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Introduction. The wide prevalence of varicose veins of the lower extremities and relapses of this disease causes a frequent combination of this pathology with other surgical and traumatological diseases. The expediency of using simultaneous operations is manifested in their obvious economic advantages.Objective. To substantiate the expediency and effectiveness of simultaneous laser thermal obliteration of recurrent veins of the lower extremities and Baker’s cyst.Materials and methods. 9 patients with recurrent varicose veins and Baker’s cyst were operated on. Of these, there were 7 (77.8%) women and 2 (22.2%) men, the average age was 52.8 ± 0.2 years. The average duration of the incidence of varicose veins was 14.1 ± 0.3 years, Baker’s cyst – 3.5 ± 0.1 years. As planned, patients underwent simultaneous laser endovenous coagulation of recurrent veins and intracavitary thermal obliteration of Baker’s cyst.Results. There were no complications, the duration of operations was 40.3 ± 0.4 minutes. The intensity of the pain syndrome in 6–8 hours after surgery was 4.1 ± 0.2 points. On the 10th day, no pain was observed in any patient. The duration of pain was 7.8 ± 0.4 days. Long-term results were studied 12–16 months after completion of treatment in 9 (100%) patients. Recurrent varicose veins were not detected. In 8 (88.9%) patients, complete obliteration of Baker’s cyst was established.Conclusions. Reliable obliteration of Baker’s cyst and recurrent varicose veins, 100% technical success, disappearance of clinical symptoms of this pathology, absence of relapses of both diseases in 8 (88.9%) patients after 12-16 months indicates high efficiency and indisputable prospects of such an approach to the treatment of this category of patients. However, the study is based on a small number of observations, so further accumulation of experience is required to generalize the results of the study.

The article presents a study of the elemental composition of tissues in normal and obese Wistar rats under the influence of premixes from algae Spirulina plat. and Chlorella. Analysis of the mineral composition of the tissues of animals that consumed algae premix with feed did not reveal significant changes in the content of trace elements, with the exception of a signifcant increase in Fe and Cr in the liver (p=0,03). A similar trend of changes in the concentrations of trace elements was observed in animals with modeling obesity by consuming HFD: Cr in the liver, p=0,03.The content of ions in them was distributed according to the degree of decrease: K>Na>Mg> Ca>Fe>Zn>Cu>Mn>Cr. An analysis of the concentration of the element, in comparison with all the studied organs, confirmed this distribution and probably reflects the pool (reserve) of minerals in the body. However, the range of change in the content of each element in tissues is not the same. Thus, the highest content of Fe, Mn and Zn was found in the liver, Na in the kidney, Ca in the pancreas, while Ca and Na were accumulated least of all in the liver, Mn and Mg in the kidneys, and K in the pancreas. Changes and imbalances in the state of the identified bioelements may be a sign of obesity.

Purpose: to establish electrophysiological parameters of the teeth of electrocardiograms and analyze them in animals with different vegetative status.Materials and methods. The removal of electrocardiograms from the Jersey breed cows was carried out according to the methodology of M.P. Roshchevsky, 3-3.5 hours before eating. The ECG received during the study was subjected to mathematical processing using the Conan -4.5 laboratory. The studied animals were kept on the livestock complex with a stall year -round animal content system.Results. In the cows of the Jersey breed, during the study, the numerical values of the -t, a tooth -p and a tooth -r teeth have received numerical values. Analysis of the variability of heart rhythm (VCR) is a widely used method in medical practice to evaluate autonomic regulation and heart condition. A mathematical analysis of heart rhythm rhythms for determining the state of the autonomic nervous system is important for the pathogenetic treatment of many diseases. During a mathematical analysis of electrocardiograms, the breeding features of the variability of the heart rhythm of the Jersey breed cows were established, taking into account the autonomic tone. In this regard, it is advisable to include the assessment of these parameters to include in the basic set of a complex of diagnosis of heart disease in cattle. The study of the cardiovascular system is of great importance in veterinary treatment and preventive work.

The article is devoted to the language of linguistic expert’s opinion as one of aspects of language problem of forensic examination and as a part of general theoretical block in structure of modern forensic expertise. It is stated that the expert’s opinion is a heterogeneous procedural document by its style since it is combining elements of both official and scientific style of speech. A form and a content of constituent parts of the linguistic expert’s opinion are considered from perspective of language. These parts are: introduction, research part and conclusion. It is determined that compliance with principles of drawing up the expert’s opinion and responsible attitude of the expert to the choice of linguistic means when describing process of study will make this procedural document a strong argument when used as an evidence.

