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Chellappa Raja S - - 2014
The room temperature stability of 3-3'-diamino-4-4'-azoxyfurazan (DAAF) has been investigated using synchrotron far-infrared, mid-infrared, Raman spectroscopy, and synchrotron x-ray diffraction (XRD) up to 20 GPa. The as-loaded DAAF samples exhibited subtle pressure-induced ordering phenomena (associated with positional disorder of the azoxy 'O' atom) resulting in doubling of the a-axis, to ...
Zhao Xiao-Miao XM Department of Physics, South China University of Technology, Guangzhou 510640, - - 2014
Vibrational properties of isoviolanthrone are investigated by Raman scattering at pressures up to 30.5 GPa and room temperature. A complete characterization of phonon spectra under pressure is given for this material. The onset of a phase transition at 11.0 GPa and the formation of a new phase above 13.8 GPa ...
Ribeiro Mauro C C MC Laboratório de Espectroscopia Molecular, Instituto de Química, Universidade de São Paulo, CP 26077, CEP 05513-970, SP, - - 2014
The glass transition pressure at room temperature, pg, of six ionic liquids based on 1-alkyl-3-methylimidazolium cations and the anions [BF4](-), [PF6](-), and bis(trifluromethanesulfonyl)imide, [NTf2](-), has been obtained from the pressure dependence of the bandwidth of the ruby fluorescence line in diamond anvil cells. Molar volume, Vm(pg), has been estimated by ...
Kosuga Atsuko A Nanoscience and Nanotechnology Research Center, Research Organization for the 21st Century, Osaka Prefecture University , Gakuencho 1-2, Sakai 599-8570, - - 2014
A room-temperature high-pressure synthesis method is proposed as an alternative way to induce nanoscale structural disorder in the bulk thermoelectric CuInTe2 matrix. This disorder stems from the coexistence of distinct domains with different degrees and geometries of disorder at Cu/In cation sites. The lattice thermal conductivity of high-pressure-treated CuInTe2 is ...
Lanzillo Nicholas A NA Departments of Physics, Applied Physics and Astronomy - - 2014
We present a combined first-principles and experimental study of the electrical resistivity in aluminum and copper samples under pressures up to 2 GPa. The calculations are based on first-principles density functional perturbation theory, whereas the experimental setup uses a solid media piston-cylinder apparatus at room temperature. We find that upon ...
Gu Z Y - - 2014
The spectral line shape of spontaneous Rayleigh-Brillouin scattering in CO<sub>2</sub> is studied in a range of pressures. The spectrum is influenced by the bulk viscosity η<sub>b</sub>, which is a relaxation phenomenon involving the internal degrees of freedom of the molecule. The associated relaxation rates can be compared to the frequency ...
Etter Martin M Max Planck Institute for Solid State Research, Stuttgart, - - 2014
Sequential Rietveld refinements were applied on high-pressure synchrotron powder X-ray diffraction measurements of lanthanum ferrite (LaFeO3) revealing two phase transitions on the room-temperature isotherm up to a pressure of 48 GPa. The first structural phase transition of second order occurs at a pressure of 21.1 GPa, changing the space group from Pbnm ...
Laniel Dominique D Laboratoire de physique des solides denses, University of Ottawa, Ottawa, Ontario K1N 6N5, - - 2014
5,5(')-(1H-tetrazolyl)amine (BTA), a nitrogen rich molecular solid has been investigated under compression at room temperature. Powder x-ray diffraction using synchrotron radiation and micro-Raman spectroscopy were carried out to pressures up to 12.9 GPa. BTA conserves the crystalline structure of its room condition phase up to the highest pressure, i.e., an ...
Catafesta Jadna J Institut Charles Gerhardt Montpellier, UMR 5253 CNRS, Université Montpellier 2, 34095 Montpellier Cedex 5, France. - - 2014
Confined H2O molecules act as local probes for depressurization phenomena during the pressure induced amorphisation of faujasite NaX at which the OH stretching frequency first decreases and then increases almost to its room pressure value upon further compression. Pair distribution function (PDF) analysis provides evidence that amorphisation corresponds to a ...
Pereira A L J AL Departamento de Física Aplicada, Instituto de Diseño para la Fabricación y Producción Automatizada, MALTA Consolider Team, Universitat Politècnica de València, 46022 Valencia, - - 2014
We report an experimental and theoretical high-pressure study of the vibrational properties of synthetic monoclinic bismuth oxide (α-Bi2O3), also known as mineral bismite. The comparison of Raman scattering measurements and theoretical lattice-dynamics ab initio calculations is key to understanding the complex vibrational properties of bismite. On one hand, calculations help ...
