We develop a three-dimensional nite-deformation cohesive element and a class of irreversible cohesive laws which enable the accurate and e cient tracking of dynamically growing cracks. The cohesive element governs the separation of the crack anks in accordance with an irreversible cohesive law, eventually leading to the formation of free surfaces, and is compatible with a conventional nite elem...

This paper studies the initiation of cohesive cracks in the thermal shock problem through a variational analysis. A two-dimensional semi-infinite slab with an imposed temperature drop on its free surface is considered. Assuming that cracks are periodically distributed and orthogonal to the surface, at short times we show that the optimum is a distribution of infinitely close cohesive cracks. Th...

Cooperation between cadherins and the actin cytoskeleton controls many aspects of epithelial biogenesis. We report here that myosin VI critically regulates the morphogenesis of epithelial cell-cell contacts. As epithelial monolayers mature in culture, discontinuous cell-cell contacts are initially replaced by continuous (cohesive) contacts. Myosin VI is recruited to cell contacts as they become...

OBJECTIVE To study the incidence and distribution of adherent Gardnerella vaginalis. METHODS Bacteria adherent to desquamated epithelial cells in the urine were detected using fluorescence in situ hybridization (FISH). Urine from patients with bacterial vaginosis (BV, n = 20), their partners (n = 10) and different control populations (n = 344) including pregnant women and their partners, rand...

that varies with distance, r, from the crack tip as r 1 2 . In this paper, a traction free plane stress wedge with a discrete cohesive zone along the intended crack-path is studied. Of interest is the in uence of the cohesive zone on the crack tip stress eld. Further, the in uence of the cohesive zone on the strain energy release rate is also investigated. Two example problems are studied; a do...

Project SUMMARY 1 Project DESCRIPTION 3 I. Objectives 3 II. Rationale 3 III. Conceptual Perspective 3 Modeling Strategies, Patterns and Mathematical Theorems, and Working Hypotheses 4 Heuristics for Theorizing Dynamic Evolution of Coherence among Formal Patterns 7 Dynamics 9 IV Measurement: Detecting Patterns in Networks 9 V. Hypothesis Tests on Social Transformations 10 VI. Modeling and Hypoth...

A one-dimensional vertical two-phase flow model for sedimentation-consolidation process is presented. The model is based on solving the continuity and momentum equations for both fluid and solid phases. In the non-cohesive case, the momentum transfer between the two phases is reduced to the drag force around a single particle modified to take the hindrance effects into account. In the cohesive ...