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Guidoboni Giovanna G Department of Mathematical Sciences, Indiana University - Purdue University at Indianapolis, Indianapolis, IN, United States. - - 2014
Retinal hemodynamics plays a crucial role in the pathophysiology of several ocular diseases. There are clear evidences that the hemodynamics of the central retinal artery (CRA) is strongly affected by the level of intraocular pressure (IOP), which is the pressure inside the eye globe. However, the mechanisms through which this ...
Pekel G G Ophthalmology Department, Pamukkale University, Denizli, - - 2014
Choroid, which is the vascular tissue responsible for blood supply to the outer parts of the retina, might be affected by hemodynamic events. We aimed to reveal choroidal thickness and ocular pulse amplitude changes after cardiopulmonary bypass in which gross hemodynamic alterations occur. Forty-two eyes of 42 patients who underwent ...
Freitas Daniele C DC Institut Néel, Centre National de la Recherche Scientifique (CNRS) & Université Joseph Fourier (UJF), 25 Avenue des Martyrs, BP166, F-38042 Grenoble Cedex 9, - - 2014
We determine the pressure phase diagram of the 1111 compounds CaFeAsF and SrFeAsF, up to 20 GPa and down to 4 K by electrical resistivity measurements and the change of structure up to 40 GPa at room temperature. The antiferromagnetic transition temperature, as determined by the derivative peak, shows a minimum at ~5 GPa ...
Bian Kaifu K School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, USA. - - 2014
We investigated pressure-dependent changes in the optical properties of PbS nanocrystal quantum dots (NQD) by combining X-ray scattering and optical absorption spectroscopy in a diamond anvil cell. We discovered that the excitonic absorption peak vanishes as the NQD crystal structure reversibly undergoes the pressure-induced phase transition from rock-salt to orthorhombic ...
Emeterio Nateras Oscar San OS Research Imaging Institute, University of Texas Health Science Center , San Antonio, TX , USA - - 2014
Abstract Purpose: To verify that a visual fixation protocol with cued eye blinks achieves sufficient stability for magnetic resonance imaging (MRI) blood-flow measurements and to determine if choroidal blood flow (ChBF) changes with age in humans. Methods: The visual fixation stability achievable during an MRI scan was measured in five ...
Ertl M M Department of Neurology, Bezirksklinikum Regensburg, University of - - 2014
Ocular color-coded duplex sonography (OCCS), when performed within the safety limits of diagnostic ultrasonography, is an easy noninvasive technique with high potential for diagnosis and therapy in diseases with raised intracranial pressure and vascular diseases affecting the eye. Despite the capabilities of modern ultrasound systems and its scientific validation, OCCS ...
Sonnentag Sabine - - 2014
Lack of psychological detachment from work during off-job time contributes to the increase in employee exhaustion over time. This study examines the reverse causal path from exhaustion to lack of psychological detachment, suggesting that this reverse process may operate within a relatively short time frame. Specifically, we examine if exhaustion ...
Islam Muhammad M aClinical Epidemiology Unit, Department of Community Health Sciences, Aga Khan University, Karachi, Pakistan bHealth Services & Systems Research, Duke-NUS Graduate Medical School, Singapore, Singapore cDivision of Nephrology, Department of Medicine, Tufts Medical Center, Boston, Massachusetts, USA dNational Heart and Lung Institute, Imperial College London, London, UK *N.C. and A.D.H. contributed equally to the writing of the - - 2014
Microcirculatory abnormalities precede the onset of hypertension and may explain its familial nature. We examined the relationship between parental blood pressure (BP) and offspring retinal microvasculature in Pakistani trios [father, mother, and child (aged 9-14 years)]. This is a substudy of a population-based trial of BP reduction. Data were available ...
Kim Shin-Hyun SH Department of Chemical and Biomolecular, Engineering and KINC, KAIST, Daejeon, 305-701, - - 2014
Osmocapsules are microfluidically created to provide a tool for direct measurement of osmotic pressure. As reported by S.-H. Kim and co-workers on page 1155, the osmocapsules enclose standard aqueous solution with an ultrathin polymeric membrane. When many distinct osmocapsules with all different osmolarities are dispersed in an unknown solution, the ...
