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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 ...
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 ...
Wang Jin - - 2013
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 mechanical ...
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 ...
Rostocki A J - - 2013
This paper presents measurements of sound velocity and attenuation in olive oil, with known chemical composition, as a function of pressure, within the range of pressure up to 0.7 GPa. Dependencies of sound velocity, relative ultrasonic wave attenuation, volume, and adiabatic compressibility on pressure show discontinuities. This proves the existence of ...
Abe Fumiyoshi - - 2013
High hydrostatic pressure has a profound physiological impact on lipid membranes, primarily resulting in tighter packing and restriction of acyl-chain motion. To fulfill membrane protein functions in high-pressure environments, deep-sea organisms possess specialized cell membranes. Although the effects of high-pressure on model membranes have been investigated in great detail, high-pressure-induced ...
Stodtmeister Richard - - 2013
PURPOSE: The pressure in the central retinal vein (CRVP) has been shown to be higher in glaucoma patients than in controls. Until now, these measurements have been performed in arbitrary units or in units of ophthalmodynamometric force. In this study, a contact lens dynamometer calibrated in mmHg was used to ...
Torres Felipe Soares - - 2013
OBJECTIVE: Abnormalities in retinal vessels are frequent, but its association with findings in other vascular sites has been scarcely investigated. This study aimed to examine the association between ultrasound-measured carotid intima-media thickness (IMT) and retinal arteriolar and venular diameters, in hypertensive patients. METHODS: In this cross-section study, 173 hypertensive patients ...
Levasseur Steve D - - 2013
PURPOSE:: To evaluate the effects and safety of travel by land through high mountainous elevations after surgery in patients who have undergone pars plana vitrectomy with intraocular gas. METHODS:: A retrospective cohort study of 75 patients post pars plana vitrectomy with intraocular gas who traveled by land through mountain elevations ...
Mochizuki Dai - - 2013
The accurate and high-resolution measurement of surface pressure is achieved by a pressure/ temperature-sensitive composite paint (bi-PSP), whereas the pressure-sensitive dye photodegraded the temperature sensitive dye in close arrangement of both dyes. In the present study, an attempt was made to synthesize a homogeneous bi-PSP membrane without light-induced degradation of ...
Feke Gilbert T - - 2013
Abstract Purpose: To assess whether dorzolamide 2%-timolol 0.5% (D/T) and/or brimonidine 0.2%-timolol 0.5% (B/T) alters retinal vascular autoregulation (RVA) and seated ocular perfusion pressure (sOPP) in primary open angle glaucoma (POAG) patients who demonstrate retinal vascular dysregulation (RVD) on timolol 0.5% alone. Methods: In this prospective, observer-masked, crossover study, 21 ...
Faria-Correia Fernando - - 2013
PURPOSE:To report the tomographic and biomechanical findings before and after treatment of a case of pressure-induced stromal keratopathy (PISK), which was misdiagnosed as diffuse lamellar keratitis (DLK). METHODS:A case report of a referred patient with supposed diagnosis of DLK after LASIK in the right eye. Scheimpflug-based corneal tomography and biomechanical ...
Cougnard-Grégoire Audrey - - 2013
To explore the association of AMD with long-term average blood pressure (BP) parameters, including pulse pressure (PP). The ALIENOR study is a population-based study on age-related eye diseases in 963 residents of Bordeaux, France, aged 73 years or older. AMD was graded from nonmydriatic color retinal photographs, in three exclusive ...
Xu Liang - - 2013
BACKGROUNDWe examined the relationship between arterial hypertension, localized retinal nerve fiber layer defects (RNFLDs), and retinal vascular abnormalities.METHODSThe study included 359 patients with arterial hypertension and 331 individuals without hypertension as control subjects. Localized RNFLDs and retinal vascular abnormalities were assessed on fundus photographs.RESULTSAfter adjusting for blood concentrations of glycosylated ...
Krilis Matthew - - 2013
Amyl nitrite 'poppers' are recreational drugs, which are a potent source of nitric oxide. The use of 'poppers' can cause psychoactive stimulation, reduced blood pressure, tachycardia and involuntary muscle relaxation. Their use is becoming increasingly common around the world, including approximately 60% of Australia's male homosexual community. We report the ...
Lamelas Frank J - - 2013
An asymmetric moissanite anvil cell is used to study aqueous solutions of ammonium iodide at pressures up to 10 kbar. The index of refraction is measured using the rotating Fabry-Perot technique, with an accuracy of approximately 1%. The mass density and molar volume of the solutions are estimated using the ...
