span class="hlt">Induced</span> by Inhomogeneity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>He, Jing-Song; Wang, You-Ying; Li, Lin-Jing</p> <p>2012-06-01</p> <p>The variable Sine—Gordon (VSG) equation is often used to model several kinds of systems with inhomogeneity and it can be realized by the management of dispersion and nonlinearity in optics and Feschbach resonance in Bose-Einstein condensates. We derive four new kinds of non-rational rogue <span class="hlt">wave</span> (RW) of the VSG by using an explicit transformation and the designable integrability. These RWs have novel profiles and interesting internal structures. It is shown that the RW is <span class="hlt">induced</span> by the inhomogeneity of the system modeled by the VSG. The theoretical prediction of the corresponding relations between the RWs and some extreme events in DNA is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19800045672&hterms=shocking&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dshocking','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800045672&hterms=shocking&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dshocking"><span>Interaction of laser-<span class="hlt">induced</span> stress <span class="hlt">waves</span> with metals</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Clauer, A. H.; Fairand, B. P.</p> <p>1979-01-01</p> <p>An investigation of the effect of high intensity laser <span class="hlt">induced</span> stress <span class="hlt">waves</span> on the hardness and tensile strength of 2024 and 7075 aluminum and on the fatigue properties of 7075 aluminum were investigated. Laser shocking increases the hardness of the underaged 2024-T351 but has little or no effect on the peak aged 2024-T351 and 7075-T651 or the overaged 7075-T73. The fretting fatigue life of fastener joints of 7075-T6 was increased by orders of magnitude by laser shocking the region around the fastener hole; the fatigue crack propagation rates were decreased by laser shocking.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApPhL.111k4101L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApPhL.111k4101L"><span>Plasma-<span class="hlt">induced</span> flow instabilities in atmospheric <span class="hlt">pressure</span> plasma jets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lietz, Amanda M.; Johnsen, Eric; Kushner, Mark J.</p> <p>2017-09-01</p> <p>Pulsed plasma excitation of rare gases flowing into air has been shown to impact the stability of the flow in non-equilibrium atmospheric <span class="hlt">pressure</span> plasma jets (APPJs). In this paper, the results from a numerical modeling investigation of the stability of a round He APPJ with a powered electrode exposed to the gas flow are discussed. Localized gas heating at the powered electrode occurs on the time scale of the voltage pulse, tens to 100 ns, which is short compared to the fluid timescales. An acoustic <span class="hlt">wave</span> propagates from this heated, expanding gas and exits the jet. The <span class="hlt">wave</span> disturbs the shear layer between the He and surrounding humid air, exciting a shear instability which grows downstream with the flow and increases the mixing of the humid air into the He. The effects of the eddy-dominated flow on ionization <span class="hlt">wave</span> (IW) propagation in an APPJ were investigated. The IW followed the regions of the highest helium concentration, resulting in an increased production of NO, HO2, and NO2.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23232414','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23232414"><span>Shear <span class="hlt">wave</span> <span class="hlt">induced</span> resonance elastography of venous thrombi: a proof-of-concept.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schmitt, Cédric; Montagnon, Emmanuel; Henni, Anis Hadj; Qi, Shijie; Cloutier, Guy</p> <p>2013-03-01</p> <p>Shear <span class="hlt">wave</span> <span class="hlt">induced</span> resonance elastography (SWIRE) is proposed for deep venous thrombosis (DVT) elasticity assessment. This new imaging technique takes advantage of properly polarized shear <span class="hlt">waves</span> to <span class="hlt">induce</span> resonance of a confined mechanical heterogeneity. Realistic phantoms (n = 9) of DVT total and partial clot occlusions with elasticities from 406 to 3561 Pa were built for in vitro experiments. An ex vivo study was also performed to evaluate the elasticity of two fresh porcine venous thrombi in a pig model. Transient shear <span class="hlt">waves</span> at 45-205 Hz were generated by the vibration of a rigid plate (plane wavefront) or by a needle to simulate a radiation <span class="hlt">pressure</span> on a line segment (cylindrical wavefront). <span class="hlt">Induced</span> propagation of shear <span class="hlt">waves</span> was imaged with an ultrafast ultrasound scanner and a finite element method was developed to simulate tested experimental conditions. An inverse problem was then formulated considering the first resonance frequency of the DVT inclusion. Elasticity agreements between SWIRE and a reference spectroscopy instrument (RheoSpectris) were found in vitro for total clots either in plane (r(2) = 0.989) or cylindrical (r(2) = 0.986) wavefront configurations. For total and partial clots, elasticity estimation errors were 9.0 ±4.6% and 9.3 ±11.3%, respectively. Ex vivo, the blood clot elasticity was 498 ±58 Pa within the inferior vena cava and 436 ±45 Pa in the right common iliac vein (p = 0.22). To conclude, the SWIRE technique seems feasible to quantitatively assess blood clot elasticity in the context of DVT ultrasound imaging.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRA..121.9771C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRA..121.9771C"><span>Van Allen Probes observations of electromagnetic ion cyclotron <span class="hlt">waves</span> triggered by enhanced solar wind dynamic <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cho, J.-H.; Lee, D.-Y.; Noh, S.-J.; Shin, D.-K.; Hwang, J.; Kim, K.-C.; Lee, J. J.; Choi, C. R.; Thaller, S.; Skoug, R.</p> <p>2016-10-01</p> <p>Magnetospheric compression due to impact of enhanced solar wind dynamic <span class="hlt">pressure</span> Pdyn has long been considered as one of the generation mechanisms of electromagnetic ion cyclotron (EMIC) <span class="hlt">waves</span>. With the Van Allen Probe-A observations, we identify three EMIC <span class="hlt">wave</span> events that are triggered by Pdyn enhancements under prolonged northward interplanetary magnetic field (IMF) quiet time preconditions. They are in contrast to one another in a few aspects. Event 1 occurs in the middle of continuously increasing Pdyn while Van Allen Probe-A is located outside the plasmapause at postmidnight and near the equator (magnetic latitude (MLAT) -3°). Event 2 occurs by a sharp Pdyn pulse impact while Van Allen Probe-A is located inside the plasmapause in the dawn sector and rather away from the equator (MLAT 12°). Event 3 is characterized by amplification of a preexisting EMIC <span class="hlt">wave</span> by a sharp Pdyn pulse impact while Van Allen Probe-A is located outside the plasmapause at noon and rather away from the equator (MLAT -15°). These three events represent various situations where EMIC <span class="hlt">waves</span> can be triggered by Pdyn increases. Several common features are also found among the three events. (i) The strongest <span class="hlt">wave</span> is found just above the He+ gyrofrequency. (ii) The <span class="hlt">waves</span> are nearly linearly polarized with a rather oblique propagation direction ( 28° to 39° on average). (iii) The proton fluxes increase in immediate response to the Pdyn impact, most significantly in tens of keV energy, corresponding to the proton resonant energy. (iv) The temperature anisotropy with T⊥ > T|| is seen in the resonant energy for all the events, although its increase by the Pdyn impact is not necessarily always significant. The last two points (iii) and (iv) may imply that in addition to the temperature anisotropy, the increase of the resonant protons must have played a critical role in triggering the EMIC <span class="hlt">waves</span> by the enhanced Pdyn impact.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JaJAP..41.3316H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JaJAP..41.3316H"><span>Visualization and Measurements of Sound <span class="hlt">Pressure</span> Distribution of Ultrasonic <span class="hlt">Wave</span> by Stroboscopic Real-Time Holographic Interferometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hisada, Shigeyoshi; Suzuki, Takahiro; Nakahara, Sumio; Fujita, Takeyoshi</p> <p>2002-05-01</p> <p>The sound <span class="hlt">pressure</span> distribution of underwater ultrasonic <span class="hlt">waves</span> is measured by real-time stroboscope holographic interferometry using bismuth silicon oxide single crystal. Stroboscopic sub-microsecond irradiation of laser light enables the recording of the stationary holographic interferogram of refractive index changes of water by ultrasonic <span class="hlt">waves</span> for the frame time of a charge coupled device camera. The fringe order distribution is calculated from the interferogram by Fourier transform fringe analysis. The optical path differences caused by sound field along the optical path are converted into local field values of sound <span class="hlt">pressure</span>, which is displayed as a gray scale distribution image. In the experiment, the sound <span class="hlt">pressure</span> distributions of ultrasonic <span class="hlt">waves</span> through rectangular and circular apertures are observed. They are compared with the theoretical sound <span class="hlt">pressure</span> distribution. The sound <span class="hlt">pressure</span> values obtained by a hydrophone show good agreement with the measured values obtained by this method. The converging and diverging sound <span class="hlt">pressure</span> fields realized by an acoustic lens are measured.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ExFl...57..179H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ExFl...57..179H"><span>Optical-flow-based background-oriented schlieren technique for measuring a laser-<span class="hlt">induced</span> underwater shock <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hayasaka, Keisuke; Tagawa, Yoshiyuki; Liu, Tianshu; Kameda, Masaharu</p> <p>2016-12-01</p> <p>The background-oriented schlieren (BOS) technique with the physics-based optical flow method (OF-BOS) is developed for measuring the <span class="hlt">pressure</span> field of a laser-<span class="hlt">induced</span> underwater shock <span class="hlt">wave</span>. Compared to BOS with the conventional cross-correlation method that is also applied for particle image velocimetry (here called PIV-BOS), by using the OF-BOS, the displacement field generated by a small density gradient in water can be obtained at the spatial resolution of one vector per pixel. The corresponding density and <span class="hlt">pressure</span> fields can be further extracted. It is demonstrated in particular that the sufficiently high spatial resolution of the extracted displacement vector field is required in the tomographic reconstruction to correctly infer the <span class="hlt">pressure</span> field of the spherical underwater shock <span class="hlt">wave</span>. The capability of the OF-BOS method is critically evaluated based on synchronized hydrophone measurements. Special emphasis is placed on direct comparison between the OF-BOS and PIV-BOS methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002ASAJ..112.2240T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002ASAJ..112.2240T"><span>Radiation <span class="hlt">pressure</span> of standing <span class="hlt">waves</span> on liquid columns and small diffusion flames</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thiessen, David B.; Marr-Lyon, Mark J.; Wei, Wei; Marston, Philip L.</p> <p>2002-11-01</p> <p>The radiation <span class="hlt">pressure</span> of standing ultrasonic <span class="hlt">waves</span> in air is demonstrated in this investigation to influence the dynamics of liquid columns and small flames. With the appropriate choice of the acoustic amplitude and wavelength, the natural tendency of long columns to break because of surface tension was suppressed in reduced gravity [M. J. Marr-Lyon, D. B. Thiessen, and P. L. Marston, Phys. Rev. Lett. 86, 2293-2296 (2001); 87(20), 9001(E) (2001)]. Evaluation of the radiation force shows that narrow liquid columns are attracted to velocity antinodes. The response of a small vertical diffusion flame to ultrasonic radiation <span class="hlt">pressure</span> in a horizontal standing <span class="hlt">wave</span> was observed in normal gravity. In agreement with our predictions of the distribution of ultrasonic radiation stress on the flame, the flame is attracted to a <span class="hlt">pressure</span> antinode and becomes slightly elliptical with the major axis in the plane of the antinode. The radiation <span class="hlt">pressure</span> distribution and the direction of the radiation force follow from the dominance of the dipole scattering for small flames. Understanding radiation stress on flames is relevant to the control of hot fluid objects. [Work supported by NASA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011APS..GECNR3008X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011APS..GECNR3008X"><span>Simulation of High <span class="hlt">Pressure</span> Ionization <span class="hlt">Waves</span> in Straight and Circuitous Dielectric Channels</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xiong, Zhongmin; Takashima, Keisuke; Adamovich, Igor V.; Kushner, Mark J.</p> <p>2011-10-01</p> <p>High <span class="hlt">pressure</span> non-equilibrium plasmas are often transient and in the form of fast ionization <span class="hlt">waves</span> (FIWs) with applications from plasma assisted combustion to plasma medicine. A numerical study of FIWs, with comparison to experiments, was conducted using nonPDPSIM, a 2-d plasma hydrodynamics model with radiation transport. We first investigated the fundamental properties of moderate <span class="hlt">pressure</span> FIWs in straight dielectric channels to quantify their propagation mechanisms. The FIWs were generated by ns high voltage pulses in N2 and He at <span class="hlt">pressures</span> of 10-20 Torr. Simulations are compared to experiments for transient electric fields and <span class="hlt">wave</span> speed. The effects of the secondary emission properties of bounding surfaces on plasma uniformity will be discussed. We then applied these results to a study of the propagation of FIWs in Ne at atmospheric <span class="hlt">pressure</span> through long, circuitous channels (length > 15 cm, width < 1 mm) as used to deliver plasma to remote sites. The FIW speed and front structure for positive and negative polarities, and the effects of channel curvature and dielectric constants of the channel wall on FIW dynamics will be discussed. Work is supported by the DOE Office of Fusion Energy Science.