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Calkoen Emmeline E EE Division of Paediatric Cardiology, Department of Paediatrics, Leiden University Medical Center, Leiden, The Netherlands; Department of Anatomy and Embryology, Leiden University Medical Center, Leiden, The - - 2014
To evaluate trans-left atrioventricular valve (LAVV) blood flow and optimize left ventricular inflow quantification in healthy controls and patients after atrioventricular septal defect (AVSD) correction. Twenty-five patients after AVSD correction and 25 controls underwent 4DFlow MRI. Using streamline visualization in four- and two-chamber views, inflow direction at early and late ...
Pedrigi Ryan M RM From the Department of Bioengineering, Imperial College London, London, United Kingdom (R.M.P., S.M.B., V.M., R.K.); NHLI, Imperial College London and NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, United Kingdom (R.d.S.); and MRC-Clinical Sciences Centre, Imperial College London, London, United Kingdom - - 2014
In this review, we summarized the effect of mechanical factors (shear and wall stress) on thin-cap fibroatheroma formation and rupture. To make this review understandable for a biology-oriented audience, we start with detailed definitions of relevant mechanical metrics. We then describe how biomechanics has supported histopathologic efforts to understand the ...
Gülan Utku U Institute of Environmental Engineering, ETH Zurich, Zurich, Switzerland. Electronic address: - - 2014
Cardiovascular diseases can lead to abnormal blood flows, some of which are linked to hemolysis and thrombus formation. Abnormal turbulent flows of blood in the vessels with stenosis create strong shear stresses on blood elements and may cause blood cell destruction or platelet activation. We implemented a Lagrangian (following the ...
Vavic Nataša N Department of Blood Collection, Blood Transfusion Institute, Sv.Save 39, Belgrade, - - 2014
The vasovagal reaction has been widely studied but its anatomic and physiological nature remains uncertain. The mechanisms underlying vasovagal reaction related to blood donation are not completely understood either. Does its occurrence depend on the blood donors' physical characteristics and health variables or psychological factors? On the basis that a ...
Kang Yu-Jung YJ Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 39 Hallymdaehak-gil, Chuncheon, 200-702, Gangwon-do, South - - 2014
The blood glucose profiles were characterized after mice were forced into immobilization stress with various exposure durations. The blood glucose level was significantly enhanced by immobilization stress for 30 min or 1 h, respectively. On the other hand, the blood glucose level was not affected in the groups which were forced into ...
van der Poel Erwin P EP Department of Physics, Mesa+ Institute, and J. M. Burgers Centre for Fluid Dynamics, University of Twente, 7500 AE Enschede, The - - 2014
The effect of various velocity boundary condition is studied in two-dimensional Rayleigh-Bénard convection. Combinations of no-slip, stress-free, and periodic boundary conditions are used on both the sidewalls and the horizontal plates. For the studied Rayleigh numbers Ra between 10^{8} and 10^{11} the heat transport is lower for Γ=0.33 than for ...
Ruef Peter P Department of Pediatrics, Clinic of Neonatology, University of Heidelberg, Germany. - - 2014
The LS300 viscometer permits automated measurements of viscosity at several shear rates of non-Newtonian fluids. We determined whole blood and plasma viscosity, aggregation, red blood cell deformability, and hematocrit of 66 healthy adults. The effects of the anticoagulants EDTA, heparin and citrate, and of centrifugation on blood viscosity (n = ...
Teilmann A Charlotte AC Department of Experimental Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark - - 2014
Facial vein (cheek blood) and caudal vein (tail blood) phlebotomy are two commonly used techniques for obtaining blood samples from laboratory mice, while automated blood sampling through a permanent catheter is a relatively new technique in mice. The present study compared physiological parameters, glucocorticoid dynamics as well as the behavior ...
Dokmanović M M Department for Food Hygiene Technology, Faculty of Veterinary Medicine, University of Belgrade, Bulevar Oslobodjenja 18, 11000 Belgrade, Serbia. Electronic address: - - 2014
Lairage time (short - 8min to 2.7h, n=28 vs. long - 14 to 21.5h, n=72) and pig handling (gentle - no use of stick or electric prod, pig not slipping, falling, nor emitting high-pitched vocalizations vs. rough - where any of these occurred) effects on pig stress and meat quality ...
O'Loughlin Aran A Animal and Bioscience Research Department, Animal & Grassland Research and Innovation Centre, Teagasc, Grange, Dunsany, Co. Meath, Ireland; Department of Biology, National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Co. Kildare, - - 2014
The study objective was to investigate the physiological effects of weaning on beef calves and identify a panel of blood-based welfare biomarkers. On the day (d) of weaning (d 0), 16 spring-born, single-suckled, beef bull calves that previously grazed with their dams at pasture, were assigned to one of two ...