Background: Corporate social responsibility (CSR) has a great influence on the sustainability of company development, so it can be considered a business model for business effectiveness. Objective: The objective of the research is to determine the mutual influence of real-estate companies’ activities and CSR effectiveness in different countries. This study examines indicators for assessing companies’ financial stability, CSR, and working capital management's influence on the activity effectiveness of real-estate companies. Methods/Analysis: Questionnaires, the principal component method, the Sobel test, and linear regression analysis are used to evaluate the relationship between CSR and the business performance of autocratic management-style companies. The authors’ algorithm for assessing a company’s financial stability, CSR, and capital management, which affect the efficiency of companies, is proposed. Findings: Empirical analysis has shown that management has no mediating effect on CSR and enterprise performance relationships for companies with high financial stability and working capital, though it has a stimulating effect for low financial stability companies. CSR and business performance have positive relationships in companies, but despite financial stability growing, the autocratic leadership style reduces interest in CSR development. This paper conceptualizes the impacts of CSR on the effectiveness of companies. Novelty: The novelty of this study is to create theoretical and practical provisions aimed at laws and regulations. Doi: 10.28991/ESJ-2023-07-03-08 Full Text: PDF

Consolidation of the efforts in implementation of epidemiological surveillance and control over plague and other dangerous natural-focal infections is an essential aspect in ensuring epidemiological well-being as regards particularly dangerous infectious diseases in the territory of natural plague foci and potentially focal territories located within the borders of the Russian Federation and the Republic of Kazakhstan. The aim of the work was to carry out a joint epizootiological survey of the transboundary territories of the Volga-Ural sandy natural plague focus and the territory of the East Kazakhstan region of the Republic of Kazakhstan (RK) potentially focal for plague over the period of 2019–2022. Materials and methods. Samples of field materials, collected during the epizootiological survey of the territory of Kazakhstan, were studied using bacteriological, molecular-genetic, and immune-serological methods. Results and discussion. We have obtained the current evidence on the spatial-biocenotic structure, the circulation of pathogens of dangerous natural-focal infectious diseases in the transboundary territories of Eastern and Western Kazakhstan. It has been established that the conditions that contribute to the possibility of human infection with plague and other dangerous infectious diseases in case of the aggravation of epizootic situation in the foci or importation of the pathogens into the territory are in place.

The paper considers issues of using a neural network in the thermal engine controller in order to improve the quality of its control and setting conveniences. The study object was a speed controller for the D500 promising locomotive diesel engine. Tasks for design and development of a neural network controller were formulated, and the network input signals were determined. To adjust the neural network, the reinforcement learning method was introduced, where it interacted with the diesel engine computer model in a closed system. The criterion in setting up the network was the accuracy of the control program execution. A system of rewards was assigned, according to which the network was learning. Based on the results of studying the neural network controller influence on the quality of the control system operation, the network minimum possible composition for solving the problem presented was determined. Study results are presented in the form of graphs of rewards alteration during the learning process for various options of the neural network controller structure, as well as the control system simulated transient processes over the entire range of the diesel engine speed.

The aim of the work was to assess the epidemic situation on plague in the world and epizootic activity of natural plague foci of the Russian Federation in 2022. Following the implementation of comprehensive preventive interventions plans, there was a decrease in the epizootic activity of the Gorno-Altai high-mountain and Tuva mountain natural foci, the cessation of plague epizootics in the Central Caucasian high-mountain focus. The total area of epizootics in the Russian Federation in 2022 reached 248.3 km2, which is 7 times less than in 2021. Infected animals were not found in the Tersko-Sunzhensky low-mountain, Dagestan plain-piedmont, Caspian North-Western steppe, Volga-Ural steppe, Trans-Baikal steppe, Volga-Ural sandy, Caspian sandy, East Caucasian high-mountain natural foci. Persistence of tense epizootiological situation in 2023 is predicted for the territory of the Altai Republic and the Republic of Tuva. The prospects of using the GIS portal of the Russian Anti-Plague Institute “Microbe” of the Rospotrebnadzor for an operational assessment of the actual epidemiological situation in natural plague foci are substantiated.

