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The aim was to study the distribution of macro-and microelements in the main urban ecosystems of Karelia. Methods. Samples of soil, vegetation, surface water, sediments and biota (fish) were taken. In total, 300 samples were collected. The analysis of the material was carried out using epithermal instrumental neutron activation analysis (INAA), x-ray spectral analysis (XRF), and atomic absorption spectrometry (AAS) with "cold steam" and inductively coupled plasma spectrometry (ICP-MS). Concentration of 32 chemical elements in soil, birch leaves, sediments, water and biota (fish) was determined. Results. The distribution of macro- and microelements in soil and vegetation of these main cities of Karelia was determined. Geochemical profiles of distribution of elements in soils and vegetation were constructed. Concentration of heavy and toxic metals in the samples of water and sediments was close to the background values. High concentration of mercury in the muscles of predatory fish was found (CHg = 0.2÷0.3 mcg/kg). Conclusions. The levels of total accumulation of heavy and toxic metals in the soil of Petrozavodsk are classified as hazardous (Zc = 56), and soil pollution in Pitkyaranta, Sortavala and Suoyarvi is considered moderately dangerous (Zc = 15-31). A high degree of correlation between the concentration of elements in the soil and birch leaves was found. The water in lake Ladoga, lake Onega, and lake Suoyarvi in terms of the concentration of the elements presented in the article meets the Russian standards for drinking water.

This work presents the results of integrated micropaleontological and lithogeochemical analysis of Upper Oligocene continental deposits of the Turtas Formation from the Zyryanskaya-1 borehole (southwestern part of the Tyumen Region, Western Siberia). The predominance of freshwater planktonic diatoms at the subordinate significance of benthic species, as well as the presence of gemmuloscleres of sponges, indicates the coastal sedimentation conditions in a freshwater basin varying in depth from 3 to 50 m. The studied palynocomplex is similar to the spore-and-pollen spectra of the Turtas Formation of the Lower Ob Region, but differs from palynocomplexes of the same formation spread over the southern regions of Western Siberia in a low amount of Taxodiaceae/Cupressaceae and Betulaceae pollen, as well as the absence of Fagaceae pollen and Pseudokomewuia freshwater dinocysts. The revealed differences can be explained both by facies features and by variations in the volume of the Turtas Formation in the currently known localities. The data on the microelemental composition of samples, as well as geochemical and petrogeochemical modules, indicate that the accumulation of the Turtas Formation occurred in the coastal areas of a low-mineralized basin under relatively warm humid climatic conditions.

The Doldrums Megatransform System (~7–8°N, Mid-Atlantic Ridge) shows a complex architecture including four intra-transform ridge segments bounded by five active transform faults. Lower crustal rocks are exposed along the Doldrums and Vernadsky transform walls that bound the northernmost intra-transform ridge segment. The recovered gabbros are characterized by variably evolved chemical compositions, ranging from olivine gabbros to gabbronorites and oxide gabbros, and lack the most primitive gabbroic endmembers (troctolites, dunites). Notably, the numerous recovered gabbronorites show up to 20 vol. % of coarse-grained orthopyroxene. Although covariations in mineral and bulk-rock chemical compositions of the olivine and oxide gabbros define trends of crystallization from a common parental melt, the gabbronorites show elevated light over heavy rare earth elements (LREE/HREE) ratios in both bulk-rock and mineral compositions. These features are not consistent with a petrological evolution driven solely by fractional crystallization, which cannot produce the preferential enrichments in highly incompatible elements documented in the orthopyroxene-bearing lithologies. We suggest that gabbronorites crystallized from evolved melts percolating and partly assimilating a pre-existing olivine gabbro matrix. Saturation in orthopyroxene and selective enrichments in LREE relative to M-HREE are both triggered by an increase in assimilated crystal mass, which ranges from negligible in the oxide-gabbros to abundant in the gabbronorites. This melt–rock reaction process has been related to lateral melt migration beneath ridge-transform intersections, where variably evolved melts injected from the peripheral parts of the melting region towards the transform zone may interact with a gabbroic crystal mush to form abundant oxide-bearing gabbronoritic associations.

