Sample records for soft reverse characteristics

  1. Magnetic interactions in anisotropic Nd-Dy-Fe-Co-B/α-Fe multilayer magnets

    NASA Astrophysics Data System (ADS)

    Dai, Z. M.; Liu, W.; Zhao, X. T.; Han, Z.; Kim, D.; Choi, C. J.; Zhang, Z. D.

    2016-10-01

    The magnetic properties and the possible interaction mechanisms of anisotropic soft- and hard-magnetic multilayers have been investigated by altering the thickness of different kinds of spacer layers. The metal Ta and the insulating oxides MgO, Cr2O3 have been chosen as spacer layers to investigate the characteristics of the interactions between soft- and hard-magnetic layers in the anisotropic Nd-Dy-Fe-Co-B/α-Fe multilayer system. The dipolar and exchange interaction between hard and soft phases are evaluated with the help of the first order reversal curve method. The onset of the nucleation field and the magnetization reversal by domain wall movement are also evident from the first-order-reversal-curve measurements. Reversible/irreversible distributions reveal the natures of the soft- and hard-magnetic components. Incoherent switching fields are observed and the calculations show the semiquantitative contributions of hard and soft components to the system. An antiferromagnetic spacer layer will weaken the interaction between ferromagnetic layers and the effective interaction length decreases. As a consequence, the dipolar magnetostatic interaction may play an important role in the long-range interaction in anisotropic multilayer magnets.

  2. Asymmetric anode and cathode extraction structure fast recovery diode

    NASA Astrophysics Data System (ADS)

    Xie, Jiaqiang; Ma, Li; Gao, Yong

    2018-05-01

    This paper presents an asymmetric anode structure and cathode extraction fast and soft recovery diode. The device anode is partial-heavily doped and partial-lightly doped. The P+ region is introduced into the cathode. Firstly, the characteristics of the diode are simulated and analyzed. Secondly, the diode was fabricated and its characteristics were tested. The experimental results are in good agreement with the simulation results. The results show that, compared with the P–i–N diode, although the forward conduction characteristic of the diode is declined, the reverse recovery peak current is reduced by 47%, the reverse recovery time is shortened by 20% and the softness factor is doubled. In addition, the breakdown voltage is increased by 10%. Project supported by the National Natural Science Foundation of China (No. 51177133).

  3. CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES: Research on reverse recovery characteristics of SiGeC p-i-n diodes

    NASA Astrophysics Data System (ADS)

    Gao, Yong; Liu, Jing; Yang, Yuan

    2008-12-01

    This paper analyses the reverse recovery characteristics and mechanism of SiGeC p-i-n diodes. Based on the integrated systems engineering (ISE) data, the critical physical models of SiGeC diodes are proposed. Based on hetero-junction band gap engineering, the softness factor increases over six times, reverse recovery time is over 30% short and there is a 20% decrease in peak reverse recovery current for SiGeC diodes with 20% of germanium and 0.5% of carbon, compared to Si diodes. Those advantages of SiGeC p-i-n diodes are more obvious at high temperature. Compared to lifetime control, SiGeC technique is more suitable for improving diode properties and the tradeoff between reverse recovery time and forward voltage drop can be easily achieved in SiGeC diodes. Furthermore, the high thermal-stability of SiGeC diodes reduces the costs of further process steps and offers more freedoms to device design.

  4. Monte Carlo study of magnetization reversal in the model of a hard/soft magnetic bilayer

    NASA Astrophysics Data System (ADS)

    Taaev, T. A.; Khizriev, K. Sh.; Murtazaev, A. K.

    2017-06-01

    Magnetization reversal in the model of a hard/soft magnetic bilayer under the action of an external magnetic field has been investigated by the Monte Carlo method. Calculations have been performed for three systems: (i) the model without a soft-magnetic layer (hard-magnetic layer), (ii) the model with a soft-magnetic layer of thickness 25 atomic layers (predominantly exchange-coupled system), and (iii) with 50 (weak exchange coupling) atomic layers. The effect of a soft-magnetic phase on the magnetization reversal of the magnetic bilayer and on the formation of a 1D spin spring in the magnetic bilayer has been demonstrated. An inf lection that has been detected on the arch of the hysteresis loop only for the system with weak exchange coupling is completely determined by the behavior of the soft layer in the external magnetic field. The critical fields of magnetization reversal decrease with increasing thickness of the soft phase.

  5. Reversible Rigidity Control Using Low Melting Temperature Alloys

    NASA Astrophysics Data System (ADS)

    Shan, Wanliang; Lu, Tong; Majidi, Carmel

    2013-03-01

    Inspired by nature, materials able to achieve rapid rigidity changes have important applications for human body protection in military and many other areas. This talk presents the fabrication and design of soft-matter technologies that exhibit rapid reversible rigidity control. Fabricated with a masked deposition technique, the soft-matter composite contains liquid-phase and phase-changing metal alloys embedded in a soft and highly stretchable elastomer. The composite material can reversibly change its rigidity by three orders of magnitude and sustain large deformation.

  6. Thin SOI lateral IGBT with band-to-band tunneling mechanism

    NASA Astrophysics Data System (ADS)

    Fu, Qiang; Tang, Zhaohuan; Tan, Kaizhou; Wang, Zhikuan; Mei, Yong

    2017-06-01

    In this paper, a novel 200V lateral IGBT on thin SOI layer with a band-to-band tunneling junction near the anode is proposed. The structure and the operating mechanism of the proposed IGBT are described and discussed. Its main feature is that the novel IGBT structure has a unique abrupt doped p++/n++ tunneling junction in the side of the anode. By utilizing the reverse bias characteristics of the tunneling junction, the proposed IGBT can achieve excellent reverse conducting performance. Numerical simulations suggest that a low reverse conduction voltage drop VR=-1.6V at a current density of 100A/cm2 and a soft factor S=0.63 of the build-in diode are achieved.

  7. Reverse radial artery flap for soft tissue defects of hand in pediatric age group.

    PubMed

    Cheema, Saeed Ashraf; Talaat, Nabeela

    2009-01-01

    To highlight the usefulness of reverse radial artery flap in covering various soft tissue defects of hand in paediatric age group. A total of 16 reverse radial artery flaps were utilized in a period of three years to cover various soft tissue defects of hand for paediatric age group patients. The age ranged from 5-18 years. The two common causes of soft tissue defects in this series were mechanical trauma and fireworks trauma with five cases in each group. Three of the cases were burn victims and other two presented with earth quake injuries. One patient had wound because of road traffic accident. Soft tissue defects of palm were covered with this flap in eight cases while in three cases it was wrapped around the thumb. First web space defects were covered with this flap in two cases. Two cases required coverage of amputation stump at transmetacarpal level and yet another required a big flap to cover the soft tissue defects at palm, dorsum and thumb. Donor site was covered with split skin graft in all cases but one, which was closed primarily. We had partial loss of flap in one case. Grafted donor sites healed uneventfully and were quite acceptable to the patients in due course of time. Reverse radial artery flap has a quite long arc of rotation which brings it great ease to cover the soft tissue defects of various areas of hand like palm, dorsum, first web space and thumb.

  8. Muscular activation during reverse and non-reverse chewing cycles in unilateral posterior crossbite.

    PubMed

    Piancino, Maria Grazia; Farina, Dario; Talpone, Francesca; Merlo, Andrea; Bracco, Pietro

    2009-04-01

    The aim of this study was to characterize the kinematics and masseter muscle activation in unilateral posterior crossbite. Eighty-two children (8.6 +/- 1.3 yr of age) with unilateral posterior crossbite and 12 children (8.9 +/- 0.6 yr of age) with normal occlusion were selected for the study. Electromyography (EMG) and kinematics were concurrently recorded during mastication of a soft bolus and a hard bolus. The percentage of reverse cycles in the group of patients was 59.0 +/- 33.1% (soft bolus) and 69.7 +/- 29.7% (hard bolus) when chewing on the crossbite side. When chewing on the non-affected side, the number of reverse cycles was 16.7 +/- 24.5% (soft bolus) and 16.7 +/- 22.3% (hard bolus). The reverse cycles on the crossbite side were narrower with respect to the cycles on the non-affected side. Although both types of cycles in patients resulted in lower EMG activity of the masseter of the crossbite side than of the contralateral masseter, the activity of the non-affected side was larger for reverse than for non-reverse cycles. It was concluded that when chewing on the crossbite side, the masseter activity is reduced on the mastication side (crossbite) and is unaltered (non-reverse cycles) or increased (reverse) on the non-affected side.

  9. Tailoring superelasticity of soft magnetic materials

    NASA Astrophysics Data System (ADS)

    Cremer, Peet; Löwen, Hartmut; Menzel, Andreas M.

    2015-10-01

    Embedding magnetic colloidal particles in an elastic polymer matrix leads to smart soft materials that can reversibly be addressed from outside by external magnetic fields. We discover a pronounced nonlinear superelastic stress-strain behavior of such materials using numerical simulations. This behavior results from a combination of two stress-induced mechanisms: a detachment mechanism of embedded particle aggregates and a reorientation mechanism of magnetic moments. The superelastic regime can be reversibly tuned or even be switched on and off by external magnetic fields and thus be tailored during operation. Similarities to the superelastic behavior of shape-memory alloys suggest analogous applications, with the additional benefit of reversible switchability and a higher biocompatibility of soft materials.

  10. What's new with phentolamine mesylate: a reversal agent for local anaesthesia?

    PubMed

    Yagiela, John A

    2011-01-01

    Phentolamine mesylate (OraVerse), a nonselective a-adrenergic blocking drug, is the first therapeutic agent marketed for the reversal of soft-tissue anaesthesia and the associated functional deficits resulting from an intraoral submucosal injection of a local anaesthetic containing a vasoconstrictor. In clinical trials, phentolamine injected in doses of 0.2 to 0.8 mg (0.5 to 2 cartridges), as determined by patient age and volume of local anaesthetic administered, significantly hastened the return of normal soft-tissue sensation in adults and children 6 years of age and older. Median lip recovery times were reduced by 75 to 85 minutes. Functional deficits, such as drooling and difficulty in drinking, smiling, or talking--and subjects' perception of altered function or appearance--were consistently resolved by the time sensation to touch had returned to normal. Adverse effects of phentolamine injected in approved doses for reversal of local anaesthesia in patients ranging in age from 4 to 92 years were similar in incidence to those of sham injections, and no serious adverse events caused by such use were reported. The clinical use of phentolamine is viewed favorably by dentists who have administered the drug and by patients who have received it. Optimal use may require some modifications of the technique described in the package insert; cost of the agent may be influencing its widespread adoption into clinical practice. Phentolamine mesylate, in the form of OraVerse (Novalar Pharmaceuticals, San Diego, USA) represents a new therapeutic class of drugs in dentistry intended to reverse soft-tissue anaesthesia after nonsurgical dental procedures (e.g., restorative or deep scaling/root planing procedures). As shown in Figure 1, OraVerse is manufactured in 1.7 mL dental cartridges, each of which contains 0.4 mg active drug. This review describes the development of phentolamine as a dental drug, its pharmacologic characteristics, and how it may be used in clinical practice to improve patient care.

  11. Soft shell clams Mya arenaria with disseminated neoplasia demonstrate reverse transcriptase activity

    USGS Publications Warehouse

    House, M.L.; Kim, C.H.; Reno, P.W.

    1998-01-01

    Disseminated neoplasia (DN), a proliferative cell disorder of the circulatory system of bivalves, was first reported in oysters in 1969. Since that time, the disease has been determined to be transmissible through water-borne exposure, but the etiological agent has not been unequivocally identified. In order to determine if a viral agent, possibly a retrovirus, could be the causative agent of DN, transmission experiments were performed, using both a cell-free filtrate and a sucrose gradient-purified preparation of a cell-free filtrate of DN positive materials. Additionally, a PCR-enhanced reverse transcriptase assay was used to determine if reverse transcriptase was present in tissues or hemolymph from DN positive soft shell clams Mya arenaria. DN was transmitted to healthy clams by injection with whole DN cells, but not with cell-free flitrates prepared from either tissues from DN positive clams, or DN cells. The cell-free preparations from DN-positive tissues and hemolymph having high levels of DN cells in circulation exhibited positive reactions in the PCR-enhanced reverse transcriptase assay. Cell-free preparations of hemolymph from clams having low levels of DN (<0.1% of cells abnormal), hemocytes from normal soft shell clams, and normal soft shell clam tissues did not produce a positive reaction in the PCR enhanced reverse transcriptase assay.

  12. Probing interfacial characteristics of rubrene/pentacene and pentacene/rubrene bilayers with soft X-ray spectroscopy.

    PubMed

    Seo, J H; Pedersen, T M; Chang, G S; Moewes, A; Yoo, K-H; Cho, S J; Whang, C N

    2007-08-16

    The electronic structure of rubrene/pentacene and pentacene/rubrene bilayers has been investigated using soft X-ray absorption spectroscopy, resonant X-ray emission spectroscopy, and density-functional theory calculations. X-ray absorption and emission measurements reveal that it has been possible to alter the lowest unoccupied and the highest occupied molecular orbital states of rubrene in rubrene/pentacene bilayer. In the reverse case, one gets p* molecular orbital states originating from the pentacene layer. Resonant X-ray emission spectra suggest a reduction in the hole-transition probabilities for the pentacene/rubrene bilayer in comparison to reference pentacene layer. For the rubrenepentacene structure, the hole-transition probability shows an increase in comparison to the rubrene reference. We also determined the energy level alignment of the pentacene-rubrene interface by using X-ray and ultraviolet photoelectron spectroscopy. From these comparisons, it is found that the electronic structure of the pentacene-rubrene interface has a strong dependence on interface characteristics which depends on the order of the layers used.

  13. Dynamic origin of segment magnetization reversal in thin-film Penrose tilings

    NASA Astrophysics Data System (ADS)

    Montoncello, F.; Giovannini, L.; Farmer, B.; De Long, L.

    2017-02-01

    We investigate the low-frequency spin wave dynamics involved in the magnetization reversal of a Penrose P2 tiling using the dynamical matrix method. This system consists of a two-dimensional, connected wire network of elongated thin-film segments, whose complete reversal occurs as a cascade of successive local segment reversals. Using soft mode theory, we interpret the reversal of an individual segment as a first order magnetic transition, in which magnetization curve of the system suffers a small discontinuity. Near this discontinuity a specific mode of the spin wave spectrum goes soft (i.e., its frequency goes to zero), triggering a local instability of the magnetization. We show that this mode is localized, and is at the origin of the local reversal. We discuss the correlation of the mode spatial profile with the ;reversal mechanism;, which is the passage of a domain wall through the segment. This process differs from reversal in periodic square or honeycomb artificial spin ices, where a cascade of reversing segments (e.g., ;Dirac string;) follows an extended (though irregular) path across the sample; here the spatial distribution of successive segment reversals is discontinuous, but strictly associated with the area where a soft mode is localized. The migration of the localization area across the P2 tiling (during reversal in decreasing applied fields) depends on changes in the internal effective field map. We discuss these results in the context of spin wave localization due to the unique topology of the P2 tiling.

  14. Photoresponsive Polymer Surfaces

    NASA Astrophysics Data System (ADS)

    Anastasiadis, Spiros H.; Lygeraki, M. I.; Lakiotaki, K.; Varda, M.; Athanassiou, A.; Farsari, M.; Fotakis, C.

    2007-03-01

    Photochromic spiropyran molecules are utilized as additives for the development of polymer surfaces whose wetting characteristics can reversibly respond to irradiation with laser beams of properly chosen photon energy. The hydrophilicity is enhanced upon UV laser irradiation since the embedded non-polar spiropyran molecules convert to their polar merocyanine isomers, which is reversed upon green laser irradiation. Micropatterning of the photochromic-polymer films using soft lithography or photo-polymerization techniques affects their wettability towards a more hydrophobic or more hydrophilic behavior depending on the dimensions of the patterned features and on the hydrophilicity-hydrophobicity of the flat surface. The light-induced wettability variations of the structured surfaces are enhanced by up to a factor of three as compared to those on the flat surfaces. This enhancement is attributed to the photoinduced reversible volume changes to the imprinted gratings, which additionally contribute to the wettability changes due to the light-induced photochromic interconversions.

  15. Supracolloidal fullerene-like cages: design principles and formation mechanisms.

    PubMed

    Li, Zhan-Wei; Zhu, You-Liang; Lu, Zhong-Yuan; Sun, Zhao-Yan

    2016-11-30

    How to create novel desired structures by rational design of building blocks represents a significant challenge in materials science. Here we report a conceptually new design principle for creating supracolloidal fullerene-like cages through the self-assembly of soft patchy particles interacting via directional nonbonded interactions by mimicking non-planar sp 2 hybridized carbon atoms in C 60 . Our numerical investigations demonstrate that the rational design of patch configuration, size, and interaction can drive soft three-patch particles to reversibly self-assemble into a vast collection of supracolloidal fullerene-like cages. We further elucidate the formation mechanisms of supracolloidal fullerene-like cages by analyzing the structural characteristics and the formation process. Our results provide conceptual and practical guidance towards the experimental realization of supracolloidal fullerene-like cages, as well as a new perspective on understanding the fullerene formation mechanisms.

  16. Histopathologic evaluation of the effects of etodolac in established adjuvant arthritis in rats: evidence for reversal of joint damage.

    PubMed

    Weichman, B M; Chau, T T; Rona, G

    1987-04-01

    Histopathologic evaluation of hindpaws from control rats with established adjuvant arthritis showed severe alterations in soft tissue and bone, as well as progressive, moderate-to-severe articular changes. Following treatment with etodolac for 28 days, soft tissue and articular changes were rated mild, and bone changes were rated moderate, but with remodeling. These findings indicate that etodolac partially reversed the joint damage in these rats.

  17. Composite Pillars with a Tunable Interface for Adhesion to Rough Substrates

    PubMed Central

    2016-01-01

    The benefits of synthetic fibrillar dry adhesives for temporary and reversible attachment to hard objects with smooth surfaces have been successfully demonstrated in previous studies. However, surface roughness induces a dramatic reduction in pull-off stresses and necessarily requires revised design concepts. Toward this aim, we introduce cylindrical two-phase single pillars, which are composed of a mechanically stiff stalk and a soft tip layer. Adhesion to smooth and rough substrates is shown to exceed that of conventional pillar structures. The adhesion characteristics can be tuned by varying the thickness of the soft tip layer, the ratio of the Young’s moduli and the curvature of the interface between the two phases. For rough substrates, adhesion values similar to those obtained on smooth substrates were achieved. Our concept of composite pillars overcomes current practical limitations caused by surface roughness and opens up fields of application where roughness is omnipresent. PMID:27997118

  18. Treatment techniques for the recycling of bottle washing water in the soft drinks industry.

    PubMed

    Ramirez Camperos, E; Mijaylova Nacheva, P; Diaz Tapia, E

    2004-01-01

    The soft drink production is an important sector in the manufacturing industry of Mexico. Water is the main source in the production of soft drinks. Wastewater from bottle washing is almost 50% of the total wastewater generated by this industry. In order to reduce the consumption of water, the water of the last bottle rinse can be reused in to the bottle pre-rinse and pre-washing cycles. This work presents the characterization of the final bottle washing rinse discharge and the treatability study for the most appropriate treatment system for recycling. Average characteristics of the final bottle wash rinse were as follows: Turbidity 40.46 NTU, COD 47.7 mg/L, TSS 56 mg/L, TS 693.6 mg/L, electrical conductivity 1,194 microS/cm. The results of the treatability tests showed that the final rinse water can be used in the pre-rinse and pre-washing after removing the totality of the suspended solids, 80% of the COD and 75% of the dissolved solids. This can be done using the following treatment systems: filtration-adsorption-reverse osmosis, or filtration-adsorption-ion exchange. The installation of these treatment techniques in the soft drink industry would decrease bottle washing water consumption by 50%.

  19. End-on soft x ray imaging of Field-Reversed Configurations (FRCs) on the Field-Reversal-C (FRX-C)/Large Scale Modification (LSM) experiment

    NASA Astrophysics Data System (ADS)

    Taggart, D. P.; Gribble, R. J.; Bailey, A. D., III; Sugimoto, S.

    Recently, a prototype soft x ray pinhole camera was fielded on FRX-C/LSM at Los Alamos and TRX at Spectra Technology. The soft x ray FRC images obtained using this camera stand out in high contrast to their surroundings. It was particularly useful for studying the FRC during and shortly after formation when, at certain operating conditions, flute-like structures at the edge and internal structures of the FRC were observed which other diagnostics could not resolve. Building on this early experience, a new soft x ray pinhole camera was installed on FRX-C/LSM, which permits more rapid data acquisition and briefer exposures. It will be used to continue studying FRC formation and to look for internal structure later in time which could be a signature of instability. The initial operation of this camera is summarized.

  20. Reversing drug resistance of soft tumor-repopulating cells by tumor cell-derived chemotherapeutic microparticles

    PubMed Central

    Ma, Jingwei; Zhang, Yi; Tang, Ke; Zhang, Huafeng; Yin, Xiaonan; Li, Yong; Xu, Pingwei; Sun, Yanling; Ma, Ruihua; Ji, Tiantian; Chen, Junwei; Zhang, Shuang; Zhang, Tianzhen; Luo, Shunqun; Jin, Yang; Luo, Xiuli; Li, Chengyin; Gong, Hongwei; Long, Zhixiong; Lu, Jinzhi; Hu, Zhuowei; Cao, Xuetao; Wang, Ning; Yang, Xiangliang; Huang, Bo

    2016-01-01

    Developing novel approaches to reverse the drug resistance of tumor-repopulating cells (TRCs) or stem cell-like cancer cells is an urgent clinical need to improve outcomes of cancer patients. Here we show an innovative approach that reverses drug resistance of TRCs using tumor cell-derived microparticles (T-MPs) containing anti-tumor drugs. TRCs, by virtue of being more deformable than differentiated cancer cells, preferentially take up T-MPs that release anti-tumor drugs after entering cells, which in turn lead to death of TRCs. The underlying mechanisms include interfering with drug efflux and promoting nuclear entry of the drugs. Our findings demonstrate the importance of tumor cell softness in uptake of T-MPs and effectiveness of a novel approach in reversing drug resistance of TRCs with promising clinical applications. PMID:27167569

  1. Development, beam characterization and chromosomal effectiveness of X-rays of RBC characteristic X-ray generator.

    PubMed

    Endo, Satoru; Hoshi, Masaharu; Takada, Jun; Takatsuji, Toshihiro; Ejima, Yosuke; Saigusa, Shin; Tachibana, Akira; Sasaki, Masao S

    2006-06-01

    A characteristic hot-filament type X-ray generator was constructed for irradiation of cultured cells. The source provides copper K, iron K, chromium K, molybdenum L, aluminium K and carbon K shell characteristic X-rays. When cultured mouse m5S cells were irradiated and frequencies of dicentrics were fitted to a linear-quadratic model, Y = alphaD + betaD2, the chromosomal effectiveness was not a simple function of photon energy. The alpha-terms increased with the decrease of the photon energy and then decreased with further decrease of the energy with an inflection point at around 10 keV. The beta-terms stayed constant for the photon energy down to 10 keV and then increased with further decrease of energy. Below 10 keV, the relative biological effectiveness (RBE) at low doses was proportional to the photon energy, which contrasted to that for high energy X- or gamma-rays where the RBE was inversely related with the photon energy. The reversion of the energy dependency occurred at around 1-2 Gy, where the RBE of soft X-rays was insensitive to X-ray energy. The reversion of energy-RBE relation at a moderate dose may shed light on the controversy on energy dependency of RBE of ultrasoft X-rays in cell survival experiments.

  2. [Repairing of soft tissue defect in leg by free vascularized thoracoumbilical flap with reversed flow].

    PubMed

    Xu, Y Q; Li, Z Y; Li, J

    2000-11-01

    To investigate the clinical effect of free vascularized thoracoumbilical flap with reversal flow in repairing the soft tissue defect in leg with tibia exposure. Forty-four casting mould specimens of leg arteries were studied firstly. Then 25 cases with soft tissue defect and tibia exposure in the proximal-middle segment of leg were adopted in this study. Among them, 18 cases had long distance thrombosis of the anterior tibial vessels or posterior tibial vessels due to traumatic lesion. The maximal size of defect was 28 cm x 11 cm and the minimal size of defect was 11 cm x 9 cm. In operation, the thoracoumbilical flap which was based on the inferior epigastric vessels was anastomosed to the distal end of the anterior tibial vessels or posterior tibial vessels. Anterior tibial artery, posterior tibial artery and fibular artery had rich communication branches in foot and ankle. All the flaps survived, the color and cosmetic result of them were good. The free vascularized thoracoumbilical flap with reversed flow is practical in repairing the soft tissue defect of leg with tibia exposure. Either the anterior tibial vessels or the posterior tibial vessels is normal, and the distal end of injured blood vessels is available, this technique can be adopted.

  3. Reverse lyotropic liquid crystals from europium nitrate and P123 with enhanced luminescence efficiency.

    PubMed

    Yi, Sijing; Li, Qintang; Liu, Hongguo; Chen, Xiao

    2014-10-02

    Fabrication of lyotropic aggregates containing the lanthanide ions is becoming a preferable way to prepare novel functional materials. Here, the lyotropic liquid crystals (LLCs) of reverse hexagonal, reverse bicontinuous cubic, and lamellar phases have been constructed in sequence directly from the mixtures of Eu(NO3)3·6H2O and Pluronic P123 amphiphilc block copolymer with increasing the salt proportion. Their phase types and structural characteristics were analyzed using polarized optical microscopy (POM) and small-angle X-ray scattering (SAXS) measurements. The driving forces of reverse LLC phase formation were investigated using Fourier-transformed infrared spectroscopy (FTIR) and rheological measurements. The hydrated europium salt was found to act not only as a solvent here, but also as the bridge to form hydrogen bonding between coordinated water molecules and PEO blocks, which played a key role in the reverse LLCs formation. Compared to those in aqueous solutions and solid state, the enhanced luminescence quantum yields and prolonged excited state lifetimes were observed in two europium containing reverse mesophases. The luminescence quenching effect of lanthanide ions was efficiently suppressed, probably due to the substitution of coordinated water molecules by oxyethyl groups of P123 and ordered phase structures of LLCs, where the coordinated europium ions were confined and isolated by PEO blocks. The optimum luminescence performance was then found to exist in the reverse hexagonal phase. The obtained results on such lanthanide-induced reverse LLCs should be referable for designing new luminescent soft materials construction to expand their application fields.

  4. Fabrication of ferroelectric polymer nanostructures on flexible substrates by soft-mold reverse nanoimprint lithography

    NASA Astrophysics Data System (ADS)

    Song, Jingfeng; Lu, Haidong; Li, Shumin; Tan, Li; Gruverman, Alexei; Ducharme, Stephen

    2016-01-01

    Conventional nanoimprint lithography with expensive rigid molds is used to pattern ferroelectric polymer nanostructures on hard substrate for use in, e.g., organic electronics. The main innovation here is the use of inexpensive soft polycarbonate molds derived from recordable DVDs and reverse nanoimprint lithography at low pressure, which is compatible with flexible substrates. This approach was implemented to produce regular stripe arrays with a spacing of 700 nm from vinylidene fluoride co trifluoroethylene ferroelectric copolymer on flexible polyethylene terephthalate substrates. The nanostructures have very stable and switchable piezoelectric response and good crystallinity, and are highly promising for use in organic electronics enhanced or complemented by the unique properties of the ferroelectric polymer, such as bistable polarization, piezoelectric response, pyroelectric response, or electrocaloric function. The soft-mold reverse nanoimprint lithography also leaves little or no residual layer, affording good isolation of the nanostructures. This approach reduces the cost and facilitates large-area, high-throughput production of isolated functional polymer nanostructures on flexible substrates for the increasing application of ferroelectric polymers in flexible electronics.

  5. Fabrication of ferroelectric polymer nanostructures on flexible substrates by soft-mold reverse nanoimprint lithography.

    PubMed

    Song, Jingfeng; Lu, Haidong; Li, Shumin; Tan, Li; Gruverman, Alexei; Ducharme, Stephen

    2016-01-08

    Conventional nanoimprint lithography with expensive rigid molds is used to pattern ferroelectric polymer nanostructures on hard substrate for use in, e.g., organic electronics. The main innovation here is the use of inexpensive soft polycarbonate molds derived from recordable DVDs and reverse nanoimprint lithography at low pressure, which is compatible with flexible substrates. This approach was implemented to produce regular stripe arrays with a spacing of 700 nm from vinylidene fluoride co trifluoroethylene ferroelectric copolymer on flexible polyethylene terephthalate substrates. The nanostructures have very stable and switchable piezoelectric response and good crystallinity, and are highly promising for use in organic electronics enhanced or complemented by the unique properties of the ferroelectric polymer, such as bistable polarization, piezoelectric response, pyroelectric response, or electrocaloric function. The soft-mold reverse nanoimprint lithography also leaves little or no residual layer, affording good isolation of the nanostructures. This approach reduces the cost and facilitates large-area, high-throughput production of isolated functional polymer nanostructures on flexible substrates for the increasing application of ferroelectric polymers in flexible electronics.

  6. Soft tissue balancing in total shoulder replacement.

    PubMed

    Mueller, Maike; Hoy, Gregory

    2014-03-01

    Total shoulder arthroplasty is now capable of recreating near anatomic reproduction of native bony shoulder anatomy, but the function and longevity of anatomic shoulder replacement is dependent on a competent soft tissue envelope and adequate motoring of all musculo-tendinous units about the shoulder. Balancing the soft tissues requires understanding of the anatomy and pathology, as well as technical skills. The advent of reverse shoulder biomechanics has brought with it special requirements of understanding of the soft tissue elements still left in the shoulder despite major rotator cuff deficiency.

  7. Assessing China’s Soft Power in Asia: Implications for U.S. Strategy

    DTIC Science & Technology

    2012-04-01

    especially as it might be thought of as an instrument of policy.”19 Gray‟s critiques deride the strategic usefulness of soft 8 power based on the length...soft power flows from hard power, but not the reverse. Gray critiques soft power as if it is mutually exclusive of hard power; that is, if you use ...and film …the freedom is not there. (The Chinese government) really tries to control and manage it, and there is self- censorship as well. That is

  8. Field-Control, Phase-Transitions, and Life’s Emergence

    PubMed Central

    Mitra-Delmotte, Gargi; Mitra, A. N.

    2012-01-01

    Instances of critical-like characteristics in living systems at each organizational level (bio-molecules to ecosystems) as well as the spontaneous emergence of computation (Langton), do suggest the relevance of self-organized criticality (SOC). But extrapolating complex bio-systems to life’s origins, brings up a paradox: how could simple organics – lacking the “soft-matter” response properties of today’s complex bio-molecules – have dissipated energy from primordial reactions (eventually reducing CO2) in a controlled manner for their “ordering”? Nevertheless, a causal link of life’s macroscopic irreversible dynamics to the microscopic reversible laws of statistical mechanics is indicated via the “functional-takeover” of a soft magnetic scaffold by organics (c.f. Cairns-Smith’s “crystal-scaffold”). A field-controlled structure offers a mechanism for boot-strapping – bottom-up assembly with top-down control: its super-paramagnetic colloidal components obey reversible dynamics, but its dissipation of magnetic (H)-field energy for aggregation breaks time-reversal symmetry. The responsive adjustments of the controlled (host) mineral system to environmental changes would bring about mutual coupling between random organic sets supported by it; here the generation of long-range correlations within organic (guest) networks could include SOC-like mechanisms. And, such cooperative adjustments enable the selection of the functional configuration by altering the inorganic dipolar network’s capacity to assist a spontaneous process. A non-equilibrium dynamics could now drive the kinetically oriented system (trimming the phase-space via sterically coupled organics) toward a series of phase-transitions with appropriate organic replacements “taking-over” its functions. Where available, experiments are cited in support of these speculations and for designing appropriate tests. PMID:23060803

  9. Light-Driven Reversible Transformation between Self-Organized Simple Cubic Lattice and Helical Superstructure Enabled by a Molecular Switch Functionalized Nanocage.

    PubMed

    Zhou, Kang; Bisoyi, Hari Krishna; Jin, Jian-Qiu; Yuan, Cong-Long; Liu, Zhen; Shen, Dong; Lu, Yan-Qing; Zheng, Zhi-Gang; Zhang, Weian; Li, Quan

    2018-04-23

    Self-organized stimuli-responsive smart materials with adjustable attributes are highly desirable for a plethora of device applications. Simple cubic lattice is quite uncommon in soft condensed matter due to its lower packing factor. Achieving a stable simple cubic soft lattice and endowing such a lattice with dynamic reconstruction capability solely by a facile light irradiation are of paramount significance for both fundamental studies and engineering explorations. Herein, an elegant stable self-organized simple cubic soft lattice, i.e., blue phase II, in a chiral liquid crystal (LC) system is disclosed, which is stable down to room temperature and exhibits both reversible lattice deformation and transformation to a helical superstructure, i.e., cholesteric LC, by light stimulation. Such an amazing trait is attained by doping a judiciously designed achiral photoresponsive molecular switch functionalized polyhedral oligomeric silsesquioxane nanocage into a chiral LC host. An unprecedented reversible collapse and reconstruction of such a high symmetric simple cubic blue phase II driven by light has been achieved. Furthermore, a well-defined conglomerate micropattern composed of simple cubic soft lattice and helical superstructure, which is challenging to fabricate in organic and inorganic crystalline materials, is produced using photomasking technology. Moreover, the promising photonic application based on such a micropattern is demonstrated. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Optically reversible electrical soft-breakdown in wide-bandgap oxides—A factorial study

    NASA Astrophysics Data System (ADS)

    Zhou, Y.; Ang, D. S.; Kalaga, P. S.

    2018-04-01

    In an earlier work, we found that an electrical soft-breakdown region in wide-bandgap oxides, such as hafnium dioxide, silicon dioxide, etc., could be reversed when illuminated by white light. The effect is evidenced by a decrease in the breakdown leakage current, termed as a negative photoconductivity response. This finding raises the prospect for optical sensing applications based on these traditionally non-photo-responsive but ubiquitous oxide materials. In this study, we examine the statistical distribution for the rate of breakdown reversal as well as the influence of factors such as wavelength, light intensity, oxide stoichiometry (or oxygen content) and temperature on the reversal rate. The rate of breakdown reversal is shown to be best described by the lognormal distribution. Light in the range of ˜400-700 nm is found to have relatively little influence on the reversal rate. On the other hand, light intensity, oxygen content and temperature, each of them has a clear impact; a stronger light intensity, an oxide that is richer in oxygen content and a reduced temperature all speed up the reversal process substantially. These experimental results are consistent with the proposed phenomenological redox model involving photo-assisted recombination of the surrounding oxygen interstitials with vacancy defects in the breakdown path.

  11. Propeller Flap for Complex Distal Leg Reconstruction: A Versatile Alternative when Reverse Sural Artery Flap is Not Feasible.

    PubMed

    Ademola, Samuel A; Michael, Afieharo I; Oladeji, Femi J; Mbaya, Kefas M; Oyewole, O

    2015-01-01

    Reverse sural artery fasciocutaneous flap has become a workhorse for the reconstruction of distal leg soft tissue defects. When its use is not feasible, perforator-based propeller flap offers a better, easier, faster, and cheaper alternative to free flap. We present our experience with two men both aged 34 years who sustained Gustilo 3B injuries from gunshot. The donor area for reversed sural artery flap was involved in the injuries. They had early debridement, external fixation, and wound coverage with perforator-based propeller flaps. The donor sites were covered with skin graft. All flaps survived. There were minor wound edge ulcers due to the pressure of positioning that did not affect flap survival and the ulcers healed with conservative management. Perforator-based propeller flap is a versatile armamentarium for reconstruction of soft tissue defects of the distal leg in resource-constrained settings, especially when the donor area for a reverse flow sural flap artery is involved in the injury.

  12. Quantifying the Electrocatalytic Turnover of Vitamin B12-Mediated Dehalogenation on Single Soft Nanoparticles.

    PubMed

    Cheng, Wei; Compton, Richard G

    2016-02-12

    We report the electrocatalytic dehalogenation of trichloroethylene (TCE) by single soft nanoparticles in the form of Vitamin B12 -containing droplets. We quantify the turnover number of the catalytic reaction at the single soft nanoparticle level. The kinetic data shows that the binding of TCE with the electro-reduced vitamin in the Co(I) oxidation state is chemically reversible. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Untethered Recyclable Tubular Actuators with Versatile Locomotion for Soft Continuum Robots.

    PubMed

    Qian, Xiaojie; Chen, Qiaomei; Yang, Yang; Xu, Yanshuang; Li, Zhen; Wang, Zhenhua; Wu, Yahe; Wei, Yen; Ji, Yan

    2018-05-27

    Stimuli-responsive materials offer a distinguished platform to build tether-free compact soft robots, which can combine sensing and actuation without a linked power supply. In the past, tubular soft robots have to be made by multiple components with various internal channels or complex cavities assembled together. Moreover, robust processing, complex locomotion, simple structure, and easy recyclability represent major challenges in this area. Here, it is shown that those challenges can be tackled by liquid crystalline elastomers with allyl sulfide functional groups. The light-controlled exchange reaction between allyl sulfide groups allows flexible processing of tubular soft robots/actuators, which does not need any assisting materials. Complex locomotion demonstrated here includes reversible simultaneous bending and elongation; reversible diameter expansion; and omnidirectional bending via remote infrared light control. Different modes of actuation can be programmed into the same tube without the routine assembly of multiple tubes as used in the past. In addition, the exchange reaction also makes it possible to use the same single tube repeatedly to perform different functions by erasing and reprogramming. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. 4D Printed Actuators with Soft-Robotic Functions.

    PubMed

    López-Valdeolivas, María; Liu, Danqing; Broer, Dick Jan; Sánchez-Somolinos, Carlos

    2018-03-01

    Soft matter elements undergoing programed, reversible shape change can contribute to fundamental advance in areas such as optics, medicine, microfluidics, and robotics. Crosslinked liquid crystalline polymers have demonstrated huge potential to implement soft responsive elements; however, the complexity and size of the actuators are limited by the current dominant thin-film geometry processing toolbox. Using 3D printing, stimuli-responsive liquid crystalline elastomeric structures are created here. The printing process prescribes a reversible shape-morphing behavior, offering a new paradigm for active polymer system preparation. The additive character of this technology also leads to unprecedented geometries, complex functions, and sizes beyond those of typical thin-films. The fundamental concepts and devices presented therefore overcome the current limitations of actuation energy available from thin-films, thereby narrowing the gap between materials and practical applications. © 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Matrix stiffness reverses the effect of actomyosin tension on cell proliferation.

    PubMed

    Mih, Justin D; Marinkovic, Aleksandar; Liu, Fei; Sharif, Asma S; Tschumperlin, Daniel J

    2012-12-15

    The stiffness of the extracellular matrix exerts powerful effects on cell proliferation and differentiation, but the mechanisms transducing matrix stiffness into cellular fate decisions remain poorly understood. Two widely reported responses to matrix stiffening are increases in actomyosin contractility and cell proliferation. To delineate their relationship, we modulated cytoskeletal tension in cells grown across a physiological range of matrix stiffnesses. On both synthetic and naturally derived soft matrices, and across a panel of cell types, we observed a striking reversal of the effect of inhibiting actomyosin contractility, switching from the attenuation of proliferation on rigid substrates to the robust promotion of proliferation on soft matrices. Inhibiting contractility on soft matrices decoupled proliferation from cytoskeletal tension and focal adhesion organization, but not from cell spread area. Our results demonstrate that matrix stiffness and actomyosin contractility converge on cell spreading in an unexpected fashion to control a key aspect of cell fate.

  16. Matrix stiffness reverses the effect of actomyosin tension on cell proliferation

    PubMed Central

    Mih, Justin D.; Marinkovic, Aleksandar; Liu, Fei; Sharif, Asma S.; Tschumperlin, Daniel J.

    2012-01-01

    Summary The stiffness of the extracellular matrix exerts powerful effects on cell proliferation and differentiation, but the mechanisms transducing matrix stiffness into cellular fate decisions remain poorly understood. Two widely reported responses to matrix stiffening are increases in actomyosin contractility and cell proliferation. To delineate their relationship, we modulated cytoskeletal tension in cells grown across a physiological range of matrix stiffnesses. On both synthetic and naturally derived soft matrices, and across a panel of cell types, we observed a striking reversal of the effect of inhibiting actomyosin contractility, switching from the attenuation of proliferation on rigid substrates to the robust promotion of proliferation on soft matrices. Inhibiting contractility on soft matrices decoupled proliferation from cytoskeletal tension and focal adhesion organization, but not from cell spread area. Our results demonstrate that matrix stiffness and actomyosin contractility converge on cell spreading in an unexpected fashion to control a key aspect of cell fate. PMID:23097048

  17. Soft Wall Ion Channel in Continuum Representation with Application to Modeling Ion Currents in α-Hemolysin

    PubMed Central

    Simakov, Nikolay A.

    2010-01-01

    A soft repulsion (SR) model of short range interactions between mobile ions and protein atoms is introduced in the framework of continuum representation of the protein and solvent. The Poisson-Nernst-Plank (PNP) theory of ion transport through biological channels is modified to incorporate this soft wall protein model. Two sets of SR parameters are introduced: the first is parameterized for all essential amino acid residues using all atom molecular dynamic simulations; the second is a truncated Lennard – Jones potential. We have further designed an energy based algorithm for the determination of the ion accessible volume, which is appropriate for a particular system discretization. The effects of these models of short-range interaction were tested by computing current-voltage characteristics of the α-hemolysin channel. The introduced SR potentials significantly improve prediction of channel selectivity. In addition, we studied the effect of choice of some space-dependent diffusion coefficient distributions on the predicted current-voltage properties. We conclude that the diffusion coefficient distributions largely affect total currents and have little effect on rectifications, selectivity or reversal potential. The PNP-SR algorithm is implemented in a new efficient parallel Poisson, Poisson-Boltzman and PNP equation solver, also incorporated in a graphical molecular modeling package HARLEM. PMID:21028776

  18. Reversible Bending Behaviors of Photomechanical Soft Actuators Based on Graphene Nanocomposites.

    PubMed

    Niu, Dong; Jiang, Weitao; Liu, Hongzhong; Zhao, Tingting; Lei, Biao; Li, Yonghao; Yin, Lei; Shi, Yongsheng; Chen, Bangdao; Lu, Bingheng

    2016-06-06

    Photomechanical nanocomposites embedded with light-absorbing nanoparticles show promising applications in photoresponsive actuations. Near infrared (nIR)-responsive nanocomposites based photomechanical soft actuators can offer lightweight functional and underexploited entry into soft robotics, active optics, drug delivery, etc. A novel graphene-based photomechanical soft actuators, constituted by Polydimethylsiloxane (PDMS)/graphene-nanoplatelets (GNPs) layer (PDMS/GNPs) and pristine PDMS layer, have been constructed. Due to the mismatch of coefficient of thermal expansion of two layers induced by dispersion of GNPs, controllable and reversible bendings response to nIR light irradiation are observed. Interestingly, two different bending behaviors are observed when the nIR light comes from different sides, i.e., a gradual single-step photomechanical bending towards PDMS/GNPs layer when irradiation from PDMS side, while a dual-step bending (finally bending to the PDMS/GNPs side but with an strong and fast backlash at the time of light is on/off) when irradiation from PDMS/GNPs side. The two distinctive photomechanical bending behaviors are investigated in terms of heat transfer and thermal expansion, which reveals that the distinctive bending behaviors can be attributed to the differences in temperature gradients along the thickness when irradiation from different sides. In addition, the versatile photomechanical bending properties will provide alternative way for drug-delivery, soft robotics and microswitches, etc.

  19. Reversible Bending Behaviors of Photomechanical Soft Actuators Based on Graphene Nanocomposites

    PubMed Central

    Niu, Dong; Jiang, Weitao; Liu, Hongzhong; Zhao, Tingting; Lei, Biao; Li, Yonghao; Yin, Lei; Shi, Yongsheng; Chen, Bangdao; Lu, Bingheng

    2016-01-01

    Photomechanical nanocomposites embedded with light-absorbing nanoparticles show promising applications in photoresponsive actuations. Near infrared (nIR)-responsive nanocomposites based photomechanical soft actuators can offer lightweight functional and underexploited entry into soft robotics, active optics, drug delivery, etc. A novel graphene-based photomechanical soft actuators, constituted by Polydimethylsiloxane (PDMS)/graphene-nanoplatelets (GNPs) layer (PDMS/GNPs) and pristine PDMS layer, have been constructed. Due to the mismatch of coefficient of thermal expansion of two layers induced by dispersion of GNPs, controllable and reversible bendings response to nIR light irradiation are observed. Interestingly, two different bending behaviors are observed when the nIR light comes from different sides, i.e., a gradual single-step photomechanical bending towards PDMS/GNPs layer when irradiation from PDMS side, while a dual-step bending (finally bending to the PDMS/GNPs side but with an strong and fast backlash at the time of light is on/off) when irradiation from PDMS/GNPs side. The two distinctive photomechanical bending behaviors are investigated in terms of heat transfer and thermal expansion, which reveals that the distinctive bending behaviors can be attributed to the differences in temperature gradients along the thickness when irradiation from different sides. In addition, the versatile photomechanical bending properties will provide alternative way for drug-delivery, soft robotics and microswitches, etc. PMID:27265380

  20. Functional and nutritional characteristics of soft wheat grown in no-till and conventional cropping systems

    USDA-ARS?s Scientific Manuscript database

    The effects of no-till vs. conventional farming practices were evaluated on soft wheat functional and nutritional characteristics, including kernel physical properties, whole wheat composition, antioxidant activity and end-product quality. Soft white winter wheat cv. ORCF 102 was evaluated over a tw...

  1. Soft tissue and intra-articular injection of bupivacaine, epinephrine, and morphine has a beneficial effect after total knee arthroplasty.

    PubMed

    Lombardi, Adolph V; Berend, Keith R; Mallory, Thomas H; Dodds, Kathleen L; Adams, Joanne B

    2004-11-01

    The purpose of this study was to determine if an intraoperative intraarticular and soft-tissue injection of local anaesthetic, epinephrine, and morphine has a beneficial effect for total knee arthroplasty. A control group of 138 patients (181 knees) received no intraoperative injection. The study group of 171 patients (197 knees) received intraoperative injection of 0.25% bupivacaine with epinephrine and morphine with 2/3 injected into the soft tissues and 1/3 injected into the joint. Patients having bilateral simultaneous procedures received a divided dose. The pain treatment protocol otherwise was identical. Pain, sedation, rescue narcotic usage, narcotic reversal and blood loss were examined. Pain levels during the immediate postoperative period, blood loss, and bleeding indices were reduced with injection. Considerably more control patients required rescue doses of narcotics. Preemptive analgesia with soft tissue and intra-articular injection of long-acting local anesthetic with epinephrine and morphine provides better pain control in the immediate postoperative period, decreases blood loss, and decreases the need for rescue narcotics and reversal agents. This simple, inexpensive method provides an effective adjunct to a multimodal approach in improving the postoperative course of primary total knee arthroplasty.

  2. The Extreme Mechanics of Soft Structures

    NASA Astrophysics Data System (ADS)

    Reis, Pedro

    2015-03-01

    I will present a series of experimental investigations on the rich behavior of soft mechanical structures, which, similarly to soft materials, can undergo large deformations under a variety of loading conditions. Soft structures typically comprise slender elements that can readily undergo mechanical instabilities to achieve extreme flexibility and reversible reconfigurations. This field has came to be warmly known as `Extreme Mechanics', where one of the fundamental challenges lies in rationalizing the geometric nonlinearities that arise in the post-buckling regime. I shall focus on problems involving thin elastic rods and shells, through examples ranging from the deployment of submarine cables onto the seabed, locomotion of uniflagellar bacteria, crystallography of curved wrinkling and its usage for active aerodynamic drag reduction. The main common feature underlying this series of studies is the prominence of geometry, and its interplay with mechanics, in dictating complex mechanical behavior that is relevant and applicable over a wide range of length scales. Moreover, our findings suggest that we rethink our relationship with mechanical instabilities which, rather than modes of failure, can be embraced as opportunities for functionality that are scalable, reversible, and robust. The author knowledges financial support from the National Science Foundation, CMMI-1351449 (CAREER).

  3. Shortened penis post penile prosthesis implantation treated with subcutaneous soft silicone penile implant: case report.

    PubMed

    Shirvanian, V; Lemperle, G; Araujo Pinto, C; Elist, J J

    2014-01-01

    Penile prosthesis surgery for erectile dysfunction has the highest satisfaction rates among all treatment options but is often associated with subjective and objective loss of penile length and girth following surgery. To present a novel technique using a subcutaneous soft silicone implant for reversal of penile shortening and narrowing after prosthesis surgery, with additional gains in overall penile length and girth. Nine patients were treated with the insertion of a subcutaneous soft silicone penile implant. All patients had previously reported a loss in penile length (0.5-2 cm), and seven of nine patients also reported a loss in penile girth (0.5-2.6 cm) after penile prosthesis surgery. During a follow-up period of 4-24 months, penile length and girth measurements showed a mean increase in length of 2.4 cm (±0.75 cm) and a mean increase in girth of 3.4 cm (±0.94 cm). The additional insertion of a subcutaneous soft silicone implant in patients with decreased penile length and girth after penile prosthesis surgery is an effective treatment option that provides reversal of lost penile length and girth.

  4. Reversal of mineral ion homeostasis and soft-tissue calcification of klotho knockout mice by deletion of vitamin D 1α-hydroxylase

    PubMed Central

    Ohnishi, Mutsuko; Nakatani, Teruyo; Lanske, Beate; Razzaque, M. Shawkat

    2011-01-01

    Changes in the expression of klotho, a β-glucuronidase, contribute to the development of features that resemble those of premature aging, as well as chronic renal failure. Klotho knockout mice have increased expression of the sodium/phosphate cotransporter (NaPi2a) and 1α-hydroxylase in their kidneys, along with increased serum levels of phosphate and 1,25-dihydroxyvitamin D. These changes are associated with widespread soft-tissue calcifications, generalized tissue atrophy, and a shorter lifespan in the knockout mice. To determine the role of the increased vitamin D activities in klotho knockout animals, we generated klotho and 1α-hydroxylase double-knockout mice. These double mutants regained body weight and developed hypophosphatemia with a complete elimination of the soft-tissue and vascular calcifications that were routinely found in klotho knockout mice. The markedly increased serum fibroblast growth factor 23 and the abnormally low serum parathyroid hormone levels, typical of klotho knockout mice, were significantly reversed in the double-knockout animals. These in vivo studies suggest that vitamin D has a pathologic role in regulating abnormal mineral ion metabolism and soft-tissue anomalies of klotho-deficient mice. PMID:19225558

  5. Apparatus and method for controlling the rotary airlocks in a coal processing system by reversing the motor current rotating the air lock

    DOEpatents

    Groombridge, Clifton E.

    1996-01-01

    An improvement to a coal processing system where hard materials found in the coal may cause jamming of either inflow or outflow rotary airlocks, each driven by a reversible motor. The instantaneous current used by the motor is continually monitored and compared to a predetermined value. If an overcurrent condition occurs, indicating a jamming of the airlock, a controller means starts a "soft" reverse rotation of the motor thereby clearing the jamming. Three patterns of the motor reversal are provided.

  6. Case Report Reconstruction of Exposed Ilium With Reverse Turnover Latissimus Dorsi Muscle Flap

    PubMed Central

    Hayashida, Kenji; Endo, Yoshie; Kamebuchi, Katsuhiko

    2011-01-01

    Objective: It is difficult to cover a large skin and soft tissue defect with exposure of the ilium. We therefore performed a new reconstruction technique, using a reverse latissimus dorsi muscle flap fed by perforating branches of only the 10th intercostal artery. Methods: A 45-year-old man had a large traumatic defect located on the hip with exposure of the iliac crest. After confirming and preserving perforating branches of the 10th intercostal artery, the latissimus dorsi muscle flap was turned over just proximal to the perforating branch, and a split-thickness skin graft was performed over the flap. Results: The skin graft took place well and there were no circulation problems. Conclusions: This flap covered a larger area on the hip than the musculocutaneous flap. Furthermore, this is easier to perform and is less invasive than a vascularized free flap. Skin and soft tissue defects that expose bones of the lumbar or hip region can be reconstructed with a local flap; however, the deficit is small for this coverage and usually there is little skin and soft tissue to cover the wound defect in the surrounding area. Thus, it is often difficult to deal with large defects. We performed a reconstruction, using a reverse latissimus dorsi flap fed by perforating branches of the 10th intercostal artery for a large skin and soft tissue defect of the hip with exposure of the iliac crest, resulting in a good outcome. This technique is thought to be useful for reconstruction when the ilium is exposed, and we report the case and surgical procedure. PMID:21559059

  7. Reversal of soft-tissue local anesthesia with phentolamine mesylate in adolescents and adults.

    PubMed

    Hersh, Elliot V; Moore, Paul A; Papas, Athena S; Goodson, J Max; Navalta, Laura A; Rogy, Siegfried; Rutherford, Bruce; Yagiela, John A

    2008-08-01

    The authors conducted two multicenter, randomized, double-blinded, controlled Phase III clinical trials to study the efficacy and safety of phentolamine mesylate (PM) in shortening the duration and burden of soft-tissue anesthesia. The study involved 484 subjects who received one of four commercially available local anesthetic solutions containing vasoconstrictors for restorative or scaling procedures. On completion of the dental procedure, subjects randomly received a PM or a sham injection (an injection in which a needle does not penetrate the soft tissue) in the same site as the local anesthetic injection. The investigators measured the duration of soft-tissue anesthesia by using standardized lip- and tongue-tapping procedures every five minutes for five hours. They also evaluated functional measures and subject-perceived altered function, sensation, appearance and safety. Median recovery times in the lower lip and tongue for subjects in the PM group were 70 minutes and 60 minutes, respectively. Median recovery times in the lower lip and tongue for subjects in the sham group were 155 minutes and 125 minutes, respectively. Upper lip median recovery times were 50 minutes for subjects in the PM group and 133 minutes for subjects in the sham group. These differences were significant (P < .0001). Recovery from actual functional deficits and subject-perceived altered function, sensation and appearance also showed significant differences between the PM and the sham groups. PM was efficacious and safe in reducing the duration of local anesthetic- induced soft-tissue numbness and its associated functional deficits. Clinicians can use PM to accelerate reversal of soft-tissue anesthesia and the associated functional deficits.

  8. Soft wheat quality characteristics required for making baking powder biscuits

    USDA-ARS?s Scientific Manuscript database

    Fifteen soft wheat varieties were evaluated for their grain, milling, flour and dough mixing characteristics, as well as their solvent retention capacities (SRCs), pasting properties and suitability for making baking powder biscuits, to identify wheat quality characteristics required for making bisc...

  9. 3D Printing of Liquid Crystal Elastomeric Actuators with Spatially Programed Nematic Order.

    PubMed

    Kotikian, Arda; Truby, Ryan L; Boley, John William; White, Timothy J; Lewis, Jennifer A

    2018-03-01

    Liquid crystal elastomers (LCEs) are soft materials capable of large, reversible shape changes, which may find potential application as artificial muscles, soft robots, and dynamic functional architectures. Here, the design and additive manufacturing of LCE actuators (LCEAs) with spatially programed nematic order that exhibit large, reversible, and repeatable contraction with high specific work capacity are reported. First, a photopolymerizable, solvent-free, main-chain LCE ink is created via aza-Michael addition with the appropriate viscoelastic properties for 3D printing. Next, high operating temperature direct ink writing of LCE inks is used to align their mesogen domains along the direction of the print path. To demonstrate the power of this additive manufacturing approach, shape-morphing LCEA architectures are fabricated, which undergo reversible planar-to-3D and 3D-to-3D' transformations on demand, that can lift significantly more weight than other LCEAs reported to date. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Specific and reversible DNA-directed self-assembly of oil-in-water emulsion droplets

    PubMed Central

    Hadorn, Maik; Boenzli, Eva; Sørensen, Kristian T.; Fellermann, Harold; Eggenberger Hotz, Peter; Hanczyc, Martin M.

    2012-01-01

    Higher-order structures that originate from the specific and reversible DNA-directed self-assembly of microscopic building blocks hold great promise for future technologies. Here, we functionalized biotinylated soft colloid oil-in-water emulsion droplets with biotinylated single-stranded DNA oligonucleotides using streptavidin as an intermediary linker. We show the components of this modular linking system to be stable and to induce sequence-specific aggregation of binary mixtures of emulsion droplets. Three length scales were thereby involved: nanoscale DNA base pairing linking microscopic building blocks resulted in macroscopic aggregates visible to the naked eye. The aggregation process was reversible by changing the temperature and electrolyte concentration and by the addition of competing oligonucleotides. The system was reset and reused by subsequent refunctionalization of the emulsion droplets. DNA-directed self-assembly of oil-in-water emulsion droplets, therefore, offers a solid basis for programmable and recyclable soft materials that undergo structural rearrangements on demand and that range in application from information technology to medicine. PMID:23175791

  11. The surface properties of Shewanella putrefaciens 200 and S. oneidensis MR-1: the effect of pH and terminal electron acceptors.

    PubMed

    Furukawa, Yoko; Dale, Jason R

    2013-04-08

    We investigated the surface characteristics of two strains of Shewanella sp., S. oneidensis MR-1 and S. putrefaciens 200, that were grown under aerobic conditions as well as under anaerobic conditions with trimethylamine oxide (TMAO) as the electron acceptor. The investigation focused on the experimental determination of electrophoretic mobility (EPM) under a range of pH and ionic strength, as well as by subsequent modeling in which Shewanella cells were considered to be soft particles with water- and ion-permeable outermost layers. The soft layer of p200 is significantly more highly charged (i.e., more negative) than that of MR-1. The effect of electron acceptor on the soft particle characteristics of Shewanella sp. is complex. The fixed charge density, which is a measure of the deionized and deprotonated functional groups in the soft layer polymers, is slightly greater (i.e., more negative) for aerobically grown p200 than for p200 grown with TMAO. On the other hand, the fixed charge density of aerobically grown MR1 is slightly less than that of p200 grown with TMAO. The effect of pH on the soft particle characteristics is also complex, and does not exhibit a clear pH-dependent trend. The Shewanella surface characteristics were attributed to the nature of the outermost soft layer, the extracellular polymeric substances (EPS) in case of p200 and lypopolysaccharides (LPS) in case of MR1 which generally lacks EPS. The growth conditions (i.e., aerobic vs. anaerobic TMAO) have an influence on the soft layer characteristics of Shewanella sp. cells. Meanwhile, the clear pH dependency of the mechanical and morphological characteristics of EPS and LPS layers, observed in previous studies through atomic force microscopy, adhesion tests and spectroscopies, cannot be corroborated by the electrohydrodynamics-based soft particle characteristics which does not exhibited a clear pH dependency in this study. While the electrohydrodynamics-based soft-particle model is a useful tool in understanding bacteria's surface properties, it needs to be supplemented with other characterization methods and models (e.g., chemical and micromechanical) in order to comprehensively address all of the surface-related characteristics important in environmental and other aqueous processes.

  12. A general perspective on the magnetization reversal in cylindrical soft magnetic nanowires with dominant shape anisotropy

    NASA Astrophysics Data System (ADS)

    Kuncser, A.; Antohe, S.; Kuncser, V.

    2017-02-01

    Peculiarities of the magnetization reversal process in cylindrical Ni-Cu soft magnetic nanowires with dominant shape anisotropy are analyzed via both static and time dependent micromagnetic simulations. A reversible process involving a coherent-like spin rotation is always observed for magnetic fields applied perpendicularly to the easy axis whereas nucleation of domain walls is introduced for fields applied along the easy axis. Simple criteria for making distinction between a Stoner-Wohlfarth type rotation and a nucleation mechanism in systems with uniaxial magnetic anisotropy are discussed. Superposed reversal mechanisms can be in action for magnetic fields applied at arbitrary angles with respect to the easy axis within the condition of an enough strong axial component required by the nucleation. The dynamics of the domain wall, involving two different stages (nucleation and propagation), is discussed with respect to initial computing conditions and orientations of the magnetic field. A nucleation time of about 3 ns and corkscrew domain walls propagating with a constant velocity of about 150 m/s are obtained in case of Ni-Cu alloy (Ni rich side) NWs with diameters of 40 nm and high aspect ratio.

  13. Magnetic Yoking and Tunable Interactions in FePt-Based Hard/Soft Bilayers

    PubMed Central

    Gilbert, Dustin A.; Liao, Jung-Wei; Kirby, Brian J.; Winklhofer, Michael; Lai, Chih-Huang; Liu, Kai

    2016-01-01

    Magnetic interactions in magnetic nanostructures are critical to nanomagnetic and spintronic explorations. Here we demonstrate an extremely sensitive magnetic yoking effect and tunable interactions in FePt based hard/soft bilayers mediated by the soft layer. Below the exchange length, a thin soft layer strongly exchange couples to the perpendicular moments of the hard layer; above the exchange length, just a few nanometers thicker, the soft layer moments turn in-plane and act to yoke the dipolar fields from the adjacent hard layer perpendicular domains. The evolution from exchange to dipolar-dominated interactions is experimentally captured by first-order reversal curves, the ΔM method, and polarized neutron reflectometry, and confirmed by micromagnetic simulations. These findings demonstrate an effective yoking approach to design and control magnetic interactions in wide varieties of magnetic nanostructures and devices. PMID:27604428

  14. Buckling of Elastomeric Beams Enables Actuation of Soft Machines

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

    Yang, Dian; Mosadegh, Bobak; Ainla, Alar

    2015-09-21

    Soft, pneumatic actuators that buckle when interior pressure is less than exterior provide a new mechanism of actuation. Upon application of negative pneumatic pressure, elastic beam elements in these actuators undergo reversible, cooperative collapse, and generate a rotational motion. These actuators are inexpensive to fabricate, lightweight, easy to control, and safe to operate. They can be used in devices that manipulate objects, locomote, or interact cooperatively with humans.

  15. Influence of the properties of soft collective spin wave modes on the magnetization reversal in finite arrays of dipolarly coupled magnetic dots

    NASA Astrophysics Data System (ADS)

    Stebliy, Maxim; Ognev, Alexey; Samardak, Alexander; Chebotkevich, Ludmila; Verba, Roman; Melkov, Gennadiy; Tiberkevich, Vasil; Slavin, Andrei

    2015-06-01

    Magnetization reversal in finite chains and square arrays of closely packed cylindrical magnetic dots, having vortex ground state in the absence of the external bias field, has been studied experimentally by measuring static hysteresis loops, and also analyzed theoretically. It has been shown that the field Bn of a vortex nucleation in a dot as a function of the finite number N of dots in the array's side may exhibit a monotonic or an oscillatory behavior depending on the array geometry and the direction of the external bias magnetic field. The oscillations in the dependence Bn(N) are shown to be caused by the quantization of the collective soft spin wave mode, which corresponds to the vortex nucleation in a finite array of dots. These oscillations are directly related to the form and symmetry of the dispersion law of the soft SW mode: the oscillation could appear only if the minimum of the soft mode spectrum is not located at any of the symmetric points inside the first Brillouin zone of the array's lattice. Thus, the purely static measurements of the hysteresis loops in finite arrays of coupled magnetic dots can yield important information about the properties of the collective spin wave excitations in these arrays.

  16. Properties and Degradation of Polarization Reversal of Soft BaTiO3 Ceramics for Ferroelectric Thin-Film Devices

    NASA Astrophysics Data System (ADS)

    Thongrueng, Jirawat; Tsuchiya, Toshio; Masuda, Yoichiro; Fujita, Shigetaka; Nagata, Kunihiro

    1999-09-01

    Soft BaTiO3 ceramics having a very low coercive field of 65 V/mm were prepared by substituting 9 mol% Hf Zr for the Ti-site of BaTiO3, for applications to ferroelectric thin-film devices. Electrical properties of the soft BaTiO3 ceramics were measured and compared with those of normal BaTiO3 ceramics. By substituting Hf Zr for Ti-site, the phase transition temperatures were controlled, and we could select the preferred crystal structure from the tetragonal, orthorhombic and rhombohedral phases at room temperature. In addition, the preparation and characterization of the soft BaTiO3 thin-films using a sol-gel process were carried out.

  17. Effect of hydralazine on duration of soft tissue local anesthesia following dental treatment: a randomized clinical trial.

    PubMed

    Fakheran Esfahani, Omid; Pouraboutaleb, Mohammad Fazel; Khorami, Behnam

    2015-01-01

    Prolonged numbness following routine dental treatments can cause difficulties in speaking and swallowing and may result in inadvertent biting of soft tissues. Local injection of vasodilator agents may represent a solution to this problem. The aim of this study was to evaluate the effect of submucosal injection of hydralazine hydrochloride (HCl) on the duration of oral soft tissue anesthesia after routine dental treatment. This randomized, single-blinded, controlled clinical trial included 50 patients who received inferior alveolar nerve block (2% lidocaine with 1:100,000 epinephrine) for simple restorative treatment. Upon completion of the dental treatment, patients randomly received a hydralazine HCl or sham injection in the same site as the local anesthetic injection. The reversal time to normal sensation of soft tissues (lips, tongue, and perioral skin) was evaluated and reported every 5 minutes by the patients, who followed an assessment protocol that they were taught in advance of treatment. Median recovery times in the hydralazine group and the sham group were 81.4 (SD, 3.6) and 221.8 (SD, 6.3) minutes, respectively. Based on Kaplan-Meier survival analysis, the duration of soft tissue anesthesia in the 2 groups was significantly different (P < 0.0001). By 1 hour after the reversal injection, 76% of subjects receiving hydralazine HCl had returned to normal intraoral and perioral sensation, but none of the subjects in the sham group reported normal sensation. Based on these results, submucosal injection of hydralazine HCl can be considered a safe and effective method to reduce the duration of local anesthetic-induced soft tissue numbness and the related functional problems.

  18. A Soft Gripper with Rigidity Tunable Elastomer Strips as Ligaments.

    PubMed

    Nasab, Amir Mohammadi; Sabzehzar, Amin; Tatari, Milad; Majidi, Carmel; Shan, Wanliang

    2017-12-01

    Like their natural counterparts, soft bioinspired robots capable of actively tuning their mechanical rigidity can rapidly transition between a broad range of motor tasks-from lifting heavy loads to dexterous manipulation of delicate objects. Reversible rigidity tuning also enables soft robot actuators to reroute their internal loading and alter their mode of deformation in response to intrinsic activation. In this study, we demonstrate this principle with a three-fingered pneumatic gripper that contains "programmable" ligaments that change stiffness when activated with electrical current. The ligaments are composed of a conductive, thermoplastic elastomer composite that reversibly softens under resistive heating. Depending on which ligaments are activated, the gripper will bend inward to pick up an object, bend laterally to twist it, and bend outward to release it. All of the gripper motions are generated with a single pneumatic source of pressure. An activation-deactivation cycle can be completed within 15 s. The ability to incorporate electrically programmable ligaments in a pneumatic or hydraulic actuator has the potential to enhance versatility and reduce dependency on tubing and valves.

  19. miR-199a-5p regulates HIF-1α and OSGIN2 and its expression is correlated to soft-tissue sarcoma patients' outcome

    PubMed Central

    Keßler, Jacqueline; Rot, Swetlana; Bache, Matthias; Kappler, Matthias; Würl, Peter; Vordermark, Dirk; Taubert, Helge; Greither, Thomas

    2016-01-01

    Soft tissue sarcomas are a heterogeneous group of malignant neoplasms of mesenchymal origin. Partly due to hypoxia, an aggressive and radioresistant phenotype frequently develops, resulting in poorer patient outcome. microRNAs (miRNAs) are tiny, non-coding regulators of gene expression and in situations of cellular stress situations may predict clinical progression and patient outcome. In the present study, hypoxia-associated miR-199a-5p expression in 96 soft tissue sarcoma samples was analysed by reverse transcription-quantitative polymerase chain reaction and associations between miR-199a-5p expression and patient clinicopathological characteristics and survival were measured. Additionally, luciferase reporter assays analyzed the post-transcriptional regulation of hypoxia-associated genes hypoxia-inducible factor 1α (HIF-1α), oxidative stress induced growth inhibitor 2 (OSGIN2) and vascular endothelial growth factor (VEGF) by miR-199a-5p. Survival analyses indicated that low expression of miR-199a-5p was significantly correlated with poorer tumor-specific survival (univariate Cox's-Regression analyses; relative risk=1.92, P=0.029). Furthermore, it was demonstrated that the 3′UTR of HIF-1α and OSGIN2 genes were regulated by miR-199a-5p in-vitro, although the 3′UTR of VEGF was not. To the best of our knowledge, this is the first report demonstrating the regulation of the 3′untranslated region of the OSGIN2 gene by miR-199a-5p and a significant correlation between low miR-199a-5p expression and a poor outcome of patients with soft tissue sarcoma. PMID:28101243

  20. Effects of therapy on masseter activity and chewing kinematics in patients with unilateral posterior crossbite.

    PubMed

    Piancino, Maria Grazia; Falla, Deborah; Merlo, Andrea; Vallelonga, Teresa; de Biase, Corrado; Dalessandri, Domenico; Debernardi, Cesare

    2016-07-01

    To describe the effects of therapy on masseter activity and chewing kinematic in patients with unilateral posterior crossbite (UPC). Fifty children (age: mean ± SD: 9.1 ± 2.3 years) with UPC (34 on the right side, 16 on the left side) and twenty children (age: 9.5 ± 2.6 years) with normal occlusion were selected for the study. The mandibular motion and the muscular activity during chewing soft and hard boli were simultaneously recorded, before and after correction with function generating bite, after a mean treatment time of 7.3 ± 2.4 months plus the retention time of 5-6 months. The percentage of reverse cycles and the percent difference between ipsilateral and contralateral peaks of the masseter electromyography envelopes were computed. Before therapy, the percentage of reverse cycles during chewing on the crossbite side was greater in patients than in controls (P<0.001) and significantly reduced after therapy (P<0.001) towards the reference normal value (soft bolus; pre: 57 ± 30%, post:12 ± 17%; hard bolus; pre: 65 ± 34%, post: 12 ± 13%; reference value: soft bolus 4 ± 2%, hard bolus 5 ± 3%). Before therapy the percent difference between electromyography envelope peaks in patients was lower than in controls (P<0.01) and significantly increased after therapy (P<0.05) becoming similar to the reference normal value. The correction induced a normal-like coordination of masseter muscles activity together with a significant reduction of the reverse chewing patterns. The previous altered muscular activation corresponded to the altered kinematics of reverse chewing cycles that might be considered a useful indicator of the severity of the masticatory function involvement. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Study of the dependence of direct soft photon production on the jet characteristics in hadronic Z 0 decays

    NASA Astrophysics Data System (ADS)

    Abdallah, J.; Abreu, P.; Adam, W.; Adzic, P.; Albrecht, T.; Alemany-Fernandez, R.; Allmendinger, T.; Allport, P. P.; Amaldi, U.; Amapane, N.; Amato, S.; Anashkin, E.; Andreazza, A.; Andringa, S.; Anjos, N.; Antilogus, P.; Apel, W.-D.; Arnoud, Y.; Ask, S.; Asman, B.; Augustin, J. E.; Augustinus, A.; Baillon, P.; Ballestrero, A.; Bambade, P.; Barbier, R.; Bardin, D.; Barker, G. J.; Baroncelli, A.; Battaglia, M.; Baubillier, M.; Becks, K.-H.; Begalli, M.; Behrmann, A.; Ben-Haim, E.; Benekos, N.; Benvenuti, A.; Berat, C.; Berggren, M.; Bertrand, D.; Besancon, M.; Besson, N.; Bloch, D.; Blom, M.; Bluj, M.; Bonesini, M.; Boonekamp, M.; Booth, P. S. L.; Borisov, G.; Botner, O.; Bouquet, B.; Bowcock, T. J. V.; Boyko, I.; Bracko, M.; Brenner, R.; Brodet, E.; Bruckman, P.; Brunet, J. M.; Buschbeck, B.; Buschmann, P.; Calvi, M.; Camporesi, T.; Canale, V.; Carena, F.; Castro, N.; Cavallo, F.; Chapkin, M.; Charpentier, Ph.; Checchia, P.; Chierici, R.; Chliapnikov, P.; Chudoba, J.; Chung, S. U.; Cieslik, K.; Collins, P.; Contri, R.; Cosme, G.; Cossutti, F.; Costa, M. J.; Crennell, D.; Cuevas, J.; D'Hondt, J.; da Silva, T.; da Silva, W.; Della Ricca, G.; de Angelis, A.; de Boer, W.; de Clercq, C.; de Lotto, B.; de Maria, N.; de Min, A.; de Paula, L.; di Ciaccio, L.; di Simone, A.; Doroba, K.; Drees, J.; Eigen, G.; Ekelof, T.; Ellert, M.; Elsing, M.; Espirito Santo, M. C.; Fanourakis, G.; Fassouliotis, D.; Feindt, M.; Fernandez, J.; Ferrer, A.; Ferro, F.; Flagmeyer, U.; Foeth, H.; Fokitis, E.; Fulda-Quenzer, F.; Fuster, J.; Gandelman, M.; Garcia, C.; Gavillet, Ph.; Gazis, E.; Gokieli, R.; Golob, B.; Gomez-Ceballos, G.; Goncalves, P.; Graziani, E.; Grosdidier, G.; Grzelak, K.; Guy, J.; Haag, C.; Hallgren, A.; Hamacher, K.; Hamilton, K.; Haug, S.; Hauler, F.; Hedberg, V.; Hennecke, M.; Hoffman, J.; Holmgren, S.-O.; Holt, P. J.; Houlden, M. A.; Jackson, J. N.; Jarlskog, G.; Jarry, P.; Jeans, D.; Johansson, E. K.; Jonsson, P.; Joram, C.; Jungermann, L.; Kapusta, F.; Katsanevas, S.; Katsoufis, E.; Kernel, G.; Kersevan, B. P.; Kerzel, U.; King, B. T.; Kjaer, N. J.; Kluit, P.; Kokkinias, P.; Kourkoumelis, C.; Kouznetsov, O.; Krumstein, Z.; Kucharczyk, M.; Lamsa, J.; Leder, G.; Ledroit, F.; Leinonen, L.; Leitner, R.; Lemonne, J.; Lepeltier, V.; Lesiak, T.; Liebig, W.; Liko, D.; Lipniacka, A.; Lopes, J. H.; Lopez, J. M.; Loukas, D.; Lutz, P.; Lyons, L.; MacNaughton, J.; Malek, A.; Maltezos, S.; Mandl, F.; Marco, J.; Marco, R.; Marechal, B.; Margoni, M.; Marin, J.-C.; Mariotti, C.; Markou, A.; Martinez-Rivero, C.; Masik, J.; Mastroyiannopoulos, N.; Matorras, F.; Matteuzzi, C.; Mazzucato, F.; Mazzucato, M.; Mc Nulty, R.; Meroni, C.; Migliore, E.; Mitaroff, W.; Mjoernmark, U.; Moa, T.; Moch, M.; Moenig, K.; Monge, R.; Montenegro, J.; Moraes, D.; Moreno, S.; Morettini, P.; Mueller, U.; Muenich, K.; Mulders, M.; Mundim, L.; Murray, W.; Muryn, B.; Myatt, G.; Myklebust, T.; Nassiakou, M.; Navarria, F.; Nawrocki, K.; Nemecek, S.; Nicolaidou, R.; Nikolenko, M.; Oblakowska-Mucha, A.; Obraztsov, V.; Olshevski, A.; Onofre, A.; Orava, R.; Osterberg, K.; Ouraou, A.; Oyanguren, A.; Paganoni, M.; Paiano, S.; Palacios, J. P.; Palka, H.; Papadopoulou, Th. D.; Pape, L.; Parkes, C.; Parodi, F.; Parzefall, U.; Passeri, A.; Passon, O.; Peralta, L.; Perepelitsa, V.; Perrotta, A.; Petrolini, A.; Piedra, J.; Pieri, L.; Pierre, F.; Pimenta, M.; Piotto, E.; Podobnik, T.; Poireau, V.; Pol, M. E.; Polok, G.; Pozdniakov, V.; Pukhaeva, N.; Pullia, A.; Radojicic, D.; Rebecchi, P.; Rehn, J.; Reid, D.; Reinhardt, R.; Renton, P.; Richard, F.; Ridky, J.; Rivero, M.; Rodriguez, D.; Romero, A.; Ronchese, P.; Roudeau, P.; Rovelli, T.; Ruhlmann-Kleider, V.; Ryabtchikov, D.; Sadovsky, A.; Salmi, L.; Salt, J.; Sander, C.; Savoy-Navarro, A.; Schwickerath, U.; Sekulin, R.; Siebel, M.; Sisakian, A.; Smadja, G.; Smirnova, O.; Sokolov, A.; Sopczak, A.; Sosnowski, R.; Spassov, T.; Stanitzki, M.; Stocchi, A.; Strauss, J.; Stugu, B.; Szczekowski, M.; Szeptycka, M.; Szumlak, T.; Tabarelli, T.; Tegenfeldt, F.; Timmermans, J.; Tkatchev, L.; Tobin, M.; Todorovova, S.; Tome, B.; Tonazzo, A.; Tortosa, P.; Travnicek, P.; Treille, D.; Tristram, G.; Trochimczuk, M.; Troncon, C.; Turluer, M.-L.; Tyapkin, I. A.; Tyapkin, P.; Tzamarias, S.; Uvarov, V.; Valenti, G.; van Dam, P.; van Eldik, J.; van Remortel, N.; van Vulpen, I.; Vegni, G.; Veloso, F.; Venus, W.; Verdier, P.; Verzi, V.; Vilanova, D.; Vitale, L.; Vrba, V.; Wahlen, H.; Washbrook, A. J.; Weiser, C.; Wicke, D.; Wickens, J.; Wilkinson, G.; Winter, M.; Witek, M.; Yushchenko, O.; Zalewska, A.; Zalewski, P.; Zavrtanik, D.; Zhuravlov, V.; Zimin, N. I.; Zintchenko, A.; Zupan, M.; DELPHI Collaboration

    2010-06-01

    An analysis of the direct soft photon production rate as a function of the parent jet characteristics is presented, based on hadronic events collected by the DELPHI experiment at LEP1. The dependences of the photon rates on the jet kinematic characteristics (momentum, mass, etc.) and on the jet charged, neutral and total hadron multiplicities are reported. Up to a scale factor of about four, which characterizes the overall value of the soft photon excess, a similarity of the observed soft photon behavior to that of the inner hadronic bremsstrahlung predictions is found for the momentum, mass, and jet charged multiplicity dependences. However for the dependence of the soft photon rate on the jet neutral and total hadron multiplicities a prominent difference is found for the observed soft photon signal as compared to the expected bremsstrahlung from final state hadrons. The observed linear increase of the soft photon production rate with the jet total hadron multiplicity and its strong dependence on the jet neutral multiplicity suggest that the rate is proportional to the number of quark pairs produced in the fragmentation process, with the neutral pairs being more effectively radiating than the charged ones.

