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Grizelj I I Department of Physical Therapy, Department of Medicine, University of Illinois at Chicago, Chicago, IL, 60612; Department of Physiology and Immunology, Faculty of Medicine University of Osijek, Osijek, - - 2014
The hypothesis of this study was that microvascular flow-induced dilation (FID) and acetylcholine-induced dilation (AChID) is impaired in visceral (VAT) compared to subcutaneous adipose tissue (SAT) arterioles in morbidly obese women. Additional aim was to determine the mechanisms contributing to FID and AChID in VAT and SAT arterioles. Arterioles were ...
Toda Noboru - - 2014
Increasing evidence supports the idea that chronic hypoperfusion in the brain is responsible for the pathogenesis underling Alzheimer's disease (AD). Obesity at midlife is associated with the risk of cognitive loss and AD at later life. Obesity decreases cerebral blood flow that is associated with decreased synthesis and actions of ...
Yang Yaling - - 2012
Despite accumulating evidence of structural deficits in individuals with psychopathy, especially in frontal regions, our understanding of systems-level disturbances in cortical networks remains limited. We applied novel graph theory-based methods to assess information flow and connectivity based on cortical thickness measures in 55 individuals with psychopathy and 47 normal controls. ...
Bassingthwaighte James B - - 2012
Given the mono-functional, highly coordinated processes of cardiac excitation and contraction, the observations that regional myocardial blood flows, rMBF, are broadly heterogeneous has provoked much attention, but a clear explanation has not emerged. In isolated and in vivo heart studies the total coronary flow is found to be proportional to ...
Nalluri Venkateshwar Rao - - 2012
Powder flow of mixtures is complex and not properly understood. The selection of drug-excipient blends with inadequate powder flow can lead to quality issues of the final dosage form. Therefore, this work aims at a better understanding of how changes in powder flow of binary blends can lead to weight ...
Virdi Makhan L - - 2012
Groundwater exchanges with lakes resulting from cyclical wet and dry climate extremes maintain lake levels in the environment in ways that are not well understood, in part because they remain difficult to simulate. To better understand the atypical groundwater interactions with lakes caused by climatic extremes, an original conceptual approach ...
Kamioka Hiroshi - - 2012
Osteocytes play a pivotal role in the regulation of skeletal mass. Osteocyte processes are thought to sense the flow of interstitial fluid that is driven through the osteocyte canaliculi by mechanical stimuli placed upon bone, but how this flow elicits a cellular response is virtually unknown. Modern theoretical models assume ...
Vilfan A - - 2012
We describe a multipole expansion for the low-Reynolds-number fluid flows generated by a localized source embedded in a plane with a no-slip boundary condition. It contains 3 independent terms that fall quadratically with the distance and 6 terms that fall with the third power. Within this framework we discuss the ...
Fry Brendan C - - 2012
Recent methods for imaging microvascular structures provide geometrical data on networks containing thousands of segments. Prediction of functional properties, such as solute transport, requires information on blood flow rates also, but experimental measurement of many individual flows is difficult. Here, a method is presented for estimating flow rates in a ...
Fraser Graham M GM Department of Medical Biophysics, University of Western Ontario, London, Ontario, Canada. - - 2012
We describe a systematic approach to modeling blood flow using reconstructed capillary networks and in vivo hemodynamic measurements. Our goal was to produce flow solutions that represent convective O(2) delivery in vivo. Two capillary networks, I and II (84 × 168 × 342 and 70 × 157 × 268 μm(3)), ...
Gallo Diego - - 2012
The main purpose of the study is to verify if helical flow might be a surrogate marker of the exposure to disturbed shear in normal carotid bifurcations. Based on hemodynamic simulations data of 50 carotid bifurcations, we defined appropriate helicity-based bulk flow descriptors and multivariate linear regression analysis was performed ...
Chaudhuri Pinaki - - 2012
Using numerical simulations, we study the gravity driven flow of jammed soft disks in confined channels. We demonstrate that confinement results in increasing the yield threshold for the Poiseuille flow, in contrast to the planar Couette flow. By solving a nonlocal flow model for such systems, we show that this ...
