polyacrylonitrile (pan) membranes with nano-porous surface and high hydrophilicity were fabricated by addition of polyoxyethylene (40) nonylphenyl ether (igepal) as an additive in the casting solution. the membranes were prepared from pan/igepal/1-methyl-2-pyrrolidone (nmp) via phase inversion induced by immersion precipitation technique. pure water was used as coagulation medium. the effects o...

PURPOSE To investigate the effect of prostaglandins (PGs) on the permeability of human sclera in vitro. METHODS Twenty-three pairs of human eye bank eyes were studied. Circular pieces of sclera were cultured in low-serum DMEM/F-12 media. Scleral hydration was assessed by measuring wet and dry weight of scleral cultures incubated with medium for 3 days and with Hanks' buffered saline solution ...

We consider the behavior of immiscible and incompressible two-phase ows in a porous medium made of several rock types. Each rock type, is deened by one porosity, one absolute rock permeability ten-sor, two relative permeability curves and one capillary pressure curve. Using two-scale convergence, we get an homogenized model which governs the global behavior of the ow. In this model, macroscopic...

9. Accumulation of glutamate also occurred in isolated kidney cortex, spleen, lung and chorion. Six other tissues examined maintained a concentration gradient between tissue and medium, but did not increase the glutamate concentration above the original level. 10. It is pointed out that tissue slices afford a system in which problems of permeability and storage can be studied under controlled c...

In this paper, we present the calculation of the effective parameters of an artificial medium made of planar conducting obstacles. The evaluation of both the effective permittivity and of the effective permeability is addressed here. It is well known that this type of artificial medium exhibits anisotropy. One possible application for this artificial medium is the fabrication of non-homogeneous...

The retinal pigment epithelium (RPE) is an epithelial region of the blood-brain barrier. During embryogenesis, permeability of the barrier gradually decreases. A culture model of RPE development revealed differences in how tight junctions regulate the paracellular diffusion of ionic and nonionic solutes (Ban Y and Rizzolo LJ. Mol Vis 3: 18, 1997). To examine these differences, the permeation of...

Increased cerebrovascular permeability is an important factor in the development of cerebral edema after stroke, implicating the blood-brain barrier (BBB) in the pathology of stroke. Present investigations modeled stroke at the level of the cerebral capillary endothelium by analyzing BBB permeability changes to the membrane-impermeant marker [14C]sucrose after hypoxia/aglycemia. Under hypoxia a...