  2. Analysis of Soft Error Rates in 65- and 28-nm FD-SOI Processes Depending on BOX Region Thickness and Body Bias by Monte-Carlo Based Simulations

    NASA Astrophysics Data System (ADS)

    Zhang, Kuiyuan; Umehara, Shigehiro; Yamaguchi, Junki; Furuta, Jun; Kobayashi, Kazutoshi

    2016-08-01

    This paper analyzes how body bias and BOX region thickness affect soft error rates in 65-nm SOTB (Silicon on Thin BOX) and 28-nm UTBB (Ultra Thin Body and BOX) FD-SOI processes. Soft errors are induced by alpha-particle and neutron irradiation and the results are then analyzed by Monte Carlo based simulation using PHITS-TCAD. The alpha-particle-induced single event upset (SEU) cross-section and neutron-induced soft error rate (SER) obtained by simulation are consistent with measurement results. We clarify that SERs decreased in response to an increase in the BOX thickness for SOTB while SERs in UTBB are independent of BOX thickness. We also discover SOTB develops a higher tolerance to soft errors when reverse body bias is applied while UTBB become more susceptible.

  3. Effect of magnetic soft phase on the magnetic properties of bulk anisotropic Nd2Fe14B/α-Fe nanocomposite permanent magnets

    NASA Astrophysics Data System (ADS)

    Li, Yuqing; Yue, Ming; Zhao, Guoping; Zhang, Hongguo

    2018-01-01

    The effects of soft phase with different particle sizes and distributions on the Nd2Fe14B/α-Fe nanocomposite magnets have been studied by the micro-magnetism simulation. The calculated results show that smaller and/or scattered distribution of soft phase can benefit to the coercivity (H ci) of the nanocomposite magnets. The magnetization moment evolution during magnetic reversal is systematically analyzed. On the other hand, magnetic properties of anisotropic Nd-Fe-B/α-Fe nanocomposite magnets prepared by hot pressing and hot deformation methods also provide evidences for the calculated results.

  4. Reversal of caffeine withdrawal by ingestion of a soft beverage.

    PubMed

    Watson, J M; Lunt, M J; Morris, S; Weiss, M J; Hussey, D; Kerr, D

    2000-05-01

    Followlng regular use, acute cessation of caffeine is associated with a characteristic withdrawal syndrome. Despite this, caffeine remains popular with its consumers. The aim of this study was to examine the physiologic and psychologic effects of small caffeine doses, administered in the form of a market-leading soft drink, on healthy women who were acutely withdrawn from caffeine. After 48-h abstinence and overnight fast, 11 healthy (22 to 40 years) female volunteers, all regular caffeine users (daily consumption 143 to 773 mg) consumed using a double-blind. randomized, controlled cross-over design either 2 tins of regular or caffeine-free Diet Coke. On both visits a Mars bar was eaten to prevent hypoglycaemia. Thus, the caffeine load was 76 or 10 mg respectively. Following ingestion of regular Diet Coke, there was a l0% fall in middle cerebral artery velocity (95% CI [6%-l4%], p < 0.005 versus caffeine free) and improvement in feelings of pleasure (p < 0.046) and energy (p < 0.037). Intellectual function (4-choice reaction time) was unaffected by caffeine status. On both visits, ingestion of Diet Coke induced a pressor response (maximum rise in systolic pressure +15+/- 2 mm Hg with caffeine and +l2 +/- 2 mm Hg with caffeine-free beverage, both p < 0.001 compared with baseline). In conclusion, in women acutely withdrawn from caffeine, ingestion of a popular soft beverage containing modest amounts of caffeine is associated with demonstrable physiologic and psychologic effects.

  5. Nickel-hydrogen cell reversal characteristics

    NASA Technical Reports Server (NTRS)

    Lurie, Charles

    1994-01-01

    Nickel-hydrogen cell reversal characteristics are being studied as part of a TRW program directed towards development of a high current battery cell bypass switch. The following are discussed: cell bypass switch; nickel-hydrogen cell reversal characteristics; and nickel-hydrogen cell chemistry: discharge/reversal and overdischarge (reversal) with nickel and hydrogen precharge.

  6. Soft-matter composites with electrically tunable elastic rigidity

    NASA Astrophysics Data System (ADS)

    Shan, Wanliang; Lu, Tong; Majidi, Carmel

    2013-08-01

    We use a phase-changing metal alloy to reversibly tune the elastic rigidity of an elastomer composite. The elastomer is embedded with a sheet of low-melting-point Field’s metal and an electric Joule heater composed of a serpentine channel of liquid-phase gallium-indium-tin (Galinstan®) alloy. At room temperature, the embedded Field’s metal is solid and the composite remains elastically rigid. Joule heating causes the Field’s metal to melt and allows the surrounding elastomer to freely stretch and bend. Using a tensile testing machine, we measure that the effective elastic modulus of the composite reversibly changes by four orders of magnitude when powered on and off. This dramatic change in rigidity is accurately predicted with a model for an elastic composite. Reversible rigidity control is also accomplished by replacing the Field’s metal with shape memory polymer. In addition to demonstrating electrically tunable rigidity with an elastomer, we also introduce a new technique to rapidly produce soft-matter electronics and multifunctional materials in several minutes with laser-patterned adhesive film and masked deposition of liquid-phase metal alloy.

  7. Hungry for solutions

    NASA Astrophysics Data System (ADS)

    MacPhee, Cait

    2016-11-01

    As obesity rates continue to rise in many parts of the world, Cait MacPhee explains how soft-matter physicists could help reverse the trend by crafting “functional” foods that promote feelings of fullness and satisfaction

  8. Atomic resolution of structural changes in elastic crystals of copper(II) acetylacetonate

    NASA Astrophysics Data System (ADS)

    Worthy, Anna; Grosjean, Arnaud; Pfrunder, Michael C.; Xu, Yanan; Yan, Cheng; Edwards, Grant; Clegg, Jack K.; McMurtrie, John C.

    2018-01-01

    Single crystals are typically brittle, inelastic materials. Such mechanical responses limit their use in practical applications, particularly in flexible electronics and optical devices. Here we describe single crystals of a well-known coordination compound—copper(II) acetylacetonate—that are flexible enough to be reversibly tied into a knot. Mechanical measurements indicate that the crystals exhibit an elasticity similar to that of soft materials such as nylon, and thus display properties normally associated with both hard and soft matter. Using microfocused synchrotron radiation, we mapped the changes in crystal structure that occur on bending, and determined the mechanism that allows this flexibility with atomic precision. We show that, under strain, the molecules in the crystal reversibly rotate, and thus reorganize to allow the mechanical compression and expansion required for elasticity and still maintain the integrity of the crystal structure.

  9. Concept for a 3D-printed soft rotary actuator driven by a shape-memory alloy

    NASA Astrophysics Data System (ADS)

    Yuan, Han; Chapelle, Frédéric; Fauroux, Jean-Christophe; Balandraud, Xavier

    2018-05-01

    In line with the recent development of soft actuators involving shape-memory alloys (SMAs) embedded in compliant structures, this paper proposes a concept for a rotary actuator driven by a SMA wire placed inside a 3D-printed helical structure. The concept consists of using the one-way memory effect of the SMA (activated by Joule heating) to create the rotation of a material point of the structure, while the inverse rotation is obtained during the return to ambient temperature thanks to the structure’s elasticity. The study was performed in three steps. First, a prototype was designed from a chain of design rules, and tested to validate the feasibility of the concept. Thermal and geometrical measurements were performed using infrared and visible-range stereo cameras. A clockwise rotation (250°) followed by an anti-clockwise rotation (‑200°) were obtained, enabling us to validate the concept despite the partial reversibility of the movement. Second, finite element simulations were performed to improve rotation reversibility. The high compliance of the mechanical system required a framework of large displacements for the calculations (in the strength of materials sense), due to the high structural flexibility. Finally, a second prototype was constructed and tested. Attention was paid to the rotation (fully reversible rotation of 150° reached) as well as to parasitic movements due to overall structural deformation. This study opens new prospects for the design and analysis of 3D-printed soft actuators activated by smart materials.

  10. Effects of protein-coated nanofibers on conformation of gingival fibroblast spheroids: potential utility for connective tissue regeneration.

    PubMed

    Kaufman, Gili; Whitescarver, Ryan A; Nunes, Laiz; Palmer, Xavier-Lewis; Skrtic, Drago; Tutak, Wojtek

    2018-01-24

    Deep wounds in the gingiva caused by trauma or surgery require a rapid and robust healing of connective tissues. We propose utilizing gas-brushed nanofibers coated with collagen and fibrin for that purpose. Our hypotheses are that protein-coated nanofibers will: (i) attract and mobilize cells in various spatial orientations, and (ii) regulate the expression levels of specific extracellular matrix (ECM)-associated proteins, determining the initial conformational nature of dense and soft connective tissues. Gingival fibroblast monolayers and 3D spheroids were cultured on ECM substrate and covered with gas-blown poly-(DL-lactide-co-glycolide) (PLGA) nanofibers (uncoated/coated with collagen and fibrin). Cell attraction and rearrangement was followed by F-actin staining and confocal microscopy. Thicknesses of the cell layers, developed within the nanofibers, were quantified by ImageJ software. The expression of collagen1α1 chain (Col1α1), fibronectin, and metalloproteinase 2 (MMP2) encoding genes was determined by quantitative reverse transcription analysis. Collagen- and fibrin- coated nanofibers induced cell migration toward fibers and supported cellular growth within the scaffolds. Both proteins affected the spatial rearrangement of fibroblasts by favoring packed cell clusters or intermittent cell spreading. These cell arrangements resembled the structural characteristic of dense and soft connective tissues, respectively. Within three days of incubation, fibroblast spheroids interacted with the fibers, and grew robustly by increasing their thickness compared to monolayers. While the ECM key components, such as fibronectin and MMP2 encoding genes, were expressed in both protein groups, Col1α1 was predominantly expressed in bundled fibroblasts grown on collagen fibers. This enhanced expression of collagen1 is typical for dense connective tissue. Based on results of this study, our gas-blown, collagen- and fibrin-coated PLGA nanofibers are viable candidates for engineering soft and dense connective tissues with the required structural characteristics and functions needed for wound healing applications. Rapid regeneration of these layers should enhance healing of open wounds in a harsh oral environment.

  11. Physical characteristics of indigestible solids affect emptying from the fasting human stomach.

    PubMed Central

    Meyer, B; Beglinger, C; Neumayer, M; Stalder, G A

    1989-01-01

    Gastric emptying of indigestible solids depends on their size. It is not clear whether physical characteristics other than particle size affect emptying of indigestible solids from the fasting human stomach. We studied gastric emptying of three differently shaped particles, (cubes, spheres, rods) of either hard or soft consistency during the fasting state in human volunteers. The shape of indigestible particles did not affect their emptying. The area under the gastric emptying curve (AUC: particles x hour) was for hard cubes 24.7 (2.2), for hard spheres 27.9 (1.6), for hard rods 26.9 (2.7). All soft particles emptied faster than their identically shaped hard counterparts, but there was no difference among the three shapes (AUC for soft cubes: 29.2 (3.0), for soft spheres 32.0 (1.8), for soft rods 34.1 (1.2). If gastric emptying of hard and soft particles was compared independently of their shape, soft particles emptied significantly faster than hard ones: AUC 31.8 (1.2) v 26.5 (1.3) (p less than 0.01). In conclusion, the consistency but not the shape significantly affects gastric emptying. Specific physical characteristics other than size and shape may affect gastric emptying of indigestible particles which may be of importance in the design of drugs. PMID:2599438

  12. Can soft biometric traits assist user recognition?

    NASA Astrophysics Data System (ADS)

    Jain, Anil K.; Dass, Sarat C.; Nandakumar, Karthik

    2004-08-01

    Biometrics is rapidly gaining acceptance as the technology that can meet the ever increasing need for security in critical applications. Biometric systems automatically recognize individuals based on their physiological and behavioral characteristics. Hence, the fundamental requirement of any biometric recognition system is a human trait having several desirable properties like universality, distinctiveness, permanence, collectability, acceptability, and resistance to circumvention. However, a human characteristic that possesses all these properties has not yet been identified. As a result, none of the existing biometric systems provide perfect recognition and there is a scope for improving the performance of these systems. Although characteristics like gender, ethnicity, age, height, weight and eye color are not unique and reliable, they provide some information about the user. We refer to these characteristics as "soft" biometric traits and argue that these traits can complement the identity information provided by the primary biometric identifiers like fingerprint and face. This paper presents the motivation for utilizing soft biometric information and analyzes how the soft biometric traits can be automatically extracted and incorporated in the decision making process of the primary biometric system. Preliminary experiments were conducted on a fingerprint database of 160 users by synthetically generating soft biometric traits like gender, ethnicity, and height based on known statistics. The results show that the use of additional soft biometric user information significantly improves (approximately 6%) the recognition performance of the fingerprint biometric system.

  13. Waxy soft white wheat: extrusion characteristics and thermal and rheological properties

    USDA-ARS?s Scientific Manuscript database

    Waxy wheat flour was analyzed for its thermal and rheological properties and extruded to understand its processing characteristics. Comparisons were made with normal soft white wheat flour to identify extrusion differences under the same conditions. The thermal and rheological properties through Rap...

  14. Unsteady penetration of a target by a liquid jet

    PubMed Central

    Uth, Tobias; Deshpande, Vikram S.

    2013-01-01

    It is widely acknowledged that ceramic armor experiences an unsteady penetration response: an impacting projectile may erode on the surface of a ceramic target without substantial penetration for a significant amount of time and then suddenly start to penetrate the target. Although known for more than four decades, this phenomenon, commonly referred to as dwell, remains largely unexplained. Here, we use scaled analog experiments with a low-speed water jet and a soft, translucent target material to investigate dwell. The transient target response, in terms of depth of penetration and impact force, is captured using a high-speed camera in combination with a piezoelectric force sensor. We observe the phenomenon of dwell using a soft (noncracking) target material. The results show that the penetration rate increases when the flow of the impacting water jet is reversed due to the deformation of the jet–target interface––this reversal is also associated with an increase in the force exerted by the jet on the target. Creep penetration experiments with a constant indentation force did not show an increase in the penetration rate, confirming that flow reversal is the cause of the unsteady penetration rate. Our results suggest that dwell can occur in a ductile noncracking target due to flow reversal. This phenomenon of flow reversal is rather widespread and present in a wide range of impact situations, including water-jet cutting, needleless injection, and deposit removal via a fluid jet. PMID:24277818

  15. Quality characteristics of U.S. soft white and club wheat

    USDA-ARS?s Scientific Manuscript database

    U.S. soft white wheat from the Pacific Northwest states of Washington, Oregon and Idaho is a premium quality, versatile soft wheat. Soft White wheat (SWW) is comprised of winter and spring-sown varieties; spike morphology further delineates the class into ‘common’ (lax) and club sub-classes. The reg...

  16. Soft-tissue facial characteristics of attractive Chinese men compared to normal men.

    PubMed

    Wu, Feng; Li, Junfang; He, Hong; Huang, Na; Tang, Youchao; Wang, Yuanqing

    2015-01-01

    To compare the facial characteristics of attractive Chinese men with those of reference men. The three-dimensional coordinates of 50 facial landmarks were collected in 40 healthy reference men and in 40 "attractive" men, soft tissue facial angles, distances, areas, and volumes were computed and compared using analysis of variance. When compared with reference men, attractive men shared several similar facial characteristics: relatively large forehead, reduced mandible, and rounded face. They had a more acute soft tissue profile, an increased upper facial width and middle facial depth, larger mouth, and more voluminous lips than reference men. Attractive men had several facial characteristics suggesting babyness. Nonetheless, each group of men was characterized by a different development of these features. Esthetic reference values can be a useful tool for clinicians, but should always consider the characteristics of individual faces.

  17. Distally based saphenous neurocutaneous perforator flap combined with vac therapy for soft tissue reconstruction and hardware salvage in the lower extremities.

    PubMed

    Wen, Gen; Wang, Chun-Yang; Chai, Yi-Min; Cheng, Liang; Chen, Ming; Yi-Min, L V

    2013-11-01

    The complex wound with the exposed hardware and infection is one of the common complications after the internal fixation of the tibia fracture. The salvage of hardware and reconstruction of soft tissue defect remain challenging. In this report, we presented our experience on the use of the distally based saphenous neurocutaneous perforator flap combined with vacuum-assisted closure (VAC) therapy for the coverage of the soft tissue defect and the exposed hardware in the lower extremity with fracture. Between January 2008 and July 2010, seven patients underwent the VAC therapy followed by transferring a reversed saphenous neurocutaneous perforator flap for reconstruction of the wound with exposed hardware around the distal tibia. The sizes of the flaps ranged from 6 × 3 cm to 15 × 6 cm. Six flaps survived completely. Partial necrosis occurred in one patient. There were no other complications of repair and donor sites. Bone healing was achieved in all patients. In conclusion, the reversed saphenous neurocutaneous perfortor flaps combined with the VAC therapy might be one of the options to cover the complex wound with exposed hardware in the lower extremities. © 2013 Wiley Periodicals, Inc.

  18. Out-of-Plane Designed Soft Metasurface for Tunable Surface Plasmon Polariton.

    PubMed

    Liu, Xin; Huang, Zhao; Zhu, Chengkai; Wang, Li; Zang, Jianfeng

    2018-02-14

    Reliable and repeatable tunability gives functional diversity for reconfigurable plasmonics devices, while reversible and large mechanical deformation enabled by soft materials provides a new way for the global or partial regulation of metadevices. Here, we demonstrate a soft metasurface with an out-of-plane design for tuning the energy of surface plasmon polaritons (SPPs) bloch wave using theory, simulation, and experiments. Our metasurface is composed of two-layered gold nanoribbon arrays (2GNRs) on a soft substrate. The out-of-plane coupling mechanism is systematically analyzed in terms of separation height effect. Moreover, by harnessing mechanical deformation, continuously tunable plasmonic resonance has been achieved in the visible and near-infrared ranges. We further studied the angle-dependent reflection spectra of our metastructure. Compared with its planar counterpart, our soft and two-layered metastructure exhibits diverse tunability and significant field enhancement by out-of-plane interactions. Our approach in designing soft metasurface with out-of-plane structures can be extended to more-complex photonic devices and finds prominent applications such as biosensing, high-density plasmonic circuits, surface-enhanced luminescence, and surface-enhanced Raman scattering.

  19. Revealing bending and force in a soft body through a plant root inspired approach

    PubMed Central

    Lucarotti, Chiara; Totaro, Massimo; Sadeghi, Ali; Mazzolai, Barbara; Beccai, Lucia

    2015-01-01

    An emerging challenge in soft robotics research is to reveal mechanical solicitations in a soft body. Nature provides amazing clues to develop unconventional components that are capable of compliant interactions with the environment and living beings, avoiding mechanical and algorithmic complexity of robotic design. We inspire from plant-root mechanoperception and develop a strategy able to reveal bending and applied force in a soft body with only two sensing elements of the same kind, and a null computational effort. The stretching processes that lead to opposite tissue deformations on the two sides of the root wall are emulated with two tactile sensing elements, made of soft and stretchable materials, which conform to reversible changes in the shape of the body they are built in and follow its deformations. Comparing the two sensory responses, we can discriminate the concave and the convex side of the bent body. Hence, we propose a new strategy to reveal in a soft body the maximum bending angle (or the maximum deflection) and the externally applied force according to the body's mechanical configuration. PMID:25739743

  20. Mechanochemically Active Soft Robots.

    PubMed

    Gossweiler, Gregory R; Brown, Cameron L; Hewage, Gihan B; Sapiro-Gheiler, Eitan; Trautman, William J; Welshofer, Garrett W; Craig, Stephen L

    2015-10-14

    The functions of soft robotics are intimately tied to their form-channels and voids defined by an elastomeric superstructure that reversibly stores and releases mechanical energy to change shape, grip objects, and achieve complex motions. Here, we demonstrate that covalent polymer mechanochemistry provides a viable mechanism to convert the same mechanical potential energy used for actuation in soft robots into a mechanochromic, covalent chemical response. A bis-alkene functionalized spiropyran (SP) mechanophore is cured into a molded poly(dimethylsiloxane) (PDMS) soft robot walker and gripper. The stresses and strains necessary for SP activation are compatible with soft robot function. The color change associated with actuation suggests opportunities for not only new color changing or camouflaging strategies, but also the possibility for simultaneous activation of latent chemistry (e.g., release of small molecules, change in mechanical properties, activation of catalysts, etc.) in soft robots. In addition, mechanochromic stress mapping in a functional robotic device might provide a useful design and optimization tool, revealing spatial and temporal force evolution within the robot in a way that might be coupled to autonomous feedback loops that allow the robot to regulate its own activity. The demonstration motivates the simultaneous development of new combinations of mechanophores, materials, and soft, active devices for enhanced functionality.

  1. Exchange spring behaviour in SrFe{sub 12}O{sub 19}-CoFe{sub 2}O{sub 4} nanocomposites

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

    Roy, Debangsu, E-mail: debangsu.phy@gmail.com; Anil Kumar, P. S.

    2015-07-15

    Nanocomposites of hard (SrFe{sub 12}O{sub 19}) and soft ferrite (CoFe{sub 2}O{sub 4}) are prepared by mixing individual ferrite components at appropriate weight ratio and subsequent heat treatment. The magnetization of the composites showed hysteresis loop that is characteristic of the exchange spring system. The variation of J{sub r}/J{sub r}(∞) vs. J{sub d}/ J{sub r}(∞) for these nanocomposites are investigated to understand the presence of both the interacting field and the disorder in the system. This is further corroborated with the First Order Reversal Curve analysis (FORC) on the nanocomposites of 1:4 (Cobalt Ferrite: Strontium Ferrite) and 1:16 (Cobalt Ferrite: Strontiummore » Ferrite). The FORC distribution reveals that the pinning mechanism is stronger in the nanocomposite of 1:4 compared to 1:16. However, the nanocomposite of 1:16 exhibit superior exchange coupling strength in contrast to 1:4. The asymmetric nature of the FORC distribution at H{sub c} = 0 Oe for both the nanocomposites validates the intercoupling between the reversible and irreversible magnetization.« less

  2. Covalent-supramolecular hybrid polymers as muscle-inspired anisotropic actuators.

    PubMed

    Chin, Stacey M; Synatschke, Christopher V; Liu, Shuangping; Nap, Rikkert J; Sather, Nicholas A; Wang, Qifeng; Álvarez, Zaida; Edelbrock, Alexandra N; Fyrner, Timmy; Palmer, Liam C; Szleifer, Igal; Olvera de la Cruz, Monica; Stupp, Samuel I

    2018-06-19

    Skeletal muscle provides inspiration on how to achieve reversible, macroscopic, anisotropic motion in soft materials. Here we report on the bottom-up design of macroscopic tubes that exhibit anisotropic actuation driven by a thermal stimulus. The tube is built from a hydrogel in which extremely long supramolecular nanofibers are aligned using weak shear forces, followed by radial growth of thermoresponsive polymers from their surfaces. The hierarchically ordered tube exhibits reversible anisotropic actuation with changes in temperature, with much greater contraction perpendicular to the direction of nanofiber alignment. We identify two critical factors for the anisotropic actuation, macroscopic alignment of the supramolecular scaffold and its covalent bonding to polymer chains. Using finite element analysis and molecular calculations, we conclude polymer chain confinement and mechanical reinforcement by rigid supramolecular nanofibers are responsible for the anisotropic actuation. The work reported suggests strategies to create soft active matter with molecularly encoded capacity to perform complex tasks.

  3. A plant tendril mimic soft actuator with phototunable bending and chiral twisting motion modes

    NASA Astrophysics Data System (ADS)

    Wang, Meng; Lin, Bao-Ping; Yang, Hong

    2016-12-01

    In nature, plant tendrils can produce two fundamental motion modes, bending and chiral twisting (helical curling) distortions, under the stimuli of sunlight, humidity, wetting or other atmospheric conditions. To date, many artificial plant-like mechanical machines have been developed. Although some previously reported materials could realize bending or chiral twisting through tailoring the samples into various ribbons along different orientations, each single ribbon could execute only one deformation mode. The challenging task is how to endow one individual plant tendril mimic material with two different, fully tunable and reversible motion modes (bending and chiral twisting). Here we show a dual-layer, dual-composition polysiloxane-based liquid crystal soft actuator strategy to synthesize a plant tendril mimic material capable of performing two different three-dimensional reversible transformations (bending versus chiral twisting) through modulation of the wavelength band of light stimuli (ultraviolet versus near-infrared). This material has broad application prospects in biomimetic control devices.

  4. A plant tendril mimic soft actuator with phototunable bending and chiral twisting motion modes.

    PubMed

    Wang, Meng; Lin, Bao-Ping; Yang, Hong

    2016-12-22

    In nature, plant tendrils can produce two fundamental motion modes, bending and chiral twisting (helical curling) distortions, under the stimuli of sunlight, humidity, wetting or other atmospheric conditions. To date, many artificial plant-like mechanical machines have been developed. Although some previously reported materials could realize bending or chiral twisting through tailoring the samples into various ribbons along different orientations, each single ribbon could execute only one deformation mode. The challenging task is how to endow one individual plant tendril mimic material with two different, fully tunable and reversible motion modes (bending and chiral twisting). Here we show a dual-layer, dual-composition polysiloxane-based liquid crystal soft actuator strategy to synthesize a plant tendril mimic material capable of performing two different three-dimensional reversible transformations (bending versus chiral twisting) through modulation of the wavelength band of light stimuli (ultraviolet versus near-infrared). This material has broad application prospects in biomimetic control devices.

  5. Photoactivated Composite Biomaterial for Soft Tissue Restoration in Rodents and in Humans

    PubMed Central

    Nahas, Zayna; Reid, Branden; Coburn, Jeannine M.; Axelman, Joyce; Chae, Jemin J.; Guo, Qiongyu; Trow, Robert; Thomas, Andrew; Hou, Zhipeng; Lichtsteiner, Serge; Sutton, Damon; Matheson, Christine; Walker, Patricia; David, Nathaniel; Mori, Susumu; Taube, Janis M.; Elisseeff, Jennifer H.

    2015-01-01

    Soft tissue reconstruction often requires multiple surgical procedures that can result in scars and disfiguration. Facial soft tissue reconstruction represents a clinical challenge because even subtle deformities can severely affect an individual’s social and psychological function. We therefore developed a biosynthetic soft tissue replacement composed of poly(ethylene glycol) (PEG) and hyaluronic acid (HA) that can be injected and photocrosslinked in situ with transdermal light exposure. Modulating the ratio of synthetic to biological polymer allowed us to tune implant elasticity and volume persistence. In a small-animal model, implanted photocrosslinked PEG-HA showed a dose-dependent relationship between increasing PEG concentration and enhanced implant volume persistence. In direct comparison with commercial HA injections, the PEG-HA implants maintained significantly greater average volumes and heights. Reversibility of the implant volume was achieved with hyaluronidase injection. Pilot clinical testing in human patients confirmed the feasibility of the transdermal photocrosslinking approach for implantation in abdomen soft tissue, although an inflammatory response was observed surrounding some of the materials. PMID:21795587

  6. Cyclic stretching of soft substrates induces spreading and growth

    PubMed Central

    Cui, Yidan; Hameed, Feroz M.; Yang, Bo; Lee, Kyunghee; Pan, Catherine Qiurong; Park, Sungsu; Sheetz, Michael

    2015-01-01

    In the body, soft tissues often undergo cycles of stretching and relaxation that may affect cell behaviour without changing matrix rigidity. To determine whether transient forces can substitute for a rigid matrix, we stretched soft pillar arrays. Surprisingly, 1–5% cyclic stretching over a frequency range of 0.01–10 Hz caused spreading and stress fibre formation (optimum 0.1 Hz) that persisted after 4 h of stretching. Similarly, stretching increased cell growth rates on soft pillars comparative to rigid substrates. Of possible factors linked to fibroblast growth, MRTF-A (myocardin-related transcription factor-A) moved to the nucleus in 2 h of cyclic stretching and reversed on cessation; but YAP (Yes-associated protein) moved much later. Knockdown of either MRTF-A or YAP blocked stretch-dependent growth. Thus, we suggest that the repeated pulling from a soft matrix can substitute for a stiff matrix in stimulating spreading, stress fibre formation and growth. PMID:25704457

  7. Exchange coupling interaction in L10-FePd/α-Fe nanocomposite magnets with large maximum energy products.

    PubMed

    Sakuma, Noritsugu; Ohshima, Tsubasa; Shoji, Tetsuya; Suzuki, Yoshihito; Sato, Ryota; Wachi, Ayako; Kato, Akira; Kawai, Yoichiro; Manabe, Akira; Teranishi, Toshiharu

    2011-04-26

    Nanocomposite magnets (NCMs) consisting of hard and soft magnetic phases are expected to be instrumental in overcoming the current theoretical limit of magnet performance. In this study, structural analyses were performed on L1(0)-FePd/α-Fe NCMs with various hard/soft volume fractions, which were formed by annealing Pd/γ-Fe(2)O(3) heterostructured nanoparticles and pure Pd nanoparticles. The sample with a hard/soft volume ratio of 82/18 formed by annealing at 773 K had the largest maximum energy product (BH(max) = 10.3 MGOe). In such a sample, the interface between the hard and soft phases was coherent and the phase sizes were optimized, both of which effectively induced exchange coupling. This exchange coupling was directly observed by visualizing the magnetic interaction between the hard and soft phases using a first-order reversal curve diagram, which is a valuable tool to improve the magnetic properties of NCMs.

  8. Spheromak Merging Experiments on SSX

    NASA Astrophysics Data System (ADS)

    Brown, M. R.; Kornack, T. W.; Sollins, P. K.; Luh, W. J.

    1997-11-01

    Spheromak merging experiments are underway at the Swarthmore Spheromak Experiment (SSX) at Swarthmore College. The spheromaks are formed by identical magnetized plasma guns and equilibrium is established in close fitting 0.5 m diameter copper flux conservers. Partial merging is achieved through openings in the back wall. We observe the formation of a reconnection boundary layer at the interface of the two spheromaks using a linear probe array. The characteristic scale of the flux reversal is about 1 cm (consistent with the diffusion scale δ_diff, the ion Larmor radius ρi and the ion inertial length c/ω_pi). Movies of the formation and evolution of the layer will be presented. Correlations between reconnection events and pulses of soft x-rays and energetic particles will be presented if available. Plans for 2D and 3D imaging of the layer will also be discussed.

  9. Stimuli-responsive Materials and Structures with Electrically Tunable Mechanical Properties

    NASA Astrophysics Data System (ADS)

    Auletta, Jeffrey Thomas

    Electricity, a convenient stimulus, was used to manipulate the mechanical properties of two classes of materials, each with a different mechanism. In the first system, macroscale electroplastic elastomer hydrogels (EPEs) were reversibly cycled through soft and hard states by sequential application of oxidative and reductive potentials. Electrochemically reversible crosslinks were switched between strongly binding Fe3+ and weak to non-binding Fe2+, as determined by potentiometric titration.With the incorporation of graphene oxide (GO) into the EPE, a significant enhancement in modulus and toughness was observed, allowing for the preparation of thinner EPE samples, which could be reversibly cycled between soft and hard states over 30 minutes. Further characterization of this EPE by magnetic susceptibility measurements suggested the formation of multinuclear iron clusters within the gel. Copper-derived EPEs which exploited the same redox-controlled mechanism for switching between hard and soft states were also prepared. Here, the density of temporary crosslinks and the mechanical properties were controlled by reversibly switching between the +1 and +2 oxidation states, using a combination of electrochemical/air oxidation and chemical reduction. In addition to undergoing redox-controlled changes in modulus, these EPEs exhibited shape memory. In the second system, electroadhesion between ionomer layers was exploited to create laminate structures whose rigidity depended on the reversible polarization of the dielectric polymers. The role of the counter-ion in determining the intrinsic and electroadhesive properties of poly(ethylene-co-acrylic acid) ionomers in bi- and tri-layered laminate structures was examined. PEAA ionomers were prepared with three tetraalkylammonium cations (NR4 +, R = methyl, TMA+; ethyl, TEA+; and propyl, TPA+). Reflecting the increasing hydrophobicity of the longer alkyl chains, water uptake changed as a function of counterion with TMA+ > TEA+ > TPA+. The glass transition temperatures, electrical resistivities, elastic moduli, and coefficients of friction were measured and found to depend on the cation identity. Overall, the cation-influenced mechanical properties of the ionomer determined the flexural rigidity range, but not the magnitude of the rigidity change, between the on and off states.

  10. Soft cooperation systems and games

    NASA Astrophysics Data System (ADS)

    Fernández, J. R.; Gallego, I.; Jiménez-Losada, A.; Ordóñez, M.

    2018-04-01

    A cooperative game for a set of agents establishes a fair allocation of the profit obtained for their cooperation. In order to obtain this allocation, a characteristic function is known. It establishes the profit of each coalition of agents if this coalition decides to act alone. Originally players are considered symmetric and then the allocation only depends on the characteristic function; this paper is about cooperative games with an asymmetric set of agents. We introduced cooperative games with a soft set of agents which explains those parameters determining the asymmetry among them in the cooperation. Now the characteristic function is defined not over the coalitions but over the soft coalitions, namely the profit depends not only on the formed coalition but also on the attributes considered for the players in the coalition. The best known of the allocation rules for cooperative games is the Shapley value. We propose a Shapley kind solution for soft games.

  11. Mutual influence between macrospin reversal order and spin-wave dynamics in isolated artificial spin-ice vertices

    DOE PAGES

    Montoncello, F.; Giovannini, L.; Bang, Wonbae; ...

    2018-01-18

    In this paper, we theoretically and experimentally investigate magnetization reversal and associated spin-wave dynamics of isolated threefold vertices that constitute a Kagome lattice. The three permalloy macrospins making up the vertex have an elliptical cross section and a uniform thickness. We study the dc magnetization curve and the frequency versus field curves (dispersions) of those spin-wave modes that produce the largest response. We also investigate each macrospin reversal from a dynamic perspective, by performing micromagnetic simulations of the reversal processes, and revealing their relationships to the soft-mode profile calculated at the equilibrium state immediately before reversal. The theoretical results aremore » compared with the measured magnetization curves and ferromagnetic resonance spectra. Finally, the agreement achieved suggests that a much deeper understanding of magnetization reversal and accompanying hysteresis can be achieved by combining theoretical calculations with static and dynamic magnetization experiments.« less

  12. Mutual influence between macrospin reversal order and spin-wave dynamics in isolated artificial spin-ice vertices

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

    Montoncello, F.; Giovannini, L.; Bang, Wonbae

    In this paper, we theoretically and experimentally investigate magnetization reversal and associated spin-wave dynamics of isolated threefold vertices that constitute a Kagome lattice. The three permalloy macrospins making up the vertex have an elliptical cross section and a uniform thickness. We study the dc magnetization curve and the frequency versus field curves (dispersions) of those spin-wave modes that produce the largest response. We also investigate each macrospin reversal from a dynamic perspective, by performing micromagnetic simulations of the reversal processes, and revealing their relationships to the soft-mode profile calculated at the equilibrium state immediately before reversal. The theoretical results aremore » compared with the measured magnetization curves and ferromagnetic resonance spectra. Finally, the agreement achieved suggests that a much deeper understanding of magnetization reversal and accompanying hysteresis can be achieved by combining theoretical calculations with static and dynamic magnetization experiments.« less

  13. Emergent electromechanical coupling of electrets and some exact relations — The effective properties of soft materials with embedded external charges and dipoles

    NASA Astrophysics Data System (ADS)

    Liu, Liping; Sharma, Pradeep

    2018-03-01

    Soft robotics, energy harvesting, large-deformation sensing and actuation, are just some of the applications that can be enabled by soft dielectrics that demonstrate substantive electromechanical coupling. Most soft dielectrics including elastomers, however, are not piezoelectric and rely on the universally present electrostriction and the Maxwell stress effect to enable the aforementioned applications. Electrostriction is a one-way electromechanical coupling and the induced elastic strain scales as (∝E2) upon the application of an electric field, E. The quadratic dependence of electrostriction on the electric field and the one-way coupling imply that, (i) A rather high voltage is required to induce appreciable strain, (ii) reversal of an applied bias will not reverse the sign of the deformation, and (iii) since it is a one-way coupling i.e. electrical stimuli may cause mechanical deformation but electricity cannot be generated by mechanical deformation, prospects for energy harvesting are rather difficult. An interesting approach for realizing an apparent piezoelectric-like behavior is to dope soft dielectrics with immobile charges and dipoles. Such materials, called electrets, are rather unique composites where a secondary material (in principle) is not necessary. Both experiments and supporting theoretical work have shown that soft electrets can exhibit a very large electromechanical coupling including a piezoelectric-like response. In this work, we present a homogenization theory for electret materials and provide, in addition to several general results, variational bounds and closed-form expressions for specific microstructures such as laminates and ellipsoidal inclusions. While we consider the nonlinear coupled problem, to make analytical progress, we work within the small-deformation setting. The specific conditions necessary to obtain a piezoelectric-like response and enhanced electrostriction are highlighted. There are very few universal, microstructure-independent exact results in the theory of composites. We succeed in establishing several such relations in the context of electrets.

  14. Soft-tissue facial characteristics of attractive Chinese men compared to normal men

    PubMed Central

    Wu, Feng; Li, Junfang; He, Hong; Huang, Na; Tang, Youchao; Wang, Yuanqing

    2015-01-01

    Objective: To compare the facial characteristics of attractive Chinese men with those of reference men. Materials and Methods: The three-dimensional coordinates of 50 facial landmarks were collected in 40 healthy reference men and in 40 “attractive” men, soft tissue facial angles, distances, areas, and volumes were computed and compared using analysis of variance. Results: When compared with reference men, attractive men shared several similar facial characteristics: relatively large forehead, reduced mandible, and rounded face. They had a more acute soft tissue profile, an increased upper facial width and middle facial depth, larger mouth, and more voluminous lips than reference men. Conclusions: Attractive men had several facial characteristics suggesting babyness. Nonetheless, each group of men was characterized by a different development of these features. Esthetic reference values can be a useful tool for clinicians, but should always consider the characteristics of individual faces. PMID:26221357

  15. Analysis of Ten Reverse Engineering Tools

    NASA Astrophysics Data System (ADS)

    Koskinen, Jussi; Lehmonen, Tero

    Reverse engineering tools can be used in satisfying the information needs of software maintainers. Especially in case of maintaining large-scale legacy systems tool support is essential. Reverse engineering tools provide various kinds of capabilities to provide the needed information to the tool user. In this paper we analyze the provided capabilities in terms of four aspects: provided data structures, visualization mechanisms, information request specification mechanisms, and navigation features. We provide a compact analysis of ten representative reverse engineering tools for supporting C, C++ or Java: Eclipse Java Development Tools, Wind River Workbench (for C and C++), Understand (for C++), Imagix 4D, Creole, Javadoc, Javasrc, Source Navigator, Doxygen, and HyperSoft. The results of the study supplement the earlier findings in this important area.

  16. Magnetostatic effects on switching in small magnetic tunnel junctions

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

    Bapna, Mukund; Piotrowski, Stephan K.; Oberdick, Samuel D.

    Perpendicular CoFeB/MgO/CoFeB magnetic tunnel junctions with diameters under 100 nm are investigated by conductive atomic force microscopy. Minor loops of the tunnel magnetoresistance as a function of applied magnetic field reveal the hysteresis of the soft layer and an offset due to the magnetostatic field of the hard layer. Within the hysteretic region, telegraph noise is observed in the tunnel current. Simulations show that in this range, the net magnetic field in the soft layer is spatially inhomogeneous, and that antiparallel to parallel switching tends to start near the edge, while parallel to antiparallel reversal favors nucleation in the interior ofmore » the soft layer. As the diameter of the tunnel junction is decreased, the average magnitude of the magnetostatic field increases, but the spatial inhomogeneity across the soft layer is reduced.« less

  17. Optimizing Double-Network Hydrogel for Biomedical Soft Robots.

    PubMed

    Banerjee, Hritwick; Ren, Hongliang

    2017-09-01

    Double-network hydrogel with standardized chemical parameters demonstrates a reasonable and viable alternative to silicone in soft robotic fabrication due to its biocompatibility, comparable mechanical properties, and customizability through the alterations of key variables. The most viable hydrogel sample in our article shows tensile strain of 851% and maximum tensile strength of 0.273 MPa. The elasticity and strength range of this hydrogel can be customized according to application requirements by simple alterations in the recipe. Furthermore, we incorporated Agar/PAM hydrogel into our highly constrained soft pneumatic actuator (SPA) design and eventually produced SPAs with escalated capabilities, such as larger range of motion, higher force output, and power efficiency. Incorporating SPAs made of Agar/PAM hydrogel resulted in low viscosity, thermos-reversibility, and ultralow elasticity, which we believe can help to combine with the other functions of hydrogel, tailoring a better solution for fabricating biocompatible soft robots.

  18. Modular microfluidic systems using reversibly attached PDMS fluid control modules

    NASA Astrophysics Data System (ADS)

    Skafte-Pedersen, Peder; Sip, Christopher G.; Folch, Albert; Dufva, Martin

    2013-05-01

    The use of soft lithography-based poly(dimethylsiloxane) (PDMS) valve systems is the dominating approach for high-density microscale fluidic control. Integrated systems enable complex flow control and large-scale integration, but lack modularity. In contrast, modular systems are attractive alternatives to integration because they can be tailored for different applications piecewise and without redesigning every element of the system. We present a method for reversibly coupling hard materials to soft lithography defined systems through self-aligning O-ring features thereby enabling easy interfacing of complex-valve-based systems with simpler detachable units. Using this scheme, we demonstrate the seamless interfacing of a PDMS-based fluid control module with hard polymer chips. In our system, 32 self-aligning O-ring features protruding from the PDMS fluid control module form chip-to-control module interconnections which are sealed by tightening four screws. The interconnection method is robust and supports complex fluidic operations in the reversibly attached passive chip. In addition, we developed a double-sided molding method for fabricating PDMS devices with integrated through-holes. The versatile system facilitates a wide range of applications due to the modular approach, where application specific passive chips can be readily attached to the flow control module.

  19. Super strong dopamine hydrogels with shape memory and bioinspired actuating behaviours modulated by solvent exchange.

    PubMed

    Huang, Jiahe; Liao, Jiexin; Wang, Tao; Sun, Weixiang; Tong, Zhen

    2018-03-28

    Dopamine-containing hydrogels were synthesized by copolymerization of dopamine methacrylamide (DMA), N,N-dimethylacrylamide (DMAA), and an N,N'-methylenebisacrylamide (BIS) crosslinker in a mixed solvent of water and DMSO. The association of DMA was formed by simply immersing in water to facilely reinforce the hydrogel due to the introduction of the second physical crosslinking. The tensile strength of the hydrogels was increased greatly and regulated in a wide range from 200 kPa to over 2 MPa. The association of DMA was destroyed upon immersing in DMSO. This reversible formation and dissociation of the association structure endowed the hydrogel with shape memory and actuating capabilities. Rapid shape fixing in water and complete shape recovery in DMSO was realized within several minutes. Bioinspired functional soft actuators were designed based on the reversible association and metal ion coordination of DMA, including fast responsive hydrogel tentacles, programable multiple shape change, reversible and versatile painting and writing "hydrogel paper". The facile preparation and strength regulation provide a new way to design novel soft actuators through solvent exchange, and will inspire more complex applications upon combining the association with other properties of mussel inspired dopamine derivatives.

  20. Relationships of Quality Characteristics with Size Exclusion HPLC Chromatogram of Protein Extract in Soft-White Winter Wheats.

    USDA-ARS?s Scientific Manuscript database

    This study investigated relationships between molecular weight distributions of unreduced grain proteins and grain, flour, and end-use quality characteristics of soft white winter wheats grown in Oregon. Absorbance area and area % values of protein fractions separated by size exclusion HPLC (SE-HPL...

  1. Reliability and validity of soft copy images based on flat-panel detector in pneumoconiosis classification: comparison with the analog radiographs.

    PubMed

    Lee, Won-Jeong; Choi, Byung-Soon

    2013-06-01

    The aim of this study was to evaluate the reliability and validity of soft copy images based on flat-panel detector of digital radiography (DR-FPD soft copy images) compared to analog radiographs (ARs) in pneumoconiosis classification and diagnosis. DR-FPD soft copy images and ARs from 349 subjects were independently read by four-experienced readers according to the International Labor Organization 2000 guidelines. DR-FPD soft copy images were used to obtain consensus reading (CR) by all readers as the gold standard. Reliability and validity were evaluated by a κ and receiver operating characteristic analysis, respectively. In small opacity, overall interreader agreement of DR-FPD soft copy images was significantly higher than that of ARs, but it was not significantly different in large opacity and costophrenic angle obliteration. In small opacity, agreement of DR-FPD soft copy images with CR was significantly higher than that of ARs with CR. It was also higher than that of ARs with CR in pleural plaque and thickening. Receiver operating characteristic areas were not different significantly between DR-FPD soft copy images and ARs. DR-FPD soft copy images showed accurate and reliable results in pneumoconiosis classification and diagnosis compared to ARs. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.

  2. Bamboo leaf ash as the stabilizer for soft soil treatment

    NASA Astrophysics Data System (ADS)

    Rahman, A. S. A.; Jais, I. B. M.; Sidek, N.; Ahmad, J.; Rosli, M. I. F.

    2018-04-01

    Soft soil is a type of soil that have the size of particle less than 0.063mm. The strength of the soft soil does not fulfil the requirement for construction. The present of soft soil at the construction site always give a lot of problems and issues to geotechnical sector. Soil settlement is one of the problems that related to soft soil. The determination of the soft soil physical characteristics will provide a detail description on its characteristic. Soft soil need to be treated in order to gain the standard strength for construction. One of the method to strengthen the soft soil is by using pozzolanic material as a treatment method for soft soil. Furthermore bamboo leaf ash is one of the newly founded materials that contain pozzolanic material. Any material that consist of Silicon Dioxide (SiO2) as the main component and followed by Aluminium Oxide (Al2O3) and Iron Oxide (Fe2O3) are consider as pozzolanic material. Bamboo leaf ash is mix with the cement as the treatment material. Bamboo leaf ash will react with the cement to produce additional cement binder. Thus, it will increase the soil strength and will ease the geotechnical sector to achieve high quality of construction product.

  3. Cellular Dichotomy Between Anchorage-Independent Growth Responses to bFGF and TA Reflects Molecular Switch in Commitment to Carcinogenesis

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

    Waters, Katrina M.; Tan, Ruimin; Opresko, Lee K.

    2009-11-01

    We have investigated gene expression patterns underlying reversible and irreversible anchorage-independent growth (AIG) phenotypes to identify more sensitive markers of cell transformation for studies directed at interrogating carcinogenesis responses. In JB6 mouse epidermal cells, basic fibroblast growth factor (bFGF) induces an unusually efficient and reversible AIG response, relative to 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced AIG which is irreversible. The reversible and irreversible AIG phenotypes are characterized by largely non-overlapping global gene expression profiles. However, a subset of differentially expressed genes were identified as common to reversible and irreversible AIG phenotypes, including genes regulated in a reciprocal fashion. Hepatic leukemia factor (HLF) andmore » D-site albumin promoter-binding protein (DBP) were increased in both bFGF and TPA soft agar colonies and selected for functional validation. Ectopic expression of human HLF and DBP in JB6 cells resulted in a marked increase in TPA- and bFGF-regulated AIG responses. HLF and DBP expression were increased in soft agar colonies arising from JB6 cells exposed to gamma radiation and in a human basal cell carcinoma tumor tissue, relative to paired non-tumor tissue. Subsequent biological network analysis suggests that many of the differentially expressed genes that are common to bFGF- and TPA-dependent AIG are regulated by c-Myc, SP-1 and HNF-4 transcription factors. Collectively, we have identified a potential molecular switch that mediates the transition from reversible to irreversible AIG.« less

  4. Characteristics of an actuator-driven pulsed water jet generator to dissecting soft tissue.

    PubMed

    Seto, Takeshi; Yamamoto, Hiroaki; Takayama, Kazuyoshi; Nakagawa, Atsuhiro; Tominaga, Teiji

    2011-05-01

    This paper reports characteristics of an actuator-driven pulsed water jet generator applied, in particular, to dissect soft tissues. Results of experiments, by making use of high speed recording of optical visualization and varying nozzle diameter, actuator time interval, and their effects on dissection performance are presented. Jet penetration characteristics are compared with continuous water jet and hence potential assessment of pulsed water jets to clinical applications is performed.

  5. Incorporation and Effects of Nanoparticles in a Supramolecular Polymer

    DTIC Science & Technology

    2016-05-01

    Oak Ridge, TN Robert H Lambeth and Frederick L Beyer Weapons and Materials Research Directorate, ARL Approved for...nanocomposites: phase diagram, rheology and structure using a combined small angle neutron scattering and reverse Monte Carlo approach. Soft Matter. 2010;6

  6. Advanced nano lithography via soft materials-derived and reversible nano-patterning methodology for molding of infrared nano lenses

    NASA Astrophysics Data System (ADS)

    Park, Jae Hong; Jang, Hyun Ik; Park, Jun Yong; Jeon, Seok Woo; Kim, Woo Choong; Kim, Hee Yeoun; Ahn, Chi Won

    2015-03-01

    The methodology suggested in this research provides the great possibility of creating nanostructures composed of various materials, such as soft polymer, hard polymer, and metal, as well as Si. Such nanostructures are required for a vast range of optical and display devices, photonic components, physical devices, energy devices including electrodes of secondary batteries, fuel cells, solar cells, and energy harvesters, biological devices including biochips, biomimetic or biosimilar structured devices, and mechanical devices including micro- or nano-scale sensors and actuators.

  7. Multidisciplinary Analysis of Cyclophilin a Function in Human Breast Cancer

    DTIC Science & Technology

    2009-03-01

    reversible following washing and medium change; at concen- trations of z30 Ag/mL, these effects were not reversible and cell death ensued (data not...proliferation, but did not induce the 278 death of breast cancer cells. Treatment at higher doses (30 μg CsA/ml and above) 279 resulted in the...induction of cell death . These studies were extended to examine the 280 effects of CsA treatment on anchorage-independent growth, as measured by soft agar

  8. Quality characteristics of northern-style Chinese steamed bread prepared from soft red winter wheat flours with waxy wheat flour substitution

    USDA-ARS?s Scientific Manuscript database

    Quality characteristics of Chinese steamed bread (CSB) prepared from two soft red winter (SRW) wheat flours blended with 0-30% waxy wheat flour (WWF) were determined to estimate the influence of starch amylose content. The increased proportion of WWF in blends raised mixograph absorption with insign...

  9. Non-linear Mechanics of Three-dimensional Architected Materials; Design of Soft and Functional Systems and Structures

    NASA Astrophysics Data System (ADS)

    Babaee, Sahab

    In the search for materials with new properties, there have been significant advances in recent years aimed at the construction of architected materials whose behavior is governed by structure, rather than composition. Through careful design of the material's architecture, new mechanical properties have been demonstrated, including negative Poisson's ratio, high stiffness to weight ratio and mechanical cloaking. However, most of the proposed architected materials (also known as mechanical metamaterials) have a unique structure that cannot be recon figured after fabrication, making them suitable only for a specific task. This thesis focuses on the design of architected materials that take advantage of the applied large deformation to enhance their functionality. Mechanical instabilities, which have been traditionally viewed as a failure mode with research focusing on how to avoid them, are exploited to achieve novel and tunable functionalities. In particular I demonstrate the design of mechanical metamaterials with tunable negative Poisson ratio, adaptive phononic band gaps, acoustic switches, and reconfigurable origami-inspired waveguides. Remarkably, due to large deformation capability and full reversibility of soft materials, the responses of the proposed designs are reversible, repeatable, and scale independent. The results presented here pave the way for the design of a new class of soft, active, adaptive, programmable and tunable structures and systems with unprecedented performance and improved functionalities.

  10. Point-of-Purchase Price and Education Intervention to Reduce Consumption of Sugary Soft Drinks

    PubMed Central

    Chandra, Amitabh; McManus, Katherine D.; Willett, Walter C.

    2010-01-01

    Objectives. We investigated whether a price increase on regular (sugary) soft drinks and an educational intervention would reduce their sales. Methods. We implemented a 5-phase intervention at the Brigham and Women's Hospital cafeteria in Boston, Massachusetts. After posting existing prices of regular and diet soft drinks and water during baseline, we imposed several interventions in series: a price increase of 35% on regular soft drinks, a reversion to baseline prices (washout), an educational campaign, and a combination price and educational period. We collected data from a comparison site, Beth Israel Deaconess Hospital, also in Boston, for the final 3 phases. Results. Sales of regular soft drinks declined by 26% during the price increase phase. This reduction in sales persisted throughout the study period, with an additional decline of 18% during the combination phase compared with the washout period. Education had no independent effect on sales. Analysis of the comparison site showed no change in regular soft drink sales during the study period. Conclusions. A price increase may be an effective policy mechanism to decrease sales of regular soda. Further multisite studies in varied populations are warranted to confirm these results. PMID:20558801

  11. Point-of-purchase price and education intervention to reduce consumption of sugary soft drinks.

    PubMed

    Block, Jason P; Chandra, Amitabh; McManus, Katherine D; Willett, Walter C

    2010-08-01

    We investigated whether a price increase on regular (sugary) soft drinks and an educational intervention would reduce their sales. We implemented a 5-phase intervention at the Brigham and Women's Hospital cafeteria in Boston, Massachusetts. After posting existing prices of regular and diet soft drinks and water during baseline, we imposed several interventions in series: a price increase of 35% on regular soft drinks, a reversion to baseline prices (washout), an educational campaign, and a combination price and educational period. We collected data from a comparison site, Beth Israel Deaconess Hospital, also in Boston, for the final 3 phases. Sales of regular soft drinks declined by 26% during the price increase phase. This reduction in sales persisted throughout the study period, with an additional decline of 18% during the combination phase compared with the washout period. Education had no independent effect on sales. Analysis of the comparison site showed no change in regular soft drink sales during the study period. A price increase may be an effective policy mechanism to decrease sales of regular soda. Further multisite studies in varied populations are warranted to confirm these results.

  12. Exploratory Practice and Soft Systems Methodology

    ERIC Educational Resources Information Center

    Tajino, Akira; Smith, Craig

    2005-01-01

    This paper aims to demonstrate that Soft Systems Methodology (SSM), a soft systems approach developed in management studies (see Checkland, 1981), can be usefully linked with Exploratory Practice (EP), a form of practitioner research for language classrooms. Some compatible SSM and EP characteristics, in tandem, could enhance continual efforts to…

  13. Magnetic drops in a soft-magnetic cylinder

    NASA Astrophysics Data System (ADS)

    Hertel, Riccardo; Kirschner, Jürgen

    2004-07-01

    Magnetization reversal in a cylindrical ferromagnetic particle seems to be a simple textbook problem in magnetism. But at a closer look, the magnetization reversal dynamics in a cylinder is far from being trivial. The difficulty arises from the central axis, where the magnetization switches in a discontinuous fashion. Micromagnetic computer simulations allow for a detailed description of the evolution of the magnetic structure on the sub-nanosecond time scale. The switching process involves the injection of a magnetic point singularity (Bloch point) into the cylinder. Further point singularities may be generated and annihilated periodically during the reversal process. This results in the temporary formation of micromagnetic drops, i.e., isolated, non-reversed regions. This surprising feature in dynamic micromagnetism is due to different mobilities of domain wall and Bloch point.

  14. Nanostructure-directed physisorption vs chemisorption at semiconductor interfaces: the inverse of the HSAB concept.

    PubMed

    Gole, James L; Ozdemir, Serdar

    2010-08-23

    A concept, complementary to that of hard and soft acid-base interactions (HSAB-dominant chemisorption) and consistent with dominant physisorption to a semiconductor interface, is presented. We create a matrix of sensitivities and interactions with several basic gases. The concept, based on the reversible interaction of hard-acid surfaces with soft bases, hard-base surfaces with soft acids, or vice versa, corresponds 1) to the inverse of the HSAB concept and 2) to the selection of a combination of semiconductor interface and analyte materials, which can be used to direct a physisorbed vs chemisorbed interaction. The technology, implemented on nanopore coated porous silicon micropores, results in the coupling of acid-base chemistry with the depletion or enhancement of majority carriers in an extrinsic semiconductor. Using the inverse-HSAB (IHSAB) concept, significant and predictable changes in interface sensitivity for a variety of gases can be implemented. Nanostructured metal oxide particle depositions provide selectivity and complement a highly efficient electrical contact to a porous silicon nanopore covered microporous interface. The application of small quantities (much less than a monolayer) of nanostructured metals, metal oxides, and catalysts which focus the physisorbtive and chemisorbtive interactions of the interface, can be made to create a range of notably higher sensitivities for reversible physisorption. This is exemplified by an approach to reversible, sensitive, and selective interface responses. Nanostructured metal oxides developed from electroless gold (Au(x)O), tin (SnO(2)), copper (Cu(x)O), and nickel (NiO) depositions, nanoalumina, and nanotitania are used to demonstrate the IHSAB concept and provide for the detection of gases, including NH(3), PH(3), CO, NO, and H(2)S, in an array-based format to the sub-ppm level.

  15. Development of hand exoskeleton for rehabilitation of post-stroke patient

    NASA Astrophysics Data System (ADS)

    Zaid, Amran Mohd; Chean, Tee Chu; Sukor, Jumadi Abdul; Hanafi, Dirman

    2017-10-01

    Degenerative muscle diseases characterized by loss of strength in human hand significantly affect the physical of affected individuals. A soft assistive exoskeleton glove is designed to help post-stroke patient with their rehabilitation process. The glove uses soft bending actuator which has a rubber like tender characteristic. Due to its rubber like characteristic, flexion of finger can be achieved easily through pneumatic air without considering other hand motions. The application involves a post-stroke patient to wear the soft exoskeleton glove on his paralyzed hand and control the actuation of the glove by using pneumatic air source. The fabrication of the soft bending actuator involves silicone rubber Mold Star® 15 SLOW which falls within the soft category of shore A hardness scale. The soft bending actuator is controlled by Arduino Mega 2560 as main controller board and relay module is used to trigger the 3/2-way single solenoid valve by switching on the 24VDC power supply. The actuation of the soft bending actuator can be manipulated by setting delay ON and OFF for the relay switching. Thus, the repetition of the bending motion can be customized to fulfil the rehabilitation needs of the patient.

  16. A multi-frame soft x-ray pinhole imaging diagnostic for single-shot applicationsa)

    NASA Astrophysics Data System (ADS)

    Wurden, G. A.; Coffey, S. K.

    2012-10-01

    For high energy density magnetized target fusion experiments at the Air Force Research Laboratory FRCHX machine, obtaining multi-frame soft x-ray images of the field reversed configuration (FRC) plasma as it is being compressed will provide useful dynamics and symmetry information. However, vacuum hardware will be destroyed during the implosion. We have designed a simple in-vacuum pinhole nosecone attachment, fitting onto a Conflat window, coated with 3.2 mg/cm2 of P-47 phosphor, and covered with a thin 50-nm aluminum reflective overcoat, lens-coupled to a multi-frame Hadland Ultra intensified digital camera. We compare visible and soft x-ray axial images of translating (˜200 eV) plasmas in the FRX-L and FRCHX machines in Los Alamos and Albuquerque.

  17. The contribution of 180° domain wall motion to dielectric properties quantified from in situ X-ray diffraction

    DOE PAGES

    Fancher, C. M.; Brewer, S.; Chung, C. C.; ...

    2016-12-27

    Here, the contribution of 180° domain wall motion to polarization and dielectric properties of ferroelectric materials has yet to be determined experimentally. In this paper, an approach for estimating the extent of (180°) domain reversal during application of electric fields is presented. We demonstrate this method by determining the contribution of domain reversal to polarization in soft lead zirconate titanate during application of strong electric fields. At the maximum applied field, domain reversal was determined to account for >80% of the measured macroscopic polarization. We also apply the method to quantify the contribution of domain reversal to the weak-field dielectricmore » permittivity of BaTiO 3. The results of this analysis determined that domain reversal accounts for up to ~70% of the macroscopic dielectric permittivity in BaTiO 3. These results demonstrate the predominance of domain reversal to high and low-field dielectric response in ferroelectric polycrystalline materials.« less

  18. The contribution of 180° domain wall motion to dielectric properties quantified from in situ X-ray diffraction

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

    Fancher, C. M.; Brewer, S.; Chung, C. C.

    2017-03-01

    The contribution of 180° domain wall motion to polarization and dielectric properties of ferroelectric materials has yet to be determined experimentally. In this paper, an approach for estimating the extent of (180°) domain reversal during application of electric fields is presented. We demonstrate this method by determining the contribution of domain reversal to polarization in soft lead zirconate titanate during application of strong electric fields. At the maximum applied field, domain reversal was determined to account for >80% of the measured macroscopic polarization. We also apply the method to quantify the contribution of domain reversal to the weak-field dielectric permittivitymore » of BaTiO 3. The results of this analysis determined that domain reversal accounts for up to ~70% of the macroscopic dielectric permittivity in BaTiO 3. These results demonstrate the predominance of domain reversal to high and low-field dielectric response in ferroelectric polycrystalline materials.« less

  19. A Conceptual Framework for Predicting the Toxicity of Reactive Chemicals: Modeling Soft Electrophilicity

    EPA Science Inventory

    Although the literature is replete with QSAR models developed for many toxic effects caused by reversible chemical interactions, the development of QSARs for the toxic effects of reactive chemicals lacks a consistent approach. While limitations exit, an appropriate starting-point...

  20. Characteristics and Significance of Magma Emplacement Horizons, Black Sturgeon Sill, Nipigon, Ontario

    NASA Astrophysics Data System (ADS)

    Zieg, M. J.; Hone, S. V.

    2017-12-01

    Spatial scales strongly control the timescales of processes in igneous intrusions, particularly through the thermal evolution of the magma, which in turn governs the evolution of crystallinity, viscosity, and other important physical and chemical properties of the system. In this study, we have collected a highly detailed data set comprising geochemical (bulk rock composition), textural (size and alignment of plagioclase crystals), and mineralogical (modal abundance) profiles through the central portion of the 250 m thick Black Sturgeon diabase sill. In this data, we have identified characteristic signals in texture (soft and somewhat diffuse chills), composition (reversals in differentiation trends), and mineralogy (olivine accumulations), all coinciding and recurring at roughly 10 meter intervals. Based on these signatures, we are able to map out multiple zones representing discrete pulses of magma that were emplaced sequentially as the intrusion was inflated. Simple thermal calculations suggest that each 10 meters of new crystallization would require repose times on the order of 10-100 years. To build up 250 meters of magma at this rate would only require approximately 250-2500 years, significantly less than the thermal lifetime of the entire sill. The soft chills we observe in the Black Sturgeon sill are therefore consistent with a system that remained warm throughout the emplacement process. Successive pulses were injected into partially crystalline mush, rather than pure liquid (which would result in hybridization) or solid (which would produce sharp hard chills). Episodic emplacement is by now widely recognized as a fundamental process in the formation of large felsic magma chambers; our results suggest that this also may be an important consideration in understanding the evolution of smaller mafic intrusions.

  1. Tracking gas-liquid coexistence in fluids of charged soft dumbbells.

    PubMed

    Braun, Heiko; Hentschke, Reinhard

    2009-10-01

    The existence of gas-liquid coexistence in dipolar fluids with no other contribution to attractive interaction than dipole-dipole interaction is a basic and open question in the theory of fluids. Recent Monte Carlo work by Camp and co-workers indicates that a fluid of charged hard dumbbells does exhibit gas-liquid (g-l) coexistence. This system has the potential to answer the above fundamental question because the charge-to-charge separation, d , on the dumbbells may be reduced to, at least in principle, yield the dipolar fluid limit. Using the molecular-dynamics technique we present simulation results for the g-l critical point of charged soft dumbbells at fixed dipole moment as function of d . We do find a g-l critical point at finite temperature even at the smallest d value (10;{-4}) . Reversible aggregation appears to play less a role than in related model systems as d becomes small. Consequently attempts to interpret the simulation results using either an extension of Flory's lattice theory for polymer systems, which includes reversible assembly of monomers into chains, or the defect model for reversible networks proposed by Tlusty and Safran are not successful. The overall best qualitative interpretation of the critical parameters is obtained by considering the dumbbells as dipoles immersed in a continuum dielectric.

  2. Effects of protein-coated nanofibers on conformation of gingival fibroblast spheroids: potential utility for connective tissues regeneration.

    PubMed

    Kaufman, Gili; Whitescarver, Ryan; Nunes, Laiz; Palmer, Xavier-Lewis; Skrtic, Drago; Tutak, Wojtek

    2017-10-09

    Deep wounds in the gingiva caused by trauma or surgery require a rapid and robust healing of connective tissues. We propose utilizing gas-brushed nanofibers coated with collagen and fibrin for that purpose. Our hypotheses are that protein-coated nanofibers will: (i) attract and mobilize cells in various spatial orientations, and (ii) regulate the expression levels of specific extracellular matrix (ECM)-associated proteins, determining the initial conformational nature of dense and soft connective tissues. Gingival fibroblast monolayers and 3D spheroids were cultured on ECM substrate and covered with gas-blown poly-(DL-lactide-co-glycolide) (PLGA) nanofibers (uncoated/coated with collagen and fibrin). Cell attraction and rearrangement was followed by F-actin staining and confocal microscopy. Thicknesses of the cell layers, developed within the nanofibers, were quantified by imageJ software. The expression of collagen1α1 chain (Col1α1), fibronectin, and metalloproteinase 2 (MMP2) encoding genes was determined by quantitative reverse transcription analysis. Collagen- and fibrin- coated nanofibers induced cell migration toward fibers and supported cellular growth within the scaffolds. Both proteins affected the spatial rearrangement of fibroblasts by favoring packed cell clusters or intermittent cell spreading. These cell arrangements resembled the structural characteristic of dense and soft connective tissues, respectively. Within 3 days of incubation, fibroblast spheroids interacted with the fibers and grew robustly by increasing their thickness compared to monolayers. While the ECM key components, such as fibronectin and MMP2 encoding genes, were expressed in both protein groups, Col1α1 was predominantly expressed in bundled fibroblasts grown on collagen fibers. This enhanced expression of collagen1 is typical for dense connective tissue. Based on results of this study, our gas-blown, collagen- and fibrin-coated PLGA nanofibers are viable candidates for engineering soft and dense connective tissues with the required structural characteristics and functions needed for wound healing applications. Rapid regeneration of these layers should enhance healing of open wounds in a harsh oral environment. © 2017 IOP Publishing Ltd.

  3. Sugary interfaces mitigate contact damage where stiff meets soft

    PubMed Central

    Yoo, Hee Young; Iordachescu, Mihaela; Huang, Jun; Hennebert, Elise; Kim, Sangsik; Rho, Sangchul; Foo, Mathias; Flammang, Patrick; Zeng, Hongbo; Hwang, Daehee; Waite, J. Herbert; Hwang, Dong Soo

    2016-01-01

    The byssal threads of the fan shell Atrina pectinata are non-living functional materials intimately associated with living tissue, which provide an intriguing paradigm of bionic interface for robust load-bearing device. An interfacial load-bearing protein (A. pectinata foot protein-1, apfp-1) with L-3,4-dihydroxyphenylalanine (DOPA)-containing and mannose-binding domains has been characterized from Atrina's foot. apfp-1 was localized at the interface between stiff byssus and the soft tissue by immunochemical staining and confocal Raman imaging, implying that apfp-1 is an interfacial linker between the byssus and soft tissue, that is, the DOPA-containing domain interacts with itself and other byssal proteins via Fe3+–DOPA complexes, and the mannose-binding domain interacts with the soft tissue and cell membranes. Both DOPA- and sugar-mediated bindings are reversible and robust under wet conditions. This work shows the combination of DOPA and sugar chemistry at asymmetric interfaces is unprecedented and highly relevant to bionic interface design for tissue engineering and bionic devices. PMID:27305949

  4. Determination of the total acidity in soft drinks using potentiometric sequential injection titration.

    PubMed

    van Staden, J Koos F; Mashamba, M Mulalo G; Stefan, R Raluca I

    2002-12-06

    A potentiometric SI titration system for the determination of total acidity in soft drinks is proposed. The concept is based on the aspiration of the acid soft drink sample between two base zones into a holding coil with the volume of the first base zone twice to that of the second one and channelled by flow reversal through a reaction coil to a potentiometric sensor. A solution of 0.1 mol l(-1) sodium chloride is used as ionic strength adjustment buffer in the carrier stream. The system has been applied to the analysis of some South African soft drinks having a total acidity level of about 0.2-0.3% (w/v). The method has a sample frequency of 45 samples per h with a linear range of 0.1 and 0.6% (w/v). It is easy to use, fully computerised, and gives the results that are comparable to both automated batch titration and manual titration.