Hiscox Rachel J RJ *PhD †FRCP, PhD School of Optometry and Vision Sciences (RJH, CP, RVN, KSEE), Cardiff University, Cardiff, Wales, United Kingdom; and All Wales Adult Cystic Fibrosis Centre (IK), University Hospital, Llandough, Cardiff, Wales, United - - 2014
This article aims to describe a case of asymptomatic branch retinal vein occlusion (BRVO) in a patient with cystic fibrosis (CF) and discuss the possible link between the two. A young adult (aged 35 years) with CF who presented for routine ocular examination was found to have a superior temporal ...
Dupas Bénédicte B Ophthalmology Department, Lariboisière Hospital, University Paris Diderot - Sorbonne Paris Cité, AP-HP, Paris, - - 2014
To study spontaneous variations of central macular thickness (CMT) and its relation to blood pressure (BP) in patients with diabetic macular oedema (DME). 23 diabetic patients presenting with DME with a CMT ≥ 260 μm on optical coherence tomography (OCT-3, Carl Zeiss Meditec, CA) were followed every 2 weeks for 3 months. At ...
Lin Hongjun H College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, PR China. Electronic address: - - 2014
A lab-scale membrane bioreactor (MBR) was continuously operated to investigate the membrane fouling. A new membrane fouling mechanism: osmotic pressure mechanism in cake layer filtration process was identified. Osmotic pressure was proposed to stem from the retention of counter-ions in the matrix of biopolymers in cake layer. Through Fourier transform ...
Touboul David D Centre de Reference National pour le Keratocone (CRNK), Centre Hospitalo-Universitaire de Bordeaux, Place Amélie Raba-Léon, Bordeaux, 33000, - - 2014
Purpose: To assess corneal stiffening with Supersonic Shear wave Imaging (SSI) technology in an experimental model of iontophoresis-assisted trans-epithelial corneal collagen cross-linking (I-CXL). Methods: 6 rabbits underwent full central I-CXL in one eye. The contralateral eye served as control. In vivo iontophoresis was used for 10 minutes to perform trans-epithelial ...
Salvetti Massimo M Clinica Medica, Department of Clinical and Experimental Sciences, and Ophthalmology, University of Brescia, Brescia, - - 2014
Wall-to-lumen ratio of retinal arterioles might serve as an in vivo parameter of vascular damage. We analyzed the impact of brachial clinic blood pressure (BP), of central BP, and of 24-hour BP on wall-to-lumen ratio (WLR) of retinal arterioles. In 295 subjects (147 men; age range, 22-72 years; mean age, ...
Jonas Jost B JB Department of Ophthalmology, Heidelberg University, Universitatsmedizin Mannheim, Medical Faculty Mannheim, Mannheim, 68167, - - 2014
Purpose: The venous choroidal blood drains through the superior orbital vein into the intracranial cavernous sinus. The cerebrospinal fluid pressure (CSFP) may thus influence the choroidal venous blood pressure. Since volume and thickness of the choroid depend on its pressure, we tested the hypothesis whether the subfoveal choroidal thickness (SFCT) ...
Tran M K MK Département de la Matière Condensée, University of Geneva, CH-1211 Geneva 4, - - 2014
BiTeI is a giant Rashba spin splitting system, in which a noncentrosymmetric topological phase has recently been suggested to appear under high pressure. We investigated the optical properties of this compound, reflectivity and transmission, under pressures up to 15 GPa. The gap feature in the optical conductivity vanishes above p∼9  GPa and ...
Ott Christian - - 2014
Patients with diabetes mellitus are at increased risk for microvascular complications. Early changes in microcirculation are characterized by hyperperfusion (e.g. in the retina and kidney) and increased pulse wave reflection leading to increased aortic pressure. We investigated the effects of the DPP-4-inhibitor saxagliptin on early retinal microvascular changes. In this ...
