In sediment mechanics, the conditions for onset of movement are particular importance. However, despite decades research, questions remain unanswered. Thus, physical logic suggests that sediments move more easily on beds inclined in direction flow than horizontal and transport rates correspondingly increased. numerous studies have shown require increased rather decreased shear stress to sloping...

Obstruction of critical blood vessels due to thrombosis or embolism is a leading cause of death worldwide. Here, we describe a biomimetic strategy that uses high shear stress caused by vascular narrowing as a targeting mechanism--in the same way platelets do--to deliver drugs to obstructed blood vessels. Microscale aggregates of nanoparticles were fabricated to break up into nanoscale component...

Abstract. First rheological investigation results of weakly wet granular media are presented. The materials have been examined experimentally and numerically in welldefined shear configurations in steady state, in the intermediate flow regime. For the experiments, a Searl-type ring shear cell with rotating inner cylinder and fixed outer cylinder is used. In the numerical particle simulation app...

Endothelial cells (ECs) that line the inner surface of blood vessels are continuously exposed to fluid frictional force (shear stress) induced by blood flow, and shear stress affects the intracellular calcium ([Ca2+]i), which initiates cellular responses. Here, we studied the effect of long-term exposure of shear stress on [Ca2+]i responses in cultured ECs by using a confocal laser microscope a...

The temporal variability in currents, temperature, and particulate matter concentration were measured in the Mississippi Canyon axis where the thalweg was 300m deep from May–July and August–November 1998 using current meters, thermographs, a light-scattering sensor, and sediment traps. Canyon sediments were sampled by coring and observed using an ROV video camera. Currents in the upper Mississi...

It is well known that fluid mechanical forces directly impact endothelial signaling pathways. But while this general observation is clear, less apparent are the underlying mechanisms that initiate these critical signaling processes. This is because fluid mechanical forces can offer a direct mechanical input to possible mechanotransducers as well as alter critical mass transport characteristics ...

The endothelial glycocalyx, a glycosaminoglycan layer located on the apical surface of vascular endothelial cells, has been shown to be important for several endothelial functions. Previous studies have documented that the glycocalyx is highly abundant in the mouse common carotid region, where the endothelium is exposed to laminar shear stress, and it is resistant to atherosclerosis. In contras...

This paper describes the effects of the elastic modulus and sliding velocity on the friction and shear fracture of smooth silanized rigid disks rotating against thin confined films of poly(dimethylsiloxane) (PDMS) elastomers. A rigid glass disk is rotated against thin PDMS films of different thicknesses and moduli bonded to a glass plate at various speeds. While the disk rotates on the PDMS coa...

A simple Rouse-type model, generalized to incorporate the effects of chemical cross-links, is used to obtain a theoretical prediction for the critical behavior of the normal-stress coefficients Psi(1) and Psi(2) in polymeric liquids when approaching the gelation transition from the sol side. While the exact calculation shows Psi(2) identical with 0, a typical result for these types of models, a...