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Products made of metals and alloys with a fine-grained structure, which have high physical, mechanical and operational characteristics, are becoming increasingly in demand in many technical and technological fields. The most common and efficient technologies for the production of parts from this class of materials are various processes of severe plastic deformation (SPD) (in general practice, at low homologous temperatures). At the same time, to achieve high degrees of deformation, a significant part of metals and alloys require increased processing temperatures, undergo significant heating during deformation processes, which may be accompanied by changes in the grain and subgrain structure due to recovery and recrystallization processes. An empirical approach to the development of SPD modes that ensure the formation of the necessary grain structure requires huge time and financial costs, and therefore considerable attention is paid by researchers in the field of solid mechanics and metal forming to approaches and methods of mathematical modeling. In connection with the foregoing, the number of publications on this subject has been intensively growing in recent years. The currently known models differ significantly in their approaches, the depth of penetration into the physics of processes, and the scope of consideration. The proposed brief review is focused on a qualitative analysis of works on this topic, a preliminary classification of existing models according to their purpose, versatility, and functionality. It seems possible to single out the two most common approaches to describing the change in the grain structure in the processes of thermomechanical processing of metals and alloys: continual (in most cases, single-level) and multilevel, based on the introduction of internal variables and physical theories. This review is devoted to the consideration of publications focused on the first of these approaches. Until now, the most common are macrophenomenological continuum models based on the analysis of experimental data conducted both in laboratories on macrosamples and in real production conditions. Models of this class are usually formulated in the form of operator relations over field quantities, they are relatively easy to implement due to their easy “embedding” into widely used commercial software packages, but they require significant costs for experiments to identify models, they are characterized by a low degree of versatility. Continuous theories are relatively less common, but still often used. These theories are based on the description of physical mechanisms and the evolution of the structure of metals and alloys in terms of continuum variables.

It is well known that the performance properties of products made of metals and alloys are determined mainly by the meso- and microstructure of the latter. The structure of materials is formed and undergoes significant changes in the processes of manufacturing parts and structures using thermomechanical processing methods. A very important parameter that determines the physical and mechanical characteristics of materials is the grain structure (size, shape, relative positions of grains and inclusions of various phases). In recent decades, in this regard, special attention has been paid to the processes of severe plastic deformation (SPD), which make it possible to obtain a submicro- and nanocrystalline grain structure, which provides a significant increase in the performance properties of products made of metals and alloys. The development of SPD technologies in modern conditions is unthinkable without mathematical modeling of the processes under consideration; the most important component in the development of such a "toolkit" are constitutive relations (or, more broadly, constitutive models). In connection with the foregoing, the latter should be able to describe the evolutionary structure at various scale levels. Until now, the practice of developers of materials processing technologies has been dominated by the use of macrophenomenological models based on classical continuum theories of plasticity, viscoplasticity, and creep. From the second half of the 20th century to the present, various improvements to the constitutive models of the above class have been proposed, in which additional parameters and kinetic equations are introduced for them, describing certain characteristics of the structure of materials. As a rule, such models make it possible to obtain an adequate picture of the changing structure, however, for specific materials and methods of thermomechanical treatment. At the same time, such models, unfortunately, do not have the necessary universality; when changing the material or processing method, they have to be significantly “customized” to specific conditions, up to a complete change in the relationships included in the model. A brief review of works devoted to the creation and application of models of this class is given in the previous article by the authors. The most promising and possessing a significant degree of universality, according to the authors, are currently multilevel constitutive models based on the introduction of internal variables and physical theories of plasticity (elastoviscoplasticity). A review of works that consider various aspects of the formulation, modification, numerical implementation and application of such models is proposed in this article. The main attention is paid to models focused on the description of changes in the structure of materials due to dislocation-disclination mechanisms; a brief note is given on models that take into account thermally activated diffusion mechanisms, due to which the processes of recovery and recrystallization are realized.

Nowadays, blockchain attracts the attention of more and more scientists. This is due to the high interest of the world community in this topic, the high pace of development of blockchain technology and its introduction into the life of society in the 21st century. It is worthwhile noting that blockchain technology is important for the future of humanity, because it allows people to build trust. Trust will be built in every area in the finances, real estate, healthcare, business and other life areas of society. Owing to the great prospects for the development of this technology, the attention of linguists is attracted by the fact of the appearance of lexical formatives connected with blockchain. First of all, loanwords are the transition of elements of one language to another as a result of the interaction of languages, or the elements themselves transferred from one language to another. Due to the fact that works about the blockchain initially appeared in English, the lexical units of this topic came to Chinese from English. We provide a classification and also determine the most common ways of loanwords from English to Chinese in blockchain. The relevance of study is determined by the lack of knowledge of English loanwords in Chinese in the field of blockchain. When training specialists in translation, the topic of blockchain remains understudied, due to the difficulties in translation terminology. Thus, studying loanwords can improve the skills of translators, help them avoid mistakes when translating from English to Chinese and vice versa.