  5. Sugary interfaces mitigate contact damage where stiff meets soft

    NASA Astrophysics Data System (ADS)

    Yoo, Hee Young; Iordachescu, Mihaela; Huang, Jun; Hennebert, Elise; Kim, Sangsik; Rho, Sangchul; Foo, Mathias; Flammang, Patrick; Zeng, Hongbo; Hwang, Daehee; Waite, J. Herbert; Hwang, Dong Soo

    2016-06-01

    The byssal threads of the fan shell Atrina pectinata are non-living functional materials intimately associated with living tissue, which provide an intriguing paradigm of bionic interface for robust load-bearing device. An interfacial load-bearing protein (A. pectinata foot protein-1, apfp-1) with L-3,4-dihydroxyphenylalanine (DOPA)-containing and mannose-binding domains has been characterized from Atrina's foot. apfp-1 was localized at the interface between stiff byssus and the soft tissue by immunochemical staining and confocal Raman imaging, implying that apfp-1 is an interfacial linker between the byssus and soft tissue, that is, the DOPA-containing domain interacts with itself and other byssal proteins via Fe3+-DOPA complexes, and the mannose-binding domain interacts with the soft tissue and cell membranes. Both DOPA- and sugar-mediated bindings are reversible and robust under wet conditions. This work shows the combination of DOPA and sugar chemistry at asymmetric interfaces is unprecedented and highly relevant to bionic interface design for tissue engineering and bionic devices.

  6. Kerr microscopy study of exchange-coupled FePt/Fe exchange spring magnets

    NASA Astrophysics Data System (ADS)

    Hussain, Zaineb; Kumar, Dileep; Reddy, V. Raghavendra; Gupta, Ajay

    2017-05-01

    Magnetization reversal and magnetic microstructure of top soft magnetic layer (Fe) in exchange spring coupled L10 FePt/Fe is studied using high resolution Kerr microscopy. With remnant state of the hard magnetic layer (L10 FePt) as initial condition, magnetization loops along with magnetic domains are recorded for the top soft magnetic layer (Fe) using Kerr microscopy. Considerable shifting of Fe layer hysteresis loop from center which is similar to exchange bias phenomena is observed. It is also observed that one can tune the magnitude of hysteresis shift by reaching the remanent state from different saturating fields (HSAT) and also by varying the angle between measuring field and HSAT. The hysteresis loops and magnetic domains of top soft Fe layer demonstrate unambiguously that soft magnetic layer at remanent state in such exchange coupled system is having unidirectional anisotropy. An analogy is drawn and the observations are explained in terms of established model of exchange bias phenomena framed for field-cooled ferromagnetic - antiferromagnetic bilayer systems.

  7. Liquid chromatographic determination of L-ascorbic acid in candies and soft drinks.

    PubMed

    Maeda, Y; Ochi, S; Masui, T; Matubara, S

    1988-01-01

    The L-ascorbic acid (AsA) contents of candies and soft drinks available in the market were determined by liquid chromatography (LC). Samples are cleaned up on a disposable Sep-Pak C18 cartridge followed by reverse phase separation on an ODS column using a mobile phase of 0.1% phosphoric acid (pH 2.2). The AsA peak is detected on the basis of the UV absorption at 254 nm. The detection limit was 1 microgram/mL final concentration. Recoveries of AsA added at levels of 1-10 mg/g candy and 1-10 mg/10 mL soft drink were 99.2-101.7% with a coefficient of variation of 0.52-1.20% (n = 5). The present method allows rapid and accurate assays because it is a simple procedure compared with the official dye-titration method, and it is suitable for the routine analysis of AsA in selected candies and soft drinks.

  8. Reverse Current in Solar Flares

    NASA Technical Reports Server (NTRS)

    Knight, J. W., III

    1978-01-01

    An idealized steady state model of a stream of energetic electrons neutralized by a reverse current in the pre-flare solar plasma was developed. These calculations indicate that, in some cases, a significant fraction of the beam energy may be dissipated by the reverse current. Joule heating by the reverse current is a more effective mechanism for heating the plasma than collisional losses from the energetic electrons because the Ohmic losses are caused by thermal electrons in the reverse current which have much shorter mean free paths than the energetic electrons. The heating due to reverse currents is calculated for two injected energetic electron fluxes. For the smaller injected flux, the temperature of the coronal plasma is raised by about a factor of two. The larger flux causes the reverse current drift velocity to exceed the critical velocity for the onset of ion cyclotron turbulence, producing anomalous resistivity and an order of magnitude increase in the temperature. The heating is so rapid that the lack of ionization equilibrium may produce a soft X-ray and EUV pulse from the corona.

  9. Synchronous motor with soft start element formed between the motor rotor and motor output shaft to successfully synchronize loads that have high inertia and/or high torque

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

    Umans, Stephen D; Nisley, Donald L; Melfi, Michael J

    A line-start synchronous motor has a housing, a rotor shaft, and an output shaft. A soft-start coupling portion is operatively coupled to the output shaft and the rotor shaft. The soft-start coupling portion is configurable to enable the synchronous motor to obtain synchronous operation and to drive, at least near synchronous speed during normal steady state operation of the motor, a load having characteristics sufficient to prevent obtaining normal synchronous operation of the motor when the motor is operatively connected to the load in the absence of the soft-start coupling. The synchronous motor is sufficiently rated to obtain synchronous operationmore » and to drive, at least near synchronous speed during normal steady state operation of the motor, a load having characteristics sufficient to prevent obtaining normal synchronous operation of the motor when the motor is operatively connected to the load in the absence of the soft-start coupling.« less

  10. Going beyond Language: Soft Skill-ing Cultural Difference and Immigrant Integration in Toronto, Canada

    ERIC Educational Resources Information Center

    Allan, Kori

    2016-01-01

    This article traces how a language and soft skills training approach to Canadian immigrant integration emerged with Canada's shift towards a post-industrial tertiary economy. In this economy, soft skills index characteristics of ideal workers that fit the needs of Canada's post-Fordist labour regime. It examines how skills' training is not viewed…

  11. Design of a Soft Robot with Multiple Motion Patterns Using Soft Pneumatic Actuators

    NASA Astrophysics Data System (ADS)

    Miao, Yu; Dong, Wei; Du, Zhijiang

    2017-11-01

    Soft robots are made of soft materials and have good flexibility and infinite degrees of freedom in theory. These properties enable soft robots to work in narrow space and adapt to external environment. In this paper, a 2-DOF soft pneumatic actuator is introduced, with two chambers symmetrically distributed on both sides and a jamming cylinder along the axis. Fibers are used to constrain the expansion of the soft actuator. Experiments are carried out to test the performance of the soft actuator, including bending and elongation characteristics. A soft robot is designed and fabricated by connecting four soft pneumatic actuators to a 3D-printed board. The soft robotic system is then established. The pneumatic circuit is built by pumps and solenoid valves. The control system is based on the control board Arduino Mega 2560. Relay modules are used to control valves and pressure sensors are used to measure pressure in the pneumatic circuit. Experiments are conducted to test the performance of the proposed soft robot.

  12. Chromosome rearrangements in canine fibrosarcomas.

    PubMed

    Sargan, D R; Milne, B S; Hernandez, J Aguirre; O'Brien, P C M; Ferguson-Smith, M A; Hoather, T; Dobson, J M

    2005-01-01

    We have previously reported the use of six- and seven-color paint sets in the analysis of canine soft tissue sarcomas. Here we combine this technique with flow sorting of translocation chromosomes, reverse painting, and polymerase chain reaction (PCR) analysis of the gene content of the reverse paint in order to provide a more detailed analysis of cytogenetic abnormalities in canine tumors. We examine two fibrosarcomas, both from female Labrador retrievers, and show abnormalities in chromosomes 11 and 30 in both cases. Evidence of involvement of TGFBR1 is presented for one tumor.

  13. Dentinal tubules occluded by bioactive glass-containing toothpaste exhibit high resistance toward acidic soft drink challenge.

    PubMed

    Bakri, M M; Hossain, M Z; Razak, F A; Saqina, Z H; Misroni, A A; Ab-Murat, N; Kitagawa, J; Saub, R B

    2017-06-01

    Dentine hypersensitivity is a common problem attributed by patent dentinal tubules. Ingredients incorporated in toothpastes aim to occlude patent dentinal tubules to minimize the dentine hypersensitivity. However, frequent consumption of acidic soft drinks may reverse the dentinal tubules' occlusion. In this in vitro study, the efficacy of dentinal tubules occluded by commercially available toothpastes to withstand different durations of an acidic soft drink challenge was investigated. One hundred and twenty dentine discs were divided into three groups. The discs from each group were brushed with toothpaste containing bioactive glass, arginine and control toothpaste. Each group was then divided into four subgroups and exposed to acidic soft drink over four different time durations. The scoring and the percentage of occluded dentinal tubules by Novamin-containing toothpaste was significantly better compared with arginine or the control toothpaste. Acidic soft drink challenge reduced the extent of dentinal tubules occlusion along with time. Dentinal tubules occluded by Novamin-containing toothpaste withstand the acidic challenge comparatively for a longer period. The findings demonstrated that occlusion of dentinal tubules is more efficient by the bioactive glass-containing toothpaste and thus may contribute to its better resistance to acidic soft drink challenge. © 2016 Australian Dental Association.

  14. Effects of nuclear radiation on a high-reliability silicon power diode. 4: Analysis of reverse bias characteristics

    NASA Technical Reports Server (NTRS)

    Been, J. F.

    1973-01-01

    The effects of nuclear radiation on the reverse bias electrical characteristics of one hundred silicon power diodes were investigated. On a percentage basis, the changes in reverse currents were large but, due to very low initial values, this electrical characteristic was not the limiting factor in use of these diodes. These changes were interpreted in terms of decreasing minority carrier lifetimes as related to generation-recombination currents. The magnitudes of reverse voltage breakdown were unaffected by irradiation.

  15. Physical Properties and Stability of Soft Gelled Chitosan-Based Nanoparticles.

    PubMed

    Goycoolea, Francisco M; Brunel, Fabrice; Gueddari, Nour E El; Coggiola, Anna; Lollo, Giovanna; Moerschbacher, Bruno M; Remuñán-López, Carmen; Delair, Thierry; Domard, Alain; Alonso, María J

    2016-12-01

    We addressed the role of the degree of acetylation (DA) and of M w of chitosan (CS) on the physical characteristics and stability of soft nanoparticles obtained through either ionic cross-linking with sodium tripolyphosphate (TPP), or reverse emulsion/gelation. Each of these methods affords nanoparticles (NPs) or nanogels (NGs), respectively. The size of CS-TPP NPs comprising CS of high M w (≈123-266 kDa) increases with DA (≈1.6%-56%), while it do not change for CS of low M w (≈11-13 kDa); the zeta potential (ζ) decreases with DA regardless of M w (ζ ≈+34.6 ± 2.6 to ≈+25.2 + 0.6 mV) and the NPs appear as spheres in transmission electron microscopy. Stability in various cell culture media (pH 7.4 at 37 °C) is greater for NPs made with CS of DA ≥ 27%. In turn, NGs exhibit larger sizes (520 ± 32 to 682 ± 27 nm) than do CS-TPP NPs, and can only be formed with CS of DA < 30%. The average diameter size for these NGs shows a monotonic increase with CS's M w . The physical properties and stability of these systems in biological media depend mostly on the DA of CS and its influence on the balance between hydrophilic/hydrophobic interactions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Abundance and physiology of dominant soft corals linked to water quality in Jakarta Bay, Indonesia

    PubMed Central

    Januar, Indra; Wild, Christian; Kunzmann, Andreas

    2016-01-01

    Declining water quality is one of the main reasons of coral reef degradation in the Thousand Islands off the megacity Jakarta, Indonesia. Shifts in benthic community composition to higher soft coral abundances have been reported for many degraded reefs throughout the Indo-Pacific. However, it is not clear to what extent soft coral abundance and physiology are influenced by water quality. In this study, live benthic cover and water quality (i.e. dissolved inorganic nutrients (DIN), turbidity (NTU), and sedimentation) were assessed at three sites (< 20 km north of Jakarta) in Jakarta Bay (JB) and five sites along the outer Thousand Islands (20–60 km north of Jakarta). This was supplemented by measurements of photosynthetic yield and, for the first time, respiratory electron transport system (ETS) activity of two dominant soft coral genera, Sarcophyton spp. and Nephthea spp. Findings revealed highly eutrophic water conditions in JB compared to the outer Thousand Islands, with 44% higher DIN load (7.65 μM/L), 67% higher NTU (1.49 NTU) and 47% higher sedimentation rate (30.4 g m−2 d−1). Soft corals were the dominant type of coral cover within the bay (2.4% hard and 12.8% soft coral cover) compared to the outer Thousand Islands (28.3% hard and 6.9% soft coral cover). Soft coral abundances, photosynthetic yield, and ETS activity were highly correlated with key water quality parameters, particularly DIN and sedimentation rates. The findings suggest water quality controls the relative abundance and physiology of dominant soft corals in JB and may thus contribute to phase shifts from hard to soft coral dominance, highlighting the need to better manage water quality in order to prevent or reverse phase shifts. PMID:27904802

  17. Rearrangements and Yielding in Concentrated Suspensions of Hard and Soft Colloids

    NASA Astrophysics Data System (ADS)

    Petekidis, Georgios; Carrier, Vincent; Vlassoppoulos, Dimitris; Pusey, Peter; Ballauff, Matthias

    2004-03-01

    The rheology and microscopic particle rearrangements of concentrated colloidal suspensions were studied by a combination of conventional rheology and Light Scattering under shear (LS Echo). In particular we studied the rheological response and the microscopic particle dynamics under shear near and above the glass transitions concentration. Measurements were done in model hard and soft sphere particles (sterically stabilized PMMA and PS-PNIPA microgels respectively) to assess the effect of inter-particle interactions. Creep and recovery measurements and dynamic strain sweeps showed that glasses of hard particles can tolerate surprisingly large strains, up to at least 15probes the extent of irreversible particle rearrangement under oscillatory shear, verified that within their cage particles move reversibly at least up to such a strain. Such a behavior was attributed to 'cage elasticity', the ability of a particle and its neighbors to retain their relative positions within the cage under quite large distortion [1]. The onset of irreversible rearrangements measured by LS echo decreased with decreasing frequency revealing an interplay between shear and Brownian forces. The effects of interparticle interactions were studied using soft thermoreversible migrogel particles where a glass state may be reached either increasing the particle concentration or decreasing the temperature. Here, although particle rearrangements appear to be reversible up to strains as high as 100sweep is observed at much lower strains. [1] G. Petekidis, D. Vlassopoulos and P.N. Pusey, Faraday Discuss., 123, 287 (2003)

  18. Hydrogel Walkers with Electro-Driven Motility for Cargo Transport.

    PubMed

    Yang, Chao; Wang, Wei; Yao, Chen; Xie, Rui; Ju, Xiao-Jie; Liu, Zhuang; Chu, Liang-Yin

    2015-08-28

    In this study, soft hydrogel walkers with electro-driven motility for cargo transport have been developed via a facile mould-assisted strategy. The hydrogel walkers consisting of polyanionic poly(2-acrylamido-2-methylpropanesulfonic acid-co-acrylamide) exhibit an arc looper-like shape with two "legs" for walking. The hydrogel walkers can reversibly bend and stretch via repeated "on/off" electro-triggers in electrolyte solution. Based on such bending/stretching behaviors, the hydrogel walkers can move their two "legs" to achieve one-directional walking motion on a rough surface via repeated "on/off" electro-triggering cycles. Moreover, the hydrogel walkers loaded with very heavy cargo also exhibit excellent walking motion for cargo transport. Such hydrogel systems create new opportunities for developing electro-controlled soft systems with simple design/fabrication strategies in the soft robotic field for remote manipulation and transportation.

  19. A multi-frame soft x-ray pinhole imaging diagnostic for single-shot applications

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

    Wurden, G. A.; Coffey, S. K.

    2012-10-15

    For high energy density magnetized target fusion experiments at the Air Force Research Laboratory FRCHX machine, obtaining multi-frame soft x-ray images of the field reversed configuration (FRC) plasma as it is being compressed will provide useful dynamics and symmetry information. However, vacuum hardware will be destroyed during the implosion. We have designed a simple in-vacuum pinhole nosecone attachment, fitting onto a Conflat window, coated with 3.2 mg/cm{sup 2} of P-47 phosphor, and covered with a thin 50-nm aluminum reflective overcoat, lens-coupled to a multi-frame Hadland Ultra intensified digital camera. We compare visible and soft x-ray axial images of translating ({approx}200more » eV) plasmas in the FRX-L and FRCHX machines in Los Alamos and Albuquerque.« less

  20. Characteristic Examination of New Synchronous Motor that Composes Craw Teeth of Soft Magnetic Composite

    NASA Astrophysics Data System (ADS)

    Enomoto, Yuji; Ito, Motoya; Masaki, Ryozo; Asaka, Kazuo

    We examined the claw type teeth motor as one application of the soft magnetic composite to a motor core. In order to understand quantitatively the characteristics of the claw type teeth motor, we used the 3-dimensional electromagnetic field analysis to predict its characteristics in advance and manufactured a trial motor to estimate it. And we examined the advantages of the claw type teeth motor comparing with a conventional slot type motor. The results are: 1. By using the 3-dimensional electromagnetic field analysis, it is able to estimate with high accuracy the characteristics of the 3-phase permanent magnet synchronous claw type teeth motor having a core composed of the soft magnetic composite. 2. The claw type teeth motor is able to achieve about 20% higher output than a conventional slot type motor having an electromagnetic steel core, while both volumes are equal. 3. The motor efficiency of the claw type teeth motor is about 3.5% higher than the conventional motor.

  1. Non Lipomatous Benign Lesions Mimicking Soft-tissue Sarcomas: A Pictorial Essay

    PubMed Central

    CORAN, ALESSANDRO; ORSATTI, GIOVANNA; CRIMÌ, FILIPPO; RASTRELLI, MARCO; DI MAGGIO, ANTONIO; PONZONI, ALBERTO; ATTAR, SHADY; STRAMARE, ROBERTO

    2018-01-01

    The incidental finding of soft tissue masses is a challenge for the radiologist. Benign and malignant lesions can be differentiated relying on patient history, symptoms and mostly with the help of imaging. Ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) become fundamental in order to distinguish these lesions but the radiologist needs to know the main characteristics of benign soft tissue masses and sarcomas. Herein, we present a pictorial review of lesions mimicking soft tissue sarcomas features. PMID:29475903

  2. Soft grippers using micro-fibrillar adhesives for transfer printing.

    PubMed

    Song, Sukho; Sitti, Metin

    2014-07-23

    The adhesive characteristics of fibrillar adhesives on a soft deformable membrane are reported. A soft gripper with an inflatable membrane covered by elastomer mushroom-shaped microfibers have a superior conformation to non-planar 3D part geometries, enabling the transfer printing of various parts serially or in parallel. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Importance of core electrostatic properties on the electrophoresis of a soft particle

    NASA Astrophysics Data System (ADS)

    De, Simanta; Bhattacharyya, Somnath; Gopmandal, Partha P.

    2016-08-01

    The impact of the volumetric charged density of the dielectric rigid core on the electrophoresis of a soft particle is analyzed numerically. The volume charge density of the inner core of a soft particle can arise for a dendrimer structure or bacteriophage MS2. We consider the electrokinetic model based on the conservation principles, thus no conditions for Debye length or applied electric field is imposed. The fluid flow equations are coupled with the ion transport equations and the equation for the electric field. The occurrence of the induced nonuniform surface charge density on the outer surface of the inner core leads to a situation different from the existing analysis of a soft particle electrophoresis. The impact of this induced surface charge density together with the double-layer polarization and relaxation due to ion convection and electromigration is analyzed. The dielectric permittivity and the charge density of the core have a significant impact on the particle electrophoresis when the Debye length is in the order of the particle size. We find that by varying the ionic concentration of the electrolyte, the particle can exhibit reversal in its electrophoretic velocity. The role of the polymer layer softness parameter is addressed in the present analysis.

  4. Extending of flat normal dispersion profile in all-solid soft glass nonlinear photonic crystal fibres

    NASA Astrophysics Data System (ADS)

    Siwicki, Bartłomiej; Kasztelanic, Rafał; Klimczak, Mariusz; Cimek, Jarosław; Pysz, Dariusz; Stępień, Ryszard; Buczyński, Ryszard

    2016-06-01

    The bandwidth of coherent supercontinuum generated in optical fibres is strongly determined by the all-normal dispersion characteristic of the fibre. We investigate all-normal dispersion limitations in all-solid oxide-based soft glass photonic crystal fibres with various relative inclusion sizes and lattice constants. The influence of material dispersion on fibre dispersion characteristics for a selected pair of glasses is also examined. A relation between the material dispersion of the glasses and the fibre dispersion has been described. We determined the parameters which limit the maximum range of flattened all-normal dispersion profile achievable for the considered pair of heavy-metal-oxide soft glasses.

  5. Magnetization reversal mechanisms in hybrid resin-bonded Nd Fe B magnets

    NASA Astrophysics Data System (ADS)

    Plusa, D.; Dospial, M.; Slusarek, B.; Kotlarczyk, U.

    2006-11-01

    The magnetic properties of isotropic epoxy resin-bonded magnets prepared by mixing a hard magnetic powder made from melt quenched Nd-Fe-Co-B ribbons and a soft magnetic iron powder have been examined. The magnetization reversal processes and the magnetic parameters have been studied by the measurement of the virgin magnetization curves, the major and minor hysteresis loops and sets of recoil curves. From these recoil curves the field dependence of the reversible and irreversible magnetization components during the magnetization and demagnetization processes has been derived. The remanence relationship was used to study the nature of magnetic interaction between the grains. A study of interaction domains was conducted using optical microscopy. Groups of domains, each over several grains, were observed. It was found that the reversal process in the samples investigated involves the rotation of magnetization vectors in the iron powder grains and pinning of domain walls at the MQP-B grain boundaries.

  6. Soft drinks consumption and child behaviour problems: the role of food insecurity and sleep patterns.

    PubMed

    King, Christian

    2017-02-01

    To examine whether the association between soft drinks consumption and child behaviour problems differs by food security status and sleep patterns in young children. Cross-sectional observational data from the Fragile Families and Child Wellbeing Study (FFCWS), which collected information on food insecurity, soft drinks consumption, sleep patterns and child behaviour problems. Bivariate and multivariate ordinary least-squares regression analyses predicting child behaviour problems and accounting for socio-economic factors and household characteristics were performed. Twenty urban cities in the USA with a population of 200 000 or more. Parental interviews of 2829 children who were about 5 years old. Soft drinks consumption was associated with aggressive behaviours, withdrawn and attention problems for children aged 5 years. However, the association differed by food security status. The association was mostly statistically insignificant among food-secure children after accounting for socio-economic and demographic characteristics. On the other hand, soft drinks consumption was associated with behaviour problems for food-insecure children even after accounting for these factors. However, after accounting for child sleep patterns, the association between soft drinks consumption and child behaviour problems became statistically insignificant for food-insecure children. The negative association between soft drinks consumption and child behaviour problems could be explained by sleep problems for food-insecure children. Since about 21 % of households with children are food insecure, targeted efforts to reduce food insecurity would help improve dietary (reduce soft drinks consumption) and health behaviours (improve sleep) and reduce child behaviour problems.

  7. Soft x-ray pinhole imaging diagnostics for compact toroid plasmas

    NASA Astrophysics Data System (ADS)

    Crawford, E. A.; Taggart, D. P.; Bailey, A. D., III

    1990-10-01

    Soft x-ray pinhole imaging has recently become established as a valuable diagnostic for visualization of field reversed configuration (FRC) plasmas in the TRX-2, FRX-C/LSM devices. Gated MCP image converter devices with CsI cathodes and Be filters with a peak response around 11 nm wavelength are used for exposure durations ranging from a few tenths up to several microseconds. Results of experiments with single and Chevron channel plates are discussed along with estimates of linear exposure limitations with both film and CCD cameras as recording media. Plans for multiframe devices on the FRX-C/LSM and the LSX devices are also discussed.

  8. Practical use of imaging technique for management of bone and soft tissue tumors.

    PubMed

    Miwa, Shinji; Otsuka, Takanobu

    2017-05-01

    Imaging modalities including radiography, computed tomography (CT), and magnetic resonance imaging (MRI) are necessary for the diagnosis of bone and soft tissue tumors. The history of imaging began with the discovery of X-rays in the 19th century. The development of CT, MRI, ultrasonography, and positron emission tomography (PET) have improved the management of bone and soft tissue tumors. X-ray imaging and CT scans enable the evaluation of bone destruction, periosteal reaction, sclerotic changes in lesions, condition of cortical bone, and ossification. MRI enables the assessment of tissue characteristics, tumor extent, and the reactive areas. Functional imaging modalities including 201 thallium ( 201 Tl) scintigraphy can be used to differentiate benign lesions from malignant lesions and to assess chemotherapeutic effects. Real-time assessment of soft tissue tumors by ultrasonography enables accurate and safe performance of surgery and biopsy. This article describes useful imaging modalities and characteristic findings in the management of bone and soft tissue tumors. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  9. Allograft-prosthetic composite reverse total shoulder arthroplasty for reconstruction of proximal humerus tumor resections.

    PubMed

    King, Joseph J; Nystrom, Lukas M; Reimer, Nickolas B; Gibbs, C Parker; Scarborough, Mark T; Wright, Thomas W

    2016-01-01

    Proximal humerus reconstructions after resection of tumors are challenging. Early success of the reverse shoulder arthroplasty for reconstructions has recently been reported. The reverse allograft-prosthetic composite offers the advantage of improved glenohumeral stability compared with hemiarthroplasty for proximal humeral reconstructions as it uses the deltoid for stability. This article describes the technique for treating proximal humeral tumors, including preoperative planning, biopsy principles, resection pearls, soft tissue tensioning, and specifics about reconstruction using the reverse allograft-prosthetic composite. Two cases are presented along with the functional outcomes with use of this technique. Biomechanical considerations during reconstruction are reviewed, including techniques to improve the deltoid compression force. Reported instability rates are less with reverse shoulder arthroplasty reconstruction as opposed to hemiarthroplasty or total shoulder arthroplasty reconstructions of tumor resections. Reported functional outcomes are promising for the reverse allograft-prosthetic composite reconstructions, although complications are reported. Reverse allograft-prosthetic composites are a promising option for proximal humeral reconstructions, although nonunion of the allograft-host bone junction continues to be a challenge for this technique. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  10. Genetic networks and soft computing.

    PubMed

    Mitra, Sushmita; Das, Ranajit; Hayashi, Yoichi

    2011-01-01

    The analysis of gene regulatory networks provides enormous information on various fundamental cellular processes involving growth, development, hormone secretion, and cellular communication. Their extraction from available gene expression profiles is a challenging problem. Such reverse engineering of genetic networks offers insight into cellular activity toward prediction of adverse effects of new drugs or possible identification of new drug targets. Tasks such as classification, clustering, and feature selection enable efficient mining of knowledge about gene interactions in the form of networks. It is known that biological data is prone to different kinds of noise and ambiguity. Soft computing tools, such as fuzzy sets, evolutionary strategies, and neurocomputing, have been found to be helpful in providing low-cost, acceptable solutions in the presence of various types of uncertainties. In this paper, we survey the role of these soft methodologies and their hybridizations, for the purpose of generating genetic networks.

  11. Auxiliary quasi-resonant dc tank electrical power converter

    DOEpatents

    Peng, Fang Z.

    2006-10-24

    An auxiliary quasi-resonant dc tank (AQRDCT) power converter with fast current charging, voltage balancing (or charging), and voltage clamping circuits is provided for achieving soft-switched power conversion. The present invention is an improvement of the invention taught in U.S. Pat. No. 6,111,770, herein incorporated by reference. The present invention provides faster current charging to the resonant inductor, thus minimizing delay time of the pulse width modulation (PWM) due to the soft-switching process. The new AQRDCT converter includes three tank capacitors or power supplies to achieve the faster current charging and minimize the soft-switching time delay. The new AQRDCT converter further includes a voltage balancing circuit to charge and discharge the three tank capacitors so that additional isolated power supplies from the utility line are not needed. A voltage clamping circuit is also included for clamping voltage surge due to the reverse recovery of diodes.

  12. Analysis of Soft Drinks: UV Spectrophotometry, Liquid Chromatography, and Capillary Electrophoresis

    NASA Astrophysics Data System (ADS)

    McDevitt, Valerie L.; Rodriguez, Alejandra; Williams, Kathryn R.

    1998-05-01

    Instrumental analysis students analyze commercial soft drinks in three successive laboratory experiments. First, UV multicomponent analysis is used to determine caffeine and benzoic acid in Mello YelloTM using the spectrophotometer's software and manually by the simultaneous equations method. The following week, caffeine, benzoic acid and aspartame are determined in a variety of soft drinks by reversed-phase liquid chromatography using 45% methanol/55% aqueous phosphate, pH 3.0, as the mobile phase. In the third experiment, the same samples are analyzed by capillary electrophoresis using a pH 9.4 borate buffer. Students also determine the minimum detection limits for all three compounds by both LC and CE. The experiments demonstrate the analytical use and limitations of the three instruments. The reports and prelab quizzes also stress the importance of the chemistry of the three compounds, especially the relationships of acid/base behavior and polarity to the LC and CE separations.

  13. Interplay of soft and perturbative correlations in multiparton interactions at central rapidities

    DOE PAGES

    Blok, B.; Strikman, M.

    2017-06-22

    We study the role of soft/nonperturbative correlations in the multi parton interactions in the central kinematics relevant for double parton scattering (DPS) and underlying event (UE) measurements at ATLAS and CMS. We show that the effect of soft correlations is negligible for DPS regime (typical transverse momenta larger than 10–20 GeV), but may be important for UE (several GeV scale). The characteristic scale where soft correlations become important increases with decrease of x (energy increase) leading to approximately constant σ eff at small x.

  14. Interplay of soft and perturbative correlations in multiparton interactions at central rapidities

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

    Blok, B.; Strikman, M.

    We study the role of soft/nonperturbative correlations in the multi parton interactions in the central kinematics relevant for double parton scattering (DPS) and underlying event (UE) measurements at ATLAS and CMS. We show that the effect of soft correlations is negligible for DPS regime (typical transverse momenta larger than 10–20 GeV), but may be important for UE (several GeV scale). The characteristic scale where soft correlations become important increases with decrease of x (energy increase) leading to approximately constant σ eff at small x.

  15. Sperm characteristics and teratology in rats following vas deferens occlusion with RISUG and its reversal.

    PubMed

    Lohiya, N K; Suthar, R; Khandelwal, A; Goyal, S; Ansari, A S; Manivannan, B

    2010-02-01

    The functional success of the reversal of vas occlusion by styrene maleic anhydride (RISUG), using the solvent vehicle, Dimethyl Sulphoxide (DMSO), has been investigated. Reversal with DMSO was carried out in Wistar albino rats 90 days after bilateral vas occlusion. The body weight, organ weight, sperm characteristics, fertility test and teratology, including skeletal morphology were evaluated in vas occlusion and reversal animals and in F(1) progenies to assess the functional success of the occlusion and reversal. Body weight, organ weight and the cauda epididymal sperm characteristics of vas occlusion and reversal animals and of F(1) progenies were comparable to control. Ejaculated spermatozoa in the vaginal smear showed detached head/tail, acrosomal damage, bent midpiece, bent tail and morphological aberrations in sperm head after vas occlusion, which returned to normal, 90 days after reversal. Monthly fertility test, post-injection showed 0% fertility, which improved gradually and 100% fertility was achieved 90 days after reversal. The fertility/pregnancy/implantation record and skeletal morphology of the offspring were comparable to control. The results suggest functional success and safety of vas occlusion reversal by DMSO.

  16. Support effects in single atom iron catalysts on adsorption characteristics of toxic gases (NO2, NH3, SO3 and H2S)

    NASA Astrophysics Data System (ADS)

    Gao, Zhengyang; Yang, Weijie; Ding, Xunlei; Lv, Gang; Yan, Weiping

    2018-04-01

    The effects of support on gas adsorption is crucial for single atom catalysts design and optimization. To gain insight into support effects on gas adsorption characteristics, a comprehensive theoretical study was performed to investigate the adsorption characteristics of toxic gases (NO2, NH3, SO3 and H2S) by utilizing single atom iron catalysts with three graphene-based supports. The adsorption geometry, adsorption energy, electronic and magnetic properties of the adsorption system have been explored. Additionally, the support effects have been analyzed through d-band center and Fermi softness, and thermodynamic analysis has been performed to consider the effect of temperature on gas adsorption. The support effects have a remarkable influence on the adsorption characteristics of four types of toxic gases which is determined by the electronic structure of graphene-based support, and the electronic structure can be characterized by Fermi softness of catalysts. Fermi softness and uplift height of Fe atom could be good descriptors for the adsorption activity of single atom iron catalysts with graphene-based supports. The findings can lay a foundation for the further study of graphene-based support effects in single atom catalysts and provide a guideline for development and design of new graphene-based support materials utilizing the idea of Fermi softness.

  17. Research on Colorant Systems Whose Characteristics May Be Reversed

    DTIC Science & Technology

    1974-06-01

    U.S. DEPARTMENT OF COMMERCE NatioMl Technical Information Service AD-A024 083 RESEARCH ON COLORANT SYSTEMS WHOSE CHARACTERISTICS MAY BE REVERSED...TR 75-61-CEMEL 2. SOVT ACCESSION NO «■ TITLE (on* SuMtl») RESEARCH ON COLORANT SYSTEMS WHOSE CHARACTERISTICS MAY BE REVERSED T. AUTMONM...estigation of electrically operated color- ant systems by which the color of a surface could be changed in a controlled manner. Four basic

  18. A Novel Approach for Reconstruction of Finger Neurocutaneous Defect: A Sensory Reverse Dorsal Digital Artery Flap from the Neighboring Digit.

    PubMed

    Feng, Shi-Ming; Sun, Qing-Qing; Cheng, Jian; Wang, Ai-Guo

    2017-11-01

    Providing soft tissue coverage for finger neurocutaneous defects presents aesthetic and sensory challenges. A common source for reconstruction of soft tissue defects of the fingers is the same finger. However, when the donor areas are damaged by concomitant injuries, this option is not available. The present study aims to reconstruct finger neurocutaneous defects using a sensory reverse dorsal digital artery flap from the neighboring digit and to evaluate the efficacy of this technique. The study included 16 patients, with an average age of 34.9 years (range, 20-53 years) at the time of surgery, from May 2010 to June 2013. The sensory reverse dorsal digital artery flap was used in all 16 patients, who had a combination of soft tissue and digital nerve defects. The mean size of the soft tissue defects was 3.1 cm × 2.0 cm, and the mean flap size was 3.3 cm × 2.2 cm. The length of the nerve defects ranged from 1.3 to 2.5 cm (mean, 2.0 cm), which were reconstructed with dorsal branches of the proper digital nerve transfer. The active motion of the fingers (injured and donor) and the flap sensibility (static two-point discrimination) were measured. The appearance and functional recovery of the injured finger and the donor site were assessed using the Michigan Hand Outcomes Questionnaire. All flaps survived completely. No complications were reported, and no further flap debulking procedure was required. At the mean follow-up period of 24 months (range, 18-30 months), the mean static two-point discrimination was 6.5 mm (range, 5-10 mm) of the reconstructed area; the mean ranges of motions of the injured finger and the opposite finger at the proximal interphalangeal and distal interphalangeal joints were 102.2° and 103.5°, and 70.3° and 76.5°, respectively. The average ranges of motions of the metacarpophalangeal and proximal interphalangeal joints of the donor fingers were 90° and 103.4°, respectively. Based on the Michigan Hand Outcomes Questionnaire, 10 patients were strongly satisfied and 6 were satisfied with the functional recovery of the injured finger; however, 13 patients were strongly satisfied and 3 were satisfied with the appearance of the injured finger. The sensory reverse dorsal digital artery flap from the neighboring digit, based on the dorsal branch of the digital artery, is an effective and additional option for finger neurocutaneous defect reconstruction when use of the local and regional flaps is not feasible. © 2017 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

  19. Basis for selecting soft wheat for end-use quality

    USDA-ARS?s Scientific Manuscript database

    Within the United States, end-use quality of soft wheat (Triticum aestivum L.) is determined by several genetically controlled components: milling yield, flour particle size, and baking characteristics related to flour water absorption caused by glutenin macropolymer, non-starch polysaccharides, and...

  20. Measurements of hot electrons in the Extrap T1 reversed-field pinch

    NASA Astrophysics Data System (ADS)

    Welander, A.; Bergsåker, H.

    1998-02-01

    The presence of an anisotropic energetic electron population in the edge region is a characteristic feature of reversed-field pinch (RFP) plasmas. In the Extrap T1 RFP, the anisotropic, parallel heat flux in the edge region measured by calorimetry was typically several hundred 0741-3335/40/2/011/img1. To gain more insight into the origin of the hot electron component and to achieve time resolution of the hot electron flow during the discharge, a target probe with a soft x-ray monitor was designed, calibrated and implemented. The x-ray emission from the target was measured with a surface barrier detector covered with a set of different x-ray filters to achieve energy resolution. A calibration in the range 0.5-2 keV electron energy was performed on the same target and detector assembly using a 0741-3335/40/2/011/img2 cathode electron gun. The calibration data are interpolated and extrapolated numerically. A directional asymmetry of more than a factor of 100 for the higher energy electrons is observed. The hot electrons are estimated to constitute 10% of the total electron density at the edge and their energy distribution is approximated by a half-Maxwellian with a temperature slightly higher than the central electron temperature. Scalings with plasma current, as well as correlations with local 0741-3335/40/2/011/img3 measurements and radial dependences, are presented.

  1. Thermal stability and temperature coefficients of four rare-earth-cobalt matrix magnets heated in dry air

    NASA Astrophysics Data System (ADS)

    Strnat, R. M. W.; Liu, S.; Strnat, K. J.

    1982-03-01

    Flux-loss characteristics during long-term air aging of four rare-earth-cobalt matrix magnet types were measured. Irreversible losses and reversible temperature coefficients on heating above room temperature are reported. Purely magnetic and permanent microstructure-related changes during aging were differentiated by measuring hysteresis curves before and after long-term exposure. Three commercial polymer-bonded magnets using different rare-earth-cobalt-transition metal alloys and a solder-matrix magnet with Sm(Co, Cu, Fe, Zr)7.4 were studied. They were cycled between 25 °C and maximum temperatures to 150 °C (25 ° intervals) as applicable. Aging data at 50 and 125 °C for an exposure time of 3300 h are reported. The 2-17 samples have a stability far superior to bonded 1-5. The soft metal binder imparts significantly better aging behavior on precipitation-hardened 2-17 magnet alloys above 100 °C than an epoxy resin matrix.

  2. Detection of SYT-SSX mutant transcripts in formalin-fixed paraffin-embedded sarcoma tissues using one-step reverse transcriptase real-time PCR.

    PubMed

    Norlelawati, A T; Mohd Danial, G; Nora, H; Nadia, O; Zatur Rawihah, K; Nor Zamzila, A; Naznin, M

    2016-04-01

    Synovial sarcoma (SS) is a rare cancer and accounts for 5-10% of adult soft tissue sarcomas. Making an accurate diagnosis is difficult due to the overlapping histological features of SS with other types of sarcomas and the non-specific immunohistochemistry profile findings. Molecular testing is thus considered necessary to confirm the diagnosis since more than 90% of SS cases carry the transcript of t(X;18)(p11.2;q11.2). The purpose of this study is to diagnose SS at molecular level by testing for t(X;18) fusion-transcript expression through One-step reverse transcriptase real-time Polymerase Chain Reaction (PCR). Formalin-fixed paraffin-embedded tissue blocks of 23 cases of soft tissue sarcomas, which included 5 and 8 cases reported as SS as the primary diagnosis and differential diagnosis respectively, were retrieved from the Department of Pathology, Tengku Ampuan Afzan Hospital, Kuantan, Pahang. RNA was purified from the tissue block sections and then subjected to One-step reverse transcriptase real-time PCR using sequence specific hydrolysis probes for simultaneous detection of either SYT-SSX1 or SYT-SSX2 fusion transcript. Of the 23 cases, 4 cases were found to be positive for SYT-SSX fusion transcript in which 2 were diagnosed as SS whereas in the 2 other cases, SS was the differential diagnosis. Three cases were excluded due to failure of both amplification assays SYT-SSX and control β-2-microglobulin. The remaining 16 cases were negative for the fusion transcript. This study has shown that the application of One-Step reverse transcriptase real time PCR for the detection SYT-SSX transcript is feasible as an aid in confirming the diagnosis of synovial sarcoma.

  3. Calculated Dynamic Characteristics of a Soft-Inplane Hingeless Rotor Helicopter

    NASA Technical Reports Server (NTRS)

    Johnson, W.

    1977-01-01

    Calculated dynamic characteristics of a representative soft-inplane hingeless rotor helicopter are presented. The flight dynamics as a function of speed and gross weight are given. The requirements for accurate analytical modelling of this helicopter are established. The influence of the horizontal tail size, the rotor precone, the blade sweep, and the blade center of gravity/aerodynamic center offset on the calculated flight dynamics and aeroelastic stability are examined. The calculations show no evidence of an air resonance stability problem with this aircraft.

  4. Small-scale soft-bodied robot with multimodal locomotion.

    PubMed

    Hu, Wenqi; Lum, Guo Zhan; Mastrangeli, Massimo; Sitti, Metin

    2018-02-01

    Untethered small-scale (from several millimetres down to a few micrometres in all dimensions) robots that can non-invasively access confined, enclosed spaces may enable applications in microfactories such as the construction of tissue scaffolds by robotic assembly, in bioengineering such as single-cell manipulation and biosensing, and in healthcare such as targeted drug delivery and minimally invasive surgery. Existing small-scale robots, however, have very limited mobility because they are unable to negotiate obstacles and changes in texture or material in unstructured environments. Of these small-scale robots, soft robots have greater potential to realize high mobility via multimodal locomotion, because such machines have higher degrees of freedom than their rigid counterparts. Here we demonstrate magneto-elastic soft millimetre-scale robots that can swim inside and on the surface of liquids, climb liquid menisci, roll and walk on solid surfaces, jump over obstacles, and crawl within narrow tunnels. These robots can transit reversibly between different liquid and solid terrains, as well as switch between locomotive modes. They can additionally execute pick-and-place and cargo-release tasks. We also present theoretical models to explain how the robots move. Like the large-scale robots that can be used to study locomotion, these soft small-scale robots could be used to study soft-bodied locomotion produced by small organisms.

  5. Small-scale soft-bodied robot with multimodal locomotion

    NASA Astrophysics Data System (ADS)

    Hu, Wenqi; Lum, Guo Zhan; Mastrangeli, Massimo; Sitti, Metin

    2018-02-01

    Untethered small-scale (from several millimetres down to a few micrometres in all dimensions) robots that can non-invasively access confined, enclosed spaces may enable applications in microfactories such as the construction of tissue scaffolds by robotic assembly, in bioengineering such as single-cell manipulation and biosensing, and in healthcare such as targeted drug delivery and minimally invasive surgery. Existing small-scale robots, however, have very limited mobility because they are unable to negotiate obstacles and changes in texture or material in unstructured environments. Of these small-scale robots, soft robots have greater potential to realize high mobility via multimodal locomotion, because such machines have higher degrees of freedom than their rigid counterparts. Here we demonstrate magneto-elastic soft millimetre-scale robots that can swim inside and on the surface of liquids, climb liquid menisci, roll and walk on solid surfaces, jump over obstacles, and crawl within narrow tunnels. These robots can transit reversibly between different liquid and solid terrains, as well as switch between locomotive modes. They can additionally execute pick-and-place and cargo-release tasks. We also present theoretical models to explain how the robots move. Like the large-scale robots that can be used to study locomotion, these soft small-scale robots could be used to study soft-bodied locomotion produced by small organisms.

  6. Effect of sodium chloride and sodium bicarbonate on the physicochemical properties of soft wheat flour doughs and gluten polymerization.

    PubMed

    Chen, Gengjun; Ehmke, Laura; Miller, Rebecca; Faa, Pierre; Smith, Gordon; Li, Yonghui

    2018-06-07

    Soft wheat flour doughs were prepared with different levels of salt (NaCl) and/or baking soda (NaHCO3). Oscillation rheology, elongational viscosity, and extensibility of doughs were tested to evaluate the effect of salt and/or baking soda on the physical properties of doughs. Furthermore, a series of physical-biochemical analytical techniques were used to investigate gluten polymerization in doughs, including Zeta potential analyzer, Fourier transform infrared spectroscopy (FTIR), spectrophotometer, and reversed phase high performance liquid chromatography (RP-HPLC). Addition of high levels of NaHCO3 (1.0 % fwb), either by itself or in combination with NaCl, increased dough strength, elongational viscosity, and viscoelasticity. RP-HPLC results demonstrated macromolecular aggregation of gluten proteins in the presence of NaCl and/or NaHCO3. Addition of NaHCO3 or NaCl also decreased both free sulfhydryl content and random coil structure of gluten isolated from the doughs. Overall, NaCl and/or NaHCO3 induced the changes of molecular conformation of gluten, which impacted the physicochemical qualities of soft wheat flour dough. Our study provides a better understanding of salt and baking soda functionality in the formation of soft flour dough, which will support the searching of feasible sodium reduction strategies in soft flour bakery products.

  7. Flexible robotic actuators

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

    Morin, Stephen A.; Shepherd, Robert F.; Stokes, Adam

    Systems and methods for providing flexible robotic actuators are disclosed. Some embodiments of the disclosed subject matter include a soft robot capable of providing a radial deflection motions; a soft tentacle actuator capable of providing a variety of motions and providing transportation means for various types of materials; and a hybrid robotic system that retains desirable characteristics of both soft robots and hard robots. Some embodiments of the disclosed subject matter also include methods for operating the disclosed robotic systems.

  8. Fiber-reinforced scaffolds in soft tissue engineering

    PubMed Central

    Wang, Wei; Fan, Yubo; Wang, Xiumei; Watari, Fumio

    2017-01-01

    Abstract Soft tissue engineering has been developed as a new strategy for repairing damaged or diseased soft tissues and organs to overcome the limitations of current therapies. Since most of soft tissues in the human body are usually supported by collagen fibers to form a three-dimensional microstructure, fiber-reinforced scaffolds have the advantage to mimic the structure, mechanical and biological environment of natural soft tissues, which benefits for their regeneration and remodeling. This article reviews and discusses the latest research advances on design and manufacture of novel fiber-reinforced scaffolds for soft tissue repair and how fiber addition affects their structural characteristics, mechanical strength and biological activities in vitro and in vivo. In general, the concept of fiber-reinforced scaffolds with adjustable microstructures, mechanical properties and degradation rates can provide an effective platform and promising method for developing satisfactory biomechanically functional implantations for soft tissue engineering or regenerative medicine. PMID:28798872

  9. Strategies to Improve Regeneration of the Soft Palate Muscles After Cleft Palate Repair

    PubMed Central

    Carvajal Monroy, Paola L.; Grefte, Sander; Kuijpers-Jagtman, Anne Marie; Wagener, Frank A.D.T.G.

    2012-01-01

    Children with a cleft in the soft palate have difficulties with speech, swallowing, and sucking. These patients are unable to separate the nasal from the oral cavity leading to air loss during speech. Although surgical repair ameliorates soft palate function by joining the clefted muscles of the soft palate, optimal function is often not achieved. The regeneration of muscles in the soft palate after surgery is hampered because of (1) their low intrinsic regenerative capacity, (2) the muscle properties related to clefting, and (3) the development of fibrosis. Adjuvant strategies based on tissue engineering may improve the outcome after surgery by approaching these specific issues. Therefore, this review will discuss myogenesis in the noncleft and cleft palate, the characteristics of soft palate muscles, and the process of muscle regeneration. Finally, novel therapeutic strategies based on tissue engineering to improve soft palate function after surgical repair are presented. PMID:22697475

  10. Strategies to improve regeneration of the soft palate muscles after cleft palate repair.

    PubMed

    Carvajal Monroy, Paola L; Grefte, Sander; Kuijpers-Jagtman, Anne Marie; Wagener, Frank A D T G; Von den Hoff, Johannes W

    2012-12-01

    Children with a cleft in the soft palate have difficulties with speech, swallowing, and sucking. These patients are unable to separate the nasal from the oral cavity leading to air loss during speech. Although surgical repair ameliorates soft palate function by joining the clefted muscles of the soft palate, optimal function is often not achieved. The regeneration of muscles in the soft palate after surgery is hampered because of (1) their low intrinsic regenerative capacity, (2) the muscle properties related to clefting, and (3) the development of fibrosis. Adjuvant strategies based on tissue engineering may improve the outcome after surgery by approaching these specific issues. Therefore, this review will discuss myogenesis in the noncleft and cleft palate, the characteristics of soft palate muscles, and the process of muscle regeneration. Finally, novel therapeutic strategies based on tissue engineering to improve soft palate function after surgical repair are presented.

  11. [Epidemiological characteristics and mortality risk factors in patients admitted in hospitals with soft tissue infections. A multicentric STIMG (Soft Tissue Infections Malacitan Group) study results].

    PubMed

    Salgado Ordóñez, F; Villar Jiménez, J; Hidalgo Conde, A; Villalobos Sánchez, A; de la Torre Lima, J; Aguilar García, J; da Rocha Costa, I; García Ordóñez, M A; Nuño Alvarez, E; Ramos Cantes, C; Martín Pérez, M

    2006-07-01

    To describe the characteristics of patients admitted in hospitals with soft tissue infections, and analyse the variables whose died, in order to define risk groups. retrospective analysis of medical reports of all patient admitted during 2002 year for soft tissue infections in public malacitans hospitals. We excluded the patient with soft tissue infections associated with burns, surgery, pressure ulcers, and orbit cellulitis. We analysed clinical, biochemical variables and indications for yields and imaging tests, so the empiric antibiotic treatment established and its correlations with practice guidelines. We analysed 391 admissions of 374 patients. Cellulitis was the most frequent diagnosis (69.3%). We did imaging tests in 51.6%. In 94.3% of cases were treated with empirics antibiotics. The most prescribed drug was amoxiciline plus clavulanate (39%). 27 patients died, 40.7% of them for septic cause. All deceased patients had chronic diseases. The only biochemical parameters associated with mortality were serum proteins and albumina (55 +/- 9 g/L vs. 63 +/- 8 g/L; p = 0.0231) and (22 +/- 7 g/L vs. 29 +/- 7 g/L; p = 0.0125) respectively. Cellullitis are the most frequent soft tissue infections that requires admissions in hospitals. We overuse imaging test and don t follow the practice guidelines recommendations in antibiotic therapy. Primary soft issue infection s mortality is low and it s restricted to people with chronic illness, deep infections and bad nutritional status.

  12. Modeling end-use quality in U. S. soft wheat germplasm

    USDA-ARS?s Scientific Manuscript database

    End-use quality in soft wheat (Triticum aestivum L.) can be assessed by a wide array of measurements, generally categorized into grain, milling, and baking characteristics. Samples were obtained from four regional nurseries. Selected parameters included: test weight, kernel hardness, kernel size, ke...

  13. Improved GSO Optimized ESN Soft-Sensor Model of Flotation Process Based on Multisource Heterogeneous Information Fusion

    PubMed Central

    Wang, Jie-sheng; Han, Shuang; Shen, Na-na

    2014-01-01

    For predicting the key technology indicators (concentrate grade and tailings recovery rate) of flotation process, an echo state network (ESN) based fusion soft-sensor model optimized by the improved glowworm swarm optimization (GSO) algorithm is proposed. Firstly, the color feature (saturation and brightness) and texture features (angular second moment, sum entropy, inertia moment, etc.) based on grey-level co-occurrence matrix (GLCM) are adopted to describe the visual characteristics of the flotation froth image. Then the kernel principal component analysis (KPCA) method is used to reduce the dimensionality of the high-dimensional input vector composed by the flotation froth image characteristics and process datum and extracts the nonlinear principal components in order to reduce the ESN dimension and network complex. The ESN soft-sensor model of flotation process is optimized by the GSO algorithm with congestion factor. Simulation results show that the model has better generalization and prediction accuracy to meet the online soft-sensor requirements of the real-time control in the flotation process. PMID:24982935

  14. Composite Materials for Maxillofacial Prostheses.

    DTIC Science & Technology

    1979-08-01

    block number) MAXILLOFACIAL PROSTHESES; PROSTHETIC MATERIALS; MICROCAPSULES ; SOFT FILLERS; ELASTuMER COMPOSITES 20,_ ABSTRACT ’Continue on reverse side...approaches were pursued toward making such microcapsules . One approach involves coaxial extrusion of a catalyzed elastomer precursor and core liquid into a...fabrication of maxillofacial prostheses. The projected composite systems are elastomeric-shelled, liquid-filled microcapsules . Two experimental approaches were

  15. Current knowledge of soft cheeses flavor and related compounds.

    PubMed

    Sablé, S; Cottenceau, G

    1999-12-01

    Cheese aroma is the result of the perception of a large number of molecules belonging to different chemical classes. The volatile compounds involved in the soft cheese flavor have received a great deal of attention. However, there has been less work concerning the volatile compounds in the soft smear-ripened cheeses than in the mold-ripened cheeses. This paper reviews the components that contribute to the characteristic flavor in the soft cheeses such as surface-ripened, Camembert-type, and Blue cheeses. The sensory properties and quantities of the molecules in the different cheeses are discussed.

  16. Non Lipomatous Benign Lesions Mimicking Soft-tissue Sarcomas: A Pictorial Essay.

    PubMed

    Coran, Alessandro; Orsatti, Giovanna; Crimì, Filippo; Rastrelli, Marco; DI Maggio, Antonio; Ponzoni, Alberto; Attar, Shady; Stramare, Roberto

    2018-01-01

    The incidental finding of soft tissue masses is a challenge for the radiologist. Benign and malignant lesions can be differentiated relying on patient history, symptoms and mostly with the help of imaging. Ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) become fundamental in order to distinguish these lesions but the radiologist needs to know the main characteristics of benign soft tissue masses and sarcomas. Herein, we present a pictorial review of lesions mimicking soft tissue sarcomas features. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  17. Importance of pH-regulated charge density on the electrophoresis of soft particles

    NASA Astrophysics Data System (ADS)

    Gopmandal, Partha P.; Ohshima, H.

    2017-02-01

    The present study deals with the electrophoresis of spherical soft particles consisting of an ion and liquid-penetrable but liquid-flow-impenetrable inner core surrounded by an ion and fluid-penetrable polyelectrolyte layer. The inner core is considered to be dielectric and bearing basic functional group coated with polyelectrolyte layer containing acidic functional group. An approximate expression for the electrophoretic mobility of such a particle is obtained under a low potential limit. The electrophoretic behaviour of the undertaken particle is investigated for a wide range of bulk pH values and electrolyte concentrations. Our study also indicates some remarkable features of the electrophoresis e.g., occurrence of zero mobility, mobility reversal etc.

  18. Soft sensor modelling by time difference, recursive partial least squares and adaptive model updating

    NASA Astrophysics Data System (ADS)

    Fu, Y.; Yang, W.; Xu, O.; Zhou, L.; Wang, J.

    2017-04-01

    To investigate time-variant and nonlinear characteristics in industrial processes, a soft sensor modelling method based on time difference, moving-window recursive partial least square (PLS) and adaptive model updating is proposed. In this method, time difference values of input and output variables are used as training samples to construct the model, which can reduce the effects of the nonlinear characteristic on modelling accuracy and retain the advantages of recursive PLS algorithm. To solve the high updating frequency of the model, a confidence value is introduced, which can be updated adaptively according to the results of the model performance assessment. Once the confidence value is updated, the model can be updated. The proposed method has been used to predict the 4-carboxy-benz-aldehyde (CBA) content in the purified terephthalic acid (PTA) oxidation reaction process. The results show that the proposed soft sensor modelling method can reduce computation effectively, improve prediction accuracy by making use of process information and reflect the process characteristics accurately.

  19. Influence of ultraviolet irradiation on data retention characteristics in resistive random access memory

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

    Kimura, K.; Ohmi, K.; Tottori University Electronic Display Research Center, 101 Minami4-chome, Koyama-cho, Tottori-shi, Tottori 680-8551

    With increasing density of memory devices, the issue of generating soft errors by cosmic rays is becoming more and more serious. Therefore, the irradiation resistance of resistance random access memory (ReRAM) to cosmic radiation has to be elucidated for practical use. In this paper, we investigated the data retention characteristics of ReRAM against ultraviolet irradiation with a Pt/NiO/ITO structure. Soft errors were confirmed to be caused by ultraviolet irradiation in both low- and high-resistance states. An analysis of the wavelength dependence of light irradiation on data retention characteristics suggested that electronic excitation from the valence to the conduction band andmore » to the energy level generated due to the introduction of oxygen vacancies caused the errors. Based on a statistically estimated soft error rates, the errors were suggested to be caused by the cohesion and dispersion of oxygen vacancies owing to the generation of electron-hole pairs and valence changes by the ultraviolet irradiation.« less

  20. Microscopic reversibility and memory in soft crystals undergoing large deformations

    NASA Astrophysics Data System (ADS)

    Rosenfeld, Liat; Stan, Claudiu; Tang, Sindy K. Y.

    2014-11-01

    In this study, we explore the transition from reversible to chaotic behavior in an oscillatory shear flow of water-in-oil emulsions. The emulsion was injected through a microchannel and was forced to rearrange due to a central constriction in the channel. We study the motion of the individual droplets and their neighbors in order to determine their ability to retain their original position after several cycles of oscillations. We have found that the emulsion exhibit behaviors that vary from complete reversibility to complete irreversibility depending on the volume fraction, velocity and strain rate. The reversibility, both in the trajectory and the deformation of every drop, is reproducible even when the drops undergo many rearrangement events over distances of >150 droplet diameters. Moreover, the deformability of the drops and the high volume fraction are crucial conditions for the onset of reversibility. We provide here the first direct visualization and physical analysis of this phenomenon. This work is an important step in describing the flow of concentrated emulsions and suspensions in microchannels and is therefore crucial for understanding the behavior of droplets, bubbles and particles in droplet microfluidic applications.

  1. Study of the magnetic interaction in nanocrystalline Pr-Fe-Co-Nb-B permanent magnets

    NASA Astrophysics Data System (ADS)

    Dospial, M.; Plusa, D.; Ślusarek, B.

    2012-03-01

    The magnetic properties of an isotropic, epoxy resin bonded magnets made from Pr-Fe-Co-Nb-B powder were investigated. The magnetization reversal process and magnetic parameters were examined by measurements of the initial magnetization curve, major and minor hysteresis loops and sets of recoil curves. From the initial magnetization curve and the field dependencies of the reversible and irreversible magnetization components derived from the recoil loops it was found that the magnetization reversal process is the combination of the nucleation of reversed domains and pinning of domain walls at the grain boundaries and the reversible rotation of magnetization vector in single domain grains. The interactions between grains were studied by means of δM plots. The nonlinear behavior of δM curve approve that the short range intergrain exchange coupling interactions are dominant in a field up to the sample coercivity. The interaction domains and fine magnetic structure were revealed as the evidence of exchange coupling between soft α-Fe and hard magnetic Nd2Fe14B grains.

  2. Performance characteristics of plane-wall venturi-like reverse flow diverters

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

    Smith, G.V.; Counce, R.M.

    1984-02-01

    The results of an analytical and experimental study of plane-wall venturi-like reverse flow diverters (RFD) are presented. In general, the flow characteristics of the RFD are reasonably well predicted by the mathematical model of the RFD, although a divergence between theory and data is observed for the output characteristics in the reverse flow mode as the output impedance is reduced. Overall, the performance of these devices indicates their usefulness in fluid control and fluid power systems, such as displacement pumping systems.

  3. Performance characteristics of plane-wall venturi-like reverse flow diverters

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

    Smith, G.V.; Counce, R.M.

    1982-01-01

    The results of an analytical and experimental study of plane-wall venturi-like reverse flow diverters (RFD) are presented. In general, the flow characteristics of the RFD are reasonably well predicted by the mathematical model of the RFD, although a divergence between theory and data is observed for the output characteristics in the reverse flow mode as the output impedance is reduced. Overall, the performance of these devices indicates their usefulness in fluid control and fluid power systems, such as displacement pumping systems.

  4. Differentiating between Women in Hard and Soft Science and Engineering Disciplines

    ERIC Educational Resources Information Center

    Camp, Amanda G.; Gilleland, Diane S.; Pearson, Carolyn; Vander Putten, James

    2010-01-01

    The intent of this study was to investigate characteristics that differentiate between women in soft (social, psychological, and life sciences) and hard (engineering, mathematics, computer science, physical science) science and engineering disciplines. Using the Beginning Postsecondary Students Longitudinal Study: 1996-2001 (2002), a descriptive…

  5. Recent Empirical Studies of the Pedagogical Effects of Interactive Video Instruction in "Soft Skill" Areas.

    ERIC Educational Resources Information Center

    Cronin, Michael W.; Cronin, Karen A.

    1992-01-01

    Recent empirical research has identified significant advantages for interactive video instruction over traditional teaching methods in "soft skill" (humanities and social sciences) areas, including cognitive achievement, transfer of learning to performance, learning motivation, student achievement across uncontrolled student characteristics, user…

  6. Identification of milling and baking quality QTL in multiple soft wheat mapping populations

    USDA-ARS?s Scientific Manuscript database

    Wheat derived food products require a range of characteristics. Identification and understanding of the genetic components controlling end-use quality of wheat is important for crop improvement. We assessed the underlying genetics controlling specific milling and baking quality parameters of soft wh...

  7. Soft x-ray scattering facility at the Advanced Light Source with real-time data processing and analysis

    NASA Astrophysics Data System (ADS)

    Gann, E.; Young, A. T.; Collins, B. A.; Yan, H.; Nasiatka, J.; Padmore, H. A.; Ade, H.; Hexemer, A.; Wang, C.

    2012-04-01

    We present the development and characterization of a dedicated resonant soft x-ray scattering facility. Capable of operation over a wide energy range, the beamline and endstation are primarily used for scattering from soft matter systems around the carbon K-edge (˜285 eV). We describe the specialized design of the instrument and characteristics of the beamline. Operational characteristics of immediate interest to users such as polarization control, degree of higher harmonic spectral contamination, and detector noise are delineated. Of special interest is the development of a higher harmonic rejection system that improves the spectral purity of the x-ray beam. Special software and a user-friendly interface have been implemented to allow real-time data processing and preliminary data analysis simultaneous with data acquisition.

  8. Four-dimensional Printing of Liquid Crystal Elastomers.

    PubMed

    Ambulo, Cedric P; Burroughs, Julia J; Boothby, Jennifer M; Kim, Hyun; Shankar, M Ravi; Ware, Taylor H

    2017-10-25

    Three-dimensional structures capable of reversible changes in shape, i.e., four-dimensional-printed structures, may enable new generations of soft robotics, implantable medical devices, and consumer products. Here, thermally responsive liquid crystal elastomers (LCEs) are direct-write printed into 3D structures with a controlled molecular order. Molecular order is locally programmed by controlling the print path used to build the 3D object, and this order controls the stimulus response. Each aligned LCE filament undergoes 40% reversible contraction along the print direction on heating. By printing objects with controlled geometry and stimulus response, magnified shape transformations, for example, volumetric contractions or rapid, repetitive snap-through transitions, are realized.

  9. Dynamic and rheological properties of soft biological cell suspensions

    PubMed Central

    Yazdani, Alireza; Li, Xuejin

    2016-01-01

    Quantifying dynamic and rheological properties of suspensions of soft biological particles such as vesicles, capsules, and red blood cells (RBCs) is fundamentally important in computational biology and biomedical engineering. In this review, recent studies on dynamic and rheological behavior of soft biological cell suspensions by computer simulations are presented, considering both unbounded and confined shear flow. Furthermore, the hemodynamic and hemorheological characteristics of RBCs in diseases such as malaria and sickle cell anemia are highlighted. PMID:27540271

  10. Photoreversible Covalent Hydrogels for Soft-Matter Additive Manufacturing.

    PubMed

    Kabb, Christopher P; O'Bryan, Christopher S; Deng, Christopher C; Angelini, Thomas E; Sumerlin, Brent S

    2018-05-16

    Reversible covalent chemistry provides access to robust materials with the ability to be degraded and reformed upon exposure to an appropriate stimulus. Photoresponsive units are attractive for this purpose, as the spatial and temporal application of light is easily controlled. Coumarin derivatives undergo a [2 + 2] cycloaddition upon exposure to long-wave UV irradiation (365 nm), and this process can be reversed using short-wave UV light (254 nm). Therefore, polymers cross-linked by coumarin groups are excellent candidates as reversible covalent gels. In this work, copolymerization of coumarin-containing monomers with the hydrophilic comonomer N, N-dimethylacrylamide yielded water-soluble, linear polymers that could be cured with long-wave UV light into free-standing hydrogels, even in the absence of a photoinitiator. Importantly, the gels were reverted back to soluble copolymers upon short-wave UV irradiation. This process could be cycled, allowing for recycling and remolding of the hydrogel into additional shapes. Further, this hydrogel can be imprinted with patterns through a mask-based, post-gelation photoetching method. Traditional limitations of this technique, such as the requirement for uniform etching in one direction, have been overcome by combining these materials with a soft-matter additive manufacturing methodology. In a representative application of this approach, we printed solid structures in which the interior coumarin-cross-linked gel is surrounded by a nondegradable gel. Upon exposure to short-wave UV irradiation, the coumarin-cross-linked gel was reverted to soluble prepolymers that were washed away to yield hollow hydrogel objects.

  11. Functional buckling behavior of silicone rubber shells for biomedical use.

    PubMed

    van der Houwen, E B; Kuiper, L H; Burgerhof, J G M; van der Laan, B F A M; Verkerke, G J

    2013-12-01

    The use of soft elastic biomaterials in medical devices enables substantial function integration. The consequent increased simplification in design can improve reliability at a lower cost in comparison to traditional (hard) biomaterials. Functional bi-stable buckling is one of the many new mechanisms made possible by soft materials. The buckling behavior of shells, however, is typically described from a structural failure point of view: the collapse of arches or rupture of steam vessels, for example. There is little or no literature about the functional elastic buckling of small-sized silicone rubber shells, and it is unknown whether or not theory can predict their behavior. Is functional buckling possible within the scale, material and pressure normally associated with physiological applications? An automatic speech valve is used as an example application. Silicone rubber spherical shells (diameter 30mm) with hinged and double-hinged boundaries were subjected to air pressure loading. Twelve different geometrical configurations were tested for buckling and reverse buckling pressures. Data were compared with the theory. Buckling pressure increases linearly with shell thickness and shell height. Reverse buckling shows these same relations, with pressures always below normal buckling pressure. Secondary hinges change normal/reverse buckling pressure ratios and promote symmetrical buckling. All tested configurations buckled within or closely around physiological pressures. Functional bi-stable buckling of silicone rubber shells is possible with adjustable properties in the physiological pressure range. Results can be predicted using the proposed relations and equations. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Lack of detection of a putative retrovirus associated with haemic neoplasia in the soft shell clam Mya arenaria.

    PubMed

    AboElkhair, M; Iwamoto, T; Clark, K F; McKenna, P; Siah, A; Greenwood, S J; Berthe, F C J; Casey, J W; Cepica, A

    2012-01-01

    Haemic neoplasia (HN) is a leukemia-like disease that affects at least 20 species of marine bivalves including soft shell clam, Mya arenaria. Since the disease was discovered in 1969, the etiology remains unknown. A retroviral etiology has been suggested based on the detection of reverse transcriptase activity and electron microscopic observation of retroviral-like particles using negative staining. To date, however no virus isolate and no retroviral sequence from HN has been obtained. Moreover, transmission of the disease by cell-free filtrate from affected clams has not been reproduced. In the current study, we reinvestigated the association of HN with a putative retrovirus. Sucrose gradient centrifugation followed by assessment of reverse transcriptase activity, electrophoretic analysis of protein and RNA, and electron microscopic examinations of fractions corresponding to retroviral density were employed. Detection of retroviral pol sequences using degenerate RT-PCR approaches was also attempted. Our results showed visible bands at the expected density of retrovirus in HN-positive and HN-negative clam tissues and both with reverse transcriptase activity. Electron microscopy, RNA analysis, protein analysis, and PCR systems targeting the pol gene of retroviruses did not however provide clear evidence supporting presence of a retrovirus. We point out that the retrovirus etiology of HN of Mya arenaria proposed some 25 years ago should be reconsidered in the absence of a virus isolate or virus sequences. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Energy efficient and fast reversal of a fixed skyrmion two-terminal memory with spin current assisted by voltage controlled magnetic anisotropy

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Dhritiman; Mamun Al-Rashid, Md; Atulasimha, Jayasimha

    2017-10-01

    Recent work (P-H Jang et al 2015 Appl. Phys. Lett. 107 202401, J. Sampaio et al 2016 Appl. Phys. Lett. 108 112403) suggests that ferromagnetic reversal with spin transfer torque (STT) requires more current in a system in the presence of Dzyaloshinskii-Moriya interaction (DMI) than switching a typical ferromagnet of the same dimensions and perpendicular magnetic anisotropy (PMA). However, DMI promotes the stabilization of skyrmions and we report that when perpendicular anisotropy is modulated (reduced) for both the skyrmion and ferromagnet, it takes a much smaller current to reverse the fixed skyrmion than to reverse the ferromagnet in the same amount of time, or the skyrmion reverses much faster than the ferromagnet at similar levels of current. We show with rigorous micromagnetic simulations that skyrmion switching proceeds along a different path at very low PMA, which results in a significant reduction in the spin current or time required for reversal. This can offer potential for memory applications where a relatively simple modification of the standard STT-RAM (to include a heavy metal adjacent to the soft magnetic layer and with appropriate design of the tunnel barrier) can lead to an energy efficient and fast magnetic memory device based on the reversal of fixed skyrmions.

  14. Histomorphometrical analysis following augmentation of infected extraction sites exhibiting severe bone loss and primarily closed by intrasocket reactive soft tissue.

    PubMed

    Mardinger, Ofer; Vered, Marilena; Chaushu, Gavriel; Nissan, Joseph

    2012-06-01

    Intrasocket reactive soft tissue can be used for primary closure during augmentation of infected extraction sites exhibiting severe bone loss prior to implant placement. The present study evaluated the histological characteristics of the initially used intrasocket reactive soft tissue, the overlying soft tissue, and the histomorphometry of the newly formed bone during implant placement. Thirty-six consecutive patients (43 sites) were included in the study. Extraction sites demonstrating extensive bone loss on preoperative periapical and panoramic radiographs served as inclusion criteria. Forty-three implants were inserted after a healing period of 6 months. Porous bovine xenograft bone mineral was used as a single bone substitute. The intrasocket reactive soft tissue was sutured over the grafting material to seal the coronal portion of the socket. Biopsies of the intrasocket reactive soft tissue at augmentation, healed mucosa, and bone cores at implant placement were retrieved and evaluated. The intrasocket reactive soft tissue demonstrated features compatible with granulation tissue and long junctional epithelium. The mucosal samples at implant placement demonstrated histopathological characteristics of keratinized mucosa with no residual elements of granulation tissue. Histomorphometrically, the mean composition of the bone cores was - vital bone 40 ± 19% (13.7-74.8%); bone substitute 25.7 ± 13% (0.6-51%); connective tissue 34.3 ± 15% (13.8-71.9%). Intrasocket reactive soft tissue used for primary closure following ridge augmentation is composed of granulation tissue and long junctional epithelium. At implant placement, clinical and histological results demonstrate its replacement by keratinized gingiva. The histomorphometrical results reveal considerable bone formation. Fresh extraction sites of hopeless teeth demonstrating chronic infection and severe bone loss may be grafted simultaneously with their removal. © 2010 Wiley Periodicals, Inc.

  15. Illusory sense of human touch from a warm and soft artificial hand.

    PubMed

    Cabibihan, John-John; Joshi, Deepak; Srinivasa, Yeshwin Mysore; Chan, Mark Aaron; Muruganantham, Arrchana

    2015-05-01

    To touch and be touched are vital to human development, well-being, and relationships. However, to those who have lost their arms and hands due to accident or war, touching becomes a serious concern that often leads to psychosocial issues and social stigma. In this paper, we demonstrate that the touch from a warm and soft rubber hand can be perceived by another person as if the touch were coming from a human hand. We describe a three-step process toward this goal. First, we made participants select artificial skin samples according to their preferred warmth and softness characteristics. At room temperature, the preferred warmth was found to be 28.4 °C at the skin surface of a soft silicone rubber material that has a Shore durometer value of 30 at the OO scale. Second, we developed a process to create a rubber hand replica of a human hand. To compare the skin softness of a human hand and artificial hands, a robotic indenter was employed to produce a softness map by recording the displacement data when constant indentation force of 1 N was applied to 780 data points on the palmar side of the hand. Results showed that an artificial hand with skeletal structure is as soft as a human hand. Lastly, the participants' arms were touched with human and artificial hands, but they were prevented from seeing the hand that touched them. Receiver operating characteristic curve analysis suggests that a warm and soft artificial hand can create an illusion that the touch is from a human hand. These findings open the possibilities for prosthetic and robotic hands that are life-like and are more socially acceptable.

