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Abstract To date, pulmonary fibrosis remains an unmet medical need. In this study, we evaluated the potency of mesenchymal stromal cell (MSC) secretome components to prevent pulmonary fibrosis development and facilitate fibrosis resolution. Surprisingly, the intratracheal application of extracellular vesicles (MSC-EVs) or the vesicle-depleted secretome fraction (MSC-SF) was not able to prevent lung fibrosis when applied immediately after the injury caused by bleomycin instillation in mice. However, MSC-EV administration induced the resolution of established pulmonary fibrosis, whereas the vesicle-depleted fraction did not. The application of MSC-EVs caused a decrease in the numbers of myofibroblasts and FAPa+ progenitors without affecting their apoptosis. Such a decrease likely occurred due to their dedifferentiation caused by microRNA (miR) transfer by MSC-EVs. Using a murine model of bleomycin-induced pulmonary fibrosis, we confirmed the contribution of specific miRs (miR-29c and miR-129) to the antifibrotic effect of MSC-EVs. Our study provides novel insights into possible antifibrotic therapy based on the use of the vesicle-enriched fraction of the MSC secretome.

Three-dimensional scaffolds were made from a solution of poly(lactide-co-glycolide) mixed with tetraglycol using antisolvent 3D printing. The elastic properties and the structure of the obtained matrices were studied. MTT-test and staining with PKH-26, Calcein-AM, DAPI with subsequent fluorescence microscopy were used to study biological properties. The three-dimensional scaffolds had good mechanical properties. Young’s modulus value was 18±2 MPa, tensile strength was 0.43±0.05 MPa. The relative survival rate of cells after the first day was 99.58±2.28%, on the 14th day – 98.14±2.22%. The structure of the scaffold promoted cell adhesion and spreading on its surface. The poly(lactide-co-glycolide) matrices produced by antisolvent printing have high porosity, biocompatibility and good mechanical properties. It is allowed to use them in the future as a basis for personalized constructions for the replacement of extensive bone defects.

In this work, polycrystalline samples of hard-magnetic materials of (Nd1– xPrx)2Fe14B general formula have been prepared and subjected to severe plastic deformation (SPD). Thereafter the features of nanostructure formation in the compounds were investigated before and after SPD using atomic force microscopy and magnetic force one (AFM & MFM). The differences in texture formation were revealed when studying the surface microstructure of both the initial and deformed samples. The initial ones prepared by the Czochralski method, exhibited the columnar structure, while the SPD samples exhibited the concentric rings containing elongated nanosized crystallites. The magnetic domain structure was visualized using the MFM that clearly demonstrated the relationship between the microstructural features and the magnetic domains’ configuration.

Analysis of the applicability of wave model solution to evaluate the variation of the dynamic stiffness in the pile foundation versus the distance between piles at the vertical vibrations; both experimental data from references and our own measurements in field are involved. To justify the reliability of the solutions of the wave models used to determine the dynamic stiffness values of the pile foundations at the vertical vibrations, we use the data obtained experimentally for the determination of natural frequencies in the cap-bound groups. The data obtained for the natural frequencies of 3×3 floating piles with different distances between them are considered. In addition, the data found at the forced vertical vibrations of the cap-bound groups of 2×2 piles under different loads and at different distances between the piles are involved. Processing of available amplitude-frequency curves involves the solution of the inverse problem with the theory of nonlinear vibrations to determine the parameters of the “pile group – soil” system, namely the effective mass, stiffness, and damping. The correlation between the measured and predicted data is evaluated by using the data obtained at the description of the pile groups in soil behavior. It has been found that the relations obtained at the solution of wave models and used to calculate the dynamic stiffness at the vertical vibrations of pile foundations consider the mutual effect of the piles in the group and permit satisfactory accuracy of the results. The maximum discrepancy between the results and experimental data is 15 %.

The materials of the article are devoted to the issues of ecology and safety at enterprises and railway transport. The urgency of developing a universal kit for rapid detection of aggressive chemicals, rocket fuel components and uranium compounds in various environments is due to the fact that the presence on the surface and in water can lead to poisoning and chemical burns of working personnel and the public. It is also caused by the need to make managerial decisions when eliminating the consequences of accidents at food and related industries. The article discusses the methods of rapid detection of aggressive chemicals and suggests scientific, methodological and technological approaches to the development of a universal set of tools for group rapid detection of aggressive chemicals and uranium compounds in water and on the surfaces of objects using aerosol devices with original indicator formulations. The place of research is Moscow and the Moscow region