The current state of materials constitutive models and the computer technology development make it possible to numerically implement complex multilevel models that allow describing the material structure evolution. In this regard, it is possible to formulate optimal control problem for metal forming processes in order to create the required performance characteristics of finished products and their ingots. To solve this problem in this study, the effective multilevel modeling approach is used to describe the thermomechanical treatment of polycrystalline materials. The model is based on this approach with the introduction of internal variables, in which the carriers and physical mechanisms of the processes of hot intense plastic deformation are explicitly considered. At deformation temperatures order of 0.5 homologous and above, recrystallization process have a special effect on the formation and change of the grain and defect material structure. The paper considers the problem of determining the critical deformation of dynamic recrystallization initiation, that depending on the material texture and the mutual misorientation of neighboring grains. Numerical experiments of the multilevel model are used to simulate two stages of inelastic deformation for this purpose. At the first stage, cold inelastic deformation by simple shear and compression is considered, that leading to the formation of a corresponding texture. At the second stage, uniaxial hot tension deformation is considered. The initial distribution of crystallographic grain orientation is assumed to be uniform. Two variants of the grains mutual misorientation with the prescribed increased and decreased values of the average misorientation angles are considered. The recrystallization process is not explicitly modeled. The current model is intended to assess the recrystallization critical deformation. It is shown that the mutual misorientation of grains, rather than texture, has the most influence on the critical deformation. An increase in the angle of grains mutual misorientation contributes to an earlier start of the dynamic recrystallization process. The formation of a deformation texture leads to a decrease in the angle of mutual misorientation, and, accordingly, to a decrease in dynamic recrystallization intensity. Despite this, with an increase of deformation, the driving force of recrystallization (the average value of the difference of stored energy between neighbor grains) is increases, which leads to the implementation of dynamic recrystallization.

Differential expression of 30 584 genes from a microarray was studied in the liver of male Wistar rats, fed for 63 days with high-fat high-fructose diet supplemented with L-carnitine, resveratrol, tyrosine, or tryptophan, using the method of whole-transcriptome gene expression profiling according to the Agilent One-Color Microarray-Based Gene Expression Analysis Low Input Quick Amp Labeling protocol (version 6.8). To identify metabolic pathways (KEGGS) that are the targets of the applied dietary treatments, transcriptomic data were processed with bioinformatics methods in the R environment. The data obtained suggest that the intake of biologically active substances, i.e., lipid metabolism modulators (including L-Car, Res, and Tyr and Trp aromatic amino acids), despite clear differences in primary targets of their effects and phenotypic consequences for the organism at tissue and organ levels, at the intermediate stages engages a complex of genes that are largely similar and interrelated in their function. These genes are involved in the regulation of cell cycle, proliferation, apoptosis, intercellular interactions, immune response, and inflammation. Moreover, the sign of DE of each of these genes, taken separately, does not allow for unambiguous prediction the direction of processes manifested in strengthening or, alternatively, attenuation of lipogenesis and the observed accumulation of fatty inclusions in the liver cells. Newly described, not reported in the available literature, is the differentiated effect between L-Car, Res, and Tyr, on one hand, and Trp, on the other hand, on the metabolic pathway of arachidonic acid, including the formation of oxylipins (lipoxins), prostaglandins, and thromboxanes.

We present a modification of the Ramsey model that describes the consumer behavior of the households. We assume that the salary of the households is a stochastic process, defined by the stochastic differential equation (SDE). The impact of the large amount of the households can be modelled by a mean field term. This leads to a Kolmogorov–Fokker–Planck equation, evolving forward in time that describes the evolution of the probability density function of the households. Considering a Hamilton–Jacobi–Bellman equation, evolving backwards in time that describes the optimal strategy of the households behavior, we obtain a Mean Field Game problem. We present a self-similar solution of the Hamilton–Jacobi–Bellman equation and introduce the numerical solution of the Kolmogorov–Fokker–Planck equation.

An optimal control problem modeling the economic behavior of a representative household is studied. The existence of its solution is proved, necessary optimality conditions in the form of the Pontryagin–Clarke maximum principle are obtained, and an optimal control synthesis is constructed. The model is identified against Russian statistical data. The model is used to analyze consumer crediting in Russia and its influence on the household economy under COVID-19 pandemic conditions.

