Application of perturbed angulary γ-ray correlations in medical chemistry

The principles are presented for the perturbed angular γ-ray correlation method, together with the specifications for the spectrometers and radioisotopes. Applications in medical chemistry are considered on the basis of experimental results. Translated from Izmeritel'naya Tekhnika, No. 5, pp. 56–64, May, 1999.     

B and also T lymphocytes migrate via gut lymph to all lymphoid organs and the gut wall, but only IgA+ cells accumulate in the lamina propria of the intestinal mucosa

In pigs the lymphocytes emigrating from the intestinal wall were collected by cannulating the lymphatics, labeled in vitro using a fluorescent dye and retransfused. The injection of 6.6+/-4.2 x 10(8) cells resulted in a labeling index between 1.5% in intestinal lymph, 0.2% in the spleen and lymph nodes, approximately 0.1% in the intestinal lamina propria and 0.003% in intraepithelial lymphocytes. About 25 % of the injected cells were present in the blood and 1 % was recovered in the lymph. T cells were found in similar proportions in the injected and the recovered cells in the organs (70-80%). The proportion of IgA+ cells among the immigrated cells in the intestinal lamina propria ranged from 5 to 8%, which in absolute numbers was up to 60% of the injected IgA+ cells. T and IgM+ cells did not show a higher accumulation in any organ. These experiments in conventional, unrestrained animals revealed that (1) T cells immigrate into the intestinal lamina propria, (2) preferential migration of IgA+ cells from gut lymph to the intestinal lamina propria is obvious under in vivo conditions and (3) the immigrated IgA+ cells represent a very small population which is difficult to detect when analyzed in relative numbers.     

Two Phase Flows in Porous Media Under Microgravity Conditions

The paper presents the results of investigating the instability of the displacement of viscous fluid by a less viscous one in two-dimensional and three-dimensional porous specimens. The effects of the three-dimensional phenomena on development of instability are revealed, in particular, the faster growth of 3D disturbances as compared with 2D ones, while 2D displacement integral parameters (such as the outflow of the displacing fluid) have much higher deviations than those parameters obtained in 3D modelling. This can be explained by much higher number of fingers in 3D cases of displacement reaching the outflow surface, and by the subsequent compensation of disturbances in the overall outflow.     

The effect of the alloying elements of a CoNiCrAlY system on the corrosion resistance of alloys for protective coatings of gas turbine blades

Results from testing for resistance to sulfide-oxide corrosion of model alloys used to make possible CoNiCrAlY system-based protective coatings are presented. The effect exerted by Ni, Cr, Al, and Y on the corrosion resistance of these coatings at different temperatures is determined, and equations for calculating the chromium equivalents of these coatings are obtained.     

The dislocation anharmonicity in silicon

The effect of the dislocation anharmonicity on the Young modulus in bending silicon single crystals was studied. It is shown that changes in the Young modulus are caused by the contribution of dislocations to the fourth-order elasticity moduli. It is revealed experimentally that the bending deformation in both donor and acceptor silicon crystals favors the appearance mainly of the edge dislocations with the axes forming an angle θ∼90° with the Burgers vector.     

Handling toxic wastes during salvaging and rehabilitation of nuclear objects in north-west Russia

Systematized information on toxic wastes produced during salvaging and rehabilitation of decommissioned nuclear and radiation-hazardous objects in the nuclear-powered naval fleet in north-west Russia is presented. The dynamics of their accumulation up to 2025 is estimated. Substantiation is given for the need to re-examine the existing system of handling wastes and searching for new solutions for decreasing the ecological risk by systematically reprocessing or eliminating them together with gaining an ecological advantage. Such an approach requires upgrading and developing infrastructure at the salvaging enterprises and objects undergoing rehabilitation. Several strategies are examined. The advantages and disadvantages of each strategy are evaluated according to safety and cost factors and the most acceptable strategy is chosen. A functional model is created. A list of projects and technical means is presented, and the time periods and costs required for implementation are estimated. The priority directions of work are identified. Translated from Atomnaya énergiya, Vol. 105, No. 6, pp. 345–352, December, 2008.     

Clinical manifestations and treatment of intestinal dysbacteriosis in patients with Flexner's dysentery

Flexner's dysentery is often accompanied with intestinal dysbacteriosis. Disbiotic changes in the intestine contribute to specific shigella endotoxins entering blood flow thus prolonging clinical symptoms of the underlying disease. Administration of bacterial biological preparations (bifidumbacterin forte, lactobacterin) relieves specific endotoxemia, reduces the duration of the disease and has an immunomodulating action.