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“Lung-on-a-chip” (LoC) is a microfluidic device, imitating the gas-fluid interface of the pulmonary alveole in the human lung and intended for pathophysiological, pharmacological and molecular-biological studies of the air-blood barrier in vitro. The LoC device itself contains a system of fluid and gas microchannels, separated with a semipermeable elastic membrane, containing a polymer base and the alveolar cell elements. Depending on the type of LoC (single-, double- and three-channel), the membrane may contain only alveolocytes or alveolocytes combined with other cells — endotheliocytes, fibroblasts, alveolar macrophages or tumor cells. Some LoC models also include proteinic or hydrogel stroma, imitating the pulmonary interstitium. The first double-channel LoC variant, in which one side of the membrane contained an alveolocytic monolayer and the other side — a monolayer of endotheliocytes, was developed in 2010 by a group of scientists from the Harvard University for maximally precise in vitro reproduction of the micro-environment and biomechanics operations of the alveoli. Modern LoC modifications include the same elements and differ only by the construction of the microfluidic system, by the biomaterial of semipermeable membrane, by the composition of cellular and stromal elements and by specific tasks to be solved. Besides the LoC imitating the hematoalveolar barrier, there are modifications for studying the specific pathophysiological processes, for the screening of medicinal products, for modeling specific diseases, for example, lung cancer, chronic obstructive pulmonary disease or asthma. In the present review, we have analyzed the existing types of LoC, the biomaterials used, the methods of detecting molecular processes within the microfluidic devices and the main directions of research to be conducted using the “lung-on-a-chip”.

Background. Fractures of the bones that form the knee joint in children are quite rare, accounting for up to 6% of all bone fractures. These include avulsion fractures of the patellar apex as well as tibial tuberosity avulsion fractures, which may result in patellar tendon ossification. Based on literature, the ossification may also occur in cases of primary or chronic (complete or partial) patellar tendon tears. Such a complication is quite rare in pediatric traumatology; it requires differential diagnosis and various surgical tactics. The aim of the study is to present a clinical and radiological picture of post-traumatic patellar tendon ossification in children and its surgical treatment outcomes using a case series as an example. Methods. We present a monocenter retrospective series of 4 male patients. Anamnestic, clinical, radiological and histological data were analyzed. Results. The patients’ mean age was 14 (range, 11-16) years. In all cases, there was a history of trauma. Initially, after getting injured, the patients were treated for a knee injury. In one patient, as a result of his falling on 2 limbs, a bilateral pathology was observed; in other three cases, the pathology was unilateral. Flexion contracture and pain syndrome prevailed in the clinical picture. All patients underwent surgery ranging from excision of ossifications to excision of ossifications with reconstruction of tendon defects and refixation of the tibial tuberosity with osteosynthesis. In all cases, knee joint contracture was eliminated and the volume of movement was fully restored. Histology showed fragments of mature bone tissue represented by thinned bone beams with focal osteoclastic reaction and areas of endochondral ossification. Conclusions. The clinical picture of pediatric patients with patellar tendon ossification manifests in the form of a chronic cascade of symptoms and functional and topographic disorders: patellar tendon ossification, patella alta, anterior knee pain, flexion contracture and rectus femoris muscle hypotrophy. X-ray and MRI data determine a formation of bone density with uneven clear contours in the projection of the patellar tendon, along with patella alta and the Caton-Deschamps index increasing more than 1.3. The primary treatment method of the developed complication is the surgical one, which leads to the restoration of the full amplitude of movements in the knee joint.

The article offers an interdisciplinary approach to the study of digitalization in the sphere of fossil fuel business between XX and XXI centuries. This economic sector has always resisted changes, which makes the research relevant both scientifically and technologically. The authors applied the theory of modernization to analyze the key forms and methods of digitalization as part of the innovative movement in the Russian economy that took place in the early 2000s. The comparative analysis made it possible to identify the patterns behind the economic, scientific, and technical development model, including individual segments and industries. The research revealed the causes and factors that guided the processes of automation, informatization, and computerization in the domestic fuel and energy complex, also in the intersectoral context. The analysis made it possible to describe the role of the state and the business in this process. The digitalization was more active in informatization and computerization. As the scientific and technological leadership passed on from the gas industry to the oil industry, the coal mining failed to achieve technological parity by 2010. The extensive methods of implementing digital solutions, which prevailed in the 1990s and early 2000s, gave way to intensive ones. It took fuel and energy enterprises 20 years to shift from occasional automation, informatization, and computerization to a comprehensive digital transformation. The latter resulted in innovative products in other industries. As Russia’s energy security strengthened, the digital support grew more and more dependent on foreign software and hardware.

One of the most important problems of our time is the annual increase in greenhouse gas emissions into the atmosphere. It is possible to combat this phenomenon by reducing emissions or developing and applying technologies for capturing, storing, using and disposing of CO2. In this work, an assessment of the expediency and possibility of carbon dioxide burial in deep aquifers is considered, the study of which is carried out to a small extent and due to the lack of useful material in them. The parameters and results of CO2 injection into the aquifer of one of the oil fields of the Perm Region, the geological properties and characteristics of which are determined in this work, are studied. The criteria of applicability, methods of estimating the volume of the reservoir and laboratory studies to determine the properties of CO2 and the features of its interaction with the model of the reservoir fluid are considered. The injection object and reservoir volume were determined, PVT studies of the target gas were performed, and its solubility in reservoir water was determined. The duration of filling the full volume of the trap when capturing 400 thousand tons of CO2 per year from the target industrial facility is calculated to be 202 years. This conclusion signals the prospects for the burial of carbon dioxide in the underground deposits of an undeveloped aquifer complex in the Perm Region, which reflects the importance of studying such geological CO2 burial sites in order to achieve global carbon neutrality goals.

There is currently a consensus among the scientific and engineering community regarding the solution to the problem of minor actinides (MAs) formed in the process of nuclear power operation: MAs need to be converted to fission products during burnup in power reactors. Fast neutron reactors (BN, BREST) and molten salt reactors (MSR) are considered largely to this end. Despite the advantages of using fast reactors, there are no currently power unit designs with BN or BREST reactors available for commercial operation. The possibility of using VVER reactors for this purpose is rarely covered in scientific literature, despite the fact that the technology of light water reactors has long been mastered, and preparing a VVER-based MA burner reactor is technically simpler than on the basis of a pilot commercial BN technology or BREST or MSR reactors at different R&D stages. In the previously published first part of the study by Kazansky and Karpovich 2022, the fuel cycle for VVER reactors was investigated: minor actinides obtained during reactor operation were extracted from spent nuclear fuel and added to fresh fuel for the same reactor. It has been found that implementing this cycle and bringing the concentration of MAs up to 4 wt. % makes it possible to reduce the amount of minor actinides produced in the VVER reactor by a factor of 8, and without a loss in the NPP unit power generation. This paper investigates, based on an idea of closing the fuel cycle in terms of minor actinides, the relationship between the MA burnup depth in a VVER-1200 reactor and the enrichment of fresh fuel, the dynamics of unloaded heavy nuclei, and the amount of MAs in additionally loaded fuel. Under investigation are two types of additionally loaded fuel with oxides of minor actinides added to it: based on enriched uranium dioxide or a mixture of (1 – x) 232ThO2+x (96% UO2) (Kazansky et al. 2023). At the same time, the number of heavy nuclei in fuel does not change when there is a change in the number of loaded MA nuclei, which is measured in the number of the VVER-1200 reactors “served” (the mass of accumulated MA nuclei is about 1% and is removed annually from spent fuel). The number of minor actinides entering fuel is kept at a level that allows having a reactivity margin for the reactor operation at a power of over 2% before the annual refueling. Calculations were undertaken using a fuel assembly model with fuel elements broken down into a number of groups with different fuel burnup depths to simulate the actual loading of the reactor core. This model makes it possible to avoid the power peaking effects and give an answer about the neutronic characteristics of the fuel cycle involving MAs. The calculations made it possible to make a number of important conclusions: more refueling cycles lead to a dynamic equilibrium taking place between the minor actinide amounts loaded and burnt; the number of the reactors served is directly proportional to the enrichment of the make-up fuel and a 20% UO2 enrichment makes it possible to serve up to 23 VVER-1200 reactors, while using 80% 232ThO2 + 20% (96% UO2) fuel allows 17 VVER-1200 reactors to be served; using MAs extracted from SNF with a burnup of 20 to 50 MW*day/kg leads to the MA composition effect on the reactivity balance being within 4 to 5 βeff.

