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Background. Today, non-alcoholic fatty liver disease (NAFLD) is a very common condition that affects ~ 25 % of the world’s population. The prevalence of NAFLD is expected to increase further in the coming years due to the obesity pandemic, rising incidence of diabetes and other factors. The search for modi­fiable risk factors for NAFLD is relevant and urgent to prevent the spread, morbidity and progression of this disease. Recent studies have shown that vitamin D may be a risk factor, which, due to its pleiotropic effects, modulates liver inflammation and fibrogenesis and can improve the liver response to insulin. But there is no definitive opinion on the relationship between vitamin D level and the risk of NAFLD. The purpose of the study was to investigate the serum level of 25(OH)D in patients with NAFLD and to establish its possible relationship with the development and progression of this disease. Materials and methods. A total of 120 patients (78 wo­men, 42 men) with a diagnosis of NAFLD aged 18 to 60 years were exa­mined. The diagnosis of NAFLD was made based on multimodal ultrasound with steatometry and elastography, increased transaminases in 2 or more measurements, the presence of risk factors such as type 2 diabetes mellitus and/or obesity. Serum 25-hydroxyvitamin D deficiency was considered at its serum level ≥ 20 and 0.05). In patients with NASH and liver fibrosis, the mean level of 25-hydroxyvitamin D was also lower than in all patients with NAFLD/NASH, especially in severe F3–4 fibrosis, although this difference was also non-significant. Normal vitamin D status was observed in only 42 (35 %) patients with NAFLD/NASH, while most people (78 patients, 65 %; P

An analytical method for calculation of local stresses in double-sided butt welded joints at misalignment of welds’ axes is developed. The method is applicable for welded thin-gauge plates with different geometry of welds on the face and root sides under tensile load. In the given calculation example, it was shown that the stresses reach their maximum value in the zone of transition from the root weld to the base metal which is farther from the axis of the face weld. The results of analytical calculations are in good agreement with the results obtained using the finite element method.

The aim of the study is to create a virtual test bench, consisting of optimal design parameters that provide the maximum approximation of the real drying process to the experimental data.Method. Methods of modeling, formalized description, optimal design and management of technological processes and productions are applied. Result. A virtual test bench has been developed that allows real-time determination of the design parameters of drum-type dryers depending on the kinetic patterns of the drying process of various grain crops. As an object of study, the design of a two-section drum dryer was used, each section of which is equipped with a profile channel nozzle that provides a transverse supply of the drying agent through the pouring movable layer of the dispersed product to be dried. An algorithm for calculating the drying process is presented, which makes it possible to determine the fields of temperature and moisture content of grain in a wide range of regime parameters. With the use of CAD, a computer model of this installation was made with the possibility of autonomous rotation and movement of the drums relative to each other. A diagram of the synchronized operation of the moving elements of the installation under conditions of operational reconfiguration of its design in accordance with changes in the kinetic curves has been drawn up.Conclusion. The presented virtual test stand adequately and with high accuracy allows simulating the process of drying materials in a drum dryer; allows you to test the operation of a drum dryer at the development stage, conduct experiments with the highest possible accuracy, select the optimal drying modes for various materials with minimal energy consumption.

Background. Deep surgical site infection (DSSI) is one of the most severe complications in spinal surgery. The timing and nature of DSSI are the determining criteria in the choice of treatment tactics. The uniqueness of the clinical observation is the combination of early DSSI, epidural abscess and angular kyphotic deformity formed after a course of conservative antibacterial therapy in a patient who underwent surgery for degenerative-dystrophic disease of the cervical spine. Correction of angular kyphosis, removal of fractured vertebrae, interbody implants and three-column cervical reconstruction were performed in one surgical session. Case presentation. A 57-year-old patient was admitted to the clinic after staged surgical interventions on the cervical spine for multilevel degenerative stenosis of the spinal canal. The primary surgical interventions were complicated by DSSI in the early period after the second surgery with formation of angular kyphosis of the cervical spine. The patient underwent revision one-stage reconstructive intervention to correct the deformity, decompress the spinal canal, and three-column reconstruction of C3-7 segments. Long-term follow-up showed persistent reduction of pain syndrome, improved quality of life and absence of recurrence of DSSI. Conclusion. The presented case illustrates the possibilities of one-stage revision three-column cervical spine reconstruction for correction of sagittal profile, decompression of intracanal neural structures and ensuring stability of operated segments. Use of DSSI treatment algorithms based on Prinz V. and Vajkoczy P. classification contributes to the selection of the optimal tactics of patient management.