Nechyporchuk Oleksandr O Univ. Grenoble Alpes, LRP, F-38000 Grenoble, France; CNRS, LRP, F-38000 Grenoble, France; Univ. Grenoble Alpes, LGP2, F-38000 Grenoble, France; CNRS, LGP2, F-38000 Grenoble, France; Agefpi. Electronic address: - - 2014
The rheological properties of enzymatically hydrolyzed and TEMPO-oxidized microfibrillated/nanofibrillated cellulose (MFC/NFC) aqueous suspensions were investigated in oscillation and steady-flow modes and were compared with the morphology of the studied materials. The flow instabilities, which introduce an error in the rheological measurements, were discovered during flow measurements. A wall-slip (interfacial slippage ...
Crowe Jennfier J Regional Institute for Studies on Toxic Substances (IRET), Universidad Nacional, Heredia, Costa RicaUmea University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Public Health Sciences, Umea, - - 2014
Sugarcane harvesters in Costa Rica are exposed to heat stress, a likely major risk factor in the Mesoamerican nephropathy epidemic. Routine urinalyses provide important information about kidney function, but have not been reported in detail for this population. Sugarcane cutters (n = 48) provided six spot urine samples, pre- and ...
Boehning Fiete F Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, RWTH Aachen University, Aachen, - - 2014
Reducing hemolysis has been one of the major goals of rotary blood pump development and in the investigational phase, the capability of hemolysis estimation for areas of elevated shear stresses is valuable. The degree of hemolysis is determined by the amplitude of shear stress and the exposure time, but to ...
De Geer Jakob J Faculty of Health Sciences, Department of Medical and Health Sciences, Department of Radiology in Linköping, Center for Medical Image Science and Visualization (CMIV), Linköping University, County Council of Östergötland, Linköping, - - 2014
Dynamic cardiac CT perfusion (CTP) is based on repeated imaging during the first-pass contrast agent inflow. It is a relatively new method that still needs validation. To evaluate the variation in adenosine stress dynamic CTP blood flow as compared to (99m) Tc SPECT. Secondarily, to compare manual and automatic segmentation. ...
Galie Peter A PA Departments of Bioengineering,Physiology, - - 2014
The density and architecture of capillary beds that form within a tissue depend on many factors, including local metabolic demand and blood flow. Here, using microfluidic control of local fluid mechanics, we show the existence of a previously unappreciated flow-induced shear stress threshold that triggers angiogenic sprouting. Both intraluminal shear ...
Gibson Laura A LA School of Environmental Studies, Queen's University, Kingston, ON, K7L 3N6, - - 2014
Mercury (Hg) is a widespread contaminant that has been shown to induce a wide range of adverse health effects in birds including reproductive, physiological and neurological impairments. Here we explored the relationship between blood total Hg concentrations ([THg]) and oxidative stress gene induction in the aquatic piscivorous Double-crested Cormorants (Phalacrocorax ...
Bejaei M M Avian Research Centre, The University of British Columbia, Vancouver, British Columbia, Canada, V6T - - 2014
Ostrich (Struthio camelus) production is a relatively young industry and there has been little research on ostrich welfare during pretransport handling and the transportation process. A heavy body with a high center of gravity makes ostriches' handling and transportation problems different from other livestock. The main objective of this study ...
Taylor Joshua - - 2014
Thrombosis and thromboembolization remain large obstacles in the design of cardiovascular devices. The separated flows that can occur within their geometries are strong contributors to thrombus formation. In this study, thrombus growth within a backward-facing step (BFS) model is investigated, as this geometry can mimic the flow separation found in ...
Heo Kyung-Sun KS Aab Cardiovascular Research Institute, University of Rochester, Rochester, NY 14642, - - 2014
Hemodynamic shear stress, the frictional force acting on vascular endothelial cells, is crucial for endothelial homeostasis under normal physiological conditions. When discussing blood flow effects on various forms of endothelial (dys)function, one considers two flow patterns: steady laminar flow and disturbed flow because endothelial cells respond differently to these flow ...
Cho Young I YI Department of Mechanical Eng. and Mechanics, Drexel University, 3141 Chestnut Street, Philadelphia, PA, 19104, USA, - - 2014
This review examines the emerging role of endothelial shear stress (ESS) and blood viscosity on the initiation and progression of atherosclerosis in peripheral arterial disease. Among the variables determining ESS, blood viscosity has to date been the most overlooked by clinical researchers. Blood viscosity is a laboratory assessment that is ...
