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The results of a study of a preprocessing influence method based on the formation of three-channel images on the accuracy of muscle tissue segmentation models on the computed tomography scans corresponding to the levels of the vertebrae of the thoracic and lumbar spine are presented. Ten models have been trained and tested on the Sparsely Annotated Region and Organ Segmentation dataset. The values of the Dice similarity coefficient and the Intersection over Union in the ranges of 0.9353–0.9421 and 0.8737–0.8885 were obtained. The use of a three-channel approach to the formation of input data increased the accuracy of models of four of the five architectures considered. Trained models can be used to quickly and accurately annotate muscle tissue during the diagnostic process.

Background. Massive rotator cuff tears are up to 40% and can progress to the stage of irreparable ones. Nowadays, there are many treatment options available for irreparable rotator cuff injuries, from conservative treatment and arthroscopic reconstructions to reverse shoulder arthroplasty. Currently, the comparative effectiveness of various treatment methods remains uncertain, and therefore there is no clear algorithm for choosing treatment tactics of such orthopedic shoulder pathologies. The aim of the study is to compare short-term treatment outcomes of patients with irreparable rotator cuff tears using arthroscopic partial rotator cuff repair, latissimus dorsi tendon transfer, pectoralis major tendon transfer and reverse shoulder arthroplasty. Methods. The study enrolled 75 patients who underwent the following types of surgical interventions: partial arthroscopic repair, posterior and anterior arthroscopically assisted latissimus dorsi tendon transfer, pectoralis major tendon transfer and reverse shoulder arthroplasty. Treatment results were assessed using measurements of the range of active movements in the shoulder joint, the ASES and Constant-Murley Score (CMS) questionnaires, the Visual Analog Scale (VAS), assessment of radiographs and MRI. The assessments were performed preoperatively and at 6 and 12 months after surgery. Results. In all groups, there was a statistically significant improvement by all indicators (p0.05). Clinical and functional results at the short-term follow-up after partial rotator cuff repair and various options of latissimus dorsi tendon transfer are largely comparable, while at the same time superior to the results of reverse shoulder arthroplasty and pectoralis major tendon transfer. Conclusions. The use of partial rotator cuff repair and musculotendinous transfers at the short-term follow-up gives comparable and better results in comparison with the use of reverse shoulder arthroplasty, which allows to consider “joint-preserving” interventions as an option in patients with massive irreparable rotator cuff tears.

With the increasing routine workload on radiologists associated with the need to analyze large numbers of images, there is a need to automate part of the analysis process. Sarcopenia is a condition in which there is a loss of muscle mass. To diagnose sarcopenia, computed tomography is most often used, from the images of which the volume of muscle tissue can be assessed. The first stage of the analysis is its contouring, which is performed manually, takes a long time and is not always performed with sufficient quality affecting the accuracy of estimates and, as a result, the patient’s treatment plan. The subject of the study is the use of computer vision approaches for accurate segmentation of muscle tissue from computed tomography images for the purpose of sarcometry. The purpose of the study is to develop an approach to solving the problem of segmentation of collected and annotated images. An approach is presented that includes the stages of image pre-processing, segmentation using neural networks of the U-Net family, and post-processing. In total, 63 different configurations of the approach are considered, which differ in terms of data supplied to the input models and model architectures. The influence of the proposed method of post-processing the resulting binary masks on the segmentation accuracy is also evaluated. The approach, which includes pre-processing with table masking and anisotropic diffusion filtering, segmentation with an Inception U-Net architecture model, and post-processing based on contour analysis, achieves a Dice similarity coefficient of 0.9379 and Intersection over Union of 0.8824. Nine other configurations, the experimental results for which are reflected in the article, also demonstrated high values of these metrics (in the ranges of 0.9356–0.9374 and 0.8794–0.8822, respectively). The approach proposed in the article based on preprocessed three-channel images allows us to achieve metrics of 0.9364 and 0.8802, respectively, using the lightweight U-Net segmentation model. In accordance with the described approach, a software module was implemented in Python. The results of the study confirm the feasibility of using computer vision to assess muscle tissue parameters. The developed module can be used to reduce the routine workload on radiologists.

