Changes in spike configuration and in the inward and outward currents of voltage-clamped axons agree in indicating that the increases in permeability to sodium and potassium ions during activity are depressed by procaine and cocaine and augmented by calcium. At low levels of depolarization, the effect of the multivalent ion is similar to that of the local anesthetics, in keeping with their simi...

Resistive-wall impedance usually constitutes a significant percentage of the total beam-coupling impedance budget of an accelerator. Reduction techniques often entail high electrical-conductivity coatings. This paper investigates the use of negative-permittivity or negative-permeability materials for sensibly reducing or theoretically nearly cancelling resistive-wall impedance. The proposed app...

Aqueous extracts of Acalypha langinia, Buddleia scordioides, Hylocereus undatus, Tecoma stans showed protective activity against the increased (both chloroform and histamine) skin vascular permeability in rabbits. The protective effect, measured as the reduction in leakage of Evans blue, were 90.2, 37.3, 43.5 and 69.3% respectively a dose of 250 mg/kg. Astianthus viminalis, showed only a 12.6% ...

Resistin has been linked to obesity, insulin resistance, atherosclerosis, and the development of cardiovascular disease. Nevertheless, the effects and the molecular mechanisms of resistin on endothelial permeability, a key event in the development of atherosclerosis, inflammation, and vascular disease, are largely unknown. In order to determine the effect of resistin on endothelial permeability...

Exogenous sphingosine-1-phosphate (S1P), a lipid mediator in blood, attenuates acute microvascular permeability increases via receptor S1P1 to stabilize the endothelium. To evaluate the contribution of erythrocytes as an endogenous source of S1P to the regulation of basal permeability, we measured permeability coefficients in intact individually perfused venular microvessels of rat mesentery. T...

photocatalytic membranes exhibit great potential for water treatment since they combine the filtration and photo degradation in a single unit. although blending photocatalytic nanoparticles into polymeric thin film remains the simplest method to prepare the photocatalytic membrane, the entrapped photocatalyst showed less catalytic activity due to the agglomeration and shielding effects in the p...

Enhanced oil recovery using nanoparticles is a promising method. However, when injected into reservoir, can block pores and cause permeability damage. Therefore, enhancing their performance to lower the damage effect crucial. This study investigated of pH alteration through carbon dioxide (CO2) injection on limestone caused by an aluminum oxide (α-Al2O3) nanofluid. The methodology involved nano...

Abstract. Mineral dissolution and precipitation can substantially affect rock permeability, which is a critical parameter for broad range of geological subsurface applications. Virtual experiments on digital pore-scale samples represent powerful flexible approach to understand the impact microstructural alterations evolving hydraulic behaviour quantify trends in permeability. In present study, ...

An index of pulmonary epithelial permeability has been studied in 12 patients with chronic renal failure during haemodialysis. It was assessed by the half time clearance from lung to blood (t 1/2 LB) of a nebulised solution containing technetium labelled diethylene triamine pentacetic acid (99mTc DTPA). Six patients were cigarette smokers and six were non-smokers. The non-smokers had greater pr...

Oxidants can reversibly increase the permeability of endothelium to ions and macromolecules. Oxidants also deplete ATP in cultured endothelial cells. We asked if oxidant-mediated ATP depletion, alone, accounted for the effects of oxidants on endothelial permeability to macromolecules. When porcine pulmonary artery endothelial cells were exposed to 2.5 mmol/LH2O2, ATP was depleted to 31.7% +/- 1...