The article studies the influence of the level and type of reinforcement of bending elements of reinforced concrete structures on their bearing capacity under the influence of alternating freezing and thawing. Strength and deformation characteristics for B30 concrete class were taken according to Construction Rules SP 63.13330.2018, and after exposure to alternating freezing and thawing according to Construction Rules SP 52.105.2009. The study of the stress-strain state and the assessment of the bearing capacity were carried out according to a specially developed program, in which the diagrammatic method was implemented. It is shown that the durability of bent reinforced concrete structures depends on the percentage and type of reinforcement. When reinforcing with longitudinal tensile reinforcement equal to 1%, the decrease in the bearing capacity of a reinforced concrete beam after exposure to alternating freezing and thawing will make up 5.5%, and in case of 2.5% reinforcement it will equal to 20.9%. In addition, the nature of fracture will change and the stress in the tensile reinforcement will not reach the design resistance. If it is impossible to limit the percentage of reinforcement of longitudinal tensile reinforcement, it is recommended to use double reinforcement. Installation of working reinforcement in a compressed zone in a volume of 50% of the stretched one with a reinforcement percentage of 2% will reduce the decrease in bearing capacity to 2.2% after exposure to freezing and thawing cycles and not change the nature of destruction.

The authors consider the problems concerned with the mathematical constituent of implementation of interdisciplinary semester projects by groups of students. Significance of using the method of projects for creation of the innovative environment in a technical university, as well as for formation of professional competences of future engineers is demonstrated. The authors have analyzed the techniques of student groups’ work on term projects and reflected the role of a teacher in the process of implementation of such projects. It is stressed that one of the major components of technical university education is fundamental training of engineering students based on deeper and wider cycle of mathematical and common engineering disciplines. It provides close interdisciplinary relations between the mathematics course and engineering disciplines, increases the motivation to master mathematics, helps the students to recognize the need to gain profound mathematical knowledge, and forms the skills of creative application of the gained knowledge to successful mastering their engineering professions chosen. It is demonstrated that, in a technical university, an interdisciplinary term project is in essence a task that unites various scientific and technical disciplines and demands engineering and technical knowledge as well as mathematical methods of task solution: applied methods of mathematical modeling, methods of probabilistic and statistical analysis of data, and various types of mathematical packages.

The article provides data on the flora of the former Southern Solid Waste Landfill in St. Petersburg. A rather unique partial flora and specific anthropogenic vegetation has formed at the landfill, in which weed and exotic species of higher plants significantly quantitatively predominate over native species (approximately 68 % to 32 %). As for the mass character of the plants themselves, in a number of cases the amount of adventive species reached 99 %. A large number of rare alien species were identified as part of the flora of the landfill, including such as Punica granatum, Vitis vinifera, Melo vulgaris, Citrullus vulgaris, Phytolacca americana, Glycine max, Physalis species, etc. that do not fall of cultivation in the North-Easter Russia because of their thermophyte nature. The article contains a list of plant taxa identified at the city landfill site during a survey of adventive flora in July-August 1999, including 179 species from 36 families of flowering plants, of which 122 species are alien. The main aboriginal species we encountered are also given. Despite the fact that the survey was conducted almost 20 years ago, over the past years, no new data on the composition of the flora and its dynamics has been published on large landfills and solid waste landfills in St. Petersburg, in connection with which we publish these materials. The data obtained by us can serve as the basis for studying dynamics of flora in such unique habitats.

The aim of this study was to evaluate the allelopathic effect of cold aqueous extracts, both fresh and dry biomass of dodder (Cuscuta epithymum L.) on lucerne (Medicago sativa L.) and bird’s foot-trefoil (Lotus corniculatus L.). Four different varieties of lucerne “Pleven 6”, “Dara”, “Roly”, “Multifoliolate”) and bird’s foot-trefoil (“Gran San Gabriele”, “Leo”, “Local population 1”, “Local population 2”) were studied in order to find some varieties with allelopathic tolerance. Ex-situ experiment was carried out as follows: 100 seeds of each variety were put in Petri dishes between filter paper, both cold extracts of parasitic weed biomass were pipetted at a ratio of 1:20 as against the seed mass and then were placed in a thermostat-operated device at a temperature of 22 ± 2°С. Distilled water was used as a control. Percentage inhibition, Index of tolerance and Index of plant development were calculated for assessment of the allelopathic effect of dodder on the early seedling growth, biomass synthesis and initial development of experimental varieties. As a whole, dry weed biomass was found as more toxic for the tested plants than the fresh one. Medicago sativa var. multifoliolate and Lotus corniculatus var. Local population 1 and Local population 2 showed a significant tolerance to the allelopathic influence of Cuscuta epithymum in all studied concentrations of aqueous extract of fresh weed biomass (25, 50 and 100 g l−1) and medium tolerance to aqueous extract of dry weed biomass (concentrations of 25 and 50 g l−1).