Introduction. In our earlier research on the role of genetic factors in the development of recurrent urolithiasis, a significant relationship was found between the presence of single-nucleotide polymorphism rs3134057 in the osteoprotegerin (OPG) gene and the development of this disease. The above-mentioned single-nucleotide polymorphism is intronic, therefore, it is unable to involve the structure and functions of the OPG but to affect its expression. Thus, the study of serum OPG level may have diagnostic significance in recurrent urolithiasis.Objective. To study the relationship of serum OPG level with the presence of recurrent urolithiasis, as well as the effect of single nucleotide polymorphism rs3134057 on the OPG level.Materials & methods. One hundred and fifteen volunteers were included in the study from January 2021 to January 2022. Of the 115 participants, 45 (main group #1) were diagnosed with recurrent urolithiasis and localisation of the main stone in one of the ureters, 28 participants (main group #2) had previously suffered a single episode of acute renal colic followed by surgical treatment or stone self-discharge and were stone-free at the time of the study. Forty-two control group respondents were free of urolithiasis, including family history of urolithiasis. The serum OPG levels was determined by enzyme immunoassay using the Human OPG ELISA kit ab100617 ("Abcam plc", Cambridge, UK) according to the manufacturer's advice.Results. The analysis revealed that the serum OPG levels were significantly higher in the main group #1 than in the control group (median: 9.02 vs. 3.635, p = 0.012). When analyzing the relationship between the concentration of OPG in serum and the AA + AG genotype versus GG according to rs3134057 of the OPG gene, no statistically significant difference was found (p > 0.05). The same result was obtained when comparing groups with AA vs. AG vs. GG genotypes (p > 0.05).Conclusion. The present study showed that an increased serum OPG level in patients with recurrent urolithiasis may indicate the presence of a relapse of the disease. Further study in large samples will finally confirm the significance of OPG as a marker of relapse, including in genetically determined forms.

Background. Irreparable anterior-superior rotator cuff tears can cause significant shoulder dysfunction due to the failure of normal biomechanics of the joint, because of the loss of compressive effect of the rotator cuff on the humeral head. Muscle-tendon transfers are an alternative to standard surgical treatment options: debridement of injured tendons, arthroscopic anchor suture, and reverse shoulder arthroplasty. Currently, several options of muscle-tendon transfers are described in the foreign literature, and there is an active discussion over the results of the already proposed techniques, and their improvements, while these techniques are practically not covered in the domestic literature. The aim to describe modern surgical technique options of the muscle-tendon transfers for the treatment of patients with anterior-superior rotator cuff tears based on a review of foreign literature sources. Methods. The search for publications from 1988 to 2022 was carried out in the PubMed/MEDLINE and Google Scholar databases. Results. Nowadays, the most common muscle-tendon transfers options for patients with anterior-superior rotator cuff tears are the sternocostal portion of the of pectoralis major tendon transfer and the latissimus dorsi tendon transfer. A review of foreign literature showed that muscle-tendon transfers are a well-described alternative to standard methods of treating profile patients with a predictable result. Conclusion. Currently, there is no consensus on clear indications for certain types of muscle-tendon transfers in case of anterior-superior rotator cuff tears, there is a lack of data on long-term results. This determines the need of study of the long-term clinical results of use of these methods and develop an algorithm for choosing the tactics of surgical treatment of relevant patients.