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/8350814','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/8350814"><span><span class="hlt">Pressure</span> <span class="hlt">wave</span> generated by the passage of a heavy charged particle in water.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sun, Y Y; Nath, R</p> <p>1993-01-01</p> <p>Energy deposition around the trajectories of ionizing particles with linear energy transfer (LET) of 4, 40, and 400 keV/microns in water and subsequent diffusion of deposited heat is calculated using computational fluid dynamics. Immediately after the deposition of energy by the charged particle, the temperature and <span class="hlt">pressure</span> in the vicinity of the particle track both increase dramatically, leading to the formation of a thermal spike and a <span class="hlt">pressure</span> <span class="hlt">wave</span>. Initially, the region of heat deposition is primarily localized to a region called the "thermal core," which has dimensions of 0.3, 1, and 3 nm for particles with LETs of 4, 40, and 400 keV/microns, respectively. Instantaneous peak temperatures within the thermal core were 800 degrees C-2000 degrees C and peak <span class="hlt">pressures</span> were about 25,000 atm. This sudden deposition of heat in a localized region leads to a very strong shock <span class="hlt">wave</span> around the particle trajectory, which is shown to last for a duration of 10(-9)-10(-8) s. Even at distances beyond 10 nm away from the particle trajectory, <span class="hlt">pressures</span> above 100 atm could exist for a duration of up to 10(-11) s. This local and transient environment, created by the passage of a charged particle in a medium, may lead to new mechanisms of radiation action leading to cell damage, as well as to the development of new radiation detectors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvB..92m4102L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvB..92m4102L"><span>Atomistic pathways of the <span class="hlt">pressure-induced</span> densification of quartz</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liang, Yunfeng; Miranda, Caetano R.; Scandolo, Sandro</p> <p>2015-10-01</p> <p>When quartz is compressed at room temperature it retains its crystal structure at <span class="hlt">pressures</span> well above its stability domain (0-2 GPa), and collapses into denser structures only when <span class="hlt">pressure</span> reaches 20 GPa. Depending on the experimental conditions, <span class="hlt">pressure-induced</span> densification can be accompanied by amorphization; by the formation of crystalline, metastable polymorphs; and can be preceded by the appearance of an intermediate phase, quartz II, with unknown structure. Based on molecular dynamic simulations, we show that this rich phenomenology can be rationalized through a unified theoretical framework of the atomistic pathways leading to densification. The model emphasizes the role played by the oxygen sublattice, which transforms from a bcc-like order in quartz into close-packed arrangements in the denser structures, through a ferroelastic instability of martensitic nature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26574522','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26574522"><span>Carbon dioxide <span class="hlt">pressure-induced</span> coagulation of microalgae.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Roland; Jessop, Philip G; Champagne, Pascale</p> <p>2015-12-28</p> <p>The move to a low-carbon economy has generated renewed interest in microalgae for the production of biofuels with the potential mutual benefit of wastewater treatment. However, harvesting has been identified as a limiting factor to the economic viability of this process. This paper explores the harvesting of microalgae using high-<span class="hlt">pressure</span> gas without the addition of coagulants. Coagulation of microalgae under high-<span class="hlt">pressure</span> gas was found to be an efficient method to separate algae from suspension. The critical coagulation <span class="hlt">pressures</span> (CCPs) for H(2) and CO(2) were determined to be 6.1 and 6.2 MPa, respectively. The CO(2)-<span class="hlt">induced</span> decrease in solution pH positively influenced coagulation rates, without appearing to affect the CCP. This approach could be beneficial for the economic removal of microalgae from solution for the production of both biofuels and biomedical compounds without the addition of non-environmentally friendly chemicals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvE..95a2601P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvE..95a2601P"><span>Kinetics of motility-<span class="hlt">induced</span> phase separation and swim <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Patch, Adam; Yllanes, David; Marchetti, M. Cristina</p> <p>2017-01-01</p> <p>Active Brownian particles (ABPs) represent a minimal model of active matter consisting of self-propelled spheres with purely repulsive interactions and rotational noise. Here we examine the <span class="hlt">pressure</span> of ABPs in two dimensions in both closed boxes and systems with periodic boundary conditions and show that its nonmonotonic behavior with density is a general property of ABPs and is not the result of finite-size effects. We correlate the time evolution of the mean <span class="hlt">pressure</span> towards its steady-state value with the kinetics of motility-<span class="hlt">induced</span> phase separation. For parameter values corresponding to phase-separated steady states, we identify two dynamical regimes. The <span class="hlt">pressure</span> grows monotonically in time during the initial regime of rapid cluster formation, overshooting its steady-state value and then quickly relaxing to it, and remains constant during the subsequent slower period of cluster coalescence and coarsening. The overshoot is a distinctive feature of active systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005EL.....69..556S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005EL.....69..556S"><span><span class="hlt">Pressure-induced</span> homothetic volume collapse in silicon clathrates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>San Miguel, A.; Merlen, A.; Toulemonde, P.; Kume, T.; LeFloch, S.; Aouizerat, A.; Pascarelli, S.; Aquilanti, G.; Mathon, O.; LeBihan, T.; Itié, J.-P.; Yamanaka, S.</p> <p>2005-02-01</p> <p>The high-<span class="hlt">pressure</span> properties of the Ba-doped silicon clathrate Ba8Si46 have been investigated combining X-ray diffraction and X-ray absorption spectroscopy. A <span class="hlt">pressure-induced</span> isostructural phase transition associated with an important volume collapse takes place at 11.5 14 GPa. This transformation is characterized by the homothetic contraction of the silicon cages containing the Ba atoms. This transition is preceded by a change in the electronic structure at 5 GPa in good agreement with Raman spectroscopy observations (T. Kume et al., Phys. Rev. Lett., 90 (2003) 155503) that it is also of isostructural nature. The cage structure is preserved through the phase transitions allowing to obtain tetrahedral silicon with record interatomic distances as low as 2.13 Å. At the highest studied <span class="hlt">pressure</span> of 49 GPa, the structure becomes irreversibly amorphous. The physical origin of the homothetic isostructural transitions is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JHyd..544..467S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JHyd..544..467S"><span>Two-dimensional vertical moisture-<span class="hlt">pressure</span> dynamics above groundwater <span class="hlt">waves</span>: Sand flume experiments and modelling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shoushtari, Seyed Mohammad Hossein Jazayeri; Cartwright, Nick; Perrochet, Pierre; Nielsen, Peter</p> <p>2017-01-01</p> <p>This paper presents a new laboratory dataset on the moisture-<span class="hlt">pressure</span> relationship above a dispersive groundwater <span class="hlt">wave</span> in a two-dimensional vertical unconfined sand flume aquifer driven by simple harmonic forcing. A total of five experiments were conducted in which all experimental parameters were kept constant except for the oscillation period, which ranged from 268 s to 2449 s between tests. Moisture content and suction head sensor pairings were co-located at two locations in the unsaturated zone both approximately 0.2 m above the mean watertable elevation and respectively 0.3 m and 0.75 m from the driving head boundary. For all oscillation periods except for the shortest (T = 268s), the formation of a hysteretic moisture-<span class="hlt">pressure</span> scanning loop was observed. Consistent with the decay of the saturated zone groundwater <span class="hlt">wave</span>, the size of the observed moisture-<span class="hlt">pressure</span> scanning loops decayed with increasing distance landward and the decay rate is larger for the shorter oscillation periods. At the shortest period (T = 268s), the observed moisture-<span class="hlt">pressure</span> relationship was observed to be non-hysteretic but with a capillary capacity that differs from that of the static equilibrium wetting and drying curves. This finding is consistent with observations from existing one-dimensional vertical sand column experiments. The relative damping of the moisture content with distance landward is higher than that for the suction head consistent with the fact that transmission of <span class="hlt">pressure</span> through a porous medium occurs more readily than mass transfer. This is further supported by the fact that observed phase lags for the unsaturated zone variables (i.e. suction head and moisture content) relative to the driving head are greater than the saturated zone variables (i.e. piezometric head). Harmonic analysis of the data reveals no observable generation of higher harmonics in either moisture or <span class="hlt">pressure</span> despite the strongly non-linear relationship between the two. In addition, a phase lag</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997PhFl....9.2716D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997PhFl....9.2716D"><span>Coherent vortex model for surface <span class="hlt">pressure</span> fluctuations <span class="hlt">induced</span> by the wall region of a turbulent boundary layer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dhanak, Manhar R.; Dowling, Ann P.; Si, Chao</p> <p>1997-09-01</p> <p>Exact solutions of the Navier-Stokes equations describing the interaction of streamwise vortices with a rigid surface are utilized to develop a conceptual model for the surface <span class="hlt">pressure</span> spectrum associated with the wall region of a turbulent boundary layer. The evolution of single as well as pairs of coherent streamwise vortices, which principally govern the production of turbulence in the wall region, is considered in the presence of local straining flow <span class="hlt">induced</span> by larger, outer-layer eddies. The surface <span class="hlt">pressure</span> signatures of the coherent vortex motion and the associated power spectrum of the <span class="hlt">pressure</span> are examined. Based on the results of the exact solutions, the surface <span class="hlt">pressure</span> spectrum of an ensemble of independent coherent structures is modeled using the assumption of ergodicity in the manner described by Townsend and Lundgren for homogeneous turbulence. The free parameters in the model are estimated through comparison with available results from experiments and numerical simulations. The model, especially the one involving pairs of streamwise vortices, predicts the high frequency and high spanwise <span class="hlt">wave</span> number range of the surface <span class="hlt">pressure</span> spectrum quite well. Further, the probability density function of surface <span class="hlt">pressure</span> associated with the model compares well with experimental results. Interestingly, the model also suggests that the contribution of the viscous interaction to low <span class="hlt">wave</span> number spectral elements accounts for the discrepancy between experimental observations at such <span class="hlt">wave</span> numbers and the prediction of the Kraichnan-Phillips theorem.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27376406','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27376406"><span><span class="hlt">Pressure-induced</span> exotic states in rare earth hexaborides.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sun, Liling; Wu, Qi</p> <p>2016-08-01</p> <p>Finding the exotic phenomena in strongly correlated electron systems (SCESs) and understanding the corresponding microphysics have long been the research frontiers of condensed matter physics. The remarkable examples for the intriguing phenomena discovered in past years include unconventional superconductivity, heavy Fermion behaviors, giant magneto-resistance and so on. A fascinating type of rare earth hexaboride RB6 (R  =  Sm, Yb, Eu and Ce) belongs to a strongly correlated electron system (SCES), but shows unusual ambient-<span class="hlt">pressure</span> and high-<span class="hlt">pressure</span> behaviors beyond the phenomena mentioned above. Particularly, the recent discovery of the coexistence of an unusual metallic surface state and an insulating bulk state in SmB6, known to be a Kondo insulator decades ago, by theoretical calculations and many experimental measurements creates new interest for the investigation of the RB6. This significant progress encourages people to revisit the RB6 with an attempt to establish a new physics that links the SCES and the unusual metallic surface state which is a common feature of a topological insulator (TI). It is well known that <span class="hlt">pressure</span> has the capability of tuning the electronic structure and modifying the ground state of solids, or even <span class="hlt">inducing</span> a quantum phase transition which is one of the kernel issues in studies of SCESs. In this brief review, we will describe the progress in high <span class="hlt">pressure</span> studies on the RB6 based on our knowledge and research interests, mainly focusing on the <span class="hlt">pressure-induced</span> phenomena in YbB6 and SmB6, especially on the quantum phase transitions and their connections with the valence state of the rare earth ions. Moreover, some related high-<span class="hlt">pressure</span> results obtained from CeB6 and EuB6 are also included. Finally, a summary is given in the conclusions and perspectives section.