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Aim. To reveal the peculiarities of structural reorganization of the endometrium in various variants of pregravid preparation in women with chronic endometritis (CE) and infertility. Materials and methods. We examined 90 women aged 1840 who were treated for CE. For all patients, examination with microbiological (cultural) examination of the cervical canal to be separated for aerobic and facultative anaerobic microorganisms with the determination of sensitivity to antibiotics, ultrasound examination (ultrasound) of the pelvic organs and morphological examination of endometrial biopsy samples before and after treatment. All women of the study group were divided into 2 subgroups. Patients of the 1st subgroup (n=30) received standard treatment for CE antibacterial and non-steroidal anti-inflammatory drugs; in the 2nd (n=60) an additional course of immunostimulating therapy with a bacterial lipopolysaccharide preparation was prescribed. Results. According to the cultural method, repeated cultures from the cervical canal after treatment turned out to be sterile more often in women of the 2nd subgroup. Ultrasound diffuse-focal changes in the subendometrial zone of the myometrium occurred in all patients before and after treatment. In the 2nd subgroup, after treatment, significant changes in the endometrium were noted in the form of an increase in its thickness and a 4-fold decrease in the number of hyperechoic inclusions in the basal layer, as well as the disappearance of the irregularity of the endometrial closure line. In the endometrial biopsies of women of the 2nd subgroup, a significant decrease in the specific area of the inflammatory infiltrate, the absence of foci of fibrosis, and an increase in the thickness of the vessel wall were noted. Conclusion. The addition of a bacterial lipopolysaccharide to the standard CE treatment regimen not only improves the microbiological environment of the female genital tract, but also significantly affects the morphofunctional state of the endometrium.

Vibrating devices occupy a large cluster in the construction and road construction industry. The improvement of all vibration machines begins, first of all, with a vibration device, as the main working body of the machine. Basically, vibrators acted as a vibrating device for all road construction equipment. Initially, vibrators with circular vibrations were used, which are not so effective and not always sufficient for performing special work on driving piles into the ground and also extracting them from the soil. Vibratory systems with asymmetric vibrations are increasingly being used in the construction industry. For example, when driving piles, pile drivers are used. Their principle of operation is similar in its action to the operation of a vibration plant with asymmetric vibrations. However, a vibration plant with asymmetric oscillations, when the direction of the driving force is turned in the opposite direction, not down, but up, also makes it possible to extract worn-out piles and sheet piles from the soil. Based on the above, we propose a description, a method for calculating the optimal values of the asymmetry coefficient, driving force and set out the principle of operation of a physical model of a vibration plant with two stages of generating asymmetric vibrations, consisting of standard vibration equipment: the first stage: a table of the brand EV-341 and the second stage : vibrator of directional vibrations brand IV-99B, manufactured by OOO Yaroslavl Plant Krasny Mayak.

The development of additive manufacturing leads to the emergence of new 3D printing technologies, new materials for 3D printing and a gradual reduction in the cost of production. Nowadays, the cost of equipment used for metal and metal powders 3D printing are still very expensive. This factor makes the production technologies unavailable for the civil engineering industry in the manufacture of functional parts. The cost of additive manufacturing of metal parts is mainly dependent on the volume of printing. Reducing the print volume can lead to a significant reduction in the cost of manufacturing the part. Fabrication of a metal shell, the cavity of which is filled with a cheap metal polymer, can be an excellent alternative to an all-metal part. Such a metal-metal-polymer composite part can have sufficient strength and significantly lower cost. However, there are no dependencies today to understand the economic efficiency of using a particular production technology. The article provides a method for calculating the cost of manufacturing a lever part using various technologies: subtractive, additive and composite part manufacturing technology. According to the calculated data, the dependence of the cost of manufacturing a part on piece time is built. It can be interpreted as the amount of machining. The constructed linear dependence can give an idea of the effectiveness of the application of a particular technology for obtaining a part. In addition, non-economic factors affecting the possibility of using various technological processes for manufacturing a part are described. Together, the presented data allow the technologist to comprehensively assess the possibility of effective application of a particular production technology and make an appropriate informed decision.

