Phantom behavior bounce with tachyon and non-minimal derivative coupling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Banijamali, A.; Fazlpour, B., E-mail: a.banijamali@nit.ac.ir, E-mail: b.fazlpour@umz.ac.ir

2012-01-01

The bouncing cosmology provides a successful solution of the cosmological singularity problem. In this paper, we study the bouncing behavior of a single scalar field model with tachyon field non-minimally coupled to itself, its derivative and to the curvature. By utilizing the numerical calculations we will show that the bouncing solution can appear in the universe dominated by such a quintom matter with equation of state crossing the phantom divide line. We also investigate the classical stability of our model using the phase velocity of the homogeneous perturbations of the tachyon scalar field.

Behaviour of a Bouncing Ball

ERIC Educational Resources Information Center

Cross, Rod

2015-01-01

The bounce of a ball is a seemingly innocuous event that can be used to illustrate many aspects of elementary and even advanced mechanics. Both normal and oblique bounces on a rigid surface are considered in this article, emphasizing qualitative features of the bounce process. If the ball bounces at an oblique angle then it can slide throughout…

Consistent scalar and tensor perturbation power spectra in single fluid matter bounce with dark energy era

NASA Astrophysics Data System (ADS)

Bacalhau, Anna Paula; Pinto-Neto, Nelson; Vitenti, Sandro Dias Pinto

2018-04-01

We investigate cosmological scenarios containing one canonical scalar field with an exponential potential in the context of bouncing models, in which the bounce happens due to quantum cosmological effects. The only possible bouncing solutions in this scenario (discarding an infinitely fine-tuned exception) must have one and only one dark energy phase, occurring either in the contracting era or in the expanding era. Hence, these bounce solutions are necessarily asymmetric. Naturally, the more convenient solution is the one in which the dark energy phase happens in the expanding era, in order to be a possible explanation for the current accelerated expansion indicated by cosmological observations. In this case, one has the picture of a Universe undergoing a classical dust contraction from very large scales, the initial repeller of the model, moving to a classical stiff-matter contraction near the singularity, which is avoided due to the quantum bounce. The Universe is then launched to a dark energy era, after passing through radiation- and dust-dominated phases, finally returning to the dust expanding phase, the final attractor of the model. We calculate the spectral indices and amplitudes of scalar and tensor perturbations numerically, considering the whole history of the model, including the bounce phase itself, without making any approximation nor using any matching condition on the perturbations. As the background model is necessarily dust dominated in the far past, the usual adiabatic vacuum initial conditions can be easily imposed in this era. Hence, this is a cosmological model in which the presence of dark energy behavior in the Universe does not turn the usual vacuum initial conditions prescription for cosmological perturbation in bouncing models problematic. Scalar and tensor perturbations end up being almost scale invariant, as expected. The background parameters can be adjusted, without fine-tunings, to yield the observed amplitude for scalar

'Bounce': Not Like the Others

NASA Technical Reports Server (NTRS)

2004-01-01

This illustration shows that the rock dubbed 'Bounce' near the Mars Exploration Rover Opportunity's landing region at Meridiani Planum is not made up of the same minerals as surrounding soil. Spectra from three soil samples taken outside of 'Eagle Crater' are compared to that of Bounce (bottom). The dashed white line in the center of the spectra indicates where the 'fingerprint' for triple-oxidized iron (Fe 3+) occurs. While the soil samples possess this feature, Bounce does not. The results suggest that Bounce did not originate in the plains of Meridiani Planum. These spectra were taken by the rover's Moessbauer spectrometer. Measurements of Bounce were made on sol 67.

Nonlinear bounce resonances between magnetosonic waves and equatorially mirroring electrons

NASA Astrophysics Data System (ADS)

Chen, Lunjin; Maldonado, Armando; Bortnik, Jacob; Thorne, Richard M.; Li, Jinxing; Dai, Lei; Zhan, Xiaoya

2015-08-01

Equatorially mirroring energetic electrons pose an interesting scientific problem, since they generally cannot resonate with any known plasma waves and hence cannot be scattered down to lower pitch angles. Observationally it is well known that the flux of these equatorial particles does not simply continue to build up indefinitely, and so a mechanism must necessarily exist that transports these particles from an equatorial pitch angle of 90° down to lower values. However, this mechanism has not been uniquely identified yet. Here we investigate the mechanism of bounce resonance with equatorial noise (or fast magnetosonic waves). A test particle simulation is used to examine the effects of monochromatic magnetosonic waves on the equatorially mirroring energetic electrons, with a special interest in characterizing the effectiveness of bounce resonances. Our analysis shows that bounce resonances can occur at the first three harmonics of the bounce frequency (nωb, n = 1, 2, and 3) and can effectively reduce the equatorial pitch angle to values where resonant scattering by whistler mode waves becomes possible. We demonstrate that the nature of bounce resonance is nonlinear, and we propose a nonlinear oscillation model for characterizing bounce resonances using two key parameters, effective wave amplitude à and normalized wave number k~z. The threshold for higher harmonic resonance is more strict, favoring higher à and k~z, and the change in equatorial pitch angle is strongly controlled by k~z. We also investigate the dependence of bounce resonance effects on various physical parameters, including wave amplitude, frequency, wave normal angle and initial phase, plasma density, and electron energy. It is found that the effect of bounce resonance is sensitive to the wave normal angle. We suggest that the bounce resonant interaction might lead to an observed pitch angle distribution with a minimum at 90°.

Fully stable cosmological solutions with a non-singular classical bounce

DOE PAGES

Ijjas, Anna; Steinhardt, Paul J.

2016-11-28

Recently, we showed how it is possible to use a cubic Galileon action to construct classical cosmological solutions that enter a contracting null energy condition (NEC) violating phase, bounce at finite values of the scale factor and exit into an expanding NEC-satisfying phase without encountering any singularities or pathologies. One drawback of these examples is that singular behavior is encountered at some time either just before or just after the NEC-violating phase. In this Letter, we show that it is possible to circumvent this problem by extending our method to actions that include the next order L 4 Galileon interaction.more » In using this approach, we construct non-singular classical bouncing cosmological solutions that are non-pathological for all times.« less

Eye on 'Bounce'

NASA Technical Reports Server (NTRS)

2004-01-01

This mosaic, created from four images taken by the Mars Exploration Rover Opportunity's microscopic imager, outlines the target on 'Bounce' rock that the rover's rock abrasion tool will abrade on sol 66.

This 6-centimeter-square (2.4-inch-square) area was chosen by the rock abrasion tool team as the most advantageous area for grinding.

Preliminary results from the rover's miniature thermal emission spectrometer show that Bounce is rich in hematite. Bounce contains spherules, or 'blueberries,' like some rocks in the 'Eagle Crater' outcrop. However, Bounce's spherules appear smaller and may be formed by an entirely different process. The blueberries seen in the outcrop are typically 3 to 4 millimeters (0.12 to 0.16 inch) each. A good example of a cluster of micro-berries can be seen just left of center in this image. Scientists are currently studying all of the rock's features as well as its chemical content. After next sol's grinding operation, the team will be able to compare the rock's exterior and interior chemical compositions.

Bouncing cosmological solutions from f(R,T) gravity

NASA Astrophysics Data System (ADS)

Shabani, Hamid; Ziaie, Amir Hadi

2018-05-01

In this work we study classical bouncing solutions in the context of f(R,T)=R+h(T) gravity in a flat FLRW background using a perfect fluid as the only matter content. Our investigation is based on introducing an effective fluid through defining effective energy density and pressure; we call this reformulation as the " effective picture". These definitions have been already introduced to study the energy conditions in f(R,T) gravity. We examine various models to which different effective equations of state, corresponding to different h(T) functions, can be attributed. It is also discussed that one can link between an assumed f(R,T) model in the effective picture and the theories with generalized equation of state ( EoS). We obtain cosmological scenarios exhibiting a nonsingular bounce before and after which the Universe lives within a de-Sitter phase. We then proceed to find general solutions for matter bounce and investigate their properties. We show that the properties of bouncing solution in the effective picture of f(R,T) gravity are as follows: for a specific form of the f(R,T) function, these solutions are without any future singularities. Moreover, stability analysis of the nonsingular solutions through matter density perturbations revealed that except two of the models, the parameters of scalar-type perturbations for the other ones have a slight transient fluctuation around the bounce point and damp to zero or a finite value at late times. Hence these bouncing solutions are stable against scalar-type perturbations. It is possible that all energy conditions be respected by the real perfect fluid, however, the null and the strong energy conditions can be violated by the effective fluid near the bounce event. These solutions always correspond to a maximum in the real matter energy density and a vanishing minimum in the effective density. The effective pressure varies between negative values and may show either a minimum or a maximum.

Phase III Early Restoration Public Meetings | NOAA Gulf Spill Restoration

Science.gov Websites

Archive Home Phase III Early Restoration Public Meetings Phase III Early Restoration Public Meetings share Posted on December 6, 2013 | Assessment and Early Restoration Restoration Area Title: Phase III Early on the draft plan for the third phase of Early Restoration, which proposes more than $625 million in

Field validation of Tasmania's aquaculture industry bounce-diving schedules using Doppler analysis of decompression stress.

PubMed

Smart, David R; Van den Broek, Cory; Nishi, Ron; Cooper, P David; Eastman, David

2014-09-01

Tasmania's aquaculture industry produces over 40,000 tonnes of fish annually, valued at over AUD500M. Aquaculture divers perform repetitive, short-duration bounce dives in fish pens to depths up to 21 metres' sea water (msw). Past high levels of decompression illness (DCI) may have resulted from these 'yo-yo' dives. This study aimed to assess working divers, using Doppler ultrasonic bubble detection, to determine if yo-yo diving was a risk factor for DCI, determine dive profiles with acceptable risk and investigate productivity improvement. Field data were collected from working divers during bounce diving at marine farms near Hobart, Australia. Ascent rates were less than 18 m·min⁻¹, with routine safety stops (3 min at 3 msw) during the final ascent. The Kisman-Masurel method was used to grade bubbling post dive as a means of assessing decompression stress. In accordance with Defence Research and Development Canada Toronto practice, dives were rejected as excessive risk if more than 50% of scores were over Grade 2. From 2002 to 2008, Doppler data were collected from 150 bounce-dive series (55 divers, 1,110 bounces). Three series of bounce profiles, characterized by in-water times, were validated: 13-15 msw, 10 bounces inside 75 min; 16-18 msw, six bounces inside 50 min; and 19-21 msw, four bounces inside 35 min. All had median bubble grades of 0. Further evaluation validated two successive series of bounces. Bubble grades were consistent with low-stress dive profiles. Bubble grades did not correlate with the number of bounces, but did correlate with ascent rate and in-water time. These data suggest bounce diving was not a major factor causing DCI in Tasmanian aquaculture divers. Analysis of field data has improved industry productivity by increasing the permissible number of bounces, compared to earlier empirically-derived tables, without compromising safety. The recommended Tasmanian Bounce Diving Tables provide guidance for bounce diving to a depth of 21 msw

Primordial magnetic fields from a non-singular bouncing cosmology

NASA Astrophysics Data System (ADS)

Membiela, Federico Agustín

2014-08-01

Although inflation is a natural candidate to generate the lengths of coherence of magnetic fields needed to explain current observations, it needs to break conformal invariance of electromagnetism to obtain significant magnetic amplitudes. Of the simplest realizations are the kinetically-coupled theories f2(ϕ)FμνF (or IFF theories). However, these are known to suffer from electric fields backreaction or the strong coupling problem. In this work we shall confirm that such class of theories are problematic to support magnetogenesis during inflationary cosmology. On the contrary, we show that a bouncing cosmology with a contracting phase dominated by an equation of state with p>-ρ/3 can support magnetogenesis, evading the backreaction/strong-coupling problem. Finally, we study safe magnetogenesis in a particular bouncing model with an ekpyrotic-like contracting phase. In this case we found that f2(ϕ)F2-instabilities might arise during the final kinetic-driven expanding phase for steep ekpyrotic potentials.

The Blue Straggler Star Population in NGC 1261: Evidence for a Post-core-collapse Bounce State

NASA Astrophysics Data System (ADS)

Simunovic, Mirko; Puzia, Thomas H.; Sills, Alison

2014-11-01

We present a multi-passband photometric study of the Blue Straggler Star (BSS) population in the Galactic globular cluster (GC) NGC 1261, using available space- and ground-based survey data. The inner BSS population is found to have two distinct sequences in the color-magnitude diagram (CMD), similar to double BSS sequences detected in other GCs. These well defined sequences are presumably linked to single short-lived events such as core collapse, which are expected to boost the formation of BSSs. In agreement with this, we find a BSS sequence in NGC 1261 which can be well reproduced individually by a theoretical model prediction of a 2 Gyr old population of stellar collision products, which are expected to form in the denser inner regions during short-lived core contraction phases. Additionally, we report the occurrence of a group of BSSs with unusually blue colors in the CMD, which are consistent with a corresponding model of a 200 Myr old population of stellar collision products. The properties of the NGC 1261 BSS populations, including their spatial distributions, suggest an advanced dynamical evolutionary state of the cluster, but the core of this GC does not show the classical signatures of core collapse. We argue that these apparent contradictions provide evidence for a post-core-collapse bounce state seen in dynamical simulations of old GCs.

Galileon bounce after ekpyrotic contraction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Osipov, M.; Rubakov, V., E-mail: osipov@ms2.inr.ac.ru, E-mail: rubakov@ms2.inr.ac.ru

We consider a simple cosmological model that includes a long ekpyrotic contraction stage and smooth bounce after it. Ekpyrotic behavior is due to a scalar field with a negative exponential potential, whereas the Galileon field produces bounce. We give an analytical picture of how the bounce occurs within the weak gravity regime, and then perform numerical analysis to extend our results to a non-perturbative regime.

Primordial gravitational waves in a quantum model of big bounce

NASA Astrophysics Data System (ADS)

Bergeron, Hervé; Gazeau, Jean Pierre; Małkiewicz, Przemysław

2018-05-01

We quantise and solve the dynamics of gravitational waves in a quantum Friedmann-Lemaitre-Robertson-Walker spacetime filled with perfect fluid. The classical model is formulated canonically. The Hamiltonian constraint is de-parametrised by setting a fluid variable as the internal clock. The obtained reduced (i.e. physical) phase space is then quantised. Our quantisation procedure is implemented in accordance with two different phase space symmetries, namely, the Weyl-Heisenberg symmetry for the perturbation variables, and the affine symmetry for the background variables. As an appealing outcome, the initial singularity is removed and replaced with a quantum bounce. The quantum model depends on a free parameter that is naturally induced from quantisation and determines the scale of the bounce. We study the dynamics of the quantised gravitational waves across the bounce through three different methods ("thin-horizon", analytical and numerical) which give consistent results and we determine the primordial power spectrum for the case of radiation-dominated universe. Next, we use the instantaneous radiation-matter transition transfer function to make approximate predictions for late universe and constrain our model with LIGO and Planck data. We also give an estimate of the quantum uncertainties in the present-day universe.

"Bouncing back": how Australia's leading women's magazines portray the postpartum 'body'.

PubMed

Roth, Heike; Homer, Caroline; Fenwick, Jennifer

2012-09-01

To examine how the Australian media portrays the childbearing body through the use of celebrity stories in women's magazines. The study aimed to provide insight into socially constructed factors that might influence women's body image and expectations during pregnancy and the early postnatal period. Media content analysis was used to analyse 25 celebrity stories about the childbearing postnatal body (images and texts) collected from Australia's three leading women's magazines between January and June 2009 (n=58). A variety of persuasive textual and visual messages were elicited. The major theme representing how the postnatal body was constructed was labelled 'Bouncing back'; the focus of this paper. The social messages inherent in the magazine stories were that women need to strive towards regaining a pre-pregnant body shape with the same effort one would employ when recovering from an illness. Three specific sub-themes that promoted weight loss were identified. These were labelled 'Racing to bounce back', 'Breastfeeding to bounce back' and 'Pretending to bounce back'. A fourth sub-theme, 'Refusing to bounce back: Celebrating my new body', grouped together stories about celebrities who appeared to embrace their changed, but healthy, postnatal body. The study highlighted the expectations of the postpartum body in relation to speedy return to the pre-pregnant state. Understanding how these portrayals may contribute to women's own body image and expectations in the early postpartum period may better assist maternity health care providers to engage with women in meaningful discussions about this important time in their lives and challenge notions of ideal body types. Assisting women to accept and nurture themselves and have confidence in their ability as a new parent is a crucial element of quality maternity service provision. Copyright © 2011 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

'Bounce' and Shergotty Share Common Ground

NASA Technical Reports Server (NTRS)

2004-01-01

This illustration compares the spectrum of 'Bounce,' a rock at Meridiani Planum, to that of a martian meteorite found on Earth called Shergotty. Bounce's spectrum, and thus mineral composition, is unique to the rocks studied so far at Merdiani Planum and Gusev Crater, the landings sites of the Mars Exploration Rovers Opportunity and Spirit. However, the results here indicate that Bounce is not a one-of-a-kind rock, but shares origins with Shergotty. Shergotty landed in India in 1865. Bounce's spectra were taken on sol 67 by Opportunity's Moessbauer spectrometer.

Exploring the Mathematics of Bouncing Balls

ERIC Educational Resources Information Center

Vinogradova, Natalya; Blaine, Larry G.

2010-01-01

A common textbook problem asks students to calculate the total distance traveled by a bouncing ball, from its initial release until it comes to rest, under the assumption that the height of each bounce is some fixed proportion "r" of the height of the previous bounce. The solution is found by inserting information about "r" and the height from…

The matter-ekpyrotic bounce scenario in Loop Quantum Cosmology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haro, Jaume; Amorós, Jaume; Saló, Llibert Aresté, E-mail: jaime.haro@upc.edu, E-mail: jaume.amoros@upc.edu, E-mail: llibert.areste@estudiant.upc.edu

We will perform a detailed study of the matter-ekpyrotic bouncing scenario in Loop Quantum Cosmology using the methods of the dynamical systems theory. We will show that when the background is driven by a single scalar field, at very late times, in the contracting phase, all orbits depict a matter dominated Universe, which evolves to an ekpyrotic phase. After the bounce the Universe enters in the expanding phase, where the orbits leave the ekpyrotic regime going to a kination (also named deflationary) regime. Moreover, this scenario supports the production of heavy massive particles conformally coupled with gravity, which reheats themore » universe at temperatures compatible with the nucleosynthesis bounds and also the production of massless particles non-conformally coupled with gravity leading to very high reheating temperatures but ensuring the nucleosynthesis success. Dealing with cosmological perturbations, these background dynamics produce a nearly scale invariant power spectrum for the modes that leave the Hubble radius, in the contracting phase, when the Universe is quasi-matter dominated, whose spectral index and corresponding running is compatible with the recent experimental data obtained by PLANCK's team.« less

Double Bounce Component in Cross-Polarimetric SAR from a New Scattering Target Decomposition

NASA Astrophysics Data System (ADS)

Hong, Sang-Hoon; Wdowinski, Shimon

2013-08-01

Common vegetation scattering theories assume that the Synthetic Aperture Radar (SAR) cross-polarization (cross-pol) signal represents solely volume scattering. We found this assumption incorrect based on SAR phase measurements acquired over the south Florida Everglades wetlands indicating that the cross-pol radar signal often samples the water surface beneath the vegetation. Based on these new observations, we propose that the cross-pol measurement consists of both volume scattering and double bounce components. The simplest multi-bounce scattering mechanism that generates cross-pol signal occurs by rotated dihedrals. Thus, we use the rotated dihedral mechanism with probability density function to revise some of the vegetation scattering theories and develop a three- component decomposition algorithm with single bounce, double bounce from both co-pol and cross-pol, and volume scattering components. We applied the new decomposition analysis to both urban and rural environments using Radarsat-2 quad-pol datasets. The decomposition of the San Francisco's urban area shows higher double bounce scattering and reduced volume scattering compared to other common three-component decomposition. The decomposition of the rural Everglades area shows that the relations between volume and cross-pol double bounce depend on the vegetation density. The new decomposition can be useful to better understand vegetation scattering behavior over the various surfaces and the estimation of above ground biomass using SAR observations.

Collective many-body bounce in the breathing-mode oscillations of a Tonks-Girardeau gas

NASA Astrophysics Data System (ADS)

Atas, Y. Y.; Bouchoule, I.; Gangardt, D. M.; Kheruntsyan, K. V.

2017-10-01

We analyze the breathing-mode oscillations of a harmonically quenched Tonks-Giradeau (TG) gas using an exact finite-temperature dynamical theory. We predict a striking collective manifestation of impenetrability—a collective many-body bounce effect. The effect, although being invisible in the evolution of the in situ density profile of the gas, can be revealed through a nontrivial periodic narrowing of its momentum distribution, taking place at twice the rate of the fundamental breathing-mode frequency. We identify physical regimes for observing the many-body bounce and construct the respective nonequilibrium phase diagram as a function of the quench strength and the initial temperature of the gas. We also develop a finite-temperature hydrodynamic theory of the TG gas wherein the many-body bounce is explained by an increased thermodynamic pressure during the isentropic compression cycle, which acts as a potential barrier for the particles to bounce off.

Audiovisual Bounce-Inducing Effect: Attention Alone Does Not Explain Why the Discs Are Bouncing

ERIC Educational Resources Information Center

Grassi, Massimo; Casco, Clara

2009-01-01

Two discs moving from opposite points in space, overlapping and stopping at the other disc's starting point, can be seen as either bouncing or streaming through each other. With silent displays, observers report the discs as streaming, whereas if a sound is played when the discs touch each other, observers report the discs as bouncing. The origin…

Detectability of primordial gravitational waves produced in bouncing models

NASA Astrophysics Data System (ADS)

Pinto-Neto, Nelson; Scardua, Arthur

2017-06-01

It is widely known that bouncing models with a dust hydrodynamical fluid satisfying cs2=pd/ρd≈0 , where cs , pd , ρd are the sound velocity, pressure, and energy density of the dust fluid, respectively, have almost scale invariant spectrum of scalar perturbations and negligible primordial gravitational waves. We investigate whether adding another fluid with 1 /3 bounce, can increase the amplitude of gravitational waves in the high frequency regime, turning them detectable in near future observations for such range of frequencies. Indeed, we show that the energy density of primordial gravitational waves is proportional to k2 (9 w -1 )/(1 +3 w ) for wavelengths which become bigger than the Hubble radius when this extra fluid dominates the background. Hence, as w →1 (an almost stiff matter fluid), the energy density of primordial gravitational waves will increase faster in frequency, turning them potentially detectable at high frequencies. However, there is an extra factor Iq(w ) in the amplitude which decreases exponentially with w . The net effect of these two contributions turns the energy density of primordial gravitational waves not sufficiently big at high frequencies in order to be detected by present day or near future observations for models which satisfy the nucleosynthesis bounds and is symmetric with respect to the bounce. Hence, symmetric bouncing models where the background is dominated by a dust hydrodynamical fluid with small sound velocity, do not present any significant amount of primordial gravitational waves at any frequency range compatible with observations, even if there are other fields present in the model dominating the bounce phase. Any detection of such waves will then rule out this kind of model.

Absolute Lower Bound on the Bounce Action

NASA Astrophysics Data System (ADS)

Sato, Ryosuke; Takimoto, Masahiro

2018-03-01

The decay rate of a false vacuum is determined by the minimal action solution of the tunneling field: bounce. In this Letter, we focus on models with scalar fields which have a canonical kinetic term in N (>2 ) dimensional Euclidean space, and derive an absolute lower bound on the bounce action. In the case of four-dimensional space, we show the bounce action is generically larger than 24 /λcr, where λcr≡max [-4 V (ϕ )/|ϕ |4] with the false vacuum being at ϕ =0 and V (0 )=0 . We derive this bound on the bounce action without solving the equation of motion explicitly. Our bound is derived by a quite simple discussion, and it provides useful information even if it is difficult to obtain the explicit form of the bounce solution. Our bound offers a sufficient condition for the stability of a false vacuum, and it is useful as a quick check on the vacuum stability for given models. Our bound can be applied to a broad class of scalar potential with any number of scalar fields. We also discuss a necessary condition for the bounce action taking a value close to this lower bound.

Reflections on a Bouncing Ball

ERIC Educational Resources Information Center

Rohr, Jim; Lopez, Veronica; Rohr, Tyler

2014-01-01

While observing the bounce heights of various kinds of sports balls dropped from different heights onto a variety of surfaces, we thought of the following question: Could measurements of drop and bounce heights of balls of different diameters, but of the same material, falling from different heights, but on the same surface, be expressed by a…

Bouncing cosmology from warped extra dimensional scenario

NASA Astrophysics Data System (ADS)

Das, Ashmita; Maity, Debaprasad; Paul, Tanmoy; SenGupta, Soumitra

2017-12-01

From the perspective of four dimensional effective theory on a two brane warped geometry model, we examine the possibility of "bouncing phenomena"on our visible brane. Our results reveal that the presence of a warped extra dimension lead to a non-singular bounce on the brane scale factor and hence can remove the "big-bang singularity". We also examine the possible parametric regions for which this bouncing is possible.

Multi-bounce laser-based sails

NASA Astrophysics Data System (ADS)

Metzger, Robert A.; Landis, Geoffrey

2001-02-01

A laser-based lightsail craft is proposed in which the laser beam is operated in a multi-bounce mode, such that after first striking the lightsail, the beam is reflected back to a source reflector where it is again directed to the lightsail. Recent developments in nearly ideal reflectors permit more than 1000 bounces, which reduce the laser power requirements by a factor of 1000 as compared to conventional laser-based lightsail proposals. Using the multi-bounce lightsail approach coupled with lasers operating in the power range of 100 MW to 1 GW, the details of a mission to Mars requiring only a sub-100 day transit, and an orbital transfer vehicle designed to transport cargo between Phobos and Deimos are examined. .

Primordial perturbations with pre-inflationary bounce

NASA Astrophysics Data System (ADS)

Cai, Yong; Wang, Yu-Tong; Zhao, Jin-Yun; Piao, Yun-Song

2018-05-01

Based on the effective field theory (EFT) of nonsingular cosmologies, we build a stable model, without the ghost and gradient instabilities, of bounce-inflation (inflation is preceded by a cosmological bounce). We perform a full simulation for the evolution of scalar perturbation, and find that the perturbation spectrum has a large-scale suppression (as expected), which is consistent with the power deficit of the cosmic microwave background (CMB) TT-spectrum at low multipoles, but unexpectedly, it also shows itself one marked lower valley. The depth of valley is relevant with the physics around the bounce scale, which is model-dependent.

Bounce universe from string-inspired Gauss-Bonnet gravity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bamba, Kazuharu; Makarenko, Andrey N.; Myagky, Alexandr N.

2015-04-01

We explore cosmology with a bounce in Gauss-Bonnet gravity where the Gauss-Bonnet invariant couples to a dynamical scalar field. In particular, the potential and and Gauss-Bonnet coupling function of the scalar field are reconstructed so that the cosmological bounce can be realized in the case that the scale factor has hyperbolic and exponential forms. Furthermore, we examine the relation between the bounce in the string (Jordan) and Einstein frames by using the conformal transformation between these conformal frames. It is shown that in general, the property of the bounce point in the string frame changes after the frame is movedmore » to the Einstein frame. Moreover, it is found that at the point in the Einstein frame corresponding to the point of the cosmological bounce in the string frame, the second derivative of the scale factor has an extreme value. In addition, it is demonstrated that at the time of the cosmological bounce in the Einstein frame, there is the Gauss-Bonnet coupling function of the scalar field, although it does not exist in the string frame.« less

Cosmological bouncing solutions in extended teleparallel gravity theories

NASA Astrophysics Data System (ADS)

de la Cruz-Dombriz, Álvaro; Farrugia, Gabriel; Said, Jackson Levi; Gómez, Diego Sáez-Chillón

2018-05-01

In the context of extended teleparallel gravity theories with a 3 +1 -dimensional Gauss-Bonnet analog term, we address the possibility of these theories reproducing several well-known cosmological bouncing scenarios in a four-dimensional Friedmann-Lemaître-Robertson-Walker geometry. We study which types of gravitational Lagrangians are capable of reconstructing bouncing solutions provided by analytical expressions for symmetric, oscillatory, superbounce, matter bounce, and singular bounce. Some of the Lagrangians discovered are analytical at the origin, having both Minkowski and Schwarzschild vacuum solutions. All these results open up the possibility for such theories to be competitive candidates of extended theories of gravity in cosmological scales.

Energy-momentum tensor of bouncing gravitons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iofa, Mikhail Z.

2015-07-14

In models of the Universe with extra dimensions gravity propagates in the whole space-time. Graviton production by matter on the brane is significant in the early hot Universe. In a model of 3-brane with matter embedded in 5D space-time conditions for gravitons emitted from the brane to the bulk to return back to the brane are found. For a given 5-momentum of graviton falling back to the brane the interval between the times of emission and return to the brane is calculated. A method to calculate contribution to the energy-momentum tensor from multiple graviton bouncings is developed. Explicit expressions formore » contributions to the energy-momentum tensor of gravitons which have made one, two and three bounces are obtained and their magnitudes are numerically calculated. These expressions are used to solve the evolution equation for dark radiation. A relation connecting reheating temperature and the scale of extra dimension is obtained. For the reheating temperature T{sub R}∼10{sup 6} GeV we estimate the scale of extra dimension μ to be of order 10{sup −9} GeV (μ{sup −1}∼10{sup −5} cm)« less

Energy-momentum tensor of bouncing gravitons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iofa, Mikhail Z., E-mail: iofa@theory.sinp.msu.ru

2015-07-01

In models of the Universe with extra dimensions gravity propagates in the whole space-time. Graviton production by matter on the brane is significant in the early hot Universe. In a model of 3-brane with matter embedded in 5D space-time conditions for gravitons emitted from the brane to the bulk to return back to the brane are found. For a given 5-momentum of graviton falling back to the brane the interval between the times of emission and return to the brane is calculated. A method to calculate contribution to the energy-momentum tensor from multiple graviton bouncings is developed. Explicit expressions formore » contributions to the energy-momentum tensor of gravitons which have made one, two and three bounces are obtained and their magnitudes are numerically calculated. These expressions are used to solve the evolution equation for dark radiation. A relation connecting reheating temperature and the scale of extra dimension is obtained. For the reheating temperature T{sub R}∼ 10{sup 6} GeV we estimate the scale of extra dimension μ to be of order 10{sup −9} GeV (μ{sup −1}∼ 10{sup −5} cm)« less

The fluid trampoline: droplets bouncing on a soap film

NASA Astrophysics Data System (ADS)

Bush, John; Gilet, Tristan

2008-11-01

We present the results of a combined experimental and theoretical investigation of droplets falling onto a horizontal soap film. Both static and vertically vibrated soap films are considered. A quasi-static description of the soap film shape yields a force-displacement relation that provides excellent agreement with experiment, and allows us to model the film as a nonlinear spring. This approach yields an accurate criterion for the transition between droplet bouncing and crossing on the static film; moreover, it allows us to rationalize the observed constancy of the contact time and scaling for the coefficient of restitution in the bouncing states. On the vibrating film, a variety of bouncing behaviours were observed, including simple and complex periodic states, multiperiodicity and chaos. A simple theoretical model is developed that captures the essential physics of the bouncing process, reproducing all observed bouncing states. Quantitative agreement between model and experiment is deduced for simple periodic modes, and qualitative agreement for more complex periodic and chaotic bouncing states.

Collective many-body bounce in the breathing-mode oscillations of a finite-temperature Tonks-Girardeau gas

NASA Astrophysics Data System (ADS)

Kheruntsyan, Karen; Atas, Yasar; Bouchoule, Isabelle; Gangardt, Dimitri

2017-04-01

We analyse the breathing-mode oscillations of a harmonically quenched Tonks-Giradeau (TG) gas using an exact finite-temperature dynamical theory. We predict a striking collective manifestation of impenetrability-a collective many-body bounce effect. The effect, while being invisible in the evolution of the in situ density profile of the gas, can be revealed through a nontrivial periodic narrowing of its momentum distribution, taking place at twice the rate of the fundamental breathing-mode frequency of oscillations of the density profile. We identify physical regimes for observing the many-body bounce and construct the respective nonequilibrium phase diagram as a function of the quench strength and the initial equilibrium temperature of the gas. We also develop a finite-temperature hydrodynamic theory of the TG gas, wherein the many-body bounce is explained by an increased thermodynamic pressure during the isentropic compression cycle, which acts as a potential barrier for the particles to bounce off.

Prostate-specific antigen bounce after intensity-modulated radiotherapy for prostate cancer.

PubMed

Sheinbein, Courtney; Teh, Bin S; Mai, Wei Y; Grant, Walter; Paulino, Arnold; Butler, E Brian

2010-09-01

To report prostate-specific antigen (PSA) bounce in patients treated with intensity-modulated radiotherapy (IMRT) alone. Previous studies have reported PSA bounce in prostate cancer patients treated with conventional radiotherapy, 3D conformal radiotherapy, and permanent seed brachytherapy. From January 1997 to July 2002, 102 patients with clinically localized prostate cancer were treated with IMRT alone. No patients received androgen ablation. PSA bounce was defined as a PSA increase of at least 0.4 ng/mL, followed by any PSA decrease. Biochemical failure was defined by both the American Society for Therapeutic Radiology and Oncology 1996 and 2006 consensus definitions. The median follow-up was 76 months. The median length of time until the first PSA bounce was 13.6 months. Thirty-three patients (32.4%) had at least 1 PSA bounce, with 25 (24.5%) having 1 bounce; 6 (5.9%), 2 bounces; and 2 (2.0%), 4 bounces. PSA bounce was not significantly associated with biochemical no evidence of disease survival, clinical stage, pretreatment PSA, Gleason combined score, prostate planning target volume, PSA nadir, or mean dose to the prostate. The rate of PSA bounce in patients aged ≤ 70 and > 70 years was 44.4% and 22.8%, respectively (P = .032). Our patient series is the first report on PSA bounce in patients treated with IMRT. Our study confirms that the majority of patients with a bouncing PSA remain biochemically and clinically free of disease with extended follow-up. Copyright © 2010 Elsevier Inc. All rights reserved.

Big bounce, slow-roll inflation, and dark energy from conformal gravity

NASA Astrophysics Data System (ADS)

Gegenberg, Jack; Rahmati, Shohreh; Seahra, Sanjeev S.

2017-02-01

We examine the cosmological sector of a gauge theory of gravity based on the SO(4,2) conformal group of Minkowski space. We allow for conventional matter coupled to the spacetime metric as well as matter coupled to the field that gauges special conformal transformations. An effective vacuum energy appears as an integration constant, and this allows us to recover the late time acceleration of the Universe. Furthermore, gravitational fields sourced by ordinary cosmological matter (i.e. dust and radiation) are significantly weakened in the very early Universe, which has the effect of replacing the big bang with a big bounce. Finally, we find that this bounce is followed by a period of nearly exponential slow roll inflation that can last long enough to explain the large scale homogeneity of the cosmic microwave background.

Non-singular bounce transitions in the multiverse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garriga, Jaume; Vilenkin, Alexander; Zhang, Jun, E-mail: jaume.garriga@ub.edu, E-mail: vilenkin@cosmos.phy.tufts.edu, E-mail: jun.zhang@tufts.edu

2013-11-01

According to classical GR, negative-energy (AdS) bubbles in the multiverse terminate in big crunch singularities. It has been conjectured, however, that the fundamental theory may resolve these singularities and replace them by non-singular bounces. Here we explore possible dynamics of such bounces using a simple modification of the Friedmann equation, which ensures that the scale factor bounces when the matter density reaches some critical value ρ{sub c}. This is combined with a simple scalar field 'landscape', where the energy barriers between different vacua are small compared to ρ{sub c}. We find that the bounce typically results in a transition tomore » another vacuum, with a scalar field displacement Δφ ∼ 1 in Planck units. If the new vacuum is AdS, we have another bounce, and so on, until the field finally transits to a positive-energy (de Sitter) vacuum. We also consider perturbations about the homogeneous solution and discuss some of their amplification mechanisms (e.g., tachyonic instability and parametric resonance). For a generic potential, these mechanisms are much less efficient than in models of slow-roll inflation. But the amplification may still be strong enough to cause the bubble to fragment into a mosaic of different vacua.« less

Growing into and out of the bouncing barrier in planetesimal formation

NASA Astrophysics Data System (ADS)

Kruss, Maximilian; Teiser, Jens; Wurm, Gerhard

2017-04-01

In recent laboratory studies the robustness of a bouncing barrier in planetesimal formation was studied with an ensemble of pre-formed compact mm-sized aggregates. Here we show that a bouncing barrier indeed evolves self-consistently by hit-and-stick from an ensemble of smaller dust aggregates. In addition, we feed small aggregates to an ensemble of larger bouncing aggregates. The stickiness temporarily increases, but the final number of aggregates still bouncing remains the same. However, feeding on the small particle supply, the size of the bouncing aggregates increases. This suggests that in the presence of a dust reservoir aggregates grow into but also out of a bouncing barrier at larger size.

Thermal fluctuations of dark matter in bouncing cosmology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Changhong, E-mail: changhongli@ynu.edu.cn

We investigate the statistical nature of the dark matter particles produced in bouncing cosmology, especially, the evolution of its thermal fluctuations. By explicitly deriving and solving the equation of motion of super-horizon mode, we fully determine the evolution of thermal perturbation of dark matter in a generic bouncing background. And we also show that the evolution of super-horizon modes is stable and will not ruin the background evolution of a generic bouncing universe till the Planck scale. Given no super-horizon thermal perturbation of dark matter appears in standard inflation scenario such as WIMP(-less) miracles, such super-horizon thermal perturbation of darkmore » matter generated during the generic bouncing universe scenario may be significant for testing and distinguishing these two scenario in near future.« less

'Bounce' Exposed

NASA Technical Reports Server (NTRS)

2004-01-01

This approximate true-color image, acquired by the Mars Exploration Rover Opportunity's panoramic camera, features the hole ground by the rover's rock abrasion tool into 'Bounce' rock. The hole measures approximately 35 centimeters (14 inches) long and 10 centimeters (4 inches) high. The depression measures 6.44 millimeters (0.25 inch) deep and about 4.5 centimeters (1.7 inches) across. The grinding procedure took place on the rover's 66th sol on Mars and lasted 2 hours and 15 minutes. A combination of limited solar power, added safety measures and the rock's jagged texture led the rock abrasion tool team to set more aggressive grinding parameters to ensure that the end result was a full circle, suitable for a thorough read from the rover's spectrometers.

Bounce's outer ring consists of the cuttings from the rock, pushed out by the brushes on the grinding instrument. The small impressions filled with red dust on the outer ring were caused by the instrument's contact mechanism, which serves to stabilize it while grinding.

This image was created using the panoramic camera's blue, green and red filters.

Bounce universe and black holes from critical Einsteinian cubic gravity

NASA Astrophysics Data System (ADS)

Feng, Xing-Hui; Huang, Hyat; Mai, Zhan-Feng; Lü, Hong

2017-11-01

We show that there exists a critical point for the coupling constants in Einsteinian cubic gravity in which the linearized equations on the maximally symmetric vacuum vanish identically. We construct an exact isotropic bounce universe in the critical theory in four dimensions. The comoving time runs from minus infinity to plus infinity, yielding a smooth universe bouncing between two de Sitter vacua. In five dimensions, we adopt a numerical approach to construct a bounce solution, in which a singularity occurs before the bounce takes place. We then construct exact anisotropic bounces that connect two isotropic de Sitter spacetimes with flat spatial sections. We further construct exact anti-de Sitter black holes in the critical theory in four and five dimensions and obtain an exact anti-de Sitter worm brane in four dimensions.

Cosmological perturbations through a non-singular ghost-condensate/Galileon bounce

DOE Office of Scientific and Technical Information (OSTI.GOV)

Battarra, Lorenzo; Koehn, Michael; Lehners, Jean-Luc

2014-07-01

We study the propagation of super-horizon cosmological perturbations in a non-singular bounce spacetime. The model we consider combines a ghost condensate with a Galileon term in order to induce a ghost-free bounce. Our calculation is performed in harmonic gauge, which ensures that the linearized equations of motion remain well-defined and non-singular throughout. We find that, despite the fact that near the bounce the speed of sound becomes imaginary, super-horizon curvature perturbations remain essentially constant across the bounce. In fact, we show that there is a time close to the bounce where curvature perturbations of all wavelengths are required to bemore » momentarily exactly constant. We relate our calculations to those performed in other gauges, and comment on the relation to previous results in the literature.« less

Big bounce with finite-time singularity: The F(R) gravity description

NASA Astrophysics Data System (ADS)

Odintsov, S. D.; Oikonomou, V. K.

An alternative to the Big Bang cosmologies is obtained by the Big Bounce cosmologies. In this paper, we study a bounce cosmology with a Type IV singularity occurring at the bouncing point in the context of F(R) modified gravity. We investigate the evolution of the Hubble radius and we examine the issue of primordial cosmological perturbations in detail. As we demonstrate, for the singular bounce, the primordial perturbations originating from the cosmological era near the bounce do not produce a scale-invariant spectrum and also the short wavelength modes after these exit the horizon, do not freeze, but grow linearly with time. After presenting the cosmological perturbations study, we discuss the viability of the singular bounce model, and our results indicate that the singular bounce must be combined with another cosmological scenario, or should be modified appropriately, in order that it leads to a viable cosmology. The study of the slow-roll parameters leads to the same result indicating that the singular bounce theory is unstable at the singularity point for certain values of the parameters. We also conformally transform the Jordan frame singular bounce, and as we demonstrate, the Einstein frame metric leads to a Big Rip singularity. Therefore, the Type IV singularity in the Jordan frame becomes a Big Rip singularity in the Einstein frame. Finally, we briefly study a generalized singular cosmological model, which contains two Type IV singularities, with quite appealing features.

Rock Bites into 'Bounce'

NASA Technical Reports Server (NTRS)

2004-01-01

This panoramic camera image from the Mars Exploration Rover Opportunity features the 6.44 millimeter (0.25 inch) deep hole ground into the rock dubbed 'Bounce' by the rover's rock abrasion tool. The tool took 2 hours and 15 minutes to grind the hole on sol 66 of the rover's journey. A combination of limited solar power and the rock's jagged texture led the rock abrasion tool team to set very aggressive grinding parameters to ensure that the end result was a full circle, suitable for a thorough read from the rover's spectrometers.

Bounce's markedly different appearance (when compared to the rocks that were previously examined in the Eagle Crater outcrop) made it a natural target for rover research. In order to achieve an ideal position from which to grind into the rock, Opportunity moved in very close with its right wheel next to Bounce. In this image, the panoramic camera on the rover's mast is looking down, catching the tip of the solar panel which partially blocks the full circle ground by the rock abrasion tool.

The outer ring consists of the cuttings from the rock, pushed out by the brushes on the grinding instrument. The dark impression at the top of the outer circle was caused by the instrument's contact mechanism which serves to stabilize it while grinding.

Eliminate the "Bounce"!

ERIC Educational Resources Information Center

Leigh, Susan

2016-01-01

The "bounce" (coined by students at Susan Leigh's last campus) refers to the amount of time students spent chasing signatures and removing often-unnecessary registration "holds" in order to attend their classes. Leigh explains that all this chaos from complex, separately housed transactional business processes has led to the…

Cosmological bounce and Genesis beyond Horndeski

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kolevatov, R.; Mironov, S.; Volkova, V.

2017-08-01

We study 'classical' bouncing and Genesis models in beyond Horndeski theory. We give an example of spatially flat bouncing solution that is non-singular and stable throughout the whole evolution. We also provide an example of stable geodesically complete Genesis with similar features. The model is arranged in such a way that the scalar field driving the cosmological evolution initially behaves like full-fledged beyond Horndeski, whereas at late times it becomes a massless scalar field minimally coupled to gravity.

Class of regular bouncing cosmologies

NASA Astrophysics Data System (ADS)

Vasilić, Milovan

2017-06-01

In this paper, I construct a class of everywhere regular geometric sigma models that possess bouncing solutions. Precisely, I show that every bouncing metric can be made a solution of such a model. My previous attempt to do so by employing one scalar field has failed due to the appearance of harmful singularities near the bounce. In this work, I use four scalar fields to construct a class of geometric sigma models which are free of singularities. The models within the class are parametrized by their background geometries. I prove that, whatever background is chosen, the dynamics of its small perturbations is classically stable on the whole time axis. Contrary to what one expects from the structure of the initial Lagrangian, the physics of background fluctuations is found to carry two tensor, two vector, and two scalar degrees of freedom. The graviton mass, which naturally appears in these models, is shown to be several orders of magnitude smaller than its experimental bound. I provide three simple examples to demonstrate how this is done in practice. In particular, I show that graviton mass can be made arbitrarily small.

Prostate specific antigen bounce is related to overall survival in prostate brachytherapy.

PubMed

Hinnen, Karel A; Monninkhof, Evelyn M; Battermann, Jan J; van Roermund, Joep G H; Frank, Steven J; van Vulpen, Marco

2012-02-01

To investigate the association between prostate specific antigen (PSA) bounce and disease outcome after prostate brachytherapy. We analyzed 975 patients treated with (125)I implantation monotherapy between 1992 and 2006. All patients had tumor Stage ≤ 2c, Gleason score ≤ 7 prostate cancer, a minimum follow-up of 2 years with at least four PSA measurements, and no biochemical failure in the first 2 years. Median follow-up was 6 years. Bounce was defined as a PSA elevation of +0.2 ng/mL with subsequent decrease to previous nadir. We used the Phoenix +2 ng/mL definition for biochemical failure. Additional endpoints were disease-specific and overall survival. Multivariate Cox regression analysis was performed to adjust for potential confounding factors. Bounce occurred in 32% of patients, with a median time to bounce of 1.6 years. More than 90% of bounces took place in the first 3 years after treatment and had disappeared within 2 years of onset. Ten-year freedom from biochemical failure, disease-specific survival, and overall survival rates were, respectively, 90%, 99%, and 88% for the bounce group and 70%, 93%, and 82% for the no-bounce group. Only 1 patient (0.3%) died of prostate cancer in the bounce group, compared with 40 patients (6.1%) in the no-bounce group. Adjusted for confounding, a 70% biochemical failure risk reduction was observed for patients experiencing a bounce (hazard ratio 0.31; 95% confidence interval 0.20-0.48). A PSA bounce after prostate brachytherapy is strongly related to better outcome in terms of biochemical failure, disease-specific survival, and overall survival. Copyright © 2012 Elsevier Inc. All rights reserved.

Bianchi IX dynamics in bouncing cosmologies: homoclinic chaos and the BKL conjecture

NASA Astrophysics Data System (ADS)

Maier, Rodrigo; Damião Soares, Ivano; Valentino Tonini, Eduardo

2015-12-01

We examine the dynamics of a Bianchi IX model with three scale factors on a 4-dim Lorentzian brane embedded in a 5-dim conformally flat empty bulk with a timelike extra dimension. The matter content is a pressureless perfect fluid restricted to the brane, with the embedding consistently satisfying the Gauss-Codazzi equations. The 4-dim Einstein equations on the brane reduce to a 6-dim Hamiltonian dynamical system with additional terms (due to the bulk-brane interaction) that avoid the singularity and implement nonsingular bounces in the model. We examine the complex Bianchi IX dynamics in its approach to the neighborhood of the bounce which replaces the cosmological singularity of general relativity. The phase space of the model presents (i) two critical points (a saddle-center-center and a center-center-center) in a finite region of phase space, (ii) two asymptotic de Sitter critical points at infinity, one acting as an attractor to late-time acceleration and (iii) a 2-dim invariant plane, which together organize the dynamics of the phase space. The saddle-center-center engenders in the phase space the topology of stable and unstable 4-dim cylinders R × S 3, where R is a saddle direction and S 3 is the center manifold of unstable periodic orbits, the latter being the nonlinear extension of the center-center sector. By a proper canonical transformation the degrees of freedom of the dynamics are separated into one degree connected with the expansion/contraction of the scales of the model, and two rotational degrees of freedom associated with the center manifold S 3. The typical dynamical flow is thus an oscillatory mode about the orbits of the invariant plane. The stable and unstable cylinders are spanned by oscillatory orbits about the separatrix towards the bounce, leading to the homoclinic transversal intersection of the cylinders, as shown numerically in two distinct simulations. The homoclinic intersection manifold has the topology of R × S 2 consisting of

Generalized Galileons: instabilities of bouncing and Genesis cosmologies and modified Genesis

NASA Astrophysics Data System (ADS)

Libanov, M.; Mironov, S.; Rubakov, V.

2016-08-01

We study spatially flat bouncing cosmologies and models with the early-time Genesis epoch in a popular class of generalized Galileon theories. We ask whether there exist solutions of these types which are free of gradient and ghost instabilities. We find that irrespectively of the forms of the Lagrangian functions, the bouncing models either are plagued with these instabilities or have singularities. The same result holds for the original Genesis model and its variants in which the scale factor tends to a constant as t → -∞. The result remains valid in theories with additional matter that obeys the Null Energy Condition and interacts with the Galileon only gravitationally. We propose a modified Genesis model which evades our no-go argument and give an explicit example of healthy cosmology that connects the modified Genesis epoch with kination (the epoch still driven by the Galileon field, which is a conventional massless scalar field at that stage).

Generalized Galileons: instabilities of bouncing and Genesis cosmologies and modified Genesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Libanov, M.; Moscow Institute of Physics and Technology,Institutskii per. 9, 141700 Dolgoprudny, Moscow Region; Mironov, S.

2016-08-18

We study spatially flat bouncing cosmologies and models with the early-time Genesis epoch in a popular class of generalized Galileon theories. We ask whether there exist solutions of these types which are free of gradient and ghost instabilities. We find that irrespectively of the forms of the Lagrangian functions, the bouncing models either are plagued with these instabilities or have singularities. The same result holds for the original Genesis model and its variants in which the scale factor tends to a constant as t→−∞. The result remains valid in theories with additional matter that obeys the Null Energy Condition andmore » interacts with the Galileon only gravitationally. We propose a modified Genesis model which evades our no-go argument and give an explicit example of healthy cosmology that connects the modified Genesis epoch with kination (the epoch still driven by the Galileon field, which is a conventional massless scalar field at that stage).« less

Bounce frequency fishbone analysis

NASA Astrophysics Data System (ADS)

White, Roscoe; Fredrickson, Eric; Chen, Liu

2002-11-01

Large amplitude bursting modes are observed on NSTX, which are identified as bounce frequency fishbone modes(PDX Group, Princeton Plasma Physics Lab, Phys Rev. Lett) 50, 891 (1983)^,(L. Chen, R. B. White, and M. N. Rosenbluth Phys Rev. Lett) 52, 1122 (1984). The identification is carried out using numerical equilibria obtained from TRANSP( R. V. Budny, M. G. Bell A. C. Janos et al), Nucl Fusion 35, 1497 (1995) and the numerical guiding center code ORBIT( R.B. White, Phys. Fluids B 2)(4), 845 (1990). These modes are important for high energy particle distributions which have large average bounce angle, such as the nearly tangentially injected beam ions in NSTX and isotropic alpha particle distributions. They are particularly important in high q low shear advanced plasma scenarios. Different ignited plasma scenarios are investigated with these modes in view.

The Bounce Meter

ERIC Educational Resources Information Center

Nunn, John

2014-01-01

This paper describes how a microphone plugged in to a normal computer can be used to record the impacts of a ball bouncing on a table. The intervals between these impacts represent the "time of flight" of the ball. Since some energy is lost in each rebound, the time intervals get progressively smaller. Through calculation it is possible…

Magnetogenesis in matter—Ekpyrotic bouncing cosmology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koley, Ratna; Samtani, Sidhartha, E-mail: ratna.physics@presiuniv.ac.in, E-mail: samtanisidhartha@gmail.com

In the recent past there have been many attempts to associate the generation of primordial magnetic seed fields with the inflationary era, but with limited success. We thus take a different approach by using a model for nonsingular bouncing cosmology. A coupling of the electromagnetic Lagrangian F {sub μν} F {sup μν} with a non background scalar field has been considered for the breaking of conformal invariance. We have shown that non singular bouncing cosmology supports magnetogenesis evading the long standing back reaction and strong coupling problems which have plagued inflationary magnetogenesis. In this model, we have achieved a scalemore » invariant power spectrum for the parameter range compatible with observed CMB anisotropies. The desired strength of the magnetic field has also been obtained that goes in accordance with present observations. It is also important to note that no BKL instability arises within this parameter range. The energy scales for different stages of evolution of the bouncing model are so chosen that they solve certain problems of standard Big Bang cosmology as well.« less

Superhydrophobic-like tunable droplet bouncing on slippery liquid interfaces

PubMed Central

Hao, Chonglei; Li, Jing; Liu, Yuan; Zhou, Xiaofeng; Liu, Yahua; Liu, Rong; Che, Lufeng; Zhou, Wenzhong; Sun, Dong; Li, Lawrence; Xu, Lei; Wang, Zuankai

2015-01-01

Droplet impacting on solid or liquid interfaces is a ubiquitous phenomenon in nature. Although complete rebound of droplets is widely observed on superhydrophobic surfaces, the bouncing of droplets on liquid is usually vulnerable due to easy collapse of entrapped air pocket underneath the impinging droplet. Here, we report a superhydrophobic-like bouncing regime on thin liquid film, characterized by the contact time, the spreading dynamics, and the restitution coefficient independent of underlying liquid film. Through experimental exploration and theoretical analysis, we demonstrate that the manifestation of such a superhydrophobic-like bouncing necessitates an intricate interplay between the Weber number, the thickness and viscosity of liquid film. Such insights allow us to tune the droplet behaviours in a well-controlled fashion. We anticipate that the combination of superhydrophobic-like bouncing with inherent advantages of emerging slippery liquid interfaces will find a wide range of applications. PMID:26250403

Running humans attain optimal elastic bounce in their teens.

PubMed

Legramandi, Mario A; Schepens, Bénédicte; Cavagna, Giovanni A

2013-01-01

In an ideal elastic bounce of the body, the time during which mechanical energy is released during the push equals the time during which mechanical energy is absorbed during the brake, and the maximal upward velocity attained by the center of mass equals the maximal downward velocity. Deviations from this ideal model, prolonged push duration and lower upward velocity, have found to be greater in older than in younger adult humans. However it is not known how similarity to the elastic bounce changes during growth and whether an optimal elastic bounce is attained at some age. Here we show that similarity with the elastic bounce is minimal at 2 years and increases with age attaining a maximum at 13-16 years, concomitant with a mirror sixfold decrease of the impact deceleration peak following collision of the foot with the ground. These trends slowly reverse during the course of the lifespan.

Running humans attain optimal elastic bounce in their teens

PubMed Central

Legramandi, Mario A.; Schepens, Bénédicte; Cavagna, Giovanni A.

2013-01-01

In an ideal elastic bounce of the body, the time during which mechanical energy is released during the push equals the time during which mechanical energy is absorbed during the brake, and the maximal upward velocity attained by the center of mass equals the maximal downward velocity. Deviations from this ideal model, prolonged push duration and lower upward velocity, have found to be greater in older than in younger adult humans. However it is not known how similarity to the elastic bounce changes during growth and whether an optimal elastic bounce is attained at some age. Here we show that similarity with the elastic bounce is minimal at 2 years and increases with age attaining a maximum at 13-16 years, concomitant with a mirror sixfold decrease of the impact deceleration peak following collision of the foot with the ground. These trends slowly reverse during the course of the lifespan. PMID:23419705

A critical review of classical bouncing cosmologies

NASA Astrophysics Data System (ADS)

Battefeld, Diana; Peter, Patrick

2015-04-01

Given the proliferation of bouncing models in recent years, we gather and critically assess these proposals in a comprehensive review. The PLANCK data shows an unmistakably red, quasi scale-invariant, purely adiabatic primordial power spectrum and no primary non-Gaussianities. While these observations are consistent with inflationary predictions, bouncing cosmologies aspire to provide an alternative framework to explain them. Such models face many problems, both of the purely theoretical kind, such as the necessity of violating the NEC and instabilities, and at the cosmological application level, as exemplified by the possible presence of shear. We provide a pedagogical introduction to these problems and also assess the fitness of different proposals with respect to the data. For example, many models predict a slightly blue spectrum and must be fine-tuned to generate a red spectral index; as a side effect, large non-Gaussianities often result. We highlight several promising attempts to violate the NEC without introducing dangerous instabilities at the classical and/or quantum level. If primordial gravitational waves are observed, certain bouncing cosmologies, such as the cyclic scenario, are in trouble, while others remain valid. We conclude that, while most bouncing cosmologies are far from providing an alternative to the inflationary paradigm, a handful of interesting proposals have surfaced, which warrant further research. The constraints and lessons learned as laid out in this review might guide future research.

General background conditions for K-bounce and adiabaticity

NASA Astrophysics Data System (ADS)

Romano, Antonio Enea

2017-03-01

We study the background conditions for a bounce uniquely driven by a single scalar field model with a generalized kinetic term K( X), without any additional matter field. At the background level we impose the existence of two turning points where the derivative of the Hubble parameter H changes sign and of a bounce point where the Hubble parameter vanishes. We find the conditions for K( X) and the potential which ensure the above requirements. We then give the examples of two models constructed according to these conditions. One is based on a quadratic K( X), and the other on a K( X) which is avoiding divergences of the second time derivative of the scalar field, which may otherwise occur. An appropriate choice of the initial conditions can lead to a sequence of consecutive bounces, or oscillations of H. In the region where these models have a constant potential they are adiabatic on any scale and because of this they may not conserve curvature perturbations on super-horizon scales. While at the perturbation level one class of models is free from ghosts and singularities of the classical equations of motion, in general gradient instabilities are present around the bounce time, because the sign of the squared speed of sound is opposite to the sign of the time derivative of H. We discuss how this kind of instabilities could be avoided by modifying the Lagrangian by introducing Galilean terms in order to prevent a negative squared speed of sound around the bounce.

Study on bouncing motion of a water drop collision on superhydrophobic surface under icing conditions

NASA Astrophysics Data System (ADS)

Maeda, Tetsuro; Morita, Katsuaki; Kimura, Shigeo

2017-11-01

When micro droplets in the air are supercooled and collide with the object, they froze on the surface at the time of a collision and can be defined as icing. If supercooled water droplets collide with an airfoil of an aircraft in flight and shape changes, there is a danger of losing lift and falling. Recently, the ice protection system using a heater and Anti- / Deicing (superhydrophobic) coating is focused. In this system, colliding water droplets are melted by the heat of the heater at the tip of the blade, and the water droplet is bounced by the aerodynamic force on the rear superhydrophobic coating. Thus, it prevents the phenomenon of icing again at the back of the wing (runback ice). Therefore, it is possible to suppress power consumption of the electric heater. In that system, it is important to withdraw water droplets at an extremely superhydrophobic surface at an early stage. However, research on bouncing phenomenon on superhydrophobic surface under icing conditions are not done much now. Therefore, in our research, we focus on one drop supercooled water droplet that collides with the superhydrophobic surface in the icing phenomenon, and aim to follow that phenomenon. In this report, the contact time is defined as the time from collision of a water droplet to bouncing from the superhydrophobic surface, and various parameters (temperature, speed, and diameter) on water droplets under icing conditions are set as the water drop bouncing time (contact time) of the product.

Three examples of quantum dynamics on the half-line with smooth bouncing

NASA Astrophysics Data System (ADS)

Almeida, C. R.; Bergeron, H.; Gazeau, J.-P.; Scardua, A. C.

2018-05-01

This article is an introductory presentation of the quantization of the half-plane based on affine coherent states (ACS). The half-plane carries a natural affine symmetry, i.e. it is a homogeneous space for the 1d-affine group, and it is viewed as the phase space for the dynamics of a positive physical quantity evolving with time. Its affine symmetry is preserved due to the covariance of this type of quantization. We promote the interest of such a procedure for transforming a classical model into a quantum one, since the singularity at the origin is systematically removed, and the arbitrariness of boundary conditions for the Schrödinger operator can be easily overcome. We explain some important mathematical aspects of the method. Three elementary examples of applications are presented, the quantum breathing of a massive sphere, the quantum smooth bouncing of a charged sphere, and a smooth bouncing of "dust" sphere as a simple model of quantum Newtonian cosmology.

"Bounce at the Bell": a novel program of short bouts of exercise improves proximal femur bone mass in early pubertal children

PubMed Central

McKay, H; MacLean, L; Petit, M; MacKelvie-O'Brien, K; Janssen, P; Beck, T; Khan, K

2005-01-01

Objectives: To examine the effects of a simple and inexpensive physical activity intervention on change in bone mass and structure in school aged children. Methods: Fifty one children (n = 23 boys and 28 girls; mean age 10.1 years) participated in "Bounce at the Bell" which consisted of 10 counter-movement jumps 3x per day (total ∼3 min/day). Controls were 71 matched children who followed usual school practice. We assessed dietary calcium, physical activity, physical performance, and anthropometry in September and after 8 months of intervention (June). We measured bone mineral content (BMC) and bone area at the lumbar spine, total body, and proximal femur. Proximal femur scans were also analysed for bone geometry and structural strength using the hip structural analysis program. Lean and fat mass (g) were also calculated. Results: Groups were similar at baseline and did not differ in weight, height, total body, lumbar spine, proximal femur, or femoral neck BMC. Control children had a greater increase in adjusted total body BMC (1.4%). Intervention children gained significantly more BMC at the total proximal femur (2%) and the intertrochanteric region (27%). Change in bone structural parameters did not differ between groups. Conclusions: This novel, easily implemented exercise program, took only a few minutes each day and enhanced bone mass at the weight bearing proximal femur in early pubertal children. A large, randomised study of boys and girls should be undertaken powered to test the effectiveness of Bounce at the Bell in children at different stages of maturity, and in boys and girls independently. PMID:16046335

BounceBack capsules for reduction of DOMS after eccentric exercise: a randomized, double-blind, placebo-controlled, crossover pilot study.

PubMed

Udani, Jay K; Singh, Betsy B; Singh, Vijay J; Sandoval, Elizabeth

2009-06-05

Delayed onset muscle soreness (DOMS) is muscle pain and discomfort experienced approximately one to three days after exercise. DOMS is thought to be a result of microscopic muscle fiber tears that occur more commonly after eccentric exercise rather than concentric exercise. This study sought to test the efficacy of a proprietary dietary supplement, BounceBack, to alleviate the severity of DOMS after standardized eccentric exercise. The study was a randomized, double-blind, placebo-controlled, crossover study. Ten healthy community-dwelling untrained subjects, ranging in age from 18-45 years, were enrolled. Mean differences within and between groups were assessed inferentially at each data collection time-point using t-tests for all outcome measures. In this controlled pilot study, intake of BounceBack capsules for 30 days resulted in a significant reduction in standardized measures of pain and tenderness post-eccentric exercise compared to the placebo group. There were trends towards reductions in plasma indicators of inflammation (high sensitivity C-reactive protein) and muscle damage (creatine phosphokinase and myoglobin). BounceBack capsules were able to significantly reduce standardized measures of pain and tenderness at several post-eccentric exercise time points in comparison to placebo. The differences in the serological markers of DOMS, while not statistically significant, appear to support the clinical findings. The product appears to have a good safety profile and further study with a larger sample size is warranted based on the current results.

BounceBack™ capsules for reduction of DOMS after eccentric exercise: a randomized, double-blind, placebo-controlled, crossover pilot study

PubMed Central

Udani, Jay K; Singh, Betsy B; Singh, Vijay J; Sandoval, Elizabeth

2009-01-01

Background Delayed onset muscle soreness (DOMS) is muscle pain and discomfort experienced approximately one to three days after exercise. DOMS is thought to be a result of microscopic muscle fiber tears that occur more commonly after eccentric exercise rather than concentric exercise. This study sought to test the efficacy of a proprietary dietary supplement, BounceBack™, to alleviate the severity of DOMS after standardized eccentric exercise. Methods The study was a randomized, double-blind, placebo-controlled, crossover study. Ten healthy community-dwelling untrained subjects, ranging in age from 18–45 years, were enrolled. Mean differences within and between groups were assessed inferentially at each data collection time-point using t-tests for all outcome measures. Results In this controlled pilot study, intake of BounceBack™ capsules for 30 days resulted in a significant reduction in standardized measures of pain and tenderness post-eccentric exercise compared to the placebo group. There were trends towards reductions in plasma indicators of inflammation (high sensitivity C-reactive protein) and muscle damage (creatine phosphokinase and myoglobin). Conclusion BounceBack™ capsules were able to significantly reduce standardized measures of pain and tenderness at several post-eccentric exercise time points in comparison to placebo. The differences in the serological markers of DOMS, while not statistically significant, appear to support the clinical findings. The product appears to have a good safety profile and further study with a larger sample size is warranted based on the current results. PMID:19500355

Passive vs. Active Control of Rhythmic Ball Bouncing: The Role of Visual Information

ERIC Educational Resources Information Center

Siegler, Isabelle A.; Bardy, Benoit G.; Warren, William H.

