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This review addresses the modeling approaches for heat transfer processes in oil-immersed transformer. Electromagnetic, thermal, and hydrodynamic thermal fields are identified as the most critical aspects in describing the state of the transformer. The paper compares the implementation complexity, calculation time, and details of the results for different approaches to creating a mathematical model, such as circuit-based models and finite element and finite volume methods. Examples of successful model implementation are provided, along with the features of oil-immersed transformer modeling. In addition, the review considers the strengths and limitations of the considered models in relation to creating a digital twin of a transformer. The review concludes that it is not feasible to create a universal model that accounts for all the features of physical processes in an oil-immersed transformer, operates in real time for a digital twin, and provides the required accuracy at the same time. The conducted research shows that joint modeling of electromagnetic and thermal processes, reducing the dimensionality of models, provides the most comprehensive solution to the problem.

Our knowledge of marine reptiles of the Callovian age (Middle Jurassic) is majorly based on the collections from the Oxford Clay Formation of England, which yielded a diverse marine reptile fauna of plesiosaurians, ichthyosaurians, and thalattosuchians. However, outside of Western Europe, marine reptile remains of this age are poorly known. Here, we survey marine reptiles from the Callovian stage of European Russia. The fossils collected over more than a century from 28 localities are largely represented by isolated bones and teeth, although partial skeletons are also known. In addition to the previously described rhomaleosaurid and metriorhynchids, we identify pliosaurids of the genera Liopleurodon and Simolestes; cryptoclidid plesiosaurians, including Cryptoclidus eurymerus, Muraenosaurus sp., and cf. Tricleidus, and ophthalmosaurid ichthyosaurians, including the iconic Ophthalmosaurus icenicus. These findings expand the ranges of several Callovian marine reptile taxa far to the Eastern Europe, and support the exchange of marine reptile faunas between Western and Eastern European seas in the middle to late Callovian. However, some specimens from the lower Callovian of European Russia show differences from typical representatives of the middle Callovian Oxford Clay fauna, possibly representing the earlier stages of evolution of some of these marine reptiles not yet recorded in Western Europe or elsewhere.

The Altai Mountains of Central and North Asia are biologically rich and comprise a wide range of ecosystems and phytogeographical regions. According to the latest checklist, a total of 321 endemic vascular plant species, including 217 endemic and 104 subendemic taxa, have been recognized in the Altai Mountain Country (AMC). In this study, we conducted species risk assessment, distribution evaluation and conservation gap analysis for the endemic vascular flora of the AMC. The conservation status of 217 endemic species was assessed at the global level using the ConR package. As a result, 197 species were evaluated as potentially threatened, of which 101 are critically endangered (CR), 72 species are endangered (EN), and 24 species are vulnerable (VU). The remaining 20 species were evaluated as not threatened. Furthermore, the AMC was divided into 350 grid cells, with a grid cell size of 50 × 50 km2, for the spatial assessments of the endemic vascular plants. A total of 2657 unique georeferenced occurrences of endemic species were found and analyzed with three endemism indices, species richness (SR), weighted endemism (WE), and corrected weighted endemism (CWE), to quantify geographic patterns and centers of endemism across the whole AMC. The results showed that the endemic species are spread across 186 grid cells and distributed unevenly within the AMC. According to the conservation gap analysis, the main hotspots of endemism (i.e., SR and WE indices) were found at high elevations in the Russian Altai, while the CWE points to the Kazakh Altai as a hotspot, and many such hotspots are currently afforded no formal protections.

Background. The mitochondrial electron transport chain, in particular the respiratory complex I, is one of the main sources of reactive oxygen species (ROS) in living cells. Suppression of the complex I activity in human cells through chemical inhibition or mutations that disrupt the functionality of this complex leads to a significant increase in the content of ROS. The complex I mutants are also known for plants; however, it is still not clear whether the suppression of the activity of this complex leads to an increase in the level of ROS and the development of oxidative stress. Purpose. To study the level of superoxide, hydrogen peroxide and sensitivity to prooxidants in Arabidopsis ndufs4 cells with complex I inactivated by insertional mutagenesis. Materials and methods. A suspension culture of wild-type Arabidopsis cells and a line with knockout the NDUFS4 complex I subunit was used. The level of hydrogen peroxide in the cells was determined using dichlorofluorescein. The superoxide content was estimated by cell staining in the presence of nitroblue tetrazolium. Results. It has been shown that inactivation of the NADH-dehydrogenase complex in Arabidopsis cells due to the absence of one of its subunits leads to a decrease in the content of superoxide and hydrogen peroxide. It was also shown that the level of ROS in cells treated with the menadione and hydrogen peroxide increased several times in wild-type cells, but remained almost unchanged in ndufs4 cells. Conclusion. Suppression of the activity of the NADH dehydrogenase complex in plant cells, but not in animal cells, leads to a decrease in the content of both hydrogen peroxide and superoxide. Cells of ndufs4 line have an increased ability to detoxify ROS, possibly associated with the constant mobilization of antioxidant defense systems.

