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[Display omitted] • The igneous rocks belong to high-K calc-alkaline to shoshonitic series intrusions. • U-Pb zircon dating indicated a long-lasting (from ca. 325 Ma to ca. 302 Ma) magma emplacement. • The pluton emplacement took place in the extensional post-collisional setting. • Ancient xenocrystic zircons (dated at ca. 1.9 Ga) suggest a Paleoproterozoic basement. • The plutons are accompanied by oxidized-type skarn-porphyry W-Mo-Cu-Au mineralization. The Kensu and Dzholkolot multiphase intrusions are situated in the eastern part of the "Main Structural Line of Tien Shan", or the "Nikolaev Line". The plutons comprise mafic to intermediate (monzogabbro, monzonite, syenite, quartz syenite) and silicic (quartz monzonite, monzogranite, and leucogranite-alaskite) members, together with the interim (camptonite) and final monzodiorite-porphyry dikes. Geochemical signatures of the igneous rocks correspond to high-K calc-alkaline to shoshonitic series intrusions, with a strong A-type affinity, emplaced in post-collisional setting. Magmatic evolution included a generation of shoshonitic magma by a low-degree partial melting of the metasomatically-enriched upper mantle, followed by amphibole fractionation in a deep (lower crustal?) magma chamber. This was followed by a generation of mantle-induced granitic magmas in a crustal protolith, with possible mixing/mingling of various magmas. The rocks crystallized at shallow levels, in an oxidized environment, under decreasing pressure and temperature toward the younger (granitic) intrusion phases. Isotopic U-Pb (LA-ICP-MS) zircon dating of the igneous rocks indicates their Late Carboniferous age (ca. 325–302 Ma). The magma emplacement included a number of intrusion phases from monzogabbro (321 ± 4 Ma), monzonite (319 ± 4 Ma), and camptonite (306 ± 4 Ma), to quartz syenite (305.5 ± 2 Ma to 302 ± 3.7 Ma), quartz monzonite (305 ± 3 Ma) and subsequent granitic phases. Although the ages identified correspond to those of the subduction-related magmatism in the western part of the Middle Tien Shan, geochemical characteristics of the rocks supporting rather post-collisional setting of the plutons are in agreement with a "scissor-like" closure of the Turkestan paleoocean, starting from the east. Zircon xenocrysts dated at ca. 1.9 Ga suggest the presence of an underlying old continental crust. The skarn-porphyry W-Mo(−Cu-Au) mineralization complements the group of similar deposits associated with high-K calc-alkaline to shoshonitic series intrusions in the Middle Tien Shan and globally. The high endowment in W and Mo can be related to the fertilization of subduction-modified subcontinental lithospheric mantle in these metals, together with more common fertilization in Cu and Au, with its subsequent involvement in the magma generation in post-collisional setting. The endowment in W and Mo can also reflect a greater involvement of an ancient continental crust as the magma source(s). The oxidized paragenesis of hydrothermal alteration assemblages and mineralization corresponds to the respective affinities of the igneous rocks. [ABSTRACT FROM AUTHOR]

The paper compares the accuracy of reconstruction using different wavelets, and the authors also use fast and discrete Fourier transforms together to calculate the forward and inverse continuous wavelet transform in the frequency domain. Due to the use of calculations in the frequency domain, it becomes possible to perform decomposition, reconstruction, image filtering, and other transformations with high performance and precision. For multiscale signal analysis, a wavelet with a rectangular amplitude-frequency response has been constructed, which allows for an increase in the accuracy of decomposition and reconstruction compared to the Mallat algorithm presented in Matlab computer mathematics. At the same time, the time of multiscale analysis is reduced several times compared to the Mallat algorithm. [ABSTRACT FROM AUTHOR]

