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Objective: to determine the content of hormones, as well as some macro- and microelements in athletes-wrestlers outside the period of competition and active training.Materials and methods: the study involved 66 athletes-wrestlers and 107 students involved in sports professionally. The level of hormones and vitamin D was determined by the ELISA method. To analyze the content of macro- and microelements, the subjects were cut off a lock of hair from the back of the head in an amount of at least 0.1 g. The studies were carried out on an ICP-MS Agilent 7900 mass spectrometer.Results: levels of cortisol, TSH and T4 are higher, and levels of testosterone, T3 and vitamin D are lower in athletes compared to the control group. An increase in the content of sodium, calcium, potassium, magnesium, cobalt and a decrease in iodine were revealed in fighters from those who were not involved in sports professionally.Conclusion: the data obtained indicate an imbalance in the work of the body’s endocrine systems and impaired adaptation to stress. It is known that the determination of the hormonal status is used to assess the adaptation, the revealed changes in the indicators of vitamin D, macro- and microelements, allow the study of these indicators in order to prevent the syndrome of overtraining of athletes, to maintain and improve sports performance.

The article rises the current question about the need to develop a fire safety system of explosive objects (buildings, structures, buildings, industrial communications), as well as organizing assistance to local self-government bodies in the implementation of primary fire safety measures. The emphasis is placed on a fire prevention system, which includes a lightning protection system designed to protect the countryside and other objects of protection against atmospheric electricity discharges. Therefore, for proper design, control and maintenance of health, it is proposed to apply the original computer program. Which allows an express analysis of lightning protection parameters and make appropriate conclusions.

New approaches to increasing the efficiency of dislocation radiation in silicon, which is promising for use in optoelectronics, are considered. The anomalous temperature dependence of the luminescence of dislocation structures in silicon formed by implantation of Si+ ions and modified by ion doping with boron at different doses is discussed.

Synthesis and modification of gallium oxide as a wide-bandgap semiconductor is a topical task in the fields of power electronics, UV detectors, gas sensors, telecommunication. In the present work, the Ga2O3 films deposited on sapphire substrates by magnetron sputtering have been studied. The influence of deposition parameters and subsequent annealing on the structure and optical properties of the synthesized films is analyzed. Ion doping of magnetron-deposited films with silicon is carried out by the ion implantation method. It is shown by the Raman scattering and optical transmission spectroscopy that ion irradiation leads to the disordering of the crystal structure, but subsequent annealing results in a partial recovery of the structure. Hall-effect measurements for irradiated and then annealed films do not reveal the formation of a conducting layer. Apparently, this is due to the fact that the main contribution to the resistance is made by grain boundaries in the magnetron-deposited films.

Within the framework of the study, the process of evaporation of heated high-temperature oil products was studied, the results were used to determine the calculated values of the mass of vapors formed during the evaporation of spills of liquids heated above the design temperature. The result of the study was the development of a theoretical model based on the Stefan formula describing the rate of evaporation. This made it possible to establish that when heating high-temperature organic compounds form explosive vapor-air mixtures that pose a fire hazard.

To study the mechanism of a 9R-Si hexagonal phase formation upon ion irradiation of the SiO2/Si system, three types of experimental samples have been investigated by photoluminescence (PL) spectroscopy and transmission electron microscopy (TEM): SiO2/Si system irradiated by Kr+, silicon irradiated by Kr+ and silicon irradiated by (Kr+ + O+) ions. All the samples were annealed after irradiation. The first type sample shows the presence of the 9R-Si phase and PL band at ∼ 1240 nm; the third type sample shows the same PL band and twin defects; for the second type sample, the PL at 1240 nm is not detected. Based on the results, the role of mechanical stresses, radiation defects and oxygen in the formation of the hexagonal silicon phase is discussed.

The structure and optical properties of thin films of the chalcogenide semiconductor Ge2Sb2Te5, deposited by magnetron sputtering, was studied. A significant change in the topology and optical properties of the films is demonstrated with varying deposition conditions. It is shown that an increase in the deposition time leads to an increase in the surface roughness. Doping with nitrogen during deposition leads to a smoothing of the film surface, and also provides a strong change in the band structure and optical properties.

This article presents an algorithm and mathematical model for an identifying flaming combustion automated process by an unmanned aerial vehicle. A digital image processed by software filters serves as a resource about an accident and fire at oil and gas industry facilities. The algorithm deals with the aircraft height, the movement speed relative to the observation point, as well as relative to the surface background, the combustion source brightness and the investigated area flicker frequency. The generated mathematical model allows to detect a fire hazard by a drone without operator intervention.

The article presents an original solution to the problem of fire hazard indicators of oil products determining using molecular descriptors and artificial neural networks. The modelling of the forecasting process was carried out on the basis of a neural network training algorithm with a teacher and an error back propagation algorithm. The resulting model makes it possible to determine the fire hazard properties of substances in real time without time span and other costs.

Providing comprehensive security of the pipeline is the main task of monitoring linear facilities in the oil and gas industry. Proposed mathematical model is a part of an automated identification algorithm to determine the fire load type. The study identified four groups of combustible substances characteristic of oil and gas facilities: oil, refined products, liquefied petroleum gas and vegetation. There was a study of electromagnetic radiation of the optical range, recorded by an UAV’S digital camera for each type of substance. An algorithm for comparing the area color with a standard was proposed and implemented. The obtained mathematical correspondence allows identifying the fire color and the fire load type in conditions of different luminosity. The information on the flaming substance allows authorized rescue units to make operational decisions about the fire extinguishing method.

