We study the dynamics of the Taylor-Couette flow of shear banding wormlike micelles. We focus on the high shear rate branch of the flow curve and show that for sufficiently high Weissenberg numbers, this branch becomes unstable. This instability is strongly subcritical and is associated with a shear stress jump. We find that this increase of the flow resistance is related to the nucleation of t...

Skeletal muscle arterioles dilate in response to increases in flow velocity/wall shear stress (WSS). The effect of flow/WSS on the diameter of skeletal muscle venules and the possible endothelial mediation of the response, however, have not yet been characterized. Thus changes in diameter of pressurized (10 mmHg) and norepinephrine-preconstricted venules (179 ± 8 μm in diameter) to increases in...

Flow-mediated dilation is aimed at normalization of local wall shear stress under varying blood flow conditions. Blood flow velocity and vessel diameter are continuous and opposing influences that modulate wall shear stress. We derived an index FMDv to quantify wall shear stress normalization performance by flow-mediated dilation in the brachial artery. In 22 fasting presumed healthy men, we fi...

Analyzing piles subjected to lateral loads significantly depends on soil resistance at any point along the pile as a function of pile deflection, known as p-y curve. On the other hand, the deformation characteristics of soil defined as “the soil strain at 50% of maximum deviatoric stress (ε50)” has considerable effect on the generated p-y curve. In this research, several models are proposed to ...

Metallic glasses are known to have a remarkably robust yield strength, admitting Weibull moduli as high for crystalline engineering alloys. However, their postyielding behavior is strongly varying, with large scatter in both flow stress levels and strains at failure. Using x-ray tomography, we reveal how strain-dependent internal evolution of shear-band cavities underlies this unpredictable res...

In this study, two-dimensional finite element modeling was used to study the simultaneous effect of the cell shape and regular cell distribution on the anisotropy of the elastic properties of 316L stainless steel foam. In this way, the uniaxial compressive stress-strain curve was predicted using a geometric model and fully solid 316L stainless steel. The results showed that the elastic tangent ...

Fluid shear stress alters the morphology and function of the endothelium by activating several kinases. Furthermore, shear stress potently inhibits apoptosis of endothelial cells. Since activation of Akt kinase has been shown to prevent cell death, we investigated the effects of shear stress on Akt phosphorylation. To test the hypothesis that shear stress interacts with the Akt kinase pathway, ...

Yield stress materials flow if a sufficiently large shear stress is applied. Although such materials are ubiquitous and relevant for industry, there is no accepted microscopic description of how they yield, even in the simplest situations in which temperature is negligible and in which flow inhomogeneities such as shear bands or fractures are absent. Here we propose a scaling description of the...

Using Brownian Dynamics (BD) simulations we investigate non-equilibrium transitions of sheared colloidal films under controlled shear stress σxz. In our approach the shear rate [small gamma, Greek, dot above] is a dynamical variable, which relaxes on a time scale τc such that the instantaneous, configuration-dependent stress σxz(t) approaches a pre-imposed value. Investigating the dynamics unde...

BACKGROUND Atherosclerotic lesions are predominantly observed in curved arteries and near side branches, where low or oscillatory shear stress patterns occur, suggesting a causal connection. However, the effect of shear stress on plaque vulnerability is unknown because the lack of an appropriate in vivo model precludes cause-effect studies. METHODS AND RESULTS We developed a perivascular shea...