Whittle Jeff J Primary Care Division, Clement J. Zablocki VA Medical Center, Milwaukee, - - 2014
Peer-led interventions to improve chronic disease self-management can improve health outcomes but are not widely used. Therefore, we tested a peer-led hypertension self-management intervention delivered at regular meetings of community veterans' organizations. We randomized 58 organizational units ("posts") of veterans' organizations in southeast Wisconsin to peer-led vs. professionally delivered self-management ...
McKellar Scott C SC EaStCHEM School of Chemistry, The Centre for Science at Extreme Conditions, University of Edinburgh, Kings Buildings, West Mains Road, Edinburgh, EH9 3JJ, UK. - - 2014
Here we report four post-synthetic modifications, including the first ever example of a high pressure-induced post-synthetic modification, of a porous copper-based metal-organic framework. Ligand exchange with a water ligand at the axial metal site occurs with methanol, acetonitrile, methylamine and ethylamine within a single-crystal and without the need to expose ...
Flin Rhona - - 2014
On April 20th 2010, a large Transocean drilling rig called the Deepwater Horizon was operating in the Gulf of Mexico to drill the Macondo well, for the oil company BP. The job was six weeks behind schedule and $58 million over budget and had not been without difficulty: it was ...
Freedman R R Schlumberger Technology Corp., 110 Schlumberger Drive, Sugar Land, Texas 77478, - - 2014
We discuss an innovative new high-performance apparatus for performing low-field Nuclear Magnetic Resonance (NMR) relaxation times and diffusion measurements on fluids at very high pressures and high temperatures. The apparatus sensor design and electronics specifications allow for dual deployment either in a fluid sampling well logging tool or in a ...
Yilmaz Z Z Departments of Nephrology, Dicle University, Faculty of Medicine, - - 2014
Maintenance of fluid status within an optimal range and accurate assessment of dry weight (DW) is essential in patients on intermittent haemodialysis (HD) treatment. In this study, we aimed to investigate the association of fluid status measured by bioimpedance analysis (BIA) with N-terminal pro-B natriuretic peptide (NT-proBNP), blood pressure and ...
Stankovich Joseph J JJ Department of Chemistry, University of Tennessee, Knoxville, TN, - - 2013
Five methods for controlling the mobile phase flow rate for gradient elution analyses using very high pressure liquid chromatography (VHPLC) were tested to determine thermal stability of the column during rapid gradient separations. To obtain rapid separations, instruments are operated at high flow rates and high inlet pressure leading to ...
Lee Manhee - - 2013
Coalescence of two kinds of pre-processed droplets is necessary to perform chemical and biological assays in droplet-based microfluidics. However, a robust technique to accomplish this does not exist. Here we present a microfluidic device to synchronize the reinjection of two different kinds of droplets and coalesce them, using hydrostatic pressure ...
Stankovich Joseph J - - 2013
Using a column packed with fully porous particles, four methods for controlling the flow rates at which gradient elution runs are conducted in very high pressure liquid chromatography (VHPLC) were tested to determine whether reproducible thermal conditions could be achieved, such that subsequent analyses would proceed at nearly the same ...
Zhao Xiao-Miao - - 2013
Both the vibrational and structural properties of coronene have been investigated upon compression up to 30.5 GPa at room temperature by a combination of Raman scattering and synchrotron x-ray diffraction measurements. The spectroscopic and crystallographic results demonstrate that two pressure-induced structural phase transitions take place at 1.5 GPa and 12.2 ...
Wagner Stefan - - 2013
Abstract Background: Pregnant diabetic patients are often required to self-measure their blood pressure in the waiting room before consultation. Currently used blood pressure devices do not guarantee valid measurements when used unsupervised. This could lead to misdiagnosis and treatment error. The aim of this study was to investigate current use ...
Queirós Rui P - - 2014
Hyperbaric storage (8h) of melon juice (a highly perishable food) at 25, 30 and 37°C, under pressure at 25-150MPa was compared with atmospheric pressure storage (0.1MPa) at the same temperatures and under refrigeration (4°C). Comparatively to the refrigerated condition, hyperbaric storage at 50/75MPa resulted in similar or lower microbial counts ...
Karatas Ahmet - - 2013
Abstract Introduction: Pendrin is an integral membrane protein and plays a key role in extracellular fluid volume and blood pressure control. We aimed to investigate the relationship between pendrin immunostaining intensity in normal and pre-eclamptic placental tissue. Methods: Fifty-six placental tissues, of which 26 were in pre-eclamptic, and 30 were ...