The article deals with the issue of evaluating the performance of a composite metal-metal-polymer mold. The use of a composite mold, including a forming plate consisting of a metal, and a metal polymer introduced with a low cooling efficiency of such a mold. For this reason, it is important to develop technological solutions that ensure the efficient operation of the cooling system. The article provides mathematical calculations of the required amount of heat flow when molding thermoplastics into a mold. Further, based on the calculated data, a study is made using finite elements of the thermal conductivity of the metal-polymer part. The design of the composite forming plate of the mold described in the article involves the manufacture of a cooling channel profile as close as possible to the forming part of the mold and located in the metal-polymer part. Based on the analysis of the temperature viscosity of the metal-polymer part of the mold, conclusions and recommendations are given for the design of a curved investment mold. It allows designers to calculate the optimal geometric parameters of the cooling system. The design and manufacture of conformal cooling stages in the metal-polymer part is likely to be preferable for cooling the forming part of the mold by bringing the cooling reversal surface closer to the surface of the forming mold, resulting in increased durability and productivity of the composite mold.

In 63 patients with suppurative bone process the activity of N-acetyl-fi-D-glucosaminidaze lysosomal enzyme in urine as well as oxyproline and hexuronic acids excretion were evaluated. Significant changes in metabolism of collagen and proteoglycans of osseous organic matrix were detected and it was confirmed by high excretion of their structural components. The more active and vaster the suppurative process was the more quantitative excretion of collagen and glu- cosaminoglycans and higher enzyme activity were. The suggestion was formulated that high excretion of N-acetyl-fl-D-glucosaminidaze in urine noted in the patients with suppurative inflammatory complications was the indicator of pathologic changes in tubular apparatus of kidney. The detection of excretion of the connective tissue metabolites (oxyproline and hexuronic acids) could be used for the diagnostic and prognostic evaluation of the disease severity and for the choice of method for the treatment of suppurative process.

The article deals with the issue of manufacturing conformal cooling channels to ensure efficient cooling of composite metal-metalpolymer molds. A brief description of both the design of the composite mold and the technology for its production is given. Conformal cooling channels in the composite mold are made in the metal-polymer part, which reduces the distance from the surface of the cooling channel to the cooled forming surface. Experimental studies are given on the example of a composite mold for the "collar" part. Fixing the temperature data of heating and cooling of the metal-polymer molding is carried out using a thermal imager. Evaluation of the results of the study show the efficiency of manufacturing conformal cooling channels directly in the metal-polymer part of the mold. An analysis of the experimental results allows numerically evaluating the cooling efficiency and comparing it with the cooling of a composite mold, in which the cooling channels are made in a metal cage. An assessment of the efficiency of using a composite mold with cooling channels made in the metal-polymer part in the context of saving the main technological time for the production of a batch of parts is given. In conclusion, the difficulties that arose in the process of manufacturing conformal cooling channels in the metal-polymer part and the tasks that require further research in the technology of manufacturing composite molds are described.

This study describes the internal structure of materials used to produce medical stents. A two-level elastoviscoplastic mathematical model, which sets the parameters and describes the processes at the grain level, was developed and numerically implemented. A separate study was conducted to identify the most dangerous deformation modes in the balloon-expandable stent placement using the finite-element method in COMSOL Multiphysics. As a result, the challenging strain state type required for setting the kinematic loading on a representative macrovolume in the two-level model was obtained. A yield surface for different deformation paths in the principal deformation space for stainless steel AISI 316L was obtained and the effect of grain size on the deformation behavior of this material was explored using the developed model.

The purpose of the article is to analyze the main results of the works that are used in the calculations of elevators with moderate speed modes, to clarify the suitability of their individual positions for developing the parameters of centrifugal unloading of high-speed elevators. Works devoted to the study of the operation of high-speed elevators, the results of which have not received a decent interpretation and development, are of considerable interest. As the efficiency of high-speed elevators is determined by the quality of centrifugal unloading and by the operation of the belt-drum mechanism without slipping, there is a need to analyze the work aimed at solving this problem. The paper presents known solutions for determining the parameters of centrifugal unloading, which are based on various hypotheses of the movement of material particles inside the bucket. The physical and mechanical phenomena that affect the movement of material particles in the elevator bucket are studied. The advantages and disadvantages of each hypothesis are revealed. The theoretical study of the process of centrifugal unloading is complicated by the fact that during the movement and exit of the material from the bucket, there is an unstable movement of the bulk material under the influence of a changing system of forces: the forces of attraction, centrifugal and coriolis forces, and the friction force. Meanwhile, even the simplest cases of material motion under a gravitational or mixed discharge regime are difficult to analyze theoretically. In this regard, the dependencies and methods of constructing the trajectories of the material movement are established, as well as the relevance of using a particular equation.

