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De Swaef Tom T Department of Applied Ecology and Environmental Biology, Laboratory of Plant Ecology, Ghent University, Ghent, Belgium. - - 2013
Upward water movement in plants via the xylem is generally attributed to the cohesion-tension theory, as a response to transpiration. Under certain environmental conditions, root pressure can also contribute to upward xylem water flow. Although the occurrence of root pressure is widely recognized, ambiguity exists about the exact mechanism behind ...
Makhsous Mohsen - - 2012
The aim of this study was to investigate the effect of five chair designs on interface pressure distribution and tissue perfusion in the buttock-thigh region. Prolonged sitting has been found to contribute to the symptoms of work-related low back pain. Studies have found that chair design affects users' sitting posture ...
de Gregorio Cesar - - 2013
The purpose of this investigation was to determine the effect that apical preparation size and preparation taper have on the volume of irrigant delivered at the working length for different canal curvatures using apical negative pressure irrigation. One hundred fifty-five human teeth (55 maxillary canines and 100 mandibular molars) were ...
Carlsson Philip T M - - 2012
Recent studies have suggested that the reaction of stabilised Criegee Intermediates (CIs) with sulfur dioxide (SO(2)), leading to the formation of a carbonyl compound and sulfur trioxide, is a relevant atmospheric source of sulfuric acid. Here, the significance of this pathway has been examined by studying the formation of gas ...
Li H - - 2012
We studied the pressure stability of disulphide bridge mutants of Trichoderma reesei XYNII at 500-5000 bar. The inactivation of XYNII and its mutants was strongest above 4000 bar. The pressure stability correlated with the thermostability order of the XYNII mutants, indicating that the stabilising mutations in protein regions important for ...
Cossi Maurizio - - 2012
The adsorption isotherms of methane in four micro- and mesoporous materials, based on the diamond structure with (poly)phenyl chains inserted in all the C-C bonds, have been simulated with Grand Canonical Monte Carlo technique. The pressure range was extended above 250 bar and the isotherms were computed at 298, 313 ...
Koo Juny - - 2012
Total internal reflection fluorescence (TIRF) spectroscopy is a surface sensitive technique that is widely used to characterize the structure and dynamics of molecules at planar liquid-solid interfaces. In particular, biomolecular systems, such as protein adsorbates and lipid membranes can easily be studied by TIRF spectroscopy. Applying pressure to molecular systems ...
Durães L - - 2012
Nanostructured silica based xerogels and aerogels are prepared by sol-gel technology, using methyltrimethoxysilane as precursor. The influence of the drying method and conditions on the microstructure of the obtained materials is investigated, since the drying stage has a critical influence on their porosity. Two types of drying methods were used: ...
Bian Kaifu - - 2012
We investigated the structural stability of colloidal PbS nanocrystals (NCs) self-assembled into superlattice (SL) allotropes of either face-centered cubic (fcc) or body-centered cubic (bcc) symmetry. Small angle-X-ray scattering (SAXS) analysis showed that NCs are packed more densely in the bcc than in fcc SL, which illustrates the relationship between the ...
Weyand Birgit - - 2012
We present a laminar flow reactor for bone tissue engineering that was developed based on a computational fluid dynamics model. The bioreactor design permits a laminar flow field through its specific internal shape. An integrated bypass system that prevents pressure build-up through bypass openings for pressure release allows for a ...
Schroer Martin A - - 2012
Using small-angle X-ray scattering data of concentrated solutions of the protein lysozyme taken at different pressures and temperatures, the isothermal pressure derivative and the isobaric temperature derivative of the structure factor S(q) were determined. The pressure derivative of S(q) allows us to test various models for the triplet correlation function ...
Tse John S - - 2012
We offer our viewpoint on the nature of amorphous ices produced by pressurization of crystalline ice Ih and the inter-relationship between them from an atomistic perspective. We argue that the transformation of high density amorphous (HDA) ice from crystalline ice is due to a mechanical process arising from the instability ...
Wilding Martin - - 2012
The magnesium silicate system is an important geophysical analogue and neutron diffraction data from glasses formed in this system may also provide an initial framework for understanding the structure-dependent properties of related liquids that are important during planetary formation. Neutron diffraction data collected in situ for a single composition (38 ...
Santamarı́a-Pérez David - - 2012
Angle-dispersive X-ray diffraction measurements have been performed in acanthite, Ag(2)S, up to 18 GPa in order to investigate its high-pressure structural behavior. They have been complemented by ab initio electronic structure calculations. From our experimental data, we have determined that two different high-pressure phase transitions take place at 5 and ...