Wu Lei - - 2012
Little research has been conducted to investigate fate and transport of colloids in shallow overland flow through dense vegetation under unfavorable chemical conditions. In this work, the single collector attachment efficiency (α) of colloid capture by a simulated plant stem (i.e. cylindrical collector) in laminar overland flow was measured directly ...
Santhanakrishnan Arvind - - 2012
Quantifying the flows generated by the pulsations of jellyfish bells is crucial for understanding the mechanics and efficiency of their swimming and feeding. Recent experimental and theoretical work has focused on the dynamics of vortices in the wakes of swimming jellyfish with relatively simple oral arms and tentacles. The significance ...
Petersen Timothy W - - 2012
The analysis of marine phytoplankton using flow cytometry has enabled the discovery of new taxa and has contributed new understanding to the dynamics and ecological contributions of phytoplankton to the global carbon cycle. Marine phytoplankton are uniquely suited to analysis by flow cytometry because of their size, pigment content, and ...
Yoshida Naohisa - - 2012
PURPOSE: Colorectal endoscopic submucosal dissection (ESD) has not been standardized due to technical difficulties and requires extensive training for reliability. Ex vivo animal model is convenient, but has no blood flow. The objective of this study is to evaluate the characteristics of various ex vivo animal models including a blood ...
Sauret Alban - - 2012
Control of fluid dynamics at the micrometer scale is essential to emulsion science and materials design, which is ubiquitous in everyday life and is frequently encountered in industrial applications. Most studies on multiphase flow focus on oil-water systems with substantial interfacial tension. Advances in microfluidics have enabled the study of ...
Blanco P J - - 2012
The present work deals with the parameter identification problem in outflow models used in one-dimensional simulations of arterial blood flow. Specifically, the resistive elements that define the models used to account for the blood supply to the vascular territories in arterial networks are computed by solving a system of non-linear ...
Lin Shiang-Chi - - 2012
Flow cytometry is a technique capable of optically characterizing biological particles in a high-throughput manner. In flow cytometry, three dimensional (3D) hydrodynamic focusing is critical for accurate and consistent measurements. Due to the advantages of microfluidic techniques, a number of microfluidic flow cytometers with 3D hydrodynamic focusing have been developed ...
Fasano Antonio - - 2012
Modeling blood coagulation has taken various directions in recent years, depending on the aspects that authors wish to emphasize. In this paper we want to address an issue that has been systematically ignored in the relevant literature, namely the effect of blood slip at the vessels wall. The presence of ...
Lu X Lucas - - 2012
The fluid flow in the lacunar-canalicular system of bone is an essential mechanical stimulation on the osteocyte networks. Due to the complexity of human physical activities, the fluid shear stress on osteocyte bodies and processes consists of both steady and oscillatory components. In this study, we investigated and compared the ...
Bakker Mark - - 2013
Steady interface flow in heterogeneous aquifer systems is simulated with single-density groundwater codes by using transformed values for the hydraulic conductivity and thickness of the aquifers and aquitards. For example, unconfined interface flow may be simulated with a transformed model by setting the base of the aquifer to sea level ...
Xinhui Si - - 2012
In this paper, a simple mathematical model depicting blood flow in the deforming porous channel is developed with an emphasis on the permeability property of the blood vessel and slip boundary based on Beavers and Joseph slip condition. In this study, the blood is represented by a micropolar fluid. With ...
Korn Claudia - - 2012
Blood vessel network formation is a pivotal process of physiologic development as well as pathological conditions such as tumor growth, diabetic retinopathy and cardiovascular diseases(1,2). During neovascularization, vasculogenesis is followed by the well described process of sprouting angiogenesis, including tip cell induction and selection, sprout elongation and stalk formation, leading ...
Thomas A - - 2012
Purpose: A dynamic phantom for quality assurance of dynamic contrast enhanced (DCE) imaging has been designed to achieve perfusion (in terms of flow rates) comparable to capillary exchange that occurs in human tissue. The validation of this physical phantom is critical to establishing its usefulness as a quality assurance tool. ...
