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In this paper the development of structure and circuit solution for a bidirectional wireless power transmission system is presented, based on current fed push-pull inverter. Existing solutions are analyzed, as well their structures and characteristics. The principle of operation of the developed circuit solution is described in receiving/transmitting mode, an electrical principal circuit is given with respective ratios calculated. The SPICE modeling of the system was performed, and the theoretically calculated dependency of energy transmission efficiency from the transmitted power was obtained. The developed structure includes a step-up DC-DC converter, which enables to obtain the output voltage of the system, active in receiving mode, being equal or higher than the voltage of the power supply of energy-transmitting system. Therefore, the proposed bidirectional wireless power transmitting system can be utilized within a swarm robotic system with unified robots, having identical power supply batteries. Practical application of the proposed solution is relevant for energy transmission among autonomous robots, energy transmission from power supply source to robot and in reverse direction.

In this paper an approach is presented, enabling to solve the problem of local navigation of mobile robotic platforms (MRP), based on utilization of wireless networks with mesh topology. Establishment of wireless networks was ensured, based on the set of radio modules, mounted on unmanned aerial vehicles (UAV), comprising a swarm. This paper presents a developed algorithm for establishment of such wireless networks, aided by LoRa-technology, as well as an algorithm for MRP localization, based on analysis of signal level, where the incoming signals are fed from MRP group radio modules to radio modules of wireless data transfer network. An algorithmic model is given for task distribution among UAV and to implement navigational capabilities of MRP swarm. In some experiments descending dependencies of absolute error value, pertinent to MRP, from the number of UAV in action were revealed, as well as of averaged deflection value of MRP positions in motion along their paths from the number of UAV in action. Thereby the averaged value of MRP localization error, depending on the number of UAV in action, was from 8.14 to 17.13 m, and the averaged value of MRP position deflection – from 16.38 to 57.12 m, respectively.

The article is devoted to the rounded vowels in the Anatri dialect of Chuvash which correspond to the unrounded «y» and «i» in Standard Chuvash. The author found that in some cases these vowels are reflexes of labial vowels оf Proto-Turkic language. In other cases, labial «y» and «i» are the result of secondary labialization.

Oil wastes produced in large amounts in the processes of oil extraction, refining, and transportation are of great environmental concern because of their mutagenicity, toxicity, high fire hazardousness, and hydrophobicity. About 40% of these wastes contain radionuclides; however, the effects of oil products and radionuclides on soil microorganisms are frequently studied separately. The effects on various microbial parameters of raw waste containing 575 g of total petroleum hydrocarbons (TPH) kg−1 waste, 4.4 of 226Ra, 2.8 of 232Th, and 1.3 kBq kg−1 of 40K and its treated variant (1.6 g kg−1 of TPH, 7.9 of 226Ra, 3.9 of 232Th, and 183 kBq kg−1 of 40K) were examined in a leaching column experiment to separate the effects of hydrocarbons from those of radioactive elements. The raw waste sample (H) was collected from tanks during cleaning and maintenance, and a treated waste sample (R) was obtained from equipment for oil waste treatment. Thermal steam treatment is used in the production yard to reduce the oil content. The disposal of H waste samples on the soil surface led to an increase in the TPH content in soil: it became 3.5, 2.8, and 2.2 times higher in the upper (0–20 cm), middle (20–40 cm), and lower (40–60cm) layers, respectively. Activity concentrations of 226Ra and 232Th increased in soil sampled from both H- and R- columns in comparison to their concentrations in control soil. The activity concentrations of these two elements in samples taken from the upper and middle layers were much higher for the R-column compared to the H-column, despite the fact that the amount of waste added to the columns was equalized with respect to the activity concentrations of radionuclides. The H waste containing both TPH and radionuclides affected the functioning of the soil microbial community, and the effect was more pronounced in the upper layer of the column. Metabolic quotient and cellulase activity were the most sensitive microbial parameters as their levels were changed 5–1.4 times in comparison to control ones. Changes in soil functional characteristics caused by the treated waste containing mainly radionuclides were not observed. PCR-SSCP (polymerase chain reaction – single strand conformation polymorphism) analysis followed by MDS (metric multidimensional scaling) and clustering analysis revealed that the shifts in microbial community structure were affected by both hydrocarbons and radioactivity. Thus, molecular methods permitted to reveal the effects on soil microbial community not only from hydrocarbons, which significantly altered functional characteristics of soil microbiome, but also from radioactive elements.

Type 1 diabetes (T1D) is related to the autoimmune destruction of β-cells, leading to their almost complete absence in patients with longstanding T1D. However, endogenous insulin secretion persists in such patients as evidenced by the measurement of plasma C-peptide. Recently, a low level of insulin has been found in non-β islet cells of patients with longstanding T1D, indicating that other islet cell types may contribute to persistent insulin secretion. The present study aimed to test the ability of various antibodies to detect insulin in insulin-deficient islets of T1D patients. Pancreatic autopsies from two children with recent-onset T1D, two adults with longstanding T1D, and three control subjects were examined using double immunofluorescent labeling with antibodies to insulin, glucagon and somatostatin. Immunoreactivity to insulin in glucagon+ cells of insulin-deficient islets was revealed using polyclonal antibodies and monoclonal antibodies simultaneously recognizing insulin and proinsulin. Along with this, immunoreactivity to insulin was observed in the majority of glucagon+ cells of insulin-containing islets of control subjects and children with recent-onset T1D. These results suggest that islet α-cells may contain insulin and/or other insulin-like proteins (proinsulin, C-peptide). Future studies are needed to evaluate the role of α-cells in insulin secretion and diabetes pathogenesis. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study aimed at obtaining new experimental data on the regularities of evaporation of droplets of polyfractional composition in a high-enthalpy gas flow. This study considers the features of heating and subsequent vaporization of water droplets with diameters of 5...100 μm in an air flow with initial temperature up to ∼600 K and velocity up to ∼100 m/s at subcritical Weber numbers. The description of the laboratory setup equipped with laser-shadow means of diagnostics of two-phase flows and the proposed methodology of processing of the registered parameters are presented. On the basis of the conducted experiments, quantitative indicators of the intensity of the process of evaporation of polydisperse water droplets in the air flow are determined. The database of experimental data on the motion and evaporation of water droplets in the air flow, which has been developed according to the available literature sources, has been supplemented with new results, which makes it possible to clarify the corresponding physical and mathematical models. The results obtained can be used in planning and conducting subsequent studies. [ABSTRACT FROM AUTHOR]

