Shear stress is a major determinant of endothelial apoptosis, but its role in the in vivo release of shed membrane microparticles by endothelial cells remains unknown. Thus, we sought to evaluate the possible relationship between circulating endothelial microparticle levels and laminar shear stress in end-stage renal disease patients with high cardiovascular risk, whose levels of endothelial mi...

The extensional viscosity is an important rheological characteristic of polymer melts. It is however not as frequently reported on as the shear viscosity. The extensional viscosity is of special interest when considering polymeric materials for foaming and film blowing processes. Here, the extensional (and shear) viscosity along with the melt strength and the tensile properties of the correspon...

There is clear and incontrovertible evidence that the viscosity of many liquids depends on the pressure. While the density, as the pressure is increased by orders of magnitude, suffers small changes in its value, the viscosity changes dramatically. It can increase exponentially with pressure. In many fluids, there is also considerable evidence for the viscosity to depend on the rate of deformat...

OBJECTIVES The atherosclerotic process in arteries is correlated with the local wall shear stress (WSS). Plaque development particularly occurs in regions with recirculation (ie, where the WSS oscillates). We investigated the effects of non-Newtonian blood viscosity, variations in flow rate, and vessel diameter on wall phenomena in a carotid bifurcation model. MATERIALS AND METHODS The flow t...

Blood viscosity is a crucial hemodynamic biomarker because it determines the friction against blood vessels, the quantity of oxygen that is delivered to organs and tissues, and the degree of exertion by the heart. Many factors affect blood viscosity, either directly or inversely. e.g., fibrinogen and hematocrit. The effect of other factors (e.g., cholesterol) on blood viscosity is still under i...

The California Mastitis Test has previously been adapted for use in an inline, cow-side sensor and relies on the fact that the viscosity of the gel formed during the test is proportional to the somatic cell concentration. In this paper, the use of capillary and rotational viscometry was compared in light of the expected rheology of the gel formed during the test. It was found that the gel is no...

BLOOD has anomalous rheological properties, particularly in certain disease states. It may therefore be necessary to consider these properties when attempting to assess and perhaps to improve the state of a patient's cerebral circulation. So what evidence is there that cerebral blood flow (CBF) is affected by viscosity? Before attempting to answer this question, one should be aware of what infl...

Background: The study of rheological properties of blood has special interest since it is a circulating fluid exposed to shear rates during its life time. This work aims to investigate the influence of whole body gamma irradiation on the rheological properties of rat’s blood. The applied shear rate was from 12 to 375 s-1. Low shear viscosity (up to 100 s-1) depends mainly on the erythroc...

The velocity, shear-rate, variable viscosity, and variable power-law index profiles are calculated for non-Newtonian fluids using the finite difference method. The calculations are carried out for an actual viscosity function obtained by a cilrve fit through measured data and for the corresponding power law model, the simplest and most often used form for non­ Newtonian viscosity function appro...

The rheology of bubble-bearing suspensions is investigated through a series of three-dimensional boundary integral calculations in which the effects of bubble deformation, volume fraction, and shear rate are considered. The behaviour of bubbles in viscous flows is characterized by the capillary number, Ca, the ratio of viscous shear stresses that promote deformation to surface tension stresses ...