Recent advances in nanophotonics are due to the implication of new approaches to the photonic devices and components design, not only related to structural features, such as subwavelength periodic arrangements, but also new materials, e.g., phase-change materials like GeSbTe (GST) alloys. We consider recently proposed optical non-volatile GST memory cell with a GST diffraction grating instead of a continuous film placed on a silicon nitride waveguide. The grating allows diminishing the energy budget of an incident electromagnetic beam in case of an optically induced phase transition of GST due to excitation of the resonant guided mode in the grating. The excitation of this mode results in anomalous reflectance spectra of the waveguide-grating structure. Here, we present the reflection spectra of GST diffraction gratings on a silicon nitride waveguide calculated with the use of the matrix Riccati equation technique in the theory of multiple electromagnetic wave scattering in inhomogeneous media. We show how the reflection changes with variation of different parameters – grating period and height, incident wave polarization, and phase of the GST film.

The development of artificial intelligence systems is needed to solve many important challenges in neurobiology and neuroengineering for recreation of brain functions and efficient biorobotics. Here we propose a metal-oxide memristive device compatible with CMOS technology and suitable for hardware implementation of neuromorphic tasks. However, metal-oxide memristors have a significant drawback such as variation of resistive switching parameters due to the stochastic nature of filament formation in oxide material. In this work, we control the filament formation process by irradiation of oxide film surface with heavy ions. We have shown that the irradiation of oxide surface in the Au/SiO2/TiN memristive device with Xe+ ions (at energy of 5 keV) decreases the fluctuations of electroforming voltage, current-voltage characteristics during switching and increases the current ratio in the high/low resistance states. The ability to control internal parameters of the memristor can allow more efficiently using memristor as an element of neural networks and other neuromorphic circuits.

The regularities of ion synthesis of dislocation-related luminescence centers in silicon have been investigated. By varying the conditions of additional irradiation with boron ions, as well as the conditions of subsequent annealing, we obtain an increase in the luminescence intensity, as well as a shift of maximum of the temperature dependence towards higher temperatures. It was found for the first time that, for the highest used dose of boron ions (3·1017 cm-2) and additional heat treatment at 830 °C, it is possible to get the measurable luminescence at room temperature.

A simple and rapid method has been proposed for the determination of 1–25 μg/kg of diethylstilbestrol and β-adrenostimulator ractopamine in food by gas-liquid chromatography with an electron-capture detector. The extraction of the target components was performed by the QuEChERS method; the additional purification of the extract and preconcentration in the determination of diethylstilbestrol has been performed by dispersion liquid-liquid microextraction with tetrachloromethane. Recovery was 92–110% and preconcentration factor, 40. The time of analysis is 1.5–2 h; the relative standard deviation of the results of analysis does not exceed 10 %.

It has been demonstrated that the fluorometric test determination of gallium(III) can be performed with morin and lumogallion immobilized on thin-layer cellulose matrices. Test procedures have been developed for the determination of Ga(III) in the range 0.5–90 mg/L by the length of fluorescence zone on a test strip sealed into a polymer film (after its contact with the test solution) in the ranges 0.001–1 and 0.01–1 mg/L with the visual detection of the fluorescence of the indicator matrix with morin and lumogallion, respectively (after passing 100 and 20 mL of a test solution through it), and in the range 0.0001–0.1 mg/L by detecting the fluorescence with a portable fluorimeter.

Bipolar resistive switching in metal-insulator-semiconductor (MIS) capacitor-like structures with an inert Au top electrode and a Si3N4 insulator nanolayer (6 nm thick) has been observed. The effect of a highly doped n +-Si substrate and a SiO2 interlayer (2 nm) is revealed in the changes in the semiconductor space charge region and small-signal parameters of parallel and serial equivalent circuit models measured in the high- and low-resistive capacitor states, as well as under laser illumination. The increase in conductivity of the semiconductor capacitor plate significantly reduces the charging and discharging times of capacitor-like structures.

The response to electrical pulses of various parameters has been studied for the CMOS-compatible memristive nanostructures on the basis of silicon oxide demonstrating reproducible resistive switching. It is established that an increase in the amplitude or width of a single programming pulse is followed by the gradual decrease in the device resistivity. By applying periodic pulse sequences of different polarity it is possible to obtain both lower and higher resistance states. This adaptive behavior is analogous to synaptic plasticity and considered as one of the main conditions for the application of memristive devices in neuromorphic systems and synaptic electronics.

Using the envelope-function approximation, the single-particle states of electrons and holes in spherical GaN nanocrystals embedded in different amorphous dielectric matrices (SiO2, Al2O3, HfO2 and Si3N4) have been calculated. Ground state energies of electrons and holes in GaN nanocrystals are determined using the isotropic approximation of the k ⋅ p -Hamiltonian. All the ground state energies are found to increase with lowering the nanocrystal size and are proportional to the R−n, where R is the nanocrystal radius, n =1.5-1.9 for electrons and 1.7-2.0 for holes. The optical gap of GaN nanocrystals changes from 3.8 to 5 eV for the nanocrystal radius ranging from 3 to 1 nm.

For the memristive Au/SiOx/TiN/Ti structures produced by magnetron sputtering and demonstrating reproducible bipolar resistive switching, the dependence of resistive states on the dose of irradiation with H+ and Ne+ ions with energy of 150 keV has been established. It is shown that, under proton irradiation, the resistive switching is not deteriorated up to the dose of 1.1016 cm-2, and, in the case of Ne+ irradiation – up to the dose of 3.31015 cm-2 (equivalent by the ionization losses). As the Ne+ ions produce three orders of magnitude more elastic collisions than protons (for the same dose), the obtained results allow to predict the high radiation tolerance of the memristive structures to both ionization and displacement damage.