Aim of the study was to analyze the course of coronavirus pneumonia in patients with pneumomediastinum. Material and methods. The study included 139 patients, 71 of whom developed spontaneous pneumomediastinum against the background of coronavirus pneumonia. Laboratory, clinical and radiological data were analyzed and compared. Results. The relationship between the severity of viral pneumonia (3rd–4th degree of severity according to MSCT) and pneumomediastinum was revealed. It was found that spontaneous mediastinal emphysema in patients with COVID-19 signifcantly more often leads to the development of acute respiratory distress syndrome, multiple organ failure and can be a predictor of negative prognosis of the disease outcome. Conclusions. Pneumomediastinum in patients with viral pneumonia caused by a new coronavirus infection is a predictor of severe disease and poor prognosis. With an increase in spontaneous mediastinal emphysema without pneumothorax, it is recommended to perform mediastinotomy according to Razumovsky’s indications, and in case of clinically signifcant concomitant pneumothorax – drainage and revision of the mediastinum.

Research subject. Garnets from silicate-carbonate formations and their halos with skarn mineral associations, developedin the historical mines and pits of the Southern Urals: Zelentsovskaya, Nikolaje-Maximilianovskaya, Akhmatovskaya,Perovskitovaya, Gubensky massif, Praskovie-Evgenyevskaya and Shishimskaya. Aim. To study the nature of silicate-carbonate formations of debatable origin. Materials and methods. The composition of garnets distributed both in silicate-carbonate formations and in rocks with skarn mineral associations was analyzed using SEM-EDS (IPGG RAS) and SIMS (Yaroslavl branch of IPT RAS). Results. The garnets from silicate-carbonate rocks show predominantly a dark to black color, a combination of simple rhombododecahedron and tetragontrioctahedron shapes. In terms of composition, these materials correspond to andradite – Ti-andradite, with the share of shorlmite and morimotoite end-members reaching 30 %. The garnets from calcareous skarns are reddish in color and have a rhombododecahedric habitus. In terms of composition, these garnets correspond to an andradite-grossular isomorphic series, with the share of shorlomite and morimotite end-members not exceeding 3 %. For these garnets, the content of trace and rare-earth elements was determined for the first time, and a posi tive correlation of Ti with U, Y, Zr, Hf and Nb was established. Figurative points on binary diagrams (in coordinate axes of rare-earth content) are plotted as a trend of garnet composition in the grossular–andradite–Ti-andradite series. Garnets from silicate-carbonate rocks, unlike those from skarn mineral associations, are characterized by an increased rare-earth elements content. The main feature of the rare-earth elements distribution spectra in garnets is a positive Eu-anomaly, which is observed in all studied garnets. Conclusion. The data obtained allowed the authors to assume that garnets from silicate-carbonate formations and their halos were formed as a result of a single geological process, essentially close to skarn formation. The results of the petrographic-mineralogical and geochemical studies assume that the “carbonatite” nature of the silicate-carbo nate rocks of the Southern Urals is unlikely.

Tests of friction pairs steel–ice for two grades of structural steel with a yield strength of 540 and 760 MPa were carried out. The dependences of the friction coefficients on the applied load and changes in the ambient temperature are studied. It is shown that the coefficient of static friction of the samples is noticeably higher than the kinetic one, which indicates the adhesion of ice to steel.