Wu Stanley - - 2013
We explored the technological concept of the nanoparticle structuring in the wedge film with regards to its application to the oily soil removal phenomena. The experimental and theoretical investigations on the cleansing of canola oil from a glass substrate using commercially available nanofluids were pursued. Five commercially-available nanofluids with pHs ...
Rabbani Mohammad Gulam - - 2013
Hole-some mixture: A 2D mesoporous covalent organic framework featuring expanded pyrene cores and linked by imine linkages has high surface area (SA(BET) =2723 m(2)  g(-1) ) and exhibits significant gas storage capacities under high pressure, which make this class of material very promising for gas storage applications.
Thurtell Matthew J MJ Department of Ophthalmology & Visual Sciences, University of Iowa, 200 Hawkins Dr PFP, Iowa City, IA, 52242, USA, - - 2013
Idiopathic intracranial hypertension (IIH, pseudotumor cerebri) is a syndrome of elevated intracranial pressure of unknown cause that occurs predominantly in obese women of childbearing age. It is a diagnosis of exclusion and, therefore, other causes of increased intracranial pressure must be sought with history, imaging, and cerebrospinal fluid examination before ...
Taibbi Giovanni G Department of Ophthalmology and Visual Sciences, The University of Texas Medical Branch, Galveston, TX 77555-1106, - - 2013
We report ocular changes occurring in a healthy human subject enrolled in a bed rest (BR) study designed to replicate the effects of a low-gravity environment. A 25-yr-old Caucasian man spent 30 consecutive days in a 6 degrees head-down tilt (HDT) position at the NASA Flight Analogs Research Unit. Comprehensive ...
Murdock Adrian T - - 2013
We report that the shape, orientation, edge geometry and thickness of chemical vapour deposition graphene domains can be controlled by the crystallographic orientations of Cu substrates. Under low-pressure conditions single layer graphene domains align with zig-zag edges parallel to a single <101> direction on Cu(111) and Cu(101), while bilayer domains ...
Murgan Ilina - - 2013
INTRODUCTION Increasing evidence suggests that arterial hypertension (AHT) may begin in childhood and result in the premature development of cardiovascular disease. In view of this, we believed it would be important to investigate the early vascular changes related to early hypertension at the micro- and macrovascular levels both under normal ...
Kong Chang Yi - - 2013
The diffusion coefficients D(12) of phenylbutazone at infinite dilution in supercritical CO(2) were measured by the chromatographic impulse response (CIR) method. The measurements were carried out over the temperature range from 308.2 to 343.2K at pressures up to 40.0MPa. In addition, the D(12) data of phenylbutazone at infinite dilution in ...
Triantafyllou Areti - - 2013
BACKGROUND Hypertensive patients with retinal arteriolar abnormalities are at increased risk for cardiovascular events. However, the extent of retinal microvascular changes in naïve, never-treated patients with hypertension of short duration has not been established. In addition to this, the lack of relevant data about other phenotypes of hypertension (masked and ...
Kotliar Konstantin - - 2013
OBJECTIVE: Hypertension is characterized by microvascular remodeling resulting in increased wall/lumen ratio and elevated microvascular stiffness. Aiming to transform the measurement of macrovascular stiffness into a microvascular environment we introduce a non-invasive method to assess retinal pulse wave velocity (rPWV). rPWV alterations in early hypertension are investigated in detail. The ...
Langendorf S - - 2013
A novel method for the characterization and qualification of Hall effect thruster propellant distributors is presented. A quantitative measurement of the azimuthal number density uniformity, a metric which impacts propellant utilization, is obtained from photographs of a premixed flame anchored on the exit plane of the propellant distributor. The technique ...
Barak Yoreh - - 2013
The purpose of this study was to compare postoperative intraocular pressures and percentage of vitreous cavity gas fill one day following 25-gauge pars plana vitrectomy with 20% versus 25% sulfur hexafluoride (SF6) gas fill. This was a retrospective review of 187 consecutive cases of 25-gauge pars plana vitrectomy with complete ...
Reimann Manja - - 2013
To assess acute effects of bevacizumab (anti-VEGF therapy) on cerebral microvessels and systemic cardiovascular regulation. 20 consecutive patients with colorectal cancer (median age: 60.4 years, range 45.5-73.9 years) received bevacizumab intravenously (5 mg/kg) uncoupled of chemotherapy. Prior to and within the first 24 hours after bevacizumab infusion, patients were investigated for retinal endothelial function. ...
Moreira Grazielle Furtado - - 2013
The objective of this study was to evaluate different strategies for the application of entomopathogenic nematodes (EPN). Three different models of spray nozzles with air induction (AI 11003, TTI 11003 and AD-IA 11004), three spray pressures (207, 413 and 720 kPa), four different additives for tank mixtures (cane molasses, mineral ...
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