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Abstract The state with effective total moment J eff = 1/2 stabilized by the spin-orbit coupling is known to suppress Jahn-Teller distortions and may induce a strong exchange anisotropy. This in turn may lead to the formation of an elusive spin-liquid state in real materials. While recent studies have demonstrated that such a situation can be realized in 3d transition-metal compounds such as those based on Co2+ and Cu2+, diagnosis of J eff = 1/2 state remains challenging. We show that resonant inelastic X-ray scattering is an effective tool to probe this state and apply it to CuAl2O4, material where Cu2+ ions were previously proposed to be in the J eff = 1/2 state. Our results unambiguously demonstrate that, contrary to previous expectations, a competitive (to J eff = 1/2) Jahn-Teller state realizes in this compound.

The assessement of PEARL model adequateness was carried out on the basis of temperature and percolate data obtained by means of MSU Large Lysimeters. Lysimeters are used in experimental soil science mostly for investigating water balance and substance or ions transport from observed horizons or full soil profile. PEARL 4 model, the water prediction block of which is built on the basis of classical SWAP model, uses preferential water flow describing mechanism. Systematical observation of experimental soils in MSU Large lysimeters allowed obtaining extensive data on temperature and soil moisture dynamics, as well as percolate from bottom border. Thеsе measurements are unique and can become the basis for adaptation, verification and setting of mass and energy transfer models. It was shown, that mathematical parametric model requires adjustment for reaching reliable values of percolate from bottom border, moisture and temperature profiles. It can be achieved by selection of water retention curve (WTC) approximation parameters. It was noticed that the error for all predicted parameters increases in winter period. Thereby, the use of such matter transfer models in soil are problematic for long-term prognosis. For example, due to the annual error accumulation before the spring season such models cannot be applied for estimation of the risk of ground water pollution with agrochemicals.

Adipose tissue-derived mesenchymal stem are adult stem cells endowed with multipotent abilities and immunomodulatory properties, like mesenchymal stem cells of other origins. Numerous studies show that adipose tissue stem cells are involved in the pathological process and can exhibit pro-inflammatory properties and attract inflammatory immune cells in the neighborhood. Subsequently, inflammation creates a microenvironment leading to adipose tissue dysfunction. Examples of such a process are obesity and type 2 diabetes mellitus, in which adipogenesis is disrupted and insulin resistance is initiated. The aim of this review is to understand the role of adipose tissue stem cells in the pathogenesis of obesity and type 2 diabetes mellitus.

BACKGROUND: The information available to date on the effect of metformin on the transcriptome and secretory capacity of adipocytes in human adipose tissue (AT) is scarce and contradictory. The study analyzed whether metformin in vitro modulates gene expression and secretion of adiponectin and leptin in the AT of subcutaneous (SAT), epicardial (EAT) and perivascular (PVAT) localization of patients with ischemic artery disease (IHD).AIM: To assess the effect of metformin at various concentrations (1 and 10 mmol / L) on the level of expression of adiponectin and leptin genes and their content in adipocytes of subcutaneous, epicardial and perivascular AT of patients with IHD.MATERIALS AND METHODS: The study included 134 patients with IHD and indications for direct myocardial revascularization by coronary artery bypass grafting (CABG). During the operation, biopsies of SAT, EAT and PVAT were obtained for 3–5 gram, which served as a source of adipocytes. Isolated adipocytes were cultured for 24 hours with and without metformin (1 and 10 mmol / L). After a day of incubation, the expression of the ADIPOQ and LEP genes and the level of secretion of adiponectin and leptin in the culture medium of adipocytes were determined. Statistical processing was performed using the GraphPad Prism 6 software package (GraphPad Software, La Jolla, CA, USA) and Statistica software, 6.1 (Dell Software, Inc., Round Rock, TX, USA).RESULTS: The adipocytes of the EAT and PVAT of patients with IHD were characterized by an imbalance in the adipokine system, manifested by a low level of ADIPOQ expression and a high LEP expression in comparison with adipocytes of the SAT. Metformin increased the level of ADIPOQ expression and its secretion by adipocytes regardless of their location, while a low concentration (1 mmol / L) in adipocytes of EAT had a stronger effect compared to 10 mmol / L. Metformin had a multidirectional effect on the level of leptin in adipocytes, which depended on their localization: both in low (1 mmol / L) and high concentrations (10 mmol / L), the drug reduced the level of LEP expression and protein secretion in the culture medium of adipocytes of the SAT. EAT had no significant effect on adipocytes. In PVAT, metformin increased the expression and secretion of leptin regardless of concentration.CONCLUSION: Metformin has a direct effect on adipocytes in SAT, EAT, and PVAT and is able to modulate their activity, which is a promising strategy for maintaining the balance of adipokines in AT, especially epicardial and perivascular localization.

