Inspired by a question of Lovász, we introduce a hierarchy of nested semidefinite relaxations of the convex hull of real solutions to an arbitrary polynomial ideal, called theta bodies of the ideal. For the stable set problem in a graph, the first theta body in this hierarchy is exactly Lovász’s theta body of the graph. We prove that theta bodies are, up to closure, a version of Lasserre’s rela...

This work deals with the development of a mechanics-based shear model for reinforced concrete (RC) elements strengthened in shear with fiber-reinforced polymer (FRP) and a design/assessment procedure capable of predicting the failure sequence of resisting elements: the yielding of existing transverse steel ties and the debonding of FRP sheets/strips, while checking the corresponding compressive...

We examined the hypothesis that disturbance of laminar flow promotes the attachment of leukocytes to the vessel wall in regions where the wall shear stress is otherwise too high. Isolated neutrophils, lymphocytes, or monocytes were perfused through chambers with backward-facing steps so that vortices occurred with well-defined reattachment of flow. Wall shear stresses downstream in reestablishe...

The material behavior of ligament is determined by its constituents, their organization and their interaction with each other. To elucidate the origins of the multiaxial material behavior of ligaments, we investigated ligament response to shear loading under both quasi-static and rate-dependent loading conditions. Stress relaxation tests demonstrated that the tissue was highly viscoelastic in s...

BACKGROUND Shear-induced platelet aggregation (SIPA) is an important mechanism in thrombogenesis. von Willebrand factor (vWF) binding to platelet glycoprotein Ib (GP Ib) has been found to be crucial for platelet aggregation under the high shear force probably generated in stenosed coronary artery. The physiological significance of vWF-dependent SIPA has not been clarified. METHODS AND RESULTS...

This paper describes the results of an extensive study on the seismic behavior of a structure with damper and without damper under different earthquake acceleration frequency like Earthquake Altadena, Earthquake Lucerne and Earthquake New Hall. It is observed through nonlinear time history analysis that maximum displacement, maximum base shear and maximum acceleration can be effectively reduced...