Мета роботи: виявлення закономірностей та ключових факторів стійкості України в умовах збройного повномасштабного вторгнення з боку Російської Федерації. Метод дослідження: аналізу та синтезу подій в Україні. Результати дослідження: виявлено ключові фактори національної стійкості. Теоретична цінність дослідження: результати дослідження доповнюють вже існуючі теоретичні дослідження в сфері національної стійкості, а також дозволили сформувати ключові фактори національної стійкості шляхом аналізу реальних подій в умовах війни, яка за масштабами перевершила всі військові конфлікти на європейському континенті після Другої Світової Війни. Практична цінність дослідження: в межах дослідження наведені практичні заходи уряду та громадян України, а також країн-партнерів, які дозволили зберегти українську державність і чинити ефективний опір агресії з боку Російської Федерації.

Modern research in the field of sociology of science is becoming more complicated due to the constantly growing publication activity of authors. To track trends in sectoral sociology, scientists turn to scientometric methods, but they are not enough. Trends in the development of the sociology of values as a branch of sociology are the subject of the study. The purpose of the work is an assessment of the possibilities of using natural language analysis methods (NLP/NLA) for thematic and theoretical clustering of research in the sociology of values. The design of the study was quantitative and qualitative, it was carried out in two stages. At the first stage, 121 abstracts of a scientific articles were analyzed using text mining, after which their total array was divided into clusters. At the second stage, the results of machine clustering were examined by the method of qualitative text analysis, on the basis of which the limitations and capabilities of the NLP/NLA method were identified for solving the problem of clustering scientific texts. It was found that articles with a more conservative core of theoretical categories (gender studies, migration studies, the theory of globalism) are more amenable to clustering, while theories with a loosely structured and fluid theoretical core (theories using environmental terminology, theories of inequality) are much less amenable to explicit clustering. The results obtained allow us to form a new direction of work with large arrays of scientific texts, associated with their clustering using NLP/NLA. Building clusters enables researchers to work with all texts in a given subject area, and not just with the most cited ones. This, in turn, provides the visibility of all scientific ideas, including those that have not gained popularity/notability.

Objective. To study the antibacterial activity of lysostaphin against staphylococci various species, as well as its effect on the viability of Vero cells. Materials and Methods. Lysostaphin was obtained by genetic engineering. Purification of the protein was carried out on SP-sepharose, the purity was determined by electrophoresis in PAGE by Lamley. The susceptibility to lysostaphin of 9 species 175 strains of staphylococci was studied. Identification was performed by MALDI-TOF MS, antibiotic susceptibility by EUCAST (v. 11.0). The MIC of lysostaphin was studied by the method of serial dilutions with concentrations between 0.015 and 512 mg/l. For 72 hours, the viability of Vero cells with lysostaphin at concentrations of 0.5-32.0 mg/l was determined by the MTT method with counting of living cells according to their growth curve. The results were analyzed by ANOVA followed by Dunnett's test. Results. A kinetic study of S. aureus growth in the presence of revealed an inhibitory effect of endopeptidase (MIC 0.06 mg/l). Lysostaphin was characterized by pronounced activity against clinical methicillinsensitive S. aureus. The MIC ranged between 0.03 and 0.5 mg/l and the MIC50/90 was 0.125/0.5 mg/l. For methicillin-resistant S. aureus MIC50/90 0.25/0.5 mg/l. The MIC50 for MRSE was 2 times higher than for MSSE – 1 mg/l. The maximum MIC value was determined against isolates of S. warneri and S. hominis – 64 mg/l, the lowest for S. saprophyticus – 0.5 mg/l. MIC50 of lysostaphin against MRSA was 4 times lower than that of vancomycin, MIC90 was 3 times lower. Differences in viable cells depending on the concentration of lysostaphin were not found. Conclusions. Significant activity of lysostaphin against staphylococci was revealed, which is several times higher than vancomycin against MRSA. Lysostaphin was also effective against methicillin-resistant S. aureus. The high anti-staphylococcal activity and cytocompatibility of lysostaphin are promising for its further study in the prevention and treatment of staphylococcal orthopedic infections.