During the 2014-2016 period in Agroecological Center at the Agricultural University - Plovdiv, Bulgaria growth and development of three species of wheat in terms of organic farming had been tracked in order to return the species in the crop rotation, maintenance of biodiversity and receiving of cleaner and healthy products from organic farms. The three species of wheat Triticum monococcum L., Triticum dicoccum Sch, and Triticum spelta L., differ between its rate of growth, development, general and productive tillering. In tillering phase the plants reached 12,3 cm of height for Triticum monococcum L., 15,7 cm for Triticum spelta L. and 19,4 cm for Triticum dicoccum Sch. Triticum monococcum L. and Triticum dicoccum Sch, reached ear formation phase 5 days earlier than Triticum spelta L. The interfacial period of stem elongation - ear formation in them, was about 21 days compared to 25 days for Triticum spelta L.. From ear formation to full maturity inter-phase periods were shorter in Triticum dicoccum Sch., which specifies the species as an early mature (6 days earlier) compared to the other two. After phenophase of stem elongation plants were growing the most intensive and in full ripeness reached a height of 94 cm in Triticum monococcum L., 81,5 cm in Triticum dicoccum Sch. and 82,5 cm in Triticum spelta L.

Bulk Mn52Al46C2 in τ-phase was prepared by vacuum induction melting and used as precursor for the production bulk permanent magnets by suction casting and hot-extrusion. Part of the precursor alloy was mechanically milled into a τ-phase powder and used as precursor for production of samples by electron beam melting, hot-compaction and high pressure torsion processes. The microstructure and magnetic properties of all samples were investigated and correlated. It was found that the mechanical deformation enhances coercivity, up to 0.58 T, while the absence of this strain is beneficial for magnetization. Among the observed techniques, hot extrusion and high pressure torsion have shown promising possibilities to further develop Mn-Al-C as permanent magnets. However, it should be taken into account the challenges related to design a proper processing window for hot extrusion and the limitation of HPT regarding the absence of texture.

The article discusses the acquisition of environmental and related digital competencies in the training of engineering specialists of different levels. Provides data on current trends in education. The approaches to basic, universal and general technical competencies, and their relationship with digital competencies are considered. When working with expert opinions, the necessary, in the opinion of the expert community, environmental and digital competencies that are relevant in modern conditions are identified. Based on these results, changes were proposed to the work program for the discipline related to ensuring environmental safety on the one hand and digital competencies on the other. Based on a review of modern approaches, a survey of experts and work with new generation work programs, conclusions were drawn about the advisability of continuing research in this direction, as well as the implementation of digital competencies in the field of environmental education.

One of the technological innovations nowadays is the development of industrial processing of agricultural raw material, manufacturing process leading to lower risks – «Low/No/Reduced» and «Better-for-you». This may be done by light processing of raw materials and use of traditional technologies, i.e. fermentation of craft beverages by natural symbiotic cultures Oryzamycesindichiand Medusomycesgisevi (kombucha). The recent years saw a worldwide interest to a horticultural crop called Hippophaerhamnoides (sea-buckthorn) as it is eco-friendly and healthful. Its fruits have a special smell and taste, are reach in carotene, carotenoids, tocopherols, ascorbic acids, polyphenols. The composition is the reason why it is used for foodstuff, i.e. pastry, dairy products, unclarified juice. Production of beverages fermented by natural symbiotic cultures and local orchard products is a new direction in Russia. The supplies are limited which means that the research is relevant. The aim of the research is to study the possibility of usage ofjuice of Hippophaerhamnoides fruits in the new technology of soft drinks production fermented by Oryzamycesindichi and Medusomycesgisevi. A single nutritious substrate for Oryzamycesindichi and Medusomycesgisevi symbiotic cultures cultivation was proved impossible to be produced. Still the possibility to replace polyphenols of the Medusomycesgisevi by those of the sea-buckthorn juice must be analyzed.Sea-buckthorn juice added in a culture medium fermented by Oryzamycesindichi and Medusomycesgisevi symbiotic cultures increases biosynthetic activity of acidforming bacteria. This tangibly improves organoleptic properties of the fermented soft beverages produced. Besides, the technology of Oryzamycesindichi and Medusomycesgisevi production presupposes no clarification which makes the process of the Hippophaerhamnoides use significantly easier. The research helped to identify that the sea-buckthorn juice used in a must fermented by Medusomycesgisevi has many advantages. Namely more comprehensive utilization of carbohydrate, a higher level of reduction of organic acids, and decrease of the time of technological process (24 hours less).

This paper is devoted to the study of persistence and evolution of two viruses taking into account virus mutation, reproduction, and genotype dependent mortality, either natural or determined by an antiviral treatment. The model describes the virus density distribution u(x; t) for the first virus and v(y; t) for the second one as functions of genotypes x and y considered as continuous variables and of time t. The model consists of a system of reaction-diffusion equations with integral terms characterizing virus competition for host cells. The analysis of the model shows the conditions of the existence of virus strains.

Hybrid additive manufacturing is a relatively modern trend in the integration of different additive manufacturing techniques in the traditional manufacturing production chain. Here the AM-technique is used for producing a part on another substrate part, that is manufactured by traditional manufacturing like casting or milling. Such beneficial combination of additive and traditional manufacturing helps to overcome well-known issues, like limited maximum build size, low production rate, insufficient accuracy, and surface roughness. The current paper is devoted to the classification of different approaches in the hybrid additive manufacturing of steel components. Additional discussion is related to the benefits of Powder Bed Fusion (PBF) and Direct Energy Deposition (DED) approaches for hybrid additive manufacturing of steel components.

