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Microcells were designed for subsequent modeling of piezoelectric and optical elements on their basis. The development of piezoelectric and optical elements from microcells was carried out and models were prepared for 3D printing. These designs can be used in practice as piezoacoustic or piezoelectric sensors if piezoelectric powder is added to their composition, for example, in ultrasonic flow meters, or used to create optical structures, for example, diffractive optical elements. The key characteristics and coefficients of piezoelectric structures, such as dielectric constant, conversion coefficient, dielectric loss coefficient, mechanical Q-factor, frequency constant, electromechanical coupling coefficient, piezoelectric charge coefficient, piezoelectric stress coefficient, elastic compliance coefficient, degradation rate, Curie point are analyzed. Elements produced by 3D printing will have properties different from those of elements produced by standard methods. These structures open up new opportunities for the development of ultrasonic research, mechanical engineering and instrument making.

A game problem of structural design is defined as a problem of playing against external circumstances. There are two classes of players, namely the “ordinal” and “cardinal” players. The ordinal players, designated as the “operator” and “nature”, endeavor to, respectively, minimize or maximize the payoff function, operating within the constraints of limited resources. The fundamental premise of this study is that the action of player “nature” is a priori unknown. Statistical decision theory addresses decision-making scenarios where these probabilities, whether or not they are known, must be considered. The solution to the substratum game is expressed as a value of the game “against nature”. The structural optimization extension of the game considers the value of the game “against nature” as the function of certain parameters. Thus, the value of the game is contingent upon the design parameters. The cardinal players, “designers”, choose the design parameters. There are two formulations of optimization. For the single cardinal player, the pursuit of the maximum and minimum values of the game reduces the problem of optimal design. In the second formulation, there are multiple cardinal players with conflicting objectives. Accordingly, the superstratum game emerges, which addresses the interests of the superstratum players. Finally, the optimal design problems for games with closed forms are presented. The game formulations could be applied for optimal design with uncertain loading, considering “nature” as the source of uncertainty.

Precision neutron monitors providing continuous monitoring with a statistical accuracy of ~0.15 %/hr are effective for studying cosmic ray variations; therefore, contributions from other error sources should not exceed the contribution of this statistical error. Such possible sources primarily include changes in atmospheric pressure and humidity. The aim of the work is to estimate the barometric effect of the neutron component of cosmic rays for the low-latitude stations Tashkent and Alma-Ata (mountain), including periods of maximum solar activity. The technique developed on the basis of multifactor correlation analysis is applicable to processing data from any detectors of the worldwide network of neutron monitors. As a result, we have obtained annual average barometric coefficients of the neutron component at the stations Tashkent and Alma-Ata. The humidity effect was also estimated for the mid-latitude station Moscow. The study draws the conclusion that the approach considered can effectively solve the problem.

Reclamation of coal waste dumps through the establishment of a stable soil and vegetation cover on their surface contributes to the restoration of ecological systems. Therefore, studying the properties of soils in technogenic landscapes is of current importance. The problem of biological reclamation was studied in the Kizel Coal Basin area. The effectiveness of reclamation was evaluated on several sulfide coal waste dumps. The reclamation methods, as well as the period of soil-vegetation cover formation, varied. Agrochemical properties of the dump soils were studied using unified methods. The NDVI (Normalized Difference Vegetation Index) was calculated based on Sentinel-2 and Landsat 7,8 images. To assess biological activity, phytotesting was used. The lithostrats ranged from slightly acidic to neutral (рН–Н2О = 6.1–6.8); the embryonic soil showed a slightly alkaline reaction (7.9). The embryonic soil, due to the presence of coal particles, had the highest organic matter content (12–7.7%). Depending on the "age" of the soil, the amount of organic matter in the lithostrats varied: for the 7-year-old lithostrat, it ranged from 2.4 to 8.9%, while for the 4-year-old lithostrat, it was less than 1%. The absorption capacity of the lithostrats was similar to that of the background soil. The dump soils were characterized by low levels of nutrients (NPK), with the 4-year-old lithostrat having the lowest N content. The dump soils demonstrated favorable conditions for plant growth, as evidenced by the height and biomass of cress and oats. The calculated NDVI for all dumps ranged from 0.4 to 0.6, indicating the presence of a stable vegetation cover. The implemented reclamation measures proved to be effective.

Background. Some of the most tragic pages in human history are associated with periods of epidemic and pandemic spread of infectious diseases. In the process of studying new infections, doctors and scientists used a variety of analysis methods, some of which were associated with a risk to the life and health of not only the researchers themselves, but also those around them.Objective. Assess the importance and significance of experimental infections in the study of infectious processes.Materials and methods. The method of analyzing data from literary sources was used. The research material was the most modern scientific publications available on the platforms elibrary.ru, Scholar.ru, etc.Results. The research work of domestic scientists on the study of infectious diseases is striking in its significance not only for domestic but also world history. Thus, Danila Samoilovich, in the process of his experimental work, determined an effective method of disinfection (fumigation) during the plague epidemic in Moscow in 1771; Stepan Andreevsky in 1788, through self-infection, confirmed that vaccination would help overcome the anthrax epidemic, G. N. Minch in 1874 determined through self-infection that patients were suffering from relapsing fever, not typhus; D. K. Zabolotny proved the effectiveness of cholera vaccination by his own example; Z. V. Ermolyeva proved through an experiment on herself that some cholera-like vibrios, while in the human intestine, can turn into true cholera vibrios, causing the disease cholera; M. P. Chumakov, as part of an expedition in 1937, identified the causative agent of tick-borne encephalitis, established the carrier of the virus, the antigenic properties of the strains and the characteristic signs of the disease; subsequently, in 1959, he, together with A. A. Smorodintsev proved the safety of vaccination with A. B. strains. Sabina against polio; V. A. Znamensky in the second half of the 50s. through self-infection, confirmed that the causative agent of Far Eastern scarlet-like fever is Y. pseudotuberculosis; M. S. Balayan discovered viral hepatitis E through self-infection in 1981.Conclusion. In the history of preventive medicine, experiments with self-infection have become a vivid illustration of the fight against infectious diseases, because Overall, humanity's centuries-long struggle against infectious diseases is a story of courage, struggle and self-sacrifice. The stories of the people presented in the article admire their courage and self-sacrifice, pursuing lofty goals in the form of saving hundreds and thousands of people’s lives.