  16. The detection of soft X-rays with charged coupled detectors

    NASA Technical Reports Server (NTRS)

    Burstein, P.; Davis, John M.

    1989-01-01

    The characteristics of an ideal soft X-ray imaging detector are enumerated. Of recent technical developments the CCD or charge coupled device goes furthest to meeting these requirements. Several properties of CCDs are described with reference to experimental work and their application to practical instruments is reviewed.

  17. Paleointensity Behavior and Intervals Between Geomagnetic Reversals in the Last 167 Ma

    NASA Astrophysics Data System (ADS)

    Kurazhkovskii, A. Yu.; Kurazhkovskaya, N. A.; Klain, B. I.

    2018-01-01

    The results of comparative analysis of the behavior of paleointensity and polarity (intervals between reversals) of the geomagnetic field for the last 167 Ma are presented. Similarities and differences in the behavior of these characteristics of the geomagnetic field are discussed. It is shown that bursts of paleointensity and long intervals between reversals occurred at high mean values of paleointensity in the Cretaceous and Paleogene. However, there are differences between the paleointensity behavior and the reversal regime: (1) the characteristic times of paleointensity variations are less than the characteristic times of the frequency of geomagnetic reversals, (2) the achievement of maximum values of paleointensity at the Cretaceous-Paleogene boundary and the termination of paleointensity bursts after the boundary of 45-40 Ma are not marked by explicit features in the geomagnetic polarity behavior.

  18. Unstable behaviour of RPT when testing turbine characteristics in the laboratory

    NASA Astrophysics Data System (ADS)

    Nielsen, T. K.; Fjørtoft Svarstad, M.

    2014-03-01

    A reversible pump turbine is a machine that can operate in three modes of operation i.e. in pumping mode. in turbine mode and in phase compensating mode (idle speed). Reversible pump turbines have an increasing importance for regulation purposes for obtaining power balance in electric power systems. Especially in grids dominated by thermal energy. reversible pump turbines improve the overall power regulating ability. Increased use of renewables (wind-. wave- and tidal power plants) will utterly demand better regulation ability of the traditional water power systems. enhancing the use of reversible pump turbines. A reversible pump turbine is known for having incredible steep speed - flow characteristics. As the speed increases the flow decreases more than that of a Francis turbines with the same specific speed. The steep characteristics might cause severe stability problems in turbine mode of operation. Stability in idle speed is a necessity for phasing in the generator to the electric grid. In the design process of a power plant. system dynamic simulations must be performed in order to check the system stability. The turbine characteristics will have to be modelled with certain accuracy even before one knows the exact turbine design and have measured characteristics. A representation of the RPT characteristics for system dynamic simulation purposes is suggested and compared with measured characteristics. The model shows good agreement with RPT characteristics measured in The Waterpower Laboratory. Because of the S-shaped characteristics. there is a stability issue involved when measuring these characteristics. Without special measures. it is impossible to achieve stable conditions in certain operational points. The paper discusses the mechanism when using a throttle to achieve system stability. even if the turbine characteristics imply instability.

  19. The results of a low-speed wind tunnel test to investigate the effects of the Refan JT8D engine target thrust reverser on the stability and control characteristics of the Boeing 727-200 airplane

    NASA Technical Reports Server (NTRS)

    Kupcis, E. A.

    1974-01-01

    The effects of the Refan JT8D side engine target thrust reverser on the stability and control characteristics of the Boeing 727-200 airplane were investigated using the Boeing-Vertol 20 x 20 ft Low-Speed Wind Tunnel. A powered model of the 727-200 was tested in groud effect in the landing configuration. The Refan target reverser configuration was evaluated relative to the basic production 727 airplane with its clamshell-deflector door thrust reverser design. The Refan configuration had slightly improved directional control characteristics relative to the basic airplane. Clocking the Refan thrust reversers 20 degrees outboard to direct the reverser flow away from the vertical tail, had little effect on directional control. However, clocking them 20 degrees inboard resulted in a complete loss of rudder effectiveness for speeds greater than 90 knots. Variations in Refan reverser lip/fence geometry had a minor effect on directional control.

  20. Jammed elastic shells - a 3D experimental soft frictionless granular system

    NASA Astrophysics Data System (ADS)

    Jose, Jissy; Blab, Gerhard A.; van Blaaderen, Alfons; Imhof, Arnout

    2015-03-01

    We present a new experimental system of monodisperse, soft, frictionless, fluorescent labelled elastic shells for the characterization of structure, universal scaling laws and force networks in 3D jammed matter. The interesting fact about these elastic shells is that they can reversibly deform and therefore serve as sensors of local stress in jammed matter. Similar to other soft particles, like emulsion droplets and bubbles in foam, the shells can be packed to volume fractions close to unity, which allows us to characterize the contact force distribution and universal scaling laws as a function of volume fraction, and to compare them with theoretical predictions and numerical simulations. However, our shells, unlike other soft particles, deform rather differently at large stresses. They deform without conserving their inner volume, by forming dimples at contact regions. At each contact one of the shells buckled with a dimple and the other remained spherical, closely resembling overlapping spheres. We conducted 3D quantitative analysis using confocal microscopy and image analysis routines specially developed for these particles. In addition, we analysed the randomness of the process of dimpling, which was found to be volume fraction dependent.

  1. Polybenzoxazole Nanofiber-Reinforced Moisture-Responsive Soft Actuators.

    PubMed

    Chen, Meiling; Frueh, Johannes; Wang, Daolin; Lin, Xiankun; Xie, Hui; He, Qiang

    2017-04-10

    Hydromorphic biological systems, such as morning glory flowers, pinecones, and awns, have inspired researchers to design moisture-sensitive soft actuators capable of directly converting the change of moisture into motion or mechanical work. Here, we report a moisture-sensitive poly(p-phenylene benzobisoxazole) nanofiber (PBONF)-reinforced carbon nanotube/poly(vinyl alcohol) (CNT/PVA) bilayer soft actuator with fine performance on conductivity and mechanical properties. The embedded PBONFs not only assist CNTs to form a continuous, conductive film, but also enhance the mechanical performance of the actuators. The PBONF-reinforced CNT/PVA bilayer actuators can unsymmetrically adsorb and desorb water, resulting in a reversible deformation. More importantly, the actuators show a pronounced increase of conductivity due to the deformation induced by the moisture change, which allows the integration of a moisture-sensitive actuator and a humidity sensor. Upon changing the environmental humidity, the actuators can respond by the deformation for shielding and report the humidity change in a visual manner, which has been demonstrated by a tweezer and a curtain. Such nanofiber-reinforced bilayer actuators with the sensing capability should hold considerable promise for the applications such as soft robots, sensors, intelligent switches, integrated devices, and material storage.

  2. Carbonated soft drinks induce oxidative stress and alter the expression of certain genes in the brains of Wistar rats.

    PubMed

    El-Terras, Adel; Soliman, Mohamed Mohamed; Alkhedaide, Adel; Attia, Hossam Fouad; Alharthy, Abdullah; Banaja, Abdel Elah

    2016-04-01

    In Saudi Arabia, the consumption of carbonated soft drinks is common and often occurs with each meal. Carbonated soft drink consumption has been shown to exhibit effects on the liver, kidney and bone. However, the effects of these soft drinks on brain activity have not been widely examined, particularly at the gene level. Therefore, the current study was conducted with the aim of evaluating the effects of chronic carbonated soft drink consumption on oxidative stress, brain gene biomarkers associated with aggression and brain histology. In total, 40 male Wistar rats were divided into four groups: Group 1 served as a control and was provided access to food and water ad libitum; and groups 2‑4 were given free access to food and carbonated soft drinks only (Cola for group 2, Pepsi for group 3 and 7‑UP for group 4). Animals were maintained on these diets for 3 consecutive months. Upon completion of the experimental period, animals were sacrificed and serological and histopathological analyses were performed on blood and tissues samples. Reverse transcription‑polymerase chain reaction was used to analyze alterations in gene expression levels. Results revealed that carbonated soft drinks increased the serum levels of malondialdehyde (MDA). Carbonated soft drinks were also observed to downregulate the expression of antioxidants glutathione reductase (GR), catalase and glutathione peroxidase (GPx) in the brain when compared with that in the control rats. Rats administered carbonated soft drinks also exhibited decreased monoamine oxidase A (MAO‑A) and acetylcholine esterase (AChE) serum and mRNA levels in the brain. In addition, soft drink consumption upregulated mRNA expression of dopamine D2 receptor (DD2R), while 5-hydroxytryptamine transporter (5‑HTT) expression was decreased. However, following histological examination, all rats had a normal brain structure. The results of this study demonstrated that that carbonated soft drinks induced oxidative stress and altered the expression of certain genes that are associated with the brain activity and thus should be consumed with caution.

  3. Photo-triggered solvent-free metamorphosis of polymeric materials.

    PubMed

    Honda, Satoshi; Toyota, Taro

    2017-09-11

    Liquefaction and solidification of materials are the most fundamental changes observed during thermal phase transitions, yet the design of organic and polymeric soft materials showing isothermal reversible liquid-nonliquid conversion remains challenging. Here, we demonstrate that solvent-free repeatable molecular architectural transformation between liquid-star and nonliquid-network polymers that relies on cleavage and reformation of a covalent bond in hexaarylbiimidazole. Liquid four-armed star-shaped poly(n-butyl acrylate) and poly(dimethyl siloxane) with 2,4,5-triphenylimidazole end groups were first synthesized. Subsequent oxidation of the 2,4,5-triphenylimidazoles into 2,4,5-triphenylimidazoryl radicals and their coupling with these liquid star polymers to form hexaarylbiimidazoles afforded the corresponding nonliquid network polymers. The resulting nonliquid network polymers liquefied upon UV irradiation and produced liquid star-shaped polymers with 2,4,5-triphenylimidazoryl radical end groups that reverted to nonliquid network polymers again by recoupling of the generated 2,4,5-triphenylimidazoryl radicals immediately after terminating UV irradiation.The design of organic and polymeric soft materials showing isothermal reversible liquid-nonliquid conversion is challenging. Here, the authors show solvent-free repeatable molecular architectural transformation between liquid-star and non-liquid-network polymers by the cleavage and reformation of covalent bonds in the polymer chain.

  4. Energy dependence of the band-limited noise in black hole X-ray binaries★

    NASA Astrophysics Data System (ADS)

    Stiele, H.; Yu, W.

    2015-10-01

    Black hole low-mass X-ray binaries show a variety of variability features, which manifest as narrow peak-like structures superposed on broad noise components in power density spectra in the hard X-ray emission. In this work, we study variability properties of the band-limited noise component during the low-hard state for a sample of black hole X-ray binaries. We investigate the characteristic frequency and amplitude of the band-limited noise component and study covariance spectra. For observations that show a noise component with a characteristic frequency above 1 Hz in the hard energy band (4-8 keV), we found this very same component at a lower frequency in the soft band (1-2 keV). This difference in characteristic frequency is an indication that while both the soft and the hard band photons contribute to the same band-limited noise component, which likely represents the modulation of the mass accretion rate, the origin of the soft photons is actually further away from the black hole than the hard photons. Thus, the soft photons are characterized by larger radii, lower frequencies and softer energies, and are probably associated with a smaller optical depth for Comptonization up-scattering from the outer layer of the corona, or suggest a temperature gradient of the corona. We interpret this energy dependence within the picture of energy-dependent power density states as a hint that the contribution of the up-scattered photons originating in the outskirts of the Comptonizing corona to the overall emission in the soft band is becoming significant.

  5. Casimir stress in materials: Hard divergency at soft walls

    NASA Astrophysics Data System (ADS)

    Griniasty, Itay; Leonhardt, Ulf

    2017-11-01

    The Casimir force between macroscopic bodies is well understood, but not the Casimir stress inside bodies. Suppose empty space or a uniform medium meets a soft wall where the refractive index is continuous but its derivative jumps. For this situation we predict a characteristic power law for the stress inside the soft wall and close to its edges. Our result shows that such edges are not tolerated in the aggregation of liquids at surfaces, regardless whether the liquid is attracted or repelled.

  6. Design and Fabrication of a Universal Soft Gripper

    NASA Astrophysics Data System (ADS)

    Sabzehzar, Amin

    Inspired from nature, soft robots capable of actively tuning their mechanical rigidity can rapidly transition between a broad range of motor tasks, from lifting heavy loads to dexterous manipulation of delicate objects. Reversible rigidity tuning also enables soft robotic actuators to reroute their internal loading and alter their mode of deformation in response to intrinsic activation. In this study, we demonstrate this principle with a three-fingered pneumatic gripper that contains programmable ligaments that change stiness when activated with electrical current. The ligaments are composed of a conductive thermoplastic elastomer composite that reversibly softens under resistive heating. Depending on which ligaments are activated, the gripper will bend inward to pick up an object, bend laterally to twist it, or bend outward to release it. Each finger consists of three PDMS phalanges that are attached with two Ecoflex joints. Three ligaments (strips of a cPBE-PDMS composite layer) are attached along the finger and are stimulated with electricity individually. When the high pressure air is injected in the hollow middle part of the finger, the finger will be bent in the opposite direction of the stimulated cPBE-PDMS element (softer wall). This enables the gripper's fingers to grab and twist objects with dierent sizes and shapes. All of the gripper motions are generated with a single pneumatic source of pressure and are controlled with an electrical board. The ability to incorporate electrically programmable ligaments in pneumatic or hydraulic actuators has the potential to enhance versatility and reduce dependency on tubing and valves. In this study, an activation/deactivation cycle can be completed within 15 s.

  7. X-Rays from the Explosion Site: Fifteen Years of Light Curves of SN 1993J

    NASA Technical Reports Server (NTRS)

    Chandra, Poonam; Dwarkadas, Vikram V.; Ray, Alak; Immler, Stefan; Pooley, David

    2009-01-01

    We present a comprehensive analysis of the X-ray light curves of SN 1993J in a nearby galaxy M81. This is the only supernova other than SN 1987A, which is so extensively followed in the X-ray bands. Here we report on SN 1993J observations with the Chandra in the year 2005 and 2008, and Swift observations in 2005, 2006 and 2008. We combined these observations with all available archival data of SN 1993J, which includes ROSAT, ASCA, Chandra, and XMM-Newton, observations from 1993 April to 2006 August. In this paper we report the X-ray light curves of SN 1993J, extending up to fifteen years, in the soft (0.3-2.4 keV), hard (2-8 keV) and combined (0.3-8 keV) bands. The hard and soft-band fluxes decline at different rates initially, but after about 5 years they both undergo a t(sup -1) decline. The soft X-rays, which are initially low, start dominating after a few hundred days. We interpret that most of the emission below 8 keV is coming from the reverse shock which is radiative initially for around first 1000-2000 days and then turn into adiabatic shock. Our hydrodynamic simulation also confirms the reverse shock origin of the observed light curves. We also compare the Ha line luminosity of SN 1993J with its X-ray light curve and note that the Ha line luminosity has a fairly high fraction of the X-ray emission, indicating presence of clumps in the emitting plasma.

  8. Soft Expansion of Double-Real-Virtual Corrections to Higgs Production at N$^3$LO

    DOE PAGES

    Anastasiou, Charalampos; Duhr, Claude; Dulat, Falko; ...

    2015-05-15

    We present methods to compute higher orders in the threshold expansion for the one-loop production of a Higgs boson in association with two partons at hadron colliders. This process contributes to the N 3LO Higgs production cross section beyond the soft-virtual approximation. We use reverse unitarity to expand the phase-space integrals in the small kinematic parameters and to reduce the coefficients of the expansion to a small set of master integrals. We describe two methods for the calculation of the master integrals. The first was introduced for the calculation of the soft triple-real radiation relevant to N 3LO Higgs production.more » The second uses a particular factorization of the three body phase-space measure and the knowledge of the scaling properties of the integral itself. Our result is presented as a Laurent expansion in the dimensional regulator, although some of the master integrals are computed to all orders in this parameter.« less

  9. Buckligami: Actuation of soft structures through mechanical instabilities

    NASA Astrophysics Data System (ADS)

    Lazarus, Arnaud; Reis, Pedro

    2013-03-01

    We present a novel mechanism for actuating soft structures, that is triggered through buckling. Our elastomeric samples are rapid-prototyped using digital fabrication and comprise of a cylindrical shell patterned with an array of voids, each of which is covered by a thin membrane. Decreasing the internal pressure of the structure induces local buckling of the ligaments of the pattern, resulting in controllable folding of the global structure. Using rigid inclusions to plug the voids in specific geometric arrangements allows us to excite a variety of different fundamental motions of the cylindrical shell, including flexure and twist. We refer to this new mechanism of buckling-induced folding as ``buckligami.'' Given that geometry, elasticity and buckling are the underlying ingredients of this local folding mechanism, the global actuation is scalable, reversible and repeatable. Characterization and rationalization of our experiments provide crucial fundamental understanding to aid the design of new scale-independent actuators, with potential implications in the field of soft robotics.

  10. A Survey and Proposed Framework on the Soft Biometrics Technique for Human Identification in Intelligent Video Surveillance System

    PubMed Central

    Kim, Min-Gu; Moon, Hae-Min; Chung, Yongwha; Pan, Sung Bum

    2012-01-01

    Biometrics verification can be efficiently used for intrusion detection and intruder identification in video surveillance systems. Biometrics techniques can be largely divided into traditional and the so-called soft biometrics. Whereas traditional biometrics deals with physical characteristics such as face features, eye iris, and fingerprints, soft biometrics is concerned with such information as gender, national origin, and height. Traditional biometrics is versatile and highly accurate. But it is very difficult to get traditional biometric data from a distance and without personal cooperation. Soft biometrics, although featuring less accuracy, can be used much more freely though. Recently, many researchers have been made on human identification using soft biometrics data collected from a distance. In this paper, we use both traditional and soft biometrics for human identification and propose a framework for solving such problems as lighting, occlusion, and shadowing. PMID:22919273

  11. A survey and proposed framework on the soft biometrics technique for human identification in intelligent video surveillance system.

    PubMed

    Kim, Min-Gu; Moon, Hae-Min; Chung, Yongwha; Pan, Sung Bum

    2012-01-01

    Biometrics verification can be efficiently used for intrusion detection and intruder identification in video surveillance systems. Biometrics techniques can be largely divided into traditional and the so-called soft biometrics. Whereas traditional biometrics deals with physical characteristics such as face features, eye iris, and fingerprints, soft biometrics is concerned with such information as gender, national origin, and height. Traditional biometrics is versatile and highly accurate. But it is very difficult to get traditional biometric data from a distance and without personal cooperation. Soft biometrics, although featuring less accuracy, can be used much more freely though. Recently, many researchers have been made on human identification using soft biometrics data collected from a distance. In this paper, we use both traditional and soft biometrics for human identification and propose a framework for solving such problems as lighting, occlusion, and shadowing.

  12. Erratum: Correction to: Long- and Mid-Term Variations of the Soft X-ray Flare Character in Solar Cycles

    NASA Astrophysics Data System (ADS)

    Chertok, I. M.; Belov, A. V.

    2018-03-01

    Correction to: Solar Phys https://doi.org/10.1007/s11207-017-1169-1 We found an important error in the text of our article. On page 6, the second sentence of Section 3.2 "We studied the variations in soft X-ray flare characteristics in more detail by averaging them within the running windows of ± one Carrington rotation with a step of two rotations." should instead read "We studied the variations in soft X-ray flare characteristics in more detail by averaging them within the running windows of ± 2.5 Carrington rotations with a step of two rotations." We regret the inconvenience. The online version of the original article can be found at https://doi.org/10.1007/s11207-017-1169-1

  13. Soft x-ray scattering facility at the Advanced Light Source with real-time data processing and analysis.

    PubMed

    Gann, E; Young, A T; Collins, B A; Yan, H; Nasiatka, J; Padmore, H A; Ade, H; Hexemer, A; Wang, C

    2012-04-01

    We present the development and characterization of a dedicated resonant soft x-ray scattering facility. Capable of operation over a wide energy range, the beamline and endstation are primarily used for scattering from soft matter systems around the carbon K-edge (∼285 eV). We describe the specialized design of the instrument and characteristics of the beamline. Operational characteristics of immediate interest to users such as polarization control, degree of higher harmonic spectral contamination, and detector noise are delineated. Of special interest is the development of a higher harmonic rejection system that improves the spectral purity of the x-ray beam. Special software and a user-friendly interface have been implemented to allow real-time data processing and preliminary data analysis simultaneous with data acquisition. © 2012 American Institute of Physics

  14. A versatile model for soft patchy particles with various patch arrangements.

    PubMed

    Li, Zhan-Wei; Zhu, You-Liang; Lu, Zhong-Yuan; Sun, Zhao-Yan

    2016-01-21

    We propose a simple and general mesoscale soft patchy particle model, which can felicitously describe the deformable and surface-anisotropic characteristics of soft patchy particles. This model can be used in dynamics simulations to investigate the aggregation behavior and mechanism of various types of soft patchy particles with tunable number, size, direction, and geometrical arrangement of the patches. To improve the computational efficiency of this mesoscale model in dynamics simulations, we give the simulation algorithm that fits the compute unified device architecture (CUDA) framework of NVIDIA graphics processing units (GPUs). The validation of the model and the performance of the simulations using GPUs are demonstrated by simulating several benchmark systems of soft patchy particles with 1 to 4 patches in a regular geometrical arrangement. Because of its simplicity and computational efficiency, the soft patchy particle model will provide a powerful tool to investigate the aggregation behavior of soft patchy particles, such as patchy micelles, patchy microgels, and patchy dendrimers, over larger spatial and temporal scales.

  15. Reverse bias voltage testing of 8 cm x 8cm silicon solar cells

    NASA Technical Reports Server (NTRS)

    Woike, T.; Stotlar, S.; Lungu, C.

    1991-01-01

    A study is described of the reverse I-V characteristics of the largest space qualified silicon solar cells currently available (8 x 8 cm) and of reverse bias voltage (RBV) testing performed on these cells. This study includes production grade cells, both with and without cover glass. These cells span the typical output range seen in production. Initial characteristics of these cells are measured at both 28 and 60 C. These measurements show weak correlation between cell output and reverse characteristics. Analysis is presented to determine the proper conditions for RBV stress to simulate shadowing effects on a particular array design. After performing the RBV stress the characteristics of the stressed cells are remeasured. The degradation in cell performance is highly variable which exacerbates cell mismatching over time. The effect of this degradation on array lifetime is also discussed. Generalization of these results to other array configurations is also presented.

  16. Estimation of the viscous properties of skin and subcutaneous tissue in uniaxial stress relaxation tests.

    PubMed

    Wu, John Z; Cutlip, Robert G; Welcome, Daniel; Dong, Ren G

    2006-01-01

    Knowledge of viscoelastic properties of soft tissues is essential for the finite element modelling of the stress/strain distributions in finger-pad during vibratory loading, which is important in exploring the mechanism of hand-arm vibration syndrome. In conventional procedures, skin and subcutaneous tissue have to be separated for testing the viscoelastic properties. In this study, a novel method has been proposed to simultaneously determine the viscoelastic properties of skin and subcutaneous tissue in uniaxial stress relaxation tests. A mathematical approach has been derived to obtain the creep and relaxation characteristics of skin and subcutaneous tissue using uniaxial stress relaxation data of skin/subcutaneous composite specimens. The micro-structures of collagen fiber networks in the soft tissue, which underline the tissue mechanical characteristics, will be intact in the proposed method. Therefore, the viscoelastic properties of soft tissues obtained using the proposed method would be more physiologically relevant than those obtained using the conventional method. The proposed approach has been utilized to measure the viscoelastic properties of soft tissues of pig. The relaxation curves of pig skin and subcutaneous tissue obtained in the current study agree well with those in literature. Using the proposed approach, reliable material properties of soft tissues can be obtained in a cost- and time-efficient manner, which simultaneously improves the physiological relevance.

  17. Functionalizable hydrogel microparticles of tunable size and stiffness for soft-tissue filler applications

    PubMed Central

    Chan, Ka Man Carmen; Li, Randolph H.; Chapman, Joseph W.; Trac, Eric M.; Kobler, James B.; Zeitels, Steven M.; Langer, Robert; Karajanagi, Sandeep S.

    2014-01-01

    Particle size, stiffness and surface functionality are important in determining the injection site, safety and efficacy of injectable soft-tissue fillers. Methods to produce soft injectable biomaterials with controlled particle characteristics are therefore desirable. Here we report a method based on suspension photopolymerization and semi-interpenetrating network (semi-IPN) to synthesize soft, functionalizable, spherical hydrogel microparticles (MP) of independently tunable size and stiffness. MP were prepared using acrylated forms of polyethylene glycol (PEG), gelatin and hyaluronic acid. Semi-IPN MP of PEG-diacrylate and PEG were used to study the effect of process parameters on particle characteristics. The process parameters were systematically varied to produce MP with size ranging from 115 to 515 μm and stiffness ranging from 190 to 1600 Pa. In vitro studies showed that the MP thus prepared were cytocompatible. The ratio and identity of the polymers used to make the semi-IPN MP were varied to control their stiffness and to introduce amine groups for potential functionalization. Slow-release polymeric particles loaded with Rhodamine or dexamethasone were incorporated in the MP as a proof-of-principle of drug incorporation and release from the MP. This work has implications in preparing injectable biomaterials of natural or synthetic polymers for applications as soft-tissue fillers. PMID:24561708

  18. Dielectric Elastomer Actuators for Soft Wave-Handling Systems.

    PubMed

    Wang, Tao; Zhang, Jinhua; Hong, Jun; Wang, Michael Yu

    2017-03-01

    This article presents a soft handling system inspired by the principle of the natural wave (named Wave-Handling system) aiming to offer a soft solution to delicately transport and sort fragile items such as fruits, vegetables, biological tissues in food, and biological industries. The system consists of an array of hydrostatically coupled dielectric elastomer actuators (HCDEAs). Due to the electrostriction property of dielectric elastomers, the handling system can be controlled by electric voltage rather than the cumbersome pneumatic system. To study the working performance of the Wave-Handling system and how the performance can be improved, the basic properties of HCDEA are investigated through experiments. We find that the HCDEA exhibits some delay and hysteretic characteristics when activated by periodic voltage and the characteristics are influenced by the frequency and external force also. All this will affect the performance of the Wave-Handling system. However, the electric control, simple structure, light weight, and low cost of the soft handling system show great potential to move from laboratory to practical application. As a proof of design concept, a simply made prototype of the handling system is controlled to generate a parallel moving wave to manipulate a ball. Based on the experimental results, the improvements and future work are discussed and we believe this work will provide inspiration for soft robotic engineering.

  19. Chronic laminitis: strategic hoof wall resection.

    PubMed

    Rucker, Amy

    2010-04-01

    In the chronic-laminitic foot, severe soft-tissue compression and compromised circulation can result in osteitis and sepsis at the margin of the distal phalanx. Resultant inflammation and sepsis may cause the coronary corium to swell, drain, or separate from the hoof capsule, usually within 8 weeks of laminitis onset. Slow-onset cases of soft-tissue impingement can develop secondary to distal phalanx displacement due to lack of wall attachment. With either presentation, partial upper wall resection is required to reverse compression and vascular impingement by the hoof capsule. If the pathology is not overwhelming, the area reepithelializes and grows attached tubular horn. Firm bandaging and restricted exercise until tubular horn has regrown enhances recovery and the return of a strong hoof. Copyright 2010 Elsevier Inc. All rights reserved.

  20. Carbon nanotubes and graphene towards soft electronics

    NASA Astrophysics Data System (ADS)

    Chae, Sang Hoon; Lee, Young Hee

    2014-04-01

    Although silicon technology has been the main driving force for miniaturizing device dimensions to improve cost and performance, the current application of Si to soft electronics (flexible and stretchable electronics) is limited due to material rigidity. As a result, various prospective materials have been proposed to overcome the rigidity of conventional Si technology. In particular, nano-carbon materials such as carbon nanotubes (CNTs) and graphene are promising due to outstanding elastic properties as well as an excellent combination of electronic, optoelectronic, and thermal properties compared to conventional rigid silicon. The uniqueness of these nano-carbon materials has opened new possibilities for soft electronics, which is another technological trend in the market. This review covers the recent progress of soft electronics research based on CNTs and graphene. We discuss the strategies for soft electronics with nano-carbon materials and their preparation methods (growth and transfer techniques) to devices as well as the electrical characteristics of transparent conducting films (transparency and sheet resistance) and device performances in field effect transistor (FET) (structure, carrier type, on/off ratio, and mobility). In addition to discussing state of the art performance metrics, we also attempt to clarify trade-off issues and methods to control the trade-off on/off versus mobility). We further demonstrate accomplishments of the CNT network in flexible integrated circuits on plastic substrates that have attractive characteristics. A future research direction is also proposed to overcome current technological obstacles necessary to realize commercially feasible soft electronics.

  1. Carbon nanotubes and graphene towards soft electronics.

    PubMed

    Chae, Sang Hoon; Lee, Young Hee

    2014-01-01

    Although silicon technology has been the main driving force for miniaturizing device dimensions to improve cost and performance, the current application of Si to soft electronics (flexible and stretchable electronics) is limited due to material rigidity. As a result, various prospective materials have been proposed to overcome the rigidity of conventional Si technology. In particular, nano-carbon materials such as carbon nanotubes (CNTs) and graphene are promising due to outstanding elastic properties as well as an excellent combination of electronic, optoelectronic, and thermal properties compared to conventional rigid silicon. The uniqueness of these nano-carbon materials has opened new possibilities for soft electronics, which is another technological trend in the market. This review covers the recent progress of soft electronics research based on CNTs and graphene. We discuss the strategies for soft electronics with nano-carbon materials and their preparation methods (growth and transfer techniques) to devices as well as the electrical characteristics of transparent conducting films (transparency and sheet resistance) and device performances in field effect transistor (FET) (structure, carrier type, on/off ratio, and mobility). In addition to discussing state of the art performance metrics, we also attempt to clarify trade-off issues and methods to control the trade-off on/off versus mobility). We further demonstrate accomplishments of the CNT network in flexible integrated circuits on plastic substrates that have attractive characteristics. A future research direction is also proposed to overcome current technological obstacles necessary to realize commercially feasible soft electronics.

  2. A rate insensitive linear viscoelastic model for soft tissues

    PubMed Central

    Zhang, Wei; Chen, Henry Y.; Kassab, Ghassan S.

    2012-01-01

    It is well known that many biological soft tissues behave as viscoelastic materials with hysteresis curves being nearly independent of strain rate when loading frequency is varied over a large range. In this work, the rate insensitive feature of biological materials is taken into account by a generalized Maxwell model. To minimize the number of model parameters, it is assumed that the characteristic frequencies of Maxwell elements form a geometric series. As a result, the model is characterized by five material constants: μ0, τ, m, ρ and β, where μ0 is the relaxed elastic modulus, τ the characteristic relaxation time, m the number of Maxwell elements, ρ the gap between characteristic frequencies, and β = μ1/μ0 with μ1 being the elastic modulus of the Maxwell body that has relaxation time τ. The physical basis of the model is motivated by the microstructural architecture of typical soft tissues. The novel model shows excellent fit of relaxation data on the canine aorta and captures the salient features of vascular viscoelasticity with significantly fewer model parameters. PMID:17512585

  3. Heat transport modelling in EXTRAP T2R

    NASA Astrophysics Data System (ADS)

    Frassinetti, L.; Brunsell, P. R.; Cecconello, M.; Drake, J. R.

    2009-02-01

    A model to estimate the heat transport in the EXTRAP T2R reversed field pinch (RFP) is described. The model, based on experimental and theoretical results, divides the RFP electron heat diffusivity χe into three regions, one in the plasma core, where χe is assumed to be determined by the tearing modes, one located around the reversal radius, where χe is assumed not dependent on the magnetic fluctuations and one in the extreme edge, where high χe is assumed. The absolute values of the core and of the reversal χe are determined by simulating the electron temperature and the soft x-ray and by comparing the simulated signals with the experimental ones. The model is used to estimate the heat diffusivity and the energy confinement time during the flat top of standard plasmas, of deep F plasmas and of plasmas obtained with the intelligent shell.

  4. Biodegradable packing materials from hydrolysates of collagen waste proteins.

    PubMed

    Langmaier, F; Mokrejs, P; Kolomaznik, K; Mladek, M

    2008-01-01

    Enzymatic hydrolysates of waste collagen proteins (H), from current industrial manufacture (leather, edible meat product casings, etc.) of mean molecular mass 20-30 kDa by a reaction with dialdehyde starch (DAS), produces hydrogels applicable as biodegradable (or even edible) packaging materials for food, cosmetic and pharmaceutical products. Thermo-reversibility of prepared hydrogels is given by concentrations of H and DAS in a reaction mixture. At concentrations of H 25-30% (w/w) and that of DAS 15-20% (related to weight of hydrolysate), thermo-reversible hydrogels arise, which can be processed into packaging materials by a technique similar to that of soft gelatin capsules (SGC). Exceeding the limit of 20% DAS leads to hydrogels that are thermo-reversible only in part, a further increase in DAS concentration then leads to thermo-irreversible gels whose processing into biodegradable packaging materials necessitates employment of other procedures.

  5. Complications in reverse shoulder arthroplasty

    PubMed Central

    Barco, Raul; Savvidou, Olga D.; Sperling, John W.; Sanchez-Sotelo, Joaquín; Cofield, Robert H.

    2016-01-01

    The reported rate of complications of reverse shoulder arthroplasty (RSA) seems to be higher than the complication rate of anatomical total shoulder arthroplasty. The reported overall complication rate of primary RSA is approximately 15%; when RSA is used in the revision setting, the complication rate may approach 40%. The most common complications of RSA include instability, infection, notching, loosening, nerve injury, acromial and scapular spine fractures, intra-operative fractures and component disengagement. Careful attention to implant design and surgical technique, including implantation of components in the correct version and height, selection of the best glenosphere-humeral bearing match, avoidance of impingement, and adequate management of the soft tissues will hopefully translate in a decreasing number of complications in the future. Cite this article: Barco R, Savvidou OD, Sperling JW, Sanchez-Sotelo J, Cofield RH. Complications in reverse shoulder arthroplasty. EFORT Open Rev 2016;1:72-80. DOI: 10.1302/2058-5241.1.160003. PMID:28461931

  6. Complications in reverse shoulder arthroplasty.

    PubMed

    Barco, Raul; Savvidou, Olga D; Sperling, John W; Sanchez-Sotelo, Joaquín; Cofield, Robert H

    2016-03-01

    The reported rate of complications of reverse shoulder arthroplasty (RSA) seems to be higher than the complication rate of anatomical total shoulder arthroplasty.The reported overall complication rate of primary RSA is approximately 15%; when RSA is used in the revision setting, the complication rate may approach 40%.The most common complications of RSA include instability, infection, notching, loosening, nerve injury, acromial and scapular spine fractures, intra-operative fractures and component disengagement.Careful attention to implant design and surgical technique, including implantation of components in the correct version and height, selection of the best glenosphere-humeral bearing match, avoidance of impingement, and adequate management of the soft tissues will hopefully translate in a decreasing number of complications in the future. Cite this article: Barco R, Savvidou OD, Sperling JW, Sanchez-Sotelo J, Cofield RH. Complications in reverse shoulder arthroplasty. EFORT Open Rev 2016;1:72-80. DOI: 10.1302/2058-5241.1.160003.

  7. Predictors of participant engagement and naloxone utilization in a community-based naloxone distribution program.

    PubMed

    Rowe, Christopher; Santos, Glenn-Milo; Vittinghoff, Eric; Wheeler, Eliza; Davidson, Peter; Coffin, Philip O

    2015-08-01

    To describe characteristics of participants and overdose reversals associated with a community-based naloxone distribution program and identify predictors of obtaining naloxone refills and using naloxone for overdose reversal. Bivariate statistical tests were used to compare characteristics of participants who obtained refills and reported overdose reversals versus those who did not. We fitted multiple logistic regression models to identify predictors of refills and reversals; zero-inflated multiple Poisson regression models were used to identify predictors of number of refills and reversals. San Francisco, California, USA. Naloxone program participants registered and reversals reported from 2010 to 2013. Baseline characteristics of participants and reported characteristics of reversals. A total of 2500 participants were registered and 702 reversals were reported from 2010 to 2013. Participants who had witnessed an overdose [adjusted odds ratio (AOR)=2.02, 95% confidence interval (CI)= 1.53-2.66; AOR = 2.73, 95% CI = 1.73-4.30] or used heroin (AOR = 1.85, 95% CI =  1.44-2.37; AOR = 2.19, 95% CI = 1.54-3.13) or methamphetamine (AOR=1.71, 95% CI=1.37-2.15; AOR=1.61, 95% CI=1.18-2.19) had higher odds of obtaining a refill and reporting a reversal, respectively. African American (AOR = 0.63, 95% CI = 0.45-0.88) and Latino (AOR = 0.65, 95% CI =  0.43-1.00) participants had lower odds of obtaining a naloxone refill, whereas Latino participants who obtained at least one refill reported a higher number of refills [incidence rate ratio (IRR) = 1.33 (1.05-1.69)]. Community naloxone distribution programs are capable of reaching sizeable populations of high-risk individuals and facilitating large numbers of overdose reversals. Community members most likely to engage with a naloxone program and use naloxone to reverse an overdose are active drug users. © 2015 Society for the Study of Addiction.

  8. Neural correlates of alcohol-approach bias in alcohol addiction: the spirit is willing but the flesh is weak for spirits.

    PubMed

    Wiers, Corinde E; Stelzel, Christine; Park, Soyoung Q; Gawron, Christiane K; Ludwig, Vera U; Gutwinski, Stefan; Heinz, Andreas; Lindenmeyer, Johannes; Wiers, Reinout W; Walter, Henrik; Bermpohl, Felix

    2014-02-01

    Behavioral studies have shown an alcohol-approach bias in alcohol-dependent patients: the automatic tendency to faster approach than avoid alcohol compared with neutral cues, which has been associated with craving and relapse. Although this is a well-studied psychological phenomenon, little is known about the brain processes underlying automatic action tendencies in addiction. We examined 20 alcohol-dependent patients and 17 healthy controls with functional magnetic resonance imaging (fMRI), while performing an implicit approach-avoidance task. Participants pushed and pulled pictorial cues of alcohol and soft-drink beverages, according to a content-irrelevant feature of the cue (landscape/portrait). The critical fMRI contrast regarding the alcohol-approach bias was defined as (approach alcohol>avoid alcohol)>(approach soft drink>avoid soft drink). This was reversed for the avoid-alcohol contrast: (avoid alcohol>approach alcohol)>(avoid soft drink>approach soft drink). In comparison with healthy controls, alcohol-dependent patients had stronger behavioral approach tendencies for alcohol cues than for soft-drink cues. In the approach, alcohol fMRI contrast patients showed larger blood-oxygen-level-dependent responses in the nucleus accumbens and medial prefrontal cortex, regions involved in reward and motivational processing. In alcohol-dependent patients, alcohol-craving scores were positively correlated with activity in the amygdala for the approach-alcohol contrast. The dorsolateral prefrontal cortex was not activated in the avoid-alcohol contrast in patients vs controls. Our data suggest that brain regions that have a key role in reward and motivation are associated with the automatic alcohol-approach bias in alcohol-dependent patients.

  9. Ion irradiation induced effects and magnetization reversal mechanism in (Ni80Fe20)1-xCox nanowires and nanotubes

    NASA Astrophysics Data System (ADS)

    Ahmad, Naeem; Iqbal, Javed; Chen, J. Y.; Hussain, Asim; Shi, D. W.; Han, X. F.

    2015-03-01

    The effect of Co on the ferromagnetic characteristics of the Ni80Fe20 nanocylinders having zero magnetostriction and soft magnetic nature is an interesting field of research. The (Ni80Fe20)1-xCox nanocylinders have been prepared by electrodeposition into commercially available anodized aluminum oxide (AAO) nanoporous templates. The analysis of magnetization reversal from the angular dependence of coercivity has been studied in detail. This angular dependence of coercivity has shown a transition from curling to nucleation mode as a function of field angle for all (Ni80Fe20)1-xCox nanocylinders depending upon the critical angle. The shape anisotropy, dipole-dipole interactions, surface effects and magnetocrystalline anisotropy have been found to play an effective role for the spontaneous magnetization in nanowires and nanotubes. It has been interestingly observed that the magnetostatic interactions or dipole-dipole interactions are dominant in nanocylinders regardless of its geometry. Furthermore, the prepared samples have been irradiated with He2+ ions (energy E=2 MeV, fluence=1014 ions/cm2 and ion current=16 nA) at room temperature using a 5-UDH-2pelletron tandem accelerator. The irradiations have created defects and these defects have induced changes in magnetization as a result an increase in coercivity as function of the ion fluences is observed. Such kind of behavior in coercivity enhancement and magnetization reduction can also be attributed to the stress relaxation and percolation in nonuniform states of ferromagnetic alloys, respectively.

  10. Proton-irradiation technology for high-frequency high-current silicon welding diode manufacturing

    NASA Astrophysics Data System (ADS)

    Lagov, P. B.; Drenin, A. S.; Zinoviev, M. A.

    2017-05-01

    Different proton irradiation regimes were tested to provide more than 20 kHz-frequency, soft reverse recovery “snap-less” behavior, low forward voltage drop and leakage current for 50 mm diameter 7 kA/400 V welding diode Al/Si/Mo structure. Silicon diode with such parameters is very suitable for high frequency resistance welding machines of new generation for robotic welding.

  11. Nonlinear dynamics of a circular piezoelectric plate for vibratory energy harvesting

    NASA Astrophysics Data System (ADS)

    Yuan, Tian-Chen; Yang, Jian; Chen, Li-Qun

    2018-06-01

    Nonlinear behaviors are investigated for a vibration-based energy harvester. The harvester consists of a circular composite plate with the clamped boundary, a proof mass and two steel rings. The lumped parameter model of the harvester is established and the parameters are identified from the experiment. The measured nonlinear behaviors can be approximately described by the lumped model. Both the experimental and the numerical results demonstrate that the circular plate harvester has soft characteristics under low excitation and both hard characteristics and soft characteristics under high excitation. The experimental results show that the output voltage can achieve over 35 V (about 50 mW) and more than 14 Hz of bandwidth with 25 kΩ load resistance.

  12. Dynamic characteristics of 4H-SiC drift step recovery diodes

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

    Ivanov, P. A., E-mail: Pavel.Ivanov@mail.ioffe.ru; Kon’kov, O. I.; Samsonova, T. P.

    The dynamic characteristics of 4H-SiC p{sup +}–p–n{sub 0}–n{sup +} diodes are experimentally studied in the pulsed modes characteristic of the operation of drift step recovery diodes (DSRD-mode). The effect of the subnanosecond termination of the reverse current maintained by electron-hole plasma preliminarily pumped by a forward current pulse is analyzed in detail. The influence exerted on the DSRD effect by the amplitude of reverse-voltage pulses, the amplitude and duration of forward-current pulses, and the time delay between the forward and reverse pulses is demonstrated and accounted for.

  13. Improved confinement region without large magnetohydrodynamic activity in TPE-RX reversed-field pinch plasma

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

    Yambe, Kiyoyuki; Hirano, Yoichi; Sakakita, Hajime

    2014-11-15

    We found that spontaneous improved confinement was brought about depending on the operating region in the Toroidal Pinch Experiment-Reversed eXperiment (TPE-RX) reversed-field pinch plasma [Y. Yagi et al., Fusion Eng. Des. 45, 421 (1999)]. Gradual decay of the toroidal magnetic field at plasma surface B{sub tw} reversal makes it possible to realize a prolonged discharge, and the poloidal beta value and energy confinement time increase in the latter half of the discharge, where reversal and pinch parameters become shallow and low, respectively. In the latter half of the discharge, the plasma current and volume-averaged toroidal magnetic field 〈B{sub t}〉 increasemore » again, the electron density slowly decays, the electron temperature and soft X-ray radiation intensity increase, and the magnetic fluctuations are markedly reduced. In this period of improved confinement, the value of (〈B{sub t}〉-B{sub tw})/B{sub pw}, where B{sub pw} is the poloidal magnetic field at the plasma surface, stays almost constant, which indicates that the dynamo action occurs without large magnetohydrodynamic activities.« less

  14. Unified viscoelasticity: Applying discrete element models to soft tissues with two characteristic times.

    PubMed

    Anssari-Benam, Afshin; Bucchi, Andrea; Bader, Dan L

    2015-09-18

    Discrete element models have often been the primary tool in investigating and characterising the viscoelastic behaviour of soft tissues. However, studies have employed varied configurations of these models, based on the choice of the number of elements and the utilised formation, for different subject tissues. This approach has yielded a diverse array of viscoelastic models in the literature, each seemingly resulting in different descriptions of viscoelastic constitutive behaviour and/or stress-relaxation and creep functions. Moreover, most studies do not apply a single discrete element model to characterise both stress-relaxation and creep behaviours of tissues. The underlying assumption for this disparity is the implicit perception that the viscoelasticity of soft tissues cannot be described by a universal behaviour or law, resulting in the lack of a unified approach in the literature based on discrete element representations. This paper derives the constitutive equation for different viscoelastic models applicable to soft tissues with two characteristic times. It demonstrates that all possible configurations exhibit a unified and universal behaviour, captured by a single constitutive relationship between stress, strain and time as: σ+Aσ̇+Bσ¨=Pε̇+Qε¨. The ensuing stress-relaxation G(t) and creep J(t) functions are also unified and universal, derived as [Formula: see text] and J(t)=c2+(ε0-c2)e(-PQt)+σ0Pt, respectively. Application of these relationships to experimental data is illustrated for various tissues including the aortic valve, ligament and cerebral artery. The unified model presented in this paper may be applied to all tissues with two characteristic times, obviating the need for employing varied configurations of discrete element models in preliminary investigation of the viscoelastic behaviour of soft tissues. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Fatigue characteristics of carbon nanotube blocks under compression

    NASA Astrophysics Data System (ADS)

    Suhr, J.; Ci, L.; Victor, P.; Ajayan, P. M.

    2008-03-01

    In this paper we investigate the mechanical response from repeated high compressive strains on freestanding, long, vertically aligned multiwalled carbon nanotube membranes and show that the arrays of nanotubes under compression behave very similar to soft tissue and exhibit viscoelastic behavior. Under compressive cyclic loading, the mechanical response of nanotube blocks shows initial preconditioning and hysteresis characteristic of viscoeleastic materials. Furthermore, no fatigue failure is observed even at high strain amplitudes up to half million cycles. The outstanding fatigue life and extraordinary soft tissue-like mechanical behavior suggest that properly engineered carbon nanotube structures could mimic artificial muscles.

  16. Exploring pH-Sensitive Hydrogels Using an Ionic Soft Contact Lens: An Activity Using Common Household Materials

    ERIC Educational Resources Information Center

    Chen, Yueh-Huey; He, Yu-Chi; Yaung, Jing-Fun

    2014-01-01

    Hydrogels of the so-called smart polymers or environment-sensitive polymers are important modern biomaterials. Herein, we describe a hands-on activity to explore the pH-responsive characteristics of hydrogels using a commercially available ionic soft contact lens that is a hydrogel of poly(2-hydroxyethyl methacrylate-"co"-methacrylic…

  17. "Second Generation" E-Learning: Characteristics and Design Principles for Supporting Management Soft-Skills Development

    ERIC Educational Resources Information Center

    Adams, Jean; Morgan, Gareth

    2007-01-01

    This article develops the concept of "second generation" e-learning as a new paradigm for thinking about online learning. Whereas "first generation" approaches have been effective for developing technical skills, the same approach has not proven effective for developing management soft-skills (e.g., in the field of leadership education). The…

  18. Quality requirements of soft red winter wheat for making northern-style Chinese steamed bread

    USDA-ARS?s Scientific Manuscript database

    Flours of 19 soft red winter (SRW) wheat varieties having protein contents of 6.6 to 9.9% were used to determine the suitability of SRW wheat for making steamed bread and the influences of flour characteristics on the quality attributes of steamed bread. Fourteen varieties produced steamed bread of ...

  19. Association between sugar-sweetened and artificially sweetened soft drinks and type 2 diabetes: systematic review and dose-response meta-analysis of prospective studies.

    PubMed

    Greenwood, D C; Threapleton, D E; Evans, C E L; Cleghorn, C L; Nykjaer, C; Woodhead, C; Burley, V J

    2014-09-14

    The intake of sugar-sweetened soft drinks has been reported to be associated with an increased risk of type 2 diabetes, but it is unclear whether this is because of the sugar content or related lifestyle factors, whether similar associations hold for artificially sweetened soft drinks, and how these associations are related to BMI. We aimed to conduct a systematic literature review and dose-response meta-analysis of evidence from prospective cohorts to explore these issues. We searched multiple sources for prospective studies on sugar-sweetened and artificially sweetened soft drinks in relation to the risk of type 2 diabetes. Data were extracted from eleven publications on nine cohorts. Consumption values were converted to ml/d, permitting the exploration of linear and non-linear dose-response trends. Summary relative risks (RR) were estimated using a random-effects meta-analysis. The summary RR for sugar-sweetened and artificially sweetened soft drinks were 1·20/330 ml per d (95 % CI 1·12, 1·29, P< 0·001) and 1·13/330 ml per d (95 % CI 1·02, 1·25, P= 0·02), respectively. The association with sugar-sweetened soft drinks was slightly lower in studies adjusting for BMI, consistent with BMI being involved in the causal pathway. There was no evidence of effect modification, though both these comparisons lacked power. Overall between-study heterogeneity was high. The included studies were observational, so their results should be interpreted cautiously, but findings indicate a positive association between sugar-sweetened soft drink intake and type 2 diabetes risk, attenuated by adjustment for BMI. The trend was less consistent for artificially sweetened soft drinks. This may indicate an alternative explanation, such as lifestyle factors or reverse causality. Future research should focus on the temporal nature of the association and whether BMI modifies or mediates the association.

  20. Hard-Diet Feeding Recovers Neurogenesis in the Subventricular Zone and Olfactory Functions of Mice Impaired by Soft-Diet Feeding

    PubMed Central

    Utsugi, Chizuru; Miyazono, Sadaharu; Osada, Kazumi; Sasajima, Hitoshi; Noguchi, Tomohiro; Matsuda, Mitsuyoshi; Kashiwayanagi, Makoto

    2014-01-01

    The subventricular zone (SVZ) generates an immense number of neurons even during adulthood. These neurons migrate to the olfactory bulb (OB) and differentiate into granule cells and periglomerular cells. The information broadcast by general odorants is received by the olfactory sensory neurons and transmitted to the OB. Recent studies have shown that a reduction of mastication impairs both neurogenesis in the hippocampus and brain functions. To examine these effects, we first measured the difference in Fos-immunoreactivity (Fos-ir) at the principal sensory trigeminal nucleus (Pr5), which receives intraoral touch information via the trigeminal nerve, when female adult mice ingested a hard or soft diet to explore whether soft-diet feeding could mimic impaired mastication. Ingestion of a hard diet induced greater expression of Fos-ir cells at the Pr5 than did a soft diet or no diet. Bromodeoxyuridine-immunoreactive (BrdU-ir) structures in sagittal sections of the SVZ and in the OB of mice fed a soft or hard diet were studied to explore the effects of changes in mastication on newly generated neurons. After 1 month, the density of BrdU-ir cells in the SVZ and OB was lower in the soft-diet-fed mice than in the hard-diet-fed mice. The odor preferences of individual female mice to butyric acid were tested in a Y-maze apparatus. Avoidance of butyric acid was reduced by the soft-diet feeding. We then explored the effects of the hard-diet feeding on olfactory functions and neurogenesis in the SVZ of mice impaired by soft-diet feeding. At 3 months of hard-diet feeding, avoidance of butyric acid was reversed and responses to odors and neurogenesis were recovered in the SVZ. The present results suggest that feeding with a hard diet improves neurogenesis in the SVZ, which in turn enhances olfactory function at the OB. PMID:24817277

  1. Features of current-voltage characteristic of nonequilibrium trench MOS barrier Schottky diode

    NASA Astrophysics Data System (ADS)

    Mamedov, R. K.; Aslanova, A. R.

    2018-06-01

    The trench MOS barrier Schottky diodes (TMBS diode) under the influence of the voltage drop of the additional electric field (AEF) appearing in the near-contact region of the semiconductor are in a nonequilibrium state and their closed external circuit flows currents in the absence of an external voltage. When an external voltage is applied to the TMBS diode, the current transmission is described by the thermionic emission theory with a specific feature. Both forward and reverse I-V characteristics of the TMBS diode consist of two parts. In the initial first part of the forward I-V characteristic there are no forward currents, but reverse saturation currents flow, in its subsequent second part the currents increase exponentially with the voltage. In the initial first part of the reverse I-V characteristic, the currents increase in an abrupt way and in the subsequent second part the saturation currents flow under the action of the image force. The mathematical expressions for forward and reverse I-V characteristic of the TMBS diode and also narrow or nanostructure Schottky diode are proposed, which are in good agreement with the results of experimental and calculated I-V characteristics.

  2. The Elusive Soft Emission from Hard X-ray Symbiotic System RT Cru

    NASA Astrophysics Data System (ADS)

    Karovska, Margarita

    2014-09-01

    RT Cru is a fascinating member of a new class of hard X-ray emitting symbiotic binaries showing X-ray emission extending to over 50keV. While its hard X-ray emission has been studied in detail, the soft component of the spectrum, including flares, remains elusive, since previous observations have focused on the high-energy regime. We propose Chandra HRC-S/LETG observations to determine the spatial, spectral, and temporal characteristics of the source of the soft X-ray emission with a goal to establish the origin of the soft component, and determine whether and how it is tied to the hard component. Determining the origin of the soft emission is a crucial piece of the puzzle to understanding the geometry, energetics, and the environment of WD accretion in this class of symbiotic systems.

  3. Web mining in soft computing framework: relevance, state of the art and future directions.

    PubMed

    Pal, S K; Talwar, V; Mitra, P

    2002-01-01

    The paper summarizes the different characteristics of Web data, the basic components of Web mining and its different types, and the current state of the art. The reason for considering Web mining, a separate field from data mining, is explained. The limitations of some of the existing Web mining methods and tools are enunciated, and the significance of soft computing (comprising fuzzy logic (FL), artificial neural networks (ANNs), genetic algorithms (GAs), and rough sets (RSs) are highlighted. A survey of the existing literature on "soft Web mining" is provided along with the commercially available systems. The prospective areas of Web mining where the application of soft computing needs immediate attention are outlined with justification. Scope for future research in developing "soft Web mining" systems is explained. An extensive bibliography is also provided.

  4. Soft pair excitations and double-log divergences due to carrier interactions in graphene

    NASA Astrophysics Data System (ADS)

    Lewandowski, Cyprian; Levitov, L. S.

    2018-03-01

    Interactions between charge carriers in graphene lead to logarithmic renormalization of observables mimicking the behavior known in (3+1)-dimensional quantum electrodynamics (QED). Here we analyze soft electron-hole (e -h ) excitations generated as a result of fast charge dynamics, a direct analog of the signature QED effect—multiple soft photons produced by the QED vacuum shakeup. We show that such excitations are generated in photon absorption, when a photogenerated high-energy e -h pair cascades down in energy and gives rise to multiple soft e -h excitations. This fundamental process is manifested in a double-log divergence in the emission rate of soft pairs and a characteristic power-law divergence in their energy spectrum of the form 1/ω ln(ω/Δ ) . Strong carrier-carrier interactions make pair production a prominent pathway in the photoexcitation cascade.

  5. Reverse leakage current characteristics of InGaN/GaN multiple quantum well ultraviolet/blue/green light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Zhou, Shengjun; Lv, Jiajiang; Wu, Yini; Zhang, Yuan; Zheng, Chenju; Liu, Sheng

    2018-05-01

    We investigated the reverse leakage current characteristics of InGaN/GaN multiple quantum well (MQW) near-ultraviolet (NUV)/blue/green light-emitting diodes (LEDs). Experimental results showed that the NUV LED has the smallest reverse leakage current whereas the green LED has the largest. The reason is that the number of defects increases with increasing nominal indium content in InGaN/GaN MQWs. The mechanism of the reverse leakage current was analyzed by temperature-dependent current–voltage measurement and capacitance–voltage measurement. The reverse leakage currents of NUV/blue/green LEDs show similar conduction mechanisms: at low temperatures, the reverse leakage current of these LEDs is attributed to variable-range hopping (VRH) conduction; at high temperatures, the reverse leakage current of these LEDs is attributed to nearest-neighbor hopping (NNH) conduction, which is enhanced by the Poole–Frenkel effect.

  6. Swimming Back and Forth Using Planar Flagellar Propulsion at Low Reynolds Numbers.

    PubMed

    Khalil, Islam S M; Tabak, Ahmet Fatih; Hamed, Youssef; Mitwally, Mohamed E; Tawakol, Mohamed; Klingner, Anke; Sitti, Metin

    2018-02-01

    Peritrichously flagellated Escherichia coli swim back and forth by wrapping their flagella together in a helical bundle. However, other monotrichous bacteria cannot swim back and forth with a single flagellum and planar wave propagation. Quantifying this observation, a magnetically driven soft two-tailed microrobot capable of reversing its swimming direction without making a U-turn trajectory or actively modifying the direction of wave propagation is designed and developed. The microrobot contains magnetic microparticles within the polymer matrix of its head and consists of two collinear, unequal, and opposite ultrathin tails. It is driven and steered using a uniform magnetic field along the direction of motion with a sinusoidally varying orthogonal component. Distinct reversal frequencies that enable selective and independent excitation of the first or the second tail of the microrobot based on their tail length ratio are found. While the first tail provides a propulsive force below one of the reversal frequencies, the second is almost passive, and the net propulsive force achieves flagellated motion along one direction. On the other hand, the second tail achieves flagellated propulsion along the opposite direction above the reversal frequency.

  7. Stimulus-Responsive Nanoparticles and Associated (Reversible) Polymorphism via Polymerization Induced Self-assembly (PISA).

    PubMed

    Pei, Yiwen; Lowe, Andrew B; Roth, Peter J

    2017-01-01

    Polymerization-induced self-assembly (PISA) is an extremely versatile method for the in situ preparation of soft-matter nanoparticles of defined size and morphologies at high concentrations, suitable for large-scale production. Recently, certain PISA-prepared nanoparticles have been shown to exhibit reversible polymorphism ("shape-shifting"), typically between micellar, worm-like, and vesicular phases (order-order transitions), in response to external stimuli including temperature, pH, electrolytes, and chemical modification. This review summarises the literature to date and describes molecular requirements for the design of stimulus-responsive nano-objects. Reversible pH-responsive behavior is rationalised in terms of increased solvation of reversibly ionized groups. Temperature-triggered order-order transitions, conversely, do not rely on inherently thermo-responsive polymers, but are explained based on interfacial LCST or UCST behavior that affects the volume fractions of the core and stabilizer blocks. Irreversible morphology transitions, on the other hand, can result from chemical post-modification of reactive PISA-made particles. Emerging applications and future research directions of this "smart" nanoparticle behavior are reviewed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Differential diagnosis between benign and malignant soft tissue tumors utilizing ultrasound parameters.

    PubMed

    Morii, Takeshi; Kishino, Tomonori; Shimamori, Naoko; Motohashi, Mitsue; Ohnishi, Hiroaki; Honya, Keita; Aoyagi, Takayuki; Tajima, Takashi; Ichimura, Shoichi

    2018-01-01

    Preoperative discrimination between benign and malignant soft tissue tumors is critical for the prevention of excess application of magnetic resonance imaging and biopsy as well as unplanned resection. Although ultrasound, including power Doppler imaging, is an easy, noninvasive, and cost-effective modality for screening soft tissue tumors, few studies have investigated reliable discrimination between benign and malignant soft tissue tumors. To establish a modality for discrimination between benign and malignant soft tissue tumors using ultrasound, we extracted the significant risk factors for malignancy based on ultrasound information from 40 malignant and 56 benign pathologically diagnosed soft tissue tumors and established a scoring system based on these risk factors. The maximum size, tumor margin, and vascularity evaluated using ultrasound were extracted as significant risk factors. Using the odds ratio from a multivariate regression model, a scoring system was established. Receiver operating characteristic analyses revealed a high area under the curve value (0.85), confirming the accuracy of the scoring system. Ultrasound is a useful modality for establishing the differential diagnosis between benign and malignant soft tissue tumors.

  9. Effect of Reverse Bias Stress on Leakage Currents and Breakdown Voltages of Solid Tantalum Capacitors

    NASA Technical Reports Server (NTRS)

    Teverovsky, Alexander A.

    2011-01-01

    The majority of solid tantalum capacitors are produced by high-temperature sintering of a fine tantalum powder around a tantalum wire followed by electrolytic anodization that forms a thin amorphous Ta2O5 dielectric layer and pyrolysis of manganese nitrite on the oxide to create a conductive manganese dioxide electrode. A contact to tantalum wire is used as anode terminal and to the manganese layer as a cathode terminal of the device. This process results in formation of an asymmetric Ta -- Ta2O5 -- MnO2 capacitor that has different characteristics at forward (positive bias applied to tantalum) and reverse (positive bias applied to manganese cathode) voltages. Reverse bias currents might be several orders of magnitude larger than forward leakage currents so I-V characteristics of tantalum capacitors resemble characteristics of semiconductor rectifiers. Asymmetric I-V characteristics of Ta -- anodic Ta2O5 systems have been observed at different top electrode materials including metals, electrolytes, conductive polymers, and manganese oxide thus indicating that this phenomenon is likely related to the specifics of the Ta -- Ta2O5 interface. There have been multiple attempts to explain rectifying characteristics of capacitors employing anodic tantalum pentoxide dielectrics. A brief review of works related to reverse bias (RB) behavior of tantalum capacitors shows that the mechanism of conduction in Ta -- Ta2O5 systems is still not clear and more testing and analysis is necessary to understand the processes involved. If tantalum capacitors behave just as rectifiers, then the assessment of the safe reverse bias operating conditions would be a relatively simple task. Unfortunately, these parts can degrade with time under reverse bias significantly, and this further complicates analysis of the I-V characteristics and establishing safe operating areas of the parts. On other hand, time dependence of reverse currents might provide additional information for investigation of the processes under reverse bias conditions. In practice, there were instances when, due to unforeseen events, the system operated at conditions when capacitors experience periodically a relatively small reverse bias for some time followed by normal, forward bias conditions. In such a case an assessment should be made on the degree to which these capacitors are degraded by application of low-voltage reverse bias, and whether this degradation can be reversed by normal operating conditions. In this study, reverse currents in different types of tantalum capacitors were monitored at different reverse voltages below 15%VR and temperatures in the range from room to 145 C for up to 150 hours to get better understanding of the degradation process and determine conditions favorable to the unstable mode of operation. The reversibility of RB degradation has been evaluated after operation of the capacitors at forward bias conditions. The effect of reverse bias stress (RBS) on reliability at normal operating conditions was evaluated using highly accelerated life testing at voltages of 1.5VR and 2 VR and by analysis of changes in distributions of breakdown voltages. Possible mechanisms of RB degradation are discussed.

  10. Effect-directed analysis via hyphenated high-performance thin-layer chromatography for bioanalytical profiling of sunflower leaves.

    PubMed

    Móricz, Ágnes M; Ott, Péter G; Yüce, Imanuel; Darcsi, András; Béni, Szabolcs; Morlock, Gertrud E

    2018-01-19

    High-performance thin-layer chromatography (HPTLC) coupled with effect-directed analysis was used for non-targeted screening of sunflower leaf extract for components exhibiting antioxidant, antibacterial and/or cholinesterase enzyme inhibitory effects. The active compounds were characterized by HPTLC-electrospray ionization-high resolution mass spectrometry (ESI-HRMS) and HPTLC-Direct Analysis in Real Time (DART)-MS/MS. The latter ambient ionization technique (less soft than ESI) resulted in oxidation and fragmentation products and characteristic fragment ions. NMR spectroscopy after targeted isolation via preparative normal phase flash chromatography and semi-preparative reversed phase high-performance liquid chromatography supported the identification of two diterpenes to be (-)-kaur-16-en-19-oic acid and 15-α-angeloyloxy-ent-kaur-16-en-19-oic acid. Both compounds found to be multi-potent as they inhibited acetylcholinesterase and butyrylcholinesterase and showed antibacterial effects against Gram-positive Bacillus subtilis and Gram-negative Aliivibrio fischeri bacteria. Kaurenoic acid was also active against the Gram-negative pepper pathogenic Xanthomonas euvesicatoria bacteria. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Treatment in Borderline Class III Malocclusion: Orthodontic Camouflage (Extraction) Versus Orthognathic Surgery.

    PubMed

    Rabie, A-Bakr M; Wong, Ricky W K; Min, G U

    2008-01-01

    To investigate the differences in morphological characteristics of borderline class III patients who had undergone camouflage orthodontic treatment or orthognathic surgery, and to compare the treatment effects between these two modalities. Cephalograms of 25 patients (13 orthodontic, 12 surgical) with class III malocclusion were analyzed. All had a pretreatment ANB angle greater than -5 masculine. Using discriminant analysis, only Holdaway angle was selected to differentiate patients in the pretreatment stage. Seventy-two per cent patients were correctly classified. In the orthodontic group, reverse overjet was corrected by retraction of the lower incisors and downward and backward rotation of the mandible. The surgical group was corrected by setback of the lower anterior dentoalveolus and uprighting of the lower incisors. No difference was found in posttreatment soft tissue measurements between the two groups. Twelve degree for the Holdaway angle can be a guideline in determining the treatment modalities for borderline class III patients, but the preferences of operators and patients are also important. (2) Both therapeutic options should highlight changes in the lower dentoalveolus and lower incisors. (3) Both treatment modalities can achieve satisfactory improvements to the people.

  12. Structural and magnetic depth profiles of magneto-ionic heterostructures beyond the interface limit

    DOE PAGES

    Gilbert, Dustin A.; Grutter, Alexander J.; Arenholz, Elke; ...

    2016-07-22

    Electric field control of magnetism provides a promising route towards ultralow power information storage and sensor technologies. The effects of magneto-ionic motion have been prominently featured in the modification of interface characteristics. Here, we demonstrate magnetoelectric coupling moderated by voltage-driven oxygen migration beyond the interface in relatively thick AlO x/GdO x/Co(15 nm) films. Oxygen migration and Co magnetization are quantitatively mapped with polarized neutron reflectometry under electro-thermal conditioning. The depth-resolved profiles uniquely identify interfacial and bulk behaviours and a semi-reversible control of the magnetization. Magnetometry measurements suggest changes in the microstructure which disrupt long-range ferromagnetic ordering, resulting in an additionalmore » magnetically soft phase. X-ray spectroscopy confirms changes in the Co oxidation state, but not in the Gd, suggesting that the GdO x transmits oxygen but does not source or sink it. These results together provide crucial insight into controlling magnetism via magneto-ionic motion, both at interfaces and throughout the bulk of the films.« less

  13. Generation of Well-Relaxed All-Atom Models of Large Molecular Weight Polymer Melts: A Hybrid Particle-Continuum Approach Based on Particle-Field Molecular Dynamics Simulations.

    PubMed

    De Nicola, Antonio; Kawakatsu, Toshihiro; Milano, Giuseppe

    2014-12-09

    A procedure based on Molecular Dynamics (MD) simulations employing soft potentials derived from self-consistent field (SCF) theory (named MD-SCF) able to generate well-relaxed all-atom structures of polymer melts is proposed. All-atom structures having structural correlations indistinguishable from ones obtained by long MD relaxations have been obtained for poly(methyl methacrylate) (PMMA) and poly(ethylene oxide) (PEO) melts. The proposed procedure leads to computational costs mainly related on system size rather than to the chain length. Several advantages of the proposed procedure over current coarse-graining/reverse mapping strategies are apparent. No parametrization is needed to generate relaxed structures of different polymers at different scales or resolutions. There is no need for special algorithms or back-mapping schemes to change the resolution of the models. This characteristic makes the procedure general and its extension to other polymer architectures straightforward. A similar procedure can be easily extended to the generation of all-atom structures of block copolymer melts and polymer nanocomposites.

  14. ChainMail based neural dynamics modeling of soft tissue deformation for surgical simulation.

    PubMed

    Zhang, Jinao; Zhong, Yongmin; Smith, Julian; Gu, Chengfan

    2017-07-20

    Realistic and real-time modeling and simulation of soft tissue deformation is a fundamental research issue in the field of surgical simulation. In this paper, a novel cellular neural network approach is presented for modeling and simulation of soft tissue deformation by combining neural dynamics of cellular neural network with ChainMail mechanism. The proposed method formulates the problem of elastic deformation into cellular neural network activities to avoid the complex computation of elasticity. The local position adjustments of ChainMail are incorporated into the cellular neural network as the local connectivity of cells, through which the dynamic behaviors of soft tissue deformation are transformed into the neural dynamics of cellular neural network. Experiments demonstrate that the proposed neural network approach is capable of modeling the soft tissues' nonlinear deformation and typical mechanical behaviors. The proposed method not only improves ChainMail's linear deformation with the nonlinear characteristics of neural dynamics but also enables the cellular neural network to follow the principle of continuum mechanics to simulate soft tissue deformation.

  15. Soft Plumbing: Direct-Writing and Controllable Perfusion of Tubular Soft Materials

    NASA Astrophysics Data System (ADS)

    Guenther, Axel; Omoruwa, Patricia; Chen, Haotian; McAllister, Arianna; Jeronimo, Mark; Malladi, Shashi; Hakimi, Navid; Cao, Li; Ramchandran, Arun

    2016-11-01

    Tubular and ductular structures are abundant in tissues in a wide variety of diameters, wall thicknesses, and compositions. In spite of their relevance to engineered tissues, organs-on-chips and soft robotics, the rapid and consistent preparation of tubular structures remains a challenge. Here, we use a microfabricated printhead to direct-write biopolymeric tubes with dimensional and compositional control. A biopolymer solution is introduced to the center layer of the printhead, and the confining fluids to the top and the bottom layers. The radially flowing biopolymer solution is sandwiched between confining solutions that initiate gelation, initially assuming the shape of a funnel until emerging through a cylindrical confinement as a continuous biopolymer tube. Tubular constructs of sodium alginate and collagen I were obtained with inner diameters (0.6-2.2mm) and wall thicknesses (0.1-0.4mm) in favorable agreement with predictions of analytical models. We obtained homogeneous tubes with smooth and buckled walls and heterotypic constructs that possessed compositions that vary along the tube circumference or radius. Ductular soft materials were reversibly hosted in 3D printed fluidic devices for the perfusion at well-defined transmural pressures to explore the rich variety of dynamical features associated with collapsible tubes that include buckling, complete collapse, and self-oscillation.

  16. Compact soft x-ray multichord camera: Design and initial operation

    NASA Astrophysics Data System (ADS)

    Franz, P.; Gadani, G.; Pasqualotto, R.; Marrelli, L.; Martin, P.; Spizzo, G.; Brunsell, P.; Chapman, B. E.; Paganucci, F.; Rossetti, P.; Xiao, C.

    2003-03-01

    A compact and low cost diagnostic for spatially resolved measurements of soft x-ray or total radiation emission has been designed and realized to be flexibly applied to different plasma physics experiments. Its reduced size (outer diameter=35 mm) makes it suited to a variety of devices. The line integrated emissivity (brightness) has been measured along up to 20 lines of sight, using an array of miniaturized silicon photodiodes. Preliminary prototypes of the diagnostic have been installed in the Madison Symmetric Torus reversed field pinch (RFP) device at University of Wisconsin and in the EXTRAP T2 RFP device at the Royal Institute of Technology in Stockholm. Application of the diagnostic to a gas-fed (argon, helium) magnetoplasma dynamic thruster (MPDT) with an external magnetic field will also be discussed.

  17. Exchange-coupled hard magnetic Fe-Co/CoPt nanocomposite films fabricated by electro-infiltration

    NASA Astrophysics Data System (ADS)

    Wen, Xiao; Andrew, Jennifer S.; Arnold, David P.

    2017-05-01

    This paper introduces a potentially scalable electro-infiltration process to produce exchange-coupled hard magnetic nanocomposite thin films. Fe-Co/CoPt nanocomposite films are fabricated by deposition of CoFe2O4 nanoparticles onto Si substrate, followed by electroplating of CoPt. Samples are subsequently annealed under H2 to reduce the CoFe2O4 to magnetically soft Fe-Co and also induce L10 ordering in the CoPt. Resultant films exhibit 0.97 T saturation magnetization, 0.70 T remanent magnetization, 127 kA/m coercivity and 21.8 kJ/m3 maximum energy density. First order reversal curve (FORC) analysis and δM plot are used to prove the exchange coupling between soft and hard magnetic phases.