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JChPh.138i4506T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JChPh.138i4506T"><span><span class="hlt">Pressure-induced</span> phase transition and polymerization of tetracyanoethylene (TCNE)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tomasino, Dane; Chen, Jing-Yin; Kim, Minesob; Yoo, Choong-Shik</p> <p>2013-03-01</p> <p>We have studied the <span class="hlt">pressure-induced</span> physical and chemical transformations of tetracyanoethylene (TCNE or C6N4) in diamond anvil cells using micro-Raman spectroscopy, laser-heating, emission spectroscopy, and synchrotron x-ray diffraction. The results indicate that TCNE in a quasi-hydrostatic condition undergoes a shear-<span class="hlt">induced</span> phase transition at 10 GPa and then a chemical change to two-dimensional (2D) C=N polymers above 14 GPa. These phase and chemical transformations depend strongly on the state of stress in the sample and occur sluggishly in non-hydrostatic conditions over a large <span class="hlt">pressure</span> range between 7 and 14 GPa. The x-ray diffraction data indicate that the phase transition occurs isostructurally within the monoclinic structure (P21/c) without any apparent volume discontinuity and the C=N polymer is highly disordered but remains stable to 60 GPa—the maximum <span class="hlt">pressure</span> studied. On the other hand, laser-heating of the C=N polymer above 25 GPa further converts to a theoretically predicted 3D C-N network structure, evident from an emergence of new Raman νs(C-N) at 1404 cm-1 at 25 GPa and the visual appearance of translucent solid. The C-N product is, however, unstable upon <span class="hlt">pressure</span> unloading below 10 GPa, resulting in a grayish powder that can be considered as nano-diamonds with high-nitrogen content at ambient <span class="hlt">pressure</span>. The C-N product shows a strong emission line centered at 640 nm at 30 GPa, which linearly shifts toward shorter wavelength at the rate of -1.38 nm/GPa. We conjecture that the observed red shift upon unloading <span class="hlt">pressure</span> is due to increase of defects in the C-N product and thereby weakening of C-N bonds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016RPPh...79h4503S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016RPPh...79h4503S"><span><span class="hlt">Pressure-induced</span> exotic states in rare earth hexaborides</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Liling; Wu, Qi</p> <p>2016-08-01</p> <p>Finding the exotic phenomena in strongly correlated electron systems (SCESs) and understanding the corresponding microphysics have long been the research frontiers of condensed matter physics. The remarkable examples for the intriguing phenomena discovered in past years include unconventional superconductivity, heavy Fermion behaviors, giant magneto-resistance and so on. A fascinating type of rare earth hexaboride RB6 (R  =  Sm, Yb, Eu and Ce) belongs to a strongly correlated electron system (SCES), but shows unusual ambient-<span class="hlt">pressure</span> and high-<span class="hlt">pressure</span> behaviors beyond the phenomena mentioned above. Particularly, the recent discovery of the coexistence of an unusual metallic surface state and an insulating bulk state in SmB6, known to be a Kondo insulator decades ago, by theoretical calculations and many experimental measurements creates new interest for the investigation of the RB6. This significant progress encourages people to revisit the RB6 with an attempt to establish a new physics that links the SCES and the unusual metallic surface state which is a common feature of a topological insulator (TI). It is well known that <span class="hlt">pressure</span> has the capability of tuning the electronic structure and modifying the ground state of solids, or even <span class="hlt">inducing</span> a quantum phase transition which is one of the kernel issues in studies of SCESs. In this brief review, we will describe the progress in high <span class="hlt">pressure</span> studies on the RB6 based on our knowledge and research interests, mainly focusing on the <span class="hlt">pressure-induced</span> phenomena in YbB6 and SmB6, especially on the quantum phase transitions and their connections with the valence state of the rare earth ions. Moreover, some related high-<span class="hlt">pressure</span> results obtained from CeB6 and EuB6 are also included. Finally, a summary is given in the conclusions and perspectives section.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15002349','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15002349"><span><span class="hlt">Pressure</span> <span class="hlt">Wave</span> Measurements During Thermal Explosion of HMX-Based High Explosives</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Forbes, J W; Garcia, F; Tarver, C M; Urtiew, P A; Greenwood, D W; Vandersall, K S</p> <p>2002-06-27</p> <p>Five different experiments on thermal heating of explosive materials have been performed. Three experiments thermally exploded PBX 9501 (HMX/Estane/BDNPA-F; 9512.512.5 wt %) donor charges while two others thermally exploded LX-04 (HMX/Viton A; 85/15 wt %). These donor charges were encased in 304 stainless steel. The transmitted two-dimensional <span class="hlt">pressure</span> <span class="hlt">waves</span> were measured by gauges in acceptor cylinders of Teflon, PBX 9501, or LX-04 that were in contact with the donors' steel case. A fifth experiment measured the <span class="hlt">pressure</span> in an acceptor charge of PBX 9501 that had a 100 mm stand-off from the top of the steel case of the thermally cooked off PBX 9501 donor charge. Reactive flow hydrodynamic modeling using a rapid deflagration velocity of approximately 500 m/s was able to reproduce the <span class="hlt">pressure</span> gauge records for both the in contact and stand off experiments that used PBX 9501 donors and acceptors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21424133','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21424133"><span>[Vertigo <span class="hlt">induced</span> by noise or <span class="hlt">pressure</span> to the left ear].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Seidel, D U; Dülks, A; Remmert, S</p> <p>2011-06-01</p> <p>A 49-year-old male patient presented with recently acquired vertigo <span class="hlt">induced</span> by noise or <span class="hlt">pressure</span> to the left ear. With appropriate stimulation, oscillopsia with a rotatory component could be reproduced in videooculography. Cervical vestibular evoked myogenic potentials (VEMP) showed increased amplitudes and a lowered threshold on the left side. CT of the petrous bone showed a bony dehiscence of the left superior semicircular canal. Conservative therapy was initiated as a first step.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24413772','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24413772"><span>Dickkopf-3 attenuates <span class="hlt">pressure</span> overload-<span class="hlt">induced</span> cardiac remodelling.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Yan; Liu, Yu; Zhu, Xue-Hai; Zhang, Xiao-Dong; Jiang, Ding-Sheng; Bian, Zhou-Yan; Zhang, Xiao-Fei; Chen, Ke; Wei, Xiang; Gao, Lu; Zhu, Li-Hua; Yang, Qinglin; Fan, Guo-Chang; Lau, Wayne B; Ma, Xinliang; Li, Hongliang</p> <p>2014-04-01</p> <p>Dickkopf-3 (DKK3), a secreted protein in the Dickkopf family, is expressed in various tissues, including the heart, and has been shown to play an important role in tissue development. However, the biological function of DKK3 in the heart remains largely unexplored. This study aimed to examine the role of DKK3 in pathological cardiac hypertrophy. We performed gain-of-function and loss-of-function studies using DKK3 cardiac-specific transgenic (TG) mice and DKK3 knockout (KO) mice (C57BL/6J background). Cardiac hypertrophy was <span class="hlt">induced</span> by aortic banding. Cardiac hypertrophy was evaluated by echocardiographic, haemodynamic, pathological, and molecular analyses. Our results demonstrated that the loss of DKK3 exaggerated <span class="hlt">pressure</span> overload-<span class="hlt">induced</span> cardiac hypertrophy, fibrosis, and dysfunction, whereas the overexpression of DKK3 protected the heart against <span class="hlt">pressure</span> overload-<span class="hlt">induced</span> cardiac remodelling. These beneficial effects were associated with the inhibition of the ASK1-JNK/p38 (apoptosis signal-regulating kinase 1-c-Jun N-terminal kinase/p38) signalling cascade. Parallel in vitro experiments confirmed these in vivo observations. Co-immunoprecipitation experiments suggested that physical interactions occurred between DKK3 and ASK1. Moreover, rescue experiments indicated that, in DKK3 TG mice, the activation of ASK1 using a cardiac-specific conditional ASK1 transgene reduced the functionality of DKK3 in response to <span class="hlt">pressure</span> overload; furthermore, the inactivation of ASK1 by dominant-negative ASK1 rescued <span class="hlt">pressure</span> overload-<span class="hlt">induced</span> cardiac abnormalities in DKK3 KO mice. Taken together, our findings indicate that DKK3 acts as a cardioprotective regulator of pathological cardiac hypertrophy and that this function largely occurs via the regulation of ASK1-JNK/p38 signalling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012APS..MARQ52011R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012APS..MARQ52011R"><span>Geometry-<span class="hlt">induced</span> rigidity in <span class="hlt">pressurized</span> elastic shells</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reis, Pedro; Florijn, Bastiaan; Lazarus, Arnaud</p> <p>2012-02-01</p> <p>We study the indentation of <span class="hlt">pressurized</span> thin elastic shells, with positive Gauss curvature. In our precision desktop-scale experiments, the geometry of the shells and their material properties are custom-controlled using rapid prototyping and digital fabrication techniques. The mechanical response is quantified through load-displacement compression tests and the differential <span class="hlt">pressure</span> is set by a syringe-pump system under feedback control. Focus is given to the linear regime of the response towards quantifying the geometry-<span class="hlt">induced</span> rigidity of <span class="hlt">pressurized</span> shells with different shapes. We find that this effective stiffness is proportional to the local mean curvature in the neighborhood of the locus of indentation. Combining classic theory of shells with recent developments by D. Vella et al. (2011), we rationalize the dependence of the geometry-<span class="hlt">induced</span> rigidity on: i) the mean curvature at the point of indentation, ii) the material properties of the shell and iii) the in-out differential <span class="hlt">pressure</span>. The proposed predictive framework is in excellent agreement with our experiments, over a wide range of control parameters. The prominence of geometry in this class of problems points to the relevance and applicability of our results over a wide range of lengthscales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17825347','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17825347"><span><span class="hlt">Wave</span> aberrations in rhesus monkeys with vision-<span class="hlt">induced</span> ametropias.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ramamirtham, Ramkumar; Kee, Chea-Su; Hung, Li-Fang; Qiao-Grider, Ying; Huang, Juan; Roorda, Austin; Smith, Earl L</p> <p>2007-09-01</p> <p>The purpose of this study was to investigate the relationship between refractive errors and high-order aberrations in infant rhesus monkeys. Specifically, we compared the monochromatic <span class="hlt">wave</span> aberrations measured with a Shack-Hartman wavefront sensor between normal monkeys and monkeys with vision-<span class="hlt">induced</span> refractive errors. Shortly after birth, both normal monkeys and treated monkeys reared with optically <span class="hlt">induced</span> defocus or form deprivation showed a decrease in the magnitude of high-order aberrations with age. However, the decrease in aberrations was typically smaller in the treated animals. Thus, at the end of the lens-rearing period, higher than normal amounts of aberrations were observed in treated eyes, both hyperopic and myopic eyes and treated eyes that developed astigmatism, but not spherical ametropias. The total RMS wavefront error increased with the degree of spherical refractive error, but was not correlated with the degree of astigmatism. Both myopic and hyperopic treated eyes showed elevated amounts of coma and trefoil and the degree of trefoil increased with the degree of spherical ametropia. Myopic eyes also exhibited a much higher prevalence of positive spherical aberration than normal or treated hyperopic eyes. Following the onset of unrestricted vision, the amount of high-order aberrations decreased in the treated monkeys that also recovered from the experimentally <span class="hlt">induced</span> refractive errors. Our results demonstrate that high-order aberrations are influenced by visual experience in young primates and that the increase in high-order aberrations in our treated monkeys appears to be an optical byproduct of the vision-<span class="hlt">induced</span> alterations in ocular growth that underlie changes in refractive error. The results from our study suggest that the higher amounts of <span class="hlt">wave</span> aberrations observed in ametropic humans are likely to be a consequence, rather than a cause, of abnormal refractive development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24613560','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24613560"><span><span class="hlt">Pressure</span> <span class="hlt">waves</span> in neurons and their relationship to tangled neurons and plaques.