2010-01-01

The simple task of bouncing a ball on a racket offers a model system for studying how human actors exploit the physics and information of the environment to control their behavior. Previous work shows that people take advantage of a passively stable solution for ball bouncing but can also use perceptual information to actively stabilize bouncing.…

Phenomenology of bouncing black holes in quantum gravity: a closer look

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barrau, Aurélien; Bolliet, Boris; Weimer, Celine

2016-02-01

It was recently shown that black holes could be bouncing stars as a consequence of quantum gravity. We investigate the astrophysical signals implied by this hypothesis, focusing on primordial black holes. We consider different possible bounce times and study the integrated diffuse emission.

Bounce Rock Dimple

NASA Technical Reports Server (NTRS)

2004-01-01

This panoramic camera image shows the hole drilled by the Mars Exploration Rover Opportunity's rock abrasion tool into the rock dubbed 'Bounce' on Sol 65 of the rover's journey. The tool drilled about 7 millimeters (0.3 inches) into the rock and generated small piles of 'tailings' or rock dust around the central hole, which is about 4.5 centimeters (1.7 inches) across. The image from sol 66 of the mission was acquired using the panoramic camera's 430 nanometer filter.

Past incompleteness of a bouncing multiverse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vilenkin, Alexander; Zhang, Jun, E-mail: vilenkin@cosmos.phy.tufts.edu, E-mail: jun.zhang@tufts.edu

2014-06-01

According to classical GR, Anti-de Sitter (AdS) bubbles in the multiverse terminate in big crunch singularities. It has been conjectured, however, that the fundamental theory may resolve these singularities and replace them by nonsingular bounces. This may have important implications for the beginning of the multiverse. Geodesics in cosmological spacetimes are known to be past-incomplete, as long as the average expansion rate along the geodesic is positive, but it is not clear that the latter condition is satisfied if the geodesic repeatedly passes through crunching AdS bubbles. We investigate this issue in a simple multiverse model, where the spacetime consistsmore » of a patchwork of FRW regions. The conclusion is that the spacetime is still past-incomplete, even in the presence of AdS bounces.« less

Behavior of hollow balls containing granules bouncing repeatedly off the ground

NASA Astrophysics Data System (ADS)

Hu, Min; Mu, Qing-song; Luo, Ning; Li, Gang; Peng, Ning-bo

2013-07-01

An experimental study of the behavior of hollow balls filled with some granules (mung beans or millets) bouncing repeatedly off a static flat horizontal surface is presented. We observed that the bounce number of the ball is limited and decreases regularly with an increasing number of granules. Moreover, for two balls containing a different kind of granules, their bounce numbers are basically equal when the two balls have the same mass of granules. While there is no clear relationship between the first rebound height of one ball and the number of granules, there appears an exponential decay of the second rebound height with an increase of the granule number. Furthermore, a two-dimensional numerical model has been created to find out the law of the ball's rebound height and the dissipation law of the granule nested system. A generalized prediction equation to reasonably explain the law of the bounce number has also been proposed.

Enhanced ground bounce noise reduction in a low-leakage CMOS multiplier

NASA Astrophysics Data System (ADS)

Verma, Bipin Kumar; Akashe, Shyam; Sharma, Sanjay

2015-09-01

In this paper, various parameters are used to reduce leakage power, leakage current and noise margin of circuits to enhance their performance. A multiplier is proposed with low-leakage current and low ground bounce noise for the microprocessor, digital signal processors (DSP) and graphics engines. The ground bounce noise problem appears when a conventional power-gating circuit transits from sleep-to-active mode. This paper discusses a reduction in leakage current in the stacking power-gating technique by three modes - sleep, active and sleep-to-active. The simulation results are performed on a 4 × 4 carry-save multiplier for leakage current, active power, leakage power and ground bounce noise, and comparison made for different nanoscales. Ground bounce noise is limited to 90%. The leakage current of the circuit is decimated up to 80% and the active power is reduced to 31%. We performed simulations using cadence virtuoso 180 and 45 nm at room temperature at various supply voltages.

Characteristics of adverse drug reactions in a vemurafenib early post-marketing phase vigilance study in Japan.

PubMed

Uhara, H; Kiyohara, Y; Tsuda, A; Takata, M; Yamazaki, N

2018-02-01

Post-approval research or monitoring is important to determine real-world safety of new products; however, evidence is scant for vemurafenib in Japanese patients. In Japan, a unique system is officially obligated to investigate post-approval safety. Here we report the first adverse drug reaction (ADR) data from vemurafenib-treated Japanese patients with metastatic melanoma. Data were collected in an early post-marketing phase vigilance (EPPV) study. ADRs were events for which a causal relationship with vemurafenib could not be ruled out or was unknown. ADR data were collected for patients treated with vemurafenib (960 mg bid) between 26 February and 25 August 2015. Among 95 patients, 46 patients had 118 ADRs (24 serious ADRs in 13 patients). The most common serious ADRs were hypersensitivity (n = 1; 3 events), arthralgia (n = 2; 2 events), pyrexia (n = 2; 2 events) and drug eruption (n = 2; 2 events). Seven patients had serious skin disorders or hypersensitivity, six of whom had prior anti-programmed cell death-1 (PD-1) antibodies 5-35 days before starting vemurafenib. ADR reports of serious skin disorders appeared to be collected more rapidly than previously reported. Cutaneous squamous cell carcinoma developed in only one patient. EPPV in Japanese vemurafenib-treated patients identified no new safety signals. The most serious skin and hypersensitivity ADRs occurred in patients with prior anti-PD-1 exposure. Cutaneous squamous cell carcinoma appeared to be rare in Japanese patients. Further research is needed to clarify whether prior treatment with anti-PD-1 agents or racial differences affect the characteristic profile of cutaneous ADRs in Japanese patients.

Safety evaluation of laninamivir octanoate hydrate through analysis of adverse events reported during early post-marketing phase vigilance.

PubMed

Nakano, Takashi; Okumura, Akihisa; Tanabe, Takuya; Niwa, Shimpei; Fukushima, Masato; Yonemochi, Rie; Eda, Hisano; Tsutsumi, Hiroyuki

2013-06-01

Abnormal behavior and delirium are common in children with influenza. While abnormal behavior and delirium are considered to be associated with influenza encephalopathy, an increased risk of such neuropsychiatric symptoms in patients receiving neuraminidase inhibitor treatment is suspected. Laninamivir octanoate hydrate, recently approved in Japan, is a long-acting neuraminidase inhibitor. It is important to establish a safety profile for laninamivir early, based on post-marketing experiences. Spontaneous safety reports collected in the early post-marketing phase vigilance were analyzed. Adverse events of interest such as abnormal behavior/delirium, dizziness/vertigo, respiratory disorders, shock/syncope, and any other serious events were intensively reviewed by the Safety Evaluation Committee. Abnormal behavior/delirium was a frequently reported event. Almost all the reported cases were considered to be due to influenza and not laninamivir. There were 32 cases of abnormal behavior/delirium that could lead to dangerous accidents, and these were observed more frequently in males and teenagers. Syncope probably related to the act of inhalation per se of laninamivir was reported during this survey. This safety review revealed that the safety profile of laninamivir for abnormal behavior/delirium and syncope was similar to that of other neuraminidase inhibitors. As stated in the labeling, teenage patients inhaling laninamivir should remain under constant parental supervision for at least 2 days and should be closely monitored for behavioral changes to prevent serious accidents associated with abnormal behavior/delirium. Furthermore, to avoid syncope because of inhalation, patients should be instructed to inhale in a relaxed sitting position.

Bouncing Ball with a Uniformly Varying Velocity in a Metronome Synchronization Task.

PubMed

Huang, Yingyu; Gu, Li; Yang, Junkai; Wu, Xiang

2017-09-21

Sensorimotor synchronization (SMS), a fundamental human ability to coordinate movements with external rhythms, has long been thought to be modality specific. In the canonical metronome synchronization task that requires tapping a finger along with an isochronous sequence, a well-established finding is that synchronization is much more stable to an auditory sequence consisting of auditory tones than to a visual sequence consisting of visual flashes. However, recent studies have shown that periodically moving visual stimuli can substantially improve synchronization compared with visual flashes. In particular, synchronization of a visual bouncing ball that has a uniformly varying velocity was found to be not less stable than synchronization of auditory tones. Here, the current protocol describes the application of the bouncing ball with a uniformly varying velocity in a metronome synchronization task. The usage of the bouncing ball in sequences with different inter-onset intervals (IOI) is included. The representative results illustrate synchronization performance of the bouncing ball, as compared with the performances of auditory tones and visual flashes. Given its comparable synchronization performance to that of auditory tones, the bouncing ball is of particular importance for addressing the current research topic of whether modality-specific mechanisms underlay SMS.

Spontaneous jumping, bouncing and trampolining of hydrogel drops on a heated plate.

PubMed

Pham, Jonathan T; Paven, Maxime; Wooh, Sanghyuk; Kajiya, Tadashi; Butt, Hans-Jürgen; Vollmer, Doris

2017-10-13

The contact between liquid drops and hot solid surfaces is of practical importance for industrial processes, such as thermal spraying and spray cooling. The contact and bouncing of solid spheres is also an important event encountered in ball milling, powder processing, and everyday activities, such as ball sports. Using high speed video microscopy, we demonstrate that hydrogel drops, initially at rest on a surface, spontaneously jump upon rapid heating and continue to bounce with increasing amplitudes. Jumping is governed by the surface wettability, surface temperature, hydrogel elasticity, and adhesion. A combination of low-adhesion impact behavior and fast water vapor formation supports continuous bouncing and trampolining. Our results illustrate how the interplay between solid and liquid characteristics of hydrogels results in intriguing dynamics, as reflected by spontaneous jumping, bouncing, trampolining, and extremely short contact times.Drops of liquid on a hot surface can exhibit fascinating behaviour such as the Leidenfrost effect in which drops hover on a vapour layer. Here Pham et al. show that when hydrogel drops are placed on a rapidly heated plate they bounce to increasing heights even if they were initially at rest.

Stable Liquid Jets Bouncing off Soft Gels

NASA Astrophysics Data System (ADS)

Daniel, Dan; Yao, Xi; Aizenberg, Joanna

2018-01-01

A liquid jet can stably bounce off a sufficiently soft gel by following the contour of the dimple created upon impact. This new phenomenon is insensitive to the wetting properties of the gels and was observed for different liquids over a wide range of surface tensions, γ =24 -72 mN /m . In contrast, other jet rebound phenomena are typically sensitive to γ : only a high γ jet rebounds off a hard solid (e.g. superhydrophobic surface) and only a low γ jet bounces off a liquid bath. This is because an air layer must be stabilized between the two interfaces. For a soft gel, no air layer is necessary and the jet rebound remains stable even when there is direct liquid-gel contact.

The scale invariant power spectrum of the primordial curvature perturbations from the coupled scalar tachyon bounce cosmos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Changhong; Cheung, Yeuk-Kwan E., E-mail: chellifegood@gmail.com, E-mail: cheung@nju.edu.cn

2014-07-01

We investigate the spectrum of cosmological perturbations in a bounce cosmos modeled by a scalar field coupled to the string tachyon field (CSTB cosmos). By explicit computation of its primordial spectral index we show the power spectrum of curvature perturbations, generated during the tachyon matter dominated contraction phase, to be nearly scale invariant. We propose a unified parameter space for a systematic study of inflationary and bounce cosmologies. The CSTB cosmos is dual-in Wands's sense-to slow-roll inflation as can be visualized with the aid of this parameter space. Guaranteed by the dynamical attractor behavior of the CSTB Cosmos, the scalemore » invariance of its power spectrum is free of the fine-tuning problem, in contrast to the slow-roll inflation model.« less

Running of the scalar spectral index in bouncing cosmologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lehners, Jean-Luc; Wilson-Ewing, Edward, E-mail: jean-luc.lehners@aei.mpg.de, E-mail: wilson-ewing@aei.mpg.de

We calculate the running of the scalar index in the ekpyrotic and matter bounce cosmological scenarios, and find that it is typically negative for ekpyrotic models, while it is typically positive for realizations of the matter bounce where multiple fields are present. This can be compared to inflation, where the observationally preferred models typically predict a negative running. The magnitude of the running is expected to be between 10{sup −4} and up to 10{sup −2}, leading in some cases to interesting expectations for near-future observations.

Bouncing droplets on a billiard table.

PubMed

Shirokoff, David

2013-03-01

In a set of experiments, Couder et al. demonstrate that an oscillating fluid bed may propagate a bouncing droplet through the guidance of the surface waves. I present a dynamical systems model, in the form of an iterative map, for a droplet on an oscillating bath. I examine the droplet bifurcation from bouncing to walking, and prescribe general requirements for the surface wave to support stable walking states. I show that in addition to walking, there is a region of large forcing that may support the chaotic motion of the droplet. Using the map, I then investigate the droplet trajectories in a square (billiard ball) domain. I show that in large domains, the long time trajectories are either non-periodic dense curves or approach a quasiperiodic orbit. In contrast, in small domains, at low forcing, trajectories tend to approach an array of circular attracting sets. As the forcing increases, the attracting sets break down and the droplet travels throughout space.

XPATCH: a high-frequency electromagnetic scattering prediction code using shooting and bouncing rays

NASA Astrophysics Data System (ADS)

Hazlett, Michael; Andersh, Dennis J.; Lee, Shung W.; Ling, Hao; Yu, C. L.

1995-06-01

This paper describes an electromagnetic computer prediction code for generating radar cross section (RCS), time domain signatures, and synthetic aperture radar (SAR) images of realistic 3-D vehicles. The vehicle, typically an airplane or a ground vehicle, is represented by a computer-aided design (CAD) file with triangular facets, curved surfaces, or solid geometries. The computer code, XPATCH, based on the shooting and bouncing ray technique, is used to calculate the polarimetric radar return from the vehicles represented by these different CAD files. XPATCH computes the first-bounce physical optics plus the physical theory of diffraction contributions and the multi-bounce ray contributions for complex vehicles with materials. It has been found that the multi-bounce contributions are crucial for many aspect angles of all classes of vehicles. Without the multi-bounce calculations, the radar return is typically 10 to 15 dB too low. Examples of predicted range profiles, SAR imagery, and radar cross sections (RCS) for several different geometries are compared with measured data to demonstrate the quality of the predictions. The comparisons are from the UHF through the Ka frequency ranges. Recent enhancements to XPATCH for MMW applications and target Doppler predictions are also presented.

Modelling the normal bouncing dynamics of spheres in a viscous fluid

NASA Astrophysics Data System (ADS)

Izard, Edouard; Lacaze, Laurent; Bonometti, Thomas

2017-06-01

Bouncing motions of spheres in a viscous fluid are numerically investigated by an immersed boundary method to resolve the fluid flow around solids which is combined to a discrete element method for the particles motion and contact resolution. Two well-known configurations of bouncing are considered: the normal bouncing of a sphere on a wall in a viscous fluid and a normal particle-particle bouncing in a fluid. Previous experiments have shown the effective restitution coefficient to be a function of a single parameter, namely the Stokes number which compares the inertia of the solid particle with the fluid viscous dissipation. The present simulations show a good agreement with experimental observations for the whole range of investigated parameters. However, a new definition of the coefficient of restitution presented here shows a dependence on the Stokes number as in previous works but, in addition, on the fluid to particle density ratio. It allows to identify the viscous, inertial and dry regimes as found in experiments of immersed granular avalanches of Courrech du Pont et al. Phys. Rev. Lett. 90, 044301 (2003), e.g. in a multi-particle configuration.

The behavior of bouncing disks and pizza tossing

NASA Astrophysics Data System (ADS)

Liu, K.-C.; Friend, J.; Yeo, L.

2009-03-01

We investigate the dynamics of a disk bouncing on a vibrating platform - a variation of the classic bouncing ball problem - that captures the physics of pizza tossing and the operation of certain standing-wave ultrasonic motors (SWUMs). The system's dynamics explains why certain tossing motions are used by dough-toss performers for different tricks: a helical trajectory is used in single tosses because it maximizes energy efficiency and the dough's airborne rotational speed, a semi-elliptical motion is used in multiple tosses because it is easier for maintaining dough rotation at the maximum rotational speed. The system's bifurcation diagram and basins of attraction also informs SWUM designers about the optimal design for high speed and minimal sensitivity to perturbation.

Magnetic resonance characterization of septal bounce: findings of blood impact physiology.

PubMed

Angheloiu, George O; Rayarao, Geetha; Williams, Ronald; Yamrozik, June; Doyle, Mark; Biederman, Robert W W

2015-01-01

'Septal bounce' is a pathognomonic sign of constrictive pericarditis (CP). The objectives of the study are to resolve the etiology of the septal bounce, to generate septal bounce-related diagnostic tools, and to prove that its presence is related to the mechanical interaction between the atrioventricular inflow and the inter-ventricular septum. We compared steady state free precession four-chamber images between 11 CP patients and 11 controls via cardiac magnetic resonance. The septal bounce was composed of two movements observed during every cardiac cycle, simultaneous with the rapid filling and atrial systole respectively. Three parameters (measured at end-systole) were generated: right ventricular (RV) clamp (compression ratio of the RV)-greater in CP (0.88 ± 0.03) than controls (0.85 ± 0.03, p = 0.02), tri-septal angle between the tricuspid valve annulus plane and the interventricular septum (81° ± 9° vs. 91° ± 7°, p = 0.01), and impact angle between the tricuspid inflow vector and septum (8.6° ± 8.7° vs. 0° ± 6.6°, p = 0.01). The accuracy, positive predictive value, sensitivity and specificity of these parameters in differentiating CP from controls ranged from 100 to 82 %. A forth parameter-septal flow ratio, gauging the proportion of tricuspid inflow impacting the septum, was markedly higher in CP than controls (0.38 ± 0.19 vs. 0.01 ± 0.03, p < 0.0001) with 100 % sensitivity, specificity, positive and negative predictive value. The septal bounce consists of two sequential movements during each cardiac cycle, is time-related with the rapid ventricular filling and atrial systole, and likely represents a result of the tricuspid blood inflow impacting the interventricular septum. Four septal bounce-derived parameters have a good accuracy in differentiating CP from volunteers.

A robust two-node, 13 moment quadrature method of moments for dilute particle flows including wall bouncing

NASA Astrophysics Data System (ADS)

Sun, Dan; Garmory, Andrew; Page, Gary J.

2017-02-01

For flows where the particle number density is low and the Stokes number is relatively high, as found when sand or ice is ingested into aircraft gas turbine engines, streams of particles can cross each other's path or bounce from a solid surface without being influenced by inter-particle collisions. The aim of this work is to develop an Eulerian method to simulate these types of flow. To this end, a two-node quadrature-based moment method using 13 moments is proposed. In the proposed algorithm thirteen moments of particle velocity, including cross-moments of second order, are used to determine the weights and abscissas of the two nodes and to set up the association between the velocity components in each node. Previous Quadrature Method of Moments (QMOM) algorithms either use more than two nodes, leading to increased computational expense, or are shown here to give incorrect results under some circumstances. This method gives the computational efficiency advantages of only needing two particle phase velocity fields whilst ensuring that a correct combination of weights and abscissas is returned for any arbitrary combination of particle trajectories without the need for any further assumptions. Particle crossing and wall bouncing with arbitrary combinations of angles are demonstrated using the method in a two-dimensional scheme. The ability of the scheme to include the presence of drag from a carrier phase is also demonstrated, as is bouncing off surfaces with inelastic collisions. The method is also applied to the Taylor-Green vortex flow test case and is found to give results superior to the existing two-node QMOM method and is in good agreement with results from Lagrangian modelling of this case.

Breakthrough revisited: investigating the requirements for growth of dust beyond the bouncing barrier

NASA Astrophysics Data System (ADS)

Booth, Richard A.; Meru, Farzana; Lee, Man Hoi; Clarke, Cathie J.

2018-03-01

For grain growth to proceed effectively and lead to planet formation, a number of barriers to growth must be overcome. One such barrier, relevant for compact grains in the inner regions of the disc, is the `bouncing barrier' in which large grains (˜mm size) tend to bounce off each other rather than sticking. However, by maintaining a population of small grains, it has been suggested that cm-size particles may grow rapidly by sweeping up these small grains. We present the first numerically resolved investigation into the conditions under which grains may be lucky enough to grow beyond the bouncing barrier by a series of rare collisions leading to growth (so-called `breakthrough'). Our models support previous results, and show that in simple models breakthrough requires the mass ratio at which high-velocity collisions transition to growth instead of causing fragmentation to be low, ϕ ≲ 50. However, in models that take into account the dependence of the fragmentation threshold on mass ratio, we find that breakthrough occurs more readily, even if mass transfer is relatively inefficient. This suggests that bouncing may only slow down growth, rather than preventing growth beyond a threshold barrier. However, even when growth beyond the bouncing barrier is possible, radial drift will usually prevent growth to arbitrarily large sizes.

From black holes to white holes: a quantum gravitational, symmetric bounce

NASA Astrophysics Data System (ADS)

Olmedo, Javier; Saini, Sahil; Singh, Parampreet

2017-11-01

Recently, a consistent non-perturbative quantization of the Schwarzschild interior resulting in a bounce from black hole to white hole geometry has been obtained by loop quantizing the Kantowski-Sachs vacuum spacetime. As in other spacetimes where the singularity is dominated by the Weyl part of the spacetime curvature, the structure of the singularity is highly anisotropic in the Kantowski-Sachs vacuum spacetime. As a result, the bounce turns out to be in general asymmetric, creating a large mass difference between the parent black hole and the child white hole. In this manuscript, we investigate under what circumstances a symmetric bounce scenario can be constructed in the above quantization. Using the setting of Dirac observables and geometric clocks, we obtain a symmetric bounce condition which can be satisfied by a slight modification in the construction of loops over which holonomies are considered in the quantization procedure. These modifications can be viewed as quantization ambiguities, and are demonstrated in three different flavors, all of which lead to a non-singular black to white hole transition with identical masses. Our results show that quantization ambiguities can mitigate or even qualitatively change some key features of the physics of singularity resolution. Further, these results are potentially helpful in motivating and constructing symmetric black to white hole transition scenarios.

Symmetry breaking in drop bouncing on curved surfaces

PubMed Central

Liu, Yahua; Andrew, Matthew; Li, Jing; Yeomans, Julia M.; Wang, Zuankai

2015-01-01

The impact of liquid drops on solid surfaces is ubiquitous in nature, and of practical importance in many industrial processes. A drop hitting a flat surface retains a circular symmetry throughout the impact process. Here we show that a drop impinging on Echevaria leaves exhibits asymmetric bouncing dynamics with distinct spreading and retraction along two perpendicular directions. This is a direct consequence of the cylindrical leaves that have a convex/concave architecture of size comparable to the drop. Systematic experimental investigations on mimetic surfaces and lattice Boltzmann simulations reveal that this novel phenomenon results from an asymmetric momentum and mass distribution that allows for preferential fluid pumping around the drop rim. The asymmetry of the bouncing leads to ∼40% reduction in contact time. PMID:26602170

Memory in random bouncing ball dynamics

NASA Astrophysics Data System (ADS)

Zouabi, C.; Scheibert, J.; Perret-Liaudet, J.

2016-09-01

The bouncing of an inelastic ball on a vibrating plate is a popular model used in various fields, from granular gases to nanometer-sized mechanical contacts. For random plate motion, so far, the model has been studied using Poincaré maps in which the excitation by the plate at successive bounces is assumed to be a discrete Markovian (memoryless) process. Here, we investigate numerically the behaviour of the model for continuous random excitations with tunable correlation time. We show that the system dynamics are controlled by the ratio of the Markovian mean flight time of the ball and the mean time between successive peaks in the motion of the exciting plate. When this ratio, which depends on the bandwidth of the excitation signal, exceeds a certain value, the Markovian approach is appropriate; below, memory of preceding excitations arises, leading to a significant decrease of the jump duration; at the smallest values of the ratio, chattering occurs. Overall, our results open the way for uses of the model in the low-excitation regime, which is still poorly understood.

Influence of bouncing and assisted autogenic drainage on acid gastro-oesophageal reflux in infants.

PubMed

Van Ginderdeuren, Filip; Vandenplas, Yvan; Deneyer, Michel; Vanlaethem, Sylvie; Buyl, Ronald; Kerckhofs, Eric

2017-08-01

To determine the influence of modern airway clearance techniques using assisted autogenic drainage (AAD), whether or not combined with bouncing, on acid gastro-oesophageal reflux (GOR) in infants <1 year. In this controlled trial with intra-subject design infants were studied using oesophageal pH monitoring over 24 h, during which they received one 15 min session of bouncing, AAD or bouncing combined with AAD (BAAD). The number of reflux episodes (RE) and the refluxindex (RI) were the outcome measures. The results obtained during (T15) and 15 min after the intervention (T30) were compared to a period of 15 min before treatment (T0). The results of 150 infants, evenly distributed over the three treatment groups, were analyzed. No significant differences were found in number of RE at T15 and T30 compared to T0 in the bouncing group (P = 0.42), the AAD group (P = 0.14), and the BAAD group (P = 0.91). RI was significantly lower in the AAD group at T15 compared to T0 (P < 0.01). No differences in RI were found in the bouncing group (P = 0.28), nor in the BAAD group (P = 0.81). Bouncing, AAD and BAAD do not induce, nor aggravate acid GOR in infants under the age of 1 year. © 2017 Wiley Periodicals, Inc.

Small Business Innovation Research GRC Phase I, Phase II, and Post-Phase II Opportunity Assessment for 2015

NASA Technical Reports Server (NTRS)

Nguyen, Hung D.; Steele, Gynelle C.

2016-01-01

This report outlines the 2015 Small Business Innovation Research/Small Business Technology Transfer (SBIR/STTR) Phase I, Phase II, and Post-Phase II opportunity contract award results associated with NASA's Aeronautics Research Mission Directorate (ARMD), Human Exploration and Operations Mission Directorate (HEOMD), Science Mission Directorate (SMD), and Space Technology Mission Directorate (STMD) for NASA Glenn Research Center. The report also highlights the number of Phase I, Phase II, and Post-Phase II contracts awarded by mission directorate. The 2015 Phase I contract awards to companies in Ohio and their corresponding technologies are also discussed.

Non-stationary dynamics in the bouncing ball: A wavelet perspective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Behera, Abhinna K., E-mail: abhinna@iiserkol.ac.in; Panigrahi, Prasanta K., E-mail: pprasanta@iiserkol.ac.in; Sekar Iyengar, A. N., E-mail: ansekar.iyengar@saha.ac.in

2014-12-01

The non-stationary dynamics of a bouncing ball, comprising both periodic as well as chaotic behavior, is studied through wavelet transform. The multi-scale characterization of the time series displays clear signatures of self-similarity, complex scaling behavior, and periodicity. Self-similar behavior is quantified by the generalized Hurst exponent, obtained through both wavelet based multi-fractal detrended fluctuation analysis and Fourier methods. The scale dependent variable window size of the wavelets aptly captures both the transients and non-stationary periodic behavior, including the phase synchronization of different modes. The optimal time-frequency localization of the continuous Morlet wavelet is found to delineate the scales corresponding tomore » neutral turbulence, viscous dissipation regions, and different time varying periodic modulations.« less

People bouncing on trampolines: dramatic energy transfer, a table-top demonstration, complex dynamics and a zero sum game.

PubMed

Srinivasan, Manoj; Wang, Yang; Sheets, Alison

2013-01-01

Jumping on trampolines is a popular backyard recreation. In some trampoline games (e.g., "seat drop war"), when two people land on the trampoline with only a small time-lag, one person bounces much higher than the other, as if energy has been transferred from one to the other. First, we illustrate this energy-transfer in a table-top demonstration, consisting of two balls dropped onto a mini-trampoline, landing almost simultaneously, sometimes resulting in one ball bouncing much higher than the other. Next, using a simple mathematical model of two masses bouncing passively on a massless trampoline with no dissipation, we show that with specific landing conditions, it is possible to transfer all the kinetic energy of one mass to the other through the trampoline - in a single bounce. For human-like parameters, starting with equal energy, the energy transfer is maximal when one person lands approximately when the other is at the bottom of her bounce. The energy transfer persists even for very stiff surfaces. The energy-conservative mathematical model exhibits complex non-periodic long-term motions. To complement this passive bouncing model, we also performed a game-theoretic analysis, appropriate when both players are acting strategically to steal the other player's energy. We consider a zero-sum game in which each player's goal is to gain the other player's kinetic energy during a single bounce, by extending her leg during flight. For high initial energy and a symmetric situation, the best strategy for both subjects (minimax strategy and Nash equilibrium) is to use the shortest available leg length and not extend their legs. On the other hand, an asymmetry in initial heights allows the player with more energy to gain even more energy in the next bounce. Thus synchronous bouncing unstable is unstable both for passive bouncing and when leg lengths are controlled as in game-theoretic equilibria.

Electrostatic ``bounce'' instability in a magnetotail configuration

NASA Astrophysics Data System (ADS)

Fruit, G.; Louarn, P.; Tur, A.

2013-02-01

To understand the possible destabilization of two-dimensional current sheets, a kinetic model is proposed to describe the resonant interaction between electrostatic modes and trapped particles that bounce within the sheet. This work follows the initial investigation by Tur et al. [Phys. Plasmas 17, 102905 (2010)] that is revised and extended. Using a quasi-parabolic equilibrium state, the linearized gyro-kinetic Vlasov equation is solved for electrostatic fluctuations with period of the order of the electron bounce period. Using an appropriated Fourier expansion of the particle motion along the magnetic field, the complete time integration of the non-local perturbed distribution functions is performed. The dispersion relation for electrostatic modes is then obtained through the quasineutrality condition. It is found that strongly unstable electrostatic modes may develop provided that the current sheet is moderately stretched and, more important, that the proportion of passing particle remains small (less than typically 10%). This strong but finely tuned instability may offer opportunities to explain features of magnetospheric substorms.

BOUNCE: A community-based mother–daughter healthy lifestyle intervention for low-income Latino families

USDA-ARS?s Scientific Manuscript database

The primary purpose of this study was to assess the efficacy of a family-based exploratory community study titled BOUNCE (Behavior Opportunities Uniting Nutrition, Counseling, and Exercise), to increase physical fitness and activity in low-income Latino mothers and daughters. The BOUNCE study consis...

Ten Ways to Foster Resilience in Young Children--Teaching Kids to "Bounce Back"

ERIC Educational Resources Information Center

Petty, Karen

2014-01-01

Resilience has often been defined as the ability to bounce back in times of adversity and to develop in a positive way when faced with setbacks. Children routinely show high amounts of resilience mostly because of temperament and a built-in sense of autonomy.Children are able to overcome adversity to bounce back before social and emotional harm is…

Evidence for Bouncing Evolution Before Inflation After BICEP2

NASA Astrophysics Data System (ADS)

Xia, Jun-Qing; Cai, Yi-Fu; Li, Hong; Zhang, Xinmin

2014-06-01

The BICEP2 Collaboration reports a detection of primordial cosmic microwave background (CMB) B mode with a tensor-to-scalar ratio r =0.20-0.05+0.07 (68% C.L.). However, this result disagrees with the recent Planck limit r<0.11 (95% C.L.) on constraining inflation models. In this Letter we consider an inflationary cosmology with a preceding nonsingular bounce, which gives rise to observable signatures on primordial perturbations. One interesting phenomenon is that both the primordial scalar and tensor modes can have a step feature on their power spectra, which nicely cancels the tensor excess power on the CMB temperature power spectrum. By performing a global analysis, we obtain the 68% C.L. constraints on the parameters of the model from the Planck+WP and BICEP2 data together: the jump scale log10(kB/Mpc-1)=-2.4±0.2 and the spectrum amplitude ratio of bounce to inflation rB≡Pm/As=0.71±0.09. Our result reveals that the bounce inflation scenario can simultaneously explain the Planck and BICEP2 observations better than the standard cold dark matter model with a cosmological constant, and can be verified by future CMB polarization measurements.

29 CFR 801.25 - Rights of examinee-post-test phase.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 29 Labor 3 2014-07-01 2014-07-01 false Rights of examinee-post-test phase. 801.25 Section 801.25... § 801.25 Rights of examinee—post-test phase. (a) The post-test phase refers to any questioning or other... of the test with the examinee. Before any adverse employment action, the employer must: (1) Further...

29 CFR 801.25 - Rights of examinee-post-test phase.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 3 2011-07-01 2011-07-01 false Rights of examinee-post-test phase. 801.25 Section 801.25... § 801.25 Rights of examinee—post-test phase. (a) The post-test phase refers to any questioning or other... of the test with the examinee. Before any adverse employment action, the employer must: (1) Further...

29 CFR 801.25 - Rights of examinee-post-test phase.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Rights of examinee-post-test phase. 801.25 Section 801.25... § 801.25 Rights of examinee—post-test phase. (a) The post-test phase refers to any questioning or other... of the test with the examinee. Before any adverse employment action, the employer must: (1) Further...

29 CFR 801.25 - Rights of examinee-post-test phase.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 29 Labor 3 2012-07-01 2012-07-01 false Rights of examinee-post-test phase. 801.25 Section 801.25... § 801.25 Rights of examinee—post-test phase. (a) The post-test phase refers to any questioning or other... of the test with the examinee. Before any adverse employment action, the employer must: (1) Further...

29 CFR 801.25 - Rights of examinee-post-test phase.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 29 Labor 3 2013-07-01 2013-07-01 false Rights of examinee-post-test phase. 801.25 Section 801.25... § 801.25 Rights of examinee—post-test phase. (a) The post-test phase refers to any questioning or other... of the test with the examinee. Before any adverse employment action, the employer must: (1) Further...

Cosmological singularities and bounce in Cartan-Einstein theory

NASA Astrophysics Data System (ADS)

Lucat, Stefano; Prokopec, Tomislav

2017-10-01

We consider a generalized Einstein-Cartan theory, in which we add the unique covariant dimension four operators to general relativity that couples fermionic spin current to the torsion tensor (with an arbitrary strength). Since torsion is local and non-dynamical, when integrated out it yields an effective four-fermion interaction of the gravitational strength. We show how to renormalize the theory, in the one-loop perturbative expansion in generally curved space-times, obtaining the first order correction to the 2PI effective action in Schwinger-Keldysh (in-in) formalism. We then apply the renormalized theory to study the dynamics of a collapsing universe that begins in a thermal state and find that—instead of a big crunch singularity—the Universe with torsion undergoes a bounce. We solve the dynamical equations (a) classically (without particle production); (b) including the production of fermions in a fixed background in the Hartree-Fock approximation and (c) including the quantum backreaction of fermions onto the background space-time. In the first and last cases the Universe undergoes a bounce. The production of fermions due to the coupling to a contracting homogeneous background speeds up the bounce, implying that the quantum contributions from fermions is negative, presumably because fermion production contributes negatively to the energy-momentum tensor. When compared with former works on the subject, our treatment is fully microscopic (namely, we treat fermions by solving the corresponding Dirac equations) and quantum (in the sense that we include fermionic loop contributions).

Bouncing on Mars and the Moon-the role of gravity on neuromuscular control: correlation of muscle activity and rate of force development.

PubMed

Ritzmann, Ramona; Freyler, Kathrin; Krause, Anne; Gollhofer, Albert

2016-11-01

On our astronomical neighbors Mars and the Moon, bouncing movements are the preferred locomotor techniques. During bouncing, the stretch-shortening cycle describes the muscular activation pattern. This study aimed to identify gravity-dependent changes in kinematic and neuromuscular characteristics in the stretch-shortening cycle. Hence, neuromuscular control of limb muscles as well as correlations between the muscles' pre-activation, reflex components, and force output were assessed in lunar, Martian, and Earth gravity. During parabolic flights, peak force (F max ), ground-contact-time, rate of force development (RFD), height, and impulse were measured. Electromyographic (EMG) activities in the m. soleus (SOL) and gastrocnemius medialis (GM) were assessed before (PRE) and during bounces for the reflex phases short-, medium-, and long-latency response (SLR, MLR, LLR). With gradually decreasing gravitation, F max , RFD, and impulse were reduced, whereas ground-contact time and height increased. Concomitantly, EMG_GM decreased for PRE, SLR, MLR, and LLR, and in EMG_SOL in SLR, MLR, and LLR. For SLR and MLR, F max and RFD were positively correlated to EMG_SOL. For PRE and LLR, RFD and F max were positively correlated to EMG_GM. Findings emphasize that biomechanically relevant kinematic adaptations in response to gravity variation were accompanied by muscle- and phase-specific modulations in neural control. Gravitational variation is anticipated and compensated for by gravity-adjusted muscle activities. Importantly, the pre-activation and reflex phases were differently affected: in SLR and MLR, SOL is assumed to contribute to the decline in force output with a decreasing load, and, complementary in PRE and LLR, GM seems to be of major importance for force generation. Copyright © 2016 the American Physiological Society.

Measuring the rebound resilience of a bouncing ball

NASA Astrophysics Data System (ADS)

Wadhwa, Ajay

2012-09-01

Some balls which are made of high-quality rubber (an elastomeric) material, such as tennis or squash balls, could be used for the determination of an important property of such materials called resilience. Since a bouncing ball involves a single impact we call this property 'rebound resilience' and express it as the ratio of the rebound height to the initial drop height of the ball. We determine the rebound resilience for three different types of ball by calculating the coefficient of restitution of the ball-surface combination from the experimentally measurable physical quantities, such as initial drop height and time interval between successive bounces. Using these we also determine the contact time of balls with the surface of impact. For measurements we have used audio, motion and surface-temperature sensors that were interfaced through a USB port with a computer.

Prostate-Specific Antigen (PSA) Bounce After Dose-Escalated External Beam Radiation Therapy Is an Independent Predictor of PSA Recurrence, Metastasis, and Survival in Prostate Adenocarcinoma Patients.

PubMed

Romesser, Paul B; Pei, Xin; Shi, Weiji; Zhang, Zhigang; Kollmeier, Marisa; McBride, Sean M; Zelefsky, Michael J

2018-01-01

To evaluate the difference in prostate-specific antigen (PSA) recurrence-free, distant metastasis-free, overall, and cancer-specific survival between PSA bounce (PSA-B) and non-bounce patients treated with dose-escalated external beam radiation therapy (DE-EBRT). During 1990-2010, 1898 prostate adenocarcinoma patients were treated with DE-EBRT to ≥75 Gy with ≥5 years follow-up. Patients receiving neoadjuvant/concurrent androgen-deprivation therapy (n=1035) or with fewer than 4 PSA values obtained 6 months or more after post-EBRT completion (n=87) were excluded. The evaluable 776 patients were treated (median, 81.0 Gy). Prostate-specific antigen bounce was defined as a ≥0.2-ng/mL increase above the interval PSA nadir, followed by a decrease to nadir or below. Prostate-specific antigen relapse was defined as post-radiation therapy PSA nadir + 2 ng/mL. Median follow-up was 9.2 years (interquartile range, 6.9-11.3 years). One hundred twenty-three patients (15.9%) experienced PSA-B after DE-EBRT at a median of 24.6 months (interquartile range, 16.1-38.5 months). On multivariate analysis, younger age (P=.001), lower Gleason score (P=.0003), and higher radiation therapy dose (P=.0002) independently predicted PSA-B. Prostate-specific antigen bounce was independently associated with decreased risk for PSA relapse (hazard ratio [HR] 0.53; 95% confidence interval [CI] 0.33-0.85; P=.008), distant metastatic disease (HR 0.34; 95% CI 0.12-0.94; P=.04), and all-cause mortality (HR 0.53; 95% CI 0.29-0.96; P=.04) on multivariate Cox analysis. Because all 50 prostate cancer-specific deaths in patients without PSA-B were in the non-bounce cohort, competing-risks analysis was not applicable. A nonparametric competing-risks test demonstrated that patients with PSA-B had superior cancer-specific survival compared with patients without PSA-B (P=.004). Patients treated with dose-escalated radiation therapy for prostate adenocarcinoma who experience posttreatment PSA-B have

People Bouncing on Trampolines: Dramatic Energy Transfer, a Table-Top Demonstration, Complex Dynamics and a Zero Sum Game

PubMed Central

Srinivasan, Manoj; Wang, Yang; Sheets, Alison

2013-01-01

Jumping on trampolines is a popular backyard recreation. In some trampoline games (e.g., “seat drop war”), when two people land on the trampoline with only a small time-lag, one person bounces much higher than the other, as if energy has been transferred from one to the other. First, we illustrate this energy-transfer in a table-top demonstration, consisting of two balls dropped onto a mini-trampoline, landing almost simultaneously, sometimes resulting in one ball bouncing much higher than the other. Next, using a simple mathematical model of two masses bouncing passively on a massless trampoline with no dissipation, we show that with specific landing conditions, it is possible to transfer all the kinetic energy of one mass to the other through the trampoline – in a single bounce. For human-like parameters, starting with equal energy, the energy transfer is maximal when one person lands approximately when the other is at the bottom of her bounce. The energy transfer persists even for very stiff surfaces. The energy-conservative mathematical model exhibits complex non-periodic long-term motions. To complement this passive bouncing model, we also performed a game-theoretic analysis, appropriate when both players are acting strategically to steal the other player's energy. We consider a zero-sum game in which each player's goal is to gain the other player's kinetic energy during a single bounce, by extending her leg during flight. For high initial energy and a symmetric situation, the best strategy for both subjects (minimax strategy and Nash equilibrium) is to use the shortest available leg length and not extend their legs. On the other hand, an asymmetry in initial heights allows the player with more energy to gain even more energy in the next bounce. Thus synchronous bouncing unstable is unstable both for passive bouncing and when leg lengths are controlled as in game-theoretic equilibria. PMID:24236029

Conservation importance of early post-disturbance temperate forests

Treesearch

Charles Kwit; David I. King; Beverly Collins; Mark E. Swanson

2014-01-01

The early post-disturbance stage of temperate forest succession (also referred to as 'early-seral' or 'early-successional' forest) has been the subject of interest and debate. Often thought of as an ephemeral (and often disorganized) state of eventual closed-canopy systems, its direct and immediate role in conservation traditionally has been ignored...

Bouncing ball problem: stability of the periodic modes.

PubMed

Barroso, Joaquim J; Carneiro, Marcus V; Macau, Elbert E N

2009-02-01

Exploring all its ramifications, we give an overview of the simple yet fundamental bouncing ball problem, which consists of a ball bouncing vertically on a sinusoidally vibrating table under the action of gravity. The dynamics is modeled on the basis of a discrete map of difference equations, which numerically solved fully reveals a rich variety of nonlinear behaviors, encompassing irregular nonperiodic orbits, subharmonic and chaotic motions, chattering mechanisms, and also unbounded nonperiodic orbits. For periodic motions, the corresponding conditions for stability and bifurcation are determined from analytical considerations of a reduced map. Through numerical examples, it is shown that a slight change in the initial conditions makes the ball motion switch from periodic to chaotic orbits bounded by a velocity strip v=+/-Gamma(1-epsilon) , where Gamma is the nondimensionalized shaking acceleration and epsilon the coefficient of restitution which quantifies the amount of energy lost in the ball-table collision.

Doppler ultrasound surveillance in deep tunneling compressed-air work with Trimix breathing: bounce dive technique compared to saturation-excursion technique.

PubMed

Vellinga, T P van Rees; Sterk, W; de Boer, A G E M; van der Beek, A J; Verhoeven, A C; van Dijk, F J H

2008-01-01

The Western Scheldt Tunneling Project in The Netherlands provided a unique opportunity to evaluate two deep-diving techniques with Doppler ultrasound surveillance. Divers used the bounce diving techniques for repair and maintenance of the TBM. The tunnel boring machine jammed at its deepest depth. As a result the work time was not sufficient. The saturation diving technique was developed and permitted longer work time at great depth. Thirty-one divers were involved in this project. Twenty-three divers were examined using Doppler ultrasound. Data analysis addressed 52 exposures to Trimix at 4.6-4.8 bar gauge using the bounce technique and 354 exposures to Trimix at 4.0-6.9 bar gauge on saturation excursions. No decompression incidents occurred with either technique during the described phase of the project. Doppler ultrasound revealed that the bubble loads assessed in both techniques were generally low. We find out, that despite longer working hours, shorter decompression times and larger physical workloads, the saturation-excursion technique was associated with significant lower bubble grades than in the bounce technique using Doppler Ultrasound. We conclude that the saturation-excursion technique with Trimix is a good option for deep and long exposures in caisson work. The Doppler technique proved valuable, and it should be incorporated in future compressed-air work.

Cosmological singularities and bounce in Cartan-Einstein theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lucat, Stefano; Prokopec, Tomislav, E-mail: s.lucat@students.uu.nl, E-mail: t.prokopec@uu.nl

We consider a generalized Einstein-Cartan theory, in which we add the unique covariant dimension four operators to general relativity that couples fermionic spin current to the torsion tensor (with an arbitrary strength). Since torsion is local and non-dynamical, when integrated out it yields an effective four-fermion interaction of the gravitational strength. We show how to renormalize the theory, in the one-loop perturbative expansion in generally curved space-times, obtaining the first order correction to the 2PI effective action in Schwinger-Keldysh ( in-in ) formalism. We then apply the renormalized theory to study the dynamics of a collapsing universe that begins inmore » a thermal state and find that—instead of a big crunch singularity—the Universe with torsion undergoes a bounce . We solve the dynamical equations (a) classically (without particle production); (b) including the production of fermions in a fixed background in the Hartree-Fock approximation and (c) including the quantum backreaction of fermions onto the background space-time. In the first and last cases the Universe undergoes a bounce. The production of fermions due to the coupling to a contracting homogeneous background speeds up the bounce, implying that the quantum contributions from fermions is negative, presumably because fermion production contributes negatively to the energy-momentum tensor. When compared with former works on the subject, our treatment is fully microscopic (namely, we treat fermions by solving the corresponding Dirac equations) and quantum (in the sense that we include fermionic loop contributions).« less

Music therapy for early cognitive rehabilitation post-childhood TBI: an intrinsic mixed methods case study.

PubMed

Bower, Janeen; Catroppa, Cathy; Grocke, Denise; Shoemark, Helen

2014-10-01

The primary aim of this case study was to explore the behavioural changes of a paediatric patient in post-traumatic amnesia (PTA) during a music therapy session. A secondary objective was to measure the effect of the music therapy intervention on agitation. Video data from pre, during and post-music therapy sessions were collected and analysed using video micro-analysis and the Agitated Behaviour Scale. The participant displayed four discrete categories of behaviours: Neutral, Acceptance, Recruitment and Rejection. Further analysis revealed brief but consistent and repeated periods of awareness and responsiveness to the live singing of familiar songs, which were classified as Islands of Awareness. Song offered an Environment of Potential to maximise these periods of emerging consciousness. The quantitative data analysis yielded inconclusive results in determining if music therapy was effective in reducing agitation during and immediately post the music therapy sessions. The process of micro-analysis illuminated four discrete participant behaviours not apparent in the immediate clinical setting. The results of this case suggest that the use of familiar song as a music therapy intervention may harness early patient responsiveness to foster cognitive rehabilitation in the early acute phase post-TBI.

Phase III of Early Restoration | NOAA Gulf Spill Restoration

Science.gov Websites

information about this phase of Early Restoration, including fact sheets on each project. The final Phase III 44 projects are documented in a final Record of Decision. Information about Phase III of Early Archive Home Phase III of Early Restoration Phase III of Early Restoration Beach habitat would be restored

Bouncing cosmologies from quantum gravity condensates

NASA Astrophysics Data System (ADS)

Oriti, Daniele; Sindoni, Lorenzo; Wilson-Ewing, Edward

2017-02-01

We show how the large-scale cosmological dynamics can be obtained from the hydrodynamics of isotropic group field theory condensate states in the Gross-Pitaevskii approximation. The correct Friedmann equations are recovered in the classical limit for some choices of the parameters in the action for the group field theory, and quantum gravity corrections arise in the high-curvature regime causing a bounce which generically resolves the big-bang and big-crunch singularities.

Early post-operative cerebrospinal fluid hypovolemia: Report of 7 cases.

PubMed

Hou, Kun; Zhu, Xiaobo; Zhang, Yang; Gao, Xianfeng; Suo, Shihuan; Zhao, Jinchuan; Li, Guichen

2018-06-01

Cerebrospinal fluid (CSF) hypovolemia is a common neurosurgical condition, which may be spontaneous or iatrogenic. At our institution, a substantial number of the reported cases of early post-operative CSF hypovolemia were identified to have unintentional or unrecognized post-operative continuous excessive CSF leakage. Cases who presented with post-operative CSF hypovolemia several days after uneventful intracranial surgeries without continuous CSF leakage were rarely reported. A retrospective review of the medical records of these patients was performed to identify those patients who developed early post-operative CSF hypovolemia without the presence of post-operative continuous CSF leakage. A total of 7 patients, 5 of which were males, were identified in this retrospective study. They experienced CSF hypovolemia between days 1 and 7 after emergency or scheduled intracranial surgeries. Ventricular collapse, cisternal effacement and midline shift are the most common radiological observations. With early diagnosis and management, 4 of the patients achieved a Glasgow Outcome Scale (GOS) score of 5, 1 achieved a GOS score of 4 and the remaining 2 had a GOS score of 3. No mortality was noted in this series. Although rare in incidence, early post-operative CSF hypovolemia may occur without the existence of post-operative continuous CSF leakage. When the diagnosis of CSF hypovolemia is reached, factors that may exacerbate CSF compensation should be promptly terminated. Trendelenburg position and sufficient intravenous hydration are practical and effective managements, and CSF hypovolemia may thereby be reversed in a substantial number of patients.

The Larger the Viscosity, the Higher the Bounce

NASA Astrophysics Data System (ADS)

Stern, Menachem; Klein Schaarsberg, Martin; Peters, Ivo; Dodge, Kevin; Zhang, Wendy; Jaeger, Heinrich

A low-viscosity liquid drop can bounce upon impact onto a solid. A high-viscosity drop typically just flattens, i.e., it splats. Surprisingly, our experiments with a droplet made of densely packed glass beads in silicone oil display the opposite behavior: the low-viscosity oil suspension drop splats. The high-viscosity oil suspension bounces. Increasing solvent viscosity increases the rebound energy. To gain insight into the underlying mechanism, we model the suspension as densely packed elastic spheres experiencing viscous lubrication drag between neighbors. The model reproduces the observed trends. Plots of elastic compression and drag experienced by the particles show that rebounds are made possible by (1) a fraction of the impact energy being stored during initial contact via elastic compression, (2) a rapid broadening of local lubrication drag interactions at the initial impact site into a spatially uniform upward force throughout the drop. Including finite wall drag due to the presence of ambient air into the numerical model diminishes and eventually cuts off the rebound.

Low-sensitivity, low-bounce, high-linearity current-controlled oscillator suitable for single-supply mixed-mode instrumentation system.

PubMed

Hwang, Yuh-Shyan; Kung, Che-Min; Lin, Ho-Cheng; Chen, Jiann-Jong

2009-02-01

A low-sensitivity, low-bounce, high-linearity current-controlled oscillator (CCO) suitable for a single-supply mixed-mode instrumentation system is designed and proposed in this paper. The designed CCO can be operated at low voltage (2 V). The power bounce and ground bounce generated by this CCO is less than 7 mVpp when the power-line parasitic inductance is increased to 100 nH to demonstrate the effect of power bounce and ground bounce. The power supply noise caused by the proposed CCO is less than 0.35% in reference to the 2 V supply voltage. The average conversion ratio KCCO is equal to 123.5 GHz/A. The linearity of conversion ratio is high and its tolerance is within +/-1.2%. The sensitivity of the proposed CCO is nearly independent of the power supply voltage, which is less than a conventional current-starved oscillator. The performance of the proposed CCO has been compared with the current-starved oscillator. It is shown that the proposed CCO is suitable for single-supply mixed-mode instrumentation systems.

Possible evolution of a bouncing universe in cosmological models with non-minimally coupled scalar fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pozdeeva, Ekaterina O.; Vernov, Sergey Yu.; Skugoreva, Maria A.

2016-12-01

We explore dynamics of cosmological models with bounce solutions evolving on a spatially flat Friedmann-Lemaître-Robertson-Walker background. We consider cosmological models that contain the Hilbert-Einstein curvature term, the induced gravity term with a negative coupled constant, and even polynomial potentials of the scalar field. Bounce solutions with non-monotonic Hubble parameters have been obtained and analyzed. The case when the scalar field has the conformal coupling and the Higgs-like potential with an opposite sign is studied in detail. In this model the evolution of the Hubble parameter of the bounce solution essentially depends on the sign of the cosmological constant.

Bouncing and coalescence of droplets on falling liquid films

NASA Astrophysics Data System (ADS)

Che, Zhizhao; Deygas, Amandine; Matar, Omar

2014-11-01

When a droplet impacts on a falling liquid film, the outcome depends on the fluid properties of the droplet, its speed, and angle of incidence, as well as on the film flow rate and associated flow regimes. In this study, the oblique impact of droplets on a falling liquid film is investigated experimentally. The falling film is created on an inclined substrate and the Reynolds number is varied. Droplets with different sizes and different speeds are used to study the impact process for different Weber and Ohnesorge numbers. Different phenomena of droplet impact are identified and analysed, such as bouncing, partial coalescence, total coalescence, and splashing. An impact regime map is generated, and the effects of droplet impact speed and size, and the film flow rates are studied. The propagation of waves on the liquid film post-impact is analysed. The results show that the flowing film can significantly affect the impact process of droplets, and the latter can alter the propagation of waves on the falling film. EPSRC Programme Grant, MEMPHIS, EP/K0039761/1.

Early-phase prandial insulin secretion: its role in the pathogenesis of type 2 diabetes mellitus and its modulation by repaglinide.

PubMed

Owens, D R; Cozma, L S; Luzio, S D

2002-12-01

The major contributory factor to increasing hyperglycaemia in established Type 2 diabetes mellitus (T2DM) appears to be the progressive delay and attenuation of the prandial insulin response. An important consequence of this derangement is that hepatic glucose production is no longer suppressed during times of prandial glucose intake. Together with a relative impairment in the rate of peripheral glucose disposal, this leads to supra-physiological plasma glucose excursions, which may damage the vasculature. An obvious therapeutic strategy, therefore, would be to increase insulin availability when most needed--in the early prandial phase. In experiments with exogenous insulin interventions, peak post-prandial blood glucose increments were curtailed without undue increases in total insulin exposure. However, available evidence suggests that the sulphonylurea glibenclamide does not effectively alter early-phase prandial insulin release but predominately increases late-phase and basal insulin output, thus incurring the risk of hypoglycaemia. The novel insulin secretagogue repaglinide, by contrast, augments early-phase prandial insulin secretion when taken before meals, as shown by studies in non-diabetic people and patients with newly diagnosed, previously untreated T2DM. Repaglinide exerts its greatest effect on the insulin secretion rate during the first 30 min after a meal is started, thereby going some way to restoring the early insulin secretion curve seen after a meal in non-diabetic people. No residual secretagogue activity is seen 4 hr after taking a single dose of up to 2 mg. Prandial glucose regulation with repaglinide could be associated with lower post-prandial glucose excursions and less risk of post-prandial hypoglycaemia than glibenclamide.

Early-Phase 11C-PiB PET in Amyloid Angiopathy-Related Symptomatic Cerebral Hemorrhage: Potential Diagnostic Value?

PubMed Central

Aigbirhio, Franklin I.; Fryer, Tim D.; Menon, David K.; Warburton, Elizabeth A.; Baron, Jean-Claude

2015-01-01

Although late-phase (>35min post-administration) 11C-PiB-PET has good sensitivity in cerebral amyloid angiopathy (CAA), its specificity is poor due to frequently high uptake in healthy aged subjects. By detecting perfusion-like abnormalities, early-phase 11C-PiB-PET might add diagnostic value. Early-frame (1–6min) 11C-PiB-PET was obtained in 11 non-demented patients with probable CAA-related symptomatic lobar intracerebral haemorrhage (70±7yrs), 9 age-matched healthy controls (HCs) and 10 HCs <55yrs. There was a significant decrease in early-phase atrophy-corrected whole-cortex SUV relative to cerebellar vermis (SUVR) in the CAA vs age-matched HC group. None of the age-matched controls fell below the lower 95% confidence limit derived from the young HCs, while 6/11 CAA patients did (sensitivity = 55%, specificity = 100%). Combining both early- and late-phase 11C-PiB data did not change the sensitivity and specificity of late-phase PiB, but combined early- and late-phase positivity entails a very high suspicion of underlying Aβ-related clinical disorder, i.e., CAA or Alzheimer disease (AD). In order to clarify this ambiguity, we then show that the occipital/posterior cingulate ratio is markedly lower in CAA than in AD (N = 7). These pilot data suggest that early-phase 11C-PiB-PET may not only add to late-phase PiB-PET with respect to the unclear situation of late-phase positivity, but also help differentiate CAA from AD. PMID:26439113

Thump, Ring: The Sound of a Bouncing Ball

ERIC Educational Resources Information Center

Katz, J. I.

2010-01-01

A basketball bounced on a stiff surface produces a characteristic loud thump, followed by a high-pitched ringing. Describing the ball as an inextensible but flexible membrane containing compressed air, I formulate an approximate theory of the generation of these sounds and predict their amplitudes and waveforms. (Contains 3 figures.)

BOUNCE: An exploratory healthy lifestyle summer intervention for girls

USDA-ARS?s Scientific Manuscript database

Our objective was to assess the efficacy of the Behavior Opportunities Uniting Nutrition Counseling (BOUNCE) parent-daughter intervention in promoting selected physical fitness measures and activity. Thirty-seven Latino and African American parent-daughter pairs participated in the study. The interv...

Variable reluctance switch avoids contact corrosion and contact bounce

NASA Technical Reports Server (NTRS)

Watson, P. C.

1967-01-01

Variable reluctance switch avoids contact corrosion and bounce in a hostile environment. It consists of a wire-wound magnetic core and moveable bridge piece that alters the core flux pattern to produce an electrical output useful for switching control media.

Microcrystallography using single-bounce monocapillary optics

PubMed Central

Gillilan, R. E.; Cook, M. J.; Cornaby, S. W.; Bilderback, D. H.

2010-01-01

X-ray microbeams have become increasingly valuable in protein crystallography. A number of synchrotron beamlines worldwide have adapted to handling smaller and more challenging samples by providing a combination of high-precision sample-positioning hardware, special visible-light optics for sample visualization, and small-diameter X-ray beams with low background scatter. Most commonly, X-ray microbeams with diameters ranging from 50 µm to 1 µm are produced by Kirkpatrick and Baez mirrors in combination with defining apertures and scatter guards. A simple alternative based on single-bounce glass monocapillary X-ray optics is presented. The basic capillary design considerations are discussed and a practical and robust implementation that capitalizes on existing beamline hardware is presented. A design for mounting the capillary is presented which eliminates parasitic scattering and reduces deformations of the optic to a degree suitable for use on next-generation X-ray sources. Comparison of diffraction data statistics for microcrystals using microbeam and conventional aperture-collimated beam shows that capillary-focused beam can deliver significant improvement. Statistics also confirm that the annular beam profile produced by the capillary optic does not impact data quality in an observable way. Examples are given of new structures recently solved using this technology. Single-bounce monocapillary optics can offer an attractive alternative for retrofitting existing beamlines for microcrystallography. PMID:20157276

Spontaneous Droplet Jump with Electro-Bouncing

NASA Astrophysics Data System (ADS)

Schmidt, Erin; Weislogel, Mark

2016-11-01

We investigate the dynamics of water droplet jumps from superhydrophobic surfaces in the presence of an electric field during a step reduction in gravity level. In the brief free-fall environment of a drop tower, when a strong non-homogeneous electric field (with a measured strength between 0 . 39 and 2 . 36 kV/cm) is imposed, body forces acting on the jumped droplets are primarily supplied by polarization stress and Coulombic attraction instead of gravity. The droplet charge, measured to be on the order of 2 . 3 . (10-11) C, originates by electro-osmosis of charged species at the (PTFE coated) hydrophobic surface interface. This electric body force leads to a droplet bouncing behavior similar to well-known phenomena in 1-g, though occurring for larger drops 0.1 mL for a given range of impact Weber numbers, We < 20 . In 1-g, for We > 0 . 4 , impact recoil behavior on a super-hydrophobic surface is normally dominated by damping from contact line hysteresis and by air-layer interactions. However, in the strong electric field, the droplet bounce dynamics additionally include electrohydrodynamic effects on wettability and Cassie-Wenzel transition. This is qualitatively discussed in terms of coefficients of restitution and trends in contact time. This work was supported primarily by NASA Cooperative Agreement NNX12A047A.

Experimental observation of electron bounce resonance through electron energy distribution measurement in a finite size inductively coupled plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gu, Seuli; Kang, Hyun-Ju; Kim, Yu-Sin

2016-06-15

The electron bounce resonance was experimentally investigated in a low pressure planar inductively coupled plasma. The electron energy probability functions (EEPFs) were measured at different chamber heights and the energy diffusion coefficients were calculated by the kinetic model. It is found that the EEPFs begin to flatten at the first electron bounce resonance condition, and the plateau shifts to a higher electron energy as the chamber height increases. The plateau which indicates strong electron heating corresponds not only to the electron bounce resonance condition but also to the peaks of the first component of the energy diffusion coefficients. As amore » result, the plateau formation in the EEPFs is mainly due to the electron bounce resonance in a finite inductive discharge.« less

Antigravity treadmill training during the early rehabilitation phase following unicompartmental knee arthroplasty: A case series.

PubMed

Huang, Chun-Hao; Schroeder, E Todd; Powers, Christopher

2018-02-26

Patients who have undergone unicompartmental knee arthroplasty (UKA) have been reported to exhibit altered gait 19-25 months post-surgery. The most common gait impairment in this population is inadequate knee flexion and a corresponding decrease in the knee extensor moment during loading response (i.e., quadriceps avoidance). The purpose of this case series was to determine whether incorporation of antigravity treadmill training into a standard physical therapy program can eliminate quadriceps avoidance gait during the early rehabilitation phase following UKA. Four females who underwent UKA were recruited for this study. Participants completed antigravity treadmill training three times per week for 12 weeks in addition to their standard physical therapy program. Instrumented gait analysis was performed at baseline (pre-intervention), week 6 (mid-intervention), and week 12 (post-intervention). We found that peak knee flexion and the peak knee extensor moment during the weight acceptance phase of gait increased to normal values following the 12-week intervention period (14.1 ± 6.5° to 20.6 ± 1.5° and 0.4 ± 0.3 to 0.7 ± 0.2 Nm/kg respectively). The findings of this case series suggest that a standard physical therapy program that incorporates early gait training using an antigravity treadmill may be beneficial in eliminating "quadriceps avoidance" during the early rehabilitation phase following UKA.