We evaluated the temperature of 10% conversion (T10) of the CO oxidation reaction on the Co3O4/SiO2 catalyst as a tool for the rapid optimization of the catalyst synthesis through a simultaneously probabilistic and deterministic approach (SPADA) to the design of experiment (DOE). Multiparameter analysis (5 parameters on 4 levels) with simultaneous modification of several parameters was carried out to improve the solution combustion synthesis of the Co-based catalyst. We studied a four-component chemical system consisting of С2H5NO2 (glycine), Co (NO3)2⋅6H2O (cobalt nitrate), NH4NO3 (ammonium nitrate), and SiO2. A mathematical optimization model was built based on 16 experiments. The methodological aspects of the SPADA to the DOE were described and experimentally validated. The response of the T10 parameter was evaluated as a function of the active mixture composition, calcination parameters, and ratio between active phase and supporting material. Strong and weak parameters were identified, and the optimal synthesis conditions were predicted and experimentally verified.

We present an approach to describe the stock market crises based on Mean Field Games (MFGs) and Optimal Control theory with a turnpike effect. The impact of the large amount of high-frequency traders (HFTs) can be modeled via a mean field term. We introduce the turnpike as a function that relies on the changes of the asset share price. An MFG is a coupled system of PDEs: a Kolmogorov–Fokker–Planck equation, evolving forward in time, and a Hamilton–Jacobi–Bellman equation, evolving backwards in time. The ill-posedness of this system comes from a turnpike effect. The numerical solution of an extremal problem that is dual to a PDE system is presented. We apply this approach to describe the Chinese stock market crash in 2015 considering the representative stock of CITIC Securities (ticker 600030). We consider HFTs that form a dominating bull and bear market. As a result, the bull strategy imitators do not make any profit.

BACKGROUND The self-isolation regime introduced to limit the spread of COVID-19 disrupted the habitual way of life of the majority of the population, which could cause increased anxiety and depressive states in some citizens and lead to the development of acute exotoxicosis. AIM OF STUDY To identify the impact of the COVID-19 pandemic on the structure of acute poisonings based on their comparative analysis for March-May in 2019 and 2020. MATERIAl AND METHODS “Hospital patient cards” of patients who were treated in the Department of Acute Toxicosis and Somatopsychiatric Disorders of the N. V. Sklifosovsky Research Institute for Emergency Medicine in March–May, 2019 and 2020. The Statistica 10.0 program was used for data processing. RESUlTS The total number and gender composition of patients with acute poisonings (AP) did not differ significantly in the compared periods. In 2020, the share of people aged 30–39 increased by 23%, while patients over 50 decreased by 7%. In 2020, the frequency of AP caused by medicines decreased by 10%, with sedatives and antidepressants prevailing. There has been an increase in cases of overdose with NSAIDs, antibiotics and antiviral drugs, probably as a result of self-treatment for Covid-19. The share of drug and psychoactive substance poisoning increased by 5%, mainly due to overdoses of synthetic drugs and combinations of drugs of different groups. At the same time, the number of cases of recreational drug use decreased 2.4-fold. In March-May 2020, the number of patients with severe AP caused by alcohol increased 4-fold, and the number of people with other forms of AP hospitalized with alcohol intoxication grew 2.7-fold. Additionally, twice as many household AP have been caused by chlorine vapor, as well as poisoning with isopropyl alcohol, which can be associated with frequent improper use of disinfectants. CONClUSION Thus, the pandemic and the introduction of restrictive measures for COVID-19 affected the structure of acute exotoxicosis in Moscow in the period March-May 2020. The revealed changes in the structure of acute poisoning to a certain extent reflect global trends.

A multilevel mathematical model is proposed for studying the technological processing of metals and alloys by severe plastic deformation. The model is based on crystal elasto-viscoplasticity and can describe the evolving structure as well as predict crystallographic texture formation. A geometrically nonlinear nonstationary boundary value problem of quasi-static elasto-viscoplastic deformation of macroscopic polycrystalline samples is formulated in rate form, including systems of equations describing physical mechanisms at various structural scale levels. A distinctive feature of the proposed formulation is that it takes into account variable contact conditions on the material surface specified for each moment of the loading process. As a basic constitutive model, a two-level model of a polycrystal is used in which the characteristics of a macroscopic representative volume are calculated by consistent statistical averaging over the values of similar quantities for the contained mesoscopic elements (crystallites). Within the approach used, information on crystallographic textures in different parts of the workpiece is provided in the form of samples of crystal lattice orientations. The associated output data of numerical calculations are reproduced in a reduced form using cluster analysis methods. The developed apparatus is applied to study the drawing of a solid copper cylinder.

Submicron powder of non-stoichiometric hafnium carbonitrides (HC0.5N0.2) was fabricated by the mechanochemical synthesis method. It was shown that during the first milling stages, primarily reaction between hafnium and carbon took place. The nitridation occurred later when fresh metal surfaces started to form through defragmentation of the brittle layer of a carbon-solid solution. The synthesized powder was consolidated by spark plasma sintering approach to producing dense bulk hafnium carbonitride ceramics. Hardness and fracture toughness measured on consolidated samples were 20.8 ± 1 GPa и 3.5 ± 0.2 MPa∙m1/2, respectively. The obtained results were compared with previously reported data.