Gramlich Oliver W OW Department of Ophthalmology, University Medical Center Mainz, Experimental Ophthalmology, University Medical Center, Langenbeckstr.1, Mainz, 55101, - - 2014
Purpose:An important, yet not exclusive aspect of primary open angle glaucoma is elevated intraocular pressure (IOP) profiles within fluctuations and pressure peaks. The study aimed at establishing minimal-invasive methods for recurring IOP elevation in rats to investigate the impact of IOP dynamics and pathomorphological retinal alterations during and after IOP ...
Koch Edouard E aClinical Investigation Center 503, Centre Hospitalier National des Quinze-Vingts, INSERM and Université Pierre et Marie Curie-Paris6 bPreventive Cardiovascular Unit, Institute of Cardiometabolism and Nutrition, Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris cUniversité Paris-Sud, Hôpital Bicêtre, Assistance Publique-Hôpitaux de Paris, dInstitut Supérieur d'Electronique de Paris, Paris, - - 2014
The wall-to-lumen ratio (WLR) of retinal arteries is a recognized surrogate of end-organ damage due to aging and/or arterial hypertension. However, parietal morphometry remains difficult to assess in vivo. Recently, it was shown that adaptive optics retinal imaging can resolve parietal structures of retinal arterioles in humans in vivo. Here, ...
Smedskjaer Morten M MM Section of Chemistry, Aalborg University, DK-9000 Aalborg, - - 2014
It is known that the coordination number (CN) of atoms or ions in many materials increases through application of sufficiently high pressure. This also applies to glassy materials. In boron-containing glasses, trigonal BO3 units can be transformed into tetrahedral BO4 under pressure. However, one of the key questions is whether ...
Boyer S A E SA MINES ParisTech, CEMEF UMR CNRS 7635, Sophia Antipolis, - - 2014
An original optical high-pressure cell, named CRISTAPRESS, has been especially designed to investigate phase transitions of complex liquids, i.e., polymers, polymer blends, nano-composites, etc. The design of the cell is based on the optical properties of morphological entities through in situ light depolarizing microscopic observations. Pressure up to 200 MPa ...
Fernández José A JA Centre for Experimental Medicine, The Queen's University of Belfast, Belfast, United - - 2014
Pressure myography studies have played a crucial role in our understanding of vascular physiology and pathophysiology. Such studies depend upon the reliable measurement of changes in the diameter of isolated vessel segments over time. Although several software packages are available to carry out such measurements on small arteries and veins, ...
Sun Jiyu J Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University, Changchun 130025, China. - - 2014
In most beetles, the hind wings are thin and fragile; when at rest, they are held over the back of the beetle. When the hind wing unfolds, it provides the necessary aerodynamic forces for flight. In this paper, we investigate the hydraulic mechanism of the unfolding process of the hind ...
Contreras-Martin Y Y Servicio de Neurología, Hospital Universitario Ntra. Sra. de Candelaria, Santa Cruz de Tenerife, España. Electronic address: - - 2013
Idiopathic intracranial hypertension is a disorder characterised by increased intracranial pressure without evidence of an expansive intracranial process or cerebrospinal fluid cytochemical alterations. We reviewed the medical records of patients with idiopathic intracranial hypertension admitted to our hospital between 1999 and 2009 and who met the modified Dandy criteria. We ...
Li Neng - - 2013
We have investigated the mechanism of densification of a nearly perfect continuous random network (CRN) model of amorphous SiO2 (a-SiO2) glass with 1296 atoms and periodic boundary conditions. The model has no under- or over-coordinated atoms and small bond length and bond angle distributions. This near-perfect model is systematically densified ...
Tani Tomofumi - - 2013
PURPOSE. To investigate the regulatory mechanisms responsible for autoregulation of retinal blood flow (RBF) during periods of decreased ocular perfusion pressure (OPP). METHODS. Effects of acute reductions in OPP on RBF were assessed using laser Doppler velocimetry in cats. OPP was decreased from 90 to 40 mmHg by increasing the ...
