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In recent years, interest in the search for new potential molecular biomarkers to assess the effectiveness of the training process in elite sports, various pathologies caused by overload, and abuse of prohibited substances has reached an unprecedented level. MicroRNAs that regulate the processes of metabolism, differentiation, proliferation, and apoptosis of cells at the post-transcriptional level are the most valuable candidates for use in this regard. They are found in all biological fluids of the human body, are stable during long-term storage and resistant to changes in environmental conditions. It is known that changes in the miRNA expression profile are closely associated with physical activity, as well as with the administration of recombinant hormones, erythropoiesis-stimulating agents, and other substances and methods that improve sports performance, which are prohibited by the World Anti-Doping Agency (WADA).Objective: In this study, plasma samples from athletes involved in endurance sports (race walking) and non-athletic volunteers were analyzed using a hypoxia signaling pathway panel to identify hypoxia candidate markers.Materials and methods: Expression profiles of plasma circulating miRNAs were assessed by reverse transcription followed by real-time quantitative polymerase chain reaction (RT Q-PCR). The obtained data were subjected to statistical processing using the CFX Manager Software v3.1 program.Results: Three potential microRNA markers were identified: hsa-miR-210-3p, hsa-miR-320a and hsa-miR-935 (increased in athletes by 61.6 times, 51.8 and 41.0 times, respectively) — of physiological response to the training, load, which may be associated with the emergence of hypoxia during endurance training.Conclusion: We have obtained preliminary data on differences in the expression profiles of circulating miRNAs in healthy non-athletic volunteers and professional athletes in the out-of-competition period. In the future, it is planned to expand the sample of studied blood plasma samples and compare the expression profiles of circulating microRNAs in athletes in competition and out-of-competition periods, as well as to compare the expression profiles of circulating microRNAs during aerobic and anaerobic loads. In addition, it is of interest to analyze changes in the expression levels of circulating miRNAs when using hypoxia mimetics applied to improve sports performance.

TThe most important factor limiting sports performance is insufficient fluid intake by athletes and dehydration of the body, while a significant decrease in performance and sports endurance begins with a dehydration level of 2 % and above.Objective: to study the effectiveness and safety of rehydration of the body of athletes­skiers of children and youth using isotonic drinks «Izonok» and «Izonok+».Materials and methods: the main group (n = 12, 16.2 ± 1.4 years) took isotonic drinks for 30 days to compensate for fluid losses, the comparison group (n = 8, 15.7 ± 1.1 years) — drinking water. Bioimpedance body composition analysis was carried out on a KM-AR-01-”Diamant” device (RF, St.Petersburg), and central hemodynamic analysis was carried out on a «SIMONA 111» (LLC “Okulyus 2000”, RF). The content of secretory immunoglobulin A (sIgA) and lysozyme in saliva samples of athletes was carried out by the enzyme immunoassay on an ANTHOS 2010 analyzer (Austria). Statistical data processing was carried out using the Statistica 6.0 software package from Stat Soft @ Ink USA.Results: The intake of an isotonic drink is accompanied by the stimulation of the production of secretory immunoglobulin (sIgA) and lysozyme compared to the consumption of drinking water. The total volume of fluid and the volume of extracellular fluid tended to increase; the volume of intracellular fluid remained practically unchanged; the amount of total water when taking isotonic increased.Conclusion: The investigated isotonic drinks “Izonok” and “Izonok+” are effective sports drinks for maintaining optimal water-salt balance and local immunity

Striving to achieve the goals of the training process with the irrational use of physical activity can lead to a decrease in the adaptive and reserve capabilities of the athlete. The development of changes in the endocrine, cardiovascular and central nervous systems may result in the development of overtraining syndrome. There is no unified approach to the definition, diagnosis, treatment and prevention of overtraining syndrome in the literature up to the present day. The endocrine aspects of the development of the overtraining syndrome are not sufficiently studied. In particular, there is no clear understanding of the degree of involvement of various hormonal mechanisms in its pathogenesis and ideas about the possibilities of using hormone levels to diagnose this condition. The purpose of this publication is to summarize and systematize the available concepts regarding the endocrine aspects of the overtraining syndrome.

The first case of heart transplantation in the Far Eastern Federal District described. Transplantation of heart is executed in Republican hospital No. 1 - the National center of medicine (Yakutsk) on July 6, 2018. In our opinion, transplantation of heart is necessary and feasible in such regions as the Republic of Sakha (Yakutia) which have difficult and extreme climate and geography, remote settlements with population less than 1 million people.