Specialized products and dietary supplements, enriched with complexes of minor biologically active substances (BAS), are often offered as components of therapeutic diets in the treatment of obesity and metabolic syndrome. At the same time, the possible effects of the interactions of BAS when consuming a multicomponent product have not been studied enough. The aim - to study the action on rats' organism of a complex supplement (RС), containing resveratrol (Res) and L-carnitine (L-Car), when consumed with a standard balanced or hypercaloric diet. Material and methods. Male Wistar rats received for 63 days a standard balanced diet (SD) or a high-fat-high-carbohydrate diet (HFCD) with an excess of total fat (30%) and fructose (20% solution instead of drinking water), or the same diets supplemented with RС in a low (25 mg/kg body weight as Res and 300 mg/kg body weight as L-Car) or high (50 and 600 mg/kg body weight, respectively) doses. The muscle grip strength, behavioral reactions in tests of the conditioned passive avoidance reflex (CPAR) and elevated plus maze (EPM) were studied. At the end of the experiment, the mass of adipose tissue and internal organs was determined together with the activity of microsomal and cytosolic liver enzymes for specific substrates, plasma biochemical parameters, liver morphology by lightoptical microscopy, accumulation of lipofuscin-like granules (LLG) in the liver and kidneys by laser confocal microscopy. Results. In the rats fed HFCD, compared with SD, there was an increase in the mass index of liver, total inguinal and retroperitoneal white adipose tissue, in the levels of glucose and triglycerides, in the activity of hepatic CYP1A1 and CYP3A monooxygenases, UDPglucuronosyltransferase, heme oxygenase, and simultaneous decrease of high and low density lipoprotein cholesterol, and quinone oxidoreductase activity. The RС intake stimulated the locomotor activity of rats in EPM, however, this effect was less pronounced against the background of HFCD consumption. In rats consuming SD (but not HFCD), the addition of RС caused an increase in search activity and anxiety according to the EPM and CPAR data. The effect on short- and long-term memory retention was statistically insignificant. RС intake did not have hypolipidemic and hypoglycemic properties but caused in low dose an increase in the ratio of the activity of transaminases AST/ALT in animals fed HFCD. The liver CYP3A activity increased in rats supplemented with RС in high dose fed HFCD. In the kidneys of animals, the consumption of RС resulted in increased accumulation of LLG. Conclusion. When studying the effect of the complex supplement RС on normal and obese rats according to the studied physiological, morphological and biochemical indexes, no positive effects were revealed, that would not have manifested themselves for Res and L-Car separate intake. No evidence of synergistic action of L-Car and Res were found, and some of the effects of the complex supplement can be considered as adverse. This requires careful assessment when combined using these substances in complex diet therapy of metabolic disorders in humans.

The processes of current flow and reaction initiation in a mixture of Ti–Cu spherical particles were studied in model experiments and in real conditions of SPS processing. Our results allow us to conclude that the local overheating during SPS-consolidation of powder materials is caused by the formation of some preferable current pathways within which current density is markedly greater than within the adjacent areas. This leads to the breakdown of thin dielectric layers (oxide films, vacuum nanogaps) at particle-to-particle contacts, the conductivity of this route sharply grows, and the constituent particles become overheated selectively. In turn, local overheating gives start to SHS reaction and formation of reacted areas in the sample bulk. Our results may turn useful to those engaged in the optimization of process charts and process conditions for SPS-consolidation of materials.

Nowadays, computer games occupy a large share of the entertainment industry market: according to data for 2019, the market volume was $ 152.1 billion (for comparison, the market volume in 2018 was $ 137.9 billion). The growing popularity of the industry led to the inclusion of computer games in 2005 on the UNESCO World Heritage List, and in 2003 – to the establishment of a video game award by the British Academy of Film and Television Arts. Computer games are increasingly penetrating our lives, and thus follows the language of “gamers”, exerting an increas-ing influence on the normative language. Computer games are a vast topic for research and study, especially in terms of language and teaching. Teaching translation in the modern world should in-clude a comprehensive preparation of future specialists for work. In the current education system of the Russian Federation, there is no professional training of translators for the localization of computer games, therefore, translators who wish to work in this area need to undergo additional training outside the higher education system. This brings to the fore the issue of needing to identify the features of the translation process and localization of computer games in order to improve the quality of teaching translation. We consider the features of translation and localization from English into Russian based on the texts of the computer game “The Witcher 3: Wild Hunt”.