Lakghomi B - - 2012
The importance of horizontal flow patterns and bubble aggregation on the ability of dissolved air flotation (DAF) systems to improve bubble removal during drinking water treatment were explored using computational fluid dynamics (CFD) modeling. Both analytical and CFD analyses demonstrated benefits to horizontal flow. Two dimensional CFD modeling of a ...
Espino Daniel M - - 2012
A transient multi-physics model of the mitral heart valve has been developed, which allows simultaneous calculation of fluid flow and structural deformation. A recently developed contact method has been applied to enable simulation of systole (the stage when blood pressure is elevated within the heart to pump blood to the ...
Hoshino Kazunori - - 2012
We describe a computational analysis method to evaluate the efficacy of immunomagnetic rare cell separation from non-Newtonian particulate blood flow. The core procedure proposed here is calculation of local viscosity distributions induced by red blood cell (RBC) sedimentation. Numerical calculation methods have previously been introduced to simulate particulate behavior of ...
Shenton Will - - 2012
There have been significant diversions of water from rivers and streams around the world; natural flow regimes have been perturbed by dams, barriers and excessive extractions. Many aspects of the ecological 'health' of riverine systems have declined due to changes in water flows, which has stimulated the development of thinking ...
Kamrin Ken - - 2012
Extending recent modeling efforts for emulsions, we propose a nonlocal fluidity relation for flowing granular materials, capturing several known finite-size effects observed in steady flow. We express the local Bagnold-type granular flow law in terms of a fluidity ratio and then extend it with a particular Laplacian term that is ...
Bharadwaj Koonal N - - 2012
Hemodynamic forces play an important role in sculpting the embryonic heart and its valves. Alteration of blood flow patterns through the hearts of embryonic animal models lead to malformations that resemble some clinical congenital heart defects, but the precise mechanisms are poorly understood. Quantitative understanding of the local fluid forces ...
Viitala Tapani - - 2012
We have used computational fluid dynamics modeling (CFD) to synchronize the flow conditions in the flow channels of two complementary surface-sensitive characterization techniques: surface plasmon resonance (SPR) and quartz crystal microbalance (QCM). Since the footprint of the flow channels of the two devices is specified by their function, the flow ...
Guibert Romain - - 2012
Vascular domains have been described as being coupled to neuronal functional units enabling dynamic blood supply to the cerebral cyto-architecture. Recent experiments have shown that penetrating arterioles of the grey matter are the building blocks for such units. Nevertheless, vascular territories are still poorly known, as the collection and analysis ...
Pereira Arturo - - 2012
BACKGROUND: The temporal pattern of the biologic mechanism linking red blood cell (RBC) storage duration with clinical outcomes is yet unknown. This study investigates how such a temporal pattern can affect the power of randomized controlled trials (RCT) to detect a relevant clinical outcome mediated by the transfusion of stored ...
Cubaud Thomas - - 2012
The evolution of carbon dioxide bubbles dissolving in water is experimentally examined using long microchannels. We study the coupling between bubble hydrodynamics and dissolution in confined geometries. The gas impregnation process in liquid produces significant flow rearrangements. Depending on the initial volumetric liquid fraction, three operating regimes are identified, namely ...
Li Xuejin - - 2012
The motion of a suspension of red blood cells (RBCs) flowing in a Y-shaped bifurcating microfluidic channel is investigated using a validated low-dimensional RBC model based on dissipative particle dynamics. Specifically, the RBC is represented as a closed torus-like ring of ten colloidal particles, which leads to efficient simulations of ...
Lacina Karel - - 2012
Four-channel flow-through electrochemical cell working in thin-layer regime was designed, fabricated and characterized experimentally and in computational fluid dynamics (CFD) simulations. The new principle of operation allows reproducible splitting of a stream of liquid into multiple flow channels. Systems comprising of 2-, 3-, 4- and 8-channels were tested. The proper ...
Dupont Aurélien - - 2012
The frequent eruptions of Piton de la Fournaise volcano (Reunion island) release an important quantity of magmatic gas into the atmosphere and generates infrasonic airwaves. The series of volcanic noise recorded, in the near field, on a microbarometer between 1992 and 2008 bring new constraints on the functioning of the ...