Dandekar Vineet K - - 2014
Despite increasing clinical use, there is limited data regarding regadenoson in stress perfusion cardiovascular magnetic resonance (CMR). In particular, given its long half-life the optimal stress protocol remains unclear. Although Myocardial Perfusion Reserve (MPR) may provide additive prognostic information, current techniques for its measurement are cumbersome and challenging for routine ...
Ryotokuji Kenji K Faculty of Health Sciences, Ryotokuji University, Urayasu, - - 2014
We have developed a Stress-free Therapy(®) device wherein "Pinpoint Plantar Long-wavelength Infrared Light Irradiation (PP-LILI)" increases peripheral-deep body temperature and blood flow volume and stabilizes blood pressure as well as significantly reduces stress hormones such as adrenocorticotrophic hormone and cortisol without using drugs. Moreover, we have found this therapy to ...
Yan Z Z University of Wisconsin-Madison, Madison, Wisconsin 53706, - - 2014
Comprehensive 2D turbulence and eddy flow velocity measurements on DIII-D demonstrate a rapidly increasing turbulence-driven shear flow that develops ∼100  μs prior to the low-confinement (L mode) to high-confinement (H mode) transition and appears to trigger it. These changes are localized to a narrow layer 1-2 cm inside the magnetic boundary. Increasing ...
Ghose Somdeb S The Institute of Mathematical Sciences, CIT Campus, Chennai 600113, - - 2014
Recent experiments imaging fluid flow around swimming microorganisms have revealed complex time-dependent velocity fields that differ qualitatively from the stresslet flow commonly employed in theoretical descriptions of active matter. Here we obtain the most general flow around a finite sized active particle by expanding the surface stress in irreducible Cartesian ...
Yen Jen-Hong JH Department of Water Resources and Environmental Engineering, Tamkang University, 151 Ying-Chuan Road, Tamsui, New Taipei, 251, Taiwan, - - 2014
Non-physiologic turbulent flow occurs in medical cardiovascular devices resulting in hemodynamic stresses that may damage red blood cells (RBC) and cause hemolysis. Hemolysis was previously thought to result from Reynolds shear stress (RSS) in turbulent flows. A more recent hypothesis suggests that turbulent viscous shear stresses (TVSS) at spatial scales ...
Evans David J DJ Department of Thoracic Medicine, Hemel Hempstead Hospital, Hemel Hempstead, - - 2014
Previous studies have highlighted flow shear stress as a possible damage mechanism for small airways, in particular those liable to constriction through disease or injury due to mechanical ventilation. Flow experiments in vitro have implicated shear stress as a relevant factor for mechanotransduction pathways with respect to airway epithelial cell ...
Blagojević Milan - - 2014
Practical difficulties, particularly long model development time, have limited the types and applicability of computational fluid dynamics simulations in numerical modeling of blood flow in serial manner. In these simulations, the most revealing flow parameters are the endothelial shear stress distribution and oscillatory shear index. The aim of this study ...
Moh Jeong-Hah JH Division of Mechanical and Automotive Engineering, Wonkwang University, Jeollabuk-do, South - - 2014
The present research investigated the role of blood viscosity on flow within a microvascular network to identify the conditions of blood flow stagnation. When the yield stress of blood was less than 0.005 Pa, there were no stagnant regions in the microvasculature. However, when the yield stress increased to 0.05 ...
Teległów Aneta A Department of Clinical Rehabilitation, University School of Physical Education, Cracow, - - 2014
The aim of this study was to analyze the changes in blood rheology resulting from regular winter swimming. The study was carried out on 12 male winter swimmers. Venous blood for morphological, biochemical and rheological analysis was sampled twice from each winter swimmer - at the beginning of the season ...
Watanabe-Asaka Tomomi - - 2014
The development of blood flow in the heart is crucial for heart function and embryonic survival. Recent studies have revealed the importance of the extracellular matrix and the mechanical stress applied to the valve cushion that controls blood flow to the formation of the cardiac valve during embryogenesis. However, the ...