Conceptual model of the crustal structure of the Mendeleev Rise and adjacent area. [Display omitted] • SDR-like seismic units are typical for Alpha-Mendeleev Rise (AMR) and adjoining basins. • AMR formed as a double-sided volcanic passive continental on continental crust. • AMR formed synchronously with the adjoining basins. Data collected by several expeditions to the Arctic Ocean have yielded a seismic stratigraphic framework and basin fill history for the Alpha-Mendeleev Rise (AMR) and adjacent Podvodnikov, Makarov, North Chukchi, Toll, Mendeleev, Nautilus and Stefansson basins. The AMR comprises a double-sided volcanic passive margin formed in Aptian-Albian time. The North Chukchi, Podvodnikov, Toll, Mendeleev, Nautilus, and Stefansson basins formed synchronously with the Alpha-Mendeleev Rise as failed micro-oceanic basins. Their formation started with rifting and volcanism at ∼ 125 Ma and ended at 100–90 Ma. Ages are constrained by new isotope magmatic rock ages. The region now comprising the Amerasia Basin was in an intraplate tectonic setting during Aptian-Albian times. On the Mendeleev Rise seismic units interpreted as seaward-dipping reflectors (SDRs) form wedges separated by highs. We propose an axial line along the Mendeleev Rise that separates probable half-grabens of different polarity. On the western slope of the Rise, all bright reflections have westward dips, while on the eastern slope they have eastward dips. SDR-like seismic units are common within the adjacent basins as well. Gravity/magnetic crustal modelling for two regional seismic lines demonstrate that the Mendeleev Rise and adjacent basins are associated with stretched continental crust. [ABSTRACT FROM AUTHOR]

In today's dynamic, rapidly changing world, a bachelor's engineer needs to have creative thinking skills in order to be successful in their professional activities. A future graduate must learn to see the problem as a whole, and not in the context of one area of science or technology. This causes the education system to develop and implement innovative forms of engineering personnel training aimed at solving practice-oriented, research problems. The authors considered the issue of applying an educational model that combines natural sciences and engineering subjects into a single system in the process of teaching engineering bachelors. The issues of effective formation of critical thinking skills based on an integrative approach are analyzed. The results of experimental work convincingly prove that the majority of students studying on the basis of the author's methodology have achieved an average and high level of creative thinking skills. [ABSTRACT FROM AUTHOR]

The problem of improving the educational process of students of scientific, technical and natural science areas of training is one of the relevant aspects of modern pedagogical research. During training, it is necessary to apply new approaches, educational technologies and techniques in order to prepare graduates who are able to independently solve complex scientific, technical and engineering design tasks in the process of modern production. Programming is a universal tool for modeling objects and processes, as well as a powerful tool in developing the thinking of students of scientific, technical and natural science fields of training. The article discusses the issues of formation of programming skills of students based on the use of the Arduino platform. The professional standards are analyzed, the main contradictions of the existing system of training future bachelors in the field of radio electronics and control systems are revealed. The method of organizing effective programming training based on the use of the Arduino platform is presented. The criteria and indicators of the levels of competence formation are given. The results of an experiment on the implementation of the described methodology of teaching programming on the basis of the I.N. Ulyanov Chuvash State University are shown. Using the chi-square criterion, statistical processing of the results of a pedagogical experiment was performed, which convincingly proves that when using the Arduino platform, most students have reached high and advanced levels of programming skills formation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Serious side effects and post-infection sequelae have been reported in SARS-CoV-2-infected patients after acute disease phase. • Long-COVID patient characteristics and symptoms were compared to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). • The onset, progression, and symptom profile of long-COVID patients have considerable overlap with ME/CFS. • Longitudinal monitoring of COVID-19 patients is warranted to understand the virus long-term effects. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) disease (COVID-19) triggers the development of numerous pathologies and infection-linked complications and exacerbates existing pathologies in nearly all body systems. Aside from the primarily targeted respiratory organs, adverse SARS-CoV-2 effects were observed in nervous, cardiovascular, gastrointestinal/metabolic, immune, and other systems in COVID-19 survivors. Long-term effects of this viral infection have been recently observed and represent distressing sequelae recognised by the World Health Organisation (WHO) as a distinct clinical entity defined as post-COVID-19 condition. Considering the pandemic is still ongoing, more time is required to confirm post COVID-19 condition diagnosis in the COVID-19 infected cohorts, although many reported post COVID-19 symptoms overlap with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). In this study, COVID-19 clinical presentation and associated post-infection sequelae (post-COVID-19 condition) were reviewed and compared with ME/CFS symptomatology. The onset, progression, and symptom profile of post COVID-19 condition patients have considerable overlap with ME/CFS. Considering the large scope and range of pro-inflammatory effects of this virus, it is reasonable to expect development of post COVID-19 clinical complications in a proportion of the affected population. There are reports of a later debilitating syndrome onset three months post COVID-19 infection (often described as long-COVID-19), marked by the presence of fatigue, headache, cognitive dysfunction, post-exertional malaise, orthostatic intolerance, and dyspnoea. Acute inflammation, oxidative stress, and increased levels of interleukin-6 (IL-6) and tumor necrosis factor α (TNFα), have been reported in SARS-CoV-2 infected patients. Longitudinal monitoring of post COVID-19 patients is warranted to understand the long-term effects of SARS-CoV-2 infection and the pathomechanism of post COVID-19 condition. [ABSTRACT FROM AUTHOR]