Abstract Background Difficulties with speech-in-noise perception in autism spectrum disorders (ASD) may be associated with impaired analysis of speech sounds, such as vowels, which represent the fundamental phoneme constituents of human speech. Vowels elicit early (

Aim. Assessing the effectiveness of new baselines and intensity thresholds of epidemics based on rates of incidence and hospitalization with a diagnosis of “influenza” to clarify the timing of epidemics and their spread throughout the Russian Federation against the backdrop of the COVID-19 pandemic (from 2021 to 2024). Materials and methods. At the A.A. Smorodintsev Influenza Research Institute, the software was reformed taking into account the need to solve the tasks set during the COVID-19 pandemic. Due to changes in influenza surveillance in relation to the diagnosis of “influenza”, and hence the increase in the registration of influenza cases, the baseline and threshold of epidemics were adjusted for the influenza incidence and hospitalization rates in the surveyed cities in total (61) and for each Federal districts (over the entire population and by age groups) for 3 epidemics against the background of COVID-19 pandemic (2021–2022, 2022–2023, and 2023–2024). Results. A comparison of baselines calculated over the previous 6 seasons based on the incidence and hospitalization rates of mostly clinically diagnosed influenza and new baseline levels of incidence and hospitalization rates of mostly laboratory-confirmed influenza during the pandemic showed minor changes in the indicators of baseline incidence and hospitalization rates while epidemic thresholds for these indicators increased. Conclusion. Against the backdrop of the COVID-19 pandemic during the 2020–2021 season, there was no influenza epidemic. In 2021–2022, the A(H3N2) epidemic was of low intensity in terms of incidence, hospitalization rates and low mortality (2 cases). In 2022–2023, the influenza A(H1N1)pdm09 and B epidemic was of moderate intensity in terms of incidence, with a high frequency of hospitalizations and mortality (120 cases). Influenza A(H3N2) and B epidemic in 2023–2024 was of a “very high” level in terms of the influenza incidence, but average in terms of the frequency of hospitalizations and mortality (41 cases), with higher incidence rate compared to the previous epidemic (0.28% and 0.19% of the total population), including persons over 15 years of age (0.19% and 0.12%).

The heterocyclic core of imidazo[1,2-a]pyrimidine was formed in satisfactory yields as a result of the interaction of the readily available 2-aminoimidazole with N-substituted maleimides or N-arylitaconimides. The mechanism of the studied processes was postulated basing on experimental data, HPLC–MS analysis of reaction mixtures, and quantum chemical calculations. Molecular docking results of the obtained imidazo[1,2-a]pyrimidines, when compared with voriconazole, a drug already in clinical use, suggest that they may possess antifungal activity against Candida albicans.

Abstract We study the behavior of static, spherically symmetric solutions to the field equations of scalar–tensor theories (STT) of gravity belonging to the Bergmann–Wagoner–Nordtvedt class, in the presence of an electric and/or magnetic charge. This class of theories includes the Brans–Dicke, Barker and Schwinger STT as well as nonminimally coupled scalar fields with an arbitrary parameter $$\xi $$ ξ . The study is restricted to canonical (nonphantom) versions of the theories and scalar fields without a self-interaction potential. Only radial (monopole) perturbations are considered as the most likely ones to cause an instability. The static background solutions contain naked singularities, but we formulate the boundary conditions in such a way that would preserve their meaning if a singularity is smoothed, for example, due to quantum gravity effects. These boundary conditions look more physical than those used by other authors. Since the solutions of all STT under study are related by conformal transformations, the stability problem for all of them reduces to the same wave equation, but the boundary conditions for perturbations (and sometimes the boundaries themselves) are different in different STT, which affects the stability results. The stability or instability conclusions are obtained for different branches of solutions in the theories under consideration and are presented in a table form.

In the process of developing and operating navigation systems, it is very important to reliably assess the accuracy of determining spatial characteristics. A methodology has been developed for assessing and confirming the accuracy of determining spatial characteristics by various software and hardware systems, such as coordinates, velocity, and orientation. The basis was taken from the foreign standard ASTM E3064-16, which describes coordinates and orientation accuracy confirmation of optical tracking systems. The developed approach is based on assessing the accuracy of measuring a certain fixed length (rod) in different positions and orientations. The speed accuracy assessment is based on the coordinate accuracy assessment and is based on the use of linear regression to calculate the speed. The error in determining the orientation angle in space is also calculated based on the coordinate measurement error and is given for small angles. The applicability limits of the described methodology are given. The technique makes it possible to assess the accuracy and reliability of navigation and measuring systems.

Background. Technological innovations have become an important agent of social change, creating new socio-psychological meaning. In this context, G.M. Andreeva's idea that social psychology should help people adapt to changing environments remains relevant. Objectives. This paper aims to highlight the socio-psychological perspective on the role of innovative technologies in social change. We present two empirical studies that demonstrate emerging socio-psychological patterns in the context of open-source software development (study 1) and the use of virtual assistants (VA) for economic decision-making (study 2). Study Participants. Study (1): 900 posts from a collaborative development platform. Study (2): 200 users of the VA popular in Russia, residents of Russian cities with a population of more than 500,000 people. Methods. Study (1): Content analysis using large language models. Study (2): Quantitative online survey assessed users' perception of their VA and previously unknown VA across 15 characteristics, subjective trust levels, and economic trust through scenarios involving monetary transactions. Results. Study (1): A pre-configured GPT-4 turbo model with an instruction consisting of two examples achieved 56% accuracy in classification. Using a fine-tuned model of the previous generation, DeBERTa-v3-Small, increased the efficiency of classifying developer messages by up to 70%. This allowed the model to be used to encode developer interactions in order to identify the factors that contribute to effective collaboration. Study (2): Both forms of trust (declared and economic) are significantly related to components of social representations (SR) of VA. Individual components of these perceptions correlate with both declared and economic trust at the level of r > 0.3, p < 0.05. However, there is a difference in the strength of these relationships for familiar and unfamiliar VAs. An assumption can be made about the possible influence of the duration of use of VA on the strength of connections between SR and trust in VA. Thus, SR formed through interaction with VA contributes to a trusting attitude towards it and, accordingly, to decision-making processes involving its use. Conclusions. Socio-psychological knowledge about the changing socio-psychological meaning can form the foundation for the development of human-centered technologies. As a part of professional work, a developer can improve current tools for the creation, management, and optimization of collaborative activities. In everyday life, it is also important to establish a level of trust that is appropriate for the situation in which a Virtual Assistant is used.

