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The methods of optical microscopy, x-ray phase analysis and microindentation are used to study the effect of vacuum annealing at 750, 800 and 850°C on the structure, phase composition and microhardness characteristics over cross section of welded joints of unlike alloys OT4 – VT6, VT20 – VT6 and VT23 – VT6. Recommendations are developed on the temperature of vacuum annealing of the welded compositions studied, which provide gradual variation of the hardness parameters in welded joints upon transition from the matrix metal of one alloy to the other.

A range-wide phylogeographic study of the common shrew Sorex araneus was performed using the concatenation of cytb and ND2 mitochondrial genes. The data support two major lineages, one of which (European haplogroup) is distributed continuously from West Europe to West Siberia; the other (Siberian haplogroup) is found in two non-adjacent areas: in central Siberia and in southern Finland and Karelia. Several smaller subclades (East European, Balkan, and West Siberian) were identified within the European lineage. Ancestral area reconstructions were performed under the maximum parsimony criterion using the algorithm that was designed to analyze landmark data. The results suggest that the last common ancestor of the common shrew inhabited the Balkans or the Danubian-Carpathian area. The results of demographic analyses are consistent with the hypothesis of recent expansion throughout the entire distribution range. The genetic diversity indices and the expansion time estimates were higher in the western part of the range. Cumulatively, these findings support the hypothesis that during the Last Glacial Maximum, the range of the common shrew was restricted to a single refugium in Southeastern Europe.

The methods of optical and scanning electron microscopy, microhardness measurement, differential scanning calorimetry (DSC), dilatometry, dynamic mechanical analysis, and hydrostatic weighing are used to study the structure and the physical and mechanical properties (density, microhardness, modulus of elasticity, coefficient of linear thermal expansion) of cold-deformed brass LS59-1 in the initial condition and after heating to 800°C. The DSC heating curve exhibits exo- and endothermic effects due to stress relaxation and retrogression (the exothermic effect at 115 – 235°C), melting of lead segregations (the endothermic effect at about 328°C), transition of the β′-phase into a disordered β -condition (the endothermic effect with minimum at 458°C), and transition of the brass into a single-phase β -condition (the endothermic effect at 642 – 747°C with minimum at 721°C).

Regular features of variation of structure, phase composition and hardness characteristics in a β-phase-based titanium alloy Ti – 10 V – 2Fe – 3Al subjected to isothermal treatment in a melt of lead and tin for 5 sec – 32 h at 250 – 800 °C after a hold at 860 °C are considered. The types of the phases precipitated in the process of isothermal decomposition of the high-temperature β-solid solution and the dependences of the lattice constant of the β-phase and of the hardness on the temperature-and-time mode of the treatment are determined. Adiagram of isothermal decomposition of the β-solid solution in alloy Ti – 10 V – 2Fe – 3Al is plotted.

Potassium voltage-gated Kv1.6 channel, which is distributed primarily in neurons of central and peripheral nervous systems, is of significant physiological importance. To date, several high-affinity Kv1.6-channel blockers are known, but the lack of selective ones among them hampers the studies of tissue localization and functioning of Kv1.6 channels. Here we present an approach to advanced understanding of interactions of peptide toxin blockers with a Kv1.6 pore. It combines molecular modeling studies and an application of a new bioengineering system based on a KcsA-Kv1.6 hybrid channel for the quantitative fluorescent analysis of blocker-channel interactions. Using this system we demonstrate that peptide toxins agitoxin 2, kaliotoxin1 and OSK1 have similar high affinity to the extracellular vestibule of the K+-conducting pore of Kv1.6, hetlaxin is a low-affinity ligand, whereas margatoxin and scyllatoxin do not bind to Kv1.6 pore. Binding of toxins to Kv1.6 pore has considerable inverse dependence on the ionic strength. Model structures of KcsA-Kv1.6 and Kv1.6 complexes with agitoxin 2, kaliotoxin 1 and OSK1 were obtained using homology modeling and molecular dynamics simulation. Interaction interfaces, which are formed by 15-19 toxin residues and 10 channel residues, are described and compared. Specific sites of Kv1.6 pore recognition are identified for targeting of peptide blockers. Analysis of interactions between agitoxin 2 derivatives with point mutations (S7K, S11G, L19S, R31G) and KcsA-Kv1.6 confirms reliability of the calculated complex structure.

The effect of microalloying with yttrium and zirconium in the amount of 0.06 and 0.07 wt.% respectively on the formation of structure, phase composition and measured hardness characteristics of a two-phase titanium alloy of the Ti – Al – Mo – V – Cr – Fe system is studied. The laws of variation of the phase composition and structure of the alloy with microadditives in the temperature range of 700 – 950°C and during subsequent cooling in water and air are determined. The diagram of variation of the phase composition of the alloy under water quenching is plotted.