We have shown how the kinetic equation for the velocity distribution function of an ensemble of turbulent velocities can be rigorously obtained from the Boltzmann kinetic equation with the classical collision integral. Compared to the Boltzmann equation on the left-hand side, the resulting kinetic equation of turbulence contains ten additional terms. Also, instead of the frequency of molecular collisions ν coll , the collision integral in the kinetic equation of turbulence includes the collision frequency ν t p , which is significantly less than the frequency of molecular collisions. There are two key steps we have undertaken in obtaining the kinetic equation of turbulence. First, we used the invariance of the collision integral of the Boltzmann equation with respect to the Gaussian transformations. Second, we introduced the idea of fragmentation of turbulent flows into turbulent fluid quasiparticles. Each such quasiparticle is described by an equilibrium distribution of molecular velocities with fluctuating mean velocity. Also, each quasiparticle is characterized by its size, which is in the range of length scales larger than the mean free path of molecules λ and less than the typical length of spatial variation in the turbulence distribution function. [ABSTRACT FROM AUTHOR]

The Syum-Keu massif is the northernmost ophiolite complex of the Ural mobile belt. It differs from other massifs of the Polar Urals due to the prominent distribution of lherzolites in the upper mantle section. This feature aligns it more closely to some massifs in the southern part of the belt (Kraka). Thus, a comparison of the ultramafic rock compositions in these massifs is highly relevant. Thus, comparing the compositions of ultramafic rocks from these massifs is highly relevant and is one of the primary objectives of this study. Our second objective is to study the microstructural features of ultramafic rocks from the upper mantle, as they can indicate modes of subsolidus processes that played a key role in the formation of this massif. Our study utilizes optical microscopy, assessments of bulk rock composition using X-ray fluorescence and ICP-MS, as well as mineralogical methods, such as scanning electron microscopy with energy dispersive spectroscopy and electron backscattered diffraction, for the microstructural analysis of peridotites. In addition to ultramafic rocks from the upper mantle section, the composition and mineralogy of mafic rocks from the crustal section were studied. The microstructural analysis of ultramafic rocks indicates their two-stage evolution. The first is associated with plastic flow under the upper mantle conditions dominated by the olivine slip along the {0kl}[100] system, while the second reflects formation in the lower crust, with lower-temperature deformation along the {110}[001] slip system. Comparing the mineralogy of the Syum-Keu peridotites to lherzolite massifs in the Southern Urals reveals a significant difference in accessory Cr-spinel composition; the former show elevated iron content (Fe trend), indicating intense crustal metamorphism. Similarly, amphiboles in Syum-Keu ultramafic rocks exhibit a significant crustal (metamorphic) component, while the same minerals in the Kraka massif suggest a mantle (magmatic) origin. Mafic rocks in the Syum-Keu massif also typically display a high degree of metamorphism. The obtained results generally corroborate prior findings on a longer evolution of the upper mantle ultramafic rocks of the Syum-Keu massif compared to those of the Kraka massif. Our results are also consistent with the suprasubduction nature of these ultramafic rocks. Our findings can be utilized in further studies of the microstructure and composition of ophiolites from the Polar Urals to provide a more detailed characterization of the partial melting conditions of the mantle source, the plastic flow of peridotites, and their interaction with melts and fluids. [ABSTRACT FROM AUTHOR]

Specific spatiotemporal patterns of the normal glial differentiation during human brain development have not been thoroughly studied. Immunomorphological studies on postmortem material have remained a basic method for human neurodevelopmental studies so far. The main problem for the immunohistochemical research of astrogliogenesis is that now there are no universal astrocyte markers, that characterize the whole mature astrocyte population or precursors at each stage of development. To define the general course of astrogliogenesis in the developing human cortex, 25 fetal autopsy samples at the stages from eight postconceptional weeks to birth were collected for the immunomorphological analysis. Spatiotemporal immunoreactivity patterns with the panel of markers (ALDH1L1, GFAP, S100, SOX9, and Olig-2), related to glial differentiation were described and compared. The early S100 + cell population of ventral origin was described as well. This S100 + cell distribution deviated from the SOX9-immunoreactivity pattern and was similar to the Olig-2 one. In the given material the dorsal gliogenic wave was characterized by ALDH1L1-, GFAP-, and S100-immunoreactivity manifestation in the dorsal proliferative niche at the end of the early fetal period. The time point of dorsal astrogliogenesis was agreed upon not later than the 17 GW stage. ALDH1L1 + , GFAP + , S100 + , and SOX9 + cell expansion patterns from the ventricular and subventricular zones to the intermediate zone, subplate, and cortical plate were described at the end of early fetal, middle, and late fetal periods. The ALDH1L1-, GFAP-, and S100-immunoreactivity patterns were shown to be not completely identical. [ABSTRACT FROM AUTHOR]