Abstract GPR179, an orphan class C GPCR, is expressed at the dendritic tips of ON-bipolar cells in the retina. It plays a pivotal role in the initial synaptic transmission of visual signals from photoreceptors, and its deficiency is known to be the cause of complete congenital stationary night blindness. Here, we present the cryo-electron microscopy structure of human GPR179. Notably, the transmembrane domain (TMD) of GPR179 forms a homodimer through the TM1/7 interface with a single inter-protomer disulfide bond, adopting a noncanonical dimerization mode. Furthermore, the TMD dimer exhibits architecture well-suited for the highly curved membrane of the dendritic tip and distinct from the flat membrane arrangement observed in other class C GPCR dimers. Our structure reveals unique structural features of GPR179 TMD, setting it apart from other class C GPCRs. These findings provide a foundation for understanding signal transduction through GPR179 in visual processing and offers insights into the underlying causes of ocular diseases.

Relevance. The need to obtain information about the chemical nature of the resin-asphaltene and oil components of atmospheric residue from distillation of crude oil produced at the Krapivinskoe field in order to select optimal technologies for its rational utilization. Aim. To study the structures of asphaltene macromolecules and resin substances and the molecular composition of the oil components of atmospheric residue from distillation of crude oil produced at the Krapivinskoe field. Methods. Transmission electron microscopy, X-ray phase analysis, IR spectroscopy, 1H NMR spectroscopy, structural group analysis, chemical destruction, gas chromatography-mass spectrometry. Results. The structure of resin-asphaltene substances and the molecular composition of atmospheric residue obtained in the course of atmospheric distillation of oil from the Krapivinskoe field in laboratory conditions have been characterized using a complex of physicochemical research methods. It was found out that asphaltenes of atmospheric residue have a predominantly amorphous structure because of the presence of a developed alkyl chain configuration in their macromolecules. Mean asphaltene molecules consist of three structural blocks, which basis is triarene cores condensed with four to five naphthenic rings. These naphthenoaromatic systems neighbor upon methyl substituents only. The mean molecules of atmospheric residue resins are predominantly single-block. Their structural blocks are more compact due to the smaller number of aromatic and naphthenic rings in the naphthenoaromatic system. A feature of mean resin molecules is also the presence of relatively long alkyl substituents in the blocks. It was established that the structure of asphaltenes and atmospheric residue resins contains fragments linked to each other or to the naphthenoaromatic core of their macromolecules through sulfide and ether bridges. In both types of ‘linked’ fragments, n-alkanes, n-alkylcyclohexanes and hopanes were identified. Among the fragments linked through sulfide bridges, n-alkylbenzenes, n-alkylmethylbenzenes and n-alkanoic acids were additionally identified, while ethyl esters of n-alkanoic acids were identified among fragments linked through ether bridges. A structural feature of the atmospheric residue resins is the presence of phenylalkanes with different positions of the phenyl substituent in both types of bridge-linked compounds. Steranes and phenanthrenes are present in the composition of compounds linked through sulfide bridges. The oil components of atmospheric residue contain n-alkanes, n-alkylcyclohexanes, hopanes, steranes, n-alkylbenzenes, n-alkylmethylbenzenes, alkylnaphthalenes and alkylphenanthrenes.

Foreword to the virtual focused issue of Journal of Synchrotron Radiation on X-ray spectroscopy to understand functional materials: instrumentation, applications, data analysis.

Abstract Many neurotransmitter receptors activate G proteins through exchange of GDP for GTP. The intermediate nucleotide-free state has eluded characterization, due largely to its inherent instability. Here we characterize a G protein variant associated with a rare neurological disorder in humans. Gαo K46E has a charge reversal that clashes with the phosphate groups of GDP and GTP. As anticipated, the purified protein binds poorly to guanine nucleotides yet retains wild-type affinity for G protein βγ subunits. In cells with physiological concentrations of nucleotide, Gαo K46E forms a stable complex with receptors and Gβγ, impeding effector activation. Further, we demonstrate that the mutant can be easily purified in complex with dopamine-bound D2 receptors, and use cryo-electron microscopy to determine the structure, including both domains of Gαo, without nucleotide or stabilizing nanobodies. These findings reveal the molecular basis for the first committed step of G protein activation, establish a mechanistic basis for a neurological disorder, provide a simplified strategy to determine receptor-G protein structures, and a method to detect high affinity agonist binding in cells.

Abstract Non-coding RNA expression has shown to have cell type-specificity. The regulatory characteristics of these molecules are impacted by changes in their expression levels. We performed next-generation sequencing and examined small RNA-seq data obtained from 6 different types of blood cells separated by fluorescence-activated cell sorting of severe COVID−19 patients and healthy control donors. In addition to examining the behavior of piRNA in the blood cells of severe SARS-CoV−2 infected patients, our aim was to present a distinct piRNA differential expression portrait for each separate cell type. We observed that depending on the type of cell, different sorted control cells (erythrocytes, monocytes, lymphocytes, eosinophils, basophils, and neutrophils) have altering piRNA expression patterns. After analyzing the expression of piRNAs in each set of sorted cells from patients with severe COVID−19, we observed 3 significantly elevated piRNAs - piR−33,123, piR−34,765, piR−43,768 and 9 downregulated piRNAs in erythrocytes. In lymphocytes, all 19 piRNAs were upregulated. Monocytes were presented with a larger amount of statistically significant piRNA, 5 upregulated (piR−49039 piR−31623, piR−37213, piR−44721, piR−44720) and 35 downregulated. It has been previously shown that piR−31,623 has been associated with respiratory syncytial virus infection, and taking in account the major role of piRNA in transposon silencing, we presume that the differential expression patterns which we observed could be a signal of indirect antiviral activity or a specific antiviral cell state. Additionally, in lymphocytes, all 19 piRNAs were upregulated.

The study focuses on the investigation of the process of forming the motivational aspect of the professional competency of cadets at a maritime university in a blended learning environment. Given the digitalization of higher education and the specific requirements of the maritime industry, there is a need to provide a solution in response to the demands of ship owners. Employers seek to employ motivated young professionals who are not only skilled in their field but also possess a drive for professional growth. The aim of professional training is to develop competencies, while the motivational element remains unaddressed. It is essential to develop techniques that facilitate the development of this aspect. Professiographic monitoring represents a relatively underexplored technique. The objective of this study is to devise and validate the feasibility of utilizing this approach within a maritime university context. The model for the development of the motivational aspect of professional competence has been created and tested. This model defines the role and components of professiographic monitoring. Its functions have been proposed and criteria for assessing the level of motivation in professional competence have been defined. The results of the study demonstrated positive trends in the development of motivation among cadets, indicating a positive impact on their professional competence.

Introduction. Bats are natural reservoirs of coronaviruses (Coronaviridae), which have caused three outbreaks of human disease SARS, MERS and COVID-19 or SARS-2 over the past decade. The purpose of the work is to study the diversity of coronaviruses among bats inhabiting the foothills and mountainous areas of the Republics of Dagestan, Altai and the Kemerovo region. Materials and methods. Samples of bat oral swabs and feces were tested for the presence of coronavirus RNA by reverse transcription-polymerase chain reaction (RT-PCR). Results. It has been shown that the greater horseshoe bats (Rhinolophus ferrumequinum), inhabiting the Republic of Dagestan, are carriers of two different coronaviruses. One of the two coronaviruses is a member of the Sarbecovius subgenus of the Betacoronavirus genus, which includes the causative agents of SARS and COVID-19. The second coronavirus is assigned to the Decacovirus subgenus of the Alphacoronavirus genus and is most similar to viruses identified among Rhinolophus spp. from European and Middle Eastern countries. In the Altai Republic and Kemerovo region, coronaviruses belonging to the genus Alphacoronavirus, subgenus Pedacovirus, were found in the smooth-nosed bats: Ikonnikov`s bat (Myotis ikonnikovi) and the eastern bat (Myotis petax). The virus from the Altai Republic from M. ikonnikovi is close to viruses from Japan and Korea, as well as viruses from Myotis spp. from European countries. The virus from the Kemerovo region from M. petax groups with coronaviruses from Myotis spp. from Asian countries and is significantly different from coronaviruses previously discovered in the same natural host.