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Barz, Helmut; Barz, Ulrich</p> <p>2014-05-01</p> <p>The paper based on the hypothesis that mechanical impulses cause the transmission of excitement in the peripheral and central nervous system. Possible connections between changes in the tubular neuronal network and the morphological findings of Alzheimer's disease are presented. Additionally, changes in the viscosity of the neuronal cytoplasm and changes in the walls of the neuronal fibers due to the intracellular hydrostatic <span class="hlt">pressure</span> and <span class="hlt">pressure</span> <span class="hlt">waves</span> are considered possible causes of plaques, threads and tangles. The <span class="hlt">pressure</span> causes reduced elasticity and mechanical breakdown in neuronal fiber walls. This is compared to features found in blood vessels. It is presumed that damaged membranes lead to an escape of cytoplasm from the neurons into the extracellular space. This outflow may cause the spherical structured proteinaceous plaques. On the other hand it could be that the decrease of fluid and reduced intraneuronal <span class="hlt">pressure</span> after a membrane crack may favor the agglomeration of cytoplasm proteins in the neurons forming threads and tangles. The consolidation of the neuronal cytoplasm and the irreparable decrement of the intracellular <span class="hlt">pressure</span> cause a loss of function and finally a dieback of the affected neurons. The reduction of blood perfusion due to an increased local tissue <span class="hlt">pressure</span> in certain regions of the brain may promote the forming of Alzheimer deposits. An increase of preamyloid proteins and small soluble amyloid particles within the extracellular fluid can lead, along their natural drainage route, to an amyloid angiopathy. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4291638','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4291638"><span>Transdermal deferoxamine prevents <span class="hlt">pressure-induced</span> diabetic ulcers</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Duscher, Dominik; Neofytou, Evgenios; Wong, Victor W.; Maan, Zeshaan N.; Rennert, Robert C.; Januszyk, Michael; Rodrigues, Melanie; Malkovskiy, Andrey V.; Whitmore, Arnetha J.; Galvez, Michael G.; Whittam, Alexander J.; Brownlee, Michael; Rajadas, Jayakumar; Gurtner, Geoffrey C.</p> <p>2015-01-01</p> <p>There is a high mortality in patients with diabetes and severe <span class="hlt">pressure</span> ulcers. For example, chronic <span class="hlt">pressure</span> sores of the heels often lead to limb loss in diabetic patients. A major factor underlying this is reduced neovascularization caused by impaired activity of the transcription factor hypoxia <span class="hlt">inducible</span> factor-1 alpha (HIF-1α). In diabetes, HIF-1α function is compromised by a high glucose-<span class="hlt">induced</span> and reactive oxygen species-mediated modification of its coactivator p300, leading to impaired HIF-1α transactivation. We examined whether local enhancement of HIF-1α activity would improve diabetic wound healing and minimize the severity of diabetic ulcers. To improve HIF-1α activity we designed a transdermal drug delivery system (TDDS) containing the FDA-approved small molecule deferoxamine (DFO), an iron chelator that increases HIF-1α transactivation in diabetes by preventing iron-catalyzed reactive oxygen stress. Applying this TDDS to a <span class="hlt">pressure-induced</span> ulcer model in diabetic mice, we found that transdermal delivery of DFO significantly improved wound healing. Unexpectedly, prophylactic application of this transdermal delivery system also prevented diabetic ulcer formation. DFO-treated wounds demonstrated increased collagen density, improved neovascularization, and reduction of free radical formation, leading to decreased cell death. These findings suggest that transdermal delivery of DFO provides a targeted means to both prevent ulcer formation and accelerate diabetic wound healing with the potential for rapid clinical translation. PMID:25535360</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25535360','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25535360"><span>Transdermal deferoxamine prevents <span class="hlt">pressure-induced</span> diabetic ulcers.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Duscher, Dominik; Neofytou, Evgenios; Wong, Victor W; Maan, Zeshaan N; Rennert, Robert C; Inayathullah, Mohammed; Januszyk, Michael; Rodrigues, Melanie; Malkovskiy, Andrey V; Whitmore, Arnetha J; Walmsley, Graham G; Galvez, Michael G; Whittam, Alexander J; Brownlee, Michael; Rajadas, Jayakumar; Gurtner, Geoffrey C</p> <p>2015-01-06</p> <p>There is a high mortality in patients with diabetes and severe <span class="hlt">pressure</span> ulcers. For example, chronic <span class="hlt">pressure</span> sores of the heels often lead to limb loss in diabetic patients. A major factor underlying this is reduced neovascularization caused by impaired activity of the transcription factor hypoxia <span class="hlt">inducible</span> factor-1 alpha (HIF-1α). In diabetes, HIF-1α function is compromised by a high glucose-<span class="hlt">induced</span> and reactive oxygen species-mediated modification of its coactivator p300, leading to impaired HIF-1α transactivation. We examined whether local enhancement of HIF-1α activity would improve diabetic wound healing and minimize the severity of diabetic ulcers. To improve HIF-1α activity we designed a transdermal drug delivery system (TDDS) containing the FDA-approved small molecule deferoxamine (DFO), an iron chelator that increases HIF-1α transactivation in diabetes by preventing iron-catalyzed reactive oxygen stress. Applying this TDDS to a <span class="hlt">pressure-induced</span> ulcer model in diabetic mice, we found that transdermal delivery of DFO significantly improved wound healing. Unexpectedly, prophylactic application of this transdermal delivery system also prevented diabetic ulcer formation. DFO-treated wounds demonstrated increased collagen density, improved neovascularization, and reduction of free radical formation, leading to decreased cell death. These findings suggest that transdermal delivery of DFO provides a targeted means to both prevent ulcer formation and accelerate diabetic wound healing with the potential for rapid clinical translation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989aiaa.meetS....M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989aiaa.meetS....M"><span>Shock-<span class="hlt">wave-induced</span> mixing enhancement in scramjet combustors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Menon, S.</p> <p>1989-01-01</p> <p>An experimental study of the interaction between a weak shock <span class="hlt">wave</span> and a supersonic shear layer was carried out to determine the possibility of shock-<span class="hlt">induced</span> mixing enhancement. A supersonic (Mach 2.5) stream of nitrogen was mixed with a sonic helium jet downstream of a rearward-facing step to simulate the mixing region in the vicinity of a SCRAMJET flameholder. A small wedge was used to generate an oblique shock <span class="hlt">wave</span> that impinges on the mixing layer. Schlieren flow visualization and Rayleigh scattering concentration measurements were carried out. The results indicate that significant spreading of the shear layer may occur downstream of the shock/shear layer interaction region. Further study is required to determine the mechanism of the observed spreading and the extent of the increase in mixing efficiency. Since there are shock-<span class="hlt">induced</span> losses, an optimum mixing enhancement configuration will have to be determined before the method can be validated and successfully implemented in a SCRAMJET combustor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4286758','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4286758"><span>Artificial magnetic field <span class="hlt">induced</span> by an evanescent <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mochol, Małgorzata; Sacha, Krzysztof</p> <p>2015-01-01</p> <p>Cold atomic gases are perfect laboratories for realization of quantum simulators. In order to simulate solid state systems in the presence of magnetic fields special effort has to be made because atoms are charge neutral. There are different methods for realization of artificial magnetic fields, that is the creation of specific conditions so that the motion of neutral particles mimics the dynamics of charged particles in an effective magnetic field. Here, we consider adiabatic motion of atoms in the presence of an evanescent <span class="hlt">wave</span>. Theoretical description of the adiabatic motion involves artificial vector and scalar potentials related to the Berry phases. Due to the large gradient of the evanescent field amplitude, the potentials can be strong enough to <span class="hlt">induce</span> measurable effects in cold atomic gases. We show that the resulting artificial magnetic field is able to <span class="hlt">induce</span> vortices in a Bose-Einstein condensate trapped close to a surface of a prism where the evanescent <span class="hlt">wave</span> is created. We also analyze motion of an atomic cloud released from a magneto-optical trap that falls down on the surface of the prism. The artificial magnetic field is able to reflect falling atoms that can be observed experimentally. PMID:25567430</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22279941','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22279941"><span>Observable spectra of <span class="hlt">induced</span> gravitational <span class="hlt">waves</span> from inflation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Alabidi, Laila; Sasaki, Misao; Kohri, Kazunori; Sendouda, Yuuiti E-mail: kohri@post.kek.jp E-mail: sendouda@cc.hirosaki-u.ac.jp</p> <p>2012-09-01</p> <p>Measuring the primordial power spectrum on small scales is a powerful tool in inflation model building, yet constraints from Cosmic Microwave Background measurements alone are insufficient to place bounds stringent enough to be appreciably effective. For the very small scale spectrum, those which subtend angles of less than 0.3 degrees on the sky, an upper bound can be extracted from the astrophysical constraints on the possible production of primordial black holes in the early universe. A recently discovered observational by-product of an enhanced power spectrum on small scales, <span class="hlt">induced</span> gravitational <span class="hlt">waves</span>, have been shown to be within the range of proposed space based gravitational <span class="hlt">wave</span> detectors; such as NASA's LISA and BBO detectors, and the Japanese DECIGO detector. In this paper we explore the impact such a detection would have on models of inflation known to lead to an enhanced power spectrum on small scales, namely the Hilltop-type and running mass models. We find that the Hilltop-type model can produce observable <span class="hlt">induced</span> gravitational <span class="hlt">waves</span> within the range of BBO and DECIGO for integral and fractional powers of the potential within a reasonable number of e−folds. We also find that the running mass model can produce a spectrum within the range of these detectors, but require that inflation terminates after an unreasonably small number of e−folds. Finally, we argue that if the thermal history of the Universe were to accomodate such a small number of e−folds the Running Mass Model can produce Primordial Black Holes within a mass range compatible with Dark Matter, i.e. within a mass range 10{sup 20}g∼<M{sub BH}∼<10{sup 27}g.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JAP...113c3511Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JAP...113c3511Z"><span><span class="hlt">Pressure-induced</span> series of phase transitions in sodium azide</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhu, Hongyang; Zhang, Fuxiang; Ji, Cheng; Hou, Dongbin; Wu, Jianzhe; Hannon, Trevor; Ma, Yangzhang</p> <p>2013-01-01</p> <p>The phase analysis of sodium azide (NaN3) has been investigated by in situ synchrotron X-ray diffraction measurements in a diamond anvil cell up to 52.0 GPa at room temperature. Three <span class="hlt">pressure-induced</span> phase transitions were observed. The phase transition <span class="hlt">pressures</span> were determined to be 0.3, 17.3, and 28.7 GPa verified by three different <span class="hlt">pressure</span> transmitting media. The first high <span class="hlt">pressure</span> phase, α-NaN3 (0.3 ˜ 17.3 GPa), was identified to be monoclinic with a C2/m space group. The β-NaN3 to α-NaN3 transition is a second-order phase transition, accompanied by the shearing of the Na-layers and the tilting of the azide chains. The second high <span class="hlt">pressure</span> phase, γ-NaN3 (18.4 ˜ 28.7 GPa), has a lower symmetry than the α-NaN3. A further phase transition of γ-NaN3 to δ-NaN3 at 28.7 GPa was observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21504017','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21504017"><span><span class="hlt">Pressure</span> <span class="hlt">induced</span> reactions amongst calcium aluminate hydrate phases</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Moon, Ju-hyuk; Oh, Jae Eun; Balonis, Magdalena; Glasser, Fredrik P.; Clark, Simon M.; Monteiro, Paulo J.M.</p> <p>2011-06-15</p> <p>The compressibilities of two AFm phases (straetlingite and calcium hemicarboaluminate hydrate) and hydrogarnet were obtained up to 5 GPa by using synchrotron high-<span class="hlt">pressure</span> X-ray powder diffraction with a diamond anvil cell. The AFm phases show abrupt volume contraction regardless of the molecular size of the <span class="hlt">pressure</span>-transmitting media. This volume discontinuity could be associated to a structural transition or to the movement of the weakly bound interlayer water molecules in the AFm structure. The experimental results seem to indicate that the <span class="hlt">pressure-induced</span> dehydration is the dominant mechanism especially with hygroscopic <span class="hlt">pressure</span> medium. The Birch-Murnaghan equation of state was used to compute the bulk modulus of the minerals. Due to the discontinuity in the <span class="hlt">pressure</span>-volume diagram, a two stage bulk modulus of each AFm phase was calculated. The abnormal volume compressibility for the AFm phases caused a significant change to their bulk modulus. The reliability of this experiment is verified by comparing the bulk modulus of hydrogarnet with previous studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3312616','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3312616"><span>Over-<span class="hlt">Pressure</span> Suppresses Ultrasonic-<span class="hlt">Induced</span> Drug Uptake</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Stringham, S. Briant; Viskovska, Maria A.; Richardson, Eric S.; Ohmine, Seiga; Husseini, Ghaleb A.; Murray, Byron K.; Pitt, William G.