Introduction. Adipose tissue (AT) is a potential source of ceramides. Of particular interest is the expression of de novo ceramide synthesis enzymes in the AT of the heart and blood vessels localized in close proximity to the lesion. Male gender and age are considered to be one of the main risk factors for coronary heart disease (CHD).Purpose: to study the relationship between the expression of de novo ceramide synthesis enzymes in adipose tissue (AT) and non-modifiable risk factors for cardiovascular disease (CVD) in coronary heart disease (CHD).Materials and methods. The study included 30 patients with coronary artery disease who underwent coronary artery bypass grafting. During the operation, biopsies of subcutaneous, epicardial, perivascular VT (SVT, EAT, PVAT, respectively) were obtained. Expression of genes for de novo ceramide synthesis enzymes (subunits of serine palmitoyltransferases C1 and C2 SPTLC1, SPTLC2; ceramide synthase 1-6 CERS1-6; dihydroceramide desaturase DEGS1) was assessed by quantitative real-time PCR. Statistical analysis of the results was performed using GraphPad Prism 8 (GraphPad Software).Results. Men with CAD were characterized by a higher level of expression of de novo ceramide synthesis enzymes SPTLC1, CERS1, 5 and DEGS1 in EAT and PVAT than women. The expression of the studied enzymes in SAT did not differ significantly depending on gender. In patients older than 60 years, the maximum expression levels of SPTLC1, CERS1,2,6, DEGS1 were found in cardiac VT compared with patients younger than 50 years and 50-59 years (p

