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The author proposed to open a scientifi consortium on the basis of scientifi and educational organizations located in the member countries of the EAEU. The relevance and importance of creating such a consortium, which are associated with the intensifi of the development of partnerships between the EAEU countries, support for scientifi and technological cooperation between the EAEU countries at the highest state level, as well as the signifi scientifi potential of the EAEU countries and the existing infrastructure, are shown. The author presents priority areas in which scientifi consortiums can be created. Priority areas were determined based on the results of a bibliometric analysis of statistical data on the publication activity of the EAEU countries for 5 years. The analytical service Web of Science Incites was used as an analysis tool. Based on the results of the study, scientifi fronts were identifi - areas with the highest publication activity and citation for each of the EAEU countries. By comparing the directions, the most priority directions for the creation of scientifi consortiums were determined.

Spectroscopic observations of nine cataclysmic variables that have been postulated to contain magnetic white dwarfs were obtained to further characterize their classifications, orbital parameters, inclinations, and/or accretion properties. Zwicky Transient Facility (ZTF) and Transiting Exoplanet Survey Satellite (TESS) data were also used when available. This information enables these systems to be useful in global population and evolution studies of close binaries. Radial velocity curves were constructed for eight of these systems, at various states of accretion. High-state spectra of ZTF0548+53 reveal strong He ii emission, large radial velocity amplitudes, as well as cyclotron harmonics yielding a magnetic field strength of 50 MG, confirming this as a polar system. Analysis of TESS data reveals an orbital period of 92.1 minutes. High-state spectra of SDSS0837+38 determine a period of 3.18 hr, removing the ambiguity of periods found during the low state, and showing this is a regular polar and not a pre-polar system. The ZTF light curve of CSS0026+24 shows a total eclipse with a period of 122.9 minutes, and features indicative of two accretion poles. A new, remarkably large spin-to-orbit ratio is found for ZTF1631+69 (0.61), making it, along with 2011+60 (=Romanov V48), likely stream-accreting intermediate polars. ZTF data reveal the presence of ∼2 mag low states in ZTF1631+69, and along with McDonald Observatory 2.1 m and TESS light curves, confirm a grazing eclipse that is deepest at a narrow subset of beat phases. The TESS data on PTF12313+16 also indicate a partial eclipse. Analysis of ZTF data on SDSS1626+33 reveals a period of 3.17 hr and suggests the presence of a partial eclipse.

The basic principles of the formation and operation of farms in modern conditions of economic development are presented. The main reason for the ineffective functioning of farms is revealed - the lack of capital and the necessary production resources. The authors have shown the need to locate farms in a compact massif. The optimal scheme of the land mass infrastructure has been built. Also, during the study, it was revealed that one of the main conditions that determine the viability of farms is the substantiation and achievement of optimal production and economic parameters. The factors and conditions that must be taken into account when determining the optimal production structure of a farm are indicated. The most important areas of effective activity of farms are considered, one of which is cooperation both with each other and with other agricultural and industrial enterprises engaged in the procurement, processing and sale of agricultural products.

The article highlights the problem of the emigration of young scientists and students from Russia abroad. The factors affecting the retention of foreign students in the country after graduation are presented, as well as the return of Russian students after receiving higher education abroad. The experience of foreign states in stimulating educational immigration has been analyzed, in particular, scientific programs have been considered to attract foreign students for the purpose of studying in higher education institutions. Similarly, scientific, industrial and economic benefits are singled out in the article with the accumulation of intellectual capital in the country. The options for managing intellectual capital are considered, for example, the idea of creating scientific centers on the basis of coworking as an effective method for attracting and engaging young scientists for achieving high scientific results is proposed.

The Earth close approach of near-Earth asteroid 2005 LW3 on 2022 November 23 represented a good opportunity for a second observing campaign to test the timing accuracy of astrometric observation. With 82 participating stations, the International Asteroid Warning Network collected 1046 observations of 2005 LW3 around the time of the close approach. Compared to the previous timing campaign targeting 2019 XS, some individual observers were able to significantly improve the accuracy of their reported observation times. In particular, U.S. surveys achieved good timing performance. However, no broad, systematic improvement was achieved compared to the previous campaign, with an overall negative bias persisting among the different observers. The calibration of observing times and the mitigation of timing errors should be important future considerations for observers and orbit computers, respectively.

This article presents the methodology recommended by the authors for calculating the amount of grants provided from the federal budget in the form of a subsidy for state support for the creation and development of world-class research centers, including international mathematical centers and world-class research centers that carry out research and development on the priorities of scientific and technological development. The methodology involves the distribution of the grant to world-class research centers, depending on the volume of work performed. This is relevant in that at the moment, grants are distributed evenly between world-class research centers every year, and therefore there is no incentive for the centers to intensify work in order to achieve higher values of performance targets. The article thoroughly disclosed the logic of the proposed methodology, presented calculation formulas with explanations. The article discusses the implementation of the tasks of the national project “Science” in terms of creating world-class research centers. The number of centers created in 2019, their types and directions of scientific activity, as well as the number of world-class scientific centers that will be created in subsequent years are indicated in this article. Target performance indicators of the created centers and planned achievements by 2024 are presented. In conclusion, the data presented in the article are summarized, and the positive prospects for Russian science resulting from the creation and functioning of world-class research centers are examined. The conclusion also indicates how the technique developed by the authors can stimulate world-class research centers to fruitful scientific activity.