</p> <p>2012-01-01</p> <p>Ultrasound (US) is used to enhance and target delivery of drugs and genes to cancer tissues. The present study further examines the role of acoustic cavitation in US-<span class="hlt">induced</span> permeabilization of cell membranes and subsequent drug or gene uptake by the cell. Rat colon cancer cells were exposed to ultrasound at various static <span class="hlt">pressures</span> to examine the hypothesis that oscillating bubbles, also known as cavitating bubbles, permeabilize cells. Increasing <span class="hlt">pressure</span> suppresses bubble cavitation activity; thus if applied <span class="hlt">pressure</span> were to reduce drug uptake, cell permeabilization would be strongly linked to bubble cavitation activity. Cells were exposed to 476 kHz pulsed ultrasound at average intensities of 2.75 W/cm2 and 5.5 W/cm2 at various <span class="hlt">pressures</span> and times in an isothermal chamber. Cell fractions with reversible membrane damage (calcein uptake) and irreversible damage (propidium iodide uptake) were analyzed by flow cytometry. <span class="hlt">Pressurization</span> to 3 atm nearly eliminated the biological effect of US in promoting calcein uptake. Data also showed a linear increase in membrane permeability based upon increased time and intensity. This research shows that US-mediated cell membrane permeability is likely linked to cavitation bubble activity. PMID:19056161</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16126811','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16126811"><span>Use of simultaneous <span class="hlt">pressure</span> and velocity measurements to estimate arterial <span class="hlt">wave</span> speed at a single site in humans.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Davies, Justin E; Whinnett, Zachary I; Francis, Darrel P; Willson, Keith; Foale, Rodney A; Malik, Iqbal S; Hughes, Alun D; Parker, Kim H; Mayet, Jamil</p> <p>2006-02-01</p> <p>It has not been possible to measure <span class="hlt">wave</span> speed in the human coronary artery, because the vessel is too short for the conventional two-point measurement technique used in the aorta. We present a new method derived from <span class="hlt">wave</span> intensity analysis, which allows derivation of <span class="hlt">wave</span> speed at a single point. We apply this method in the aorta and then use it to derive <span class="hlt">wave</span> speed in the human coronary artery for the first time. We measured simultaneous <span class="hlt">pressure</span> and Doppler velocity with intracoronary wires at the left main stem, left anterior descending and circumflex arteries, and aorta in 14 subjects after a normal coronary arteriogram. Then, in 10 subjects, serial measurements were made along the aorta before and after intracoronary isosorbide dinitrate. <span class="hlt">Wave</span> speed was derived by two methods in the aorta: 1) the two-site distance/time method (foot-to-foot delay of <span class="hlt">pressure</span> waveforms) and 2) a new single-point method using simultaneous <span class="hlt">pressure</span> and velocity measurements. Coronary <span class="hlt">wave</span> speed was derived by the single-point method. <span class="hlt">Wave</span> speed derived by the two methods correlated well (r = 0.72, P < 0.05). Coronary <span class="hlt">wave</span> speed correlated with aortic <span class="hlt">wave</span> speed (r = 0.72, P = 0.002). After nitrate administration, coronary <span class="hlt">wave</span> speed fell by 43%: from 16.4 m/s (95% confidence interval 12.6-20.1) to 9.3 m/s (95% confidence interval 6.5-12.0, P < 0.001). This single-point method allows determination of <span class="hlt">wave</span> speed in the human coronary artery. Aortic <span class="hlt">wave</span> speed is correlated to coronary <span class="hlt">wave</span> speed. Finally, this technique detects the prompt fall in coronary artery <span class="hlt">wave</span> speed with isosorbide dinitrate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19812454','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19812454"><span>Automated identification of peristaltic <span class="hlt">pressure</span> <span class="hlt">waves</span> in oesophageal manometry investigations using the rolling correlation technique.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Perring, S; Jones, E</p> <p>2009-11-01</p> <p>We have implemented the technique of rolling correlation coefficient as proposed by Buttfield and Bolton (2005 Real time measurement of RR intervals using a digital signal processor J. Med. Eng. Technol. 29 8-13) for ECG R-<span class="hlt">wave</span> detection in the detection and timing of oesophageal peristalsis. 43 sequential patients attending for oesophageal manometry were retrospectively reviewed. Two expert reviewers visually assessed each swallow for normality of peristaltic amplitude and propagation speed. Automatic assessment was performed using rolling correlation, maximum amplitude, threshold and maximum gradient techniques of identifying onset of peristalsis. Rolling correlation was comparable with the maximum amplitude technique at identifying peristaltic <span class="hlt">pressure</span> <span class="hlt">waves</span> visually identified as present. Rolling correlation was most effective at correctly identifying propagation velocity as normal (698 out of 845 normally propagating <span class="hlt">waves</span>) and highest correlation with expert visual assessment of percentage abnormal propagation for each patient (R value 0.918). In a sub-group of 11 studies assessed as displaying normal motility, rolling correlation gave lowest variation of propagation speed and highest consistency with visual assessment. The rolling correlation technique is effective and accurate at identifying oesophageal peristalsis and characterizing peristaltic propagation in manometric studies even in the presence of abnormally weak peristalsis and other confounding <span class="hlt">pressure</span> perturbations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27165882','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27165882"><span>The Correlation Between Intracranial <span class="hlt">Pressure</span> and Cerebral Blood Flow Velocity During ICP Plateau <span class="hlt">Waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lewis, Philip M; Smielewski, Peter; Rosenfeld, Jeffrey V; Pickard, John D; Czosnyka, Marek</p> <p>2016-01-01</p> <p>We previously showed that the flow-ICP index (Fix), a moving correlation coefficient between intracranial <span class="hlt">pressure</span> (ICP) and cerebral blood flow velocity (CBFV), had marginally greater prognostic value for patients with traumatic brain injury (TBI) than an index of cerebral autoregulation (mean index, Mx). The aim of this study was to further examine the clinical and physiological relevance of Fix by studying its behaviour during ICP plateau <span class="hlt">waves</span> in patients with TBI. Twenty-nine recordings of CBFV made during ICP plateau <span class="hlt">waves</span> were analysed. Both Mx and Fix at baseline and peak ICP were significantly different, although the magnitude of Fix change was slightly greater. The correlation between Fix and cerebral perfusion <span class="hlt">pressure</span> (CPP) was stronger than that between Mx and CPP. Unlike in our previous study, plotting Fix against CPP revealed a peak value in the range of "optimal" CPP, as indicated by the Mx versus CPP plot. The findings suggest that during periods of reduced CPP caused by plateau <span class="hlt">waves</span>, the dynamic behaviour of Fix is similar to that of a measure of cerebral autoregulation. This conclusion needs to be verified against similar results obtained during episodes of supranormal CPP.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SPIE10077E..0AS','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SPIE10077E..0AS"><span>Blood pulse <span class="hlt">wave</span> velocity and <span class="hlt">pressure</span> sensing via fiber based and free space based optical sensors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sirkis, Talia; Beiderman, Yevgeny; Agdarov, Sergey; Beiderman, Yafim; Zalevsky, Zeev</p> <p>2017-02-01</p> <p>Continuous noninvasive measurement of vital bio-signs, such as cardiopulmonary parameters, is an important tool in evaluation of the patient's physiological condition and health monitoring. On the demand of new enabling technologies, some works have been done in continuous monitoring of blood <span class="hlt">pressure</span> and pulse <span class="hlt">wave</span> velocity. In this paper, we introduce two techniques for non-contact sensing of vital bio signs. In the first approach the optical sensor is based on single mode in-fibers Mach-Zehnder interferometer (MZI) to detect heartbeat, respiration and pulse <span class="hlt">wave</span> velocity (PWV). The introduced interferometer is based on a new implanted scheme. It replaces the conventional MZI realized by inserting of discontinuities in the fiber to break the total internal reflection and scatter/collect light. The proposed fiber sensor was successfully incorporated into shirt to produce smart clothing. The measurements obtained from the smart clothing could be obtained in comfortable manner and there is no need to have an initial calibration or a direct contact between the sensor and the skin of the tested individual. In the second concept we show a remote noncontact blood pulse <span class="hlt">wave</span> velocity and <span class="hlt">pressure</span> measurement based on tracking the temporal changes of reflected secondary speckle patterns produced in human skin when illuminated by a laser beams. In both concept experimental validation of the proposed schemes is shown and analyzed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840025864&hterms=Atmospheric+pressure&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DAtmospheric%2Bpressure','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840025864&hterms=Atmospheric+pressure&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DAtmospheric%2Bpressure"><span>Experimental validation of a millimeter <span class="hlt">wave</span> radar technique to remotely sense atmospheric <span class="hlt">pressure</span> at the Earth's surface</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Flower, D. A.; Peckham, G. E.; Bradford, W. J.</p> <p>1984-01-01</p> <p>Experiments with a millimeter <span class="hlt">wave</span> radar operating on the NASA CV-990 aircraft which validate the technique for remotely sensing atmospheric <span class="hlt">pressure</span> at the Earth's surface are described. Measurements show that the precise millimeter <span class="hlt">wave</span> observations needed to deduce <span class="hlt">pressure</span> from space with an accuracy of 1 mb are possible, that sea surface reflection properties agree with theory and that the measured variation of differential absorption with altitude corresponds to that expected from spectroscopic models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhPl...24a3511W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhPl...24a3511W"><span>Modeling and simulations on the propagation characteristics of electromagnetic <span class="hlt">waves</span> in sub-atmospheric <span class="hlt">pressure</span> plasma slab</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Z. B.; Nie, Q. Y.; Li, B. W.; Kong, F. R.</p> <p>2017-01-01</p> <p>Sub-atmospheric <span class="hlt">pressure</span> plasma slabs exhibit the feature of relatively high plasma number density and high collisional frequency between electrons and neutral gases, as well as similar thickness to the electromagnetic (EM) wavelength in communication bands. The propagation characteristics of EM <span class="hlt">waves</span> in sub-atmospheric <span class="hlt">pressure</span> plasma slabs are attracting much attention of the researchers due to their applications in the plasma antenna, the blackout effect during reentry, <span class="hlt">wave</span> energy injection in the plasma, etc. In this paper, a numerical model with a one-dimensional assumption has been established and therefore, it is used for the investigations of the propagation characteristics of the EM <span class="hlt">waves</span> in plasma slabs. In this model, the EM <span class="hlt">waves</span> propagating in both sub-wavelength plasma slabs and plasmas with thicker slabs can be studied simultaneously, which is superior to the model with geometrical optics approximation. The influence of EM <span class="hlt">wave</span> frequencies and collisional frequencies on the amplitude of the transmitted EM <span class="hlt">waves</span> is discussed in typical plasma profiles. The results will be significant for deep understanding of the propagation behaviors of the EM <span class="hlt">waves</span> in sub-atmospheric <span class="hlt">pressure</span> nonuniform plasma slabs, as well as the applications of the interactions between EM <span class="hlt">waves</span> and the sub-atmospheric <span class="hlt">pressure</span> plasmas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JAP...118q3102W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JAP...118q3102W"><span>Experimental study on <span class="hlt">pressure</span>, stress state, and temperature-dependent dynamic behavior of shear thickening fluid subjected to laser <span class="hlt">induced</span> shock</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Xianqian; Yin, Qiuyun; Huang, Chenguang</p> <p>2015-11-01</p> <p>The dynamic response of the 57 vol./vol. % dense spherical silica particle-polyethylene glycol suspension at high <span class="hlt">pressure</span> was investigated through short pulsed laser <span class="hlt">induced</span> shock experiments by measuring the back free surface velocities of aluminum-shear thickening fluid (STF)-aluminum assembled targets. The results showed that the attenuation behavior of shock <span class="hlt">wave</span> in the STF was dependent on shock <span class="hlt">pressure</span>, stress state, and test temperature. The measured back free particle velocities of the targets and shock <span class="hlt">wave</span> velocities in the STF decreased with the decrease in shock <span class="hlt">pressure</span> while shocked at the same stress state and the same test temperature. In addition, two types of dragging mechanisms in the STF were observed while shocked at different stress states. For a uniaxial strain state, the impact <span class="hlt">induced</span> jamming behavior in the STF is the dragging mechanism for the attenuation of shock <span class="hlt">wave</span>, and a critical shock <span class="hlt">pressure</span> was required for the impact <span class="hlt">induced</span> thickening behavior. However, while the shock <span class="hlt">wave</span> transformed from a uniaxial strain state to a dilatation state after transmitted to a certain distance, beside the dragging effect of impact <span class="hlt">induced</span> jamming behavior, a strong dragging effect, <span class="hlt">induced</span> by shear <span class="hlt">induced</span> thickening behavior, was also observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1345846-ultrafast-laser-collision-induced-fluorescence-atmospheric-pressure-plasma','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1345846-ultrafast-laser-collision-induced-fluorescence-atmospheric-pressure-plasma"><span>Ultrafast laser-collision-<span class="hlt">induced</span> fluorescence in atmospheric <span class="hlt">pressure</span> plasma</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Barnat, E. V.; Fierro, A.