Cao Kun-Fang - - 2012
Ecology Letters (2012) ABSTRACT: Grasses such as bamboos can produce upright stems more than 30 m tall, yet the processes that constrain plant height in this important group have never been investigated. Air embolisms form commonly in the water transport system of grasses and we hypothesised that root pressure-dependent refilling these ...
Flacau Roxana - - 2012
A combined experimental and theoretical study of hydrogen-rich ammonium borohydride (NH(4)BH(4)) subjected to pressures up to 10 GPa indicates two phase transitions, detected by synchrotron radiation powder X-ray diffraction, Raman spectroscopy and Car-Parrinello molecular dynamics calculations, at 1.5 and 3.4 GPa. The ambient pressure, face-centred cubic phase of NH(4)BH(4) transforms ...
Imamura Hiroshi - - 2012
It is widely accepted that pressure affects the structure and dynamics of proteins; however, the underlying mechanism remains unresolved. Our previous studies have investigated pressure effects on fundamental secondary structural elements using model peptides, because these peptides represent a basis from which to understand pressure effects on more complex structures. ...
Li Xiaohong - - 2012
We demonstrate that the structural transition of ZnS nanoparticles from sphalerite to wurtzite is influenced by high pressures and temperatures. Under the pressure of 1 GPa, the structural transition of ZnS nanoparticles commences at 250 degrees C, much lower than that 400-500 degrees C for ZnS nanoparticles under normal pressures. ...
Tian Bian - - 2012
This paper reports the design and analysis of a type of piezoresistive pressure sensor for micro-pressure measurement with a cross beam-membrane (CBM) structure. This new silicon substrate-based sensor has the advantages of a miniature structure and high sensitivity, linearity, and accuracy. By using the finite element method to analyze the ...
Friedrich Alexandra - - 2012
The high-pressure behaviour of Bi(2)Fe(4)O(9) was analysed by in situ powder and single-crystal x-ray diffraction and Raman spectroscopy. Pressures up to 34.3(8) GPa were generated using the diamond anvil cell technique. A reversible phase transition is observed at approximately 6.89(6) GPa and the high-pressure structure is stable up to 26.3(1) GPa. At higher pressures ...
Kono Yoshio - - 2012
An integration of multi-angle energy-dispersive x-ray diffraction and ultrasonic elastic wave velocity measurements in a Paris-Edinburgh cell enabled us to simultaneously investigate the structures and elastic wave velocities of amorphous materials at high pressure and high temperature conditions. We report the first simultaneous structure and elastic wave velocity measurement for ...
Cui Wen - - 2012
High-pressure Raman studies have been carried out on single crystalline C(60)(Fc)(2) nanosheets up to 25.4 GPa. Our results show that the charge transfer between Fc (ferrocene) and C(60) increases in the low-pressure range. Above 5 GPa, C(60) molecules start to form a chainlike polymer structure, and this polymerization is reversible ...
Hinzmann Andreas - - 2012
We investigated the structure of liquid SnTe at high pressures up to 8.2 GPa by energy-dispersive x-ray diffraction. On melting at low pressures, the crystalline B1 structure changed into not B1-like but distorted-B1-like local structure. We also found that the structure changes at around 1.6-3.3 GPa. At high pressures, the bond angle ...
Lin Chuanlong - - 2012
Structural stability of the perovskite-type GdMnO(3) has been investigated by the synchrotron angle-dispersive x-ray diffraction technique up to 63 GPa in a diamond anvil cell. GdMnO(3) stays in an orthorhombic structure but undergoes an isostructural phase transition with ∼5% volume reduction at 50 GPa. In the parent orthorhombic phase, the compressions along ...
Nagae Takayuki T Department of Biotechnology, Graduate School of Engineering, Nagoya University, - - 2012
Organisms living in deep seas such as the Mariana Trench must be adapted to the extremely high pressure environment. For example, the 3-isopropylmalate dehydrogenase from the obligate piezophile Shewanella benthica DB21MT-2 (SbIPMDH) remains active in extreme conditions under which that from the land bacterium S. oneidensis MR-1 (SoIPMDH) becomes inactivated. ...