The antimicrobial activity of nanoparticles (NPs) depends of the surface area in contact with microorganisms. The large surface area of the nanoparticles enhances their interaction with the microbes. In this work, a green, simple, rapid, and efficient ultrasound-assisted reduction method for silver nanoparticles (AgNP) synthesis is presented. For the synthesis, an aqueous solution of silver nitrate, ethanol, and ammonia was used. The adopted method can be easily implemented for any kind of scientific or industrial application due to its cost-effective nature. The effect of sonication time on the nanoparticle formation was investigated. Silver nanoparticles were analyzed through transmission electron microscopy and UV-vis spectroscopy. Antimicrobial additives can be incorporated in mass in different matrixes (polymeric or cellulosic), which is a convenient methodology to achieve antimicrobial activity. In this work, silver nanoparticles were incorporated in cellulose using an ultrasonic bath technique. The most important aspect of cellulose containing silver nanoparticles prepared by this method is its high antimicrobial efficiency. The microbiological study was carried out by a standard agar technique. The analysis showed that cellulose with incorporated silver nanoparticles exhibited strong antimicrobial activity against Escherichia coli bacteria. This makes it a promising antibacterial material for food packaging.

This article experimentally proves the negative (destructive) effect of chloride DIR on railway transport facilities. The ways of chloride DIR getting of various objects of railway transport are shown. The relationship between the usage of chloride DIR and the violation of traffic safety in railway transport is being proven. Possible scenarios of the occurrence of a violation of traffic safety without taking into account the occurrence of human casualties are presented.

The current paper is devoted to classification of powder-bed additive manufacturing (PB-AM) techniques and description of specific features, advantages and limitation of different PB-AM techniques in aerospace applications. The common principle of “powder-bed” means that the used feedstock material is a powder, which forms “bed-like” platform of homogeneous layer that is fused according to cross-section of the manufactured object. After that, a new powder layer is distributed with the same thickness and the “printing” process continues. This approach is used in selective laser sintering/melting process, electron beam melting, and binder jetting printing. Additionally, relevant issues related to powder raw materials (metals, ceramics, multi-material composites, etc.) and their impact on the properties of as-manufactured components are discussed. Special attention is paid to discussion on additive manufacturing (AM) of aerospace critical parts made of Titanium alloys, Nickel-based superalloys, metal matrix composites (MMCs), ceramic matrix composites (CMCs) and high entropy alloys. Additional discussion is related to the quality control of the PB-AM materials, and to the prospects of new approaches in material development for PB-AM aiming at aerospace applications.

The article shows that inflation could be controled in the consumer market through reducing its rates and reducing inflation risks. The approach lies in consideration of risks of ingredients of the consumer choice as a component of a common consumer basket and not that of individual units. The level of correlations of price growth of goods of consumer choice lies in the centre of attention of the offered strategy of control. It is necessary to note that realisation of such measures as regulation of consumer demand and purposeful change of the structure of consumption – is a task, which could be solved only within the framework of the state policy. The state should use its power in the field of taxation, expenditures and monetary policy when eliminating economic instability.Показано, что инфляцией на потребительском рынке можно управлять, снижая ее темпы и уменьшая инфляционные риски. Сущность подхода заключена в том, чтобы рассматривать риски ингредиентов потребительского набора, как составляющую единой потребительской корзины, а не отдельно взятых единиц. В центре внимания предлагаемой стратегии управления находится уровень корреляций ценовых ростов товаров потребительского набора. Необходимо отметить, что реализация таких мер, как регулирование потребительского спроса, целенаправленное изменение структуры потребления ? это задача, которая может быть решена только в рамках государственной политики. Государство должно использовать свою власть в области налогообложения. расходов и денежной политики при устранении экономической нестабильности.

The main role of milk and milk products in the technology of confectionery products (chocolates, caramele-candy products, dairy products, spreads, etc.) is to increase the nutritional value of the final product and to influence some sensory characteristics of quality (appearance, consistence/texture, flavor). In this study, mixtures of milk and cocoa spreads of a new composition with increased content of milk components were produced, and then assessed for sensory quality traits, peroxide value, free fatty acid content and the content of heavy metals (lead, cadmium and copper) during storage from 0-30 to 180 days at room temperature (18 - 20ºC). The samples were evaluated using the analytical-descriptive sensory analysis (point system) with description of the dominant properties (appearance-color, surface gloss, consistence-spreadability, dynamic property of melting, the consistence in the oral cavity-oiliness and flavor-odor and taste). The results of sensory analysis were statistically analyzed using two-way analysis of variance MANOVA, LSD and Levene's test. Based on the obtained results it can be concluded that the composition of mixtures of milk and cocoa spreads significantly affects all characteristics, whereas the storage time significantly affects the appearance, consistence, i.e. spreadability and taste of the product.