</p> <p>2017-03-07</p> <p>The implementation and demonstration of laser-collision-<span class="hlt">induced</span> fluorescence (LCIF) generated in atmospheric <span class="hlt">pressure</span> helium environments is presented in this communication. As collision times are observed to be fast (~10 ns), ultrashort pulse laser excitation (<100 fs) of the 23S to 33P (388.9 nm) is utilized to initiate the LCIF process. Both neutral-<span class="hlt">induced</span> and electron-<span class="hlt">induced</span> components of the LCIF are observed in the helium afterglow plasma as the reduced electric field (E/N) is tuned from <0.1 Td to over 5 Td. Under the discharge conditions presented in this study (640 Torr He), the lower limit of electron density detection is ~1012 emore » cm-3. Lastly, the spatial profiles of the 23S helium metastable and electrons are presented as functions of E/N to demonstrate the spatial resolving capabilities of the LCIF method.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhD...50nLT01B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhD...50nLT01B"><span>Ultrafast laser-collision-<span class="hlt">induced</span> fluorescence in atmospheric <span class="hlt">pressure</span> plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barnat, E. V.; Fierro, A.</p> <p>2017-04-01</p> <p>The implementation and demonstration of laser-collision-<span class="hlt">induced</span> fluorescence (LCIF) generated in atmospheric <span class="hlt">pressure</span> helium environments is presented in this communication. As collision times are observed to be fast (~10 ns), ultrashort pulse laser excitation (<100 fs) of the 23S to 33P (388.9 nm) is utilized to initiate the LCIF process. Both neutral-<span class="hlt">induced</span> and electron-<span class="hlt">induced</span> components of the LCIF are observed in the helium afterglow plasma as the reduced electric field (E/N) is tuned from  <0.1 Td to over 5 Td. Under the discharge conditions presented in this study (640 Torr He), the lower limit of electron density detection is ~1012 e cm-3. The spatial profiles of the 23S helium metastable and electrons are presented as functions of E/N to demonstrate the spatial resolving capabilities of the LCIF method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ExFl...58...68C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ExFl...58...68C"><span>Impact <span class="hlt">pressure</span> and void fraction due to plunging breaking <span class="hlt">wave</span> impact on a 2D TLP structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chuang, Wei-Liang; Chang, Kuang-An; Mercier, Richard</p> <p>2017-06-01</p> <p>Violent impacts due to the plunging breaking <span class="hlt">wave</span> impingement on a 2D tension-leg platform (TLP) structure were experimentally investigated in a laboratory. Simultaneous <span class="hlt">pressure</span>, void fraction, fluid velocity, and structure motion measurements were performed on the multiphase, turbulent flow. The maximum mean impact <span class="hlt">pressure</span> is 2.3 ρC 2 with C being the <span class="hlt">wave</span> phase speed. The <span class="hlt">pressure</span> maximum and its rise time are negatively correlated, and the rise time for impulsive-type impacts is less than 15 ms or 0.18H/C with H being the <span class="hlt">wave</span> height. Different approaches show that impact coefficients vary from 0.6 to 9.7, including relating the impact <span class="hlt">pressure</span> maxima to the <span class="hlt">wave</span> phase speed, local velocity, and void fraction. By modeling the plunging breaking <span class="hlt">wave</span> impact as a filling flow, a <span class="hlt">pressure</span>-aeration relationship was investigated and compared with the approximate solution derived by Peregrine and Thais (J Fluid Mech 325:377-397, 1996). The measured data show that a high aeration level tends to reduce the impact <span class="hlt">pressure</span> maximum so the cushioning effect is significant for breaking <span class="hlt">wave</span> impacts on a moving vertical wall.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013OptLT..45..540F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013OptLT..45..540F"><span>Effects of the air <span class="hlt">pressure</span> on the <span class="hlt">wave</span>-packet dynamics of gaseous iodine molecules at room temperature</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fan, Rongwei; He, Ping; Chen, Deying; Xia, Yuanqin; Yu, Xin; Wang, Jialing; Jiang, Yugang</p> <p>2013-02-01</p> <p>Based on ultrafast laser pulses, time-resolved resonance enhancement coherent anti-Stokes Raman scattering (RE-CARS) is applied to investigate <span class="hlt">wave</span>-packet dynamics in gaseous iodine. The effects of air <span class="hlt">pressure</span> on the <span class="hlt">wave</span>-packet dynamics of iodine molecules are studied at <span class="hlt">pressures</span> ranging from 1.5 Torr to 750 Torr. The RE-CARS signals are recorded in a gas cell filled with a mixture of about 0.3 Torr iodine in air buffer gas at room temperature. The revivals and fractional revival structures in the <span class="hlt">wave</span>-packet signal are found to gradually disappear with rising air <span class="hlt">pressure</span> up to 750 Torr, and the decay behaviors of the excited B-state and ground X-state become faster with increasing air <span class="hlt">pressure</span>, which is due to the collision effects of the molecules and the growing complexity of the spectra at high <span class="hlt">pressures</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993JGR....98.9781R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993JGR....98.9781R"><span>Analysis of porous media heterogeneities using the diffusion of <span class="hlt">pressure</span> <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rigord, P.; Caristan, Y.; Hulin, J. P.</p> <p>1993-06-01</p> <p>We present an experimental study and a model of the diffusion of sinusoidal <span class="hlt">pressure</span> <span class="hlt">waves</span> through porous media. We show that measurements of the hydraulic admittance A(omega) in the sine <span class="hlt">wave</span> mode allow us to probe the structure of porous samples with an adjustable investigation depth depending on the frequency omega. The variations of A(omega) in heterogeneous media with a percolationlike geometry are modeled numerically on 2D percolation networks. One obtains a transition from normal diffusion at low frequencies to anomalous diffusion at higher frequencies. At the transition, the penetration depth of the <span class="hlt">wave</span> is of the order of the percolation correlation length. The hydraulic admittance and transmittance of 20 percent porosity pressed calcite have been investigated experimentally with sine <span class="hlt">wave</span> excitations at pulsations omega between 2 x 10 exp -4 and 0.42 rad/s. Both the modulus and the phase of the complex admittance A(omega) display normal diffusive variations as omega increases. Increasing the viscosity reduces the frequency above which the diffusive behavior is observed. The measured diffusion coefficient is 25 percent higher than that computed from permeability and compressibility values measured independently; this difference may be associated with nonconnected porosity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4011902','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4011902"><span>The 24-hour pulse <span class="hlt">wave</span> velocity, aortic augmentation index, and central blood <span class="hlt">pressure</span> in normotensive volunteers</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kuznetsova, Tatyana Y; Korneva, Viktoria A; Bryantseva, Evgeniya N; Barkan, Vitaliy S; Orlov, Artemy V; Posokhov, Igor N; Rogoza, Anatoly N</p> <p>2014-01-01</p> <p>The purpose of this study was to examine the pulse <span class="hlt">wave</span> velocity, aortic augmentation index corrected for heart rate 75 (AIx@75), and central systolic and diastolic blood <span class="hlt">pressure</span> during 24-hour monitoring in normotensive volunteers. Overall, 467 subjects (206 men and 261 women) were recruited in this study. Participants were excluded from the study if they were less than 19 years of age, had blood test abnormalities, had a body mass index greater than 2 7.5 kg/m2, had impaired glucose tolerance, or had hypotension or hypertension. Ambulatory blood <span class="hlt">pressure</span> monitoring (ABPM) with the BPLab® device was performed in each subject. ABPM waveforms were analyzed using the special automatic Vasotens® algorithm, which allows the calculation of pulse <span class="hlt">wave</span> velocity, AIx@75, central systolic and diastolic blood <span class="hlt">pressure</span> for “24-hour”, “awake”, and “asleep” periods. Circadian rhythms and sex differences in these indexes were identified. Pending further validation in prospective outcome-based studies, our data may be used as preliminary diagnostic values for the BPLab ABPM additional index in adult subjects. PMID:24812515</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24812515','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24812515"><span>The 24-hour pulse <span class="hlt">wave</span> velocity, aortic augmentation index, and central blood <span class="hlt">pressure</span> in normotensive volunteers.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kuznetsova, Tatyana Y; Korneva, Viktoria A; Bryantseva, Evgeniya N; Barkan, Vitaliy S; Orlov, Artemy V; Posokhov, Igor N; Rogoza, Anatoly N</p> <p>2014-01-01</p> <p>The purpose of this study was to examine the pulse <span class="hlt">wave</span> velocity, aortic augmentation index corrected for heart rate 75 (AIx@75), and central systolic and diastolic blood <span class="hlt">pressure</span> during 24-hour monitoring in normotensive volunteers. Overall, 467 subjects (206 men and 261 women) were recruited in this study. Participants were excluded from the study if they were less than 19 years of age, had blood test abnormalities, had a body mass index greater than 2 7.5 kg/m(2), had impaired glucose tolerance, or had hypotension or hypertension. Ambulatory blood <span class="hlt">pressure</span> monitoring (ABPM) with the BPLab(®) device was performed in each subject. ABPM waveforms were analyzed using the special automatic Vasotens(®) algorithm, which allows the calculation of pulse <span class="hlt">wave</span> velocity, AIx@75, central systolic and diastolic blood <span class="hlt">pressure</span> for "24-hour", "awake", and "asleep" periods. Circadian rhythms and sex differences in these indexes were identified. Pending further validation in prospective outcome-based studies, our data may be used as preliminary diagnostic values for the BPLab ABPM additional index in adult subjects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6545919','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6545919"><span>An experimental and theoretical study of density <span class="hlt">wave</span> and <span class="hlt">pressure</span> drop oscillations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yuncu, H. )</p> <p>1990-01-01</p> <p>A study of the stability of an electrically heated, forced-convection, single horizontal channel system with a gas-loaded surge tank placed upstream of the heated channel was conducted. Freon 11 was used as the test fluid. The major modes of oscillations, namely, density <span class="hlt">wave</span>-type (high-frequency) and <span class="hlt">pressure</span> drop-type (low-frequency)oscillations, have been observed. Steady-state <span class="hlt">pressure</span> drops, stable and unstable boundaries are experimentally determined for given ranges of heat flux, mass flow rate, and compressible volume in the surge tank. An analytical model has been developed to predict stable and unstable boundaries for the <span class="hlt">pressure</span> drop and density <span class="hlt">wave</span> oscillations of the boiling two-phase flow system. The model is based on homogenous flow assumption and thermodynamic equilibrium between the liquid and vapor phases. The governing equations are solved first to establish the steady-state behavior of the system. This solution is then used to obtain the unsteady solution by perturbation technique.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121.5587T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121.5587T"><span>Horizontal variability of high-frequency nonlinear internal <span class="hlt">waves</span> in Massachusetts Bay detected by an array of seafloor <span class="hlt">pressure</span> sensors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thomas, J. A.; Lerczak, J. A.; Moum, J. N.</p> <p>2016-08-01</p> <p>A two-dimensional array of 14 seafloor <span class="hlt">pressure</span> sensors was deployed to measure properties of tidally generated, nonlinear, high-frequency internal <span class="hlt">waves</span> over a 14 km by 12 km area west of Stellwagen Bank in Massachusetts Bay during summer 2009. Thirteen high-frequency internal <span class="hlt">wave</span> packets propagated through the region over 6.5 days (one packet every semidiurnal cycle). Propagation speed and direction of <span class="hlt">wave</span> packets were determined by triangulation, using arrival times and distances between triads of sensor locations. Wavefront curvature ranged from straight to radially spreading, with <span class="hlt">wave</span> speeds generally faster to the south. <span class="hlt">Waves</span> propagated to the southwest, rotating to more westward with shoreward propagation. Linear theory predicts a relationship between kinetic energy and bottom <span class="hlt">pressure</span> variance of internal <span class="hlt">waves</span> that is sensitive to sheared background currents, water depth, and stratification. By comparison to seafloor acoustic Doppler current profiler measurements, observations nonetheless show a strong relationship between kinetic energy and bottom <span class="hlt">pressure</span> variance. This is presumably due to phase-locking of the <span class="hlt">wave</span> packets to the internal tide that dominates background currents and to horizontally uniform and relatively constant stratification throughout the study. This relationship was used to qualitatively describe variations in kinetic energy of the high-frequency <span class="hlt">wave</span> packets. In general, high-frequency internal <span class="hlt">wave</span> kinetic energy was greater near the southern extent of wavefronts and greatly decreased upon propagating shoreward of the 40 m isobath.