Kynkäänniemi Sanna-Mari SM Department of Biology, University of Oulu, P.O. Box 3000, FI-90014, Oulu, Finland, - - 2014
Blood-sucking ectoparasites have often a strong impact on the behaviour of their hosts. The annual insect harassment of reindeer (Rangifer tarandus tarandus) has increased in the southern part of the Finnish reindeer herding area because of the recent invasion of a blood-feeding ectoparasitic louse-fly, the deer ked (Lipoptena cervi). We ...
de Zambotti Massimiliano M Center for Health Sciences, SRI International, Menlo Park, CA, USA; Department of General Psychology, University of Padua, Padua, - - 2014
Narcolepsy with cataplexy is a complex sleep disorder that affects the modulation of emotions: cataplexy, the key symptom of narcolepsy, is indeed strongly linked with emotions that usually trigger the episodes. Our study aimed to investigate haemodynamic and behavioural responses during emotional stimulation in narco-cataplexy. Twelve adult drug-naive narcoleptic patients ...
- - 2014
Background: Experimental data suggest stress-related cognitive dysfunction may be associated with increased blood-brain-barrier (BBB) permeability secondary to immune activation. Methods: We investigated the relationship between prolonged and intense physical and psychological combat-training stress, immune activation and blood-brain-barrier permeability in 37 healthy male army medical rapid response troops. Results: Soldiers during ...
Freund Jonathan B JB Mechanical Science & Engineering and Aerospace Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801. Electronic address: - - 2014
It is well known that mechanotransduction of hemodynamic forces mediates cellular processes, particularly those that lead to vascular development and maintenance. Both the strength and space-time character of these forces have been shown to affect remodeling and morphogenesis. However, the role of blood cells in the process remains unclear. We ...
Mostafa T T Department of Andrology and Sexology, Faculty of Medicine, Cairo University, Cairo, - - 2014
This study aimed to assess glutathione-S-transferase (GST) enzyme- oxidative stress (OS) relationship in the internal spermatic vein (ISV) of infertile men associated with varicocele (Vx). Ninety five infertile oligoasthenoteratozoospemic (OAT) men associated with Vx were subjected to history taking, clinical examination and semen analysis. During inguinal varicocelectomy, GST, malondialdehyde (MDA) ...
Hoseinabadi Sedigheh S a Department of Occupational Health , Shahrood University of Medical Sciences , Shahrood , - - 2014
Abstract This study has been carried out to investigate the effect of traffic load on the level of blood adrenaline hormone and its influences on the distance estimation and recognition accuracy among urban bus drivers. The level of blood adrenaline hormone has been regarded as stress index. 69 urban bus ...
Zhang Xiaoyan X From the Department of Biomedical Engineering, University of Kentucky, Lexington (X.Z., R.C., D.R., G.Y., H.Y.S); Math, Science, and Technology Center, Paul L. Dunbar High School, Lexington, KY (D.R.); Division of Cardiovascular Disease, University of Alabama at Birmingham (P.S.); and Saha Cardiovascular Research Center, University of Kentucky, Lexington - - 2014
Shear stress-induced pseudopod retraction is an anti-inflammatory measure that minimizes neutrophil activity and is regulated by membrane cholesterol. We tested the hypothesis that a hypercholesterolemic impairment of shear mechanotransduction alters the neutrophil flow behavior leading to microvascular dysfunction. We examined the shear effects on the flow behavior of human leukocytes. ...
Georgakarakos Efstratios E 1 Department of Vascular Surgery, Democritus Medical School, University Hospital of Alexandroupolis, Alexandroupolis - - - 2014
Purpose: To evaluate the flow phenomena within an aortic endograft with crossed-limbs, comparing to an endograft with the ordinary limb bifurcation.Methods: An endograft model with crossed-limbs was computationally reconstructed based on Computed Tomography patient-specific data, using commercially available software. Accordingly, its analogue model was reconstructed in the ordinary fashion (ordinary ...
Wortel Geert H GH Kamerlingh Onnes Lab, Universiteit Leiden, Postbus 9504, 2300 RA Leiden, The - - 2014
We probe the rheology of weakly vibrated granular flows as function of flow rate, vibration strength, and pressure by performing experiments in a vertically vibrated split-bottom shear cell. For slow flows, we establish the existence of a vibration-dominated granular flow regime, where the driving stresses smoothly vanish as the driving ...
Galay Remil Linggatong RL Department of Pathological and Preventive Veterinary Science, The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida, Yamaguchi, Japan; Laboratory of Emerging Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Korimoto, Kagoshima, - - 2014
Ticks are obligate hematophagous parasites that have successfully developed counteractive means against their hosts' immune and hemostatic mechanisms, but their ability to cope with potentially toxic molecules in the blood remains unclear. Iron is important in various physiological processes but can be toxic to living cells when in excess. We ...
