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With the rapid development of engineering science and technology, tasks related to the calculation of wave processes in elastic medium are becoming more and more relevant. One of the important problems is the search for effective methods for calculating the propagation of harmonic oscillations in elastic mediums, in particular, in semi-infinite spaces. One of these methods is the use of asymptotic boundary conditions of the “radiation conditions” type, which allow us to describe the processes of wave propagation outside the computational domain. In this paper we consider the application of infinitesimal viscosity to derive an asymptotic boundary condition of the “radiation condition” type for the propagation of harmonic oscillations in a semi-infinite elastic space. The results of the study can be used in the design of various devices and structures subjected to the influence of wave processes in elastic mediums, in particular, in the field of soil mechanics.

The article describes the modern vision of the category of “life self-determination” on the example of graduates of engineering and biotechnology programs of a regional university. As part of the study, a review of scientific articles was carried out. We formulated theoretical and instrumental approaches that are relevant for the present time, they are: ensuring a high level of primary professional self-identification of university graduates and high satisfaction with professional competencies; creating conditions for the manifestation of prosocial behavior, satisfaction with the psychological comfort of interpersonal and group interactions; the formed need to participate in the modernization and creation of their modern living environment, including updating the content of the rural way of life; raising awareness among young people about the professions in demand, the needs and priorities of the digital society to develop lifelong learning skills. They provide understanding and modeling of youth policy in the field of professional and life self-determination and contribute to the solution of the state task set in the Decree “On the national development goals of the Russian Federation for the period up to 2030”.

Aim: To study the redistribution of microelements in bone tissue in osteosynthesis in high-altitude destinations. Material and Methods. The study was performed on 72 mongrel dogs of both sexes aged 1-3 years, weighing 10—15 kg. 32 dogs have been experienced the extended leg in lowlands destinations, another group of 32 animals have been experienced elongation produced in high-altitude destinations. The control group consisted of 8 healthy dogs of low mountain areas. The standard technique of surgery has been used in the research. Microelement composition has been studied by atomic absorption spectrophotometer AAS-1 N (Germany) in the long bones and the distraction regenerate. Shapiro —Wilk test was applied to analyze the normality. The data evaluation has been done by Student's t-test for unpaired samples. Results. Calcium and microelement imbalance has been obtained during transosseous osteosynthesis in high-altitude destinations, which causes functional changes in the musculoskeletal system, with similar clinical picture of Kashin — Beck. In the conditions of high-altitude destinations elongation of bones causes changes in microelements in the distraction regenerate. Conclusion. During distraction osteosynthesis in high-altitude destinations phase changes of microelements have been formed in the bone regenerate, which prognoses physiologically the formation of a false joint.

Introduction. The article is devoted to the analysis of national identity as a socio-political phenomenon. The problem under study is the conceptual ambiguity of the content of the concept of «national identity», signifi cant discrepancies in its interpretation. Theoretical analysis. The purpose of the work is to analyze the content of this concept and to study its essential features. The use of logical and critical methods in the analysis of the concept of «national identity» allows us to identify its important features and analyze its dual nature. The theoretical signifi cance of the work consists in the conceptual analysis of the scientifi c concept of «national identity». Conclusion. The scientifi c novelty lies in the formation of the author’s interpretation of the concept of «national identity»: it is the result of achieving a stable relationship between a person and a national community, the acquisition of a set of signs that allow a person to realize his belonging to the ideals, norms and principles of the existence of the nation. The image of a collective «we» is being formed, supported by the institution of the state. The political side of national identity objectifi es the properties of the nation as a collective «we». The dual nature of national identity includes a combination of the activity of state institutions and the free, active nature of a man as a citizen. The presented understanding of national identity can be used in the process of formation and practical implementation of the state identity policy.

Background. Reinfection and recurrence of periprosthetic infection rates during the second stage of revision hip arthroplasty (RHA) remain quite high. Performing preoperative diagnostic aspiration in patients with the installed hip spacer is a controversial issue. Aims of the study: 1) to compare the diagnostic accuracy, specificity and sensitivity of the used infection markers as a part of preoperative diagnostic protocols in order to exclude reinfection in patients with installed hip spacer before the second stage of RHA; 2) to analyze and compare the microbiological spectrum obtained at the stages of RHA. Methods. Diagnostic accuracy parameters of the used infection markers were assessed in order to exclude reinfection/recurrence in 107 patients with installed hip spacer. All patients were divided into two groups. In Group 1 (prospective), blood tests as well as diagnostic aspiration of synovial fluid were performed within the extended diagnostic protocol. In Group 2 (retrospective), the examination was performed according to the screening preoperative diagnostic protocol including blood tests. The used reference range of inflammatory biomarkers was based on the “small criteria” of ICM 2018. According to the results of the intraoperative microbiological examination of peri-implant tissue samples at the first and second stages of RHA, the analysis of detected microflora was conducted in order to assess probable reinfection/recurrence. Results. According to the results of the intraoperative microbiologic examination during the second stage of RHA, reinfection was detected in 40% of cases: in Group 1 — 9 cases, in Group 2 — 31 case. Synovial fluid was obtained from 85% of cases when preoperative diagnostic aspiration was performed. Synovial fluid could not be obtained in 15% cases (dry joint). Conclusion. Performing preoperative diagnostic aspiration before the second stage of RHA in patients with the installed spacer allowed choosing correct treatment tactics in 9% of cases. The parameters of diagnostic accuracy accounted for 82,6%. In the structure of detected pathogens in case of recurrence and reinfection, the representatives of Gram-positive coagulase-negative flora were the most frequent.