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27369159','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27369159"><span>Analytical analysis of slow and fast <span class="hlt">pressure</span> <span class="hlt">waves</span> in a two-dimensional cellular solid with fluid-filled cells.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dorodnitsyn, Vladimir; Van Damme, Bart</p> <p>2016-06-01</p> <p><span class="hlt">Wave</span> propagation in cellular and porous media is widely studied due to its abundance in nature and industrial applications. Biot's theory for open-cell media predicts the existence of two simultaneous <span class="hlt">pressure</span> <span class="hlt">waves</span>, distinguished by its velocity. A fast <span class="hlt">wave</span> travels through the solid matrix, whereas a much slower <span class="hlt">wave</span> is carried by fluid channels. In closed-cell materials, the slow <span class="hlt">wave</span> disappears due to a lack of a continuous fluid path. However, recent finite element (FE) simulations done by the authors of this paper also predict the presence of slow <span class="hlt">pressure</span> <span class="hlt">waves</span> in saturated closed-cell materials. The nature of the slow <span class="hlt">wave</span> is not clear. In this paper, an equivalent unit cell of a medium with square cells is proposed to permit an analytical description of the dynamics of such a material. A simplified FE model suggests that the fluid-structure interaction can be fully captured using a wavenumber-dependent spring support of the vibrating cell walls. Using this approach, the <span class="hlt">pressure</span> <span class="hlt">wave</span> behavior can be calculated with high accuracy, but with less numerical effort. Finally, Rayleigh's energy method is used to investigate the coexistence of two <span class="hlt">waves</span> with different velocities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JFST....5..235A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JFST....5..235A"><span><span class="hlt">Pressure</span> Generation from Micro-Bubble Collapse at Shock <span class="hlt">Wave</span> Loading</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abe, Akihisa; Ohtani, Kiyonobu; Takayama, Kazuyoshi; Nishio, Shigeru; Mimura, Haruo; Takeda, Minoru</p> <p></p> <p>This paper reports the result of a primary experimental and analytical study used to explore a reliable technology that is potentially applicable to the inactivation of micro-creatures contained in ship ballast water. A shock <span class="hlt">wave</span> generated by the micro-explosion of a 10mg silver azide pellet in a 10mm wide parallel test section was used to interact with a bubble cloud consisting of bubbles with average diameter 10µm produced by a swirling flow type micro-bubble generator. Observations were carried out with a high-speed camera, IMACON200, and the corresponding rebound <span class="hlt">pressures</span> of the collapsing bubbles were measured with a fiber optic probe <span class="hlt">pressure</span> transducer that provides high spatial and temporal resolutions. We found that micro-bubbles collapse in several hundred nanoseconds after the shock exposure and the resulting peak <span class="hlt">pressure</span> pulses that repeatedly occurred exceeded well over 200MPa measured at the 20mm distance from the explosion center. These continued for well over 20µs. The experimental <span class="hlt">pressure</span> responses were explained by solving the one-dimensional bubble Rayleigh-Plesset equation. Such high peak <span class="hlt">pressures</span> could be used effectively for the inactivation of micro-creatures contained in ship ballast water.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110022626','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110022626"><span>A Study of Standing <span class="hlt">Pressure</span> <span class="hlt">Waves</span> Within Open and Closed Acoustic Resonators</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Daniels, C.; Steinetz, B.; Finkbeiner, J.; Raman, G.; Li, X.</p> <p>2002-01-01</p> <p>The first section of the results presented herein was conducted on an axisymmetric resonator configured with open ventilation ports on either end of the resonator, but otherwise closed and free from obstruction. The remaining section presents the results of a similar resonator shape that was closed, but contained an axisymmetric blockage centrally located through the axis of the resonator. Ambient air was used as the working fluid. In each of the studies, the resonator was oscillated at the resonant frequency of the fluid contained within the cavity while the dynamic <span class="hlt">pressure</span>, static <span class="hlt">pressure</span>, and temperature of the fluid were recorded at both ends of the resonator. The baseline results showed a marked reduction in the amplitude of the dynamic <span class="hlt">pressure</span> waveforms over previous studies due to the use of air instead of refrigerant as the working fluid. A sharp reduction in the amplitude of the acoustic <span class="hlt">pressure</span> <span class="hlt">waves</span> was expected and recorded when the configuration of the resonators was modified from closed to open. A change in the resonant frequency was recorded when blockages of differing geometries were used in the closed resonator, while acoustic <span class="hlt">pressure</span> amplitudes varied little from baseline measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010APS..DFD.MJ002B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010APS..DFD.MJ002B"><span>Droplet actuation by surface acoustic <span class="hlt">waves</span>: an interplay between acoustic streaming and radiation <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brunet, Philippe; Baudoin, Michael; Matar, Olivier Bou; Zoueshtiagh, Farzam</p> <p>2010-11-01</p> <p>Surface acoustic <span class="hlt">waves</span> (SAW) are known to be a versatile technique for the actuation of sessile drops. Droplet displacement, internal mixing or drop splitting, are amongst the elementary operations that SAW can achieve, which are useful on lab-on-chip microfluidics benches. On the purpose to understand the underlying physical mechanisms involved during these operations, we study experimentally the droplet dynamics varying different physical parameters. Here in particular, the influence of liquid viscosity and acoustic frequency is investigated: it is indeed predicted that both quantities should play a role in the acoustic-hydrodynamic coupling involved in the dynamics. The key point is to compare the relative magnitude of the attenuation length, i.e. the scale within which the acoustic <span class="hlt">wave</span> decays in the fluid, and the size of the drop. This relative magnitude governs the relative importance of acoustic streaming and acoustic radiation <span class="hlt">pressure</span>, which are both involved in the droplet dynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ShWav..25..415G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ShWav..25..415G"><span>Laser-<span class="hlt">induced</span> blast <span class="hlt">waves</span> in air and their effect on monodisperse droplet chains of ethanol and kerosene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gebel, G. C.; Mosbach, T.; Meier, W.; Aigner, M.</p> <p>2015-07-01</p> <p>Weak spherical blast <span class="hlt">waves</span> in static air and their breakup of ethanol and Jet A-1 kerosene droplets were investigated. The blast <span class="hlt">waves</span> were created by laser-<span class="hlt">induced</span> air breakdowns at ambient temperature and <span class="hlt">pressure</span>. In the first part of this study, they were visualized with schlieren imaging, and their trajectories were tracked with high temporal resolution. The laser pulse energy was varied to create blast <span class="hlt">waves</span> of different strengths. Their initial energies were determined by the application of a numerical and a semi-empirical blast <span class="hlt">wave</span> model. In the second part, monodisperse ethanol and kerosene droplet chains were injected. Their interaction with the blast <span class="hlt">waves</span> was visualized by the application of shadowgraph imaging. The perpendicular distance of the breakdown origin toward the droplet chains was varied to study the effect on the fuel droplets as a function of the distance. Droplets within a few millimeters around the breakdown origin were disintegrated into two to three secondary droplets. The blast-<span class="hlt">induced</span> flow velocities on the post-shock side and the corresponding Weber numbers were calculated from the data of a non-dimensional numerical simulation, and a close look was taken at the breakup process of the droplets. The analysis showed that the aerodynamic force of the blast-<span class="hlt">induced</span> flow was sufficient to deform the droplets into disk-like shapes, but diminished too fast to accomplish breakup. Due to the release of strain energy, the deformed droplets relaxed, stretched into filaments and finally disintegrated by capillary pinching.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22505642','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22505642"><span>Cyclooxygenase inhibition augments central blood <span class="hlt">pressure</span> and aortic <span class="hlt">wave</span> reflection in aging humans.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Barnes, Jill N; Casey, Darren P; Hines, Casey N; Nicholson, Wayne T; Joyner, Michael J</p> <p>2012-06-15</p> <p>The augmentation index and central blood <span class="hlt">pressure</span> increase with normal aging. Recently, cyclooxygenase (COX) inhibitors, commonly used for the treatment of pain, have been associated with transient increases in the risk of cardiovascular events. We examined the effects of the COX inhibitor indomethacin (Indo) on central arterial hemodynamics and <span class="hlt">wave</span> reflection characteristics in young and old healthy adults. High-fidelity radial arterial <span class="hlt">pressure</span> waveforms were measured noninvasively by applanation tonometry before (control) and after Indo treatment in young (25 ± 5 yr, 7 men and 6 women) and old (64 ± 6 yr, 5 men and 6 women) subjects. Aortic systolic (control: 115 ± 3 mmHg vs. Indo: 125 ± 5 mmHg, P < 0.05) and diastolic (control: 74 ± 2 mmHg vs. Indo: 79 ± 3 mmHg, P < 0.05) <span class="hlt">pressures</span> were elevated after Indo treatment in older subjects, whereas only diastolic <span class="hlt">pressure</span> was elevated in young subjects (control: 71 ± 2 mmHg vs. Indo: 76 ± 1 mmHg, P < 0.05). Mean arterial <span class="hlt">pressure</span> increased in both young and old adults after Indo treatment (P < 0.05). The aortic augmentation index and augmented <span class="hlt">pressure</span> were elevated after Indo treatment in older subjects (control: 30 ± 5% vs. Indo 36 ± 6% and control 12 ± 1 mmHg vs. Indo: 18 ± 2 mmHg, respectively, P < 0.05), whereas pulse <span class="hlt">pressure</span> amplification decreased (change: 8 ± 3%, P < 0.05). In addition, older subjects had a 61 ± 11% increase in wasted left ventricular energy after Indo treatment (P < 0.05). In contrast, young subjects showed no significant changes in any of the variables of interest. Taken together, these results demonstrate that COX inhibition with Indo unfavorably increases central <span class="hlt">wave</span> reflection and augments aortic <span class="hlt">pressure</span> in old but not young subjects. Our results suggest that aging individuals have a limited ability to compensate for the acute hemodynamic changes caused by systemic COX inhibition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.9546Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.9546Z"><span>Unusual properties of high-compliance porosity extracted from measurements of <span class="hlt">pressure</span>-dependent <span class="hlt">wave</span> velocities in rocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zaitsev, Vladimir Y.; Radostin, Andrey V.; Pasternak, Elena; Dyskin, Arcady</p> <p>2016-04-01</p> <p>Conventionally the interpretation of <span class="hlt">wave</span> velocities and their variations under load is conducted assuming that closable cracks have simple planar shapes, like the popular model of penny-shape cracks. For such cracks, the proportion between complementary variations in different elastic parameters of rocks (such as S- and P-<span class="hlt">wave</span> velocities) is strictly pre-determined, in particular, it is independent of the crack aspect ratio and rather weakly dependent on the Poisson's ratio of the intact rock. Real rocks, however, contain multitude of cracks of different geometry. Faces of such cracks can exhibit complex modes of interaction when closed by external load, which may result in very different ratios between normal- and shear compliances of such defects. In order to describe the reduction of different elastic moduli, we propose a model in which the compliances of crack-like defects are explicitly decoupled and are not predetermined, so that the ratio q between total normal- and shear- compliances imparted to the rock mass (as well as individual values of these compliances) can be estimated from experimental data on reduction of different elastic moduli (e.g., <span class="hlt">pressure</span> dependences of P- and S-<span class="hlt">wave</span> velocities). Physically, the so-extracted ratio q can be interpreted as intrinsic property of individual crack-like defects similar to each other, or as a characteristic of proportion between concentrations of pure normal cracks with very large q and pure shear cracks with q→0. The latter case can correspond, e.g., to saturated cracks in which weakly-compressible liquid prevents crack closing under normal loading. It can be shown that for conventional dry planar cracks, the compliance ratio is q ˜2. The developed model applied to the data on <span