Introduction. Ceramides are bioactive lipids that are not only structural components of cell membranes, but also second messengers in the transmission of cell signals. Ceramides are associated with risk factors for cardiovascular disease, may be independent predictors of cardiovascular events and proatherogenic mediators. However, due attention has not been paid to the problem of ceramide accumulation in the adipose tissue (AT) of the heart, while the accumulation of ceramides in adipocytes of epicardial and perivascular AT in coronary heart disease (CHD) is of particular interest, since they are localized in close proximity to the coronary vessels and the focus of the lesion.Objective: to evaluate the expression of de novo ceramide biosynthesis enzymes in the adipose tissue of the heart of various locations in patients with coronary heart disease and acquired heart defects.Materials and methods. The study included 30 patients with CAD, the comparison group consisted of 30 patients with acquired valvular disease (aortic stenosis/insufficiency) without CAD. During the operation, biopsies of subcutaneous, epicardial, perivascular adipose tissue (VT) (SAT, EAT, PVAT, respectively) were obtained. Expression of genes encoding de novo ceramide synthesis enzymes (subunits of C1 and C2 serine palmitoyltransferases: SPTLC1, SPTLC2; ceramide synthase 1-6: CERS1-6; dihydroceramide desaturase: DEGS1) was assessed by real-time quantitative polymerase chain reaction (qPCR) with primers synthesized by Evrogen (Moscow, Russia) on the ViiA 7 Real-Time PCR System (Applied Biosystems, Foster City, California, USA). Statistical analysis of the results was performed using GraphPad Prism 8 (GraphPad Software).Results. Patients with CAD were characterized by higher levels of SPTLC1 mRNA in subcutaneous and epicardial VT and SPTLC2 mRNA in EAT. DEGS1 expression was maximal in SVT and EAT. The expression of ceramide synthase genes in VT of patients with coronary artery disease had tissue-specific features. Expression of the CERS1 gene, encoding the enzyme ceramide synthase-1, which produces ceramides with a fatty acid residue in its composition of 18 carbon atoms (C18), expression of CERS5 and CERS6, encoding ceramide synthase-5 and -6, synthesizing ceramides C14-C16 was maximum in epicardial adipocytes. At the same time, CERS5 expression was higher than CERS6 expression. Gene expression of CERS2, encoding the enzyme ceramide synthase-2, which produces long-chain ceramides and attaches C20–C24 fatty acyl-CoA to the sphingoid base in ceramide, was maximal in subcutaneous adipocytes. While perivascular VT was characterized by a higher expression of the CERS4 and CERS3 genes, which synthesize very long chain ceramides C26 and higher. In the group of patients with valvular disease, VT samples did not differ in terms of SPTLC1, SPTLC2, CERS1, CERS2, CERS5, and CERS6 mRNA levels. However, high expression of CERS4 and DEGS1 was observed in EAT, while CERS3 and CERS4 were expressed in PVAT. When comparing the level of expression of genes for ceramide synthesis enzymes between the two studied groups, it was found that in patients with IHD, the mRNA level of SPTLC1 in SAT and EAT, SPTLC2 in EAT, CERS2 in all types of AT, CERS4 and CERS5 in EAT, DEGS1 in SAT and EAT was higher in compared with patients with valvular heart disease.Conclusion. Regional fat depots of the heart differed in the level of expression of de novo ceramide biosynthesis enzymes. The results obtained indicate the activation of ceramide synthesis along this pathway in adipocytes of predominantly epicardial localization in coronarogenic pathology, which may contribute to the accumulation of long-chain ceramides in the VT of this localization.

. In the last decade, the ESG (environmental, social, governance) paradigm has been actively developing in commercial organization management and investment decision-making. The article examines the impact of ESG factors on the financial state and investment attractiveness of Russian public companies. The concepts of sustainable development and corporate governance constitute the theoretical framework of the research. To analyze the impact of ESG factors on the financial state and investment attractiveness of Russian public companies, we used multiple linear regression models using the least squares method. The empirical evidence is data on 80 organizations from RAEX ESG Ranking of Russian companies based on reports for 2020. A statistically significant positive relationship was found between EBITDA and return on assets, dividend yield, cash flows and ESG factors, as well as a statistically significant negative relationship was found between the price/earnings multiplier, beta coefficient and ESG factors. The study demonstrates that there is a mixed statistically significant relationship between the indicator of financial leverage and ESG factors. At that, ESG factors, which are positioned as necessary and having a positive influence on companies’ activities, can threaten both their financial state and investment attractiveness. Further ESG research imply a more detailed study of the model for assessing the impact of ESG factors on a company’s financial performance and the possibility of integrating financial and non-financial reporting standards.

Introduction: Biases in the measurement of COVID-19 burden and the uncertainty in estimation of the corresponding epidemiologic indexes are known and common phenomena in infectious diseases. We investigated to what extent healthcare access (HCA)-related supply/demand interfered with the registered data on COVID-19 in Poland. Material and Methods: We ran a multiple linear regression model with interactions to explain the geographic variation in seroprevalence, hospitalizations (on the voivodeship – NUTS-2 level) and current (beginning of the 4th wave of COVID cases – 15.09-21.11.2021) case notifications/crude mortality (on poviat – old NUTS-4 level). We took vaccination coverage and cumulative case notifications up to the so called 3rd wave as predictor variables and supply/demand (HCA) as moderating variables. Results: HCA with interacting terms (mainly demand) explained to the great extent the variance of current incidence and most of the variance in the current mortality rates. HCA (mainly supply) was significantly moderating cumulative case notifications until the 3rd wave of cases, thus explaining the variance in seroprevalence and hospitalization. Conclusion: Seeking causal relations between the vaccinationor infection-gained immunity level and the current infection dynamics could be misleading without understanding the socio-epidemiologic context such as the moderating role of HCA (sensu lato). After quantification, HCA could be incorporated into epidemiologic models for improved prediction of the actual disease burden.