The paper deals with the problems of mathematical modeling of the dynamic processes proceeding in a complex hydromechanical system of the ship’s deck load-lifting devices. The characteristic feature of this class of equipment is the operation in special conditions, i.e, under the influence of external hydrometeorological factors, taking into account variations in the parameters of lifted or lowered cargo. With a view to gradual regulation of the change of torque on the working drum to reduce dynamic loads, it is offered to use a hydraulic drive that is sensitive to the variation of loading. The operating principle of the considered volumetric hydraulic drive is described. The received mathematical model allows to establish influence of the hydrodrive parameters on transients in a drive system.

The volumes of freight and passenger traffic on the railways of the Russian Federation are increasing every year. Along with the increase in the transportation work, the likelihood of occurrence of undesirable incidents in railway transport increases. The assessment of the level of comprehensive (integrated) safety is an important scientific and technical problem in the current conditions of the functioning of railway transport. The methods used to assess the level of safety do not always meet the requirements of complexity in view of comparison of various-scale violations of traffic safety (crash, accident, faulty operation). The paper proposes a mathematical method for assessing the level of integrated safety in railway transport and calculation of the safety index of train traffic. For the calculation, statistical data for a certain period are used. These data summarized in a specialized dictionary of traffic safety violations, the mathematical treatment of which provides information on the level of integrated safety in railway transport in the Russian Federation. The proposed index allows determining the effectiveness of management decisions in the field of train traffic safety, as well as assessing the effectiveness of implementing certain innovations in the field of traffic safety. It is possible to use data on integrated traffic safety to reduce insurance premiums for cargo insurance on railways.

Structure, magnetic and magnetoresistive properties of spin valves with Ni-Fe-Mn antiferromagnet as a pinning layer have been studied. A technique of fabrication of spin valves with an enhanced thermal stability and improved hysteretic characteristics has been elaborated.

Abstract Epigenetic modifications play a key role in the patho-physiology of many tumors and the current use of agents targeting epigenetic changes has become a topic of intense interest in cancer research. DNA methyltransferase (DNMT) inhibitors represent a promising class of epigenetic modulators. Research performed yielded promising anti-tumorigenic activity for these agents in vitro and in vivo against a variety of hematologic and solid tumors. These epigenetic modulators cause cell cycle and growth arrest, differentiation and apoptosis. Rationale for combining these agents with cytotoxic therapy or radiation is straightforward since the use of DNMT inhibitor offers greatly improved access for cytotoxic agents or radiation for targeting DNA-protein complex. The positive results obtained with these combined approaches in preclinical cancer models demonstrate the potential impact DNMT inhibitors may have in treatments of different cancer types. Therefore, as the emerging interest in use of DNMT inhibitors as a potential chemo- or radiation sensitizers is constantly increasing, further clinical investigations are inevitable in order to finalize and confirm the consistency of current observations. The present article will provide a brief review of the biological significance and rationale for the clinical potential of DNMT inhibitors in combination with other chemotherapeutics or ionizing radiation. The molecular basis and mechanisms of action for these combined treatments will be discussed herein.

We report a computational study of the bending deformation of two-dimensional nanoribbons by classical molecular dynamics methods. Two-dimensional double transition metal carbides, together with monometallic ones, belong to the family of novel nanomaterials, so-called MXenes. Recently, it was reported that within molecular dynamics simulations, Ti 4 C 3 MXene nanoribbons demonstrated higher resistance to bending deformation than thinner Ti 2 C MXene and other two-dimensional materials, such as graphene and molybdenum disulfide. Here, we apply a similar method to that used in a previous study to investigate the behavior of Mo 2 Ti 2 C 3 nanoribbon under bending deformation, in comparison to the Ti 4 C 3 sample that has a similar structure. Our calculations show that Mo 2 Ti 2 C 3 is characterized by higher bending rigidity at DTi2Mo2C3≈92.15 eV than monometallic Ti 4 C 3 nanoribbon at DTi4C3≈72.01 eV, which has a similar thickness. Moreover, approximately the same magnitude of critical central deflection of the nanoribbon before fracture was observed for both Mo 2 Ti 2 C 3 and Ti 4 C 3 samples, wc≈1.7 nm, while Mo 2 Ti 2 C 3 MXene is characterized by almost two times higher critical value of related external force.

Non-axisymmetric frictionless JKR-type adhesive contact between a rigid body and a thin incompressible elastic layer bonded to a rigid base is considered in the framework of the leading-order asymptotic model, which has the form of an overdetermined boundary value problem. Based on the first-order perturbation of the Neumann operator in the Dirichlet problem for Poisson's equation, the decohesion initiation problem is formulated in the form of a variational inequality. The asymptotic model assumes that the contact zone and its boundary contour during the detachment process are unknown. The absence of the solvability theorem is illustrated by an example of the instability of an axisymmetric flat circular contact., (© The Author(s) 2024.)