Background. Balanced feeding with timely supplemental feeding implementation ensures optimal rates of physical and psychomotor development. It is the most effective way for preventing chronic non-communicable diseases and programming health during human life.Objective. The aim of the study is to analyze the timing of the supplemental feeding administration in infants regarding their physical development.Methods. Online questionnaire was developed via Google Forms. Responses from mothers of 108 children aged from 5 months to 3 years were analyzed. Physical development was evaluated via the WHO Anthro program.Results. The timing of first supplemental feeding implementation corresponded to the Optimizing program on infants feeding in Russian Federation (2019) in 89.8% (n = 97) of cases, after 6 months — 6.5% (n = 7) of cases, and before 4 months — 3.7% (n = 4) of cases. The first supplemental feeding most commonly was vegetable puree (65.7%; n = 71), less often — porridge (18.5%; n = 20), or fruit puree (13.9%; n = 15). The meat puree was implemented after 8 months in 57.4% (n = 62) of cases. The mean of z-score for the body mass index to age ratio in children with late supplemental feeding implementation was − 1.1 ± 0.58. It has turned out to be significantly lower than in case of timely administration: 0.08 ± 0.11; p ≤ 0.05.Conclusion. Late supplemental feeding administration (especially foods with high biological value) resulted in nutritional status violation through body weight deficiency in children both on breastfeeding and formula feeding.

Мета роботи: метою статті є розвиток існуючих методичних підходів щодо оцінювання воєнно-економічних спроможностей країни в умовах війни та мирного стану. Дизайн/Метод/Підхід дослідження: для реалізації мети дослідження проведено її декомпозицію та досліджено: існуючі підходи щодо оцінювання воєнно-економічного потенціалу країни, могутності країни та національної могутності; розкрито поняття критичного навантаження національної економіки; наведено загальноприйняті норми щодо фінансування оборонних потреб; наведено досвід фінансування потреб оборони провідними країнами світу – в умовах Другої Світової Війни; запропоновано методичний підхід щодо оцінювання воєнно-економічних спроможностей країни. Результати дослідження: у статті запропоновано методичний підхід щодо оцінювання воєнно-економічних спроможностей країни. Теоретична цінність дослідження: за результатами дослідження удосконалена існуюча теорія воєнної економіки у контексті розуміння допустимого навантаження на економіку країни в умовах війни та розвитку методичних підходів щодо оцінювання воєнно-економічних спроможностей країни. Запропонований методичний підхід є розвитком існуючої воєнно-економічної думки та воєнно-економічного планування на основі спроможностей. Практична цінність дослідження: запропонований методичний підхід дозволяє оцінити спроможності національної економіки щодо задоволення воєнно-економічних потреб в умовах війни за галузями економіки та видами військового забезпечення з урахуванням показника критичного навантаження на національну економіку, що допоможе спростити та покращити процес прийняття воєнно-політичних рішень. Оригінальність/Цінність дослідження: практична цінність дослідження полягає в тому, що запропонована методика оцінювання воєнно-економічних спроможностей країни дозволяє виявити критичні галузі економіки, оцінити їхні спроможності щодо ресурсного забезпечення військових потреб в умовах війни, на основі чого сформувати та прийняти відповідні управлінські рішення. Результати дослідження можуть бути використані в подальших дослідженнях проблем розвитку воєнно-економічного потенціалу країни, балансування військових та цивільних економічних потреб в умовах війни, а також воєнно-економічного планування на основі спроможностей. Обмеження дослідження/Майбутні дослідження: обмеження дослідження полягає у використанні джерел, що знаходяться у відкритому доступі. Майбутні дослідження вбачаються у подальшому розвитку методичних підходів щодо оцінювання та розвитку воєнно-економічного потенціалу країни. Тип статті: теоретичний, практичний.