DNA sequence composition determines the topology and stability of G-quadruplexes (G4s). Bulged G-quadruplex structures (G4-Bs) are a subset of G4s characterized by 3D conformations with bulges. Current search algorithms fail to capture stable G4-B, making their genome-wide study infeasible. Here, we introduced a large family of computationally defined and experimentally verified potential G4-B forming sequences (pG4-BS). We found 478 263 pG4-BS regions that do not overlap 'canonical' G4-forming sequences in the human genome and are preferentially localized in transcription regulatory regions including R-loops and open chromatin. Over 90% of protein-coding genes contain pG4-BS in their promoter or gene body. We observed generally higher pG4-BS content in R-loops and their flanks, longer genes that are associated with brain tissue, immune and developmental processes. Also, the presence of pG4-BS on both template and non-template strands in promoters is associated with oncogenesis, cardiovascular disease and stemness. Our G4-BS models predicted G4-forming ability in vitro with 91.5% accuracy. Analysis of G4-seq and CUT&Tag data strongly supports the existence of G4-BS conformations genome-wide. We reconstructed a novel G4-B 3D structure located in the E2F8 promoter. This study defines a large family of G4-like sequences, offering new insights into the essential biological functions and potential future therapeutic uses of G4-B. Agency for Science, Technology and Research (A*STAR) Nanyang Technological University Published version Bioinformatics Institute, Biomedical Institutes/A-STAR, Singapore (in part); V.A.K. was supported by a SUNY EMPIRE innovation program scholar grant; Upstate Medical University Cancer Center grant; Upstate Foundation Turn4ACure Fund; research in A.T.P. lab was supported by Nanyang Technological University Singapore; P.J. was supported by the Office of the Permanent Secretary, Ministry of Higher Education, Science, Research and Innovation (OPS MHESI); Thailand Science Research and Innovation (TSRI) [RGNS 64-161]. Funding for open access charge: SUNY EMPIRE innovation program scholar grant, the Upstate Medical University Cancer Center grant; Upstate Foundation Turn4ACure Fund.

Based on the analysis of modern literature, surgical approaches to the treatment of chronic pain syndrome in cancer patients are presented. The definition and classification of chronic pain syndrome is given, its pathophysiology is described. The frequency of occurrence in the population and its dependence on the stage and localization of malignant neoplasm is shown. For practical use, an algorithm for the diagnosis of chronic pain syndrome and the basic principles of its therapy are presented. As the 4th step of the World Health Organization pain relief ladder, surgical methods for the treatment of chronic pain syndrome are separately considered. Three main types of surgical interventions (neuromodulating, neurodestructive and anatomical) are described, indications and contraindications to their use are indicated.

Los autores del artículo estudian la optimización de procesos de negocio en empresas manufactureras. Se estudió el concepto de procesos de negocio y sus funciones. Se eligieron como principales métodos la cognición, el análisis retrospectivo y documental, así como la síntesis, la generalización y la sistematización. Como resultado del estudio, los autores identificaron las principales etapas y aspectos teóricos de los procesos de negocios en empresas manufactureras, identificaron posibles alternativas a la elección estratégica e indicadores de la efectividad del proyecto de inversión, y propusieron modelos de procesos de negocios para las actividades de la empresa.

El artículo considera la optimización de los procesos de negocio en las empresas manufactureras. Los autores consideran el concepto de procesos de negocios, distinguen sus tipos y describen sus funciones. Se presta mucha atención al orden de las medidas tomadas por las empresas manufactureras para optimizar los procesos comerciales presentados en forma de gestión algorítmica. Los principales métodos utilizados a lo largo de la investigación incluyen la cognición, el análisis retrospectivo y documental, así como la síntesis, la generalización y la sistematización. La optimización de los procesos de negocio en cualquier empresa manufacturera es una tarea compleja que requiere el modelado de los procesos de negocio, destacando sus aspectos desafiantes, la reingeniería y el control posterior. Los autores determinan las principales etapas y aspectos teóricos de los procesos de negocios en empresas manufactureras, identifican posibles alternativas a una elección estratégica, definen indicadores de desempeño de proyectos de inversión y proponen modelos de procesos de negocios para las actividades de una empresa.

The study determined the influence of the Central Bank Digital Currency (CBDC) on the financial markets during the COVID-19 pandemic. It investigated if the CBDC had the potential to improve the efficiency and lending power of the financial system. The research relied on secondary data from a range of financial markets, such as the FTSE, MSCI, Gold Index, S&P 500, and Dow Jones, collected during the COVID-19 period. The quantitative approach was employed using the statistical software SPSS to perform descriptive statistics and regression analysis. The results revealed that the financial markets were negatively impacted by COVID-19, but the CBDC saw a higher level of development during the same period. The statistical analysis showed a positive and significant relationship between the CBDC Attention Index, the Uncertainty Index, and various financial market indices, with regression analysis indicating a significant impact of the CBDC Attention Index on all financial market indices except the Gold Index. However, this study has some limitations, including its limited scope of financial markets. Despite this, these results have important implications for academics and policymakers. It is recommended to increase the use of CBDC through well-crafted policies and legislation to fully realize its potential impact on the financial system. Doi: 10.28991/ESJ-2023-SPER-013 Full Text: PDF