Corruption is one of the global problems of humanity, it is the reason for a significant decrease in the efficiency of economic systems. Anti-corruption measures are an important task for any state. However, in practice the anti-corruption policies based on the models of classical law and economics are not effective enough. Using the methodology of behavioral economics, we have made an attempt to improve the classical approach to combating corruption. This article provides an analysis of the factors of corruption, methods of combating corruption, reasons for the low effectiveness of anti-corruption policies on the example of educational organizations. The authors suggest using behavioral economics to improve the classical methods of combating corruption. It is necessary to introduce the concept of hyperbolic discounting and the "present bias" into classical law and economics in order to better understand the impact of anti-corruption policies. We assume that using nudges in practice may enable governments to increase the effectiveness of classical anti-corruption measures.

The determining factor of socio-cultural transformation is industrial and economic modernization, which changes the structure of the world economy as a whole. The leading trend in the development of civilization is the desire for uniformity, which leads to the need to analyze the combination, correlation, interaction of “modernized” and “traditional” forms of development of local communities. The aim of the study is to analyze the impact of the processes of production and economic modernization on the modification of sociocultural development, to determine the relationships and interdependencies of the economy, culture and sociality, to identify cause-and-effect relationships and trends in the evolution of the sociocultural sphere. Materials and methods. The study of the processes of production, economic and socio-cultural transformation within the framework of a polyparadigm approach allows using a set of research paradigms, within which various aspects of modernization are considered. The civilizational approach makes it possible to explain the problem of correlation, interaction of general civilizational universals and local specifics. Results. The article shows that the main trends in the production, economic and socio-cultural development of local communities are formed under the influence of internal and external factors. Modification of the production and economic sphere contributes to the evolution of culture and sociality, determines the structure of the life of local communities, forms a new system of diverse processes of activity. There are destructive tendencies leading to the disintegration of the integrity of the socio-cultural space, a decrease in the stabilizing potential of the traditional way of local communities, followed by pauperization and marginalization of a significant part of the population. The diversification of production and economic activities contributes to the modification of the socio-cultural way of life, the transition from the paradigm of maintaining the stability of traditions to the paradigm of innovative changes. Practical implications. The results can be used for further research into the processes of sociocultural development and in the process of teaching social disciplines.

The impact of various Hodgkin's lymphoma treatment program on the female reproductive function is discussed. The current Russian and foreign literature on this problem is reviewed. Reproductive function was estimated in 247 females with Hodgkin's lymphoma before and after treatment. The irregular menstrual cycle in untreated group of the females with Hodgkin's lymphoma was significantly more frequent when B-symptoms were present (p = 0.0004). Radiotherapy without irradiation of inguinal and iliac areas did not induce amenorrhea irrespective of age, the number of fields and the cumulative local dose per field (as high as 50 Gy). Irradiation of inguinal and iliac areas induced amenorrhea in all females even when low doses (less than 30 Gy) were used. The ABVD treatment program did not result in steady-state ovarian tissue damage. The therapy schedules containing less than 8 g of cyclophosphamide were less toxic to ovarian tissue amenorrhea occurred only in 10.5% of the women. Treatment by the schedules with doses of cyclophosphamide more than 8 g caused amenorrhea in 26.6% of the patients. A high correlation was found between the incidence of amenorrhea and the patient' age (p = 0.0002): in women above 25 years irreversible ovarian tissue damage was revealed in 48.4% of cases.