Phase V of Early Restoration | NOAA Gulf Spill Restoration

Science.gov Websites

Phase V Early Restoration Plan and Environmental Assessment. The project will acquire land along Florida million. Phase V Early Restoration Plan and Environmental Assessment (pdf, 10 MB) Draft Phase V Early Restoration Plan and Environmental Assessment (Executive Summary) (2 MB) Phase V Fact Sheet (pdf, 2 MB) Gulf

Keeping the Beat: A Large Sample Study of Bouncing and Clapping to Music

PubMed Central

Tranchant, Pauline; Vuvan, Dominique T.; Peretz, Isabelle

2016-01-01

The vast majority of humans move in time with a musical beat. This behaviour has been mostly studied through finger-tapping synchronization. Here, we evaluate naturalistic synchronization responses to music–bouncing and clapping–in 100 university students. Their ability to match the period of their bounces and claps to those of a metronome and musical clips varying in beat saliency was assessed. In general, clapping was better synchronized with the beat than bouncing, suggesting that the choice of a specific movement type is an important factor to consider in the study of sensorimotor synchronization processes. Performance improved as a function of beat saliency, indicating that beat abstraction plays a significant role in synchronization. Fourteen percent of the population exhibited marked difficulties with matching the beat. Yet, at a group level, poor synchronizers showed similar sensitivity to movement type and beat saliency as normal synchronizers. These results suggest the presence of quantitative rather than qualitative variations when losing the beat. PMID:27471854

Why Low Bounce Balls Exhibit High Rolling Resistance

ERIC Educational Resources Information Center

Cross, Rod

2015-01-01

A simple experiment is described to measure the coefficient of rolling friction for a low bounce ball rolling on a horizontal surface. As observed previously by others, the coefficient increased with rolling speed. The energy loss due to rolling friction can be explained in terms of the measured coefficient of restitution for the ball, meaning…

Measuring the Rebound Resilience of a Bouncing Ball

ERIC Educational Resources Information Center

Wadhwa, Ajay

2012-01-01

Some balls which are made of high-quality rubber (an elastomeric) material, such as tennis or squash balls, could be used for the determination of an important property of such materials called resilience. Since a bouncing ball involves a single impact we call this property "rebound resilience" and express it as the ratio of the rebound height to…

Van Allen Probes observations of drift-bounce resonance and energy transfer between energetic ring current protons and poloidal Pc4 wave

NASA Astrophysics Data System (ADS)

Oimatsu, S.; Masahito, N.; Takahashi, K.; Yamamoto, K.; Keika, K.; Kletzing, C.; MacDowall, R. J.; Smith, C.; Mitchell, D. G.

2017-12-01

Poloidal Pc4 wave and proton flux oscillation due to the drift-bounce resonance are observed in the inner magnetosphere on the dayside near the magnetic equator by the Van Allen Probes spacecraft on 2 March 2014. The flux modulation is observed in the energy range of 67.0 keV to 268.8 keV with the same frequency of poloidal Pc4 wave. We estimate the resonant energy to be 120 keV for pitch angle (α) of 20º-40º or 140º-160º, and 170-180 keV for α=40º-60º or 120º-140º. The drift-bounce resonance theory gives the resonant energy of 110-120 keV, which is consistent with the observation for small α (or large α when α≥90º), but slightly higher than the observation for large α (or small α when α≥90º). We consider that this discrepancy of the resonant energy is due to the drift shell splitting. In order to examine the direction of energy flow between protons and the wave, we calculate the sign of the gradient of proton phase space density (df/dW) in both outbound and inbound paths. Results showed positive gradient in both paths, which means that the energy is transferred from the protons to the wave. During the appearance of poloidal Pc4 wave, the Dst* index shows a sudden increase of 6.7 nT. We estimate the total energy loss of the ring current from the recovery of the Dst* index and the variation of proton flux by the drift-bounce resonance. The estimated energy loss is almost comparable for both cases. Therefore, we suggest that the energy transfer from the ring current protons to the wave via the drift-bounce resonance cause the increase of Dst* index.

Optimal control of a hybrid rhythmic-discrete task: the bouncing ball revisited.

PubMed

Ronsse, Renaud; Wei, Kunlin; Sternad, Dagmar

2010-05-01

Rhythmically bouncing a ball with a racket is a hybrid task that combines continuous rhythmic actuation of the racket with the control of discrete impact events between racket and ball. This study presents experimental data and a two-layered modeling framework that explicitly addresses the hybrid nature of control: a first discrete layer calculates the state to reach at impact and the second continuous layer smoothly drives the racket to this desired state, based on optimality principles. The testbed for this hybrid model is task performance at a range of increasingly slower tempos. When slowing the rhythm of the bouncing actions, the continuous cycles become separated into a sequence of discrete movements interspersed by dwell times and directed to achieve the desired impact. Analyses of human performance show increasing variability of performance measures with slower tempi, associated with a change in racket trajectories from approximately sinusoidal to less symmetrical velocity profiles. Matching results of model simulations give support to a hybrid control model based on optimality, and therefore suggest that optimality principles are applicable to the sensorimotor control of complex movements such as ball bouncing.

Phase IV of Early Restoration | NOAA Gulf Spill Restoration

Science.gov Websites

Trustees published the Final Phase IV Early Restoration Plan and Environmental Assessments. The plan habitats. Useful Links: Final Phase IV Early Restoration Plan and Environmental Assessments (pdf, 4.8 MB ) Final Phase IV Early Restoration Plan and Environmental Assessments Executive Summary (pdf, 729 KB

A key phase in the recruitment dynamics of coral reef fishes: post-settlement transition

USGS Publications Warehouse

Kaufman, L.; Ebersole, J.L.; Beets, Jim; McIvor, Carole

1992-01-01

Recent studies of recruitment dynamics in demersal fishes have placed major emphasis on presettlement mortality, and little on events bridging late larval and early juvenile periods. Observations on 68 taxa of Caribbean coral reef fishes before and during settlement revealed the existence of a distinct post-settlement life phase called the transition juvenile, associated with the act of recruitment. Transition juveniles were found as solitary individuals, in conspecific groups, or in heterospecific groups. The groups were either uniform or heterogenous in appearance. The complexity of the transition phase and its apparently widespread occurrence in coral reef fishes suggests that important aspects of population structure may be determined between settlement and first appearance as a full-fledged juvenile.

Bouncing cosmologies via modified gravity in the ADM formalism: Application to loop quantum cosmology

NASA Astrophysics Data System (ADS)

de Haro, Jaume; Amorós, Jaume

2018-03-01

We consider the Arnowitt-Deser-Misner formalism as a tool to build bouncing cosmologies. In this approach, the foliation of the spacetime has to be fixed in order to go beyond general relativity modifying the gravitational sector. Once a preferred slicing, which we choose based on the matter content of the Universe following the spirit of Weyl's postulate, has been fixed, f theories depending on the extrinsic and intrinsic curvature of the slicing are covariant for all the reference frames preserving the foliation; i.e., the constraint and dynamical equations have the same form for all these observers. Moreover, choosing multivalued f functions, bouncing backgrounds emerge in a natural way. In fact, the simplest is the one corresponding to holonomy corrected loop quantum cosmology. The final goal of this work is to provide the equations of perturbations which, unlike the full equations, become gauge invariant in this theory, and apply them to the so-called matter bounce scenario.

Bounce Rock-A shergottite-like basalt encountered at Meridiani Planum, Mars

USGS Publications Warehouse

Zipfel, J.; Schroder, C.; Jolliff, B.L.; Gellert, Ralf; Herkenhoff, K. E.; Rieder, R.; Anderson, R.; Bell, J.F.; Brückner, J.; Crisp, J.A.; Christensen, P.R.; Clark, B. C.; de Souza, P.A.; Dreibus, G.; D'uston, C.; Economou, T.; Gorevan, S.P.; Hahn, B.C.; Klingelhofer, G.; McCoy, T.J.; McSween, H.Y.; Ming, D. W.; Morris, R.V.; Rodionov, D.S.; Squyres, S. W.; Wanke, H.; Wright, S.P.; Wyatt, M.B.; Yen, A. S.

2011-01-01

The Opportunity rover of the Mars Exploration Rover mission encountered an isolated rock fragment with textural, mineralogical, and chemical properties similar to basaltic shergottites. This finding was confirmed by all rover instruments, and a comprehensive study of these results is reported here. Spectra from the miniature thermal emission spectrometer and the Panoramic Camera reveal a pyroxene-rich mineralogy, which is also evident in M??ssbauer spectra and in normative mineralogy derived from bulk chemistry measured by the alpha particle X-ray spectrometer. The correspondence of Bounce Rock's chemical composition with the composition of certain basaltic shergottites, especially Elephant Moraine (EET) 79001 lithology B and Queen Alexandra Range (QUE) 94201, is very close, with only Cl, Fe, and Ti exhibiting deviations. Chemical analyses further demonstrate characteristics typical of Mars such as the Fe/Mn ratio and P concentrations. Possible shock features support the idea that Bounce Rock was ejected from an impact crater, most likely in the Meridiani Planum region. Bopolu crater, 19.3km in diameter, located 75km to the southwest could be the source crater. To date, no other rocks of this composition have been encountered by any of the rovers on Mars. The finding of Bounce Rock by the Opportunity rover provides further direct evidence for an origin of basaltic shergottite meteorites from Mars. ?? The Meteoritical Society, 2011.

Bounce Rock - A shergottite-like basalt encountered at Meridiani Planum, Mars

NASA Astrophysics Data System (ADS)

Zipfel, Jutta; Schräder, Christian; Jolliff, Bradley L.; Gellert, Ralf; Herkenhoff, Kenneth E.; Rieder, Rudolf; Anderson, Robert; Bell, James F., III; Brückner, Johannes; Crisp, Joy A.; Christensen, Philip R.; Clark, Benton C.; de Souza, Paulo A., Jr.; Dreibus, Gerlind; D'Uston, Claude; Economou, Thanasis; Gorevan, Steven P.; Hahn, Brian C.; Klingelhäfer, Göstar; McCoy, Timothy J.; McSween, Harry Y., Jr.; Ming, Douglas W.; Morris, Richard V.; Rodionov, Daniel S.; Squyres, Steven W.; Wńnke, Heinrich; Wright, Shawn P.; Wyatt, Michael B.; Yen, Albert S.

2011-01-01

Abstract- The Opportunity rover of the Mars Exploration Rover mission encountered an isolated rock fragment with textural, mineralogical, and chemical properties similar to basaltic shergottites. This finding was confirmed by all rover instruments, and a comprehensive study of these results is reported here. Spectra from the miniature thermal emission spectrometer and the Panoramic Camera reveal a pyroxene-rich mineralogy, which is also evident in Mössbauer spectra and in normative mineralogy derived from bulk chemistry measured by the alpha particle X-ray spectrometer. The correspondence of Bounce Rock’s chemical composition with the composition of certain basaltic shergottites, especially Elephant Moraine (EET) 79001 lithology B and Queen Alexandra Range (QUE) 94201, is very close, with only Cl, Fe, and Ti exhibiting deviations. Chemical analyses further demonstrate characteristics typical of Mars such as the Fe/Mn ratio and P concentrations. Possible shock features support the idea that Bounce Rock was ejected from an impact crater, most likely in the Meridiani Planum region. Bopolu crater, 19.3 km in diameter, located 75 km to the southwest could be the source crater. To date, no other rocks of this composition have been encountered by any of the rovers on Mars. The finding of Bounce Rock by the Opportunity rover provides further direct evidence for an origin of basaltic shergottite meteorites from Mars.

Model of rhythmic ball bouncing using a visually controlled neural oscillator.

PubMed

Avrin, Guillaume; Siegler, Isabelle A; Makarov, Maria; Rodriguez-Ayerbe, Pedro

2017-10-01

The present paper investigates the sensory-driven modulations of central pattern generator dynamics that can be expected to reproduce human behavior during rhythmic hybrid tasks. We propose a theoretical model of human sensorimotor behavior able to account for the observed data from the ball-bouncing task. The novel control architecture is composed of a Matsuoka neural oscillator coupled with the environment through visual sensory feedback. The architecture's ability to reproduce human-like performance during the ball-bouncing task in the presence of perturbations is quantified by comparison of simulated and recorded trials. The results suggest that human visual control of the task is achieved online. The adaptive behavior is made possible by a parametric and state control of the limit cycle emerging from the interaction of the rhythmic pattern generator, the musculoskeletal system, and the environment. NEW & NOTEWORTHY The study demonstrates that a behavioral model based on a neural oscillator controlled by visual information is able to accurately reproduce human modulations in a motor action with respect to sensory information during the rhythmic ball-bouncing task. The model attractor dynamics emerging from the interaction between the neuromusculoskeletal system and the environment met task requirements, environmental constraints, and human behavioral choices without relying on movement planning and explicit internal models of the environment. Copyright © 2017 the American Physiological Society.

Gene expression profiles of Vibrio parahaemolyticus in the early stationary phase.

PubMed

Meng, L; Alter, T; Aho, T; Huehn, S

2015-09-01

Vibrio (V.) parahaemolyticus is an aquatic bacterium capable of causing foodborne gastroenteritis. In the environment or the food chain, V. parahaemolyticus cells are usually forced into the stationary phase, the common phase for bacterial survival in the environment. So far, little is known about whole genomic expression of V. parahaemolyticus in the early stationary phase compared with the exponential growth phase. We performed whole transcriptomic profiling of V. parahaemolyticus cells in both phases (exponential and early stationary phase). Our data showed in total that 172 genes were induced in early stationary phase, while 61 genes were repressed in early stationary phase compared with the exponential phase. Three functional categories showed stable gene expression in the early stationary phase. Eleven functional categories showed that up-regulation of genes was dominant over down-regulation in the early stationary phase. Although genes related to endogenous metabolism were repressed in the early stationary phase, massive regulation of gene expression occurred in the early stationary phase, indicating the expressed gene set of V. parahaemolyticus in the early stationary phase impacts environmental survival. Vibrio (V.) parahaemolyticus is one of the main bacterial causes of foodborne intestinal infections. This bacterium usually is forced into stationary phase in the environment, which includes, e.g. seafood. When bacteria are in stationary phase, physiological changes can lead to a resistance to many stresses, including physical and chemical challenges during food processing. To the best of our knowledge, highlighting the whole genome expression changes in the early stationary phase compared with exponential phase, as well as the investigation of physiological changes of V. parahaemolyticus such as the survival mechanism in the stationary phase has been the very first study in this field. © 2015 The Society for Applied Microbiology.

Worldwide isotope ratios of the Fukushima release and early-phase external dose reconstruction

PubMed Central

Chaisan, Kittisak; Smith, Jim T.; Bossew, Peter; Kirchner, Gerald; Laptev, Gennady V.

2013-01-01

Measurements of radionuclides (RNs) in air made worldwide following the Fukushima accident are quantitatively compared with air and soil measurements made in Japan. Isotopic ratios RN:137Cs of 131I, 132Te, 134,136Cs, are correlated with distance from release. It is shown, for the first time, that both within Japan and globally, ratios RN:137Cs in air were relatively constant for primarily particle associated radionuclides (134,136Cs; 132Te) but that 131I shows much lower local (<80 km) isotope ratios in soils relative to 137Cs. Derived isotope ratios are used to reconstruct external dose rate during the early phase post-accident. Model “blind” tests show more than 95% of predictions within a factor of two of measurements from 15 sites to the north, northwest and west of the power station. It is demonstrated that generic isotope ratios provide a sound basis for reconstruction of early-phase external dose rates in these most contaminated areas. PMID:24018776

Modeling waves forced by a drop bouncing on a vibrating bath

NASA Astrophysics Data System (ADS)

Turton, Sam; Rosales, Ruben; Bush, John

2017-11-01

We study the wavefield generated by a droplet bouncing on a bath of silicon oil undergoing vertical oscillations. Such droplets may bounce indefinitely below the Faraday threshold, and in certain parameter regimes destabilize into a walking state in which they are propelled by their own wavefield. While previous theoretical models have rationalize the behavior of single droplets, difficulties have arisen in rationalizing the behavior of multi-droplet systems. We here present a refined wave model that allows us to do so. In particular, we give a detailed account of the spatio-temporal decay of the waves, in addition to the couping between the wave amplitude and modulations in the droplet's vertical dynamics. Our analytic model is compared with the results of direct numerical simulations and experiments. We gratefully acknowledge the financial support of the NSF.

Discharge destination's effect on bounce-back risk in Black, White, and Hispanic acute ischemic stroke patients.

PubMed

Kind, Amy J H; Smith, Maureen A; Liou, Jinn-Ing; Pandhi, Nancy; Frytak, Jennifer R; Finch, Michael D

2010-02-01

To determine whether racial and ethnic effects on bounce-back risk (ie, movement to settings of higher care intensity within 30 d of hospital discharge) in acute stroke patients vary depending on initial posthospital discharge destination. Retrospective analysis of administrative data. Four hundred twenty-two hospitals, southern/eastern United States. All Medicare beneficiaries 65 years or more with hospitalization for acute ischemic stroke within one of the 422 target hospitals during the years 1999 or 2000 (N=63,679). Not applicable. Adjusted predicted probabilities for discharge to and for bouncing back from each initial discharge site (ie, home, home with home health care, skilled nursing facility [SNF], or rehabilitation center) by race (ie, black, white, and Hispanic). Models included sociodemographics, comorbidities, stroke severity, and length of stay. Blacks and Hispanics were significantly more likely to be discharged to home health care (blacks=21% [95% confidence interval (CI), 19.9-22.8], Hispanic=19% [17.1-21.7] vs whites=16% [15.5-16.8]) and less likely to be discharged to SNFs (blacks=26% [95% CI, 23.6-29.3], Hispanics=28% [25.4-31.6] vs whites=33% [31.8-35.1]) than whites. However, blacks and Hispanics were significantly more likely to bounce back when discharged to SNFs than whites (blacks=26% [95% CI, 24.2-28.6], Hispanics=28% [24-32.6] vs whites=21% [20.3-21.9]). Hispanics had a lower risk of bouncing back when discharged home than either blacks or whites (Hispanics=14% [95% CI, 11.3-17] vs blacks=20% [18.4-22.2], whites=18% [16.8-18.3]). Patients discharged to home health care or rehabilitation centers demonstrated no significant differences in bounce-back risk. Racial/ethnic bounce-back risk differs depending on initial discharge destination. Additional research is needed to fully understand this variation in effect. Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Does Post-task Declarative Learning Have an Influence on Early Motor Memory Consolidation Over Day? An fMRI Study

PubMed Central

Rothkirch, Inken; Wolff, Stephan; Margraf, Nils G.; Pedersen, Anya; Witt, Karsten

2018-01-01

Previous studies demonstrated the influence of the post-learning period on procedural motor memory consolidation. In an early period after the acquisition, motor skills are vulnerable to modifications during wakefulness. Indeed, specific interventions such as world-list learning within this early phase of motor memory consolidation seem to enhance motor performance as an indicator for successful consolidation. This finding highlights the idea that manipulations of procedural and declarative memory systems during the early phase of memory consolidation over wakefulness may influence off-line consolidation. Using functional magnetic resonance imaging (fMRI) during initial motor sequence learning and motor sequence recall, we indirectly assess the influence of a secondary task taken place in the early phase of memory consolidation. All participants were scanned using fMRI during the learning phase of a serial reaction time task (SRTT) at 8 a.m. Afterwards, they were randomly assigned to one of five conditions. One group performed a declarative verbal, one a declarative nonverbal learning task. Two groups worked on attention tasks. A control group passed a resting condition. Participants stayed awake the whole day and performed the SRTT in the MRI scanner 12 h later at 8 p.m. At the behavioral level, the analysis of the reaction times failed to show a significant group difference. The primary analysis assessing fMRI data based on the contrast (sequence – random) between learning and retrieval also did not show any significant group differences. Therefore, our main analysis do not support the hypothesis that a secondary task influences the retrieval of the SRTT. In a more liberal fMRI analysis, we compared only the sequence blocks of the SRTT from learning to recall. BOLD signal decreased in the ipsilateral cerebellum and the supplementary motor area solely in the verbal learning group. Although our primary analysis failed to show significant changes between our

Does Post-task Declarative Learning Have an Influence on Early Motor Memory Consolidation Over Day? An fMRI Study.

PubMed

Rothkirch, Inken; Wolff, Stephan; Margraf, Nils G; Pedersen, Anya; Witt, Karsten

2018-01-01

Previous studies demonstrated the influence of the post-learning period on procedural motor memory consolidation. In an early period after the acquisition, motor skills are vulnerable to modifications during wakefulness. Indeed, specific interventions such as world-list learning within this early phase of motor memory consolidation seem to enhance motor performance as an indicator for successful consolidation. This finding highlights the idea that manipulations of procedural and declarative memory systems during the early phase of memory consolidation over wakefulness may influence off-line consolidation. Using functional magnetic resonance imaging (fMRI) during initial motor sequence learning and motor sequence recall, we indirectly assess the influence of a secondary task taken place in the early phase of memory consolidation. All participants were scanned using fMRI during the learning phase of a serial reaction time task (SRTT) at 8 a.m. Afterwards, they were randomly assigned to one of five conditions. One group performed a declarative verbal, one a declarative nonverbal learning task. Two groups worked on attention tasks. A control group passed a resting condition. Participants stayed awake the whole day and performed the SRTT in the MRI scanner 12 h later at 8 p.m. At the behavioral level, the analysis of the reaction times failed to show a significant group difference. The primary analysis assessing fMRI data based on the contrast (sequence - random) between learning and retrieval also did not show any significant group differences. Therefore, our main analysis do not support the hypothesis that a secondary task influences the retrieval of the SRTT. In a more liberal fMRI analysis, we compared only the sequence blocks of the SRTT from learning to recall. BOLD signal decreased in the ipsilateral cerebellum and the supplementary motor area solely in the verbal learning group. Although our primary analysis failed to show significant changes between our groups

Anesthesia-Induced Hypothermia Attenuates Early-Phase Blood-Brain Barrier Disruption but Not Infarct Volume following Cerebral Ischemia.

PubMed

Liu, Yu-Cheng; Lee, Yu-Da; Wang, Hwai-Lee; Liao, Kate Hsiurong; Chen, Kuen-Bao; Poon, Kin-Shing; Pan, Yu-Ling; Lai, Ted Weita

2017-01-01

Blood-brain barrier (BBB) disruption is thought to facilitate the development of cerebral infarction after a stroke. In a typical stroke model (such as the one used in this study), the early phase of BBB disruption reaches a peak 6 h post-ischemia and largely recovers after 8-24 h, whereas the late phase of BBB disruption begins 48-58 h post-ischemia. Because cerebral infarct develops within 24 h after the onset of ischemia, and several therapeutic agents have been shown to reduce the infarct volume when administered at 6 h post-ischemia, we hypothesized that attenuating BBB disruption at its peak (6 h post-ischemia) can also decrease the infarct volume measured at 24 h. We used a mouse stroke model obtained by combining 120 min of distal middle cerebral arterial occlusion (dMCAo) with ipsilateral common carotid arterial occlusion (CCAo). This model produced the most reliable BBB disruption and cerebral infarction compared to other models characterized by a shorter duration of ischemia or obtained with dMCAO or CCAo alone. The BBB permeability was measured by quantifying Evans blue dye (EBD) extravasation, as this tracer has been shown to be more sensitive for the detection of early-phase BBB disruption compared to other intravascular tracers that are more appropriate for detecting late-phase BBB disruption. We showed that a 1 h-long treatment with isoflurane-anesthesia induced marked hypothermia and attenuated the peak of BBB disruption when administered 6 h after the onset of dMCAo/CCAo-induced ischemia. We also demonstrated that the inhibitory effect of isoflurane was hypothermia-dependent because the same treatment had no effect on ischemic BBB disruption when the mouse body temperature was maintained at 37°C. Importantly, inhibiting the peak of BBB disruption by hypothermia had no effect on the volume of brain infarct 24 h post-ischemia. In conclusion, inhibiting the peak of BBB disruption is not an effective neuroprotective strategy, especially in comparison

Generalized holographic dark energy and bouncing cosmology in Gauss-Bonnet gravity

NASA Astrophysics Data System (ADS)

Makarenko, Andrey N.; Myagky, Alexander N.

We found out that F(𝒢) gravity theory can be rewritten in the holographic language at the level of background equivalence. The examples of the bouncing cosmological models in F(𝒢) gravity are considered in details.

Effect of collision duration on the chaotic dynamics of a ball bouncing on a vertically vibrating plate

NASA Astrophysics Data System (ADS)

Jiang, Z. H.; Liang, Z. J.; Wu, A. C.; Zheng, R. H.

2018-03-01

Experiments have been performed to study the chaotic dynamics of a ball bouncing on a vertically vibrating plate. The velocity dependence of collision duration and coefficient of restitution is determined, and phase portraits of chaotic structures for the flight time and the relative collision velocities are obtained. Numerical calculations are carried out to examine the effects of velocity-dependent collision duration on the ball dynamics. It is revealed that when the collision is instantaneous, sticking solutions are always observed, whereas when the collision duration is taken into account, sticking solutions are destroyed and thereby chaos behaviors are induced.

Increasing Fractional Doses Increases the Probability of Benign PSA Bounce in Patients Undergoing Definitive HDR Brachytherapy for Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hauck, Carlin R.; Ye, Hong; Chen, Peter Y.

Purpose: Prostate-specific antigen (PSA) bounce is a temporary elevation of the PSA level above a prior nadir. The purpose of this study was to determine whether the frequency of a PSA bounce following high-dose-rate (HDR) interstitial brachytherapy for the treatment of prostate cancer is associated with individual treatment fraction size. Methods and Materials: Between 1999 and 2014, 554 patients underwent treatment of low- or intermediate-risk prostate cancer with definitive HDR brachytherapy as monotherapy and had ≥3 subsequent PSA measurements. Four different fraction sizes were used: 950 cGy × 4 fractions, 1200 cGy × 2 fractions, 1350 cGy × 2 fractions, 1900 cGy × 1more » fraction. Four definitions of PSA bounce were applied: ≥0.2, ≥0.5, ≥1.0, and ≥2.0 ng/mL above the prior nadir with a subsequent return to the nadir. Results: The median follow-up period was 3.7 years. The actuarial 3-year rate of PSA bounce for the entire cohort was 41.3%, 28.4%, 17.4%, and 6.8% for nadir +0.2, +0.5, +1.0, and +2.0 ng/mL, respectively. The 3-year rate of PSA bounce >0.2 ng/mL was 42.2%, 32.1%, 41.0%, and 59.1% for the 950-, 1200-, 1350-, and 1900-cGy/fraction levels, respectively (P=.002). The hazard ratio for bounce >0.2 ng/mL for patients receiving a single fraction of 1900 cGy compared with those receiving treatment in multiple fractions was 1.786 (P=.024). For patients treated with a single 1900-cGy fraction, the 1-, 2-, and 3-year rates of PSA bounce exceeding the Phoenix biochemical failure definition (nadir +2 ng/mL) were 4.5%, 18.7%, and 18.7%, respectively, higher than the rates for all other administered dose levels (P=.025). Conclusions: The incidence of PSA bounce increases with single-fraction HDR treatment. Knowledge of posttreatment PSA kinetics may aid in decision making regarding management of potential biochemical failures.« less

Increasing Fractional Doses Increases the Probability of Benign PSA Bounce in Patients Undergoing Definitive HDR Brachytherapy for Prostate Cancer.

PubMed

Hauck, Carlin R; Ye, Hong; Chen, Peter Y; Gustafson, Gary S; Limbacher, Amy; Krauss, Daniel J

2017-05-01

Prostate-specific antigen (PSA) bounce is a temporary elevation of the PSA level above a prior nadir. The purpose of this study was to determine whether the frequency of a PSA bounce following high-dose-rate (HDR) interstitial brachytherapy for the treatment of prostate cancer is associated with individual treatment fraction size. Between 1999 and 2014, 554 patients underwent treatment of low- or intermediate-risk prostate cancer with definitive HDR brachytherapy as monotherapy and had ≥3 subsequent PSA measurements. Four different fraction sizes were used: 950 cGy × 4 fractions, 1200 cGy × 2 fractions, 1350 cGy × 2 fractions, 1900 cGy × 1 fraction. Four definitions of PSA bounce were applied: ≥0.2, ≥0.5, ≥1.0, and ≥2.0 ng/mL above the prior nadir with a subsequent return to the nadir. The median follow-up period was 3.7 years. The actuarial 3-year rate of PSA bounce for the entire cohort was 41.3%, 28.4%, 17.4%, and 6.8% for nadir +0.2, +0.5, +1.0, and +2.0 ng/mL, respectively. The 3-year rate of PSA bounce >0.2 ng/mL was 42.2%, 32.1%, 41.0%, and 59.1% for the 950-, 1200-, 1350-, and 1900-cGy/fraction levels, respectively (P=.002). The hazard ratio for bounce >0.2 ng/mL for patients receiving a single fraction of 1900 cGy compared with those receiving treatment in multiple fractions was 1.786 (P=.024). For patients treated with a single 1900-cGy fraction, the 1-, 2-, and 3-year rates of PSA bounce exceeding the Phoenix biochemical failure definition (nadir +2 ng/mL) were 4.5%, 18.7%, and 18.7%, respectively, higher than the rates for all other administered dose levels (P=.025). The incidence of PSA bounce increases with single-fraction HDR treatment. Knowledge of posttreatment PSA kinetics may aid in decision making regarding management of potential biochemical failures. Copyright © 2017 Elsevier Inc. All rights reserved.

Application of CHESS single-bounce capillaries at synchrotron beamlines

NASA Astrophysics Data System (ADS)

Huang, R.; Szebenyi, T.; Pfeifer, M.; Woll, A.; Smilgies, D.-M.; Finkelstein, K.; Dale, D.; Wang, Y.; Vila-Comamala, J.; Gillilan, R.; Cook, M.; Bilderback, D. H.

2014-03-01

Single-bounce capillaries are achromatic X-ray focusing optics that can provide efficient and high demagnification focusing with large numerical apertures. Capillary fabrication at CHESS can be customized according to specific application requirements. Exemplary applications are reviewed in this paper, as well as recent progress on condensers for high-resolution transmission X-ray microscopy and small focal size capillaries.

Bouncing and emergent cosmologies from Arnowitt–Deser–Misner RG flows

NASA Astrophysics Data System (ADS)

Bonanno, Alfio; Gionti, S. J. Gabriele; Platania, Alessia

2018-03-01

Asymptotically safe gravity provides a framework for the description of gravity from the trans-Planckian regime to cosmological scales. According to this scenario, the cosmological constant and Newton’s coupling are functions of the energy scale whose evolution is dictated by the renormalization group (RG) equations. The formulation of the RG equations on foliated spacetimes, based on the Arnowitt–Deser–Misner (ADM) formalism, furnishes a natural way to construct the RG energy scale from the spectrum of the Laplacian operator on the spatial slices. Combining this idea with an RG improvement procedure, in this work we study quantum gravitational corrections to the Einstein–Hilbert action on Friedmann–Lemaître–Robertson–Walker backgrounds. The resulting quantum-corrected Friedmann equations can give rise to both bouncing cosmologies and emergent Universe solutions. Our bouncing models do not require the presence of exotic matter and emergent Universe solutions can be constructed for any allowed topology of the spatial slices.

Transversal stability of the bouncing ball on a concave surface.

PubMed

Chastaing, J-Y; Pillet, G; Taberlet, N; Géminard, J-C

2015-05-01

A ball bouncing repeatedly on a vertically vibrating surface constitutes the famous "bouncing ball" problem, a nonlinear system used in the 1980s, and still in use nowadays, to illustrate the route to chaos by period doubling. In experiments, in order to avoid the ball escape that would be inevitable with a flat surface, a concave lens is often used to limit the horizontal motion. However, we observe experimentally that the system is not stable. The ball departs from the system axis and exhibits a pendular motion in the permanent regime. We propose theoretical arguments to account for the decrease of the growth rate and of the asymptotic-size of the trajectory when the frequency of the vibration is increased. The instability is very sensitive to the physics of the contacts, which makes it a potentially interesting way to study the collisions rules, or to test the laws used in numerical studies of granular matter.

3D MR-Spectroscopic Imaging Assessment of Metabolic Activity in the Prostate During the PSA 'Bounce' Following {sup 125}Iodine Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kirilova, Anna; Damyanovich, Andrei; Crook, Juanita, E-mail: jcrook@bccancer.bc.c

2011-02-01

Purpose: A temporary increase in prostate-specific antigen (PSA) values is observed in 30%-40% of men following {sup 125} I brachytherapy (BT) for prostate cancer. We present the results of a study to characterize prostate metabolic activity during the PSA 'bounce' and to correlate metabolic changes with PSA levels using three-dimensional magnetic resonance spectroscopic imaging (3D-MRSI). Methods and Materials: 3D-MRSI was performed in 24 patients during the PSA bounce. Eight of these had also had a baseline 3D-MRSI scan before BT for the purpose of tumor mapping. The 3D-MRSI was repeated at 6- and 12-month intervals, and PSA levels were monitoredmore » every 3 months. Twenty-one of the patients had favorable-risk prostate cancer, and 3 had intermediate risk. Results: The choline+creatine signal intensity, although markedly reduced, was observable following BT. Diffuse activity not corresponding to original biopsy-positive sites was observed in 22 cases, and 2 cases were documented to have local recurrence. No statistically significant correlation between metabolic activity and PSA levels at each interval was found. Conclusion: Post-BT prostate 3D-MRSI shows evidence of diffuse metabolic activity unrelated to residual malignancy. This supports the benign nature of the PSA bounce and suggests an inflammatory etiology. In the situation of a rising PSA, observation of focal activity on MRI/3D-MRSI could be a useful adjunct to suggest local recurrence at an earlier interval after brachytherapy when prostate biopsies would still be unhelpful. Longer follow-up is necessary to confirm the complex relationship between metabolic activity and PSA levels.« less

Pharmacogenomics in early-phase clinical development

PubMed Central

Burt, Tal; Dhillon, Savita

2015-01-01

Pharmacogenomics (PGx) offers the promise of utilizing genetic fingerprints to predict individual responses to drugs in terms of safety, efficacy and pharmacokinetics. Early-phase clinical trial PGx applications can identify human genome variations that are meaningful to study design, selection of participants, allocation of resources and clinical research ethics. Results can inform later-phase study design and pipeline developmental decisions. Nevertheless, our review of the clinicaltrials.gov database demonstrates that PGx is rarely used by drug developers. Of the total 323 trials that included PGx as an outcome, 80% have been conducted by academic institutions after initial regulatory approval. Barriers for the application of PGx are discussed. We propose a framework for the role of PGx in early-phase drug development and recommend PGx be universally considered in study design, result interpretation and hypothesis generation for later-phase studies, but PGx results from underpowered studies should not be used by themselves to terminate drug-development programs. PMID:23837482

Investigating the Relationship between the Half-Life Decay of the Height and the Coefficient of Restitution of Bouncing Balls Using a Microcomputer-Based Laboratory

ERIC Educational Resources Information Center

Amrani, D.

2010-01-01

This pedagogical activity is aimed at students using a computer-learning environment with advanced tools for data analysis. It investigates the relationship between the coefficient of restitution and the way the heights of different bouncing balls decrease in a number of bounces with time. The time between successive ball bounces, or…

Space-time slicing in Horndeski theories and its implications for non-singular bouncing solutions

NASA Astrophysics Data System (ADS)

Ijjas, Anna

2018-02-01

In this paper, we show how the proper choice of gauge is critical in analyzing the stability of non-singular cosmological bounce solutions based on Horndeski theories. We show that it is possible to construct non-singular cosmological bounce solutions with classically stable behavior for all modes with wavelengths above the Planck scale where: (a) the solution involves a stage of null-energy condition violation during which gravity is described by a modification of Einstein's general relativity; and (b) the solution reduces to Einstein gravity both before and after the null-energy condition violating stage. Similar considerations apply to galilean genesis scenarios.

Enabling Parametric Optimal Ascent Trajectory Modeling During Early Phases of Design

NASA Technical Reports Server (NTRS)

Holt, James B.; Dees, Patrick D.; Diaz, Manuel J.

2015-01-01

-modal due to the interaction of various constraints. Additionally, when these obstacles are coupled with The Program to Optimize Simulated Trajectories [1] (POST), an industry standard program to optimize ascent trajectories that is difficult to use, it requires expert trajectory analysts to effectively optimize a vehicle's ascent trajectory. As it has been pointed out, the paradigm of trajectory optimization is still a very manual one because using modern computational resources on POST is still a challenging problem. The nuances and difficulties involved in correctly utilizing, and therefore automating, the program presents a large problem. In order to address these issues, the authors will discuss a methodology that has been developed. The methodology is two-fold: first, a set of heuristics will be introduced and discussed that were captured while working with expert analysts to replicate the current state-of-the-art; secondly, leveraging the power of modern computing to evaluate multiple trajectories simultaneously, and therefore, enable the exploration of the trajectory's design space early during the pre-conceptual and conceptual phases of design. When this methodology is coupled with design of experiments in order to train surrogate models, the authors were able to visualize the trajectory design space, enabling parametric optimal ascent trajectory information to be introduced with other pre-conceptual and conceptual design tools. The potential impact of this methodology's success would be a fully automated POST evaluation suite for the purpose of conceptual and preliminary design trade studies. This will enable engineers to characterize the ascent trajectory's sensitivity to design changes in an arbitrary number of dimensions and for finding settings for trajectory specific variables, which result in optimal performance for a "dialed-in" launch vehicle design. The effort described in this paper was developed for the Advanced Concepts Office [2] at NASA Marshall

Duration of inflation and conditions at the bounce as a prediction of effective isotropic loop quantum cosmology

NASA Astrophysics Data System (ADS)

Linsefors, Linda; Barrau, Aurelien

2013-06-01

Loop quantum cosmology with a scalar field is known to be closely linked with an inflationary phase. In this article, we study probabilistic predictions for the duration of slow-roll inflation, by assuming a minimalist massive scalar field as the main content of the Universe. The phase of the field in its “prebounce” oscillatory state is taken as a natural random parameter. We find that the probability for a given number of inflationary e-folds is quite sharply peaked around 145, which is consistent with the most favored minimum values. In this precise sense, a satisfactory inflation is therefore a clear prediction of loop gravity. In addition, we derive an original and stringent upper limit on the Barbero-Immirzi parameter. The general picture of inflation, superinflation, deflation, and superdeflation is also much clarified in the framework of bouncing cosmologies.

New possibilities in supernova accretion phase from dense matter effect

NASA Astrophysics Data System (ADS)

Chakraborty, S.; Mirizzi, A.; Saviano, N.

2012-07-01

We carry out a detailed analysis of the supernova (SN) neutrino flavor evolution during the accretion phase (at post-bounce times tpb <= 500 ms), characterizing the SN ν signal by recent hydrodynamical simulations. We find that trajectory-dependent multi-angle effects, associated with the dense ordinary matter suppress collective oscillations, that would have been induced by ν-ν interactions in the deepest SN regions. The matter suppression implies that neutrino oscillations will start outside the neutrino decoupling region and therefore will have a negligible impact on the neutrino heating and the explosion dynamics. Furthermore, the possible detection of the next galactic SN neutrino signal from the accretion phase, based on the usual Mikheyev-Smirnov-Wolfenstein effect in the SN mantle and Earth matter effects, can reveal the neutrino mass hierarchy in the likely case that the mixing angle θ13 is not very small.

Dynamics of a bouncing ball

NASA Astrophysics Data System (ADS)

Chastaing, J.-Y.; Bertin, E.; Géminard, J.-C.

2015-06-01

We describe an experiment dedicated to the study of the trajectories of a ball bouncing on a vibrating plate. Using an experimental device of our own design, it is possible to impose arbitrary trajectories on the plate and we show that the entire trajectory of the ball can be reconstructed solely from measurement of the times the ball hits the plate. In this paper, we make use of our apparatus to introduce the notion of dissipative collisions and to propose three different ways to measure the associated restitution coefficient. We then report on correlations in the chaotic regime and theoretically discuss the complex patterns that are exhibited in the case of a sinusoidal vibration. Lastly, we show that the use of an aperiodic driving vibration makes it possible to minimize part of these correlations.

Energetic costs of producing muscle work and force in a cyclical human bouncing task

PubMed Central

Kuo, Arthur D.

2011-01-01

Muscles expend energy to perform active work during locomotion, but they may also expend significant energy to produce force, for example when tendons perform much of the work passively. The relative contributions of work and force to overall energy expenditure are unknown. We therefore measured the mechanics and energetics of a cyclical bouncing task, designed to control for work and force. We hypothesized that near bouncing resonance, little work would be performed actively by muscle, but the cyclical production of force would cost substantial metabolic energy. Human subjects (n = 9) bounced vertically about the ankles at inversely proportional frequencies (1–4 Hz) and amplitudes (15–4 mm), such that the overall rate of work performed on the body remained approximately constant (0.30 ± 0.06 W/kg), but the forces varied considerably. We used parameter identification to estimate series elasticity of the triceps surae tendon, as well as the work performed actively by muscle and passively by tendon. Net metabolic energy expenditure for bouncing at 1 Hz was 1.15 ± 0.31 W/kg, attributable mainly to active muscle work with an efficiency of 24 ± 3%. But at 3 Hz (near resonance), most of the work was performed passively, so that active muscle work could account for only 40% of the net metabolic rate of 0.76 ± 0.28 W/kg. Near resonance, a cost for cyclical force that increased with both amplitude and frequency of force accounted for at least as much of the total energy expenditure as a cost for work. Series elasticity reduces the need for active work, but energy must still be expended for force production. PMID:21212245

Ring Current He Ion Control by Bounce Resonant ULF Waves

NASA Astrophysics Data System (ADS)

Kim, Hyomin; Gerrard, Andrew J.; Lanzerotti, Louis J.; Soto-Chavez, Rualdo; Cohen, Ross J.; Manweiler, Jerry W.

2017-12-01

Ring current energy He ion (˜65 keV to ˜520 keV) differential flux data from the Radiation Belt Storm Probe Ion Composition Experiment (RBSPICE) instrument aboard the Van Allan Probes spacecraft show considerable variability during quiet solar wind and geomagnetic time periods. Such variability is apparent from orbit to orbit (˜9 h) of the spacecraft and is observed to be ˜50-100% of the nominal flux. Using data from the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) instrument, also aboard the Van Allen Probes spacecraft, we identify that a dominant source of this variability is from ULF waveforms with periods of tens of seconds. These periods correspond to the bounce resonant timescales of the ring current He ions being measured by RBSPICE. A statistical survey using the particle and field data for one full spacecraft precession period (approximately 2 years) shows that the wave and He ion flux variations are generally anticorrelated, suggesting the bounce resonant pitch angle scattering process as a major component in the scattering of He ions.

Estimation of Moisture Content of Forest Canopy and Floor from SAR Data Part II: Trunk-Ground Double-Bounce Case

NASA Technical Reports Server (NTRS)

Moghaddam, M.; Saatchi, S.

1996-01-01

Several scattering mechanisms contribute to the total radar backscatter cross section measured by the synthetic aperture radar. These are volume scattering, trunk-ground double-bounce scattering, branch-ground double-bounce scattering, and surface scattering. All of these mechanisms are directly related to the dielectric constant of forest components responsible for that mechanism and their moisture.

Comparison Of Efficacy Of Phenytoin And Levetiracetam For Prevention Of Early Post Traumatic Seizures.

PubMed

Khan, Shahbaz Ali; Bhatti, Sajid Nazir; Khan, Aftab Alam; Khan Afridi, Ehtisham Ahmed; Muhammad, Gul; Gul, Nasim; Zadran, Khalid Khan; Alam, Sudhair; Aurangzeb, Ahsan

2016-01-01

The incidence of early post-traumatic seizures after civilian traumatic brain injury ranges 4-25%. The control of early post-traumatic seizure is mandatory because these acute insults may add secondary damage to the already damaged brain with poor outcome. Prophylactic use of anti-epileptic drugs have been found to be have variable efficacy against early post-traumatic seizures. The objective of this study was to compare the efficacy of Phenytion and Levetiracetam in prevention of early post-traumatic seizures in moderate to severe traumatic brain injury. This randomized controlled trial was conducted in department of Neurosurgery, Ayub Medical College, Abbottabad from March, 2012 to March 2013. The patients with moderate to severe head injury were randomly allocated in two groups. Patients in group A were given phenytoin and patients in group B were given Levetiracetam. Patients were followed for one week to detect efficacy of drug in terms of early post traumatic seizures. The 154 patients included in the study were equally divided into two groups. Out of 154 patients 115 (74.7%) were male while 29 (25.3%) were females. Age of patients ranges from 7-48 (24.15±9.56) years. Ninety one (59.1%) patients had moderate head injury while 63 (40.9%) patients had severe head injury. Phenytoin was effective in preventing early post traumatic seizures in 73 (94.8%) patients whereas Levetiracetam effectively controlled seizures in 70 (90.95%) cases (p-value of .348). There is no statistically significant difference in the efficacy of Phenytoin and Levetiracetam in prophylaxis of early posttraumatic seizures in cases of moderate to severe traumatic brain injury.

Implications of Planck2015 for inflationary, ekpyrotic and anamorphic bouncing cosmologies

NASA Astrophysics Data System (ADS)

Ijjas, Anna; Steinhardt, Paul J.

2016-02-01

The results from Planck2015, when combined with earlier observations from the Wilkinson Microwave Anisotropy Probe, Atacama Cosmology Telescope, South Pole Telescope and other experiments, were the first observations to disfavor the ‘classic’ inflationary paradigm. To satisfy the observational constraints, inflationary theorists have been forced to consider plateau-like inflaton potentials that introduce more parameters and more fine-tuning, problematic initial conditions, multiverse-unpredictability issues, and a new ‘unlikeliness problem’. Some propose turning instead to a ‘postmodern’ inflationary paradigm in which the cosmological properties in our observable Universe are only locally valid and set randomly, with completely different properties (and perhaps even different physical laws) existing in most regions outside our horizon. By contrast, the new results are consistent with the simplest versions of ekpyrotic cyclic models in which the Universe is smoothed and flattened during a period of slow contraction followed by a bounce, and another promising bouncing theory, anamorphic cosmology, has been proposed that can produce distinctive predictions.

Coupling the Leidenfrost effect and elastic deformations to power sustained bouncing

NASA Astrophysics Data System (ADS)

Waitukaitis, Scott R.; Zuiderwijk, Antal; Souslov, Anton; Coulais, Corentin; van Hecke, Martin

2017-11-01

The Leidenfrost effect occurs when an object near a hot surface vaporizes rapidly enough to lift itself up and hover. Although well understood for liquids and stiff sublimable solids, nothing is known about the effect with materials whose stiffness lies between these extremes. Here we introduce a new phenomenon that occurs with vaporizable soft solids--the elastic Leidenfrost effect. By dropping hydrogel spheres onto hot surfaces we find that, rather than hovering, they energetically bounce several times their diameter for minutes at a time. With high-speed video during a single impact, we uncover high-frequency microscopic gap dynamics at the sphere/substrate interface. We show how these otherwise-hidden agitations constitute work cycles that harvest mechanical energy from the vapour and sustain the bouncing. Our findings suggest a new strategy for injecting mechanical energy into a widely used class of soft materials, with potential relevance to fields such as active matter, soft robotics and microfluidics.

Water ring-bouncing on repellent singularities.

PubMed

Chantelot, Pierre; Mazloomi Moqaddam, Ali; Gauthier, Anaïs; Chikatamarla, Shyam S; Clanet, Christophe; Karlin, Ilya V; Quéré, David

2018-03-28

Texturing a flat superhydrophobic substrate with point-like superhydrophobic macrotextures of the same repellency makes impacting water droplets take off as rings, which leads to shorter bouncing times than on a flat substrate. We investigate the contact time reduction on such elementary macrotextures through experiment and simulations. We understand the observations by decomposing the impacting drop reshaped by the defect into sub-units (or blobs) whose size is fixed by the liquid ring width. We test the blob picture by looking at the reduction of contact time for off-centered impacts and for impacts in grooves that produce liquid ribbons where the blob size is fixed by the width of the channel.

Early Post-Operative Outcomes and Blood Product Utilization in Adult Cardiac Surgery- The Post Aprotinin Era

PubMed Central

DeSantis, Stacia; Toole, J. Matthew; Kratz, John M.; Uber, Walter E.; Wheat, Margaret J.; Stroud, Martha R.; Ikonomidis, John S.; Spinale, Francis G.

2011-01-01

Background Aprotinin was a commonly utilized pharmacological agent for homeostasis in cardiac surgery but was discontinued resulting in the extensive use of lysine analogues. This study tested the hypothesis that early post-operative adverse events and blood product utilization would affected in this post-aprotinin era. Methods/Results Adult patients (n=781) undergoing coronary artery bypass (CABG), valve replacement, or both from November 1, 2005-October 31, 2008 at a single institution were included. Multiple logistic regression modeling and propensity scoring were performed on 29 pre-operative and intra-operative variables in patients receiving aprotinin (n=325) or lysine analogues (n=456). The propensity adjusted relative risk (RR;95% confidence interval;CI) for the intra-operative use of packed red blood cells (RR:0.75;CI:0.57–0.99), fresh frozen plasma (RR:0.37;0.21–0.64), and cryoprecipitate (RR:0.06;CI:0.02–0.22) were lower in the aprotinin versus lysine analogue group (all p<0.05). The risk for mortality (RR:0.53;CI:0.16–1.79) and neurological events (RR:0.87;CI:0.35–2.18) remained similar between groups, whereas a trend for reduced risk for renal dysfunction was observed in the aprotinin group. Conclusions In the post-aprotinin era with the exclusive use of lysine analogues, the relative risk of early post-operative outcomes such as mortality and renal dysfunction have not improved, but the risk for the intra-operative use of blood products has increased. Thus, improvements in early post-operative outcomes have not been realized with the discontinued use of aprotinin, but rather increased blood product utilization has occurred with the attendant costs and risks inherent with this strategy. PMID:21911820

Numerical verification of bounce-harmonic resonances in neoclassical toroidal viscosity for tokamaks.

PubMed

Kim, Kimin; Park, Jong-Kyu; Boozer, Allen H

2013-05-03

This Letter presents the first numerical verification for the bounce-harmonic (BH) resonance phenomena of the neoclassical transport in a tokamak perturbed by nonaxisymmetric magnetic fields. The BH resonances were predicted by analytic theories of neoclassical toroidal viscosity (NTV), as the parallel and perpendicular drift motions can be resonant and result in a great enhancement of the radial momentum transport. A new drift-kinetic δf guiding-center particle code, POCA, clearly verified that the perpendicular drift motions can reduce the transport by phase-mixing, but in the BH resonances the motions can form closed orbits and particles radially drift out fast. The POCA calculations on resulting NTV torque are largely consistent with analytic calculations, and show that the BH resonances can easily dominate the NTV torque when a plasma rotates in the perturbed tokamak and therefore, is a critical physics for predicting the rotation and stability in the International Thermonuclear Experimental Reactor.

Comparison of endotoxin and particle bounce in Marple cascade samplers with and without impaction grease.

PubMed

Kirychuk, Shelley P; Reynolds, Stephen J; Koehncke, Niels; Nakatsu, J; Mehaffy, John

2009-01-01

The health of persons engaged in agricultural activities are often related or associated with environmental exposures in their workplace. Accurately measuring, analyzing, and reporting these exposures is paramount to outcomes interpretation. This paper describes issues related to sampling air in poultry barns with a cascade impactor. Specifically, the authors describe how particle bounce can affect measurement outcomes and how the use of impaction grease can impact particle bounce and laboratory analyses such as endotoxin measurements. This project was designed to (1) study the effect of particle bounce in Marple cascade impactors that use polyvinyl chloride (PVC) filters; (2) to determine the effect of impaction grease on endotoxin assays when sampling poultry barn dust. A pilot study was undertaken utilizing six-stage Marple cascade impactors with PVC filters. Distortion of particulate size distributions and the effects of impaction grease on endotoxin analysis in samples of poultry dust distributed into a wind tunnel were studied. Although there was no significant difference in the overall dust concentration between utilizing impaction grease and not, there was a greater than 50% decrease in the mass median aerodynamic diameter (MMAD) values when impaction grease was not utilized. There was no difference in airborne endotoxin concentration or endotoxin MMAD between filters treated with impaction grease and those not treated. The results indicate that particle bounce should be a consideration when sampling poultry barn dust with Marple samplers containing PVC filters with no impaction grease. Careful consideration should be given to the utilization of impaction grease on PVC filters, which will undergo endotoxin analysis, as there is potential for interference, particularly if high or low levels of endotoxin are anticipated.

Evolution of X-ray activity of 1-3 Msun late-type stars in early post-main-sequence phases

NASA Astrophysics Data System (ADS)

Pizzolato, N.; Maggio, A.; Sciortino, S.

2000-09-01

We have investigated the variation of coronal X-ray emission during early post-main-sequence phases for a sample of 120 late-type stars within 100 pc, and with estimated masses in the range 1-3 Msun, based on Hipparcos parallaxes and recent evolutionary models. These stars were observed with the ROSAT/PSPC, and the data processed with the Palermo-CfA pipeline, including detection and evaluation of X-ray fluxes (or upper limits) by means of a wavelet transform algorithm. We have studied the evolutionary history of X-ray luminosity and surface flux for stars in selected mass ranges, including stars with inactive A-type progenitors on the main sequence and lower mass solar-type stars. Our stellar sample suggests a trend of increasing X-ray emission level with age for stars with masses M > 1.5 Msun, and a decline for lower-mass stars. A similar behavior holds for the average coronal temperature, which follows a power-law correlation with the X-ray luminosity, independently of their mass and evolutionary state. We have also studied the relationship between X-ray luminosity and surface rotation rate for stars in the same mass ranges, and how this relationships departs from the Lx ~ vrot2 law followed by main-sequence stars. Our results are interpreted in terms of a magnetic dynamo whose efficiency depends on the stellar evolutionary state through the mass-dependent changes of the stellar internal structure, including the properties of envelope convection and the internal rotation profile.

Running of the spectral index in deformed matter bounce scenarios with Hubble-rate-dependent dark energy

NASA Astrophysics Data System (ADS)

Arab, M.; Khodam-Mohammadi, A.

2018-03-01

As a deformed matter bounce scenario with a dark energy component, we propose a deformed one with running vacuum model (RVM) in which the dark energy density ρ _{Λ } is written as a power series of H^2 and \\dot{H} with a constant equation of state parameter, same as the cosmological constant, w=-1. Our results in analytical and numerical point of views show that in some cases same as Λ CDM bounce scenario, although the spectral index may achieve a good consistency with observations, a positive value of running of spectral index (α _s) is obtained which is not compatible with inflationary paradigm where it predicts a small negative value for α _s. However, by extending the power series up to H^4, ρ _{Λ }=n_0+n_2 H^2+n_4 H^4, and estimating a set of consistent parameters, we obtain the spectral index n_s, a small negative value of running α _s and tensor to scalar ratio r, which these reveal a degeneracy between deformed matter bounce scenario with RVM-DE and inflationary cosmology.

Early Intervention Services for Early-Phase Psychosis - Centre for integrative psychiatry in Psychiatric Hospital "Sveti Ivan", Croatia.

PubMed

Matić, Katarina; Gereš, Natko; Gerlach, Josefina; Prskalo-Čule, Diana; Zadravec Vrbanc, Tihana; Lovretić, Vanja; Librenjak, Dina; Vuk Pisk, Sandra; Ivezić, Ena; Šimunović Filipčić, Ivona; Jeleč, Vjekoslav; Filipčić, Igor

2018-06-01

There is a growing body of evidence suggesting that early and effective management in the critical early years of schizophrenia can improve long-term outcomes. The objective of this study was to evaluate time to relapse of the patients with early-phase psychosis treated in the Centre for integrative psychiatry (CIP). We performed a retrospective cohort study on the sample of 373 early-phase psychosis patients admitted to Psychiatric Hospital "Sveti Ivan", Zagreb Croatia: from January 1, 2015 to December 31, 2017. The primary outcome was time to relapse. Patients who were admitted to group psychotherapeutic program after the end of acute treatment had 70% lower hazard for relapse (HR=0.30; 95% CI 0.16-0.58). Patients who were included first in the psychotherapeutic program and then treated and controlled in the daily hospital had 74% lower hazard for relapse (HR=0.26; 95% CI 0.10-0.67). In early-phase psychosis, integrative early intervention service has relevant beneficial effects compare to treatment as usual. These results justified the implementation of multimodal early intervention services in treatment of patients with early-phase psychosis.

Thyroidectomy: post-operative care and common complications.

PubMed

Furtado, L

Any surgical procedure involves risks. Thyroid surgery can cause potentially fatal complications during the early post-operative phase. It is essential that nurses have the knowledge and skills to detect early signs and symptoms of potential complications and take appropriate action. Early detection and rapid response are key to maintaining patient safety and minimising harm.

S-phase Synchronization Facilitates the Early Progression of Induced-Cardiomyocyte Reprogramming through Enhanced Cell-Cycle Exit.

PubMed

Bektik, Emre; Dennis, Adrienne; Pawlowski, Gary; Zhou, Chen; Maleski, Danielle; Takahashi, Satoru; Laurita, Kenneth R; Deschênes, Isabelle; Fu, Ji-Dong

2018-05-04

Direct reprogramming of fibroblasts into induced cardiomyocytes (iCMs) holds a great promise for regenerative medicine and has been studied in several major directions. However, cell-cycle regulation, a fundamental biological process, has not been investigated during iCM-reprogramming. Here, our time-lapse imaging on iCMs, reprogrammed by Gata4, Mef2c, and Tbx5 (GMT) monocistronic retroviruses, revealed that iCM-reprogramming was majorly initiated at late-G1- or S-phase and nearly half of GMT-reprogrammed iCMs divided soon after reprogramming. iCMs exited cell cycle along the process of reprogramming with decreased percentage of 5-ethynyl-20-deoxyuridine (EdU)⁺/α-myosin heavy chain (αMHC)-GFP⁺ cells. S-phase synchronization post-GMT-infection could enhance cell-cycle exit of reprogrammed iCMs and yield more GFP high iCMs, which achieved an advanced reprogramming with more expression of cardiac genes than GFP low cells. However, S-phase synchronization did not enhance the reprogramming with a polycistronic-viral vector, in which cell-cycle exit had been accelerated. In conclusion, post-infection synchronization of S-phase facilitated the early progression of GMT-reprogramming through a mechanism of enhanced cell-cycle exit.

Synchronization with competing visual and auditory rhythms: bouncing ball meets metronome.

PubMed

Hove, Michael J; Iversen, John R; Zhang, Allen; Repp, Bruno H

2013-07-01

Synchronization of finger taps with periodically flashing visual stimuli is known to be much more variable than synchronization with an auditory metronome. When one of these rhythms is the synchronization target and the other serves as a distracter at various temporal offsets, strong auditory dominance is observed. However, it has recently been shown that visuomotor synchronization improves substantially with moving stimuli such as a continuously bouncing ball. The present study pitted a bouncing ball against an auditory metronome in a target-distracter synchronization paradigm, with the participants being auditory experts (musicians) and visual experts (video gamers and ball players). Synchronization was still less variable with auditory than with visual target stimuli in both groups. For musicians, auditory stimuli tended to be more distracting than visual stimuli, whereas the opposite was the case for the visual experts. Overall, there was no main effect of distracter modality. Thus, a distracting spatiotemporal visual rhythm can be as effective as a distracting auditory rhythm in its capacity to perturb synchronous movement, but its effectiveness also depends on modality-specific expertise.

Dynamics of anisotropies close to a cosmological bounce in quantum gravity

NASA Astrophysics Data System (ADS)

de Cesare, Marco; Oriti, Daniele; Pithis, Andreas G. A.; Sakellariadou, Mairi

2018-01-01

We study the dynamics of perturbations representing deviations from perfect isotropy in the context of the emergent cosmology obtained from the group field theory formalism for quantum gravity. Working in the mean field approximation of the group field theory formulation of the Lorentzian EPRL model, we derive the equations of motion for such perturbations to first order. We then study these equations around a specific simple isotropic background, characterised by the fundamental representation of SU(2) , and in the regime of the effective cosmological dynamics corresponding to the bouncing region replacing the classical singularity, well approximated by the free GFT dynamics. In this particular example, we identify a region in the parameter space of the model such that perturbations can be large at the bounce but become negligible away from it, i.e. when the background enters the non-linear regime. We also study the departures from perfect isotropy by introducing specific quantities, such as the surface-area-to-volume ratio and the effective volume per quantum, which make them quantitative.

Changes in neural circuitry associated with depression at pre-clinical, pre-motor and early motor phases of Parkinson's disease.

PubMed

Borgonovo, Janina; Allende-Castro, Camilo; Laliena, Almudena; Guerrero, Néstor; Silva, Hernán; Concha, Miguel L

2017-02-01

Although Parkinson's Disease (PD) is mostly considered a motor disorder, it can present at early stages as a non-motor pathology. Among the non-motor clinical manifestations, depression shows a high prevalence and can be one of the first clinical signs to appear, even a decade before the onset of motor symptoms. Here, we review the evidence of early dysfunction in neural circuitry associated with depression in the context of PD, focusing on pre-clinical, pre-motor and early motor phases of the disease. In the pre-clinical phase, structural and functional changes in the substantia nigra, basal ganglia and limbic structures are already observed. Some of these changes are linked to motor compensation mechanisms while others correspond to pathological processes common to PD and depression and thus could underlie the appearance of depressive symptoms during the pre-motor phase. Studies of the early motor phase (less than five years post diagnosis) reveal an association between the extent of damage in different monoaminergic systems and the appearance of emotional disorders. We propose that the limbic loop of the basal ganglia and the lateral habenula play key roles in the early genesis of depression in PD. Alterations in the neural circuitry linked with emotional control might be sensitive markers of the ongoing neurodegenerative process and thus may serve to facilitate an early diagnosis of this disease. To take advantage of this, we need to improve the clinical criteria and develop biomarkers to identify depression, which could be used to determine individuals at risk to develop PD. Copyright © 2016 Elsevier Ltd. All rights reserved.

A measure of early physical functioning (EPF) post-stroke.

PubMed

Finch, Lois E; Higgins, Johanne; Wood-Dauphinee, Sharon; Mayo, Nancy E

2008-07-01

To develop a comprehensive measure of Early Physical Functioning (EPF) post-stroke quantified through Rasch analysis and conceptualized using the International Classification of Functioning Disability and Health (ICF). An observational cohort study. A cohort of 262 subjects (mean age 71.6 (standard deviation 12.5) years) hospitalized post-acute stroke. Functional assessments were made within 3 days of stroke with items from valid and reliable indices commonly utilized to evaluate stroke survivors. Information on important variables was also collected. Principal component and Rasch analysis confirmed the factor structure, and dimensionality of the measure. Rasch analysis combined items across ICF components to develop the measure. Items were deleted iteratively, those retained fit the model and were related to the construct; reliability and validity were assessed. A 38-item unidimensional measure of the EPF met all Rasch model requirements. The item difficulty matched the person ability (mean person measure: -0.31; standard error 0.37 logits), reliability of the person-item-hierarchy was excellent at 0.97. Initial validity was adequate. The 38-item EPF measure was developed. It expands the range of assessment post acute stroke; it covers a broad spectrum of difficulty with good initial psychometric properties that, once revalidated, can assist in planning and evaluating early interventions.

Effects of human running cadence and experimental validation of the bouncing ball model

NASA Astrophysics Data System (ADS)

Bencsik, László; Zelei, Ambrus

2017-05-01

The biomechanical analysis of human running is a complex problem, because of the large number of parameters and degrees of freedom. However, simplified models can be constructed, which are usually characterized by some fundamental parameters, like step length, foot strike pattern and cadence. The bouncing ball model of human running is analysed theoretically and experimentally in this work. It is a minimally complex dynamic model when the aim is to estimate the energy cost of running and the tendency of ground-foot impact intensity as a function of cadence. The model shows that cadence has a direct effect on energy efficiency of running and ground-foot impact intensity. Furthermore, it shows that higher cadence implies lower risk of injury and better energy efficiency. An experimental data collection of 121 amateur runners is presented. The experimental results validate the model and provides information about the walk-to-run transition speed and the typical development of cadence and grounded phase ratio in different running speed ranges.

Reversed structures and bounce structures: are they recognizable? Are they real?

NASA Astrophysics Data System (ADS)

Means, W. D.

1999-08-01

This note poses two related questions about structural evolution in rocks. How easy is it to recognize structural features that have reversed their sense of development over time? Are there circumstances in rock deformation where early intensification of structure sows the seeds for a later, more or less inevitable, diminution of intensity? It is suggested, as a partial answer to the first question, that there is an irreversibility principle inherent to most structural development, such that even if bulk strain is reversed, the structural changes that accompanied `forward' structural development will not be completely reversed when the strain is reversed. Where this principle applies, it should always be possible to recognize structural reversals, by sufficiently close observation of the final state. It is suggested, as a partial answer to the second question, that where energy is stored by forward structural changes, this energy can often be expected to drive further structural changes, and these further changes may sometimes cause the original structure to `bounce' back to a less intense state. These questions may have some bearing on developing a firmer basis for kinematic analysis, and for understanding overprinting structures in orogens.