Abstract Chaun Bay, located on the fringe of the East Siberian Sea, has been described since the mid-20th century to support a unique marine ecosystem that is atypical for the local Siberian Arctic. Here we use ship-board physical, biogeochemical and geological measurements taken in October 2020, along with hydrographic observations taken from land-fast ice in April 2023, to demonstrate that these warm-water biological communities are supported by hydrothermal submarine groundwater discharge that delivers heat, salinity, nutrients, and trace elements to the bay. We identify a cyclonic eddy that mixes the warm nutrient-rich groundwater with oxygen-rich surface water, resulting in a water mass within Chaun Bay that has similar physical and chemical properties to the highly productive waters of the North Pacific and Southern Chukchi Sea. The bay showed elevated concentrations of chlorophyll-a and zooplankton, and the abundance and species diversity of epibenthos significantly exceeded values observed elsewhere in the East Siberian Sea. The benthic communities contained a number of boreal species that are not typically found in the Arctic Ocean. We also observed Thysanoessa krill populations, a pelagic species generally considered an expatriate in Arctic waters.

Introduction. The traditional surveillance system for influenza and ARVI provides a general description of epidemics, but does not provide information on the age-related characteristics of the etiology and clinical peculiarities of severe acute respiratory diseases (SARI) in hospitalized patients. Aim. To monitor the etiology of SARI in hospitalized children and adults, assessing the impact of the COVID-19 pandemic on this process. Materials and methods. Standardized clinical and laboratory monitoring of SARI among 18,458 hospitalized patients was carried out in hospitals in three cities of Russia with weekly PCR detection of 11 types of pathogens. Results. According to the investigation of hospitalized patients with SARI for the period from 2018 to 2023, the viral etiology of respiratory diseases was deciphered in 58.3% of cases. Weekly monitoring showed a change in the etiological mosaic of SARI pathogens during the SARS-CoV-2 pandemic with a sharp decrease in the frequency of detection of influenza and respiratory syncytial virus (RSV) during the 2020–2021 season against the background of a significant increase of metapneumovirus and rhinovirus infections in children. During the 2022-2023 season an increase in the proportion of RSV infection in children under 6 years of age (up to 36.2%) was noted against the background of a significant decrease in the frequency of SARS-CoV-2. In the intensive care units (ICU), RSV infection was most often in children during the post-pandemic period (up to 30.1–53.6% of positive cases, p 0.001); in adults, SARS-CoV-2 was mostly detected (76,5–100% of cases, p 0.001). Conclusion. Hospital surveillance data significantly complements the epidemiological information obtained in the traditional surveillance system. Monitoring of infections has shown a continuously changing etiological infrastructure of SARI, with the disappearance of influenza and RSV during the COVID-19 pandemic and their return to circulation in the post-pandemic period.

Abstract One of the main issues in gravitation is the presence of singularities in the most common space-time solutions of General Relativity, as the case of black holes. A way of constructing regular solutions that remove spacelike singularities consists in implement a bounce on such space-time, leading to what is usually known as black bounce space-times. Such space-times are known to describe regular black holes or traversable wormholes. However, one of the main issues lies on reconstructing the appropriate source that leads to such a solution. In this paper, a reconstruction method is implemented to show that such types of metrics can be well accommodated in non-linear electrodynamics with the presence of a scalar field. Some of the most important black bounces solutions are reconstructed in this framework, both in 3 + 1 as in 2 + 1 dimensions. For the first time in the literature, these solutions have an electrically charged source of matter from non-linear electrodynamics. Specific features are indicated that distinguish electric sources from magnetic ones, previously found for the same space-times.

Abstract The ability to finely tune the properties of magnetic topological insulators (TIs) is crucial for quantum electronics. We studied solid solutions with a general formula GexMn1-xBi2Te4 between two isostructural Z2 TIs, magnetic MnBi2Te4 and nonmagnetic GeBi2Te4 with Z2 invariants of 1;000 and 1;001, respectively. We observed linear x-dependent magnetic properties, composition-independent pairwise exchange interactions, and topological phase transitions (TPTs) between topologically nontrivial phases and the semimetal state. The TPTs are driven purely by the variation of orbital contributions. By tracing the x-dependent Bi 6p contribution to the states near the fundamental gap, the effective spin-orbit coupling variation is extracted. The gapless state observed at x = 0.42 closely resembles a Dirac semimetal above the Néel temperature and shows a magnetic gap below, which is clearly visible in raw photoemission data. The observed behavior demonstrates an ability to precisely control topological and magnetic properties of TIs.

Abstract Understanding spin-lattice interactions in antiferromagnets is a critical element of the fields of antiferromagnetic spintronics and magnonics. Recently, coherent nonlinear phonon dynamics mediated by a magnon state were discovered in an antiferromagnet. Here, we suggest that a strongly coupled two-magnon-one phonon state in this prototypical system opens a novel pathway to coherently control magnon-phonon dynamics. Utilizing intense narrow-band terahertz (THz) pulses and tunable magnetic fields up to μ 0 H ext = 7 T, we experimentally realize the conditions of magnon-phonon Fermi resonance in antiferromagnetic CoF2. These conditions imply that both the spin and the lattice anharmonicities harvest energy from the transfer between the subsystems if the magnon eigenfrequency f m is half the frequency of the phonon 2f m = f ph. Performing THz pump-infrared probe spectroscopy in conjunction with simulations, we explore the coupled magnon-phonon dynamics in the vicinity of the Fermi-resonance and reveal the corresponding fingerprints of nonlinear interaction facilitating energy exchange between these subsystems.

The availability of unmanned aerial vehicles (UAVs) has led to a significant increase in the number of offenses involving their use. This makes the development of UAV detection systems relevant. Solutions based on deep neural networks show the best results in detecting UAVs on video. This article presents a study of various neural network detectors and focuses on identifying objects as small as possible, up to the size of $4\times4$ and even $3\times3$ pixels. The work investigates architectures SSD (VGG16) and YOLOv3 and it's modifications. Precision and recall metrics are calculated separately for different intervals of the object areas. The best result have been shown by YOLOv3 model with bbox parameters chosen as the result of object sizes clustering. Small ($3\times3$ px) drones have been successfully identified with 76% precision and a very small recall of 26%. For objects between 10 and 20 pixels in area, the recall is 64% with an accuracy of 75%. For objects with an area more than 20px the recall is about 90%, the precision is 89%, and the F1 score is 90%. These results show that it is possible to recognize even $4\times4$ pixel drones, which can be used in video surveillance systems.

Relevance. While performing the operation processes, the technological equipment emits vibration. Vibration is a consequence of increased dynamic loads in structural elements and interfaces between systems and their elements. The development of fatigue damage can significantly accelerate. Therefore, the solution of the problems related to reducing vibration levels is always relevant. Each type of protective system has a linear law of changing the stiffness. This does not allow the effective damping of low-frequency vibrations. Thus, the information review demonstrates the future of the research according to the creation of the vibration protection systems, constantly improving their parameters in the following aspects: minimizing overall dimensions and number of parts; increasing reliability, especially in resonant mode; providing the ability to operate in modes with low stiffness. The last factor determines the good damping of vibration emitted by the source. Aim. To study the possibility of the vibration protection system development with quasi-zero stiffness with the ability to effectively dampen low-frequency vibrations. Methods. Information and analytical review in the field of the research, search for the constructive solutions, preliminary design calculations and 3D modeling, description of the device being developed and its operating principles. Results. The research presents the results of development of the vibration protection system with quasi-zero stiffness and a fragment of an information review of existing vibration protection systems. The authors indicated the main shortcomings specific to all vibration protection systems: relatively large sizes, large number of elements, insufficient operating frequency range. The authors proposed a constructive solution for creating a vibration damping system with a nonlinear law of change in stiffness. This solution allows eliminating the above shortcomings and providing the possibility of effective damping of low-frequency vibrations. The authors created the method for calculating the constructive parameters of a vibration damping system. An example of calculation is given in the paper. This system differs from existing vibration protection devices in its low stiffness and small dimensions, and a wide operating frequency range of vibration damping. The efficiency of the system operating with nonlinear and quasi-zero stiffness is proved.

