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BACKGROUND:The operation of hydraulic drives of agricultural machinery is associated with the problem of leakage of fuel and lubricants, leading to contamination of water and soil. The most intense oil spill occurs when high-pressure hoses of hydraulic equipment are destroyed. The existing methods of solving the problem of oil leakage from high-pressure hoses have severe restrictions and high costs of their implementation. One of the effective methods of solving the problem is the use of hydraulic drive protection devices that disconnect the unpressurised section from the pressure source. AIMS:To develop an improved protection device an emergency stop device that controls a hydraulic drive with several types of hydraulic motors with a minimum number of device elements. MATERIALS AND METHODS:The design of a hydraulic drive emergency stop device (RUF Patent No. 2522013) installed in the hydraulic system of a tractor with single- and double-acting hydraulic cylinders has been developed. The method in use is a morphological analysis of the structure and distinctive features of existing engineering solutions. RESULTS:The shutdown unit and the terminal sensor of the emergency stop device compare the value of the hydraulic pump supply with the flow rate in the drain line. At the same time, the device is able to automatically adjust itself to their permissible difference, ensuring that there are no false responses when using double-cavity hydraulic cylinders with one rod. False responses when connecting a single-cavity hydraulic cylinder are prevented by using an additional flow sensor that blocks the shutdown unit. The fluid flow is throttled in the annular gaps between the pistons, sensor and shutdown unit housings; in this case, both pistons are mutually balanced. CONCLUSIONS:The proposed solution is aimed to eliminate significant oil throw-out form high-pressure hoses and makes it possible to use a single device for controlling the whole tractor hydraulic system. As a result, the weight and cost of the protection device reduce and the hydraulic drive scheme does not complicate significantly. The developed device does not demand additional power supply from the tractors on-board power circuit, as it operates with use of hydraulic energy. The protection device is applicable to hydraulic cylinders and hydraulic motors of various sizes thanks to ability of self-adjustment to the greatest difference in flow rate.

The condition for high precision machining of parts on CNC machines is that the actual movements of the cutting tool correspond to the information recorded in the control program. In real production conditions, processing errors often occur, the magnitude of which depends on many factors that are difficult to predict. The occurrence of errors is significantly affected by the technical condition and quality of adjustment of the technological system of the machine, temperature deformations, elastic deformations of the elements of the machine, devices and workpieces from the action of cutting forces. The task of forecasting the amount of elastic deformations and taking into account the data at the stage of preparing the control program is relevant and provides an opportunity to increase the accuracy of processing. To create a mathematical model of the formation of the processing error due to the action of elastic deformations of a specific machine, it is necessary to have data on the magnitude and direction of displacement in the space of the elements of the technological system due to the action of cutting forces. The range of efforts and the direction of action must correspond to the conditions of possible processing on a machine of a certain model. The necessary data can be obtained with the help of a device for simulating cutting forces in different places of the working area. According to the results of the research, the values ​​of elastic deformations of the machine elements in different coordinates of the working area are measured. A database is formed for each machine, which reflects the technical condition and rigidity of the elements of the technological system. For ease of recording and further use, a model is built using spline functions based on research data. The using of the results by elastic deformations simulation on CNC machines is advisable at the stage of preparation of the processing control program. When calculating the trajectory of the movement of the forming tool, it is possible to make corrections to compensate for the expected errors due to the action of elastic deformations. A significant effect from the implementation of this approach is possible in cases of processing surfaces of complex shape with high accuracy.

Abstract Monounit and modular switches of high-power current pulses with an operating voltage of 12 kV, made on the basis of series-connected shock ionized dynistors, are described. The switching processes of these switches are studied. The dependence of switching energy losses on the control pulse power is determined. The possibility of switching nanosecond current pulses with an amplitude of several kiloamperes at a frequency of several hundred hertz is shown.

Clinical case of structural epilepsy in a patient with multiple sclerosis is presented, which shows the achievement of seizure’s stable remission, which is extremely rare in forms of epilepsy with a multi-focal lesion another etiology and a long history of the disease without combination with multiple sclerosis. Video-EEG monitoring, positron emission tomography of the brain with 18F-deoxyglucose, expand the possibilities of diagnosing form of epilepsy in patients with combined pathology, which allows prescribing adequate therapy.

A clinical case of a patient with pharmacoresistant epilepsy due to focal cortical dysplasia (PCD) directly adjacent to the speech zone in the left temporal region is presented. The diagnostic search and transition from MRI-negative form to structural focal epilepsy progressed for more than 6 years. It was accounted for by the fact that type IIa vs. IIb FCD is visualized much worse, magnetic resonance imaging (MRI) signs of type IIa FCD are not so prominent, so that this type of dysplasia is often omitted. Functional research methods in epileptology, such as video-electroencephalography monitoring, brain positron emission tomography with 18F-fluorodeoxyglucose, functional MRI of speech zones, allow to more accurately verify the form of epilepsy and determine a scope of surgical treatment. Surgical intervention in carefully selected patients may contribute to favorable outcome of epilepsy (Engel 1, 51-months follow-up), which will lead to improved quality of life.