Qajar Ali - - 2013
Porosimetry is a fundamental characterization technique used in the development of new porous materials for catalysis, membrane separation and adsorptive gas storage. Conventional methods like nitrogen and argon adsorption at cryogenic temperatures suffer from slow adsorption dynamics especially for microporous materials. In addition, CO2 the other common probe is only ...
Kalavathi S - - 2013
AlV2O4 is the only spinel compound so far known that exists in the charge ordered state at room temperature. It is known to transform to a charge frustrated cubic spinel structure above 427 ° C. The presence of multivalent V ions in the pyrochlore lattice of the cubic spinel phase brings ...
Cong Rihong - - 2013
β-BiB3O6 was compressed in a diamond anvil cell at room temperature and studied using a combinstion of in situ high-pressure Raman scattering and angle-dispersive synchrotron X-ray diffraction. The results reveal that β-BiB3O6 retains its structure below 9.0 GPa and undergoes a structural phase transition that starts at ∼11.5 GPa and ...
Milly H - - 2013
SUMMARY Minimally invasive dentistry advocates the maintenance of all repairable tooth structures during operative caries management in combination with remineralization strategies. This study evaluated the effect of air-abrasion operating parameters on its cutting efficiency/pattern using bio-active glass (BAG) powder and alumina powder as a control in order to develop its ...
Wang J L - - 2013
We report the dramatic effect of applied pressure and magnetic field on the layered intermetallic compound Pr_{0.5}Y_{0.5}Mn_{2}Ge_{2}. In the absence of pressure or magnetic field this compound displays interplanar ferromagnetism at room temperature and undergoes an isostructural first order magnetic transition (FOMT) to an antiferromagnetic state below 158 K, followed by ...
Milot Emmanuel - - 2013
Despite popular misconceptions, natural selection does operate in modern human populations. New studies even show that changes associated with modernization are deeply reshaping selection pressures and, perhaps, bits of our biological nature.
Yang Zhi - - 2013
The gelatinization of waxy (very low amylose) and high-amylose maize starches by ultra-high hydrostatic pressure (up to 6GPa) was investigated in situ using synchrotron X-ray powder diffraction on samples held in a diamond anvil cell (DAC). The starch pastes, made by mixing starch and water in a 1:1 ratio, were ...
Pawlus S - - 2013
High pressure viscosity and dielectric measurements were carried out on two monohydroxy alcohols, 2-ethyl-1-hexanol and 5-methyl-2-hexanol, at room temperature. Analysis of the dielectric relaxation times versus viscosity revealed the breakdown of the Einstein-Debye relation above some characteristic pressure. The failure of the Einstein-Debye relation is a manifestation of pressure induced ...
Selli Daniele - - 2013
Group-IVa elements silicon and germanium are known for their semiconducting properties at room temperature, which are technologically critical. Metallicity and superconductivity are found at higher pressures only, Ge β-tin (tI4) being the first high-pressure metallic phase in the phase diagram. However, recent experiments suggest that metallicity in germanium is compatible ...
Ye Mu - - 2013
The effects of storage conditions on subsequent high-hydrostatic pressure (HHP) inactivation of Vibrio parahaemolyticus and Vibrio vulnificus in oysters were investigated. Live oysters were inoculated with V. parahaemolyticus or V. vulnificus to ca. 7-8log MPN/g by feeding and stored at varying conditions (i.e., 21 or 35°C for 5h, 4 or ...
Strider David - - 2013
Marfan Syndrome (MFS) is an autosomal dominant, connective tissue disorder that is due to a deficiency in the structural protein, fibrillin. MFS patients are more likely to experience aortic aneurysms and dissections, dislocated lens, and/or severe musculoskeletal deformities than non-MFS patients. Attainment of a longer lifespan in MFS patients is ...
Saeki Keigo - - 2013
BACKGROUND: Previous studies have proposed that higher blood pressure (BP) in winter is an important cause of increased mortality from cardiovascular disease during the winter. Some observational and physiological studies have shown that cold exposure increases BP, but evidence from a randomised controlled study assessing the effectiveness of intensive room ...
Yoshimura Yukihiro - - 2013
We explore the phase behavior of room temperature ionic liquids (RTILs) compressed under high pressure to determine whether they crystallize or hold a liquid state. RTILs have attractive supercooling properties compared with ordinary molecular liquids, which easily become a glassy state without crystallizing at ambient pressure. Thus, phase behavior under ...
Brown S J - - 2013
Acute hypoxia may alter autonomic cardiovascular reflexes during orthostasis. Heart rate variability (HRV), arterial blood pressure (MAP), and respiratory sinus arrhythmia (RSA) were recorded during supine (SUP) and passive head up tilt (HUT) in eight healthy humans, spontaneously breathing either room air or 10 % O(2) in N(2). In the time ...