The role of sleep in adolescents' daily stress recovery: Negative affect spillover and positive affect bounce-back effects.

PubMed

Chue, Amanda E; Gunthert, Kathleen C; Kim, Rebecca W; Alfano, Candice A; Ruggiero, Aria R

2018-07-01

The present study examined the role of sleep in daily affective stress recovery processes in adolescents. Eighty-nine American adolescents recorded their emotions and stress through daily surveys and sleep with Fitbit devices for two weeks. Results show that objectively measured sleep (sleep onset latency and sleep debt) moderated negative affective responses to previous-day stress, such that stress-related negative affect spillover effects became more pronounced as amount of sleep decreased. Total sleep time and sleep debt moderated cross-day positive affect "bounce-back" effects. With more sleep, morning positive affect on days following high stress tended to bounce back to the levels that were common following low stress days. Conversely, if sleep was short following high stress days, positive affect remained low the next morning. No evidence for subjective sleep quality as a moderator of spillover/bounce-back effects was found. This research suggests that sleep quantity could relate to overnight affective stress recovery. Copyright © 2018. Published by Elsevier Ltd.

Salem 98: A post-plume phase, federal participation exercise

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Salem 98 was the largest nuclear power plant post-plume phase exercise since the 1993 FRMAC-93 exercise at the Fort Calhoun Nuclear Power Plant in Nebraska. Salem 98 was a 3 Day exercise, held on May 5--7, 1998, involving participation by the States of New Jersey and Delaware and associated State and county agencies. Public Service Electric and Gas was the host utility and Salem County the host county. Federal participation included the Nuclear Regulatory Commission, Federal Emergency Management Agency, Department of Energy, Environmental Protection Agency, US department of Agriculture and Department of Health and Human Services. In addition, the Americanmore » Nuclear Insurers participated, adding a dimension to the exercise not experienced often enough. This was a stand-alone post-plume phase exercise, which took place 2 months after the evaluated plume phase exercise held on March 3, 1998, also including participation by various Federal agencies. This exercise demonstrated the positive working relationship among utility, State, county, and Federal responders in response to a postulated major nuclear power plant emergency with significant offsite consequences.« less

Metabolic changes in concussed American football players during the acute and chronic post-injury phases

PubMed Central

2011-01-01

Background Despite negative neuroimaging findings many athletes display neurophysiological alterations and post-concussion symptoms that may be attributable to neurometabolic alterations. Methods The present study investigated the effects of sports concussion on brain metabolism using 1H-MR Spectroscopy by comparing a group of 10 non-concussed athletes with a group of 10 concussed athletes of the same age (mean: 22.5 years) and education (mean: 16 years) within both the acute and chronic post-injury phases. All athletes were scanned 1-6 days post-concussion and again 6-months later in a 3T Siemens MRI. Results Concussed athletes demonstrated neurometabolic impairment in prefrontal and motor (M1) cortices in the acute phase where NAA:Cr levels remained depressed relative to controls. There was some recovery observed in the chronic phase where Glu:Cr levels returned to those of control athletes; however, there was a pathological increase of m-I:Cr levels in M1 that was only present in the chronic phase. Conclusions These results confirm cortical neurometabolic changes in the acute post-concussion phase as well as recovery and continued metabolic abnormalities in the chronic phase. The results indicate that complex pathophysiological processes differ depending on the post-injury phase and the neurometabolite in question. PMID:21861906

An Experimental Study of the Effect of Viscosity on Bouncing Soap Droplets onto a Horizontal Soap Film

NASA Astrophysics Data System (ADS)

Gunter, Amy-Lee; Ng, Hoi Dick

2012-11-01

This experimental study aims to investigate the phenomenon of a bouncing soap droplet on a horizontal soap film, and how this behavior is affected by variations in the glycerol content of the solution for both the droplet and film. Direct visualization of the bouncing dynamics using high-speed photography allows determination of droplet size and rebound height as the viscosity is varied. In addition, the upper and lower limits of the mixture composition at which the viscosity of the fluid prevents the droplet from bouncing are determined. A thorough examination of this fluid trampoline was recently conducted by Gilet and Bush, the focus of which was to compare the effect of vibration in the soap film [T. Gilet and J.W.M. Bush, J. Fluid Mech. 625: 167-203, 2009]. A small amount of attention was given to the effect of viscosity changes in the droplet and film, and this work aims to expand on those findings. This work is supported by the Natural Sciences and Engineering Research Council of Canada (NSERC).

Particle bounce in a personal cascade impactor: a field evaluation.

PubMed

Hinds, W C; Liu, W C; Froines, J R

1985-09-01

The collection characteristics of five types of substrates (collection surfaces) used in personal cascade impactors were evaluated for particle bounce in the laboratory with lead dioxide dust, and in the field with brass pouring fume and brass grinding dust. The substrates tested were uncoated stainless steel, silicon grease-coated stainless steel, oil-saturated Millipore membrane filter, oil-saturated Teflon membrane filter and oil-saturated sintered stainless steel. The use of coated and uncoated stainless steel plates to collect lead dioxide dust produced no difference in measured mass median diameter (MMD); however, with brass grinding dust, there was a 50% decrease in measured MMD when uncoated stainless steel substrates were used, as compared with coated stainless steel substrates. Oil-saturated Millipore membrane surfaces gave consistently lower MMDs than coated stainless steel surfaces. Coated and uncoated stainless steel gave similar MMDs when used to sample brass pouring fume. Oil-saturated Teflon membrane and oil-saturated sintered metal, surfaces for which the collection efficiency is presumed to be independent of the particle loading, gave MMDs similar to those measured for grease-coated stainless steel. The implications of these comparisons are discussed. It is concluded that bounce characteristics are strongly dependent on aerosol material and the suitability of collection surfaces needs to be determined by field evaluation.

Heat exchange between a bouncing drop and a superhydrophobic substrate

PubMed Central

Shiri, Samira; Bird, James C.

2017-01-01

The ability to enhance or limit heat transfer between a surface and impacting drops is important in applications ranging from industrial spray cooling to the thermal regulation of animals in cold rain. When these surfaces are micro/nanotextured and hydrophobic, or superhydrophobic, an impacting drop can spread and recoil over trapped air pockets so quickly that it can completely bounce off the surface. It is expected that this short contact time limits heat transfer; however, the amount of heat exchanged and precise role of various parameters, such as the drop size, are unknown. Here, we demonstrate that the amount of heat exchanged between a millimeter-sized water drop and a superhydrophobic surface will be orders of magnitude less when the drop bounces than when it sticks. Through a combination of experiments and theory, we show that the heat transfer process on superhydrophobic surfaces is independent of the trapped gas. Instead, we find that, for a given spreading factor, the small fraction of heat transferred is controlled by two dimensionless groupings of physical parameters: one that relates the thermal properties of the drop and bulk substrate and the other that characterizes the relative thermal, inertial, and capillary dynamics of the drop. PMID:28630306

Evaluation of measles-rubella vaccination for mothers in early puerperal phase.

PubMed

Hisano, Michi; Kato, Tatsuo; Inoue, Eisuke; Sago, Haruhiko; Yamaguchi, Koushi

2016-02-24

The postpartum period is an ideal opportunity to vaccinate mothers with inadequate immunity to vaccine-preventable diseases including measles and rubella. A prospective study of measles-rubella (MR) vaccination in the early puerperal phase was conducted in 171 mothers, who had insufficient antibody titers when screened for immunity to measles (≤ 1:4 on the neutralization test [NT]) or rubella (≤ 1:16 on the hemagglutination inhibition [HI] test) during pregnancy. To evaluate the efficacy of MR vaccination in the postpartum period, we determined their post-vaccination antibody titers and immune responses to vaccination, and investigated the association between these and their prolactin (PRL) levels and Th1/Th2 ratios at the time of vaccination. We also examined the passage of viral RNA and antigen into breast milk. Of the 169 participants who completed the study schedule, 117 and 101 had low antibody titers against measles and rubella, respectively. In the measles-seronegative group, the antibody-positive rate was 87% on the NT assay, and the NT geometric mean antibody titer was 11.4 (95% confidence interval [CI], 10.0-13.0). In the rubella-seronegative group, the antibody-positive rate was 88% on the HI test assay, and the HI geometric mean antibody titer was 64.0 (95% CI, 53.9-76.0). There was no association between the post-vaccination antibody titers and the PRL levels or Th1/Th2 ratios at the time of vaccination. In the rubella-seronegative group, subjects with higher Th1/Th2 ratios showed higher rates of responsiveness than those with lower ratios (P=0.045). Although measles virus RNA was isolated from the breast milk of two vaccinated mothers, breastfeeding was not associated with clinical disease in any infants. MR vaccination in the early puerperal phase is considered an effective way to prevent the diseases, regardless of the mother's immunological status and hormonal milieu. Copyright © 2016 Elsevier Ltd. All rights reserved.

Viability of the matter bounce scenario in F(T) gravity and Loop Quantum Cosmology for general potentials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haro, Jaume; Amorós, Jaume, E-mail: jaime.haro@upc.edu, E-mail: jaume.amoros@upc.edu

2014-12-01

We consider the matter bounce scenario in F(T) gravity and Loop Quantum Cosmology (LQC) for phenomenological potentials that at early times provide a nearly matter dominated Universe in the contracting phase, having a reheating mechanism in the expanding or contracting phase, i.e., being able to release the energy of the scalar field creating particles that thermalize in order to match with the hot Friedmann Universe, and finally at late times leading to the current cosmic acceleration. For these potentials, numerically solving the dynamical perturbation equations we have seen that, for the particular F(T) model that we will name teleparallel versionmore » of LQC, and whose modified Friedmann equation coincides with the corresponding one in holonomy corrected LQC when one deals with the flat Friedmann-Lemaître-Robertson-Walker (FLRW) geometry, the corresponding equations obtained from the well-know perturbed equations in F(T) gravity lead to theoretical results that fit well with current observational data. More precisely, in this teleparallel version of LQC there is a set of solutions which leads to theoretical results that match correctly with last BICEP2 data, and there is another set whose theoretical results fit well with Planck's experimental data. On the other hand, in the standard holonomy corrected LQC, using the perturbed equations obtained replacing the Ashtekar connection by a suitable sinus function and inserting some counter-terms in order to preserve the algebra of constrains, the theoretical value of the tensor/scalar ratio is smaller than in the teleparallel version, which means that there is always a set of solutions that matches with Planck's data, but for some potentials BICEP2 experimental results disfavours holonomy corrected LQC.« less

Early Diagnosis and Intervention Strategies for Post-Traumatic Heterotopic Ossification in Severely Injured Extremities

DTIC Science & Technology

2016-12-01

1 Award Number: W81XWH-12-2-0118 TITLE: Early Diagnosis and Intervention Strategies for Post -Traumatic Heterotopic Ossification in Severely...December 2016 TYPE OF REPORT: Final PREPARED FOR: U.S. Army Medical Research and Materiel Command Fort Detrick, Maryland 21702-5012 DISTRIBUTION...COVERED 30Sep2012 - 29Sep2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Early Diagnosis and Intervention Strategies for Post -Traumatic Heterotopic

Bouncing-to-Merging Transition in Drop Impact on Liquid Film: Role of Liquid Viscosity.

PubMed

Tang, Xiaoyu; Saha, Abhishek; Law, Chung K; Sun, Chao

2018-02-27

When a drop impacts on a liquid surface, it can either bounce back or merge with the surface. The outcome affects many industrial processes, in which merging is preferred in spray coating to generate a uniform layer and bouncing is desired in internal combustion engines to prevent accumulation of the fuel drop on the wall. Thus, a good understanding of how to control the impact outcome is highly demanded to optimize the performance. For a given liquid, a regime diagram of bouncing and merging outcomes can be mapped in the space of Weber number (ratio of impact inertia and surface tension) versus film thickness. In addition, recognizing that the liquid viscosity is a fundamental fluid property that critically affects the impact outcome through viscous dissipation of the impact momentum, here we investigate liquids with a wide range of viscosity from 0.7 to 100 cSt, to assess its effect on the regime diagram. Results show that while the regime diagram maintains its general structure, the merging regime becomes smaller for more viscous liquids and the retraction merging regime disappears when the viscosity is very high. The viscous effects are modeled and subsequently the mathematical relations for the transition boundaries are proposed which agree well with the experiments. The new expressions account for all the liquid properties and impact conditions, thus providing a powerful tool to predict and manipulate the outcome when a drop impacts on a liquid film.

Phase III Early Restoration Meeting | NOAA Gulf Spill Restoration

Science.gov Websites

Louisiana Mississippi Texas Region-wide Open Ocean Data Media & News Publications Press Releases Story programmatic approach to early restoration planning for Phase III and future early restoration plans. Open

Phase III Early Restoration Meeting - Pensacola, FL (rescheduled) | NOAA

Science.gov Websites

Restoration Areas Alabama Florida Louisiana Mississippi Texas Region-wide Open Ocean Data Media & News programmatic approach to early restoration planning for Phase III and future early restoration plans. Open

Early versus delayed post-operative bathing or showering to prevent wound complications.

PubMed

Toon, Clare D; Sinha, Sidhartha; Davidson, Brian R; Gurusamy, Kurinchi Selvan

2015-07-23

Many people undergo surgical operations during their life-time, which result in surgical wounds. After an operation the incision is closed using stiches, staples, steri-strips or an adhesive glue. Usually, towards the end of the surgical procedure and before the patient leaves the operating theatre, the surgeon covers the closed surgical wound using gauze and adhesive tape or an adhesive tape containing a pad (a wound dressing) that covers the surgical wound. There is currently no guidance about when the wound can be made wet by post-operative bathing or showering. Early bathing may encourage early mobilisation of the patient, which is good after most types of operation. Avoiding post-operative bathing or showering for two to three days may result in accumulation of sweat and dirt on the body. Conversely, early washing of the surgical wound may have an adverse effect on healing, for example by irritating or macerating the wound, and disturbing the healing environment. To compare the benefits (such as potential improvements to quality of life) and harms (potentially increased wound-related morbidity) of early post-operative bathing or showering (i.e. within 48 hours after surgery, the period during which epithelialisation of the wound occurs) compared with delayed post-operative bathing or showering (i.e. no bathing or showering for over 48 hours after surgery) in patients with closed surgical wounds. We searched The Cochrane Wounds Group Specialised Register (30th June 2015); The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); The Database of Abstracts of Reviews of Effects (DARE) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; EBSCO CINAHL; the metaRegister of Controlled Trials (mRCT) and the International Clinical Trials Registry Platform (ICTRP). We considered all randomised trials conducted in patients who had undergone any surgical procedure and had surgical closure of

Early versus delayed post-operative bathing or showering to prevent wound complications.

PubMed

Toon, Clare D; Sinha, Sidhartha; Davidson, Brian R; Gurusamy, Kurinchi Selvan

2013-10-12

Many people undergo surgical operations during their life-time, which result in surgical wounds. After an operation the incision is closed using stiches, staples, steri-strips or an adhesive glue. Usually, towards the end of the surgical procedure and before the patient leaves the operating theatre, the surgeon covers the closed surgical wound using gauze and adhesive tape or an adhesive tape containing a pad (a wound dressing) that covers the surgical wound. There is currently no guidance about when the wound can be made wet by post-operative bathing or showering. Early bathing may encourage early mobilisation of the patient, which is good after most types of operation. Avoiding post-operative bathing or showering for two to three days may result in accumulation of sweat and dirt on the body. Conversely, early washing of the surgical wound may have an adverse effect on healing, for example by irritating or macerating the wound, and disturbing the healing environment. To compare the benefits (such as potential improvements to quality of life) and harms (potentially increased wound-related morbidity) of early post-operative bathing or showering (i.e. within 48 hours after surgery, the period during which epithelialisation of the wound occurs) compared with delayed post-operative bathing or showering (i.e. no bathing or showering for over 48 hours after surgery) in patients with closed surgical wounds. We searched The Cochrane Wounds Group Specialised Register;The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); The Database of Abstracts of Reviews of Effects (DARE) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; EBSCO CINAHL; the metaRegister of Controlled Trials (mRCT) and the International Clinical Trials Registry Platform (ICTRP). We considered all randomised trials conducted in patients who had undergone any surgical procedure and had surgical closure of their wounds

Arrows of time in the bouncing universes of the no-boundary quantum state

NASA Astrophysics Data System (ADS)

Hartle, James; Hertog, Thomas

2012-05-01

We derive the arrows of time of our universe that follow from the no-boundary theory of its quantum state (NBWF) in a minisuperspace model. Arrows of time are viewed four-dimensionally as properties of the four-dimensional Lorentzian histories of the universe. Probabilities for these histories are predicted by the NBWF. For histories with a regular “bounce” at a minimum radius fluctuations are small at the bounce and grow in the direction of expansion on either side. For recollapsing classical histories with big bang and big crunch singularities the fluctuations are small near one singularity and grow through the expansion and recontraction to the other singularity. The arrow of time defined by the growth in fluctuations thus points in one direction over the whole of a recollapsing spacetime but is bidirectional in a bouncing spacetime. We argue that the electromagnetic, thermodynamic, and psychological arrows of time are aligned with the fluctuation arrow. The implications of a bidirectional arrow of time for causality are discussed.

Post-conditioning preserves glycolytic ATP during early reperfusion: a survival mechanism for the reperfused heart.

PubMed

Correa, Francisco; García, Noemí; Gallardo-Pérez, Juan; Carreno-Fuentes, Liliana; Rodríguez-Enríquez, Sara; Marín-Hernández, Alvaro; Zazueta, Cecilia

2008-01-01

Glycolytic activity during the transition period from anaerobic to aerobic metabolism has been demonstrated to be critical for heart recovery in isolated reperfused hearts. The purpose of this work was to investigate the relevance of the glycolytic pathway in preserving the cardiac function of post-conditioned hearts. The activation of the glycolytic pathway in post-conditioned hearts was evaluated by measuring GLUT-4 insertion, glucose consumption and lactate production. Iodoacetic acid and 2-deoxy-D-glucose were administrated to the working hearts to evaluate the effect of glycolytic inhibition in the post-conditioning protective effect. Post-conditioning maneuvers applied to isolated rat hearts, after prolonged ischemia and before reperfusion, promoted recovery of cardiac mechanical function with sustained increase of GLUT-4 translocation and activation of the glycolytic pathway during ischemia and early reperfusion. Iodoacetate inhibited the protective effect of post-conditioning, without affecting the mitochondrial oxidative capacity. Glycolysis contribution to maintain mechanical function at early reperfusion was observed in post-conditioned hearts perfused with 2-deoxy-D-glucose and in hearts in which iodoacetate was administered only during reperfusion. It is concluded that in the post-conditioned heart, a functional compartmentation of anaerobic energy metabolism, at early reperfusion, plays a significant role in cardiac protection against reperfusion damage. Copyright 2008 S. Karger AG, Basel.

Diatom diet selectivity by early post-larval abalone Haliotis diversicolor supertexta under hatchery conditions

NASA Astrophysics Data System (ADS)

Zhang, Yuyu; Gao, Yahui; Liang, Junrong; Chen, Changping; Zhao, Donghai; Li, Xuesong; Li, Yang; Wu, Wenzhong

2010-11-01

Benthic diatoms constitute the primary diet of abalone during their early stages of development. To evaluate the dietary preferences of early post-larval abalone, Haliotis diversicolor supertexta, we analyzed the gut contents of post-larvae that settled on diatom films. We compared the abundance and species diversity of diatom assemblages in the gut to those of the epiphytic diatom assemblages on the attachment films, and identified 40 benthic diatom species in the gut contents of post-larvae 12 to 24 d after settlement. The most abundant taxa in the gut contents were Navicula spp., Amphora copulate, and Amphora coffeaeformis. Navicula spp. accounted for 64.0% of the cell density. In the attachment films, we identified 110 diatom species belonging to 38 genera. Pennate diatoms were the dominant members including the species Amphiprora alata, Cocconeis placentula var. euglypta, Cylindrotheca closterium, Navicula sp. 2, and A. coffeaeformis. Nano-diatoms (<20 μm in length) accounted for a considerable proportion of the total species number and cell density of the diatom assemblages in the gut contents and on the films. This suggests that nano-diatoms are important to the efficient production of abalone seed. The difference of the composition and abundance of diatoms between in the guts and on the biofilms suggests that early post-larval grazing was selective. An early post-larval abalone preferred nano-diatoms and the genera Navicula and Amphora during the month after settlement.

Metacognition in Early Phase Psychosis: Toward Understanding Neural Substrates

PubMed Central

Vohs, Jenifer L.; Hummer, Tom A.; Yung, Matthew G.; Francis, Michael M.; Lysaker, Paul H.; Breier, Alan

2015-01-01

Individuals in the early phases of psychotic illness have disturbed metacognitive capacity, which has been linked to a number of poor outcomes. Little is known, however, about the neural systems associated with metacognition in this population. The purpose of this study was to elucidate the neuroanatomical correlates of metacognition. We anticipated that higher levels of metacognition may be dependent upon gray matter density (GMD) of regions within the prefrontal cortex. Examining whole-brain structure in 25 individuals with early phase psychosis, we found positive correlations between increased medial prefrontal cortex and ventral striatum GMD and higher metacognition. These findings represent an important step in understanding the path through which the biological correlates of psychotic illness may culminate into poor metacognition and, ultimately, disrupted functioning. Such a path will serve to validate and promote metacognition as a viable treatment target in early phase psychosis. PMID:26132568

Architecture Study on Telemetry Coverage for Immediate Post-Separation Phase

NASA Technical Reports Server (NTRS)

Cheung, Kar-Ming; Lee, Charles H.; Kellogg, Kent H.; Stocklin, Frank J.; Zillig, David J.; Fielhauer, Karl B.

2008-01-01

This paper presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. This study is a collaboration effort between Jet Propulsion Laboratory (JPL), Goddard Space Flight Center (GSFC), and Applied Physics Laboratory (APL). After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed.This paper presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. This study is a collaboration effort between Jet Propulsion Laboratory (JPL), Goddard Space Flight Center (GSFC), and Applied Physics Laboratory (APL). After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed. The main results of this study are as follows: 1) At low altitude (< 10000 km) when most post-separation critical operations are executed, Earth-based network

Small Business Innovation Research, Post-Phase II Opportunity Assessment

NASA Technical Reports Server (NTRS)

Nguyen, Hung D.; Steele, Gynelle C.

2015-01-01

This report outlines current Small Business Innovation Research (SBIR) Post-Phase II opportunity contract award results for the SBIR technology program from 2007 to 2011 for NASA's Aeronautics Research Mission Directorate (ARMD), Human Exploration and Operations Mission Directorate (HEOMD), Science Mission Directorate (SMD), and Space Technology Mission Directorate (STMD). The report provides guidelines for incorporating SBIR technology into NASA programs and projects and provides a quantitative overview of the post-Phase II award patterns that correspond with each mission directorate at NASA Glenn Research Center (GRC). In recent years, one of NASA's goals has been to not only transfer SBIR technologies to commercial industries, but to ensure that NASA mission directorates incorporate SBIR technologies into their program and project activities. Before incorporating technologies into MD programs, it is important to understand each mission directorate structure because each directorate has different objectives and needs. The directorate program structures follow.

Nonsingular, big-bounce cosmology from spinor-torsion coupling

NASA Astrophysics Data System (ADS)

Popławski, Nikodem

2012-05-01

The Einstein-Cartan-Sciama-Kibble theory of gravity removes the constraint of general relativity that the affine connection be symmetric by regarding its antisymmetric part, the torsion tensor, as a dynamical variable. The minimal coupling between the torsion tensor and Dirac spinors generates a spin-spin interaction which is significant in fermionic matter at extremely high densities. We show that such an interaction averts the unphysical big-bang singularity, replacing it with a cusp-like bounce at a finite minimum scale factor, before which the Universe was contracting. This scenario also explains why the present Universe at largest scales appears spatially flat, homogeneous and isotropic.

Study of the dynamic properties and effects of temperature using a spring model for the bouncing ball

NASA Astrophysics Data System (ADS)

Wadhwa, Ajay

2013-05-01

We studied the motion of a bouncing ball by representing it through an equivalent mass-spring system executing damped harmonic oscillations. We represented the elasticity of the system through the spring constant ‘k’ and the viscous damping effect, causing loss of energy, through damping constant ‘c’. By including these two factors we formed a differential equation for the equivalent mass-spring system of the bouncing ball. This equation was then solved to study the elastic and dynamic properties of its motion by expressing them in terms of experimentally measurable physical quantities such as contact time, coefficient of restitution, etc. We used our analysis for different types of ball material: rubber (lawn-tennis ball, super ball, soccer ball and squash ball) and plastic (table-tennis ball) at room temperature. Since the effect of temperature on the bounce of a squash ball is significant, we studied the temperature dependence of its elastic properties. The experiments were performed using audio and surface-temperature sensors interfaced with a computer through a USB port. The work presented here is suitable for undergraduate laboratories. It particularly emphasizes the use of computer interfacing for conducting conventional physics experiments.

Early post-interventional sonographic evaluation of prostatic artery embolization. A promising role for contrast-enhanced ultrasonography (CEUS).

PubMed

Moschouris, Hippocrates; Stamatiou, Konstantinos; Kalokairinou Motogna, Mariana; Vrakas, Spyros; Kiltenis, Michail; Kladis-Kalentzis, Konstantinos; Tsavdaroglou, Avraam; Papadogeorgopoulos, Nikolaos; Marmaridou, Kyriaki; Malagari, Katerina

2018-05-02

To assess the feasibility, findings and potential value of early post-interventional, contrast-enhanced ultrasonographic (CEUS) study of prostate artery embolization (PAE). Fourteen patients treated with PAE for symptomatic benign prostatic hyperplasia were prospectively included in the study. Sonographic evaluation of the prostate included: 1) baseline transabdominal and transrectal CEUS (ta-CEUS and tr-CEUS, respectively) 1-3 days prior to PAE; 2) early post PAE CEUS, with ta-CEUS immediately post PAE and tr-CEUS 3 days post PAE; and 3) follow-up with ta-CEUS and tr-CEUS 3 months post PAE. A brief unenhanced US study preceded each CEUS. Post-therapeutic changes in size, echogenicity and enhancement of the prostate were recorded and were correlated with clinical outcomes. PAE resulted in clinical success in 11/14 patients (78.5%). All sonographic studies were technically adequate, with the exception of ta-CEUS immediately post PAE in 2/14 (14.2%) patients. CEUS studies immediately post PAE and 3 days post PAE showed non-enhancing, welldefined infarctions of the prostate in 10/14 patients (71.4%). There was a strong correlation between ta-CEUS immediately post PAE and tr-CEUS 3 days post PAE regarding the measurements of prostatic infarctions (r =0.98, p< 0.01). The presence of infarctions on early post PAE CEUS was associated with clinical success (p=0.01) and their extent correlated with the degree of prostate shrinkage on 3-month follow-up (r=0.84, p<0.05). The 3 cases of failed PAE showed no infarctions and no prostate shrinkage. Early post-interventional CEUS of PAE is feasible and may have clinical and prognostic value.

Phase state of ambient aerosol linked with water uptake and chemical aging in the southeastern US

DOE PAGES

Pajunoja, Aki; Hu, Weiwei; Leong, Yu J.; ...

2016-09-09

During the summer 2013 Southern Aerosol and Oxidant Study (SOAS) field campaign in a rural site in the southeastern United States, the effect of hygroscopicity and composition on the phase state of atmospheric aerosol particles dominated by the organic fraction was studied. The analysis is based on hygroscopicity measurements by a Hygroscopic Tandem Differential Mobility Analyzer (HTDMA), physical phase state investigations by an Aerosol Bounce Instrument (ABI) and composition measurements using a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). To study the effect of atmospheric aging on these properties, an OH-radical oxidation flow reactor (OFR) was used to simulate longer atmosphericmore » aging times of up to 3 weeks. Hygroscopicity and bounce behavior of the particles had a clear relationship showing higher bounce at elevated relative humidity (RH) values for less hygroscopic particles, which agrees well with earlier laboratory studies. Additional OH oxidation of the aerosol particles in the OFR increased the O:C and the hygroscopicity resulting in liquefying of the particles at lower RH values. At the highest OH exposures, the inorganic fraction starts to dominate the bounce process due to production of inorganics and concurrent loss of organics in the OFR. Our results indicate that at typical ambient RH and temperature, organic-dominated particles stay mostly liquid in the atmospheric conditions in the southeastern US, but they often turn semisolid when dried below ~50 % RH in the sampling inlets. Furthermore, while the liquid phase state suggests solution behavior and equilibrium partitioning for the SOA particles in ambient air, the possible phase change in the drying process highlights the importance of thoroughly considered sampling techniques of SOA particles.« less

Phase state of ambient aerosol linked with water uptake and chemical aging in the southeastern US

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pajunoja, Aki; Hu, Weiwei; Leong, Yu J.

During the summer 2013 Southern Aerosol and Oxidant Study (SOAS) field campaign in a rural site in the southeastern United States, the effect of hygroscopicity and composition on the phase state of atmospheric aerosol particles dominated by the organic fraction was studied. The analysis is based on hygroscopicity measurements by a Hygroscopic Tandem Differential Mobility Analyzer (HTDMA), physical phase state investigations by an Aerosol Bounce Instrument (ABI) and composition measurements using a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). To study the effect of atmospheric aging on these properties, an OH-radical oxidation flow reactor (OFR) was used to simulate longer atmosphericmore » aging times of up to 3 weeks. Hygroscopicity and bounce behavior of the particles had a clear relationship showing higher bounce at elevated relative humidity (RH) values for less hygroscopic particles, which agrees well with earlier laboratory studies. Additional OH oxidation of the aerosol particles in the OFR increased the O:C and the hygroscopicity resulting in liquefying of the particles at lower RH values. At the highest OH exposures, the inorganic fraction starts to dominate the bounce process due to production of inorganics and concurrent loss of organics in the OFR. Our results indicate that at typical ambient RH and temperature, organic-dominated particles stay mostly liquid in the atmospheric conditions in the southeastern US, but they often turn semisolid when dried below ~50 % RH in the sampling inlets. Furthermore, while the liquid phase state suggests solution behavior and equilibrium partitioning for the SOA particles in ambient air, the possible phase change in the drying process highlights the importance of thoroughly considered sampling techniques of SOA particles.« less

Utility of Early Post-operative High Resolution Volumetric MR Imaging after Transsphenoidal Pituitary Tumor Surgery

PubMed Central

Patel, Kunal S.; Kazam, Jacob; Tsiouris, Apostolos J.; Anand, Vijay K.; Schwartz, Theodore H.

2014-01-01

Objective Controversy exists over the utility of early post-operative magnetic resonance imaging (MRI) after transsphenoidal pituitary surgery for macroadenomas. We investigate whether valuable information can be derived from current higher resolution scans. Methods Volumetric MRI scans were obtained in the early (<10 days) and late (>30 days) post-operative periods in a series of patients undergoing transsphenoidal pituitary surgery. The volume of the residual tumor, resection cavity, and corresponding visual field tests were recorded at each time point. Statistical analyses of changes in tumor volume and cavity size were calculated using the late MRI as the gold standard. Results 40 patients met the inclusion criteria. Pre-operative tumor volume averaged 8.8 cm3. Early postoperative assessment of average residual tumor volume (1.18 cm3) was quite accurate and did not differ statistically from late post-operative volume (1.23 cm3, p=.64), indicating the utility of early scans to measure residual tumor. Early scans were 100% sensitive and 91% specific for predicting ≥ 98% resection (p<.001, Fisher’s exact test). The average percent decrease in cavity volume from pre-operative MRI (tumor volume) to early post-operative imaging was 45% with decreases in all but 3 patients. There was no correlation between the size of the early cavity and the visual outcome. Conclusions Early high resolution volumetric MRI is valuable in determining the presence or absence of residual tumor. Cavity volume almost always decreases after surgery and a lack of decrease should alert the surgeon to possible persistent compression of the optic apparatus that may warrant re-operation. PMID:25045791

Hypocalcaemia following total thyroidectomy: early post-operative parathyroid hormone assay as a risk stratification and management tool.

PubMed

Islam, S; Al Maqbali, T; Howe, D; Campbell, J

2014-03-01

To develop a practical, efficient and predictive algorithm to manage potential or actual post-operative hypocalcaemia after complete thyroidectomy, using a single post-operative parathyroid hormone assay. This paper reports a prospective study of 59 patients who underwent total or completion thyroidectomy over a period of 24 months. Parathyroid hormone levels were checked post-operatively on the day of surgery, and all patients were evaluated for hypocalcaemia both clinically and biochemically with serial corrected calcium measurements. No patient with an early post-operative parathyroid hormone level of 23 ng/l or more (i.e. approximately twice the lower limit of the normal range) developed hypocalcaemia. All the patients who initially had post-operative hypocalcaemia but had an early parathyroid hormone level of 8 ng/l or more (i.e. approximately two-thirds of the lower limit of the normal range) had complete resolution of their hypocalcaemia within three months. Early post-operative parathyroid hormone measurement can reliably predict patients at risk of post-thyroidectomy hypocalcaemia, and predict those patients expected to recover from temporary hypocalcaemia. A suggested post-operative management algorithm is presented.

EXPERIMENTAL STUDIES ON PARTICLE IMPACTION AND BOUNCE: EFFECTS OF SUBSTRATE DESIGN AND MATERIAL. (R825270)

EPA Science Inventory

This paper presents an experimental investigation of the effects of impaction substrate designs and material in reducing particle bounce and reentrainment. Particle collection without coating by using combinations of different impaction substrate designs and surface materials was...

Minimal percentage of dose received by 90% of the urethra (%UD90) is the most significant predictor of PSA bounce in patients who underwent low-dose-rate brachytherapy (LDR-brachytherapy) for prostate cancer.

PubMed

Tanaka, Nobumichi; Asakawa, Isao; Fujimoto, Kiyohide; Anai, Satoshi; Hirayama, Akihide; Hasegawa, Masatoshi; Konishi, Noboru; Hirao, Yoshihiko

2012-09-14

To clarify the significant clinicopathological and postdosimetric parameters to predict PSA bounce in patients who underwent low-dose-rate brachytherapy (LDR-brachytherapy) for prostate cancer. We studied 200 consecutive patients who received LDR-brachytherapy between July 2004 and November 2008. Of them, 137 patients did not receive neoadjuvant or adjuvant androgen deprivation therapy. One hundred and forty-two patients were treated with LDR-brachytherapy alone, and 58 were treated with LDR-brachytherapy in combination with external beam radiation therapy. The cut-off value of PSA bounce was 0.1 ng/mL. The incidence, time, height, and duration of PSA bounce were investigated. Clinicopathological and postdosimetric parameters were evaluated to elucidate independent factors to predict PSA bounce in hormone-naïve patients who underwent LDR-brachytherapy alone. Fifty patients (25%) showed PSA bounce and 10 patients (5%) showed PSA failure. The median time, height, and duration of PSA bounce were 17 months, 0.29 ng/mL, and 7.0 months, respectively. In 103 hormone-naïve patients treated with LDR-brachytherapy alone, and univariate Cox proportional regression hazard model indicated that age and minimal percentage of the dose received by 30% and 90% of the urethra were independent predictors of PSA bounce. With a multivariate Cox proportional regression hazard model, minimal percentage of the dose received by 90% of the urethra was the most significant parameter of PSA bounce. Minimal percentage of the dose received by 90% of the urethra was the most significant predictor of PSA bounce in hormone-naïve patients treated with LDR-brachytherapy alone.

Shooting and bouncing rays - Calculating the RCS of an arbitrarily shaped cavity

NASA Technical Reports Server (NTRS)

Ling, Hao; Chou, Ri-Chee; Lee, Shung-Wu

1989-01-01

A ray-shooting approach is presented for calculating the interior radar cross section (RCS) from a partially open cavity. In the problem considered, a dense grid of rays is launched into the cavity through the opening. The rays bounce from the cavity walls based on the laws of geometrical optics and eventually exit the cavity via the aperture. The ray-bouncing method is based on tracking a large number of rays launched into the cavity through the opening and determining the geometrical optics field associated with each ray by taking into consideration (1) the geometrical divergence factor, (2) polarization, and (3) material loading of the cavity walls. A physical optics scheme is then applied to compute the backscattered field from the exit rays. This method is so simple in concept that there is virtually no restriction on the shape or material loading of the cavity. Numerical results obtained by this method are compared with those for the modal analysis for a circular cylinder terminated by a PEC plate. RCS results for an S-bend circular cylinder generated on the Cray X-MP supercomputer show significant RCS reduction. Some of the limitations and possible extensions of this technique are discussed.

Currents and Associated Electron Scattering and Bouncing Near the Diffusion Region at Earth's Magnetopause

NASA Technical Reports Server (NTRS)

Lavraud, B.; Zhang, Y. C.; Vernisse, Y.; Gershman, D. J.; Dorelli, J.; Cassak, P. A.; Dargent, J.; Pollock, C.; Giles, B.; Aunai, N.;

Enhancing the Bounce of a Ball

NASA Astrophysics Data System (ADS)

Cross, Rod

2010-10-01

In sports such as baseball, softball, golf, and tennis, a common objective is to hit the ball as fast or as far as possible. Another common objective is to hit the ball so that it spins as fast as possible, since the trajectory of the ball through the air is strongly affected by ball spin. In an attempt to enhance both the coefficient of restitution (COR) and the spin of a golf ball, I conducted several experiments to see what would happen when a 45-g, 42.8-mm diameter golf ball bounced on: (a) a 58-mm diameter, 103-g Super Ball®; (b) an 8-mm thick, 56-mm diameter circular disk of Super Ball material cut from a large Super Ball and glued to a 3.4-kg lead brick; and (c) a 3-mm thick sheet of rubber glued to a 3.4-kg lead brick. (See Fig. 1.)

Early post-natal neuroactive steroid manipulation modulates ondansetron effects on initial periods of alcohol consumption in rats.

PubMed

Bartolomé, Iris; Llidó, Anna; Darbra, Sònia; Pallarès, Marc

2018-06-21

Neuroactive steroids (NS) such as allopregnanolone are crucial for brain development and adult behaviour. Early post-natal alterations of NS by administering finasteride induce a decrease in the sensitivity to stimulant effects of low alcohol doses, an increase in alcohol consumption, and a decrease in ventrostriatal dopamine and serotonin levels. The aim of the present study is to observe if the effects of the 5HT3 receptor antagonist ondansetron on initial alcohol consumption are modulated by post-natal NS manipulation. For this purpose, allopregnanolone, finasteride, or vehicle was injected from day 5 to 9. In adulthood, a novel object preference test was carried out in order to detect a possible novelty-seeking pattern in our animals, which has been related to vulnerability to drug abuse. The subjects then had access to two bottles (alcohol or control solutions) one hour daily for two consecutive weeks. Ondansetron (0.01 mg/kg, 0.1 mg/kg or vehicle) was administered before the hour of consumption in the initial phase (days 1, 2, 3) of the procedure, and after prolonged alcohol intake (days 11, 12, 13). Results indicated that finasteride animals showed a higher preference to explore the new object, as well as a higher alcohol consumption than the rest of the groups. Moreover, 0.1 mg/kg of ondansetron decreased alcohol consumption, but only in the post-natal finasteride group, suggesting a possible increase in 5HT3 receptor sensitivity in these animals. In conclusion, NS manipulation in crucial stages of development, such as early post-natal periods, seems to play an important role on the effects of ondansetron on alcohol intake and in the vulnerability to develop drug use or abuse. Copyright © 2018. Published by Elsevier Inc.

Fluctuation-driven electroweak phase transition. [in early universe

NASA Technical Reports Server (NTRS)

Gleiser, Marcelo; Kolb, Edward W.

1992-01-01

We examine the dynamics of the electroweak phase transition in the early Universe. For Higgs masses in the range 46 less than or = M sub H less than or = 150 GeV and top quark masses less than 200 GeV, regions of symmetric and asymmetric vacuum coexist to below the critical temperature, with thermal equilibrium between the two phases maintained by fluctuations of both phases. We propose that the transition to the asymmetric vacuum is completed by percolation of these subcritical fluctuations. Our results are relevant to scenarios of baryogenesis that invoke a weakly first-order phase transition at the electroweak scale.

Assessment of early post-operative pain following septorhinoplasty.

PubMed

Szychta, P; Antoszewski, B

2010-11-01

To evaluate pain incidence and intensity in patients undergoing septorhinoplasty, and to assess analgesic treatment effectiveness, in the first 7 days after surgery. Prospective outcomes analysis using visual analogue scale assessment of pain intensity in the first 7 post-operative days. Fifty-seven patients were enrolled in the study, 29 women and 28 men, aged 18 to 51 years. All were treated for post-traumatic deformity of the external nose and/or nasal septum, with either septorhinoplasty or septoplasty. In the first 3 days after septorhinoplasty, patients' mean visual analogue scale pain score exceeded the range denoting 'analgesic success', and showed considerable exacerbation in the evening. Patients' pain decreased to a mean score of 15.4 one hour after administration of a nonsteroidal anti-inflammatory drug (metamizole). Analgesia is recommended for all patients in the first 3 days after septorhinoplasty, especially in the early evening.

Post-Starburst Galaxies At The End of The E+A Phase

NASA Astrophysics Data System (ADS)

Liu, Charles; Marinelli, Mariarosa; Chang, Madeleine; Lyczko, Camilla; Vega Orozco, Cecilia; SDSS-IV Collaboration

2018-06-01

Post-starburst galaxies, once thought to be rare curiosities, are now recognized to represent a key phase in the galaxy evolution. The post-starburst, or E+A phase, should however not be considered as a single, short-lived phenomenon; rather, it is an extended evolutionary process that occurs a galaxy transitions from an actively star-forming system into a quiescent one. We present a study of nearby galaxies at or near the end of the E+A phase, wherein all star formation has been quenched, the fossilized stellar population of the most recent starburst is highly localized, and the remainder of the galaxy's stellar population is old and quiescent. The luminosity and stellar age distribution of these "end-phase E+As" can provide insights into the evolution of galaxies onto and within the red sequence, from active to passive systems. This work is supported by National Science Foundation grants to CUNY College of Staten Island and the American Museum of Natural History; the College of Staten Island Office of Academic Affairs; the Sherman Fairchild Science Pathways Scholars Program (SP^2) at Barnard College; and the Alfred P. Sloan Foundation.

Examination of a modified cell cycle synchronization method and bovine nuclear transfer using synchronized early G1 phase fibroblast cells.

PubMed

Urakawa, Manami; Ideta, Atsushi; Sawada, Tokihiko; Aoyagi, Yoshito

2004-08-01

Somatic cell nuclear transfer has a low success rate, due to a high incidence of fetal loss and increased perinatal morbidity/mortality. One factor that may affect the successful development of nuclear transfer embryos is the cell cycle stage of the donor cell. In order to establish a cell cycle synchronization method that can consistently produce cloned embryos and offspring, we examined the effects of different combinations of three cell treatments on the recovery rate of mitotic phase cells using bovine fetal fibroblasts. In the first experiment, we examined the recovery rate of mitotic phase cells by a combination of treatment with a metaphase arrestant (1 microM 2-methoxyestradiol), shaking the plate and selecting cells with a diameter of 20 microns. As a result, 99% of mitotic phase cells were recovered by repeating the combined treatment of metaphase arrestant and shaking, and collection of cells with a specific diameter. In the second experiment, nuclear transfer was carried out using early G1 phase cells by choosing pairs of bridged cells derived from mitotic phase cells recovered by the combined treatment of 1 microM 2-methoxyestradiol and shaking, and collection of cells with a diameter of 20 microns. The reconstructed embryos were transferred to recipient heifers to determine post-implantation development. Development of embryos reconstructed from early G1 phase cells from the >/=6 cells stage on Day 3 to the morula-blastocyst stage on Day 6 was 100%. Ten blastocysts constructed from two cell lines were transferred into 10 recipient heifers. Nine of the 10 recipients delivered single live calves. In conclusion, mitotic phase bovine fibroblast cells were easily recovered by the combined treatments of 1 microM 2-methoxyestradiol, shaking, and selecting cells of the appropriate diameter. Furthermore, nuclear transfer using cells in the early G1 phase as donor cells gave a high rate of offspring production.

Dual phase high-temperature membranes for CO2 separation - performance assessment in post- and pre-combustion processes.

PubMed

Anantharaman, Rahul; Peters, Thijs; Xing, Wen; Fontaine, Marie-Laure; Bredesen, Rune

2016-10-20

Dual phase membranes are highly CO 2 -selective membranes with an operating temperature above 400 °C. The focus of this work is to quantify the potential of dual phase membranes in pre- and post-combustion CO 2 capture processes. The process evaluations show that the dual phase membranes integrated with an NGCC power plant for CO 2 capture are not competitive with the MEA process for post-combustion capture. However, dual phase membrane concepts outperform the reference Selexol technology for pre-combustion CO 2 capture in an IGCC process. The two processes evaluated in this work, post-combustion NGCC and pre-combustion IGCC, represent extremes in CO 2 partial pressure fed to the separation unit. Based on the evaluations it is expected that dual phase membranes could be competitive for post-combustion capture from a pulverized coal fired power plant (PCC) and pre-combustion capture from an Integrated Reforming Cycle (IRCC).

Matter bounce cosmology with a generalized single field: non-Gaussianity and an extended no-go theorem

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Yu-Bin; Cai, Yi-Fu; Quintin, Jerome

We extend the matter bounce scenario to a more general theory in which the background dynamics and cosmological perturbations are generated by a k -essence scalar field with an arbitrary sound speed. When the sound speed is small, the curvature perturbation is enhanced, and the tensor-to-scalar ratio, which is excessively large in the original model, can be sufficiently suppressed to be consistent with observational bounds. Then, we study the primordial three-point correlation function generated during the matter-dominated contraction stage and find that it only depends on the sound speed parameter. Similar to the canonical case, the shape of the bispectrummore » is mainly dominated by a local form, though for some specific sound speed values a new shape emerges and the scaling behaviour changes. Meanwhile, a small sound speed also results in a large amplitude of non-Gaussianities, which is disfavored by current observations. As a result, it does not seem possible to suppress the tensor-to-scalar ratio without amplifying the production of non-Gaussianities beyond current observational constraints (and vice versa). This suggests an extension of the previously conjectured no-go theorem in single field nonsingular matter bounce cosmologies, which rules out a large class of models. However, the non-Gaussianity results remain as a distinguishable signature of matter bounce cosmology and have the potential to be detected by observations in the near future.« less

Sampling Theory and Confidence Intervals for Effect Sizes: Using ESCI To Illustrate "Bouncing"; Confidence Intervals.

ERIC Educational Resources Information Center

Du, Yunfei

This paper discusses the impact of sampling error on the construction of confidence intervals around effect sizes. Sampling error affects the location and precision of confidence intervals. Meta-analytic resampling demonstrates that confidence intervals can haphazardly bounce around the true population parameter. Special software with graphical…

A Healthy Lifestyle Program for Latino Daughters and Mothers: The BOUNCE Overview and Process Evaluation

ERIC Educational Resources Information Center

Olvera, Norma N.; Knox, Brook; Scherer, Rhonda; Maldonado, Gabriela; Sharma, Shreela V.; Alastuey, Lisa; Bush, Jill A.

2008-01-01

Background: Few family-based healthy lifestyle programs for Latinos have been conducted, especially family programs targeting mother-daughter dyads. Purpose: To assess the acceptability and feasibility of the Behavior Opportunities Uniting Nutrition Counseling and Exercise (BOUNCE) program designed for Latino mother-daughter pairs. Methods: 92…

Rotigotine in Combination with the MAO-B Inhibitor Selegiline in Early Parkinson's Disease: A Post Hoc Analysis.

PubMed

Giladi, Nir; Asgharnejad, Mahnaz; Bauer, Lars; Grieger, Frank; Boroojerdi, Babak

2016-04-02

Monoamine oxidase B (MAO-B) inhibitors and dopamine receptor agonists are common first-line treatment options in early Parkinson's disease (PD). To evaluate the efficacy and safety of rotigotine transdermal patch as an add-on therapy to an MAO-B inhibitor in patients with early-PD. In two Phase III, randomized, double-blind, placebo-controlled studies in early-PD (SP512, SP513), patients were randomized to rotigotine (titrated to optimal dose ≤8 mg/24 h) or placebo, and maintained for 24 (SP512) or 33 (SP513) weeks. Post hoc analyses were performed on pooled data for patients receiving an MAO-B inhibitor (selegiline) at a stable dose at randomization and throughout the studies, with groups defined as "Selegiline+Rotigotine" and "Selegiline+Placebo". Outcome measures included change from baseline in Unified Parkinson's Disease Rating Scale (UPDRS) II (activities of daily living), III (motor), UPDRS II+III and responders (patients achieving ≥20%, ≥25% or ≥30% decrease in UPDRS II+III). As post hoc analyses, p-values are exploratory. 130 patients were evaluable for efficacy analyses ("Selegiline+Rotigotine": 84, "Selegiline+Placebo": 46). Combined treatment with rotigotine and selegiline improved UPDRS III and UPDRS II+III scores versus selegiline alone (LS-mean [95% CI] treatment difference for UPDRS III: -4.89 [-7.87 to -1.91], p = 0.0015; for UPDRS II+III: -5.76 [-9.71 to -1.82], p = 0.0045). Higher proportion of patients in the "Selegiline+Rotigotine" group were classified as ≥20%, ≥25% or ≥30% responders (all p < 0.001). Combined treatment appeared more effective in patients aged ≤65 years versus > 65 years (although patient numbers in the subgroups were low). Adverse event profile was consistent with the known safety profile of rotigotine. In these post hoc analyses, adjunctive treatment with rotigotine in patients already receiving an MAO-B inhibitor improved UPDRS II+III score; this appeared to be largely driven by

Volunteering for early phase gene transfer research in Parkinson disease.

PubMed

Kim, S Y H; Holloway, R G; Frank, S; Beck, C A; Zimmerman, C; Wilson, R; Kieburtz, K

2006-04-11

For early phase trials of novel interventions-such as gene transfer for Parkinson disease (PD)--whose focus is primarily on safety and tolerability, it is important that participants have a realistic understanding of the goals of such research. Recently, some have expressed concern that patients with PD may have unrealistic expectations. The authors examined why patients with PD might volunteer for invasive early phase research by interviewing 92 patients with PD and comparing those who would (n = 46) and those who would not (n = 46) participate in a hypothetical phase I gene-transfer study. The two groups' demographic, clinical, functional, and quality of life measures, as well as their understanding of the research protocol, were similar. The groups did not differ on their perception of potential for personal benefit nor on the level of likelihood of benefit they saw as a precondition for volunteering. However, those willing to participate tended to perceive lower probability of risk, were tolerant of greater probability of risk, and were more optimistic about the phase I study's potential benefits to society. They also appeared more decisive and action-oriented than the unwilling group. It is likely that the decision whether to participate in early phase PD gene transfer studies will depend mostly on patients' attitudes regarding risk, optimism about science, and an action orientation, rather than on their clinical, functional, or demographic characteristics.

Implementing Effective Mission Systems Engineering Practices During Early Project Formulation Phases

NASA Technical Reports Server (NTRS)

Moton, Tryshanda

2016-01-01

Developing and implementing a plan for a NASA space mission can be a complicated process. The needs, goals, and objectives of any proposed mission or technology must be assessed early in the Project Life Cycle. The key to successful development of a space mission or flight project is the inclusion of systems engineering in early project formulation, namely during Pre-phase A, Phase A, and Phase B of the NASA Project Life Cycle. When a space mission or new technology is in pre-development, or "pre-Formulation", feasibility must be determined based on cost, schedule, and risk. Inclusion of system engineering during project formulation is key because in addition to assessing feasibility, design concepts are developed and alternatives to design concepts are evaluated. Lack of systems engineering involvement early in the project formulation can result in increased risks later in the implementation and operations phases of the project. One proven method for effective systems engineering practice during the pre-Formulation Phase is the use of a mission conceptual design or technology development laboratory, such as the Mission Design Lab (MDL) at NASA's Goddard Space Flight Center (GSFC). This paper will review the engineering process practiced routinely in the MDL for successful mission or project development during the pre-Formulation Phase.

French policy for managing the post-accident phase of a nuclear accident.

PubMed

Gallay, F; Godet, J L; Niel, J C

2015-06-01

In 2005, at the request of the French Government, the Nuclear Safety Authority (ASN) established a Steering Committee for the Management of the Post-Accident Phase of a Nuclear Accident or a Radiological Emergency, with the objective of establishing a policy framework. Under the supervision of ASN, this Committee, involving several tens of experts from different backgrounds (e.g. relevant ministerial offices, expert agencies, local information commissions around nuclear installations, non-governmental organisations, elected officials, licensees, and international experts), developed a number of recommendations over a 7-year period. First published in November 2012, these recommendations cover the immediate post-emergency situation, and the transition and longer-term periods of the post-accident phase in the case of medium-scale nuclear accidents causing short-term radioactive release (less than 24 h) that might occur at French nuclear facilities. They also apply to actions to be undertaken in the event of accidents during the transportation of radioactive materials. These recommendations are an important first step in preparation for the management of a post-accident situation in France in the case of a nuclear accident. © The Chartered Institution of Building Services Engineers 2014.

Characterisation of Early-Life Fecal Microbiota in Susceptible and Healthy Pigs to Post-Weaning Diarrhoea

PubMed Central

Dou, Samir; Gadonna-Widehem, Pascale; Rome, Véronique; Hamoudi, Dounia; Rhazi, Larbi; Lakhal, Lyes; Larcher, Thibaut; Bahi-Jaber, Narges; Pinon-Quintana, Arturo; Guyonvarch, Alain

2017-01-01

Early-life microbial exposure is of particular importance to growth, immune system development and long-lasting health. Hence, early microbiota composition is a promising predictive biomarker for health and disease but still remains poorly characterized in regards to susceptibility to diarrhoea. In the present study, we aimed to assess if gut bacterial community diversity and composition during the suckling period were associated with differences in susceptibility of pigs to post-weaning diarrhoea. Twenty piglets from 5 sows (4 piglets / litter) were weaned in poor housing conditions to challenge their susceptibility to post-weaning diarrhoea. Two weeks after weaning, 13 pigs exhibited liquid faeces during 2 or 3 days and were defined as diarrhoeic (D) pigs. The other 7 pigs did not have diarrhea during the whole post-weaning experimental periodand were defined as healthy (H) pigs. Using a molecular characterisation of fecal microbiota with CE-SSCP fingerprint, Next Generation Sequencing and qPCR, we show that D and H pigs were mainly discriminated as early as postnatal day (PND) 7, i.e. 4 weeks before post-weaning diarrhoea occurence. At PND 7 H pigs displayed a lower evenness and a higher abundance of Prevotellaceae, Lachnospiraceae, Ruminocacaceae and Lactobacillaceae compared to D pigs. The sPLS regression method indicates that these bacterial families were strongly correlated to a higher Bacteroidetes abundance observed in PND 30 H pigs one week before diarrhoea. These results emphasize the potential of early microbiota diversity and composition as being an indicator of susceptibility to post-weaning diarrhoea. Furthermore, they support the health promoting strategies of pig herds through gut microbiota engineering. PMID:28072880

Anisotropy of Earth's D'' layer and stacking faults in the MgSiO3 post-perovskite phase.

PubMed

Oganov, Artem R; Martonák, Roman; Laio, Alessandro; Raiteri, Paolo; Parrinello, Michele

2005-12-22

The post-perovskite phase of (Mg,Fe)SiO3 is believed to be the main mineral phase of the Earth's lowermost mantle (the D'' layer). Its properties explain numerous geophysical observations associated with this layer-for example, the D'' discontinuity, its topography and seismic anisotropy within the layer. Here we use a novel simulation technique, first-principles metadynamics, to identify a family of low-energy polytypic stacking-fault structures intermediate between the perovskite and post-perovskite phases. Metadynamics trajectories identify plane sliding involving the formation of stacking faults as the most favourable pathway for the phase transition, and as a likely mechanism for plastic deformation of perovskite and post-perovskite. In particular, the predicted slip planes are {010} for perovskite (consistent with experiment) and {110} for post-perovskite (in contrast to the previously expected {010} slip planes). Dominant slip planes define the lattice preferred orientation and elastic anisotropy of the texture. The {110} slip planes in post-perovskite require a much smaller degree of lattice preferred orientation to explain geophysical observations of shear-wave anisotropy in the D'' layer.

A statistical physics viewpoint on the dynamics of the bouncing ball

NASA Astrophysics Data System (ADS)

Chastaing, Jean-Yonnel; Géminard, Jean-Christophe; Bertin, Eric

2016-06-01

We compute, in a statistical physics perspective, the dynamics of a bouncing ball maintained in a chaotic regime thanks to collisions with a plate experiencing an aperiodic vibration. We analyze in details the energy exchanges between the bead and the vibrating plate, and show that the coupling between the bead and the plate can be modeled in terms of both a dissipative process and an injection mechanism by an energy reservoir. An analysis of the injection statistics in terms of fluctuation relation is also provided.

Water Bouncing Balls: how material stiffness affects water entry

NASA Astrophysics Data System (ADS)

Truscott, Tadd

2014-03-01

It is well known that one can skip a stone across the water surface, but less well known that a ball can also be skipped on water. Even though 17th century ship gunners were aware that cannonballs could be skipped on the water surface, they did not know that using elastic spheres rather than rigid ones could greatly improve skipping performance (yet would have made for more peaceful volleys). The water bouncing ball (Waboba®) is an elastic ball used in a game of aquatic keep away in which players pass the ball by skipping it along the water surface. The ball skips easily along the surface creating a sense that breaking the world record for number of skips could easily be achieved (51 rock skips Russell Byers 2007). We investigate the physics of skipping elastic balls to elucidate the mechanisms by which they bounce off of the water. High-speed video reveals that, upon impact with the water, the balls create a cavity and deform significantly due to the extreme elasticity; the flattened spheres resemble skipping stones. With an increased wetted surface area, a large hydrodynamic lift force is generated causing the ball to launch back into the air. Unlike stone skipping, the elasticity of the ball plays an important roll in determining the success of the skip. Through experimentation, we demonstrate that the deformation timescale during impact must be longer than the collision time in order to achieve a successful skip. Further, several material deformation modes can be excited upon free surface impact. The effect of impact velocity and angle on the two governing timescales and material wave modes are also experimentally investigated. Scaling for the deformation and collision times are derived and used to establish criteria for skipping in terms of relevant physical parameters.

The Root Cause of Post-traumatic and Developmental Stress Disorder, Phase 2

DTIC Science & Technology

2013-10-01

have tested and validated. Project 2 will investigate post -mortem anatomy in subjects with major depression and/or PTSD. Both molecular and...Award Number: W81XWH-11-2-0166 TITLE: The Root Cause of Post -traumatic and Developmental Stress Disorder, Phase II PRINCIPAL INVESTIGATOR: Keith...construed as an official Department of the Army position, policy or decision unless so designated by other documentation. REPORT DOCUMENTATION PAGE

In Situ Measurements of the Post-Spinel and Post-Garnet Phase Boundaries in Pyrolite at 17-32 GPa and 1500-2400 K

NASA Astrophysics Data System (ADS)

Ye, Y.; Gu, C.; Shim, S. H.; Prakapenka, V.; Meng, Y.

2014-12-01

Recent seismic studies have revealed complex structures near 660-km depth. In order to understand the effects of composition and temperature, we measured the depth and Clapeyron slope of the post-spinel and post-garnet boundaries at the pressure-temperature conditions of 600-700 km depths in pyrolitic compositions: (1) MgO-Al2O3-SiO2 (MAS) and (2) CaO-MgO-Al2O3-SiO2-FeO (CMASF). Glass starting materials were mixed with either gold or platinum powder (10 wt%) for laser coupling and internal pressure scale. Cold compressed foils of the mixtures were loaded in the diamond-anvil cell together with Ar or KCl for thermal insulation and pressure transmission. X-ray diffraction patterns were measured for the samples in the diamond-anvil cell at in situ high pressure and high temperature combined with double side laser heating at beamlines 13-IDD (GSECARS) and 16-IDB (HPCAT) in the Advanced Photon Source. Within 5 to 8 minutes of heating, stable crystalline phase assemblages were formed and persisted with further heating for 20 to 30 minutes. A total of 160 heating cycles were conducted at different pressures and temperatures, providing tight constrains on the phase boundaries. Our data show that the post-spinel transition occurs at 23.6-24.5 GPa and 1850 K with a Clapeyron slope of -2.5(4) MPa/K if the Pt pressure scales are used, consistent with the seismic observation of the 660 discontinuity. The post-garnet boundary occurs at 24.2-27.5 GPa and 1900 - 2450 K. We found that the Clapeyron slope of the post-garnet transition increases with Fe: from 2.4 MPa/K for MAS to 6.2 MPa/K for CMASF. Below 1900 K, garnet disappears near the post-spinel boundary within the resolution of our measurements. Our new data supports the notion that the 660 discontinuity is dominated by the post-spinel phase transition below 1900 K while dominated by the post-garnet phase transition above 1900 K. However, our data indicate much larger Clapeyron slope of the post-garnet transition, suggesting

40 CFR 76.8 - Early election for Group 1, Phase II boilers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.8 Early election for Group 1... plan and: (i) If a Phase I Acid Rain permit governing the source at which the unit is located has been... chapter to include the early election plan; or (ii) If a Phase I Acid Rain permit governing the source at...

40 CFR 76.8 - Early election for Group 1, Phase II boilers.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.8 Early election for Group 1... plan and: (i) If a Phase I Acid Rain permit governing the source at which the unit is located has been... chapter to include the early election plan; or (ii) If a Phase I Acid Rain permit governing the source at...

40 CFR 76.8 - Early election for Group 1, Phase II boilers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.8 Early election for Group 1... plan and: (i) If a Phase I Acid Rain permit governing the source at which the unit is located has been... chapter to include the early election plan; or (ii) If a Phase I Acid Rain permit governing the source at...

40 CFR 76.8 - Early election for Group 1, Phase II boilers.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.8 Early election for Group 1... plan and: (i) If a Phase I Acid Rain permit governing the source at which the unit is located has been... chapter to include the early election plan; or (ii) If a Phase I Acid Rain permit governing the source at...

40 CFR 76.8 - Early election for Group 1, Phase II boilers.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.8 Early election for Group 1... plan and: (i) If a Phase I Acid Rain permit governing the source at which the unit is located has been... chapter to include the early election plan; or (ii) If a Phase I Acid Rain permit governing the source at...

Phase III Early Restoration Meeting - Corpus Christi, TX | NOAA Gulf Spill

Science.gov Websites

Areas Alabama Florida Louisiana Mississippi Texas Region-wide Open Ocean Data Media & News programmatic approach to early restoration planning for Phase III and future early restoration plans. Open

Space shuttle holddown post blast shield

NASA Technical Reports Server (NTRS)

Larracas, F. B.

1991-01-01

The original and subsequent designs of the Solid Rocket Booster/Holddown Post blast shield assemblies and their associated hardware are described. It presents the major problems encountered during their early use in the Space Shuttle Program, during the Return-to-Flight Modification Phase, and during their fabrication and validation testing phases. The actions taken to correct the problems are discussed, along with the various concepts now being considered to increase the useful life of the blast shield.

Early post-partum hematological changes in Holstein dairy cows with retained placenta.

PubMed

Moretti, Pierangelo; Probo, Monica; Morandi, Nicola; Trevisi, Erminio; Ferrari, Annarita; Minuti, Andrea; Venturini, Monica; Paltrinieri, Saverio; Giordano, Alessia

2015-01-01

Retained placenta (RP) occurs frequently in dairy cattle but little is known about the pathogenic or prognostic role of the hematological changes in this disease. This retrospective study was designed to investigate the hematological changes associated with RP in the immediate post-partum period and to assess whether these changes are associated with an acute phase reaction. Data concerning hematology, acute phase proteins, markers of inflammation and serum biochemistry performed on cows at 3±1 days in milk (DIM) from two intensive farms were extracted from the database of the ProZoo project, a research project aimed to investigate the relationship between genomic traits and bovine health and production. After application of restrictive inclusion criteria, data from 45 cows, 22 with RP and 23 controls, were statistically compared. RBC count, d-ROMs concentration, and AST activity were significantly higher in the RP group than controls. Conversely, neutrophils, thiol groups, and serum zinc concentration were significantly lower in the RP group than controls. In conclusion, although retained placenta has to be considered as a syndrome with multifactorial causes, neutropenia may be a co-factor involved in its pathogenesis. Further studies are needed to clarify whether neutropenia acts as a contributor in the pathogenesis of RP or if it is a very early consequence of the syndrome, preceding any other inflammatory changes in blood. Copyright © 2014 Elsevier B.V. All rights reserved.