The phenomenon of rate-dependent adhesion has long been recognized as an intricate problem, and the so-far-developed physics and mechanics-based approaches resulted in analytical relations between the implicit form between the work of adhesion and the contact front velocity which are difficult to implement in practice. To address this issue in the framework of spherical indentation, the adhesion relaxation test in a nominal point contact is introduced to estimate the rate-dependent adhesion. Based on a stretched exponent approximation for the contact radius evolution with time, a relatively simple four-parameter model is proposed for the functional relation between the work of adhesion and the contact front velocity, and its fitting performance is compared to that of the known Greenwood-Johnson and Persson-Brener models.

The quasi-static regime of friction between a rigid steel indenter and a soft elastomer with high adhesion is studied experimentally. An analysis of the formally calculated dependencies of a friction coefficient on an external load (normal force) shows that the friction coefficient monotonically decreases with an increase in the load, following a power law relationship. Over the entire range of contact loads, a friction mode is realized in which constant shear stresses are maintained in the tangential contact, which corresponds to the "adhesive" friction mode. In this mode, Amonton's law is inapplicable, and the friction coefficient loses its original meaning. Some classical works, which show the existence of a transition between "adhesive" and "normal" friction, were analyzed. It is shown that, in fact, there is no such transition. A computer simulation of the indentation process was carried out within the framework of the boundary element method, which confirmed the experimental results.

There are cases of skeletal developmental features that have high identification significance for the search of missing person in forensic medical practice of skeletal remains examination. The features of the skull's anatomical structure may indicate the presence of some clinical syndromes, for which a person could have sought medical attention in the lifetime. In the described case, elongated styloid appendages of the temporal bones were identified on the skull of an unknown person found within the territory of the Leningrad region, which could be a sign of the stylohyoid syndrome (Eagle syndrome). Various clinical picture could be observed depending on the size and degree of styloid processes. The objective of the forensic medical expert was to establish the probability of occurrence of the stylohyoid syndrome and its possible clinical signs.

In reported experiments, a steel indenter was pressed into a soft elastomer layer under varying inclination angles and subsequently was detached under various inclination angles too. The processes of indentation and detachment were recorded with a video camera, and the time dependences of the normal and tangential components of the contact force and the contact area, as well as the average contact pressure and average tangential stresses, were measured as functions of the inclination angle. Based on experimental results, a simple theoretical model of the indentation process is proposed, in which tangential and normal contacts are considered independently. Both experimental and theoretical results show that at small indentation angles (when the direction of motion is close to tangential), a mode with elastomer slippage relative to the indenter is observed, which leads to complex dynamic processes-the rearrangement of the contact boundary and the propagation of elastic waves (similar to Schallamach waves). If the angle is close to the normal angle, there is no slipping in the contact plane during the entire indentation (detachment) phase.

Thermal stability is an important feature of the materials used as components and parts of sensors and other devices of nanoelectronics. Here we report the results of the computational study of the thermal stability of the triple layered Au@Pt@Au core-shell nanoparticles, which are promising materials for H 2 O 2 bi-directional sensing. A distinct feature of the considered sample is the raspberry-like shape, due to the presence of Au nanoprotuberances on its surface. The thermal stability and melting of the samples were studied within classical molecular dynamics simulations. Interatomic forces were computed within the embedded atom method. To investigate the thermal properties of Au@Pt@Au nanoparticles, structural parameters such as Lindemann indexes, radial distribution functions, linear distributions of concentration, and atomistic configurations were calculated. As the performed simulations showed, the raspberry-like structure of the nanoparticle was preserved up to approximately 600 K, while the general core-shell structure was maintained up to approximately 900 K. At higher temperatures, the destruction of the initial fcc crystal structure and core-shell composition was observed for both considered samples. As Au@Pt@Au nanoparticles demonstrated high sensing performance due to their unique structure, the obtained results may be useful for the further design and fabrication of the nanoelectronic devices that are required to work within a certain range of temperatures.