Migraine is a complex brain disorder, and understanding the complexity of this prevalent disease could improve quality of life for millions of people. Familial Hemiplegic Migraine type 2 (FHM2) is a subtype of migraine with aura and co-morbidities like epilepsy/seizures, cognitive impairments and psychiatric manifestations, such as obsessive-compulsive disorder (OCD). FHM2 disease-mutations locate to the ATP1A2 gene encoding the astrocyte-located α2-isoform of the sodium-potassium pump (α2Na+/K+-ATPase). We show that knock-in mice heterozygous for the FHM2-associated G301R-mutation (α2+/G301R) phenocopy several FHM2-relevant disease traits e.g., by mimicking mood depression and OCD. In vitro studies showed impaired glutamate uptake in hippocampal mixed astrocyte-neuron cultures from α2G301R/G301R E17 embryonic mice, and moreover, induction of cortical spreading depression (CSD) resulted in reduced recovery in α2+/G301R male mice. Moreover, NMDA-type glutamate receptor antagonists or progestin-only treatment reverted specific α2+/G301R behavioral phenotypes. Our findings demonstrate that studies of an in vivo relevant FHM2 disease knock-in mouse model provide a link between the female sex hormone cycle and the glutamate system and a link to co-morbid psychiatric manifestations of FHM2.

Artificial soil compositions have been used as substrates for growing plants on the basis of modified polyacrylonitrile (PAN) fibers and films of sodium alginate. The agrophysical characteristics of these artificial substrates based on modified PAN fibers indicate that such composites have low volume mass, high water capacity, and a good level of capillary water rise. These artificial substrates provide for normal plant development. At the end of the experiments, the root systems of grasses had penetrated the substrates, which provided for firm plant embedding. Most of the parameters for grass on artificial substrates correspond to those for grass grown on natural soil, and in some cases even exceed those results. The best results are obtained with fibers modified by urea (PAN-KA), because urea acts as a nutrient during growth. Artificial soils containing alginate films bearing mineral nutrients have also given good results. In that case it is possible to mount the seeds directly on the film, which provides for convenient transportation and facilitates planting.

The neural circuits mediating fear to naturalistic threats are poorly understood. Here we demonstrate that functionally independent populations of neurons in the ventromedial hypothalamus (VMH), a region implicated in feeding, sex, and aggression, are essential for predator and social fear in mice. Our study establishes a critical role for VMH in fear and carries implications for the selective intervention in pathological fear in humans.

The microstructure of a mixture for gasless combustion and its compactability were studied. The electrical conductivity, thermal conductivity, and burning rate of the mixture were measured, and metallographical studies were performed. It was found that particle shape and the ability of the particles to form a continuous skeleton play a determining role in the gasless combustion of the mixture. Accounting for this fact allows one to explain some experimental results that are inconsistent with the conventional theory of gasless combustion.

Ti–Al multilayer foils were produced magnetron vacuum deposition. The microstructure period varied in the range of 5–110 nm, the number of layers was 150–4700, and the total thickness of a multilayer foil reached 15–20 μm. The gasless combustion of the foils was studied. Steady‐state and pulsating combustion regimes were revealed; combustion temperatures were determined for both regimes. It was shown that the most probable mechanism of the self‐propagating reaction is the diffusion of Al in β‐Ti at a temperature close to the temperature of the α → β transition.

The structure of the composite viscose—polyester fibre examined allows processing textile articles with high physicomechanical indexes combined with good hygienic and comfort properties. Polynomial models that satisfactorily reflect the dependence of optimization criteria on the process parameters in production of composite viscose—polyester fibres are obtained. The analysis of the models allows establishing the optimum process parameters for processing composite viscose—polyester fibres for mass market consumer goods; K 1 = 480 tw./m, K 2 = 320 tw./m, P = 20 cN.

The method of polymerase chain reaction with a set of arbitrary primers (RAPD–PCR) was used to describe genetic variation and to estimate genetic diversity in East-European windhounds, Russian Borzoi and Russian Chortai. For comparison, windhounds of two West-European breeds (Whippet and Greyhound) and single dogs of other breed types (shepherd, terriers, mastiffs, and bird dogs) were examined. For all dog groups, their closest related species, the wolf Canis lupus, was used as an outgroup. Variation of RAPD markers was studied at several hierarchic levels: intra- and interfamily (for individual families of Russian Psovyi and Chortai windhounds), intra- and interbreed (for ten dog breeds), and interspecific (C. familiaris–C. lupus). In total, 57 dogs and 4 wolves were studied. Using RAPD–PCR with three primers, 93 DNA fragments with a length of 150–1500 bp were detected in several Windhound families with known filiation. These fragments were found to be inherited as dominant markers and to be applicable for estimation of genetic differences between parents and their offspring and for comparison of individuals and families with different level of inbreeding. A high level of intra- and interbreed diversity was found in Russian Borzoi and Russian Chortai. In these dogs, genetic similarity indices varied in a range of 72.2 to 93.4% (parents–offspring) and 68.0 to 94.5 (sibs). Based on the patterns of RAPD markers obtained using six primers, a dendrogram of genetic similarity between the wolf and different dog breeds was constructed, and indices of intragroup diversity were calculated. All studied breeds grouped into two clusters, windhounds (Borzoi-like dogs) and other dog breeds. Russian windhounds represent a very heterogeneous group, in which the Russian Borzoi is closer to Greyhound than the Russian Chortai. All studied wolves constituted a separate cluster. Significant differences were found between the wolf and dogs by the number of RAPD markers (92.8 and 86.1, respectively) and by the indices of genetic diversity (54.3 and 64.8%, respectively). The reason for the high intraspecific variation of dogs (including Russian windhounds) and the prospects of using the studied group of markers for genetic analysis and differentiation in C. familiaris are discussed.