Introduction. The topic under consideration is updated by official domestic statistics, according to which more than a third of employees work in harmful and dangerous conditions. During the production process, people get injured and maimed, lose their ability to work. Dozens of fatal incidents are recorded at workplaces every year.The purpose of the study is to show the advantages and prospects of the introduction of gaming computer technologies in the training of workers in labor protection in the agro-industrial complex (AIC).Materials and Methods. The scientific literature devoted to the educational possibilities of digital gaming solutions is considered. In relation to the topic of this study, the potential of a number of computer games, virtual, augmented and mixed reality technologies is evaluated. The well-known and commercially available gaming software is considered in relation to the topics and objectives of occupational safety training. The strengths and weaknesses of this approach are noted.Results. The paper shows how to prepare for the introduction of gaming computer technologies into the occupational safety training system. In particular, it is necessary to identify and systematize the causes of accidents and injuries at work, to focus on industry (in this case, the most typical for agriculture). Special attention should be paid to organizational risks, because if they are neglected, personnel will work in initially dangerous conditions and high- quality training may be useless. The approaches to the organization of training, conducting classes, checking and consolidating knowledge are considered. Digital gaming products that have proven themselves in occupational safety training in various industries, including the agro-industrial complex, are presented. Variants of such training are considered. The use of digital gaming technology tools for the qualitative development of safety techniques, the formation of safe behavior skills and motivation to prevent injuries is justified.Discussion and Conclusion. The results of the work allow us to assert that gaming computer technologies can be successfully used for teaching occupational health and safety in agriculture. This approach has serious advantages in terms of organization, visibility, cost-effectiveness and safety. Certain disadvantages of the method are likely to hinder the widespread implementation of such solutions in occupational safety training at agricultural enterprises for some time. However, in the medium term, it is possible to predict the solution of the identified problems due to the development of the digital games market, virtual technologies and the development of domestic analogues.

The paper deals with problems of the country's economic security and entities, timely resolution of which influences directly the country's national security. The cornerstone of successful existence of any country, especially the Russian Federation, during such complicated period is the presence of effective national economic security system. Analysis of the phenomena connected with using accounting information giving information about financial and economic activity of companies to investors and entrepreneurs in terms of economic security is particularly important in the global market conditions. The paper's purpose is showing the interrelation between economic security and financial statement falsification. In this article, falsification of financial statements is considered within a framework of system and comprehensive approaches as one of possible internal and external threats to financial security of particular economic entities and country as a whole under global market conditions. Using the complex and systematic general-research approaches allows to consider the financial statement falsification problem in the global context as a criminogenic phenomenon similar to international crime. At the present moment, the research in this field is common in the research and professional environment. Analysis of the current situation allows identifying the basic information channel of interaction between the business and society: financial statements, whose authenticity determines the reliability of potential contractors and efficiency of contractual relationships in many aspects.

