Influence of critical hypotension on the development of postoperative hepatic failure

The article is devoted to the study of influence of critical hypotension on the development of postoperative hepatic failure. The results of treatment of 54 patients who had. anatomical and advanced anatomical resections of a liver were analyzed. Also the causes that lead to the postoperative hepatic failure such as volume of intraoperative blood loss, duration of intraoperative hypotension were analyzed. As the result of the analysis of obtained data on the influence of studied parameters (volume of blood loss, duration. of vascular isolation and presence of intraoperative hypotension) on the development of hepatic failure in postoperative period we supposed that the most unfavorable prognostic sign of its appearance is an episode of critical decrease of arterial pressure during the operation. Thus even at massive blood loss hepatic failure doesn't always appear, whereas critical intraoperative hypotension causes its development. Taking into consideration data on the state of central hemodynamics at the performing of anatomic resections of liver we determined main approaches to the infusion-transfusion therapy during excluding of liver from blood circulation for the prophylactics of its reperfusion injuries. It was established that prophylactics and timely correction of critical intraoperative hypotenstion that is the main factor of development of postoperative hepatic failure should be considered as the key moments of intraoperative protection of hepatocytes

Возможности использования Интернет при обучении иностранному языку

The possibilities of using Internet in teaching foreign languages in technical institutes are represented. Each stage of educational project aimed to develop communicative competence is considered. The peculiarities of teaching process with using Internet are taken into account.Представлены возможности использования Интернет при обучении иностранному языку в неязыковом вузе. Поэтапно рассмотрен учебный проект, нацеленный на развитие коммуникативной компетенции. В статье учитываются особенности учебного процесса с применением Интернет

Mechanical Analogy-based Iterative Method for Solving a System of Linear Equations

The paper reviews prerequisites to creating a variety of the iterative methods to solve a system of linear equations (SLE). It considers the splitting methods, variation-type methods, projection-type methods, and the methods of relaxation.A new iterative method based on mechanical analogy (the movement without resistance of a material point, that is connected by ideal elastically-linear constraints with unending guides defined by equations of solved SLE). The mechanical system has the unique position of stable equilibrium, the coordinates of which correspond to the solution of linear algebraic equation. The model of the mechanical system is a system of ordinary differential equations of the second order, integration of which allows you to define the point trajectory. In contrast to the classical methods of relaxation the proposed method does not ensure a trajectory passage through the equilibrium position. Thus the convergence of the method is achieved through the iterative stop of a material point at the moment it passes through the next (from the beginning of the given iteration) minimum of potential energy. After that the next iteration (with changed initial coordinates) starts.A resource-intensive process of numerical integration of differential equations in order to obtain a precise law of motion (at each iteration) is replaced by defining its approximation. The coefficients of the approximating polynomial of the fourth order are calculated from the initial conditions, including higher-order derivatives. The resulting approximation enables you to evaluate the kinetic energy of a material point to calculate approximately the moment of time to reach the maximum kinetic energy (and minimum of the potential one), i.e. the end of the iteration.The software implementation is done. The problems with symmetric positive definite matrix, generated as a result of using finite element method, allowed us to examine a convergence rate of the proposed method. The proposed method has shown the comparable results with the most commonly used method of conjugate gradients. There are prospects for development of the proposed method, in particular through the preconditioned use.</p