In a recent paper by A. A. Klyachko, V. Y. Miroshnichenko, and A. Y. Olshanskii, it is proven that the center of any finite strongly verbally closed group is a direct factor. In this paper, we extend this result to the case of finite normal subgroups of any strongly verbally closed group. It follows that finitely generated nilpotent groups with nonabelian torsion subgroups are not strongly verbally closed. [ABSTRACT FROM AUTHOR]

The assertion in the title implies that many interesting groups (for example, all non-abelian braid groups or |$\textbf{SL}_{100}(\mathbb{Z})$|⁠) are not strongly verbally closed, i. e. they embed into some finitely generated groups as verbally closed subgroups, which are not retracts. [ABSTRACT FROM AUTHOR]

Additive technologies open up new possibilities for creating materials with controlled structural features including ceramic composites. Such composites have good strength properties, fracture toughness and toughness. But not all properties are studied well. In order to predict the mechanical behavior of transformation-hardened ceramic composites with a controlled structure under dynamic loads, it is convenient to use methods of numerical analysis.The aim of this work was to investigate the influence of loading speed on microstructure evolution of ZTA nanocomposites obtained by additive tecnology of fused deposition modeling. Within the framework of the study physical and mathematical model that is used in computational mechanics of materials is developed. In the paper is shown the influence of the loading rate on the strain rate in the region of the shock transition for materials based on Al _2 O _3 - 20%ZrO _2 system. The research shows nonlinear effects under intense dynamic loads in the shown composite materials are bound up with either the processes of self-organisation of deformation modes at the mesoscopic level or the occurrence of martensitic phase transformations in matrix volumes adjacent to the strengthening particles.

The single-layer epithelium of the gastrointestinal tract is a dynamically renewing tissue that ensures nutrient absorption, secretory and barrier functions and is involved in immune responses. The basis for this homeostatic renewal is the Wnt signaling pathway. Blocking this pathway can lead to epithelial damage, while its abnormal activation can result in the development of intestinal tumors. In this study, we investigated the dynamics of intestinal epithelial cells and tumorigenesis using a conditional mouse model. Using single-cell and bulk RNA sequencing and histological analysis, we elucidated the cellular responses following the loss of specific cell types. We focused on the fate of cells in the lower parts of the intestinal crypts and the development of colon adenomas. By partially inactivating the transcription factor Tcf4, a key effector of the Wnt signaling pathway, we analyzed the regeneration of isolated hyperproliferative foci (crypts). Our results suggest that the damaged epithelium is not restored by a specific regeneration program associated with oncofetal gene production, but rather by a standard homeostatic renewal pathway. Moreover, disruption of Tcf4 in secretory progenitors resulted in a significant shift in the cell lineage from Paneth cells to goblet cells, characterized by morphological changes and loss of Paneth cell-specific genes. We also found that hyperactivation of the Wnt signaling pathway in colonic adenomas correlated with the upregulation of genes typical of Paneth cells in the intestine, followed by the emergence of secretory tumor cells producing the Wnt3 ligand. The absence of Tcf4 led to a phenotypic shift of the tumor cells towards goblet cells. Our study presents a new model of epithelial regeneration based on the genetically driven partial elimination of intestinal crypts. We highlight the critical role of Tcf4 in the control of cell lineage decisions in the intestinal epithelium and colon tumors.

Since its discovery, Aire has been the topic of numerous studies in its role as a transcriptional regulator in the thymus where it promotes the "promiscuous" expression of a large repertoire of tissue-restricted antigens (TRAs) that are normally expressed only in the immune periphery. This process occurs in specialized medullary thymic epithelial cells (mTECs) and mediates the elimination of self-reactive T cells or promotes their conversion to the Foxp3 + regulatory T cell lineage, both of which are required for the prevention of autoimmunity. In recent years, there has been increasing interest in the role of extrathymic Aire expression in peripheral organs. The focus has primarily been on the identification of the cellular source(s) and mechanism(s) by which extrathymic AIRE affects tolerance-related or other physiological processes. A cadre of OMICs tools including single cell RNA sequencing and novel transgenic models to trace Aire expression to perform lineage tracing experiments have shed light on a phenomenon that is more complex than previously thought. In this chapter, we provide a deeper analysis of how extrathymic Aire research has developed and progressed, how cellular sources were identified, and how the function of AIRE was determined. Current data suggests that extrathymic AIRE fulfills a function that differs from what has been observed in the thymus and strongly argues that its main purpose is to regulate transcriptional programs in a cell content-dependent manner. Surprisingly, there is data that also suggests a non-transcriptional role of extrathymic AIRE in the cytoplasm. We have arrived at a potential turning point that will take the field from the classical understanding of AIRE as a transcription factor in control of TRA expression to its role in immunological and non-immunological processes in the periphery., (© 2024. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.)