Мета роботи: є демонстрація зв’язності набору моделей щодо управління в системах на основі спроможностей в межах відомих теорій (теорії систем, теорія суб'єктивного аналізу). Метод: було використано елементи теорії графів, теорії ймовірності, теорії оптимальності, сценарного підходу, моделі успішності та поняття “активної системи” з теорії суб’єктивного аналізу. Результати дослідження: у статті сформульовано проблемну ситуацію щодо розвитку оборонної системи країни; сформульовано задачу реформування системи оборони, як заходи з переведення системи із стану з незадовільними показниками у стан з задовільними показниками; надано формальний запис оцінки спроможності через умовні ймовірності декомпозиції загальної спроможності; надано опис формалізованого визначення завдань в межах типових сценаріїв оборонного планування; показано зв’язок між відомими моделями щодо управління в системах на основі спроможностей в межах відомих теорій (теорії систем, теорія суб'єктивного аналізу). Теоретична цінність дослідження: в статті було показано, що моделі управління на основі спроможностей є гармонійною частиною класичних моделей теорій систем. Практична цінність дослідження: результати роботи дозволяють значну кількість якісних досліджень у напрямку оборонного планування на основі спроможностей представити за допомогою інструментів формального аналізу. Майбутні дослідження: в статті розглянуто виклад частини задач управління на основі спроможностей на основі лише незначної частини найбільш відомих класичних моделей теорії систем. Подальший розвиток цього напрямку досліджень пов’язаний з формалізацією практичних прикладів щодо планування і оцінювання спроможностей із застосуванням запропонованих моделей. Тип статті: описовий, методичний.

The basis for conducting bioequivalence studies is the determination of the bioavailability of the active substance of the drug at its place of action by establishing the concentration of the drug in biological fluids using sensitive analytical techniques. The bioanalytical technique used should provide reliable results which would lead to satisfactory level of interpretation. To investigate the bioequivalence of rivastigmine preparations, an 8 times more sensitive method (compared to the data in the available literature) for the quantitative determination of rivastigmine in human blood plasma by HPLC-MS/MS was developed. Rivastigmine is extracted from plasma by precipitation of plasma proteins with acetonitrile. Chromatographic separation of rivastigmine and the internal standard was carried out on a YMC Triart C18. 50×2.0 mm (1.9 µm) column in a gradient elution mode with a flow rate of 0.5 ml/min. A 0.1% solution of ammonium hydroxide and acetonitrile were used as mobile phases. The lower limit of the quantitative determination of the method was 25 pg/ml.

Pneumohydraulic pressure amplifiers are widely used in mechanical engineering. Using a pneumohydraulic amplifier makes it possible to minimize the size of the presses while simultaneously multiplying their technological effort. A significant disadvantage of the classical method of force multiplication is the low speed of movement of the working bodies of technological equipment under a hydraulic drive. The article proposes a fundamentally new design of a pneumohydraulic amplifier, in which a high-speed pneumatic cylinder carries out the idling of the technological tool, and force multiplication is carried out only at the stage of the working stroke, which allows many times to increase the performance of the amplifier. This effect is achieved by using a movable hydraulic chamber. The engineering formulas and diagrams presented in the article for calculating the parameters of a new pneumohydraulic amplifier allow engineers to adapt the amplifier to various technological conditions. The economic effect when using the proposed amplifier design is achieved by multiplying the productivity of the press equipment.