Abstract The Euro-Siberian steppe flora consists of warm- and cold-adapted species, which may have responded differently to Pleistocene glacials and interglacials. Genotyping-by-sequencing individuals from across the distribution range of the pheasant’s eye (Adonis vernalis), we aimed to gain insight into steppe florogenesis based on the species’ evolutionary history. Although the primary area of origin of the species group comprising A. vernalis, A. villosa and A. volgensis is in Asia, our results indicate that recent populations of A. vernalis are not of Asian origin but evolved in the southern part of Europe during the Pleistocene, with Spanish populations clearly genetically distinct from the Southeastern European populations. We inferred that A. vernalis migrated eastwards from the sub-Mediterranean forest-steppes of Southeastern Europe into the continental forest-steppe zone. Eastern European populations had the highest private allelic richness, indicating long-term large population sizes in this region. As a thermophilic species, A. vernalis seems unlikely to have survived in the cold deserts of the Last Glacial Maximum in Western Siberia, so this region was likely (re)colonized postglacially. Overall, our results reinforce the importance of identifying the area of origin and the corresponding ecological requirements of steppe plants in order to understand the composition of today’s steppe flora.

Monitoring of cardiospecific markers is significant during intensive care.The objective: to compare the diagnostic and prognostic significance of cardiac markers in newborns with somatic and surgical pathology.Subjects and Methods. The study included 76 newborns aged 1 to 14 days with somatic or surgical disorders. The changes in the concentration of cardiomarkers in newborns and their relationship with echocardiography data and non-invasive hemodynamic parameters are presented, their prognostic ability is assessed.Results. Rigidity of non-invasive hemodynamic parameters, and echocardiography data was revealed. In the somatic group, regression of NT-proBNP from 8,307 ng/ml (3,600; 9,000) to 1,717 ng/ml (1,041; 5,011) was regarded as a marker of resolution of hypervolemia against the background of cardiovascular maladaptation. The increase in NT-proBNP from 4,710 ng/ml (3,400; 6,989) to 7,987 ng/ml (3,397; 9,000) in the postoperative period requires a revision of the infusion therapy program with the priority of volume restriction.Conclusions. Stabilization of the condition of patients in the groups is accompanied by a decrease in the concentration of markers of myocardial tension (MB-fraction of creatine phosphokinase, troponin T).Measurement of NT-proBNP concentration allows assessment of fluid overload in critically ill neonates.

Heat and moisture exchange filters create additional dead space, comparable in volume to physiological, in premature newborns. It makes carbon dioxide remove difficultу. Reducing the dead space volume by increasing the flow in the ventilator circuit can lead to the hypocapnia. Aim of the study was to determine the safety and efficiency of gas flow boost in the ventilator circuit to hypercapnia compensation created by the additional dead space. Material and methods. The effect of the additional dead space created by a heat and moisture exchange filter on hemoglobin saturation and partial pressure of carbon dioxide at the end of expiration in premature newborns at flows of 5 and 6 l/min was studied. Results and discussion. It has been demonstrated that flows of 5–6 l/min satisfactorily compensate for the effect of additional deadspace without hypocapnia. Conclusions. It is possible to recommend the widespread use of heat and moisture exchange filters in newborn weighing at least 1.0 kg during long-term transportation.

A search and analysis has been carried out of English-language 2005–2020 scientifi c literature devoted to methods of obtaining branched (co)polymers of acrylamide, acrylic acid and (met)acrylates in order to obtain novel materials with valuable properties. It has been found that modern methods of controlled radical polymerization are mainly used for this purpose, namely, atom transfer radical polymerization (ATRP), reversible addition-fragmentation chain transfer polymerization (RAFT) and group transfer polymerization (GTP). In most cases, original synthesized compounds were the chain transfer agents in RAFT. Depending on the order of synthesis, a distinction is made between the “core–arms” and “arms–core” approaches. The prospects of using branched polymers of acrylamide, acrylic acid and (met)acrylates for bioconjugation, surface immobilization, tissue engineering, oil production enhancement, and fl occulation are estimated.

From the Middle Jurassic to the Early Cretaceous, metriorhynchid crocodylomorphs inhabited marine ecosystems across the European archipelago. Unfortunately, European metriorhynchids are only well known from Germany, France, and the UK, with the Eastern European fossil record being especially poor. This hinders our understanding of metriorhynchid biodiversity across these continuous seaways, and our ability to investigate provincialism. Here we describe eleven isolated tooth crowns and six vertebrae referable to Metriorhynchidae from the Callovian, Oxfordian, Volgian (Tithonian), and Ryazanian (Berriasian) or Valanginian of European Russia. We also describe an indeterminate thalattosuchian tooth from the lower Bajocian of the Volgograd Oblast, the first discovery of a marine reptile from the Bajocian strata of European Russia. These rare fossils, along with previous reports of Russian thalattosuchians, indicate that thalattosuchians have been common in the Middle Russian Sea since it was formed. Palaeolatitude calculations for worldwide metriorhynchid-bearing localities demonstrate that the occurrences in European Russia are the most northern, located mainly between 44–50 degrees north. However, metriorhynchids appear to be rare at these palaeolatitudes, and are absent from palaeolatitudes higher than 50°. These observations support the hypothesis that metriorhynchids evolved an elevated metabolism but were not endo-homeothermic, especially as endo-homeothermic marine reptiles (ichthyosaurs and plesiosaurs) remained abundant at much higher palaeolatitudes.