Introduction. Based on data on the role of blood erythrocytes in the development and implementation of the vaccine and infectious processes in plague, it was of interest to evaluate changes in erythrocyte surface architecture from the position of searching for informative criteria for the preclinical evaluation of anti-plague vaccines. Aim — using atomic force microscopy to characterize the state of the blood erythrocyte membrane of guinea pigs in response to subcutaneous administration of the vaccine strain Yersinia pestis EV NIIEG and its isogenic derivatives. Materials and methods. For immunization of animals strain Y. pestis EV NIIEG (pYT+, pYV+, pYP+) and its isogenic derivatives Y. pestis KM216 (pYT–, pYV–, pYP+), Y. pestis KM217 (pYT–, pYV+, pYP–), Y. pestis KM218 (pYT–, pYV–, pYP–) were used. Analysis of the erythrocyte membrane was carried out using a Solver P47-PRO scanning probe microscope (NT-MDT, Russia). Results. The most pronounced changes in the surface architectonics of the membrane of guinea pig erythrocytes were established during the first three days of the formation of the immune response to the Y. pestis EV strain NIIEG and its isogenic variant Y. pestis KM217, in the genome of which the pYV plasmid is preserved, administered at a dose of 5 × 108 CFU. A significant increase (p 0.05) in the proportion of transformed cell forms (43.67 ± 3.63% and 37.83 ± 7.03% versus 4.08 ± 0.86% in the control group), root mean square roughness (319 ± 8 nm and 312 ± 7 nm versus 70 ± 6 nm in the control group), Young's modulus (125.73 ± 4.48 kPa and 113.8 ± 5.41 kPa versus 53.03 ± 1.47 kPa in the control group). By the 21st day, the value of these indicators decreased by an average of 2.7, 2.0 and 1.5 times, respectively, indicating restoration of the erythrocyte membrane. Conclusion. The dependence of the changes in the erythrocyte membrane and the rate of their restoration on the plasmid composition of Y. pestis strains has been established. The data obtained contribute to the understanding of the processes of interaction of Y. pestis with the erythrocyte membrane and can be used as additional characteristics in the development of new criteria for preclinical evaluation of plague candidate vaccines.

The article is devoted to the large-scale L. I. Petrazyski’s theory of law, which is filled with new ideas that introduced into methodology, psychology and philosophy of law. The article is targeted to explore the mental structure of consciousness developed by Petrazyski, which is adaptable to a wide range of legal norms and subjective standards for assessing the content of legal experience. Methodology and methods. The dialectical method of discussion was used, supplemented by the deductive method and the method of critical analysis. Results. According to Petrazyski, law itself contains a dichotomy of individual imperative and external instructions for fulfilling duties. Understanding of internal imperative is formed in the mind under the influence of legal experience gained in everyday life. On this basis, an intuitive right is formed that determines a person’s attitude to social activities and personal behavior. The idea of ​​intuitive law runs through all of Petrazycki’s works, which gives him the opportunity to build the concept of a historically inextricable connection between morality and law, resulting in the correct formation of legal norms, changes in social life, and movement towards the common good and justice. It is concluded that Petrazyski’s main contribution to the theory and philosophy of law lies in his firm belief in the unity of law, morality and psychology, as a distinctive characteristic of intuitive law from positive law. Practical implication. The results of the work can be used for further research into Petrazyski’s philosophical and legal ideas of law.

The article delves into the scientific contributions and advancements of the eminent Russian scientist in agricultural tractor construction, Vasily Nikolaevich Boltinsky. (Research purpose) The paper aims to shape and consolidate historical, scientific, engineering and technical concepts regarding the establishment and development of scientific and pedagogical institutions focused on the study of tractor engine operation and machine-tractor units in unsteady modes. It also seeks to underscore the contributions made by Doctor of Technical Sciences, Professor, and Member of VASKHNIL, V.N. Boltinsky. (Materials and methods) The study employs a chronological approach, utilizing historical, scientific, and informational resources, including publications by prominent scientists and original works by the academician himself. The paper also analyzes and summarizes historical facts detailing the role of V.N. Boltinsky in enhancing the design and efficiency of Soviet tractors and machinery units. (Results and discussions) Throughout his career, from assistant to associate professor to vice-president of VASKHNIL, V.N. Boltinsky dedicated himself to developing and testing new models of both foreign and domestic tractor equipment. His extensive experience and years of research culminated in the publication of the monograph «Operation of a tractor engine under unsteady load», which extensively explores the impact of varying loads on engine performance. V.N. Boltinsky successfully solved problems related to enhancing the operational speed of machine and tractor units, as well as innovating the design of agricultural machinery. (Conclusions) The life and professional endeavors of V.N. Boltinsky serve as a shining example of dedication to science, education, and the professional advancement of engineering and scientific professionals. To honor his legacy, an annual scientific and practical seminar entitled «Academician V.N. Boltinsky Readings» is held in Russia, ensuring his contributions continue to be celebrated and remembered.