In the paper the binary mechanism of the long-distance image transfer in a wire-medium (WM) endoscope is suggested and studied. We have shown that a discrete image formed by a set of point sources TM-polarized with respect to the WM can be transferred from the input to the output of the endoscope in a very broad frequency band. The underlying physics is the formation of local channels by a group of four adjacent wires. It allows the transfer of the near field beyond the Fabry–Perot resonances at which the known canalization mechanism offers the image. Both numerical simulations and experimental measurements confirm the deeply subwavelength resolution on the output WM interface. The binary imaging was studied until the frequencies at which the endoscope length exceeds 5λ. The transfer is possible in the entire investigated frequency range (from 1 up to 4 GHz) except for the frequencies where the Fabry–Perot resonance are not enough suppressed.

One of the modern problems in the field of ecology is the creation of environmentally friendly equipment for monitoring and maintaining trees in parks and forests. The traditional use of forest machines and self-propelled tractors with internal combustion engines has a negative impact on the environment as a result of pollutant emissions, i.e., combustion products and fuel residues. An alternative to this tradition can be the use of mobile robots with remote control of their electric drives when performing such technological operations as pruning bacterial growths of trees and diagnosing the state of tree massifs. The article proposes a fundamentally new mobile robot design for monitoring park trees. The main differences between the robot are the new designs of the body and the walking mechanisms of the mobile robot. These design differences provide the robot with high maneuverability when choosing the path of movement along the tree trunk and reliable holding of the robot body on the tree at a sufficient movement speed to perform diagnostics of the state of tree massifs. The article also describes the dynamic models of the movement of a mobile robot along a tree trunk. It presents the simulation results in the form of graph-analytical dependencies of the robot parameters, which constitutes the scientific aspect of the problem. The main motivation of the conducted research is the creation of environmentally friendly equipment in the form of a mobile robot with a reliable system of retention on the surface moving and sufficient performance to perform park tree monitoring operations.

The aim of the study was to assess the current state of silver birch (Betula pendula Roth.) stands in Ukrainian Polissya, as well as to identify optimal composition resulting in productive and resilient mixed birch forests. It was found that in forests managed by the State Forest Resources Agency of Ukraine, birch stands grow on an area of 352 800 ha, covering 5.6% of the total area of forests in Ukraine. Within the study region of Ukrainian Polissya, birch stands cover 294 900 ha making 12.3% of the total forest area. Naturally originated birch stands were found to dominate in the study region, with 65.4% of vegetative stands and 25.2% of those grown from seeds. However, planted stands significantly prevail in terms of growing stock as compared to natural ones. In Ukrainian Polissya, silver birch trees grow as a part of mixed pine and birch forests on 632 400 ha. Our study found that mixed pine and birch stands with 80-90% of Scots pine and 20-10% of silver birch in the composition are the most productive.

Diabetes mellitus type 1 (DM1) and type 2 (DM2) is one of the most common chronic diseases with high rates of morbidity and mortality. Insulin replacement therapy and other va­rious hypoglycemic means have been used for more than 90 years to control high blood glucose levels, but they cannot accurately mimic the secretion of endogenous insulin, can cause reactive hypoglycemia, and do not exclude the risk of secondary complications of diabetes (nephropathy, neuropathy, retinopathy, vascular pathology). The introduction of new scientific achievements into clinical practice in the future allows optimizing the treatment for diabetes and its complications, which can significantly improve the quality of life of many patients. A very promising method of DM therapy is the use of stem cells (SC) as an almost unlimi­ted source of physiologically competent substitute for primary islets of Langerhans. SC can transform (specialize) into any cell of the body and, unlike others, can divide an indefinite number of times. This allows SC to maintain a certain number of their population and allows for the formation of a whole hierarchy of SC in the body, which are stored in certain depots. And, finally, SC are cha­racterized by the Homing effect — the ability to find the damaged zone and fix itself in it, filling the lost function when introduced into the body. A number of studies and recent meta-analyses suggest that C-peptide, HbA1c levels, and daily insulin requirements improve after treatment of DM with stem cells, meaning that SC therapy may be a safe and effective intervention for some individuals with DM. In DM1, bone marrow hemato­poietic SC are a good source of SC transplantation. In DM2, HbA1c and daily insulin requirements were significantly improved after mesenchymal SC therapy, and bone marrow mononuclear cell therapy significantly reduced insulin requirements and improved C-peptide levels. These encouraging results require confirmation in large, randomized, double-blind studies, as well as with longer follow-up periods to clearly recommend stem cell-based therapy as the standard of DM management.