Crystal structure of rare-earth LaCoO 3 cobalt oxide subjected to high energy mechanical activation has been studied. In the temperature range of 300–800 K, the electrical conductivity and Seebeck coefficient were measured. Thermal conductivity was measured at 300–480 K. Comparative analysis of thermoelectric properties of the samples prepared by standard solid-state reaction and using high-energy mechanical activation was carried out. It was found that the experimental X-ray diffraction patterns are best described within the model that allows the coexistence of two domains in samples with the same crystal symmetry, but different lattice a and c parameters. The percentage ratio of these domains in the samples depends significantly on the size of the initial particles in the solid-state synthesis reaction and the annealing temperature. Mechanical activation and increase of synthesis temperature result in change of Seebeck coefficient sign and significant decrease of electrical resistivity. The Seebeck coefficient of non-activated samples takes positive values over the entire temperature range and decreases monotonically with increasing temperature, in contrast to mechanically activated samples exhibiting ambipolar behavior. [Display omitted] • A significant effect of mechanical activation on the thermoelectric properties. • Coexistence of two crystal domains in LaCoO 3 samples was found. • Effect of morphology on the thermoelectric properties. [ABSTRACT FROM AUTHOR]

Despite the presence of body composition studies in Russia, there are no current reviews on this topic, and the results are relatively rarely published abroad. Our aim was to describe the history and current state of this research work, to list unresolved problems, and to outline possible developmental trends. For completeness, in the initial part of the review, traditional research areas indirectly related to body composition studies are considered, namely, the analysis of biological variation of anthropometric parameters and somatotyping. It can be seen that anthropometry and bioimpedance analysis (BIA) are mainly used to assess body composition in Russia. Other methods, such as double-energy X-ray absorptiometry (DXA), are utilized less often. The achievements include the common use of comprehensive anthropometry in anthropological studies, some advancements in clinical studies, approbation of potentially important methods such as the deuterium dilution method and three-dimensional laser-based photonic scanning, and ongoing mass population BIA measurements in health centers. Various bioimpedance instruments are manufactured, the local reference BIA body composition data are available, and a large updated BIA database is ready for international comparisons. Among major limitations of body composition research in Russia, one can note the lack of validation studies using reference methods, so that foreign regression formulas are used with the double indirect methods, such as anthropometry and BIA, despite the fact that their accuracy has not yet been checked in our population. Conventional reference body composition assessment methods, such as three- or four-component molecular-level models and whole-body in vivo neutron activation analysis, were not applied yet, despite the technical feasibility. In general, it can be argued that the body composition research in Russia follows the observed global trends. Along with the achievements, there are a number of unresolved methodological and organizational issues. Prospects for further research include validation studies, updating reference population body composition data, and establishing local cut-offs for malnutrition and disease risks. In our view, further development could be facilitated with the establishment of well-equipped Human Body Composition Units in major Russian research centers, such as Moscow State University, which could be assigned a coordinating and methodical role. [ABSTRACT FROM AUTHOR]