Abstract The increasing accessibility of commercial and private space travel necessitates a profound understanding of its impact on human health. The NASA Open Science Data Repository (OSDR) provides transparent and FAIR access to biological studies, notably the SpaceX Inspiration4 (I4) mission, which amassed extensive data from civilian astronauts. This dataset encompasses omics and clinical assays, facilitating comprehensive research on space-induced biological responses. These data allow for multi-modal, longitudinal assessments, bridging the gap between human and model organism studies. Crucially, community-driven data standards established by NASA’s OSDR Analysis Working Groups empower artificial intelligence and machine learning to glean invaluable insights, guiding future mission planning and health risk mitigation. This article presents a concise guide to access and analyze I4 data in OSDR, including programmatic access through GLOpenAPI. This pioneering effort establishes a precedent for post-mission health monitoring programs within space agencies, propelling research in the burgeoning field of commercial space travel’s impact on human physiology.

Background. Tick-borne bacterial and protozoal pathogens pose a significant public health problem. The aim of this study was to detect and genotype Borrelia, Rickettsia and Anaplasma in Ixodes ricinus and Dermacentor reticulatus ticks collected in the Kaliningrad region in 2021–2022. Materials and methods. The study included 862 I. ricinus and 803 D. reticulatus ticks (1665 in total) collected in 33 biotopes of the Kaliningrad region. Detection of the DNA of tick-borne pathogens was carried out in individual ticks by PCR using a set of specific primers, followed by sequencing and phylogenetic analysis. Results. The level of infection of I. ricinus ticks with Borrelia was 15.5%, and genotyping by the p66 gene sequence showed the presence of genetic material from four species: B. afzelii, B. garinii, B. valaisiana, and B. lusitaniae. In D. reticulatus ticks, no Borrelia genetic material was detected. The Rickettsia DNA has been found in both tick species. Moreover, the infection rate of I. ricinus ticks was 2.6%, and D. reticulatus — 21.2%. R. helvetica were found in I. ricinus ticks, and R. raoultii in meadow ticks when genotyping by gltA gene. Genetic markers of Anaplasma phagocytophilum have been found in I. ricinus and D. reticulatus ticks. Cases of co-infection of an individual tick have also been identified. Conclusion. Six different species of tick-borne pathogens were found in the I. ricinus and D. reticulatus ticks collected in the Kaliningrad region and R. helvetica, R. raoultii and A. phagocytophilum were identified for the first time.

Background: Complex graft bioengineering is an actual topic in bone defects’ repair. For those, different scaffolds may be seeded with mesenchymal stromal cells and growth / differentiation factors. The natural role of platelet factors in reparative processes justifies the possibility of its usage for mesenchymal stromal cell proliferation and differentiation into osteoblasts in vitro in terms of the scaffold-based bioengineering. To develop and evaluate in vitro biocompatibility and osteoconductivity of a complex biograft based on a bioorganic scaffold seeded with human bone marrow mesenchymal stromal cells and saturated with growth and differentiation factors of allogeneic platelet-rich plasma. Results: The properties of viability and adhesion of human bone marrow mesenchymal stromal cells in four types of bioorganic scaffolds were evaluated with biochemical and immunomorphological methods. Scaffold with the least cytotoxicity was used as a basis for complex biograft formation, so as a carrier for cells and platelet-derived factors. Then, cell proliferation activity and osteogenic differentiation were estimated with biochemical, morphological, histochemical and molecular-biological methods. The study showed high viability of cells in all bioorganic scaffolds but the least cytotoxicity was the one based on xenogeneic collagen sponge. We also found that allogeneic platelet-rich plasma positively affects the proliferation and osteogenic differentiation of bone marrow mesenchymal stromal cells in a complex biograft in vitro. Conclusions: The properties of the developed complex biograft characterize its biocompatibility and osteoconductivity and make it potentially suitable for regenerative medicine, particularly for reconstructive surgery of bone defects.How to cite: Danilkovich NN, Kosmacheva SM, Ionova AG, et al. Formation of osteoconductive biograft with bioorganic scaffold, human mesenchymal stromal cells, and platelet rich plasma with its evaluationin vitro. Electron J Biotechnol 2024;69. https://doi.org/10.1016/j.ejbt.2024.01.004.

Aim – to evaluate the effectiveness of vaccination when using various vaccines against COVID-19 approved for use in Russia among medical staff and faculty of medical higher educational institutions according to online questionnaires. Material and methods. A cross-sectional study was conducted online from January to March 2022 (circulation period of the omicron genovariant). The survey was completed by 6032 respondents, 2114 respondents were excluded from the study. The remaining 3918 respondents were included in the the analysis. Results. 47 (0.1%) medical workers reported COVID-19 incidence within 21 days after the second dose of the vaccine. 616 (16.8%) medical workers reported COVID-19 incidence within 5 months after two vaccinations. 116 (46.4%) unvaccinated respondents reported a laboratory-confirmed new coronavirus infection within 5 months prior to the survey. Lack of vaccination increased the risk of SARS-CoV-2, OR 1.78 ± 0.14 (95% CI 1.34-2.36). It was found that gender and age were not a risk factor for the onset of the disease in the post-vaccination period. The presence of SARS-CoV-2 in medical history increased the risk of developing the disease in the post-vaccination period. Conclusion. The analysis revealed that vaccination had significantly higher protection effect for 1.5 months after vaccination and significantly reduced in 5 months after vaccination.

The study examines the key features and areas of the Bharatiya Janata Party (BJP) government’s policy aimed at boosting the export of weapons, military and special equipment (WMSE) within the broader strategy of reforming the Indian military-industrial complex (MIC). The long-term goal of the Indian government is to achieve “strategic autonomy” in the defence sector. In the short term, Indian arms exports serve as the driving force behind the “Make in India” and “Self-reliant India” programmes - pivotal components of Prime Minister Modi’s political agenda. The significant amplification factor for India’s export ambitions has been conditioned in part by the escalating border tensions with China since 2017. The export of WMSE is emerging as a crucial tool to strengthen India’s bilateral relations with countries in the Asia-Pacific region to counterbalance China. Nonetheless, to propel India into the group of the world’s leading arms exporters, as well as to gain full “strategic independence,” may be hard to achieve even in the long run. Despite systemic reforms in the military-industrial complex, efforts to engage private businesses and attract foreign capital, a number of challenges impede the growth of the defence industry and the export potential of the Indian military-industrial complex. These include the inadequate development of India’s manufacturing sector, dependency on foreign technologies, and insufficient funding for military-technical advancements. At the same time, the policy of supporting defence exports and reforming the MIC has been a stable trend in the strategy of the BJP government, playing a crucial role in the fulfillment of its short, medium and long term goals.

