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The aim of the investigation was to study the factors influencing the radial stiffness of the thoracic aorta stent-grafts with the stent elements made of nitinol tubes by laser cutting and thermal shape setting. Materials and Methods. The work used stent elements made by different technologies by two different manufacturers from a nitinol tube with a wall thickness of 0.5 mm (E1) and 0.4 mm (E2), with a final diameter of 20 mm. Height of cells E1 — 15 mm, E2 — 12.5 mm. The stents were manually attached to a tubular woven non-crimped base (PTGO Sever, Russia) with a 6/0 suture, resulting in either single or continuous stitches. In the RLU124 radial force tester (Blockwise Engineering LLC, USA), each of the four stent-grafts, as well as their individual stent elements, were compressed by 10 mm from the initial diameter. The dependence of the radial forces on deformation under loading and unloading was graphically presented. The temperature and enthalpy of phase transitions of nitinols into the austenite (Af) and martensitic (Mf) phases were studied using differential scanning calorimetry (DSC-3; Mettler Toledo, USA). All indicators were compared with the characteristics of two commercial models — Cronus (China) and E-vita Open Plus (Germany). Results. Four prototypes of SibHybrid stent-grafts were tested; those differed in their stent elements, distances between them, and the type of sutures (single or continuous). The stent elements of the models studied differed in the values of Af, Mf, and the enthalpy of phase transitions of nitinols. The hardest stent was the E2 prototype. The fixation of stent elements to the woven fabric in the graft increased the radial force by 4.0–5.5 times. During compression by 50 and 20% of the original diameter, the SibHybrid models developed radial force 4.5–6.0 times greater compared with the E-vita Оpen Plus model. The radial force values of SibHybrid models were almost the same as for the Cronus and models at 20% compression. Using continuous twining round suturing increased the radial force by about 10 N; accordingly, SibHybrid E2 had the highest radial force because it was fixed by a continuous suture. The density of the stent elements fixed on the fabric did not affect the radial force of the stent-graft as a whole. Conclusion. In the manufacture of stent elements from nitinol tubes, the main factor determining the radial stiffness is the technology of nitinol shape setting. With the standard technology of thermal shape setting, radial force can be changed by varying the height of the structure cell element and the cross-sectional area of the cell bars, as well as the suturing technique.

The article analyzes the transformation of migration processes in the south-east of Ukraine, caused by the consequences of the armed conflict in this territory. The study touches upon the problem of adaptation of internally displaced persons, which requires its solution, but the measures taken by the state do not allow settling the problem of accommodation, employment, observance of the constitutional rights of people who have moved from Donetsk and Lugansk regions to other ones of the country. Forced migration, which arose as a result of the military confrontation and the deterioration of the socio-economic situation, deprived the majority of the working-age population of the opportunity to work in accordance with the acquired qualifications. This led to significant migration changes in the region. A lot of citizens have become either internally displaced persons, or rushed to other countries, residents of the south-eastern regions of Ukraine, more often choose the Russian Federation. Therefore, this article discusses measures to regulate migration processes in the Russian Federation, which was largely influenced by the current situation, especially at the beginning of the exacerbation. An analysis of the subsequent steps taken by the Russian authorities shows that in 2015-2016 individual measures did not solve the problem as a whole. Therefore, later the draft law on simplifying Russian citizenship for compatriots who live in countries with a difficult situation or in conditions of armed conflicts was adopted in 2018. Finally, in 2019, Decrees of the President of the Russian Federation No. 183 and No. 187 with July amendments for citizens of Ukraine from other regions, and then additions to the Federal Law “On Citizenship of the Russian Federation” (April 2020) simplified the situation and determined the interest in these citizens. And the statistical data of the Ministry of Internal Affairs of the Russian Federation cited in the study confirm the growth trend in the number of such citizens. Although the lack of demand for their professional experience, the problems of settling in a new place require further regulation. Some of the citizens who have received Russian citizenship remain to live and work in the unrecognized republics. After analyzing the ongoing changes in the migration situation in the south-east of Ukraine, the features that affect its development and further migration trends in this region were identified. This article points to a possible military exacerbation, which determines the further development of the situation.

В статье рассмотрены понятия: информационная угроза, информационная безопасность, социальная безопасность, государственная и национальная безопасность. Определены ключевые характеристики информационной и социальной безопасности. Показана связь между политической, социально-экономической жизнью общества и их влиянием на механизм обеспечения социальной безопасности молодежи как организационно-управленческой основы безопасности государства.