Vibrating machines play a primary role in the implementation of programs in the construction and road construction kit. The improvement of vibration machines allows to significantly increase the speed of construction and road construction work. The main working unit of a vibrating machine is a vibrating device or vibrator. Currently, in the industry, vibration devices are used with circular or directional, along a certain straight line of vibrations. Further improvement of vibrating machines is carried out in the direction of creating vibration devices with asymmetric vibrations. At present, there are practically no vibrating machines with asymmetric vibrations. These machines allow to distinguish between the "working" process phase and the "idle" phase within each oscillation period. Moreover, the value of the driving force in the phase of performing useful work is several times higher than the value of the driving force in the direction of idling. Therefore, much less work is spent on idling. This allows to get rid of massive elements - overloads that extinguish the magnitude of the driving force in the direction of idling. Therefore, the urgency is to develop a method for converting existing machines with directional vibrations into asymmetric ones, with a given coefficient of asymmetry of the driving force. This makes it possible to reduce the specific indicators of the metal consumption of vibrating machines and the energy consumption of the work performed.

Hydrothermal drying of low-grade coals was first suggested in Austria as early as in 1920, when it envisaged treatment of a lump coal with 180–240 °C steam in an autoclave. Hydrothermal treatment (HTT) of brown high-ash coals at 200 to 250 °C causes certain changes in their structure and physicochemical properties, similar to those under low-temperature pyrolysis. Moreover, these changes occur at values 50–100 °C below the pyrolysis temperatures, and the HTT product is close to semi-coke in terms of its calorific value. During hydrothermal treatment, the surface of the coal phase becomes more hydrophobic, while the specific surface of the mineral fraction decreases and the swellability is lost, which leads to lower adsorption activity. Taken in combination, these effects significantly modify the processing properties of coal. When only brown coal-water separation is required, the HTT may be performed without adding free water; when changes the processing properties of coals are necessary, it is advisable to carry out hydrothermal treatment in suspensions containing approximately 50 % of free water. This treatment not only causes the removal of moisture, but also leads to certain other changes in the coal structure. The study was supported by a grant from the Russian Science Foundation (project No. 18-17-00169).

A series of 73 ligands and 73 of their Cu+2 and Cu+1 copper complexes with different geometries, oxidation states of the metal, and redox activities were synthesized and characterized. The aim of the study was to establish the structure-activity relationship within a series of analogues with different substituents at the N(3) position, which govern the redox potentials of the Cu+2/Cu+1 redox couples, ROS generation ability, and intracellular accumulation. Possible cytotoxicity mechanisms, such as DNA damage, DNA intercalation, telomerase inhibition, and apoptosis induction, have been investigated. ROS formation in MCF-7 cells and three-dimensional (3D) spheroids was proven using the Pt-nanoelectrode. Drug accumulation and ROS formation at 40-60 μm spheroid depths were found to be the key factors for the drug efficacy in the 3D tumor model, governed by the Cu+2/Cu+1 redox potential. A nontoxic in vivo single-dose evaluation for two binuclear mixed-valence Cu+1/Cu+2 redox-active coordination compounds, 72k and 61k, was conducted.

The growing impact of assisted reproductive technologies on the quality of human life and health has required the leading countries to establish a legal framework in the sphere of biomedical research. The question of the legitimacy of genetic modification of human embryos for reproductive purposes is particularly acute. The public and the scientific community give a controversial ethical assessment of the prospects for human DNA editing to new generations. This fact arouses interest in the legal environment of countries that have achieved some success in the sphere of medical innovation. The People's Republic of China was one of the first countries to declare successful genetic research with human embryos. The purpose of this work is to identify the legal boundaries of research to create inherited modifications of the human embryo genome in China. The methodology used in the research: dialectical method as a universal tool of cognition with method of dogmatic (formal-legal) analysis, discourse analysis and case study. By using these methods managed to structure and meaningfully disclose the regulatory framework of the PRC, regulating genetic research of the human embryo for reproductive purposes. The legal documents regulating preclinical and clinical embryo genome studies are summarized. The particular attention is paid to legal precedent of human DNA editing.