  18. Value of the Strain Ratio on Ultrasonic Elastography for Differentiation of Benign and Malignant Soft Tissue Tumors.

    PubMed

    Hahn, Seok; Lee, Young Han; Lee, Seung Hyun; Suh, Jin-Suck

    2017-01-01

    The purpose of this study was to evaluate whether the strain ratio provides additional value to conventional visual elasticity scores in the differentiation of benign and malignant soft tissue tumors by ultrasonic elastography. The Institutional Review Board approved the protocol of this retrospective review. Seventy-three patients who underwent elastography and had a soft tissue mass pathologically confirmed by ultrasound-guided core biopsy or surgical excision were enrolled from April 2012 through October 2014. On elastography, elasticity scores were determined with a 5-point visual scale, and the strain ratio to adjacent soft tissue at the same depth was calculated. Tumors were divided into benign and malignant groups according to the pathologic diagnoses. Elasticity scores and strain ratios were compared between benign and malignant groups, and diagnostic performance was evaluated by receiver operating characteristic curves. Of the 73 patients, 40 had benign tumors, and 33 had malignant tumors. Strain ratios (P = .003) and elasticity scores (P = .048) were significantly different between pathologic results. The areas under the receiver operating characteristic curves were 0.700 (95% confidence interval, 0.581-0.802) for the strain ratio and 0.623 (95% confidence interval, 0.515-0.746) for elastography. The strain ratios of malignant soft tissue tumors were lower than those of benign tumors and showed better diagnostic performance than did elasticity scores. The strain ratio can be used as a diagnostic indicator to predict the malignant potential of soft tissue tumors. © 2016 by the American Institute of Ultrasound in Medicine.

  19. Soft skills turned into hard facts: nucleosome remodelling at developmental switches.

    PubMed

    Chioda, M; Becker, P B

    2010-07-01

    Nucleosome remodelling factors are regulators of DNA accessibility in chromatin and lubricators of all major functions of eukaryotic genomes. Their action is transient and reversible, yet can be decisive for irreversible cell-fate decisions during development. In addition to the well-known local actions of nucleosome remodelling factors during transcription initiation, more global and fundamental roles for remodelling complexes in shaping the epigenome during development are emerging.

  20. Fabrication and Characterization of Vertical Gallium Nitride Power Schottky Diodes on Bulk GaN Substrates FY2016

    DTIC Science & Technology

    2016-12-01

    2000 rpm to give a resist thickness of approximately 2 µm. Following resist exposure, a soft bake was performed at 95 °C for 60 s on a hot plate. The...resist was then exposed to UV light for 4.2 s while in contact with the mask. To perform image reversal, the exposed resist was baked at 105 °C for

  1. Slow Food: Sustained Impact of Harder Foods on the Reduction in Energy Intake over the Course of the Day

    PubMed Central

    Bolhuis, Dieuwerke P.; Forde, Ciarán G.; Cheng, Yuejiao; Xu, Haohuan; Martin, Nathalie; de Graaf, Cees

    2014-01-01

    Background Previous research has shown that oral processing characteristics like bite size and oral residence duration are related to the satiating efficiency of foods. Oral processing characteristics are influenced by food texture. Very little research has been done on the effect of food texture within solid foods on energy intake. Objectives The first objective was to investigate the effect of hardness of food on energy intake at lunch, and to link this effect to differences in food oral processing characteristics. The second objective was to investigate whether the reduction in energy intake at lunch will be compensated for in the subsequent dinner. Design Fifty subjects (11 male, BMI: 21±2 kg/m2, age: 24±2 y) participated in a cross-over study in which they consumed ad libitum from a lunch with soft foods or hard foods on two separate days. Oral processing characteristics at lunch were assessed by coding video records. Later on the same days, subjects consumed dinner ad libitum. Results Hard foods led to a ∼13% lower energy intake at lunch compared to soft foods (P<0.001). Hard foods were consumed with smaller bites, longer oral duration per gram food, and more chewing per gram food compared to the soft foods (P<0.05). Energy intake at dinner did not differ after both lunches (P = 0.16). Conclusions Hard foods led to reduced energy intake compared to soft foods, and this reduction in energy intake was sustained over the next meal. We argue that the differences in oral processing characteristics produced by the hardness of the foods explain the effect on intake. The sustained reduction in energy intake suggests that changes in food texture can be a helpful tool in reducing the overall daily energy intake. PMID:24695412

  2. Alpha particle-induced soft errors in microelectronic devices. I

    NASA Astrophysics Data System (ADS)

    Redman, D. J.; Sega, R. M.; Joseph, R.

    1980-03-01

    The article provides a tutorial review and trend assessment of the problem of alpha particle-induced soft errors in VLSI memories. Attention is given to an analysis of the design evolution of modern ICs, and the characteristics of alpha particles and their origin in IC packaging are reviewed. Finally, the process of an alpha particle penetrating an IC is examined.

  3. Microscopic histological characteristics of soft tissue sarcomas: analysis of tissue features and electrical resistance.

    PubMed

    Tosi, A L; Campana, L G; Dughiero, F; Forzan, M; Rastrelli, M; Sieni, E; Rossi, C R

    2017-07-01

    Tissue electrical conductivity is correlated with tissue characteristics. In this work, some soft tissue sarcomas (STS) excised from patients have been evaluated in terms of histological characteristics (cell size and density) and electrical resistance. The electrical resistance has been measured using the ex vivo study on soft tissue tumors electrical characteristics (ESTTE) protocol proposed by the authors in order to study electrical resistance of surgical samples excised by patients in a fixed measurement setup. The measurement setup includes a voltage pulse generator (700 V, 100 µs long at 5 kHz, period 200 µs) and an electrode with 7 needles, 20 mm-long, with the same distance arranged in a fixed hexagonal geometry. In the ESTTE protocol, the same voltage pulse sequence is applied to each different tumor mass and the corresponding resistance has been evaluated from voltage and current recorded by the equipment. For each tumor mass, a histological sample of the volume treated by means of voltage pulses has been taken for histological analysis. Each mass has been studied in order to identify the sarcoma type. For each histological sample, an image at 20× or 40× of magnification was acquired. In this work, the electrical resistance measured for each tumor has been correlated with tissue characteristics like the type, size and density of cells. This work presents a preliminary study to explore possible correlations between tissue characteristics and electrical resistance of STS. These results can be helpful to adjust the pulse voltage intensity in order to improve the electrochemotherapy efficacy on some histotype of STS.

  4. True Low-Power Self-Locking Soft Actuators.

    PubMed

    Kim, Seung Jae; Kim, Onnuri; Park, Moon Jeong

    2018-03-01

    Natural double-layered structures observed in living organisms are known to exhibit asymmetric volume changes with environmental triggers. Typical examples are natural roots of plants, which show unique self-organized bending behavior in response to environmental stimuli. Herein, light- and electro-active polymer (LEAP) based actuators with a double-layered structure are reported. The LEAP actuators exhibit an improvement of 250% in displacement and hold an object three times heavier as compared to that in the case of conventional electro-active polymer actuators. Most interestingly, the bending motion of the LEAP actuators can be effectively locked for a few tens of minutes even in the absence of a power supply. Further, the self-locking LEAP actuators show a large and reversible bending strain of more than 2.0% and require only 6.2 mW h cm -2 of energy to hold an object for 15 min at an operating voltage of 3 V. These novel self-locking soft actuators should find wide applicability in artificial muscles, biomedical microdevices, and various innovative soft robot technologies. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Development of crosslinked methylcellulose hydrogels for soft tissue augmentation using an ammonium persulfate-ascorbic acid redox system.

    PubMed

    Gold, Gittel T; Varma, Devika M; Taub, Peter J; Nicoll, Steven B

    2015-12-10

    Hydrogels composed of methylcellulose are candidate materials for soft tissue reconstruction. Although photocrosslinked methylcellulose hydrogels have shown promise for such applications, gels crosslinked using reduction-oxidation (redox) initiators may be more clinically viable. In this study, methylcellulose modified with functional methacrylate groups was polymerized using an ammonium persulfate (APS)-ascorbic acid (AA) redox initiation system to produce injectable hydrogels with tunable properties. By varying macromer concentration from 2% to 4% (w/v), the equilibrium moduli of the hydrogels ranged from 1.47 ± 0.33 to 5.31 ± 0.71 kPa, on par with human adipose tissue. Gelation time was found to conform to the ISO standard for injectable materials. Cellulase treatment resulted in complete degradation of the hydrogels within 24h, providing a reversible corrective feature. Co-culture with human dermal fibroblasts confirmed the cytocompatibility of the gels based on DNA measurements and Live/Dead imaging. Taken together, this evidence indicates that APS-AA redox-polymerized methylcellulose hydrogels possess properties beneficial for use as soft tissue fillers. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Injection initiated fracture in soft solids

    NASA Astrophysics Data System (ADS)

    Hutchens, Shelby; Yang, Steven

    Damage accumulation in soft materials under hydrostatic loading conditions is a primary injury mechanism in blast and blunt force trauma. A recently explored technique known as cavitation rheology (CR) provides a promising avenue for quickly and inexpensively approximating hydrostatic conditions via the reverse loading scenario, void pressurization. Past CR measurements of synthetic, polymeric materials at length scales from mm's to μm's have been found to correlate with both elastic modulus and fracture energy. The technique is performed via pressurization of fluid within a needle that is embedded within a material. This experimental setup allows crack evolution to be monitored, similar to traditional pre-notched failure samples. We observe a systematic evolution of crack morphology as a function of cross-link density in a soft elastomer. Crack shape is quantified using micro-computed tomography and shown to transition from being roughly penny-shaped to multi-lobed (predominately three) to spherical with decreasing crosslinking. Moduli are on the order of kPa. We describe this morphology evolution using a balance between the energetic costs of the strain energy in deforming the surrounding material and the intrinsic fracture energy necessary to form a new surface.

  7. Main braking phase for a soft moon landing as a form of trajectory correction

    NASA Astrophysics Data System (ADS)

    Likhachev, V. N.; Sikharulidze, Yu. G.; Fedotov, V. P.

    2013-12-01

    Rationale is given for the braking profile of a spacecraft making a soft landing on the Moon's surface, including the following four phases: main braking, free fall, repeated braking, and descent at a constant speed. Due to the large altitude differential over the braking path in near-polar regions of the Moon, main braking is proposed as a type of trajectory correction impulse using no altimeter. The boundary problem solution and statistical calculations are used to give the potential energy costs and characteristics of the dispersion characteristics for this phase and choose an optimal thrust-to-weight ratio for the phase.

  8. Nanoconfinement in activated mesoporous carbon of calcium borohydride for improved reversible hydrogen storage.

    PubMed

    Comănescu, Cezar; Capurso, Giovanni; Maddalena, Amedeo

    2012-09-28

    Mesoporous carbon frameworks were synthesized using the soft-template method. Ca(BH(4))(2) was incorporated into activated mesoporous carbon by the incipient wetness method. The activation of mesoporous carbon was necessary to optimize the surface area and pore size. Thermal programmed absorption measurements showed that the confinement of this borohydride into carbon nanoscaffolds improved its reversible capacity (relative to the reactive portion) and performance of hydrogen storage compared to unsupported borohydride. Hydrogen release from the supported hydride started at a temperature as low as 100 °C and the dehydrogenation rate was fast compared to the bulk borohydride. In addition, the hydrogen pressure necessary to regenerate the borohydride from the dehydrogenation products was reduced.

  9. 14 CFR 25.255 - Out-of-trim characteristics.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...-trim characteristics. (a) From an initial condition with the airplane trimmed at cruise speeds up to.../MFC and VDF/MDF the direction of the primary longitudinal control force may not reverse. (c) Except as... flight test with regard to reversal of primary longitudinal control force, flight tests must be...

  10. Melorheostosis mimicking synovial osteochondromatosis.

    PubMed

    Wadhwa, Vibhor; Chhabra, Avneesh; Samet, Jonathan D

    2014-01-01

    Melorheostosis is an uncommon, sporadic, sclerosing bone lesion that may affect the adjacent soft tissues. It has been associated with many entities such as osteopoikilosis, soft tissue vascular malformations, bone and soft tissue tumors, nephrotic syndrome, segmental limb contractures, osteosarcoma, desmoid tumor, and mesenteric fibromatosis. Synovial osteochondromatosis is a benign neoplasia of the hyaline cartilage presenting as nodules in the subsynovial tissue of a joint or tendon sheath. The intra-articular extension of melorheostosis mimicking synovial osteochondromatosis has not been reported before. In this article, the authors describe an unusual case mimicking synovial chondromatosis arising as a result of melorheostosis and their characteristic imaging findings.

  11. Multimodality management of soft tissue tumors in the extremity

    PubMed Central

    Crago, Aimee M.; Lee, Ann Y.

    2016-01-01

    Most extremity soft tissue sarcomas present as a painless mass. Workup should generally involve cross-sectional imaging with MRI, as well as a core biopsy for pathologic diagnosis. Limb-sparing surgery is the standard of care, and may be supplemented with radiation for histologic subtypes at higher risk for local recurrence and chemotherapy for those at higher risk for distant metastases. This article reviews the work-up and surgical approach to extremity soft tissue sarcomas, as well as the role for radiation and chemotherapy, with particular attention given to the distinguishing characteristics of some of the most common subtypes. PMID:27542637

  12. Flight Measurements of the Effect of a Controllable Thrust Reverser on the Flight Characteristics of a Single-Engine Jet Airplane

    NASA Technical Reports Server (NTRS)

    Anderson, Seth B.; Cooper, George E.; Faye, Alan E., Jr.

    1959-01-01

    A flight investigation was undertaken to determine the effect of a fully controllable thrust reverser on the flight characteristics of a single-engine jet airplane. Tests were made using a cylindrical target-type reverser actuated by a hydraulic cylinder through a "beep-type" cockpit control mounted at the base of the throttle. The thrust reverser was evaluated as an in-flight decelerating device, as a flight path control and airspeed control in landing approach, and as a braking device during the ground roll. Full deflection of the reverser for one reverser configuration resulted in a reverse thrust ratio of as much as 85 percent, which at maximum engine power corresponded to a reversed thrust of 5100 pounds. Use of the reverser in landing approach made possible a wide selection of approach angles, a large reduction in approach speed at steep approach angles, improved control of flight path angle, and more accuracy in hitting a given touchdown point. The use of the reverser as a speed brake at lower airspeeds was compromised by a longitudinal trim change. At the lower airspeeds and higher engine powers there was insufficient elevator power to overcome the nose-down trim change at full reverser deflection.

  13. Co-operation of digital nonlinear equalizers and soft-decision LDPC FEC in nonlinear transmission.

    PubMed

    Tanimura, Takahito; Oda, Shoichiro; Hoshida, Takeshi; Aoki, Yasuhiko; Tao, Zhenning; Rasmussen, Jens C

    2013-12-30

    We experimentally and numerically investigated the characteristics of 128 Gb/s dual polarization - quadrature phase shift keying signals received with two types of nonlinear equalizers (NLEs) followed by soft-decision (SD) low-density parity-check (LDPC) forward error correction (FEC). Successful co-operation among SD-FEC and NLEs over various nonlinear transmissions were demonstrated by optimization of parameters for NLEs.

  14. Manifestations of the MHD and kinetic dynamo through soft x-rays

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

    Chartas, G.A.

    1991-08-01

    The underlying mechanisms that produce and sustain the reversed toroidal field in RFP's are investigated by analyzing 2Dx-ray emissivity reconstruction and by correlating the evolution of the hot electron properties to the reversed toroidal magnetic field. Reconnection of emissivity surfaces as seen in soft x-ray (SXR) reconstructing occur near the predicted resonant surface for the m=1, n=5, 6,-7 resistive tearing modes. Two distinct rates of reversed magnetic field generation are observed. First, in the MHD relaxation phase a sudden increase in B{sub t}(a) is detected. This event coincides with a large increase in the edge hot electron current density. Themore » second mode of flux generation is observed t have a slower rate and occurs during the diffusion phase. A variation of the edge hot electron current density by a factor of four produced only a small change in the measured B{sub t}(a), implying the contributions of the hot electrons to the dynamo during the diffusion phase is small. {tilde T}{sub e}, / was measured to be approximately 60%, which is much larger than the corresponding quantity for the bulk component which is about 30%. Scaling of the magnetic Reynolds number with the diffusion and MHD relaxation time, {tau}{sub MHD} indicated that the {tau}{sub MHD} does not have a strong dependence on the Spitzer resistivity whereas the diffusion time does depend on the classical resistivity. SXR emission mode analysis during the transition from a rotating to a locked plasma shows a decrease in the m=1 Fourier Bastille component of the emissivity. This is due to the flattening of the emissivity profile as seen in the SXR reconstructions.« less

  15. Synthetically chemical-electrical mechanism for controlling large scale reversible deformation of liquid metal objects

    PubMed Central

    Zhang, Jie; Sheng, Lei; Liu, Jing

    2014-01-01

    Reversible deformation of a machine holds enormous promise across many scientific areas ranging from mechanical engineering to applied physics. So far, such capabilities are still hard to achieve through conventional rigid materials or depending mainly on elastomeric materials, which however own rather limited performances and require complicated manipulations. Here, we show a basic strategy which is fundamentally different from the existing ones to realize large scale reversible deformation through controlling the working materials via the synthetically chemical-electrical mechanism (SCHEME). Such activity incorporates an object of liquid metal gallium whose surface area could spread up to five times of its original size and vice versa under low energy consumption. Particularly, the alterable surface tension based on combination of chemical dissolution and electrochemical oxidation is ascribed to the reversible shape transformation, which works much more flexible than many former deformation principles through converting electrical energy into mechanical movement. A series of very unusual phenomena regarding the reversible configurational shifts are disclosed with dominant factors clarified. This study opens a generalized way to combine the liquid metal serving as shape-variable element with the SCHEME to compose functional soft machines, which implies huge potential for developing future smart robots to fulfill various complicated tasks. PMID:25408295

  16. A snail-eating snake recognizes prey handedness.

    PubMed

    Danaisawadi, Patchara; Asami, Takahiro; Ota, Hidetoshi; Sutcharit, Chirasak; Panha, Somsak

    2016-04-05

    Specialized predator-prey interactions can be a driving force for their coevolution. Southeast Asian snail-eating snakes (Pareas) have more teeth on the right mandible and specialize in predation on the clockwise-coiled (dextral) majority in shelled snails by soft-body extraction. Snails have countered the snakes' dextral-predation by recurrent coil reversal, which generates diverse counterclockwise-coiled (sinistral) prey where Pareas snakes live. However, whether the snake predator in turn evolves any response to prey reversal is unknown. We show that Pareas carinatus living with abundant sinistrals avoids approaching or striking at a sinistral that is more difficult and costly to handle than a dextral. Whenever it strikes, however, the snake succeeds in predation by handling dextral and sinistral prey in reverse. In contrast, P. iwasakii with little access to sinistrals on small peripheral islands attempts and frequently misses capturing a given sinistral. Prey-handedness recognition should be advantageous for right-handed snail-eating snakes where frequently encountering sinistrals. Under dextral-predation by Pareas snakes, adaptive fixation of a prey population for a reversal gene instantaneously generates a sinistral species because interchiral mating is rarely possible. The novel warning, instead of sheltering, effect of sinistrality benefitting both predators and prey could further accelerate single-gene ecological speciation by left-right reversal.

  17. Synthetically chemical-electrical mechanism for controlling large scale reversible deformation of liquid metal objects.

    PubMed

    Zhang, Jie; Sheng, Lei; Liu, Jing

    2014-11-19

    Reversible deformation of a machine holds enormous promise across many scientific areas ranging from mechanical engineering to applied physics. So far, such capabilities are still hard to achieve through conventional rigid materials or depending mainly on elastomeric materials, which however own rather limited performances and require complicated manipulations. Here, we show a basic strategy which is fundamentally different from the existing ones to realize large scale reversible deformation through controlling the working materials via the synthetically chemical-electrical mechanism (SCHEME). Such activity incorporates an object of liquid metal gallium whose surface area could spread up to five times of its original size and vice versa under low energy consumption. Particularly, the alterable surface tension based on combination of chemical dissolution and electrochemical oxidation is ascribed to the reversible shape transformation, which works much more flexible than many former deformation principles through converting electrical energy into mechanical movement. A series of very unusual phenomena regarding the reversible configurational shifts are disclosed with dominant factors clarified. This study opens a generalized way to combine the liquid metal serving as shape-variable element with the SCHEME to compose functional soft machines, which implies huge potential for developing future smart robots to fulfill various complicated tasks.

  18. Synthetically chemical-electrical mechanism for controlling large scale reversible deformation of liquid metal objects

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Sheng, Lei; Liu, Jing

    2014-11-01

    Reversible deformation of a machine holds enormous promise across many scientific areas ranging from mechanical engineering to applied physics. So far, such capabilities are still hard to achieve through conventional rigid materials or depending mainly on elastomeric materials, which however own rather limited performances and require complicated manipulations. Here, we show a basic strategy which is fundamentally different from the existing ones to realize large scale reversible deformation through controlling the working materials via the synthetically chemical-electrical mechanism (SCHEME). Such activity incorporates an object of liquid metal gallium whose surface area could spread up to five times of its original size and vice versa under low energy consumption. Particularly, the alterable surface tension based on combination of chemical dissolution and electrochemical oxidation is ascribed to the reversible shape transformation, which works much more flexible than many former deformation principles through converting electrical energy into mechanical movement. A series of very unusual phenomena regarding the reversible configurational shifts are disclosed with dominant factors clarified. This study opens a generalized way to combine the liquid metal serving as shape-variable element with the SCHEME to compose functional soft machines, which implies huge potential for developing future smart robots to fulfill various complicated tasks.

  19. "ALS reversals": demographics, disease characteristics, treatments, and co-morbidities.

    PubMed

    Harrison, Daniel; Mehta, Paul; van Es, Michael A; Stommel, Elijah; Drory, Vivian E; Nefussy, Beatrice; van den Berg, Leonard H; Crayle, Jesse; Bedlack, Richard

    2018-04-02

    To identify differences in demographics, disease characteristics, treatments, and co-morbidities between patients with "amyotrophic lateral sclerosis (ALS) reversals" and those with typically progressive ALS. Cases of possible ALS reversals were found in prior publications, in the Duke ALS clinic, through self-referral or referral from other Neurologists, and on the internet. Of 89 possible reversals identified, 36 cases were included because chart or literature review confirmed their diagnosis and a robust, sustained improvement in at least one objective measure. Controls were participants in the Pooled Resource Open-Access ALS Clinical Trials database and the National ALS Registry. Cases and controls were compared using descriptive statistics. ALS reversals were more likely to be male, have limb onset disease, and initially progress faster. The prevalences of myasthenia gravis (MG) and purely lower motor neuron disease in cases were higher than estimates of these prevalences in the general population. The odds of taking curcumin, luteolin, cannabidiol, azathioprine, copper, glutathione, vitamin D, and fish oil were greater for cases than controls. When compared to patients with typically progressive ALS, patients with reversals differed in their demographics, disease characteristics, and treatments. While some of these patients may have had a rare antibody-mediated ALS mimicker, such as atypical myasthenia gravis, details of their exams, EMGs and family histories argue that this was unlikely. Instead, our data suggest that ALS reversals warrant evaluation for mechanisms of disease resistance and that treatments associated with multiple ALS reversals deserve further study.

  20. Progress and Opportunities in Soft Photonics and Biologically Inspired Optics.

    PubMed

    Kolle, Mathias; Lee, Seungwoo

    2018-01-01

    Optical components made fully or partially from reconfigurable, stimuli-responsive, soft solids or fluids-collectively referred to as soft photonics-are poised to form the platform for tunable optical devices with unprecedented functionality and performance characteristics. Currently, however, soft solid and fluid material systems still represent an underutilized class of materials in the optical engineers' toolbox. This is in part due to challenges in fabrication, integration, and structural control on the nano- and microscale associated with the application of soft components in optics. These challenges might be addressed with the help of a resourceful ally: nature. Organisms from many different phyla have evolved an impressive arsenal of light manipulation strategies that rely on the ability to generate and dynamically reconfigure hierarchically structured, complex optical material designs, often involving soft or fluid components. A comprehensive understanding of design concepts, structure formation principles, material integration, and control mechanisms employed in biological photonic systems will allow this study to challenge current paradigms in optical technology. This review provides an overview of recent developments in the fields of soft photonics and biologically inspired optics, emphasizes the ties between the two fields, and outlines future opportunities that result from advancements in soft and bioinspired photonics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Magnetic Resonance Imaging With Cochlear Implant Magnet in Place: Safety and Imaging Quality.

    PubMed

    Carlson, Matthew L; Neff, Brian A; Link, Michael J; Lane, John I; Watson, Robert E; McGee, Kiaran P; Bernstein, Matt A; Driscoll, Colin L W

    2015-07-01

    To evaluate the safety and image quality of 1.5-T MRI in patients with cochlear implants and retained internal magnets. Retrospective case series from 2012 to 2014. Single tertiary academic referral center. All cochlear implant recipients undergoing 1.5-T MRI without internal magnet removal. MRI after tight headwrap application. Patient tolerance, complications, and characteristics of imaging artifact. Nineteen ears underwent a total of 34 MRI scans. Two patients did not tolerate imaging with the headwrap in place and required magnet removal before rescanning. One subject experienced two separate episodes of polarity reversal in the same device from physical realignment (i.e., flipping) of the internal magnet requiring surgical repositioning. Three patients were discovered to have canting of the internal magnet after imaging. In all three cases, the magnet could be reseated by applying gentle firm pressure to the scalp until the magnet "popped" back into place. These patients continue to use their device without difficulty and have not required surgical replacement. In patients receiving head MRI, the ipsilateral internal auditory canal and cerebellopontine angle could be visualized without difficulty in 94% of cases. There were no episodes of cochlear implant device failure or soft tissue complications. Under controlled conditions, 1.5-T MRI can be successfully performed in most patients without the need for cochlear implant magnet removal. In nearly all cases, imaging artifact does not impede evaluation of the ipsilateral skull base. Patients should be counseled regarding the risk of internal magnet movement that may occur in up to 15% of cases, even with tight headwrap application. If internal magnet polarity reversal occurs, a trial of reversing the external magnet can be considered. If canting or mild displacement of the internal magnet occurs, an attempt at reseating can be made by applying gentle firm pressure to the scalp over the internal magnet. If conservative measures fail, the magnet should be surgically repositioned to minimize interruption of device use and to prevent scalp complications.

  2. Aeroelastic considerations for torsionally soft rotors

    NASA Technical Reports Server (NTRS)

    Mantay, W. R.; Yeager, W. T., Jr.

    1985-01-01

    A research study was initiated to systematically determine the impact of selected blade tip geometric parameters on conformable rotor performance and loads characteristics. The model articulated rotors included baseline and torsionally soft blades with interchangeable tips. Seven blade tip designs were evaluated on the baseline rotor and six tip designs were tested on the torsionally soft blades. The designs incorporated a systemmatic variation in geometric parameters including sweep, taper, and anhedral. The rotors were evaluated in the NASA Langley Transonic Dynamics Tunnel at several advance ratios, lift and propulsive force values, and tip Mach numbers. A track sensitivity study was also conducted at several advance ratios for both rotors. Based on the test results, tip parameter variations generated significant rotor performance and loads differences for both baseline and torsionally soft blades.

  3. High-grade extremity soft tissue sarcomas: factors predictive of local recurrence and its effect on morbidity and mortality.

    PubMed

    Eilber, Fritz C; Rosen, Gerald; Nelson, Scott D; Selch, Michael; Dorey, Frederick; Eckardt, Jeffery; Eilber, Frederick R

    2003-02-01

    To identify patient characteristics associated with the development of local recurrence and the effect of local recurrence on subsequent morbidity and mortality in patients with intermediate- to high-grade extremity soft tissue sarcomas. Numerous studies on extremity soft tissue sarcomas have consistently shown that presentation with locally recurrent disease is associated with the development of subsequent local recurrences and that large tumor size and high histologic grade are significant factors associated with decreased survival. However, the effect of local recurrence on patient survival remains unclear. From 1975 to 1997, 753 patients with intermediate- to high-grade extremity soft tissue sarcomas were treated at UCLA. Treatment outcomes and patient characteristics were analyzed to identify factors associated with both local recurrence and survival. Patients with locally recurrent disease were at a significantly increased risk of developing a subsequent local recurrence. Local recurrence was a morbid event requiring amputation in 38% of the cases. The development of a local recurrence was the most significant factor associated with decreased survival. Once a patient developed a local recurrence, he or she was about three times more likely to die of disease compared to similar patients who had not developed a local recurrence. Local recurrence in patients with intermediate- to high-grade extremity soft tissue sarcomas is associated with the development of subsequent local recurrences, a morbid event decreasing functional outcomes and the most significant factor associated with decreased survival. Although 85% to 90% of patients with high-grade extremity soft tissue sarcomas are treatable with a limb salvage approach, patients who develop a local recurrence need aggressive treatment and should be considered for trials of adjuvant systemic therapy.

  4. What are the characteristics of breast cancers misclassified as benign by quantitative ultrasound shear wave elastography?

    PubMed

    Vinnicombe, S J; Whelehan, P; Thomson, K; McLean, D; Purdie, C A; Jordan, L B; Hubbard, S; Evans, A J

    2014-04-01

    Shear wave elastography (SWE) is a promising adjunct to greyscale ultrasound in differentiating benign from malignant breast masses. The purpose of this study was to characterise breast cancers which are not stiff on quantitative SWE, to elucidate potential sources of error in clinical application of SWE to evaluation of breast masses. Three hundred and two consecutive patients examined by SWE who underwent immediate surgery for breast cancer were included. Characteristics of 280 lesions with suspicious SWE values (mean stiffness >50 kPa) were compared with 22 lesions with benign SWE values (<50 kPa). Statistical significance of the differences was assessed using non-parametric goodness-of-fit tests. Pure ductal carcinoma in situ (DCIS) masses were more often soft on SWE than masses representing invasive breast cancer. Invasive cancers that were soft were more frequently: histological grade 1, tubular subtype, ≤10 mm invasive size and detected at screening mammography. No significant differences were found with respect to the presence of invasive lobular cancer, vascular invasion, hormone and HER-2 receptor status. Lymph node positivity was less common in soft cancers. Malignant breast masses classified as benign by quantitative SWE tend to have better prognostic features than those correctly classified as malignant. • Over 90 % of cancers assessable with ultrasound have a mean stiffness >50 kPa. • 'Soft' invasive cancers are frequently small (≤10 mm), low grade and screen-detected. • Pure DCIS masses are more often soft than invasive cancers (>40 %). • Large symptomatic masses are better evaluated with SWE than small clinically occult lesions. • When assessing small lesions, 'softness' should not raise the threshold for biopsy.

  5. Drusen Characterization with Multimodal Imaging

    PubMed Central

    Spaide, Richard F.; Curcio, Christine A.

    2010-01-01

    Summary Multimodal imaging findings and histological demonstration of soft drusen, cuticular drusen, and subretinal drusenoid deposits provided information used to develop a model explaining their imaging characteristics. Purpose To characterize the known appearance of cuticular drusen, subretinal drusenoid deposits (reticular pseudodrusen), and soft drusen as revealed by multimodal fundus imaging; to create an explanatory model that accounts for these observations. Methods Reported color, fluorescein angiographic, autofluorescence, and spectral domain optical coherence tomography (SD-OCT) images of patients with cuticular drusen, soft drusen, and subretinal drusenoid deposits were reviewed, as were actual images from affected eyes. Representative histological sections were examined. The geometry, location, and imaging characteristics of these lesions were evaluated. A hypothesis based on the Beer-Lambert Law of light absorption was generated to fit these observations. Results Cuticular drusen appear as numerous uniform round yellow-white punctate accumulations under the retinal pigment epithelium (RPE). Soft drusen are larger yellow-white dome-shaped mounds of deposit under the RPE. Subretinal drusenoid deposits are polymorphous light-grey interconnected accumulations above the RPE. Based on the model, both cuticular and soft drusen appear yellow due to the removal of shorter wavelength light by a double pass through the RPE. Subretinal drusenoid deposits, which are located on the RPE, are not subjected to short wavelength attenuation and therefore are more prominent when viewed with blue light. The location and morphology of extracellular material in relationship to the RPE, and associated changes to RPE morphology and pigmentation, appeared to be primary determinants of druse appearance in different imaging modalities. Conclusion Although cuticular drusen, subretinal drusenoid deposits, and soft drusen are composed of common components, they are distinguishable by multimodal imaging due to differences in location, morphology, and optical filtering effects by drusenoid material and the RPE. PMID:20924263

  6. Precursor directed synthesis - ``molecular'' mechanisms in the Soft Chemistry approaches and their use for template-free synthesis of metal, metal oxide and metal chalcogenide nanoparticles and nanostructures

    NASA Astrophysics Data System (ADS)

    Seisenbaeva, Gulaim A.; Kessler, Vadim G.

    2014-05-01

    This review provides an insight into the common reaction mechanisms in Soft Chemistry processes involved in nucleation, growth and aggregation of metal, metal oxide and chalcogenide nanoparticles starting from metal-organic precursors such as metal alkoxides, beta-diketonates, carboxylates and their chalcogene analogues and demonstrates how mastering the precursor chemistry permits us to control the chemical and phase composition, crystallinity, morphology, porosity and surface characteristics of produced nanomaterials.This review provides an insight into the common reaction mechanisms in Soft Chemistry processes involved in nucleation, growth and aggregation of metal, metal oxide and chalcogenide nanoparticles starting from metal-organic precursors such as metal alkoxides, beta-diketonates, carboxylates and their chalcogene analogues and demonstrates how mastering the precursor chemistry permits us to control the chemical and phase composition, crystallinity, morphology, porosity and surface characteristics of produced nanomaterials. To Professor David Avnir on his 65th birthday.

  7. Image processing can cause some malignant soft-tissue lesions to be missed in digital mammography images.

    PubMed

    Warren, L M; Halling-Brown, M D; Looney, P T; Dance, D R; Wallis, M G; Given-Wilson, R M; Wilkinson, L; McAvinchey, R; Young, K C

    2017-09-01

    To investigate the effect of image processing on cancer detection in mammography. An observer study was performed using 349 digital mammography images of women with normal breasts, calcification clusters, or soft-tissue lesions including 191 subtle cancers. Images underwent two types of processing: FlavourA (standard) and FlavourB (added enhancement). Six observers located features in the breast they suspected to be cancerous (4,188 observations). Data were analysed using jackknife alternative free-response receiver operating characteristic (JAFROC) analysis. Characteristics of the cancers detected with each image processing type were investigated. For calcifications, the JAFROC figure of merit (FOM) was equal to 0.86 for both types of image processing. For soft-tissue lesions, the JAFROC FOM were better for FlavourA (0.81) than FlavourB (0.78); this difference was significant (p=0.001). Using FlavourA a greater number of cancers of all grades and sizes were detected than with FlavourB. FlavourA improved soft-tissue lesion detection in denser breasts (p=0.04 when volumetric density was over 7.5%) CONCLUSIONS: The detection of malignant soft-tissue lesions (which were primarily invasive) was significantly better with FlavourA than FlavourB image processing. This is despite FlavourB having a higher contrast appearance often preferred by radiologists. It is important that clinical choice of image processing is based on objective measures. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  8. Characteristics and engineering properties of the soft soil layer in highway soil subgrades.

    DOT National Transportation Integrated Search

    2006-06-01

    The objective of this research was to examine the conditions and characteristics of soil subgrades that had been stabilized using mechanical compaction. Goals of the study are to identify and examine the engineering properties and behavior of the ...

  9. Temporal Modulation of Stem Cell Activity Using Magnetoactive Hydrogels.

    PubMed

    Abdeen, Amr A; Lee, Junmin; Bharadwaj, N Ashwin; Ewoldt, Randy H; Kilian, Kristopher A

    2016-10-01

    Cell activity is coordinated by dynamic interactions with the extracellular matrix, often through stimuli-mediated spatiotemporal stiffening and softening. Dynamic changes in mechanics occur in vivo through enzymatic or chemical means, processes which are challenging to reconstruct in cell culture materials. Here a magnetoactive hydrogel material formed by embedding magnetic particles in a hydrogel matrix is presented whereby elasticity can be modulated reversibly by attenuation of a magnetic field. Orders of magnitude change in elasticity using low magnetic fields are shown and reversibility of stiffening with simple permanent magnets is demonstrated. The broad applicability of this technique is demonstrated with two therapeutically relevant bioactivities in mesenchymal stem cells: secretion of proangiogenic molecules, and dynamic control of osteogenesis. The ability to reversibly stiffen cell culture materials across the full spectrum of soft tissue mechanics, using simple materials and commercially available permanent magnets, makes this approach viable for a broad range of laboratory environments. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Magnetization reversal mechanism of magnetic tunnel junctions

    NASA Astrophysics Data System (ADS)

    Liu, Cun-Ye; Li, Jian; Wang, Yue; Chen, Jian-Yong; Xu, Qing-Yu; Ni, Gang; Sang, Hai; Du, You-Wei

    2002-01-01

    Using the ion-beam-sputtering technique, we have fabricated Fe/Al2O3/Fe magnetic tunnelling junctions (MTJs). We have observed double-peaked shapes of curves, which have a level summit and a symmetrical feature, showing the magnetoresistance of the junction as a function of applied field. We have measured the tunnel conductance of MTJs which have insulating layers of different thicknesses. We have studied the dependence of the magnetoresistance of MTJs on tunnel conductance. The microstructures of hard- and soft-magnetic layers and interfaces of ferromagnets and insulators were probed. Analysing the influence of MJT microstructures, including those having clusters or/and granules in magnetic and non-magnetic films, a magnetization reversal mechanism (MRM) is proposed, which suggests that the MRM of tunnelling junctions may be explained by using a group-by-group reversal model of magnetic moments of the mesoscopical particles. We discuss the influence of MTJ microstructures, including those with clusters or/and granules in the ferromagnetic and non-magnetic films, on the MRM.

  11. Supercooling of water confined in reverse micelles

    NASA Astrophysics Data System (ADS)

    Spehr, T.; Frick, B.; Grillo, I.; Stühn, B.

    2008-03-01

    We report on the temperature dependence of the nanosecond-timescale dynamics of the ternary mixture water/AOT/oil with deuterated heptane, toluene or decane as the oil. Water-swollen reverse micelles as formed in such microemulsions allow us to investigate the freezing behaviour of water confined in a soft environment. We report here on the first neutron scattering studies in which the freezing of the confined water and of the oil is followed down to temperatures at which the whole system is frozen. We focus on studies of water confined in three different droplet sizes: by means of small-angle neutron scattering we have determined the radii to be 46, 18, and 7 Å for water to surfactant ratios ω = 40, 12, and 3. From elastic temperature scans by neutron backscattering we deduce a strong supercooling of water confined in the reverse swollen micelles which increases with decreasing droplet size. For the smallest droplets we find a supercooling of more than 45 K compared to bulk water.

  12. Giant actuation strain nearly 0.6% in a periodically orthogonal poled lead titanate zirconate ceramic via reversible domain switching

    NASA Astrophysics Data System (ADS)

    Li, Faxin; Wang, Qiangzhong; Miao, Hongchen

    2017-08-01

    The widely used ferroelectric ceramics based actuators always suffer from small output strains (typically ˜0.1%-0.15%). Non-180° domain switching can generate a large strain in ferroelectrics but it is usually irreversible. In this work, we tailored the domain structures in a soft lead titanate zirconate (PZT) ceramic by periodical orthogonal poling. The non-180° switching in this domain-engineered PZT ceramics turns to be reversible, resulting in a local giant actuation strain of nearly 0.6% under a field of 2 kV/mm at 0.1 Hz. The large interfacial stresses between regions with different poling directions during electric loading/unloading were thought to be responsible for the reversible non-180° domain switching. The switching strain drops quickly with the increasing frequency, and stabilized at about 0.2% at or above 1.0 Hz. The large actuation strain remains quite stable after 104 cycles of loading, which is very promising for low-frequency, large-strain actuators.

  13. Constructing hierarchical submicrotubes from interconnected TiO2 nanocrystals for high reversible capacity and long-life lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Xin, Ling; Liu, Yong; Li, Baojun; Zhou, Xiang; Shen, Hui; Zhao, Wenxia; Liang, Chaolun

    2014-03-01

    Here, we report a facile hydrothermal approach for synthesizing anatase TiO2 hierarchical mesoporous submicrotubes (ATHMSs) with the aid of long-chain polymer as soft template. The TiO2 nanocrystals, with sizes of 6-8 nm, are well interconnected with each other to build tubular architectures with diameters of 0.3-1.5 μm and lengths of 10-25 μm. Such highly porous structures give rise to very large specific surface area of 201.9 m2 g-1 and 136.8 m2 g-1 for the as-prepared and annealed samples, respectively. By using structurally stable ATHMSs as anode materials for lithium-ion batteries, they exhibited high reversible capacity, long cycling life and excellent cycling stability. Even after 1000 cycles, such ATHMS electrodes retained a reversible discharge capacity as high as 150 mAh g-1 at the current density of 1700 mA g-1, maintaining 92% of the initial discharge capacity (163 mAh g-1).

  14. Modelling reverse characteristics of power LEDs with thermal phenomena taken into account

    NASA Astrophysics Data System (ADS)

    Ptak, Przemysław; Górecki, Krzysztof

    2016-01-01

    This paper refers to modelling characteristics of power LEDs with a particular reference to thermal phenomena. Special attention is paid to modelling characteristics of the circuit protecting the considered device against the excessive value of the reverse voltage and to the description of the temperature influence on optical power. The network form of the worked out model is presented and some results of experimental verification of this model for the selected diodes operating at different cooling conditions are described. The very good agreement between the calculated and measured characteristics is obtained.

  15. "The phactalysts": carbon nanotube/TiO2 composites as phototropic actuators for wireless remote triggering of chemical reactions and catalysis.

    PubMed

    Vassalini, Irene; Alessandri, Ivano

    2017-08-17

    A new concept of a reconfigurable smart catalyst was developed from the synergistic combination of polycarbonate/carbon nanotube bimorph photoactuators and TiO 2 . The addition of TiO 2 provides the photoactuators with photocatalytic activity and superior opto-mechanical properties, making phototropic actuation fast, reversible and responsive to Vis-NIR light sources. These composites were tested in the wireless, light-driven and spatially controlled remote triggering of different chemical reactions, including local explosions and photocatalytic polymerizations. The same materials were also investigated as efficient opto-mechanical shutters for the light-selective inhibition or activation of specific reactions, such as the photo-induced degradation of organic dyes. These results suggest that the integration of photocatalysts with soft photoactuators can open intriguing opportunities for chemistry and soft robotics.

  16. Tunable smart digital structure (SDS) to modularly assemble soft actuators with layered adhesive bonding

    NASA Astrophysics Data System (ADS)

    Jin, Hu; Dong, Erbao; Xu, Min; Xia, Qirong; Liu, Shuai; Li, Weihua; Yang, Jie

    2018-01-01

    Many shape memory alloy (SMA)-based soft actuators have specific composite structures and manufacture processes, and are therefore unique. However, these exclusive characteristics limit their capabilities and applications, so in this article a soft and smart digital structure (SDS) is proposed that acts like a modular unit to assemble soft actuators by a layered adhesive bonding process. The SDS is a fully soft structure that encapsulates a digital skeleton consisting of four groups of parallel and independently actuated SMA wires capable of outputting a four-channel tunable force. The layered adhesive bonding process modularly bonds several SDSs with an elastic backbone to fabricate a layered soft actuator where the elastic backbone is used to recover the SDSs in a cooling process using the SMA wires. Two kinds of SDS-based soft actuators were modularly assembled, an actuator, SDS-I, with a two-dimensional reciprocal motion, and an actuator, SDS-II, capable of bi-directional reciprocal motion. The thermodynamics and phase transformation modeling of the SDS-based actuator were analyzed. Several extensional soft actuators were also assembled by bonding the SDS with an anomalous elastic backbone or modularly assembling the SDS-Is and SDS-IIs. These modularly assembled soft actuators delivered more output channels and a complicated motion, e.g., an actinomorphic soft actuator with four SDS-Is jumps in a series of hierarchical heights and directional movement by tuning the input channels of the SDSs. This result showed that the SDS can modularly assemble multifarious soft actuators with diverse capabilities, steerability and tunable outputs.

  17. Use of methylnaltrexone to induce laxation in acutely injured patients with burns and necrotizing soft-tissue infections.

    PubMed

    Hewitt, Kelly; Lin, Hsin; Faraklas, Iris; Morris, Stephen; Cochran, Amalia; Saffle, Jeffrey

    2014-01-01

    The routine use of high-dose opioids for analgesia in patients with acute burns and soft-tissue injuries often leads to the development of opioid-induced constipation. The opioid antagonist methylnaltrexone (MLTX) reverses narcotic-related ileus without affecting systemic pain treatment. The authors' burn center developed a bowel protocol that included administration of MLTX for relief of opioid-induced constipation after other methods failed. The authors performed a retrospective review of patients with acute burns or necrotizing soft-tissue infections, who had been given subcutaneous MLTX to induce laxation. All patients who received MLTX were included and all administrations of the drug were included in the analysis. The primary outcome examined was time to laxation from drug administration. Forty-eight patients received MLTX a total of 112 times. Six patients were admitted with soft-tissue injuries and the rest suffered burns with an average TBSA of 17%. The median patient age was 41 years and the majority (75%) were men. Administration of a single dose of MLTX resulted in laxation within 4 hours in 38% of cases, and within 24 hours in 68%. Patients given MLTX received an average of 174 mg morphine equivalents daily for pain control. MLTX was given after an average of 52 hours since the last bowel movement. As this experience has evolved, it has been incorporated into an organized bowel protocol, which includes MLTX administration after other laxatives have failed. MLTX is an effective laxation agent in patients with burn and soft-tissue injuries, who have failed conventional agents.

  18. Unique Features of Halophilic Proteins.

    PubMed

    Arakawa, Tsutomu; Yamaguchi, Rui; Tokunaga, Hiroko; Tokunaga, Masao

    2017-01-01

    Proteins from moderate and extreme halophiles have unique characteristics. They are highly acidic and hydrophilic, similar to intrinsically disordered proteins. These characteristics make the halophilic proteins soluble in water and fold reversibly. In addition to reversible folding, the rate of refolding of halophilic proteins from denatured structure is generally slow, often taking several days, for example, for extremely halophilic proteins. This slow folding rate makes the halophilic proteins a novel model system for folding mechanism analysis. High solubility and reversible folding also make the halophilic proteins excellent fusion partners for soluble expression of recombinant proteins.

  19. Effect of Photogenerated Carriers on Ferroelectric Polarization Reversal

    NASA Astrophysics Data System (ADS)

    Weis, Martin; Li, Jun; Taguchi, Dai; Manaka, Takaaki; Iwamoto, Mitsumasa

    2011-12-01

    Three non-symmetric switching peaks were observed in current-voltage (J-V) characteristic of the pentacene/poly(vinylidene fluoride-trifluoroethylene) double-layer device. However, upon illumination only two symmetric switching peaks appeared during the same J-V measurement. The similar difference between dark and illumination were also obtained in capacitance-voltage characteristics. These results showed the strong influence of internal fields by photogenerated carriers, which modifies the polarization reversal process of ferroelectric layer. The gradual shift of the polarization reversal with increase of illumination intensity is assigned to the space-charge field of trapped electrons.

  20. High frequency, high temperature specific core loss and dynamic B-H hysteresis loop characteristics of soft magnetic alloys

    NASA Technical Reports Server (NTRS)

    Wieserman, W. R.; Schwarze, G. E.; Niedra, J. M.

    1990-01-01

    Limited experimental data exists for the specific core loss and dynamic B-H loops for soft magnetic materials for the combined conditions of high frequency and high temperature. This experimental study investigates the specific core loss and dynamic B-H loop characteristics of Supermalloy and Metglas 2605SC over the frequency range of 1 to 50 kHz and temperature range of 23 to 300 C under sinusoidal voltage excitation. The experimental setup used to conduct the investigation is described. The effects of the maximum magnetic flux density, frequency, and temperature on the specific core loss and on the size and shape of the B-H loops are examined.

  1. Reproducibility of the pink esthetic score--rating soft tissue esthetics around single-implant restorations with regard to dental observer specialization.

    PubMed

    Gehrke, Peter; Lobert, Markus; Dhom, Günter

    2008-01-01

    The pink esthetic score (PES) evaluates the esthetic outcome of soft tissue around implant-supported single crowns in the anterior zone by awarding seven points for the mesial and distal papilla, soft-tissue level, soft-tissue contour, soft-tissue color, soft-tissue texture, and alveolar process deficiency. The aim of this study was to measure the reproducibility of the PES and assess the influence exerted by the examiner's degree of dental specialization. Fifteen examiners (three general dentists, three oral maxillofacial surgeons, three orthodontists, three postgraduate students in implant dentistry, and three lay people) applied the PES to 30 implant-supported single restorations twice at an interval of 4 weeks. Using a 0-1-2 scoring system, 0 being the lowest, 2 being the highest value, the maximum achievable PES was 14. At the second assessment, the photographs were scored in reverse order. Differences between the two assessments were evaluated with the Spearman's rank correlation coefficient (R). The Wilcoxon signed-rank test was used for comparisons of differences between the ratings. A significance level of p < 0.05 was chosen for both tests. Observer results indicated that the agreement between the first and second rating for all occupational groups was 70.5%, with a broad correlation between the two ratings and a high statistical significance (Spearman's R = 0.58, p = 0; Wilcoxon T = 163,182, Z = 3.383599, p = 0.000716). The most agreement between the first and second rating was obtained by orthodontists with 73.5% (R = 0.67), and the least by lay people 65.9% (R = 0.50). Very poor and very esthetic restorations showed the smallest deviations. Orthodontists were found to have assigned significantly poorer ratings than any other group. The assessment of postgraduate students and laypersons were the most favorable. The PES allows for a more objective appraisal of the esthetic short- and long-term results of various surgical and prosthetic implant procedures. It reproducibly evaluates the peri-implant soft tissue around single-implant restorations and results in good intra-examiner agreement. However, an effect of observer specialization on rating soft-tissue esthetics can be shown.

  2. A supplemented soft agar chemotaxis assay demonstrates the Helicobacter pylori chemotactic response to zinc and nickel

    PubMed Central

    Sanders, Lisa; Andermann, Tessa M.

    2013-01-01

    Directed motility, or chemotaxis, is required for Helicobacter pylori to establish infection in the stomach, although the full repertoire of this bacterium’s chemotactic responses is not yet known. Here we report that H. pylori responds to zinc as an attractant and nickel as a repellent. To reach this conclusion, we employed both a temporal chemotaxis assay based on bacterial reversals and a supplemented soft agar spatial assay. We refined the temporal assay using a previously described chemorepellent, acid, and found that H. pylori requires rich media with serum to maintain optimal swimming motility. Surprisingly, we found that some strains respond to acid as an attractant, and that the TlpC chemoreceptor correlated with whether acid was sensed as an attractant or repellent. Using this same assay, we detected weak repellent responses to nickel and copper, and a varied response to zinc. We thus developed an alternative spatial chemotactic assay called the supplemented soft agar assay, which utilizes soft agar medium supplemented with the test compound. With Escherichia coli, the attractant serine slowed overall bacterial migration, while the repellent nickel increased the speed of overall migration. In H. pylori we detected slowed migration with doubled tryptone media, as well as zinc, consistent with an attractant response. In contrast, nickel increased migration, consistent with repulsion. PMID:23139399

  3. Reverse Transfer Student Characteristics--Fall 1979. Office of Institutional Research, Research Report 80-3.

    ERIC Educational Resources Information Center

    Drakulich, J. Scott; Karlen, Janice M.

    In order to determine the characteristics of students who transferred to Essex County College from four-year institutions in Fall 1979, the responses of 88 reverse transfer students (RTS's) to 84 items on the entering student demographic questionnaire were compared to the responses of 2,087 new Fall 1979 students. The questionnaire solicited…

  4. Design and Performance of a Pinned Photodiode CMOS Image Sensor Using Reverse Substrate Bias.

    PubMed

    Stefanov, Konstantin D; Clarke, Andrew S; Ivory, James; Holland, Andrew D

    2018-01-03

    A new pinned photodiode (PPD) CMOS image sensor with reverse biased p-type substrate has been developed and characterized. The sensor uses traditional PPDs with one additional deep implantation step to suppress the parasitic reverse currents, and can be fully depleted. The first prototypes have been manufactured on an 18 µm thick, 1000 Ω·cm epitaxial silicon wafers using 180 nm PPD image sensor process. Both front-side illuminated (FSI) and back-side illuminated (BSI) devices were manufactured in collaboration with Teledyne e2v. The characterization results from a number of arrays of 10 µm and 5.4 µm PPD pixels, with different shape, the size and the depth of the new implant are in good agreement with device simulations. The new pixels could be reverse-biased without parasitic leakage currents well beyond full depletion, and demonstrate nearly identical optical response to the reference non-modified pixels. The observed excessive charge sharing in some pixel variants is shown to not be a limiting factor in operation. This development promises to realize monolithic PPD CIS with large depleted thickness and correspondingly high quantum efficiency at near-infrared and soft X-ray wavelengths.

  5. Design and Performance of a Pinned Photodiode CMOS Image Sensor Using Reverse Substrate Bias †

    PubMed Central

    Clarke, Andrew S.; Ivory, James; Holland, Andrew D.

    2018-01-01

    A new pinned photodiode (PPD) CMOS image sensor with reverse biased p-type substrate has been developed and characterized. The sensor uses traditional PPDs with one additional deep implantation step to suppress the parasitic reverse currents, and can be fully depleted. The first prototypes have been manufactured on an 18 µm thick, 1000 Ω·cm epitaxial silicon wafers using 180 nm PPD image sensor process. Both front-side illuminated (FSI) and back-side illuminated (BSI) devices were manufactured in collaboration with Teledyne e2v. The characterization results from a number of arrays of 10 µm and 5.4 µm PPD pixels, with different shape, the size and the depth of the new implant are in good agreement with device simulations. The new pixels could be reverse-biased without parasitic leakage currents well beyond full depletion, and demonstrate nearly identical optical response to the reference non-modified pixels. The observed excessive charge sharing in some pixel variants is shown to not be a limiting factor in operation. This development promises to realize monolithic PPD CIS with large depleted thickness and correspondingly high quantum efficiency at near-infrared and soft X-ray wavelengths. PMID:29301379

  6. Simultaneous determination of ascorbic acid and caffeine in commercial soft drinks using reversed-phase ultraperformance liquid chromatography.

    PubMed

    Turak, Fatma; Güzel, Remziye; Dinç, Erdal

    2017-04-01

    A new reversed-phase ultraperformance liquid chromatography method with a photodiode array detector was developed for the quantification of ascorbic acid (AA) and caffeine (CAF) in 11 different commercial drinks consisting of one energy drink and 10 ice tea drinks. Separation of the analyzed AA and CAF with an internal standard, caffeic acid, was performed on a Waters BEH C 18 column (100 mm × 2.1 mm, 1.7 μm i.d.), using a mobile phase consisting of acetonitrile and 0.2M H 3 PO 4 (11:89, v/v) with a flow rate of 0.25 mL/min and an injection volume of 1.0 μL. Calibration graphs for AA and CAF were computed from the peak area ratio of AA/internal standard and CAF/internal standard detected at 244.0 nm and 273.6 nm, respectively. The developed reversed-phase ultraperformance liquid chromatography method was validated by analyzing standard addition samples. The proposed reversed-phase ultraperformance liquid chromatography method gave us successful results for the quantitative analysis of commercial drinks containing AA and CAF substances. Copyright © 2016. Published by Elsevier B.V.

  7. Magnetization processes in core/shell exchange-spring structures.

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

    Jiang, J. S.

    2015-03-27

    The magnetization reversal processes in cylindrical and spherical soft core/hard shell exchange-spring structures are investigated via the analytical nucleation theory, and are verified with numerical micromagnetic simulations. At small core sizes, the nucleation of magnetic reversal proceeds via the modified bulging mode, where the transverse component of the magnetization is only semi-coherent in direction and the nucleation field contains a contribution from self-demagnetization. For large core sizes, the modified curling mode, where the magnetization configuration is vortex-like, is favored at nucleation. The preference for the modified curling mode is beneficial in that the fluxclosure allows cylindrical and spherical core/shell exchange-springmore » elements to be densely packed into bulk permanent magnets without affecting the nucleation field, thereby offering the potential for high energy product.« less

  8. On the soft supersymmetry-breaking parameters in gauge-mediated models

    NASA Astrophysics Data System (ADS)

    Wagner, C. E. M.

    1998-09-01

    Gauge mediation of supersymmetry breaking in the observable sector is an attractive idea, which naturally alleviates the flavor changing neutral current problem of supersymmetric theories. Quite generally, however, the number and quantum number of the messengers are not known; nor is their characteristic mass scale determined by the theory. Using the recently proposed method to extract supersymmetry-breaking parameters from wave-function renormalization, we derived general formulae for the soft supersymmetry-breaking parameters in the observable sector, valid in the small and moderate tan β regimes, for the case of split messengers. The full leading-order effects of top Yukawa and gauge couplings on the soft supersymmetry-breaking parameters are included. We give a simple interpretation of the general formulae in terms of the renormalization group evolution of the soft supersymmetry-breaking parameters. As a by-product of this analysis, the one-loop renormalization group evolution of the soft supersymmetry-breaking parameters is obtained for arbitrary boundary conditions of the scalar and gaugino mass parameters at high energies.

  9. Novel Blind Recognition Algorithm of Frame Synchronization Words Based on Soft-Decision in Digital Communication Systems.

    PubMed

    Qin, Jiangyi; Huang, Zhiping; Liu, Chunwu; Su, Shaojing; Zhou, Jing

    2015-01-01

    A novel blind recognition algorithm of frame synchronization words is proposed to recognize the frame synchronization words parameters in digital communication systems. In this paper, a blind recognition method of frame synchronization words based on the hard-decision is deduced in detail. And the standards of parameter recognition are given. Comparing with the blind recognition based on the hard-decision, utilizing the soft-decision can improve the accuracy of blind recognition. Therefore, combining with the characteristics of Quadrature Phase Shift Keying (QPSK) signal, an improved blind recognition algorithm based on the soft-decision is proposed. Meanwhile, the improved algorithm can be extended to other signal modulation forms. Then, the complete blind recognition steps of the hard-decision algorithm and the soft-decision algorithm are given in detail. Finally, the simulation results show that both the hard-decision algorithm and the soft-decision algorithm can recognize the parameters of frame synchronization words blindly. What's more, the improved algorithm can enhance the accuracy of blind recognition obviously.

  10. Soft Material-Enabled, Flexible Hybrid Electronics for Medicine, Healthcare, and Human-Machine Interfaces

    PubMed Central

    Herbert, Robert; Kim, Jong-Hoon; Kim, Yun Soung; Lee, Hye Moon

    2018-01-01

    Flexible hybrid electronics (FHE), designed in wearable and implantable configurations, have enormous applications in advanced healthcare, rapid disease diagnostics, and persistent human-machine interfaces. Soft, contoured geometries and time-dynamic deformation of the targeted tissues require high flexibility and stretchability of the integrated bioelectronics. Recent progress in developing and engineering soft materials has provided a unique opportunity to design various types of mechanically compliant and deformable systems. Here, we summarize the required properties of soft materials and their characteristics for configuring sensing and substrate components in wearable and implantable devices and systems. Details of functionality and sensitivity of the recently developed FHE are discussed with the application areas in medicine, healthcare, and machine interactions. This review concludes with a discussion on limitations of current materials, key requirements for next generation materials, and new application areas. PMID:29364861

  11. Observations of Soft Gamma Repeaters

    NASA Technical Reports Server (NTRS)

    Kouveliotou, Chryssa

    2004-01-01

    Magnetars (Soft Gamma Repeaters and Anomalous X-ray Pulsars) are a subclass of neutron stars characterized by their recurrent X-ray bursts. While in an active (bursting) state (lasting anywhere between days and years), they are emit&ng hundreds of predominantly soft (kT=30 kev), short (0.1-100 ms long) events. Their quiescent source x-ray light ewes exhibit puhlions rotational period rate changes (spin-down) indicate that their magnetic fields are extremely high, of the order of 10^14- 10^l5 G. Such high B-field objects, dubbed "magnetars", had been predicted to exist in 1992, but the first concrete observational evidence were obtained in 1998 for two of these sources. I will discuss here the history of Soft Gamma Repeaters, and their spectral, timing and flux characteristics both in the persistent and their burst emission.

  12. Soft Material-Enabled, Flexible Hybrid Electronics for Medicine, Healthcare, and Human-Machine Interfaces.

    PubMed

    Herbert, Robert; Kim, Jong-Hoon; Kim, Yun Soung; Lee, Hye Moon; Yeo, Woon-Hong

    2018-01-24

    Flexible hybrid electronics (FHE), designed in wearable and implantable configurations, have enormous applications in advanced healthcare, rapid disease diagnostics, and persistent human-machine interfaces. Soft, contoured geometries and time-dynamic deformation of the targeted tissues require high flexibility and stretchability of the integrated bioelectronics. Recent progress in developing and engineering soft materials has provided a unique opportunity to design various types of mechanically compliant and deformable systems. Here, we summarize the required properties of soft materials and their characteristics for configuring sensing and substrate components in wearable and implantable devices and systems. Details of functionality and sensitivity of the recently developed FHE are discussed with the application areas in medicine, healthcare, and machine interactions. This review concludes with a discussion on limitations of current materials, key requirements for next generation materials, and new application areas.

  13. Reversible nano-lithography for commercial approaches

    NASA Astrophysics Data System (ADS)

    Park, Jae Hong; Jang, Hyun Ik; Kim, Woo Choong; Yun, Hae S.; Park, Jun Yong; Jeon, Seok Woo; Kim, Hee Yeoun; Ahn, Chi Won

    2016-04-01

    The methodology suggested in this research provides the great possibility of creating nanostructures composed of various materials, such as soft polymer, hard polymer, and metal, as well as Si. Such nanostructures are required for a vast range of optical and display devices, photonic components, physical devices, energy devices including electrodes of secondary batteries, fuel cells, solar cells, and energy harvesters, biological devices including biochips, biomimetic or biosimilar structured devices, and mechanical devices including micro- or nano-scale sensors and actuators.

  14. Elastic Cherenkov effects in transversely isotropic soft materials-I: Theoretical analysis, simulations and inverse method

    NASA Astrophysics Data System (ADS)

    Li, Guo-Yang; Zheng, Yang; Liu, Yanlin; Destrade, Michel; Cao, Yanping

    2016-11-01

    A body force concentrated at a point and moving at a high speed can induce shear-wave Mach cones in dusty-plasma crystals or soft materials, as observed experimentally and named the elastic Cherenkov effect (ECE). The ECE in soft materials forms the basis of the supersonic shear imaging (SSI) technique, an ultrasound-based dynamic elastography method applied in clinics in recent years. Previous studies on the ECE in soft materials have focused on isotropic material models. In this paper, we investigate the existence and key features of the ECE in anisotropic soft media, by using both theoretical analysis and finite element (FE) simulations, and we apply the results to the non-invasive and non-destructive characterization of biological soft tissues. We also theoretically study the characteristics of the shear waves induced in a deformed hyperelastic anisotropic soft material by a source moving with high speed, considering that contact between the ultrasound probe and the soft tissue may lead to finite deformation. On the basis of our theoretical analysis and numerical simulations, we propose an inverse approach to infer both the anisotropic and hyperelastic parameters of incompressible transversely isotropic (TI) soft materials. Finally, we investigate the properties of the solutions to the inverse problem by deriving the condition numbers in analytical form and performing numerical experiments. In Part II of the paper, both ex vivo and in vivo experiments are conducted to demonstrate the applicability of the inverse method in practical use.

  15. Reporting requirements for skeletal digital radiography: comparison of soft-copy and hard-copy presentation.

    PubMed

    O'Connor, P J; Davies, A G; Fowler, R C; Lintott, D J; Bury, R F; Parkin, G J; Martinez, D; Saifuddin, A; Cowen, A R

    1998-04-01

    To assess diagnostic performance and reader preference when reporting results from digital hard-copy and two soft-copy formats of skeletal digital radiography. The data comprised hand radiographs of patients undergoing renal dialysis. Normal hand radiographs obtained in trauma patients were assessed as control images. One hundred fifteen images acquired with a photostimulable-phosphor computed radiography system were analyzed. Image selection and initial assessment were by consensus of two experienced radiologists, who graded the radiographic changes of hyperparathyroidism with the Ritz scoring system. The images were then presented to four readers in three formats: hard-copy output and soft-copy presentations at 2K2 and 1K2 resolutions. These readers scored pathologic change and image preference. The results were analyzed with the receiver operating characteristic technique. There was a significant improvement in diagnostic performance for both soft-copy formats relative to the hard-copy format (P < .001). No significant difference in diagnostic performance was found between the two soft-copy formats. There was a significant preference for both soft-copy formats relative to the hard-copy format (P < .01), with the 2K2 soft-copy images preferred to the 1K2 images (P < .01). Soft-copy reporting can provide superior diagnostic performance even for images viewed at a modest (1K2) resolution. The lack of difference between the two soft-copy formats has important economic implications with respect to departmental hardware requirements.

  16. School Soft Drink Availability and Consumption Among U.S. Secondary Students

    PubMed Central

    Terry-McElrath, Yvonne M.; O’Malley, Patrick M.; Johnston, Lloyd D.

    2013-01-01

    Background Consumption of sugar-sweetened beverages (SSBs) such as soft drinks has been associated with significantly increased energy intake and body weight. One strategy used to reduce soft drink consumption among adolescents has been reducing availability in schools; however, research is limited on associations between availability of soft drinks in school and student consumption. Purpose This study examines associations between regular and diet soft drink availability in schools and student consumption using data from 329 secondary schools and 9284 students. Methods Data were obtained from two sources: (1) nationally representative cross-sectional samples of students in Grades 8, 10, and 12 from U.S. public and private schools in 2010 and 2011 in the Monitoring the Future study; and (2) administrators of the same schools in the Youth, Education, and Society study. Multilevel modeling conducted in 2012 examined associations between school availability and student consumption controlling for student sociodemographics and school characteristics. Results In the total sample of more than 9000 students, regular and diet soft drink availability in school was not related to student consumption of these beverages in multivariate models. Yet, among African-American high school students, school regular and diet soft drink availability was significantly related to higher daily consumption (both before and after controlling for student and school factors). Conclusions Although removal of soft drinks from schools may not result in significantly lower overall student consumption, such actions may result in significant decreases in soft drink consumption for specific student groups. PMID:23683974

  17. Distributed phased array architecture study

    NASA Technical Reports Server (NTRS)

    Bourgeois, Brian

    1987-01-01

    Variations in amplifiers and phase shifters can cause degraded antenna performance, depending also on the environmental conditions and antenna array architecture. The implementation of distributed phased array hardware was studied with the aid of the DISTAR computer program as a simulation tool. This simulation provides guidance in hardware simulation. Both hard and soft failures of the amplifiers in the T/R modules are modeled. Hard failures are catastrophic: no power is transmitted to the antenna elements. Noncatastrophic or soft failures are modeled as a modified Gaussian distribution. The resulting amplitude characteristics then determine the array excitation coefficients. The phase characteristics take on a uniform distribution. Pattern characteristics such as antenna gain, half power beamwidth, mainbeam phase errors, sidelobe levels, and beam pointing errors were studied as functions of amplifier and phase shifter variations. General specifications for amplifier and phase shifter tolerances in various architecture configurations for C band and S band were determined.

  18. A micro X-ray computed tomography dataset of South African hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) containing scans of two rare specimens and three recently described species.

    PubMed

    Landschoff, Jannes; Du Plessis, Anton; Griffiths, Charles L

    2018-04-01

    Along with the conventional deposition of physical types at natural history museums, the deposition of 3-dimensional (3D) image data has been proposed for rare and valuable museum specimens, such as irreplaceable type material. Micro computed tomography (μCT) scan data of 5 hermit crab species from South Africa, including rare specimens and type material, depicted main identification characteristics of calcified body parts. However, low-image contrasts, especially in larger (>50 mm total length) specimens, did not allow sufficient 3D reconstructions of weakly calcified and fine characteristics, such as soft tissue of the pleon, mouthparts, gills, and setation. Reconstructions of soft tissue were sometimes possible, depending on individual sample and scanning characteristics. The raw data of seven scans are publicly available for download from the GigaDB repository. Calcified body parts visualized from μCT data can aid taxonomic validation and provide additional, virtual deposition of rare specimens. The use of a nondestructive, nonstaining μCT approach for taxonomy, reconstructions of soft tissue structures, microscopic spines, and setae depend on species characteristics. Constrained to these limitations, the presented dataset can be used for future morphological studies. However, our virtual specimens will be most valuable to taxonomists who can download a digital avatar for 3D examination. Simultaneously, in the event of physical damage to or loss of the original physical specimen, this dataset serves as a vital insurance policy.

  19. Experimental seismic behavior of a full-scale four-story soft-story wood-frame building with retrofits II: shake table test results

    Treesearch

    John W. van de Lindt; Pouria Bahmani; Gary Mochizuki; Steven E. Pryor; Mikhail Gershfeld; Jingjing Tian; Michael D. Symans; Douglas Rammer

    2016-01-01

    Soft-story wood-frame buildings have been recognized as a disaster preparedness problem for decades. The majority of these buildings were constructed from the 1920s to the 1960s and are prone to collapse during moderate to large earthquakes due to a characteristic deficiency in strength and stiffness in their first story. In order to propose and validate retrofit...

  20. Energetics of impulsive solar flares: Correlating BATSE hard x-ray bursts and the solar atmosphere's soft x-ray response

    NASA Technical Reports Server (NTRS)

    Newton, Elizabeth

    1996-01-01

    This investigation has involved the correlation of BATSE-observed solar hard X-ray emission with the characteristics of soft X-ray emitting plasma observed by the Yohkoh Bragg Crystal Spectrometers. The goal was to test the hypothesis that localized electron beam heating is the dominant energy transport mechanism in impulsive flares, as formulated in the thick-target electron-heated model of Brown.

  1. Numerical simulation of soft palate movement and airflow in human upper airway by fluid-structure interaction method

    NASA Astrophysics Data System (ADS)

    Sun, Xiuzhen; Yu, Chi; Wang, Yuefang; Liu, Yingxi

    2007-08-01

    In this paper, the authors present airflow field characteristics of human upper airway and soft palate movement attitude during breathing. On the basis of the data taken from the spiral computerized tomography images of a healthy person and a patient with Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS), three-dimensional models of upper airway cavity and soft palate are reconstructed by the method of surface rendering. Numerical simulation is performed for airflow in the upper airway and displacement of soft palate by fluid-structure interaction analysis. The reconstructed three-dimensional models precisely preserve the original configuration of upper airways and soft palate. The results of the pressure and velocity distributions in the airflow field are quantitatively determined, and the displacement of soft palate is presented. Pressure gradients of airway are lower for the healthy person and the airflow distribution is quite uniform in the case of free breathing. However, the OSAHS patient remarkably escalates both the pressure and velocity in the upper airway, and causes higher displacement of the soft palate. The present study is useful in revealing pathogenesis and quantitative mutual relationship between configuration and function of the upper airway as well as in diagnosing diseases related to anatomical structure and function of the upper airway.

  2. Performance analysis of adaptive equalization for coherent acoustic communications in the time-varying ocean environment.

    PubMed

    Preisig, James C

    2005-07-01

    Equations are derived for analyzing the performance of channel estimate based equalizers. The performance is characterized in terms of the mean squared soft decision error (sigma2(s)) of each equalizer. This error is decomposed into two components. These are the minimum achievable error (sigma2(0)) and the excess error (sigma2(e)). The former is the soft decision error that would be realized by the equalizer if the filter coefficient calculation were based upon perfect knowledge of the channel impulse response and statistics of the interfering noise field. The latter is the additional soft decision error that is realized due to errors in the estimates of these channel parameters. These expressions accurately predict the equalizer errors observed in the processing of experimental data by a channel estimate based decision feedback equalizer (DFE) and a passive time-reversal equalizer. Further expressions are presented that allow equalizer performance to be predicted given the scattering function of the acoustic channel. The analysis using these expressions yields insights into the features of surface scattering that most significantly impact equalizer performance in shallow water environments and motivates the implementation of a DFE that is robust with respect to channel estimation errors.

  3. Post-harvest and post-milling changes in wheat grain and flour quality characteristics

    USDA-ARS?s Scientific Manuscript database

    Soft red winter (SRW) wheat grain immediately after harvest and flour after milling were stored for 26 weeks and analyzed for comprehensive milling and baking quality characteristics at different time points to examine the consistency of the quality test results. Increases in falling number (FN) of ...

  4. Functional and nutritional characteristics of wheat grown in organic and conventional cropping systems

    USDA-ARS?s Scientific Manuscript database

    The effects of organic vs. conventional farming practices on wheat functional and nutritional characteristics were compared. Soft white winter wheat and hard red spring wheat were obtained from long-term replicated field plots near Pullman, Washington and Bozeman, Montana. Test weight, kernel weight...

  5. Static internal performance characteristics of two thrust reverser concepts for axisymmetric nozzles

    NASA Technical Reports Server (NTRS)

    Leavitt, L. D.; Re, R. J.

    1982-01-01

    The statis performance of two axisymmetric nozzle thrust reverser concepts was investigated. A rotating vane thrust reverser represented a concept in which reversing is accomplished upstream of the nozzle throat, and a three door reverser concept provided reversing downstream of the nozzle throat. Nozzle pressure ratio was varied from 2.0 to approximately 6.0. The results of this investigation indicate that both the rotating vane and three door reverser concepts were effective static thrust spoilers with the landing approach nozzle geometry and were capable of providing at least a 50 percent reversal of static thrust when fully deployed with the ground roll nozzle geometry.