In the work, with the help of numerical simulation, the values of technological parameters are established, which provide effective two-beam laser cleaning of quartz raw materials. The optimization of two-beam laser cleaning of quartz raw materials was performed using the MOGA genetic algorithm in the ANSYS Work-bench program. Using the face-centered version of the central compositional plan of the experiment, a regression model of two-beam cleaning of quartz raw materials was obtained. The power density of a laser with the wavelength of 10.6 μm, the power density of a laser with the wavelength of 1.06 μm, the radius of a quartz particle, the radius of an impurity particle, and the processing time were used as variable factors. The maximum temperatures of quartz particles with impurities and quartz particles without impurities were used as responses. The regression model was tested. The results obtained allow us to conclude that there is a necessary correspondence between the regression model and the finite element analysis data. An assessment of the influence of processing parameters on the maximum values of the temperature of quartz particles was made. Optimization of two-beam laser cleaning of quartz raw materials was carried out according to the criterion of minimum processing time when reaching the maximum temperatures of quartz particles with an admixture of the melting temperature and limiting the maximum temperatures of quartz particles without an admixture to values below the melting temperature. Optimization was performed for two combinations of quartz and impurity particle sizes. The parameters obtained as a result of optimization and the parameters obtained as a result of finite element modeling are compared. The maximum relative error of the results obtained using the MOGA algorithm did not exceed 2.5 % when determining the maximum temperatures. As a result of the simulation, processing parameters have been established, the use of which will provide an increase in the productivity of two-beam purification of quartz raw materials.

Introduction. Urolithiasis is a polyethylological disease of the urinary system. Epidemiological data on urolithiasis is disappointing: over the past 30 years, the number of patients with urolithiasis has increased by 48.57%, and the mortality rate has increased by 17.12%. Single nucleotide polymorphisms in various genes can influence the risk of development and recurrence of this disease. Early diagnosis of a patient's genetic predisposition to primary or recurrent urolithiasis is important for the effective prevention of urolithiasis.Objective. To explore the association of SNP (Single Nucleotide Polymorphism) rs3134057 (TNFRS11B), rs851982 (ESR1), rs1540339 (VDR), rs2202127 (CASR), rs526906 (KL) with the development of recurrent urolithiasis.Materials and methods. The observed group consisted of 96 patients with a single-sided ureteral stone, of whom 45 had recurrent urolithiasis; the control group consisted of 51 volunteers. Venous blood samples were collected from all participants, DNA was extracted from the blood and analyzed for each SNP studied by real-time polymerase chain reaction. We analyze the data obtained on genotype and presence or absence of urolithiasis in the participants using a binomial logistic regression model.Results. An association was found between the presence of SNP rs3134057 in the TNFRS11B gene (odds ratio (OR), 1.92; confidence interval (CI): 1.05-3.52; p = 0.031) and the development of recurrent urolithiasis.Conclusion. The association of rs3134057 with urolithiasis relapse leads us to investigating the effect of this SNP on serum osteoprotegerin levels, a product of the TNFRS11B gene.

The relevance. The issues of studying the scale of distribution and causes of engineering-geological processes in the Republic of Belarus are positioned as one of the priority issues among the wide range of geoecological problems. Obtaining such information allows identifying and analyzing the factors of human economic activity that impact the geological environmental state, identifying the emergence and presence of threats in urbanized territories, leading to decrease in the safety and living conditions of humans. The aim of the research is to analyze the causes and degrees of manifestation of the most noticeable in the regional plan engineering-geological processes occurring in Belarus. Objects: urbanized territories, mineral extraction and processing facilities, reclaimed land, phenomena and processes resulting from engineering and geological human activity. Methods: research and classification engineering-geological processes developing on the territory of Belarus; expert and comparative methods were used to systematize and analyze the main factors of their occurrence and development on the territory of the country, based on the results of earlier published works and present time field investigations carried out by the authors. Results. The author's expert evaluation and field methods of research have established that the most common factors of occurrence and activation of engineering-geological processes in the Republic of Belarus include: land reclamation, open-pit mining and subsurface mining, groundwater overexploitation, static and dynamic loads from structures and transport, engineering and human economic activities in urbanized areas, natural climatic conditions, and the genesis and composition of rocks. Engineering-geological processes and the phenomena such as groundwater table drawdown, gravitational processes, local earthquakes, suffusion, frost heaving, flooding, and waterlogging are identified and characterized. The spread of engineering-geological processes and phenomena has both a local character within settlements and covers vast areas of dozens of square kilometers. As a result of the study, the mapping of sources of technogenic impact on the geological environment and the manifestations of engineering-geological processes in the territory of Belarus were compiled.

