Using quantitative double-tracer autoradiography, we examined the tolerance of the rat cerebral venous system in focal cerebral ischemia to retrograde perfusion pressure into the inferior cerebral vein. At perfusion pressures of less than 150 mm Hg, there was no significant change in local cerebral blood flow (LCBF) and blood-brain barrier (BBB) permeability. At pressures of greater than 170 mm...

The effects of ionic strength of the permeating fluid on the clogging of soil filters and drainage layers are addressed using both experimental and modeling investigations. In the experimental phase, a sandy soil representative of soil filters was permeated with pore fluids containing kaolinite particles. The ionic strength of the solutions was changed using different concentrations of NaOH and...

The present study evaluated the effectiveness of a dicalcium and tetracalcium phosphate-based desensitizer in reducing dentin permeability in vitro. Dentin fluid flow was measured before and after treatment of dentin with patent dentinal tubules using 1 or 3 applications of the dicalcium and tetracalcium phosphate containing agent TeethmateTM (TM) and comparing the results with two sodium fluor...

Noll, T., H. Hölschermann, K. Koprek, D. Gündüz, W. Haberbosch, H. Tillmanns, and H. M. Piper. ATP reduces macromolecule permeability of endothelial monolayers despite increasing [Ca]i. Am. J. Physiol. 276 (Heart Circ. Physiol. 45): H1892–H1901, 1999.—We investigated the relationship between theATP-evoked rise of cytosolic Ca21 concentration ([Ca]i) and barrier function in porcine aortic endoth...

We conducted permeability measurements of basalt sampled from an exhumed ancient fault zone in the Cretaceous Shimanto accretionary complex in Japan, in order to investigate permeability structure and evolution following shear failure. Permeability showed a strong reduction with increase in the e#ective confining pressure and temperature. Rapid sealing at elevated temperatures was observed duri...

Microbial plugging has been proposed as an effective low cost method of improving sweep efficiency by reducing permeability of water-swept regions of a reservoir. To optimize the field implementation of this method, better mechanistic and volumetric understanding of biofilm growth within a porous medium is needed. In particular, the engineering design hinges upon a quantitative relationship bet...