The progamic phase of an early-divergent angiosperm, Annona cherimola (Annonaceae)

PubMed Central

Lora, J.; Hormaza, J. I.; Herrero, M.

2010-01-01

Background and Aims Recent studies of reproductive biology in ancient angiosperm lineages are beginning to shed light on the early evolution of flowering plants, but comparative studies are restricted by fragmented and meagre species representation in these angiosperm clades. In the present study, the progamic phase, from pollination to fertilization, is characterized in Annona cherimola, which is a member of the Annonaceae, the largest extant family among early-divergent angiosperms. Beside interest due to its phylogenetic position, this species is also an ancient crop with a clear niche for expansion in subtropical climates. Methods The kinetics of the reproductive process was established following controlled pollinations and sequential fixation. Gynoecium anatomy, pollen tube pathway, embryo sac and early post-fertilization events were characterized histochemically. Key Results A plesiomorphic gynoecium with a semi-open carpel shows a continuous secretory papillar surface along the carpel margins, which run from the stigma down to the obturator in the ovary. The pollen grains germinate in the stigma and compete in the stigma-style interface to reach the narrow secretory area that lines the margins of the semi-open stylar canal and is able to host just one to three pollen tubes. The embryo sac has eight nuclei and is well provisioned with large starch grains that are used during early cellular endosperm development. Conclusions A plesiomorphic simple gynoecium hosts a simple pollen–pistil interaction, based on a support–control system of pollen tube growth. Support is provided through basipetal secretory activity in the cells that line the pollen tube pathway. Spatial constraints, favouring pollen tube competition, are mediated by a dramatic reduction in the secretory surface available for pollen tube growth at the stigma–style interface. This extramural pollen tube competition contrasts with the intrastylar competition predominant in more recently derived

Early seizures and temporal lobe trauma predict post-traumatic epilepsy: A longitudinal study.

PubMed

Tubi, Meral A; Lutkenhoff, Evan; Blanco, Manuel Buitrago; McArthur, David; Villablanca, Pablo; Ellingson, Benjamin; Diaz-Arrastia, Ramon; Van Ness, Paul; Real, Courtney; Shrestha, Vikesh; Engel, Jerome; Vespa, Paul M; Agoston, Denes; Au, Alicia; Bell, Michael J; Branch, Craig; Buitrago Blanco, Manuel; Bullock, Ross; Claassen, Jan; Clarke, Robert; Cloyd, James; Coles, Lisa; Crawford, Karen; Diaz-Arrastia, Ramon; Duncan, Dominique; Ellingson, Benjamin; Engel, Jerome; Foreman, Brandon; Galanopoulou, Aristea; Gilmore, Emily; Olli, Grohn; Harris, Neil; Hartings, Jed; Lawrence, Hirsch; Hunn, Martin; Jette, Nathalie; Johnston, Leigh; Jones, Nigel; Kanner, Andres; McArthur, David; Monti, Martin; Morokoff, Andrew; Moshe, Solomon; Mowrey, Wenzhu; Naughton, Tomas; O'Brien, Terence; O'Phelan, Kristine; Pitkanen, Asla; Raman, Rema; Robertson, Courtney; Rosenthal, Eric; Shultz, Sandy; Snutch, Terrance; Staba, Richard; Toga, Arthur; Van Horn, Jack; Vespa, Paul; Willyerd, Frederick; Zimmermann, Lara

2018-05-31

Injury severity after traumatic brain injury (TBI) is a well-established risk factor for the development of post-traumatic epilepsy (PTE). However, whether lesion location influences the susceptibility of seizures and development of PTE longitudinally has yet to be defined. We hypothesized that lesion location, specifically in the temporal lobe, would be associated with an increased incidence of both early seizures and PTE. As secondary analysis measures, we assessed the degree of brain atrophy and functional recovery, and performed a between-group analysis, comparing patients who developed PTE with those who did not develop PTE. We assessed early seizure incidence (n = 90) and longitudinal development of PTE (n = 46) in a prospective convenience sample of patients with moderate-severe TBI. Acutely, patients were monitored with prospective cEEG and a high-resolution Magnetic Resonance Imaging (MRI) scan for lesion location classification. Chronically, patients underwent a high-resolution MRI, clinical assessment, and were longitudinally monitored for development of epilepsy for a minimum of 2 years post-injury. Early seizures, occurring within the first week post-injury, occurred in 26.7% of the patients (n = 90). Within the cohort of subjects who had evidence of early seizures (n = 24), 75% had a hemorrhagic temporal lobe injury on admission. For longitudinal analyses (n = 46), 45.7% of patients developed PTE within a minimum of 2 years post-injury. Within the cohort of subjects who developed PTE (n = 21), 85.7% had a hemorrhagic temporal lobe injury on admission and 38.1% had early (convulsive or non-convulsive) seizures on cEEG monitoring during their acute ICU stay. In a between-group analysis, patients with PTE (n = 21) were more likely than patients who did not develop PTE (n = 25) to have a hemorrhagic temporal lobe injury (p < 0.001), worse functional recovery (p = 0.003), and greater temporal lobe atrophy (p�

Under-flap stromal bed CXL for early post-LASIK ectasia: a novel treatment technique.

PubMed

Wallerstein, Avi; Adiguzel, Eser; Gauvin, Mathieu; Mohammad-Shahi, Nima; Cohen, Mark

2017-01-01

Collagen cross-linking (CXL) for post-laser-assisted in situ keratomileusis (LASIK) ectasia (PLE) is traditionally performed either epi-on or epi-off on the corneal surface. This study describes a novel technique in treating early PLE with under-flap CXL (ufCXL) to the stromal bed and reports on 6-month outcomes. Case series of seven patients (eight eyes) with topography-diagnosed early PLE treated with ufCXL. Inclusion criteria were early, mild PLE defined as new-onset postoperative manifest refraction cylinder ≤1.50 D, with new topographic inferior steepening consistent with ectasia, uncorrected distance visual acuity (UDVA) of 20/40 or better, and corrected distance visual acuity (CDVA) of 20/25 or better. Existing LASIK flap was lifted, riboflavin was applied directly to the stromal bed, flap was repositioned, and 18 mW/cm 2 ultraviolet light was applied for 3 minutes to the corneal surface. Post-ufCXL manifest refraction, UDVA and CDVA, corneal cylinder, K max , and corneal irregularity index were compared with pre-ufCXL measurements. Patients had a pre-ufCXL sphere of 0.09±0.48 D and cylinder of -0.78±0.49 D. At 6 months, post-ufCXL sphere (0.06±0.8 D; P =0.89) and cylinder (-1.09±0.76 D, P =0.26) were unchanged. Cumulative post-ufCXL UDVA was unchanged, achieving 20/20, 20/30, and 20/40 in 25%, 88%, and 88%, respectively, compared with 13%, 63%, and 88% pre-ufCXL ( P =0.68). Post-ufCXL CDVA was unchanged ( P =0.93) with a gain of one line in two eyes, a loss of one line in one eye, and five eyes unchanged. The efficacy index ( P =0.76), safety index ( P =0.89), K max ( P =0.94), and corneal irregularity index ( P =0.73) were also unchanged. Preliminary results with ufCXL for early PLE are promising, demonstrating maintenance of visual accuracy, efficacy, safety, K max , and cylinder, with much quicker recovery times than surface CXL.

Architecture Study on Telemetry Coverage for Immediate Post-Separation Phase

NASA Technical Reports Server (NTRS)

Cheung, Kar-Ming; Lee, Charles; Kellogg, Kent; Stocklin, Frank; Zillig, David; Fielhauer, Karl

2008-01-01

This document is the viewgraphs that accompanies a paper that presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed. The main results of this study are as follows: 1) At low altitude (< 10000 km) when most post-separation critical operations are executed, Earth-based network (e.g. Deep Space Network (DSN)) can only provide limited coverage, whereas space-based network (e.g. Space Network (SN)) can provide continuous coverage. 2) Commercial-off-the-shelf SN compatible transmitters are available for small satellite applications. In this paper we present the detailed coverage analysis of Earth-based and Space-based networks. We identify the key functional and performance requirements of the architecture, and describe the proposed selection criteria of the spacecraft transmitter. We conclude the paper with a proposed forward plan.

Phase III Early Restoration Meeting - Lake Charles, LA | NOAA Gulf Spill

Science.gov Websites

Areas Alabama Florida Louisiana Mississippi Texas Region-wide Open Ocean Data Media & News early restoration planning for Phase III and future early restoration plans. Open House: 5:30pm Public

Coexistence of bounded and unbounded motions in a bouncing ball model

NASA Astrophysics Data System (ADS)

Marò, Stefano

2013-05-01

We consider the model describing the vertical motion of a ball falling with constant acceleration on a wall and elastically reflected. The wall is supposed to move in the vertical direction according to a given periodic function f. We apply the Aubry-Mather theory to the generating function in order to prove the existence of bounded motions with prescribed mean time between the bounces. As the existence of unbounded motions is known, it is possible to find a class of functions f that allow both bounded and unbounded motions.

AI canis minoris, a pulsating low-mass supergiant at an early transition phase from the AGB to the post-AGB stage of evolution

NASA Astrophysics Data System (ADS)

Arkhipova, V. P.; Ikonnikova, N. P.; Esipov, V. F.; Komissarova, G. V.

2017-06-01

The U BV photometry and low-resolution spectroscopy for the semiregular variable AI CMi, a candidate for post-AGB objects, performed in 1996-2016 and 2000-2013, respectively, are presented. The star showed multiperiodic brightness variations with an amplitude up to 1\\underset{\\cdot}{m} 5 in the V band, a significant (up to 0\\underset{\\cdot}{m} 4) bluing of the B - V and U - B colors as the star faded, and a change of its spectrum from G5 I to K3-5 I, depending on its brightness. A possible long-term fading of AI CMi below 8\\underset{\\cdot}{m} 5 in the period from May 2013 to early 2015 is observed in the light curve. The colors in this episode did not change the pattern of their unusual behavior with brightness. The main feature of the spectrum for AI CMi is the appearance and strengthening of TiO absorption bands as its brightness declines, which are atypical in the spectra of ordinary G5-K3 supergiants. The bluing of the B - V and U - B colors is interpreted as the blanketing of stellar radiation predominantly in V (and to a lesser extent in B) by the TiO absorption bands whose intensity increases dramatically with decreasing brightness. Another cause of the bluing can be the scattering of stellar radiation by small dust particles in the gas-dust shell of AI CMi. The star's continuum-normalized spectra over the period from 2000 to 2013 in the wavelength range 4200 to 7700 or 9200 Å are presented. These were taken at different phases of the pulsation cycle and clearly demonstrate the behavior of the TiO absorption bands depending on the V magnitude and B - V color. The equivalent widths of individual TiO bands weremeasured, and their correlation with the photometric parameters of the star is shown. AI CMi belongs to the O-rich branch of AGB/post-AGB supergiants and has a luminosity of 4000 L ⊙ at a distance of 1500 ± 700 pc. The mass of AI CMi is most likely small and close to the lower mass limit for post-AGB stars. The connection of the star

Evidence that Clouds of keV Hydrogen Ion Clusters Bounce Elastically from a Solid Surface

NASA Technical Reports Server (NTRS)

Lewis, R. A.; Martin, James J.; Chakrabarti, Suman; Rodgers, Stephen L. (Technical Monitor)

2002-01-01

The behavior of hydrogen ion clusters is tested by an inject/hold/extract technique in a Penning-Malmberg trap. The timing pattern of the extraction signals is consistent with the clusters bouncing elastically from a detector several times. The ion clusters behave more like an elastic fluid than a beam of ions.

Electrostatic drift instability in a magnetotail configuration: The role of bouncing electrons

NASA Astrophysics Data System (ADS)

Fruit, G.; Louarn, P.; Tur, A.

2017-03-01

To understand the possible destabilization of two-dimensional current sheets, a kinetic model is proposed to describe the resonant interaction between electrostatic modes and trapped electrons that bounce within the sheet. This work follows the initial investigation by Tur, Louarn, and Yanovsky [Phys. Plasmas 17, 102905 (2010)] and Fruit, Louarn, and Tur [Phys. Plasmas 20, 022113 (2013)] that is revised and extended. Using a quasi-dipolar equilibrium state, the linearized gyro-kinetic Vlasov equation is solved for electrostatic fluctuations with a period of the order of the electron bounce period. Using an appropriated Fourier expansion of the particle motion along the magnetic field, the complete time integration of the non-local perturbed distribution functions is performed. The dispersion relation for electrostatic modes is then obtained through the quasineutrality condition. It is found that for a mildly stretched configuration ( L ˜8 ), strongly unstable electrostatic modes may develop in the current sheet with the growth rate of the order of a few seconds provided that the background density gradient responsible for the diamagnetic drift effects is sharp enough: typical length scale over one Earth radius or less. However, when this condition in the density gradient is not met, these electrostatic modes grow too slowly to be accountable for a rapid destabilization of the magnetic structure. This strong but finely tuned instability may offer opportunities to explain features in magnetospheric substorms.

A new post-phase rotation based dynamic receive beamforming architecture for smartphone-based wireless ultrasound imaging

NASA Astrophysics Data System (ADS)

Park, Minsuk; Kang, Jeeun; Lee, Gunho; Kim, Min; Song, Tai-Kyong

2016-04-01

Recently, a portable US imaging system using smart devices is highlighted for enhancing the portability of diagnosis. Especially, the system combination can enhance the user experience during whole US diagnostic procedures by employing the advanced wireless communication technology integrated in a smart device, e.g., WiFi, Bluetooth, etc. In this paper, an effective post-phase rotation-based dynamic receive beamforming (PRBF-POST) method is presented for wireless US imaging device integrating US probe system and commercial smart device. In conventional, the frame rate of conventional PRBF (PRBF-CON) method suffers from the large amount of calculations for the bifurcated processing paths of in-phase and quadrature signal components as the number of channel increase. Otherwise, the proposed PRBF-POST method can preserve the frame rate regardless of the number of channels by firstly aggregating the baseband IQ data along the channels whose phase quantization levels are identical ahead of phase rotation and summation procedures on a smart device. To evaluate the performance of the proposed PRBF-POST method, the pointspread functions of PRBF-CON and PRBF-POST methods were compared each other. Also, the frame rate of each PRBF method was measured 20-times to calculate the average frame rate and its standard deviation. As a result, the PRBFCON and PRBF-POST methods indicates identical beamforming performance in the Field-II simulation (correlation coefficient = 1). Also, the proposed PRBF-POST method indicates the consistent frame rate for varying number of channels (i.e., 44.25, 44.32, and 44.35 fps for 16, 64, and 128 channels, respectively), while the PRBF-CON method shows the decrease of frame rate as the number of channel increase (39.73, 13.19, and 3.8 fps). These results indicate that the proposed PRBF-POST method can be more advantageous for implementing the wireless US imaging system than the PRBF-CON method.

Early visual processing is enhanced in the midluteal phase of the menstrual cycle.

PubMed

Lusk, Bethany R; Carr, Andrea R; Ranson, Valerie A; Bryant, Richard A; Felmingham, Kim L

2015-12-01

Event-related potential (ERP) studies have revealed an early attentional bias in processing unpleasant emotional images in women. Recent neuroimaging data suggests there are significant differences in cortical emotional processing according to menstrual phase. This study examined the impact of menstrual phase on visual emotional processing in women compared to men. ERPs were recorded from 28 early follicular women, 29 midluteal women, and 27 men while they completed a passive viewing task of neutral and low- and high- arousing pleasant and unpleasant images. There was a significant effect of menstrual phase in early visual processing, as midluteal women displayed significantly greater P1 amplitude at occipital regions to all visual images compared to men. Both midluteal and early follicular women displayed larger N1 amplitudes than men (although this only reached significance for the midluteal group) to the visual images. No sex or menstrual phase differences were apparent in later N2, P3, or LPP. A condition effect demonstrated greater P3 and LPP amplitude to highly-arousing unpleasant images relative to all other stimuli conditions. These results indicate that women have greater early automatic visual processing compared to men, and suggests that this effect is particularly strong in women in the midluteal phase at the earliest stage of visual attention processing. Our findings highlight the importance of considering menstrual phase when examining sex differences in the cortical processing of visual stimuli. Copyright © 2015 Elsevier Ltd. All rights reserved.

Statistical controversies in clinical research: early-phase adaptive design for combination immunotherapies.

PubMed

Wages, N A; Slingluff, C L; Petroni, G R

2017-04-01

In recent years, investigators have asserted that the 3 + 3 design lacks flexibility, making its use in modern early-phase trial settings, such as combinations and/or biological agents, inefficient. More innovative approaches are required to address contemporary research questions, such as those posed in trials involving immunotherapies. We describe the implementation of an adaptive design for identifying an optimal treatment regimen, defined by low toxicity and high immune response, in an early-phase trial of a melanoma helper peptide vaccine plus novel adjuvant combinations. Operating characteristics demonstrate the ability of the method to effectively recommend optimal regimens in a high percentage of trials with reasonable sample sizes. The proposed design is a practical, early-phase, adaptive method for use with combined immunotherapy regimens. This design can be applied more broadly to early-phase combination studies, as it was used in an ongoing study of two small molecule inhibitors in relapsed/refractory mantle cell lymphoma. © The Author 2016. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

The early use of botulinum toxin in post-stroke spasticity: study protocol for a randomised controlled trial.

PubMed

Lindsay, Cameron; Simpson, Julie; Ispoglou, Sissi; Sturman, Steve G; Pandyan, Anand D

2014-01-08

Patients surviving stroke but who have significant impairment of function in the affected arm are at more risk of developing pain, stiffness and contractures. The abnormal muscle activity, associated with post-stroke spasticity, is thought to be causally associated with the development of these complications. Treatment of spasticity is currently delayed until a patient develops signs of these complications. This protocol is for a phase II study that aims to identify whether using OnabotulinumtoxinA (BoNT-A) in combination with physiotherapy early post stroke when initial abnormal muscle activity is neurophysiologically identified can prevent loss of range at joints and improve functional outcomes.The trial uses a screening phase to identify which people are appropriate to be included in a double blind randomised placebo-controlled trial. All patients admitted to Sandwell and West Birmingham NHS Trust Hospitals with a diagnosis of stroke will be screened to identify functional activity in the arm. Those who have no function will be appropriate for further screening. Patients who are screened and have abnormal muscle activity identified on EMG will be given electrical stimulation to forearm extensors for 3 months and randomised to have either injections of BoNT-A or normal saline. The primary outcome measure is the action research arm test - a measure of arm function. Further measures include spasticity, stiffness, muscle strength and fatigue as well as measures of quality of life, participation and caregiver strain. ISRCTN57435427, EudraCT2010-021257-39, NCT01882556.

Prostate-specific antigen bounce after high-dose-rate prostate brachytherapy and hypofractionated external beam radiotherapy.

PubMed

Patel, Nita; Souhami, Luis; Mansure, Jose João; Duclos, Marie; Aprikian, Armen; Faria, Sergio; David, Marc; Cury, Fabio L

2014-01-01

To report the frequency, timing, and magnitude of prostate-specific antigen (PSA) bounce (PB) in patients who received high-dose-rate (HDR) brachytherapy (HDRB) plus hypofractionated external beam radiation therapy (HypoRT) and to assess a possible correlation between PB and biochemical failure (BF). Patients with intermediate-risk prostate cancer received 10Gy single-fraction (192)Ir HDRB followed by 50Gy in 20 daily fractions of HypoRT without androgen deprivation therapy. All patients had a minimum 2-year followup. The PB was defined as PSA elevation higher than 0.2ng/mL from previous measurement with subsequent drop to pre-bounce level. The BF was defined as PSA nadir+2ng/mL. A total of 114 patients treated between 2001 and 2009 were eligible for analysis. At a median followup of 66 months, the PB was found in 45 (39%) patients with a median time to bounce of 16 months (range, 3-76 months). The median time to PSA normalization after a PB was 9 months (range, 2-40 months). The median magnitude of PB was 0.45ng/mL (range, 0.2-6.62). The BF occurred in 12 (10.5%) patients of whom three had a PB. Median time to BF was 52.5 months. Four patients (3.5%) in the PB group fit the criteria for BF. The PB is common after HDRB and HypoRT and can occur up to 76 months after treatment. It can rarely fit the criteria for BF. The time to PB is shorter than the time to BF. There is a lower incidence of BF in patients with a PB. An acknowledgment of this phenomenon should be made when interpreting PSA results during followup to prevent unnecessary interventions. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

Platelet aggregation but not activation and degranulation during the acute post-ischemic reperfusion phase in livers with no underlying disease

PubMed Central

van Golen, Rowan F.; Stevens, Katarzyna M.; Colarusso, Pina; Jaeschke, Hartmut; Heger, Michal

2016-01-01

Background Platelets and P-selectin (CD62P) play an unequivocal role in the pathology of hepatic ischemia/reperfusion (I/R) injury. Inhibition or knock-out of P-selectin or immunodepletion of platelets results in amelioration of post-ischemic inflammation, reduced hepatocellular damage, and improved survival. However, P-selectin expression on platelets and endothelial cells, which concurs with platelet activation, has never been clearly demonstrated in I/R-subjected livers. Aims To determine whether platelets become activated and degranulate in the acute phase of liver I/R and whether the platelets interact with neutrophils. Methods Hepatic I/R was induced in male C57BL/6J mice (N = 12) using 37.5-min ischemia time. Platelets, endothelial cells, and neutrophils were fluorescently labeled by systemic administration of non-blocking antibodies. Cell kinetics were monitored by intravital spinning disk confocal microscopy during 90 min of reperfusion. Image analysis and quantification was performed with dedicated software. Results Platelets adhered to sinusoids more extensively in post-ischemic livers compared to livers not subjected to I/R and formed aggregates, which occurred directly after ischemia. Platelets and endothelial cells did not express P-selectin in post-ischemic livers. There was no interaction between platelets and neutrophils. Conclusions Platelets aggregate but do not become activated and do not degranulate in post-ischemic livers. There is no platelet-neutrophil interplay during the early reperfusion phase in a moderate model of hepatic I/R injury. The mechanisms underlying the biological effects of platelets and P-selectin in this setting warrant further investigation. Relevance for patients I/R in surgical liver patients may compromise outcome due to post-ischemic oxidative stress and sterile inflammation. Both processes are mediated in part by platelets. Understanding platelet function during I/R is key to developing effective interventions for I

Big-bounce cosmology from quantum gravity: The case of a cyclical Bianchi I universe

NASA Astrophysics Data System (ADS)

Moriconi, Riccardo; Montani, Giovanni; Capozziello, Salvatore

2016-07-01

We analyze the classical and quantum dynamics of a Bianchi I model in the presence of a small negative cosmological constant characterizing its evolution in term of the dust-time dualism. We demonstrate that in a canonical metric approach, the cosmological singularity is removed in correspondence to a positive defined value of the dust energy density. Furthermore, the quantum big bounce is connected to the Universe's turning point via a well-defined semiclassical limit. Then we can reliably infer that the proposed scenario is compatible with a cyclical universe picture. We also show how, when the contribution of the dust energy density is sufficiently high, the proposed scenario can be extended to the Bianchi IX cosmology and therefore how it can be regarded as a paradigm for the generic cosmological model. Finally, we investigate the origin of the observed cutoff on the cosmological dynamics, demonstrating how the big-bounce evolution can be mimicked by the same semiclassical scenario, where the negative cosmological constant is replaced via a polymer discretization of the Universe's volume. A direct proportionality law between these two parameters is then established.

Modeling of breakdown during the post-arc phase of a vacuum circuit breaker

NASA Astrophysics Data System (ADS)

Sarrailh, P.; Garrigues, L.; Boeuf, J. P.; Hagelaar, G. J. M.

2010-12-01

After a high-current interruption in a vacuum circuit breaker (VCB), the electrode gap is filled with a high density copper vapor plasma in a large copper vapor density (~1022 m-3). The copper vapor density is sustained by electrode evaporation. During the post-arc phase, a rapidly increasing voltage is applied to the gap, and a sheath forms and expands, expelling the plasma from the gap when circuit breaking is successful. There is, however, a risk of breakdown during that phase, leading to the failure of the VCB. Preventing breakdown during the post-arc phase is an important issue for the improvement of VCB reliability. In this paper, we analyze the risk of Townsend breakdown in the high copper vapor density during the post-arc phase using a numerical model that takes into account secondary electron emission, volume ionization, and plasma and neutral transport, for given electrode temperatures. The simulations show that fast neutrals created in the cathode sheath by charge exchange collisions with ions generate a very large secondary electron emission current that can lead to Townsend breakdown. The results also show that the risk of failure of the VCB due to Townsend breakdown strongly depends on the electrode temperatures (which govern the copper vapor density) and becomes important for temperatures greater than 2100 K, which can be reached in vacuum arcs. The simulations also predict that a hotter anode tends to increase the risk of Townsend breakdown.

Implementing the Bounce Back Trauma Intervention in Urban Elementary Schools: A Real-World Replication Trial

ERIC Educational Resources Information Center

Santiago, Catherine DeCarlo; Raviv, Tali; Ros, Anna Maria; Brewer, Stephanie K.; Distel, Laura M. L.; Torres, Stephanie A.; Fuller, Anne K.; Lewis, Krystal M.; Coyne, Claire A.; Cicchetti, Colleen; Langley, Audra K.

2018-01-01

The current study provides the first replication trial of Bounce Back, a school-based intervention for elementary students exposed to trauma, in a different school district and geographical area. Participants in this study were 52 1st through 4th graders (M[subscript age] = 7.76 years; 65% male) who were predominately Latino (82%). Schools were…

Under-flap stromal bed CXL for early post-LASIK ectasia: a novel treatment technique

PubMed Central

Wallerstein, Avi; Adiguzel, Eser; Gauvin, Mathieu; Mohammad-Shahi, Nima; Cohen, Mark

2017-01-01

Purpose Collagen cross-linking (CXL) for post-laser-assisted in situ keratomileusis (LASIK) ectasia (PLE) is traditionally performed either epi-on or epi-off on the corneal surface. This study describes a novel technique in treating early PLE with under-flap CXL (ufCXL) to the stromal bed and reports on 6-month outcomes. Patients and methods Case series of seven patients (eight eyes) with topography-diagnosed early PLE treated with ufCXL. Inclusion criteria were early, mild PLE defined as new-onset postoperative manifest refraction cylinder ≤1.50 D, with new topographic inferior steepening consistent with ectasia, uncorrected distance visual acuity (UDVA) of 20/40 or better, and corrected distance visual acuity (CDVA) of 20/25 or better. Existing LASIK flap was lifted, riboflavin was applied directly to the stromal bed, flap was repositioned, and 18 mW/cm2 ultraviolet light was applied for 3 minutes to the corneal surface. Post-ufCXL manifest refraction, UDVA and CDVA, corneal cylinder, Kmax, and corneal irregularity index were compared with pre-ufCXL measurements. Results Patients had a pre-ufCXL sphere of 0.09±0.48 D and cylinder of −0.78±0.49 D. At 6 months, post-ufCXL sphere (0.06±0.8 D; P=0.89) and cylinder (−1.09±0.76 D, P=0.26) were unchanged. Cumulative post-ufCXL UDVA was unchanged, achieving 20/20, 20/30, and 20/40 in 25%, 88%, and 88%, respectively, compared with 13%, 63%, and 88% pre-ufCXL (P=0.68). Post-ufCXL CDVA was unchanged (P=0.93) with a gain of one line in two eyes, a loss of one line in one eye, and five eyes unchanged. The efficacy index (P=0.76), safety index (P=0.89), Kmax (P=0.94), and corneal irregularity index (P=0.73) were also unchanged. Conclusion Preliminary results with ufCXL for early PLE are promising, demonstrating maintenance of visual accuracy, efficacy, safety, Kmax, and cylinder, with much quicker recovery times than surface CXL. PMID:28031696

Early Diagnosis and Intervention Strategies for Post-Traumatic Heterotopic Ossification in Severely Injured Extremities

DTIC Science & Technology

2016-12-01

the study for the presence or absence of ectopic bone formation at the indicated time points post injury (Table 1.). 8 Table 1. Incidence of HO...1 Award Number: W81XWH-12-2-0119 TITLE: Early Diagnosis and Intervention Strategies for Post -Traumatic Heterotopic Ossification in Severely...2016 TYPE OF REPORT: Final PREPARED FOR: U.S. Army Medical Research and Materiel Command Fort Detrick, Maryland 21702-5012 DISTRIBUTION STATEMENT

Phase space holes and synchronized BGK modes in autoresonantly driven, Penning-trapped electron clouds

NASA Astrophysics Data System (ADS)

Friedland, Lazar; Fajans, Joel; Bertsche, Will; Wurtele, Jonathan

2003-10-01

We study excitation and control of BGK modes in pure electron plasmas in a Penning trap. We apply an oscillating external potential with a negatively chirped frequency. This drive resonates with, and phase-locks to, a group of axially bouncing electrons in the trap. All initially phase-locked electrons remain phase-locked during the chirp (the autoresonance phenomenon), while some new particles are added to the resonant group, as the bucket moves through the phase space. This creates an oscillating in space and slowly evolving in energy hole in the phase space distribution of the electrons. The electron density perturbation associated with this evolving hole yields a BGK mode synchronized with the drive. The local depth of the hole in phase space, and, thus, the amplitude of the mode are controlled by the external parameter (the driving frequency). The process is reversible, so that the BGK mode can be returned to its nearly initial state, by reversing the direction of variation of the driving frequency. A kinetic theory of this excitation process is developed. The theory uses results on passage through, and capture into, bounce resonance in the system from Monte Carlo simulations of resonant bucket dynamics. We discuss the dependence of the excited BGK mode on the drive frequency chirp rate and other plasma parameters and compare these predictions with experiments.

Disaster: would your community bounce back?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sims, Benjamin H

What makes some communities or organizations able to quickly bounce back from a disaster, while others take a long time to recover? This question has become very important for emergency planners in federal, state, and local government - particularly since the 9/11 attacks and Hurricane Katrina, which nearly destroyed New Orleans five years ago. These events have made people aware that we can't always prevent disasters, but might be able to improve the ability of communities and regions to respond to and bounce back from major disruptions. Social scientists have found that most communities are, in fact, quite resilient tomore » most disasters. People tend to work together, overcome divisions, identify problems, and develop improvised solutions. This often leads to a greater sense of community and a sense of personal accomplishment. Long-term recovery can be harder, but rebuilding can create jobs and stimulate economies. Communities may even end up better than they were before. But there are some disturbing exceptions to this trend, including Hurricane Katrina. The hurricane killed many people, the federal and local emergency response was not effective, people who could not evacuate were housed in the Superdome and Convention Center in terrible conditions, crime was prevalent, and local government did not appear to have control over the situation. A significant portion of the population was eventually evacuated to other cities. Even five years later, many people have not returned, and large parts of the city have not been rebuilt. Clearly, New Orleans lacked sufficient resilience to overcome a disaster of the magnitude of Katrina. There are four factors that social scientists are beginning to agree are important for community resilience: (1) A strong, diverse economy - Stable jobs, good incomes, diversity of industries, personal savings; (2) Robust social networks - Community members know each other, help each other, and have connections outside the community; (3

Proteomic analysis of early phase of conidia germination in Aspergillus nidulans.

PubMed

Oh, Young Taek; Ahn, Chun-Seob; Kim, Jeong Geun; Ro, Hyeon-Su; Lee, Chang-Won; Kim, Jae Won

2010-03-01

In order to investigate proteins involved in early phase of conidia germination, proteomic analysis was performed using two-dimensional gel electrophoresis (2D-GE) in conjunction with MALDI-TOF mass spectrometry (MS). The expression levels of 241 proteins varied quantitatively with statistical significance (P<0.05) at the early phase of the germination stage. Out of these 57 were identified by MALDI-TOF MS. Through classification of physiological functions from Conserved Domain Database analysis, among the identified proteins, 21, 13, and 6 proteins were associated with energy metabolism, protein synthesis, and protein folding process, respectively. Interestingly, eight proteins, which are involved in detoxification of reactive oxygen species (ROS) including catalase A, thioredoxin reductase, and mitochondrial peroxiredoxin, were also identified. The expression levels of the genes were further confirmed using Northern blot and reverse transcriptase (RT)-PCR analyses. This study represents the first proteomic analysis of early phase of conidia germination and will contribute to a better understanding of the molecular events involved in conidia germination process. Copyright (c) 2009 Elsevier Inc. All rights reserved.

[Basic requirements on post-marketing clinical re-evaluation of chinese medicine and phase IV clinical trials].

PubMed

Xie, Yanming; Wang, Yanping; Tian, Feng; Wang, Yongyan

2011-10-01

As information on safety and effectiveness is not comprehensive, gained from the researches for listing approval of Chinese medicine, it is very necessary to conduct post-marketing clinical re-evaluation of Chinese medicine. Effectiveness, safety and economic evaluation are three main aspects of post-marketing clinical re-evaluation. In this paper, the difference and relations between the post-marketing clinical re-evaluation and the phase IV clinical trials were discussed, and the basic requests and suggestions were proposed, according to the domestic and foreign relevant regulations and experts' suggestions, and discussed the requirements of the phase IV clinical trials on indications, design methods, inclusion and exclusion criteria, sample size, etc.

Stress exposure in early post-natal life reduces telomere length: an experimental demonstration in a long-lived seabird

PubMed Central

Herborn, Katherine A.; Heidinger, Britt J.; Boner, Winnie; Noguera, Jose C.; Adam, Aileen; Daunt, Francis; Monaghan, Pat

2014-01-01

Exposure to stressors early in life is associated with faster ageing and reduced longevity. One important mechanism that could underlie these late life effects is increased telomere loss. Telomere length in early post-natal life is an important predictor of subsequent lifespan, but the factors underpinning its variability are poorly understood. Recent human studies have linked stress exposure to increased telomere loss. These studies have of necessity been non-experimental and are consequently subjected to several confounding factors; also, being based on leucocyte populations, where cell composition is variable and some telomere restoration can occur, the extent to which these effects extend beyond the immune system has been questioned. In this study, we experimentally manipulated stress exposure early in post-natal life in nestling European shags (Phalacrocorax aristotelis) in the wild and examined the effect on telomere length in erythrocytes. Our results show that greater stress exposure during early post-natal life increases telomere loss at this life-history stage, and that such an effect is not confined to immune cells. The delayed effects of increased telomere attrition in early life could therefore give rise to a ‘time bomb’ that reduces longevity in the absence of any obvious phenotypic consequences early in life. PMID:24648221

Early Diagnosis and Intervention Strategies for Post-Traumatic Heterotopic Ossification in Severely Injured Extremities

DTIC Science & Technology

2016-12-01

the study for the presence or absence of ectopic bone formation at the indicated time points post injury (Table 1.). 8 Table 1. Incidence of HO at...7, 10, 14, and 21 days post injury 42 Palovarotene Suppresses Early Chondrogenic and Osteogenic Differentiation In this set of studies we...using MicroCT imaging to quantitate total new bone and ectopic bone (non-associated with cortical margins) volume. In a second study arm, serum was

The Bounce of SL-9 Impact Ejecta Plumes on Re-Entry

NASA Astrophysics Data System (ADS)

Deming, L. D.; Harrington, J.

1996-09-01

We have generated synthetic light curves of the re-entry of SL-9 ejecta plumes into Jupiter's atmosphere and have modeled the periodic oscillation of the observed R plume light curves (P. D. Nicholson et al. 1995, Geophys. Res. Lett. 22, 1613--1616) as a hydrodynamic bounce. Our model is separated into plume and atmospheric components. The plume portion of the model is a ballistic Monte Carlo calculation (Harrington and Deming, this meeting). In this paper we describe the atmospheric portion of the model. The infalling plume is divided over a spatial grid (in latitude/longitude). The plume is layered, and joined to a 1-D Lagrangian radiative-hydrodynamic model of the atmosphere, at each grid point. The radiative-hydrodynamic code solves the momentum, energy, and radiative transfer equations for both the infalling plume layers and the underlying atmosphere using an explicit finite difference scheme. It currently uses gray opacities for both the plume and the atmosphere, and the calculations indicate that a much greater opacity is needed for the plume than for the atmosphere. We compute the emergent infrared intensity at each grid point, and integrate spatially to yield a synthetic light curve. These curves exhibit many features in common with observed light curves, including a rapid rise to maximum light followed by a gradual decline due to radiative damping. Oscillatory behavior (the ``bounce'') is a persistent feature of the light curves, and is caused by the elastic nature of the plume impact. In addition to synthetic light curves, the model also calculates temperature profiles for the jovian atmosphere as heated by the plume infall.

Safety and effectiveness of stem cell therapies in early-phase clinical trials in stroke: a systematic review and meta-analysis.

PubMed

Nagpal, Anjali; Choy, Fong Chan; Howell, Stuart; Hillier, Susan; Chan, Fiona; Hamilton-Bruce, Monica A; Koblar, Simon A

2017-08-30

Stem cells have demonstrated encouraging potential as reparative therapy for patients suffering from post-stroke disability. Reperfusion interventions in the acute phase of stroke have shown significant benefit but are limited by a narrow window of opportunity in which they are beneficial. Thereafter, rehabilitation is the only intervention available. The current review summarises the current evidence for use of stem cell therapies in stroke from early-phase clinical trials. The safety and feasibility of administering different types of stem cell therapies in stroke seem to be reasonably proven. However, the effectiveness needs still to be established through bigger clinical trials with more pragmatic clinical trial designs that address the challenges raised by the heterogeneous nature of stroke per se, as well those due to unique characteristics of stem cells as therapeutic agents.

Rhythm and interpersonal synchrony in early social development.

PubMed

Trainor, Laurel J; Cirelli, Laura

2015-03-01

Adults who engage in synchronous movement to music later report liking each other better, remembering more about each other, trusting each other more, and are more likely to cooperate with each other compared to adults who engage in asynchronous movements. Although poor motor coordination limits infants' ability to entrain to a musical beat, they perceive metrical structure in auditory rhythm patterns, their movements are affected by the tempo of music they hear, and if they are bounced by an adult to a rhythm pattern, the manner of this bouncing can affect their auditory interpretation of the meter of that pattern. In this paper, we review studies showing that by 14 months of age, infants who are bounced in synchrony with an adult subsequently show more altruistic behavior toward that adult in the form of handing back objects "accidentally" dropped by the adult compared to infants who are bounced asynchronously with the adult. Furthermore, increased helpfulness is directed at the synchronized bounce partner, but not at a neutral stranger. Interestingly, however, helpfulness does generalize to a "friend" of the synchronized bounce partner. In sum, synchronous movement between infants and adults has a powerful effect on infants' expression of directed prosocial behavior. © 2014 New York Academy of Sciences.

Challenges and perspective of drug repurposing strategies in early phase clinical trials.

PubMed

Kato, Shumei; Moulder, Stacy L; Ueno, Naoto T; Wheler, Jennifer J; Meric-Bernstam, Funda; Kurzrock, Razelle; Janku, Filip

2015-01-01

Despite significant investments in the development of new agents only 5% of cancer drugs entering Phase I clinical trials are ultimately approved for routine clinical cancer care. Drug repurposing strategies using novel combinations of previously tested anticancer agents could reduce the cost and improve treatment outcomes. At MD Anderson Cancer Center, early phase clinical trials with drug repurposing strategies demonstrated promising outcomes in patients with both rare and common treatment refractory advanced cancers. Despite clinical efficacy advancing drug repurposing strategies in the clinical trial trajectory beyond early phase studies has been challenging mainly due to lack of funding and interest from the pharmaceutical industry. In this review, we delineate our experience and challenges with drug repurposing strategies.

The Great East Japan Earthquake: a need to plan for post-disaster surveillance in developed countries

PubMed Central

Matsui, Tamano; Partridge, Jeffrey; Kasai, Takeshi

2011-01-01

After a devastating earthquake and tsunami struck north-eastern Japan in March 2011, the public health system, including the infectious disease surveillance system, was severely compromised. While models for post-disaster surveillance exist, they focus predominantly on developing countries during the early recovery phase. Such models do not necessarily apply to developed countries, which differ considerably in their baseline surveillance systems. Furthermore, there is a need to consider the process by which a surveillance system recovers post-disaster. The event in Japan has highlighted a need to address these concerns surrounding post-disaster surveillance in developed countries. In May 2011, the World Health Organization convened a meeting where post-disaster surveillance was discussed by experts and public health practitioners. In this paper, we describe a post-disaster surveillance approach that was discussed at the meeting, based on what had actually occurred and what may have been, or would be, ideal. Briefly, we describe the evolution of a surveillance system as it returns to the pre-existing system, starting from an event-based approach during the emergency relief phase, a syndromic approach during the early recovery phase, an enhanced sentinel approach during the late recovery phase and a return to baseline during the development phase. Our aim is not to recommend a specific model but to encourage other developed countries to initiate their own discussions on post-disaster surveillance and develop plans according to their needs and capacities. As natural disasters will continue to occur, we hope that developing such plans during the “inter-disaster” period will help mitigate the surveillance challenges that will arise post-disaster. PMID:23908893

Post-disaster health impact of natural hazards in the Philippines in 2013.

PubMed

Salazar, Miguel Antonio; Pesigan, Arturo; Law, Ronald; Winkler, Volker

2016-01-01

In 2011, the Health Emergency Management Bureau (HEMB) created the Surveillance for Post Extreme Emergencies and Disasters (SPEED), a real-time syndromic surveillance system that allows the early detection and monitoring of post-disaster disease trends. SPEED can assist health leaders in making informed decisions on health systems affected by disasters. There is a need for further validation of current concepts in post-disaster disease patterns in respect to actual field data. This study aims to evaluate the temporal post-disaster patterns of selected diseases after a flood, an earthquake, and a typhoon in the Philippines in 2013. We analyzed the 21 syndromes provided by SPEED both separately and grouped into injuries, communicable diseases, and non-communicable diseases (NCDs) by calculating daily post-disaster consultation rates for up to 150 days post-disaster. These were compared over time and juxtaposed according to the type of disaster. Communicable diseases were found to be the predominant syndrome group in all three disaster types. The top six syndromes found were: acute respiratory infections, open wounds, bruises and burns, high blood pressure, skin disease, fever, and acute watery diarrhea. Overall, the results aligned with the country's morbidity profile. Within 2 months, the clear gradation of increasing syndrome rates reflected the severity (floodphase. The most common syndromes can be addressed by measures such as providing for shelter, water, sanitation, hygiene, nutrition, and common health services. Most post-disaster syndromes may be addressed by prevention, early diagnosis, and early treatment. Health needs differ in response and recovery phases.

Rotigotine in Combination with the MAO-B Inhibitor Selegiline in Early Parkinson’s Disease: A Post Hoc Analysis

PubMed Central

Giladi, Nir; Asgharnejad, Mahnaz; Bauer, Lars; Grieger, Frank; Boroojerdi, Babak

2016-01-01

Background: Monoamine oxidase B (MAO-B) inhibitors and dopamine receptor agonists are common first-line treatment options in early Parkinson’s disease (PD). Objective: To evaluate the efficacy and safety of rotigotine transdermal patch as an add-on therapy to an MAO-B inhibitor in patients with early-PD. Methods: In two Phase III, randomized, double-blind, placebo-controlled studies in early-PD (SP512, SP513), patients were randomized to rotigotine (titrated to optimal dose ≤8 mg/24 h) or placebo, and maintained for 24 (SP512) or 33 (SP513) weeks. Post hoc analyses were performed on pooled data for patients receiving an MAO-B inhibitor (selegiline) at a stable dose at randomization and throughout the studies, with groups defined as “Selegiline+Rotigotine” and “Selegiline+Placebo”. Outcome measures included change from baseline in Unified Parkinson’s Disease Rating Scale (UPDRS) II (activities of daily living), III (motor), UPDRS II+III and responders (patients achieving ≥20%, ≥25% or ≥30% decrease in UPDRS II+III). As post hoc analyses, p-values are exploratory. Results: 130 patients were evaluable for efficacy analyses (“Selegiline+Rotigotine”: 84, “Selegiline+Placebo”: 46). Combined treatment with rotigotine and selegiline improved UPDRS III and UPDRS II+III scores versus selegiline alone (LS-mean [95% CI] treatment difference for UPDRS III: –4.89 [–7.87 to –1.91], p = 0.0015; for UPDRS II+III: –5.76 [–9.71 to –1.82], p = 0.0045). Higher proportion of patients in the “Selegiline+Rotigotine” group were classified as ≥20%, ≥25% or ≥30% responders (all p < 0.001). Combined treatment appeared more effective in patients aged ≤65 years versus > 65 years (although patient numbers in the subgroups were low). Adverse event profile was consistent with the known safety profile of rotigotine. Conclusions: In these post hoc analyses, adjunctive treatment with rotigotine in patients already receiving an

Early post-fire succession in California chaparral: changes in diversity, density, cover, and biomass

USGS Publications Warehouse

Guo, Q.

2001-01-01

For four consecutive years, following the fires in November 1993, temporal variations in species richness, cover and biomass of component plant groups in early post-fire chaparral succession were monitored on different aspects at the Stunt Ranch Santa Monica Mountains Reserve, southern California. Plant groups were categorized based on growth form, life form, ability to fix nitrogen, geographic origin and regeneration strategies. North-facing slopes exhibited higher species richness, higher species turnover rate over time and faster vegetation recovery in terms of biomass accumulation and return to pre-fire species composition. This was probably due to higher species richness and biomass of nitrogen-fixing species found on north-facing slopes in comparison to south-facing slopes. On both north- and south-facing slopes, annuals had the highest species turnover rate, followed by herbaceous perennials and shrubs. In the first four post-fire years, annual species were the largest floristic group, but herbaceous perennials and shrubs were the major contributors to community biomass. Nitrogen-fixing species and exotics contributed significantly to early post-fire community structure. Although the general trends in post-fire succession are clear in terms of temporal changes in the relative proportions of different plant groups, environmental variation and the nature of plant life histories of component species, especially dominant species, could alter such trends significantly.

Early post-fire succession in California chaparral: Changes in diversity, density, cover and biomass

USGS Publications Warehouse

Guo, Q.

2001-01-01

For four consecutive years, following the fires in November 1993, temporal variations in species richness, cover and biomass of component plant groups in early post-fire chaparral succession were monitored on different aspects at the Stunt Ranch Santa Monica Mountains Reserve, southern California. Plant groups were categorized based on growth form, life form, ability to fix nitrogen, geographic origin and regeneration strategies. North-facing slopes exhibited higher species richness, higher species turnover rate over time and faster vegetation recovery in terms of biomass accumulation and return to pre-fire species composition. This was probably due to higher species richness and biomass of nitrogen-fixing species found on north-facing slopes in comparison to south-facing slopes. On both north- and south-facing slopes, annuals had the highest species turnover rate, followed by herbaceous perennials and shrubs. In the first four post-fire years, annual species were the largest floristic group, but herbaceous perennials and shrubs were the major contributors to community biomass. Nitrogen-fixing species and exotics contributed significantly to early post-fire community structure. Although the general trends in post-fire succession are clear in terms of temporal changes in the relative proportions of different plant groups, environmental variation and the nature of plant life histories of component species, especially dominant species, could alter such trends significantly.

Early post-stroke cognition in stroke rehabilitation patients predicts functional outcome at 13 months.

PubMed

Wagle, Jørgen; Farner, Lasse; Flekkøy, Kjell; Bruun Wyller, Torgeir; Sandvik, Leiv; Fure, Brynjar; Stensrød, Brynhild; Engedal, Knut

2011-01-01

To identify prognostic factors associated with functional outcome at 13 months in a sample of stroke rehabilitation patients. Specifically, we hypothesized that cognitive functioning early after stroke would predict long-term functional outcome independently of other factors. 163 stroke rehabilitation patients underwent a structured neuropsychological examination 2-3 weeks after hospital admittance, and their functional status was subsequently evaluated 13 months later with the modified Rankin Scale (mRS) as outcome measure. Three predictive models were built using linear regression analyses: a biological model (sociodemographics, apolipoprotein E genotype, prestroke vascular factors, lesion characteristics and neurological stroke-related impairment); a functional model (pre- and early post-stroke cognitive functioning, personal and instrumental activities of daily living, ADL, and depressive symptoms), and a combined model (including significant variables, with p value <0.05, from the biological and functional models). A combined model of 4 variables best predicted long-term functional outcome with explained variance of 49%: neurological impairment (National Institute of Health Stroke Scale; β = 0.402, p < 0.001), age (β = 0.233, p = 0.001), post-stroke cognitive functioning (Repeatable Battery of Neuropsychological Status, RBANS; β = -0.248, p = 0.001) and prestroke personal ADL (Barthel Index; β = -0.217, p = 0.002). Further linear regression analyses of which RBANS indexes and subtests best predicted long-term functional outcome showed that Coding (β = -0.484, p < 0.001) and Figure Copy (β = -0.233, p = 0.002) raw scores at baseline explained 42% of the variance in mRS scores at follow-up. Early post-stroke cognitive functioning as measured by the RBANS is a significant and independent predictor of long-term functional post-stroke outcome. Copyright © 2011 S. Karger AG, Basel.

1.2 MW peak power, all-solid-state picosecond laser with a microchip laser seed and a high gain single-passing bounce geometry amplifier

NASA Astrophysics Data System (ADS)

Wang, Chunhua; Shen, Lifeng; Zhao, Zhiliang; Liu, Bin; Jiang, Hongbo; Chen, Jun; Liu, Chong

2016-11-01

A semiconductor saturable absorber mirror (SESAM) based passively Q-switched microchip Nd:YVO4 seed laser with pulse duration of 90 ps at repetition rate of 100 kHz is amplified by single-passing a Nd:YVO4 bounce amplifier with varying seed input power from 20 μW to 10 mW. The liquid pure metal greasy thermally conductive material is used to replace the traditional thin indium foil as the thermal contact material for better heat load transfer of the Nd:YVO4 bounce amplifier. Temperature distribution at the pump surface is measured by an infrared imager to compare with the numerically simulated results. A highest single-passing output power of 11.3 W is obtained for 10 mW averaged seed power, achieving a pulse peak power of ~1.25 MW and pulse energy of ~113 μJ. The beam quality is well preserved with M2 ≤1.25. The simple configuration of this bounce laser amplifier made the system flexible, robust and cost-effective, showing attractive potential for further applications.

Very Early Colorectal Anastomotic Leakage within 5 Post-operative Days: a More Severe Subtype Needs Relaparatomy

PubMed Central

Li, Yi-Wei; Lian, Peng; Huang, Ben; Zheng, Hong-Tu; Wang, Ming-He; Gu, Wei-Lie; Li, Xin-Xiang; Xu, Ye; Cai, San-Jun

2017-01-01

Early anastomotic leakage (AL), usually defined as leakage within 30 post-operative days, represents a severe entity. However, mounting evidence has indicated that majorities of leakage occur within one week after surgery, making late AL rarity. Here we analyzed 101 consecutive colorectal AL, all of which occurred within 30 post-operative days, during Jan 2013 and Dec 2015 in cancer hospital of Fudan University. AL occurring within 5 post-operative days was defined as very early AL (vE-AL). We evaluated risk factors of vE-AL compared with non-vEAL and correlated with post-leakage peritonitis and need of relaparatomy. We found that AL occurred at median time of 7 days after surgery. 23 cases were vE-AL. Reconstruction of post-peritoneum for mid-low rectal carcinoma significantly reduced incidence of vE-AL compared with non-vE-AL (p = 0.042). Patients with vE-AL was associated with presence of peritonitis (p = 0.031), the latter significantly correlated with increased re-operation rate (p = 6.8E-13). Besides, patients with vE-AL trended to correlate with increased re-operation rate after leakage (p = 0.088). In concludsion, vE-AL occurring within 5 post-operative days represents a severe subtype associated with general peritonitis and need of relaparatomy. PMID:28084305

Slowing extrusion tectonics: Lowered estimate of post-Early Miocene slip rate for the Altyn Tagh fault

USGS Publications Warehouse

Yue, Y.; Ritts, B.D.; Graham, S.A.; Wooden, J.L.; Gehrels, G.E.; Zhang, Z.

2004-01-01

Determination of long-term slip rate for the Altyn Tagh fault is essential for testing whether Asian tectonics is dominated by lateral extrusion or distributed crustal shortening. Previous slip-history studies focused on either Quaternary slip-rate measurements or pre-Early Miocene total-offset estimates and do not allow a clear distinction between rates based on the two. The magmatic and metamorphic history revealed by SHRIMP zircon dating of clasts from Miocene conglomerate in the Xorkol basin north of the Altyn Tagh fault strikingly matches that of basement in the southern Qilian Shan and northern Qaidam regions south of the fault. This match requires that the post-Early Miocene long-term slip rate along the Altyn Tagh fault cannot exceed 10 mm/year, supporting the hypothesis of distributed crustal thickening for post-Early Miocene times. This low long-term slip rate and recently documented large pre-Early Miocene cumulative offset across the fault support a two-stage evolution, wherein Asian tectonics was dominated by lateral extrusion before the end of Early Miocene, and since then has been dominated by distributed crustal thickening and rapid plateau uplift. ?? 2003 Elsevier B.V. All rights reserved.

Weight-related self-efficacy in relation to maternal body weight from early pregnancy to 2 years post-partum

PubMed Central

Lipsky, Leah M.; Strawderman, Myla S.; Olson, Christine M.

2016-01-01

Excessive gestational weight gain may lead to long-term increases in maternal body weight and associated health risks. The purpose of this study was to examine the relationship between maternal body weight and weight-related self-efficacy from early pregnancy to 2 years post-partum. Women with live, singleton term infants from a population-based cohort study were included (n = 595). Healthy eating self-efficacy and weight control self-efficacy were assessed prenatally and at 1 year and 2 years post-partum. Body weight was measured at early pregnancy, before delivery, and 6 weeks, 1 year and 2 years post-partum. Behavioural (smoking, breastfeeding) and sociodemographic (age, education, marital status, income) covariates were assessed by medical record review and baseline questionnaires. Multi-level linear regression models were used to examine the longitudinal associations of self-efficacy measures with body weight. Approximately half of the sample (57%) returned to early pregnancy weight at some point by 2 years post-partum, and 9% became overweight or obese at 2 years post-partum. Body weight over time was inversely related to healthy eating (β = −0.57, P = 0.02) and weight control (β = −0.99, P < 0.001) self-efficacy in the model controlling for both self-efficacy measures as well as time and behavioural and sociodemographic covariates. Weight-related self-efficacy may be an important target for interventions to reduce excessive gestational weight gain and post-partum weight gain. PMID:25244078

Post-recombination early Universe cooling by translation-internal inter-conversion: The role of minor constituents.

PubMed

McCaffery, Anthony J

2015-09-14

Little is known of the mechanism by which H and H2, the principal constituents of the post-re-combination early Universe, cooled sufficiently to permit cluster formation, nucleosynthesis, and, eventually, the formation of structured objects. Radiative decay primarily cools the internal modes of H2, as Δj = - 2 jumps accompany quadrupolar emission. This, however, would be a self-limiting mechanism. In this work, a translational energy cooling mechanism based on collision-induced, translation-to-internal mode conversion, is extended, following an earlier study [A. J. McCaffery and R. J. Marsh, J. Chem. Phys. 139, 234310 (2013)] of ensembles comprising H2 in a H atom bath gas. Here, the possible influence of minor species, such as HD, on this cooling mechanism is investigated. Results suggest that the influence of HD is small but not insignificant. Conversion is very rapid and an overall translation-to-internal energy conversion efficiency of some 5% could be expected. This finding may be of use in the further development of models of this complex phase of early Universe evolution. An unexpected finding in this study was that H2 + HD ensembles are capable of very rapid translation-to-internal conversion with efficiencies of >40% and relaxation rates that appear to be relatively slow. This may have potential as an energy storage mechanism.

Post-recombination early Universe cooling by translation–internal inter-conversion: The role of minor constituents

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCaffery, Anthony J., E-mail: A.J.McCaffery@sussex.ac.uk

Little is known of the mechanism by which H and H{sub 2}, the principal constituents of the post-re-combination early Universe, cooled sufficiently to permit cluster formation, nucleosynthesis, and, eventually, the formation of structured objects. Radiative decay primarily cools the internal modes of H{sub 2}, as Δj = − 2 jumps accompany quadrupolar emission. This, however, would be a self-limiting mechanism. In this work, a translational energy cooling mechanism based on collision-induced, translation-to-internal mode conversion, is extended, following an earlier study [A. J. McCaffery and R. J. Marsh, J. Chem. Phys. 139, 234310 (2013)] of ensembles comprising H{sub 2} in amore » H atom bath gas. Here, the possible influence of minor species, such as HD, on this cooling mechanism is investigated. Results suggest that the influence of HD is small but not insignificant. Conversion is very rapid and an overall translation-to-internal energy conversion efficiency of some 5% could be expected. This finding may be of use in the further development of models of this complex phase of early Universe evolution. An unexpected finding in this study was that H{sub 2} + HD ensembles are capable of very rapid translation-to-internal conversion with efficiencies of >40% and relaxation rates that appear to be relatively slow. This may have potential as an energy storage mechanism.« less

Cytokine expression during early and late phase of acute Puumala hantavirus infection

PubMed Central

2011-01-01

Background Hantaviruses of the family Bunyaviridae are emerging zoonotic pathogens which cause hemorrhagic fever with renal syndrome (HFRS) in the Old World and hantavirus pulmonary syndrome (HPS) in the New World. An immune-mediated pathogenesis is discussed for both syndromes. The aim of our study was to investigate cytokine expression during the course of acute Puumala hantavirus infection. Results We retrospectively studied 64 patients hospitalised with acute Puumala hantavirus infection in 2010 during a hantavirus epidemic in Germany. Hantavirus infection was confirmed by positive anti-hantavirus IgG/IgM. Cytokine expression of IL-2, IL-5, IL-6, IL-8, IL-10, IFN-γ, TNF-α and TGF-β1 was analysed by ELISA during the early and late phase of acute hantavirus infection (average 6 and 12 days after onset of symptoms, respectively). A detailed description of the demographic and clinical presentation of severe hantavirus infection requiring hospitalization during the 2010 hantavirus epidemic in Germany is given. Acute hantavirus infection was characterized by significantly elevated levels of IL-2, IL-6, IL-8, TGF-β1 and TNF-α in both early and late phase compared to healthy controls. From early to late phase of disease, IL-6, IL-10 and TNF-α significantly decreased whereas TGF-β1 levels increased. Disease severity characterized by elevated creatinine and low platelet counts was correlated with high pro-inflammatory IL-6 and TNF-α but low immunosuppressive TGF-β1 levels and vice versa . Conclusion High expression of cytokines activating T-lymphocytes, monocytes and macrophages in the early phase of disease supports the hypothesis of an immune-mediated pathogenesis. In the late phase of disease, immunosuppressive TGF-β1 level increase significantly. We suggest that delayed induction of a protective immune mechanism to downregulate a massive early pro-inflammatory immune response might contribute to the pathologies characteristic of human hantavirus infection

Reliability of bounce drop jump parameters within elite male rugby players.

PubMed

Costley, Lisa; Wallace, Eric; Johnston, Michael; Kennedy, Rodney

2017-07-25

The aims of the study were to investigate the number of familiarisation sessions required to establish reliability of the bounce drop jump (BDJ) and subsequent reliability once familiarisation is achieved. Seventeen trained male athletes completed 4 BDJs in 4 separate testing sessions. Force-time data from a 20 cm BDJ was obtained using two force plates (ensuring ground contact < 250 ms). Subjects were instructed to 'jump for maximal height and minimal contact time' while the best and average of four jumps were compared. A series of performance variables were assessed in both eccentric and concentric phases including jump height, contact time, flight time, reactive strength index (RSI), peak power, rate of force development (RFD) and actual dropping height (ADH). Reliability was assessed using the intraclass correlation coefficient (ICC) and coefficient of variation (CV) while familiarisation was assessed using a repeated measures analysis of variance (ANOVA). The majority of DJ parameters exhibited excellent reliability with no systematic bias evident, while the average of 4 trials provided greater reliability. With the exception of vertical stiffness (CV: 12.0 %) and RFD (CV: 16.2 %) all variables demonstrated low within subject variation (CV range: 3.1 - 8.9 %). Relative reliability was very poor for ADH, with heights ranging from 14.87 - 29.85 cm. High levels of reliability can be obtained from the BDJ with the exception of vertical stiffness and RFD, however, extreme caution must be taken when comparing DJ results between individuals and squads due to large discrepancies between actual drop height and platform height.

NKCC1 up-regulation contributes to early post-traumatic seizures and increased post-traumatic seizure susceptibility.

PubMed

Wang, Fushun; Wang, Xiaowei; Shapiro, Lee A; Cotrina, Maria L; Liu, Weimin; Wang, Ernest W; Gu, Simeng; Wang, Wei; He, Xiaosheng; Nedergaard, Maiken; Huang, Jason H

2017-04-01

Traumatic brain injury (TBI) is not only a leading cause for morbidity and mortality in young adults (Bruns and Hauser, Epilepsia 44(Suppl 10):210, 2003), but also a leading cause of seizures. Understanding the seizure-inducing mechanisms of TBI is of the utmost importance, because these seizures are often resistant to traditional first- and second-line anti-seizure treatments. The early post-traumatic seizures, in turn, are a contributing factor to ongoing neuropathology, and it is critically important to control these seizures. Many of the available anti-seizure drugs target gamma-aminobutyric acid (GABA A ) receptors. The inhibitory activity of GABA A receptor activation depends on low intracellular Cl - , which is achieved by the opposing regulation of Na + -K + -Cl - cotransporter 1 (NKCC1) and K + -Cl - -cotransporter 2 (KCC2). Up-regulation of NKCC1 in neurons has been shown to be involved in neonatal seizures and in ammonia toxicity-induced seizures. Here, we report that TBI-induced up-regulation of NKCC1 and increased intracellular Cl - concentration. Genetic deletion of NKCC1 or pharmacological inhibition of NKCC1 with bumetanide suppresses TBI-induced seizures. TGFβ expression was also increased after TBI and competitive antagonism of TGFβ reduced NKKC1 expression, ameliorated reactive astrocytosis, and inhibited seizures. Thus, TGFβ might be an important pathway involved in NKCC1 up-regulation after TBI. Our findings identify neuronal up-regulation of NKCC1 and its mediation by TGFβ, as a potential and important mechanism in the early post-traumatic seizures, and demonstrate the therapeutic potential of blocking this pathway.

Phase III Early Restoration Meeting - Galveston, TX | NOAA Gulf Spill

Science.gov Websites

Areas Alabama Florida Louisiana Mississippi Texas Region-wide Open Ocean Data Media & News planning for Phase III and future early restoration plans. Open House: 6:00pm Public Meeting: 6:30pm

Critical role of STIR MRI in early detection of post-streptococcal periostitis with dysproteinaemia (Goldbloom's syndrome).

PubMed

Papa, Riccardo; Consolaro, Alessandro; Minoia, Francesca; Caorsi, Roberta; Magnano, Gianmichele; Gattorno, Marco; Ravelli, Angelo; Picco, Paolo

2017-01-01

In 1966, Goldbloom et al. described two children who developed a peculiar clinical picture characterized by intermittent daily bone pain in the lower limbs, fever spikes, increased acute phase reactants and dysproteinaemia. The syndrome occurred two weeks after a group A β-haemolytic streptococcus infection. So far, only a few cases have been reported in the medical literature in English. We report two further cases of Goldbloom's syndrome with a review of the literature in English. Our two patients lived in the same Italian region and presented their syndrome onset a week apart. Early use of STIR MRI revealed an atypical metaphyseal hyperintensity in the femurs and tibias. X-ray showed periosteal hyperostosis. A short cycle of corticosteroids led to rapid recovery of symptoms and disappearance of bone changes. The reported cases highlight a likely under-recognised post-streptococcal inflammatory periosteal reaction and emphasise the diagnostic utility of the newer imaging modalities.