The paper presents the results of modeling the processes of controlled thermal cracking of quartz glass under the parallel action of two infrared laser beams of different geometries on the material: with maximum intensity in the center and with zero intensity in the center (annular section). To calculate the temperature distribution in the material, the method of Green's functions was used, which allows us to obtain a well-interpreted solution for almost any type of function of surface heat sources. Further, taking into account the quasi-static approach, using the methods of the classical theory of thermoelasticity, thermoelastic microstresses were calculated, both on the surface and in the depth of the material. It is established that the simultaneous use of these two types of laser exposure makes it possible to control the temperature field more efficiently, and create prerequisites for the most stable formation of a microcrack. The simulation results show that with a bi-beam effect, the micromechanical stresses necessary for the formation of a microcrack are realized in shorter time intervals, both on the surface and in the depth of the material, which allows increasing the processing speed by up to 30 %. Strengthening control over the process of controlled thermal cracking can significantly reduce the percentage of defects and improve the quality of the resulting microeletronics products.

The paper presents a numerical simulation of laser separation under the influence of laser beams with wavelengths of 10.6 microns and 1.06 microns on quartz raw material used in the electronics industry in the manufacture of photomasks. The temperature fields obtained by the finite element method and the analytical solution are compared. The temperature distribution to a depth of 50 microns is almost the same when using both methods of solution, while with increasing depth the temperature difference increases by 10 %, which allows using both methods of solution, since in practice the temperature distribution in the near-surface layers, which determines the formation of agglomerates with impurity inclusions, is more important. It is revealed that the efficiency of separation of quartz raw material depends on the processing speed and the energy properties of laser radiation, which allows to choose the optimal processing parameters that ensure the effective formation of agglomerates containing impurity inclusions. Experimental studies of bi-beam laser cleaning of quartz raw material were carried out, which allowedus to determine the optimal processing parameters of quartz raw material for effective cleaning of it from impurity inclusions, that make it possible to manufacture photomasks used in the production of microcircuits with improved performance characteristics.

In 2018, atotal of 30 ornithologists and birdwatchers participated in the work of the RaptorRingingCenterof the Russian Raptor Research and Conservation Network and ringed 615 individuals of 24 species of Birds of Prey and Owls. The leading species that have maximum ringed individuals is Upland Buzzard (Buteo hemilasius) – 118 individuals; it followed by Osprey (Pandion haliaetus) – 88 ind., Steppe Eagle (Aquila nipalensis) – 85 ind., Saker Falcon (Falco cherrug) – 62 ind., Imperial Eagle (Aquila heliaca) – 50 ind., and White-Tailed Eagle (Haliaeetus albicilla) – 47ind. During the last 8 months of 2018 and the first 4 months of 2019 we got an information about 37 ringed raptors (38 recoveries), 36 of them were possible to read and identify. The highest number of recoveries we got from Saker Falcon (12 ind. – mainly they are fledglings), White-Tailed Eagle and Peregrine Falcon (6 ind. recoveries per species).

Reactions of 5,5,5-trichloropent-3-en-2-one Cl3CCH=CHC(=O)Me with arenes in Brønsted superacid CF3SO3H at room temperature for 2 h–5 days afford 3-methyl-1-trichloromethylindenes, a novel class of indene derivatives. The key reactive intermediate, O-protonated form of starting compound Cl3CCH=CHC(=OH+)Me, has been studied experimentally by NMR in CF3SO3H and theoretically by DFT calculations. The reaction proceeds through initial hydroarylation of the carbon-carbon double bond of starting CCl3-enone, followed by cyclization onto the O-protonated carbonyl group, leading to target indenes. In general, 5,5,5-trichloropent-3-en-2-one in CF3SO3H acts as a 1,3-bi-centered electrophile.