  6. Soft X-ray FEL simulation in PAL-XFEL

    NASA Astrophysics Data System (ADS)

    Shim, Chi Hyun; Ko, In Soo; Parc, Yong Woon; Han, Jang Hui

    2015-10-01

    The soft X-ray beamline in the Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL) will provide a photon beam with a wavelength from 1 nm to 3 nm in the self-amplified spontaneous emission (SASE) mode by using an electron beam with a 3.15-GeV beam energy. Linearly polarized radiation will be supplied by using six planar undulators (PUs). The linearly-polarized radiation powers at 1 (3) nm can reach 10.2 (30) GW. Polarization of the radiation will be controlled by applying the reverse undulator tapering scheme to the PUs and adding two helical undulators (HUs). The circularly-polarized radiation powers at 1 (3) nm will be 3.11 (11.73) GW. The degrees of circular polarization will be larger than 0.99 for both wavelengths. Three options for the future upgrade of the beamline to increase the radiation power are proposed.

  7. Simultaneous covalent and noncovalent hybrid polymerizations

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

    Yu, Z.; Tantakitti, F.; Yu, T.

    Covalent and supramolecular polymers are two distinct forms of soft matter, composed of long chains of covalently and noncovalently linked structural units, respectively. We report a hybrid system formed by simultaneous covalent and supramolecular polymerizations of monomers. The process yields cylindrical fibers of uniform diameter that contain covalent and supramolecular compartments, a morphology not observed when the two polymers are formed independently. The covalent polymer has a rigid aromatic imine backbone with helicoidal conformation, and its alkylated peptide side chains are structurally identical to the monomer molecules of supramolecular polymers. In the hybrid system, covalent chains grow to higher averagemore » molar mass relative to chains formed via the same polymerization in the absence of a supramolecular compartment. The supramolecular compartments can be reversibly removed and re-formed to reconstitute the hybrid structure, suggesting soft materials with novel delivery or repair functions.« less

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

    Anastasiou, Charalampos; Duhr, Claude; Dulat, Falko

    We present methods to compute higher orders in the threshold expansion for the one-loop production of a Higgs boson in association with two partons at hadron colliders. This process contributes to the N 3LO Higgs production cross section beyond the soft-virtual approximation. We use reverse unitarity to expand the phase-space integrals in the small kinematic parameters and to reduce the coefficients of the expansion to a small set of master integrals. We describe two methods for the calculation of the master integrals. The first was introduced for the calculation of the soft triple-real radiation relevant to N 3LO Higgs production.more » The second uses a particular factorization of the three body phase-space measure and the knowledge of the scaling properties of the integral itself. Our result is presented as a Laurent expansion in the dimensional regulator, although some of the master integrals are computed to all orders in this parameter.« less

  9. Three-dimensional localization of nanoscale battery reactions using soft X-ray tomography.

    PubMed

    Yu, Young-Sang; Farmand, Maryam; Kim, Chunjoong; Liu, Yijin; Grey, Clare P; Strobridge, Fiona C; Tyliszczak, Tolek; Celestre, Rich; Denes, Peter; Joseph, John; Krishnan, Harinarayan; Maia, Filipe R N C; Kilcoyne, A L David; Marchesini, Stefano; Leite, Talita Perciano Costa; Warwick, Tony; Padmore, Howard; Cabana, Jordi; Shapiro, David A

    2018-03-02

    Battery function is determined by the efficiency and reversibility of the electrochemical phase transformations at solid electrodes. The microscopic tools available to study the chemical states of matter with the required spatial resolution and chemical specificity are intrinsically limited when studying complex architectures by their reliance on two-dimensional projections of thick material. Here, we report the development of soft X-ray ptychographic tomography, which resolves chemical states in three dimensions at 11 nm spatial resolution. We study an ensemble of nano-plates of lithium iron phosphate extracted from a battery electrode at 50% state of charge. Using a set of nanoscale tomograms, we quantify the electrochemical state and resolve phase boundaries throughout the volume of individual nanoparticles. These observations reveal multiple reaction points, intra-particle heterogeneity, and size effects that highlight the importance of multi-dimensional analytical tools in providing novel insight to the design of the next generation of high-performance devices.

  10. Enhancement of venous drainage with vein stripper for reversed pedicled neurocutaneous flaps.

    PubMed

    Sonmez, Erhan; Silistireli, Özlem Karataş; Karaaslan, Önder; Kamburoğlu, Haldun Onuralp; Safak, Tunc

    2013-05-01

    The flaps based on the vascular axis of superficial sensitive cutaneous nerves had gained increased popularity in reconstructive surgery because of such major advantages as preservation of major extremity arteries and avoidance of microsurgical procedures. However, postoperative venous congestion resulting in partial or total necrosis is still a common problem for these flaps. The aim of the current study is to introduce a new method for reducing the postoperative venous congestion of neural island flap with the results of reconstruction of the soft tissue defects of foot and ankle. This method was used to treat 19 patients with various chronic soft tissue defects of the foot and ankle between 2011 and 2012. We observed that the novel method presented in this report enables effective venous drainage, solving the postoperative venous congestion problem of these flaps. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  11. Soft magnetic properties of nanocrystalline FeRuGaSi-Hf alloy films and head characteristics for the embedded thin film tape head

    NASA Astrophysics Data System (ADS)

    Ohmori, H.; Shoji, M.; Kobayashi, T.; Yamamoto, T.; Sugiyama, Y.; Hayashi, K.; Hono, K.

    1996-04-01

    The Hf-added FeRuGaSi alloy film has an amorphous structure in the as-deposited state and becomes nanocrystalline after annealing. Due to this structure change from crystalline to amorphous by the addition of Hf, soft magnetic degradation of the film deposited on the slant grooved substrate, which is necessary for the sophisticated embedded thin film (ETF) head structure, is greatly suppressed and the undesirable film stress is relieved. The FeRuGaSi-Hf alloy film has higher resistivity and permeability at high frequencies than those of sendust film, and the read/write characteristics of this alloy film show better performance than sendust film.

  12. Low Power Consumption Design and Fabrication of Thin Film Core for Micro Fluxgate.

    PubMed

    Lv, Hui; Liu, Shibin

    2016-03-01

    The soft magnetic characteristic of core is a critical factor to performance of the micro fluxgate. Porous thin film core can be effectively used to decrease the value of saturation magnetic field strength (H(s)) and improve soft magnetic behavior. It is conducive to impelling the micro fluxgate toward the direction of low power consumption. In this work, negative photoresist is used to fabricate a porous core by MEMS technology. Through the processes of ultraviolet-lithography, the porous pattern transfer from the mask to the microstructure on silicon substrate. The experiment result complies with the anticipation and indicates that this MEMS technique can be applied to improve the characteristic of thin film core and decrease power consumption of fluxgate sensor.

  13. Deformation of Soft Tissue and Force Feedback Using the Smoothed Particle Hydrodynamics

    PubMed Central

    Liu, Xuemei; Wang, Ruiyi; Li, Yunhua; Song, Dongdong

    2015-01-01

    We study the deformation and haptic feedback of soft tissue in virtual surgery based on a liver model by using a force feedback device named PHANTOM OMNI developed by SensAble Company in USA. Although a significant amount of research efforts have been dedicated to simulating the behaviors of soft tissue and implementing force feedback, it is still a challenging problem. This paper introduces a kind of meshfree method for deformation simulation of soft tissue and force computation based on viscoelastic mechanical model and smoothed particle hydrodynamics (SPH). Firstly, viscoelastic model can present the mechanical characteristics of soft tissue which greatly promotes the realism. Secondly, SPH has features of meshless technique and self-adaption, which supply higher precision than methods based on meshes for force feedback computation. Finally, a SPH method based on dynamic interaction area is proposed to improve the real time performance of simulation. The results reveal that SPH methodology is suitable for simulating soft tissue deformation and force feedback calculation, and SPH based on dynamic local interaction area has a higher computational efficiency significantly compared with usual SPH. Our algorithm has a bright prospect in the area of virtual surgery. PMID:26417380

  14. Dynamic deformation of soft soil media: Experimental studies and mathematical modeling

    NASA Astrophysics Data System (ADS)

    Balandin, V. V.; Bragov, A. M.; Igumnov, L. A.; Konstantinov, A. Yu.; Kotov, V. L.; Lomunov, A. K.

    2015-05-01

    A complex experimental-theoretical approach to studying the problem of high-rate strain of soft soil media is presented. This approach combines the following contemporary methods of dynamical tests: the modified Hopkinson-Kolsky method applied tomedium specimens contained in holders and the method of plane wave shock experiments. The following dynamic characteristics of sand soils are obtained: shock adiabatic curves, bulk compressibility curves, and shear resistance curves. The obtained experimental data are used to study the high-rate strain process in the system of a split pressure bar, and the constitutive relations of Grigoryan's mathematical model of soft soil medium are verified by comparing the results of computational and natural test experiments of impact and penetration.

  15. Treatment in Borderline Class III Malocclusion: Orthodontic Camouflage (Extraction) Versus Orthognathic Surgery

    PubMed Central

    Rabie, A-Bakr M.; Wong, Ricky W.K.; Min, G.U.

    2008-01-01

    Aims: To investigate the differences in morphological characteristics of borderline class III patients who had undergone camouflage orthodontic treatment or orthognathic surgery, and to compare the treatment effects between these two modalities. Materials and Methods: Cephalograms of 25 patients (13 orthodontic, 12 surgical) with class III malocclusion were analyzed. All had a pretreatment ANB angle greater than -5º. Results: Using discriminant analysis, only Holdaway angle was selected to differentiate patients in the pretreatment stage. Seventy-two per cent patients were correctly classified. In the orthodontic group, reverse overjet was corrected by retraction of the lower incisors and downward and backward rotation of the mandible. The surgical group was corrected by setback of the lower anterior dentoalveolus and uprighting of the lower incisors. No difference was found in posttreatment soft tissue measurements between the two groups. Conclusions: Twelve degree for the Holdaway angle can be a guideline in determining the treatment modalities for borderline class III patients, but the preferences of operators and patients are also important. (2) Both therapeutic options should highlight changes in the lower dentoalveolus and lower incisors. (3) Both treatment modalities can achieve satisfactory improvements to the people. PMID:19088881

  16. Magnetization Dynamics of Amorphous Ribbons and Wires Studied by Inductance Spectroscopy

    PubMed Central

    Betancourt, Israel

    2010-01-01

    Inductance spectroscopy is a particular formulation variant of the well known complex impedance formalism typically used for the electric characterization of dielectric, ferroelectric, and piezoelectric materials. It has been successfully exploited as a versatile tool for characterization of the magnetization dynamics in amorphous ribbons and wires by means of simple experiments involving coils for sample holding and impedance analyzer equipment. This technique affords the resolution of the magnetization processes in soft magnetic materials, in terms of reversible deformation of pinned domain walls, domain wall displacements and spin rotation, for which characteristic parameters such as the alloy initial permeability and the relaxation frequencies, indicating the dispersion of each process, can be defined. Additionally, these parameters can be correlated with chemical composition variation, size effects and induced anisotropies, leading to a more physical insight for the understanding of the frequency dependent magnetic response of amorphous alloys, which is of prime interest for the development of novel applications in the field of telecommunication and sensing technologies. In this work, a brief overview, together with recent progress on the magnetization dynamics of amorphous ribbons, wires, microwires and biphase wires, is presented and discussed for the intermediate frequency interval between 10 Hz and 13 MHz. PMID:28879975

  17. Characterizing Adhesion between a Micropatterned Surface and a Soft Synthetic Tissue.

    PubMed

    Kern, Madalyn D; Qi, Yuan; Long, Rong; Rentschler, Mark E

    2017-01-31

    The work of adhesion and work of separation are characteristic properties of a contact interface that describe the amount of energy per unit area required to adhere or separate two contacting substrates, respectively. In this work, the authors present experimental and data analysis procedures that allow the contact interface between a soft synthetic tissue and a smooth or micropatterned poly(dimethylsiloxane) (PDMS) substrate to be characterized in terms of these characteristic parameters. Because of physical geometry limitations, the experimental contact geometry chosen for this study differs from conventional test geometries. Therefore, the authors used finite element modeling to develop correction factors specific to the experimental contact geometry used in this work. A work of adhesion was directly extracted from experimental data while the work of separation was estimated on the basis of experimental results. These values are compared to other theoretical calculations for validation. The results of this work indicate that the micropatterned PDMS substrate significantly decreases both the work of adhesion and work of separation as compared to a smooth PDMS substrate when in contact with a soft synthetic tissue substrate.

  18. Aortic Blood Flow Reversal Determines Renal Function: Potential Explanation for Renal Dysfunction Caused by Aortic Stiffening in Hypertension.

    PubMed

    Hashimoto, Junichiro; Ito, Sadayoshi

    2015-07-01

    Aortic stiffness determines the glomerular filtration rate (GFR) and predicts the progressive decline of the GFR. However, the underlying pathophysiological mechanism remains obscure. Recent evidence has shown a close link between aortic stiffness and the bidirectional (systolic forward and early diastolic reverse) flow characteristics. We hypothesized that the aortic stiffening-induced renal dysfunction is attributable to altered central flow dynamics. In 222 patients with hypertension, Doppler velocity waveforms were recorded at the proximal descending aorta to calculate the reverse/forward flow ratio. Tonometric waveforms were recorded to measure the carotid-femoral (aortic) and carotid-radial (peripheral) pulse wave velocities, to estimate the aortic pressure from the radial waveforms, and to compute the aortic characteristic impedance. In addition, renal hemodynamics was evaluated by duplex ultrasound. The estimated GFR was inversely correlated with the aortic pulse wave velocity, reverse/forward flow ratio, pulse pressure, and characteristic impedance, whereas it was not correlated with the peripheral pulse wave velocity or mean arterial pressure. The association between aortic pulse wave velocity and estimated GFR was independent of age, diabetes mellitus, hypercholesterolemia, and antihypertensive medication. However, further adjustment for the aortic reverse/forward flow ratio and pulse pressure substantially weakened this association, and instead, the reverse/forward flow ratio emerged as the strongest determinant of estimated GFR (P=0.001). A higher aortic reverse/forward flow ratio was also associated with lower intrarenal forward flow velocities. These results suggest that an increase in aortic flow reversal (ie, retrograde flow from the descending thoracic aorta toward the aortic arch), caused by aortic stiffening and impedance mismatch, reduces antegrade flow into the kidney and thereby deteriorates renal function. © 2015 American Heart Association, Inc.

  19. Robust and Soft Elastomeric Electronics Tolerant to Our Daily Lives.

    PubMed

    Sekiguchi, Atsuko; Tanaka, Fumiaki; Saito, Takeshi; Kuwahara, Yuki; Sakurai, Shunsuke; Futaba, Don N; Yamada, Takeo; Hata, Kenji

    2015-09-09

    Clothes represent a unique textile, as they simultaneously provide robustness against our daily activities and comfort (i.e., softness). For electronic devices to be fully integrated into clothes, the devices themselves must be as robust and soft as the clothes themselves. However, to date, no electronic device has ever possessed these properties, because all contain components fabricated from brittle materials, such as metals. Here, we demonstrate robust and soft elastomeric devices where every component possesses elastomeric characteristics with two types of single-walled carbon nanotubes added to provide the necessary electronic properties. Our elastomeric field effect transistors could tolerate every punishment our clothes experience, such as being stretched (elasticity: ∼ 110%), bent, compressed (>4.0 MPa, by a car and heels), impacted (>6.26 kg m/s, by a hammer), and laundered. Our electronic device provides a novel design principle for electronics and wide range applications even in research fields where devices cannot be used.

  20. Polymer-dispersed liquid crystal elastomers

    NASA Astrophysics Data System (ADS)

    Rešetič, Andraž; Milavec, Jerneja; Zupančič, Blaž; Domenici, Valentina; Zalar, Boštjan

    2016-10-01

    The need for mechanical manipulation during the curing of conventional liquid crystal elastomers diminishes their applicability in the field of shape-programmable soft materials and future applications in additive manufacturing. Here we report on polymer-dispersed liquid crystal elastomers, novel composite materials that eliminate this difficulty. Their thermal shape memory anisotropy is imprinted by curing in external magnetic field, providing for conventional moulding of macroscopically sized soft, thermomechanically active elastic objects of general shapes. The binary soft-soft composition of isotropic elastomer matrix, filled with freeze-fracture-fabricated, oriented liquid crystal elastomer microparticles as colloidal inclusions, allows for fine-tuning of thermal morphing behaviour. This is accomplished by adjusting the concentration, spatial distribution and orientation of microparticles or using blends of microparticles with different thermomechanical characteristics. We demonstrate that any Gaussian thermomechanical deformation mode (bend, cup, saddle, left and right twist) of a planar sample, as well as beat-like actuation, is attainable with bilayer microparticle configurations.

  1. Features Extraction of Flotation Froth Images and BP Neural Network Soft-Sensor Model of Concentrate Grade Optimized by Shuffled Cuckoo Searching Algorithm

    PubMed Central

    Wang, Jie-sheng; Han, Shuang; Shen, Na-na; Li, Shu-xia

    2014-01-01

    For meeting the forecasting target of key technology indicators in the flotation process, a BP neural network soft-sensor model based on features extraction of flotation froth images and optimized by shuffled cuckoo search algorithm is proposed. Based on the digital image processing technique, the color features in HSI color space, the visual features based on the gray level cooccurrence matrix, and the shape characteristics based on the geometric theory of flotation froth images are extracted, respectively, as the input variables of the proposed soft-sensor model. Then the isometric mapping method is used to reduce the input dimension, the network size, and learning time of BP neural network. Finally, a shuffled cuckoo search algorithm is adopted to optimize the BP neural network soft-sensor model. Simulation results show that the model has better generalization results and prediction accuracy. PMID:25133210

  2. Research Trends of Soft Actuators based on Electroactive Polymers and Conducting Polymers

    NASA Astrophysics Data System (ADS)

    Kaneto, K.

    2016-04-01

    Artificial muscles (or soft actuators) based on electroactive polymers (EAPs) are attractive power sources to drive human-like robots in place of electrical motor, because they are quiet, powerful, light weight and compact. Among EAPs for soft actuators, conducting polymers are superior in strain, stress, deformation form and driving voltage compared with the other EAPs. In this paper, the research trends of EAPs and conducting polymers are reviewed by retrieval of the papers and patents. The research activity of EAP actuators showed the maximum around 2010 and somehow declining now days. The reasons for the reducing activity are found to be partly due to problems of conducting polymer actuators for the practical application. The unique characteristics of conducting polymer actuators are mentioned in terms of the basic mechanisms of actuation, creeping, training effect and shape retention under high tensile loads. The issues and limitation of conducting polymer soft actuators are discussed.

  3. Injectable fillers: review of material and properties.

    PubMed

    Attenello, Natalie Huang; Maas, Corey S

    2015-02-01

    With an increasing understanding of the aging process and the rapidly growing interest in minimally invasive treatments, injectable facial fillers have changed the perspective for the treatment and rejuvenation of the aging face. Other than autologous fat and certain preformed implants, the collagen family products were the only Food and Drug Administration approved soft tissue fillers. But the overwhelming interest in soft tissue fillers had led to the increase in research and development of other products including bioengineered nonpermanent implants and permanent alloplastic implants. As multiple injectable soft tissue fillers and biostimulators are continuously becoming available, it is important to understand the biophysical properties inherent in each, as these constitute the clinical characteristics of the product. This article will review the materials and properties of the currently available soft tissue fillers: hyaluronic acid, calcium hydroxylapatite, poly-l-lactic acid, polymethylmethacrylate, and autologous fat (and aspirated tissue including stem cells). Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  4. Femtosecond resolution of soft mode dynamics in structural phase transitions

    NASA Technical Reports Server (NTRS)

    Dougherty, Thomas P.; Wiederrecht, Gary P.; Nelson, Keith A.; Garrett, Mark H.; Jensen, Hans P.; Warde, Cardinal

    1992-01-01

    The microscopic pathway along which ions or molecules in a crystal move during structural phase transition can often be described in terms of a collective vibrational mode of the lattice. In many cases, this mode, called a 'soft' phonon mode because of its characteristically low frequency near the phase transition temperature, is difficult to characterize through conventional frequency-domain spectroscopies such as light or neutron scattering. A femtosecond time-domain analog of light-scattering spectroscopy called impulsive stimulated Raman scattering (ISRS) has been used to examine the soft modes of two perovskite ferroelectric crystals. The low-frequency lattice dynamics of KNbO3 and BaTiO3 are clarified in a manner that permits critical evaluation of microscopic models for their ferroelectric transitions. The results illustrate the advantages of ISRS over conventional Raman spectroscopy of low-frequency, heavily damped soft modes.

  5. Spectral variations of LMC X-3 observed with Ginga

    NASA Technical Reports Server (NTRS)

    Ebisawa, Ken; Makino, Fumiyoshi; Mitsuda, Kazuhisa; Belloni, Tomaso; Cowley, Anne P.; Schmidtke, Paul C.; Treves, Aldo

    1993-01-01

    The prime black hole candidate LMC X-3 was observed over three years with the Ginga satellite, and a characteristic spectral variation was found accompanying the periodic intensity variation of about 198 (or possibly about 99) days (Cowley et al., 1991). The energy spectrum of LMC X-3 consists of the soft, thermal component and the hard, power-law component, which are respectively dominant below and above about 9 keV. The soft component, which carries most of the X-ray intensity, shows a clear correlation between the intensity and the hardness, while the hard component varies independently of the soft component. It was found that the spectral variation of the soft component is well described by an optically thick accretion disk model with a remarkably constant innermost radius and variable mass accretion rate. The constancy of the innermost radius suggests it is related to the mass of the central object.

  6. Remote control of soft nano-objects by light using azobenzene containing surfactants

    NASA Astrophysics Data System (ADS)

    Santer, Svetlana

    2018-01-01

    We review recent progress in the field of light responsive soft nano-objects. These are systems the shape, size, surface area and surface energy of which can be easily changed by low-intensity external irradiation. Here we shall specifically focus on microgels, DNA molecules, polymer brushes and colloidal particles. One convenient way to render these objects photosensitive is to couple them via ionic and/or hydrophobic interactions with azobenzene containing surfactants in a non-covalent way. The advantage of this strategy is that these surfactants can make any type of charged object light responsive without the need for possibly complicated (and irreversible) chemical conjugation. In the following, we will exclusively discuss only photosensitive surfactant systems. These contain a charged head and a hydrophobic tail into which an azobenzene group is incorporated, which can undergo reversible photo-isomerization from a trans- to a cis-configuration under UV illumination. These kinds of photo-isomerizations occur on a picosecond timescale and are fully reversible. The two isomers in general possess different polarity, i.e. the trans-state is less polar with a dipole moment of usually close to 0 Debye, while the cis-isomer has a dipole moment up to 3 Debye or more, depending on additional phenyl ring substituents. As part of the hydrophobic tail of a surfactant molecule, the photo-isomerization also changes the hydrophobicity of the molecule as a whole and hence its solubility, surface energy, and strength of interaction with other substances. Being a molecular actuator, which converts optical energy in to mechanical work, the azobenzene group in the shape of surfactant molecule can be utilized in order to actuate matter on larger time and length scale. In this paper we show several interesting examples, where azobenzene containing surfactants play the role of a transducer mediating between different states of size, shape, surface energy and spatial arrangement of various nanoscale soft-material systems.

  7. Electrophoresis of a charged soft particle in a charged cavity with arbitrary double-layer thickness.

    PubMed

    Chen, Wei J; Keh, Huan J

    2013-08-22

    An analysis for the quasi-steady electrophoretic motion of a soft particle composed of a charged spherical rigid core and an adsorbed porous layer positioned at the center of a charged spherical cavity filled with an arbitrary electrolyte solution is presented. Within the porous layer, frictional segments with fixed charges are assumed to distribute uniformly. Through the use of the linearized Poisson-Boltzmann equation and the Laplace equation, the equilibrium double-layer potential distribution and its perturbation caused by the applied electric field are separately determined. The modified Stokes and Brinkman equations governing the fluid flow fields outside and inside the porous layer, respectively, are solved subsequently. An explicit formula for the electrokinetic migration velocity of the soft particle in terms of the fixed charge densities on the rigid core surface, in the porous layer, and on the cavity wall is obtained from a balance between its electrostatic and hydrodynamic forces. This formula is valid for arbitrary values of κa, λa, r0/a, and a/b, where κ is the Debye screening parameter, λ is the reciprocal of the length characterizing the extent of flow penetration inside the porous layer, a is the radius of the soft particle, r0 is the radius of the rigid core of the particle, and b is the radius of the cavity. In the limiting cases of r0 = a and r0 = 0, the migration velocity for the charged soft sphere reduces to that for a charged impermeable sphere and that for a charged porous sphere, respectively, in the charged cavity. The effect of the surface charge at the cavity wall on the particle migration can be significant, and the particle may reverse the direction of its migration.

  8. Research on the Environmental Performance Evaluation of Electronic Waste Reverse Logistics Enterprise

    NASA Astrophysics Data System (ADS)

    Yang, Yu-Xiang; Chen, Fei-Yang; Tong, Tong

    According to the characteristic of e-waste reverse logistics, environmental performance evaluation system of electronic waste reverse logistics enterprise is proposed. We use fuzzy analytic hierarchy process method to evaluate the system. In addition, this paper analyzes the enterprise X, as an example, to discuss the evaluation method. It's important to point out attributes and indexes which should be strengthen during the process of ewaste reverse logistics and provide guidance suggestions to domestic e-waste reverse logistics enterprises.

  9. The relationship between grain hardness, dough mixing parameters and bread-making quality in winter wheat.

    PubMed

    Salmanowicz, Bolesław P; Adamski, Tadeusz; Surma, Maria; Kaczmarek, Zygmunt; Karolina, Krystkowiak; Kuczyńska, Anetta; Banaszak, Zofia; Lugowska, Bogusława; Majcher, Małgorzata; Obuchowski, Wiktor

    2012-01-01

    The influence of grain hardness, determined by using molecular markers and physical methods (near-infrared (NIR) technique and particle size index-PSI) on dough characteristics, which in turn were determined with the use of a farinograph and reomixer, as well as bread-making properties were studied. The material covered 24 winter wheat genotypes differing in grain hardness. The field experiment was conducted at standard and increased levels of nitrogen fertilization. Results of molecular analyses were in agreement with those obtained by the use of physical methods for soft-grained lines. Some lines classified as hard (by physical methods) appeared to have the wild-type Pina and Pinb alleles, similar to soft lines. Differences in dough and bread-making properties between lines classified as hard and soft on the basis of molecular data appeared to be of less significance than the differences between lines classified as hard and soft on the basis of physical analyses of grain texture. Values of relative grain hardness at the increased nitrogen fertilization level were significantly higher. At both fertilization levels the NIR parameter determining grain hardness was significantly positively correlated with the wet gluten and sedimentation values, with most of the rheological parameters and bread yield. Values of this parameter correlated with quality characteristics in a higher degree than values of particle size index.

  10. The Relationship Between Grain Hardness, Dough Mixing Parameters and Bread-Making Quality in Winter Wheat

    PubMed Central

    Salmanowicz, Bolesław P.; Adamski, Tadeusz; Surma, Maria; Kaczmarek, Zygmunt; Karolina, Krystkowiak; Kuczyńska, Anetta; Banaszak, Zofia; Ługowska, Bogusława; Majcher, Małgorzata; Obuchowski, Wiktor

    2012-01-01

    The influence of grain hardness, determined by using molecular markers and physical methods (near-infrared (NIR) technique and particle size index—PSI) on dough characteristics, which in turn were determined with the use of a farinograph and reomixer, as well as bread-making properties were studied. The material covered 24 winter wheat genotypes differing in grain hardness. The field experiment was conducted at standard and increased levels of nitrogen fertilization. Results of molecular analyses were in agreement with those obtained by the use of physical methods for soft-grained lines. Some lines classified as hard (by physical methods) appeared to have the wild-type Pina and Pinb alleles, similar to soft lines. Differences in dough and bread-making properties between lines classified as hard and soft on the basis of molecular data appeared to be of less significance than the differences between lines classified as hard and soft on the basis of physical analyses of grain texture. Values of relative grain hardness at the increased nitrogen fertilization level were significantly higher. At both fertilization levels the NIR parameter determining grain hardness was significantly positively correlated with the wet gluten and sedimentation values, with most of the rheological parameters and bread yield. Values of this parameter correlated with quality characteristics in a higher degree than values of particle size index. PMID:22605973

  11. Reversibly pH-responsive polyurethane membranes for on-demand intravaginal drug delivery.

    PubMed

    Kim, Seungil; Chen, Yufei; Ho, Emmanuel A; Liu, Song

    2017-01-01

    To provide better protection for women against sexually transmitted infections, on-demand intravaginal drug delivery was attempted by synthesizing reversibly pH-sensitive polyether-polyurethane copolymers using poly(ethylene glycol) (PEG) and 1,4-bis(2-hydroxyethyl)piperazine (HEP). Chemical structure and thermo-characteristics of the synthesized polyurethanes were confirmed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), 1 H-nuclear magnetic resonance ( 1 H-NMR), and melting point testing. Membranes were cast by solvent evaporation method using the prepared pH-sensitive polyurethanes. The impact of varying pH on membrane swelling and surface morphology was evaluated via swelling ratio change and scanning electron microscopy (SEM). The prepared pH-responsive membranes showed two times higher swelling ratio at pH 4 than pH 7 and pH-triggered switchable surface morphology change. The anionic anti-inflammatory drug diclofenac sodium (NaDF) was used as a model compound for release studies. The prepared pH-responsive polyurethane membranes allowed continuous NaDF release for 24h and around 20% release of total NaDF within 3h at pH 7 but little-to-no drug release at pH 4.5. NaDF permeation across the prepared membranes demonstrated a reversible pH-responsiveness. The pH-responsive polyurethane membranes did not show any noticeable negative impact on vaginal epithelial cell viability or induction of pro-inflammatory cytokine production compared to controls. Overall, the non-cytotoxic HEP-based pH-responsive polyurethane demonstrated its potential to be used in membrane-based implants such as intravaginal rings to achieve on-demand "on-and-off" intravaginal drug delivery. A reversible and sharp switch between "off" and "on" drug release is achieved for the first time through new pH-sensitive polyurethane membranes, which can serve as window membranes in reservoir-type intravaginal rings for on-demand drug delivery to prevent sexually transmitted infections (STIs). Close to zero drug release occurs at the normal vaginal pH (4.5) for minimal side effects. Drug release is only triggered by elevation of pH to 7 during heterosexual intercourse. The reversibly sharp and fast "on-and-off" switch arises from the creative incorporation of a pH-sensitive monomer in the soft segment of polyurethane. This polyurethane biomaterial holds great potential to better protect women who are generally at higher risk and are more vulnerable to STIs. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. School soft drink availability and consumption among U.S. secondary students.

    PubMed

    Terry-McElrath, Yvonne M; O'Malley, Patrick M; Johnston, Lloyd D

    2013-06-01

    Consumption of sugar-sweetened beverages (SSBs) such as soft drinks has been associated with significantly increased energy intake and body weight. One strategy used to reduce soft drink consumption among adolescents has been reducing availability in schools; however, research is limited on associations between availability of soft drinks in school and student consumption. This study examines associations between regular and diet soft drink availability in schools and student consumption using data from 329 secondary schools and 9284 students. Data were obtained from two sources: (1) nationally representative cross-sectional samples of students in Grades 8, 10, and 12 from U.S. public and private schools in 2010 and 2011 in the Monitoring the Future study and (2) administrators of the same schools in the Youth, Education, and Society study. Multilevel modeling conducted in 2012 examined associations between school availability and student consumption controlling for student sociodemographics and school characteristics. In the total sample of more than 9000 students, regular and diet soft drink availability in school was not related to student consumption of these beverages in multivariate models. Yet, among African-American high school students, school regular and diet soft drink availability was significantly related to higher daily consumption (both before and after controlling for student and school factors). Although removal of soft drinks from schools may not result in significantly lower overall student consumption, such actions may result in significant decreases in soft drink consumption for specific student groups. Copyright © 2013 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  13. Biology of soft tissue wound healing and regeneration--consensus report of Group 1 of the 10th European Workshop on Periodontology.

    PubMed

    Hämmerle, Christoph H F; Giannobile, William V

    2014-04-01

    The scope of this consensus was to review the biological processes of soft tissue wound healing in the oral cavity and to histologically evaluate soft tissue healing in clinical and pre-clinical models. To review the current knowledge regarding the biological processes of soft tissue wound healing at teeth, implants and on the edentulous ridge. Furthermore, to review soft tissue wound healing at these sites, when using barrier membranes, growth and differentiation factors and soft tissue substitutes. Searches of the literature with respect to recessions at teeth and soft tissue deficiencies at implants, augmentation of the area of keratinized tissue and soft tissue volume were conducted. The available evidence was collected, categorized and summarized. Oral mucosal and skin wound healing follow a similar pattern of the four phases of haemostasis, inflammation, proliferation and maturation/matrix remodelling. The soft connective tissue determines the characteristics of the overlaying oral epithelium. Within 7-14 days, epithelial healing of surgical wounds at teeth is completed. Soft tissue healing following surgery at implants requires 6-8 weeks for maturation. The resulting tissue resembles scar tissue. Well-designed pre-clinical studies providing histological data have been reported describing soft tissue wound healing, when using barrier membranes, growth and differentiation factors and soft tissue substitutes. Few controlled clinical studies with low numbers of patients are available for some of the treatments reviewed at teeth. Whereas, histological new attachment has been demonstrated in pre-clinical studies resulting from some of the treatments reviewed, human histological data commonly report a lack of new attachment but rather long junctional epithelial attachment and connective tissue adhesion. Regarding soft tissue healing at implants human data are very scarce. Oral soft tissue healing at teeth, implants and the edentulous ridge follows the same phases as skin wound healing. Histological studies in humans have not reported new attachment formation at teeth for the indications studied. Human histological data of soft tissue wound healing at implants are limited. The use of barriers membranes, growth and differentiation factors and soft tissue substitutes for the treatment of localized gingival/mucosal recessions, insufficient amount of keratinized tissue and insufficient soft tissue volume is at a developing stage. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Risk factors for pedicled flap necrosis in hand soft tissue reconstruction: a multivariate logistic regression analysis.

    PubMed

    Gong, Xu; Cui, Jianli; Jiang, Ziping; Lu, Laijin; Li, Xiucun

    2018-03-01

    Few clinical retrospective studies have reported the risk factors of pedicled flap necrosis in hand soft tissue reconstruction. The aim of this study was to identify non-technical risk factors associated with pedicled flap perioperative necrosis in hand soft tissue reconstruction via a multivariate logistic regression analysis. For patients with hand soft tissue reconstruction, we carefully reviewed hospital records and identified 163 patients who met the inclusion criteria. The characteristics of these patients, flap transfer procedures and postoperative complications were recorded. Eleven predictors were identified. The correlations between pedicled flap necrosis and risk factors were analysed using a logistic regression model. Of 163 skin flaps, 125 flaps survived completely without any complications. The pedicled flap necrosis rate in hands was 11.04%, which included partial flap necrosis (7.36%) and total flap necrosis (3.68%). Soft tissue defects in fingers were noted in 68.10% of all cases. The logistic regression analysis indicated that the soft tissue defect site (P = 0.046, odds ratio (OR) = 0.079, confidence interval (CI) (0.006, 0.959)), flap size (P = 0.020, OR = 1.024, CI (1.004, 1.045)) and postoperative wound infection (P < 0.001, OR = 17.407, CI (3.821, 79.303)) were statistically significant risk factors for pedicled flap necrosis of the hand. Soft tissue defect site, flap size and postoperative wound infection were risk factors associated with pedicled flap necrosis in hand soft tissue defect reconstruction. © 2017 Royal Australasian College of Surgeons.

  15. Pathologic features of fatal shark attacks.

    PubMed

    Byard, R W; Gilbert, J D; Brown, K

    2000-09-01

    To examine the pattern of injuries in cases of fatal shark attack in South Australian waters, the authors examined the files of their institution for all cases of shark attack in which full autopsies had been performed over the past 25 years, from 1974 to 1998. Of the seven deaths attributed to shark attack during this period, full autopsies were performed in only two cases. In the remaining five cases, bodies either had not been found or were incomplete. Case 1 was a 27-year-old male surfer who had been attacked by a shark. At autopsy, the main areas of injury involved the right thigh, which displayed characteristic teeth marks, extensive soft tissue damage, and incision of the femoral artery. There were also incised wounds of the right wrist. Bony injury was minimal, and no shark teeth were recovered. Case 2 was a 26-year-old male diver who had been attacked by a shark. At autopsy, the main areas of injury involved the left thigh and lower leg, which displayed characteristic teeth marks, extensive soft tissue damage, and incised wounds of the femoral artery and vein. There was also soft tissue trauma to the left wrist, with transection of the radial artery and vein. Bony injury was minimal, and no shark teeth were recovered. In both cases, death resulted from exsanguination following a similar pattern of soft tissue and vascular damage to a leg and arm. This type of injury is in keeping with predator attack from underneath or behind, with the most severe injuries involving one leg. Less severe injuries to the arms may have occurred during the ensuing struggle. Reconstruction of the damaged limb in case 2 by sewing together skin, soft tissue, and muscle bundles not only revealed that no soft tissue was missing but also gave a clearer picture of the pattern of teeth marks, direction of the attack, and species of predator.

  16. Predictors of the postoperative range of finger motion for comminuted periarticular metacarpal and phalangeal fractures treated with a titanium plate.

    PubMed

    Shimizu, Takamasa; Omokawa, Shohei; Akahane, Manabu; Murata, Keiichi; Nakano, Kenichi; Kawamura, Kenji; Tanaka, Yasuhito

    2012-06-01

    Plate and screw fixation was introduced for complex fractures of the hand. Several risk factors for a poor functional outcome have been identified, but there is a paucity of evidence regarding predictors of finger stiffness in difficult hand fractures. The purpose of this prospective cohort study was to identify independent prognostic factors of the postoperative total active motion (%TAM) in the treatment of metacarpal and phalangeal fractures. Seventy-two patients (62 males, 10 females; 37±15 years) with periarticular fractures involving metaphyseal comminution and displacement were evaluated at a minimum of 1 year following surgery. There were 49 phalangeal bone fractures, 30 intra-articular fractures and 20 associated soft-tissue injuries. The locations of plate placement were lateral in 42 patients and dorsal in 30. The mean duration from injury to surgery was 7.6 days (range, 0-40 days). There were eight examined variables related to patient characteristics (age, gender and hand dominance), fracture characteristics (fracture location, joint involvement and associated soft-tissue injury) and surgical variables (location of plate placement and duration from injury to surgery). Univariate and multivariate linear regression analysis were used to identify the degree to which variables affect %TAM at the final follow-up. Univariate analysis indicated moderate correlations of %TAM with fracture location, associated soft-tissue injury and age. Multiple linear regression modelling including fracture location, age and associated soft-tissue injury resulted in formulae that could account for 46.3% of the variability in %TAM: fracture location (β=-0.388, p<0.001), age (β=-0.339, p<0.001) and associated soft-tissue injury (β=-0.296, p=0.002). Phalangeal fracture, increasing age and associated soft-tissue injury were important risk factors to identify the postoperative %TAM in the treatment of comminuted periarticular metacarpal or phalangeal fracture with a titanium plate. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Holographic arrays for multi-path imaging artifact reduction

    DOEpatents

    McMakin, Douglas L.; Sheen, David M.; Hall, Thomas E.

    2007-11-13

    A method and apparatus to remove human features utilizing at least one transmitter transmitting a signal between 200 MHz and 1 THz, the signal having at least one characteristic of elliptical polarization, and at least one receiver receiving the reflection of the signal from the transmitter. A plurality of such receivers and transmitters are arranged together in an array which is in turn mounted to a scanner, allowing the array to be passed adjacent to the surface of the item being imaged while the transmitter is transmitting electromagnetic radiation. The array is passed adjacent to the surface of the item, such as a human being, that is being imaged. The portions of the received signals wherein the polarity of the characteristic has been reversed and those portions of the received signal wherein the polarity of the characteristic has not been reversed are identified. An image of the item from those portions of the received signal wherein the polarity of the characteristic was reversed is then created.

  18. Analysis of imaging characteristics of primary malignant bone tumors in children

    PubMed Central

    Sun, Yingwei; Liu, Xueyong; Pan, Shinong; Deng, Chunbo; Li, Xiaohan; Guo, Qiyong

    2017-01-01

    The present study aimed to investigate the imaging characteristics of primary malignant bone tumors in children. The imaging results of 34 children with primary malignant bone tumors confirmed by histopathological diagnosis between March 2008 and January 2014 were retrospectively analyzed. In total, 25 patients had osteosarcoma, with radiography and computed tomography (CT) showing osteolytic bone destruction or/and osteoblastic bone sclerosis, an aggressive periosteal reaction, a soft-tissue mass and cancerous bone. The tumors appeared as mixed magnetic resonance imaging (MRI) signals that were inhomogeneously enhanced. A total of 5 patients presented with Ewing sarcoma, with radiography and CT showing invasive bone destruction and a soft-tissue mass. Of the 5 cases, 2 showed a laminar periosteal reaction. The tumors were shown to have mixed low signal on T1-weighted images (T1WI) and high signal on T2-weighted images (T2WI); 1 case showed marked inhomogeneous enhancement. Another 3 patients exhibited chondrosarcoma. Of these cases, 1 was adjacent to the cortex of the proximal tibia, and presented with local cortical bone destruction and a soft-tissue mass containing scattered punctate and amorphous calcifications. MRI revealed mixed low T1 signal and high T2 signals. Another case was located in the medullary cavity of the distal femur, with radiography revealing a localized periosteal reaction. The tumor appeared with mixed MRI signals, and with involvement of the epiphysis and epiphyseal plates. Radiography and CT of the third case showed bone destruction in the right pubic ramus, with patchy punctate, cambered calcifications in the soft-tissue mass. MRI of the soft-tissue mass revealed isointensity on T1WI and heterogeneous hyperintensity on T2WI. Ossifications and the septum appeared as low T1WI and T2WI. Of the 34 patients, 1 patient presented with lymphoma involving the T12, L1 and L2 vertebrae. CT showed vertebral bone destruction, a soft-tissue mass and a compression fracture of L1. MRI showed a soft-tissue mass with low T1 signal and high T2 signal and marked inhomogeneous enhancement. Overall, osteosarcoma was the most common primary malignant bone tumor, followed by Ewing sarcoma, chondrosarcoma and lymphoma. Osteoblastic or osteolytic bone destruction, an invasive periosteal reaction, soft-tissue masses, a tumor matrix and inhomogeneous enhancement were important imaging features of malignant bone tumors. PMID:29113210

  19. Puroindoline genes introduced into durum wheat reduce milling energy and change milling behavior similar to soft common wheats

    USDA-ARS?s Scientific Manuscript database

    Grain physical characteristics and milling behavior of a durum wheat line in which both wild-type puroindoline alleles were translocated and stabilized after backcrossing (Svevo-Pin) were compared with the parent line (Svevo). The only observed differences between grain characteristics were the mech...

  20. Bran characteristics influencing quality attributes of whole wheat Chinese steamed bread

    USDA-ARS?s Scientific Manuscript database

    This study investigated the variations in the characteristics of brans obtained from a pilot-scale milling of 17 soft red winter wheat varieties and their influences on the quality of whole wheat northern-style Chinese steamed bread (CSB) prepared from blends of a base flour and brans of different w...

  1. Vapomechanically Responsive Motion of Microchannel-Programmed Actuators.

    PubMed

    Zhang, Lidong; Naumov, Pancˇe; Du, Xuemin; Hu, Zhigao; Wang, Juan

    2017-10-01

    Materials that respond rapidly and reversibly to external stimuli currently stand among the top choices as actuators for real-world applications. Here, a series of programmable actuators fabricated as single- or bilayer elements is described that can reversibly respond to minute concentrations of acetone vapors. By using templates, microchannel structures are replicated onto the surface of two highly elastic polymers, polyvinylidene fluoride (PVDF) and polyvinyl alcohol, to induce chiral coiling upon exposure to acetone vapors. The vapomechanical coiling is reversible and can be conducted repeatedly over 100 times without apparent fatigue. If they are immersed in liquid acetone, the actuators are saturated with the solvent and temporarily lose their motility but regain their shape and activity within seconds after the solvent evaporates. The desorption of acetone from the PVDF layer is four times faster than its adsorption, and the actuator composed of a single PVDF layer maintains its ability to move over an acetone-soaked filter paper even after several days. The controllable and reproducible sensing capability of this smart material can be utilized for actuating dynamic elements in soft robotics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Characterization of Polystyrene Soft Nanoparticles Using Small Angle Neutron Scattering

    NASA Astrophysics Data System (ADS)

    Martin, Halie; White, Tyler; Saito, Tomonori; Dadmun, Mark

    Polymer nanocomposites have become a prominent area of research recently. With a growing variety of nanoparticles available, research probing the influence of particle morphology on the overall nanocomposite properties is also increasing. Nanoparticle dispersion is controlled by both the chemical nature and morphology of the nanoparticle where a crosslinked, fuzzy organic nanoparticle is anticipated to enhance the overall miscibility and create a homogenous dispersion within a like-polymer matrix. A semi-batch microemulsion polymerization forms organic, soft nanoparticles where the precise structure of the nanoparticle is controlled by monomer rate of addition and crosslinking density. We will report small angle neutron scattering results that correlate synthetic conditions to the structural characteristics of soft nanoparticles. This analysis provides characterization of the individual nanoparticle molecular weight, the radius of the crosslinked core, the thickness of the fuzzy interfacial layer, and provides insight into the overall topography of the soft nanoparticle. This research provides a pathway to investigate the effect of nanoscale structural features of the nanoparticle on their individual properties and those of nanocomposites that contain these soft nanoparticles. DOE-BES, Division of Materials Sciences and Engineering.

  3. Moderate point: Balanced entropy and enthalpy contributions in soft matter

    NASA Astrophysics Data System (ADS)

    He, Baoji; Wang, Yanting

    2017-03-01

    Various soft materials share some common features, such as significant entropic effect, large fluctuations, sensitivity to thermodynamic conditions, and mesoscopic characteristic spatial and temporal scales. However, no quantitative definitions have yet been provided for soft matter, and the intrinsic mechanisms leading to their common features are unclear. In this work, from the viewpoint of statistical mechanics, we show that soft matter works in the vicinity of a specific thermodynamic state named moderate point, at which entropy and enthalpy contributions among substates along a certain order parameter are well balanced or have a minimal difference. Around the moderate point, the order parameter fluctuation, the associated response function, and the spatial correlation length maximize, which explains the large fluctuation, the sensitivity to thermodynamic conditions, and mesoscopic spatial and temporal scales of soft matter, respectively. Possible applications to switching chemical bonds or allosteric biomachines determining their best working temperatures are also briefly discussed. Project supported by the National Basic Research Program of China (Grant No. 2013CB932804) and the National Natural Science Foundation of China (Grant Nos. 11274319 and 11421063).

  4. Prediction of soft soil foundation settlement in Guangxi granite area based on fuzzy neural network model

    NASA Astrophysics Data System (ADS)

    Luo, Junhui; Wu, Chao; Liu, Xianlin; Mi, Decai; Zeng, Fuquan; Zeng, Yongjun

    2018-01-01

    At present, the prediction of soft foundation settlement mostly use the exponential curve and hyperbola deferred approximation method, and the correlation between the results is poor. However, the application of neural network in this area has some limitations, and none of the models used in the existing cases adopted the TS fuzzy neural network of which calculation combines the characteristics of fuzzy system and neural network to realize the mutual compatibility methods. At the same time, the developed and optimized calculation program is convenient for engineering designers. Taking the prediction and analysis of soft foundation settlement of gully soft soil in granite area of Guangxi Guihe road as an example, the fuzzy neural network model is established and verified to explore the applicability. The TS fuzzy neural network is used to construct the prediction model of settlement and deformation, and the corresponding time response function is established to calculate and analyze the settlement of soft foundation. The results show that the prediction of short-term settlement of the model is accurate and the final settlement prediction result has certain engineering reference value.

  5. Precessional Switching of Thin Nanomagnets with Uniaxial Anisotropy

    NASA Astrophysics Data System (ADS)

    Devolder, Thibaut; Schumacher, Hans Werner; Chappert, Claude

    This review describes the evolution of the magnetization of uniaxial thin magnets when subjected to fast-rising magnetic-field pulses. We report detailed "all-electrical" experimental investigations of precessional switching on soft uniaxial micrometer-sized thin magnets, and we discuss them using a comprehensive, mostly analytical framework. General criteria are derived for the analytical assessment of the switching ability of any arbitrary set of experimental parameters. For this, we start from the Landau-Lifshitz equation and first consider the precessional switching in a much idealized macrospin, easy-plane loss-free system. We then test the main outputs of this model with time-resolved experiments on advanced Magnetic Random Access Memories (MRAM) cells. Using applied fields above the anisotropy field H k , we prove the quasiperiodic nature of the magnetization trajectory and we demonstrate experimental conditions ensuring a sub-200 ps ballistic magnetization reversal. We then upgrade our model accuracy by taking into account the uniaxial anisotropy and the behavior in hard-axis fields of the order of H k . We derive a simple though reliable estimate of the switching speed; its limiting factors highlight the experimental poor switching reproducibility when close to the minimal hard-axis reversal field H k /2. The latter field does not correspond to the minimal energy cost of the reversal, whose prospective evolution in the future generations of MRAM is predicted. Small departures from the macrospin state are discussed. The effect of damping is modeled using perturbation theory. Finite damping alters the precessional motion periodicity and puts some constraints on the field rise time. A special focus is dedicated to the relaxation-dominated precessional switching: the minimal hard-axis field triggering the switching is shown to be above H k /2 by an extra field cost linked to the damping constant times the square root of M S H k . Finally, the selective addressing and the direct-write of a magnetic cell with combined easy-axis and hard-axis fields are studied. We introduce the concept of bounce and revisit the dynamical astroid to derive the related characteristic reversal durations and their margins. We propose a field timing that is immune to the delay jitter between the combined addressing fields. We finish by investigating briefly the challenges and the promises of the "precessional" strategy for future MRAM generations.

  6. Static performance of vectoring/reversing non-axisymmetric nozzles

    NASA Technical Reports Server (NTRS)

    Willard, C. M.; Capone, F. J.; Konarski, M.; Stevens, H. L.

    1977-01-01

    An experimental program sponsored by the Air Force Flight Dynamics Laboratory is currently in progress to determine the internal and installed performance characteristics of five different thrust vectoring/reversing non-axisymmetric nozzle concepts for tactical fighter aircraft applications. Internal performance characteristics for the five non-axisymmetric nozzles and an advanced technology axisymmetric baseline nozzle were determined in static tests conducted in January 1977 at the NASA-Langley Research Center. The non-axisymmetric nozzle models were tested at thrust deflection angles of up to 30 degrees from horizontal at throat areas associated with both dry and afterburning power. In addition, dry power reverse thrust geometries were tested for three of the concepts. The best designs demonstrated internal performance levels essentially equivalent to the baseline axisymmetric nozzle at unvectored conditions. The best designs also gave minimum performance losses due to vectoring, and reverse thrust levels up to 50% of maximum dry power forward thrust. The installed performance characteristics will be established based on wind tunnel testing to be conducted at Arnold Engineering Development Center in the fall of 1977.

  7. Quantitative Imaging of Young's Modulus of Soft Tissues from Ultrasound Water Jet Indentation: A Finite Element Study

    PubMed Central

    Lu, Min-Hua; Mao, Rui; Lu, Yin; Liu, Zheng; Wang, Tian-Fu; Chen, Si-Ping

    2012-01-01

    Indentation testing is a widely used approach to evaluate mechanical characteristics of soft tissues quantitatively. Young's modulus of soft tissue can be calculated from the force-deformation data with known tissue thickness and Poisson's ratio using Hayes' equation. Our group previously developed a noncontact indentation system using a water jet as a soft indenter as well as the coupling medium for the propagation of high-frequency ultrasound. The novel system has shown its ability to detect the early degeneration of articular cartilage. However, there is still lack of a quantitative method to extract the intrinsic mechanical properties of soft tissue from water jet indentation. The purpose of this study is to investigate the relationship between the loading-unloading curves and the mechanical properties of soft tissues to provide an imaging technique of tissue mechanical properties. A 3D finite element model of water jet indentation was developed with consideration of finite deformation effect. An improved Hayes' equation has been derived by introducing a new scaling factor which is dependent on Poisson's ratios v, aspect ratio a/h (the radius of the indenter/the thickness of the test tissue), and deformation ratio d/h. With this model, the Young's modulus of soft tissue can be quantitatively evaluated and imaged with the error no more than 2%. PMID:22927890

  8. Magnetization reversal mechanism and coercivity enhancement in three-dimensional granular Nd-Fe-B magnets studied by micromagnetic simulations

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Hyeok; Choe, Jinhyeok; Hwang, Shinwon; Kim, Sang-Koog

    2017-08-01

    We studied the mechanism of magnetization reversals and coercivity enhancements in three-dimensional (3D) granular Nd-Fe-B permanent magnets using finite-element micromagnetic simulations. The magnetization reversals in the hard magnets consisting of hard-phase grains separated by relatively soft-phase grain boundaries were analyzed with reference to the simulation results for the magnetic field-dependent distributions of the local magnetizations. The saturation magnetization of the grain-boundary phase plays a crucial role in the transition between nucleation- and domain-wall-propagation-controlled reversal processes. The smaller the saturation magnetization of the grain-boundary phase is, the more preferable is the nucleation-controlled process, which results in a larger coercivity. The exchange stiffness of the grain-boundary phase determines the preferred paths of domain-wall propagations, whether inward into grains or along the grain boundaries for relatively small and large exchange stiffness, respectively. However, the exchange stiffness of the grain-boundary phase alone does not significantly contribute to coercivity enhancement in cases where the size of hard-phase grains is much greater than the exchange length. This work paves the way for the design of high-performance hard magnets of large coercivity and maximum-energy-product values.

  9. Reverse micelle-loaded lipid nano-emulsions: new technology for nano-encapsulation of hydrophilic materials.

    PubMed

    Anton, Nicolas; Mojzisova, Halina; Porcher, Emilien; Benoit, Jean-Pierre; Saulnier, Patrick

    2010-10-15

    This study presents novel, recently patented technology for encapsulating hydrophilic species in lipid nano-emulsions. The method is based on the phase-inversion temperature method (the so-called PIT method), which follows a low-energy and solvent-free process. The nano-emulsions formed are stable for months, and exhibit droplet sizes ranging from 10 to 200 nm. Hydrophilic model molecules of fluorescein sodium salt are encapsulated in the oily core of these nano-emulsion droplets through their solubilisation in the reverse micellar system. As a result, original, multi-scaled nano-objects are generated with a 'hydrophilic molecule in a reverse-micelles-in-oil-in-water' structure. Once fluorescein has been encapsulated it remains stable, for thermodynamic reasons, and the encapsulation yields can reach 90%. The reason why such complex objects can be formed is due to the soft method used (PIT method) which allows the conservation of the structure of the reverse micelles throughout the formulation process, up to their entrapment in the nano-emulsion droplets. In this study, we focus the investigation on the process itself, revealing its potential and limits. Since the formulation of nanocarriers for the encapsulation of hydrophilic substances still remains a challenge, this study may constitute a significant advance in this field. Copyright 2010 Elsevier B.V. All rights reserved.

  10. Reversing the conventional leather processing sequence for cleaner leather production.

    PubMed

    Saravanabhavan, Subramani; Thanikaivelan, Palanisamy; Rao, Jonnalagadda Raghava; Nair, Balachandran Unni; Ramasami, Thirumalachari

    2006-02-01

    Conventional leather processing generally involves a combination of single and multistep processes that employs as well as expels various biological, inorganic, and organic materials. It involves nearly 14-15 steps and discharges a huge amount of pollutants. This is primarily due to the fact that conventional leather processing employs a "do-undo" process logic. In this study, the conventional leather processing steps have been reversed to overcome the problems associated with the conventional method. The charges of the skin matrix and of the chemicals and pH profiles of the process have been judiciously used for reversing the process steps. This reversed process eventually avoids several acidification and basification/neutralization steps used in conventional leather processing. The developed process has been validated through various analyses such as chromium content, shrinkage temperature, softness measurements, scanning electron microscopy, and physical testing of the leathers. Further, the performance of the leathers is shown to be on par with conventionally processed leathers through bulk property evaluation. The process enjoys a significant reduction in COD and TS by 53 and 79%, respectively. Water consumption and discharge is reduced by 65 and 64%, respectively. Also, the process benefits from significant reduction in chemicals, time, power, and cost compared to the conventional process.

  11. Techniques for Achieving Zero Stress in Thin Films of Iridium, Chromium, and Nickel

    NASA Technical Reports Server (NTRS)

    Broadway, David M.; O'Dell, Stephen L.; Ramsey, Brian D.; Weimer, Jeffrey

    2015-01-01

    We examine techniques for achieving zero intrinsic stress in thin films of iridium, chromium, and nickel deposited by magnetron sputter deposition. The intrinsic stress is further correlated to the microstructural features and physical properties such as surface roughness and optical density at a scale appropriate to soft X-ray wavelengths. The examination of the stress in these materials is motivated by efforts to advance the optical performance of light-weight X-ray space telescopes into the regime of sub-arcsecond resolution through various deposition techniques that rely on control of the film stress to values within 10-100 MPa. A characteristic feature of the intrinsic stress behavior in chromium and nickel is their sensitivity to the magnitude and sign of the intrinsic stress with argon gas pressure and deposition rate, including the existence of a critical argon process pressure that results in zero film stress which scales linearly with the atomic mass of the sputtered species. While the effect of stress reversal with argon pressure has been previously reported by Hoffman and others for nickel and chromium, we report this effect for iridium. In addition to stress reversal, we identify zero stress in the optical functioning iridium layer shortly after island coalescence for low process pressures at a film thickness of approximately 35nm. The measurement of the low values of stress during deposition was achieved with the aid of a sensitive in-situ instrument capable of a minimum detectable level of stress, assuming a 35nm thick film, in the range of 0.40-6.0 MPa for <111> oriented crystalline silicon substrate thicknesses of 70-280 microns, respectively.

  12. Soft qualities in healthcare. Method and tools for soft qualities design in hospitals' built environments.

    PubMed

    Capolongo, S; Bellini, E; Nachiero, D; Rebecchi, A; Buffoli, M

    2014-01-01

    The design of hospital environments is determined by functional requirements and technical regulations, as well as numerous protocols, which define the structure and system characteristics that such environments need to achieve. In order to improve people's well-being and the quality of their experience within public hospitals, design elements (soft qualities) are added to those 'necessary' features. The aim of this research has been to experiment a new design process and also to create health care spaces with high environmental quality and capable to meet users' emotional and perceptual needs. Such needs were investigated with the help of qualitative research tools and the design criteria for one of these soft qualities - colour - were subsequently defined on the basis of the findings. The colour scheme design for the new San Paolo Hospital Emergency Department in Milan was used as case study. Focus groups were fundamental in defining the project's goals and criteria. The issues raised have led to believe that the proper procedure is not the mere consultation of the users in order to define the goals: users should rather be involved in the whole design process and become co-agents of the choices that determine the environment characteristics, so as to meet the quality requirements identified by the users themselves. The case study has shown the possibility of developing a designing methodology made by three steps (or operational tools) in which users' groups are involved in the choices, loading to plan the environments where compliance with expectations is already implied and verified by means of the process itself. Thus, the method leads to the creation of soft qualities in Healthcare.

  13. Reversing storm hotspots on sandy beaches: Spatial and temporal characteristics

    USGS Publications Warehouse

    List, J.H.; Farris, A.S.; Sullivan, C.

    2006-01-01

    Coastal erosion hotspots are defined as sections of coast that exhibit significantly higher rates of erosion than adjacent areas. This paper describes the spatial and temporal characteristics of a recently identified type of coastal erosion hotspot, which forms in response to storms on uninterrupted sandy coasts largely free from human intervention. These are referred to here as reversing storm hotspots because the erosion is reversed by accretion of a similar magnitude to the storm-induced erosion. The accretion occurs within a few days or weeks of fair weather after the storm. Reversing storm hotspots observed here, on two US east coast beaches, have a longshore length averaging 3.86 km, a cross-shore excursion (magnitude of erosion or accretion) averaging 15.4 m, and a time scale of days to weeks associated with individual storm events. These spatial and temporal scales clearly distinguish reversing storm hotspots from previously described forms of longshore variability in erosion, including those attributed to several types of shoreline undulations and hotspots associated with long-term shoreline change. 

  14. Flare onsets in hard and soft X-rays. [magnetic energy conversion in sun

    NASA Technical Reports Server (NTRS)

    Machado, Marcos E.; Orwig, Larry E.; Antonucci, Ester

    1986-01-01

    It is shown that the onset of solar flares, within about 2 min or less before the impulsive peaks, is characterized by an increase in high-energy emission at E less than 100 keV, and strong broadening of soft X-ray lines characteristic of the 10-million-K plasma already present at this stage. The observations are interpreted in terms of the early signature of energy release, during a phase preceding the instability that leads to strong particle acceleration.

  15. The development and test of multi-anode microchannel array detector systems. 2: Soft X-ray detectors

    NASA Technical Reports Server (NTRS)

    Timothy, J. G.

    1983-01-01

    The techniques and procedures for producing very-large-format pulse-counting array detector systems for use in forthcoming high-energy astrophysics facilities were defined, and the structures and performance characteristics of high-sensitivity photocathodes for use at soft X-ray wavelengths between 100 and 1 A were determined. The progress made to date in each of these areas are described and the tasks that will be undertaken when the program is continued are summarized.

  16. Precursor directed synthesis--"molecular" mechanisms in the Soft Chemistry approaches and their use for template-free synthesis of metal, metal oxide and metal chalcogenide nanoparticles and nanostructures.

    PubMed

    Seisenbaeva, Gulaim A; Kessler, Vadim G

    2014-06-21

    This review provides an insight into the common reaction mechanisms in Soft Chemistry processes involved in nucleation, growth and aggregation of metal, metal oxide and chalcogenide nanoparticles starting from metal-organic precursors such as metal alkoxides, beta-diketonates, carboxylates and their chalcogene analogues and demonstrates how mastering the precursor chemistry permits us to control the chemical and phase composition, crystallinity, morphology, porosity and surface characteristics of produced nanomaterials.

  17. Numerical modeling of reverse recovery characteristic in silicon pin diodes

    NASA Astrophysics Data System (ADS)

    Yamashita, Yusuke; Tadano, Hiroshi

    2018-07-01

    A new numerical reverse recovery model of silicon pin diode is proposed by the approximation of the reverse recovery waveform as a simple shape. This is the first model to calculate the reverse recovery characteristics using numerical equations without adjusted by fitting equations and fitting parameters. In order to verify the validity and the accuracy of the numerical model, the calculation result from the model is verified through the device simulation result. In 1980, he joined Toyota Central R&D Labs, Inc., where he was involved in the research and development of power devices such as SIT, IGBT, diodes and power MOSFETs. Since 2013 he has been a professor at the Graduate School of Pure and Applied Science, University of Tsukuba, Tsukuba, Japan. His current research interest is high-efficiency power conversion circuits for electric vehicles using advanced power devices.

  18. Experimental Research on Creep Characteristics of Nansha Soft Soil

    PubMed Central

    Luo, Qingzi; Chen, Xiaoping

    2014-01-01

    A series of tests were performed to investigate the creep characteristics of soil in interactive marine and terrestrial deposit of Pearl River Delta. The secondary consolidation test results show that the influence of consolidation pressure on coefficient of secondary consolidation is conditional, which is decided by the consolidation state. The ratio of coefficient of secondary consolidation and coefficient of compressibility C a/C c is almost a constant, and the value is 0.03. In the shear-box test, the direct sheer creep failure of soil is mainly controlled by shear stress rather than the accumulation of shear strain. The triaxial creep features are closely associated with the drainage conditions, and consolidation can weaken the effect of creep. When the soft soil has triaxial creep damage, the strain rate will increase sharply. PMID:24526925

  19. Experimental research on creep characteristics of Nansha soft soil.

    PubMed

    Luo, Qingzi; Chen, Xiaoping

    2014-01-01

    A series of tests were performed to investigate the creep characteristics of soil in interactive marine and terrestrial deposit of Pearl River Delta. The secondary consolidation test results show that the influence of consolidation pressure on coefficient of secondary consolidation is conditional, which is decided by the consolidation state. The ratio of coefficient of secondary consolidation and coefficient of compressibility (Ca/Cc) is almost a constant, and the value is 0.03. In the shear-box test, the direct sheer creep failure of soil is mainly controlled by shear stress rather than the accumulation of shear strain. The triaxial creep features are closely associated with the drainage conditions, and consolidation can weaken the effect of creep. When the soft soil has triaxial creep damage, the strain rate will increase sharply.

  20. Solid tumors.

    PubMed

    Richardson, R C

    1985-05-01

    Soft-tissue tumors are similar in their behavior. Benign tumors can be easily resected in most cases, whereas malignant tumors are relentless in their locally invasive characteristics. A clear understanding of the constraints of the pathologist in reaching a confirmed diagnosis and a logical plan utilizing surgery as the major modality of therapy are necessary for successful management of these tumors. It appears that radiation combined with hyperthermia is beginning to play a significant role in the local control of soft-tissue sarcomas and that single or multi-agent chemotherapy may be of benefit in treatment of nonresectable or metastatic soft-tissue sarcomas. For the immediate future, surgery remains the only nonexperimental modality of therapy, but the rapid advances in the other therapy methods are encouraging.

  1. Rational design of the exchange-spring permanent magnet.

    PubMed

    Jiang, J S; Bader, S D

    2014-02-12

    The development of the optimal exchange-spring permanent magnet balances exchange hardening, magnetization enhancement, and the feasibility of scalable fabrication. These requirements can be met with a rational design of the microstructural characteristics. The magnetization processes in several model exchange-spring structures with different geometries have been analyzed with both micromagnetic simulations and nucleation theory. The multilayer geometry and the soft-cylinders-in-hard-matrix geometry have the highest achievable figure of merit (BH)max, while the soft-spheres-in-hard-matrix geometry has the lowest upper limit for (BH)max. The cylindrical geometry permits the soft phase to be larger and does not require strict size control. Exchange-spring permanent magnets based on the cylindrical geometry may be amenable to scaled-up fabrication.

  2. Soft X-Ray Emissions from Planets and Moons

    NASA Technical Reports Server (NTRS)

    Bhardwaj, A.; Gladstone, G. R.; Elsner, R. F.; Waite, J. H., Jr.; Grodent, D.; Cravens, T. E.; Howell, R. R.; Metzger, A. E.; Ostgaard, N.; Maurellis, A.; hide

    2002-01-01

    A wide variety of solar system planetary bodies are now known to radiate in the soft x-ray energy (<5 keV) regime. These include planets (Earth, Jupiter, Venus, Saturn): bodies having thick atmosphere and with/without intrinsic magnetic field; planetary satellites (Moon, Io, Europa, Ganymede): bodies with no/thin atmosphere; and comets and Io plasma torus: bodies having extended tenuous atmosphere. Several different mechanisms have been proposed to explain the generation of soft x-rays from these objects. whereas in the hard x-ray energy range (>10 keV) x-rays mainly result from electron bremsstrahlung process. In this paper we present a brief review of the x-ray observations on each of the planetary bodies and discuss their characteristics and proposed source mechanisms.

  3. Soft Rot of Rhizopus oryzae as a Postharvest Pathogen of Banana Fruit in Korea

    PubMed Central

    Ryu, Jae-San; Chi, Tran Thi Phuong; Shen, Shun-Shan; Choi, Okhee

    2012-01-01

    Soft rot on banana fruit caused by Rhizopus oryzae was identified for the first time in Korea. Colonies were white to light brown and formed numerous sporangiospores. Optimum temperature for mycelial growth was 30℃. Sporangia were globose and 30~200 µm. Sporangiophores were usually straight, 8~20 µm, and rhizoids usually in groups of 3~5. Columella were globose to sub-globose and 90~110 µm. Sporangiospores were sub-globose or oval and 4~10 µm. Based on its mycological characteristics, molecular analysis, and pathogenicity to host plants, this fungus was identified as Rhizopus oryzae Went & Prisen Geerligs. This is the first report of soft rot on banana caused by Rhizopus oryzae in Korea. PMID:23115518

  4. ANISOTROPY DETERMINATIONS IN EXCHANGE SPRING MAGNETS.

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

    LEWIS,L.H.; HARLAND,C.L.

    2002-08-18

    Ferromagnetic nanocomposites, or ''exchange spring'' magnets, possess a nanoscaled microstructure that allows intergrain magnetic exchange forces to couple the constituent grains and alter the system's effective magnetic anisotropies. While the effects of the anisotropy alterations are clearly seen in macroscopic magnetic measurement, it is extremely difficult to determine the detailed effects of the system's exchange coupling, such as the interphase exchange length, the inherent domain wall widths or the effective anisotropies of the system. Clarification of these materials parameters may be obtained from the ''micromagnetic'' phenomenological model, where the assumption of magnetic reversal initiating in the magnetically-soft regions of themore » exchange-spring maqet is explicitly included. This approach differs from that typically applied by other researchers and allows a quantitative estimate of the effective anisotropies of an exchange spring system. Hysteresis loops measured on well-characterized nanocomposite alloys based on the composition Nd{sub 2}Fe{sub 14}B + {alpha}-Fe at temperatures above the spin reorientation temperature were analyzed within the framework of the micromagnetic phenomenological model. Preliminary results indicate that the effective anisotropy constant in the material is intermediate to that of bulk {alpha}-Fe and bulk Nd{sub 2}Fe{sub 14}B and increases with decreasing temperature. These results strongly support the idea that magnetic reversal in nanocomposite systems initiates in the lower-anisotropy regions of the system, and that the soft-phase regions become exchange-hardened by virtue of their proximity to the magnetically-hard regions.« less

  5. Role of Soft Computing Approaches in HealthCare Domain: A Mini Review.

    PubMed

    Gambhir, Shalini; Malik, Sanjay Kumar; Kumar, Yugal

    2016-12-01

    In the present era, soft computing approaches play a vital role in solving the different kinds of problems and provide promising solutions. Due to popularity of soft computing approaches, these approaches have also been applied in healthcare data for effectively diagnosing the diseases and obtaining better results in comparison to traditional approaches. Soft computing approaches have the ability to adapt itself according to problem domain. Another aspect is a good balance between exploration and exploitation processes. These aspects make soft computing approaches more powerful, reliable and efficient. The above mentioned characteristics make the soft computing approaches more suitable and competent for health care data. The first objective of this review paper is to identify the various soft computing approaches which are used for diagnosing and predicting the diseases. Second objective is to identify various diseases for which these approaches are applied. Third objective is to categories the soft computing approaches for clinical support system. In literature, it is found that large number of soft computing approaches have been applied for effectively diagnosing and predicting the diseases from healthcare data. Some of these are particle swarm optimization, genetic algorithm, artificial neural network, support vector machine etc. A detailed discussion on these approaches are presented in literature section. This work summarizes various soft computing approaches used in healthcare domain in last one decade. These approaches are categorized in five different categories based on the methodology, these are classification model based system, expert system, fuzzy and neuro fuzzy system, rule based system and case based system. Lot of techniques are discussed in above mentioned categories and all discussed techniques are summarized in the form of tables also. This work also focuses on accuracy rate of soft computing technique and tabular information is provided for each category including author details, technique, disease and utility/accuracy.

  6. A novel low temperature soft reflow process for the fabrication of deep-submicron (<0.35 μm) T-gate pseudomorphic high electron mobility transistor structures

    NASA Astrophysics Data System (ADS)

    Ian, Ka Wa; Exarchos, Michael; Missous, Mohamed

    2013-02-01

    We report a new and simple low temperature soft reflow process using solvent vapour. The combination of this soft reflow and conventional i-line lithography enables low cost, highly efficient fabrication at the deep-submicron scale. Compared to the conventional thermal reflow process, the key benefits of the new soft reflow process are its low temperature operation (<50 °C), greater shrinkage of the structure size (up to 75%) and better controllability. Gate openings reflowed from 1 μm to 250 nm have been routinely and reproducibly achieved by utilizing the saturation characteristics of the process. The feasibility of this soft reflow process is demonstrated in the fabrication of a 350 nm T-gate pseudomorphic high electron mobility transistor. By shrinking the gate length by a factor of three (from a 1 μm initial opening), the output current is improved by 60% (500 mA mm-1 from 300 mA mm-1) and fT and fMAX are increased to 70 GHz (from 20 GHz) and 120 GHz (from 40 GHz) respectively. The proposed soft reflow could potentially be applied on other compatible substrates such as polymer based material for organic or thin film devices, potentially leading to many new possible applications.

  7. Modelling hard and soft states of Cygnus X-1 with propagating mass accretion rate fluctuations

    NASA Astrophysics Data System (ADS)

    Rapisarda, S.; Ingram, A.; van der Klis, M.

    2017-12-01

    We present a timing analysis of three Rossi X-ray Timing Explorer observations of the black hole binary Cygnus X-1 with the propagating mass accretion rate fluctuations model PROPFLUC. The model simultaneously predicts power spectra, time lags and coherence of the variability as a function of energy. The observations cover the soft and hard states of the source, and the transition between the two. We find good agreement between model predictions and data in the hard and soft states. Our analysis suggests that in the soft state the fluctuations propagate in an optically thin hot flow extending up to large radii above and below a stable optically thick disc. In the hard state, our results are consistent with a truncated disc geometry, where the hot flow extends radially inside the inner radius of the disc. In the transition from soft to hard state, the characteristics of the rapid variability are too complex to be successfully described with PROPFLUC. The surface density profile of the hot flow predicted by our model and the lack of quasi-periodic oscillations in the soft and hard states suggest that the spin of the black hole is aligned with the inner accretion disc and therefore probably with the rotational axis of the binary system.