World War One had an impact not only the development of international relations throughout the 20th century, but also led to the creation of air forces of different countries. More than 30 countries participated in the First World War. The British Empire, which fought on the side of the Entente, was one of them. During the First World War, the importance of the Air Force increased. It played a decisive role in gaining dominance amidst the aerospace. Aviation, which tasks included aerial reconnaissance and bomb attacks, evolved significantly. A huge number of new experimental military equipment have appeared. All of this produced a huge number of military slang terms. In this study, we will examine the slang terms that appeared in the slang of the British Air Force during the First World War, classify them and make a conclusion about the influence of the First World War on the development of military slang terms. During the training of specialists in the linguistic support of military activity, the topic of military slang remains understudied, which is why interpreters have difficulties in translating slang units. Therefore, the studying of this phenomenon can improve the skills of military interpreters and allow them to avoid major mistakes in their professional activity.

Convolution is the most time-consuming operation in modern deep artificial neural networks, so its performance is crucial for fast inference. One of the standard approaches to fast convolution computation is to use GeMM-based convolution algorithms relying on efficient general matrix multiplication (GeMM) from optimized BLAS libraries. However, commonly used GeMM-based algorithms may cause significant memory overhead or avoid it only at the cost of worse performance. In this paper, we propose a novel convolution algorithm, p-im2col, based on a well-known im2col algorithm that avoids memory overhead by splitting a single multiplication of a large matrix into several multiplications of smaller matrices. We theoretically and experimentally compare our algorithm with two other GeMM-based algorithms: im2col, which is widely used as a baseline, and the memory-efficient kn2row-aa. We measure the inference time of these algorithms on central processing units of x86, x86_64, ARM, and MIPS architectures for a large set of convolutional parameters. The proposed algorithm demonstrates a speedup over im2col and kn2row-aa in a number of cases and a significant reduction in additional memory requirements compared to im2col. Based on our experiments, we present a new convolution algorithm selection scheme that considers memory restrictions, CPU architecture, and convolutional parameters and provides a noticeable advantage over each particular algorithm.

The use of nutraceuticals with anti-inflammatory and hypolipidemic activity in the composition of foods for special dietary uses and dietary supplements is one of the effective methods of dietary therapy of alimentary obesity and related diseases. The aim was to study the effect of the combined intake of resveratrol and L-carnitine (RC) on the expression of genes responsible for the metabolism of carbohydrates, fats and inflammatory reactions in the liver and kidneys of rats in normal conditions and with diet-induced obesity. Material and methods. Male Wistar rats received for 63 days a standard balanced diet or a high-fat-high-carbohydrate diet (HFCD) with an excess of total fat (30%) and fructose (20% solution instead of drinking water), or the same diets supplemented with RC in a low (25 mg/kg body weight as resveratrol and 300 mg/kg as L-carnitine) or high (50 and 600 mg/kg body weight, respectively) doses. The expression of genes (Khk, Gck, Pklr, Acaca, Acacb, Fasn, Scd, Srebf1, Mlxipl, Ppara, Pparg, Actb, Gapdh) in liver cells was studied by the method of real-time reverse transcription polymerase chain reaction (RT-PCR). The distribution of tyrosine aminotransferase (TAT), nuclear factor erythroid 2-related factor 2 (NRF-2) and intercellular adhesion molecule type 2 (ICAM-2) in the liver and kidneys was assessed by confocal laser microscopy and immunohistochemistry. Results. Increased expression of Fasn (fatty acid synthase) in rats treated with high-fat high-carbohydrate diet (HFCD) decreased under RC intake. RC consumption caused a decrease in the number of TAT-, NRF-2- and ICAM-2-positive cells in the liver of rats treated with HFCD, but had the opposite effect in the kidneys. The consumption of RC at the low dose by rats fed HFCD caused changes in the expression profiles of the studied marker genes, indicating a possible hypolipidemic effect. However, observed increased expression of lipogenic genes in the liver and elevated level of NRF-2 and ICAM-2 in kidney against the background of consumption of RC with the standard balanced diet cannot be assessed as unambiguously positive. Conclusion. Thus, possible negative effects caused, most likely, by the interaction of nutraceuticals with various mechanisms of action should be taken into account when developing formulations of dietary supplements and foods for special dietary uses for dietary therapy of obesity.

The need to improve existing and develop new effective technologies for processing metal materials by pressure (including those with severe plastic deformations that make it possible to obtain products with an ultrafine-grained structure), constantly increasing requirements for the accuracy of strength calculations, emerging new materials with complex properties (including gradient materials), the need to design and create functional materials require mechanicians and material physicists to constantly work on constitutive models (constitutive relations) to describe the behavior of various materials. In this case, the models used to describe the processes of thermomechanical processing attract the greatest interest, since it is such models that the main performance characteristics of finished products are formed. The physical and mechanical characteristics (including strength) of the materials of the products are determined mainly by the microstructure formed as a result of processing. In this regard, the most popular are the models that allow explicitly describing the evolving microstructure of various structural and scale levels. At the same time, currently, the most common among specialists in the field of solid mechanics, technologists, and engineers are macrophenomenological constitutive relations based on processing the results of macro experiments and not using an explicit description of the material structure. Along with the constitutive relations of this class, in the last 15–20 years, multilevel models based on the introduction of internal variables and physical theories of elastoplasticity (elastoviscoplasticity) are gaining wider acceptance for analyzing the behavior of materials under thermomechanical (and more complex, for example, radiation) effects. In this article, we have made an attempt to compare the advantages and disadvantages of the models of these classes, assess the areas of their applicability, as well as formulate some problematic questions, answers to which the author have not found in the existing literature on mechanics of solids and materials science.