Aim. To study the indicators of quality of life (QoL) and health-related quality of life (HRQoL) among medical university students.Materials and methods. In total, 114 people aged 18 to 23 years were included in the study. The participants were divided into two groups. Group 1 consisted of 55 medical students (MS) of the Pacific State Medical University undergoing practical training in the city of Yuzhno-Sakhalinsk (Vladivostok, Russia). In this group, male and female respondents accounted for 41.8% (23) and 58.2% (32), respectively. Group 2 included 59 students of non-medical education (NMS) from the Sakhalin State University (Yuzhno-Sakhalinsk, Russia), with 49.28% (29) male and 50.8% (30) female respondents. The effect of socio-economic factors on HRQoL indicators was determined, along with the main predictors in their decrease.Results. In the structure of diseases defining the 2nd and 3A health groups, diseases of class IX prevailed. Diseases of the circulatory system (I00-I99) were detected in 12% and 24.4% of MS and NMS, respectively. The diseases of class XI were ranked second. Thus, digestive diseases (K00-K93) accounted for 47.8%, and ophthalmic diseases (H00-H59) accounted for 35.5%. A significant physical dysfunction was identified in more than 3% of respondents; 99% of respondents reported a decrease in working capacity. Among MS, 1.7% of respondents demonstrated signs of depression and suffered from pain of varying intensity (44.5%). A decreased social activity was observed in 4% of NMS respondents.Conclusion. The data of QoL monitoring can be used for developing a multi-level scoring system for preventing health disorders among university students. Proposals were made concerning healthy lifestyle management. The model of dynamic monitoring of the health of university students exposed to various risk factors was supplemented. An individual route for rehabilitation and disease prevention for university students was developed based on the study of QoL.

Relevance. Proactive management of the processes of effective realization of the varietal potential of grapes is associated with the need to introduce innovative digital technologies for automated monitoring of heterogeneous data sources characterizing agro-climatic conditions and degradation processes of the biological state of plants. Currently, there is a steady trend aimed at digitalization of the viticulture and winemaking industry. There is a whole complex of scientific, practical, technical, technological tasks associated with the introduction of digital technologies for collecting the necessary information, aggregating it and creating a pre-processing technique for implementing procedures for multifactorial data analysis with their further use in decision support systems. The solution of the above-described tasks of a systemic nature requires the creation of scientific and methodological foundations for the implementation of intelligent adaptive automated monitoring of various objects and processes of agricultural enterprises.Methods. The above technology is based on the complex use of methods of technical vision, neural network classification and detection of grape leaves, evaluation of the quality of training neural network algorithms, video recording methods when using unmanned aerial vehicles (UAVs).Results. The results of the development of information technology for automated neural network detection of signs of deterioration of grape plantations for proactive management of the processes of effective realization of the varietal potential of grapes are presented. The technology allows the vineyard service personnel to promptly receive information about signs of deterioration of the condition of grape plantations based on video recording data of grape plants obtained using UAVs in static and dynamic mode. The results of testing the accuracy of detecting affected leaves showed that the mAP value of the trained neural network is at least 91%, which is sufficient to identify problem areas.