Purpose. We studied accumulation of mercury in the main natural and urban environments of Karelia, Northwest Russia, and assessed potential sources of mercury in a human body. Methods. A total of 200 samples of soil, vegetation, water, surface water, sediments and fish were collected. An analysis of samples was carried out by cold steam atomic absorption method. Diagrams of mercury distribution in soil, birch leaves and lichens were created. Data on fish consumption by the population of Petrozavodsk and Medvezhyegorsk are studied. The concentration of mercury in fish muscles most consumed in Petrozavodsk and Medvezhyegorsk was estimated. Results. Levels of mercury accumulation in soil and vegetation in the studied settings do not exceed the standards adopted in Russia. The same was observed for mercury concentration in water and sediments. Calculation of mercury intake showed that there is a 3-fold difference in the annual intake of mercury in the human body due to differences in the structure of fish consumption in these cities. Summary. External factors do not lead to higher concentrations of mercury in the main natural and urban environments of Karelia. High concentration of mercury in biological samples of pregnant women in the Medvezhyegorsk district is due to the peculiarities of the diet of the local population - the predominance in the diet of freshwater fish (pike, perch, pike perch) caught directly in the Onega lake.

Palaeoproterozoic amphibole-biotite orthogneisses with a protolith age of ~ 1840 Ma and Neoproterozoic muscovite-chlorite orthogneisses with an estimated protolith age of ~ 790 Ma have been identified in the structure of the Zheltau terrane (Southern Kazakhstan; west Central Asian Orogenic belt). In addition, metasedimentary complexes represented by prevailing garnet-mica schists and subordinate muscovite-chlorite schists with obtained detrital zircon ages in the range of 604 - 2819 Ma (with two peaks at ~ 991 Ma and ~ 1082 Ma) also comprise the Zheltau terrane. In accordance with the Sm-Nd whole-rock isotopic compositions, the protolith of the observed Palaeoproterozoic orthogneisses formed as a result of a mixing of the Neoarchean crustal source with a juvenile source, whereas the formation of the Neoproterozoic orthogneisses protolith may have been related to the melting of Palaeoproterozoic crustal material. In turn, Late Mesoproterozoic – Early Neoproterozoic granitoids or felsic volcanic rocks, which formed as a result of the melting of Palaeoproterozoic continental crust, are considered as possible sources for the studied detrital zircons obtained from the schists. The terrigenous protolith of the schists from the Zheltau terrane accumulated in the range of ~ 600 to ~ 490 Ma, corresponding to the Ediacaran-Cambrian. Subduction processes in the Early Palaeozoic led to the burial of different horizons of the Zheltau terrane continental crust to significant depths; some of the complexes experienced high-pressure metamorphism at P 15 – 18 kbar; T 750 – 850 °C (high-pressure granulites), whereas most of the rocks were evidently metamorphosed at maximum amphibolite facies and avoided high-pressure re-equilibration. The spatial proximity of the studied metamagmatic and metasedimentary crustal complexes and similar metamorphic changes during the latest stages of retrogression imply their possible mutual exhumation from different levels during the period between 490 and 470 Ma and their following juxtaposition as a package of tectonic slices.

Spinel-bearing ultramafic rocks, metamorphosed in high-pressure conditions, are described from the metamorphic complexes of the western part of the Central Asian Orogenic Belt (CAOB) in the Chu-Yili region in Southern Kazakhstan. They comprise small bodies of magnetite-bearing serpentinites, Cr-spinel-bearing serpentinized and amphibolitized dunites and peridotites enclosed by strongly retrogressed kyanite-bearing paragneisses. Apart from serpentinization, the ultramafic rocks were also overprinted by later rodingitization expressed in the development of the index-minerals hydrogrossular, prehnite and vuagnatite. Cr-spinel-bearing peridotites are characterized by extensive development of symplectitic and coronitic microtextures, which are interpreted to have been formed after garnet breakdown during decompression (i.e. exhumation). Calculated pressure (P) and temperature (T) obtained by phase diagram modeling and conventional geothermobarometry for the symplectites were P 11.5–14.5 kbar for a wide temperature range of T 600–850 °C, which followed the transition from garnet to spinel peridotite. Major and trace element whole-rock geochemical characteristics of the spinel-bearing ultramafic rocks as well as their structurally close relations indicate their mutual origin as parts of an oceanic cumulate complex of an arc-basin system. The protoliths were probably plagioclase-bearing (thus shallow, crustal) ultramafic rocks and troctolites, subducted to eclogite facies conditions and then exhumed along with other metamorphic complexes of the Zheltau massif. These spinel-bearing ultramafic rocks could be classified as crustal formations in accordance with the inferred depths of their origin (