Статья посвящена изучению особенностей романа Гайто Газданова «Переворот». Впервые предпринята попытка литературоведческого анализа этого незаконченного романа, опубликованного после смерти писателя. Авторы анализируют причины трансформации романной прозы писателя, так как поэтика романа отличается от произведений, созданных им ранее. Предметом исследования являются стилистические особенности этого произведения. Авторы статьи дают обоснование появлению такого нового жанра в прозе Газданова и уделяют особое внимание сопоставлению проблематики романа и политической ситуации во Франции, а также анализируют влияние публицистической деятельности писателя, которая наложила отпечаток на стиль романа. Писатель раскрывает глубинный драматизм эпохи через ощущения главных героев и показывает сложную картину социальных отношений и политических противоборств., The article is devoted to the study of the features of Gaito Gazdanov's novel "The Coup". For the first time, an attempt was made to analyze this unfinished novel published after the death of the writer. The authors made analyze the reasons for the transformation of the novelist's prose, since the poetics of the novel differs from the works he created earlier. The subject of research is the stylistic features of this work. The authors of the article substantiate the emergence of such a new genre in Gazdanov's prose and pay special attention to comparing the problems of the novel and the political situation in France, and also analyze the influence of the writer's journalistic activities, which left an imprint on the style of the novel. The writer reveals the deep drama of the era through the feelings of the main characters and shows a complex picture of social relations and political confrontations.

The global challenges that humanity is facing today pose the task of higher education to prepare a specialist with fundamental training and the ability to learn throughout life. Fundamentalization of education is not possible without the formation of students' conceptual understanding of the material studied. This problem is quite relevant in the study of mathematics due to the specific nature of this science. The researchers' lack of a unified point of view in determining the essence of the conceptual understanding of mathematics does not allow practitioners to develop tools for assessing the level of conceptual understanding among university students. The purpose the article is to identify and formulate the essential characteristics and pedagogical conditions for the formation of a conceptual understanding of mathematics, as well as to explore the possibilities and effectiveness of the integration of computer modeling as an instrument of forming a conceptual understanding in the process of teaching probability theory to students of technical universities. The study showed that a computer workshop, developed based on identified pedagogical conditions and taking into account the didactic capabilities of ICT in the educational process, is an effective means of developing conceptual understanding when studying a course in probability theory. Students whose curriculum included a workshop with elements of computer modeling have a more excellent knowledge of methodologically significant knowledge and the ability to relate previously learned material to new problems.

The research is devoted to dialect meteorological vocabulary of the Volgograd region dialects, presented on the linguistic maps of the electronic atlas. The lexemes included in the word-building nest with the roots -hmur-, -hmar-, -hmor- are studied. The methods of cartography and recartography of language material are used: structural and semantic features of dialectisms, their place in the Russian national language system, structural and semantic variation by comparing the material of several maps of the dialect atlas are analyzed. The analysis of the material is carried out taking into account the linguo-geographical landscape of the Volgograd region, which was reflected in the conclusions of the article: the map material shows the great semantic and word-building activity of the vocabulary in the late resettlement dialects of the region. We have developed a methodology for the comprehensive analysis of dialect material, which allows to realize the diagnostic capabilities of linguistic dialect maps: tracking the ranges of lexemes, word-building nests, word-building models, as well as the semantic volume of dialect lexemes. The methodology can be applied to the study of any other thematic vocabulary of any region.

The article is devoted to the study of the system of characters, which includes both central and secondary characters in the stories and novels of Gaito Gazdanov, heroes - creators, heroes - writers and their antipodes. The main character is seen as the semantic center of the work, regardless of whether he is the main subject of the narrative or not. In the article, the heroes of novels and stories are systematized according to the selected criteria into separate groups. The dualism of human nature in Gaito Gazdanov's prose is realized with the help of a number of figurative antitheses, one of which is the opposition of creator heroes and destroyer heroes.

The aim of this study was to compare the mechanical properties and thermal stability of the venous wall depending on the treatment method used, and, accordingly, on those structural changes in the tissue that this treatment causes. Bovine jugular vein walls (BJVWs) cross-linked with glutaraldehyde (GA), ethylene glycol diglycidyl ether (DE), and Contegra commercial conduit were evaluated using uniaxial stretching [with and without pre-conditioning (PreC)], differential scanning calorimetry, amino acid analysis, and attenuated total reflection infrared spectroscopy. Fresh BJVW was used as a control. It was shown that failure stress in non-PreC GA-treated and DE-treated materials was lower than that in fresh and Contegra counterparts. Contegra samples were the stiffest among the tested materials. Cyclic preloading leads to distortion of the mechanical behavior of this material, which is heterogeneous in composition and structure. The denaturation temperatures (Td ) of all cross-linked BJVWs were higher than the Td of the fresh vein. The microstructures of the tested BJVWs did not exhibit any differences, but the cross-linking density and hydration of the DE-vein were the highest. GA-cross-linking or DE-cross-linking and isopropanol exposure (Contegra) changed the protein secondary structures of the tested materials in different ways. We hypothesized that the protein secondary structure and hydration degree are the main causes of differences in the mechanical properties and thermal stability of BJVW.

