Coralline Skeleton Biomaterial Reduces Phagocytosis in Mouse Blood in vitro

Inflammatory and immunogenic response to foreign bodies presents a challenge in the use of biomaterials as implants for tissue restoration. Therefore, there is a need to understand the interactions between such implants and the blood. One such material, currently in clinical use for bone replacement in humans, is the skeleton of corals, in the form of crystalline aragonite. This biomaterial has been shown to impart a protective and supportive influence on several types of cells ex vivo. The carbonate skeleton activates secretion in phagocytes in vitro, however its effects on these cells in the blood, and on the process of phagocytosis itself, remain unknown. Using 1–500 μm particles of coral skeleton, we show that these particles bind blood proteins and alter the leukocyte population, reducing the proportion of granulocytes by more than 3-fold with no effect on the proportion of monocytes. In addition, the presence of coral skeleton in the blood causes a reduction in phagocytosis. Specifically, we observed a decrease in the percentage of phagocytic cells by 27 % in the granulocytes and by 73 % in monocyte family, as well as a 41.6 % reduction in the MFI of granulocytes, but with no such effect on monocytes. Taken together, the results suggest that the coral skeleton biomaterial may act as a strong, promotive scaffold for tissue regeneration due to its ability to reduce its rejection by inflammatory reactions such as phagocytosis.     

Mathematical Model of Heat Transfer in a Solar Collector and Its Experimental Validation

A mathematical model is proposed for heat transfer in a system involving a solar collector and a heat exchanger. An analytical solution is obtained for the problem of heat conduction through the collector wall under the Cauchy boundary conditions with regard for internal heat sources due to the solar energy flux. A schematic of an experimental setup involving a Solahart solar collector is presented, in which solar radiation heats a heat-transfer medium flowing by gravity. The observed temperatures of the heat-transfer medium at the collector outlet agree satisfactorily with those calculated within the proposed model.     

Mathematical Model of Synthetic Leather Drying

A mathematical model of synthetic leather drying for removing the organic solvent is proposed. Analytical solutions are obtained for a number of problems of heat transfer in a plate, including the problem of a moving evaporation front. The model proposed adequately describes the real processes.     

Heat transfer under natural convection of liquid metal during its boiling in a system of channels

We describe an experimental installation, a model, a test procedure, and results from experimental investigations into hydrodynamics and heat transfer during the boiling of an eutectic sodium-potassium alloy in a system of two parallel channels that simulate the operating conditions of channels in a typical fast-neutron reactor.     

Helical magnetic configurations with minimum\bar B

A general consideration of magnetic configurations with helical symmetry and minimum is presented. An approximate analytic expression is obtained for the specific volume V'() in the neighborhood of the helical magnetic axis. Exact formulas for the specific volume V'() and the mean torsional angle of the lines of force i=2X'() are given in terms of single integrals. Graphs of V'() and X'() are plotted from numerical calculations of these integrals up to the separatix of the magnetic surfaces.Translated from Atomnaya Énergiya, Vol. 20, No. 5, pp. 396–401, May, 1966.