Impact of incretin on early-phase insulin secretion and glucose excursion.

PubMed

Shen, Jie; Chen, Zhi; Chen, Chaofeng; Zhu, Xiao; Han, Yajuan

2013-10-01

This study investigated the impact of incretin on early-phase insulin secretion and glucose excursion. The normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and type 2 diabetes mellitus (T2DM) groups included 16, 8, and 19 subjects, respectively. Subjects underwent continuous glucose monitoring for 3 days, followed by an oral glucose tolerance test. Plasma glucose, insulin, glucagon, total glucose-dependent insulinotropic polypeptide (GIP), and glucagon-like peptide-l (GLP-1) levels were measured at 30-min increments for 2 h after glucose intake. Differences with P < 0.05 were considered statistically significant. The area under the curve (AUC) of total GIP (120-min GIP-AUC) of the T2DM group was significantly lower than those of the NGT and IGT groups. The 120-min GLP-1-AUC of the NGT group was significantly larger than those of the T2DM and IGT groups. The early-phase insulin secretion index (ΔI30/ΔG30) of the T2DM group was significantly lower than those of the NGT and IGT groups. Mean amplitudes of glycemic excursions (MAGEs) went in the order of NGT < IGT < T2DM (P < 0.01, IGT vs. NGT; P < 0.001, T2DM vs. IGT). The 120-min GIP-AUC was negatively correlated with MAGE (r = -0.464), but uncorrelated with ΔI30/ΔG30. The 120-min GLP-1-AUC was positively correlated with ΔI30/ΔG30 (r = 0.580), but negatively correlated with MAGE (r = -0.606). Incretin may ameliorate glucose excursions, and GLP-1 may exert them by promoting early-phase insulin secretion. No correlation was observed between GIP secretion and early-phase insulin secretion.

Early initiation of post-sternotomy cardiac rehabilitation exercise training (SCAR): study protocol for a randomised controlled trial and economic evaluation

PubMed Central

Lobley, Grace; Worrall, Sandra; Powell, Richard; Kimani, Peter K; Banerjee, Prithwish; Barker, Thomas

2018-01-01

Introduction Current guidelines recommend abstinence from supervised cardiac rehabilitation (CR) exercise training for 6 weeks post-sternotomy. This practice is not based on empirical evidence, thus imposing potentially unnecessary activity restrictions. Delayed participation in CR exercise training promotes muscle atrophy, reduces cardiovascular fitness and prolongs recovery. Limited data suggest no detrimental effect of beginning CR exercise training as early as 2 weeks post-surgery, but randomised controlled trials are yet to confirm this. The purpose of this trial is to compare CR exercise training commenced early (2 weeks post-surgery) with current usual care (6 weeks post-surgery) with a view to informing future CR guidelines for patients recovering from sternotomy. Methods and analysis In this assessor-blind randomised controlled trial, 140 cardiac surgery patients, recovering from sternotomy, will be assigned to 8 weeks of twice-weekly supervised CR exercise training commencing at either 2 weeks (early CR) or 6 weeks (usual care CR) post-surgery. Usual care exercise training will adhere to current UK recommendations. Participants in the early CR group will undertake a highly individualised 2–3 week programme of functional mobility, strength and cardiovascular exercise before progressing to a usual care CR programme. Outcomes will be assessed at baseline (inpatient), pre-CR (2 or 6 weeks post-surgery), post-CR (10 or 14 weeks post-surgery) and 12 months. The primary outcome will be change in 6 min walk distance. Secondary outcomes will include measures of functional fitness, quality of life and cost-effectiveness. Ethics and dissemination Recruitment commenced on July 2017 and will complete by December 2019. Results will be disseminated via national governing bodies, scientific meetings and peer-reviewed journals. Trial registration number NCT03223558; Pre-results. PMID:29574443

Non-singular Brans–Dicke collapse in deformed phase space

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rasouli, S.M.M., E-mail: mrasouli@ubi.pt; Centro de Matemática e Aplicações; Physics Group, Qazvin Branch, Islamic Azad University, Qazvin

2016-12-15

We study the collapse process of a homogeneous perfect fluid (in FLRW background) with a barotropic equation of state in Brans–Dicke (BD) theory in the presence of phase space deformation effects. Such a deformation is introduced as a particular type of non-commutativity between phase space coordinates. For the commutative case, it has been shown in the literature (Scheel, 1995), that the dust collapse in BD theory leads to the formation of a spacetime singularity which is covered by an event horizon. In comparison to general relativity (GR), the authors concluded that the final state of black holes in BD theorymore » is identical to the GR case but differs from GR during the dynamical evolution of the collapse process. However, the presence of non-commutative effects influences the dynamics of the collapse scenario and consequently a non-singular evolution is developed in the sense that a bounce emerges at a minimum radius, after which an expanding phase begins. Such a behavior is observed for positive values of the BD coupling parameter. For large positive values of the BD coupling parameter, when non-commutative effects are present, the dynamics of collapse process differs from the GR case. Finally, we show that for negative values of the BD coupling parameter, the singularity is replaced by an oscillatory bounce occurring at a finite time, with the frequency of oscillation and amplitude being damped at late times.« less

Non-singular Brans-Dicke collapse in deformed phase space

NASA Astrophysics Data System (ADS)

Rasouli, S. M. M.; Ziaie, A. H.; Jalalzadeh, S.; Moniz, P. V.

2016-12-01

We study the collapse process of a homogeneous perfect fluid (in FLRW background) with a barotropic equation of state in Brans-Dicke (BD) theory in the presence of phase space deformation effects. Such a deformation is introduced as a particular type of non-commutativity between phase space coordinates. For the commutative case, it has been shown in the literature (Scheel, 1995), that the dust collapse in BD theory leads to the formation of a spacetime singularity which is covered by an event horizon. In comparison to general relativity (GR), the authors concluded that the final state of black holes in BD theory is identical to the GR case but differs from GR during the dynamical evolution of the collapse process. However, the presence of non-commutative effects influences the dynamics of the collapse scenario and consequently a non-singular evolution is developed in the sense that a bounce emerges at a minimum radius, after which an expanding phase begins. Such a behavior is observed for positive values of the BD coupling parameter. For large positive values of the BD coupling parameter, when non-commutative effects are present, the dynamics of collapse process differs from the GR case. Finally, we show that for negative values of the BD coupling parameter, the singularity is replaced by an oscillatory bounce occurring at a finite time, with the frequency of oscillation and amplitude being damped at late times.

Visualization of early post-implantation mouse embryogenesis using 3D imaging modality (Conference Presentation)

NASA Astrophysics Data System (ADS)

Hsu, Chih-Wei; Le, Henry H.; Li-Villarreal, Nanbing; Piazza, Victor G.; Kalaga, Sowmya; Dickinson, Mary E.

2017-02-01

Hemodynamic force is vital to cardiovascular remodeling in the early post-implantation mouse embryo. Here, we present work using microCT and lightsheet microscopy to establish the critical sequence of developmental events required for forming functional vasculature and circulation in the embryo, yolk sac, and placenta in the context of normal and impaired flow. A flow impaired model, Mlc2a+/- will be used to determine how hemodynamic force affects the specific events during embryonic development and vascular remodeling between the 4 and 29-somite stage using microCT. We have recently established high-resolution methods for the generation of 3D image volumes from the whole embryo within the deciduum (Hsu et al., in revision). This method enables the careful characterization of 3D images of vitelline and umbilical vessel remodeling to define how poor blood flow impacts both vitelline and umbilical vessel remodeling. Novel lightsheet live imaging techniques will be used to determine the consequence of impaired blood flow on yolk sac vasculature remodeling and formation of umbilical vessels using transgenic reporters: Flk-myr::mCherry, Flk1-H2B::YFP, or ɛGlobin-GFP. High-resolution 3D imaging of fixed and ScaleA2-cleared whole mount embryos labeled with Ki67 and Caspase3 will also be performed using lightsheet microscopy to quantify the proliferation and apoptotic indexes of early post-implanted embryos and yolk sac. This multi-modality approach is aimed at revealing further information about the cellular mechanisms required for proper vessel remodeling and the initial stages in placentation during early post-implantation development.

Weight-related self-efficacy in relation to maternal body weight from early pregnancy to 2 years post-partum.

PubMed

Lipsky, Leah M; Strawderman, Myla S; Olson, Christine M

2016-07-01

Excessive gestational weight gain may lead to long-term increases in maternal body weight and associated health risks. The purpose of this study was to examine the relationship between maternal body weight and weight-related self-efficacy from early pregnancy to 2 years post-partum. Women with live, singleton term infants from a population-based cohort study were included (n = 595). Healthy eating self-efficacy and weight control self-efficacy were assessed prenatally and at 1 year and 2 years post-partum. Body weight was measured at early pregnancy, before delivery, and 6 weeks, 1 year and 2 years post-partum. Behavioural (smoking, breastfeeding) and sociodemographic (age, education, marital status, income) covariates were assessed by medical record review and baseline questionnaires. Multi-level linear regression models were used to examine the longitudinal associations of self-efficacy measures with body weight. Approximately half of the sample (57%) returned to early pregnancy weight at some point by 2 years post-partum, and 9% became overweight or obese at 2 years post-partum. Body weight over time was inversely related to healthy eating (β = -0.57, P = 0.02) and weight control (β = -0.99, P < 0.001) self-efficacy in the model controlling for both self-efficacy measures as well as time and behavioural and sociodemographic covariates. Weight-related self-efficacy may be an important target for interventions to reduce excessive gestational weight gain and post-partum weight gain. © 2014 John Wiley & Sons Ltd.

Do mature forest birds prefer early-successional habitat during the post-fledging period?

Treesearch

Carlin C. Chandler; David I. King; Richard B. Chandler

2012-01-01

Recent studies have highlighted the importance of the post-fledging period to bird populations, suggesting that the importance of this portion of the life cycle is equal to or greater than the nesting period. Nevertheless, few studies have compared abundance of forest nesting species between mature forest and early-successional habitats while controlling for...

Phase equilibria and velocity discontinuities across the post-perovskite transition in (Mg,Fe)SiO3

NASA Astrophysics Data System (ADS)

Wentzcovitch, Renata; Shukla, Gaurav; Sarkar, Kanchan

The enigmatic nature of the region above the Earth's core-mantle boundary known as the D'' region, is often characterized by a significant contrast in seismic wave velocities. The perovskite (Pv) to post-perovskite (PPv) transition in bridgmanite ((Mg,Fe)SiO3 perovskite) is one of the keys for understanding this region. In this study, we present DFT + USC calculations of phase equilibria in bridgmanite across the post-perovskite transition. Thermal effects are addressed within the quasi-harmonic approximation. By computing high-pressure and high-temperatures elastic/acoustic properties of Pv and PPv phases, we also investigate seismic signature of the PPv-transition, believed to cause the D'' discontinuity. Aggregate elastic moduli and sound velocities for the Mg-end member are successfully compared with limited experimental data available. Predicted velocity discontinuities across the PPv transition are consistent with seismic observations in some places of the global D'' discontinuity. Our robust estimates of the phase boundary and elastic properties of the perovskite and post-perovskite phases will help to clarify the origin of lateral velocity variations in the deep lower mantle region and constrain its composition and thermal structure. 1This research was supported primarily by NSF Grants EAR 1348066 and DMR 1503084. Computations are performed at the Minnesota Su- percomputing Institute (MSI).

Early Risk Reduction Phase 1 FLIR/Laser Designator Window. Revision

DTIC Science & Technology

1991-12-31

Sandwich-Type FLIR Windows," Air Force AFWAL-TR-83- 4122, Nov 1983. 4-1 Hughes Danbury Optical Systems Final Report, "ATA Window Technology Program," PRBll...Risk Reduction -- Phase I, Optical Properties Measurement Techniques of Three Wide Band Window Materials," 22 August 1991. xii I i 86PR0869 30... Optical Systems, Lexington, MA, 02173, 1 Feb 1991. 5-7 McDonnell Aircraft Company Technical Memorandum TM 256.91.0056.01, "Early Risk Reduction -- Phase

Bouncing Back From War Trauma: Resiliency in Global War on Terror’s Wounded Warriors

DTIC Science & Technology

2015-02-11

Casualties of the Global War on Terror and Their Future Impact on Health Care and Society: A Looming Public Health Crisis .” Military Medicine 179 (April...Casualties of the Global War on Terror and Their Future Impact on Health Care and Society: A Looming Public Health Crisis .” Military Medicine 179...AIR WAR COLLEGE AIR UNIVERSITY BOUNCING BACK FROM WAR TRAUMA: RESILIENCY IN GLOBAL WAR ON TERROR’S WOUNDED WARRIORS by Katherine H

Nursing diagnoses and interventions for post-acute-phase battered women.

PubMed

Carlson-Catalano, J

1998-01-01

To identify nursing diagnoses and interventions applicable for post-acute-phase battered women. Eight battered women were interviewed twice for 2 hours. Gordon's functional health patterns provided the framework for data collection. Fifty-three nursing diagnoses and 52 nursing interventions were indicated in the data; 24 nursing diagnoses and 26 nursing interventions were present in all participants' data. With the use of comprehensive interventions, nurses can make a major contribution to society by enabling battered women to move to a more protected lifestyle.

Phase Time and Envelope Time in Time-Distance Analysis and Acoustic Imaging

NASA Technical Reports Server (NTRS)

Chou, Dean-Yi; Duvall, Thomas L.; Sun, Ming-Tsung; Chang, Hsiang-Kuang; Jimenez, Antonio; Rabello-Soares, Maria Cristina; Ai, Guoxiang; Wang, Gwo-Ping; Goode Philip; Marquette, William;

The Post-Adolescent Phase: A By-Product and a Factor of Development.

ERIC Educational Resources Information Center

Planck, Ulrich

Conducted in 1955 and 1980, random sample interview data of 17 to 28 year-old West Germans from places of less than 5,000 inhabitants are used to support the thesis that the post-adolescent phase has been prolonged in the countryside of West Germany during these years of increasing technical and economic development. Findings indicate occupational…

Tradeoffs in Chemical and Thermal Variations in the Post-perovskite Phase Transition: Mixed Phase Regions in the Deep Lower Mantle?

NASA Astrophysics Data System (ADS)

Giles, G. F.; Spera, F. J.; Yuen, D. A.

2005-12-01

The recent discovery of a phase-transition in Mg-rich perovskite (Pv) to a post-perovskite (pPv) phase at lower mantle depths and its relationship to D", lower mantle heterogeneity and iron content prompted an investigation of the relative importance of lower mantle (LM) compositional and temperature fluctuations in creating topographic undulations on mixed phase regions. Above the transition, Mg-rich Pv makes up ~70 percent by mass of the LM. Using results from experimental phase equilibria, first-principles computations and thermodynamic relations for Fe2+-Mg mixing in silicates, a preliminary thermodynamic model for the perovskite to post-perovskite phase transition in the divariant system MgSiO3-FeSiO3 is developed. Complexities associated with components Fe2O3 and Al2O3 and other phases (Ca-Pv, magnesiowustite) are neglected. The model predicts phase transition pressures are sensitive to the FeSiO3 content of perovskite (~-1.5 GPa per one mole percent FeSiO3). This leads to considerable topography along the top boundary of the mixed phase region. The Clapeyron slope for the Pv to pPv transition at XFeSiO3=0.1 is +11 MPa/K about 20% higher than for pure Mg-Pv. Increasing bulk concentration of iron elevates the mixed (two-phase) layer above the core-mantle boundary (CMB); increasing temperature acts to push the mixed layer deeper into the LM into the D" thermal boundary layer resting upon the (CMB). For various LM geotherms and CMB temperatures, a single mixed layer of thickness ~300 km lies within the bottom 40% of the lower mantle. For low iron contents (XFeSiO3 ~5 mole percent or less), two perched layers are found. This is the divariant analog to the univariant double-crosser. The hotter the mantle, the deeper the mixed phase layer; the more iron-rich the LM, the higher the mixed phase layer. In a hotter Hadean Earth with interior temperatures everywhere 200-500 K warmer pPv is not stable unless the LM bulk composition is Fe-enriched compared to the present

Early Detection of Amyloid Plaque in Alzheimer’s Disease via X-ray Phase CT

DTIC Science & Technology

2016-08-01

AWARD NUMBER: W81XWH-12-1-0138 TITLE: Early Detection of Amyloid Plaque in Alzheimer’s Disease via X-ray Phase CT PRINCIPAL INVESTIGATOR...NUMBER W81XWH-12-1-0138 Early Detection of Amyloid Plaque in Alzheimer’s Disease via X-ray Phase CT 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...method for early detection of amyloid plaque in Alzheimer’s disease , with three Specific Aims: #1 Develop and optimize an x-ray PCCT to explore the

Physiological characteristics of wild Atlantic salmon post-smolts during estuarine and coastal migration

USGS Publications Warehouse

Stefansson, S.O.; Bjornsson, B. Th; Sundell, K.; Nyhammer, G.; McCormick, S.D.

2003-01-01

Changes were measured in some of the major physiological variables associated with seawater adaptability, growth and energetics in wild Atlantic salmon Salmo salar smolts and post-smolts migrating from the river and through the estuary, fjord and coastal areas in the River Orkla and the Trondheimsfjord, Norway during late May to early June. Gill Na+,K+-ATPase activity increased to levels of 12-16 ??mol ADP mg protein-1 h -1 in post-smolts caught in higher salinity zones, probably representing long-term levels of Atlantic salmon post-smolts in oceanic conditions. Muscle moisture was regulated within narrow limits (77.7-78.7%) in fish from all zones during both years, suggesting that post-smolts adapt to marine conditions without any long-term disturbance of hydro-mineral balance. Lipid and glycogen content showed a general trend towards depletion from the river, through the fjord and into the ocean. There was, however, no significant change in protein content. The present results confirm that smolts are naturally 'energy deficient' during downstream migration, and suggest that post-smolts also mobilize energy reserves during their early marine phase, while protein is allocated for somatic growth. Plasma growth hormone (GH) levels increased transiently during passage through the estuary and fjord, with lower levels observed in post-smolts caught off-shore, i.e. in fish which were feeding on marine prey and had adapted to the marine environment. These physiological changes may confer substantial selective advantages during the critical early marine phase of anadromous salmonids, and hence are adaptive for long-term survival in sea water. ?? 2003 The Fisheries Society of the British Isles.

Risk factors for early post-operative neurological deterioration in dogs undergoing a cervical dorsal laminectomy or hemilaminectomy: 100 cases (2002-2014).

PubMed

Taylor-Brown, F E; Cardy, T J A; Liebel, F X; Garosi, L; Kenny, P J; Volk, H A; De Decker, S

2015-12-01

Early post-operative neurological deterioration is a well-known complication following dorsal cervical laminectomies and hemilaminectomies in dogs. This study aimed to evaluate potential risk factors for early post-operative neurological deterioration following these surgical procedures. Medical records of 100 dogs that had undergone a cervical dorsal laminectomy or hemilaminectomy between 2002 and 2014 were assessed retrospectively. Assessed variables included signalment, bodyweight, duration of clinical signs, neurological status before surgery, diagnosis, surgical site, type and extent of surgery and duration of procedure. Outcome measures were neurological status immediately following surgery and duration of hospitalisation. Univariate statistical analysis was performed to identify variables to be included in a multivariate model. Diagnoses included osseous associated cervical spondylomyelopathy (OACSM; n = 41), acute intervertebral disk extrusion (IVDE; 31), meningioma (11), spinal arachnoid diverticulum (10) and vertebral arch anomalies (7). Overall 54% (95% CI 45.25-64.75) of dogs were neurologically worse 48 h post-operatively. Multivariate statistical analysis identified four factors significantly related to early post-operative neurological outcome. Diagnoses of OACSM or meningioma were considered the strongest variables to predict early post-operative neurological deterioration, followed by higher (more severely affected) neurological grade before surgery and longer surgery time. This information can aid in the management of expectations of clinical staff and owners with dogs undergoing these surgical procedures. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bouncing Back From "Deflategate"

NASA Astrophysics Data System (ADS)

DiLisi, Gregory A.; Rarick, Richard A.

2015-09-01

Halfway through the 2015 AFC Championship game between the New England Patriots and Indianapolis Colts, game officials discovered that the Patriots were using underinflated footballs on their offensive snaps. A controversy ensued because the Patriots had actually supplied these balls to the game's referee just hours before kickoff. Athletes and physicists have since agreed that using underinflated footballs gives several unfair advantages to the offensive team. Media outlets have focused their attention on two possible culprits behind the deflationary debacle: either the Patriots had intentionally underinflated their supply of footballs, or the climatic conditions, coupled with the various impacts to which the balls were subjected during the course of the game, had somehow altered the internal air pressure of the balls. This controversy soon became known as "Deflategate" (the moniker makes an obvious connection to the 1970s "Watergate" scandal). The purpose of this article is to bring Deflategate into the laboratory activities of high school and undergraduate introductory physics courses. First, we provide some background information on the actual 2015 AFC Championship game and subsequent media blitz surrounding the controversy. When used in an introductory mechanics class, this information can help students contextualize Deflategate as a real-word application of the material they are learning. Next, we recast the spotlight on Deflategate from its current focus, the ideal gas law, to a new one—namely, the physics of a bouncing ball. We then use this scenario as a motivation for a fun but informative set of experiments that can be carried out using equipment already in most high school or college laboratories. The subsequent data analysis relies on three basic principles: projectile motion, conservation of energy, and linear impulse/momentum. The analysis showcases the application of introductory physics to the world of sports, brings current events into the

Performance criteria and quality indicators for the post-analytical phase.

PubMed

Sciacovelli, Laura; Aita, Ada; Padoan, Andrea; Pelloso, Michela; Antonelli, Giorgia; Piva, Elisa; Chiozza, Maria Laura; Plebani, Mario

2016-07-01

Quality indicators (QIs) used as performance measurements are an effective tool in accurately estimating quality, identifying problems that may need to be addressed, and monitoring the processes over time. In Laboratory Medicine, QIs should cover all steps of the testing process, as error studies have confirmed that most errors occur in the pre- and post-analytical phase of testing. Aim of the present study is to provide preliminary results on QIs and related performance criteria in the post-analytical phase. This work was conducted according to a previously described study design based on the voluntary participation of clinical laboratories in the project on QIs of the Working Group "Laboratory Errors and Patient Safety" (WG-LEPS) of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). Overall, data collected highlighted an improvement or stability in performances over time for all reported indicators thus demonstrating that the use of QIs is effective in the quality improvement strategy. Moreover, QIs data are an important source for defining the state-of-the-art concerning the error rate in the total testing process. The definition of performance specifications based on the state-of-the-art, as suggested by consensus documents, is a valuable benchmark point in evaluating the performance of each laboratory. Laboratory tests play a relevant role in the monitoring and evaluation of the efficacy of patient outcome thus assisting clinicians in decision-making. Laboratory performance evaluation is therefore crucial to providing patients with safe, effective and efficient care.

Wide-field phase imaging for the endoscopic detection of dysplasia and early-stage esophageal cancer

NASA Astrophysics Data System (ADS)

Fitzpatrick, C. R. M.; Gordon, G. S. D.; Sawyer, T. W.; Wilkinson, T. D.; Bohndiek, S. E.

2018-02-01

Esophageal cancer has a 5-year survival rate below 20%, but can be curatively resected if it is detected early. At present, poor contrast for early lesions in white light imaging leads to a high miss rate in standard-of- care endoscopic surveillance. Early lesions in the esophagus, referred to as dysplasia, are characterized by an abundance of abnormal cells with enlarged nuclei. This tissue has a different refractive index profile to healthy tissue, which results in different light scattering properties and provides a source of endogenous contrast that can be exploited for advanced endoscopic imaging. For example, point measurements of such contrast can be made with scattering spectroscopy, while optical coherence tomography generates volumetric data. However, both require specialist interpretation for diagnostic decision making. We propose combining wide-field phase imaging with existing white light endoscopy in order to provide enhanced contrast for dysplasia and early-stage cancer in an image format that is familiar to endoscopists. Wide-field phase imaging in endoscopy can be achieved using coherent illumination combined with phase retrieval algorithms. Here, we present the design and simulation of a benchtop phase imaging system that is compatible with capsule endoscopy. We have undertaken preliminary optical modelling of the phase imaging setup, including aberration correction simulations and an investigation into distinguishing between different tissue phantom scattering coefficients. As our approach is based on phase retrieval rather than interferometry, it is feasible to realize a device with low-cost components for future clinical implementation.

W.A. Parish Post-Combustion CO{sub 2} Capture and Sequestration Project Phase 1 Definition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armpriester, Anthony; Smith, Roger; Scheriffius, Jeff

2014-02-01

For a secure and sustainable energy future, the United States (U.S.) must reduce its dependence on imported oil and reduce its emissions of carbon dioxide (CO{sub 2}) and other greenhouse gases (GHGs). To meet these strategic challenges, the U.S. wiU have to create fundamentally new technologies with performance levels far beyond what is now possible. Developing advanced post-combustion clean coal technologies for capturing CO{sub 2} from existing coal-fired power plants can play a major role in the country's transition to a sustainable energy future, especially when coupled with CO{sub 2}-enhanced oil recovery (CO{sub 2}-EOR). Pursuant to these goals, NRG Energy,more » Inc. (NRG) submitted an application and entered into a cost-shared collaboration with the U.S. Department of Energy (DOE) under Round 3 of the Clean Coal Power Initiative (CCPI) to advance low-emission coal technologies. The objective of the NRG W A Parish Post-Combustion CO{sub 2} Capture and Sequestration Demonstration Project is to establish the technical feasibility and economic viability of post-combustion CO{sub 2} capture using flue gas from an existing pulverized coal-fired boiler integrated with geologic sequestration via an enhanced oil recovery (EOR) process. To achieve these objectives, the project will be executed in three phases. Each phase represents a distinct aspect of the project execution. The project phases are: • Phase I. Project Definition/Front-End Engineering Design (FEED) • Phase ll. Detailed Engineering, Procurement & Construction • Phase III. Demonstration and Monitoring The purpose of Phase I is to develop the project in sufficient detail to facilitate the decision-making process in progressing to the next stage of project delivery. Phase n. This report provides a complete summary of the FEED study effort, including pertinent project background information, the scope of facilities covered, decisions, challenges, and considerations made regarding configuration and

Implementing the Bounce Back trauma intervention in urban elementary schools: A real-world replication trial.

PubMed

Santiago, Catherine DeCarlo; Raviv, Tali; Ros, Anna Maria; Brewer, Stephanie K; Distel, Laura M L; Torres, Stephanie A; Fuller, Anne K; Lewis, Krystal M; Coyne, Claire A; Cicchetti, Colleen; Langley, Audra K

2018-03-01

The current study provides the first replication trial of Bounce Back, a school-based intervention for elementary students exposed to trauma, in a different school district and geographical area. Participants in this study were 52 1st through 4th graders (Mage = 7.76 years; 65% male) who were predominately Latino (82%). Schools were randomly assigned to immediate treatment or waitlist control. Differential treatment effects (Time × Group Interaction) were found for child-reported posttraumatic stress disorder (PTSD) and parent-reported child coping, indicating that the immediate treatment group showed greater reductions in PTSD and improvements in coping compared with the delayed group. Differential treatment effects were not significant for depression or anxiety. Significant maintenance effects were found for both child-reported PTSD and depression as well as parent-reported PTSD and coping for the immediate treatment group at follow-up. Significant treatment effects were also found in the delayed treatment group, showing reductions in child-reported PTSD, depression, and anxiety as well as parent-reported depression and coping upon receiving treatment. In conclusion, the current study suggests that Bounce Back is an effective intervention for reducing PTSD symptoms and improving coping skills, even among a sample experiencing high levels of trauma and other ongoing stressors. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Elongator promotes germination and early post-germination growth.

PubMed

Woloszynska, Magdalena; Gagliardi, Olimpia; Vandenbussche, Filip; Van Lijsebettens, Mieke

2018-01-02

The Elongator complex interacts with RNA polymerase II and via histone acetylation and DNA demethylation facilitates epigenetically the transcription of genes involved in diverse processes in plants, including growth, development, and immune response. Recently, we have shown that the Elongator complex promotes hypocotyl elongation and photomorphogenesis in Arabidopsis thaliana by regulating the photomorphogenesis and growth-related gene network that converges on genes implicated in cell wall biogenesis and hormone signaling. Here, we report that germination in the elo mutant was delayed by 6 h in the dark when compared to the wild type in a time lapse and germination assay. A number of germination-correlated genes were down-regulated in the elo transcriptome, suggesting a transcriptional regulation by Elongator. We also show that the hypocotyl elongation defect observed in the elo mutants in darkness originates very early in the post-germination development and is independent from the germination delay.

Accumulation of unsaturated lipids in monocytes during early phase pyrogen tolerance.

PubMed

Szewczenko-Pawlikowski, M; Kozak, W

2000-04-12

This paper presents data that inspired a new explanation for the mechanism of early phase endotoxin tolerance. Rabbits injected intravenously with LPS from Salmonella abortus developed a two-phase fever (6 h) and monophasic hyperlipidemia of very low density lipoproteins (two consecutive days). If during these days rabbits were injected with the same dose of LPS at 24-h intervals, the second phase of fever disappeared, i.e. early phase pyrogenic tolerance was obtained. This was correlated with a decrease of lipoprotein hyperlipidemia (measured 1.5 h after LPS injection) and an accumulation of lipids rich in double bonds in monocytes (measured 3.5 h after LPS injection). Results showed that the degree of unsaturation of acyl chains (AC) in monocytes (AC/DB, DB=double bonds) is negatively correlated (r=-0.72) with fever response (fever index). The authors maintain that a gradual increase in monocyte membrane fluidity is an adaptation to repeated exposure of monocytes to lipid A and is responsible for the progressive desensitization of monocytes to endotoxin. It is suggested that disorders of this mechanism lead to an accumulation of abnormal quantities of saturated lipids and cholesterol within macrophages, which, as foam cells, are the starting point for atherosclerosis pathology.

Post-early cretaceous landform evolution along the western margin of the banca~nnia trough, western nsw

USGS Publications Warehouse

Gibson, D.L.

2000-01-01

Previously undated post-Devonian sediments outcropping north of Fowlers Gap station near the western margin of the Bancannia Trough are shown by plant macro- and microfossil determinations to be of Early Cretaceous (most likely Neocomian and/or Aptian) age, and thus part of the Eromanga Basin. They are assigned to the previously defined Telephone Creek Formation. Study of the structural configuration of this unit and the unconformably underlying Devonian rocks suggests that the gross landscape architecture of the area results from post-Early Cretaceous monoclinal folding along blind faults at the western margin of the trough, combined with the effects of differential erosion. This study shows that, while landscape evolution in the area has been dynamic, the major changes that have occurred are on a geological rather than human timescale.

Phase III Early Restoration Meeting - Port Arthur, TX | NOAA Gulf Spill

Science.gov Websites

Areas Alabama Florida Louisiana Mississippi Texas Region-wide Open Ocean Data Media & News planning for Phase III and future early restoration plans. Open House: 6:00pm Public Meeting: 6:30pm

Phase III Early Restoration Meeting - Panama City, FL | NOAA Gulf Spill

Science.gov Websites

Areas Alabama Florida Louisiana Mississippi Texas Region-wide Open Ocean Data Media & News planning for Phase III and future early restoration plans. Open House: 6:00pm Public Meeting: 6:30pm

Beryllium and boron constraints on an early Galactic bright phase

NASA Technical Reports Server (NTRS)

Fields, Brian D.; Schramm, David N.; Truran, James W.

1993-01-01

The recent observations of Be and B in metal-deficient halo dwarfs are used to constrain a 'bright phase' of enhanced cosmic-ray flux in the early Galaxy. Assuming that this Be and B arises from cosmic-ray spallation in the early Galaxy, limits are placed on the intensity of the early (Population II) cosmic-ray flux relative to the present (Population I) flux. A simple estimate of bounds on the flux ratio is 1 - 40. This upper bound would restrict galaxies like our own from producing neutrino fluxes that would be detectable in any currently proposed detectors. It is found that the relative enhancement of the early flux varies inversely with the relative time of enhancement. It is noted that associated gamma-ray production via pp - pi sup 0 pp may be a significant contribution to the gamma-ray background above 100 MeV.

CD26: A Prognostic Marker of Acute Lymphoblastic Leukemia in Children in the Post Remission Induction Phase.

PubMed

Mehde, Atheer Awad; Yusof, Faridah; Adel Mehdi, Wesen; Zainulabdeen, Jwan Abdulmohsin

2015-01-01

ALL is an irredeemable disease due to the resistance to treatment. There are several influences which are involved in such resistance to chemotherapy, including oxidative stress as a result of the generation of reactive oxygen species (ROS) and presence of hypodiploid cells. Cluster of differentiation 26 (CD26), also known as dipeptidyl peptidase-4, is a 110 kDa, multifunctional, membrane-bound glycoprotein. The aim of this study was to evaluate the clinical significance of serum CD26 in patients with acute lymphoblastic leukaemia patients in the post remission induction phase, as well as the relationship between CD26 activity and the oxidative stress status. CD26, total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI), in addition to activity of related enzymes myeloperoxidase, glutathione- s-transferase and xanthine oxidase, were analysed in sixty children with acute lymphoblastic leukaemia in the post remission induction phase. The study showed significant elevation in CD26, TOS and OSI levels in patients with acute lymphoblastic leukaemia in the post remission induction phase in comparison to healthy control samples. In contrast, myeloperoxidase, glutathione-s-transferase and xanthine oxidase activities were decreased significantly. A significant correlation between CD26 concentration and some oxidative stress parameters was evident in ALL patients. Serum levels of CD26 appear to be useful as a new biomarker of oxidative stress in children with acute lymphoblastic leukaemia in the post remission induction phase, and levels of antioxidants must be regularly estimated during the treatment of children with ALL.

Instability of the layered orthorhombic post-perovskite phase of SrTiO3 and other candidate orthorhombic phases under pressure

NASA Astrophysics Data System (ADS)

Bhandari, Churna; Lambrecht, Walter R. L.

2018-06-01

While the tetragonal antiferro-electrically distorted (AFD) phase with space group I 4 / mcm is well known for SrTiO3 to occur below 105 K, there are also some hints in the literature of an orthorhombic phase, either at the lower temperature or at high pressure. A previously proposed orthorhombic layered structure of SrTiO3, known as the post-perovskite or CaIrO3 structure with space group Cmcm is shown to have significantly higher energy than the cubic or tetragonal phase and to have its minimum volume at larger volume than cubic perovskite. The Cmcm structure is thus ruled out. We also study an alternative Pnma phase obtained by two octahedral rotations about different axes. This phase is found to have slightly lower energy than the I 4 / mcm phase in spite of the fact that its parent, in-phase tilted P 4 / mbm phase is not found to occur. Our calculated enthalpies of formation show that the I 4 / mcm phase occurs at slightly higher volume than the cubic phase and has a negative transition pressure relative to the cubic phase, which suggests that it does not correspond to the high-pressure tetragonal phase. The enthalpy of the Pnma phase is almost indistinguishable from the I 4 / mcm phase. Alternative ferro-electric tetragonal and orthorhombic structures previously suggested in literature are discussed.

Early Childhood Technology Integrated Instructional System (EC-TIIS) Phase 1: A Final Report

ERIC Educational Resources Information Center

Hutinger, Patricia; Robinson, Linda; Schneider, Carol

2004-01-01

The Early Childhood Technology Integrated Instructional System (EC-TIIS), a Steppingstones of Technology Innovation Phase 1--Development project, was developed by the Center for Best Practices in Early Childhood (the Center) at Western Illinois University as an online instructional system. EC-TIIS' ultimate goal was to improve technology services…

Early diagnosis of post-varicella necrotising fasciitis: A medical and surgical emergency

PubMed Central

Xavier, Rose; Abraham, Bobby; Cherian, Vinod Jacob; Joseph, Jobin I.

2016-01-01

Necrotising fasciitis (NF) is an extremely rare complication of a rather common paediatric viral exanthem varicella. Delayed diagnosis and treatment can lead to significant morbidity and mortality. Laboratory risk indicator of NF score aids in early clinical diagnosis in suspected cases of post-varicella NF thus enabling timely intervention. Surgery delayed for more than 24 hours, is an independent risk factor for death. Surgical debridement with good antibiotic coverage is the definitive treatment for NF. PMID:27251524

Dispositional Optimism and Therapeutic Expectations in Early Phase Oncology Trials

PubMed Central

Jansen, Lynn A.; Mahadevan, Daruka; Appelbaum, Paul S.; Klein, William MP; Weinstein, Neil D.; Mori, Motomi; Daffé, Racky; Sulmasy, Daniel P.

2016-01-01

Purpose Prior research has identified unrealistic optimism as a bias that might impair informed consent among patient-subjects in early phase oncology trials. Optimism, however, is not a unitary construct – it can also be defined as a general disposition, or what is called dispositional optimism. We assessed whether dispositional optimism would be related to high expectations for personal therapeutic benefit reported by patient-subjects in these trials but not to the therapeutic misconception. We also assessed how dispositional optimism related to unrealistic optimism. Methods Patient-subjects completed questionnaires designed to measure expectations for therapeutic benefit, dispositional optimism, unrealistic optimism, and the therapeutic misconception. Results Dispositional optimism was significantly associated with higher expectations for personal therapeutic benefit (Spearman r=0.333, p<0.0001), but was not associated with the therapeutic misconception. (Spearman r=−0.075, p=0.329). Dispositional optimism was weakly associated with unrealistic optimism (Spearman r=0.215, p=0.005). In multivariate analysis, both dispositional optimism (p=0.02) and unrealistic optimism (p<0.0001) were independently associated with high expectations for personal therapeutic benefit. Unrealistic optimism (p=.0001), but not dispositional optimism, was independently associated with the therapeutic misconception. Conclusion High expectations for therapeutic benefit among patient-subjects in early phase oncology trials should not be assumed to result from misunderstanding of specific information about the trials. Our data reveal that these expectations are associated with either a dispositionally positive outlook on life or biased expectations about specific aspects of trial participation. Not all manifestations of optimism are the same, and different types of optimism likely have different consequences for informed consent in early phase oncology research. PMID:26882017

Translocation and early post-release demography of endangered Laysan teal

USGS Publications Warehouse

Reynolds, M.H.; Seavy, N.E.; Vekasy, M.S.; Klavitter, J.L.; Laniawe, L.P.

2008-01-01

In an attempt to reduce the high extinction risk inherent to small island populations, we translocated wild Laysan teal Anas laysanensis to a portion of its presumed prehistoric range. Most avian translocations lack the strategic post-release monitoring needed to assess early population establishment or failure. Therefore, we monitored the survival and reproduction of all founders, and their first-generation offspring using radio telemetry for 2 years after the first release. Forty-two Laysan teal were sourced directly from the only extant population on Laysan Island and transported 2 days by ship to Midway Atoll. All birds survived the translocation with nutritional and veterinary support, and spent between 4 and 14 days in captivity. Post-release survival of 42 founders was 0.857 (95% CI 0.86-0.99) during 2004-2006 or annualized 0.92 (95% CI 0.83-0.98). Seventeen of 18 founding hens attempted nesting in the first two breeding seasons. Fledgling success was 0.57 (95% CI 0.55-0.60) in 2005 and 0.63 (95% CI 0.62-0.64) in 2006. The effective founding female population (Ne) was 13. We applied these initial demographic rates to model population growth. The nascent population size increased to >100 after only 2 years post-release (?? = 1.73). If this growth rate continues, the size of the Midway population could surpass the source population before 2010. ?? 2008 The Authors. Journal compilation ?? 2008 The Zoological Society of London.

Palaeoredox indicators from the organic-rich Messinian early post-evaporitic deposits of the Apennines (Central Italy)

NASA Astrophysics Data System (ADS)

Sampalmieri, G.; Iadanza, A.; Cipollari, P.; Cosentino, D.; Lo Mastro, S.

2009-04-01

Bottom redox conditions in marine and lacustrine ancient basins are often inferred by the occurrence of peculiar sedimentological structures and microfaunal assemblages. The co-occurrence, in such environments, of authigenic uranium, framboidal pyrite, barite and Fe-Mn nodules and encrustations, provides a good constraint for palaeo reconstructions. Authigenic uranium is a common constituent of hydrocarbon source rocks: it forms at the sediment-water interface under oxygen-deficient conditions and accumulates together with organic matter (OM). Its precipitation is triggered by the reduction of the soluble U6+ion in seawater to insoluble U4+. With respect to black shales, uranium content has even been used to estimate the TOC. Also authigenic pyrite forms under anoxic conditions and replaces organic matter: 1) the increase in pyrite content and in organic matter are directly correlated; 2) the size distribution of framboidal pyrite (consistent with sulphate-reducing bacterial activity) is considered a measure of redox conditions within the sediment. Barite is an authigenic mineral related to Corg content, since its organic precipitation is triggered by sulphate-reduction processes occurring in decaying OM-bearing microenvironments. Finally, also Fe-Mn oxyhydroxide are typical indicators of redox conditions. About 6 My ago the Mediterranean Sea underwent a giant event of concentration referred to as Messinian Salinity Crisis, which can be roughly subdivided into an evaporitic and a post evaporitic phase. The post evaporitic phase (p-ev; 5.61-5.33 Ma) developed in a context of humid conditions and can be further distinguished into two steps: p-ev1 (early post evaporitic phase) and p-ev2 (late post evaporitic phase). Previous works focused on pev2, which is interpreted to represent the establishment of brackish water conditions (Lago-Mare biofacies). In other respects, the palaeoenvironment of p-ev1 deposits, mostly represented by resedimented evaporitic deposits or

Impact of pretransplant rifaximin therapy on early post-liver transplant infections.

PubMed

Esfeh, Jamak Modaresi; Hanouneh, Ibrahim A; Koval, Christine E; Kovacs, Christopher; Dalal, Deepan S; Ansari-Gilani, Kianoush; Confer, Bradley D; Eghtesad, Bijan; Zein, Nizar N; Menon, K V Narayanan

2014-05-01

Bacterial and fungal infections are major causes of morbidity and mortality after liver transplantation (LT). The role of intestinal decontamination in the prevention of post-LT infections is controversial. Rifaximin is widely used for the treatment of hepatic encephalopathy. The effect of rifaximin on post-LT infections is unknown. The aim of our study was to determine the effect of rifaximin therapy in the pretransplant period on early bacterial infections (EBIs) and fungal infections within the first 30 days after LT. All adult patients who underwent LT at our institution (January 2009 to July 2011) were included in this retrospective cohort study. Patients receiving antibiotics other than pretransplant protocol antibiotics were excluded. Patients were stratified into 2 groups based on the presence or absence of rifaximin therapy for at least 2 days before LT. Infections were defined by the isolation of any bacterial or fungal organisms within 30 days of LT. Multivariate regression analysis, Student t tests, and Pearson's chi-square tests were used to compare the 2 groups. Two hundred sixty-eight patients were included, and 71 of these patients (26.5%) were on rifaximin at the time of LT. The 2 groups were comparable with respect to age, sex, race, and Model for End-Stage Liver Disease score. There were no significant differences in the rates of EBIs (30% for the non-rifaximin group and 25% for the rifaximin group, P = 0.48) or fungal infections between the 2 groups. There was no increase in antimicrobial resistance among the infecting organisms. There was no difference in survival between the rifaximin and non-rifaximin groups (98% versus 97%, P = 0.36). In conclusion, the use of rifaximin in the pre-LT period was not associated with an increased risk of bacterial or fungal infections in the early post-LT period. © 2014 American Association for the Study of Liver Diseases.

Early prediction of oral calcium and vitamin D requirements in post-thyroidectomy hypocalcaemia.

PubMed

Al-Dhahri, Saleh F; Mubasher, Mohamed; Al-Muhawas, Fida; Alessa, Mohammed; Terkawi, Rayan S; Terkawi, Abdullah S

2014-09-01

To optimize and individualize post-thyroidectomy hypocalcemia management. A multicenter prospective cohort study. Two tertiary care hospitals. parathyroid hormone (PTH) was measured preoperatively, then at 1 and 6 hours after surgery. The required doses of calcium and vitamin D were defined as those maintaining the patients asymptomatic and their cCa ≥ 2 mmol/L. They were used as an endpoint in a generalized linear mixed effect model (GLIMMEX) aiming to identify the best predictors of these optimal required doses. Models were evaluated by goodness of fit and Receiver Operating Characteristic (ROC) curves. One hundred and sixty-eight patients were analyzed; 85.1% were female, 49.3% had BMI > 30, and 64% had vitamin D deficiency. Post-thyroidectomy hypocalcemia was found in 25.6%, of whom 18 (41.9%) were symptomatic and received intravenous calcium. First hour percentage of drop in PTH correlated positively with the severity of hypocalcemia (P < .0001). The GLIMMIX prediction model for oral calcium requirement was based on first-hour percentage change from preoperative PTH level, preoperative actual PTH, BMI, and thyroid function. The same predictors were identified for vitamin D, except that thyroid function was replaced with vitamin D status. These factors were used to build predictive equations for calcium and vitamin D doses. Our findings help to optimize management of post-thyroidectomy hypocalcemia by assisting in the early identification of those who are not at risk of hypocalcaemia and by guiding early effective management of those at risk. This may reduce complications and medical cost. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

78 FR 39736 - Draft Guidance for Industry: Considerations for the Design of Early-Phase Clinical Trials of...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-02

..., choosing a study population, using a control group and blinding, dose selection, treatment plans...] Draft Guidance for Industry: Considerations for the Design of Early-Phase Clinical Trials of Cellular... document entitled ``Guidance for Industry: Considerations for the Design of Early-Phase Clinical Trials of...

A boost and bounce theory of temporal attention.

PubMed

Olivers, Christian N L; Meeter, Martijn

2008-10-01

What is the time course of visual attention? Attentional blink studies have found that the 2nd of 2 targets is often missed when presented within about 500 ms from the 1st target, resulting in theories about relatively long-lasting capacity limitations or bottlenecks. Earlier studies, however, reported quite the opposite finding: Attention is transiently enhanced, rather than reduced, for several hundreds of milliseconds after a relevant event. The authors present a general theory, as well as a working computational model, that integrate these findings. There is no central role for capacity limitations or bottlenecks. Central is a rapidly responding gating system (or attentional filter) that seeks to enhance relevant and suppress irrelevant information. When items sufficiently match the target description, they elicit transient excitatory feedback activity (a "boost" function), meant to provide access to working memory. However, in the attentional blink task, the distractor after the target is accidentally boosted, resulting in subsequent strong inhibitory feedback response (a "bounce"), which, in effect, closes the gate to working memory. The theory explains many findings that are problematic for limited-capacity accounts, including a new experiment showing that the attentional blink can be postponed.

The gga-let-7 family post-transcriptionally regulates TGFBR1 and LIN28B during the differentiation process in early chick development.

PubMed

Lee, Sang In; Jeon, Mi-Hyang; Kim, Jeom Sun; Jeon, Ik-Soo; Byun, Sung June

2015-12-01

Early chick embryogenesis is governed by a complex mechanism involving transcriptional and post-transcriptional regulation, although how post-transcriptional processes influence the balance between pluripotency and differentiation during early chick development have not been previously investigated. Here, we characterized the microRNA (miRNA) signature associated with differentiation in the chick embryo, and found that as expression of the gga-let-7 family increases through early development, expression of their direct targets, TGFBR1 and LIN28B, decreases; indeed, gga-let-7a-5p and gga-let-7b miRNAs directly bind to TGFBR1 and LIN28B transcripts. Our data further indicate that TGFBR1 and LIN28B maintain pluripotency by regulating POUV, NANOG, and CRIPTO. Therefore, gga-let-7 miRNAs act as post-transcriptional regulators of differentiation in blastodermal cells by repressing the expression of the TGFBR1 and LIN28B, which intrinsically controls blastodermal cell differentiation in early chick development. © 2015 Wiley Periodicals, Inc.

Howling at the moon? The effect of lunar phases on post-surgical pain outcome.

PubMed

Komann, Marcus; Weinmann, Claudia; Meissner, Winfried

2014-05-01

Many people are convinced that lunar phases influence their lives - despite the fact that a lot of studies have shown that this belief is wrong. In this article, we investigate the effect of lunar phases on acute post-surgical pain and on treatment-related side effects. We hypothesize that there is no influence. The data for the study were collected in 2010 and 2011 in 10 international hospitals participating in the research project PAIN OUT. Hospitalized patients were asked for their pain after surgery and pain treatment side effects using numerical ratings scales from 0 to 10. We applied Kurskal-Wallis H-tests to find out if the four moon phases show significant differences in 14 outcome variables. Afterwards, we adjusted for age, gender and three tracer surgeries. A total of 12,224 patient data sets were assessed. For most variables and sub-groups, there is no lunar effect on the observed outcome variables. The only items that show statistically significant differences are pain interference with sleep (p = 0.01) and drowsiness (p = 0.01). The only sub-groups that show statistically significant connections to lunar phases in some variables are men (7 out of 14 variables significant) and elderly people (4 out of 14 variables significant). Even in the statistically significant sub-groups, the differences are small and only show up in some variables. We conclude that lunar phases have no effect on post-surgical pain or its side effects. The hypothesis holds. Thus, there is no reason for patients to postpone surgeries or to fear surgeries on any given date.

Identification of ICF categories relevant for nursing in the situation of acute and early post-acute rehabilitation

PubMed Central

Mueller, Martin; Boldt, Christine; Grill, Eva; Strobl, Ralf; Stucki, Gerold

2008-01-01

Background The recovery of patients after an acute episode of illness or injury depends both on adequate medical treatment and on the early identification of needs for rehabilitation care. The process of early beginning rehabilitation requires efficient communication both between health professionals and the patient in order to effectively address all rehabilitation goals. The currently used nursing taxonomies, however, are not intended for interdisciplinary use and thus may not contribute to efficient rehabilitation management and an optimal patient outcome. The ICF might be the missing link in this communication process. The objective of this study was to identify the categories of the International Classification of Functioning, Disability and Health (ICF) categories relevant for nursing care in the situation of acute and early post-acute rehabilitation. Methods First, in a consensus process, "Leistungserfassung in der Pflege" (LEP) nursing interventions relevant for the situation of acute and early post-acute rehabilitation were selected. Second, in an integrated two-step linking process, two nursing experts derived goals of LEP nursing interventions from their practical knowledge and selected corresponding ICF categories most relevant for patients in acute and post-acute rehabilitation (ICF Core Sets). Results Eighty-seven percent of ICF Core Set categories could be linked to goals of at least one nursing intervention variable of LEP. The ICF categories most frequently linked with LEP nursing interventions were respiration functions, experience of self and time functions and focusing attention. Thirteen percent of ICF Core Set categories could not be linked with LEP nursing interventions. The LEP nursing interventions which were linked with the highest number of different ICF-categories of all were "therapeutic intervention", "patient-nurse communication/information giving" and "mobilising". Conclusion The ICF Core Sets for the acute hospital and early post

Collaborative Leadership Practices among Ohio's Early College High School Principals and Their Post-Secondary Partners

ERIC Educational Resources Information Center

Carter, Allia L.

2012-01-01

This constructivist multiple-case study examined the collaborative leadership practices of seven secondary and seven post-secondary leaders who participate in Ohio's Early College High School Initiative (ECHSI). The 14 educational leaders in this study partnered in an effort to respond to the access and success of traditionally underrepresented…

Webcam delivery of the Lidcombe program for early stuttering: a phase I clinical trial.

PubMed

O'Brian, Sue; Smith, Kylie; Onslow, Mark

2014-06-01

The Lidcombe Program is an operant treatment for early stuttering shown with meta-analysis to have a favorable odds ratio. However, many clients are unable to access the treatment because of distance and lifestyle factors. In this Phase I trial, we explored the potential efficacy, practicality, and viability of an Internet webcam Lidcombe Program service delivery model. Participants were 3 preschool children who stuttered and their parents, all of whom received assessment and treatment using webcam in their homes with no clinic attendance. At 6 months post-Stage 1 completion, all children were stuttering below 1.0% syllables stuttered. The webcam intervention was acceptable to the parents and appeared to be practical and viable, with only occasional audiovisual problems. At present, there is no reason to doubt that a webcam-delivered Lidcombe Program will be shown with clinical trials to have comparable efficacy with the clinic version. Webcam-delivered Lidcombe Program intervention is potentially efficacious, is practical and viable, and requires further exploration with comparative clinical trials and a qualitative study of parent and caregiver experiences.

Exploring the impact of visual and movement based priming on a motor intervention in the acute phase post-stroke in persons with severe hemiparesis of the upper extremity.

PubMed

Patel, Jigna; Qiu, Qinyin; Yarossi, Mathew; Merians, Alma; Massood, Supriya; Tunik, Eugene; Adamovich, Sergei; Fluet, Gerard

2017-07-01

Explore the potential benefits of using priming methods prior to an active hand task in the acute phase post-stroke in persons with severe upper extremity hemiparesis. Five individuals were trained using priming techniques including virtual reality (VR) based visual mirror feedback and contralaterally controlled passive movement strategies prior to training with an active pinch force modulation task. Clinical, kinetic, and neurophysiological measurements were taken pre and post the training period. Clinical measures were taken at six months post training. The two priming simulations and active training were well tolerated early after stroke. Priming effects were suggested by increased maximal pinch force immediately after visual and movement based priming. Despite having no clinically observable movement distally, the subjects were able to volitionally coordinate isometric force and muscle activity (EMG) in a pinch tracing task. The Root Mean Square Error (RMSE) of force during the pinch trace task gradually decreased over the training period suggesting learning may have occurred. Changes in motor cortical neurophysiology were seen in the unaffected hemisphere using Transcranial Magnetic Stimulation (TMS) mapping. Significant improvements in motor recovery as measured by the Action Research Arm Test (ARAT) and the Upper Extremity Fugl Meyer Assessment (UEFMA) were demonstrated at six months post training by three of the five subjects. This study suggests that an early hand-based intervention using visual and movement based priming activities and a scaled motor task allows participation by persons without the motor control required for traditionally presented rehabilitation and testing. Implications for Rehabilitation Rehabilitation of individuals with severely paretic upper extremities after stroke is challenging due to limited movement capacity and few options for therapeutic training. Long-term functional recovery of the arm after stroke depends on early return

Temporal deformation pattern in acute and late phases of ST-elevation myocardial infarction: incremental value of longitudinal post-systolic strain to assess myocardial viability.

PubMed

Huttin, Olivier; Marie, Pierre-Yves; Benichou, Maxime; Bozec, Erwan; Lemoine, Simon; Mandry, Damien; Juillière, Yves; Sadoul, Nicolas; Micard, Emilien; Duarte, Kevin; Beaumont, Marine; Rossignol, Patrick; Girerd, Nicolas; Selton-Suty, Christine

2016-10-01

Identification of transmural extent and degree of non-viability after ST-segment elevation myocardial infarction (STEMI) is clinically important. The objective of the present study was to assess the regional mechanics and temporal deformation patterns using speckle tracking echocardiography (STE) in acute and later phases of STEMI to predict myocardial damage in these patients. Ninety-eight patients with first STEMI underwent both echocardiography and cardiac magnetic resonance imaging in acute phase and at 6 months follow-up with 2D STE-derived measurements of peak longitudinal strain (PLS), Pre-STretch index (PST) and post-systolic deformation index (PSI). For each segment, late gadolinium enhancement (LGE) was defined as transmural (LGE >66 %) or non-transmural (<66 %). Global deformation values were significantly correlated with LVEFCMR and infarct size at both visits. A significantly lower value of segmental PLS and higher PSI and PST in necrotic segments were observed comparatively to control, adjacent and remote segments. The best parameters to predict transmural extent in acute phase were PSI with a cutoff value of 8 % (AUC: 0.84) and PLS with a cutoff value of -13 % (AUC: 0.86). PST showed high specificity, but poor sensitivity in predicting transmural extent. More importantly, the addition of PSI and PST to PLS in acute phase was associated with improved prediction of viability at 6 months (integrated discrimination improvement 2.5 % p < 0.01; net reclassification improvement 27 %; p < 0.01). All systolic deformation values separated transmural from non-transmural scarring. PLS combined with additional information relative to post-systolic deformation appears to be the most informative parameters to predict the transmural extent of MI in the early and late phases of MI. http://clinicaltrials.gov/show/NCT01109225 ; NCT01109225.

Numerical investigation of the early flight phase in ski-jumping.

PubMed

Gardan, N; Schneider, A; Polidori, G; Trenchard, H; Seigneur, J M; Beaumont, F; Fourchet, F; Taiar, R

2017-07-05

The purpose of this study is to develop a numerical methodology based on real data from wind tunnel experiments to investigate the effect of the ski jumper's posture and speed on aerodynamic forces in a wide range of angles of attack. To improve our knowledge of the aerodynamic behavior of the ski jumper and his equipment during the early flight phase of the ski jump, we applied CFD methodology to evaluate the influence of angle of attack (α=14°, 21.5°, 29°, 36.5° and 44°) and speed (u=23, 26 and 29m/s) on aerodynamic forces in the situation of stable attitude of the ski jumper's body and skis. The standard k-ω turbulence model was used to investigate both the influence of the ski jumper's posture and speed on aerodynamic performance during the early flight phase. Numerical results show that the ski jumper's speed has very little impact on the lift and drag coefficients. Conversely, the lift and drag forces acting on the ski jumper's body during the early flight phase of the jump are strongly influenced by the variations of the angle of attack. The present results suggest that the greater the ski jumper's angle of inclination, with respect to the relative flow, the greater the pressure difference between the lower and upper parts of the skier. Further studies will focus on the dependency of the parameters with both the angle of attack α and the body-ski angle β as control variables. It will be possible to test and optimize different ski jumping styles in different ski jumping hills and investigate different environmental conditions such as temperature, altitude or crosswinds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dispositional optimism and therapeutic expectations in early-phase oncology trials.

PubMed

Jansen, Lynn A; Mahadevan, Daruka; Appelbaum, Paul S; Klein, William M P; Weinstein, Neil D; Mori, Motomi; Daffé, Racky; Sulmasy, Daniel P

2016-04-15

Prior research has identified unrealistic optimism as a bias that might impair informed consent among patient-subjects in early-phase oncology trials. However, optimism is not a unitary construct; it also can be defined as a general disposition, or what is called dispositional optimism. The authors assessed whether dispositional optimism would be related to high expectations for personal therapeutic benefit reported by patient-subjects in these trials but not to the therapeutic misconception. The authors also assessed how dispositional optimism related to unrealistic optimism. Patient-subjects completed questionnaires designed to measure expectations for therapeutic benefit, dispositional optimism, unrealistic optimism, and the therapeutic misconception. Dispositional optimism was found to be significantly associated with higher expectations for personal therapeutic benefit (Spearman rank correlation coefficient [r], 0.333; P<.0001), but was not associated with the therapeutic misconception (Spearman r, -0.075; P = .329). Dispositional optimism was found to be weakly associated with unrealistic optimism (Spearman r, 0.215; P = .005). On multivariate analysis, both dispositional optimism (P = .02) and unrealistic optimism (P<.0001) were found to be independently associated with high expectations for personal therapeutic benefit. Unrealistic optimism (P = .0001), but not dispositional optimism, was found to be independently associated with the therapeutic misconception. High expectations for therapeutic benefit among patient-subjects in early-phase oncology trials should not be assumed to result from misunderstanding of specific information regarding the trials. The data from the current study indicate that these expectations are associated with either a dispositionally positive outlook on life or biased expectations concerning specific aspects of trial participation. Not all manifestations of optimism are the same, and different types of optimism likely have

Role of Occult and Post-acute Phase Replication in Protective Immunity Induced with a Novel Live Attenuated SIV Vaccine

PubMed Central

Ham, Claire; Ferguson, Deborah; Tudor, Hannah; Mattiuzzo, Giada; Klaver, Bep; Page, Mark; Stebbings, Richard; Das, Atze T.; Berkhout, Ben; Almond, Neil; Cranage, Martin P.

2016-01-01

In order to evaluate the role of persisting virus replication during occult phase immunisation in the live attenuated SIV vaccine model, a novel SIVmac239Δnef variant (SIVrtTA) genetically engineered to replicate in the presence of doxycycline was evaluated for its ability to protect against wild-type SIVmac239. Indian rhesus macaques were vaccinated either with SIVrtTA or with SIVmac239Δnef. Doxycycline was withdrawn from 4 of 8 SIVrtTA vaccinates before challenge with wild-type virus. Unvaccinated challenge controls exhibited ~107 peak plasma viral RNA copies/ml persisting beyond the acute phase. Six vaccinates, four SIVmac239Δnef and two SIVrtTA vaccinates exhibited complete protection, defined by lack of wild-type viraemia post-challenge and virus-specific PCR analysis of tissues recovered post-mortem, whereas six SIVrtTA vaccinates were protected from high levels of viraemia. Critically, the complete protection in two SIVrtTA vaccinates was associated with enhanced SIVrtTA replication in the immediate post-acute vaccination period but was independent of doxycycline status at the time of challenge. Mutations were identified in the LTR promoter region and rtTA gene that do not affect doxycycline-control but were associated with enhanced post-acute phase replication in protected vaccinates. High frequencies of total circulating CD8+T effector memory cells and a higher total frequency of SIV-specific CD8+ mono and polyfunctional T cells on the day of wild-type challenge were associated with complete protection but these parameters were not predictive of outcome when assessed 130 days after challenge. Moreover, challenge virus-specific Nef CD8+ polyfunctional T cell responses and antigen were detected in tissues post mortem in completely-protected macaques indicating post-challenge control of infection. Within the parameters of the study design, on-going occult-phase replication may not be absolutely required for protective immunity. PMID:28002473

Predictivity of Early Depressive Symptoms for Post-Stroke Depression.

PubMed

Lewin-Richter, A; Volz, M; Jöbges, M; Werheid, K

2015-08-01

Depression is a frequent complication after stroke. However, little is known about the predictive value of early self-reported depressive symptoms (DS) for later development of post-stroke depression (PSD) 6 months after discharge. Using a prospective longitudinal design, we investigated the prevalence of DS and examined their predictive value for depressive disorders 6 months after stroke while statistically controlling major established PSD risk factors. During inpatient rehabilitation, 96 stroke patients were screened for DS. After 6 months, 71 patients were attainable for a follow-up. DS was assessed using the 15-item Geriatric Depression Scale (GDS-15). At follow-up a telephone interview that included the Structured Clinical Interview for Psychiatric Disorders (SCID), which is based on DSM-IV criteria, and the GDS-15 was conducted. Patients with major depression (MD) at the follow-up were considered to have PSD. Regression analyses were conducted to examine the influence of early DS on PSD after 6 months while controlling for age, premorbid depression, and functional and cognitive impairments. The percentage of patients who scored above the GDS-15 cut-off for clinically relevant DS increased significantly, from 37% to 44%, after 6 months. According to the SCID, 27% of stroke patients fulfilled the criteria for MD, and another 16% fulfilled those for minor depression. Logistic regression showed that DS at baseline significantly predicted PSD at follow-up (odds ratio: 1.43; 95% CI: 1.15-1.8). Self-reported DS during inpatient rehabilitation are predictive for PSD 6 months after discharge. Assessment of early DS contributes to identifying stroke patients at risk for PSD, thereby facilitating prevention and treatment.

A More-than-Social Movement: The Post-Human Condition of Quality in the Early Years

ERIC Educational Resources Information Center

Arndt, Sonja; Tesar, Marek

2016-01-01

This article explores quality in early childhood education by de-elevating the importance of the human subject and experience, and heightening instead a focus on and tensions with the post-human. The argument traces the intricate web of "qualities" woven throughout entanglements of subjects, objects and things that constitute what is…

The effect of different coating materials on the prevention of powder bounce in the next generation impactor

PubMed Central

Khalili, Shadi Farshbaf; Ghanbarzadeh, Saeed; Nokhodchi, Ali; Hamishehkar, Hamed

2018-01-01

In the process of quality control of pulmonary drug delivery products, aerosolization efficiency is mainly determined using impactors, e.g. next generation impactor (NGI). However, particle bounce may interfere with the validity and accuracy of results due to the overestimation of the respirable fraction. It is suggested that the coating of impactor's stages may prevent the particle bounce. Therefore, coating materials may influence the results of the aerosolization indexes of pulmonary dosage forms. The aim of this study was to investigate if the aerosolization indices are affected differently by using the different coating materials. In this study, the effects of using different materials including Span® 85, Tween® 80, silicon® oil, glycerin and Brij® 35/glycerin mixture recommended for the coating of NGI stages on the aerosolization indices such as fine particle fraction, fine particle dose, mass median aerodynamic diameter, and geometric standard deviation of salbutamol emitted from a commercial metered dose inhaler (MDI), were assessed. Three statistically different results were obtained on using Tween® 80, Span® 85 and silicon oil, and glycerin and Brij®35/glycerin mixture. It can be concluded that the type of coating material influenced the aerosolization indices of the examined MDI in NGIs. PMID:29853937

The effect of different coating materials on the prevention of powder bounce in the next generation impactor.

