Central Schemes for Nonconservative Hyperbolic Systems

In this work we present a new approach to the construction of high order finite volume central schemes on staggered grids for general hyperbolic systems, including those not admitting a conservation form. The method is based on finite volume space discretization on staggered cells, central Runge-Kutta time discretization, and integration over a family of paths, associated to the system itself, for the generalization of the method to nonconservative systems. Applications to the one and the two layers shallow water models as prototypes of systems of balance laws and systems with source terms and nonconservative products respectively, will be illustrated

Применение интерферометрического метода исследования в изучении кинетики реакций бромидов бария и рубидия с хлористым водородом

The two-layer shallow water system looses hyperbolicity if the mag- nitude of the shear velocity is above a certain threshold, which is es- sentially determined by the density difference between the two layers. The focus of the paper is to explore a technique to possibly recover hyperbolicity by adapting the model in regions of strong shear. The approach is to introduce an additional, third layer in such regions. We demonstrate that this adaptive two/three-layer approach can cure some of the shortcomings of the two-layer model but needs further improvement with respect to the model

NSP1B3 : un logiciel pour resoudre les equations de Navier Stokes incompressible 3D

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The correlation of RNase A enzymatic activity with the changes in the distance between Nepsilon2-His12 and N delta1-His119 upon addition of stabilizing and destabilizing salts.

The effect of stabilizing and destabilizing salts on the catalytic behavior of ribonuclease A (RNase A) was investigated at pH 7.5 and 25 degrees C, using spectrophotometric, viscometric and molecular dynamic methods. The changes in the distance between N(epsilon2) of His(12) and N(delta1) of His(119) at the catalytic center of RNase A upon the addition of sodium sulfate, sodium hydrogen sulfate and sodium thiocyanate were evaluated by molecular dynamic methods. The compactness and expansion in terms of Stokes radius of RNase A upon the addition of sulfate ions as kosmotropic salts, and thiocyanate ion as a chaotropic salt, were estimated by viscometric measurements. Enzyme activity was measured using cytidine 2', 3'-cyclic monophosphate as a substrate. The results from the measurements of distances between N(epsilon2) of His(12) and N(delta1) of His(119) and Stokes radius suggest (i) that the presence of sulfate ions decreases the distance between the catalytic His residues and increases the globular compactness, and (ii) that there is an expansion of the enzyme surface as well as elongation of the catalytic center in the presence of thiocyanate ion. These findings are in agreement with activity measurements

Trends in liver transplantation for primary biliary cirrhosis in the Netherlands 1988-2008

Background: A decrease in the need for liver transplantations (LTX) in Primary Biliary Cirrhosis (PBC), possibly related to treatment with ursodeoxycholic acid (UDCA), has been reported in the USA and UK. The aim of this study was to assess LTX require

Current progress on the numerical simulation of detached flows around airplanes

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