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Introduction. Optical backscatter reflectometry is one of the most promising methods used to examine characteristic parameters relevant to the design of microring resonators. This method paves the way for experimental determination of the coupling coefficient and propagation loss. However, experimental verification of this technique by comparing the transmission characteristics obtained by reflectometry and those directly measured by an optical vector analyzer has not been carried out.Aim. To determine the parameters of microring resonators by optical reflectometry and to calculate on their basis the transmission characteristics of microring resonators. To compare the calculated transmission characteristics with those obtained experimentally using a high-resolution vector analyzer.Materials and methods. The characteristic parameters of silicon-on-insulator microring resonators were investigated using an ultra-high resolution reflectometer. An original algorithm was employed to derive the characteristic parameters of microring resonators from reflectograms. An optical vector analyzer was used to study the transmission characteristics of microring resonators. Numerical modeling of transmission characteristics considering the obtained parameters was carried out according an analytical approach based on partial wave analysis.Results. The obtained values of the power coupling coefficient κ = 0.167 and propagation losses α = 3.25 dB/cm were used for numerical simulation of the transmission characteristics of a microring resonator. These characteristics were found to agree well with those obtained experimentally. The free spectral range of 88.8 GHz and Q-factor of 45 000 were determined.Conclusion. An experimental study of the characteristic parameters of silicon-on-insulator microring resonators was conducted using an optical backscatter reflectometer. The performed comparison of the experimental and theoretical transmission characteristics showed good agreement, which indicates the high accuracy of the determined resonator parameters and, as a result, the relevance of the described method.

W artykule przeanalizowano wyzwania i problemy (m.in. pandemia COVID-19, kryzysy polityczne i społeczne), z jakimi w ostatnim czasie zmierzyło się białoruskie środowisko muzealne. Zarysowano kontekst historyczny rozwoju białoruskich muzeów oraz przedstawiono specyfikę ich przejścia od sowieckiego podejścia i ówczesnych norm do nowego paradygmatu - demokratycznego. Poszukując swojej tożsamości, muzea białoruskie muszą jeszcze przejść trudną drogę transformacji, muszą też poszukiwać nowych form interakcji ze społeczeństwem i sposobu adaptacji do zachodzących zmian.

The MIC genes are located on chromosome 6 in the class I major histocompatibility complex (MHC) region and encode a membrane-bound stress-inducible protein that acts as a ligand to stimulate the NKG2D activating receptor expressed on the surface of the most natural killer cells (NK). Currently, 7 MIC loci are known, of which only MICA and MICB encode proteins and show a significant allelic polymorphism. The MIC gene polymorphism and their location in the HLA region suggests presence of some ethnic and populational differences for the gene frequencies, linkage disequilibrium of distinct loci, and distribution of HLA-MIC haplotypes, thus making it possible to get information on genetic relationship of human populations. The aim of our study was to assess immunogenetic profile of Russian population in Chelyabinsk Region based on the non-classical HLA loci, i.e., MICA and MICB, in the context of worldwide population data. Methods of the study included immunogenetic typing of 100 donors identifying themselves as Russians, taken from the Registry of Stem Cell Donors at the Chelyabinsk Regional Blood Transfusion Station. The 2 loci (MICA and MICB) were typed at basic resolution, using PCR technique with sequence-specific primers (SSP-PCR). Gene frequencies (GF) were calculated using programs for immunogenetic research (Arlequin 3.5).Among Russian population from Chelyabinsk Region, the following characteristics of the MICA gene distributions were found: MICA *008, *002, *010, *009, frequency of > 7%; average frequencies, for MICA *004, *007, *018, *017; whereas MICA *027, *011, *006, *009:02, *049, *012, *016 was registered at a frequency of < 3.5%. MICB gene profile was as follows: MICB *005:02, *004, *002, *008 at a frequency of > 6%; at a frequency of 4% MICB *003, *005:03; MICB *005:01, * 005:04, * 009N, MICB *013, *014 at a frequency of0.5%. As based on calculated genetic distances (according to Ney) for the MICA locus, the dendrogram and scatter plot were designed by means of multidimensional scaling (MDS) method, presenting location of 30 world populations, including data on Russians in Chelyabinsk Region. The smallest genetic distances between the population of Russians from Chelyabinsk Region and other world populations were found between the population of Slovenia, as well as the USA population of European origin. As based on scatterplot obtained by the MDS approach for MICA gene frequencies, using the data of cluster analysis, we have found that the population of Russians from Chelyabinsk Region belongs to a cluster of typical European populations.The obtained patterns could be used for practical purposes to create a registry of stem cell donors in Russia. In addition, the data may be used as a control group for further research in the area of HLA-disease association, and could be also demanded by the specialists in population ethnogenesis.

