The results of studies of epididymal spermatozoa of three species of rodents (bank vole
Clethrionomys glareolus
, northern red-backed vole
Cl. rutilus
, and herb field mouse
Sylvaemus uralensis
) ...living under long-term exposure to atmospheric emissions from two large copper smelters in the Middle Urals are summarized (Middle Ural and Kirovgrad copper smelters). The impact of pollution (including at the individual level on the accumulation of Cu, Zn, Pb, and Cd in the liver) was assessed for indicators characterizing the quality of sperm from different aspects: morphology (proportion of cells with head and tail defects), motility (proportion of motile cells, velocity, and straightness of movement) and concentration. Sperm motility responds to pollution: in impact zones, the proportion of motile cells and their velocity were lower than in background zones. The occurrence of abnormal cells and sperm concentration were not statistically significantly different between impact and background zones. The reaction of sperm to chemical pollution is species-specific: voles react more strongly than the herb field mouse. The consistency of changes in sperm parameters (in the direction of their deterioration) in response to increased pollution was found only in the bank vole. Effect sizes for sperm parameters are much smaller compared to those for liver Cd accumulation and animal abundance. In general, the reaction of sperm to pollution turned out to be weak, none of the studied indicators can be a reliable marker of industrial pollution.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The levels of interspecific and intraspecific variation in morphometric parameters of spermatozoa have been studied in seven wild rodent species of the families Cricetidae and Muridae and inbred CBA ...mice. The study of intraspecific variability of parameters included an analysis of within-population age-related variation and variation among individuals within a population. It has been found that, as expected, animal species is the factor contributing most to variation in the test parameters, but the degree of differences between species has been not always proportional to genetic distances between them. The proportion of within-population age-related variation is not significant and, hence, can be ignored in population studies on male reproduction. In contrast, the contribution of individual variation in the parameters of spermatozoa to their overall variation in each species is significant and should be taken into account when forming the samples and analyzing the results. The levels of intraspecific variation in the morphometric parameters of spermatozoa in wild rodents and inbred mice are similar to each other.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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Data are presented on the long-term population dynamics of small mammals (1982–2019) and variation in the body weight and length of the bank vole, a dominant species, in southern taiga forests of ...the Middle Urals. Spontaneous change in the pattern of dynamics observed in our previous study—transition from regular 3-year cycles to noncyclic regime—provided the possibility to estimate the influence of different factors on the Chitty effect (increase in body size at high population numbers) under different regimes. This effect was clearly manifested in the bank vole population with cyclic dynamics: the average body weight and length of the animals were greater at the phases of population growth and peak than at the trough (low) phase, while the same parameters of voles from the noncyclic regime had intermediate values. The body size of animals depends not so much on population density as on factors determining their physiological status (including reproductive status).
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Original analytical data on trace elements and radiogenic Nd and Pb isotopes in the volcanic rocks of the Southern and southwestern part of the Northern plateaus of the underwater Vityaz Ridge are ...presented. Interpretation of these data and a comparison with published materials on the volcanic rocks from the southern and northern parts of the Kuril Island Arc (KIA), which formed on two basement blocks of different genetic nature, allow us to draw the following conclusions. The tholeiite varieties of volcanic rocks of the Southern Plateau and the southern part of the KIA have similar isotope-geochemical features, which point to the similar geodynamic conditions of the formation and the identical influence of low-temperature fluid on magma-generating processes. The geochemistry of the volcanic rocks of the Northern Plateau, which are mainly represented by subalkaline varieties, indicates a more pronounced contribution of the mantle component to the magmagenesis and a greater degree of influence of high-temperature melt compared to the rocks of the Southern Plateau, but a lesser degree compared to the rocks of the northern part of the arc. The volcanics of both plateaus are derivatives of a single mantle source, the MORB of the Indian Ocean (Indian MORB), and were formed together with the rocks of the southern part of the KIA within the lithospheric block transformed by tectonomagmatic processes that accompanied the opening of the Kuril Basin.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The effect of bioresorbable materials on aging in cultured mouse NIH 3T3 fibroblasts treated with elevated glucose concentration was investigated. The cells were grown on films produced from the ...silkworm fibroin and rS1/9, a recombinant analog of
Nephila clavipes
spidroin 1. Exposure to 50 mM glucose of the cells grown on uncoated glass support resulted in the cell growth retardation. The average areas of the cells and nuclei and the percentage of apoptotic cells increased, whereas the amount of soluble collagen decreased. In contrast, on the fibroin and spidroin films, the cell density and the percentage of 5-bromo-2′-deoxyuridine (BrdU)-positive cells were higher vs. the cells grown on the glass support. The films protected NIH 3T3 fibroblasts from the glucose-induced death. The most prominent effects on the cell density, BrdU incorporation, and apoptosis prevention were observed in the cells cultured on spidroin films. Unlike the cells grown on glass support (decrease in the soluble collagen production) or fibroin (no effect), production of soluble collagen by the cells grown on spidroin films increased after cell exposure to 50 mM glucose. Molecular analysis demonstrated that 50 mM glucose upregulated phosphorylation of the NFκB heterodimer p65 subunit in the cells grown on the glass support. The treatment of cells grown on fibroin films with 5.5 mM or 50 mM glucose had no effect on p65 phosphorylation. The same treatment decreased p65 phosphorylation in the cells on the spidroin films. These results demonstrate the anti-aging efficacy of biomaterials derived from the silk proteins and suggest that spidroin is more advantageous for tissue engineering and therapy than fibroin.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The key role of asthenospheric diapirism in the origin of the diffusive boundary of isotopic reservoirs of the Indian and Pacific MORB types was shown on the basis of high-precision Pb data. In view ...of the fact that the described processes are not unique for the zones of convergence, they have to be considered in modeling the formation of the juvenile continental crust.
The study analyzes the areas of cooperation between Russia and Kazakhstan within the framework of Eurasian integration.
Aim.
To identify the presence of factors contributing to the strengthening of ...relations between Russia and Kazakhstan at the present stage and obstacles hindering the deepening of integration processes.
Tasks.
To analyze the current state of cooperation between the two countries within the framework of the Eurasian Union, to identify obstacles to deepening integration processes, to show forecast scenarios of interaction between Russia and Kazakhstan. To analyze how these scenarios will affect the relationship between the two countries, and what consequences will be if each of them is implemented.
Methods.
The article uses general scientific methods of analysis and synthesis, a systematic approach, as well as an empirical method of expert evaluation.
Results.
The study showed that there are strong relations between the two countries in the economic sphere within the framework of the EAEU. Russia is the main trading partner of Kazakhstan. Projects related to the Caspian Sea are being developed and look very promising. Joint military exercises and supplies of Russian weapons are of great interest to Kazakhstan. Russia acts as a guarantor of Kazakhstan’s security in the region and its main partner in the Eurasian space. The Collective Security Treaty Organization also plays an important role in the relations between the two countries, which proved its effectiveness in the January 2022 events, contributing to the resolution of the political crisis and preventing extremist actions of armed terrorist groups. At the same time, the role of Kazakhstan as its closest neighbor and ally is also important for Russia, especially in the context of escalating international tensions.
Conclusions.
Both Russia and Kazakhstan are interested in further cooperation in the economic, military and cultural spheres. At the same time, the further deepening of integration processes is hindered by the absence of large joint investment projects and the multi-vector nature of Kazakhstan’s foreign policy. In the context of the information war of the West against Russia and the increasing international tension, it is extremely important to deepen cooperation between the two countries.