BACKGROUND: Quercetin (Q; 3,3',4',5,7 - pentahydroxyflavone) can help alleviate the pathological effects of nutritional obesity and metabolic syndrome when taken as part of products for special dietary needs and food supplements. The mechanisms of action of Q at the genetic level are not well understood.AIMS: To study gene expression in liver tissue of mice with alimentary and genetically determined obesity upon intake of Q with diet.MATERIALS AND METHODS: During 46 days of the experiment on 32 male C57Bl/6J mice fed a diet with an excess of fat and fructose and 24 male genetically obese db/db mice the effect of Q in dose of 25 or 100 mg/kg of body weight was studied on differential expression of 39430 genes in mice livers by full transcriptome profiling on microchip according to the Agilent One-Color Microarray-Based Gene Expression Analysis Low Input Quick Amp Labeling protocol (version 6.8). To identify metabolic pathways (KEGGs) that were targets of Q exposure, transcriptomic data were analyzed using bioinformatics methods in an “R” environment.RESULTS: Differences were revealed in the nature of Q supplementation action in animals with dietary induced and genetically determined obesity on a number of key metabolic pathways, including the metabolism of lipids and steroids (Saa3, Cidec, Scd1, Apoa4, Acss2, Fabp5, Car3, Acacb, Insig2 genes), amino acids and nitrogen bases (Ngef, Gls2), carbohydrates (G6pdx, Pdk4), regulation of cell growth, apoptosis and proliferation (Btg3, Cgref1, Fst, Nrep Tuba8), neurotransmission (Grin2d, Camk2b), immune system reactions (CD14i, Jchain, Ifi27l2b).CONCLUSIONS: The data obtained help to explain the ambiguous effectiveness of Q, like other polyphenols, in the dietary treatment of various forms of obesity in humans, as well as to form a set of sensitive biomarkers that allow us to elucidate the effectiveness of minor biologically active food substances in preclinical trials of new means of metabolic correction of obesity and metabolic syndrome.

The development of new and improvement of existing modes of thermomechanical treatment of metals and alloys in present conditions is impossible without development of appropriate mathematical models, that allow determining material characteristics during technological processes. Constitutive equations are the core, the main components that determine the quality of such models. Macrophenomenological theories of plasticity relying on processing the results of experiments on macrosamples, have become widespread as such in solving applied problems of solid mechanics. Taking into account the need to describe the memory of processes, the equations of this class have a complicated mathematical structure, require expensive tests (generally speaking, for complex loading) for each material, due to which they are not universal. In the past 15-20 years, constitutive models based on the introduction of internal state variables, of a multilevel approach, and physical theories of inelasticity (plasticity, viscoplasticity) became very popular. Models of this class are focused on describing the evolving structure (including microstructure), which ultimately determines the physical and mechanical properties of materials and constructions. As the physical mechanisms and their carriers are identical for wide classes of materials, the models of this class have significant versatility, including the prediction of behavior of new, not yet existing materials, to study the physical mechanisms of the occurrence of various effects, observed in macro experiments. Hardening is one of interesting effects observed in experiments on complex (including cyclic) loading (as compared to directional loading) of samples, made of various metals and alloys, arising from a significant evolution of the microstructure. Empirical data analysis made it possible to establish that the tendency to manifest this effect is usually experienced by metals and alloys with a low stacking fault energy (SFE). The paper provides a brief analysis of the experimental work and mathematical models describing the response of a material to complex deformation. It is noted that macrophenomenological theories do not allow one to describe in an explicit form the evolution of the microstructure and the carriers of plastic deformation and hardening mechanisms, thus they do not provide an opportunity to explain the physical reasons for the above effects. The purpose of this work is to develop, study and implement a multilevel elasto-visco-plastic model that allows describing the evolution of crystal lattice defects in materials with different SFE under different thermomechanical processing, different strengthening mechanisms at different structural-scale levels. In the framework of constructing a constitutive model, special attention is paid to the development of a submodel, focused on description of the evolution dislocations and barrier densities on slip systems. Kinetic equations for dislocation densities on slip systems make it possible to analyze the nucleation of dislocations due to the activation of Frank - Read sources, annihilation of dislocations of different signs on one slip system, interaction of split dislocations of intersecting slip systems with the formation of barriers. Relations for the description of hardening are given, taking into account the current density of dislocations and barriers. The general structure of the model and the relationship between the parameters of submodels of different levels are considered. An algorithm and a program of implementing the model were developed, the evolution of dislocation densities on slip systems was analyzed, and the intensity of hardening and the formation of barriers on split dislocations were obtained depending on the type of loading.