Jodko Daniel D Łódź University of Technology, Institute of Turbomachinery, Łódź, - - 2014
The Ciminio-Brescia arterio-venous fistula is a preferred vascular access for haemodialysis, but it is often associated with the development of vascular complications, due to changes in hemodynamic conditions. Computational fluid dynamics methods were involved to carry out seven simulations of the blood flow through the fistula for the patient specific ...
Vitiello Damien D Research Center, Montreal Heart Institute, Université de Montréal, 5000 Belanger Street East, Montreal, QC, Canada H1T 1C8 ; Departments of Medicine and Pharmacology, Faculty of Medicine, Université de Montréal, Montreal, QC, - - 2014
Background. Changes in cardiopulmonary reserve and biomarkers related to wall stress, inflammation, and oxidative stress concomitantly with the evaluation of peripheral arterial blood flow have not been investigated in patients with heart failure with preserved ejection fraction (HFpEF) compared with healthy subjects (CTL). Methods and Results. Eighteen HFpEF patients and ...
Srivastava Neetu N Department of Mathematics, Amrita Vishwa Vidyapeetham (University), Karnataka 560 035, - - 2014
Analytical investigation of MHD blood flow in a porous inclined stenotic artery under the influence of the inclined magnetic field has been done. Blood is considered as an electrically conducting Newtonian fluid. The physics of the problem is described by the usual MHD equations along with appropriate boundary conditions. The ...
Lim Yuen Feung YF Institute of Food, Nutrition and Human Health, Massey University, Palmerston North, New - - 2014
We investigated the passive mechanical properties of villi in ex vivo preparations of sections of the wall of the distal ileum from the brushtail possum (Trichosurus vulpecula) by using a flow cell to impose physiological and supra-physiological levels of shear stress on the tips of villi. We directly determined the ...
Waltz Xavier X UMR Inserm 1134, Pointe-à-Pitre, F-97159 Guadeloupe, Université des Antilles et de la Guyane, Pointe-à-Pitre, France; Laboratoire ACTES (EA 3596), Département de Physiologie, Université des Antilles et de la Guyane, Pointe-à-Pitre, Guadeloupe, France; Laboratory of Excellence GR-Ex, PRES Sorbonne Paris Cité, Paris, - - 2014
Heat stress is one of the major limiting factors of production efficiency in the swine industry. The aims of the present study were 1) to observe if hemorheological and hematological parameters could be associated to physiological acclimation during the first days of heat stress exposure and 2) to determine if ...
Soulis Jv J Deparment of Civil Engineering, Fluid Mechanics Division, School of Engineering, Demokrition University of Thrace, Xanthi, - - 2014
It is known that blood flow properties such as low/ oscillatory wall shear stress (WSS), high blood viscosity, low blood velocity and high concentration of low density lipoprotein (LDL) macromolecules, are some of the main flow parameters causing atherosclerosis. Limited research has been undertaken on the pulsatile WSS and WSS ...
Talati Pratik P Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37235, USA ; Department of Psychiatry, Vanderbilt University, Nashville, TN 37235, - - 2014
Hippocampal hyperactivity has been proposed as a biomarker in schizophrenia. However, there is a debate whether the CA1 or the CA2/3 subfield is selectively affected. We studied 15 schizophrenia patients and 15 matched healthy control subjects with 3T steady state, gadolinium-enhanced, absolute cerebral blood volume (CBV) maps, perpendicular to the ...
Smith Marissa N - - 2013
To fully understand the potentially harmful effects of prenatal stress exposure impacts, it is necessary to quantify long-term and episodic stress exposure during pregnancy. There is a strong body of research relating psychological stress to elevated cortisol levels in biomarkers. Recently, maternal hair has been used to measure cortisol levels, ...
Bouzid Mehdi M Physique et Mécanique des Milieux Hétérogènes, PMMH UMR 7636 ESPCI-CNRS, Université Paris-Diderot, Université Pierre et Marie Curie, 10 rue Vauquelin, 75005 Paris, - - 2013
The rheology of dense granular flows is studied numerically in a shear cell controlled at constant pressure and shear stress, confined between two granular shear flows. We show that a liquid state can be achieved even far below the yield stress, whose flow can be described with the same rheology ...
Mazzaro Lisa M - - 2013
Handling, including blood collection, has often been discouraged in molting penguins because it is considered an additional stress imposed on birds already experiencing major physiologic stress associated with molting. To evaluate the degree of physiologic stress posed by molting, we compared the hematologic and plasma biochemical values and hormone levels ...
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