The purpose of the work is to study various aspects of using information and communication technologies to prepare students studying in the direction of training “Applied Mathematics and Informatics.” The educational objectives, principles, and advantages of using ICT in higher education are highlighted. Based on the analysis of educational standards in this area, the goals, objectives, principles, functions of ICT in teaching stochastics are determined. The conclusion is made about a consistent, expedient combination of traditional educational technologies and ICT in the educational process. It is noted that a modern classical university's information and educational environment creates conditions for the training of specialists who meet these requirements.

Bioprosthetic heart valves made from bovine pericardium (BP) and porcine pericardium (PP) preserved with glutaraldehyde (GA) are commonly used in valve surgeries but prone to calcification in many patients. In this study, we compared BP and PP preserved with GA, ethylene glycol diglycidyl ether (DE), and 1,2,3,4,6-penta-O-{1-[2-(glycidyloxy)ethoxy]ethyl}- d -glucopyranose (PE). We studied the stabilities of DE and PE in preservation media along with the amino acid (AA) compositions, Fourier-transform infrared spectra, mechanical properties, surface morphologies, thermal stability, calcification, and the cytocompatibility of BP and PP treated with 0.625% GA, 5% DE, 2% PE, and alternating 5% DE and 2% PE for 3 + 11 d and 10 + 10 d, respectively. Both epoxides were stable in the water-buffer solutions (pH 7.4). DE provided high linkage densities in BP and PP owing to reactions with Hyl, Lys, His, Arg, Ser, and Tyr. PE reacted weakly with these AAs but strongly with Met. High cross-linking density obtained using the 10 d + 10 d method provided satisfactory thermal stability of biomaterials. The epoxy preservations improved cytocompatibility and resistance to calcification. PE enhanced the stress/strain properties of the xenogeneic pericardia, perhaps by forming nanostructures that were clearly visualised in BP using scanning electron microscopy. The DE + PE combination, in an alternating cross-linking manner, thus constitutes a promising option for developing bioprosthetic pericardia.

В данной статье осуществляется исследование сущности и существования традиционных исторических корней культуры, имеющих свое выражение в различных формах, например, в праздниках. Являясь результатом осмысления человечеством самого себя в рамках реального бытия, праздник создает портрет общества каждой эпохи. Он отражает всю систему эстетических, нравственных, этических, религиозных критериев общества, накопленных в историческом беге времени. Важно отметить, что в статье совершается попытка изучения не истории традиции праздника, когда мы имеем дело с прошлым, а с тем, как люди относятся к прошлому. Неповторимый культурный облик каждой эпохи находит свое отражение в праздничной сфере, репрезентирующей набор ценностей, норм, культурных образцов государства., This article examines the essence and existence of traditional historical roots of culture, which have their expression in various forms, for example, in holidays. As a result of humanity's understanding of itself in the framework of real life, a holiday creates a portrait of the society of each era. It reflects the whole system of aesthetic, moral, ethical, religious criteria of society accumulated in the historical run of time. It is important to note that the article attempts to study not the history of the holiday tradition when we are dealing with the past, but with the way people relate to the past. The unique cultural image of each era is reflected in the festive sphere, representing a set of values, norms, cultural patterns of the state.

A method of phosphorylation of pentacyclic triterpenoids derivatives containing an α,β-unsaturated carbonyl fragment in the ring A was described by the example of the reaction of methyl (2-methylidene)-3-oxolup-20(29)-en-28-oate with dimethyl trimethylsilyl phosphite. Methyl 2-dimethoxyphosphorylmethyl-3-oxolup-20(29)-en-28-oate was obtained as two epimers in a 2: 1 ratio in a 70% yield.