Pellicer-Porres J - - 2013
We investigate the lattice dynamical and dielectric properties of MgO single crystals and powders by measurements in the mid- and far-infrared frequency region under high pressures, ranging up to 21.7 GPa. The shift of the restrahlen region is used to determine the pressure dependence of the transverse and longitudinal optical modes. The ...
Antonio P-R - - 2013
We report the results of hypertensive treatment over retinal arteriole narrowing in a group of 189 hypertensive patients during a 6-month treatment programme for hypertension. These patients were included in an observational study under clinical practice conditions and analysed using digital photographs of the eye fundus with a previously described ...
Yamaguchi Takeo - - 2013
Human erythrocytes are agglutinated by lectins such as concanavalin A (Con A). The behaviors of agglutinated erythrocytes under pressure are less well understood. Here, we report the effects of erythrocyte agglutination on pressure-induced membrane damages. Small clumps of intact erythrocytes by Con A were dissociated by a pressure of 200MPa. ...
Boddeti Narasimha - - 2013
We created graphene blisters that cover and seal an annular cylinder-shaped microcavity in a SiO2 substrate filled with a gas. By controlling the pressure difference between the gas inside and outside of the microcavity, we switch the graphene membrane between multiple stable equilibrium configurations. We carried out experiments starting from ...
Wang Jin - - 2013
ABSTRACT. We report the dynamic refractive index (RI) change of tissue under a stepped compression load using a custom-built pressure apparatus. Angle-dependent reflectance profiles of biotissue samples are recorded, and the RI values are resolved using the derivative total reflection method. These results are relevant for understanding the mechanism of ...
Risimic Dijana - - 2013
The aim of our study was to examine blood pressure (BP) changes in hypertensive and nonhypertensive patients after intravitreal bevacizumab injections and to assess whether intravitreal bevacizumab carries an associated vascular risk in patients with exudative ocular disease. We also aimed to estimate the influence of gender. The study included ...
Sajedi Parvin P Department of Anesthesia and Critical Care, School of Medicine, Isfahan University of Medical Sciences, Isfahan, - - 2013
The current study aimed to determine preventive effect of 2 percent topical xylocaine on oculocardiac reflex in ophthalmological surgeries except strabismus, including retinal detachment and vitrectomy with scleral buckling under general anesthesia. A randomized controlled clinical trial was carried out on 150 patients aged 18-90 years undergoing ophthalmological surgeries under ...
Moeller J - - 2013
As the production, distribution, and storage of renewable energy based fuels usually are performed under high pressures and as there is a lack of in situ high pressure gas analysis instruments on the market, the aim of this work was to develop a method for in situ high pressure gas ...
Pugh E - - 2013
A compact optical fiber coupler has been developed to allow transmission of light through an optical fiber to and from the high pressure region of a diamond anvil high pressure cell. Despite its small size the coupler has focusing adjustments and optics, which allows the light to be focused precisely ...
Rogers Morgan E ME Department of Ophthalmology, Duke University, Durham, North - - 2013
Pigment epithelium-derived factor (PEDF) regulates blood-retinal barrier function. As a constituent of aqueous humor, the role of PEDF in conventional outflow function is unknown. The goals of the study were to examine the effects of PEDF on barrier function of cultured Schlemm's canal (SC) endothelia and outflow facility in mouse ...
Pang Cheng - - 2013
We present a micro-electro-mechanical systems (MEMS) based Fabry-Perot (FP) sensor along with an optical system-on-a-chip (SOC) interrogator for simultaneous pressure and temperature sensing. The sensor employs a simple structure with an air-backed silicon membrane cross-axially bonded to a 45° polished optical fiber. This structure renders two cascaded FP cavities, enabling ...