PubMed

Khalili, Shadi Farshbaf; Ghanbarzadeh, Saeed; Nokhodchi, Ali; Hamishehkar, Hamed

2018-06-01

In the process of quality control of pulmonary drug delivery products, aerosolization efficiency is mainly determined using impactors, e.g. next generation impactor (NGI). However, particle bounce may interfere with the validity and accuracy of results due to the overestimation of the respirable fraction. It is suggested that the coating of impactor's stages may prevent the particle bounce. Therefore, coating materials may influence the results of the aerosolization indexes of pulmonary dosage forms. The aim of this study was to investigate if the aerosolization indices are affected differently by using the different coating materials. In this study, the effects of using different materials including Span ® 85, Tween ® 80, silicon ® oil, glycerin and Brij ® 35/glycerin mixture recommended for the coating of NGI stages on the aerosolization indices such as fine particle fraction, fine particle dose, mass median aerodynamic diameter, and geometric standard deviation of salbutamol emitted from a commercial metered dose inhaler (MDI), were assessed. Three statistically different results were obtained on using Tween ® 80, Span ® 85 and silicon oil, and glycerin and Brij ® 35/glycerin mixture. It can be concluded that the type of coating material influenced the aerosolization indices of the examined MDI in NGIs.

Development of Environmental Load Estimation Model for Road Drainage Systems in the Early Design Phase

NASA Astrophysics Data System (ADS)

Park, Jin-Young; Lee, Dong-Eun; Kim, Byung-Soo

2017-10-01

Due to the increasing concern about climate change, efforts to reduce environmental load are continuously being made in construction industry, and LCA (life cycle assessment) is being presented as an effective method to assess environmental load. Since LCA requires information on construction quantity used for environmental load estimation, however, it is not being utilized in the environmental review in the early design phase where it is difficult to obtain such information. In this study, computation system for construction quantity based on standard cross section of road drainage facilities was developed to compute construction quantity required for LCA using only information available in the early design phase to develop and verify the effectiveness of a model that can perform environmental load estimation. The result showed that it is an effective model that can be used in the early design phase as it revealed a 13.39% mean absolute error rate.

Are We Hoping For A Bounce A Study On Resilience And Human Relations In A High Reliability Organization

DTIC Science & Technology

2016-03-01

A BOUNCE? A STUDY ON RESILIENCE AND HUMAN RELATIONS IN A HIGH RELIABILITY ORGANIZATION by Robert D. Johns March 2016 Thesis Advisor...RELATIONS IN A HIGH RELIABILITY ORGANIZATION 5. FUNDING NUMBERS 6. AUTHOR(S) Robert D. Johns 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES...200 words) This study analyzes the various resilience factors associated with a military high reliability organization (HRO). The data measuring

The evolutionary sequence of post-starburst galaxies

NASA Astrophysics Data System (ADS)

Wilkinson, C. L.; Pimbblet, K. A.; Stott, J. P.

2017-12-01

There are multiple ways in which to select post-starburst galaxies in the literature. In this work, we present a study into how two well-used selection techniques have consequences on observable post-starburst galaxy parameters, such as colour, morphology and environment, and how this affects interpretations of their role in the galaxy duty cycle. We identify a master sample of H δ strong (EWH δ > 3Å) post-starburst galaxies from the value-added catalogue in the seventh data release of the Sloan Digital Sky Survey (SDSS DR7) over a redshift range 0.01 < z < 0.1. From this sample we select two E+A subsets, both having a very little [O II] emission (EW_[O II] > -2.5 Å) but one having an additional cut on EWHα (>-3 Å). We examine the differences in observables and AGN fractions to see what effect the H α cut has on the properties of post-starburst galaxies and what these differing samples can tell us about the duty cycle of post-starburst galaxies. We find that H δ strong galaxies peak in the 'blue cloud', E+As in the 'green valley' and pure E+As in the 'red sequence'. We also find that pure E+As have a more early-type morphology and a higher fraction in denser environments compared with the H δ strong and E+A galaxies. These results suggest that there is an evolutionary sequence in the post-starburst phase from blue discy galaxies with residual star formation to passive red early-types.

Imaging of early acceleration phase of the 2013-2014 Boso slow slip event

NASA Astrophysics Data System (ADS)

Fukuda, J.; Kato, A.; Obara, K.; Miura, S.; Kato, T.

2014-12-01

Based on GPS and seismic data, we examine the spatiotemporal evolution of a slow slip event (SSE) and associated seismic activity that occurred off the Boso peninsula, central Japan, from December 2013 to January 2014. We use GPS data from 71 stations of the GEONET and 6 stations operated by Earthquake Research Institute of the University of Tokyo and Tohoku University around the Boso peninsula. We apply a modified version of the Network Inversion Filter to the GPS time series at the 77 stations to estimate the spatiotemporal evolution of daily cumulative slip and slip rate on the subducting Philippine Sea plate. In addition, we create an improved earthquake catalog by applying a matched filter technique to continuous seismograms and examine the spatiotemporal relations between slow slip and seismicity. We find that the SSE started in early December 2013. The spatiotemporal evolution of slow slip and seismicity is divided into two distinct phases, an earlier slow phase from early to 30 December 2013 (Phase I) and a subsequent faster phase from 30 December 2013 to 9 January 2014 (Phase II). During Phase I, slip accelerated slowly up to a maximum rate of 1.6 m/yr with potentially accelerating　along-strike propagation at speeds on the order of 1 km/day or less and no accompanying seismicity. On the other hand, during Phase II, slip accelerated rapidly up to a maximum rate of 4.5 m/yr and then rapidly decelerated. The slip front propagated along strike at a constant speed of ~10 km/day. During the Phase II, slow slip was accompanied by seismic swarm activity that was highly correlated in space and time with slip rate, suggesting that the swarm activity was triggered by stress loading due to slow slip. Early slow acceleration of slip has not been identified in the past Boso SSEs in 1996, 2002, 2007, and 2011. It is not clear at this point whether the past Boso SSEs started with slow acceleration similarly to the 2013-2014 SSE. The transition from the slow to the

Early-phase musculoskeletal adaptations to different levels of eccentric resistance after 8 weeks of lower body training.

PubMed

English, Kirk L; Loehr, James A; Lee, Stuart M C; Smith, Scott M

2014-11-01

Eccentric muscle actions are important to the development of muscle mass and strength and may affect bone mineral density (BMD). This study's purpose was to determine the relative effectiveness of five different eccentric:concentric load ratios to increase musculoskeletal parameters during early adaptations to resistance training. Forty male subjects performed a supine leg press and calf press training program 3 days week(-1) for 8 weeks. Subjects were matched for pre-training leg press 1-repetition maximum strength (1-RM) and randomly assigned to one of five training groups. Concentric training load (% 1-RM) was constant across groups, but within groups, eccentric load was 0, 33, 66, 100, or 138% of concentric load. Muscle mass (dual energy X-ray absorptiometry; DXA), strength (1-RM), and BMD (DXA) were measured pre- and post-training. Markers of bone metabolism were assessed pre-, mid- and post-training. The increase in leg press 1-RM in the 138% group (20 ± 4%) was significantly greater (P < 0.05) than the 0% (8 ± 3%), 33% (8 ± 5%) and 66% (8 ± 4%) groups, but not the 100% group (13 ± 6 %; P = 0.15). All groups, except the 0% group, increased calf press 1-RM (P < 0.05). Leg lean mass and greater trochanter BMD were increased only in the 138% group (P < 0.05). Early-phase adaptations to eccentric overload training include increases in muscle mass and site-specific increases in BMD and muscle strength which are not present or are less with traditional and eccentric underload training. Eccentric overload provides a robust musculoskeletal stimulus that may benefit bedridden patients, individuals recovering from injury or illness, and astronauts during spaceflight.

Early- and later-phases satellite cell responses and myonuclear content with resistance training in young men.

PubMed

Damas, Felipe; Libardi, Cleiton A; Ugrinowitsch, Carlos; Vechin, Felipe C; Lixandrão, Manoel E; Snijders, Tim; Nederveen, Joshua P; Bacurau, Aline V; Brum, Patricia; Tricoli, Valmor; Roschel, Hamilton; Parise, Gianni; Phillips, Stuart M

2018-01-01

Satellite cells (SC) are associated with skeletal muscle remodelling after muscle damage and/or extensive hypertrophy resulting from resistance training (RT). We recently reported that early increases in muscle protein synthesis (MPS) during RT appear to be directed toward muscle damage repair, but MPS contributes to hypertrophy with progressive muscle damage attenuation. However, modulations in acute-chronic SC content with RT during the initial (1st-wk: high damage), early (3rd-wk: attenuated damage), and later (10th-wk: no damage) stages is not well characterized. Ten young men (27 ± 1 y, 23.6 ± 1.0 kg·m-2) underwent 10-wks of RT and muscle biopsies (vastus-lateralis) were taken before (Pre) and post (48h) the 1st (T1), 5th (T2) and final (T3) RT sessions to evaluate fibre type specific SC content, cross-sectional area (fCSA) and myonuclear number by immunohistochemistry. We observed RT-induced hypertrophy after 10-wks of RT (fCSA increased ~16% in type II, P < 0.04; ~8% in type I [ns]). SC content increased 48h post-exercise at T1 (~69% in type I [P = 0.014]; ~42% in type II [ns]), and this increase was sustained throughout RT (pre T2: ~65%, ~92%; pre T3: ~30% [ns], ~87%, for the increase in type I and II, respectively, vs. pre T1 [P < 0.05]). Increased SC content was not coupled with changes in myonuclear number. SC have a more pronounced role in muscle repair during the initial phase of RT than muscle hypertrophy resulted from 10-wks RT in young men. Chronic elevated SC pool size with RT is important providing proper environment for future stresses or larger fCSA increases.

Perspectives and Open Problems in the Early Phases of Left-Right Patterning

PubMed Central

Vandenberg, Laura N.; Levin, Michael

2009-01-01

Summary Embryonic left-right (LR) patterning is a fascinating aspect of embryogenesis. The field currently faces important questions about the origin of LR asymmetry, the mechanisms by which consistent asymmetry is imposed on the scale of the whole embryo, and the degree of conservation of early phases of LR patterning among model systems. Recent progress on planar cell polarity and cellular asymmetry in a variety of tissues and species provides a new perspective on the early phases of LR patterning. Despite the huge diversity in body-plans over which consistent LR asymmetry is imposed, and the apparent divergence in molecular pathways that underlie laterality, the data reveal conservation of physiological modules among phyla and a basic scheme of cellular chirality amplified by a planar cell polarity-like pathway over large cell fields. PMID:19084609

The Effect of Local and Landscape-Level Characteristics on the Abundance of Forest Birds in Early-Successional Habitats during the Post-Fledging Season in Western Massachusetts

PubMed Central

Labbe, Michelle A.; King, David I.

2014-01-01

Many species of mature forest-nesting birds (“forest birds”) undergo a pronounced shift in habitat use during the post-fledging period and move from their forest nesting sites into areas of early-successional vegetation. Mortality is high during this period, thus understanding the resource requirements of post-fledging birds has implications for conservation. Efforts to identify predictors of abundance of forest birds in patches of early-successional habitats have so far been equivocal, yet these previous studies have primarily focused on contiguously forested landscapes and the potential for landscape-scale influences in more fragmented and modified landscapes is largely unknown. Landscape composition can have a strong influence on the abundance and productivity of forest birds during the nesting period, and could therefore affect the number of forest birds in the landscape available to colonize early-successional habitats during the post-fledging period. Therefore, the inclusion of landscape characteristics should increase the explanatory power of models of forest bird abundance in early-successional habitat patches during the post-fledging period. We examined forest bird abundance and body condition in relation to landscape and habitat characteristics of 15 early-successional sites during the post-fledging season in Massachusetts. The abundance of forest birds was influenced by within-patch habitat characteristics, however the explanatory power of these models was significantly increased by the inclusion of landscape fragmentation and the abundance of forest birds in adjacent forest during the nesting period for some species and age groups. Our findings show that including factors beyond the patch scale can explain additional variation in the abundance of forest birds in early-successional habitats during the post-fledging period. We conclude that landscape composition should be considered when siting early-successional habitat to maximize its benefit to

The effect of local and landscape-level characteristics on the abundance of forest birds in early-successional habitats during the post-fledging season in western Massachusetts.

PubMed

Labbe, Michelle A; King, David I

2014-01-01

Many species of mature forest-nesting birds ("forest birds") undergo a pronounced shift in habitat use during the post-fledging period and move from their forest nesting sites into areas of early-successional vegetation. Mortality is high during this period, thus understanding the resource requirements of post-fledging birds has implications for conservation. Efforts to identify predictors of abundance of forest birds in patches of early-successional habitats have so far been equivocal, yet these previous studies have primarily focused on contiguously forested landscapes and the potential for landscape-scale influences in more fragmented and modified landscapes is largely unknown. Landscape composition can have a strong influence on the abundance and productivity of forest birds during the nesting period, and could therefore affect the number of forest birds in the landscape available to colonize early-successional habitats during the post-fledging period. Therefore, the inclusion of landscape characteristics should increase the explanatory power of models of forest bird abundance in early-successional habitat patches during the post-fledging period. We examined forest bird abundance and body condition in relation to landscape and habitat characteristics of 15 early-successional sites during the post-fledging season in Massachusetts. The abundance of forest birds was influenced by within-patch habitat characteristics, however the explanatory power of these models was significantly increased by the inclusion of landscape fragmentation and the abundance of forest birds in adjacent forest during the nesting period for some species and age groups. Our findings show that including factors beyond the patch scale can explain additional variation in the abundance of forest birds in early-successional habitats during the post-fledging period. We conclude that landscape composition should be considered when siting early-successional habitat to maximize its benefit to forest

Ultra-Early Phase pathologies of Alzheimer's disease and other neurodegenerative diseases.

PubMed

Okazawa, Hitoshi

2017-01-01

The concept of neurodegenerative diseases and the therapeutics targeting these intractable diseases are changing rapidly. Protein aggregation as the top of pathological cascade is now challenged, and many alternative ideas are proposed. Early molecular pathologies before microscopic detection of diseases protein aggregates, which I propose to call "Ultra-Early Phase pathologies or phase 0 pathologies", are the focus of research that might explain the failures of clinical trials with anti-Aβ antibodies against Alzheimer's disease. In this review article, I summarize the critical issues that should be successfully and consistently answered by a new concept of neurodegeneration. For reevaluating old concepts and reconstructing a new concept of neurodegeneration that will replace the old ones, non-biased comprehensive approaches including proteome combined with systems biology analyses will be a powerful tool. I introduce our recent efforts in this orientation that have reached to the stage of non-clinical proof of concept applicable to clinical trials.

Exploring the impact of visual and movement based priming on a motor intervention in the acute phase post-stroke in persons with severe hemiparesis of the upper extremity

PubMed Central

Patel, Jigna; Qiu, Qinyin; Yarossi, Mathew; Merians, Alma; Massood, Supriya; Tunik, Eugene; Adamovich, Sergei; Fluet, Gerard

2016-01-01

Purpose Explore the potential benefits of using priming methods prior to an active hand task in the acute phase post-stroke in persons with severe upper extremity hemiparesis. Methods Five individuals were trained using priming techniques including virtual reality (VR) based visual mirror feedback and contralaterally controlled passive movement strategies prior to training with an active pinch force modulation task. Clinical, kinetic, and neurophysiological measurements were taken pre and post the training period. Clinical measures were taken at six months post training. Results The two priming simulations and active training were well tolerated early after stroke. Priming effects were suggested by increased maximal pinch force immediately after visual and movement based priming. Despite having no clinically observable movement distally, the subjects were able to volitionally coordinate isometric force and muscle activity (EMG) in a pinch tracing task. The Root Mean Square Error (RMSE) of force during the pinch trace task gradually decreased over the training period suggesting learning may have occurred. Changes in motor cortical neurophysiology were seen in the unaffected hemisphere using Transcranial Magnetic Stimulation (TMS) mapping. Significant improvements in motor recovery as measured by the Action Research Arm Test (ARAT) and the Upper Extremity Fugl Meyer Assessment (UEFMA) were demonstrated at six months post training by three of the five subjects. Conclusion This study suggests that an early hand-based intervention using visual and movement based priming activities and a scaled motor task allows participation by persons without the motor control required for traditionally presented rehabilitation and testing. PMID:27636200

Observable induced gravitational waves from an early matter phase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alabidi, Laila; Sasaki, Misao; Kohri, Kazunori

2013-05-01

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 waves induced 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 waves with energy densities within the ranges of both space and earth based gravitational wave detectors.

Renal impairment and heart failure with preserved ejection fraction early post-myocardial infarction

PubMed Central

Jorapur, Vinod; Lamas, Gervasio A; Sadowski, Zygmunt P; Reynolds, Harmony R; Carvalho, Antonio C; Buller, Christopher E; Rankin, James M; Renkin, Jean; Steg, Philippe Gabriel; White, Harvey D; Vozzi, Carlos; Balcells, Eduardo; Ragosta, Michael; Martin, C Edwin; Srinivas, Vankeepuram S; Wharton III, William W; Abramsky, Staci; Mon, Ana C; Kronsberg, Shari S; Hochman, Judith S

2010-01-01

AIM: To study if impaired renal function is associated with increased risk of peri-infarct heart failure (HF) in patients with preserved ejection fraction (EF). METHODS: Patients with occluded infarct-related arteries (IRAs) between 1 to 28 d after myocardial infarction (MI) were grouped into chronic kidney disease (CKD) stages based on estimated glomerular filtration rate (eGFR). Rates of early post-MI HF were compared among eGFR groups. Logistic regression was used to explore independent predictors of HF. RESULTS: Reduced eGFR was present in 71.1% of 2160 patients, with significant renal impairment (eGFR < 60 mL/min every 1.73 m2) in 14.8%. The prevalence of HF was higher with worsening renal function: 15.5%, 17.8% and 29.4% in patients with CKD stages 1, 2 and 3 or 4, respectively (P < 0.0001), despite a small absolute difference in mean EF across eGFR groups: 48.2 ± 10.0, 47.9 ± 11.3 and 46.2 ± 12.1, respectively (P = 0.02). The prevalence of HF was again higher with worsening renal function among patients with preserved EF: 10.1%, 13.6% and 23.6% (P < 0.0001), but this relationship was not significant among patients with depressed EF: 27.1%, 26.2% and 37.9% (P = 0.071). Moreover, eGFR was an independent correlate of HF in patients with preserved EF (P = 0.003) but not in patients with depressed EF (P = 0.181). CONCLUSION: A significant proportion of post-MI patients with occluded IRAs have impaired renal function. Impaired renal function was associated with an increased rate of early post-MI HF, the association being strongest in patients with preserved EF. These findings have implications for management of peri-infarct HF. PMID:20885993

Early follicular phase hormone levels in relation to patterns of alcohol, tobacco, and coffee use.

PubMed

Lucero, J; Harlow, B L; Barbieri, R L; Sluss, P; Cramer, D W

2001-10-01

To examine the effects of alcohol, caffeine, and tobacco use on early follicular phase FSH, LH, E2, and sex hormone-binding globulin (SHBG). Cross-sectional study. Academic medical center. Four hundred ninety-eight women selected from the general population, ages 36-45, who were not currently pregnant, breast feeding, or using exogenous hormones. A general questionnaire assessing demography, anthropometry, and smoking habits and a standardized dietary questionnaire assessing food and beverage frequencies, including sources of alcohol and caffeine. FSH, LH, E2, and SHBG levels measured during the early follicular phase of the menstrual cycle. Significant associations observed in a univariate analysis included age > or =40 and current smoking associated with higher FSH; higher body mass index (BMI) associated with lower SHBG levels; and daily alcohol use, cholesterol consumption greater than the median, and coffee use >1 cup/d associated with higher E2 levels. In a multivariate model, total caffeine use was significantly associated with E2 levels after adjustment for age, BMI, total calories, current smoking, alcohol, cholesterol consumption, and day of sampling. Early follicular phase E2 increased from 28.2 pg/mL for women consuming < or =100 mg of caffeine to 45.2 pg/mL for women consuming > or =500 mg of caffeine per day, about a 70% increase. Coffee consumption and total caffeine use may increase early follicular phase E2 levels independent of related habits of alcohol or tobacco use.

Repulsive gravity induced by a conformally coupled scalar field implies a bouncing radiation-dominated universe

NASA Astrophysics Data System (ADS)

Antunes, V.; Novello, M.

2017-04-01

In the present work we revisit a model consisting of a scalar field with a quartic self-interaction potential non-minimally (conformally) coupled to gravity (Novello in Phys Lett 90A:347 1980). When the scalar field vacuum is in a broken symmetry state, an effective gravitational constant emerges which, in certain regimes, can lead to gravitational repulsive effects when only ordinary radiation is coupled to gravity. In this case, a bouncing universe is shown to be the only cosmological solution admissible by the field equations when the scalar field is in such broken symmetry state.

Efficacy of Early Rehabilitation After Surgical Repair of Acute Aneurysmal Subarachnoid Hemorrhage: Outcomes After Verticalization on Days 2-5 Versus Day 12 Post-Bleeding.

PubMed

Milovanovic, Andjela; Grujicic, Danica; Bogosavljevic, Vojislav; Jokovic, Milos; Mujovic, Natasa; Markovic, Ivana Petronic

2017-01-01

To develop a specific rehabilitation protocol for patients who have undergone surgical repair of acute aneurysmal subarachnoid hemorrhage (aSAH), and to determine the time at which verticalization should be initiated after aSAH. Sixty-five patients who underwent acute-term surgery for aSAH and early rehabilitation were evaluated in groups: Group 1 (n=34) started verticalization on days 2-5 post-bleeding whereas Group 2 (n=31) started verticalization approximately day 12 post-bleeding. All patients were monitored for early complications, vasospasm and ischemia. Assessments of motor status, depression and anxiety (using Zung scales), and cognitive status (using the Mini-Mental State Examination (MMSE)) were conducted at discharge and at 1 and 3 months post-surgery. At discharge, Group 1 had a significantly higher proportion of patients with ischemia than Group 2 (p=0.004). Group 1 had a higher proportion of patients with hemiparesis than Group 2 three months post-surgery (p=0.015). Group 1 patients scored significantly higher on the Zung depression scale than Group 2 patients at 1 month (p=0.005) and 3 months post-surgery (p=0.001; the same applies to the Zung anxiety scale (p=0.006 and p=0.000, respectively). Group 2 patients scored significantly higher on the MMSE than those in Group 1 at discharge (p=0.040) and 1 month post-surgery (p=0.025). Early verticalization had no effect with respect to preventing early postoperative complications in this patient group. Once a patient has undergone acute surgical repair of aSAH, it is safe and preferred that rehabilitation be initiated immediately postsurgery. However, verticalization should not start prior to day 12 post-bleeding.

Functional neuroanatomical correlates of episodic memory impairment in early phase psychosis

PubMed Central

Hummer, Tom A.; Vohs, Jenifer L.; Yung, Matthew G.; Liffick, Emily; Mehdiyoun, Nicole F.; Radnovich, Alexander J.; McDonald, Brenna C.; Saykin, Andrew J.; Breier, Alan

2015-01-01

Studies have demonstrated that episodic memory (EM) is often preferentially disrupted in schizophrenia. The neural substrates that mediate EM impairment in this illness are not fully understood. Several functional magnetic resonance imaging (fMRI) studies have employed EM probe tasks to elucidate the neural underpinnings of impairment, though results have been inconsistent. The majority of EM imaging studies have been conducted in chronic forms of schizophrenia with relatively few studies in early phase patients. Early phase schizophrenia studies are important because they may provide information regarding when EM deficits occur and address potential confounds more frequently observed in chronic populations. In this study, we assessed brain activation during the performance of visual scene encoding and recognition fMRI tasks in patients with earlyphase psychosis (n=35) and age, sex, and race matched healthy control subjects (n = 20). Patients demonstrated significantly lower activation than controls in the right hippocampus and left fusiform gyrus during scene encoding and lower activation in the posterior cingulate, precuneus, and left middle temporal cortex during recognition of target scenes. Symptom levels were not related to the imaging findings, though better cognitive performance in patients was associated with greater right hippocampal activation during encoding. These results provide evidence of altered function in neuroanatomical circuitry subserving EM early in the course of psychotic illness, which may have implications for pathophysiological models of this illness. PMID:25749917

Value of two-phase dynamic multidetector computed tomography in differential diagnosis of post-inflammatory strictures from esophageal cancer

PubMed Central

Karmazanovsky, Grigory G; Buryakina, Svetlana A; Kondratiev, Evgeny V; Yang, Qin; Ruchkin, Dmitry V; Kalinin, Dmitry V

2015-01-01

AIM: To characterize the computed tomography (CT) findings in patients with post-inflammatory esophageal strictures (corrosive and peptic) and reveal the optimal scanning phase protocols for distinguishing post-inflammatory esophageal stricture and esophageal cancer. METHODS: Sixty-five patients with esophageal strictures of different etiology were included in this study: 24 patients with 27 histopathologically confirmed corrosive strictures, 10 patients with 12 peptic strictures and 31 patients with esophageal cancer were evaluated with a two-phase dynamic contrast-enhanced MDCT. Arterial and venous phases at 10 and 35 s after the attenuation of 200 HU were obtained at the descending aorta, with a delayed phase at 6-8 min after the start of injection of contrast media. For qualitative analysis, CT scans of benign strictures were reviewed for the presence/absence of the following features: “target sign”, luminal mass, homogeneity of contrast medium uptake, concentric wall thickening, conically shaped suprastenotic dilatation, smooth boundaries of stenosis and smooth mucous membrane at the transition to stenosis, which were compared with a control group of 31 patients who had esophageal cancer. The quantitative analysis included densitometric parameter acquisition using regions-of-interest measurement of the zone of stenosis and normal esophageal wall and the difference between those measurements (ΔCT) at all phases of bolus contrast enhancement. Esophageal wall thickening, length of esophageal wall thickening and size of the regional lymph nodes were also evaluated. RESULTS: The presence of a concentric esophageal wall, conically shaped suprastenotic dilatation, smooth upper and lower boundaries, “target sign” and smooth mucous membrane at the transition to stenosis were suggestive of a benign cause, with sensitivities of 92.31%, 87.17%, 94.87%, 76.92% and 82.05%, respectively, and specificities of 70.96%, 89.66%, 80.65%, 96.77% and 93.55%, respectively

78 FR 5816 - Guidance for Industry on Clinical Pharmacogenomics: Premarket Evaluation in Early-Phase Clinical...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-28

.... The guidance provides recommendations on when and how genomic principles should be considered and... recommendations on when and how genomic principles should be considered and applied in early-phase clinical... the larger, later adequate, and well-controlled trials (phase 3) that are needed to support marketing...

Measuring disaster recovery: bouncing back or reaching the counterfactual state?

PubMed

Cheng, Shaoming; Ganapati, Emel; Ganapati, Sukumar

2015-07-01

How should one measure the recovery of a locale from a disaster? The measurement is crucial from a public policy and administration standpoint to determine which places should receive disaster assistance, and it affects the performance evaluation of disaster recovery programmes. This paper compares two approaches to measuring recovery: (i) bouncing back to pre-disaster conditions; and (ii) attaining the counterfactual state. The former centres on returning to normalcy following disaster-induced losses, whereas the latter focuses on attaining the state, using quasi-experimental design, which would have existed if the disaster had not occurred. Both are employed here to assess two housing recovery indicators (total new units and their valuations) in Hurricane Katrina-affected counties (rural and urban). The examination reveals significantly different outcomes for the two approaches: counties have not returned to their pre-disaster housing conditions, but they do exhibit counterfactual recovery. Moreover, rural counties may not be as vulnerable as assumed in the disaster recovery literature. © 2015 The Author(s). Disasters © Overseas Development Institute, 2015.

Dark matter and baryogenesis in the Fermi-bounce curvaton mechanism

NASA Astrophysics Data System (ADS)

Addazi, Andrea; Alexander, Stephon; Cai, Yi-Fu; Marcianò, Antonino

2018-05-01

We elaborate on a toy model of matter bounce, in which the matter content is constituted by two fermion species endowed with four fermion interaction terms. We describe the curvaton mechanism that is thus generated, and then argue that one of the two fermionic species may realize baryogenesis, while the other (lighter) one is compatible with constraints on extra hot dark matter particles. The work of AA was partially supported during this collaboration by the MIUR research grant Theoretical Astroparticle Physics PRIN 2012CPPYP7 and by SdC Progetto speciale Multiasse La Società della Conoscenza in Abruzzo PO FSE Abruzzo 2007-2013. The work of YFC is supported in part by the Chinese National Youth Thousand Talents Program (KJ2030220006), by the USTC start-up funding (KY2030000049), by the NSFC (11421303, 11653002), and by the Fund for Fostering Talents in Basic Science of the NSFC (J1310021). AM wishes to acknowledge support by the Shanghai Municipality, through the grant No. KBH1512299, and by Fudan University, through the grant No. JJH1512105

Microgravity collisions of dust aggregates as an analogue to early planetesimal formation

NASA Astrophysics Data System (ADS)

Whizin, Akbar; Blum, Jürgen; Colwell, Joshua

2014-11-01

During the early stages of planet formation the dusty progenitors of planetesimals collided with each other continuously to form the seeds of planets. These collisions could result in growth or disruption depending on the individual impact velocities. Based on input from solar nebula models a laboratory-based microgravity dust collision experiment was developed for a drop tower at the Technische Universität Braunschweig, Germany. We collided 1.0 - 1.6 mm SiO2 dust aggregates with clusters of these aggregates at a range of velocities and mass ratios to determine the thresholds between bouncing, sticking, and fragmentation. Presented here are the results of 264 microgravity collisions occurring at velocities of 1 - 160 cm/s with target-impactor mass ratios of 5:1 to 400:1. We also present the coefficient of restitutions for low-velocity collisions and we find the specific collision energy of fragmentation Q* for aggregates of this size. We find sticking occurs at mass ratios larger than 40:1, but only for low velocities ≤ 3 cm/s, clear boundaries exist for bouncing up to 30 cm/s, and fragmentation at ~50 cm/s and up, with total disruption occurring above 1 m/s.

Post-traumatic stress disorder and cardiovascular disease.

PubMed

Edmondson, Donald; von Känel, Roland

2017-04-01

In this paper, a first in a Series of two, we look at the evidence for an association of post-traumatic stress disorder with incident cardiovascular disease risk and the mechanisms that might cause this association, as well as the prevalence of post-traumatic stress disorder due to cardiovascular disease events and its associated prognostic risk. We discuss research done after the publication of previous relevant systematic reviews, and survey currently funded research from the two most active funders in the field: the National Institutes of Health and the US Veterans Administration. We conclude that post-traumatic stress disorder is a risk factor for incident cardiovascular disease, and a common psychiatric consequence of cardiovascular disease events that might worsen the prognosis of the cardiovascular disease. There are many candidate mechanisms for the link between post-traumatic stress disorder and cardiovascular disease, and several ongoing studies could soon point to the most important behavioural and physiological mechanisms to target in early phase intervention development. Similarly, targets are emerging for individual and environmental interventions that might offset the risk of post-traumatic stress disorder after cardiovascular disease events. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental Verification of Ocean Bounced GPS Signals and Analysis of their Application to Ionospheric Corrections for Satellite Altimetry

NASA Technical Reports Server (NTRS)

Axelrad, P.; Cox, A. E.; Crumpton, K. S.

1997-01-01

An algorithm is presented which uses observations of Global Positioning System (GPS) signals reflected from the ocean surface and acquired by a GPS receiver onboard an altimetric satellite to compute the ionospheric delay present in the altimeter measurement. This eliminates the requirement for a dual frequency altimeter for many Earth observing missions. A ground-based experiment is described which confirms the presence of these ocean-bounced signals and demonstrates the potential for altimeter ionospheric correction at the centimeter level.

High-frequency spectral ultrasound imaging (SUSI) visualizes early post-traumatic heterotopic ossification (HO) in a mouse model.

PubMed

Ranganathan, Kavitha; Hong, Xiaowei; Cholok, David; Habbouche, Joe; Priest, Caitlin; Breuler, Christopher; Chung, Michael; Li, John; Kaura, Arminder; Hsieh, Hsiao Hsin Sung; Butts, Jonathan; Ucer, Serra; Schwartz, Ean; Buchman, Steven R; Stegemann, Jan P; Deng, Cheri X; Levi, Benjamin

2018-04-01

Early treatment of heterotopic ossification (HO) is currently limited by delayed diagnosis due to limited visualization at early time points. In this study, we validate the use of spectral ultrasound imaging (SUSI) in an animal model to detect HO as early as one week after burn tenotomy. Concurrent SUSI, micro CT, and histology at 1, 2, 4, and 9weeks post-injury were used to follow the progression of HO after an Achilles tenotomy and 30% total body surface area burn (n=3-5 limbs per time point). To compare the use of SUSI in different types of injury models, mice (n=5 per group) underwent either burn/tenotomy or skin incision injury and were imaged using a 55MHz probe on VisualSonics VEVO 770 system at one week post injury to evaluate the ability of SUSI to distinguish between edema and HO. Average acoustic concentration (AAC) and average scatterer diameter (ASD) were calculated for each ultrasound image frame. Micro CT was used to calculate the total volume of HO. Histology was used to confirm bone formation. Using SUSI, HO was visualized as early as 1week after injury. HO was visualized earliest by 4weeks after injury by micro CT. The average acoustic concentration of HO was 33% more than that of the control limb (n=5). Spectroscopic foci of HO present at 1week that persisted throughout all time points correlated with the HO present at 9weeks on micro CT imaging. SUSI visualizes HO as early as one week after injury in an animal model. SUSI represents a new imaging modality with promise for early diagnosis of HO. Copyright © 2018 Elsevier Inc. All rights reserved.

Geoeffectiveness during the early phase of Solar Cycle 24

NASA Astrophysics Data System (ADS)

Pande, Bimal

Geoeffectiveness during the early phase of Solar Cycle 24 \\underline{} Abstract\\underline{} It is very important and interesting to understand the solar eruptions because it produces the geoeffectiveness in our Earth environment. In the rise phase of the solar cycle, geoeffective events are less frequent, thus this provide us better opportunity to study these events including the detection of their source regions. Keeping this in mind, we have analysed the data of rise phase of current solar cycle 24 ( 2009-2012). During above time period, we have selected 59 geoeffective events having Disturbance Storm Time (Dst) index < -50 nT. Based on the Dst index, we divided the events into two categories i.e. moderate (< -50 nT > -100 nT ) and intense ( <-100 nT). To locate the solar source regions of geoeffective and SEPs associated events, we have used available images, movies and Solar Geophysical data (SGD) list: for example movies from SOHO/EIT, images and movies from the Solar Dynamic Observatory (SDO). In this study, we will discuss and compare the different properties of associated CMEs, flares and their relation with geoeffectiveness.

Histological features of bone marrow in paediatric patients during the asymptomatic phase of early-stage Black African sickle cell anaemia.

PubMed

Mauriello, Alessandro; Giacobbi, Erica; Saggini, Andrea; Isgrò, Antonella; Facchetti, Simone; Anemona, Lucia

2017-04-01

Bone marrow histological features of sickle cell anaemia (SCA) patients during early stages and in the asymptomatic phase of the disease appear an interesting area of study, representing early-stage consequences of SCA with a close relation to its pathophysiology. Unfortunately, this field of research has never been specifically addressed before. Bone marrow biopsies from 26 consecutive Black African SCA patients (M:F=1.6:1; age 2-17 years), free of clinical signs of chronic bone marrow damage, with no recent history of symptomatic vaso-occlusive episodes, and waiting for haematopoietic stem cell transplantation (HSCT), underwent morphological, immunohistochemical and electron microscopy evaluation. Additional comparison with three bone marrow specimens from post-HSCT SCA patients and 10 bone marrow specimens from AS healthy carriers was performed. Bone marrow of SCA patients was normocellular or slighly hypercellular in all cases. Erythroid hyperplasia was a common feature. Myeloid lineage was slightly decreased with normal to slightly diminished neutrophilic granulocytes; CD68 positive monocytic-macrophagic cells appeared slightly increased, with a predominant CD163 positive M2/M(Hb) phenotype. A positive correlation was found between haemoglobin values and number of bone marrow erythroid cells (R 2 =0.15, p=0.05). Intravascular and interstitial clusters of erythroid sickle cells were found in bone marrow of pre-HSCT homozygous SS SCA patients, as well as heterozygous AS healthy carriers, and the single post-HSCT patient matched to an AS health carrier donor. Copyright © 2017 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.

Fake news and post-truth pronouncements in general and in early human development.

PubMed

Grech, Victor

2017-12-01

Fake news and post-truth pronouncements are increasingly common, and are unfortunately also progressively being applied to the sciences, including the medical sciences. This editorial briefly reviews this unsavoury trend and highlights recent debunking of fake truths in early human development. Science is arguably the last metanarrative with any significant cachet in the postmodern period. We, as scientists, must strive to ensure that our work is transparent and of the highest possible standard so as to continue to uphold science's integrity and probity. Copyright © 2017 Elsevier B.V. All rights reserved.

How they see it: young women's views on early marriage in a post-conflict setting.

PubMed

Knox, Sonya Em

2017-10-01

Current understandings of early marriage in conflict and post-conflict settings are incomplete and under-researched, and do not sufficiently take into consideration the views and experiences of adolescent girls. While much of the literature, development reports and mainstream media emphasise the poverty, health risks and lack of agency of young women married early, they seldom provide these teenagers an open platform from which to speak. In 2007, a Palestinian refugee camp in North Lebanon was destroyed and its residents forced to flee. Returning families experienced extreme hardships and a military cordon. Through ethnographic research undertaken in the camp a year later with adolescent girls in or en route to an early marriage, their mothers and NGO community workers, I explored decision-making processes leading to an early marriage and adolescent brides' assessments of married life. The decision to enter an early marriage, neither unilateral nor imposed, was instead described as an assessment of numerous factors, including economic hardships, insecurity and loneliness, many arising as a result of the conflict. Findings of this study challenge common understandings of early marriage - both the decision and its consequences - and call for greater nuance in designing interventions. These findings are particularly pertinent amid sensationalised media reports of early marriage in Syrian refugee communities; presenting girls in early marriages as victims garners international attention, but is not necessarily an accurate reflection of these girls' own understandings of their situation.

Experimental studies on particle impaction and bounce: effects of substrate design and material

NASA Astrophysics Data System (ADS)

Chang, Mingchih; Kim, Seongheon; Sioutas, Constantinos

This paper presents an experimental investigation of the effects of impaction substrate designs and material in reducing particle bounce and reentrainment. Particle collection without coating by using combinations of different impaction substrate designs and surface materials was conducted using a personal particle sampler (PPS) developed by the University of Southern California. The PPS operates at flow rate of 4 l min -1 with a 50% cutpoint of approximately 0.9 μm in aerodynamic diameter. The laboratory results showed that the PPS collection efficiency for particles larger than 50% cutpoint is strikingly low (e.g., less than 50%) when an uncoated open cavity made of aluminum was used as an impaction substrate. The collection efficiency gradually increased when Teflon tape, Nuclepore, and glass fiber filters were used as impaction surfaces, respectively. Conical or partially enclosed cavity substrate designs increased collection efficiency of particles of 9 μm up to 80-90%. A conical cavity with glass fiber filter used as impaction surface was identified as the optimum configuration, resulting in a collection efficiency of 92% at Stokes numbers as high as 15.4 (corresponding to 9 μm in aerodynamic diameter). Particle losses were low (less than 10%) and relatively independent of particle size in any design with glass fiber filter. Losses seemed to increase slightly with particle size in all other configurations. Finally, outdoor PM 1 concentrations obtained with the PPS (in its optimum configuration) and a modified micro-orifice uniform deposit impactor (MOUDI) with coated impaction stages were in excellent agreement. The mean ratio of the PPS-to-MOUDI concentration was 1.13(±0.17) with a correlation coefficient R2=0.95. Results from this investigation can be readily applied to design particle bounce-free impaction substrates without the use of coating. This is a very important feature of impactors, especially when chemical analysis of the collected particulate

Integrating post-manufacturing issues into design and manufacturing decisions

NASA Technical Reports Server (NTRS)

Eubanks, Charles F.

1996-01-01

An investigation is conducted on research into some of the fundamental issues underlying the design for manufacturing, service and recycling that affect engineering decisions early in the conceptual design phase of mechanical systems. The investigation focuses on a system-based approach to material selection, manufacturing methods and assembly processes related to overall product requirements, performance and life-cycle costs. Particular emphasis is placed on concurrent engineering decision support for post-manufacturing issues such as serviceability, recyclability, and product retirement.

Bouncing Continents: Insights into the Physics of the Polar Regions of the Earth from the POLENET Project in the International Polar Year

ERIC Educational Resources Information Center

Reading, Anya M.

2008-01-01

When ice sheets melt, and reduce the load on the surface of the Earth, the land areas beneath them bounce back up. New, accurate observations are needed to investigate this uplift and its implications effectively. This article provides a topical starting point for investigating some applications of physics applied to the polar regions of the…

Early spring post-fire snow albedo dynamics in high latitude boreal forests using Landsat-8 OLI data

PubMed Central

Wang, Zhuosen; Erb, Angela M.; Schaaf, Crystal B.; Sun, Qingsong; Liu, Yan; Yang, Yun; Shuai, Yanmin; Casey, Kimberly A.; Román, Miguel O.

2018-01-01

Taking advantage of the improved radiometric resolution of Landsat-8 OLI which, unlike previous Landsat sensors, does not saturate over snow, the progress of fire recovery progress at the landscape scale (< 100m) is examined. High quality Landsat-8 albedo retrievals can now capture the true reflective and layered character of snow cover over a full range of land surface conditions and vegetation densities. This new capability particularly improves the assessment of post-fire vegetation dynamics across low- to high- burn severity gradients in Arctic and boreal regions in the early spring, when the albedos during recovery show the greatest variation. We use 30 m resolution Landsat-8 surface reflectances with concurrent coarser resolution (500m) MODIS high quality full inversion surface Bidirectional Reflectance Distribution Functions (BRDF) products to produce higher resolution values of surface albedo. The high resolution full expression shortwave blue sky albedo product performs well with an overall RMSE of 0.0267 between tower and satellite measures under both snow-free and snow-covered conditions. While the importance of post-fire albedo recovery can be discerned from the MODIS albedo product at regional and global scales, our study addresses the particular importance of early spring post-fire albedo recovery at the landscape scale by considering the significant spatial heterogeneity of burn severity, and the impact of snow on the early spring albedo of various vegetation recovery types. We found that variations in early spring albedo within a single MODIS gridded pixel can be larger than 0.6. Since the frequency and severity of wildfires in Arctic and boreal systems is expected to increase in the coming decades, the dynamics of albedo in response to these rapid surface changes will increasingly impact the energy balance and contribute to other climate processes and physical feedback mechanisms. Surface radiation products derived from Landsat-8 data will thus

Early Spring Post-Fire Snow Albedo Dynamics in High Latitude Boreal Forests Using Landsat-8 OLI Data

NASA Technical Reports Server (NTRS)

Wang, Zhuosen; Erb, Angela M.; Schaaf, Crystal B.; Sun, Qingsong; Liu, Yan; Yang, Yun; Shuai, Yanmin; Casey, Kimberly A.; Roman, Miguel O.

2016-01-01

Taking advantage of the improved radiometric resolution of Landsat-8 OLI which, unlike previous Landsat sensors, does not saturate over snow, the progress of fire recovery progress at the landscape scale (less than 100 m) is examined. High quality Landsat-8 albedo retrievals can now capture the true reflective and layered character of snow cover over a full range of land surface conditions and vegetation densities. This new capability particularly improves the assessment of post-fire vegetation dynamics across low- to high-burn severity gradients in Arctic and boreal regions in the early spring, when the albedos during recovery show the greatest variation. We use 30 m resolution Landsat-8 surface reflectances with concurrent coarser resolution (500 m) MODIS high quality full inversion surface Bidirectional Reflectance Distribution Functions (BRDF) products to produce higher resolution values of surface albedo. The high resolution full expression shortwave blue sky albedo product performs well with an overall RMSE of 0.0267 between tower and satellite measures under both snow-free and snow-covered conditions. While the importance of post-fire albedo recovery can be discerned from the MODIS albedo product at regional and global scales, our study addresses the particular importance of early spring post-fire albedo recovery at the landscape scale by considering the significant spatial heterogeneity of burn severity, and the impact of snow on the early spring albedo of various vegetation recovery types. We found that variations in early spring albedo within a single MODIS gridded pixel can be larger than 0.6. Since the frequency and severity of wildfires in Arctic and boreal systems is expected to increase in the coming decades, the dynamics of albedo in response to these rapid surface changes will increasingly impact the energy balance and contribute to other climate processes and physical feedback mechanisms. Surface radiation products derived from Landsat-8 data will

Early spring post-fire snow albedo dynamics in high latitude boreal forests using Landsat-8 OLI data.

PubMed

Wang, Zhuosen; Erb, Angela M; Schaaf, Crystal B; Sun, Qingsong; Liu, Yan; Yang, Yun; Shuai, Yanmin; Casey, Kimberly A; Román, Miguel O

2016-11-01

Taking advantage of the improved radiometric resolution of Landsat-8 OLI which, unlike previous Landsat sensors, does not saturate over snow, the progress of fire recovery progress at the landscape scale (< 100m) is examined. High quality Landsat-8 albedo retrievals can now capture the true reflective and layered character of snow cover over a full range of land surface conditions and vegetation densities. This new capability particularly improves the assessment of post-fire vegetation dynamics across low- to high- burn severity gradients in Arctic and boreal regions in the early spring, when the albedos during recovery show the greatest variation. We use 30 m resolution Landsat-8 surface reflectances with concurrent coarser resolution (500m) MODIS high quality full inversion surface Bidirectional Reflectance Distribution Functions (BRDF) products to produce higher resolution values of surface albedo. The high resolution full expression shortwave blue sky albedo product performs well with an overall RMSE of 0.0267 between tower and satellite measures under both snow-free and snow-covered conditions. While the importance of post-fire albedo recovery can be discerned from the MODIS albedo product at regional and global scales, our study addresses the particular importance of early spring post-fire albedo recovery at the landscape scale by considering the significant spatial heterogeneity of burn severity, and the impact of snow on the early spring albedo of various vegetation recovery types. We found that variations in early spring albedo within a single MODIS gridded pixel can be larger than 0.6. Since the frequency and severity of wildfires in Arctic and boreal systems is expected to increase in the coming decades, the dynamics of albedo in response to these rapid surface changes will increasingly impact the energy balance and contribute to other climate processes and physical feedback mechanisms. Surface radiation products derived from Landsat-8 data will thus

Midodrine as a Countermeasure for Post-Spaceflight Orthostatic Hypotension

NASA Technical Reports Server (NTRS)

Stenger, Michael B.; Stein, Sydney P.; Meck, Janice V.; Platts, Steven H.

2008-01-01

One possible mechanism for post-spaceflight orthostatic hypotension, which affects approximately 30% of astronauts after short duration shuttle missions, is inadequate norepinephrine release during upright posture. We performed a two phased study to determine the effectiveness of an alpha1-adrenergic agonist, midodrine, as a countermeasure to post-spaceflight orthostatic hypotension. The first phase of the study examined the landing day orthostatic responses of six veteran astronauts after oral midodrine (10 mg) administered on the ground within approximately two hours of wheel stop. One female crewmember exhibited orthostatic hypotension in a previous flight but not after midodrine. Five male crewmembers, who did not exhibit orthostatic hypotension during previous flights, also did not show signs of orthostatic hypotension after midodrine. Additionally, phase one showed that midodrine did not cause hypertension in these crewmembers. In the second phase of this study, midodrine is ingested inflight (near time of ignition, TIG) and orthostatic responses are determined immediately upon landing via an 80 degree head-up tilt test performed on the crew transport vehicle (CTV). Four of ten crewmembers have completed phase two of this study. Two crewmembers completed the landing day tilt tests, while two tests were ended early due to presyncopal symptoms. All subjects had decreased landing day stroke volumes and increased heart rates compared to preflight. Midodrine appears to have increased total peripheral resistance in one crewmember who was able to complete the landing day tilt test. The effectiveness of midodrine as a countermeasure to immediate post-spaceflight orthostatic hypotension has yet to be determined; interpretation is made more difficult due to low subject number and the lack of control subjects on the CTV.

Essential Elements of Early Post Discharge Care of Patients with Heart Failure.

PubMed

Soucier, Richard J; Miller, P Elliott; Ingrassia, Joseph J; Riello, Ralph; Desai, Nihar R; Ahmad, Tariq

2018-06-01

Heart failure is associated with an enormous burden on both patients and health care systems in the USA. Several national policy initiatives have focused on improving the quality of heart failure care, including reducing readmissions following hospitalization, which are common, costly, and, at least in part, preventable. The transition from inpatient to ambulatory care setting and the immediate post-hospitalization period present an opportunity to further optimize guideline concordant medical therapy, identify reversible issues related to worsening heart failure, and evaluate prognosis. It can also provide opportunities for medication reconciliation and optimization, consideration of device-based therapies, appropriate management of comorbidities, identification of individual barriers to care, and a discussion of goals of care based on prognosis. Recent studies suggest that attention to detail regarding patient comorbidities, barriers to care, optimization of both diuretic and neurohormonal therapies, and assessment of prognosis improve patient outcomes. Despite the fact that the transition period appears to be an optimal time to address these issues in a comprehensive manner, most patients are not referred to programs specializing in this approach post hospital discharge. The objective of this review is to provide an outline for early post discharge care that allows clinicians and other health care providers to care for these heart failure patients in a manner that is both firmly rooted in the guidelines and patient-centered. Data regarding which intervention is most likely to confer benefit to which subset of patients with this disease is lacking and warrants further study.

Decreased endometrial vascularity and receptivity in unexplained recurrent miscarriage patients during midluteal and early pregnancy phases.

PubMed

Tan, Shu-Yin; Hang, Fu; Purvarshi, Gowreesunkur; Li, Min-Qing; Meng, Da-Hua; Huang, Ling-Ling

2015-10-01

To evaluate the predictive value of three-dimensional (3D)-power Doppler sonography on recurrent miscarriage. The study patients were divided into a recurrent miscarriage group (30 cases) and a normal pregnancy group (21 cases). Measurement of endometrial thickness was performed using two-dimensional transvaginal ultrasound in the midluteal phase. The endometrial volume, vascularization index (VI), flow index (FI), and vascularization-flow index (VFI) in midluteal and placenta volume, as well as the VI, FI, and VFI of early pregnancy were measured using Virtual Organ Computer-aided Analysis of 3D-power Doppler ultrasound. Endometrial thickness, endometrial volume, endometrial vascular data, VI, FI, and VFI of the midluteal phase were lower in the recurrent miscarriage group compared with the normal pregnancy group (p < 0.05). Placental volume, VI, and VFI during early pregnancy were lower in the miscarriage group compared with the normal pregnancy group (p < 0.05). There was no significant change in FI between the recurrent miscarriage and control groups during early pregnancy (p > 0.05). The predictive accuracy of endometrial thickness, endometrial volume, VI, FI, and VFI in the midluteal phase, and placenta volume, VI, FI, and VFI in early pregnancy as measured by the receiver operating characteristic curve to predict miscarriage before 12 gestational weeks in participants was 0.681, 0.876, 0.770, 0.720, 0.879, 0.771, 0.907, 0.592, respectively. The 3D-power Doppler ultrasound is a more comprehensive and sensitive method for evaluating endometrial receptivity. Endometrial volume, VI, FI, and VFI in the midluteal phase, as well as VI in early pregnancy, can be considered as predictive factors for recurrent miscarriage. Copyright © 2015. Published by Elsevier B.V.

Electrophoretic serum protein fraction profile during the different physiological phases in Comisana ewes.

PubMed

Piccione, G; Alberghina, D; Marafioti, S; Giannetto, C; Casella, S; Assenza, A; Fazio, F

2012-08-01

The aim of this study was to evaluate the influence of different physiological phases on serum total proteins and their fractions of ten Comisana ewes housed in Mediterranean area. From each animal, blood samples were collected at different physiological phases: late pregnancy, post-partum, early, mid-, end lactation and dry period. On all samples serum total proteins were determined by the biuret method, and albumin, α-globulins, β(1) -globulins, β(2) -globulins and γ-globulins concentrations were assessed using an automated system. One-way repeated measures analysis of variance was applied to determine the significant effect of different physiological phases on the parameters studied. During the late pregnancy and post-partum, total proteins, β1- and β2-globulins and γ-globulins showed the highest values. Starting from post-partum, α-globulins increased to reach their peaks in mid-lactation. Early lactation was characterized by low γ-globulins values. The increase in serum albumin concentration and the drop in some globulin fractions determined the significant increase in albumin/globulin ratio. The obtained results contributed to improve the knowledge on electrophoretic profile during the different physiological phases in ewes, confirming that pregnancy and lactation periods affect the protein metabolism. Particularly, serum protein fractions pattern could give information about dehydration, plasma volume expansion and hepatic function, which occur during the different physiological phases. Dynamics of the protein profile - from pregnancy to dry period - which are provided by our results, could be considered as guidelines for the management strategies to guarantee the nutritional needs of these animals during the different physiological phases and to avoid a decline of productive performance and consequently an economic loss. © 2011 Blackwell Verlag GmbH.

A phase II trial for the efficacy of physiotherapy intervention for early-onset hip osteoarthritis: study protocol for a randomised controlled trial.

PubMed

Kemp, Joanne L; Moore, Kate; Fransen, Marlene; Russell, Trevor G; Crossley, Kay M

2015-01-27

Early-onset hip osteoarthritis is commonly seen in people undergoing hip arthroscopy and is associated with increased pain, reduced ability to participate in physical activity, reduced quality of life and reduced range of motion and muscle strength. Despite this, the efficacy of non-surgical interventions such as exercise therapies remains unknown. The primary aim is to establish the feasibility of a phase III randomised controlled trial investigating a targeted physiotherapy intervention for people with early-onset hip osteoarthritis. The secondary aims are to determine the size of treatment effects of a physiotherapy intervention, targeted to improve hip joint range and hip-related symptoms in early-onset hip osteoarthritis following hip arthroscopy, compared to a health-education control. This protocol describes a randomised, assessor- and participant-blind, controlled clinical trial. We will include 20 participants who are (i) aged between 18 and 50 years; (ii) have undergone hip arthroscopy during the past six to 12 months; (iii) have early-onset hip osteoarthritis (defined as chondrolabral pathology) at the time of hip arthroscopy; and (iv) experience hip-related pain during activities. Primary outcome will be the feasibility of a phase III clinical trial. Secondary outcomes will be (i) perceived global change score; (ii) hip-related symptoms (measured using the Hip disability and Osteoarthritis Outcome Score (HOOS) pain subscale, activity subscale, and sport and recreation subscale); (iii) hip quality of life (measured using the HOOS quality of life subscale and International Hip Outcome tool; (iv) hip muscle strength and (v) hip range of motion. The physiotherapy intervention is semi-standardised, including joint and soft tissue mobilisation and stretching, hip and trunk muscle retraining and functional and activity-specific retraining and education. The control intervention encompasses individualised health education, with the same frequency and duration

Prediction of acute renal allograft rejection in early post-transplantation period by soluble CD30.

PubMed

Dong, Wang; Shunliang, Yang; Weizhen, Wu; Qinghua, Wang; Zhangxin, Zeng; Jianming, Tan; He, Wang

2006-06-01

To evaluate the feasibility of serum sCD30 for prediction of acute graft rejection, we analyzed clinical data of 231 patients, whose serum levels of sCD30 were detected by ELISA before and after transplantation. They were divided into three groups: acute rejection group (AR, n = 49), uncomplicated course group (UC, n = 171) and delayed graft function group (DGF, n = 11). Preoperative sCD30 levels of three groups were 183 +/- 74, 177 +/- 82 and 168 +/- 53 U/ml, respectively (P = 0.82). Significant decrease of sCD30 was detected in three groups on day 5 and 10 post-transplantation respectively (52 +/- 30 and 9 +/- 5 U/ml respectively, P < 0.001). Compared with Group UC and DGF, patients of Group AR had higher sCD30 values on day 5 post-transplantation (92 +/- 27 U/ml vs. 41 +/- 20 U/ml and 48 +/- 18 U/ml, P < 0.001). However, sCD30 levels on day 10 post-transplantation were virtually similar in patients of three groups (P = 0.43). Receiver operating characteristic (ROC) curve demonstrated that sCD30 level on day 5 post-transplantation could differentiate patients who subsequently suffered acute allograft rejection from others (area under ROC curve 0.95). According to ROC curve, 65 U/ml may be the optimal operational cut-off level to predict impending graft rejection (specificity 91.8%, sensitivity 87.1%). Measurement of soluble CD30 on day 5 post-transplantation might offer a noninvasive means to recognize patients at risk of impending acute graft rejection during early post-transplantation period.

Can we obtain the coefficient of restitution from the sound of a bouncing ball?

NASA Astrophysics Data System (ADS)

Heckel, Michael; Glielmo, Aldo; Gunkelmann, Nina; Pöschel, Thorsten

2016-03-01

The coefficient of restitution may be determined from the sound signal emitted by a sphere bouncing repeatedly off the ground. Although there is a large number of publications exploiting this method, so far, there is no quantitative discussion of the error related to this type of measurement. Analyzing the main error sources, we find that even tiny deviations of the shape from the perfect sphere may lead to substantial errors that dominate the overall error of the measurement. Therefore, we come to the conclusion that the well-established method to measure the coefficient of restitution through the emitted sound is applicable only for the case of nearly perfect spheres. For larger falling height, air drag may lead to considerable error, too.

Effects of temperature on early-phase transmission of Yersina pestis by the flea, Xenopsylla cheopis.

PubMed

Schotthoefer, Anna M; Bearden, Scott W; Vetter, Sara M; Holmes, Jennifer; Montenieri, John A; Graham, Christine B; Woods, Michael E; Eisen, Rebecca J; Gage, Kenneth L

2011-03-01

Sharp declines in human and animal cases of plague, caused by the bacterium Yersinia pestis (Yersin), have been observed when outbreaks coincide with hot weather. Failure of biofilm production, or blockage, to occur in the flea, as temperatures reach 30 degrees C has been suggested as an explanation for these declines. Recent work demonstrating efficient flea transmission during the first few days after fleas have taken an infectious blood meal, in the absence of blockage (e.g., early-phase transmission), however, has called this hypothesis into question. To explore the potential effects of temperature on early-phase transmission, we infected colony-reared Xenopsylla cheopis (Rothchild) fleas with a wild-type strain of plague bacteria using an artificial feeding system, and held groups of fleas at 10, 23, 27, and 30 degrees C. Naive Swiss Webster mice were exposed to fleas from each of these temperatures on days 1-4 postinfection, and monitored for signs of infection for 21 d. Temperature did not significantly influence the rates of transmission observed for fleas held at 23, 27, and 30 degrees C. Estimated per flea transmission efficiencies for these higher temperatures ranged from 2.32 to 4.96% (95% confidence interval [CI]: 0.96-8.74). In contrast, no transmission was observed in mice challenged by fleas held at 10 degrees C (per flea transmission efficiency estimates, 0-1.68%). These results suggest that declines in human and animal cases during hot weather are not related to changes in the abilities of X. cheopis fleas to transmit Y. pestis infections during the early-phase period. By contrast, transmission may be delayed or inhibited at low temperatures, indicating that epizootic spread of Y. pestis by X. cheopis via early-phase transmission is unlikely during colder periods of the year.

Multi-phase post-mortem CT-angiography: a pathologic correlation study on cardiovascular sudden death

PubMed Central

Turillazzi, Emanuela; Frati, Paola; Pascale, Natascha; Pomara, Cristoforo; Grilli, Giampaolo; Viola, Rocco Valerio; Fineschi, Vittorio

2016-01-01

Multi-phase post-mortem CT-angiography (MPMCTA) has the great potential to increase the quality of the post-mortem investigation, especially in the area of sudden death; however, its role as routine complement to the pathology toolbox is still questioned as it needs to be further standardized. The aim of this study is to investigate the contribution of MPMCTA in cases of sudden unexplained death in adults and in particular in sudden cardiovascular death. Sixty-eight sudden unexpected deaths of adults were investigated at our institution between 2012 and 2013. Ten cases underwent MPMCTA and autopsy and were included in the study. Before the angiographic step by complete filling of the vascular system, prior to any manipulation of the body, a non-contrast CT-scan was carried out. Image reconstructions were performed on a CT workstation (Vitrea) and two radiologists experienced with post mortem imaging interpreted the MPMCTA findings. In all 10 cases, we could state a good correlation between combination of post-mortem CT and MPMCTA and autopsy procedures, confirming a high diagnostic sensitivity. With this case series we want to illustrate the advantages offered by performing MPMCTA when facing a sudden death, regardless of specific suspicion for acute coronary syndrome or other vascular or ischemic disease. PMID:27928228

Early phase drugs and biologicals clinical trials on worldwide leading causes of death: a descriptive analysis.

PubMed

Dal-Ré, Rafael

2011-06-01

To describe the global effort targeting the major causes of mortality in terms of "open" early phase clinical trials with drugs and biologicals. Sixteen of the 20 leading causes of death were chosen; 9 of these were also amongst the top 10 causes of death in low-income countries. Studies were identified from the ClinicalTrials.gov database and included phase 1 and/or 2 "interventional" "open" trials, i.e. those recruiting or about to start recruitment. Trials were considered in terms of sponsorship [industry, universities and other organisations (UNO), and US federal agencies (NIH included)], genders and age groups included, and whether they were conducted with drugs and/or biologicals. The search was performed in March 2010. A total of 2,298 (824 phase 1; 1,474 phase 2) trials were retrieved. Of these, 67% were on trachea, bronchus, and lung cancers (25%); diabetes mellitus (15%); colon and rectum cancers (14%); and HIV/AIDS (12%). In contrast, only 4% were trials on diarrhoeal disease, nephrosis and nephritis, liver cirrhosis, and prematurity and low birth weight. UNO were the first source of funding. Fifty-two percent of phase 1 non-cancer trials were on healthy volunteers. Twenty-nine percent of all trials were co-funded. There were 4.6 times as many drug trials as those with biologicals. Only 7% were conducted with a combination of drugs and biologicals, the majority (78%) on cancers. Discrimination in terms of gender or age group was not observed. Four of the 16 diseases considered represented 2/3 of early phase trials. Cancers were a top priority for all sponsors. Increasing attention should be given to conditions with current and projected global high mortality rates that had few "open" early phase trials.

Comparison of Quantitative Characteristics of Early Post-resuscitation EEG Between Asphyxial and Ventricular Fibrillation Cardiac Arrest in Rats.

PubMed

Chen, Bihua; Chen, Gang; Dai, Chenxi; Wang, Pei; Zhang, Lei; Huang, Yuanyuan; Li, Yongqin

2018-04-01

Quantitative electroencephalogram (EEG) analysis has shown promising results in studying brain injury and functional recovery after cardiac arrest (CA). However, whether the quantitative characteristics of EEG, as potential indicators of neurological prognosis, are influenced by CA causes is unknown. The purpose of this study was designed to compare the quantitative characteristics of early post-resuscitation EEG between asphyxial CA (ACA) and ventricular fibrillation CA (VFCA) in rats. Thirty-two Sprague-Dawley rats of both sexes were randomized into either ACA or VFCA group. Cardiopulmonary resuscitation was initiated after 5-min untreated CA. Characteristics of early post-resuscitation EEG were compared, and the relationships between quantitative EEG features and neurological outcomes were investigated. Compared with VFCA, serum level of S100B, neurological deficit score and brain histopathologic damage score were dramatically higher in the ACA group. Quantitative measures of EEG, including onset time of EEG burst, time to normal trace, burst suppression ratio, and information quantity, were significantly lower for CA caused by asphyxia and correlated with the 96-h neurological outcome and survival. Characteristics of earlier post-resuscitation EEG differed between cardiac and respiratory causes. Quantitative measures of EEG not only predicted neurological outcome and survival, but also have the potential to stratify CA with different causes.