Objectives The development of calcification-resistant bioprosthetic materials is a very important challenge for paediatric surgery. The subcutaneous implantation in rats is the well-known first-stage model for this kind of research. Using this model, we aimed to compare calcification of the porcine aortic wall and bovine pericardium and jugular vein wall cross-linked with glutaraldehyde (GA) and ethylene glycol diglycidyl ether (DE). We also determined the efficacy of DE-preserved tissue modification with 2-(2-carboxyethylamino)ethylidene-1,1-bisphosphonic acid (CEABA). Methods Three groups of each biomaterial were evaluated: GA-treated, DE-treated and DE + CEABA-treated. The microstructure of non-implanted biomaterials was assessed by light microscopy after Picro Mallory staining; the phosphorus content of the DE and DE + CEABA samples was assessed by atomic emission spectrometry. Samples were implanted subcutaneously into young rats for 10 and 60 days. The explant end-point included quantitative calcification assessment by atomic absorption spectrophotometry and light microscopy examination after von Kossa staining. Results All GA-treated biomaterials had a high calcium-binding capacity (>100 μg/mg dry tissue). DE preservation decreased the vein wall and pericardium calcium content by 4- and 40-fold, respectively, but was ineffective for the aortic wall. The calculated CEABA content was almost equal in the vein wall and pericardium (17.7 and 18.5 μM/g) and slightly less in the aortic wall (15 μM/g) (P = 0.011). CEABA effectively reduced mineralization in the DE aortic wall and DE pericardium to 10.1 (7.8-21.1) and 0.95 (0.57-1.38) μg/mg but had no effect in the DE vein wall. Mineralization in the GA- and DE-treated aortic and vein walls was predominantly associated with elastin. CEABA modification decreased elastin calcification but did not block it completely. Conclusions Each xenogeneic material requires individual anticalcification strategy. DE + CEABA pretreatment demonstrates a high mineralization-blocking efficacy for the bovine pericardium and should be employed to further develop the paediatric pericardial conduit. Aortic wall calcification cannot be blocked completely using this strategy.

A series of new triphenylphosphonium (TPP) derivatives of the triterpenoid betulin (1, 3-lup-20(29)-ene-3β,28-diol) have been synthesized and evaluated for cytotoxic effects against human breast cancer (MCF-7), prostate adenocarcinoma (PC-3), vinblastine-resistant human breast cancer (MCF-7/Vinb), and human skin fibroblast (HSF) cells. The TPP moiety was applied as a carrier group through the acyl linker at the 28- or 3- and 28-positions of betulin to promote cellular and mitochondrial accumulation of the resultant compounds. A structure–activity relationship study has revealed the essential role of the TPP group in the biological properties of the betulin derivatives produced. The present results showed that a conjugate of betulin with TPP (3) enhanced antiproliferative activity toward vinblastine-resistant MCF-7 cells, with an IC50 value as low as 0.045 μM.

This study evaluated the ability of bisphosphonates (BPAs) of different molecular structures to mitigate the calcification of porcine aortic wall (PAW) and bovine jugular vein wall (BJVW). Tissues cross-linked with glutaraldehyde (GA) or diepoxide (DE) were modified with pamidronic acid (PAM), alendronic acid (ALE), neridronic acid (NER) (type 1 BPAs); 2-(20-carboxyethylamino)ethylidene-1,1-bisphosphonic acid (CEABA), 2-(5-carboxypentylamino)ethylidene-1,1-bisphosphonic acid (CPABA) (type 2); and zoledronic acid (ZOL) (type 3). After implanting the tissue samples subcutaneously in 100 rats, calcification was examined using atomic absorption spectrophotometry (60-day explants) and light microscopy after von Kossa staining (10- and 30-day explants). The calcium contents in GA-BJVW and GA- and DE-PAW increased up to 100-120 mg/g after 60 days, while being 3 times lower in DE-BJVW. In modified and nonmodified PAW samples, calcium phosphates appeared by day 10 and were associated with elastic fibers and devitalized cellular elements. In all groups of BJVW samples, mineralization began in elastic fibers near the subendothelial layer. In addition, calcified collagen was found in the GA-BJVW samples. Minimal calcification was found in GA-PAW treated with type 1 BPAs and CEABA. For DE-PAW and GA-BJVW, the calcium level significantly decreased with PAM and CEABA. Meanwhile, ALE and NER were effective for DE-BJVW.

The formation of the prerequisites for the development of the economy revises the technological process in the country. The ineffectiveness of the activities of the digital economy has led to the formation of new instruments. The new tools regulate the economic system. Tools of the digital economy don’t take account the development of territories in Russia. In accordance with this premise, it is planned to conduct a study comparing the tools of the digital economy to the Russian realities of Russia’s development. The thesis serves the purpose of scientific research. The tasks of scientific research involve the following activities: to the consideration of tools for the development of the digital economy; to the allocation of directions of “gravitation” of tools of the digital economy; to the presentation of the characteristics of digital economy tools; to the formation of the life cycle of the development of the digital economy. The theoretical significance of the study is the regulation of the tools of the digital economy in the Russian realities. The practical significance is based on the importance of the instrumentality in the Russian economy.

