Epidemiological and experimental studies suggest that diesel exhaust particles (DEPs) may be associated with increased respiratory mortality and morbidity. Several recent studies have also shown that DEPs increase the production of inflammatory cytokines by human bronchial epithelium (HBE) cells in vitro. The present study investigates the effects of DEPs on the interaction of l-HBE cells (16HB...

Abstract: An elastic stiffness matrix was derived in the case of distortion of a restrained thinwalled I-section beam using the minimum total stationary elastic energy condition (Przemieniecki J S 1968 Theory of Matrix Structural Analysis, McGraw-Hill, NY). The function describing the angle of distortion was adopted form the solution of differential equation in the case of restrained distortion...

Cellular responses to chemical cues are at the core of a myriad of fundamental biological processes ranging from embryonic development to cancer metastasis. Most of these biological processes are also influenced by mechanical cues such as the stiffness of the extracellular matrix. How a biological function is influenced by a synergy between chemical concentration and extracellular matrix stiffn...

The role of a stiffening extra-cellular matrix (ECM) in cancer progression is documented but poorly understood. Here we use a conditioning protocol to test the role of nonmuscle myosin II isoforms in cell mediated ECM arrangement using collagen constructs seeded with breast cancer cells expressing shRNA targeted to either the IIA or IIB heavy chain isoform. While there are several methods avail...

45 46 The myofibroblastic differentiation of hepatic stellate cells (HSC) is a critical event in liver 47 fibrosis and is part of the final common pathway to cirrhosis in chronic liver disease from 48 all causes. The molecular mechanisms driving HSC differentiation are not fully 49 understood. Because macroscopic tissue stiffening is a feature of fibrotic disease, we 50 hypothesized that mechan...

This paper presents a closed-form formulation and geometrical interpretation of the derivatives of the Jacobian matrix of fully parallel robots with respect to the moving platforms’ position/orientation variables. Similar to the Jacobian matrix, these derivatives are proven to be also groups of lines that together with the lines of the instantaneous direct kinematics matrix govern the singulari...

The importance of surface tension effects is being recognized in the context of soft composite solids, where they are found to significantly affect the mechanical properties, such as the elastic response to an external stress. It has recently been discovered that Eshelby's inclusion theory breaks down when the inclusion size approaches the elastocapillary length L≡γ/E, where γ is the inclusion/...

Scleroderma is a multisystem fibroproliferative disease with no effective medical treatment. Myofibroblasts are critical to the fibrogenic tissue repair process in the skin and many internal organs. Emerging data support a role for both matrix stiffness, and transforming growth factor β1 (TGFβ1), in myofibroblast differentiation. Transient receptor potential vanilloid 4 (TRPV4) is a mechanosens...

RATIONALE Although an age-related decrease in NO bioavailability contributes to vascular stiffness, the underlying molecular mechanisms remain incompletely understood. We hypothesize that NO constrains the activity of the matrix crosslinking enzyme tissue transglutaminase (TG2) via S-nitrosylation in young vessels, a process that is reversed in aging. OBJECTIVE We sought to determine whether ...

We consider an algebraic derivation of multilevel preconditioners which are based on a sequence of finite element stiffness matrices. They correspond to a sequence of triangulations obtained by successive refinement and the associated finite element discretizations of second-order selfadjoint elliptic boundary value problems. The stiffness matrix at a given discretization level is partitioned i...