The article presents a clinical case of perineal defect reconstruction using a VRAM flap in a patient with vulvar cancer. Stepwise surgical treatment method is described. A multidisciplinary meeting allows to realize a plan of surgical help for such patients with the goal of treating oncological process and its complications.We have proposed a variant of perineal defect reconstruction through transfer of a vertical rectus abdominis musculocutaneous flap with a vascular pedicle.

Bulk metallic glasses (BMG) are promising materials due to their mechanical properties. The main difficulty in obtaining products from BMG is the massive parts, since a high cooling rate is required to preserve amorphous state. The use of additive manufacturing will avoid the need to obtain massive billets by conventional methods. In addition, using selective laser melting (SLM) technology, the material is selectively fused and the cooling rate is sufficient to avoid crystallization in the material. However, despite the high cooling rates, crystal formation is possible in some processing modes. In order to avoid crystallization, it is necessary to better understand the processes occurring in the laser-processing zone. In this work, we visualize laser processing of metallic glass plates by a high-speed camera to estimate the size of the melt pool. The melting front of the melt pool is clearly observed, while it is not possible to identify the crystallization front on the video frames. Additional image processing helps to visualize the melt pool. Using a photo editor, adjacent frames are subtracted, which make it possible to determine the boundary of the melt pool by comparing frames. Using this method, we are able to estimate the location of the crystallization front, which allows us to estimate the size of the melt pool.

The authors analyzed the state of tool production in Russia. The main manufacturing companies and the main brands of materials used in the production of domestic tools are highlighted. Powder high-speed steels are practically not used in the domestic market, but they are widely distributed in the foreign market of tool steels due to their significant advantages in terms of basic and technological properties (including the possibility of using high-carbon and high-alloy high-speed steels). There is a new group of economically alloyed tungsten-free high-speed steels with a high content of carbon and vanadium, which are practically impossible to manufacture and apply in our traditional technology due to low technological properties. The authors give recommendations on the technology of manufacturing such steels by powder metallurgy and on the modes of their heat treatment. The paper studies a set of properties of these steels, including: basic mechanical properties (hardness, bending strength, toughness, and heat resistance), basic technological properties (pressure, cutting, grinding) and operational properties (evaluated by tool durability during turning). Structural and phase compositions of the steels and their influence on the basic and technological properties were investigated. The compaction mode affects the density of the billets. The paper presents distribution of alloying elements in the microstructure of powder high-speed steel and results of their relative grindability. Also the durability of tools was tested. There are significant advantages of high-carbon high-vanadium high-speed steels, especially in terms of technological properties, compared with traditional high-speed steels. It is possible to produce high-alloy tool steels using inexpensive carbide-forming alloying elements. The steels under consideration can be used to manufacture a wide range of tools, including hot-forming die tools. The use of powder technology opens up the prospect of developing universal economically alloyed powder tool steels.

A technique for evaluating the efficiency of using ultra-wideband pulses (UWB) for signal transmission by digital modems in a closed space is proposed. The studies were carried out for the variant of approximation of the ultra-wideband signal by the Gaussian function. Approximation by a Gaussian monocycle is adopted for the radiated electromagnetic signal. Analytical expressions are given for calculating the width of the spectrum of the signal under study. Taking into account the obtained spectral characteristics, the calculation of the signal energy as a whole and in the given frequency bands was carried out. A comparative quantitative assessment of the energy efficiency of an ultra-wideband signal and a short radio pulse has been carried out.

The operation of applying riffles by local plastic forming on the inner surface of a cylindrical shell with the help of a working mandrel with wedge protrusions on the working surface is considered. The results of computer simulation are presented, and a comparison is made with the known reduction corrugation method. A significant decrease in the technological force in the process of corrugation and removal of a cylindrical shell using a new method has been established

The principle of vibroacoustic systems operation for determining the distance of a ski jump from a springboard, the possible location of sensors on the springboard and sensor signals that occur when athlete lands are considered. The problems of calculating the jump distance and methods for solving these problems are described. The interrelation of the technique of performing a jump (the spatial position of the skis at the time of landing and the normal component of the landing speed relative to the surface of the springboard) with the form of sensor signals is considered. Real waveforms of signals obtained both during the summer artificial covering of the springboard and in winter, as well as generalized results of experimental operation of the system on springboards with different heights of the acceleration mountain are presented. It is shown that the use of vibroacoustic systems allows achieving the required accuracy of determining the ski jump distance – 0.5 m, and the integration of the system with the general jump monitoring system opens up new opportunities for independent training of athletes and training of a group of athletes under the guidance of a coach.