Luminescent aerogels based on sodium alginate cross-linked with ions of rare earth elements (Eu3+, Tb3+, Sm3+) and containing phenanthroline, thenoyltrifluoroacetone, dibenzoylmethane, and acetylacetone as ligands introduced into the matrix during the impregnation of alginate aerogels (AEG), were obtained for the first time in a supercritical carbon dioxide medium. The impregnation method used made it possible to introduce organically soluble sensitizing ligands into polysaccharide matrices over the entire thickness of the sample while maintaining the porous structure of the aerogel. It is shown that the pore size and their specific area are 150 nm and 270 m2/g, respectively. Moreover, metal ions with content of about 23 wt.%, acting as cross-linking agents, are uniformly distributed over the thickness of the sample. In addition, the effect of sensitizing ligands on the luminescence intensity of cross-linked aerogel matrices is considered. The interaction in the resulting metal/ligand systems is unique for each pair, which is confirmed by the detection of broad bands with individual positions in the luminescence excitation spectra of photoactive aerogels.

In 2017, a total of 36 ornithologists and birdwatchers participated in the work of the Raptor Ringing Center of the Russian Raptor Research and Conservation Network and ringed 498 individuals of 23 species of Birds of Prey and Owls. The leading species that have maximum ringed individuals is Steppe Eagle (Aquila nipalensis) – 146 individuals; it followed by White-Tailed Eagle (Haliaeetus albicilla) and Osprey (Pandion haliaetus) – 53 individuals per species, Imperial Eagle (Aquila heliaca) – 45 individuals, and Saker Falcon (Falco cherrug) – 42 individuals. During the last 7 months of 2017 and the first 4 months of 2018 we got an information about 37 ringed raptors, 32 of them were possible to read and identify. The highest number of recoveries we got from Eastern Imperial Eagle and White-Tailed Eagle (6 recoveries per species).

The new approach for modeling kinetics of complex spatial self-propagating traveling-wave reactions is proposed. This approach is intended to replace well-known reaction–diffusion equations and self-propagating high-temperature synthesis (SHS) as methods for mathematical modeling of spatial propagation of chemical reactions. A chemical kinetic model for frontal polymerization of metal-containing monomers under this approach is suggested.

As a preparatory stage for implementation of genetic testing for severe combined immunodeficiency under a neonatal screening program, a study was performed in Sverdlovsk Region which concerned quantitative determination of T and B cell neogenesis markers (TREC and KREC, respectively) in blood of conditionally healthy newborns. Archived samples of dry blood spots collected in test-forms for routine neonatal screening were used as biological material for the study of full-term 26 girls and 26 boys who did not exhibit serious illnesses during first year of their life. In addition, we investigated potential effects of foetal gestational age upon the number of TREC and KREC in preterm infants. Blood samples from 55 preterm infants (23 to 36 gestational weeks) were also examined. It was shown that the levels of TREC and KREC increased sequentially with the increased gestation terms, but the quantitative changes of markers showed different dynamics. In this respect, the recommended terms of blood sample collection for SCID screening is entirely consistent with timing of blood sampling for routine newborn screening. An alternative result was obtained with a complete absence of TREC or KREC in blood sample of a newborn, irrespectively of prematurity degree (at valid copy numbers of a control gene) which should serve as an indication for immediate consulting of the child by immunologist and in-depth immunological examination, because it may be a first prognostic sign of a fatal disease. In order to obtain correct cut-off levels for TREC/KREC, additional studies are needed on a larger sample of newborns (1.000 to 5.000), followed by validation of the obtained reference boundaries in studies involving patients with different forms of primary immunodeficiencies.