This paper presents the results of an experimental investigation of the diffusion combustion scenario of a round hydrogen microjet flowing from a cylindrical thin-walled micronozzle with a diameter of 200 μm when ignited near and at any distance from the nozzle exit. A review of the literature on the research topic is presented and a comparison is performed in dimensionless parameters based on the Reynolds number. It has been established that stabilization of the torch during the expiration of a round microjet of hydrogen is associated with heating of the nozzle by the laminar region of the flame. A hysteresis of the process of diffusion combustion of round hydrogen microjets was discovered depending on the region of ignition of the microjet (laminar or turbulent region of the torch) and on changes in the jet velocity.

The article is devoted to the numerical assessment of the characteristics of the fan of the cooling module of a diesel locomotive. In the work, the authors consider modern methods and approaches to numerical modeling of fans used in cooling systems of railway diesel locomotives. The focus is on fan performance analysis. The results obtained allow us to better understand and optimize fan operation in the context of diesel locomotive cooling systems, which can help improve the efficiency and reliability of these systems as a whole. The study is important for engineers and specialists in the field of railway transport.

The article describes the process of developing a virtual model of a reduced-order cooling module for subsequent integration into a 1D virtual model of a diesel locomotive. A description of the steps in the model creation process is provided, including data collection, selection of mathematical models, and verification and validation procedures. The results of the work show that the created virtual model provides a convenient and accurate tool for analyzing and optimizing the cooling system of a diesel locomotive, which expands the possibilities for optimizing the design and improving the system control algorithms, which in turn leads to increased reliability and efficiency of its operation. The study highlights the prospects for the application of reduced-order virtual models in the railway industry.

Likely drug candidates which are identified in traditional pre-clinical drug screens often fail in patient trials, increasing the societal burden of drug discovery. A major contributing factor to this phenomenon is the failure of traditional in vitro models of drug response to accurately mimic many of the more complex properties of human biology. We have recently introduced a new microphysiological system for growing vascularized, perfused microtissues that more accurately models human physiology and is suitable for large drug screens. In this work, we develop a machine learning model that can quickly and accurately flag compounds which effectively disrupt vascular networks from images taken before and after drug application in vitro. The system is based on a convolutional neural network and achieves near perfect accuracy while committing potentially no expensive false negatives.

For the first time, a list of higher vascular plants of the natural flora of the Ushkurmynker ridge is presented. The list is based on literature data and materials collected during our field surveys and includes 127 species belonging to 94 genera and 37 families. 21 species are rare and endemic for the Altai mountainous country and the Southern Altai. In addition, the following species are registered in the Southern Altai for the first time: Smelowskia calycina (Steph.) C. A. Mey., Draba ochroleuca Bge., Ribes glabrum (Hedl.) Sennikov., Thymus schischkinii Serg., Doronicum oblongifolium DC., Saussurea leucophylla Schrenk., Saussurea krylovii Schischk. et Serg. The most numerous is the Asteraceae family, which includes 20 species. Potentilla is the genera largest of the presented and includes 5 species. We also registered many families that were represented by 1–2 species.