In this article, the results of measurements and calculations of the power flux density in the frequency range 670 MHz-766 MHz (46th and 57th television channels) of digital broadcasting of the DVBT2 standard were presented. Experimental data on the power flux density were obtained by the selective electromagnetic field meters NARDA SRM-3000 with an isotropic antenna. The radiating system consists of 16 panel antennas (four-storey panel antennas) with a circular radiation pattern in the horizontal plane. Calculations were carried out in the ПК АЭМО (Software package for electromagnetic environment analysis) and MMANA programs. The data obtained were compared with the permissible exposure limit (PEL) of energy flux density (EFD) set by health and safety rules and standards (2.1.8/2.2.4.1383-03), which operate on the territory of Russia. The values obtained are significantly less than the acceptable levels. In the USA, Japan, European countries, Canada, China, and the PEL of energy flux density in the frequency range 300 MHz - 300 GHz are higher than in Russia. [ABSTRACT FROM AUTHOR]

The Laws of Ohm (1826) and Kirchhoff's laws (1847) are the basis for the theory of electric circuits. Using them when calculating electrical circuits, we need to create and solve a system of equations for circuit currents and nodal voltages. Kirchhoff's Theorem (1847) on finding currents of branches does not require the compilation and solution of this system of equations. Belov G. A. and Zakharov V. G. (2003) re-proved the Kirchhoff's Theorem (1847) and supplemented it with eight rules for calculating electric circuits. With the help of these rules, the currents of branches and nodal voltages are formed from a loop or nodal determinant and an electric circuit. At the same time, duplicate operations occur in the process of forming expressions of currents and voltages according to these rules. In this paper, we prove the theorems of the Fast Kirchhoff method about a complete and truncated tree, about a unique branch and loop, about common branches and loops, as well as the formulas of the Fast Kirchhoff method for generating currents of branches and nodal voltages. In the Fast Kirchhoff method, when calculating an electric circuit, there are no duplicate operations when generating currents of branches and node voltages, and this reduces the calculation time. [ABSTRACT FROM AUTHOR]

The tectonic settings and petrogenesis of Neoproterozoic gabbroic rocks are critical to understand the formation and evolution of the Arabian-Nubian accretionary orogen. We present the whole-rock chemistry and amphibole chemistry of the Gattar gabbro in the northern Eastern Desert of Egypt to better understand the formation of this part of the orogen. The Gattar gabbro is composed of variable proportions of amphibole and plagioclase, which imply the hydrous nature of its parent magma. Trace element patterns of the gabbro and the calculated liquids in equilibrium with its amphibole show enrichment in large ion lithophile elements relative to high field strength elements, which indicate that the Gattar magma formed above a subduction zone. The low abundances of high field strength element in the gabbro are consistent with a depleted mantle source similar to intra-oceanic island arc rocks. However, the high Nb/La ratio of the Gattar gabbro (0.46–10.71) is reminiscent to Nb-enriched mafic rocks from subduction settings. The amphibole chemistry suggests that the hydrous magma of the gabbro crystallized at temperature and pressure estimates of 930 °C and 8 kbar and under oxidizing conditions. The Gattar gabbro is affiliated with the Tonian-Cryogenian arc-related mafic gabbro, which is rarely recorded in this northernmost segment of the Arabian-Nubian orogen. In terms of comparison with the Ediacaran post-orogenic gabbros from the northern Eastern Desert, the Gattar gabbro shows lower concentrations of incompatible elements and Ti/V ratio. [ABSTRACT FROM AUTHOR]

A computational model of a wind tunnel (WT) with a special experimental rig has been developed directly for studying unsteady aerodynamic characteristics of a wing section with a helicopter blade profile. The model was constructed using CFD (Computational Fluid Dynamics) methods based on the URANS approach (Unsteady Reynolds Averaged Navier Strokes Equations). Therefore, the aerodynamic characteristics of the airfoil can be determined, taking into account influence of the WT walls such as walls perforation and various configurations of the experimental rig. Simulation of the flow around the wing section with the SC1095 airfoil in steady and unsteady settings is performed. The flow features in the working section of the WT and the experimental rig are analyzed. For a particular case, the calculation method was validated in a 2D formulation on the basis of available experimental data. The developed model can be used to refine the methods of processing experimental data, taking into account the individual characteristics of the WT and the experimental rig configuration. [ABSTRACT FROM AUTHOR]