Актуальность. Разработка принципиально новых стратегий и технических решений, приводящих к повышению энергоэффективности и ресурсосбережения систем охлаждения энергонасыщенного оборудования невозможна без создания новых конструкционных материалов с целевыми функциональными свойствами. К перспективным системам охлаждения теплонагруженного оборудования, например, устройств связи пятого поколения 5G, с поверхности которых поступают тепловые потоки высокой плотности (до 1000 Вт/см2), относятся системы, базирующиеся на капельном орошении. Такое охлаждение позволяет повысить интенсивность и равномерность теплоотвода, значительно снизить расход теплоносителя. Но полученные к настоящему времени результаты показывают, что использование традиционных подходов (применение элементов систем охлаждения, изготовленных из стали, меди, алюминия и их сплавов, обработанных шлифовкой или полировкой) не позволяют решить задачу интенсивного охлаждения поверхностей, нагретых до высоких температур. Лазерные методы обработки теплопередающих поверхностей - один из наиболее эффективных способов интенсификации процессов испарения и кипения. В связи с развитием в последнее десятилетие лазерной техники стали доступны финансово возможные технологии создания целевых функциональных поверхностных свойств металлов. Использование на практике модифицированных лазерным излучением теплопередающих поверхностей систем охлаждения может решить ряд проблем, связанных с удовлетворением растущего глобального спроса на энергетические ресурсы, в частности, при интенсификации отвода тепловых потоков высокой плотности от элементов энергонасыщенного оборудования путем смещения кризиса теплообмена второго рода в область более высоких температур. Цель: оценка возможности смещения кризиса теплообмена (эффекта Лейденфроста) в область более высоких температур путем модификации теплопередающих поверхностей нагрева лазерным излучением наносекундной длительности. Методы. Методом лазерной обработки наносекундной длительности на типичных материалах, применяемых на практике при создании элементов систем охлаждения, созданы уникальные текстуры с заданными геометрическими характеристиками. Характеристики текстур определены с использованием оборудования конфокальной и электронной микроскопии. Регистрация эффекта Лейденфроста проводилась на специально изготовленной установке, оснащенной оборудованием теневого оптического метода и высокоскоростной видеорегистрации быстропротекающих физических процессов. Результаты. Установлены режимы воздействия одиночного лазерного импульса наносекундной длительности на поверхность нержавеющей стали и алюминия, гарантирующие образование абляционного кратера. Показана возможность применимости графоаналитической методики для формирования заданной микротекстуры при обработке поверхностей металлов лазерным излучением наносекундной длительности. Лазерная обработка поверхности металлов с энергией в импульсе до 0,6 мДж позволяет за счет формируемой текстуры и супергидрофильных свойств в достаточно широких диапазонах значений управлять характеристиками кризиса кипения 2 рода, а именно температурой Лейденфроста более чем на 110 °С на поверхности алюминия и более чем на 45 °С на поверхности нержавеющей стали в атмосферных условиях при использовании дистиллированной деаэрированной воды в качестве теплоносителя. The relevance. The development of fundamentally new strategies and technical solutions leading to an increase in energy efficiency and resource saving of cooling systems for energy-saturated equipment is impossible without the creation of new structural materials with targeted functional properties. Promising cooling systems of heat-loaded equipment, for example, 5G communication devices emitting highdensity heat fluxes (up to 1000 W/cm2), include systems based on drip irrigation. Such cooling makes it possible to increase the intensity and uniformity of heat removal, and significantly reduce the coolant consumption. However, the results obtained so far show that the use of traditional approaches (the use of surfaces made of steel, copper, aluminum and their alloys, processed by grinding or polishing) does not allow solving the problem of intensive cooling of surfaces that release high-density heat fluxes. Laser strategies for processing heat transfer surfaces are one of the most effective ways to intensify evaporation and boiling. In relation to the development of laser systems in the last decade, financially sound technologies for creating targeted, functional surface properties of metals have become available. The practical use of laser-modified heat-transfer surfaces of cooling systems can solve a number of problems associated with meeting the growing global demand for energy resources, in particular, when intensifying the removal of high-density heat fluxes from elements of energysaturated equipment by shifting the heat transfer crisis of the 2nd kind to higher temperatures. The purpose is to assess the possibility of shifting the heat transfer crisis (Leidenfrost effect) to higher temperatures by modifying heat transfer heating surfaces with nanosecond laser radiation. Methods. Using nanosecond laser processing, unique textures with specified geometric characteristics were created on typical materials used in practice in the design of heat transfer surfaces for heating cooling systems. Texture characteristics were determined using confocal and electron microscopy equipment. The Leidenfrost effect was recorded using a specially made setup with equipment for the shadow optical method and high-speed video recording of fast physical processes. Results. The modes of a single nanosecond laser pulse action on the stainless steel and aluminum surfaces were detected. These modes guarantee the formation of an ablation crater. We showed the possibility to apply the graphic-analytical technique for the formation of a given microtexture during the treatment of metal surfaces with nanosecond laser radiation. Laser treatment of metal surfaces with pulse energy up to 0,6 mJ makes it possible to control the boiling crisis characteristics (2nd kind), in particular, the Leidenfrost temperature, over a wide range of values by more than 110 °C on aluminum surface and by more than 45 °C on stainless steel surface in atmospheric conditions when using distilled deaerated water as a heat carrier due to the formed texture and superhydrophilic properties.