Vibration machines make up a large class of construction and road construction equipment. The improvement of vibration machines is carried out in the direction of improving the vibration device as the main working body of the machine. For a long time, vibrators with circular vibrations are used as vibration devices, the effectiveness of which is not always sufficient when performing special work on immersing piles into and removing them from the soil. The priority area of development and creation of vibration devices for technological processes in the coming years is mechanisms with asymmetric oscillations. Vibration devices with asymmetric oscillations can significantly increase the efficiency of using vibration machines due to the fact that the driving force aimed at performing useful work exceeds the magnitude of the driving force directed at idling several times. However, at present there is no method for determining and calculating the parameters of vibration devices with asymmetric oscillations instead of circular vibrators. The purpose of the article is to consider a method for designing vibrational devices with asymmetric oscillations, based on the method of expanding a given function of changing the value of the total driving force into a Fourier series, the terms of which are the values of the driving forces generated by each stage of a multi-stage vibration mechanism. The study is based on classical analytical and numerical methods. The results obtained allows to use the methodology for evaluating the design method of a vibration device with asymmetric vibrations at the design stage and to evaluate the effectiveness of the designed vibration device.

Neuraxial administration of long-acting opioid is the "gold standard" for the management of postoperative pain following cesarean delivery. Respiratory depression, however, remains a concerning complication.This retrospective single-center study of 4963 patients evaluated the frequency of respiratory depression after neuraxial morphine administration in a post-cesarean delivery population. The spinal dose of morphine varied from 100 to 450 µg intrathecally, and from 3 to 5 mg epidurally. The primary outcome was the initiation of a Rapid Response Team (RRT) event for respiratory failure due to neuraxial opioid in the 24 h following morphine administration. Secondary outcomes studied included oxygen desaturation events (SpOThere were no respiratory RRT events within the study period (95% confidence interval [CI] 0 to 7 per 10 000). There were no desaturation events recorded and no patients received supplemental oxygen therapy or naloxone (95% CI 0 to 7 per 10 000).Clinically significant respiratory depression is rare among patients receiving neuraxial morphine for post-cesarean delivery analgesia.

The mechanisms with asymmetric vibrations is the priority direction of development and creation of vibration devices for technological processes in the coming years. Mechanisms with asymmetric vibrations are constructively created on the basis of vibrators with directional vibrations in the form of steps, which differ from each other in the mass of unbalances, the radius of displacement of the center of mass from the axis of rotation and the frequency of rotation of the unbalanced shaft. The simplest device with asymmetric oscillations is a two-stage mechanism. Optimization of parameters of vibrators of each stage can be carried out according to the coefficient of dynamism of the oscillatory system. Rational parameters of the mechanism are consistent with the highest value of the coefficient of dynamism of the system. Currently, there is no method of design calculation for the translation of circular, elliptical and equally directed oscillations into asymmetric ones. The article presents the method of calculation associated with the translation of the parameters of vibration devices with circular, elliptical and equally directed vibrations into asymmetric ones with the highest coefficient of dynamism.

When coal is crushed, it fractures along the bedding planes and also along the boundaries with mineral inclusions. In the latter case, the mineral inclusions are released and separated from the coal. The release of the mineral inclusions may be precisely measured, but special instruments are required and these methods are of little utility. In the present work, the release of mineral inclusions is calculated by means of the Hancock–Luyken formula for coal from three Russian fields. Different crushing methods are employed. The dispersion coefficient N indicates similar results for hammer crushing of coal from different fields. The effect on the mineral inclusions is basically the same when different disintegration methods are used. However, little crushing is observed when using the KID-300 hybrid system and two-stage treatment in the DShch-60×100 jawbreaker and the DG-200×125 roller system.

This article deals with a study of radiation-induced leakages between n-regions of various types using test structures fabricated according to the 0.18-µm CMOS technology. It is shown that, depending on the radiation exposure dose, the leakages between the n+-regions and the n-well may exceed the leakages between the n+-regions by 3–9 times, which should be taken into consideration when developing radiation resistant VSHICs.