Dupont Aurélien - - 2012
The frequent eruptions of Piton de la Fournaise volcano (Reunion island) release an important quantity of magmatic gas into the atmosphere and generates infrasonic airwaves. The series of volcanic noise recorded, in the near field, on a microbarometer between 1992 and 2008 bring new constraints on the functioning of the ...
Martorell Jordi J Department of Chemical Engineering, IQS, Universitat Ramon Llull, Barcelona, - - 2012
This paper reviews how biomedical engineers, in collaboration with physicians, biologists, chemists, physicists, and mathematicians, have developed models to explain how the impact of vascular interventions on blood flow predicts subsequent vascular repair. These models have become increasingly sophisticated and precise, propelling us toward optimization of cardiovascular therapeutics in general ...
Jakiela Slawomir - - 2012
Even at moderate values of Reynolds number [e.g., Re=O(1)] a curved interface between liquids can induce an abrupt transition between topologically different configurations of laminar flow. Here we show for the first time direct evidence of a sharp transition in the speed of flow of a droplet upon a small ...
Resto Pedro J - - 2012
We describe and characterize a pumping mechanism that leverages the momentum present in small droplets ejected from a micro-nozzle to drive flow in an open microfluidic device. This approach allows driving flow in a microfluidic device in a regime that offers unique features different to those achievable with typical passive ...
Kang Yang Jun - - 2012
Fluctuations in flow rate invariably occur in microfluidic devices. This fluidic instability results in a deteriorating performance and the suspension of their unique functions occasionally. In this study, a fluidic-LPF (low pass filter), which is composed of an ACU (air compliance unit) and a FCSP (fluidic channel with high fluidic ...
Edwards Bruce S BS Department of Pathology, University of New Mexico, Albuquerque, New Mexico, USA. - - 2012
Flow cytometry specializes in high-content measurements of cells and particles in suspension. Having long excelled in analytical throughput of single cells and particles, only recently with the advent of HyperCyt sampling technology, flow cytometry's multiexperiment throughput has begun to approach the point of practicality for efficiently analyzing hundreds-of-thousands of samples, ...
Sagot P - - 2012
OBJECTIVE: To measure the accuracy of blood transfusion (timing and number of blood units) in postpartum hemorrhage (PPH) in a perinatal network. STUDY DESIGN: (1) The ANONYMAT software system was used for anonymization and linkage of two large stand-alone databases, the Burgundy Perinatal Network (BPN) and the National Blood Centre ...
Li Wentao - - 2012
We designed and fabricated a novel microfluidic device that can be operated through simple finger squeezing. On-chip microfluidic flow control is enabled through an optimized network of check-valves and squeeze-pumps. The sophisticated flow system can be easily constructed by combining a few key elements. We implemented this device to perform ...
Heitmuller Franklin T - - 2012
Instream-flow scientists embrace streamflow as the master variable driving aquatic and riparian ecosystems, and that natural flow variability is imperative for river conservation and restoration efforts. Sediment transport, which is critical for maintenance of physical habitats in rivers and floodplains, has received less direct attention from instream-flow practitioners. This article ...
Huang W - - 2012
Radio-frequency Ablation (RFA) has been used in liver surgery to minimize blood loss during tissue division. However, the current RFA tissue division method lacks an effective way of determining the stoppage of blood flow. There is limitation on the current state-of-the-art Laser Doppler Flow sensor due to its small sensing ...
Kerner Boris S - - 2012
Based on numerical simulations of a stochastic three-phase traffic flow model, we reveal the physics of the fundamental hypothesis of three-phase theory that, in contrast with a fundamental diagram of classical traffic flow theories, postulates the existence of a two-dimensional (2D) region of steady states of synchronized flow where a ...
Siddiqui Ruqaiyyah - - 2012
Transmigration of neuropathogens across the blood-brain barrier is a key step in the development of central nervous system infections, making it a prime target for drug development. The ability of neuropathogens to traverse the blood-brain barrier continues to inspire researchers to understand the specific strategies and molecular mechanisms that allow ...
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