The paper analyses the problem of how health preservation is perceived by teenagers, adolescents and youths, demonstrating the need for research of students’ perceptions of individual health and its preservation at different stages of life. An empirical study conducted with 522 students of the Moscow Polytechnic University (3 age groups, average age 17, 19 and 21 years) used a custom questionnaire aimed at examining their perceptions regarding the greatest value of the health factor at different stages of life from infancy to elderly age. The study revealed an unfortunate downward trend of individual health value with respect to the age when systematic health problems appear. Some gender differences in attitude towards individual health were discovered; for instance, women place a higher value on it for every stage of life and attach greater importance to it in early ontogeny. Men were found to overestimate the age associated with the onset of system health issues. The paper shows the possibilities for practical application of obtained data.

Data on the mercury concentration in freshwater and marine fish and seafood on the territory of Russia are presented. The level and pattern of the fish and seafood consumption in various regions of Russia are found from the analysis of open statistics. Regions with the maximum and minimum consumption of fish products are established. Mercury intake from these products in a human organism is calculated. It is shown that at the current level and pattern of the diet in Russia fish cannot be a source of high mercury concentrations in a human organism.

World Health Organization (WHO), in cooperation with the Consortium to Perform Human Biomonitoring on a European Scale (COPHES), has developed a standardized methodology for human biomonitoring (HBM) surveys in maternities in order to assess prenatal exposure to mercury. To test this standard methodology and adapt it to Russian settings, a cross-sectional HBM survey involving 120 parturient women was conducted in six maternities of the Moscow Region. Levels of total mercury in maternal hair (geometric mean: 0.21 μg/g, 95th percentile: 0.54 μg/g), cord blood (0.89 μg/L and 2.38 μg/L, respectively) and maternal urine (0.27 μg/L and 0.94 μg/L) in this population were similar to those in other European countries with relatively low fish consumption. Consumption of all types of fish at least once per week during the third trimester of pregnancy compared to fish consumption less than once per month was associated with the increase of geometric mean level of total mercury: in hair by 31% (95% confidence interval: 4%, 66%) higher, in cord blood--by 38% (9%, 74%) and in maternal urine--by 36% (2%, 81%). No biomarker values exceeded levels recommended by WHO or national agencies in the USA and Germany. However; at the population level, adverse effects of prenatal exposures to mercury can still be substantial.

A relationship between the level of the body adaptation resources as an indicator of human individual health and smoking was established by means of examining 304 first-year university students. A trend for the number of smoking young men to increase with an increase in their adaptation potential is interpreted from the point of view of the social adaptation of first-year students in group activity.

The mechanism underlying the process of coordination of tracking movements of humans in the virtual space of an executive action with a change in the semantic organization of a motor task was investigated. The specific features of the distribution of the components of the velocity vector of tracking movements in the “target” (related to the aim of the motor task) system of coordinates allow the results of a compromise of the joint functioning of parallel motor programs to be interpreted from the point of view of their coordinated adaptation to the geometry of the outer space and the specifics of the task solved.

To approach the applied aspects of support to operator interacting with the aerospace technical systems, the authors are working on the problems of structuring the motor programs and deformation caused to them by semantic stressful agents. Possibility for varying the composition of locomotion programs to ensure success of a general motor task had been experimentally demonstrated. Data obtained are viewed from the standpoint of revision of the motor image in the psychic control system.

System mechanisms, that underlied motor activity coordinations were investigated on the model of biological oscillator. It has been shown how the value of phase resettings induced by single stimuli sequences depends on the stimulation location in the cycle. The time of reaction to the stimulus has been determined as the function of stimulus location. In addition, the character of transitional process, after which the parameters of initial rhythmic activity completely become normal, has been determined. The data obtained have been interpreted for the model of temporal motor control, which was suggested by A. Wing and A. Kristofferson.

Modeling of wave motion of human body's multi-segment biomechanical system by examination of forced transverse oscillations of one-dimensional bar system with distributed parameters is performed in javelin throwing. Energy flow value under different changes of model parameters is investigated. The experimental data showing wave front motion and transformation of spectral density of oscillations from segment to segment of the thrower's body are discussed. Share of the energy transferred along the body's segments in the total energy of javelin release is 70-72 per cent according to theoretical estimates for concrete model parameters, and 63-75 per cent according to the experimental data for 8 attempts.