Yurtseven Hamit - - 2013
We calculate here the Raman frequencies of the lattice modes A(A ( g )), B(B ( 2g )) and C(B ( 1g ) B ( 3g )) as a function of pressure at room temperature for the solid phases (II, III and III') of benzene. This calculation is performed using ...
Shu Kuo-Hsiung KH Division of Nephrology, Department of Medicine, Taichung Veterans General Hospital, Taichung, Taiwan, - - 2013
Background: The blood and membrane contact during dialysis may elicit an immune reaction. The current study looked at the impact of different dialyzers on blood levels of cytokines. Methods: During the first month, randomly selected patients were treated with one dialyzer (PF-170H) and then crossed over to another dialyzer (FLX-18GW) ...
Wen Shiwu - - 2012
Objective: It is uncertain whether preeclampsia (PE) is caused by pre-existing factors or by pregnancy itself. We want to answer this important question in public health by conducting a large pre-conception cohort in China. Methods: A prospective and pre-conception cohort study with a target recruitment of 5000 couples who plan ...
Rozwadowski Tomasz - - 2012
For 4-cyano-3-fluorophenyl 4-butylbenzoate, a glass former giving glass of nematic phase at ambient pressure and after rapid pressurizing, isothermal studies of complex dielectric permittivity vs pressure were performed near room temperature. In the previous isobaric experiment, on cooling the nematic phase two super-Arrhenius α relaxations, ascribed to the reorientations of ...
Li Xianxue - - 2012
Partial pressure suits (PPSs) are used under high altitude, low-pressure conditions to protect the pilots. However, the suit often limits pilot's mobility and work efficiency. The lack of ergonomic data on the effects of PPSs on mobility and performance creates difficulties for human factor engineers and cockpit layout specialists. This ...
Hédoux Alain - - 2012
Low-frequency Raman investigations were carried out upon pressurizing and grinding both crystalline forms of anhydrous caffeine at room temperature. These investigations have led to the detection of metastable states under stress. Upon moderated hydrostatic compression, only form I transform into a metastable state characterized by a Raman band-shape resembling that ...
Dubrovinsky Leonid - - 2012
Since invention of the diamond anvil cell technique in the late 1950s for studying materials at extreme conditions, the maximum static pressure generated so far at room temperature was reported to be about 400 GPa. Here we show that use of micro-semi-balls made of nanodiamond as second-stage anvils in conventional diamond ...
Tarafder Abhijit - - 2012
The pressure and temperature ranges within which supercritical fluid chromatography is operated are generally decided based upon limitations imposed by the instrument or by the stationary phase. Because the maximum pump outlet pressure of most commercial instruments is near 400bar and the maximum temperature at which most chiral stationary phases ...
Tarafder Abhijit - - 2012
The drops of pressure and density along chromatographic columns of different characteristics, eluted with different mixtures of carbon dioxide and methanol was mapped as functions of the column outlet pressure and the operating temperature. This paper extends an earlier report reporting the extent of the pressure and density drops along ...
Mackintosh Natalie - - 2012
Although a high fraction of inspired oxygen (FIO2) could reduce surgical site infection, there is concern it could increase postoperative pulmonary complications, including hypoxemia. Intraoperative positive end-expiratory pressure can improve postoperative pulmonary function. A practical measure of postoperative pulmonary function and the degree of hypoxemia is supplemental oxygen requirement. We ...
Gindlesberger Danielle R - - 2012
A family medicine practice in a large multi-specialty clinic undertook a quality improvement initiative focusing on blood pressure control. Current rooming procedures were reviewed, including obtaining accurate and reliable blood pressures. All rooming staff were instructed how to take an accurate blood pressure and were observed at random over a ...
Steward Jackie A - - 2012
Laboratories throughout the world that perform work with Risk Group 4 Pathogens generally adopt one of two approaches within BSL-4 environments: either the use of positive pressure air-fed suits or using Class III microbiological safety cabinets and isolators for animal work. Within the UK at present, all laboratories working with ...
Bondad J - - 2013
Photodynamic Diagnosis has been proven to improve detection of superficial bladder cancer and improve visualisation of resection margins. The use of 5-aminolevulinic acid as the photosensitising agent has been associated with side effects, specifically hypotension. We aimed to evaluate the effect of oral 5-ALA on the blood pressure in a ...
Randsoe Thomas - - 2012
The standard treatment of altitude decompression sickness (aDCS) caused by nitrogen bubble formation is oxygen breathing and recompression. However, micro air bubbles (containing 79% nitrogen), injected into adipose tissue, grow and stabilize at 25 kPa regardless of continued oxygen breathing and the tissue nitrogen pressure. To quantify the contribution of ...
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