The article presents a draft of clinical recommendations for the diagnosis and treatment of primary hyperparathyroidism in adult patients, which provides a modern examination algorithm, discusses the basic principles of laboratory, instrumental diagnostics and treatment approaches.

In this work, we aim to validate the efficiency of the previously created and patented laboratory test installation for simulating the high-pressure operation of a thermal barrier of high-pressure reservoirs and for determining the thermal conductivity of thermal barrier materials. Simulation of thermal barrier operation in the test installation was carried out under elevated pressures (up to 50–70 MPa). The pressure on the thermal barrier layer was created and regulated by an Instron 5989 test machine as part of the installation. Control of temperature changes and evaluation of the thermal insulation performance were performed by a calculation method based on temperature readings in the control points of the upper and lower rods of the installation. These values were obtained by contact (using thermocouples of surface temperature control) or non-contact (using thermal imaging equipment) methods. A pilot study into the performance of a thermal barrier material “tennesite” was carried out at different pressures. At pressures of 30, 40 and 50 MPa, the thickness of the tested samples comprised 4.64 mm, 4.35 mm and 4.00 mm, respectively. Variations in pressure were established to have a negligible effect on the thermal conductivity of the studied material. Thus, at pressures of 30, 40 and 50 MPa, the temperature drop in the samples comprised 198°С, 188°С and 190°С, respectively. The installation showed high efficiency in simulating the thermal protection of the studied material. Thus, at a layer thickness of 4 mm under the internal pressure of 50 MPa and the working temperature inside the equipment housing up to 300°С, the material is capable of reducing the thermal impact on the protected part of the structure by about three times (from 298.6°С to 108.4°С). The presented design can be used when investigating the behavior of various thermal barrier materials operated under elevated pressures. The results obtained confirm the efficiency of the proposed laboratory installation.

Introduction. One of surgical methods for treatment of aortic valve (AV) pathology is Aortic Valve Neocuspidalization Ozaki procedure (AVNeo). Thus, according to the latest systematic review, freedom from reoperation within one, three, five years after AVNeo was 98%, 97% and 96%. Available references provide few descriptions of reoperations after AVNeo. Aim. To analyze the immediate results of AV reinterventions after AVNeo. Materials and methods. In the medium term, reinterventions after AVNeo were necessary for 11 patients (4.3%). The age of patients ranged from 26 to 69 years. 11 patients who underwent surgery included 6 males and 5 females. Four patients had class III-IV CHF, according to NYHA classification. Three patients had previously been operated on for infective endocarditis (IE), and five patients had bicuspid aortic valve. The duration of follow-up, from AVNeo surgery to reinterventions, ranged from 3 to 43 months. Results and discussion. All patients underwent an isolated AV intervention. The main causes of dysfunction were IE (six patients) and leaflet rupture in the commissural area (five patients). Seven patients underwent aortic valve replacement with mechanical valves, one patient — with aortic homograft valve, one patient — with tissue valve and two patients underwent valve repair. In the early postoperative period, one patient had bleeding with the development of cardiac tamponade and one patient had a haemorrhagic stroke. No patients had ARF, perioperative myocardial damage, sternal infection or permanent pacemaker implantation. Two patients died during the hospital period. Conclusions. AV reinterventions are associated with a high incidence of complications and deaths. Therefore, prevention of IE and commissure enhancement should reduce the frequency of repeated interventions, which is to be confirmed by prospective studies in large cohorts of patients.

Abstract Adenine-DNA-glycosylase MutY is a monofunctional enzyme and catalyzes hydrolysis of N-glycosidic bonds with adenine residues located opposite 8-oxonuanine residues in DNA. Rational design was carried out to construct mutant enzyme forms with altered catalytic activity. Structures of the MutY mutants were calculated by molecular dynamics (MD). Their analysis showed that some of the MutY mutants may have AP lyase activity in addition to hydrolyzing the N-glycosidic bond, as is the case with bifunctional DNA glycosylases. MutY mutants with the A120K or S124K substitution were obtained by site-directed mutagenesis, and their catalytic activities were determined. The S120K substitution was shown to confer additional AP lyase activity, while the A124K substitution completely inactivated the enzyme.