Aims: Dysregulation of pancreatic fat and lipotoxic inflammation are common clinical findings in alcoholic chronic pancreatitis (ACP). In this study, we investigated a relationship between dysregulated pancreatic lipid metabolism and the development of injury in a chronic ethanol (EtOH) feeding model of hepatic alcohol dehydrogenase 1- deficient (ADH - ) deer mice., Methods: ADH - and hepatic ADH normal (ADH + ) deer mice were fed a liquid diet containing 3 % EtOH for three months and received a single gavage of binge EtOH with/without fatty acid ethyl esters (FAEEs) one week before the euthanasia. Plasma and pancreatic tissue were analyzed for lipids including FAEEs, inflammatory markers and adipokines using GC-MS, bioassays/kits, and immunostaining, respectively. Pancreatic morphology and proteins involved in lipogenesis were determined by the H & E staining, electron microscopy and Western blot analysis., Key Findings: Chronic EtOH feeding in ADH - vs. ADH + deer mice resulted in a significant increase in the levels of pancreatic lipids including FAEEs, adipokines (leptin and resistin), fat infiltration with inflammatory cells and lipid droplet deposition along with the proteins involved in lipogenesis. The changes exacerbated by an administration of binge EtOH with/without FAEEs in the pancreas of ADH - vs. ADH + deer mice fed chronic EtOH suggest a metabolic basis for ACP., Significance: These findings suggest that the liver-pancreatic axis plays a crucial role in etiopathogenesis of ACP, as the increased body burden of EtOH due to hepatic ADH deficiency exacerbates pancreatic injury., 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 Elsevier Inc. All rights reserved.)

Osteoarthritis is one of the most severe diseases of the human musculoskeletal system, and therefore, for many years, special attention has been paid to the search for effective methods of its treatment. However, even the most modern methods only in a limited number of cases in the early or intermediate stages of osteoarthritis lead to positive treatment results. In the later stages of development, osteoarthritis is practically incurable and most often ends with disability or the need for joint replacement for a large number of people. One of the main reasons hindering the development of osteoarthritis treatment methods is the peculiarities of articular cartilage, in which there is practically no vascular network and tissue homeostasis is carried out mainly due to the diffusion of nutrients present in the synovial fluid. In modern medicine, for the treatment of osteoarthritis, tissue engineering strategies have been developed based on the implantation of scaffolds populated with chondrogenic cells into the area of the defect. In vitro studies have established that these cells are highly mechanosensitive and, under the influence of mechanical stimuli of a certain type and intensity, their ability to proliferate and chondrogenesis increases. This property can be used to improve the efficiency of regenerative rehabilitation technologies based on the synergistic combination of cellular technologies, tissue engineering strategies, and mechanical tissue stimulation. In this work, using a regenerative rehabilitation mathematical model of local articular cartilage defects, numerical experiments were performed, the results of which indicate that the micro-and macro environment of the restored tissue, which changes during mechanical stimulation, has a significant effect on the formation of the extracellular matrix, and, consequently, cartilage tissue generally. The results obtained can be used to plan strategies for mechanical stimulation, based on the analysis of the results of cell proliferation experimental assessment after each stimulation procedure in vivo ., 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 Popov, Poliakov and Pakhaliuk.)

Ilheus virus (ILHV) is a mosquito-borne flavivirus circulating throughout Central and South America and the Caribbean. It has been detected in several mosquito genera including Aedes and Culex , and birds are thought to be its primary amplifying and reservoir host. Here, we describe the genomic and morphologic characterization of ten ILHV strains. Our analyses revealed a high conservation of both the 5'- and 3'-untranslated regions but considerable divergence within the open reading frame. We also showed that ILHV displays a typical flavivirus structural and genomic organization. Our work lays the foundation for subsequent ILHV studies to better understand its transmission cycles, pathogenicity, and emergence potential.

The analysis of 387 cases of mandibular fractures complicated by posttraumatic infections is presented. These infections were quite diverse - from local suppuration of soft tissues surrounding the fracture to widespread processes affecting fatty tissue planes, including the anterior and posterior mediastinum. Infectious complications determine the injury outcome in each case - recovery, disability, or death. Two clinical observations with lethal outcomes are described.

Herein, we describe the design of a laboratory setup operating as a high-precision tribometer. The whole design procedure is presented, starting with a concept, followed by the creation of an exact 3D model and final assembly of all functional parts. The functional idea of the setup is based on a previously designed device that was used to perform more simple tasks. A series of experiments revealed certain disadvantages of the initial setup, for which pertinent solutions were found and implemented. Processing and correction of the data obtained from the device are demonstrated with an example involving backlash and signal drift errors. Correction of both linear and non-linear signal drift errors is considered. We also show that, depending on the research interests, the developed equipment can be further modified by alternating its peripheral parts without changing the main frame of the device.

Phenotypic signs of dominants isolated from the surface of bony remnants from the historic burial site were analyzed in order to expand data on the biodiversity of microorganisms in the microbial flora of bony remnants and to assess the possibility of using the results of microbiological analysis in the evidence base of forensic examination and forensic archaeology. It was detected that only Deuteromycota and Eubacteria colonized all types of surfaces in the samples of bone fragments from the historic burial site (with the age in the range of 90-95 years); with the abundance of micromycetes, the proportion of Eubacteria naturally decreased, while with the increased bacterial background counts the rate of micromycetes detection decreased. The insignificant amount of nutrients in the bony remnants led to the decrease in the number and biological diversity of microorganisms contaminating them; species adapted to a hard-to-reach organic substrate dominated there. During the process of bony remnants decomposition, when the conditions of their location changed, inter-species competition and specific recolonization occurred by species of microorganisms most adapted to a hard-to-reach organic substrate in the abiotic and biotic conditions of existence given. The results obtained are important for the descriptive ecology and biology of specific groups of microorganisms in the postmortem microbiome and form the basis for a more thorough study of complex communications between species of microorganisms in the necrobiome of bony remnants - in the future it will allow putting forward original hypotheses about the involvement of microbes in the circulation of matter and energy, as well as to apply the information obtained in the evidence base of forensic examination and forensic archaeology.