Over the past decades, the problem of bacterial resistance to most antibiotics has become a serious threat to patients’ survival. Nevertheless, antibiotics of a novel class have not been approved since the 1980s. The development of antibiotic potentiators is an appealing alternative to the challenging process of searching for new antimicrobials. Production of H2S—one of the leading defense mechanisms crucial for bacterial survival—can be influenced by the inhibition of relevant enzymes: bacterial cystathionine γ-lyase (bCSE), bacterial cystathionine β-synthase (bCBS), or 3-mercaptopyruvate sulfurtransferase (MST). The first one makes the main contribution to H2S generation. Herein, we present data on the synthesis, in silico analyses, and enzymatic and microbiological assays of novel bCSE inhibitors. Combined molecular docking and molecular dynamics analyses revealed a novel binding mode of these ligands to bCSE. Lead compound 2a manifested strong potentiating activity when applied in combination with some commonly used antibiotics against multidrug-resistant Acinetobacter baumannii, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus. The compound was found to have favorable in vitro absorption, distribution, metabolism, excretion, and toxicity parameters. The high effectiveness and safety of compound 2a makes it a promising candidate for enhancing the activity of antibiotics against high-priority pathogens.

Introduction. Due to a set of unique properties, for example, the ability to differentiate into different types of connective tissue cells, mesenchymal stem cells (MSCs) are attracting more and more attention from researchers. In 2001, stem cells were found in the stromal-vascular fraction of adipose tissue, which, unlike bone marrow MSCs, show a higher tissue density, grow faster, and are available in large numbers when collected from a small amount of adipose tissue. Currently, a large number of studies are devoted to the study of the morphology and immunophenotype of subcutaneous and visceral adipose tissue stem cells (ASSCs) due to the possibility of easy cell production. Experimental work aimed at studying MSCs of cardiac localization is currently insufficient.Objective: to evaluate the immunophenotype of adipose tissue stromal cells isolated from epicardial and perivascular fat depots in patients with coronary heart disease and acquired heart defects.Materials and methods. The study included 5 patients with ischemic heart disease and 5 with acquired heart disease. The average age is 64.5±2.5 years. All patients had indications for open heart intervention - direct myocardial revascularization by coronary bypass grafting (CABG) or heart valve surgery. SCZhT from subcutaneous, epicardial and perivascular VT biopsies (3-5 years) obtained from patients during surgery (CABG or correction of heart defects) and isolated according to the method of Zeng G. [Zeng G. et al., 2013] . When cells grew to 80–90% confluence, they were digested with 0.25% trypsin and subjected to continuous cell growth and proliferation for subsequent experimental analyses. Flow cytometry analysis was performed on passage 2 cells.Results: The obtained results showed that the MSC culture of the 2nd passage was characterized by increased expression of CD73, CD90, CD105 antigens. Approximately 90% of passage 2 cells derived from epicardial adipose tissue (EAT) and perivascular adipose tissue (PVAT) from a patient with coronary heart disease (CHD) expressed classical MSC markers (CD73, CD90, CD105). In EAT cell culture in a patient with acquired heart disease (ACD), we observed a lower level of co-expression of the main markers of stem cells, in contrast to a patient with CHD (CD90 and CD105 about 61% of cells, and CD90 and CD73 - 58.72%) . The percentage of the studied stem markers on cells isolated from PVAT in a patient with heart disease did not differ significantly from the level of expression of these markers in a patient with coronary artery disease. The level of CD34 expression varied depending on the localization of VT and the disease: thus, in patients with coronary artery disease, the level of CD34 did not exceed 3.5% in both epicardial and perivascular VT. At the same time, a higher percentage of CD34 (32.32%) was found in the epicardial adipose tissue of a patient with PPS. It should be noted that in addition to the main population, both in the EAT culture and in the PVAT, there were 2 minor ones: 1 - CD 90- CD 105+ CD 34-/+ CD 73+ - presumably endothelial population, 2 - CD 90+ CD 105- CD 34- CD 73- - the smallest population.Conclusion: In the early stages of cultivation, cells of the stromal-vascular fraction isolated from epicardial and perivascular adipose tissue express surface markers characteristic of adipose tissue stem cells.

The crystal structure of the cubic double-perovskite Sr2Cr0.84Ni0.09Os1.07O6, grown at high pressure, was solved using intensity data measured at 113 K. The Os site was modelled with a partial Ni occupancy, and the Cr site was modelled with both Os and Ni partial occupancy. The refined structure shows that this cubic form is stable at 113 K.