A transcript containing the long terminal repeat (LTR) and the sequence homologous to the KIAA1245 mRNA fragment were revealed among the transcribed LTRs of human endogenous retroviruses of the K family in normal and tumor tissues. Ten other sequences with a high level of homology to the KIAA1245 mRNA were found in the GenBank. The intron–exon structures were determined for all the sequences, and their exon sequences were compared. The comparison showed that they differ both in the extent of their exon homology and in the presence or absence of the HERV-K LTR in the third intron. The revealed sequences form a new gene family that comprises at least four subfamilies. Two of these subfamilies have the LTR, and the other two do not. We showed by PCR that the LTR was integrated into the introns after the divergence of the orangutan evolutionary branch from other hominoids but before the divergence of the gorilla branch, i.e., 8–13 million years ago.

Magnetic storm modulates morphological and functional state of the heart and the related systems. Changes in cardiomyocyte ultrastructure induced by changes in geomagnetic activity were studied in experiments on rabbits. We describe a possible mechanism underlying changes in cardiac activity in intact animals induced by geomagnetic perturbations. The most pronounced alterations of cardiomyocyte ultrastructure were observed during the major phase of magnetic storm.

Use of the equations of G. V. Sokolov for calculating the optimum spindle rotation rate as a function of the linear density of the processed fibres and threads does not allow obtaining objective values at present. Refined equations were obtained for calculating the optimum spindle rotation rate on ring twisting frames which give values close to the production values. The constant numerical factor is replaced by the equations, which describe the character of the change in the twisting conditions on ring twisting frames more completely and correctly. The refined empirical equations can be recommended for use in engineering calculations and in design engineering.

The properties of chitosans of different origin and with a different degree of deacetylation were evaluated and the rheological properties of solutions of them in 2% acetic acid were investigated. Technological regimes for fabrication of film, fibre, and porous materials from the natural polysaccharide chitosan were proposed. The properties of the materials obtained were investigated.

A unified procedure was developed for the spectrophotometric determination of pyrazidole in the medicinal substance and in tablets using phenolphthalein or benzoic acid as reference samples. The best conditions for the determination have been found as follows: 0.1 M HCl as a solvent and an analytical wavelength of 276 nm. The scaling factors have been determined. Calibration equations are given. The relative standard deviations of the results obtained with the proposed procedure are less than 0.5% for the substance and 3.3% for tablets.

A highly sensitive and selective procedure was developed for determining specific impurities of isonicotinic acid hydrazide and vanillin in Metazid and Ftivazide preparations by thin-layer chromatography.

A rat model of D-galactosamine-induced (0.3 g/kg) liver damage is used to study antioxidant and membrane-stabilizing activity of sodium selenite, vitamin E, and their combination (administeredper os, daily, for 3 days before intoxication). It is shown that sodium selenite is 300-fold more effective than vitamin E, while their combination exhibits synergism and potentiation of the antioxidant and membrane-stabilizing activities, underlying inhibition of hepatocyte cytolysis.

A procedure was developed for preparing alginate fibers with controllable calcium content. The effect of ethonium and Katamin AB on desorption of calcium ions from the alginate fiber was studied.

The use of composite viscose—polyamide and viscose—polyester fibres significantly improves the comfort properties of fabrics and knits. The sorption power of the composite fibres is higher the higher the viscose component content is, since polyester and polyamide fibres are almost nonhygroscopic. Increasing the relative humidity from 66 to 98% increases the moisture content of these fibres by 2-3 times.

1. It was shown that trypsin forms complexes with vinylpyrrolidone-vinylamine copolymers, polyvinylimidazole, and poly(2-methyl-5-vinylpyridine) at a pH below its isoelectric point. The role of electrostatic interaction in the complexing process was ascertained. 2. The bonding with polybases of variable structure does not lower the trypsin activity and does not involve its native structure. A stabilization of trypsin under the conditions of the autocatalytic process, and also during heat and acid-base denaturation, is observed here. 3. The stabilizing capacity of the polymers is substantially higher than that of the corresponding monomeric bases (imidazole and N-ethylimidazole). 4. A method was proposed for approximately estimating the complexing constants in the investigated systems. The effect of the pH of the medium on the bonding constant of trypsin with poly(N-vinylimidazole) was studied.

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