Shear thickening is a widespread phenomenon in suspension flow that, despite sustained study, is still the subject of much debate. The longstanding view that shear thickening is due to hydrodynamic clusters has been challenged by recent theory and simulations suggesting that contact forces dominate, not only in discontinuous, but also in continuous shear thickening. Here, we settle this dispute...

The aim of this thesis was to investigate the effect of pelvic suspension on beef with different background and different genders. The response to pelvic suspension was studied in longissimus, semimembranosus, adductor, gluteus and psoas muscles from young bulls, bulls, heifers and cows. Prolonged ageing time until 14 days was evaluated for longissimus from heifers. It was concluded that pelvic...

We present a systematic numerical investigation of the shear strength and structure of granular packings composed of irregular polyhedral particles. The angularity of the particles is varied by increasing the number of faces from 8 (octahedronlike shape) to 596. We find that the shear strength increases with angularity up to a maximum value and saturates as the particles become more angular (be...

Hemodynamic forces modulate various endothelial cell functions under gene regulation. Previously, we have shown that fibrinolytic activity of endothelial cells is enhanced by the synergistic effects of shear stress and cytokines. In this study, we investigated the effect of shear stress on tumor necrosis factor (TNF)-alpha-induced tissue factor (TF) expression in cultured human umbilical vein e...

Von Willebrand factor (VWF) plays a central role in hemostasis. Triggered by shear-stress, it adheres to platelets at sites of vascular injury. Inactivation of VWF has been associated to the shielding of its adhesion sites and proteolytic cleavage. However, the molecular nature of this shielding and its coupling to cleavage under shear-forces in flowing blood remain unknown. In this study, we d...

Flow-enhanced cell adhesion is an unexplained phenomenon that might result from a transport-dependent increase in on-rates or a force-dependent decrease in off-rates of adhesive bonds. L-selectin requires a threshold shear to support leukocyte rolling on P-selectin glycoprotein ligand-1 (PSGL-1) and other vascular ligands. Low forces decrease L-selectin-PSGL-1 off-rates (catch bonds), whereas h...

[Purpose] The purpose of this study was to investigate the influence of sacral sitting in a wheelchair on contact pressure on the buttocks and back, and shear force on the ischial region. [Subjects and Methods] Twenty-six healthy adults assumed two postures while seated in a wheelchair: a basic sitting posture, and sacral sitting with the pelvis tilted posteriorly and the ischium slid forward b...

This paper discusses a novel dynamic resonant wall shear stress sensor concept based on an oscillating sensor operating near resonance. The interaction between the oscillating sensor surface and the fluid above it is modelled using the unsteady laminar boundary layer equations. The numerical experiment shows that the effect of the oscillating shear stress is well correlated by the Hummer number...

We report on experimentally observed shear stress fluctuations in both granular solid and fluid states, showing that they are non-Gaussian at low shear rates, reflecting the predominance of correlated structures (force chains) in the solidlike phase, which also exhibit finite rigidity to shear. Peaks in the rigidity and the stress distribution's skewness indicate that a change to the force-bear...