The Aim of the Study: Is to justify using the corpses of large mammals as model objects for studying the postmortem period. Similarities in processes occurring postmortem in human and swine corpses (decomposition stages and the structure of dominant necrophilic organisms inhabiting the corpse), as well as similar changes of relative impedance parameters for the cartilaginous tissue and musculoskeletal flap of swine and human corpses have been established. The results obtained allow recommending the swine corpse as an adequate human corpse model both for scientific studies and for solving specific scientific and practical issues arising in the practice of forensic examination when determining the prescription of death coming and the postmortem period conditions.

Studies of Russian and foreign literature have shown that the features of mechanical injuries and the course of diseases in different pediatric age categories remain insufficiently investigated in forensic pediatrics, taking into account their physiological characteristics and concomitant pathology. Based on this, it is proposed to develop the diagnostic criteria for both mechanical injuries and diseases of children as priority and promising areas in scientific research, taking into account the age-related physiological characteristics, as well as the effects of external factors on the course of the pathomorphological process; to create a single algorithm for a comprehensive pathomorphological analysis of pediatric pathology, which allows forensic experts to fully answer questions concerning the prescription of injuries, the pathogenesis of diseases, and determining the severity of the harm to the child's health.

The aim of the scientific work is to justify the need to highlight the topic of injuries after the biological exposure in forensic medicine. The definition of the «biological trauma» concept is presented - it means impairment of the body structure and function as a result of a special injury effects typical for wildlife representatives (animals, plants). Biological exposure includes antigenic, toxin, allergic, bioelectric, bioorganic exposures and their combinations. Biological injuries should be distinguished from mechanical injuries caused by small, medium, and large mammals and reptiles. Options of the antemortem and postmortem biological factor effects are considered. The qualitative limits of the postmortem period are defined. A new method of forensic reconstruction of postmortem conditions is proposed. Forensic entomological, forensic microbiological examinations, and their complex combination with forensic examination are isolated as independent methods.

Main directions of scientific and scientific-practical activity of the professor Mikhail Ivanovich Avdeev are described in the article. These include: a set of scientific tasks to justify the staff and organizational structure, organization and justification of the expert work content in the specialized military forensic service, including the training programs development for specialization and thematic improvement of forensic experts; determining the limits of competence for forensic experts in determining the violent death type; systematization of causes and death conditions; establishing structure of sudden death causes in young persons; assessment of the pathogenetic role of trauma and pathology in the development of basal subarachnoid hemorrhages; formulation of the conceptual base content for forensic medicine; justification of a scientifically based sequence of forensic medicine reproduction; creation of a scientific school of military forensic experts; preparation and publication of about 50 textbooks, manuals and, monographs on forensic medicine, including the fundamental work «Forensic Medicine Course», «Forensic Examination of Living People», «Forensic Corpse Examination».

The aim of the scientific work is to analyze the prospects of using the impedance monitoring method to determine the prescription of death coming. The conducted exploratory analysis allows hypothesizing the dependence of impedance values and dispersion factors for the diagnostic zones studies on the postmortem interval; it also suggests that it is possible to determine this interval for the objects (pig corpses) studies with a combination of impedance values and the corresponding factors. Among large mammals, a swine is the closest to a human from the point of analyzing the postmortem period process, and it can be recommended as an adequate human corpse model. When determining the correlation between the postmortem interval and the impedance parameters, it is the simplicity and reproducibility of the method, the absence of expensive equipment, its portability and the rapid receipt of results that allow this method to be applied at the scene, reinforcing traditional forensic methods for determining the prescription of death coming. Interpretation of impedance monitoring results can be used to analyze the biological nature of the postmortem period processes.

Pathomorphological changes in internal organs due to the toxic effects of the black mamba venom are nonspecific in nature and presume its neurotoxic and cardiotoxic effects with the development of the DIC syndrome, pulmonary edema, and brain edema in the terminal period. In forensic medicine, the development of specific diagnostic criteria, as well as an algorithm for detecting toxins of the black mamba venom in biological fluids and tissues of internal organs can become a promising topic for scientific research.

The purpose of the scientific work is to outline the main stages of the development of forensic examination of gunshot injuries in Russia. The analysis of the special literature from 1865 to the present time has demonstrated that the issue of forensic examination of gunshot injuries has been analyzed quite deeply by Russian forensic specialists. Meanwhile, expert practice sets forth tasks that are associated with the emergence of new firearm samples and new methods of laboratory and instrumental diagnosis.