Colas de la Noue A - - 2012
In this article, an original non-thermal process to inactivate dehydrated bacterial spores is described. The use of gases such as nitrogen or argon as transmission media under high isostatic pressure led to an inactivation of over 2 logs CFU/g of Bacillus subtilis spores at 430 MPa, room temperature, for a 1 min treatment. A ...
Martinez-Canales Miguel - - 2012
Phases of carbon are studied up to pressures of 1 petapascal (PPa) using first-principles density-functional-theory methods and a structure searching algorithm. Our extensive search over the potential energy surface supports the sequence of transitions diamond→BC8→simple cubic under increasing pressure found in previous theoretical studies. At higher pressures we predict a ...
Lu Xin - - 2012
We use heat-capacity measurements as a function of field rotation to identify the nodal gap structure of CeIrIn_{5} at pressures to 2.05 GPa, deep inside its superconducting dome. A fourfold oscillation in the heat capacity at 0.3 K is observed for all pressures, but with its sign reversed between 1.50 and 0.90 GPa. ...
Stoetzer Marcus - - 2012
Aim. To measure and validate the permeability of pressure changes in correlation to different root filling techniques. Methods. Eighty extracted single-rooted teeth were randomly assigned to one of eight groups of ten teeth. Following standardized instrumentation and irrigation, root canal fillings were performed using either cold lateral condensation, a warm ...
Zmudzki Jarosław - - 2012
The results of previous studies on the pressures beneath the mucous membrane-supported dentures are contrary to the prevailing pain sensations and discomfort reported in practice. In this work, a FEM analysis of large displacements was used for calculation of the contact stresses beneath a lower denture that accompany destabilization under ...
Kwon Ronald Y - - 2012
Interstitial fluid flow (IFF) is a potent regulatory signal in bone. During mechanical loading, IFF is generated through two distinct mechanisms that result in spatially distinct flow profiles: poroelastic interactions within the lacunar-canalicular system, and intramedullary pressurization. While the former generates IFF primarily within the lacunar-canalicular network, the latter generates ...
Ong Frank S - - 2012
-Angiotensin-converting enzyme (ACE) is composed of the N- and C-terminal catalytic domains. To study the role of the ACE domains in the inflammatory response, N-knockout (KO) and C-KO mice, models lacking 1 of the 2 ACE domains, were analyzed during angiotensin II-induced hypertension. At 2 weeks, N-KO mice have systolic ...
Zhang C C - - 2011
The cubic Gd2O3:Eu3+ nanorods were synthesized by a hydrothermal method. The SEM image indicated the nanorods with diameter of 30-35 nm and length of 200-500 nm. The structural stability of Gd2O3:Eu3+ nanorods was investigated by in situ high pressure luminescence and Raman spectra up to 18.9 GPa at room temperature. ...
Matthes Kai - - 2011
BACKGROUND: A novel, over-the-scope clip (OTSC) system may be suitable for closure of various GI perforations. The strength and maximum diameter of closure for a single OTSC, however, are unknown. OBJECTIVE: To determine the maximum closure capacity (diameter) and pressure threshold for a single OTSC. DESIGN: Prospective ex-vivo study. SETTING: ...
Fansa Ashraf M AM Hospital for Special Surgery, 523 E 72nd Street, New York, NY 10021, - - 2011
Autologous osteochondral transplantation procedures provide hyaline cartilage to the site of cartilage repair. It remains unknown whether these procedures restore native contact mechanics of the ankle joint. This study was undertaken to characterize the regional and local contact mechanics after autologous osteochondral transplantation of the talus. Controlled laboratory study. Ten ...
Dasmeh Pouria - - 2011
This work merges a large set of previously reported thermochemical data for myoglobin (Mb) mutants with a physiological model of O(2)-transport and -storage. The model allows a quantification of the functional proficiency of myoglobin (Mb) mutants under various physiological conditions, i.e. O(2)-consumption rate resembling workload, O(2) partial pressure resembling hypoxic ...
Guo Ting - - 2011
With 30 g glucose/l as carbon source, Clostridium beijerinckii ART124, a mutant created by atmospheric pressure glow discharge, produced 13.7 g total solvent/l (containing 3.1 g acetone/l, 10.4 g butanol/l and 0.2 g ethanol/l) in 72 h. The mutant could also use sucrose or xylose or a mixture of glucose/xylose/arabinose with nearly equal yields.