Introduction. The regional geographic information system, being a tool for information and analytical support for making managerial decisions, has been widely used in almost all areas of the Federal Service in the field of consumer protection and human well-being, increasing their effectiveness and efficiency. Purpose. To analyze the effectiveness of the use of a regional geographic information system in solving the problems of the sanitary and epidemiological well-being of the region and to assess the prospects for the development of this system in the activities of the service. Material and methods. Retrospective analysis of the results of the adopted management decisions to improve the state of the environment and health of the population based on the implemented regional geographic information system. Results. The conducted retrospective analysis showed the high efficiency of using regional geoinformation systems when performing environmental and hygienic studies to assess the state of public health, environmental pollution, and in particular, to establish cause-and-effect relationships between the influence of environmental factors on public health and medical demographic indicators. Limitations. The limitation of the study is due to the inability to analyze the long-term experience of using geoinformation systems in solving the problems of sanitary and epidemiological well-being, as well as the lack of indicators of the effectiveness of their use on examples from other regions. Conclusion. The use of geoinformation technologies makes it possible for the authorities of the region to visually present information on priority hygienic and epidemiological problems in a particular administrative territory, and helps to determine the priorities for developing measures aimed at preserving the health of the population.

The article presents the results of improving the methodological foundations of managing the investment attractiveness of the region. A scheme of the structure of the management subsystem responsible for the investment attractiveness of the region has been developed. The external factors influencing the subsystem of management of the investment attractiveness of the region are determined. Criteria for optimizing investment attractiveness management processes at the regional level have been formed.

Abstract The results from studies of a high-voltage unit of shock-ionized dynistors in the switching mode of current pulses with an amplitude of several kiloamperes and a rise rate of up to 100 kA/μs are presented. The control circuit of this unit with a front sharpener of the trigger voltage pulses is described, which provides a significant reduction in energy losses in dynistors.

A new method for obtaining of responsible purposes products with applied corrugations on the inner surface of a cylindrical shell using the mandrelling method and local plastic change is presented. The technological process and the advantages of the new method are described. Schemes of the process and an example of its implementation are given.

The purpose of the article is to reveal the possibilities of information modeling of technological processes of effective infocommunication systems, which allows increasing the reliability and quality of systems. As a rule, service order flows are taken as poisson streams, which is true not in all cases, therefore, it is necessary to consider a modification of the Kolmogorov equation in order to obtain a system of equations that are valid for any variances, which will allow them to be used in any supply chains. It is shown that the information approach to modeling systems allows in real conditions to refine the algorithm or simplify and speed up the procedure of finding a solution by using the method of queuing chains. Both purely production (technological) processes and information processing processes in telecommunication and computing complexes can be connected with such chains. Consequently, the model developed will allow changing the conditions for setting the task of network modernization and finding the optimal solution. The prospects of the method are shown, since it is designed for the effective use of technical means in the construction of infocommunication systems.

This study determined the 3D structure of glutelin type-B 5-like (GTB) protein from proso millet using homology modeling and investigated the effects of simulated temperature and static electric field on its secondary structures, solvent accessibility surface area (SASA), the radius of gyration (Rg), root mean square deviation (RMSD), and total dipole moment. The result showed that the structure of GTB is majorly a protomer that comprises three monomers with one jelly-like β-barrel and two extended helix domains, and the remaining 35% as coils. Based on the molecular dynamic simulation, the secondary structure of the protein was not disrupted at temperatures between 300–400 K and static electric fields of between 0.1-3 V/nm, albeit the loss of a few amino acid residues. The RMSD increased significantly with an increase in temperature, static electric field, and simulation time. But the Rg and SASA decreased for the same conditions, suggesting that, the protein structure is compacting during thermal and electrical treatment.

In this study, we modified the multiple alignment method based on the generation of random position weight matrices (RPWMs) and used it to search for tandem repeats (TRs) in the Capsicum annuum genome. The application of the modified (m)RPWM method, which considers the correlation of adjusting nucleotides, resulted in the identification of 908,072 TR regions with repeat lengths from 2 to 200 bp in the C. annuum genome, where they occupied ~29%. The most common TRs were 2 and 3 bp long followed by those of 21, 4, and 15 bp. We performed clustering analysis of TRs with repeat lengths of 2 and 21 bp and created position-weight matrices (PWMs) for each group; these templates could be used to search for TRs of a given length in any nucleotide sequence. All detected TRs can be accessed through publicly available database (http://victoria.biengi.ac.ru/capsicum_tr/). Comparison of mRPWM with other TR search methods such as Tandem Repeat Finder, T-REKS, and XSTREAM indicated that mRPWM could detect significantly more TRs at similar false discovery rates, indicating its superior performance. The developed mRPWM method can be successfully applied to the identification of highly divergent TRs, which is important for functional analysis of genomes and evolutionary studies.