Introduction. A very common technology of pedigree seed production is associated with manual in-process transshipment of many sacks that over time results in damaged sacks and in worsening of grain storage conditions. In this regard, there is a need to design a multifunctional rigid container, which will provide cost-effective storage of seed grain through the airtightness and control of the indoor environment. Aim of the Study. The study is aimed at designing a multifunctional container for primary seed production of grain crops with justification according to the criteria of technical and economic efficiency in comparison with pallet spaces and sacks. Materials and Methods. The state standard for economic evaluation of agricultural machinery was applied to assess the impact of reducing in-process transshipment of many sacks and seed losses in primary seed production of grain crops. Wheat seeds were used as the seed-producing crop under study. As service equipment there were used Wintersteiger Delta plot combine with a cutterbar working width of 2 m, seed bagging system or grain hopper 1.5 m3, Belarus 622 tractor with 1PTS-2 semi-trailer, TOR CD1 10916 electric telpher, and convective grain drying units on the basis of SL-0.3x 2 tray dryer for grain. Results. The authors of the article have estimated the technical and economic efficiency of using sacks and multifunctional containers in technological operations of harvesting, transporting and drying grain. With the annual notional volume of work in 400.7 tons, the saving of total money costs for a plot seed combine-harvester averages 117.9 thousand rubles. The reduction in the cost of work performance is 32.8%, payback period is 2 years; the decrease in the need for service personnel and harvesters is not revealed. At the same time, the reduction in the need for energy sources is 32.3%. Discussion and Conclusion. It has been determined that during technological operations of harvesting, transporting and drying, the best seed production performance is when using the multifunctional container with the following indicators of specific cargo turnover, p: Ui = 800 t/km2; Lг = 0.15 km; b = 0.01 km; Lп‒т = 0.5 km, initial humidity of seeds is 21%. In the process of using this container, the production cost, need for service personnel, energy sources and machinery are reduced.

The article considers the relationship between the financial technologies development and sustainable development indicators on the example of emerging markets’ companies. While environmental, social and corporate governance attracts significant attention in discussions about corporate sustainability, its implementation depends on the development of financial technologies. The mechanisms by which the fintech development affects corporate sustainability indicators in emerging economies remain relatively unexplored. The necessity to understand how the development of financial technologies affects the corporate spheres of ESG reinforces the relevance of the research since it is of great importance for the formation of effective sustainable development strategies. The study uses a comprehensive methodological approach, which includes analysis of data on companies’ financial performance and assessment of the fintech development level in various regions, as well as analysis of its impact on sustainable development corporate indicators. The author uses statistical methods of analysis and mathematical models, as well as comparative studies to obtain more accurate and objective data. The results indicate an obvious relationship: companies operating under less financial constraints demonstrate noticeably higher indicators of sustainable development, especially in regions with developed fintech ecosystems. The research provides a detailed understanding of how the use of fintech can contribute to improving the indicators of sustainable development in emerging markets’ companies. The scientific novelty of the study lies in its in-depth analysis of the factors driving the corporate sustainability development under the influence of fintech technologies, which expands the understanding of the fintech impact on corporate sustainability indicators and opens up new prospects for future research in this area.

Human Immunodeficiency Virus (HIV) proviral reservoirs are cells that harbor integrated HIV proviral DNA within their nuclear genomes. These cells form a heterogeneous group, represented by peripheral blood mononuclear cells (PBMCs), tissue-resident lymphoid and monocytic cells, and glial cells of the central nervous system. The importance of studying the properties of proviral reservoirs is connected with the inaccessibility of integrated HIV proviral DNA for modern anti-retroviral therapies (ARTs) that block virus reproduction. If treatment is not effective enough or is interrupted, the proviral reservoir can reactivate. Early initiation of ART improves the prognosis of the course of HIV infection, which is explained by the reduction in the proviral reservoir pool observed in the early stages of the disease. Different HIV subtypes present differences in the number of latent reservoirs, as determined by structural and functional differences. Unique signatures of patients with HIV, such as elite controllers, have control over viral replication and can be said to have achieved a functional cure for HIV infection. Uncovering the causes of this phenomenon will bring humanity closer to curing HIV infection, potential approaches to which include stem cell transplantation, clustered regularly interspaced short palindromic repeats (CRISPR)/cas9, “Shock and kill”, “Block and lock”, and the application of broad-spectrum neutralizing antibodies (bNAbs).

Rhinoviruses and respiratory enteroviruses remain among the leading causes of acute respiratory infections, particularly in children. Little is known about the genetic diversity of enteroviruses and rhinoviruses in pediatric patients with acute respiratory infections in Russia. We assessed the prevalence of human rhinoviruses/enteroviruses (HRV/EV) in 1992 children aged 0 to 17 years hospitalized with acute respiratory infections during the 2023–2024 epidemic season using PCR. The detection rate of HRV/EV was 11% (220/1992). We performed typing of 58 HRV and 28 EV viruses by partial sequencing of the VP1 gene. Rhinovirus A was the most common among HRV, followed by rhinovirus C; rhinovirus B was detected in only three cases. Enteroviruses were represented by all four species, with the EV-D68 genotype being the most frequently detected. Phylogenetic analysis of the VP1 fragment of EV-D68 showed that all our sequences belonged to the B3 subclade. We identified the first case of EV-C105 infection in Russia in a two-year-old girl hospitalized with pneumonia. Phylogenetically, the Novosibirsk strain EV-C105 was closely related to a strain discovered in France in 2018. This research helped to fill a critical gap in understanding the epidemiological landscape of HRV/EV in pediatric populations within Russia.

Relevance. The need to determine the permissible errors of hydraulic calculations of surface pipelines of the reservoir pressure maintenance system. This must be done, among other things, due to changes in the properties of produced water. As a result of the transition of most fields to the late stages of development, the water content of the extracted products increases, the composition and properties of reservoir waters change due to the breakthrough of the injected water. These circumstances can lead to significant changes in the mineralization, composition and Ph of water, which must be taken into account in numerical modeling. Aim. Creation of a nomogram for estimating the error in the course of changing the properties of produced water for numerical modeling of the operation of pressure pipelines of the reservoir pressure maintenance system. Methods. Hydraulic calculations in the engineering process simulator software, analysis of the properties of produced water samples in the laboratory, assessment of the density of produced water samples in the PVTSim 20 software product. Results. The studies were carried out on samples of produced water taken from seven wells. The value of salinity in the reservoir pressure maintenance system during the year varies from 247.85 to 327.79 g/dm3. The calculated density varies from 1188 to 1255 kg/m3. To calculate the pressure at the mouth of the injection well during water injection, samples with the highest, average and lowest density were taken. Analyzing the obtained data, a strong effect of water properties on the values of wellhead pressures is noticeable. On the basis of the conducted studies, a nomogram was created to determine the degree of influence of changes in water properties in the course of hydraulic calculation, taking into account the specific-injectivity index of injection wells and the length of pipelines. Conclusion. In the course of numerical modeling, it is quite difficult to take into account all the parameters that affect the accuracy of the calculations obtained. To do this, it is proposed to use the created nomogram, which allows estimating the permissible errors of hydraulic calculation taking into account the variability of the properties of water sent to the reservoir pressure maintenance system.

Background Ceramic materials are currently in wide demand in various fields of medicine. Zirconium ceramics demonstrate exceptional mechanical properties and biocompatibility and do not cause cytotoxic effects or allergic reactions in surrounding tissues. The objective was to present an analysis of current literature data on the use of zirconium ceramics as a bone replacement material in traumatology and orthopaedics. Materials and methods The search for publications was conducted using the databases of Scopus, PubMed and the electronic scientific library eLIBRARY in the Russian and English languages using the keywords: bioceramics, bone, bone defect, zirconate, zirconium ceramics, bone tissue engineering, implant, scaffold, augment, biointegration, bioactivity. Depth of search for scientific papers was from 2000 to 2023. Results and discussion Zirconium dioxide is the main ceramic bioinert material. The study presents the characteristics of ZrO2 as a bone replacement material and its comparison with titanium implants. Data are presented on various strategies for improving zirconium bioceramics: improving the surface of the material by physical and chemical methods, obtaining volumetric porosity, including using additive technologies, creating composite materials, and developing bioactive coatings. New methods of creating zirconium ceramics compatible with living tissues containing bioactive ions that promote both osseointegration and bone tissue regeneration have been actively studied. Conclusions Zirconium dioxide ceramics appear to be a promising alternative to titanium implants in terms of mechanical strength, biological functionality, chemical stability, osseointegration, and antibacterial properties. Future experimental and clinical studies will further improve zirconium ceramics.