class="hlt">wave</span>-velocity variations with external <span class="hlt">pressure</span> indicates that elastic properties of the real crack-like defects in rocks can differ considerably from the usually assumed ones. Comparison with experimental data on variations P- and S-<span class="hlt">wave</span></p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000JPCM...12.4417S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000JPCM...12.4417S"><span><span class="hlt">Pressure-induced</span> amorphization and orientational disorder in potash alum</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sakuntala, T.; Arora, Akhilesh K.; Shekar, N. V. Chandra; Sahu, P. Ch</p> <p>2000-05-01</p> <p><span class="hlt">Pressure-induced</span> amorphization in potassium aluminium sulphate dodecahydrate (potash alum) has been studied using Raman spectroscopy in a diamond anvil cell up to a <span class="hlt">pressure</span> of 15 GPa. In potash alum, some of the sulphate ions are misoriented with their S-O bond pointing towards potassium rather than aluminium, leading to an `orientational disorder' which ranges from 10 to 24% at ambient conditions. The disorder is quantified from the intensities of the Raman lines characteristic of the two orientations. The samples with low initial disorder exhibit a sequence of two structural phase transitions occurring at 1.5 and 9 GPa respectively. The phase above 1.5 GPa, which could be <span class="hlt">pressure</span> quenched to ambient conditions, is found to be free from orientational disorder. On the other hand, in the samples with high initial disorder, the disorder is found to grow as a function of <span class="hlt">pressure</span> and beyond a critical value the system turns amorphous, which is confirmed from the disappearance of sharp diffraction peaks. In view of these results it is apparent that the orientational disorder is the driving mechanism of amorphization in potash alum. The different initial disorders in different samples are believed to arise from a combination of a dynamic disorder (equilibrium) and a static disorder arising from the defects. This defect could possibly be a missing molecule in the water octahedra around the potassium ion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004PSSBR.241.3179V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004PSSBR.241.3179V"><span>Structural phase transition in lanthanum monochalcogenides <span class="hlt">induced</span> by hydrostatic <span class="hlt">pressure</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Varshney, Dinesh; Kaurav, N.; Sharma, P.; Shah, S.; Singh, R. K.</p> <p>2004-11-01</p> <p>An effective interionic interaction potential (EIOP) is developed to investigate the <span class="hlt">pressure</span> <span class="hlt">induced</span> phase transitions from NaCl-type (B1) to CsCl-type (B2) structure in lanthanum monochalcogenides LaX [X = S, Se, Te] compounds. The long range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction up to second-neighbor ions within the Hafemeister and Flygare approach with modified ionic charge are properly incorporated in EIOP. The vdW coefficients are computed following the Slater-Kirkwood variational method, as both the ions are polarizable. The estimated value of the phase transition <span class="hlt">pressure</span> (Pt) and the magnitude of the discontinuity in volume at the transition <span class="hlt">pressure</span> are consistent with the reported data. A large volume discontinuity in the <span class="hlt">pressure</span>-volume phase diagram identifies the structural phase transition from B1 to B2 structure. We also study the second order elastic constants for these La compounds. It appears that the vdW interaction is effective in determining the elastic and structural properties of these test compounds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4765376','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4765376"><span>Ultrasound Shear <span class="hlt">Wave</span> Elasticity Imaging Quantifies Coronary Perfusion <span class="hlt">Pressure</span> Effect on Cardiac Compliance</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Nagle, Matt; Trahey, Gregg E.; Wolf, Patrick D.</p> <p>2016-01-01</p> <p>Diastolic heart failure (DHF) is a major source of cardiac related morbidity and mortality in the world today. A major contributor to, or indicator of DHF is a change in cardiac compliance. Currently, there is no accepted clinical method to evaluate the compliance of cardiac tissue in diastolic dysfunction. Shear <span class="hlt">wave</span> elasticity imaging (SWEI) is a novel ultrasound-based elastography technique that provides a measure of tissue stiffness. Coronary perfusion <span class="hlt">pressure</span> affects cardiac stiffness during diastole; we sought to characterize the relationship between these two parameters using the SWEI technique. In this work, we demonstrate how changes in coronary perfusion <span class="hlt">pressure</span> are reflected in a local SWEI measurement of stiffness during diastole. Eight Langendorff perfused isolated rabbit hearts were used in this study. Coronary perfusion <span class="hlt">pressure</span> was changed in a randomized order (0–90 mmHg range) and SWEI measurements were recorded during diastole with each change. Coronary perfusion <span class="hlt">pressure</span> and the SWEI measurement of stiffness had a positive linear correlation with the 95% confidence interval (CI) for the slope of 0.009–0.011 m/s/mmHg (R2 = 0.88). Furthermore, shear modulus was linearly correlated to the coronary perfusion <span class="hlt">pressure</span> with the 95% CI of this slope of 0.035–0.042 kPa/mmHg (R2 = 0.83). In conclusion, diastolic SWEI measurements of stiffness can be used to characterize factors affecting cardiac compliance specifically the mechanical interaction (cross-talk) between perfusion <span class="hlt">pressure</span> in the coronary vasculature and cardiac muscle. This relationship was found to be linear over the range of <span class="hlt">pressures</span> tested. PMID:25291788</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.3694M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.3694M"><span>Temporal pore <span class="hlt">pressure</span> <span class="hlt">induced</span> stress changes during injection and depletion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Müller, Birgit; Heidbach, Oliver; Schilling, Frank; Fuchs, Karl; Röckel, Thomas</p> <p>2016-04-01</p> <p><span class="hlt">Induced</span> seismicity is observed during injection of fluids in oil, gas or geothermal wells as a rather immediate response close to the injection wells due to the often high-rate <span class="hlt">pressurization</span>. It was recognized even earlier in connection with more moderate rate injection of fluid waste on a longer time frame but higher <span class="hlt">induced</span> event magnitudes. Today, injection-related <span class="hlt">induced</span> seismicity significantly increased the number of events with M>3 in the Mid U.S. However, <span class="hlt">induced</span> seismicity is also observed during production of fluids and gas, even years after the onset of production. E.g. in the Groningen gas field production was required to be reduced due to the increase in felt and damaging seismicity after more than 50 years of exploitation of that field. Thus, injection and production <span class="hlt">induced</span> seismicity can cause severe impact in terms of hazard but also on economic measures. In order to understand the different onset times of <span class="hlt">induced</span> seismicity we built a generic model to quantify the role of poro-elasticity processes with special emphasis on the factors time, regional crustal stress conditions and fault parameters for three case studies (injection into a low permeable crystalline rock, hydrothermal circulation and production of fluids). With this approach we consider the spatial and temporal variation of reservoir stress paths, the "early" injection-related <span class="hlt">induced</span> events during stimulation and the "late" production <span class="hlt">induced</span> ones. Furthermore, in dependence of the undisturbed in situ stress field conditions the stress tensor can change significantly due to injection and long-term production with changes of the tectonic stress regime in which previously not critically stressed faults could turn to be optimally oriented for fault reactivation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24997065','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24997065"><span>[P <span class="hlt">wave</span> dispersion increased in childhood depending on blood <span class="hlt">pressure</span>, weight, height, and cardiac structure and function].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chávez-González, Elibet; González-Rodríguez, Emilio; Llanes-Camacho, María Del Carmen; Garí-Llanes, Merlin; García-Nóbrega, Yosvany; García-Sáez, Julieta</p> <p>2014-01-01</p> <p>Increased P <span class="hlt">wave</span> dispersion are identified as a predictor of atrial fibrillation. There are associations between hypertension, P <span class="hlt">wave</span> dispersion, constitutional and echocardiographic variables. These relationships have been scarcely studied in pediatrics. The aim of this study was to determine the relationship between P <span class="hlt">wave</span> dispersion, blood <span class="hlt">pressure</span>, echocardiographic and constitutional variables, and determine the most influential variables on P <span class="hlt">wave</span> dispersion increases in pediatrics. In the frame of the PROCDEC II project, children from 8 to 11 years old, without known heart conditions were studied. Arterial blood <span class="hlt">pressure</span> was measured in all the children; a 12-lead surface electrocardiogram and an echocardiogram were done as well. Left ventricular mass index mean values for normotensive (25.91±5.96g/m(2.7)) and hypertensive (30.34±8.48g/m(2.7)) showed significant differences P=.000. When we add prehypertensive and hypertensive there are 50.38% with normal left ventricular mass index and P <span class="hlt">wave</span> dispersion was increased versus 13.36% of normotensive. Multiple regression demonstrated that the mean blood <span class="hlt">pressure</span>, duration of A <span class="hlt">wave</span> of mitral inflow, weight and height have a value of r=0.88 as related to P <span class="hlt">wave</span> dispersion. P <span class="hlt">wave</span> dispersion is increased in pre- and hypertensive children compared to normotensive. There are pre- and hypertensive patients with normal left ventricular mass index and increased P <span class="hlt">wave</span> dispersion. Mean arterial <span class="hlt">pressure</span>, duration of the A <span class="hlt">wave</span> of mitral inflow, weight and height are the variables with the highest influence on increased P <span class="hlt">wave</span> dispersion. Copyright © 2013 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS23B2050T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS23B2050T"><span>Surface-<span class="hlt">wave-induced</span> sub- and super-harmonic internal <span class="hlt">waves</span> over lutocline</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tahvildari, N.</p> <p>2016-12-01</p> <p>Previous experimental and theoretical works have shown that a monochromatic surface <span class="hlt">wave</span> can generate a pair of subharmonic oblique internal <span class="hlt">waves</span> in a two-layer fluid through nonlinear interactions. Recent experiments on <span class="hlt">wave</span>-mud interaction have observed additional higher internal <span class="hlt">wave</span> harmonics over water-mud interface, or lutocline. In this study, we develop an analytical and analytical-numerical models to examine two mechanisms through which a surface <span class="hlt">wave</span> can generate superharmonic internal <span class="hlt">waves</span>. The water-fluid mud system is assumed to behave as a two-layer fluid with homogenous, incompressible, and immiscible fluid layers. Surface and internal <span class="hlt">waves</span> are assumed to be in intermediate depth, and both layers are assumed to be lightly viscous. The first mechanism involves a primary surface <span class="hlt">wave</span> harmonic that generates two oblique internal <span class="hlt">waves</span>. Through self-interaction, the primary surface <span class="hlt">wave</span> generates a second harmonic which in turn can generate two internal <span class="hlt">waves</span>. These subharmonic internal <span class="hlt">waves</span> have the same frequency as the primary surface <span class="hlt">wave</span> and appear to be superhamonic to the internal <span class="hlt">waves</span> it generates. The second generation mechanism is the self-interaction of the internal <span class="hlt">waves</span> generated by the primary surface <span class="hlt">wave</span>. We compare the growth rate of the internal <span class="hlt">wave</span> superharmonics that are generated through these two mechanisms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18835205','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18835205"><span>Continuous-<span class="hlt">wave</span> far-infrared ESR spectrometer for high-<span class="hlt">pressure</span> measurements.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Náfrádi, Bálint; Gaál, Richárd; Sienkiewicz, Andrzej; Fehér, Titusz; Forró, László</p> <p>2008-12-01</p> <p>We present a newly-developed microwave probe for performing sensitive high-field/multi-frequency electron spin resonance (ESR) measurements under high hydrostatic <span class="hlt">pressures</span>. The system consists of a BeCu-made <span class="hlt">pressure</span>-resistant vessel, which accommodates the investigated sample and a diamond microwave coupling window. The probe's interior is completely filled with a <span class="hlt">pressure</span>-transmitting fluid. The setup operates in reflection mode and can easily be assembled with a standard oversized microwave circuitry. The probe-head withstands hydrostatic <span class="hlt">pressures</span> up to 1.6 GPa and interfaces with our home-built quasi-optical high-field ESR facility, operating in a millimeter/submillimeter frequency range of 105-420 GHz and in magnetic fields up to 16 T. The overall performance of the probe was tested, while studying the <span class="hlt">pressure-induced</span> changes in the spin-relaxation mechanisms of a quasi-1D conducting polymer, KC(60). The preliminary measurements revealed that the probe yields similar signal-to-noise ratio to that of commercially available low-frequency ESR spectrometers. Moreo