In the article, an analysis provided of recent views on the overtraining syndrome by the data from local and foreign publications.The witness of the problem actuality is also an existence of controversial opinions and absence of clear definitions on properties of the condition. It has been revealed that the main role in pathogenesis of the overtraining syndrome do play the changes of cardiovascular, endocrine and central nervous systems. These changes are complicated and ambiguous, depend upon multiple factors, as the type of sport, specifics of exertion and loads, stage of pathophysiological process. Entraining effect of exertion, if incorrectly utilized, underestimation of current condition of a sportsman, might not lead to expected results. Moreover, non-rational application of exertion might lead to opposite effect, that is, to decrease adaptation potential and reserves, towards the edge of the condition as an overtraining syndrome, which shows phasic, progressing character, starting from fatigue and mild disorders, to persistent, rigidly reversible processes.Due to controversy, multiple stages and multifactorial of the overtraining syndrome, by now there is no unified approach to its definition, as no unified standards to its diagnostics, treatment and prevention.

Usual practice of a physician quite oftenly shows difficulties in differentiation of ischemic heart disease and so called “stressor” myocardium changes, occuring in persons participating in sports.

Early repolarization syndrome is common as ECG finding in sportsmen, and is usually due to vagotony, being usual in sportsmen. Sometimes the early repolarization might mimic pathological signs, e.g. acute myocardial infarction, that is a challenge for differential diagnostics, leading to false diagnostical decisions.

The Hamiltonian method is applied to the problem of tsunami generation caused by a propagating rupture front and deformation of the ocean floor. The method establishes an alternative framework for analyzing the tsunami generation process and produces analytical expressions for the power and directivity of tsunami radiation (in the far-field) for two illustrative cases, with constant and gradually varying speeds of rupture front propagation.

Two-dimensional vortex pairs are frequently observed in geophysical conditions, for example, in a shelf zone of the ocean near river mouths. The main aims of the work are to estimate the space scales of such vortex structures, to analyze possible scenarios of vortex pair motion and to give the qualitative classification of their trajectories. We discuss some features of the motion of strong localized vorticity concentrations in a given flow in the presence of boundaries. The analyses are made in the framework of a 2D point vortex mo-del with an open polygonal boundary. Estimations are made for the characteristic parameters of dipole vortex structures emitted from river mouths into the open ocean.

When controlling power objects operators face difficult situations of uncertainty and contradictions in instrument readings, release of displayed indications out of admissible value limit. The purpose of the paper consists in increasing reliability of automated power objects functioning applying the information system of operator activity support. The authors have developed the approach to operator activity information support in uncertainty. The matter of the approach consists in forming the models of changing phase coordinates and the control action by the object applied in the information support system. When indefiniteness occur during the object control the operator heuristic abilities are offered to be used to correct a certain part of a database, the model bases in cases when the operator manages to find quickly the way to solve the uncertainty accepted for practice. The approach developed reduces the operator mental load, increases his noise stability and capacity at occurrence of adverse psychological factors. The paper introduces the appropriateness of on-line correction of a database of information decision-support system.

Breast cancer is the most common cancer in women and one of the leading causes of death from cancer in Russia and most countries of the world. In countries with mammographic screening, there is a decrease in mortality from breast cancer. Introduction of mammographic image evaluation platforms into radiologist practice based on the work of artificial intelligence it allows not only to increase the coverage of the female population, but also to reduce the cost of screening, but it also increases the sensitivity and specificity of mammography as a method of breast cancer screening.The article presents the results of a study on the evaluation of mammographic images in women who have passed a preventive study using an artificial intelligence program.Within the framework of this project, mammographic images were analyzed using the service for viewing medical images “Celsus” in 8030 patients. The study assessed the age groups of 40-49 years, 50-59 years, 60 years and older. The average age of patients with suspected breast cancer was 54.8 years. Breast cancer was detected in 13 women (1.2 %), while the highest percentage of breast cancer was detected in the group with mammographic density D.

Modern trends in the aircraft development are associated with a significant increase in the level of its electrification. The emergence of new types of electricity consumers entails an increase in the power and number of consumers in the aircraft power supply system. At this stage of operation, direct control of the internal parameters (in particular, the parameters of reactive elements) of electricity consumers in the aircraft power supply system is not carried out. The aviation equipment control system is built taking into account the built-in system for monitoring the technical condition of the object. However, for greater efficiency, the built-in control can be supplemented with control capabilities through digital intelligent power distribution systems (local load control center). During the operation of aviation electrical equipment, the values of its parameters change relative to the nominal values. Deviations of equipment parameters from the nominal values should not exceed the specified values, which are determined by the operational technical documentation. Input impedances of secondary power supply sources can be investigated in a mode characterized by transient processes in the investigated component of aircraft equipment. Based on the experimental data of voltage and input current at the stage of transients in equivalent circuits of secondary power supplies, it is proposed to determine the values of the parameters of reactive elements. Changing the values of reactive elements gives information about the technical condition of the input stages of electrical energy receivers. This makes it possible to monitor the process of degradation of their properties or to diagnose a failure in the event of an abrupt change in reactive parameters. This method is proposed to be used for diagnosing electrical equipment during its operation on board the aircraft. This work is devoted to the development of methods for determining the parameters of secondary power sources of aircraft electrical equipment, characterizing its reactive properties.