The mechanism of the interfacial Dzyaloshinskii-Moriya interaction in heavy metal-ferromagnet heterostructures is debated. Here, the authors show the oscillating behaviour of the interaction as a function of the MgO spacer layer thickness, supporting the interlayer exchange coupling mechanism of the Ruderman-Kittel-Kasuya-Yosida type.

Tuberculosis is a widespread infectious disease caused by M. tuberculosis, which is one of the leading causes of death in the world. According to numerous literature data, this is a genetically determined disease, and genetical polymorphism is a mechanism that leads to progression from infection to clinical manifestation. Susceptibility to infection correlates with different genes at several loci, and each individual gene plays a unique role. It is known, that the analysis of individual polymorphic variants of genes does not provide a sufficiently complete picture of the mechanisms of formation of a predisposition to multifactorial pathologies, such as tuberculosis, since their development is based on complex intergenic and gene-environmental interactions, which must be taken into account when predicting the risk of developing active forms of the disease and its severity. The concept of the functioning of cytokines as biomarkers of tuberculosis suggests that their products and interactions play an important role in the immunopathogenesis of the disease, because they form a cytokine chain with unique functions, where the removal of any link in the chain disrupts the entire mechanism of the immuno-inflammatory process. IL-6, together with TNFα and IL-1β, initiate early pro-inflammatory reactions in tuberculosis, stimulating local and systemic inflammatory reactions under participation of all common pro-inflammatory mechanisms with further transition to activation of acquired immunity. Earlier, we carried out a set of studies to evaluate the association of alleles and genotypes of these cytokine genes with a predisposition/resistance to pulmonary tuberculosis in Russians of the Chelyabinsk region. These studies have resulted into assessment of certain distribution patterns of IL-1β, TNFα, IL-6 alleles and their genotypes in pulmonary tuberculosis and its various clinical forms. The following methods were used: isolation of DNA samples from whole blood, genotyping of the studied gene polymorphisms using PCR and RFLP techniques. In this study, we analyzed the intergenic interactions of the genes for the pro-inflammatory cytokines IL-1β, TNFα, IL-6 using the method of reducing multifactor dimension in patients with pulmonary tuberculosis. The program designs optimal models of combinations for the studied genes and their interactions in tuberculosis patients. As a result of this study, a three-locus model IL-6 (-174)*С – IL-1β (+3953)*Т – IL-1β (+3953)*С was established, which was characterized by 100% reproducibility and prediction accuracy of 72%. Among the analyzed polymorphisms, the IL-6 (-174)*C polymorphism possessed the highest predictive potential with 15.27%.

Introduction. The advent of spin oriented electronics, or spintronics, in the late 1980ies has not only revolutionised the very idea of contemporary electronics but has also brought about a major technological breakthrough in the field of information storage and processing. Further progress is associated with the rapidly emerging field of spinorbitronics seeking to put to maximum use the SOC (Spin-Orbit Coupling) related phenomena.Aim. The purpose of this review paper is to outline the major trends in the dynamically developing field of spinorbitronics in the context of evolution of the mainstream spintronics. SOC related effects open up the possibility of creation of a new generation of energy saving devices, a key challenge in electronics in general.Materials and methods. A special effort has been undertaken to make the article appealing to the general reader, especially to specialists in the field of radioelectronics and data processing. To this end, in the description of the complex physics underlying magnetic interactions preference is given to simple term "naive" interpretations.Results. Apart from the analysis of the fundamental features peculiar to the interfaces between ultrathin films of ferromagnetic and heavy metals and related to strong SOC, we discuss specific configurations especially promising for application-oriented research. Among others, these include spin torque microwave (1...50 GHz) oscillators, fast domain walls in racetrack memory and especially magnetic skyrmions.Conclusion. Publication of this paper will facilitate creative interaction between the fundamental and applied research, thus contributing to the development of novel high-performance spintronic devices.