  8. Effect of tissue composition on dose distribution in brachytherapy with various photon emitting sources

    PubMed Central

    Ghorbani, Mahdi; Salahshour, Fateme; Haghparast, Abbas; Knaup, Courtney

    2014-01-01

    Purpose The aim of this study is to compare the dose in various soft tissues in brachytherapy with photon emitting sources. Material and methods 103Pd, 125I, 169Yb, 192Ir brachytherapy sources were simulated with MCNPX Monte Carlo code, and their dose rate constant and radial dose function were compared with the published data. A spherical phantom with 50 cm radius was simulated and the dose at various radial distances in adipose tissue, breast tissue, 4-component soft tissue, brain (grey/white matter), muscle (skeletal), lung tissue, blood (whole), 9-component soft tissue, and water were calculated. The absolute dose and relative dose difference with respect to 9-component soft tissue was obtained for various materials, sources, and distances. Results There was good agreement between the dosimetric parameters of the sources and the published data. Adipose tissue, breast tissue, 4-component soft tissue, and water showed the greatest difference in dose relative to the dose to the 9-component soft tissue. The other soft tissues showed lower dose differences. The dose difference was also higher for 103Pd source than for 125I, 169Yb, and 192Ir sources. Furthermore, greater distances from the source had higher relative dose differences and the effect can be justified due to the change in photon spectrum (softening or hardening) as photons traverse the phantom material. Conclusions The ignorance of soft tissue characteristics (density, composition, etc.) by treatment planning systems incorporates a significant error in dose delivery to the patient in brachytherapy with photon sources. The error depends on the type of soft tissue, brachytherapy source, as well as the distance from the source. PMID:24790623

  9. Change of external sexual characteristics during consecutive moults in Crangon crangon L

    NASA Astrophysics Data System (ADS)

    Schatte, Jessica; Saborowski, Reinhard

    2006-03-01

    Adult males of the North Sea shrimp, Crangon crangon, were maintained for 8 months in the laboratory under natural temperature and light cycles. Successive moults were analysed for morphological changes. Out of the 70 shrimps, one male performed morphological sex reversal by reducing the male characteristics and developing female characteristics. The morphological changes including the loss of the appendix masculina appeared within a single moult cycle. This observation proves that C. crangon males may be capable of changing sex. The low number of sex reversals indicates that C. crangon is a facultative rather than an obligate protandric hermaphrodite.

  10. Multiresponsive Kinematics and Robotics of Surface-Patterned Polymer Film.

    PubMed

    Liang, Shumin; Qiu, Xiaxin; Yuan, Jun; Huang, Wei; Du, Xuemin; Zhang, Lidong

    2018-06-06

    Soft robots, sensors, and energy harvesters require materials that are capable of converting external stimuli to visible deformations, especially when shape-programmable deformations are desired. Herein, we develop a polymer film that can reversibly respond to humidity, heating, and acetone vapors with the generation of shape-programmable large deformations. Poly(vinylidene fluoride) film, capable of providing acetone responsiveness, is designed with microchannel patterns created on its one side by using templates, and the microchannels-patterned side is then treated with hygroscopic 3-aminopropyltriethoxysilane (APTES) to give humidity/heating-responsive elements. The APTES-modified microchannels lead to anisotropic flexural modulus and hygroscopicity in the film, resulting in the shape-programmed kinematics depending on the orientations of surface microchannels. As the microchannels align at oblique/right angles with respect to the long axis of the film strips, the coiling/curling motions can be generated in response to the stimuli, and the better motion performances are found in humidity- and heating-driven systems. This material utilized in self-adaptive soft robots exhibits prominent toughness, powerful strength, and long endurance for converting humidity and heat to mechanical works including transportation of lightweight objects, automatic sensing cap, and mimicking crawling in nature. We thus believe that this material with shape-programmable multisensing capability might be suitable for soft machines and robotics.

  11. Advanced hole patterning technology using soft spacer materials (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Park, Jong Keun; Hustad, Phillip D.; Aqad, Emad; Valeri, David; Wagner, Mike D.; Li, Mingqi

    2017-03-01

    A continuing goal in integrated circuit industry is to increase density of features within patterned masks. One pathway being used by the device manufacturers for patterning beyond the 80nm pitch limitation of 193 immersion lithography is the self-aligned spacer double patterning (SADP). Two orthogonal line space patterns with subsequent SADP can be used for contact holes multiplication. However, a combination of two immersion exposures, two spacer deposition processes, and two etch processes to reach the desired dimensions makes this process expensive and complicated. One alternative technique for contact hole multiplication is the use of an array of pillar patterns. Pillars, imaged with 193 immersion photolithography, can be uniformly deposited with spacer materials until a hole is formed in the center of 4 pillars. Selective removal of the pillar core gives a reversal of phases, a contact hole where there was once a pillar. However, the highly conformal nature of conventional spacer materials causes a problem with this application. The new holes, formed between 4 pillars, by this method have a tendency to be imperfect and not circular. To improve the contact hole circularity, this paper presents the use of both conventional spacer material and soft spacer materials. Application of soft spacer materials can be achieved by an existing coating track without additional cost burden to the device manufacturers.

  12. Past matrix stiffness primes epithelial cells and regulates their future collective migration through a mechanical memory.

    PubMed

    Nasrollahi, Samila; Walter, Christopher; Loza, Andrew J; Schimizzi, Gregory V; Longmore, Gregory D; Pathak, Amit

    2017-11-01

    During morphogenesis and cancer metastasis, grouped cells migrate through tissues of dissimilar stiffness. Although the influence of matrix stiffness on cellular mechanosensitivity and motility are well-recognized, it remains unknown whether these matrix-dependent cellular features persist after cells move to a new microenvironment. Here, we interrogate whether priming of epithelial cells by a given matrix stiffness influences their future collective migration on a different matrix - a property we refer to as the 'mechanical memory' of migratory cells. To prime cells on a defined matrix and track their collective migration onto an adjoining secondary matrix of dissimilar stiffness, we develop a modular polyacrylamide substrate through step-by-step polymerization of different PA compositions. We report that epithelial cells primed on a stiff matrix migrate faster, display higher actomyosin expression, form larger focal adhesions, and retain nuclear YAP even after arriving onto a soft secondary matrix, as compared to their control behavior on a homogeneously soft matrix. Priming on a soft ECM causes a reverse effect. The depletion of YAP dramatically reduces this memory-dependent migration. Our results present a previously unidentified regulation of mechanosensitive collective cell migration by past matrix stiffness, in which mechanical memory depends on YAP activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Development and fabrication of improved Schottky power diodes

    NASA Technical Reports Server (NTRS)

    Cordes, L. F.; Garfinkel, M.; Taft, E. A.

    1975-01-01

    Reproducible methods for the fabrication of silicon Schottky diodes have been developed for tungsten, aluminum, conventional platinum silicide, and low temperature platinum silicide. Barrier heights and barrier lowering under reverse bias have been measured, permitting the accurate prediction of forward and reverse diode characteristics. Processing procedures have been developed that permit the fabrication of large area (about 1 sq cm) mesageometry power Schottky diodes with forward and reverse characteristics that approach theoretical values. A theoretical analysis of the operation of bridge rectifier circuits has been performed, which indicates the ranges of frequency and voltage for which Schottky rectifiers are preferred to p-n junctions. Power Schottky rectifiers have been fabricated and tested for voltage ratings up to 140 volts.

  14. The potential of mild testicular heating as a safe, effective and reversible contraceptive method for men.

    PubMed

    Mieusset, R; Bujan, L

    1994-08-01

    A preliminary assessment of the contraceptive efficacy of a daily mild increase (1-2 degrees C) in testicular temperature during waking hours is reported in nine couples using two techniques of non-surgical fixation of the testes close to the inguinal canal. With technique 1, immobilization was achieved by passing the penis and the empty scrotum through a hole made in close-fitting underwear; there was one pregnancy, from a man who stopped the heating after 7 weeks, for 42 cycles of exposure in three couples. With technique 2, immobilization was achieved by adding a ring of soft material surrounding the hole in the underwear; there was no pregnancy for 117 cycles of exposure in six couples. Reversibility and safety were assessed. These preliminary results suggest that a daily mild increase in testicular temperature could be a potential contraceptive method for men.

  15. Long-Term Cryogenic Propellant Storage on Mars with Hercules Propellant Storage Facility

    NASA Technical Reports Server (NTRS)

    Liu, Gavin

    2017-01-01

    This report details the process and results of roughly sizing the steady state, zero boil-off thermal and power parameters of the Hercules Propellant Storage Facility. For power analysis, isothermal and isobaric common bulkhead tank scenarios are considered. An estimated minimum power requirement of 8.3 kW for the Reverse Turbo-Brayton Cryocooler is calculated. Heat rejection concerns in soft vacuum Mars atmosphere are noted and potential solutions are proposed. Choice of coolant for liquid propellant conditioning and issues with current proposed cryocooler cycle are addressed; recommendations are made, e.g. adding a Joule-Thomson expansion valve after the Reverse Turbo-Brayton turbine in order to have two-phase, isothermal heat exchange through the Broad Area Cooling system. Issues with cross-country transfer lines from propellant storage to flight vehicle are briefly discussed: traditional vacuum jacketed lines are implausible, and Mars insulation needs to be developed.

  16. Three-dimensional printing of complex biological structures by freeform reversible embedding of suspended hydrogels

    PubMed Central

    Hinton, Thomas J.; Jallerat, Quentin; Palchesko, Rachelle N.; Park, Joon Hyung; Grodzicki, Martin S.; Shue, Hao-Jan; Ramadan, Mohamed H.; Hudson, Andrew R.; Feinberg, Adam W.

    2015-01-01

    We demonstrate the additive manufacturing of complex three-dimensional (3D) biological structures using soft protein and polysaccharide hydrogels that are challenging or impossible to create using traditional fabrication approaches. These structures are built by embedding the printed hydrogel within a secondary hydrogel that serves as a temporary, thermoreversible, and biocompatible support. This process, termed freeform reversible embedding of suspended hydrogels, enables 3D printing of hydrated materials with an elastic modulus <500 kPa including alginate, collagen, and fibrin. Computer-aided design models of 3D optical, computed tomography, and magnetic resonance imaging data were 3D printed at a resolution of ~200 μm and at low cost by leveraging open-source hardware and software tools. Proof-of-concept structures based on femurs, branched coronary arteries, trabeculated embryonic hearts, and human brains were mechanically robust and recreated complex 3D internal and external anatomical architectures. PMID:26601312

  17. A magnetostatic-coupling based remote query sensor for environmental monitoring

    NASA Technical Reports Server (NTRS)

    Grimes, C. A.; Stoyanov, P. G.; Liu, Y.; Tong, C.; Ong, K. G.; Loiselle, K.; Shaw, M.; Doherty, S. A.; Seitz, W. R.

    1999-01-01

    A new type of in situ, remotely monitored magnetism-based sensor is presented that is comprised of an array of magnetically soft, magnetostatically-coupled ferromagnetic thin-film elements or particles combined with a chemically responsive material that swells or shrinks in response to the analyte of interest. As the chemically responsive material changes size the distance between the ferromagnetic elements changes, altering the inter-element magnetostatic coupling. This in turn changes the coercive force of the sensor, the amplitude of the voltage spikes detected in nearby pick-up coils upon magnetization reversal and the number of higher-order harmonics generated by the flux reversal. Since the sensor is monitored through changes in magnetic flux, no physical connections such as wires or cables are needed to obtain sensor information, nor is line of sight alignment required as with laser telemetry; the sensors can be detected from within sealed, opaque or thin metallic enclosures.

  18. An immortalized goat mammary epithelial cell line induced with human telomerase reverse transcriptase (hTERT) gene transfer.

    PubMed

    He, Y L; Wu, Y H; He, X N; Liu, F J; He, X Y; Zhang, Y

    2009-06-01

    Although mammary epithelial cell lines can provide a rapid and reliable indicator of gene expression efficiency of transgenic animals, their short lifespan greatly limits this application. To provide stable and long lifespan cells, goat mammary epithelial cells (GMECs) were transduced with pLNCX2-hTERT by retrovirus-mediated gene transfer. Transduced GMECs were evaluated by reverse transcriptase polymerase chain reaction (RT-PCR), proliferation assays, karyotype analysis, telomerase activity assay, western blotting, soft agar assay, and injection into nude mice. Non-transduced GMECs were used as a control. The hTERT-GMECs had higher telomerase activity and extended proliferative lifespan compared to non-transfected GMECs; even after Passage 50, hTERT-GMECs had a near diploid complement of chromosomes. Furthermore, they did not gain the anchorage-independent growth property and were not associated with a malignant phenotype in vitro or in vivo.

  19. Reversible patterning of spherical shells through constrained buckling

    NASA Astrophysics Data System (ADS)

    Marthelot, J.; Brun, P.-T.; Jiménez, F. López; Reis, P. M.

    2017-07-01

    Recent advances in active soft structures envision the large deformations resulting from mechanical instabilities as routes for functional shape morphing. Numerous such examples exist for filamentary and plate systems. However, examples with double-curved shells are rarer, with progress hampered by challenges in fabrication and the complexities involved in analyzing their underlying geometrical nonlinearities. We show that on-demand patterning of hemispherical shells can be achieved through constrained buckling. Their postbuckling response is stabilized by an inner rigid mandrel. Through a combination of experiments, simulations, and scaling analyses, our investigation focuses on the nucleation and evolution of the buckling patterns into a reticulated network of sharp ridges. The geometry of the system, namely, the shell radius and the gap between the shell and the mandrel, is found to be the primary ingredient to set the surface morphology. This prominence of geometry suggests a robust, scalable, and tunable mechanism for reversible shape morphing of elastic shells.

  20. Comparison of soft-tissue orbital morphometry in attractive and normal Italian subjects.

    PubMed

    Sforza, Chiarella; Dolci, Claudia; Grandi, Gaia; Tartaglia, Gianluca M; Laino, Alberto; Ferrario, Virgilio F

    2015-01-01

    To identify esthetic characteristics of the orbital soft tissues of attractive Italian adult women and men. Three-dimensional computerized digitizers were used to collect the coordinates of facial landmarks in 199 healthy, normal subjects aged 18 to 30 years (71 women, 128 men; mean age, 22 years) and in 126 coetaneous attractive subjects (92 women, 34 men; mean age, 20 years) selected during beauty competitions. From the landmarks, six linear distances, two ratios, six angles, and two areas were calculated. Attractive subjects were compared with normal ones by computing z-scores. Intercanthal width was reduced while eye fissure lengths were increased in both genders. Orbital heights (os-or) were increased only in attractive women, with a significant gender-related difference. The inclinations of the eye fissure were increased in attractive subjects, while the inclinations of the orbit were reduced. For several of the analyzed measurements, similar patterns of z-scores were observed for attractive men and women (r  =  .883). Attractive women and men had several specific esthetic characteristics in their orbital soft tissues; esthetic reference values can be used to determine optimal goals in surgical treatment.

  1. Suppression of fixed pattern noise for infrared image system

    NASA Astrophysics Data System (ADS)

    Park, Changhan; Han, Jungsoo; Bae, Kyung-Hoon

    2008-04-01

    In this paper, we propose suppression of fixed pattern noise (FPN) and compensation of soft defect for improvement of object tracking in cooled staring infrared focal plane array (IRFPA) imaging system. FPN appears an observable image which applies to non-uniformity compensation (NUC) by temperature. Soft defect appears glittering black and white point by characteristics of non-uniformity for IR detector by time. This problem is very important because it happen serious problem for object tracking as well as degradation for image quality. Signal processing architecture in cooled staring IRFPA imaging system consists of three tables: low, normal, high temperature for reference gain and offset values. Proposed method operates two offset tables for each table. This is method which operates six term of temperature on the whole. Proposed method of soft defect compensation consists of three stages: (1) separates sub-image for an image, (2) decides a motion distribution of object between each sub-image, (3) analyzes for statistical characteristic from each stationary fixed pixel. Based on experimental results, the proposed method shows an improved image which suppresses FPN by change of temperature distribution from an observational image in real-time.

  2. Soft-tissue rheumatism: diagnosis and treatment.

    PubMed

    Reveille, J D

    1997-01-27

    Soft tissue rheumatism is one of the most common and most misunderstood categories of disorders facing the primary care physician. Among the more common types are subacromial bursitis, epicondylitis, trochanteric bursitis, anserine bursitis, and fibromyalgia. The keys to the diagnosis of soft-tissue rheumatism are the history and, more importantly, the physical examination. Extensive laboratory testing and radiographs are not as helpful in evaluating patients with these complaints. Treatment consists of nonsteroidal anti-inflammatory drugs (NSAIDs) and nonnarcotic analgesics. Especially in patients with localized disorders, intralesional injections of corticosteroids are particularly effective and safe and should be part of the armamentarium of the primary care practitioner. Fibromyalgia is a particularly challenging form of nonarticular rheumatism. The clinical presentation is rather characteristic, with the patient typically being a woman 30-60 years of age who presents with diffuse somatic pain. Patients often give a history of sleep disturbance, may be depressed, and show characteristic tender areas, or trigger points. Laboratory findings are normal. Management includes reassurance, correction of the underlying sleep disturbance with low doses of a tricyclic antidepressant, treatment with muscle relaxants and nonnarcotic analgesics or NSAIDs, and an exercise program with a strong aerobic component.

  3. Controlling hazardous reactions during voltage reversal of high energy lithium cells

    NASA Technical Reports Server (NTRS)

    Domeniconi, M.

    1983-01-01

    The roll of general cell design characteristics in preventing hazardous reactions during voltage reversal of lithium cells is discussed. Anode limited versus cathode limited design and case positive versus case negative design are addressed.

  4. Soft Tissue Surgical Procedures for Optimizing Anterior Implant Esthetics

    PubMed Central

    Ioannou, Andreas L.; Kotsakis, Georgios A.; McHale, Michelle G.; Lareau, Donald E.; Hinrichs, James E.; Romanos, Georgios E.

    2015-01-01

    Implant dentistry has been established as a predictable treatment with excellent clinical success to replace missing or nonrestorable teeth. A successful esthetic implant reconstruction is predicated on two fundamental components: the reproduction of the natural tooth characteristics on the implant crown and the establishment of soft tissue housing that will simulate a healthy periodontium. In order for an implant to optimally rehabilitate esthetics, the peri-implant soft tissues must be preserved and/or augmented by means of periodontal surgical procedures. Clinicians who practice implant dentistry should strive to achieve an esthetically successful outcome beyond just osseointegration. Knowledge of a variety of available techniques and proper treatment planning enables the clinician to meet the ever-increasing esthetic demands as requested by patients. The purpose of this paper is to enhance the implant surgeon's rationale and techniques beyond that of simply placing a functional restoration in an edentulous site to a level whereby an implant-supported restoration is placed in reconstructed soft tissue, so the site is indiscernible from a natural tooth. PMID:26124837

  5. Soft Rot of Eggplant (Solanum melongena) Caused by Choanephora cucurbitarum in Korea

    PubMed Central

    Jee, Hyeong-Jin

    2005-01-01

    In April 2002 and 2003, soft rot on fruit of eggplant (Solanum melongena) caused by Choanephora cucurbitarum was observed in the experimental fields at Gyeongnam Agricultural Research and Extension Services in Korea. The disease began with water-soaking and dark-green lesions, and then the infected tissues were rapidly rotten. Sporangium was subglobose in shape and sized 40~130 µm. Monosporous sporangiola were elliptic, fusiform or ovoid, brown in color, and measured as 12~20 × 6~14 µm. Sporangiospores having three or more appendages were elliptic, fusiform or ovoid in shape, dark brown or brown in color, and sized 14~20 × 7~16 µm. The fungus grew well on potato dextrose agar between 15 and 40℃ and its optimum growth temperature was 30℃. Based on morphological characteristics, the causal fungus of the fruit soft rot of eggplant was identified as C. cucurbitarum. This is the first report on the soft rot of S. melongena caused by C. cucurbitarum in Korea. PMID:24049494

  6. It's Harder to Splash on Soft Solids.

    PubMed

    Howland, Christopher J; Antkowiak, Arnaud; Castrejón-Pita, J Rafael; Howison, Sam D; Oliver, James M; Style, Robert W; Castrejón-Pita, Alfonso A

    2016-10-28

    Droplets splash when they impact dry, flat substrates above a critical velocity that depends on parameters such as droplet size, viscosity, and air pressure. By imaging ethanol drops impacting silicone gels of different stiffnesses, we show that substrate stiffness also affects the splashing threshold. Splashing is reduced or even eliminated: droplets on the softest substrates need over 70% more kinetic energy to splash than they do on rigid substrates. We show that this is due to energy losses caused by deformations of soft substrates during the first few microseconds of impact. We find that solids with Young's moduli ≲100  kPa reduce splashing, in agreement with simple scaling arguments. Thus, materials like soft gels and elastomers can be used as simple coatings for effective splash prevention. Soft substrates also serve as a useful system for testing splash-formation theories and sheet-ejection mechanisms, as they allow the characteristics of ejection sheets to be controlled independently of the bulk impact dynamics of droplets.

  7. Cigarette ignition of soft furnishings: A literature review with commentary

    NASA Astrophysics Data System (ADS)

    Krasny, John F.

    1987-04-01

    Literature pertinent to the ignition by smoldering cigarettes of upholstered furniture and mattresses (soft furnishings) was searched through early 1986. This included literature on the smoldering behavior of cigarettes in air; their behavior on a variety of substrates simulating soft furnishings; mechanism of smoldering in substrates; relative cigarette ignition resistance of substrates; and relative propensity of commercial cigarette packings to ignite substrates. According to the reviewed literature, the smoldering behavior of cigarettes on substrates differs from that of cigarettes burning in air: on substrates, cigarette temperatures tend to be lower, and burning rates slower. These differences seem to be larger for substrates which ignite than for those which self-extinguish after the cigarette burns out. The characteristics of soft furnishings which insure resistance to cigarette ignition have been established, but those of cigarettes with low propensity to ignite furnishings have not. No mathematical model has been reported for the interaction of cigarette and substrate, but some empirical data do exist.

  8. It's Harder to Splash on Soft Solids

    NASA Astrophysics Data System (ADS)

    Howland, Christopher J.; Antkowiak, Arnaud; Castrejón-Pita, J. Rafael; Howison, Sam D.; Oliver, James M.; Style, Robert W.; Castrejón-Pita, Alfonso A.

    2016-10-01

    Droplets splash when they impact dry, flat substrates above a critical velocity that depends on parameters such as droplet size, viscosity, and air pressure. By imaging ethanol drops impacting silicone gels of different stiffnesses, we show that substrate stiffness also affects the splashing threshold. Splashing is reduced or even eliminated: droplets on the softest substrates need over 70% more kinetic energy to splash than they do on rigid substrates. We show that this is due to energy losses caused by deformations of soft substrates during the first few microseconds of impact. We find that solids with Young's moduli ≲100 kPa reduce splashing, in agreement with simple scaling arguments. Thus, materials like soft gels and elastomers can be used as simple coatings for effective splash prevention. Soft substrates also serve as a useful system for testing splash-formation theories and sheet-ejection mechanisms, as they allow the characteristics of ejection sheets to be controlled independently of the bulk impact dynamics of droplets.

  9. Enhanced performance of microfluidic soft pressure sensors with embedded solid microspheres

    NASA Astrophysics Data System (ADS)

    Shin, Hee-Sup; Ryu, Jaiyoung; Majidi, Carmel; Park, Yong-Lae

    2016-02-01

    The cross-sectional geometry of an embedded microchannel influences the electromechanical response of a soft microfluidic sensor to applied surface pressure. When a pressure is exerted on the surface of the sensor deforming the soft structure, the cross-sectional area of the embedded channel filled with a conductive fluid decreases, increasing the channel’s electrical resistance. This electromechanical coupling can be tuned by adding solid microspheres into the channel. In order to determine the influence of microspheres, we use both analytic and computational methods to predict the pressure responses of soft microfluidic sensors with two different channel cross-sections: a square and an equilateral triangular. The analytical models were derived from contact mechanics in which microspheres were regarded as spherical indenters, and finite element analysis (FEA) was used for simulation. For experimental validation, sensor samples with the two different channel cross-sections were prepared and tested. For comparison, the sensor samples were tested both with and without microspheres. All three results from the analytical models, the FEA simulations, and the experiments showed reasonable agreement confirming that the multi-material soft structure significantly improved its pressure response in terms of both linearity and sensitivity. The embedded solid particles enhanced the performance of soft sensors while maintaining their flexible and stretchable mechanical characteristic. We also provide analytical and experimental analyses of hysteresis of microfluidic soft sensors considering a resistive force to the shape recovery of the polymer structure by the embedded viscous fluid.

  10. Components of soft tissue deformations in subjects with untreated angle's Class III malocclusions: thin-plate spline analysis.

    PubMed

    Singh, G D; McNamara, J A; Lozanoff, S

    1998-01-01

    While the dynamics of maxillo-mandibular allometry associated with treatment modalities available for the management of Class III malocclusions currently are under investigation, developmental aberration of the soft tissues in untreated Class III malocclusions requires specification. In this study, lateral cephalographs of 124 prepubertal European-American children (71 with untreated Class III malocclusion; 53 with Class I occlusion) were traced, and 12 soft-tissue landmarks digitized. Resultant geometries were scaled to an equivalent size and mean Class III and Class I configurations compared. Procrustes analysis established statistical difference (P < 0.001) between the mean configurations. Comparing the overall untreated Class III and Class I configurations, thin-plate spline (TPS) analysis indicated that both affine and non-affine transformations contribute towards the deformation (total spline) of the averaged Class III soft tissue configuration. For non-affine transformations, partial warp 8 had the highest magnitude, indicating large-scale deformations visualized as a combination of columellar retrusion and lower labial protrusion. In addition, partial warp 5 also had a high magnitude, demonstrating upper labial vertical compression with antero-inferior elongation of the lower labio-mental soft tissue complex. Thus, children with Class III malocclusions demonstrate antero-posterior and vertical deformations of the maxillary soft tissue complex in combination with antero-inferior mandibular soft tissue elongation. This pattern of deformations may represent gene-environment interactions, resulting in Class III malocclusions with characteristic phenotypes, that are amenable to orthodontic and dentofacial orthopedic manipulations.

  11. Estimation of soft sediment thickness in Kuala Lumpur based on microtremor observation data

    NASA Astrophysics Data System (ADS)

    Chiew, Chang Chyau; Cheah, Yi Ben; Tan, Chin Guan; Lau, Tze Liang

    2017-10-01

    Seismic site effect is one of the major concerns in earthquake engineering. Soft ground tends to amplify the seismic wave in surficial geological layers. The determination of soft ground thickness on the surface layers of the earth is an important input for seismic hazard assessment. This paper presents an easy and convenient approach to estimate the soft sediment thickness at the site using microtremor observation technique. A total number of 133 survey points were conducted in selected sites around Kuala Lumpur area using a microtremor measuring instrument, but only 103 survey points contributed to the seismic microzonation and sediment thickness plots. The bedrock of Kuala Lumpur area is formed by Kenny Hill Formation, limestone, granite, and the Hawthornden Schist; however, the thickness of surface soft ground formed by alluvial deposits, mine tailings, and residual soils remains unknown. Hence, the predominant frequency of the ground in each site was determined based on Nakamura method. A total number of 14 sites with known depth to bedrock from the supply of geotechnical reports in the study area were determined. An empirical correlation was developed to relate the ground predominant frequency and soft ground thickness. This correlation may contribute to local soil underlying the subsurface of Kuala Lumpur area. The finding provides an important relationship for engineers to estimate the soft ground thickness in Kuala Lumpur area based on the dynamic characteristics of the ground measured from microtremor observation.

  12. Electrostatic interactions between diffuse soft multi-layered (bio)particles: beyond Debye-Hückel approximation and Deryagin formulation.

    PubMed

    Duval, Jérôme F L; Merlin, Jenny; Narayana, Puranam A L

    2011-01-21

    We report a steady-state theory for the evaluation of electrostatic interactions between identical or dissimilar spherical soft multi-layered (bio)particles, e.g. microgels or microorganisms. These generally consist of a rigid core surrounded by concentric ion-permeable layers that may differ in thickness, soft material density, chemical composition and degree of dissociation for the ionogenic groups. The formalism allows the account of diffuse interphases where distributions of ionogenic groups from one layer to the other are position-dependent. The model is valid for any number of ion-permeable layers around the core of the interacting soft particles and covers all limiting situations in terms of nature of interacting particles, i.e. homo- and hetero-interactions between hard, soft or entirely porous colloids. The theory is based on a rigorous numerical solution of the non-linearized Poisson-Boltzmann equation including radial and angular distortions of the electric field distribution within and outside the interacting soft particles in approach. The Gibbs energy of electrostatic interaction is obtained from a general expression derived following the method by Verwey and Overbeek based on appropriate electric double layer charging mechanisms. Original analytical solutions are provided here for cases where interaction takes place between soft multi-layered particles whose size and charge density are in line with Deryagin treatment and Debye-Hückel approximation. These situations include interactions between hard and soft particles, hard plate and soft particle or soft plate and soft particle. The flexibility of the formalism is highlighted by the discussion of few situations which clearly illustrate that electrostatic interaction between multi-layered particles may be partly or predominantly governed by potential distribution within the most internal layers. A major consequence is that both amplitude and sign of Gibbs electrostatic interaction energy may dramatically change depending on the interplay between characteristic Debye length, thickness of ion-permeable layers and their respective protolytic features (e.g. location, magnitude and sign of charge density). This formalism extends a recent model by Ohshima which is strictly limited to interaction between soft mono-shell particles within Deryagin and Debye-Hückel approximations under conditions where ionizable sites are completely dissociated.

  13. Optimal Control of Objects on the Micro- and Nano-Scale by Electrokinetic and Electromagnetic Manipulation: for Bio-Sample Preparation, Quantum Information Devices and Magnetic Drug Delivery

    DTIC Science & Technology

    2010-01-01

    property variations. The system described here is a simple 4-electrode microfluidic device made of polydimethylsiloxane PDMS [50-53] which is reversibly...through the fluid and heat it.) A more detailed description and analysis of the physics of electroosmotic actuation can be found in [46, 83] In...a control algorithm on a standard personal computer. The micro-fluidic device is made out of a soft polymer ( polydimethylsiloxane (PDMS)) and is

  14. Shape diagram of vesicles in Poiseuille flow.

    PubMed

    Coupier, Gwennou; Farutin, Alexander; Minetti, Christophe; Podgorski, Thomas; Misbah, Chaouqi

    2012-04-27

    Soft bodies flowing in a channel often exhibit parachutelike shapes usually attributed to an increase of hydrodynamic constraint (viscous stress and/or confinement). We show that the presence of a fluid membrane leads to the reverse phenomenon and build a phase diagram of shapes-which are classified as bullet, croissant, and parachute-in channels of varying aspect ratio. Unexpectedly, shapes are relatively wider in the narrowest direction of the channel. We highlight the role of flow patterns on the membrane in this response to the asymmetry of stress distribution.

  15. A Rewritable, Reprogrammable, Dual Light-Responsive Polymer Actuator.

    PubMed

    Gelebart, Anne Helene; Mulder, Dirk J; Vantomme, Ghislaine; Schenning, Albertus P H J; Broer, Dirk J

    2017-10-16

    We report on the fabrication of a rewritable and reprogrammable dual-photoresponsive liquid crystalline-based actuator containing an azomerocyanine dye that can be locally converted into the hydroxyazopyridinium form by acid treatment. Each dye absorbs at a different wavelength giving access to programmable actuators, the folding of which can be controlled by using different colors of light. The acidic patterning is reversible and allows the erasing and rewriting of patterns in the polymer film, giving access to reusable, adjustable soft actuators. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  16. Photothermal Nanocomposite Hydrogel Actuator with Electric-Field-Induced Gradient and Oriented Structure.

    PubMed

    Yang, Yang; Tan, Yun; Wang, Xionglei; An, Wenli; Xu, Shimei; Liao, Wang; Wang, Yuzhong

    2018-03-07

    Recent research of hydrogel actuators is still not sophisticated enough to meet the requirement of fast, reversible, complex, and robust reconfiguration. Here, we present a new kind of poly( N-isopropylacrylamide)/graphene oxide gradient hydrogel by utilizing direct current electric field to induce gradient and oriented distribution of graphene oxide into poly( N-isopropylacrylamide) hydrogel. Upon near-infrared light irradiation, the hydrogel exhibited excellent comprehensive actuation performance as a result of directional bending deformation, promising great potential in the application of soft actuators and optomechanical system.

  17. Analysis of soft x-ray/VUV transmission characteristics of Si and Al filters

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

    Joseph, Aby; Modi, Mohammed H.; Singh, Amol

    Ultrathin filters of Al (1500A) and Si (1200A) should exhibit more than 65% transmission above their Labsorption edges in the soft x-ray/vacuum ultra violet region(Si L-edge: 124 A and Al L-edge: 170 A). However, the measured transmission characteristics of these filters showed {approx}40% transmission. The transmission measurements of these filters were carried at the reflectivity beamline of Indus-1 synchrotron source out over a large wavelength range of 120-360A. In order to understand the measured transmission performance a detailed model fitting is performed using the Paratt formalism. It is found that the oxidation of the surface region of the filters ismore » responsible for the reduced transmission performance. Effects of higher harmonics of the toroidal grating monochromator are also considered in the data analysis.« less

  18. Li-ion Battery Separators, Mechanical Integrity and Failure Mechanisms Leading to Soft and Hard Internal Shorts

    PubMed Central

    Zhang, Xiaowei; Sahraei, Elham; Wang, Kai

    2016-01-01

    Separator integrity is an important factor in preventing internal short circuit in lithium-ion batteries. Local penetration tests (nail or conical punch) often produce presumably sporadic results, where in exactly similar cell and test set-ups one cell goes to thermal runaway while the other shows minimal reactions. We conducted an experimental study of the separators under mechanical loading, and discovered two distinct deformation and failure mechanisms, which could explain the difference in short circuit characteristics of otherwise similar tests. Additionally, by investigation of failure modes, we provided a hypothesis about the process of formation of local “soft short circuits” in cells with undetectable failure. Finally, we proposed a criterion for predicting onset of soft short from experimental data. PMID:27581185

  19. Soft Ultraviolet (UV) Photopatterning and Metallization of Self-Assembled Monolayers (SAMs) Formed from the Lipoic Acid Ester of α-Hydroxy-1-acetylpyrene: The Generality of Acid-Catalyzed Removal of Thiol-on-Gold SAMs using Soft UV Light.

    PubMed

    Pukenas, Laurynas; Prompinit, Panida; Nishitha, Boda; Tate, Daniel J; Singh, N D Pradeep; Wälti, Christoph; Evans, Stephen D; Bushby, Richard J

    2017-05-31

    Under a layer of 0.1 M HCl in isopropanol, soft ultraviolet (UV) (365 nm) photolysis of the thiol-on-gold self-assembled monolayer (SAM) derived from the lipoic acid ester of α-hydroxy-1-acetylpyrene results in the expected removal of the acetylpyrene protecting group. When photolyzing through a mask, this can be used to produce a patterned surface and, at a controlled electrochemical potential, it is then possible to selectively and reversibly electrodeposit copper on the photolyzed regions. Rather surprisingly, under these photolysis conditions, there is not only the expected photodeprotection of the ester but also partial removal of the lipoic acid layer which has been formed. In further studies, it is shown that this type of acid-catalyzed photoremoval of SAM layers by soft UV is a rather general phenomenon and results in the partial removal of the thiol-on-gold SAM layers derived from other ω-thiolated carboxylic acids. However, this phenomenon is chain-length dependent. Under conditions in which there is a ∼60% reduction in the thickness of the SAM derived from dithiobutyric acid, the SAM derived from mercaptoundecanoic acid is almost unaffected. The process by which the shorter-chain SAM layers are partially removed is not fully understood because these compounds do not absorb significantly in the 365 nm region of the spectrum! Significantly, this study shows that acid catalysis photolysis of thiol-on-gold SAMs needs to be used with caution.

  20. Imaging review of lipomatous musculoskeletal lesions

    PubMed Central

    Burt, Ashley M.; Huang, Brady K.

    2017-01-01

    Lipomatous lesions are common musculoskeletal lesions that can arise within the soft tissues, bone, neurovascular structures, and synovium. The majority of these lesions are benign, and many of the benign lesions can be diagnosed by radiologic evaluation. However, radiologic differences between benign and malignant lipomatous lesions may be subtle and pathologic correlation is often needed. The use of sonography, computed tomography (CT), and magnetic resonance imaging (MRI) is useful not only in portraying fat within the lesion, but also for evaluating the presence and extent of soft tissue components. Lipomas make up most soft tissue lipomatous lesions, but careful evaluation must be performed to distinguish these lesions from a low-grade liposarcoma. In addition to the imaging appearance, the location of the lesion and the patient demographics can be utilized to help diagnose other soft tissue lipomatous lesions, such as elastofibroma dorsi, angiolipoma, lipoblastoma, and hibernoma. Osseous lipomatous lesions such as a parosteal lipoma and intraosseous lipoma occur less commonly as their soft tissue counterpart, but are also benign. Neurovascular and synovial lipomatous lesions are much rarer lesions but demonstrate more classic radiologic findings, particularly on MRI. A review of the clinical, radiologic, and pathologic characteristics of these lesions is presented. PMID:28474576

  1. Fat-containing soft-tissue masses in children.

    PubMed

    Sheybani, Elizabeth F; Eutsler, Eric P; Navarro, Oscar M

    2016-12-01

    The diagnosis of soft-tissue masses in children can be difficult because of the frequently nonspecific clinical and imaging characteristics of these lesions. However key findings on imaging can aid in diagnosis. The identification of macroscopic fat within a soft-tissue mass narrows the differential diagnosis considerably and suggests a high likelihood of a benign etiology in children. Fat can be difficult to detect with sonography because of the variable appearance of fat using this modality. Fat is easier to recognize using MRI, particularly with the aid of fat-suppression techniques. Although a large portion of fat-containing masses in children are adipocytic tumors, a variety of other tumors and mass-like conditions that contain fat should be considered by the radiologist confronted with a fat-containing mass in a child. In this article we review the sonographic and MRI findings in the most relevant fat-containing soft-tissue masses in the pediatric age group, including adipocytic tumors (lipoma, angiolipoma, lipomatosis, lipoblastoma, lipomatosis of nerve, and liposarcoma); fibroblastic/myofibroblastic tumors (fibrous hamartoma of infancy and lipofibromatosis); vascular anomalies (involuting hemangioma, intramuscular capillary hemangioma, phosphate and tensin homologue (PTEN) hamartoma of soft tissue, fibro-adipose vascular anomaly), and other miscellaneous entities, such as fat necrosis and epigastric hernia.

  2. Testing the Impulsiveness of Solar Flare Heating through Analysis of Dynamic Atmospheric Response

    NASA Astrophysics Data System (ADS)

    Newton, E. K.; Emslie, A. G.; Mariska, J. T.

    1996-03-01

    One crucial test of a solar flare energy transport model is its ability to reproduce the characteristics of the atmospheric motions inferred from soft X-ray line spectra. Using a recently developed diagnostic, the velocity differential emission measure (VDEM), we can obtain from observations a physical measure of the amount of soft X-ray mitting plasma flowing at each velocity, v, and hence the total momentum of the upflowing plasma, without approximation or parametric fitting. We have correlated solar hard X-ray emission profiles by the Yohkoh Hard X-ray telescope with the mass and momentum histories inferred from soft X-ray line profiles observed by the Yohkoh Bragg crystal spectrometers. For suitably impulsive hard X-ray emission, an analysis of the hydrodynamic equations predicts a proportionality between the hard X-ray intensity and the second time derivative of the soft X-ray mitting plasma's momentum. This relationship is borne out by an analysis of 18 disk-center impulsive flares of varying durations, thereby lending support to the hypothesis that a prompt energy deposition mechanism, such as an energetic electron flux, is indeed responsible for the soft X-ray response observed in the rise phase of sufficiently impulsive solar flares.

  3. Behavior of sandwich panels subjected to bending fatigue, axial compression loading and in-plane bending

    NASA Astrophysics Data System (ADS)

    Mathieson, Haley Aaron

    This thesis investigates experimentally and analytically the structural performance of sandwich panels composed of glass fibre reinforced polymer (GFRP) skins and a soft polyurethane foam core, with or without thin GFRP ribs connecting skins. The study includes three main components: (a) out-of-plane bending fatigue, (b) axial compression loading, and (c) in-plane bending of sandwich beams. Fatigue studies included 28 specimens and looked into establishing service life (S-N) curves of sandwich panels without ribs, governed by soft core shear failure and also ribbed panels governed by failure at the rib-skin junction. Additionally, the study compared fatigue life curves of sandwich panels loaded under fully reversed bending conditions (R=-1) with panels cyclically loaded in one direction only (R=0) and established the stiffness degradation characteristics throughout their fatigue life. Mathematical models expressing fatigue life and stiffness degradation curves were calibrated and expanded forms for various loading ratios were developed. Approximate fatigue thresholds of 37% and 23% were determined for non-ribbed panels loaded at R=0 and -1, respectively. Digital imaging techniques showed significant shear contribution significantly (90%) to deflections if no ribs used. Axial loading work included 51 specimens and examined the behavior of panels of various lengths (slenderness ratios), skin thicknesses, and also panels of similar length with various rib configurations. Observed failure modes governing were global buckling, skin wrinkling or skin crushing. In-plane bending involved testing 18 sandwich beams of various shear span-to-depth ratios and skin thicknesses, which failed by skin wrinkling at the compression side. The analytical modeling components of axially loaded panels include; a simple design-oriented analytical failure model and a robust non-linear model capable of predicting the full load-displacement response of axially loaded slender sandwich panels, accounting for P-Delta effects, inherent out-of-straightness profile of any shape at initial conditions, and the excessive shear deformation of soft core and its effect on buckling capacity. Another model was developed to predict the load-deflection response and failure modes of in-plane loaded sandwich beams. After successful verification of the models using experimental results, comprehensive parametric studies were carried out using these models to cover parameters beyond the limitations of the experimental program.

  4. Three-dimensional localization of nanoscale battery reactions using soft X-ray tomography

    DOE PAGES

    Yu, Young-Sang; Farmand, Maryam; Kim, Chunjoong; ...

    2018-03-02

    Battery function is determined by the efficiency and reversibility of the electrochemical phase transformations at solid electrodes. The microscopic tools available to study the chemical states of matter with the required spatial resolution and chemical specificity are intrinsically limited when studying complex architectures by their reliance on two-dimensional projections of thick material. Here in this paper, we report the development of soft X-ray ptychographic tomography, which resolves chemical states in three dimensions at 11 nm spatial resolution. We study an ensemble of nano-plates of lithium iron phosphate extracted from a battery electrode at 50% state of charge. Using a setmore » of nanoscale tomograms, we quantify the electrochemical state and resolve phase boundaries throughout the volume of individual nanoparticles. These observations reveal multiple reaction points, intra-particle heterogeneity, and size effects that highlight the importance of multi-dimensional analytical tools in providing novel insight to the design of the next generation of high-performance devices.« less

  5. Bio-inspired metal-coordinate hydrogels with programmable viscoelastic material functions controlled by longwave UV light.

    PubMed

    Grindy, Scott C; Holten-Andersen, Niels

    2017-06-07

    Control over the viscoelastic mechanical properties of hydrogels intended for use as biomedical materials has long been a goal of soft matter scientists. Recent research has shown that materials made from polymers with reversibly associating transient crosslinks are a promising strategy for controlling viscoelasticity in hydrogels, for example leading to systems with precisely tunable mechanical energy-dissipation. We and others have shown that bio-inspired histidine:transition metal ion complexes allow highly precise and tunable control over the viscoelastic properties of transient network hydrogels. In this paper, we extend the design of these hydrogels such that their viscoelastic properties respond to longwave UV radiation. We show that careful selection of the histidine:transition metal ion crosslink mixtures allows unique control over pre- and post-UV viscoelastic properties. We anticipate that our strategy for controlling stimuli-responsive viscoelastic properties will aid biomedical materials scientists in the development of soft materials with specific stress-relaxing or energy-dissipating properties.

  6. Three-dimensional localization of nanoscale battery reactions using soft X-ray tomography

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

    Yu, Young-Sang; Farmand, Maryam; Kim, Chunjoong

    Battery function is determined by the efficiency and reversibility of the electrochemical phase transformations at solid electrodes. The microscopic tools available to study the chemical states of matter with the required spatial resolution and chemical specificity are intrinsically limited when studying complex architectures by their reliance on two-dimensional projections of thick material. Here in this paper, we report the development of soft X-ray ptychographic tomography, which resolves chemical states in three dimensions at 11 nm spatial resolution. We study an ensemble of nano-plates of lithium iron phosphate extracted from a battery electrode at 50% state of charge. Using a setmore » of nanoscale tomograms, we quantify the electrochemical state and resolve phase boundaries throughout the volume of individual nanoparticles. These observations reveal multiple reaction points, intra-particle heterogeneity, and size effects that highlight the importance of multi-dimensional analytical tools in providing novel insight to the design of the next generation of high-performance devices.« less

  7. Optimizing the field distribution of a Halbach type permanent magnet cylinder using the soft iron and superhard magnet

    NASA Astrophysics Data System (ADS)

    Xu, Xiaonong; Lu, Dingwei; Xu, Xibin; Yu, Yang; Gu, Min

    2018-01-01

    When a conventional Halbach type Hollow Cylindrical Permanent Magnet Array (HCPMA) is used to generate magnetic induction over the magnitude of coercivity μ0Hc, some detrimental parasitic magnetic phenomena, such as the demagnetization, magnetization reversal, and vortexes of magnetization, can appear in the interior of the magnets. We present a self-consistent quantitative analysis of the magnetization and magnetic induction distributions inside the magnetic array by considering the anisotropic and nonlinear magnetization functions of the materials consisting of the array. These numeric simulations reveal novel magnetization structures resulted from the self-field of array. We demonstrate that both the field uniformity and magnetic flux in the pole gap can be modulated by partially substituting the magnets of high energy products with the soft irons and the superhard magnets. We also show how the optimized substitution parameters can be obtained for a HCPMA achieving the best field uniformity or the maximum magnetic flux.

  8. Three-dimensional structure and multistable optical switching of triple-twisted particle-like excitations in anisotropic fluids.

    PubMed

    Smalyukh, Ivan I; Lansac, Yves; Clark, Noel A; Trivedi, Rahul P

    2010-02-01

    Control of structures in soft materials with long-range order forms the basis for applications such as displays, liquid-crystal biosensors, tunable lenses, distributed feedback lasers, muscle-like actuators and beam-steering devices. Bistable, tristable and multistable switching of well-defined structures of molecular alignment is of special interest for all of these applications. Here we describe the facile optical creation and multistable switching of localized configurations in the molecular orientation field of a chiral nematic anisotropic fluid. These localized chiro-elastic particle-like excitations--dubbed 'triple-twist torons'--are generated by vortex laser beams and embed the localized three-dimensional (3D) twist into a uniform background. Confocal polarizing microscopy and computer simulations reveal their equilibrium internal structures, manifesting both skyrmion-like and Hopf fibration features. Robust generation of torons at predetermined locations combined with both optical and electrical reversible switching can lead to new ways of multistable structuring of complex photonic architectures in soft materials.

  9. Wave energy transfer in elastic half-spaces with soft interlayers.

    PubMed

    Glushkov, Evgeny; Glushkova, Natalia; Fomenko, Sergey

    2015-04-01

    The paper deals with guided waves generated by a surface load in a coated elastic half-space. The analysis is based on the explicit integral and asymptotic expressions derived in terms of Green's matrix and given loads for both laminate and functionally graded substrates. To perform the energy analysis, explicit expressions for the time-averaged amount of energy transferred in the time-harmonic wave field by every excited guided or body wave through horizontal planes and lateral cylindrical surfaces have been also derived. The study is focused on the peculiarities of wave energy transmission in substrates with soft interlayers that serve as internal channels for the excited guided waves. The notable features of the source energy partitioning in such media are the domination of a single emerging mode in each consecutive frequency subrange and the appearance of reverse energy fluxes at certain frequencies. These effects as well as modal and spatial distribution of the wave energy coming from the source into the substructure are numerically analyzed and discussed.

  10. Reverse-time migration for subsurface imaging using single- and multi- frequency components

    NASA Astrophysics Data System (ADS)

    Ha, J.; Kim, Y.; Kim, S.; Chung, W.; Shin, S.; Lee, D.

    2017-12-01

    Reverse-time migration is a seismic data processing method for obtaining accurate subsurface structure images from seismic data. This method has been applied to obtain more precise complex geological structure information, including steep dips, by considering wave propagation characteristics based on two-way traveltime. Recently, various studies have reported the characteristics of acquired datasets from different types of media. In particular, because real subsurface media is comprised of various types of structures, seismic data represent various responses. Among them, frequency characteristics can be used as an important indicator for analyzing wave propagation in subsurface structures. All frequency components are utilized in conventional reverse-time migration, but analyzing each component is required because they contain inherent seismic response characteristics. In this study, we propose a reverse-time migration method that utilizes single- and multi- frequency components for analyzing subsurface imaging. We performed a spectral decomposition to utilize the characteristics of non-stationary seismic data. We propose two types of imaging conditions, in which decomposed signals are applied in complex and envelope traces. The SEG/EAGE Overthrust model was used to demonstrate the proposed method, and the 1st derivative Gaussian function with a 10 Hz cutoff was used as the source signature. The results were more accurate and stable when relatively lower frequency components in the effective frequency range were used. By combining the gradient obtained from various frequency components, we confirmed that the results are clearer than the conventional method using all frequency components. Also, further study is required to effectively combine the multi-frequency components.

  11. Investigation of Finite Sources through Time Reversal

    NASA Astrophysics Data System (ADS)

    Kremers, S.; Brietzke, G.; Igel, H.; Larmat, C.; Fichtner, A.; Johnson, P. A.; Huang, L.

    2008-12-01

    Under certain conditions time reversal is a promising method to determine earthquake source characteristics without any a-priori information (except the earth model and the data). It consists of injecting flipped-in-time records from seismic stations within the model to create an approximate reverse movie of wave propagation from which the location of the source point and other information might be inferred. In this study, the backward propagation is performed numerically using a spectral element code. We investigate the potential of time reversal to recover finite source characteristics (e.g., size of ruptured area, location of asperities, rupture velocity etc.). We use synthetic data from the SPICE kinematic source inversion blind test initiated to investigate the performance of current kinematic source inversion approaches (http://www.spice- rtn.org/library/valid). The synthetic data set attempts to reproduce the 2000 Tottori earthquake with 33 records close to the fault. We discuss the influence of relaxing the ignorance to prior source information (e.g., origin time, hypocenter, fault location, etc.) on the results of the time reversal process.

  12. The role of soft computing in intelligent machines.

    PubMed

    de Silva, Clarence W

    2003-08-15

    An intelligent machine relies on computational intelligence in generating its intelligent behaviour. This requires a knowledge system in which representation and processing of knowledge are central functions. Approximation is a 'soft' concept, and the capability to approximate for the purposes of comparison, pattern recognition, reasoning, and decision making is a manifestation of intelligence. This paper examines the use of soft computing in intelligent machines. Soft computing is an important branch of computational intelligence, where fuzzy logic, probability theory, neural networks, and genetic algorithms are synergistically used to mimic the reasoning and decision making of a human. This paper explores several important characteristics and capabilities of machines that exhibit intelligent behaviour. Approaches that are useful in the development of an intelligent machine are introduced. The paper presents a general structure for an intelligent machine, giving particular emphasis to its primary components, such as sensors, actuators, controllers, and the communication backbone, and their interaction. The role of soft computing within the overall system is discussed. Common techniques and approaches that will be useful in the development of an intelligent machine are introduced, and the main steps in the development of an intelligent machine for practical use are given. An industrial machine, which employs the concepts of soft computing in its operation, is presented, and one aspect of intelligent tuning, which is incorporated into the machine, is illustrated.

  13. Ultra-Soft PDMS-Based Magnetoactive Elastomers as Dynamic Cell Culture Substrata

    PubMed Central

    Mayer, Matthias; Rabindranath, Raman; Börner, Juliane; Hörner, Eva; Bentz, Alexander; Salgado, Josefina; Han, Hong; Böse, Holger; Probst, Jörn; Shamonin, Mikhail; Monkman, Gareth J.; Schlunck, Günther

    2013-01-01

    Mechanical cues such as extracellular matrix stiffness and movement have a major impact on cell differentiation and function. To replicate these biological features in vitro, soft substrata with tunable elasticity and the possibility for controlled surface translocation are desirable. Here we report on the use of ultra-soft (Young’s modulus <100 kPa) PDMS-based magnetoactive elastomers (MAE) as suitable cell culture substrata. Soft non-viscous PDMS (<18 kPa) is produced using a modified extended crosslinker. MAEs are generated by embedding magnetic microparticles into a soft PDMS matrix. Both substrata yield an elasticity-dependent (14 vs. 100 kPa) modulation of α-smooth muscle actin expression in primary human fibroblasts. To allow for static or dynamic control of MAE material properties, we devise low magnetic field (≈40 mT) stimulation systems compatible with cell-culture environments. Magnetic field-instigated stiffening (14 to 200 kPa) of soft MAE enhances the spreading of primary human fibroblasts and decreases PAX-7 transcription in human mesenchymal stem cells. Pulsatile MAE movements are generated using oscillating magnetic fields and are well tolerated by adherent human fibroblasts. This MAE system provides spatial and temporal control of substratum material characteristics and permits novel designs when used as dynamic cell culture substrata or cell culture-coated actuator in tissue engineering applications or biomedical devices. PMID:24204603

  14. Relationship between severity of shoulder subluxation and soft-tissue injury in hemiplegic stroke patients.

    PubMed

    Huang, Shih-Wei; Liu, Sen-Yung; Tang, Hao-Wei; Wei, Ta-Sen; Wang, Wei-Te; Yang, Chao-Pin

    2012-09-01

    The aims of this study were: (i) to determine whether the severity of post-hemiplegic shoulder subluxation in stroke patients correlates with soft-tissue injury; and (ii) to determine the shoulder subluxation measurement cut-off points that are indications for further ultrasound examination for soft-tissue injuries in these patients. Cross-sectional study. A total of 39 stroke patients with shoulder subluxation. Shoulder subluxation was evaluated by physical examination, radiography and ultrasound. Soft-tissue injuries were assessed by ultrasound. Subluxation parameters were entered into stepwise logistic regression analyses to predict biceps and supraspinatus tendonitis. With the assumption that shoulder subluxation can be a predisposing factor for tendonitis, receiver operating characteristic curves for shoulder subluxation parameters of the affected side were used to determine cut-off points for optimal sensitivity and specificity of biceps and supraspinatus tendonitis. Shoulder subluxation lateral distance, measured by physical examination, is a predictor for supraspinatus tendonitis (odds ratio = 34.9, p = 0.036). Further ultrasound investigation for soft-tissue injury is indicated when subluxation lateral distance, measured by physical examination is ≥ 2.25 cm or, measured by radiographic examination, ≥ 3.18 cm for lateral distance, ≥ 3.08 cm for vertical distance, or ≥ 2.65 cm for horizontal distance. When post-hemiplegic shoulder subluxation measurements exceed the above-mentioned cut-off points in physical or radiographic examinations, further ultrasound evaluation for soft-tissue injury is recommended.

  15. Propagation characteristics of a focused laser beam in a strontium barium niobate photorefractive crystal under reverse external electric field.

    PubMed

    Guo, Q L; Liang, B L; Wang, Y; Deng, G Y; Jiang, Y H; Zhang, S H; Fu, G S; Simmonds, P J

    2014-10-01

    The propagation characteristics of a focused laser beam in a SBN:75 photorefractive crystal strongly depend on the signal-to-background intensity ratio (R=Is/Ib) under reverse external electric field. In the range 20>R>0.05, the laser beam shows enhanced self-defocusing behavior with increasing external electric field, while it shows self-focusing in the range 0.03>R>0.01. Spatial solitons are observed under a suitable reverse external electric field for R=0.025. A theoretical model is proposed to explain the experimental observations, which suggest a new type of soliton formation due to "enhancement" not "screening" of the external electrical field.

  16. Hamilton Standard Q-fan demonstrator dynamic pitch change test program, volume 1

    NASA Technical Reports Server (NTRS)

    Demers, W. J.; Nelson, D. J.; Wainauski, H. S.

    1975-01-01

    Tests of a full scale variable pitch fan engine to obtain data on the structural characteristics, response times, and fan/core engine compatibility during transient changes in blade angle, fan rpm, and engine power is reported. Steady state reverse thrust tests with a take off nozzle configuration were also conducted. The 1.4 meter diameter, 13 bladed controllable pitch fan was driven by a T55 L 11A engine with power and blade angle coordinated by a digital computer. The tests demonstrated an ability to change from full forward thrust to reverse thrust in less than one (1) second. Reverse thrust was effected through feather and through flat pitch; structural characteristics and engine/fan compatibility were within satisfactory limits.

  17. Smart nickel oxide materials for the applications of energy efficiency and storage

    NASA Astrophysics Data System (ADS)

    Lin, Feng

    The present dissertation studies nickel oxide-based materials for the application of electrochromic windows and lithium-air batteries. The materials were fabricated via radio frequency magnetron sputtering and subsequently post-treated with thermal evaporation and ozone exposure. The strategies to improve electrochromic performance of nickel oxide materials were investigated including compositional control, morphology tuning, modification of electronic structure and interface engineering (i.e., Li2O 2, graphene). The electrochemical properties of the resulting materials were characterized in lithium ion electrolytes. Extremely high performing nickel oxide-based electrochromic materials were obtained in terms of optical modulation, switching kinetics, bleached-state transparency and durability, which promise the implementation of these materials for practical smart windows. With the aid of advanced synchrotron X-ray absorption spectroscopy, it is reported for the first time that the electrochromic effect in multicomponent nickel oxide-based materials arises from the reversible formation of hole states in the NiO6 cluster accompanying with the reversible formation of Li2O2. The reversible formation of Li2O 2 was successfully leveraged with the study of electro-catalysts and cathode materials for lithium-air batteries. The reversibility of Li 2O2 was thoroughly investigated using soft X-ray absorption spectroscopy and theoretical simulation, which substantiates the promise of using electrochromic films as electro-catalysts and/or cathode materials in lithium-air batteries.

  18. The Orange Side of Disperse Red 1: Humidity-Driven Color Switching in Supramolecular Azo-Polymer Materials Based on Reversible Dye Aggregation.

    PubMed

    Schoelch, Simon; Vapaavuori, Jaana; Rollet, Frédéric-Guillaume; Barrett, Christopher J

    2017-01-01

    Humidity detection, and the quest for low-cost facile humidity-sensitive indicator materials is of great interest for many fields, including semi-conductor processing, food transport and storage, and pharmaceuticals. Ideal humidity-detection materials for a these applications might be based on simple clear optical readout with no power supply, i.e.: a clear color change observed by the naked eye of any untrained observer, since it doesn't require any extra instrumentation or interpretation. Here, the introduction of a synthesis-free one-step procedure, based on physical mixing of easily available commercial materials, for producing a humidity memory material which can be easily painted onto a wide variety of surfaces and undergoes a remarkable color change (approximately 100 nm blue-shift of λ MAX ) upon exposure to various thresholds of levels of ambient humidity is reported. This strong color change, easily visible to as a red-to-orange color switch, is locked in until inspection, but can then be restored reversibly if desired, after moderate heating. By taking advantage of spontaneously-forming reversible 'soft' supramolecular bonds between a red-colored azo dye and a host polymer matrix, a reversible dye 'migration' aggregation appearing orange, and dis-aggregation back to red can be achieved, to function as the sensor. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Relaxation of bending stresses and the reversibility of residual stresses in amorphous soft magnetic alloys

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

    Kekalo, I. B.; Mogil’nikov, P. S., E-mail: pavel-mog@mail.ru

    2015-06-15

    The reversibility of residual bending stresses is revealed in ribbon samples of cobalt- and iron-based amorphous alloys Co{sub 69}Fe{sub 3.7}Cr{sub 3.8}Si{sub 12.5}B{sub 11} and Fe{sub 57}Co{sub 31}Si{sub 2.9}B{sub 9.1}: the ribbons that are free of applied stresses and bent under the action of residual stresses become completely or incompletely straight upon annealing at the initial temperatures. The influence of annealing on the relaxation of bending stresses is studied. Preliminary annealing is found to sharply decrease the relaxation rate of bending stresses, and the initial stage of fast relaxation of these stresses is absent. Complete straightening of preliminarily annealed ribbons ismore » shown to occur at significantly higher temperatures than that of the initial ribbons. Incomplete straightening of the ribbons is explained by the fact that bending stresses relaxation at high annealing temperatures proceeds due to both reversible anelastic deformation and viscous flow, which is a fully irreversible process. Incomplete reversibility is also caused by irreversible processes, such as the release of excess free volume and clustering (detected by small-angle X-ray scattering). The revealed differences in the relaxation processes that occur in the cobalt- and iron-based amorphous alloys are discussed in terms of different atomic diffusion mobilities in these alloys.« less

  20. Assessing the intrinsic precision of 3D/3D rigid image registration results for patient setup in the absence of a ground truth.

    PubMed

    Wu, Jian; Murphy, Martin J

    2010-06-01

    To assess the precision and robustness of patient setup corrections computed from 3D/3D rigid registration methods using image intensity, when no ground truth validation is possible. Fifteen pairs of male pelvic CTs were rigidly registered using four different in-house registration methods. Registration results were compared for different resolutions and image content by varying the image down-sampling ratio and by thresholding out soft tissue to isolate bony landmarks. Intrinsic registration precision was investigated by comparing the different methods and by reversing the source and the target roles of the two images being registered. The translational reversibility errors for successful registrations ranged from 0.0 to 1.69 mm. Rotations were less than 1 degrees. Mutual information failed in most registrations that used only bony landmarks. The magnitude of the reversibility error was strongly correlated with the success/ failure of each algorithm to find the global minimum. Rigid image registrations have an intrinsic uncertainty and robustness that depends on the imaging modality, the registration algorithm, the image resolution, and the image content. In the absence of an absolute ground truth, the variation in the shifts calculated by several different methods provides a useful estimate of that uncertainty. The difference observed by reversing the source and target images can be used as an indication of robust convergence.

  1. COS Observations of SN1987A

    NASA Astrophysics Data System (ADS)

    McCray, Richard; France, K.; Kirshner, R. P.; SAINTS Collaboration

    2012-01-01

    We present the most sensitive ultraviolet observations of Supernova 1987A to date. Imaging spectroscopy from the Hubble Space Telescope-Cosmic Origins Spectrograph shows many narrow (v - 300 km/s) emission lines from the circumstellar ring, broad (v - 10 - 20 × 103 km/s) emission lines from the reverse shock, and ultraviolet continuum emission. The high signal-to-noise (> 40 per resolution element) broad Ly α emission is excited by soft X-ray and EUV heating of mostly neutral gas in the circumstellar ring and outer supernova debris. The ultraviolet continuum at - > 1350 A can be explained by H I 2-photon (2s 2S1/2 - 1s 2S1/2) emission from the same region. We confirm our earlier, tentative detection of N V -1240 emission from the reverse shock and we present the first detections of broad He II 1640, C IV -1550, and N IV] 1486 emission lines from the reverse shock. The helium abundance in the high velocity material is He/H = 0.14 +/- 0.06. The N V/H line ratio requires partial ion-electron equilibration (Te/Tp - 0.14 - 0.35). We find that the N/C abundance ratio in the gas crossing the reverse shock is significantly higher than that in the circumstellar ring, a result we attribute to continued CNO processing in the supernova progenitor subsequent to the expulsion of the circumstellar ring.

  2. Recoil hysteresis of Sm -Co/Fe exchange-spring bilayers

    NASA Astrophysics Data System (ADS)

    Kang, K.; Lewis, L. H.; Jiang, J. S.; Bader, S. D.

    2005-12-01

    The exchange-spring behavior found in Sm-Co (20nm)/Fe epitaxial bilayer films was investigated by analyzing major hysteresis and recoil curves as a function of anneal conditions. The hard layer consists of nanocrystalline intermetallic Sm-Co hexagonal phases (majority phase Sm2Co7 with SmCo3 and SmCo5). Recoil curves, obtained from the successive removal to remanence and reapplication of an increasingly negative field from the major demagnetization curve, reveal the reversible and irreversible components of the magnetization. The Sm-Co thickness was fixed at 20nm while the Fe thicknesses of 10 and 20nm were studied, with ex situ annealing carried out in evacuated, sealed silica tubes at different temperatures. The peak in the recoil curve area is associated with the coercivity of the hard phase. The development of the soft component magnetization is revealed by the departure of the recoil area from zero with application of a reverse field. These two features together confirm that annealing stabilizes the 10nm Fe bilayer sample against local magnetic reversal while it weakens the 20nm bilayer sample. Furthermore, in both its as-deposited and annealed states the Sm -Co/Fe bilayer of 10nm Fe thickness always displays a higher exchange field and smaller recoil loop areas than the bilayer of 20nm Fe thickness, consistent with a stronger exchange response and more reversible magnetization in the former.

  3. One-Way Multishape-Memory Effect and Tunable Two-Way Shape Memory Effect of Ionomer Poly(ethylene-co-methacrylic acid).

    PubMed

    Lu, Lu; Li, Guoqiang

    2016-06-15

    Reversible elongation by cooling and contraction by heating, without the need for repeated programming, is well-known as the two-way shape-memory effect (2W-SME). This behavior is contrary to the common physics-contraction when cooling and expansion when heating. Materials with such behavior may find many applications in real life, such as self-sufficient grippers, fastening devices, optical gratings, soft actuators, and sealant. Here, it is shown that ionomer Surlyn 8940, a 50-year old polymer, exhibits both one-way multishape-memory effects and tunable two-way reversible actuation. The required external tensile stress to trigger the tunable 2W-SME is very low when randomly jumping the temperatures within the melting transition window. With a proper one-time programming, "true" 2W-SME (i.e., 2W-SME without the need for an external tensile load) is also achieved. A long training process is not needed to trigger the tunable 2W-SME. Instead, a proper one-time tensile programming is sufficient to trigger repeated and tunable 2W-SME. Because the 2W-SME of the ionomer Surlyn is driven by the thermally reversible network, here crystallization and melting transitions of the semicrystalline poly(ethylene-co-methacrylic acid), it is believed that a class of thermally reversible polymers should also exhibit tunable 2W-SMEs.

  4. Popularity of suture materials among residents and faculty members of a postdoctoral periodontology program.

    PubMed

    Maksoud, Mohamed; Koo, Samuel; Barouch, Kasumi; Karimbux, Nadeem

    2014-02-01

    The aim of the present study was to determine the favoritism of suture materials among a group of clinicians at a teaching institution. The surveys included 11 absorbable and nine non-absorbable sutures. The surveyor was asked to select his or her suture preferences when it comes to using it in 13 different, commonly-performed surgical procedures. The surveys showed overall preferences for non-absorbable versus absorbable sutures. Chromic Gut with a 4-0 diameter thread reverse cutting FS2 needle was the most favored suture. For periodontal bone grafts and hard tissue ridge augmentation, polytetrafluoroethylene with a 4-0 thread and FS2 needle was preferred. For autogenous gingival grafts, gingival allografts, connective tissue grafts, frenectomy and frenoplasty, Chromic Gut with 5-0 diameter thread reverse cutting P3 needle was favored. For extraction socket preservation, soft tissue canine exposure, ridge augmentation, and dental implants, Chromic Gut with 4-0 diameter thread reverse cutting FS2 needle was preferred, and for sinus augmentation, Vicryl with a 4-0 diameter thread reverse cutting FS2 needle was favored. Absorbable sutures were preferred in the majority of periodontal procedures; however, non-absorbable sutures were favored in procedures that required longer healing or better stability of the flap edges in cases of periodontal and ridge augmentation. © 2013 Wiley Publishing Asia Pty Ltd.

  5. Quorum Sensing Signaling Molecules Produced by Reference and Emerging Soft-Rot Bacteria (Dickeya and Pectobacterium spp.)

    PubMed Central

    Crépin, Alexandre; Barbey, Corinne; Beury-Cirou, Amélie; Hélias, Valérie; Taupin, Laure; Reverchon, Sylvie; Nasser, William; Faure, Denis; Dufour, Alain; Orange, Nicole; Feuilloley, Marc; Heurlier, Karin; Burini, Jean-François; Latour, Xavier

    2012-01-01

    Background Several small diffusible molecules are involved in bacterial quorum sensing and virulence. The production of autoinducers-1 and -2, quinolone, indole and γ-amino butyrate signaling molecules was investigated in a set of soft-rot bacteria belonging to six Dickeya or Pectobacterium species including recent or emerging potato isolates. Methodology/Principal Findings Using bacterial biosensors, immunoassay, and chromatographic analysis, we showed that soft-rot bacteria have the common ability to produce transiently during their exponential phase of growth the N-3-oxo-hexanoyl- or the N-3-oxo-octanoyl-l-homoserine lactones and a molecule of the autoinducer-2 family. Dickeya spp. produced in addition the indole-3-acetic acid in tryptophan-rich conditions. All these signaling molecules have been identified for the first time in the novel Dickeya solani species. In contrast, quinolone and γ-amino butyrate signals were not identified and the corresponding synthases are not present in the available genomes of soft-rot bacteria. To determine if the variations of signal production according to growth phase could result from expression modifications of the corresponding synthase gene, the respective mRNA levels were estimated by reverse transcriptase-PCR. While the N-acyl-homoserine lactone production is systematically correlated to the synthase expression, that of the autoinducer-2 follows the expression of an enzyme upstream in the activated methyl cycle and providing its precursor, rather than the expression of its own synthase. Conclusions/Significance Despite sharing the S-adenosylmethionine precursor, no strong link was detected between the production kinetics or metabolic pathways of autoinducers-1 and -2. In contrast, the signaling pathway of autoinducer-2 seems to be switched off by the indole-3-acetic acid pathway under tryptophan control. It therefore appears that the two genera of soft-rot bacteria have similarities but also differences in the mechanisms of communication via the diffusible molecules. Our results designate autoinducer-1 lactones as the main targets for a global biocontrol of soft-rot bacteria communications, including those of emerging isolates. PMID:22539957

  6. DISCOVERY OF X-RAY EMISSION FROM SUPERNOVA 1970G WITH CHANDRA: FILLING THE VOID BETWEEN SUPERNOVAE AND SUPERNOVA REMNANTS

    NASA Technical Reports Server (NTRS)

    Immler, Stefan; Kuntz, K. D.

    2005-01-01

    We report the discovery of X-ray emission from SN 1970G in M101, 35 yr after its outburst, using deep X-ray imaging with the Chundra X-Ray Observatory. The Chandra ACIS spectrum shows that the emission is soft (52 keV) and characteristic of the reverse-shock region. The X-ray luminosity, Lo,,, = (1.1 3 0.2) x lo3# ergs s-1, is likely caused by the interaction of the supernova shock with dense circumstellar matter. If the material was deposited by the stellar wind from the progenitor, a mass-loss rate of M = (2.6 ? 0.4) x M, yr-I (v,/lO km s-I) is inferred. Utilizing the high-resolution Chandra ACIS data of SN 1970G and its environment, we reconstruct the X-ray lightcurve from previous ROSAT HRI, PSPC, and XMM-Newton EPIC observations, and find a best-fit linear rate of decline of L cc t-# with index s = 2.7 t 0.9 over a period of -20-35 yr after the outburst. As the oldest supernova detected in X-rays, SN 1970G allows, for the first time, direct observation of the transition from a supenova to its supernova remnant phase.

  7. A remotely interrogatable sensor for chemical monitoring

    NASA Technical Reports Server (NTRS)

    Stoyanov, P. G.; Doherty, S. A.; Grimes, C. A.; Seitz, W. R.

    1998-01-01

    A new type of continuously operating, in-situ, remotely monitored sensor is presented. The sensor is comprised of a thin film array of magnetostatically coupled, magnetically soft ferromagnetic thin film structures, adhered to or encased within a thin polymer layer. The polymer is made so that it swells or shrinks in response to the chemical analyte of interest, which in this case is pH. As the polymer swells or shrinks, the magnetostatic coupling between the magnetic elements changes, resulting in changes in the magnetic switching characteristics of the sensor. Placed within a sinusoidal magnetic field the magnetization vector of the coupled sensor elements periodically reverses directions, generating magnetic flux that can be remotely detected as a series of voltage spikes in appropriately placed pickup coils. one preliminary sensor design consists of four triangles, initially spaced approximately 50 micrometers apart, arranged to form a 12 mm x 12 mm square with the triangle tips centered at a common origin. Our preliminary work has focused on monitoring of pH using a lightly crosslinked pH sensitive polymer layer of hydroxyethylmethacrylate and 2-(dimethylamino) ethylmethacrylate. As the polymer swells or shrinks the magnetostatic coupling between the triangles changes, resulting in measurable changes in the amplitude of the detected voltage spirits.