Purpose. Railway safety during the operation of freight cars largely depends on the reliability, fatigue resistance and durability of the cast bearing elements of the three-element bogie, especially the side frames. Premature failure of cast frames occurs mainly due to undetected latent defects in the foundry. To eliminate these problems, it is advisable to develop an alternative native all-welded side frame for a bogie with an axle load of 23.5 tnf, which can be interchangeable with the cast structure. Methodology. Mathematical modelling approaches were used to determine the stress-strain state of an all-welded structure under the influence of regulated loads and to assess its strength in accordance with current national and modern world standards. Findings. Prototypes of the all-welded side frame structure were subjected to accelerated fatigue tests. The tests have experimentally proved that the cyclic durability of the developed side frame is significantly (2...4 times) higher than the cyclic durability of cast side frames. Originality. A comparative analysis of the permissible stress amplitudes in different zones of the all-welded side frame during long-term operation based on 107 load cycles in accordance with the current standard for the strength of railway cars and modern approaches to determining the fatigue resistance of welded joints showed the insufficient conservatism of the national standard for assessing the fatigue strength of welded joints, which was taken into account when developing a new design of the all-welded side frame. Practical value. In addition to increasing reliability, possible increase in overhaul mileage and warranty period of side frames by ensuring a high level of fatigue resistance and durability, the welded structure can ensure the accuracy of the base frame size, reduce the weight of unsprung masses, which should reduce wheel wear and improve the running characteristics of railway carriage bogies. Reducing the cost of introducing all-welded side frames into mass production compared to the use of foundry technology for the manufacture of these structures and the fact that the cost of manufacturing an all-welded side frame is generally competitive with a cast structure is also one of the important advantages of our developme

Introduction. The solubility of an active pharmaceutical ingredient plays a major role in drug absorption. Hot melt extrusion is a batch or continuous process that allows creating solid dispersion systems based on various carriers in order to increase solubility and bioavailability of active substances. Development of effective and safe analgesics is one of the most vital tasks of organic and medicinal chemistry. An innovative non-opioid analgesic with very low toxicity and low dosage, but practically insoluble in water, was used in this work. It was suggested to obtain a solid dispersion by hot melt extrusion in order to increase bioavailability.Aim. Development a hot melt extrusion technology for production of a solid dispersion system of PAV-0056 as an active substance and Plasdone™ S-630 as a polymeric carrier to increase the solubility.Materials and methods. PAV-0056 (methyl-2-(7-nitro-2-oxo-5-phenyl-3-propoxy-2,3-dihydro-1H-benzo[e][1,4]diazepin-1-yl)acetate) (JSC "Organica", Russia) Figure 1; Plasdone™ S-630 (Boai NKY Pharmaceuticals Ltd., China); PEG-1500 (Clariant, Switzerland); acetonitrile for chromatography (Thermo Fisher Scientific, Germany). Extrudates were obtained using a HAAKE™ MiniCTW co-rotating twin-screw laboratory extruder (Thermo Fisher Scientific, Germany). Extrudates were examined by optical microscopy and differential scanning calorimetry, and time of water solution stability was determined. The quantitative content of the active substance and related impurities in the 2.5 % solid dispersion of PAV-0056 was determined by HPLC-UV.Results and discussion. Hot melt extrusion process conditions were established for a mixture of 2.5 % PAV-0056 and Plasdone™ S-630. Stability of the extrudate solution in water was studied, the content of the active substance and impurities in the extrudates was determined. Based on the binary mixture, a composition containing 10 % of PEG-1500 was developed. The optimal conditions for the extrusion process were chosen for obtaining a solid dispersion system that meets the requirements of the regulatory documentation for the content of the active substance and impurities.Conclusion. The binary mixture proved to be unsuccessful for the creation of SDS by hot melt extrusion due to significant accumulation of impurities during the extrusion process. By adding PEG-1500 to the composition, it was possible to considerably lower the operating temperature of the process, reduce the impurity content in the extrudate, and maintain satisfactory stability of the PAV-0056 solution in water.