The well-being of an individual, his family and society as a whole is determined by their ability to manage resources and follow the principles of sustainable development. For this, it is necessary to have an appropriate knowledge base, which can be formed only when developing a unified approach, i.e. the development of a sustainable education system. Sustainable education involves three-way education: economic (financial), social and environmental. Within the framework of this work, the necessity of creating a unified sustainable education concept for the younger generation in the Republic of Belarus is assessed, and its practical implementation is proposed through the development of the Trinity mobile application for educational institutions. The Trinity mobile application will allow organizing the educational process and optimizing the work of all stakeholders (government, educational institutions, business, pupils, students) in the field of sustainable development through a single environment of knowledge and achievements.

This article introduces an innovative management system for retail businesses, based on modern computer vision and data analytics technologies. The primary focus is on effective energy management: optimizing inventory control and monitoring employee energy consumption. The system is designed to address several key challenges faced by stores and trading companies. It provides a comprehensive solution for employee monitoring, utilizing computer vision for automated attendance tracking and establishing a detailed absence database. This streamlines supervisory responsibilities and ensures fair payroll distribution, eliminating unjustified payouts for absenteeism. Furthermore, the system revolutionizes inventory management by offering accurate sales statistics through automated data entry and in-depth analytics. It identifies popular items and forecasts future needs, optimizing procurement decisions and preventing losses due to stock shortages.

The article analyses the influence of factors of the work environment, as well as the non-work environment, on the employee's departure from the company. A dataset containing 1470 data rows with 14 attributes belonging to the company's employees was selected for the analysis. The method of self-organising Kohonen maps was used, which allow to study the structure of the data and identify hidden patterns, as well as the method of artificial neural networks, which allow to analyse large amounts of data and find hidden relationships that may not be obvious to humans. In the course of the work, the errors of the methods were determined, several experiments with different number of factors were conducted, and the dependence between the number of factors and the magnitude of the error of the algorithms was revealed. For both methods and each experiment, conjugacy tables were obtained, which contain the classification results obtained by the methods. In addition, a correlation analysis was performed to determine the degree of association between the factors and the target variable.

A brief overview of the generator coherence indicators is presented, the areas and limitations of their applicability are indicated. The application of the area method for the rapid assessment of the transient stability of complex multi-machine electric power system based on the features of the dynamics of the system behavior, determined by the heterogeneous structure of the electrical network, is considered. A distinctive feature of the proposed approach is the use of the characteristics of the heterogeneity of the power system structure, which determine the presence of weak links (or cut-sets) of the electrical network, which are critical from the point of view of a possible violation of the system stability.

The possibilities of the diagnostic use of the singular approach of the distributions of the number of characteristic values of the MMI is effective for differentiating the polarization properties of histological biopsy sections of benign and malignant tumours of the uterus and prostate. Within the framework of evidence-based medicine, the sensitivity, specificity and accuracy of the azimuthal-invariant express (∼15 min) method of Mueller-matrix mapping of polarization-singular states in the differential diagnosis of uterine myoma and adenocarcinoma, as well as adenocarcinoma of the prostate with varying degrees of differentiation have been determined.

In this article, we present a numerical study on stabilization and eigenmodes of the so-called skyrmion chiral spin texture in nanometric dots. The first aim of this study is to identify the appropriate multilayer in a set of Pt/Co/MgO structures with different Co thicknesses that have been previously experimentally characterized. Stabilization occurs if the energy favoring skyrmions is greater than the geometric mean of the exchange and anisotropy energies. Both the energy favoring skyrmions and the anisotropy contribution depend on the Co thickness. The appropriate multilayer is obtained for a specific Co thickness. MuMax simulations are used to calculate the precise static magnetization configuration for the experimental parameters, allowing us select the appropriate structure. Moreover, in view of experimental study of skyrmion dynamics by means of Brillouin light scattering, the eigenfrequency, eigenmode profile, and spectral density are calculated for different dot sizes. Finally, the optimal dot size that allows for a feasible experiment is obtained.

