Metabolism, intensity of lipid peroxidation and the antioxidant defense system in humans during chamber experiments with long-term isolation

Blood biochemical parameters of lipid, protein, carbohydrate and energy metabolism were measured in a 135-day chamber experiment. Also, dynamics of the intensity of lipid peroxidation and status of the antioxidant defence system were evaluated. Results of the investigation showed that extended chamber isolation led to modifications of several biochemical parameters including hemoglobin, bilirubin, cholesterol and its fractions, elevated transaminase activity which are typical for long-term space mission. However, these were not accompanied by substantive changes in protein, energy and carbohydrate metabolisms, or intensity of free radical processes. Effects of prolonged stay in chamber was successfully counterbalanced by organism.     

Vasoactive properties of various fragments of human alpha-calcitonin gene-related peptide

Effects of some fragments of alpha-calcitonine gene-related peptide (alpha-CGRP) on the collector lymphatic vessels of the rat small intestine mesenterium, were studied. All the fragments excepting alpha-CGRP (21-24) and (21-31) activate motility of the lymphatic vessels enhancing phasic contractions of the walls. Presence of aminoacid residuals in the 20-29 area is "critical" for realising vasoactive properties by these fragments.     

Direct Simulation of Moderately Rarefied Gas Flows in Two-Dimensional Model Porous Media

The applicability of a quasi-hydrodynamic system of equations to the simulation of moderately rarefied gas isothermal flows in two-dimensional domains with a complex geometry typical for pore spaces of rock samples is numerically studied. In order to take into account gas slippage effect on the solid boundaries the classical Maxwell slip boundary conditions are used, for which an approximation is proposed and the implementation algorithm is described. The simulation results are presented for several samples under different average pressure values. A qualitatively correct dependence of the Klinkenberg slip factor on the ratio of the absolute permeability coefficient to the sample porosity is revealed.     

Thermal-hydraulic tests of a recirculation cooling installation for the Rostov nuclear power station

Results obtained from thermal-hydraulic tests of the recirculation cooling installation used as part of the air cooling system under the containments of the Rostov nuclear power station Units 3 and 4 are presented. The operating modes of the installation during normal operation (air cooling on the surface of finned tubes), under the conditions of anticipated operational occurrences (air cooling and steam condensation from a steam-air mixture), and during an accident (condensation of pure steam) are considered. Agreement is obtained between the results of tests and calculations carried out according to the recommendations given in the relevant regulatory documents. A procedure of carrying out thermal calculation for the case of steam condensation from a steam-air mixture on the surface of fins is proposed. The possibility of efficient use of the recirculation cooling installation in the system for reducing emergency pressure under the containment of a nuclear power station is demonstrated.     

Scanning electron microscopic method for studying the interaction of normal peritoneal macrophages with tumor cells

It is shown that the damage action of normal peritoneal macrophages of mice includes inhibition of the proliferating activity of the mastocytoma P-815 cells and their complete destruction accompanied by the breaks of their cytoplasmic membrane. Scanning electron microscopy was used to reveal two types of contacts between peritoneal macrophages and cells P-815; the loss of microvilli and the appearance of blebs on cell surface in the case of adsorption of P-815 cells on macrophages; the contact through long filopodia which are sent forth by macrophages in the case when contacting cells are at some distance from each other.     

Influence of superconducting magnet winding structure on conductor cryostability

The influence of the volume of the superconducting winding interlayer space and the structure of the insulation coating upon the conductor recovery current value I_r has been investigated experimentally. An analysis of the optimum conductor insulation coating was performed, considering different forms of an organic fibre net. The optimum thickness and cell dimension of the net were chosen based on the I_r measurements. It has been shown that the optimal volume of interlayer cooling channels increases the conductor cryostability, and creation of additional gaps of 200 μm in the winding spacers is able to intensify the heat transfer.