Charoenwong Duangkamol - - 2011
This work investigated the role of rpoS in the development of increased cell envelope resilience and enhanced pressure resistance in stationary-phase cells of Escherichia coli. Loss of both colony-forming ability and membrane integrity, measured as uptake of propidium iodide (PI), occurred at lower pressures in E. coli BW3709 (rpoS) than ...
Thapa Suman S - - 2011
PURPOSE: The purpose of the study was to evaluate the characteristics of central corneal thickness and its association with age, sex, and intraocular pressure in a Nepalese population. PATIENTS AND METHODS: The study design was a cross-sectional, population-based survey. Two thousand three hundred thirty patients aged 40 years and older ...
Pfenninger Lukas - - 2011
The authors conducted a morphology analysis of filtering blebs with anterior segment optical coherence tomography (AS-OCT) in patients shortly after trabeculectomy to find further criteria for success or failure of a filtering bleb. Thirty-seven patients (43 eyes) who had recently (<2 years) undergone trabeculectomy were measured 1 to 4 times ...
Conde M Miñones - - 2011
Mixed monolayers of poly(methyl methacrylate) (PMMA), the main component of hard contact lenses, and dipalmitoyl phosphatidyl choline (DPPC), a characteristic phospholipidic constituent of ocular tear films, were selected as an in vitro model in order to observe the behavior of contact lenses on the eye. Using Langmuir monolayer and Brewster ...
Hariprasad Seenu M - - 2011
To test a novel hydrogel sealant to secure sutureless sclerotomies under variable intraocular pressure conditions. In cadaver eyes, 23- and 20-gauge (G) sclerotomies were constructed. Sixteen 23-G beveled sclerotomies were constructed in 4 eyes: 8 of the incisions were treated with hydrogel sealant, while 8 were left bare. All sclerotomies ...
Lei Yuan - - 2011
Mice are commonly used in glaucoma research, but relatively little is known about aqueous outflow dynamics in the species. To facilitate future use of the mouse as a model of aqueous humor outflow, several fundamental physiological parameters were measured in the mouse eye. Eyes from adult mice of either sex ...
Kaeser Pierre-François - - 2011
We report a 14-year-old boy who presented with vision loss secondary to peripapillary neovascular membrane (PPNVM) as the initial and only symptom of papilledema secondary to idiopathic intracranial hypertension. After one lumbar puncture, visual acuity progressively recovered during the course of 1 week and further improved with the administration of ...
Yu Kehan - - 2011
Carbon nanowalls (CNWs), two-dimensional "graphitic" platelets that are typically oriented vertically on a substrate, can exhibit similar properties as graphene. Growth of CNWs reported to date was exclusively carried out at a low pressure. Here, we report on the synthesis of CNWs at atmosphere pressure using "direct current plasma-enhanced chemical ...
Zinn Pascal O - - 2011
Posterior reversible leukoencephalopathy syndrome refers to a constellation of neurologic symptoms related to temporary white matter changes. The disease typically presents in the context of an abrupt and drastic elevation in blood pressure (>180/110 mmHg). We report an unusual case of posterior reversible leukoencephalopathy syndrome in a post-operative setting, with ...
Stamper Robert L - - 2011
Doctors have not always associated elevated intraocular pressure with the vision loss from glaucoma. Although several individuals appear to have noted firmness of the eye in this condition as far back as the 10th century, elevated intraocular pressure was not routinely assessed until the latter part of the 19th century. ...
Olali C - - 2011
Purpose: To evaluate the safety and efficacy of timolol 0.5%/travoprost 0.004% combination (duotrav) as observed in primary open-angle glaucoma (POAG), ocular hypertension (OHT) and normal tension glaucoma (NTG) in real-life conditions. Materials and Methods: Patients with uncontrolled intraocular pressure (IOP) on other medication and no contraindication to β-blockers were switched ...
Vetter Jan M - - 2010
PURPOSE:To compare the course of intraocular pressure (IOP) during corneal flap preparation using four different femtosecond lasers in porcine globes. METHODS:Forty-eight (12 in each group) enucleated globes were successfully cannulated through the optic nerve. Intraocular pressure was measured continuously through the cannula during a normal lamellar flap creation (regular procedure) ...
Sigmundsson Freysteinn - - 2010
Gradual inflation of magma chambers often precedes eruptions at highly active volcanoes. During such eruptions, rapid deflation occurs as magma flows out and pressure is reduced. Less is known about the deformation style at moderately active volcanoes, such as Eyjafjallajökull, Iceland, where an explosive summit eruption of trachyandesite beginning on ...
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