The professional training of mathematics students is notable for the large volume and complexity of the content of educational material. In this regard, the problem of conceptual understanding is relevant. Since many concepts in mathematics have a high level of abstraction, studying them, it is essential to create an image of an object through various forms of knowledge representation. Computer simulation in the study of probability theory and its applications (stochastics) help students understand the essence of random phenomena and forms the ability to analyze statistical data. Students whose curriculum includes a computer simulations workshop in the study of stochastics, not only solve problems better but also higher evaluate the value of probabilistic ideas and methods and have a lower level of anxiety. Due to the use of simulations in teaching mathematics students on stochastics, we use a computer as a means of automation of calculations, means of learning, and a tool of knowledge, which corresponds to the principle of the integrated use of information computer technology in the educational process.

The article is devoted to the problem of phenomenological narration. The subject of the study are the concepts of "phenomenological novel", "phenomenological prose", "phenomenological narrative". The authors of the work substantiate the presence of phenomenological tendencies in G. Gazdanov's prose. Particular attention is paid to studying the genre of "novel about the artist" in G. Gazdanov's prose on the example of the novel "Evelina and her friends".

OBJECTIVES In this study, we aimed to determine the incidence of reintervention and calcification of xenografts in paediatric patients who underwent placement of the right ventricle-to-pulmonary artery valved conduits. METHODS We retrospectively analysed clinical data of paediatric patients (1 day-18 years) who underwent right ventricular outflow tract reconstruction using xenograft from 2000 to 2016 at a single centre. RESULTS A total of 301 patients underwent the placement of 337 xenografts, including glutaraldehyde-treated bovine jugular vein (n = 171, 50.7%), glutaraldehyde-treated bovine pericardial valved conduit (n = 75, 22.3%), diepoxy-treated porcine aortic conduit (n = 58, 17.2%) and diepoxy-treated bovine pericardial valved conduit (DE-PVC) (n = 33, 9.8%). There were 284 (84.3%) primary implantations and 53 (15.7%) reimplantations. The median follow-up was 4.2 years (range 1.5 months-14.5 years). The multivariate regression analysis did not reveal statistically significant associations of the first reintervention with the type of xenograft (P = 0.78). At reintervention, calcification of the wall and/or cusps was the main cause of conduit dysfunction in 66.4% of cases. On the basis of the multivariate Cox regression analysis, xenograft types were significant predictors of reintervention caused by conduit calcification (P = 0.012). The diepoxy-treated porcine aortic conduit group had the risk of calcification 3 times higher than the glutaraldehyde-treated bovine jugular vein group (P

Reactions of glutathione (GSH) with O,O-diorganyl dithiophosphoric acids (DTPA) were studied to develop bioactive derivatives of GSH. Effective coupling reaction of GSH with DTPA was proposed to produce the ammonium dithiophosphates (GSH–DTPA) between the NH2 group in γ-glutamyl residue of GSH and the SH group in DTPA. A series of the GSH–DTPA salts based on O-alkyl or O-monoterpenyl substituted DTPA were synthesized. Enhanced radical scavenging activity of the GSH–DTPA over GSH was established with the use of DPPH assay and improved fluorescent assay which utilizes Co/H2O2 Fenton-like reaction. Similarly to GSH, the dithiophosphates induced both pro- and antioxidant effects in vitro attributed to different cellular availability of the compounds. Whereas extracellularly applied GSH greatly stimulated proliferation of cancer cells (PC-3, vinblastine-resistant MCF-7 cells), the GSH–DTPA exhibited antiproliferative activity, which was pronounced for the O-menthyl and O-isopinocampheolyl substituted compounds 3d and 3e (IC50 ≥ 1 μM). Our results show that the GSH–DTPA are promising redox modulating and antiproliferative compounds. The approach proposed can be extended to modification and improvement of bioactivity of various natural and synthetic peptides.

Mechanisms and rates of hydrolytic dephosphorylation of 5′-hydrogenphosphonates, 5′-phosphorofluoridates, and 5′-phosphates of natural and 3′-substituted thymidines in human serum were studied. The stability of 5′-phosphonates of 2′-deoxy- and 2′,3′-dideoxyadenosines in calf and human sera was found.