The study objective is to analyze the connection between the level ofantisperm antibodies and pregnancy outcomes in pairs who underwent in vitro fertilization procedure due to secondary infertility. Materials and methods . At the center for family planning and reproduction V.N. Gorodkov Ivanovo Scientific Research Institute for Maternity and Childhood, a prospective cohort study of 46 women with a history of recurrent miscarriage and secondary infertility developed in the last year which became an indication for use of assisted reproductive technologies was performed. A comparative analysis of spermograms and MAR test results prior to ART was performed. The group 1 included pairs with MAR test result >10 %, the group 2 — MAR test result

The influence of the dominant radiation effects in bulk CMOS IC and VLSI on their electrical parameters and characteristics is analyzed. The effects of scaling and electrical modes on device and parasitic n-MOS transistors on the radiation hardness parameters are considered. The methodology of radiation-hardening-by-design of system-on-chip (SoC) and SRAM was developed for the 250-90 nm bulk CMOS processes. Technical solutions are proposed that provide an increased level of total ionizing dose tolerance, failure tolerance, and the absence of the latch-up effect. The framework for high-performance radiation-hardened SoC and SRAM design, containing standard cell libraries and IP-blocks, has been created. Basic technical solutions are certified on special test chips and as part of developed VLSI.

The paper considers modelling the wire deposition process with vertically fed wire by several symmetrically acting heat sources. We proposed the mathematical model to describe the above process, considering surface tension force, Marangoni force, vapor pressure force, and heat loss on evaporation. To solve the mathematical model, we use the smoothed particle hydrodynamics method. We carried out a series of numerical experiments for modelling the melting process of vertically fed wire with two symmetrically acting heat sources with different power and direction of action of heat sources. We found that vertical wire feeding provides uniform heating with the absence of shaded areas and flexible control of heat input into the metal. On the other hand, the weld bead geometry characteristics significantly depend on the heat sources’ power and direction.

The paper discusses problems related to the description of metals and alloys internal structure. By classical molecular dynamics simulation, we developed and numerically implemented mathematical model to describe a microcracks and edge dislocations trapping of impurity atoms. The embedded atom model is used to construct the interatomic interaction potential. Based on the analysis of local strain and stress fields, estimates are made for the capture radius of impurity atoms by an microcracks and edge dislocations in Fe-C. Besides, the trapping forms regions near the microcracks and edge dislocations were clarified.

In this chapter, we review the contribution of space missions to the determination of the elemental and isotopic composition of Earth, Moon and the terrestrial planets, with special emphasis on currently planned and future missions. We show how these missions are going to significantly contribute to, or sometimes revolutionise, our understanding of planetary evolution, from formation to the possible emergence of life. We start with the Earth, which is a unique habitable body with actual life, and that is strongly related to its atmosphere. The new wave of missions to the Moon is then reviewed, which are going to study its formation history, the structure and dynamics of its tenuous exosphere and the interaction of the Moon’s surface and exosphere with the different sources of plasma and radiation of its environment, including the solar wind and the escaping Earth’s upper atmosphere. Missions to study the noble gas atmospheres of the terrestrial planets, Venus and Mars, are then examined. These missions are expected to trace the evolutionary paths of these two noble gas atmospheres, with a special emphasis on understanding the effect of atmospheric escape on the fate of water. Future missions to these planets will be key to help us establishing a comparative view of the evolution of climates and habitability at Earth, Venus and Mars, one of the most important and challenging open questions of planetary science. Finally, as the detection and characterisation of exoplanets is currently revolutionising the scope of planetary science, we review the missions aiming to characterise the internal structure and the atmospheres of these exoplanets.

For several years, strengthened state support measures domestic livestock has reached on many qualitative and quantitative indicators of the European level. First of all, we are talking about industrial poultry farming and pig breeding, as well as dairy and beef cattle breeding in terms of increasing the genetic potential. At the same time, the direction of dairy cattle breeding remains one of the most problematic. Annually, purchases of expensive animals experiencing stress during transportation are carried out, which leads to a decrease in the vital energy and functional-physiological reserves of the body. In this regard, many questions arise related to the need to preserve these functional reserves, which can be studied using non-invasive methods. One of such methods is cardiointervalometry of heart rate variability. The method allows to assess the physiological state of the organism of an animal, on which factors, both exogenous and endogenous, can act. The obtained indicators can be used in conducting practical and lecture classes at veterinary faculties of universities, as well as serve as material for further research and discoveries.