Large-area high density vertical silicon nanowire arrays are fabricated by metal-assisted chemical etching. Two-dimensional silica colloidal crystal template or laser interference lithography are used to create gold metal nanohole arrays on a silicon substrate, which enables to precisely control the final diameter of the nanowires. The formation of ordered silicon nanowire arrays is due to selective and highly anisotropic etching of silicon induced by the gold patterned mask.

To prevent pest contamination of crops, they are treated with plant defense agents, the action of which is aimed at the destruction or development and reproduction control of hazardous organisms. But also these chemical agents cause pollution of environmental ecosystems. Furthermore, the use of pesticides on honey bees often leads to mass mortality of the bees and contamination of nectar and pollen. Honey, made by the bees of such nectar, may contain pesticide residues that are toxic to a bee brood and harm the viability and productivity of bee colonies. One hundred seventy-two samples of bee honey and 40 samples of dead bees were studied from different regions of Ukraine. Eight hundred thirty-seven bee colonies died from pesticide poisoning of the honey bees in 2021. The bees most died due to thiamethoxam (523 bee colonies), clothianidin 400 (bee colonies), and lambda-cyhalothrin (342 bee colonies). In 2022, the poisoning of the honey bees, from which 1,130 bee colonies died, was caused by seven insecticides. Lambda-cyhalothrin (653 bee colonies), thiamethoxam (352 bee colonies), imidacloprid (342 bee colonies), clothianidin (325 bee colonies), and acetamiprid (320 bee colonies) were most frequently detected. 11 insecticides, 11 fungicides and 2 each of acaricides and herbicides were found in the honey. There were 425 detection cases of insecticides, 285 fungicides, 8 acaricides, and 3 herbicides. In 2021-2022, 16 insecticides of the 3rd toxicity class were found in the dead bees.

Link for citation: Kopanitsa N.O., Demyanenko O.V., Kulikova A.A., Tkach E.V., Shestakov N.I., Stepina I.V. Secondary resources in production of composite building materials based on cement. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 10, рр. 49-60. In Rus. The relevance of the research is caused by the importance of the problem of rational use of natural resources in production of composite building materials. The possibility of partial replacement of natural non-renewable raw materials used in the production of multi-ton concrete and mortar mixtures based on cement with secondary products from the production of various industries will solve the problems of: resource saving, energy consumption and ecology. The construction industry is the largest consumer of by-products of mining enterprises: overburden and waste from mining and processing enterprises, which is hundreds of millions of tons per year. The most studied are the issues related to their use as fine and coarse aggregates in concrete and mortar mixtures for various purposes. The expansion of the possibility of using secondary products of mining enterprises in the production of composite building materials is associated with the production of active mineral additives, fillers in concrete and mortar mixtures, as well as energetically active nanomodifiers. The use of by-products of different chemical composition and dispersion makes it possible to control the processes of structure formation and hardening of composite materials based on cement and to obtain composite materials with the required performance properties. The main goal of the research is to scientifically substantiate and investigate the possibility of using waste from mining enterprises as components in concrete and mortar mixtures based on cement. Objects: modifying additives based on secondary products; composite materials with enhanced performance properties. Methods: determination of the mobility of mixtures, normal density, hardening time, flexural and compressive strength according to SS; thermal analysis; electron microscopy, x-ray phase analysis, colorimetry. Results. The paper introduces the results of studies necessary for the scientific substantiation, development and implementation in the construction industry of the technology for production of building mortar mixtures obtained using secondary products of mining enterprises as well as the comparative results of studies on the effect of a complex additive of microcalcite and nano-SiO2 on the properties of cement systems. It is shown that the introduction of a complex additive increases the compressive strength of cement stone, reduces the consumption of cement without reducing its standard characteristics and improves the performance properties of concrete.