Background. Pregnancy in paroxysmal nocturnal hemoglobinuria (PNH) patients has historically been a high-risk situation. The combination of chronic complement-mediated hemolysis caused by the disease and physiological activation of the complement system during pregnancy, significantly worsened the prognosis for the life. For a long time, there were no effective methods for the PNH treatment, and pregnancy in patients seemed to be extremely risky, as it significantly increased the risk of life-threatening complications. The advent of targeted therapy with eculizumab turned the prognosis of this disease upside down: patients began not only to survive, but also to live comparable to healthy people. A comparative analysis of the course and outcomes of pregnancy in patients with PNH treated with eculizumab and in patients without targeted therapy was carried out. Aim. The study was to evaluate the course and outcomes of pregnancy in patients with PNH, depending on the therapeutic approach. Materials and methods. We analyzed data from 57 pregnancies in 49 women (31 used eculizumab, 26 with supportive care only) observed at the Kulakov National Medical Research Center for Obstetrics, Gynecology and Perinatology or with remote consultation (23 clinics from 19 cities of Russia). Results. The high probability of pregnancy complications and its adverse outcomes outside of targeted therapy indicates the vital need for its use: all observations were accompanied by complications of varying severity. The course of pregnancy with the eculizumab is generally more favorable: an apparently higher rate of live births and a lower likelihood of complications are registered. Without increasing the incidence of complications, eculizumab significantly improves pregnancy outcomes for both mother and fetus, and does not adversely affect the health of newborns. Conclusion. Thus, eculizumab allows not only to increase the survival rate of patients with PNH, but also to comprehensively improve their quality of life, including the possibility of safe childbirth.

Simulated microcirculation of red blood cells in a microfluidic device reveals two subpopulations of slow-moving cells and persistent cells that retain morphology and membrane structure under oxidative stress.

Unlike antibiotics and heavy metals, nucleic acids exist in the aquatic environment as a part of prokaryotic and eukaryotic microorganisms (bacteria, fungi, etc.) rather than in a free form. In this regard, the most important primary stage of sample preparation of an object for the quantitative analysis of DNA and RNA in natural and wastewaters includes membrane ultrafi ltration of an aqueous sample, followed by its sorption preconcentration on a solid phase carrier. The effi ciency of ultrafi ltration and subsequent sorption of nucleic acids from natural and wastewaters largely depends on the material of fi lters, membranes, and sorbents. Polymeric materials are widely used due to their special properties: the affi nity of polymers for biological objects, the ability to create pores of any required size, good mechanical properties and resistance to the extraction of microorganisms captured. The paper reviews the 15-year-old scientifi c literature on fi ltering, membrane and sorption polymeric materials used to extract nucleic acids from aqueous media and preserve them. Polymeric sorbents for collecting and concentrating DNA and RNA from the liquid phase, as well as storing nucleic acids, are covered. It has been found that ultrafi ltration is used at a relatively low concentration of the analyzed object, followed by extraction of the substance using commercially available kits, including cartridges. Sorption (solid-phase concentration) is used to extract nucleic acids at their relatively high concentration in the analyte. The main polymeric materials used include cellulose and its derivatives (nitrocellulose, cellulose acetate, mixed cellulose nitrate–acetate, diethylaminoethylcellulose, polyethyleneiminocellulose), agarose, dextran, polyestersulfone, polycarbonate, fl uoroplasts, polyacrylates and polymethacrylates, polyaramids, polyamides, polyvinyl alcohol, polyaniline, polycaprolactone, polyacrylamide and polymethacrylamide, polystyrene. Chitosan, modifi ed polycaprolactone, and magnetic particles coated with polydopamine, polyethyleneimine, polyvinylpyrrolidone, polystyrene, or polyamidoamine dendrimer are considered as promising polymers for further research in this fi eld.

Testing the whole volume of memory while estimating the effect of space ionizing radiation on the parameters of flash memory might take long time, which is not acceptable for radiation tests The test time optimization is possible by reducing amount of the tested memory at a cost of predictable loss of accuracy in determining the level of radiation hardness. The nature of data loss under TID irradiation is described. The experimental dependences of number of errors in memory on the relative TID are analyzed based on the test results of nine chip types. A calculated estimate of the amount of memory to test is given, that is sufficient to detect errors in memory cells of the entire solid-state drive for the given detection probability. The experimental data analysis shows that testing 10% of the drive increases the error of the TID hardness level determination no more than 20%. An algorithm for identifying abnormal areas in address space of solid-state drives and flash memory chips is proposed. Knowledge about such areas makes it possible to reasonably choose or further reduce the tested amount of memory.

The aim of the study is to consider the prospects of using resistive memory microcircuits (RRAM, CBRAM) for space applications. Total dose and single event effects in resistive memory test cells and finished CMOS RRAM microcircuits were investigated. A comparative assessment of typical radiative hardness levels for other types of non-volatile memories such as flash, ferroelectric (FRAM), magnetoresistive (MRAM) memory was provided in this study. The main advantages and disadvantages of using various technologies for the manufacture of non-volatile memory microcircuits with increased resistance to ionizing effects are described.