The effect of non-uniform heat generation on an unsteady MHD laminar boundary layer flow of viscous, incompressible fluid over a vertical stretching plate embedded in a sparsely packed porous medium is investigated numerically. The flow in the porous medium is governed by Brinkman-Forchheimer extended Darcy model. The variation of porosity, permeability and thermal conductivity is assumed. By a...

PURPOSE To examine the effects of interleukin (IL)-1beta on the resistance and permeability of the tight junctions of cultured retinal pigment epithelial cells. METHODS A human RPE cell line (ARPE-19) cultured on microporous filter-supports was used. IL-1beta and monoclonal anti-IL-1beta antibody-treated IL-1beta (mAbIL-1beta) were added to the standard culture medium. Transepithelial resista...

Z. Naturforsch. 54 a, 411-416 (1999); received April 19, 1999 The effects of collisions with neutral atoms on the hydromagnetic stability of the plane interface separating two streaming superposed composite plasmas of uniform densities in a porous medium are investigated. In the absence of fluid velocities, it is found, for a potentially stable configuration, that the system remains stable, whi...

An increased intestinal permeability is associated with several diseases. Previously, we have shown that dietary Ca decreases colonic permeability in rats. This might be explained by a calcium-phosphate-induced increase in luminal buffering capacity, which protects against an acidic pH due to microbial fermentation. Therefore, we investigated whether dietary phosphate is a co-player in the effe...

Studies were carried out on the isolated urinary bladder of the toad, Bufo marinus, in order to explain the dependence of active sodium transport on the presence of potassium, in the serosal medium. Attempts to obtain evidence for coupled sodium-potassium transport by the serosal pump were unsuccessful; no relation between sodium transport and uptake of K(42) from the serosal medium was demonst...

Direct investigation of cell permeability has been necessarily limited in its material, since most of the cells of multicellular organisms have not been available for even roughly quantitative study during their life. Hence it is that most of our knowledge of the permeability of cell surfaces has been derived from experiments with plant cells, the eggs of certain invertebrates, and erythrocytes...

Human intestinal Caco-2 cells were differentiated using serum-reduced medium with fetal bovine serum (FBS) added only to the basolateral (BL) medium, and four serum-free media, containing insulin, transferrin, selenium (ITS), or MITO+™ serum extender (ITS plus growth factors), with or without addition of a lipid mixture, respectively. Differentiation was assessed by monitoring monolayer permeab...

We present a generally symmetrical circuit model to describe all kinds of metamaterials with effective permittivity and permeability. The model is composed of periodic structures whose unit cell is a general T-type circuit. Using the effective medium theory, we derive analytical formulations for the effective permittivity and effective permeability of the circuit model, which are quite differen...

While it is true that fly ash contains trace amounts of certain elements, which can be toxic in larger concentrations, it is unlikely that fly ash as used in concrete would exhibit leaching characteristics. First, the permeability of concrete containing fly ash is negligible compared to the permeability of fly ash as typically disposed. This reduced permeability prevents water or other liquids ...