Early experimental and clinical experience with a focal implant for lower extremity post-angioplasty dissection.

PubMed

Schneider, Peter A; Giasolli, Robert; Ebner, Adrian; Virmani, Renu; Granada, Juan F

2015-02-01

This study provides preliminary data on the safety and feasibility of the use of a novel focal implant for managing post-percutaneous transluminal balloon angioplasty (post-PTA) dissection. Post-PTA dissection of the lower extremity arteries is managed with stent placement. This provides an acceptable post-intervention result but has long-term disadvantages, such as in-stent restenosis. Focal treatment of post-PTA dissection and avoidance of stents are the objectives of the Tack-It (Intact Vascular, Inc., Wayne, Pennsylvania) device. A preclinical study and first-in-human data are presented. Seven swine underwent superficial femoral artery device placement, with a self-expanding nitinol stent on 1 side and a series of 4 Tack-It devices on the other side. Specimens were harvested at 28 days. The clinical study included 15 limbs that underwent revascularization for critical limb ischemia (n = 9) or claudication (n = 6). Twenty-five lesions were treated in the superficial femoral (n = 8), popliteal (n = 7), and tibial (n = 10) arteries. The preclinical study demonstrated a reduction in stenosis with the Tack-It (16.8 ± 2.6%) compared with stents (46.4 ± 9.8%). Neointimal thickness and injury score decreased with the Tack-It. Clinically, Tack-It placement resulted in acute technical success with resolution of the post-PTA dissection in 100% of lesions. There were no device-related complications or major amputations. Eighteen of the 25 lesions were available for angiographic follow-up at 1-year, and patency was 83.3%. Preclinical data suggest that the Tack-It device causes minimal vessel injury. Clinical use of the Tack-It to manage post-PTA dissection was safe and feasible in this early study and resulted in apposition of dissection flaps without stent placement. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Early intervention for post-traumatic stress disorder.

PubMed

Bryant, Richard A

2007-02-01

The potentially debilitating effect of posttraumatic stress disorder (PTSD) has created much interest in early intervention strategies that can reduce PTSD. This review critiques the evidence for psychological debriefing approaches and alternate early intervention strategies. The review critiques the randomized controlled trials of psychological debriefing, and early provision of cognitive behavior therapy. The latter approach involves therapy attention on acutely traumatized individuals who are high risk for PTSD development, and particularly in people with acute stress disorder (ASD). Psychological debriefing does not prevent PTSD. Cognitive behaviour therapy strategies have proven efficacy in reducing subsequent PTSD in ASD populations. Despite the promising evidence for early provision of CBT, many people do not benefit from CBT. This review concludes with consideration of major challenges facing early intervention approaches in the context of terrorist attacks and mass disasters.

Identifying MRI markers to evaluate early treatment-related changes post-laser ablation for cancer pain management

NASA Astrophysics Data System (ADS)

Tiwari, Pallavi; Danish, Shabbar; Madabhushi, Anant

2014-03-01

Laser interstitial thermal therapy (LITT) has recently emerged as a new treatment modality for cancer pain management that targets the cingulum (pain center in the brain), and has shown promise over radio-frequency (RF) based ablation which is reported to provide temporary relief. One of the major advantages enjoyed by LITT is its compatibility with magnetic resonance imaging (MRI), allowing for high resolution in vivo imaging to be used in LITT procedures. Since laser ablation for pain management is currently exploratory and is only performed at a few centers worldwide, its short-, and long-term effects on the cingulum are currently unknown. Traditionally treatment effects are evaluated by monitoring changes in volume of the ablation zone post-treatment. However, this is sub-optimal since it involves evaluating a single global parameter (volume) to detect changes pre-, and post-MRI. Additionally, the qualitative observations of LITT-related changes on multi-parametric MRI (MPMRI) do not specifically address differentiation between the appearance of treatment related changes (edema, necrosis) from recurrence of the disease (pain recurrence). In this work, we explore the utility of computer extracted texture descriptors on MP-MRI to capture early treatment related changes on a per-voxel basis by extracting quantitative relationships that may allow for an in-depth understanding of tissue response to LITT on MRI, subtle changes that may not be appreciable on original MR intensities. The second objective of this work is to investigate the efficacy of different MRI protocols in accurately capturing treatment related changes within and outside the ablation zone post-LITT. A retrospective cohort of studies comprising pre- and 24-hour post-LITT 3 Tesla T1-weighted (T1w), T2w, T2-GRE, and T2-FLAIR acquisitions was considered. Our scheme involved (1) inter-protocol as well as inter-acquisition affine registration of pre- and post-LITT MRI, (2) quantitation of MRI parameters

Effect of impurities and post-experimental purification in SAD phasing with serial femtosecond crystallography data.

PubMed

Zhang, Tao; Gu, Yuanxin; Fan, Haifu

2016-06-01

In serial crystallography (SX) with either an X-ray free-electron laser (XFEL) or synchrotron radiation as the light source, huge numbers of micrometre-sized crystals are used in diffraction data collection. For a SAD experiment using a derivative with introduced heavy atoms, it is difficult to completely exclude crystals of the native protein from the sample. In this paper, simulations were performed to study how the inclusion of native crystals in the derivative sample could affect the result of SAD phasing and how the post-experimental purification proposed by Zhang et al. [(2015), Acta Cryst. D71, 2513-2518] could be used to remove the impurities. A gadolinium derivative of lysozyme and the corresponding native protein were used in the test. Serial femtosecond crystallography (SFX) diffraction snapshots were generated by CrystFEL. SHELXC/D, Phaser, DM, ARP/wARP and REFMAC were used for automatic structure solution. It is shown that a small amount of impurities (snapshots from native crystals) in the set of derivative snapshots can strongly affect the SAD phasing results. On the other hand, post-experimental purification can efficiently remove the impurities, leading to results similar to those from a pure sample.

Rotating bouncing disks, tossing pizza dough, and the behavior of ultrasonic motors

NASA Astrophysics Data System (ADS)

Liu, Kuang-Chen; Friend, James; Yeo, Leslie

2009-10-01

Pizza tossing and certain forms of standing-wave ultrasonic motors (SWUMs) share a similar process for converting reciprocating input into continuous rotary motion. We show that the key features of this motion conversion process such as collision, separation and friction coupling are captured by the dynamics of a disk bouncing on a vibrating platform. The model shows that the linear or helical hand motions commonly used by pizza chefs and dough-toss performers for single tosses maximize energy efficiency and the dough’s airborne rotational speed; on the other hand, the semielliptical hand motions used for multiple tosses make it easier to maintain dough rotation at the maximum speed. The system’s bifurcation diagram and basins of attraction also provide a physical basis for understanding the peculiar behavior of SWUMs and provide a means to design them. The model is able to explain the apparently chaotic oscillations that occur in SWUMs and predict the observed trends in steady-state speed and stall torque as preload is increased.

Rotating bouncing disks, tossing pizza dough, and the behavior of ultrasonic motors.

PubMed

Liu, Kuang-Chen; Friend, James; Yeo, Leslie

2009-10-01

Pizza tossing and certain forms of standing-wave ultrasonic motors (SWUMs) share a similar process for converting reciprocating input into continuous rotary motion. We show that the key features of this motion conversion process such as collision, separation and friction coupling are captured by the dynamics of a disk bouncing on a vibrating platform. The model shows that the linear or helical hand motions commonly used by pizza chefs and dough-toss performers for single tosses maximize energy efficiency and the dough's airborne rotational speed; on the other hand, the semielliptical hand motions used for multiple tosses make it easier to maintain dough rotation at the maximum speed. The system's bifurcation diagram and basins of attraction also provide a physical basis for understanding the peculiar behavior of SWUMs and provide a means to design them. The model is able to explain the apparently chaotic oscillations that occur in SWUMs and predict the observed trends in steady-state speed and stall torque as preload is increased.

ITG-TEM turbulence simulation with bounce-averaged kinetic electrons in tokamak geometry

NASA Astrophysics Data System (ADS)

Kwon, Jae-Min; Qi, Lei; Yi, S.; Hahm, T. S.

2017-06-01

We develop a novel numerical scheme to simulate electrostatic turbulence with kinetic electron responses in magnetically confined toroidal plasmas. Focusing on ion gyro-radius scale turbulences with slower frequencies than the time scales for electron parallel motions, we employ and adapt the bounce-averaged kinetic equation to model trapped electrons for nonlinear turbulence simulation with Coulomb collisions. Ions are modeled by employing the gyrokinetic equation. The newly developed scheme is implemented on a global δf particle in cell code gKPSP. By performing linear and nonlinear simulations, it is demonstrated that the new scheme can reproduce key physical properties of Ion Temperature Gradient (ITG) and Trapped Electron Mode (TEM) instabilities, and resulting turbulent transport. The overall computational cost of kinetic electrons using this novel scheme is limited to 200%-300% of the cost for simulations with adiabatic electrons. Therefore the new scheme allows us to perform kinetic simulations with trapped electrons very efficiently in magnetized plasmas.

Neutrino Emissions in All Flavors up to the Pre-bounce of Massive Stars and the Possibility of Their Detections

NASA Astrophysics Data System (ADS)

Kato, Chinami; Nagakura, Hiroki; Furusawa, Shun; Takahashi, Koh; Umeda, Hideyuki; Yoshida, Takashi; Ishidoshiro, Koji; Yamada, Shoichi

2017-10-01

This paper is a sequel to our 2015 paper, Kato et al., which calculated the luminosities and spectra of electron-type anti-neutrinos ({\\bar{ν }}e) from the progenitors of core-collapse supernovae. Expecting that the capability to detect electron-type neutrinos ({ν }e) will increase dramatically with the emergence of liquid-argon detectors such as DUNE, we broaden the scope in this study to include all flavors of neutrinos emitted from the pre-bounce phase. We pick up three progenitor models of electron capture supernovae (ECSNe) and iron-core collapse supernovae (FeCCSNe). We find that the number luminosities reach ˜1057 s-1 and ˜1053 s-1 at maximum for {ν }e and {\\bar{ν }}e, respectively. We also estimate the numbers of detection events at terrestrial neutrino detectors including DUNE, taking flavor oscillations into account and assuming the distance to the progenitors to be 200 pc. It is demonstrated that {\\bar{ν }}e from the ECSN progenitor will be undetected at almost all detectors, whereas we will be able to observe ≳15,900 {ν }e at DUNE for the inverted mass hierarchy. From the FeCCSN progenitors, the number of {\\bar{ν }}e events will be largest for JUNO, 200-900 {\\bar{ν }}e, depending on the mass hierarchy, whereas the number of {ν }e events at DUNE is ≳ 2100 for the inverted mass hierarchy. These results imply that the detection of {\\bar{ν }}e is useful to distinguish progenitors of FeCCSNe from those of ECSNe, while {ν }e will provide us with detailed information on the collapse phase regardless of the type and mass of the progenitor.

15 ps quasi-continuously pumped passively mode-locked highly doped Nd:YAG laser in bounce geometry

NASA Astrophysics Data System (ADS)

Jelínek, M., Jr.; Kubeček, V.

2011-09-01

A semiconductor saturable absorber mirror mode-locking of a quasi-continuously pumped laser based on 2.4 at.% Nd:YAG slab in a bounce geometry was demonstrated and investigated. Output mode-locked and Q-switched train containing 15 pulses with total energy of 500 μJ was generated directly from the oscillator. The measured 15 ps pulse duration and excellent temporal stability ±2 ps are the best values for pure passively mode-locked and Q-switched Nd:YAG laser with the pulse pumping. Furthermore, using the cavity dumping technique, single 19 ps pulse with energy of 25 μJ was extracted directly from the oscillator.

Insights into Facebook Pages: an early adolescent health research study page targeted at parents.

PubMed

Amon, Krestina L; Paxton, Karen; Klineberg, Emily; Riley, Lisa; Hawke, Catherine; Steinbeck, Katharine

2016-02-01

Facebook has been used in health research, but there is a lack of literature regarding how Facebook may be used to recruit younger adolescents. A Facebook Page was created for an adolescent cohort study on the effects of puberty hormones on well-being and behaviour in early adolescence. Used as a communication tool with existing participants, it also aimed to alert potential participants to the study. The purpose of this paper is to provide a detailed description of the development of the study Facebook Page and present the fan response to the types of posts made on the Page using the Facebook-generated Insights data. Two types of posts were made on the study Facebook Page. The first type was study-related update posts and events. The second was relevant adolescent and family research and current news posts. Observations on the use of and response to the Page were made over 1 year across three phases (phase 1, very low Facebook use; phase 2, high Facebook use; phase 3, low Facebook use). Most Page fans were female (88.6%), with the largest group of fans aged between 35 and 44 years. Study-related update posts with photographs were the most popular. This paper provides a model on which other researchers could base Facebook communication and potential recruitment in the absence of established guidelines.

Infectious Diseases Team for the Early Management of Severe Sepsis and Septic Shock in the Emergency Department.

PubMed

Viale, Pierluigi; Tedeschi, Sara; Scudeller, Luigia; Attard, Luciano; Badia, Lorenzo; Bartoletti, Michele; Cascavilla, Alessandra; Cristini, Francesco; Dentale, Nicola; Fasulo, Giovanni; Legnani, Giorgio; Trapani, Filippo; Tumietto, Fabio; Verucchi, Gabriella; Virgili, Giulio; Berlingeri, Andrea; Ambretti, Simone; De Molo, Chiara; Brizi, Mara; Cavazza, Mario; Giannella, Maddalena

2017-10-15

The impact on patient survival of an infectious disease (ID) team dedicated to the early management of severe sepsis/septic shock (SS/SS) in Emergency Department (ED) has yet to be assessed. A quasiexperimental pre-post study was performed at the general ED of our hospital. During the pre phase (June 2013-July 2014), all consecutive adult patients with SS/SS were managed according to the standard of care, data were prospectively collected. During the post phase (August 2014-October 2015), patients were managed in collaboration with a dedicated ID team performing a bedside patient evaluation within 1 hour of ED arrival. Overall, 382 patients were included, 195 in the pre phase and 187 in the post phase. Median age was 82 years (interquartile range, 70-88). The most common infection sources were lung (43%) and urinary tract (17%); in 22% of cases, infection source remained unknown. During the post phase, overall compliance with the Surviving Sepsis Campaign (SSC) bundle and appropriateness of initial antibiotic therapy improved from 4.6% to 32% (P < .001) and from 30% to 79% (P < .001), respectively. Multivariate analysis showed that predictors of all-cause 14-day mortality were quick sepsis-related organ failure assessment ≥2 (hazard ratio [HR], 1.68; 95% confidence interval [CI], 1.15-2.45; P = .007), serum lactate ≥2 mmol/L (HR, 2.13; 95% CI, 1.39-3.25; P < .001), and unknown infection source (HR, 2.07; 95% CI, 1.42-3.02; P < .001); being attended during the post phase was a protective factor (HR, 0.64; 95% CI, 0.43-0.94; P = .026). Implementation of an ID team for the early management of SS/SS in the ED improved the adherence to SSC recommendations and patient survival. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Managing the Pre- and Post-analytical Phases of the Total Testing Process

PubMed Central

2012-01-01

For many years, the clinical laboratory's focus on analytical quality has resulted in an error rate of 4-5 sigma, which surpasses most other areas in healthcare. However, greater appreciation of the prevalence of errors in the pre- and post-analytical phases and their potential for patient harm has led to increasing requirements for laboratories to take greater responsibility for activities outside their immediate control. Accreditation bodies such as the Joint Commission International (JCI) and the College of American Pathologists (CAP) now require clear and effective procedures for patient/sample identification and communication of critical results. There are a variety of free on-line resources available to aid in managing the extra-analytical phase and the recent publication of quality indicators and proposed performance levels by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) working group on laboratory errors and patient safety provides particularly useful benchmarking data. Managing the extra-laboratory phase of the total testing cycle is the next challenge for laboratory medicine. By building on its existing quality management expertise, quantitative scientific background and familiarity with information technology, the clinical laboratory is well suited to play a greater role in reducing errors and improving patient safety outside the confines of the laboratory. PMID:22259773

The COSAS survey I: First results from the IRAM mapping survey of 12CO J=1-0 & J=2-1 emission in AGB and early post-AGB circumstellar envelopes

NASA Astrophysics Data System (ADS)

Alcolea Jimanez, J.; Castr-Carrizo, A.; Quintana-Lacaci, G.; Neri, R.; Bujarrabal, V.; Schoeier, F. L.; Winters, J. M.; Olofsson, H.; Lindqvist, M.; Lucas, R.; Grewing, M.

Here we present the first result from the COSAS (CO Survey of late AGB Stars) program (P.I. A. Castro-Carrizo), a J=1-0 and J=2-1 line emission mapping survey of a statistically representative sample of circumstellar envelopes around AGB and post-AGB stars. This mapping survey has been carried out to investigate the small and large scale morphological and kinematical properties of the molecular environment surrounding stars in the late AGB and early post-AGB phases. For this, COSAS ideally combines the high spatial resolution and sensitivity of the IRAM Plateau de Bure Interferometer, with the IRAM Pico de Veleta 30m-MRT capabilities to map more extended emission. The whole program includes of 45 stars, selected to sample a wide variety in mass loss rate, chemical type (M, S and C types), variability type (regular variables like Miras and OH/IRs, semiregulars, irregulars, and non varying post-AGBs), evolutionary state, and initial mass. By no means it is an unbiased sample, so results must be interpreted with care, and in terms of the different population of sources represented in the sample. COSAS products (at first. maps and velocity fields, and after modeling, excitation and density profiles across the envelopes) provides means to quantify variations in the mass-loss rate history, assess on the prevalence of different morphological and kinematical features, and investigate the appearance of fast aspherical winds in the late-AGB and early post-AGB phases. This paper, which is the first of a series of COSAS papers, presents the results from the final mapping of a sample of 16 selected sources (about 1/3 of the whole list), namely: WX Psc, IK Tau, TX Cam, RX Boo, X Her, CRL 2362, x Cyg, V Cyg, S Cep, OH 104.9+2.4, R Cas, IRAS 19475+3119, IRAS 20028+3910, IRAS 21282+5050, IRAS 23321+6545 and CRL 2477. The envelopes around late AGB stars are found to be mostly spherical, but often presenting features like concentric arcs (R Cas and TX Cam), spiral density patterns

Three steps to writing adaptive study protocols in the early phase clinical development of new medicines

PubMed Central

2014-01-01

This article attempts to define terminology and to describe a process for writing adaptive, early phase study protocols which are transparent, self-intuitive and uniform. It provides a step by step guide, giving templates from projects which received regulatory authorisation and were successfully performed in the UK. During adaptive studies evolving data is used to modify the trial design and conduct within the protocol-defined remit. Adaptations within that remit are documented using non-substantial protocol amendments which do not require regulatory or ethical review. This concept is efficient in gathering relevant data in exploratory early phase studies, ethical and time- and cost-effective. PMID:24980283

Cosmological QCD phase transition in steady non-equilibrium dissipative Hořava–Lifshitz early universe

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khodadi, M., E-mail: M.Khodadi@sbu.ac.ir; Sepangi, H.R., E-mail: hr-sepangi@sbu.ac.ir

We study the phase transition from quark–gluon plasma to hadrons in the early universe in the context of non-equilibrium thermodynamics. According to the standard model of cosmology, a phase transition associated with chiral symmetry breaking after the electro-weak transition has occurred when the universe was about 1–10 μs old. We focus attention on such a phase transition in the presence of a viscous relativistic cosmological background fluid in the framework of non-detailed balance Hořava–Lifshitz cosmology within an effective model of QCD. We consider a flat Friedmann–Robertson–Walker universe filled with a non-causal and a causal bulk viscous cosmological fluid respectively and investigatemore » the effects of the running coupling constants of Hořava–Lifshitz gravity, λ, on the evolution of the physical quantities relevant to a description of the early universe, namely, the temperature T, scale factor a, deceleration parameter q and dimensionless ratio of the bulk viscosity coefficient to entropy density (ξ)/s . We assume that the bulk viscosity cosmological background fluid obeys the evolution equation of the steady truncated (Eckart) and full version of the Israel–Stewart fluid, respectively. -- Highlights: •In this paper we have studied quark–hadron phase transition in the early universe in the context of the Hořava–Lifshitz model. •We use a flat FRW universe with the bulk viscosity cosmological background fluid obeying the evolution equation of the steady truncated (Eckart) and full version of the Israel–Stewart fluid, respectively.« less

Mechanical Analog of the Synchrotron, Illustrating Phase Stability and Two-Dimensional Focusing

ERIC Educational Resources Information Center

Alvarez, Luis W.; And Others

1975-01-01

Describes a model in which a steel ball bounces in synchronism with a vertically oscillating piston. The period of oscillation can be varied over a 3:1 range with the amplitude kept constant. As the period is increased, the ball bounces higher, contrary to the intuition of most observers. (Author/GS)

A class of simple bouncing and late-time accelerating cosmologies in f(R) gravity

NASA Astrophysics Data System (ADS)

Kuiroukidis, A.

We consider the field equations for a flat FRW cosmological model, given by Eq. (??), in an a priori generic f(R) gravity model and cast them into a, completely normalized and dimensionless, system of ODEs for the scale factor and the function f(R), with respect to the scalar curvature R. It is shown that under reasonable assumptions, namely for power-law functional form for the f(R) gravity model, one can produce simple analytical and numerical solutions describing bouncing cosmological models where in addition there are late-time accelerating. The power-law form for the f(R) gravity model is typically considered in the literature as the most concrete, reasonable, practical and viable assumption [see S. D. Odintsov and V. K. Oikonomou, Phys. Rev. D 90 (2014) 124083, arXiv:1410.8183 [gr-qc

Endothelial gaps and adherent leukocytes in allergen-induced early- and late-phase plasma leakage in rat airways.

PubMed Central

Baluk, P.; Bolton, P.; Hirata, A.; Thurston, G.; McDonald, D. M.

1998-01-01

Exposure of sensitized individuals to antigen can induce allergic responses in the respiratory tract, manifested by early and late phases of vasodilatation, plasma leakage, leukocyte influx, and bronchoconstriction. Similar responses can occur in the skin, eye, and gastrointestinal tract. The early-phase response involves mast cell mediators and the late-phase response is leukocyte dependent, but the mechanism of leakage is not understood. We sought to identify the leaky blood vessels, to determine whether these vessels contained endothelial gaps, and to analyze the relationship of the gaps to adherent leukocytes, using biotinylated lectins or silver nitrate to stain the cells in situ and Monastral blue as a tracer to quantify plasma leakage. Most of the leakage occurred in postcapillary venules (< 40-microns diameter), whereas most of the leukocyte migration (predominantly neutrophils) occurred in collecting venules. Capillaries and arterioles did not leak. Endothelial gaps were found in the leaky venules, both by silver nitrate staining and by scanning electron microscopy, and 94% of the gaps were distinct from sites of leukocyte adhesion or migration. We conclude that endothelial gaps contribute to both early and late phases of plasma leakage induced by antigen, but most leakage occurs upstream to sites of leukocyte adhesion. Images Figure 3 Figure 5 Figure 6 Figure 7 PMID:9626051

Nonsingular cosmology with a scale-invariant spectrum of cosmological perturbations from Lee-Wick theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cai Yifu; Qiu Taotao; Brandenberger, Robert

2009-07-15

We study the cosmology of a Lee-Wick type scalar field theory. First, we consider homogeneous and isotropic background solutions and find that they are nonsingular, leading to cosmological bounces. Next, we analyze the spectrum of cosmological perturbations which result from this model. Unless either the potential of the Lee-Wick theory or the initial conditions are finely tuned, it is impossible to obtain background solutions which have a sufficiently long period of inflation after the bounce. More interestingly, however, we find that in the generic noninflationary bouncing cosmology, perturbations created from quantum vacuum fluctuations in the contracting phase have the correctmore » form to lead to a scale-invariant spectrum of metric inhomogeneities in the expanding phase. Since the background is nonsingular, the evolution of the fluctuations is defined unambiguously through the bounce. We also analyze the evolution of fluctuations which emerge from thermal initial conditions in the contracting phase. The spectrum of gravitational waves stemming from quantum vacuum fluctuations in the contracting phase is also scale-invariant, and the tensor to scalar ratio is not suppressed.« less

Nanodroplet impact onto solid platinum surface: Spreading and bouncing

NASA Astrophysics Data System (ADS)

Lussier, Daniel; Ventikos, Yiannis

2009-11-01

The impact of droplets onto solid surfaces is found in a huge variety of natural and technological applications, from rain drops splashing on the pavement, to material manufacturing by molten droplet deposition. Taking inspiration from existing microfluidic technologies (i.e. lab-on-chip), there is increasing interest in the use of nanodroplets (D < 100 nm) for a number of applications such as drug delivery and semiconductor device manufacturing. However, as the size of the droplet is reduced into the nanoscale, the direct use of previously obtained macroscopic results is not guaranteed. At the nanoscale, important effects due to the molecular nature of the fluid, thermal fluctuations and reduced dimensionality can play a critical role in determining system dynamics. In this paper we present the results of large-scale, fully atomistic, three-dimensional molecular dynamics (MD) simulation of an argon nanodroplet (D = 18 nm, 54 000 atoms) impact onto a solid platinum surface, using the LAMMPS software package. The fluid argon is modeled using the well-known Lennard-Jones (LJ) potential, while the embedded-atom model (EAM) potential is used for the solid platinum. By varying both the impact velocities (10-1000 m/s) and the wettability of the solid surface a wide range of impact behaviors is observed, from smooth spreading, to bouncing recoil, pointing towards a wide array of potential applications.

Contribution of economic evaluation to decision making in early phases of product development: a methodological and empirical review.

PubMed

Hartz, Susanne; John, Jürgen

2008-01-01

Economic evaluation as an integral part of health technology assessment is today mostly applied to established technologies. Evaluating healthcare innovations in their early states of development has recently attracted attention. Although it offers several benefits, it also holds methodological challenges. The aim of our study was to investigate the possible contributions of economic evaluation to industry's decision making early in product development and to confront the results with the actual use of early data in economic assessments. We conducted a literature research to detect methodological contributions as well as economic evaluations that used data from early phases of product development. Economic analysis can be beneficially used in early phases of product development for various purposes including early market assessment, R&D portfolio management, and first estimations of pricing and reimbursement scenarios. Analytical tools available for these purposes have been identified. Numerous empirical works were detected, but most do not disclose any concrete decision context and could not be directly matched with the suggested applications. Industry can benefit from starting economic evaluation early in product development in several ways. Empirical evidence suggests that there is still potential left unused.

Hemoglobin phase of oxygenation and deoxygenation in early brain development measured using fNIRS

PubMed Central

Watanabe, Hama; Shitara, Yoshihiko; Aoki, Yoshinori; Inoue, Takanobu; Tsuchida, Shinya; Takahashi, Naoto; Taga, Gentaro

2017-01-01

A crucial issue in neonatal medicine is the impact of preterm birth on the developmental trajectory of the brain. Although a growing number of studies have shown alterations in the structure and function of the brain in preterm-born infants, we propose a method to detect subtle differences in neurovascular and metabolic functions in neonates and infants. Functional near-infrared spectroscopy (fNIRS) was used to obtain time-averaged phase differences between spontaneous low-frequency (less than 0.1 Hz) oscillatory changes in oxygenated hemoglobin (oxy-Hb) and those in deoxygenated hemoglobin (deoxy-Hb). This phase difference was referred to as hemoglobin phase of oxygenation and deoxygenation (hPod) in the cerebral tissue of sleeping neonates and infants. We examined hPod in term, late preterm, and early preterm infants with no evidence of clinical issues and found that all groups of infants showed developmental changes in the values of hPod from an in-phase to an antiphase pattern. Comparison of hPod among the groups revealed that developmental changes in hPod in early preterm infants precede those in late preterm and term infants at term equivalent age but then, progress at a slower pace. This study suggests that hPod measured using fNIRS is sensitive to the developmental stage of the integration of circular, neurovascular, and metabolic functions in the brains of neonates and infants. PMID:28196885

Early post-metamorphic, Carboniferous blastoid reveals the evolution and development of the digestive system in echinoderms.

PubMed

Rahman, Imran A; Waters, Johnny A; Sumrall, Colin D; Astolfo, Alberto

2015-10-01

Inferring the development of the earliest echinoderms is critical to uncovering the evolutionary assembly of the phylum-level body plan but has long proven problematic because early ontogenetic stages are rarely preserved as fossils. Here, we use synchrotron tomography to describe a new early post-metamorphic blastoid echinoderm from the Carboniferous (approx. 323 Ma) of China. The resulting three-dimensional reconstruction reveals a U-shaped tubular structure in the fossil interior, which is interpreted as the digestive tract. Comparisons with the developing gut of modern crinoids demonstrate that crinoids are an imperfect analogue for many extinct groups. Furthermore, consideration of our findings in a phylogenetic context allows us to reconstruct the evolution and development of the digestive system in echinoderms more broadly; there was a transition from a straight to a simple curved gut early in the phylum's evolution, but additional loops and coils of the digestive tract (as seen in crinoids) were not acquired until much later. © 2015 The Author(s).

A chronicle of BScN honours/ non-honours outcomes and experiences post-graduation.

PubMed

Gillis, Angela

2007-01-01

This paper reports on a graduate follow-up of the outcomes of participation in an honours BScN program, two to seven years post-graduation. It compares two groups of graduates with high GPA scores, both initially eligible to complete the honours program. One group completed the honours program; the other group completed the regular BScN program. In phase 1 of the study, a self-administered mailed questionnaire was sent to participants to assess their involvement in research activities, occupancy of leadership positions, enrollment in graduate studies and demonstration of liberal education competencies in their professional lives after graduation. In phase two, personal interviews were held with a purposive subsample of participants to explore early career workplace experiences with research-based activities and participants' perceptions of factors influencing their decision to complete or not to complete the honours program. Graduates with high GPA scores from both programs demonstrated expected professional outcomes post-graduation. Follow up at 10-12 years post-graduation and replication with larger samples are recommended.

[Early versus delayed physiotherapy in the treatment of post-prostatectomy male urinary incontinence].

PubMed

Tarcía Kahihara, Carina; Ferreira, Ubirajora; Nardi Pedro, Renato; Matheus, Wagner Eduardo; Rodrigues Netto, Nelson

2006-10-01

To analyze the importance of the starting time for pelvic floor physiotherapy in patients with post radical prostatectomy urinary incontinence. Between May 2003 and February 2004 18 patients with the diagnosis of post radical prostatectomy urinary incontinence underwent physiotherapy of the pelvic floor. Each patient received 12 sessions using kinesotherapy and electric stimulation on a weekly basis. Patients were divided into two groups: Group 1 included eight patients that started therapy within the first six months after surgery; Group 2 included 10 patients starting therapy after the sixth post operative month. All patients were evaluated by the pad test and number of incontinence pads per day. Evaluating pad tests before and after treatment, six patients in group 1 had a reduction of the amount of urine leak in comparison to seven patients in group 2. The statistical analysis showed significant differences before and after treatment for both groups (group 1: p = 0.028; group 2: p = 0.018). The evaluation of the number of pads showed: Group 1: all eight patients using pods had a reduction in the number of pads. Group 2: 5 of the eight patients using pads had a reduction and the other three continued using the same number. Statistical analysis comparing the number of pads per day before and after treatment showed a significant difference in group 1 (p = 0.004). There was no statistically significant difference in the number of pads per day before and after physiotherapy in group 2, although half of the patients showed a diminishment in the number of pads required after treatment. Results demonstrate that early indication of physiotherapy for the treatment of post radical prostatectomy urinary incontinence is better than delayed treatment. New works may be developed in the future to confirm our results.

Inside information: Financial conflicts of interest for research subjects in early phase clinical trials.

PubMed

Helft, Paul R; Ratain, Mark J; Epstein, Richard A; Siegler, Mark

2004-05-05

In recent years, several research subjects have told us that they had bought or intended to buy stock in the companies sponsoring the clinical trials in which they were enrolled. This situation has led us to ask what, if any, are physician-investigators' scientific, ethical, and legal responsibilities concerning research subjects who choose to buy stock in the companies sponsoring the clinical trials in which they are participating. Although the scope of this problem is unknown and is likely to be small, this commentary examines the scientific, ethical, and legal concerns raised by such activities on the part of research subjects enrolled in early phase clinical trials. In addition, this commentary also outlines the basis for our opinion that research subjects involved in an early phase clinical trial should avoid the financial conflicts of interest created by trading stock in the company sponsoring the clinical trial.

Post-resuscitation care following out-of-hospital and in-hospital cardiac arrest

PubMed Central

Girotra, Saket; Chan, Paul S; Bradley, Steven M

2016-01-01

Cardiac arrest is a leading cause of death in developed countries. Although a majority of cardiac arrest patients die during the acute event, a substantial proportion of cardiac arrest deaths occur in patients following successful resuscitation and can be attributed to the development of post-cardiac arrest syndrome. There is growing recognition that integrated post-resuscitation care, which encompasses targeted temperature management (TTM), early coronary angiography and comprehensive critical care, can improve patient outcomes. TTM has been shown to improve survival and neurological outcome in patients who remain comatose especially following out-of-hospital cardiac arrest due to ventricular arrhythmias. Early coronary angiography and revascularisation if needed may also be beneficial during the post-resuscitation phase, based on data from observational studies. In addition, resuscitated patients usually require intensive care, which includes mechanical ventilator, haemodynamic support and close monitoring of blood gases, glucose, electrolytes, seizures and other disease-specific intervention. Efforts should be taken to avoid premature withdrawal of life-supporting treatment, especially in patients treated with TTM. Given that resources and personnel needed to provide high-quality post-resuscitation care may not exist at all hospitals, professional societies have recommended regionalisation of post-resuscitation care in specialised ‘cardiac arrest centres’ as a strategy to improve cardiac arrest outcomes. Finally, evidence for post-resuscitation care following in-hospital cardiac arrest is largely extrapolated from studies in patients with out-of-hospital cardiac arrest. Future studies need to examine the effectiveness of different post-resuscitation strategies, such as TTM, in patients with in-hospital cardiac arrest. PMID:26385451

Divided attention can enhance early-phase memory encoding: the attentional boost effect and study trial duration.

PubMed

Mulligan, Neil W; Spataro, Pietro

2015-07-01

Divided attention during encoding typically produces marked reductions in later memory. The attentional boost effect (ABE) is a surprising variation on this phenomenon. In this paradigm, each study stimulus (e.g., a word) is presented along with a target or a distractor (e.g., different colored circles) in a detection task. Later memory is better for stimuli co-occurring with targets. The present experiments indicate that the ABE arises during an early phase of memory encoding that involves initial stimulus perception and comprehension rather than at a later phase entailing controlled, elaborative rehearsal. Experiment 1 demonstrated that the ABE was robust at a short study duration (700 ms) and did not increase with increasing study trial durations (1,500 ms and 4,000 ms). Furthermore, the target condition is boosted to the level of memory performance in a full-attention condition for the short duration but not the long duration. Both results followed from the early-phase account. This account also predicts that for very short study times (limiting the influence of late-phase controlled encoding and thus minimizing the usual negative effect of divided attention), the target condition will produce better memory than will the full-attention condition. Experiment 2 used a study time of 400 ms and found that words presented with targets lead to greater recognition accuracy than do either words presented with distractors or words in the full-attention condition. Consistent with the early-phase account, a divided attention condition actually produced superior memory than did the full-attention condition, a very unusual but theoretically predicted result. (c) 2015 APA, all rights reserved.

Gravitational waves and Higgs boson couplings for exploring first order phase transition in the model with a singlet scalar field

NASA Astrophysics Data System (ADS)

Hashino, Katsuya; Kakizaki, Mitsuru; Kanemura, Shinya; Ko, Pyungwon; Matsui, Toshinori

2017-03-01

We calculate the spectrum of gravitational waves originated from strongly first order electroweak phase transition in the extended Higgs model with a real singlet scalar field. In order to calculate the bubble nucleation rate, we perform a two-field analysis and evaluate bounce solutions connecting the true and the false vacua using the one-loop effective potential at finite temperatures. Imposing the Sakharov condition of the departure from thermal equilibrium for baryogenesis, we survey allowed regions of parameters of the model. We then investigate the gravitational waves produced at electroweak bubble collisions in the early Universe, such as the sound wave, the bubble wall collision and the plasma turbulence. We find that the strength at the peak frequency can be large enough to be detected at future space-based gravitational interferometers such as eLISA, DECIGO and BBO. Predicted deviations in the various Higgs boson couplings are also evaluated at the zero temperature, and are shown to be large enough too. Therefore, in this model strongly first order electroweak phase transition can be tested by the combination of the precision study of various Higgs boson couplings at the LHC, the measurement of the triple Higgs boson coupling at future lepton colliders and the shape of the spectrum of gravitational wave detectable at future gravitational interferometers.

Early Childhood Settings in 15 Countries: What Are Their Structural Characteristics? The IEA Preprimary Project, Phase 2.

ERIC Educational Resources Information Center

Olmsted, Patricia P., Ed.; Montie, Jeanne, Ed.

This is the second of four monographs reporting the findings of Phase 2 of the International Association for the Evaluation of Educational Achievement (IEA) Preprimary Project, which presents data on the physical characteristics of children's early childhood settings. Early childhood settings were documented in the following 15 countries: (1)…

Discrete effect on the halfway bounce-back boundary condition of multiple-relaxation-time lattice Boltzmann model for convection-diffusion equations.

PubMed

Cui, Shuqi; Hong, Ning; Shi, Baochang; Chai, Zhenhua

2016-04-01

In this paper, we will focus on the multiple-relaxation-time (MRT) lattice Boltzmann model for two-dimensional convection-diffusion equations (CDEs), and analyze the discrete effect on the halfway bounce-back (HBB) boundary condition (or sometimes called bounce-back boundary condition) of the MRT model where three different discrete velocity models are considered. We first present a theoretical analysis on the discrete effect of the HBB boundary condition for the simple problems with a parabolic distribution in the x or y direction, and a numerical slip proportional to the second-order of lattice spacing is observed at the boundary, which means that the MRT model has a second-order convergence rate in space. The theoretical analysis also shows that the numerical slip can be eliminated in the MRT model through tuning the free relaxation parameter corresponding to the second-order moment, while it cannot be removed in the single-relaxation-time model or the Bhatnagar-Gross-Krook model unless the relaxation parameter related to the diffusion coefficient is set to be a special value. We then perform some simulations to confirm our theoretical results, and find that the numerical results are consistent with our theoretical analysis. Finally, we would also like to point out the present analysis can be extended to other boundary conditions of lattice Boltzmann models for CDEs.

Efficient runner safety assessment during early design phase and root cause analysis

NASA Astrophysics Data System (ADS)

Liang, Q. W.; Lais, S.; Gentner, C.; Braun, O.

2012-11-01

Fatigue related problems in Francis turbines, especially high head Francis turbines, have been published several times in the last years. During operation the runner is exposed to various steady and unsteady hydraulic loads. Therefore the analysis of forced response of the runner structure requires a combined approach of fluid dynamics and structural dynamics. Due to the high complexity of the phenomena and due to the limitation of computer power, the numerical prediction was in the past too expensive and not feasible for the use as standard design tool. However, due to continuous improvement of the knowledge and the simulation tools such complex analysis has become part of the design procedure in ANDRITZ HYDRO. This article describes the application of most advanced analysis techniques in runner safety check (RSC), including steady state CFD analysis, transient CFD analysis considering rotor stator interaction (RSI), static FE analysis and modal analysis in water considering the added mass effect, in the early design phase. This procedure allows a very efficient interaction between the hydraulic designer and the mechanical designer during the design phase, such that a risk of failure can be detected and avoided in an early design stage.The RSC procedure can also be applied to a root cause analysis (RCA) both to find out the cause of failure and to quickly define a technical solution to meet the safety criteria. An efficient application to a RCA of cracks in a Francis runner is quoted in this article as an example. The results of the RCA are presented together with an efficient and inexpensive solution whose effectiveness could be proven again by applying the described RSC technics. It is shown that, with the RSC procedure developed and applied as standard procedure in ANDRITZ HYDRO such a failure is excluded in an early design phase. Moreover, the RSC procedure is compatible with different commercial and open source codes and can be easily adapted to apply for

Risk-adjusted outcome prediction with initial post-cardiac arrest illness severity: implications for cardiac arrest survivors being considered for early invasive strategy.

PubMed

Reynolds, Joshua C; Rittenberger, Jon C; Toma, Catalin; Callaway, Clifton W

2014-09-01

Early CATH is recommended for cardiac arrest survivors with STEMI or suspicion for coronary ischemia. Comatose patients are at risk of death from neurologic injury irrespective of CATH, but post-procedural mortality data do not distinguish between causes of death. Pittsburgh Post Cardiac Arrest Category (PCAC) is a validated, early post-cardiac arrest illness severity score based on initial cardiopulmonary dysfunction and neurologic examination. We evaluated the association between early coronary angiography (CATH) and patient outcome after adjusting for initial post-cardiac arrest illness severity. Retrospective study of a prospective cardiac arrest database at a single site. We included 1011 adult survivors of non-traumatic in-hospital or out-of-hospital cardiac arrest from 2005 to 2012, then stratified by PCAC and immediate CATH. Logistic regression tested the association between immediate CATH and patient outcomes, adjusting for PCAC. Overall, 273 (27%) received immediate CATH. Patients with immediate CATH had higher proportions of good outcome in all but the most severe stratum of illness severity (11% vs. 6%; p=0.11). The primary mode of death was neurologic for all but the least severe stratum. Adjusting for PCAC, immediate CATH was associated with favorable discharge disposition (OR 1.92; 95%CI 1.20, 3.07; p=0.006) and modified Rankin scale (OR 1.95; 95%CI 1.12, 3.38; p=0.02). The benefit of CATH is less clear in the most severe stratum of illness, in which the high risk of mortality is primarily from neurologic causes. PCAC is a risk-stratification tool that provides pre-procedural risk-adjusted outcome prediction for post-cardiac arrest patients being evaluated for immediate CATH. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Sleep supports cued fear extinction memory consolidation independent of circadian phase.

PubMed

Melo, Irene; Ehrlich, Ingrid

2016-07-01

Sleep promotes memory, particularly for declarative learning. However, its role in non-declarative, emotional memories is less well understood. Some studies suggest that sleep may influence fear-related memories, and thus may be an important factor determining the outcome of treatments for emotional disorders such as post-traumatic stress disorder. Here, we investigated the effect of sleep deprivation and time of day on fear extinction memory consolidation. Mice were subjected to a cued Pavlovian fear and extinction paradigm at the beginning of their resting or active phase. Immediate post-extinction learning sleep deprivation for 5h compromised extinction memory when tested 24h after learning. Context-dependent extinction memory recall was completely prevented by sleep-manipulation during the resting phase, while impairment was milder during the active phase and extinction memory retained its context-specificity. Importantly, control experiments excluded confounding factors such as differences in baseline locomotion, fear generalization and stress hormone levels. Together, our findings indicate that post-learning sleep supports cued fear extinction memory consolidation in both circadian phases. The lack of correlation between memory efficacy and sleep time suggests that extinction memory may be influenced by specific sleep events in the early consolidation period. Copyright © 2016 Elsevier Inc. All rights reserved.

CHANGES IN SERUM HOMOCYSTEINE LEVEL FOLLOW TWO DIFFERENT TRENDS IN PATIENTS DURING EARLY POST MYOCARDIAL INFARCTION PERIOD

PubMed Central

Valjevac, Amina; Džubur, Alen; Nakaš-Ićindić, Emina; Hadžović-Džuvo, Almira; Zaćiragić, Asija; Lepara, Orhan; Arslanagić, Amila

2009-01-01

The evolution of homocysteine (Hcy) changes after acute myocardial infarction is still not elucidated. Serum Hcy concentration has been shown to increase between acute and convalescent period after myocardial infarction and stroke, Also a decrease in serum Hcy during acute phase was observed, It is still not clear whether the Hcy is a culprit or an innocent bystander in cardiovascular diseases, Addressing the discrepancies in Hcy changes in patients with acute myocardial infarction might give insight in Hcy role in cardiovascular diseases and offer implications both for the clinical interpretation and patients risk stratification, The aim of the study was to evaluate serum Hcy concentration changes during early post myocardial infarction, The study included 55 patients with AMI from the Clinics for Heart Diseases and Rheumatism at University of Sarajevo Clinics Centre, For Hcy analysis blood was collected on day 2 and 5 after the AMI onset, Serum Hcy concentration was determined quantitatively with fluorescent polarisation immunoassay on AxSYM system, Cluster analysis revealed two groups ofAMI patients with different trends of serum Hcy changes, Increase in serum Hcy concentration was observed in 33 (60,0%) patients (AMI 1 group), while in 22 (40,0%) patients a decrease was observed (AMI 2 group), On day 2, patients in AMI 2 group had significantly higher mean Hcy concentration compared to AMI 1 group of patients (15,27±0,96 and 11,59±0,61 μmol/L p<0,05), On day 5, no significant difference in mean Hcy level between AMI 1 and AMI 2 group of patients was observed (14,86±1,1 vs, 12,75±0,74 μmol/L respectively), Significant differences between AMI 1 and AMI 2 patients were observed in VLDLC levels and CK-MB activity on day 2, Patients in AMI 1 group had significant increase in platelets count from day 2 to day 5 (230,1±11,6 vs. 244,2±11,0; p<0,05). Our study of serial Hcy changes in patients with AMI revealed two different patterns of Hcy changes in early post

Characterization of Early-Phase Neutrophil Extracellular Traps in Urinary Tract Infections

PubMed Central

Yu, Yanbao; Kwon, Keehwan; Tsitrin, Tamara; Sikorski, Patricia; Nelson, Karen E.; Pieper, Rembert

2017-01-01

Neutrophils have an important role in the antimicrobial defense and resolution of urinary tract infections (UTIs). Our research suggests that a mechanism known as neutrophil extracellular trap (NET) formation is a defense strategy to combat pathogens that have invaded the urinary tract. A set of human urine specimens with very high neutrophil counts had microscopic evidence of cellular aggregation and lysis. Deoxyribonuclease I (DNase) treatment resulted in disaggregation of such structures, release of DNA fragments and a proteome enriched in histones and azurophilic granule effectors whose quantitative composition was similar to that of previously described in vitro-formed NETs. The effector proteins were further enriched in DNA-protein complexes isolated in native PAGE gels. Immunofluorescence microscopy revealed a flattened morphology of neutrophils associated with decondensed chromatin, remnants of granules in the cell periphery, and myeloperoxidase co-localized with extracellular DNA, features consistent with early-phase NETs. Nuclear staining revealed that a considerable fraction of bacterial cells in these structures were dead. The proteomes of two pathogens, Staphylococcus aureus and Escherichia coli, were indicative of adaptive responses to early-phase NETs, specifically the release of virulence factors and arrest of ribosomal protein synthesis. Finally, we discovered patterns of proteolysis consistent with widespread cleavage of proteins by neutrophil elastase, proteinase 3 and cathepsin G and evidence of citrullination in many nuclear proteins. PMID:28129394

Sustained attention is favored by progesterone during early luteal phase and visuo-spatial memory by estrogens during ovulatory phase in young women.

PubMed

Solís-Ortiz, S; Corsi-Cabrera, M

2008-08-01

Studies examining the influence of the menstrual cycle on cognitive function have been highly contradictory. The maintenance of attention is key to successful information processing, however how it co-vary with other cognitive functions and mood in function of phases of the menstrual cycle is not well know. Therefore, neuropsychological performance of nine healthy women with regular menstrual cycles was assessed during ovulation (OVU), early luteal (EL), late luteal (LL) and menstrual (MEN) phases. Neuropsychological test scores of sustained attention, executive functions, manual coordination, visuo-spatial memory, verbal fluency, spatial ability, anxiety and depression were obtained and submitted to a principal components analysis (PCA). Five eigenvectors that accounted the 68.31% of the total variance were identified. Performance of the sustained attention was grouped in an independent eigenvector (component 1), and the scores on verbal fluency and visuo-spatial memory were grouped together in an eigenvector (component 5), which explained 17.69% and 12.03% of the total variance, respectively. The component 1 (p<0.034) and the component 5 (p<0.003) showed significant variations during the menstrual cycle. Sustained attention showed an increase in the EL phase, when the progesterone is high. Visuo-spatial memory was increased, while that verbal fluency was decreased during the OVU phase, when the estrogens levels are high. These results indicate that sustained attention is favored by early luteal phase progesterone and do not covaried with any other neuropsychological variables studied. The influence of the estrogens on visuo-spatial memory was corroborated, and covaried inversely with verbal fluency.

Post-fire tree establishment and early cohort development in conifer forests of the western Cascades of Oregon, USA

Treesearch

Alan J. Tepley; Frederick J. Swanson; Thomas A. Spies

2014-01-01

Early-seral ecosystems make important contributions to regional biodiversity by supporting high abundance and diversity of many plant and animal species that are otherwise rare or absent from closed-canopy forests. Therefore, the period of post-fire tree establishment is a key stage in forest stand and ecosystem development that can be viewed in the context of...

Early Human Testing Initiative Phase 1 Regenerative Life Support Systems

NASA Image and Video Library

1995-08-08

Early Human Testing (EHT) Initiative Phase 1 Regenerative Life Support Systems Laboratory (RLSSL). Nigel Packham activities in the Variable Pressure Growth Chamber which he lived inside for 15 days. A crowd of well-wishers outside the test chamber, at the console are John Lewis, Ed Mohr and Marybeth Edeen (15577). Packham exiting the chamber (15578-81). Packham is the focus of television cameras and reporters (15582-3). Don Henninger interviewed by reporters (15584). Packham is presented with a jacket after his stay in the chamber (15585). Packham inside the wheat growth chamber checking the condition of the plants (15586-7, 15597). Packham exercising on a recumbant bicycle (15588, 15592). Packham, through the window into the growth chamber, displays a handful of wheat plants to console monitor Dan Barta (15589-90). Group portrait of the team conducting the Early Human Testing Initiative Phase 1 Regenerative Life Support Systems test and include, front row, from left: Jeff Dominick and Don Overton and back row, from left, unidentified member, Marybeth Edeen, Nigel Packham, John Lewis, Ed Mohr, Dan Barta and Tim Monk (15591). Harry Halford prepares to send a package through the airlock to Packham (15593). Packham displays a handful of wheat plants (15594). Packham fixes himself a bowl of cereal (15595) and retrieves a carton of milk from the refrigerator (15596). Packham retrieves a package from the airlock (15598). Packham packs up trash in plastic bag (15599-600) and sends it back through the airlock (15601). Packham gets a cup of water (15602) and heats it in the microwave (15603).

[The correlation between serum uric acid level and early-phase insulin secretion in subjects with normal glucose regulation].

PubMed

Lu, L; Zheng, F P; Li, H

2016-05-01

To investigate the correlation between serum uric acid (SUA) level and early-phase insulin secretion in subjects with normal glucose regulation (NGR). Totally 367 community NGR residents confirmed by a 75g oral glucose tolerance test were enrolled. The insulin resistance index (HOMA-IR) and the early-phase insulin secretion index after a glucose load (ΔI30/ΔG30) were used to estimate the insulin sensitivity and the early-phase insulin secretion, respectively. The subjects were divided into 4 groups according to the SUA level quartiles. Differences in early-phase insulin levels, ΔI30/ΔG30, and HOMA-IR were compared among the 4 groups. Age, BMI, waist circumference, systolic blood pressure, diastolic blood pressure, fasting insulin (FINS), 30 minutes postprandial insulin(30 minINS), 2 hours postprandial insulin(2hINS), HOMA-IR and TG levels increased across the rising categories of SUA levels, while the HDL-C was decreased across the SUA groups (P<0.01). The SUA level was positively correlated with age(r=0.157, P<0.01), BMI(r=0.262, P<0.01), waist circumference(r=0.372, P<0.01), systolic blood pressure(r=0.200, P<0.01), diastolic blood pressure(r=0.254, P<0.01), 30 minutes postprandial plasma glucose(r=0.118, P=0.023), FINS(r=0.249, P<0.01), 30minINS(r=0.189, P<0.01), 2hINS(r=0.206, P<0.01), glycosylated hemoglobin(HbA1c, r=0.106, P=0.042), HOMA-IR(r=0.244, P<0.01), TG(r=0.350, P<0.01), ΔI30/ΔG30(r=0.144, P<0.01), and negatively correlated with HDL-C level(r=-0.321, P<0.01). Multiple stepwise regression analysis showed that SUA(β=0.292, P<0.01) and HOMA-IR(β=29.821, P<0.01) were positively associated with ΔI30/ΔG30. SUA level is closely related with the early-phase insulin secretion in NGR subjects.

Prostate-specific antigen (PSA) bounce and other fluctuations: which biochemical relapse definition is least prone to PSA false calls? An analysis of 2030 men treated for prostate cancer with external beam or brachytherapy with or without adjuvant androgen deprivation therapy.

PubMed

Pickles, Tom

2006-04-01

To determine the false call (FC) rate for prostate-specific antigen (PSA) relapse according to nine different PSA relapse definitions after a PSA fluctuation (bounce) has occurred after external beam radiation therapy (EBRT) or brachytherapy, with or without adjuvant androgen deprivation therapy. An analysis of a prospective database of 2030 patients was conducted. Prostate-specific antigen relapse was scored according to the American Society for Therapeutic Radiology and Oncology (ASTRO), Vancouver, threshold + n, and nadir + n definitions for the complete data set and then compared against a truncated data set, with data subsequent to the height of the bounce deleted. The FC rate was calculated for each definition. The bounce rate, with this very liberal definition of bounce, was 58% with EBRT and 84% with brachytherapy. The FC rate was lowest with nadir + 2 and + 3 definitions (2.2% and 1.6%, respectively) and greatest with low-threshold and ASTRO definitions (32% and 18%, respectively). The ASTRO definition was particularly susceptible to FC when androgen deprivation therapy was used with radiation (24%). New definitions of biochemical non-evidence of disease that are more robust than the ASTRO definition have been identified. Those with the least FC rates are the nadir + 2 and nadir + 3 definitions, both of which are being considered to replace the ASTRO definition by the 2005 meeting of the Radiation Therapy Oncology Group-ASTRO consensus panel.

77 FR 36958 - Proposed Requirements-Race to the Top-Early Learning Challenge; Phase 2

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-20

... DEPARTMENT OF EDUCATION 34 CFR Chapter II DEPARTMENT OF HEALTH AND HUMAN SERVICES 45 CFR Subtitle... Requirements--Race to the Top--Early Learning Challenge; Phase 2 AGENCY: Department of Education and Department of Health and Human Services. ACTION: Proposed requirements. SUMMARY: The Secretary of Education and...

Adverse effects of meglumine diatrizoate on renal function in the early post-transplant period.

PubMed

Light, J A; Perloff, L J; Etheredge, E E; Hill, G; Spees, E K

1975-11-01

Thirty-four renal transplant recipients received drip infusion urograms from 2-24 days post-transplantation. Twenty-two patients exhibited changes in renal function within 1-4 days of the urogram that were indistinguishable from allograft rejection: a tender, swollen kidney, elevation of serum creatinine, oliguria, decreased urine sodium concentration, weight gain, and hypertension. Two patients developed acute tubular necrosis and required hemodialysis, but renal function in the remaining 20 patients improved after therapy for "graft rejection" with i.v. methyprednisolone sodium succinnate. Kidneys from older-age donors that were functioning suboptimally and kidneys which exhibited subsequent clinical allograft rejection were more at risk for contrast media toxicity. This suggests that occult vascular lesions may have been present in the allograft which were exacerbated when exposed to the irritant vascular effects of contrast media, producing a mild, reversible toxic nephritis. However, several kidneys with normal function and several kidneys which never exhibited rejection activity were also adversely affected by exposure to contrast media. It appears these agents should be used cautiously, if at all, in the early post-transplant period.

Type I intrinsically photosensitive retinal ganglion cells of early post-natal development correspond to the M4 subtype.

PubMed

Sexton, Timothy J; Bleckert, Adam; Turner, Maxwell H; Van Gelder, Russell N

2015-06-21

Intrinsically photosensitive retinal ganglion cells (ipRGCs) mediate circadian light entrainment and the pupillary light response in adult mice. In early development these cells mediate different processes, including negative phototaxis and the timing of retinal vascular development. To determine if ipRGC physiologic properties also change with development, we measured ipRGC cell density and light responses in wild-type mouse retinas at post-natal days 8, 15 and 30. Melanopsin-positive cell density decreases by 17% between post-natal days 8 and 15 and by 25% between days 8 and 30. This decrease is due specifically to a decrease in cells co-labeled with a SMI-32, a marker for alpha-on ganglion cells (corresponding to adult morphologic type M4 ipRGCs). On multi-electrode array recordings, post-natal day 8 (P8) ipRGC light responses show more robust firing, reduced adaptation and more rapid recovery from short and extended light pulses than do the light responses of P15 and P30 ipRGCs. Three ipRGC subtypes - Types I-III - have been defined in early development based on sensitivity and latency on multielectrode array recordings. We find that Type I cells largely account for the unique physiologic properties of P8 ipRGCs. Type I cells have previously been shown to have relatively short latencies and high sensitivity. We now show that Type I cells show have rapid and robust recovery from long and short bright light exposures compared with Type II and III cells, suggesting differential light adaptation mechanisms between cell types. By P15, Type I ipRGCs are no longer detectable. Loose patch recordings of P8 M4 ipRGCs demonstrate Type I physiology. Type I ipRGCs are found only in early development. In addition to their previously described high sensitivity and rapid kinetics, these cells are uniquely resistant to adaptation and recover quickly and fully to short and prolonged light exposure. Type I ipRGCs correspond to the SMI-32 positive, M4 subtype and largely lose

The practical application of adaptive study design in early phase clinical trials: a retrospective analysis of time savings.

PubMed

Lorch, U; Berelowitz, K; Ozen, C; Naseem, A; Akuffo, E; Taubel, J

2012-05-01

The interest in adaptive study design is evident from the growing amount of clinical research employing this model in the mid to later stages of medicines development. Little has been published on the practical application and merits of adaptive study design in early phase clinical research. This paper describes a retrospective analysis performed on a sample of 29 industry lead adaptive early phase studies commencing between 1 January 2006 and 31 December 2010 in a clinical trials unit in London, England. All studies containing at least one adaptive feature in the original protocol were included in the analysis. The scope of the analysis was to assess whether the use of adaptive study designs provided tangible benefits over the use of conventional study designs using time savings as the main measure. We conclude that the use of adaptive study design saves time in early phase research programs. This is achieved by abolishing the need for substantial amendments or by mitigating their impact on timelines and by using adaptive scheduling efficiencies.

Benefits of PEGylation in the early post-transplant period of intraportal islet transplantation as assessed by magnetic resonance imaging of labeled islets.

PubMed

Jin, Sang-Man; Oh, Seung-Hoon; Oh, Bae Jun; Suh, Sunghwan; Bae, Ji Cheol; Lee, Jung Hee; Lee, Myung-Shik; Lee, Moon-Kyu; Kim, Kwang-Won; Kim, Jae Hyeon

2014-01-01

While a few studies have demonstrated the benefit of PEGylation in islet transplantation, most have employed renal subcapsular models and none have performed direct comparisons of islet mass in intraportal islet transplantation using islet magnetic resonance imaging (MRI). In this study, our aim was to demonstrate the benefit of PEGylation in the early post-transplant period of intraportal islet transplantation with a novel algorithm for islet MRI. Islets were PEGylated after ferucarbotran labeling in a rat syngeneic intraportal islet transplantation model followed by comparisons of post-transplant glycemic levels in recipient rats infused with PEGylated (n = 12) and non-PEGylated (n = 13) islets. The total area of hypointense spots and the number of hypointense spots larger than 1.758 mm(2) of PEGylated and non-PEGylated islets were quantitatively compared. The total area of hypointense spots (P < 0.05) and the number of hypointense spots larger than 1.758 mm(2) (P < 0.05) were higher in the PEGylated islet group 7 and 14 days post translation (DPT). These results translated into better post-transplant outcomes in the PEGylated islet group 28 DPT. In validation experiments, MRI parameters obtained 1, 7, and 14 DPT predicted normoglycemia 4 wk post-transplantation. We directly demonstrated the benefit of islet PEGylation in protection against nonspecific islet destruction in the early post-transplant period of intraportal islet transplantation using a novel algorithm for islet MRI. This novel algorithm could serve as a useful tool to demonstrate such benefit in future clinical trials of islet transplantation using PEGylated islets.

White matter changes in early phase schizophrenia and cannabis use: an update and systematic review of diffusion tensor imaging studies.

PubMed

Cookey, Jacob; Bernier, Denise; Tibbo, Philip G

2014-07-01

The impact of cannabis use on the brain tissue is still unclear, both in the healthy developing brain and in people with schizophrenia. The focus of this review is on white matter, the primary connective infrastructure of the brain. We systematically reviewed diffusion tensor imaging (DTI) studies of early phase schizophrenia (illness effect), of cannabis use in otherwise healthy brains (drug effect), and of early phase schizophrenia with cannabis use (combined effects). Studies had to include a healthy, non-cannabis using, control group as well as report on fractional anisotropy as it is the most commonly used DTI index. We excluded cohorts with heavy alcohol or illicit drug use and studies with a sample size of less than 20 in the clinical group. We retained 17 studies of early phase schizophrenia, which together indicate deficits in white matter integrity observed in all fiber tract families, but most frequently in association, callosal and projection fibers. In otherwise healthy cannabis users (2 studies), deficits in white matter tracts were reported mainly in callosal fibers, but also in projection and limbic fibers. In cannabis users with early phase schizophrenia (1 study), deficits in white matter integrity were also observed in all fiber tract families, except for limbic fibers. The current literature points to several families of white matter tracts being differentially affected in early phase schizophrenia. Further work is required to reveal the impact of cannabis use in otherwise healthy people as well as those with schizophrenia. Paucity of available studies as well as restricting analysis to FA values represent the main limitations of this review. Copyright © 2014 Elsevier B.V. All rights reserved.

Grassland biodiversity bounces back from long-term nitrogen addition.

PubMed

Storkey, J; Macdonald, A J; Poulton, P R; Scott, T; Köhler, I H; Schnyder, H; Goulding, K W T; Crawley, M J

2015-12-17

The negative effect of increasing atmospheric nitrogen (N) pollution on grassland biodiversity is now incontrovertible. However, the recent introduction of cleaner technologies in the UK has led to reductions in the emissions of nitrogen oxides, with concomitant decreases in N deposition. The degree to which grassland biodiversity can be expected to 'bounce back' in response to these improvements in air quality is uncertain, with a suggestion that long-term chronic N addition may lead to an alternative low biodiversity state. Here we present evidence from the 160-year-old Park Grass Experiment at Rothamsted Research, UK, that shows a positive response of biodiversity to reducing N addition from either atmospheric pollution or fertilizers. The proportion of legumes, species richness and diversity increased across the experiment between 1991 and 2012 as both wet and dry N deposition declined. Plots that stopped receiving inorganic N fertilizer in 1989 recovered much of the diversity that had been lost, especially if limed. There was no evidence that chronic N addition has resulted in an alternative low biodiversity state on the Park Grass plots, except where there has been extreme acidification, although it is likely that the recovery of plant communities has been facilitated by the twice-yearly mowing and removal of biomass. This may also explain why a comparable response of plant communities to reduced N inputs has yet to be observed in the wider landscape.

Grassland biodiversity bounces back from long-term nitrogen addition

NASA Astrophysics Data System (ADS)

Storkey, J.; MacDonald, A. J.; Poulton, P. R.; Scott, T.; Köhler, I. H.; Schnyder, H.; Goulding, K. W. T.; Crawley, M. J.

2015-12-01