Safety considerations have always accompanied the development of new battery chemistries; this holds especially for the Li-ion battery with its highly reactive components. An overall assessment and decrease of risks of catastrophic failures such as during thermal runaway, requires an in-depth and quantitative understanding of the ongoing processes and their interaction. This can be provided by predictive mathematical models. Thus, we developed a thermal runaway model that focuses on rigorous modelling of thermodynamic properties and reactions of each component within a Li-ion battery. Moreover, the presented model considers vapour–liquid equilibria of a binary solvent mixture for the first time. Simulations show a fragile equilibrium between endothermic and exothermic reactions, such as LiPF$_{6}$ and LEDC decomposition, in the early phases of self-heating. Further, an autocatalytic cycle involving the production of HF and the SEI component Li$_{2}$CO$_{3}$ could be revealed. Additionally, the unpredictability of the thermal runaway could be directly correlated to availability of LEDC or contaminants such as water. Also, solvent boiling can have a significant influence on the self-heating phase of a Li-ion battery, due to its endothermic nature. Further analysis revealed that the rising pressure, stemming from gassing reactions, can suppress solvent boiling until the thermal runaway occurs.

The development and use of a set of highly automated agricultural machinery is necessary to ensure the effective involvement of agricultural land and the development of the land amelioration complex. The work analyzes the prospects for the development of the market of highly automated machinery and shows the barriers that obstruct the development of this market in Russia and in the world. The paper describes the steps to overcome these barriers. The authors substantiate the actuality of creating normative technical and legal bases, as well as the necessity of creating a center for testing agricultural and forestry tractors for compliance with the safety regulations. The paper explains international and Russian standards for safety requirements for products of the highly automated machinery. The paper presents the activities that need to be carried out in order to use highly automated agricultural machinery.

The paper describes the relevance of the creation of a supporting laboratory for testing compliance with the Organisation for Economic Co-operation and Development (OECD) Tractor Code for agricultural and forestry tractors in conditions of international integration. The paper provides the international requirements for tractor products according to the OECD Tractor Code regulations. A set of activities for the creation of a supporting laboratory is presented. The study lists which methodologies need to be developed for testing tractor units and assemblies. It shows the procedure for validating tests at the OECD. It is pointed out that the development and use of digital services is necessary to ensure a leap forward in the development of integration in the field of technical regulation.

The prospective diesel-electric tracked tractor shall have a modular design, integrating the power frame, auxiliary systems, and control system. The tractor will have the following basic modules: a track module comprising an electric motor, gearbox, brake system, electric motor power casing; a diesel generator module consisting of an internal combustion engine of the power corresponding to the tractor’s traction class and a power generator. The article substantiates the need for a diesel-electric tracked tractor with a high degree of automation and unmanned control capability, which will be in demand in modern Digital Agriculture. The stages of technological change in global agriculture are presented. The paper outlines the advantages of tracklaying system and electromechanical transmission; functional diagram and target indicators of some technical characteristics of a diesel-electric tracked tractor with the electromechanical transmission; capabilities and functions of information and control digital, intelligent systems that are to be implemented in a diesel-electric tracked tractor for digital agriculture production.

The dry beneficiation of coal samples at different metamorphic stages (lignite, coal, anthracite) is compared, before and after heat treatment. By thermal modification of the coal in the absence of air, the unit ash content (the ratio of the ash content to the heat of combustion) may be reduced by a factor of 1.3–1.6. In other words, the ash and slag formation on combustion may be reduced. Intense magnetic and electrostatic separation may be used for dry beneficiation of high-ash fine-grain coal. The removal of the mineral fraction by such methods is more effective after pyrolysis of coal stocks at different metamorphic stages.

This article considers the issues related to the correct description of the internal structure of grain boundaries in metals. We offered a mathematical model describing grain boundaries formation as a result of two-sided crystallization by applying molecular dynamics method with third-type boundary conditions for heat extraction (Newton-Richman law). In the construction of the interatomic potential, the embedded atom method (EAM) is used. The work offers an algorithm for generation of initial conditions for two adjacent grains with different crystal lattices orientation and melt between them. To detect defects and defective areas we use a central symmetry parameter. The system energy before and after the crystallization process is estimated.