Wide opportunities of using fine-grained materials as structural and functional materials with advanced physical and mechanical properties have proved the importance of improving the existing technology and creating new processing methods and treatment conditions for such ma-terials. At the same time, a preliminary theoretical analysis using mathematical models gives an opportunity to significantly reduce the cost of such experimental studies. Thus, it is necessary to develop multilevel models of polycrystalline metals and alloys based on crystal plasticity with the description of structure, deformation mechanisms and refinement at various scale levels. To con-struct a correct model of such a class, it is necessary to analyze information and arrange a large amount of experimental data about grain structure refinement. The article presents a review of the experimental studies describing and analyzing the grain structure refinement during severe plastic deformations of various metal alloys. The refine-ment mainly occurs at low temperatures that are a priori lower than the temperatures at which re-crystallization becomes an important factor and the solid-state phase transitions may take place. We have summarized the significant physical mechanisms of the grain refinement during cold deformation based on the arranged experimental data from the review. All the considered articles pay attention to the local accumulation of lattice dislocations inside the grains (in the form of flat clusters), which leads to the lattice curvature and separation of grains into cells. As a result of a further accumulation of dislocations in the walls, there comes an increase in misorientation of the neighboring cells. The curved lattice is unstable (it seems clear that the flat clusters become a source of such curvatures) and relaxes with the formation and movement of the partial disclina-tions, which leads to the rotation of the adjacent grain regions and creation of new grain bounda-ries. In addition, the mesoscale defects located at the junctions of the grains (including the boundary intersection disclinations), flat clusters of the dislocations of the orientational mismatch at the grain boundaries and partial dislocations in the grains have a significant effect on the frag-mentation. The articles about the severe plastic deformation at high temperatures are briefly de-scribed here. It is noted that recrystallization is the main mechanism of the fine-grained structure formation under these conditions. We suggest including the description of the discussed mechanisms in the multilevel con-stitutive material models. When new experimental data appear for a specific process of the severe plastic deformation, the considered refinement mechanisms can be added.

Deep wounds of the scalp of various origins (mechanical trauma, animal bites, burns) are quite common in pediatric practice. Defects of soft tissues, the bottom of which has open bones, are a particular difficulty. This clinical observation describes a method of surgical treatment of a deep wound of the scalp using the tissue expansion, which leads at one time to the complete closure of the soft tissue defect in combination with an excellent cosmetic result. The relative simplicity and safety of the technique can cause its widespread use in pediatric reconstructive surgery and burn surgery.

Nanoheterostructures based on titanium, vanadium, molybdenum, and tungsten oxides assembled in the form of microspheres have been synthesized. Their structural and photoelectronic properties have been studied. It has been shown that the photocatalysis rate increases significantly for microspheres consisting several metal oxides. A relation of the photocatalysis rate to the number of V4+ paramagnetic centers and the time of their relaxation after the end of illumination has been revealed. It has been found that the spatial separation of photoexcited charge carriers between different nano-oxides in heterostructures leads to the accumulation of charge in them and to prolonged catalysis. Consequently, they are promising for application as the main material of photocatalytic filters for cleaning the environment.

In this study, nonstoichiometric hafnium carbonitrides (HfCxNy) were fabricated via short-term (5 min) high-energy ball milling of Hf and C powders, followed by combustion of mechanically induced Hf/C composite particles in a nitrogen atmosphere (0.8 MPa). The obtained HfC0.5N0.35 powder exhibited a rock-salt crystal structure with a lattice parameter of 0.4606 nm. The melting point of this synthesized ceramic material was experimentally shown to be higher than that of binary hafnium carbide (HfC). The nonstoichiometric hafnium carbonitride was then consolidated under a constant pressure of 50 MPa at a temperature of 2000 °C and a dwelling time of 10 min, through spark plasma sintering. The obtained bulk ceramic material had a theoretical material density of 98%, Vickers hardness of 21.3 GPa, and fracture toughness of 4.7 MPa m1/2.

We studied the effects of quercetin (Q) on the behavioral responses and integral and metabolic indices in male db/db mice genetically predisposed to obesity and C57Bl/6J mice fed a diet with an excessive energy value. We examined forepaw grip strength, exploratory activity, anxiety, and short-term memory, as well as integral and biochemical indices, and the contents of leptin, ghrelin, and IL-10. We found differences between two models of obesity in the integral and biochemical indices and behavioral responses to Q treatment. In the db/db mice, they were associated with knockout of the Lepr gene encoding the leptin receptor, which prevented the neurotropic and regulatory functions of leptin. These effects of Q detected should be considered when justifying the dose and timing of this nutraceutical in clinical practice.