The results of experimental studies based on the analysis of deposited coatings and processing methods aimed at reducing the number of non-metallic inclusions in the process of laser powder cladding are presented. The main purpose of the experiments was to determine the effectiveness of various methods for reducing non-metallic inclusions in deposited coatings. The source of such defects are often oxides and slag on the treated surface, as well as granules of powder material used for applying wear-resistant coatings. Corrosion-resistant heat-resistant steel of the 08X18N10T grade (analog AISI 321) was used as the substrate material, from which samples with dimensions of 100x100x8 mm were made. Cladding was performed using a metallic powder 08Kh17N8S6G (analog of the TSN-6L electrode) with a fractional composition of 63-125 microns, having a spherical particle shape and having good fluidity. Experimental laser cladding was carried out on a laser robotic complex based on an ytterbium fiber laser. Evaluation of nonmetallic inclusions was carried out by metallographic analysis on etched cross-sections of the resulting deposited coatings, as well as by RAMAN spectroscopy. The qualitative dependence of the content of defects, such as gas pores, in the layer of the deposited coating on the crystallization of the melt bath formed during laser powder cladding has been established.

The results of the development of a high-voltage semiconductor voltage generator (based on IGBT transistors) with a pulse transformer and the results of experiments on generating a capillary discharge using it on a compact gas-discharge source capable of generating pulses of soft X-ray radiation (SXR) in the area of the socalled «water window» - with wavelength in the range of 2.4...4.4 nm. Methods for designing a high-voltage pulse voltage pulse generator are described: theoretical calculations and results of modeling the electrical circuit diagram in the LTSpice software package, the developed design of a pulse transformer based on N87 ring ferrites and the generator itself is described, the results of its operation as part of a compact gas-discharge radiation source are presented and analyzed. The prospects of using such a high-voltage generator (with semiconductor transistor switches) with a pulse transformer as part of a soft X-ray radiation source are shown due to its technical and operational features: the developed generator is capable of operating from an alternating current network of 380 V/50 Hz in a frequency-burst mode (with a repetition rate of the generated voltage pulses up to 600 Hz) and charges the capillary capacitance of the SXR source to a voltage of more than 20 kV in a time of about 4 μs, has small dimensions, does not create pulsed high-frequency interference and false alarms, and also has stable output (amplitude-temporary) parameters.

It is difficult to imagine modern mechanical engineering without timely and targeted improvement of technological processes, in connection with which new and enhanced traditional methods of manufacturing and processing various types of structures and parts are being developed. One of the ways to reduce the economic costs of machining gears made by traditional methods is the transition to the field of powder metallurgy - powder sintering. This paper presents the possibility of a local increase in the mechanical properties of gears made by powder sintering using laser processing. Laser processing was carried out on a robotic welding and heat strengthening complex, which includes a 6-axis industrial robot, a 2-axis welding positioner, a laser head and a 5 kV ytterbium fiber laser. The high porosity of the sintered material compared to cast billets is a factor limiting the possibility of using laser thermal hardening, as it increases the likelihood of melting the edges of the machined surfaces. The present work is aimed at solving this problem. Before carrying out the experiments, the main quality criteria were identified: “no melting” and “hardening depth”. In the course of a series of experiments on laser thermal hardening, it was possible to significantly increase the hardness of the samples (in the delivered state about 30 HRC), which after processing is in the range from 55 to 65 HRC with a depth of up to 2800 μm on gear teeth made of powder materials. However, open questions remain, which are resolved in performance testing, such as durability and wear.

The paper studies the Al–Mg–Si alloy that does not contain scandium and zirconium, as well as the silicon-rich Al–Mg–Si–Sc–Zr alloy. Multistage thermal treatment was carried out for the Al0.3Mg1Si0.3Sc0.15Zr alloy, which included annealing at a temperature of 440 °C for 8 h, high-temperature annealing at 500 °C for 0.5 h, and artificial aging at a temperature of 180 °C with soaking for 5 h. The Al0.3Mg1Si alloy was annealed at 550 °C for 8 h, and then artificial aging was carried out similarly to the alloy with Sc and Zr additives. To study the fine structure, transmission electron microscopy was used. In the as-cast condition and after each stage of thermal treatment, the mechanical properties of the alloys were determined. It has been found that in an alloy doped with Sc and Zr, the formation of Al3Sc particles occurs already at the stage of formation of the cast structure. During subsequent artificial aging, the supersaturated solid solution decomposes with the formation of β" (Mg5Si6) particles improving mechanical properties. It has been found that in the scandium-containing alloy, fewer β" (Mg5Si6) particles are formed, as a result of which its strength properties are slightly worse than those of the base alloy are. Moreover, these particles are larger than in an alloy that does not contain scandium. This is explained by the fact that complete quenching is impossible for an alloy with scandium additives.

The paper deals with assessing the effects of the ENDF/B-VI.8, ENDF/B-VII.0, JEFF 3.1 and JEFF 3.1.1 nuclear data libraries on the results of calculating a number of functionals for a system based on a VVER reactor with fuel with a large fraction of minor actinides (up to 10%). Key estimates have been obtained for the errors introduced by libraries in calculations of systems with minor actinides (MA) based on a VVER-1200 reactor: – for reactivity, σρ = 0.3 βeff; – for isotopic compositions with minor actinides, ≤ 5% (the error for each particular isotope is different); – for the total mass of accumulated MAs, εm = 0.8%. Conclusions have been made with respect to the need for the further refinement of the library MA data proceeding from the nature of the calculation tasks that dictate the requirements for the accuracy of nuclear constants. It has been shown that systems based on VVER-1000/1200/1300 reactors with MAs need to be calculated using several libraries of evaluated nuclear data created at different organizations and based on the largest possible number of non-recurrent sets of experimental data.

The effect of the Mn3+ ion on the local distortions of FeO6 octahedra in orthoferrite samples was investigated. Mössbauer spectroscopy measurements for a series of HoFe1−xMnxO3 (x = 0–0.7) orthoferrite samples with the space group Pnma were carried out at temperatures above the Néel point (700 K). The electric field gradient (EFG) tensor on Fe ions for these compounds was found using first-principle calculations. The concentration dependence of quadrupole splitting was obtained using experimental and theoretical data. Mn3+ cations were found to affect the Mössbauer spectra mainly due to distortions of the crystal lattice. Theoretical calculations show that the values of all electric field gradient components increase significantly with the manganese concentration in the system, and the eigenvectors exx and eyy of the electric field gradient tensor sharply change their direction at concentrations of x > 0.1.

tRNA-derived fragments function as markers in addition to playing the key role of signalling molecules in a number of disorders. It is known that the repertoire of these molecules differs greatly in different cell types and varies depending on the physiological condition. The aim of our research was to compare the pattern of tRF expression in the main blood cell types and to determine how the composition of these molecules changes during COVID-19-induced cytokine storms. Erythrocytes, monocytes, lymphocytes, neutrophils, basophils and eosinophils from control donors and patients with severe COVID-19 were obtained by fluorescence sorting. We extracted RNA from FACS-sorted cells and performed NGS of short RNAs. The composition of tRNA-derived fragments was analysed by applying a semi-custom bioinformatic pipeline. In this study, we assessed the length and type distribution of tRFs and reported the 150 most prevalent tRF sequences across all cell types. Additionally, we demonstrated a significant (p < 0.05, fold change >16) change in the pattern of tRFs in erythrocytes (21 downregulated, 12 upregulated), monocytes (53 downregulated, 38 upregulated) and lymphocytes (49 upregulated) in patients with severe COVID-19. Thus, different blood cell types exhibit a significant variety of tRFs and react to the cytokine storm by dramatically changing their differential expression patterns. We suppose that the observed phenomenon occurs due to the regulation of nucleotide modifications and alterations in activity of various Rnases.