Lupton Samantha J SJ University of Western Sydney, School of Medicine, Locked Bag 1797, Penrith, NSW 2751, Australia. - - 2013
Preeclampsia is a leading cause of maternal morbidity and mortality. The degree of maternal cardiovascular dysfunction that precedes the onset of preeclampsia is largely unknown. This prospective cohort study aimed to characterize differences in vivo in retinal microvascular caliber and blood pressure throughout pregnancy in relation to preeclampsia development. Women ...
McMonnies Charles W - - 2013
An examination of how intraocular pressure distending forces on the posterior sclera are an important mechanism in the development and progression of axial myopia has been made. Papers were selected from the results of PubMed (143) and Science Direct (1,398) searches using the key word combinations of 'axial myopia' and ...
Hatami-Marbini Hamed - - 2013
Abstract Purpose: The aim of this study was to characterize swelling pressure-thickness, swelling pressure-hydration and hydration-thickness relations of porcine cornea. Methods: Mechanical compression tests and free swelling experiments were performed on porcine cornea. A rheometer (DHR-2, TA Instruments) with a thermally controlled fluid chamber filled with 0.9% NaCl solution was ...
van der Houwen E B - - 2013
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 ...
Katsuno Chikara - - 2013
Polymer membranes comprising slide-ring gels with movable cross-links exhibit a nonlinear pressure-dependence in the fluidic flow rate. The proportional constant between the flow rate and pressure significantly changes at a critical pressure. The slide-ring gels are promising polymer membrane materials, which would allow for the on-off control of fluid permeability ...
Mesman R J - - 2013
With the development of Cryo Electron Microscopy Of Vitreous Sections (CEMOVIS), imaging cells in a close to native state has become a reality. However with the commonly used carriers for high-pressure freezing and cryo-sectioning, adherent grown cells either need to be detached from their substrate. Here a new method is ...
Gómez-Martínez Rodrigo - - 2013
The ability to measure pressure changes inside different components of a living cell is important, because it offers an alternative way to study fundamental processes that involve cell deformation. Most current techniques such as pipette aspiration, optical interferometry or external pressure probes use either indirect measurement methods or approaches that ...
Auth Thorsten - - 2013
The fluctuation pressure of a lipid-bilayer membrane is important for the stability of lamellar phases and the adhesion of membranes to surfaces. In contrast to many theoretical studies, which predict a decrease of the pressure with the cubed inverse distance between the membranes, Freund suggested very recently a linear inverse ...
Rose William C - - 2013
A mathematical model of whole body and cerebral hemodynamics is a useful tool for investigating visual impairment and intracranial pressure (VIIP), a recently described condition associated with space flight. VIIP involves loss of visual acuity, anatomical changes to the eye, and, usually, elevated cerebrospinal fluid pressure. Loss of visual acuity ...
Wachtel Lee Elizabeth - - 2013
We present a 12-year-old autistic boy who underwent electroconvulsive therapy (ECT) for intractable self-injury toward his head and eyes in the context of acute bilateral retinal detachment and reparative surgery. The patient received 3 ECTs before retinal reattachment surgery, and resumed ECT 2 weeks postoperatively. Bilateral intraocular pressures were monitored ...
Sng Chelvin C A - - 2013
To examine the effect of blood pressure (BP) on retinal vascular fractal dimension (Df), a measure of microvascular network complexity and density in a multiethnic cohort. A population-based study of 3876 Chinese, Malay and Indian participants in Singapore. Retinal Df was measured using a computer-based program from digital retinal photographs. ...
Willmann Gabriel - - 2013
PURPOSE: This study aimed to quantify the impact of exposure to high altitude on individual layers of the cornea in regard to central corneal thickness and the geometry of the anterior chamber angle. This work is related to the Tübingen High Altitude Ophthalmology (THAO) study. METHODS: Anterior segment spectral domain ...
Shiga Yukihiro - - 2013
Abstract Purpose: To investigate, using laser speckle flowgraphy (LSFG), the autoregulation of ocular blood flow (BF) in response to posture change. Methods: This study comprised 20 healthy volunteers (mean age 30.0 ± 8.5). The mean blur rate (MBR) of the ocular circulation in the subjects was assessed in both a sitting and ...
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