Nanostructured mechanical composites of immiscible metals Cu, Cr, and 5–70 wt % W; nanostructured consolidated materials based on them; and Cu/Cu–Cr–W nanostructured gradient material with various W contents are fabricated in this work by combining short-term (up to 150 min) high-energy ball milling (HEBM) and spark plasma sintering (SPS). To fabricate Cu–Cr–W mechanical composites, HEBM of Cu + Cr + (5–70 wt %)W is performed using an Activator-2S planetary ball mill with a revolution rate of drums of 1388 rpm and a planetary disc of 694 rpm in argon for 150 min. The Cu–Cr–W mechanical composites are consolidated by SPS at temperatures of 800–1000°C and pressure of 50 MPa for 10 min. The nanostructured gradient sintered material based on Cu–Cr–W pseudoalloys is compacted layer-by-layer in the following sequence (from pure copper to pseudoalloy with an increase in the tungsten weight fraction): Cu/Cu–Cr–5% W/Cu–Cr–15% W/Cu–Cr–70% W and sintered at 800°C for 10 min. The crystal structure, microstructure, and properties of Cu–Cr–W mechanical composites and consolidated materials based on them are investigated depending on fabrication conditions. It is shown that the nanostructure formed in mechanical composites at the short-term HEBM stage (up to 150 min) is retained after SPS for all Cu–Cr–W (5–70 wt % W) compositions. The SEM and EDS data evidence that W (d ~ 20–100 nm) and Cr (d ~ 20–50 nm) refractory particles are homogeneously distributed in the material bulk (in a copper matrix). The hardness of consolidated Cu–Cr–W samples (15 wt %) formed from nanostructured powder mixtures (after 150-min HEBM) by SPS at t = 800°C exceeds the hardness of samples sintered from the mixture of initial components (without HEBM) by a factor of ~6. The hardness for the nanostructured Cu–Cr–70% W composition (tSPS = 1000°C) is higher by a factor of ~3 than for microcrystalline analogs. Samples Cu–Cr–15% W and Cu–Cr–70% W have the largest relative density up to 0.91. The resistivity of nanostructured Cu–Cr–W compositions exceeds this characteristic for microcrystalline samples approximately twofold. This can be caused by an increase in grain boundaries and the accumulation of various defects in the material at the HEBM stage. These results show the prospects of using the combination of short-term HEBM and subsequent SPS for the formation of consolidated nanocrystalline Cu–Cr–W composites and gradient materials based on them.

We present a problem described by Mean Field Games (MFG) and Optimal Control theory on finite time horizon. This problem consists of a system of PDEs: a Kolmogorov–Fokker–Planck equation, evolving forward in time and a Hamilton–Jacobi–Bellman equation, evolving backwards in time. The numerical difficulties are based on a turnpike effect considered in this paper. We present an extremal problem whose necessary conditions of extremal satisfy the initial system of PDEs, and introduce its numerical solution at the heart of monotonic schemes. According to special assumptions, PDEs can be reduced to Riccati ODEs. We consider this reduction as a test example for the numerical solution of the extremal problem.

Control over the inelastic deformation of polycrystals aimed at achieving desired performance characteristics of finished products is impossible without analyzing the structural evolution of the material at different scale levels. A major task in this respect is to develop physically sound mathematical models for describing the internal structure evolution as it determines the material properties. An effective tool for addressing this task is a multilevel approach to describing the thermomechanical processing of crystalline materials, in which carriers and physical mechanisms of processes are considered explicitly. Thermomechanical processing allows a good control over the defect and grain/subgrain structure of the material to achieve desired macrocharacteristics. This paper explores the subgrain/grain structure evolution during static recrystallization that occurs through strain-induced boundary migration. Modeling is carried out in two stages. The first stage models the plastic deformation of a crystalline material at room temperature. The second stage considers holding at an elevated temperature resulting in recrystallization. Both stages are modeled within a unified multilevel approach. The problem of modeling static recrystallization is formulated, and an algorithm for its numerical implementation is described. The modeling results are obtained for a bicrystal in which each grain is represented by a group of lower-scale elements (subgrains). Recrystallization causes profound changes in the subgrain structure geometry, the average size of subgrains, and their shape change. Recrystallized subgrains are more elongated compared to the original ones. During recrystallization more defective grains are replaced with less defective grains, and as a result the energy stored in the material decreases. The developed model qualitatively describes the release of stored energy. Numerical experiments revealed a critical plastic strain value below which recrystallization does not occur.