Сomplex intergenic interactions should be taken into account when predicting the risk of adverse course in a pathological process. This presumption is at the heart of evolving multifactorial diseases (ulcerative colitis and irritable bowel syndrome). A single genetic polymorphism seems to be a weak risk factor when predicting the disease evolution and it could not be used as a prognostic model for development of multifactorial pathologies, especially in cases of rare alleles. However, it is well known that the combination of unfavorable alleles of several genes with an additive effect is dangerous. Therefore, identification of such polymorphisms is very important.Previously we conducted a test panel, in order to evaluate associations of alleles and genotypes of some cytokine genes (IL1β, TNFα, IL1rа, IL10, IL6) with predisposal, or resistance for ulcerative colitis and irritable bowel syndrome in the Russian Chelyabinsk region. Distribution of alleles and genotypes of these genes have been assessed in irritation bowel disease (IBD) and ulcerative colitis (UC). The following methods were used: isolation of DNA samples from whole blood, genotyping of the studied gene polymorphisms with PCR, RFLP. A comparative analysis of intergenic interactions between the cytokine genes IL1β, TNFα, IL1ra, IL10, IL6 in the IBD and UC patients was carried out by the Multifactor Dimensionality Reduction method. The analysis is based on the use of polymorphic loci of IL1β, TNFα, IL1ra, IL10, IL6 combinations chosen for analysis of intergenic interactions, with respect to the risk for IBS and UC predisposition. As a result of this study, a fourlocus model IL1β(+3953)*Т/TNFα(-308)*A/IL10(-1082)*G/IL6(-174)*G was identified for IBS, which was characterized by 90% repeatability and prediction accuracy of 74.5%. This model of gene interactions between the cytokine IL1β, TNFα, IL1ra, IL10, IL6 genes had the greatest prediction potential (p < 0.001) in IBS, whereas the model for UC was not statistically significant. The following types of genetic interactions were established: synergism between the IL1β(+3953)*Т and TNFα(-308)*A loci, whereas IL6(-174)*G и IL10(-1082)*G, TNFα(-308)*A seem to be in antagonistic relationships. The study made it possible to establish that the -174G/C IL-6 polymorphism may play a central role and provide intergenic interactions with SNPs of IL1β, TNFα, IL10 for predisposal to irritable bowel syndrome in Chelyabinsk Region of Russia.

The aim of the study was to analyze the uterine and fetoplacental hemodynamics in pregnant women with placenta abnormalities. Materials and methods. Fifty pregnant women with normal placentation (Group 1), 50 women with placenta previa (Group 2) and 28 women with placenta accreta (Group 3) were examined in this study. The ultrasound examination included the traditional fetometry and an assessment of fetus anatomy and localization of the placenta. In addition, the Doppler ultrasound was used to examine the blood flow in the uterine arteries as well as the umbilical artery and the middle cerebral artery of the fetus. The measurements were performed on the 20-22nd, 30-32nd and 35-36th weeks of gestation.Results. According to the data obtained, the blood flow in the uterine arteries of patients with placenta pervia was much higher as compared with women with normal placental localization. The right uterine artery blood flow indices in the placenta previa cases significantly differed from those in women with placenta accreta. The pulsatility index in the right uterine artery was significantly lower in patients with placenta accreta as compared with the two other groups. The data on fetoplacental hemodynamics indicated differences in the umbilical artery blood flow between women with placenta accreta, placenta previa and normal placental localization on the 20-22nd and 35-36th weeks of gestation. Along with the above findings in the uterine and fetoplacental hemodynamics, the parameters of blood flow in the fetal middle cerebral artery did not differ significantly between the three groups of women at any period of gestation.Conclusion. The conditions of placenta accreta and placenta previa are associated with a decrease in the peripheral vascular resistance in both uterine arteries during all periods of gestation. This conclusion is supported by the lower values of the pulsatility index in these blood vessels in comparison to the values in patients with normal placental localization.

The creation of practical devices based on magnetic skyrmions depends on the development of methods to create and control stable individual skyrmions. Here, the authors present a bilayer device that uses dipolar interactions to stabilize skyrmions that can be manipulated using electric currents.

The main object of the work was developed the device based on GaInAsSb diodes for measurement water content in oil. Optical absorption method was used in this device. Three LEDs emitting in the range from 1.6 to 2.4 μm, and one wide-band GaSb/GaInAsSb/GaAlAsSb photodiode were used as sources of radiation and detectors.The device was developed on the basis of selective optical absorption method of detection for measuring water content in oil. As sources of radiation, LEDs emitting in the range from 1.6 to 2.4 μm were used. The results of the experiments showed that the method used makes it possible to measure the water concentration in oil in the range from 0.2 to 40% with an relative error of not more than 2 %.The technical requirements and operating parameters of the used light and photodiodes were established. Investigations of the dependence of the luminescence spectra of LEDs on temperature have shown the importance of using thermal control on the sources and detectors of radiation. The possibility of using one device for different types of oil, as well as oil products during preliminary calibration were shown in the paper. The importance of using a rotary pump for mixing and pumping the analyzed medium and a flow cell was established.