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The article presents data on the genetic variability of the northern red-backed vole and the bank vole when inhabiting sympatrically in West Siberia. Two species of voles had comparable, relatively high indices of genetic variability of intermicrosatellite sequences of DNA. The proportion of polymorphic DNA markers was 95-98 %, Nei’s genetic diversity index - 0.33-0.35. In voles 47-58 % of allozyme loci were polymorphic, the average heterozygosity per locus was 0.058 in the northern red-backed vole, and 0.054 in the bank vole. Interpopulation differentiation in the red-backed vole ( FST = 0.293) was less compared to that in the bank vole ( FST = 0.475). Individuals of the hybrid line of the bank vole with mitochondrial haplotype of red-backed vole were found by the method of PCR-typing of cytochrome b gene fragment of mtDNA. The proportion of hybrid specimens ranged from 2 to 34 % in different regions. Indices of genetic variability in the hybrid line of the bank vole were lower than those of the parental species.

With a view to identifying interpopulational peculiarities of moor frog male growth and puberty, we have analyzed age composition, body sizes, and annual growth of amphibians inhabiting three water reservoirs with various hydrochemical composition. In all, 117 pubescent males aged from 2 to 6 were studied. As established, ambient surface water salinity in the Middle Urals is 150 mg/dm³ in the springtime. Interannual variations of salinity in the reservoirs under study are linked with changing sulphate content. It has been noted that water salinity up to 300 mg/dm³ during the spawning season shall not be viewed as a negative aspect restricting growth of moor frogs. Relatively early puberty of moor frog males occurs under close-to-optimal conditions and is followed by redistribution of energy towards reproductive processes along with growth retardation of amphibia.

Indicator values for Saussurea baicalensis (Adams) B. L. Rob., S. frolowii Ledeb., S. salicifolia (L.) DC., and S. schanginianа (Wydl.) Fisch. ex Serg. on the gradients of soil moisture and nutrient availability-salinity were analyzed for more than 1600 relevés. We determined the size of their ecological niches and their importance value in phytocenoses. We assessed the vulnerability of local populations of S. baicalensis, S. frolowii, S. salicifolia and S. schanginianа in the Kuznetsk Alatau by comparison of their position within the ecological niches and determined types of rarity for each of listed species in the Kuznetsk Alatau.

Currently, the natural zone of broad-leaved (nemoral) forests in Eurasia has a wide disjunction that falls on the most continental part of Siberia. However, there are several well-distinguished sites of high concentration (refugia) of nemoral relict species on the foothills of some mountains in South Siberia. The easternmost refugium is the northern macroslope of the Khamar-Daban Ridge. We analyzed present-day distribution of 27 nemoral relict plant species on the Khamar-Daban Ridge to detect the most probable Pleistocene microrefugia. Our results revealed that the microrefugia are most probably confined to the valleys of the Utulik, Babkha, Snezhnaya, Pereemnaya and Mishikha rivers. Based on the ranges of species within the distinguished microrefugia, six groups of relicts were identified. Evidently, species from those groups differed in their survival strategies during glaciations, as well as subsequent reexpansion during the interglacial time.

Fifteen Brunnera sibirica cenopopulations were studied. Morphological and genetic study revealed increase of variability and a high level of correlation of morphological features (together with decrease of sizes of vegetative organs) during the first years after deforestation in fir and aspen forests. High morphological and genetic diversity is typical of mountain fir forests, pine-birch and pine forests.

The impact of experimental high intensity fire on components of an ecosystem and post fire succession was studied in middle taiga of pine forest over 20 years. About 44 % of forest fuel loads burned down during the fire. The emission of carbon was about 18 t C/he. The trees died for the first three years after the fire and there was essential accumulation of fuel loads. Twenty years later the fuel loads exceeded that before the fire by four times, which opened up possibilities for repeat high-intensity fires. The initial stage of post fire succession is specified by forest growth conditions and occurs with change of dominants of herbaceous-dwarf shrub cover in the pine forest. The agrochemical and hydro-thermal soil indicators changed after fire, which promoted natural regeneration of pine trees enough for formation of forest stand.

This paper presents the results of an experimental study of the ignition and combustion of pyrotechnic compositions based on microsized and ultra-nanosized aluminum particles in a model two-zone gas generator in which water is supplied as the oxidizer. The flow of the combustion products from the gas generator was video recorded, and the condensed products sampled behind the nozzle exit were studied by chemical and grain-size analysis. It was found that the replacement of aluminum microsized particles by ultra-nanosized particles in the samples led to »17% decrease in the active aluminum content in the condensed phase, a 10-15 % increase in the efficiency of the process in the gas generator (completeness of conversion of the pyrotechnic composition to the combustion products), and a factor of about three decrease in the ignition delay.

A model for the spall fracture and compaction of a damaged material based on a description of the motion of a single pore is proposed. The model takes into account the strength properties, the effect of pressure, surface tension, and viscosity of materials and inertial forces. Equations describing the dynamics of growth and collapse of pores is presented. The proposed model can be used to calculate the spall fracture and compaction of liquids and metals, in both solid and liquid (molten) states.

A model for the penetration into a ceramic target with the formation of an expanding conical hole is proposed that can be used to determine the opening angle of the cone knocked out from the targets. The main cause of this fracture of ceramics is that the tensile strength of ceramic is much lower than its compressive strength. A method for calculating the maximum penetration velocity into a ceramic target without substrate was developed using the energy fracture criterion for ceramics. Two-dimensional numerical simulation of the impact of a steel projectile on a corundum plate showed satisfactory agreement between the calculated and experimental configurations of the resulting conical crack provided that the ratio between the compressive and tensile strengths is consistent with the recommendations of the developed model.

This paper describes the experimental and numerical study of the structures used for protection against the harmful effect of bullet and fission elements. A special place among them is taken by separated structures in which the gap between layers is filled with either air or various light materials with good damping, dissipative, and thermophysical properties. The results of the numerical simulation of the fragment of the separated protection are in good agreement with the experimental data on both residual forms and the size of deflections.