Intestinal epithelial cells have the capacity to upregulate MHCII molecules in response to certain epithelial-adhesive microbes, such as segmented filamentous bacteria (SFB). However, the mechanism regulating MHCII expression as well as the impact of epithelial MHCII-mediated antigen presentation on T cell responses targeting those microbes remains elusive. Here, we identify the cellular network that regulates MHCII expression on the intestinal epithelium in response to SFB. Since MHCII on the intestinal epithelium is dispensable for SFB-induced Th17 response, we explored other CD4+ T cell-based responses induced by SFB. We found that SFB drive the conversion of cognate CD4+ T cells to granzyme+ CD8α+ intraepithelial lymphocytes. These cells accumulate in small intestinal intraepithelial space in response to SFB. Yet, their accumulation is abrogated by the ablation of MHCII on the intestinal epithelium. Finally, we show that this mechanism is indispensable for the SFB-driven increase in the turnover of epithelial cells in the ileum. This study identifies a previously uncharacterized immune response to SFB, which is dependent on the epithelial MHCII function., (© 2023 Brabec et al.)

Actin is a multi-functional protein that is involved in numerous cellular processes including cytoskeleton regulation, cell migration, and cellular integrity. In these processes, actin's role in respect to its structure, complex mechanical, and protein-binding properties has been studied primarily in the cytoplasmic and cellular membrane compartments. However, its role in somatic cell nuclei has recently become evident where it participates in transcription, chromatin remodeling, and DNA damage repair. What remains enigmatic is the involvement of nuclear actin in physiological processes that lead to the generation of germ cells, in general, and primary spermatocytes, in particular. Here, we will discuss the possible role and nuclear localization of actin during meiotic prophase I and its interaction with chromatin remodeling complexes, the latter being essential for the control of pairing of homologous chromosomes, cross-over formation, and recombination. It is our hope that this perspective article will extend the scope of actin's nuclear function in germ cells undergoing meiotic division., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Petrusová, Manning and Filipp.)

Interleukin (IL)-17 protects epithelial barriers by inducing the secretion of antimicrobial peptides. However, the effect of IL-17 on Paneth cells (PCs), the major producers of antimicrobial peptides in the small intestine, is unclear. Here, we show that the targeted ablation of the IL-17 receptor (IL-17R) in PCs disrupts their antimicrobial functions and decreases the frequency of ileal PCs. These changes become more pronounced after colonization with IL-17 inducing segmented filamentous bacteria. Mice with PCs that lack IL-17R show an increased inflammatory transcriptional profile in the ileum along with the severity of experimentally induced ileitis. These changes are associated with a decrease in the diversity of gut microbiota that induces a severe ileum pathology upon transfer to genetically susceptible mice, which can be prevented by the systemic administration of IL-17a/f in microbiota recipients. In an exploratory analysis of a small cohort of pediatric patients with Crohn's disease, we have found that a portion of these patients exhibits a low number of lysozyme-expressing ileal PCs and a high ileitis severity score, resembling the phenotype of mice with IL-17R-deficient PCs. Our study identifies IL-17R-dependent signaling in PCs as an important mechanism that maintains ileal homeostasis through the prevention of dysbiosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

The intestinal microbiota is known to influence postnatal growth. We previously found that a strain of Lactiplantibacillus plantarum (strain Lp WJL ) buffers the adverse effects of chronic undernutrition on the growth of juvenile germ-free mice. Here, we report that Lp WJL sustains the postnatal growth of malnourished conventional animals and supports both insulin-like growth factor-1 (IGF-1) and insulin production and activity. We have identified cell walls isolated from Lp WJL , as well as muramyl dipeptide and mifamurtide, as sufficient cues to stimulate animal growth despite undernutrition. Further, we found that NOD2 is necessary in intestinal epithelial cells for Lp WJL -mediated IGF-1 production and for postnatal growth promotion in malnourished conventional animals. These findings indicate that, coupled with renutrition, bacteria cell walls or purified NOD2 ligands have the potential to alleviate stunting.

Male infertility affects approximately 14% of all European men, of which ~44% are characterized as idiopathic. There is an urgency to identify the factors that affect male fertility. One such factor, Autoimmune Regulator (AIRE), a protein found in the thymus, has been studied in the context of central tolerance functioning as a nuclear transcription modulator, responsible for the expression of tissue-restricted antigens in specialized thymic cells that prevent autoimmunity. While its expression in the testes remains enigmatic, we recently observed that sterility in mice correlates with the absence of Aire in the testes, regardless of the deficient expression in medullary thymic epithelial cells or cells of the hematopoietic system. By assessing the Aire transcript levels, we discovered that Sertoli cells are the exclusive source of Aire in the testes, where it most likely plays a non-immune role, suggesting an unknown mechanism by which testicular Aire regulates fertility. Here, we discuss these results in the context of previous reports which have suggested that infertility observed in Aire deficient mice is of an autoimmune aetiology. We present an alternative point of view for the role of Aire in testes in respect to fertility altering the perspective of how Aire's function in the testes is currently perceived.