Application of the monte carlo method in the processing of experimental data on dynamic deformation of materials

The article presents a method of processing the recorded diagram of deformations vs time t for the purpose of determining the time-dependent change of strain rate and acceleration. The method is based on the utilization of data of statistical tests (the Monte Carlo method) and the least squares method applied to the deviations of the functions (t) from the experimental curve at the specified number of points.Translated from Problemy Prochnosti, No. 8, pp. 20–22, August, 1992.     

Therapeutic Effects of hiPSC-Derived Glial and Neuronal Progenitor Cells-Conditioned Medium in Experimental Ischemic Stroke in Rats

Transplantation of various types of stem cells as a possible therapy for stroke has been tested for years, and the results are promising. Recent investigations have shown that the administration of the conditioned media obtained after stem cell cultivation can also be effective in the therapy of the central nervous system pathology (hypothesis of their paracrine action). The aim of this study was to evaluate the therapeutic effects of the conditioned medium of hiPSC-derived glial and neuronal progenitor cells in the rat middle cerebral artery occlusion model of the ischemic stroke. Secretory activity of the cultured neuronal and glial progenitor cells was evaluated by proteomic and immunosorbent-based approaches. Therapeutic effects were assessed by overall survival, neurologic deficit and infarct volume dynamics, as well as by the end-point values of the apoptosis- and inflammation-related gene expression levels, the extent of microglia/macrophage infiltration and the numbers of formed blood vessels in the affected area of the brain. As a result, 31% of the protein species discovered in glial progenitor cells-conditioned medium and 45% in neuronal progenitor cells-conditioned medium were cell type specific. The glial progenitor cell-conditioned media showed a higher content of neurotrophins (BDNF, GDNF, CNTF and NGF). We showed that intra-arterial administration of glial progenitor cells-conditioned medium promoted a faster decrease in neurological deficit compared to the control group, reduced microglia/macrophage infiltration, reduced expression of pro-apoptotic gene Bax and pro-inflammatory cytokine gene Tnf, increased expression of anti-inflammatory cytokine genes (Il4, Il10, Il13) and promoted the formation of blood vessels within the damaged area. None of these effects were exerted by the neuronal progenitor cell-conditioned media. The results indicate pronounced cytoprotective, anti-inflammatory and angiogenic properties of soluble factors secreted by glial progenitor cells.     

Use of Corundum Ceramics for Fine Milling of Various Materials

The wear resistance of corundum milling bodies developed by the authors is estimated compared to foreign analogs. It is established that domestic ceramics, with respect to its abrasion rate in milling electrocorundum and quartz sand, is not inferior to foreign ceramics. The kinetics of milling the specified materials is analyzed.__________Translated from Steklo i Keramika, No. 1, pp. 17 – 18, January, 2005.     

Development of New Generation Ceramics for Their Potential Use in Domestic Industries

A brief survey of four groups of ceramic materials with a potential for effective use in science and technology is given. Durable ceramics based on Al₂O₃ and ZrO₂ are considered and areas of application are outlined. Corundum ceramics using eutectic additives that allow the sintering to be conducted at lower temperatures are discussed; structural features and properties of new materials and areas of application are considered. The use of porous ceramic materials for filtering cells and catalyst carriers is discussed. Bioceramics with a dense and porous structure based on hydroxyapatite that find ever-increasing interest for use in medicine are considered.     

Effect of Molecular Additives on the Ignition of Methane–Air Mixtures

Combustion, Explosion, and Shock Waves - The ignition of methane–air mixtures with additives of ClF5, ClF3, OF2, and H2O2 (additive content in the mixtures  $$\le$$ 1%) is studied by...