  8. Establishment and Characterization of a Telomerase-Immortalized Sheep Trophoblast Cell Line.

    PubMed

    Zhang, Yufei; Shi, Jing; Liu, Shuying

    2016-01-01

    The primary sheep trophoblast cells (STCs) have a finite lifespan in culture. This feature limits the scope for long-term in vitro studies with STCs. This study was an attempt to establish and characterize a telomerase-immortalized sheep trophoblast cell line. STCs were isolated and purified by using Percoll and specific immunoaffinity purification, respectively. The purified STCs were transfected with a plasmid carrying sequences of human telomerase reverse transcriptase (hTERT) to create immortalized sheep trophoblast cell line (hTERT-STCs). hTERT-STCs showed a stable expression of hTERT gene, serially passaged for a year, and showed active proliferation without signs of senescence. Cytokeratin 7 (CK-7), secreted human chorionic gonadotrophin subunit β (CG-β), placental lactogen (PL), and endogenous jaagsiekte sheep retrovirus (enJSRV) envelope genes were expressed in hTERT-STCs. Transwell cell invasion assay indicated that hTERT-STCs still possessed the same invasive characteristics as normal primary sheep trophoblast cells. hTERT-STCs could not grow in soft agar and did not develop into tumors in nude mice. In this study, we established a strain of immortalized sheep trophoblast cell line which could be gainfully employed in the future as an experimental model to study trophoblast cells with secretory function, invasive features, and probable biological function of enJSRV envelope genes.

  9. Construction of Polynuclear Lanthanide (Ln = Dy(III), Tb(III), and Nd(III)) Cage Complexes Using Pyridine-Pyrazole-Based Ligands: Versatile Molecular Topologies and SMM Behavior.

    PubMed

    Bala, Sukhen; Sen Bishwas, Mousumi; Pramanik, Bhaskar; Khanra, Sumit; Fromm, Katharina M; Poddar, Pankaj; Mondal, Raju

    2015-09-08

    Employment of two different pyridyl-pyrazolyl-based ligands afforded three octanuclear lanthanide(III) (Ln = Dy, Tb) cage compounds and one hexanuclear neodymium(III) coordination cage, exhibiting versatile molecular architectures including a butterfly core. Relatively less common semirigid pyridyl-pyrazolyl-based asymmetric ligand systems show an interesting trend of forming polynuclear lanthanide cage complexes with different coordination environments around the metal centers. It is noteworthy here that construction of lanthanide complex itself is a challenging task in a ligand system as soft N-donor rich as pyridyl-pyrazol. We report herein some lanthanide complexes using ligand containing only one or two O-donors compare to five N-coordinating sites. The resultant multinuclear lanthanide complexes show interesting magnetic and spectroscopic features originating from different spatial arrangements of the metal ions. Alternating current (ac) susceptibility measurements of the two dysprosium complexes display frequency- and temperature-dependent out-of-phase signals in zero and 0.5 T direct current field, a typical characteristic feature of single-molecule magnet (SMM) behavior, indicating different energy reversal barriers due to different molecular topologies. Another aspect of this work is the occurrence of the not-so-common SMM behavior of the terbium complex, further confirmed by ac susceptibility measurement.

  10. Effect of a core-softened O-O interatomic interaction on the shock compression of fused silica

    NASA Astrophysics Data System (ADS)

    Izvekov, Sergei; Weingarten, N. Scott; Byrd, Edward F. C.

    2018-03-01

    Isotropic soft-core potentials have attracted considerable attention due to their ability to reproduce thermodynamic, dynamic, and structural anomalies observed in tetrahedral network-forming compounds such as water and silica. The aim of the present work is to assess the relevance of effective core-softening pertinent to the oxygen-oxygen interaction in silica to the thermodynamics and phase change mechanisms that occur in shock compressed fused silica. We utilize the MD simulation method with a recently published numerical interatomic potential derived from an ab initio MD simulation of liquid silica via force-matching. The resulting potential indicates an effective shoulder-like core-softening of the oxygen-oxygen repulsion. To better understand the role of the core-softening we analyze two derivative force-matching potentials in which the soft-core is replaced with a repulsive core either in the three-body potential term or in all the potential terms. Our analysis is further augmented by a comparison with several popular empirical models for silica that lack an explicit core-softening. The first outstanding feature of shock compressed glass reproduced with the soft-core models but not with the other models is that the shock compression values at pressures above 20 GPa are larger than those observed under hydrostatic compression (an anomalous shock Hugoniot densification). Our calculations indicate the occurrence of a phase transformation along the shock Hugoniot that we link to the O-O repulsion core-softening. The phase transformation is associated with a Hugoniot temperature reversal similar to that observed experimentally. With the soft-core models, the phase change is an isostructural transformation between amorphous polymorphs with no associated melting event. We further examine the nature of the structural transformation by comparing it to the Hugoniot calculations for stishovite. For stishovite, the Hugoniot exhibits temperature reversal and associated phase transformation, which is a transition to a disordered phase (liquid or dense amorphous), regardless of whether or not the model accounts for core-softening. The onset pressures of the transformation predicted by different models show a wide scatter within 60-110 GPa; for potentials without core-softening, the onset pressure is much higher than 110 GPa. Our results show that the core-softening of the interaction in the oxygen subsystem of silica is the key mechanism for the structural transformation and thermodynamics in shock compressed silica. These results may provide an important contribution to a unified picture of anomalous response to shock compression observed in other network-forming oxides and single-component systems with core-softening of effective interactions.

  11. Toward quantifying the composition of soft tissues by spectral CT with Medipix3.

    PubMed

    Ronaldson, J Paul; Zainon, Rafidah; Scott, Nicola Jean Agnes; Gieseg, Steven Paul; Butler, Anthony P; Butler, Philip H; Anderson, Nigel G

    2012-11-01

    To determine the potential of spectral computed tomography (CT) with Medipix3 for quantifying fat, calcium, and iron in soft tissues within small animal models and surgical specimens of diseases such as fatty liver (metabolic syndrome) and unstable atherosclerosis. The spectroscopic method was applied to tomographic data acquired using a micro-CT system incorporating a Medipix3 detector array with silicon sensor layer and microfocus x-ray tube operating at 50 kVp. A 10 mm diameter perspex phantom containing a fat surrogate (sunflower oil) and aqueous solutions of ferric nitrate, calcium chloride, and iodine was imaged with multiple energy bins. The authors used the spectroscopic characteristics of the CT number to establish a basis for the decomposition of soft tissue components. The potential of the method of constrained least squares for quantifying different sets of materials was evaluated in terms of information entropy and degrees of freedom, with and without the use of a volume conservation constraint. The measurement performance was evaluated quantitatively using atheroma and mouse equivalent phantoms. Finally the decomposition method was assessed qualitatively using a euthanized mouse and an excised human atherosclerotic plaque. Spectral CT measurements of a phantom containing tissue surrogates confirmed the ability to distinguish these materials by the spectroscopic characteristics of their CT number. The assessment of performance potential in terms of information entropy and degrees of freedom indicated that certain sets of up to three materials could be decomposed by the method of constrained least squares. However, there was insufficient information within the data set to distinguish calcium from iron within soft tissues. The quantification of calcium concentration and fat mass fraction within atheroma and mouse equivalent phantoms by spectral CT correlated well with the nominal values (R(2) = 0.990 and R(2) = 0.985, respectively). In the euthanized mouse and excised human atherosclerotic plaque, regions of calcium and fat were appropriately decomposed according to their spectroscopic characteristics. Spectral CT, using the Medipix3 detector and silicon sensor layer, can quantify certain sets of up to three materials using the proposed method of constrained least squares. The system has some ability to independently distinguish calcium, fat, and water, and these have been quantified within phantom equivalents of fatty liver and atheroma. In this configuration, spectral CT cannot distinguish iron from calcium within soft tissues.

  12. Chronic effects of soft drink consumption on the health state of Wistar rats: A biochemical, genetic and histopathological study.

    PubMed

    Alkhedaide, Adel; Soliman, Mohamed Mohamed; Salah-Eldin, Alaa-Eldin; Ismail, Tamer Ahmed; Alshehiri, Zafer Saad; Attia, Hossam Fouad

    2016-06-01

    The present study was performed to examine the effects of chronic soft drink consumption (SDC) on oxidative stress, biochemical alterations, gene biomarkers and histopathology of bone, liver and kidney. Free drinking water of adult male Wistar rats was substituted with three different soft drinks: Coca‑Cola, Pepsi and 7‑Up, for three consecutive months. The serum and organs were collected for examining the biochemical parameters associated with bone, liver and kidney functions. Semi‑quantitative reverse transcription polymerase chain reaction was used to observe the changes in the expression of genes in the liver and kidney, which are associated with oxidative stress resistance. Histopathological investigations were performed to determine the changes in bone, liver and kidney tissues using hematoxylin and eosin stains. SDC affected liver, kidney and bone function biomarkers. Soft drinks increased oxidative stress, which is represented by an increase in malondialdehyde and a decrease in antioxidant levels. SDC affected serum mineral levels, particularly calcium and phosphorus. Soft drinks downregulated the expression levels of glutathione‑S‑transferase and super oxide dismutase in the liver compared with that of control rats. Rats administered Coca‑Cola exhibited a hepatic decrease in the mRNA expression of α2‑macroglobulin compared with rats administered Pepsi and 7‑Up. On the other hand, SDC increased the mRNA expression of α1‑acid glycoprotein. The present renal studies revealed that Coca‑Cola increased the mRNA expression levels of desmin, angiotensinogen and angiotensinogen receptor compared with the other groups, together with mild congestion in renal histopathology. Deleterious histopathological changes were reported predominantly in the bone and liver of the Coca‑Cola and Pepsi groups. In conclusion, a very strict caution must be considered with SDC due to the increase in oxidative stress biomarkers and disruption in the expression of certain genes associated with the bio‑vital function of both the liver and kidney.

  13. Chronic effects of soft drink consumption on the health state of Wistar rats: A biochemical, genetic and histopathological study

    PubMed Central

    ALKHEDAIDE, ADEL; SOLIMAN, MOHAMED MOHAMED; SALAH-ELDIN, ALAA-ELDIN; ISMAIL, TAMER AHMED; ALSHEHIRI, ZAFER SAAD; ATTIA, HOSSAM FOUAD

    2016-01-01

    The present study was performed to examine the effects of chronic soft drink consumption (SDC) on oxidative stress, biochemical alterations, gene biomarkers and histopathology of bone, liver and kidney. Free drinking water of adult male Wistar rats was substituted with three different soft drinks: Coca-Cola, Pepsi and 7-Up, for three consecutive months. The serum and organs were collected for examining the biochemical parameters associated with bone, liver and kidney functions. Semi-quantitative reverse transcription polymerase chain reaction was used to observe the changes in the expression of genes in the liver and kidney, which are associated with oxidative stress resistance. Histopathological investigations were performed to determine the changes in bone, liver and kidney tissues using hematoxylin and eosin stains. SDC affected liver, kidney and bone function biomarkers. Soft drinks increased oxidative stress, which is represented by an increase in malondialdehyde and a decrease in antioxidant levels. SDC affected serum mineral levels, particularly calcium and phosphorus. Soft drinks downregulated the expression levels of glutathione-S-transferase and super oxide dismutase in the liver compared with that of control rats. Rats administered Coca-Cola exhibited a hepatic decrease in the mRNA expression of α2-macroglobulin compared with rats administered Pepsi and 7-Up. On the other hand, SDC increased the mRNA expression of α1-acid glycoprotein. The present renal studies revealed that Coca-Cola increased the mRNA expression levels of desmin, angiotensinogen and angiotensinogen receptor compared with the other groups, together with mild congestion in renal histopathology. Deleterious histopathological changes were reported predominantly in the bone and liver of the Coca-Cola and Pepsi groups. In conclusion, a very strict caution must be considered with SDC due to the increase in oxidative stress biomarkers and disruption in the expression of certain genes associated with the bio-vital function of both the liver and kidney. PMID:27121771

  14. Experimental and analytical study of the DC breakdown characteristics of polypropylene laminated paper with a butt gap condition considering the insulation design of superconducting cable

    NASA Astrophysics Data System (ADS)

    Seo, In-jin; Choi, Won; Seong, Jae-gyu; Lee, Bang-wook; Koo, Ja-yoon

    2014-08-01

    It has been reported that the insulation design under DC stress is considered as one of the critical factors in determining the performance of high-voltage direct current (HVDC) superconducting cable. Therefore, it is fundamentally necessary to investigate the DC breakdown characteristics of the composite insulation system consisting of liquid nitrogen (LN2)/polypropylene-laminated-paper (PPLP). In particular, the insulation characteristics under DC polarity reversal condition should be verified to understand the polarity effect of the DC voltage considering the unexpected incidents taking place at line-commutated-converters (LCC) under service at a DC power grid. In this study, to examine the variation of DC electric field strength, the step voltage and polarity reversal breakdown tests are performed under DC stress. Also, we investigate the electric field distributions in a butt gap of the LN2/PPLP condition considering the DC polarity reversal by using simulation software.

  15. Enterococcus faecium F58, a bacteriocinogenic strain naturally occurring in Jben, a soft, farmhouse goat's cheese made in Morocco.

    PubMed

    Achemchem, F; Martínez-Bueno, M; Abrini, J; Valdivia, E; Maqueda, M

    2005-01-01

    Characterization of Ent F-58 produced by Enterococcus faecium strain F58 isolated from Jben, a soft, farmhouse goat's cheese manufactured without starter cultures. E. faecium strain F58 was isolated because of its broad inhibitory spectrum, including activity against food-borne pathogenic and spoilage bacteria. The antimicrobial substance was produced during the growth phase, with maximum production after 16-20 h of incubation at 30 degrees C, and was stable over a wide pH range (4-8) and at high temperatures (5 min at 100 degrees C). The enterocin was purified to homogeneity using cation exchange and hydrophobic interaction on C-18 and reverse-phase high-performance liquid chromatography. The activity was eluted as two individual active fractions (F-58A and F-58B) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis showed masses of 5210.5 and 5234.3 Da respectively. Both peptides were partially sequenced by Edman degradation, and amino-acid sequencing revealed high similarity with enterocin L50 (I). PCR-amplified fragments containing the structural genes for F-58 A and B were located in a 22-kb plasmid harboured by this strain. We verified that it also holds the structural gene for P-like enterocin. E. faecium strain F58 from Jben cheese, a producer of enterocin L50, exerts an inhibitory effect against strains of genera such as Listeria, Staphylococcus, Clostridium, Brochothrix and Bacillus. Enterocin was characterized according to its functional and biological properties, purification to homogeneity and an analysis of its amino acid and genetic sequences. E. faecium strain F58 is a newly discovered producer of enterocin L50, the biotechnological characteristics of which indicate its potential for application as a protective agent against pathogens and spoilage bacteria in foods.

  16. Dual Salt- and Thermo-Responsive Programmable Bilayer Hydrogel Actuators with Pseudo-Interpenetrating Double-Network Structures.

    PubMed

    Xiao, Shengwei; Zhang, Mingzhen; He, Xiaomin; Huang, Lei; Zhang, Yanxian; Ren, Baiping; Zhong, Mingqiang; Chang, Yung; Yang, Jintao; Zheng, Jie

    2018-06-07

    Development of smart soft actuators is highly important for fundamental research and industrial applications, but has proved to be extremely challenging. In this work, we present a facile, one-pot, one-step method to prepare dual-responsive bilayer hydrogels, consisting of a thermos-responsive poly(N-isopropyl acrylamide) (polyNIPAM) layer and a salt-responsive poly(3-(1-(4-vinylbenzyl)-1H-imidazol-3-ium-3-yl)propane-1-sulfonat) (polyVBIPS) layer. Both polyNIPAM and polyVBIPs layers exhibit a completely opposite swelling/shrinking behavior, where polyNIPAM shrinks (swells) but polyVBIPS swells (shrinks) in salt solution (water) or at high (low) temperatures. By tuning NIPAM:VBIPS ratios, the resulting polyNIPAM/polyVBIPS bilayer hydrogels enable to achieve fast and large-amplitude bidirectional bending in response to temperatures, salt concentrations, and salt types. Such bidirectional bending, bending orientation and degree can be reversibly, repeatedly, and precisely controlled by salt- or temperature-induced cooperative, swelling-shrinking properties from both layers. Based on their fast, reversible, bidirectional bending behavior, we further design two conceptual hybrid hydrogel actuators, serving as a six-arm gripper to capture, transport, and release an object and an electrical circuit switch to turn on-and-off a lamp. Different from the conventional two or multi-step methods for preparation of bilayer hydrogels, our simple, one-pot, one-step method and a new bilayer hydrogel system provide an innovative concept to explore new hydrogel-based actuators through combining different responsive materials that allow to program different stimulus for soft and intelligent materials applications.

  17. Nature versus Nurture: The Origin of Soft Gamma-Ray Repeaters and Anomalous X-Ray Pulsars

    NASA Astrophysics Data System (ADS)

    Marsden, D.; Lingenfelter, R. E.; Rothschild, R. E.; Higdon, J. C.

    2001-03-01

    Soft gamma-ray repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are young and radio-quiet X-ray pulsars that have been rapidly spun-down to slow spin periods clustered in the range 5-12 s. Most of these unusual pulsars also appear to be associated with supernova shell remnants (SNRs) with typical ages less than 30 kyr. By examining the sizes of these remnants versus their ages, we demonstrate that the interstellar media that surrounded the SGR and AXP progenitors and their SNRs were unusually dense compared to the environments around most young radio pulsars and SNRs. We explore the implications of this evidence on magnetar and propeller-based models for the rapid spin-down of SGRs and AXPs. We find that evidence of dense environments is not consistent with the magnetar model unless a causal link can be shown between the development of magnetars and the external interstellar medium. Propeller-driven spin-down by fossil accretion disks for SGRs and AXPs appears to be consistent with dense environments since the environment can facilitate the formation of such a disk. This may occur in two ways: (1) formation of a ``pushback'' disk from the innermost ejecta pushed back by prompt reverse shocks from supernova remnant interactions with massive progenitor wind material stalled in dense surrounding gas or (2) acquisition of disks by a high-velocity neutron stars, which may be able to capture sufficient amounts of comoving outflowing ejecta slowed by the prompt reverse shocks in dense environments.

  18. In vitro screening of potential probiotic activities of selected lactobacilli isolated from unpasteurized milk products for incorporation into soft cheese.

    PubMed

    Coeuret, Valérie; Gueguen, Micheline; Vernoux, Jean Paul

    2004-11-01

    The aim was to select potentially probiotic lactobacilli from 88 strains isolated from unpasteurized milk and cheese products, and to incorporate these bacteria in a viable state into a soft cheese, without changing its quality. The survival of these bacteria was assessed in acidic and bile conditions, after freezing at -80 degrees C. Four strains from unpasteurized Camembert--two Lactobacillus plantarum strains and two Lb. paracasei/casei strains--were identified and typed by PCR and PFGE and were found to display potentially probiotic characteristics in addition to resistance to low pH and bile. These characteristics were resistance to lysozyme, adhesion to CACO-2 cells, antimicrobial effects against common foodborne pathogens (Listeria monocytogenes, Staphylococcus aureus, Salmonella spp., Escherichia coli, innocuity following the ingestion of high doses by mice and appropriate antibiotic susceptibility profiles. The potential of Lb. plantarum strain UCMA 3037 for incorporation into a soft cheese (Pont-l'Eveque registered designation of origin (RDO)) was investigated. This strain grew well and survived in sufficient numbers (more than 10(7) cfu/g throughout the shelf-life of the product) in the cheese. This strain did not change the quality score of the product until the best before date (75 days after manufacture). Thus, unpasteurized Camembert is a natural source of potentially probiotic lactobacilli, which could be used as an additive in the development of potentially probiotic soft cheeses. Further work is required to demonstrate the persistence and efficacy of these strains in the human host upon ingestion.

  19. Occurrence of Cellulose-Producing Gluconacetobacter spp. in Fruit Samples and Kombucha Tea, and Production of the Biopolymer.

    PubMed

    Neera; Ramana, Karna Venkata; Batra, Harsh Vardhan

    2015-06-01

    Cellulose producing bacteria were isolated from fruit samples and kombucha tea (a fermented beverage) using CuSO4 solution in modified Watanabe and Yamanaka medium to inhibit yeasts and molds. Six bacterial strains showing cellulose production were isolated and identified by 16S rRNA gene sequencing as Gluconacetobacter xylinus strain DFBT, Ga. xylinus strain dfr-1, Gluconobacter oxydans strain dfr-2, G. oxydans strain dfr-3, Acetobacter orientalis strain dfr-4, and Gluconacetobacter intermedius strain dfr-5. All the cellulose-producing bacteria were checked for the cellulose yield. A potent cellulose-producing bacterium, i.e., Ga. xylinus strain DFBT based on yield (cellulose yield 5.6 g/L) was selected for further studies. Cellulose was also produced in non- conventional media such as pineapple juice medium and hydrolysed corn starch medium. A very high yield of 9.1 g/L cellulose was obtained in pineapple juice medium. Fourier transform infrared spectrometer (FT-IR) analysis of the bacterial cellulose showed the characteristic peaks. Soft cellulose with a very high water holding capacity was produced using limited aeration. Scanning electron microscopy (SEM) was used to analyze the surface characteristics of normal bacterial cellulose and soft cellulose. The structural analysis of the polymer was performed using (13)C solid-state nuclear magnetic resonance (NMR). More interfibrillar space was observed in the case of soft cellulose as compared to normal cellulose. This soft cellulose can find potential applications in the food industry as it can be swallowed easily without chewing.

  20. [Clinicopathologic characteristics of hemangiopericytoma/solitary fibrous tumor with giant cells].

    PubMed

    Wang, Hai-yan; Fan, Qin-he; Gong, Qi-xing; Wang, Zheng

    2009-03-01

    To study the pathological characteristics, diagnosis and differential diagnoses of hemangiopericytoma-solitary fibrous tumor with giant cells. Pathological characteristics of seven cases of orbital and extraorbital hemangiopericytoma-solitary fibrous tumors with giant cells were evaluated by HE and immunohistochemistry (EnVision method). Two cases were located in the orbit, one of which had recurred. Five cases were located in the extraorbital regions. Histologically, the tumors were well-circumscribed and composed of non-atypical, round to spindle cells with collagen deposition in the stroma. The tumors had prominent vasculatures and in areas, pseudovascular spaces lined by multinucleated giant cells lining which were also present in the stroma. Immunohistochemically, both neoplastic cells and multinucleate giant cells expressed CD34. Seven patients underwent tumor excision and were well and without tumor recurrence upon the clinical follow-up. Hemangiopericytoma-solitary fibrous tumor with giant cells is an intermediate soft tissue tumor. It typically involves the orbital or extraorbital regions. Histologically, the tumor should be distinguished from giant cell fibroblastoma, pleomorphic hyalinzing angiectatic tumor of soft part and angiomatoid fibrous histiocytoma.

  1. High-resolution MRI vessel wall imaging: spatial and temporal patterns of reversible cerebral vasoconstriction syndrome and central nervous system vasculitis.

    PubMed

    Obusez, E C; Hui, F; Hajj-Ali, R A; Cerejo, R; Calabrese, L H; Hammad, T; Jones, S E

    2014-08-01

    High-resolution MR imaging is an emerging tool for evaluating intracranial artery disease. It has an advantage of defining vessel wall characteristics of intracranial vascular diseases. We investigated high-resolution MR imaging arterial wall characteristics of CNS vasculitis and reversible cerebral vasoconstriction syndrome to determine wall pattern changes during a follow-up period. We retrospectively reviewed 3T-high-resolution MR imaging vessel wall studies performed on 26 patients with a confirmed diagnosis of CNS vasculitis and reversible cerebral vasoconstriction syndrome during a follow-up period. Vessel wall imaging protocol included black-blood contrast-enhanced T1-weighted sequences with fat suppression and a saturation band, and time-of-flight MRA of the circle of Willis. Vessel wall characteristics including enhancement, wall thickening, and lumen narrowing were collected. Thirteen patients with CNS vasculitis and 13 patients with reversible cerebral vasoconstriction syndrome were included. In the CNS vasculitis group, 9 patients showed smooth, concentric wall enhancement and thickening; 3 patients had smooth, eccentric wall enhancement and thickening; and 1 patient was without wall enhancement and thickening. Six of 13 patients had follow-up imaging; 4 patients showed stable smooth, concentric enhancement and thickening; and 2 patients had resoluton of initial imaging findings. In the reversible cerebral vasoconstriction syndrome group, 10 patients showed diffuse, uniform wall thickening with negligible-to-mild enhancement. Nine patients had follow-up imaging, with 8 patients showing complete resolution of the initial findings. Postgadolinium 3T-high-resolution MR imaging appears to be a feasible tool in differentiating vessel wall patterns of CNS vasculitis and reversible cerebral vasoconstriction syndrome changes during a follow-up period. © 2014 by American Journal of Neuroradiology.

  2. [Electron microscopic study on the petechial hemorrhagic spots in patients with epidemic hemorrhage fever (EHF)].

    PubMed

    Wang, S Q; Feng, M; Yang, L

    1994-12-01

    EHF viral particles were found in the squamous epithelial cells and capillary endothelial cells of the petechial spots located at the mucous membrane of the soft palate in cases of early stage of severe type EHF by transmission electron microscopy. The viral particles are round or oval in shape, about 100 nm in diameter with a lipid bilayer envelope from which spikes are protruding. The virions matured by budding through the intracytoplasmic membranes into the smooth surfaced vesicles. The morphological characteristics of the virion coincided with the viral particles of Family Bunyaviridae. It was the first time to demonstrate that the squamous epithelial cells of the soft palate is one of the target cells in EHF virus infection and to describe the subcellular morphological evidence of the petechial spots at the soft palate by EM.

  3. Power-law X-ray and gamma-ray emission from relativistic thermal plasmas

    NASA Technical Reports Server (NTRS)

    Zdziarski, A. A.

    1985-01-01

    A common characteristic of cosmic sources is power-law X-ray emission. Extragalactic sources of this type include compact components of active galactic nuclei (AGN). The present study is concerned with a theoretical model of such sources, taking into account the assumption that the power-law spectra are produced by repeated Compton scatterings of soft photons by relativistic thermal electrons. This is one of several possible physical mechanisms leading to the formation of a power-law spectrum. Attention is given to the Comptonization of soft photon sources, the rates of pair processes, the solution of the pair equilibrium equation, and the constraints on a soft photon source and an energy source. It is concluded that the compactness parameters L/R of most of the cosmic sources observed to date lie below the maximum luminosity curves considered.

  4. Interrelation of soft and hard X-ray emissions during solar flares. I - Observations

    NASA Technical Reports Server (NTRS)

    Winglee, R. M.; Kiplinger, A. L.; Zarro, D. M.; Dulk, G. A.; Lemen, J. R.

    1991-01-01

    The interrelation between the acceleration and heating of electrons and ions during impulsive solar flares is determined on the basis of simulataneous observations of hard and soft X-ray emission from the Solar Maximum Mission at high time resolution (6 s). For all the flares, the hard X-rays are found to have a power-law spectrum which breaks down during the rise phase and beginning of the decay phase. After that, the spectrum changes to either a single power law or a power law that breaks up at high energies. The characteristics of the soft X-ray are found to depend on the flare position. It is suggested that small-scale quasi-static electric fields are important for determining the acceleration of the X-ray-producing electrons and the outflowing chromospheric ions.

  5. Power Supply for Variable Frequency Induction Heating Using MERS Soft-Switching High Frequency Inverter

    NASA Astrophysics Data System (ADS)

    Isobe, Takanori; Kitahara, Tadayuki; Fukutani, Kazuhiko; Shimada, Ryuichi

    Variable frequency induction heating has great potential for industrial heating applications due to the possibility of achieving heating distribution control; however, large-scale induction heating with variable frequency has not yet been introduced for practical use. This paper proposes a high frequency soft-switching inverter for induction heating that can achieve variable frequency operation. One challenge of variable frequency induction heating is increasing power electronics ratings. This paper indicates that its current source type dc-link configuration and soft-switching characteristics can make it possible to build a large-scale system with variable frequency capability. A 90-kVA 150-1000Hz variable frequency experimental power supply for steel strip induction heating was developed. Experiments confirmed the feasibility of variable frequency induction heating with proposed converter and the advantages of variable frequency operation.

  6. Soft Tissue Sarcoma, Version 2.2016, NCCN Clinical Practice Guidelines in Oncology.

    PubMed

    von Mehren, Margaret; Randall, R Lor; Benjamin, Robert S; Boles, Sarah; Bui, Marilyn M; Conrad, Ernest U; Ganjoo, Kristen N; George, Suzanne; Gonzalez, Ricardo J; Heslin, Martin J; Kane, John M; Koon, Henry; Mayerson, Joel; McCarter, Martin; McGarry, Sean V; Meyer, Christian; O'Donnell, Richard J; Pappo, Alberto S; Paz, I Benjamin; Petersen, Ivy A; Pfeifer, John D; Riedel, Richard F; Schuetze, Scott; Schupak, Karen D; Schwartz, Herbert S; Tap, William D; Wayne, Jeffrey D; Bergman, Mary Anne; Scavone, Jillian

    2016-06-01

    Soft tissue sarcomas (STS) are rare solid tumors of mesenchymal cell origin that display a heterogenous mix of clinical and pathologic characteristics. STS can develop from fat, muscle, nerves, blood vessels, and other connective tissues. The evaluation and treatment of patients with STS requires a multidisciplinary team with demonstrated expertise in the management of these tumors. The complete NCCN Guidelines for Soft Tissue Sarcoma (available at NCCN.org) provide recommendations for the diagnosis, evaluation, and treatment of extremity/superficial trunk/head and neck STS, as well as intra-abdominal/retroperitoneal STS, gastrointestinal stromal tumor, desmoid tumors, and rhabdomyosarcoma. This manuscript discusses guiding principles for the diagnosis and staging of STS and evidence for treatment modalities that include surgery, radiation, chemoradiation, chemotherapy, and targeted therapy. Copyright © 2016 by the National Comprehensive Cancer Network.

  7. Cross-lagged relationships between workplace demands, control, support, and sleep problems.

    PubMed

    Hanson, Linda L Magnusson; Åkerstedt, Torbjörn; Näswall, Katharina; Leineweber, Constanze; Theorell, Töres; Westerlund, Hugo

    2011-10-01

    Sleep problems are experienced by a large part of the population. Work characteristics are potential determinants, but limited longitudinal evidence is available to date, and reverse causation is a plausible alternative. This study examines longitudinal, bidirectional relationships between work characteristics and sleep problems. Prospective cohort/two-wave panel. Sweden. 3065 working men and women approximately representative of the Swedish workforce who responded to the 2006 and 2008 waves of the Swedish Longitudinal Occupational Survey of Health (SLOSH). N/A. Bidirectional relationships between, on the one hand, workplace demands, decision authority, and support, and, on the other hand, sleep disturbances (reflecting lack of sleep continuity) and awakening problems (reflecting feelings of being insufficiently restored), were investigated by structural equation modeling. All factors were modeled as latent variables and adjusted for gender, age, marital status, education, alcohol consumption, and job change. Concerning sleep disturbances, the best fitting models were the "forward" causal model for demands and the "reverse" causal model for support. Regarding awakening problems, reciprocal models fitted the data best. Cross-lagged analyses indicates a weak relationship between demands at Time 1 and sleep disturbances at Time 2, a "reverse" relationship from support T1 to sleep disturbances T2, and bidirectional associations between work characteristics and awakening problems. In contrast to an earlier study on demands, control, sleep quality, and fatigue, this study suggests reverse and reciprocal in addition to the commonly hypothesized causal relationships between work characteristics and sleep problems based on a 2-year time lag.

  8. Low-Frequency Coherence Break in the Soft X-Ray State of GRS 1915+105

    NASA Technical Reports Server (NTRS)

    Ji, Jian-Feng; Zhang, Shuang-nan; Qu, Jin-Lu; Li, Ti-Pei

    2003-01-01

    We present results from the analysis of X-ray power density spectra and coherence when GRS 1915+105 is in soft states. We use three data sets that belong to mu, phi, and delta classes as found in the work of Belloni et al. We find that the power density spectra appear t o be complex, with several features between 0.01 and 10 Hz. The coherence deviates from unity above a characteristic frequency. We discuss our results from different models. The corona size in the sphere-disk model implied by this break frequency is on the order of 10(exp 4) GM/c(exp 2), which is unphysical. Our results are more consistent with the prediction of the model of a planar corona sustained by magnetic flares, in which the characteristic frequency is associated with the longest timescale of an individual flare, which is about 8 s.

  9. Statistical Properties of SGR J1550-5418 Bursts

    NASA Technical Reports Server (NTRS)

    Gorgone, Nicholas M.

    2010-01-01

    Magnetars are slowly rotating neutron stars with extreme magnetic fields, over 10(exp 15) Gauss. Only few have been discovered in the last 30 years. These sources are dormant most of their lifetimes and become randomly active emitting multiple soft gamma-ray bursts. We present here our results on the temporal analysis of 300 bursts from Soft Gamma Repeater SGR J1550-5418 recorded with the Gamma-ray Burst Monitor (GBM) onboard the Fermi Observatory during its activation on January 22-29, 2009. We employed an un-triggered burst search in the energy range 8-100keV to collect all events from the source, besides the ones that triggered GBM. For the entire sample of bursts we determined their durations, rise and decay times. We study here the statistical properties of these characteristics and discuss how these may help us better understand the physical characteristics of the magnetar model.

  10. [The investigation of formant on different artistic voice].

    PubMed

    Wang, Jianqun; Gao, Xia; Liu, Xiaozhou; Feng, Yulin; Shen, Xiaohui; Yu, Chenjie; Yang, Ye

    2008-08-01

    To explore the characteristic of formant-a very important parameter in the spectrogram of three types of artistic voice (western mode; Chinese mode; Beijing opera). We used MATLAB software to make the short-time Fourier transform and spectrogram analysis on the homeostasis vowel examples of the three types. The western mode had different representation "singer formant" (Fs) based on the voice part; the Chinese mode's notable features were that F1, F2, F3, were continuous and the energy of them changed softly; the Beijing opera had the common representation which was a very wide formant and there was soft transition between formants and various harmonic, besides it showed a similar component like the "Fs" (two formants connected normally). Different artistic voice showed their own characteristics of the formant parameter in the spectrogram, which had important value on the identification, objective evaluation and prediction.

  11. A comparison of two computer-automated semen analysis instruments for the evaluation of sperm motion characteristics in the stallion.

    PubMed

    Jasko, D J; Lein, D H; Foote, R H

    1990-01-01

    Two commercially available computer-automate semen analysis instruments (CellSoft Automated Semen Analyzer and HTM-2000 Motion Analyzer) were compared for their ability to report similar results based on the analysis of pre-recorded video tapes of extended, motile stallion semen. The determinations of the percentage of motile cells by these instruments were more similar than the comparisons between subjective estimates and either instrument. However, mean values obtained from the same sample may still differ by as much as 30 percentage units between instruments. Instruments varied with regard to the determinations of mean sperm curvilinear velocity and sperm concentration, but mean sperm linearity determinations were similar between the instruments. We concluded that the determinations of sperm motion characteristics by subjective estimation, CellSoft Automated Semen Analyzer, and HTM-2000 Motility Analyzer are often dissimilar, making direct comparisons of results difficult.

  12. Neighborhood-Level and Spatial Characteristics Associated with Lay Naloxone Reversal Events and Opioid Overdose Deaths.

    PubMed

    Rowe, Christopher; Santos, Glenn-Milo; Vittinghoff, Eric; Wheeler, Eliza; Davidson, Peter; Coffin, Philip O

    2016-02-01

    There were over 23,000 opioid overdose deaths in the USA in 2013, and opioid-related mortality is increasing. Increased access to naloxone, particularly through community-based lay naloxone distribution, is a widely supported strategy to reduce opioid overdose mortality; however, little is known about the ecological and spatial patterns of the distribution and utilization of lay naloxone. This study aims to investigate the neighborhood-level correlates and spatial relationships of lay naloxone distribution and utilization and opioid overdose deaths. We determined the locations of lay naloxone distribution sites and the number of unintentional opioid overdose deaths and reported reversal events in San Francisco census tracts (n = 195) from 2010 to 2012. We used Wilcoxon rank-sum tests to compare census tract characteristics across tracts adjacent and not adjacent to distribution sites and multivariable negative binomial regression models to assess the association between census tract characteristics, including distance to the nearest site, and counts of opioid overdose deaths and naloxone reversal events. Three hundred forty-two opioid overdose deaths and 316 overdose reversals with valid location data were included in our analysis. Census tracts including or adjacent to a distribution site had higher income inequality, lower percentage black or African American residents, more drug arrests, higher population density, more overdose deaths, and more reversal events (all p < 0.05). In multivariable analysis, greater distance to the nearest distribution site (up to a distance of 4000 m) was associated with a lower count of Naloxone reversals [incidence rate ratio (IRR) = 0.51 per 500 m increase, 95% CI 0.39-0.67, p < 0.001] but was not significantly associated with opioid overdose deaths. These findings affirm that locating lay naloxone distribution sites in areas with high levels of substance use and overdose risk facilitates reversals of opioid overdoses in those immediate areas but suggests that alternative delivery methods may be necessary to reach individuals in other areas with less concentrated risk.

  13. Newborn Coronal Holes Associated with the Disappearance of Polarity Reversal Boundaries (P46)

    NASA Astrophysics Data System (ADS)

    Shelke, R.

    2006-11-01

    rajendra_shelke@yahoo.co.in Coronal holes play an important role in the occurrence of various kinds of solar events. The geomagnetic activity, coronal transients, type II radio bursts, and soft X ray blowouts have shown their strong association with coronal holes (Webb et al., 1978; Shelke and Pande, 1985; Bhatnagar, 1996; Hewish and Bravo, 1986). Recently, Shelke (2006) has linked the onset of interplanetary erupting stream disturbances with the evolutionary changes in the coronal holes. The present study reveals that there exists some physical relationship between the formation of new coronal holes and the disappearance of polarity reversal boundaries with or without the overlying prominences. About 124 new coronal holes are found to emerge at the locations where polarity reversal boundaries existed prior to their disappearance. Among them, nearly 66% and 18% newborn coronal holes have been associated with disappearing prominences and disappearing small unipolar magnetic regions (UMRs) with encircled polarity reversal boundaries respectively. Coronal holes and quiescent prominences are stable solar features that last for many solar rotations. A coronal hole is indicative of a radial magnetic field of a predominant magnetic polarity at the photosphere, whereas solar prominence overlying the polarity reversal boundary straddles both the polarities of a bipolar magnetic region. The new coronal hole emerges on the Sun, owing to the changes in magnetic field configuration leading to the opening of closed magnetic structure into the corona. The mechanism that leads to the eruption of polarity reversal boundaries with or without prominences seems to be interlinked with the mechanism that converts bipolar magnetic regions into unipolar magnetic regions characterizing coronal holes. The fundamental activity for the onset of erupting polarity reversal boundary seems to be the opening of preexisting closed magnetic structures into a new coronal hole, which can support mass motion including erupting prominence.

  14. Innovative diffraction gratings for high-resolution resonant inelastic soft x-ray scattering spectroscopy

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

    Voronov, D.L.; Warwick, T.; Gullikson, E. M.

    2016-07-27

    High-resolution Resonant Inelastic X-ray Scattering (RIXS) requires diffraction gratings with very exacting characteristics. The gratings should provide both very high dispersion and high efficiency which are conflicting requirements and extremely challenging to satisfy in the soft x-ray region for a traditional grazing incidence geometry. To achieve high dispersion one should increase the groove density of a grating; this however results in a diffraction angle beyond the critical angle range and results in drastic efficiency loss. The problem can be solved by use of multilayer coated blazed gratings (MBG). In this work we have investigated the diffraction characteristics of MBGs viamore » numerical simulations and have developed a procedure for optimization of grating design for a multiplexed high resolution imaging spectrometer for RIXS spectroscopy to be built in sector 6 at the Advanced Light Source (ALS). We found that highest diffraction efficiency can be achieved for gratings optimized for 4{sup th} or 5{sup th} order operation. Fabrication of such gratings is an extremely challenging technological problem. We present a first experimental prototype of these gratings and report its performance. High order and high line density gratings have the potential to be a revolutionary new optical element that should have great impact in the area of soft x-ray RIXS.« less

  15. Comparative visualization of digital mammograms on clinical 2K monitor workstations and hardcopy: a contrast detail analysis

    NASA Astrophysics Data System (ADS)

    Torbica, Pavle; Buchberger, Wolfgang; Bernathova, M.; Mallouhi, Ammar; Peer, Siegfried; Bosmans, Hilde; Faulkner, Keith

    2003-05-01

    The purpose of this study was to compare the radiologist`s performance in detecting small low-contrast objects with hardcopy and softcopy reading of digital mammograms. 12 images of a contrast-detail (CD) phantom without and with 25.4 mm, 50.8 mm, and 76.2 mm additional polymethylmetacrylate (PMMA) attenuation were acquired with a caesium iodid/amorphous silicon flat panel detector under standard exposure conditions. The phantom images were read by three independent observers, by conducting a four-alternative forced-choice experiment. Reading of the hardcopy was done on a mammography viewbox under standardized reading conditions. For soft copy reading, a dedicated workstation with two 2K monitors was used. CD-curves and image quality figure (IQF) values were calculated from the correct detection rates of randomly located gold disks in the phantom. The figures were compared for both reading conditions and for different PMMA layers. For all types of exposures, soft copy reading resulted in significantly better contrast-detail characteristics and IQF values, as compared to hard copy reading of laser printouts. (p< 0.01). The authors conclude that the threshold contrast characteristics of digital mammograms displayed on high-resolution monitors are sufficient to make soft copy reading of digital mammograms feasible.

  16. Magnetoelectric coupling characteristics in multiferroic heterostructures with different thickness of nanocrystalline soft magnetic alloy

    NASA Astrophysics Data System (ADS)

    Chen, Lei; Wang, Yao

    2016-05-01

    Magnetoelectric(ME) coupling characteristics in multiferroic heterostructures with different thickness of nanocrystalline soft magnetic alloy has been investigated at low frequency. The ME response with obvious hysteresis, self-biased and dual-peak phenomenon is observed for multiferroic heterostructures, which results from strong magnetic interactions between two ferromagnetic materials with different magnetic properties, magnetostrictions and optimum bias magnetic fields Hdc,opti. The proposed multiferroic heterostructures not only enhance ME coupling significantly, but also broaden dc magnetic bias operating range and overcomes the limitations of narrow bias range. By optimizing the thickness of nanocrystalline soft magnetic alloy Tf, a significantly zero-biased ME voltage coefficient(MEVC) of 14.8mV/Oe (185 mV/cmṡ Oe) at Tf = 0.09 mm can be obtained, which is about 10.8 times as large as that of traditional PZT/Terfenol-D composite with a weak ME coupling at zero bias Hdc,zero. Furthermore, when Tf increases from 0.03 mm to 0.18 mm, the maximum MEVC increases nearly linearly with the increased Tf at Hdc,opti. Additionally, the experimental results demonstrate the ME response for multiferroic heterostructures spreads over a wide magnetic dc bias operating range. The excellent ME performance provides a promising and practicable application for both highly sensitive magnetic field sensors without bias and ME energy harvesters.

  17. Exosomes derived from human adipose mensenchymal stem cells accelerates cutaneous wound healing via optimizing the characteristics of fibroblasts.

    PubMed

    Hu, Li; Wang, Juan; Zhou, Xin; Xiong, Zehuan; Zhao, Jiajia; Yu, Ran; Huang, Fang; Zhang, Handong; Chen, Lili

    2016-09-12

    Prolonged healing and scar formation are two major challenges in the treatment of soft tissue trauma. Adipose mesenchymal stem cells (ASCs) play an important role in tissue regeneration, and recent studies have suggested that exosomes secreted by stem cells may contribute to paracrine signaling. In this study, we investigated the roles of ASCs-derived exosomes (ASCs-Exos) in cutaneous wound healing. We found that ASCs-Exos could be taken up and internalized by fibroblasts to stimulate cell migration, proliferation and collagen synthesis in a dose-dependent manner, with increased genes expression of N-cadherin, cyclin-1, PCNA and collagen I, III. In vivo tracing experiments demonstrated that ASCs-Exos can be recruited to soft tissue wound area in a mouse skin incision model and significantly accelerated cutaneous wound healing. Histological analysis showed increased collagen I and III production by systemic administration of exosomes in the early stage of wound healing, while in the late stage, exosomes might inhibit collagen expression to reduce scar formation. Collectively, our findings indicate that ASCs-Exos can facilitate cutaneous wound healing via optimizing the characteristics of fibroblasts. Our results provide a new perspective and therapeutic strategy for the use of ASCs-Exos in soft tissue repair.

  18. Effect on fan flow characteristics of length and axial location of a cascade thrust reverser

    NASA Technical Reports Server (NTRS)

    Dietrich, D. A.

    1975-01-01

    A series of static tests were conducted on a model fan with a diameter of 14.0 cm to determine the fan operating characteristics, the inlet static pressure contours, the fan-exit total and static pressure contours, and the fan-exit pressure distortion parameters associated with the installation of a partial-circumferential-emission cascade thrust reverser. The tests variables included the cascade axial length, the axial location of the reverser, and the type of fan inlet. It was shown that significant total and static pressure distortions were produced in the fan aft duct, and that some configurations induced a static pressure distortion at the fan face. The amount of flow passed by the fan and the level of the flow distortions were dependent upon all the variables tested.

  19. Metabolic characterization of cultured mammalian cells by mass balance analysis, tracer labeling experiments and computer-aided simulations.

    PubMed

    Okahashi, Nobuyuki; Kohno, Susumu; Kitajima, Shunsuke; Matsuda, Fumio; Takahashi, Chiaki; Shimizu, Hiroshi

    2015-12-01

    Studying metabolic directions and flow rates in cultured mammalian cells can provide key information for understanding metabolic function in the fields of cancer research, drug discovery, stem cell biology, and antibody production. In this work, metabolic engineering methodologies including medium component analysis, (13)C-labeling experiments, and computer-aided simulation analysis were applied to characterize the metabolic phenotype of soft tissue sarcoma cells derived from p53-null mice. Cells were cultured in medium containing [1-(13)C] glutamine to assess the level of reductive glutamine metabolism via the reverse reaction of isocitrate dehydrogenase (IDH). The specific uptake and production rates of glucose, organic acids, and the 20 amino acids were determined by time-course analysis of cultured media. Gas chromatography-mass spectrometry analysis of the (13)C-labeling of citrate, succinate, fumarate, malate, and aspartate confirmed an isotopically steady state of the cultured cells. After removing the effect of naturally occurring isotopes, the direction of the IDH reaction was determined by computer-aided analysis. The results validated that metabolic engineering methodologies are applicable to soft tissue sarcoma cells derived from p53-null mice, and also demonstrated that reductive glutamine metabolism is active in p53-null soft tissue sarcoma cells under normoxia. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  20. Anionic and cationic redox and interfaces in batteries: Advances from soft X-ray absorption spectroscopy to resonant inelastic scattering

    NASA Astrophysics Data System (ADS)

    Yang, Wanli; Devereaux, Thomas P.

    2018-06-01

    Recent advances in battery science and technology have triggered both the challenges and opportunities on studying the materials and interfaces in batteries. Here, we review the recent demonstrations of soft X-ray spectroscopy for studying the interfaces and electrode materials. The focus of this review is on the recently developed mapping of resonant inelastic X-ray scattering (mRIXS) as a powerful probe of battery chemistry with superior sensitivity. Six different channels of soft X-ray absorption spectroscopy (sXAS) are introduced for different experimental purposes. Although conventional sXAS channels remain effective tools for quantitative analysis of the transition-metal states and surface chemistry, we elaborate the limitations of sXAS in both cationic and anionic redox studies. Particularly, based on experimental findings in various electrodes, we show that sXAS is unreliable for studying oxygen redox. We then demonstrate the mRIXS as a reliable technique for fingerprinting oxygen redox and summarize several crucial observations. We conclude that mRIXS is the tool-of-choice to study both the practical issue on reversibility of oxygen redox and the fundamental nature of bulk oxygen states. We hope this review clarifies the popular misunderstanding on oxygen sXAS results of oxide electrodes, and establishes a reliable technique for detecting oxygen redox through mRIXS.

  1. Natural cellulose ionogels for soft artificial muscles.

    PubMed

    Nevstrueva, Daria; Murashko, Kirill; Vunder, Veiko; Aabloo, Alvo; Pihlajamäki, Arto; Mänttäri, Mika; Pyrhönen, Juha; Koiranen, Tuomas; Torop, Janno

    2018-01-01

    Rapid development of soft micromanipulation techniques for human friendly electronics has raised the demand for the devices to be able to carry out mechanical work on a micro- and macroscale. The natural cellulose-based ionogels (CEL-iGEL) hold a great potential for soft artificial muscle application, due to its flexibility, low driving voltage and biocompatibility. The CEL-iGEL composites undergo reversible bending already at ±500mV step-voltage values. A fast response to the voltage applied and high ionic conductivity of membranous actuator is achieved by a complete dissolution of cellulose in 1-ethyl-3-methylimidazolium acetate [EMIm][OAc]. The CEL-iGEL supported cellulose actuator films were cast out of cellulose-[EMIm][OAc] solution via phase inversion in H 2 O. The facile preparation method ensured uniform morphology along the layers and stand for the high ionic-liquid loading in a porous cellulose scaffold. During the electromechanical characterization, the CEL-iGEL actuators showed exponential dependence to the voltage applied with the max strain difference values reaching up to 0.6% at 2 V. Electrochemical analysis confirmed the good stability of CEL-iGEL actuators and determined the safe working voltage value to be below 2.5V. To predict and estimate the deformation for various step input voltages, a mathematical model was proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Consumption of fruit, vegetables, sweets and soft drinks are associated with psychological dimensions of eating behaviour in parents and their 12-year-old children.

    PubMed

    Elfhag, Kristina; Tholin, Sanna; Rasmussen, Finn

    2008-09-01

    We investigated associations between consumption of fruits, vegetables, sweets and soft drinks and the psychological dimensions of eating in parents and their children. The role of the parent's characteristics for their children's food intake was also explored. Food intake patterns were assessed by self-reported consumption of the respective foods. Eating behaviour was measured by the Dutch Eating Behaviour Questionnaire and self-esteem by Harter self-perception scale. The participants were 1441 families (mother, father and their 12-year-old child), and additionally 354 mothers and thirty fathers. Among parents, reported intake of fruit and vegetables were associated with restrained eating, higher self-esteem, and higher education and age. Intake of sweets was related to more external and less restrained eating, and for mothers also emotional eating. Parent's intake of soft drink was foremost related to a younger age, and also weakly associated with psychological characteristics. The food intake of parents was more important for the children's food intake than any other characteristics. However, children's intake of sweets showed clear-cut positive associations with external eating. Psychological dimensions of eating behaviour are associated with patterns of food intake, in particular for consumption of sweets, and are most prominent in the parents. The children's food intake mirrored their parents' intake. Being sensitive to external food cues may increase unhealthy food consumption in our society, whereas more restrained eating may indicate proneness or intention to healthier food choices among parents. Emotional eating may imply a proneness to consume sweets for comfort, in particular among mothers.

  3. The influence of socioeconomic factors and family context on energy-dense food consumption among 2-year-old children.

    PubMed

    Vilela, S; Oliveira, A; Pinto, E; Moreira, P; Barros, H; Lopes, C

    2015-01-01

    Adverse effect on health has been described for a high consumption of energy-dense food, among children and adults. Limited research has been performed among pre-school children. The objective of this study is to evaluate the association between socioeconomic characteristics and family structure, and the consumption of energy-dense food among 2-year-old children. The study sample includes 808 2-year-old children from the Portuguese birth cohort Generation XXI with information on food consumption. Data were obtained from questionnaires administered by interviewers to parents. Based on a food frequency questionnaire, four groups of energy-dense food were defined: soft drinks (sweetened drinks), sweets (chocolate and candies), cakes (creamy and not creamy cakes and sweet pastry) and salty snacks (crisps, pizza and burger). Multinomial logistic regression models (odds ratio and 95% confidence intervals) were fitted to estimate the associations. Intakes of energy-dense food were much lower than in similar aged children in other Westernized countries. Maternal age and education, grandparents' education, household income and maternal occupation were inversely associated with the consumption of energy-dense food, particularly soft drinks and sweets. Children with older siblings were more likely to have a daily consumption of any energy-dense food. Few significant associations were found between socioeconomic characteristics and family structure and consumption of cakes and sweets less than once a week. High socioeconomic characteristics were associated with lower consumption of energy-dense food by 2-year-old children, mainly soft drinks and sweets. This influence is not only from parents' background but also from the preceding generations.

  4. Relationships of personality traits and stress to gingival status or soft-tissue oral pathology: an exploratory study.

    PubMed

    Minneman, M A; Cobb, C; Soriano, F; Burns, S; Schuchman, L

    1995-01-01

    The purpose of this study was to examine the relationships of personality traits and stress with gingival inflammation and with soft-tissue oral pathology. Personality traits of psychoticism (P), extroversion and introversion (E), and neuroticism (N) were measured with Eysenck's personality questionnaire (EPQ). Stress was measured with a modified organizational and individual assessment survey (OIAS) developed by Hendrix. Military recruits from Ft. Leonard Wood, Missouri, were examined for soft-tissue oral pathology and gingival status at weeks one (n = 241) and six (n = 61) of basic combat training (BCT). The EPQ and OIAS were administered to 217 recruits during week six of BCT. A discriminant analysis was used to determine correlations among study variables. Significant correlations (P < .05) were found between personality traits and various measures of tolerance of stress. Little variance was found between groups originally presenting with or without disease. Only physical stress (P < .005) was shown to affect soft-tissue pathology, while gingival inflammation correlated significantly to E scores (P < .02), tolerance to change (P < .02), and anxiety (P < .05). Data support a possible relationship among certain personality traits, stress variables, and gingival inflammation or soft-tissue pathology in recruits with extreme personality characteristics or perception of high physical stress levels in basic combat training.

  5. International application of sugar-sweetened beverage (SSB) taxation in obesity reduction: factors that may influence policy effectiveness in country-specific contexts.

    PubMed

    Jou, Judy; Techakehakij, Win

    2012-09-01

    Sugar-sweetened beverage (SSB) taxation is becoming of increasing interest as a policy aimed at addressing the rising prevalence of obesity in many countries. Preliminary evidence indicates its potential to not only reduce obesity prevalence, but also generate public revenue. However, differences in country-specific contexts create uncertainties in its possible outcomes. This paper urges careful consideration of country-specific characteristics by suggesting three points in particular that may influence the effectiveness of a volume-based soft drink excise tax: population obesity prevalence, soft drink consumption levels, and existing baseline tax rates. Data from 19 countries are compared with regard to each point. The authors suggest that SSB or soft drink taxation policy may be more effective in reducing obesity prevalence where existing obesity prevalence and soft drink consumption levels are high. Conversely, in countries where the baseline tax rate is already considered high, SSB taxation may not have a noticeable impact on consumption patterns or obesity prevalence, and may incur negative feedback from the beverage industry or the general public. Thorough evaluation of these points is recommended prior to adopting SSB or soft drink taxation as an obesity reduction measure in any given country. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. Laser Surgery of Soft Tissue in Orthodontics: Review of the Clinical Trials.

    PubMed

    Seifi, Massoud; Matini, Negin-Sadat

    2017-01-01

    Introduction: Recently, a wide variety of procedures have been done by laser application in orthodontics. Apart from the mentioned range of various treatments, laser has become a tool for many soft tissue surgeries as an alternative to conventional scalpel-based technique during orthodontic treatments in the management of soft tissue. Due to scarce information in the latter subject, this study was designed in order to include clinical trials that included soft tissue ablation by laser in orthodontics. Methods: Literature was searched based on PubMed and Google Scholar databases in 5 years (2010-2015) with English language restriction and clinical trial design. Studies that performed soft tissue application of laser during orthodontic treatment were extracted by the authors. Results: Only eight studies met the inclusion criteria. No significant difference was found between laser ablation and conventional scalpel technique in the matter of treatment outcome. However, few issues remained to clarify the differences in the mentioned procedures. Conclusion: Laser performance can be recommended in case of preceding less bleeding and discomfort during surgical procedure. There are still quandaries among clinical application of scalpel-based surgery in aesthetic region with bracket-bonded teeth. Precaution and knowledge regarding the characteristics of laser beam such as wavelength, frequency, power and timing is extremely needed.

  7. Laser Surgery of Soft Tissue in Orthodontics: Review of the Clinical Trials

    PubMed Central

    Seifi, Massoud; Matini, Negin-Sadat

    2017-01-01

    Introduction: Recently, a wide variety of procedures have been done by laser application in orthodontics. Apart from the mentioned range of various treatments, laser has become a tool for many soft tissue surgeries as an alternative to conventional scalpel-based technique during orthodontic treatments in the management of soft tissue. Due to scarce information in the latter subject, this study was designed in order to include clinical trials that included soft tissue ablation by laser in orthodontics. Methods: Literature was searched based on PubMed and Google Scholar databases in 5 years (2010-2015) with English language restriction and clinical trial design. Studies that performed soft tissue application of laser during orthodontic treatment were extracted by the authors. Results: Only eight studies met the inclusion criteria. No significant difference was found between laser ablation and conventional scalpel technique in the matter of treatment outcome. However, few issues remained to clarify the differences in the mentioned procedures. Conclusion: Laser performance can be recommended in case of preceding less bleeding and discomfort during surgical procedure. There are still quandaries among clinical application of scalpel-based surgery in aesthetic region with bracket-bonded teeth. Precaution and knowledge regarding the characteristics of laser beam such as wavelength, frequency, power and timing is extremely needed. PMID:29263776

  8. Investigation of Stabilised Batu Pahat Soft Soil Pertaining on its CBR and Permeability Properties for Road Construction

    NASA Astrophysics Data System (ADS)

    Mohd Idrus, M. M.; Singh, J. S. M.; Musbah, A. L. A.; Wijeyesekera, D. C.

    2016-07-01

    Soil stabilization by adding materials such as cement, lime and bitumen is one of the effective methods for improving the geotechnical properties of soils [11] Nano-particle is one of the newest additives and many studies about using nano-particle in soil improvement has been done but it was given less attention when soft clay soils stabilization is concerned. To evaluate the strength characteristics of stabilized Batu Pahat soft clay, laboratory investigation on early strength gained by the stabilized soil must be conducted to formulate a suitable and economical mix design [10]. To achieve such purpose, the study examined the effect of NanoClay on the California Bearing Ratio and the Permeability of soft clay. The results gained shows that the Nano-Clay is able to increase the strength of the soft clay [9]. The California Bearing Ratio of the soil is increase significantly where the results for the highest percentage of admixture is 14.4% while the permeability of the soil decreases significantly with increasing Nano-Clay whereby the results of the highest percentage of admixture is 2.0187x10-11 m/s. After doing this research, it is proven that Nano-clay can contribute towards better soil stabilization and enhance the quality of soil as subgrade and foundation at large.

  9. Soft, thin skin-mounted power management systems and their use in wireless thermography

    NASA Astrophysics Data System (ADS)

    Lee, Jung Woo; Xu, Renxiao; Lee, Seungmin; Jang, Kyung-In; Yang, Yichen; Banks, Anthony; Yu, Ki Jun; Kim, Jeonghyun; Xu, Sheng; Ma, Siyi; Jang, Sung Woo; Won, Phillip; Li, Yuhang; Kim, Bong Hoon; Choe, Jo Young; Huh, Soojeong; Kwon, Yong Ho; Huang, Yonggang; Paik, Ungyu; Rogers, John A.

    2016-05-01

    Power supply represents a critical challenge in the development of body-integrated electronic technologies. Although recent research establishes an impressive variety of options in energy storage (batteries and supercapacitors) and generation (triboelectric, piezoelectric, thermoelectric, and photovoltaic devices), the modest electrical performance and/or the absence of soft, biocompatible mechanical properties limit their practical use. The results presented here form the basis of soft, skin-compatible means for efficient photovoltaic generation and high-capacity storage of electrical power using dual-junction, compound semiconductor solar cells and chip-scale, rechargeable lithium-ion batteries, respectively. Miniaturized components, deformable interconnects, optimized array layouts, and dual-composition elastomer substrates, superstrates, and encapsulation layers represent key features. Systematic studies of the materials and mechanics identify optimized designs, including unusual configurations that exploit a folded, multilayer construct to improve the functional density without adversely affecting the soft, stretchable characteristics. System-level examples exploit such technologies in fully wireless sensors for precision skin thermography, with capabilities in continuous data logging and local processing, validated through demonstrations on volunteer subjects in various realistic scenarios.

  10. Soft, thin skin-mounted power management systems and their use in wireless thermography.

    PubMed

    Lee, Jung Woo; Xu, Renxiao; Lee, Seungmin; Jang, Kyung-In; Yang, Yichen; Banks, Anthony; Yu, Ki Jun; Kim, Jeonghyun; Xu, Sheng; Ma, Siyi; Jang, Sung Woo; Won, Phillip; Li, Yuhang; Kim, Bong Hoon; Choe, Jo Young; Huh, Soojeong; Kwon, Yong Ho; Huang, Yonggang; Paik, Ungyu; Rogers, John A

    2016-05-31

    Power supply represents a critical challenge in the development of body-integrated electronic technologies. Although recent research establishes an impressive variety of options in energy storage (batteries and supercapacitors) and generation (triboelectric, piezoelectric, thermoelectric, and photovoltaic devices), the modest electrical performance and/or the absence of soft, biocompatible mechanical properties limit their practical use. The results presented here form the basis of soft, skin-compatible means for efficient photovoltaic generation and high-capacity storage of electrical power using dual-junction, compound semiconductor solar cells and chip-scale, rechargeable lithium-ion batteries, respectively. Miniaturized components, deformable interconnects, optimized array layouts, and dual-composition elastomer substrates, superstrates, and encapsulation layers represent key features. Systematic studies of the materials and mechanics identify optimized designs, including unusual configurations that exploit a folded, multilayer construct to improve the functional density without adversely affecting the soft, stretchable characteristics. System-level examples exploit such technologies in fully wireless sensors for precision skin thermography, with capabilities in continuous data logging and local processing, validated through demonstrations on volunteer subjects in various realistic scenarios.

  11. Soft, thin skin-mounted power management systems and their use in wireless thermography

    PubMed Central

    Lee, Jung Woo; Xu, Renxiao; Lee, Seungmin; Jang, Kyung-In; Yang, Yichen; Banks, Anthony; Yu, Ki Jun; Kim, Jeonghyun; Xu, Sheng; Ma, Siyi; Jang, Sung Woo; Won, Phillip; Li, Yuhang; Kim, Bong Hoon; Choe, Jo Young; Huh, Soojeong; Kwon, Yong Ho; Huang, Yonggang; Paik, Ungyu; Rogers, John A.

    2016-01-01

    Power supply represents a critical challenge in the development of body-integrated electronic technologies. Although recent research establishes an impressive variety of options in energy storage (batteries and supercapacitors) and generation (triboelectric, piezoelectric, thermoelectric, and photovoltaic devices), the modest electrical performance and/or the absence of soft, biocompatible mechanical properties limit their practical use. The results presented here form the basis of soft, skin-compatible means for efficient photovoltaic generation and high-capacity storage of electrical power using dual-junction, compound semiconductor solar cells and chip-scale, rechargeable lithium-ion batteries, respectively. Miniaturized components, deformable interconnects, optimized array layouts, and dual-composition elastomer substrates, superstrates, and encapsulation layers represent key features. Systematic studies of the materials and mechanics identify optimized designs, including unusual configurations that exploit a folded, multilayer construct to improve the functional density without adversely affecting the soft, stretchable characteristics. System-level examples exploit such technologies in fully wireless sensors for precision skin thermography, with capabilities in continuous data logging and local processing, validated through demonstrations on volunteer subjects in various realistic scenarios. PMID:27185907

  12. Resolving the Origin of the Diffuse Soft X-ray Background

    NASA Technical Reports Server (NTRS)

    Smith, Randall K.; Foster, Adam R.; Edgar, Ricard J.; Brickhouse, Nancy S.; Sanders, Wilton T.

    2012-01-01

    In January 1993, the Diffuse X-ray Spectrometer (DXS) measured the first high-resolution spectrum of the diffuse soft X-ray background between 44-80A. A line-dominated spectrum characteristic of a 10(exp 6)K collisionally ionized plasma' was expected but while the observed spectrum was clearly line-dominated, no model would fit. Then in 2003 the Cosmic Hot Interstellar Plasma Spectrometer (CHIPS) launched and observed the diffuse extreme-ultraviolet (EUV) spectrum between 90- 265A. Although many emission lines were again expected; only Fe IX at 171.1A was detected. The discovery of X-rays from comets led to the realization that heavy ions (Z=6-28) in the solar wind will emit soft X-rays as the ions interact via charge exchange with neutral atoms in the heliosphere and geocorona. Using a new model for solar wind charge exchange (SWCX) emission, we show that the diffuse soft X-ray background can be understood as a combination of emission from charge exchange onto the slow and fast solar wind together with a more distant and diffuse hot (10(exp 6)K) plasma.

  13. Seismically-induced soft-sediment deformation structures associated with the Magallanes-Fagnano Fault System (Isla Grande de Tierra del Fuego, Argentina)

    NASA Astrophysics Data System (ADS)

    Onorato, M. Romina; Perucca, Laura; Coronato, Andrea; Rabassa, Jorge; López, Ramiro

    2016-10-01

    In this paper, evidence of paleoearthquake-induced soft-sediment deformation structures associated with the Magallanes-Fagnano Fault System in the Isla Grande de Tierra del Fuego, southern Argentina, has been identified. Well-preserved soft-sediment deformation structures were found in a Holocene sequence of the Udaeta pond. These structures were analyzed in terms of their geometrical characteristics, deformation mechanism, driving force system and possible trigger agent. They were also grouped in different morphological types: sand dykes, convolute lamination, load structures and faulted soft-sediment deformation features. Udaeta, a small pond in Argentina Tierra del Fuego, is considered a Quaternary pull-apart basin related to the Magallanes-Fagnano Fault System. The recognition of these seismically-induced features is an essential tool for paleoseismic studies. Since the three main urban centers in the Tierra del Fuego province of Argentina (Ushuaia, Río Grande and Tolhuin) have undergone an explosive growth in recent years, the results of this study will hopefully contribute to future analyses of the seismic risk of the region.

  14. It's harder to splash on soft solids

    NASA Astrophysics Data System (ADS)

    Howison, Sam; Howland, Christopher; Antkowiak, Arnaud; Castrejon-Pita, Rafael; Oliver, James; Style, Robert; Castrejon-Pita, Alfonso

    2016-11-01

    Droplets splash when they impact dry, flat substrates above a critical velocity that depends on parameters such as droplet size, viscosity and air pressure. By imaging ethanol drops impacting silicone gels of different stiffnesses we show that substrate stiffness also affects the splashing thresh- old. Splashing is reduced or even eliminated: droplets on the softest substrates need over 70% more kinetic energy to splash than they do on rigid substrates. We show that this is due to energy losses caused by deformations of soft substrates during the first few microseconds of impact. We find that solids with Young's moduli < 100kPa reduce splashing, in agreement with simple scaling arguments. Thus materials like soft gels and elastomers can be used as simple coatings for effective splash prevention. Soft substrates also serve as a useful system for testing splash-formation theories and sheet-ejection mechanisms, as they allow the characteristics of ejection sheets to be controlled independently of the bulk impact dynamics of droplets. EPSRC (CJH), John Fell Oxford University Press (OUP) Research Fund (AACP and RWS), The Royal Society (AAC-P).

  15. Soft x-ray streak camera for laser fusion applications

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

    Stradling, G.L.

    This thesis reviews the development and significance of the soft x-ray streak camera (SXRSC) in the context of inertial confinement fusion energy development. A brief introduction of laser fusion and laser fusion diagnostics is presented. The need for a soft x-ray streak camera as a laser fusion diagnostic is shown. Basic x-ray streak camera characteristics, design, and operation are reviewed. The SXRSC design criteria, the requirement for a subkilovolt x-ray transmitting window, and the resulting camera design are explained. Theory and design of reflector-filter pair combinations for three subkilovolt channels centered at 220 eV, 460 eV, and 620 eV aremore » also presented. Calibration experiments are explained and data showing a dynamic range of 1000 and a sweep speed of 134 psec/mm are presented. Sensitivity modifications to the soft x-ray streak camera for a high-power target shot are described. A preliminary investigation, using a stepped cathode, of the thickness dependence of the gold photocathode response is discussed. Data from a typical Argus laser gold-disk target experiment are shown.« less

  16. Design and Characterization of a Soft Robotic Therapeutic Glove for Rheumatoid Arthritis.

    PubMed

    Chua, Matthew Chin Heng; Lim, Jeong Hoon; Yeow, Raye Chen Hua

    2017-07-27

    The modeling and experimentation of a pneumatic actuation system for the development of a soft robotic therapeutic glove is proposed in this article for the prevention of finger deformities in rheumatoid arthritis (RA) patients. The Rehabilitative Arthritis Glove (RA-Glove) is a soft robotic glove fitted with two internal inflatable actuators for lateral compression and massage of the fingers and their joints. Two mechanical models to predict the indentation and bending characteristics of the inflatable actuators based on their geometrical parameters will be presented and validated with experimental results. Experimental validation shows that the model was within a standard deviation of the experimental mean for input pressure range of 0 to 2 bars. Evaluation of the RA-Glove was also performed on six healthy human subjects. The stress distribution along the fingers of the subjects using the RA-Glove was also shown to be even and specific to the finger sizes. This article demonstrates the modeling of soft pneumatic actuators and highlights the potential of the RA-Glove as a therapeutic device for the prevention of arthritic deformities of the fingers.

  17. Aeroelastic considerations for torsionally soft rotors

    NASA Technical Reports Server (NTRS)

    Mantay, W. R.; Yeager, W. T., Jr.

    1986-01-01

    A research study was initiated to systematically determine the impact of selected blade tip geometric parameters on conformable rotor performance and loads characteristics. The model articulated rotors included baseline and torsionally soft blades with interchangeable tips. Seven blade tip designs were evaluated on the baseline rotor and six tip designs were tested on the torsionally soft blades. The designs incorporated a systemmatic variation in geometric parameters including sweep, taper, and anhedral. The rotors were evaluated in the NASA Langley Transonic Dynamics Tunnel at several advance ratios, lift and propulsive force values, and tip Mach numbers. A track sensitivity study was also conducted at several advance ratios for both rotors. Based on the test results, tip parameter variations generated significant rotor performance and loads differences for both baseline and torsionally soft blades. Azimuthal variation of elastic twist generated by variations in the tip parameters strongly correlated with rotor performance and loads, but the magnitude of advancing blade elastic twist did not. In addition, fixed system vibratory loads and rotor track for potential conformable rotor candidates appears very sensitive to parametric rotor changes.

  18. Impact of intra- and extra-osseous soft tissue composition on changes in bone mineral density with weight loss and regain.

    PubMed

    Bosy-Westphal, Anja; Later, Wiebke; Schautz, Britta; Lagerpusch, Merit; Goele, Kristin; Heller, Martin; Glüer, Claus-C; Müller, Manfred J

    2011-07-01

    Recent studies report a significant gain in bone mineral density (BMD) after diet-induced weight loss. This might be explained by a measurement artefact. We therefore investigated the impact of intra- and extra-osseous soft tissue composition on bone measurements by dual X-ray absorptiometry (DXA) in a longitudinal study of diet-induced weight loss and regain in 55 women and 17 men (19-46 years, BMI 28.2-46.8 kg/m(2)). Total and regional BMD were measured before and after 12.7 ± 2.2 week diet-induced weight loss and 6 months after significant weight regain (≥30%). Hydration of fat free mass (FFM) was assessed by a 3-compartment model. Skeletal muscle (SM) mass, extra-osseous adipose tissue, and bone marrow were measured by whole body magnetic resonance imaging (MRI). Mean weight loss was -9.2 ± 4.4 kg (P < 0.001) and was followed by weight regain in a subgroup of 24 subjects (+6.3 ± 2.9 kg; P < 0.001). With weight loss, bone marrow and extra-osseous adipose tissue decreased whereas BMD increased at the total body, lumbar spine, and the legs (women only) but decreased at the pelvis (men only, all P < 0.05). The decrease in BMD(pelvis) correlated with the loss in visceral adipose tissue (VAT) (P < 0.05). Increases in BMD(legs) were reversed after weight regain and inversely correlated with BMD(legs) decreases. No other associations between changes in BMD and intra- or extra-osseous soft tissue composition were found. In conclusion, changes in extra-osseous soft tissue composition had a minor contribution to changes in BMD with weight loss and decreases in bone marrow adipose tissue (BMAT) were not related to changes in BMD.

  19. Soft X-ray and XUV imaging with a charge-coupled device /CCD/-based detector

    NASA Technical Reports Server (NTRS)

    Loter, N. G.; Burstein, P.; Krieger, A.; Ross, D.; Harrison, D.; Michels, D. J.

    1981-01-01

    A soft X-ray/XUV imaging camera which uses a thinned, back-illuminated, all-buried channel RCA CCD for radiation sensing has been built and tested. The camera is a slow-scan device which makes possible frame integration if necessary. The detection characteristics of the device have been tested over the 15-1500 eV range. The response was linear with exposure up to 0.2-0.4 erg/sq cm; saturation occurred at greater exposures. Attention is given to attempts to resolve single photons with energies of 1.5 keV.

  20. Hard X-Rays can BE Used to Visualize Cochlear Soft Tissue Displacements in a Closed Cochlea

    NASA Astrophysics Data System (ADS)

    Richter, C.-P.; Fishman, A.; Fan, L.; Shintani, S.; Rau, C.

    2009-02-01

    Experiments were made at the Advanced Photon Source (APS), Argonne National Laboratory. The APS is a synchrotron radiation source of the third generation, for which the particular characteristic is the highly coherent X-ray radiation. X-rays are generated with an undulator, inserted in a straight section of the storage ring. Images taken with hard X-rays at full field. A video flow algorithm by Lucas and Kanade was used to determine and quantify cochlear soft tissue displacements. The results show that displacements as low as 100 nm could be visualized.

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