Bufo verrucosissimus is an endangered species in the Russian Federation. One of the largest protected areas where B. verrucosissimus is preserved is the Caucasian State Nature Biosphere Reserve. The paper presents data on age structure and growth of B. verrucosissimus collected in the Caucasian State Nature Biosphere Reserve in 1987–1990 and stored in the collection of Sochi National Park. The age of 16 females and 51 males was determined using the method of skeletochronology. The age of adult females was 6–10 years (on average 7.9 years), and males 2–9 years (on average 5.8 years). Females were statistically significantly superior to males in average age. In terms of body length, significant differences between males and females where noted in groups of seven- and ten-year-old animals. The body length of studied animals (60.8–116.4 mm for females and 61.2–86.3 mm for males) corresponds to the size of adult toads from other localities in the North Caucasus. Females grow evenly throughout their lives, while the growth of males slows down significantly after reaching puberty. Males were able to reach the maximum body length faster than females (the growth coefficient was 0.722 for males and 0.163 for females). According to the von Bertalanffy equation, the maximum possible body length was 130.9 mm for females and 74.6 mm for males.

The aim of the study is assess the reliability, internal stability and effectiveness of adaptation of individual questions of the QAA-25 questionnaire to assess the potential adherence to treatment of persons aged 12–14 years, in comparison with a similar QAA-25 questionnaire for persons aged 15–17 years. Material and Methods. In a descriptive observational study, including 314 students of general schools in Omsk the level of treatment adherence was determined using the QAA-25 questionnaire, using traditional and alternative formulations of individual questions. Results. For adolescents aged 12–14 years a good diagnostic value was shown higher individual testing quality (absence of blank answers to questions) of the tested version of the questionnaire compared to the alternative one. 96.8% of respondents indicated that the wording of the specialized questionnaire was “more accurate” and “more correct”. The tested version of the questionnaire demonstrated good reliability (Cronbach’s alpha total 0.901, based on standardized items αst 0.914) with high internal consistency (consistent elimination of scale items maintains questionnaire validity in the 0.886–0.909 range), with near perfect expert agreement (Cohen’s kappa 0.908). Conclusion. The questionnaire is characterized by good validity and has a high internal stability, and the content and wording of all questions of the questionnaire are adequately perceived by the audience for which the questionnaire is designed. This makes it advisable to use it to assess the potential adherence to treatment of adolescents aged 12–14 years.

Background. Psoriasis is an independent risk factor for cardiovascular diseases (CVD). One of the markers associated with the CVD course is epicardial fatty tissue (EFT) that is thicker in psoriasis patients. EFT assessment can be used as a useful indicator of CVD in psoriasis patients. The data about the effect of genetically engineered biological therapy (GEBT), used for psoriasis management, on the EFT thickness is limited. Examination of GEBT effects on EFT may improve our understanding of CVD prevention in psoriasis patients.Objective. The aim of the study is to study the changes in EFT thickness on GEBT.Methods. A prospective cohort study included 56 children with severe and moderate psoriasis. Patients underwent transthoracic two-dimensional echocardiography (M-mode) with EFT thickness assessment and PASI (Psoriasis Area and Severity Index) scoring before the GEBT initiation. All the parameters were re-evaluated after 16 weeks. All patients were divided into three groups according to the initiated therapy: adalimumab, secukinumab and ustekinumab. When dividing the therapy received into groups, the age of the patients was taken into account: inclusion in the adalimumab group was carried out from 4 years, in the secukinumab and ustekinumab groups — from 6 years. Otherwise, the process of group assignment was random. The study results were processed using descriptive statistics methods: the changes in EFT thickness in individual groups were compared via the Wilcoxon test, and results were considered statistically significant at p 0.05.Results. Before the start of therapy, in 56 patients the mean of EFT thickness was 2.11 mm, the mean PASI — 18.32. The adalimumab group had the following indicators: the mean EFT thickness before the therapy was 2.1 mm, and it has decreased to 1.77 mm after 16 weeks of therapy. The mean change in EFT thickness was 0.33 mm, and the median — 0.17 mm [CI 0.33 ± 0.25]. The ustekinumab group: the mean EFT thickness before the therapy was 2.13 mm, 16 weeks after — 1.69 mm. The mean change in EFT thickness was 0.44 mm, and the median — 0.38 [CI 0.44 ± 0.13]. The secukinumab group: the mean EFT thickness before the therapy was 2.08 mm, 16 weeks after — 1.82 mm. The mean change in EFT thickness was 0.27 mm, and the median — 0.27 [CI 0.27 ± 0.07]. Evaluation of indicators via Wilcoxon test has shown statistically significant decrease in the EFT after therapy in all groups (p 0.05). 73% of patients achieved PASI 50, and 6% — PASI 75 in the adalimumab group. 21% of patients did not achieve PASI 50. The mean PASI score before therapy was 16.73 points, and after 16 ± 4 weeks — 6.4 points, the mean dynamics was 10.33 points, the median dynamics was 7 points [CI 10.33 ± 4]. All patients achieved PASI 50, 75.3% — PASI 75, 8% — PASI 90, and 16.7% — PASI 100 in the ustekinumab group. The mean PASI score before therapy was 22.17 points, and after 16 weeks — 3.67 points, the mean dynamics was 19.28 points, the median dynamics was 17 points [CI 18.5 ± 3.03]. All patients achieved PASI 50, 47% — PASI 75, and 11% — PASI 90 in the secukinumab group. The median PASI before therapy was 14.29 points, and after 16 ± 4 weeks — 3.71 points, the mean PASI score before therapy was 14.29 points, and after 16 weeks — 3.7 points, the mean dynamics was 10.59 points, the median dynamics was 10 points [CI 10.59 ± 2.27]. Evaluation of indicators via Wilcoxon test has shown statistically significant decrease in the PASI after therapy in all groups (p 0.05). There were no adverse events leading to cessation of therapy during the follow-up period.Conclusion. All groups have shown decrease in the in EFT thickness and in the PASI score. The most significant dynamics was observed in the ustekinumab group. Research limitations were the small patients sample and the absence of a control group (participants without psoriasis).

Background. Rapp-Hodgkin syndrome is a rare genetic disease from the ectodermal dysplasia group. It manifests with damage of ectodermal structures — layer of embrional tissue that provides the development of many organs and tissues in the body, such as: skin, sweat glands, hair, teeth, and nails. Disease symptoms may range from mild to severe and include dental abnormalities, fragile, thin or no hair, abnormal nails, hypohidrosis (due to the reduced number of sweat glands), cleft lips and palate. Hidradenitis suppurativa is a chronic inflammatory disease that predominantly affects apocrine glands areas. This nosology is characterized by painful nodes, abscesses, and fistulas, prone to relapses and leading to scarring.Clinical case description. The authors present a clinical case demonstrating the combination of Rapp-Hodgkin syndrome and severe hidradenitis suppurativa in 17-year-old male patient.Conclusion. The heterogeneous clinical findings of hidradenitis suppurativa and history of rare genetic disease result in patients' admissions to various medical specialists. Thus, it leads to delayed verification of the diagnosis and incorrect treatment methods. As a result, patients have persistent cosmetic skin defects, possible complications of irrational treatment, and decreased quality of life by the time of diagnosis.