Measurement has a special role in quantum theory1: by collapsing the wavefunction it can enable phenomena such as teleportation2 and thereby alter the "arrow of time" that constrains unitary evolution. When integrated in many-body dynamics, measurements can lead to emergent patterns of quantum information in space-time3-10 that go beyond established paradigms for characterizing phases, either in or out of equilibrium11-13. On present-day NISQ processors14, the experimental realization of this physics is challenging due to noise, hardware limitations, and the stochastic nature of quantum measurement. Here we address each of these experimental challenges and investigate measurement-induced quantum information phases on up to 70 superconducting qubits. By leveraging the interchangeability of space and time, we use a duality mapping9,15-17 to avoid mid-circuit measurement and access different manifestations of the underlying phases—from entanglement scaling3,4 to measurement-induced teleportation18—in a unified way. We obtain finite-size signatures of a phase transition with a decoding protocol that correlates the experimental measurement record with classical simulation data. The phases display sharply different sensitivity to noise, which we exploit to turn an inherent hardware limitation into a useful diagnostic. Our work demonstrates an approach to realize measurement-induced physics at scales that are at the limits of current NISQ processors.

Currently, forest climatic projects aimed at enhancing the carbon sequestration in forest ecosystems are becoming very popular. The main requirements for such projects include additionality, permanence and the absence of leakage. Compliance with these requirements ensures that the project fulfils the tasks at which it is aimed. Predictive modelling can be one of the tools for checking the compliance of forest climate projects with the above principles. The purpose of the study was to assess the prospects for carbon accumulation during the implementation of reforestation projects in the Krasnoyarsk and Irkutsk regions. An assessment of the carbon balance in the territory of artificial reforestation projects was carried out at the baseline (natural regeneration of Betula spp. and Populus tremula L.) and during the implementation of the forest climatic project (planting of Pinus sylvestris L.) with a forecast for 100 years. The results show that during the implementation of the project, the achieved level of emissions is higher and the level of carbon sequestration is lower compared to the baseline, which contradicts the principle of additionality, and, therefore, artificial reforestation cannot be considered as a forest climatic project. The highest efficiency in carbon sequestration for mixed plantations is predicted for mixtures of Pinus sylvestris with 20–30 percent of small-leaved species (Betula spp. and Populus tremula). However, the implementation of artificial reforestation projects can be essential for the reproduction of valuable forest resources, but in this case it is necessary to take into account the way the obtained phytomass of trees is used, since the length of the carbon conservation period will depend on this.

We have developed a new interpretation of the Povarnitsa High, located in the southern part of the transition zone between the Chernyshov swell and the Kosyu-Rogov trough in the Polar Urals foreland. Petroleum exploration in this area took place in the 1980s and resulted only in an uneconomical oil deposit. Reprocessing and reinterpretation of vintage data and a newly acquired 3D seismic survey along with nonseismic geophysical data provided new insight into the geologic setting of the area. It found a subthrust extension of the Povarnitsa High, overlain by a backthrust sheet floored by upper Ordovician evaporites. This backthrust sheet interpretably resulted from the squeezing of the salt diapir during the late Permian contraction. Stratal patterns of the Silurian-Carboniferous section adjacent to the salt structures suggest early precontraction initiation of the halokinetic deformation, which influenced the distribution of reservoirs such as reefs and oolites. We consider the salt-cored subthrust structural culmination a principal hydrocarbon prospect. It includes multiple reservoir-seal pairs in the Silurian-Permian section at depths ranging from 1 to 4 km. The updated structural model of the Povarnitsa High area suggests that the vintage wells penetrated prospective intervals at the periphery of the closure approximately 1 km downdip from the subthrust crest of the prospect.

The study presents two clinical observations of delayed reconstructive surgeries: 1) in a patient with recto-bladder fistula formed after a course of external beam therapy due to recurrent prostate cancer; 2) in a patient with progressing cervical carcinosarcoma, tumor invasion in the bladder wall, and metastases in the rectoperineal lymph nodes. Absence of standards of care, algorithms of diagnostic and surgical manipulations for this patient category creates a need for personalized approach to the stated problems. An interdisciplinary meeting allows to realize a plan of surgical help for these patients to address oncological process and complications of its treatment. At the reconstructive stage, we used techniques of formation of a new continent heterotopic reservoir from the ileocecal segment and coloanal anastomosis. The presented clinical observations are interesting due to delayed stage of reconstructive interventions which in the absence of progression of the main disease allows to perform correcting operations to improve patients’ quality of life.

Aim. To analyze various strategies aimed at mitigating complications of the portal hypertension syndrome at the Minsk Scientific and Practical Center for Surgery, Transplantology, and Hematology.Material and methods. Patients who had undergone different types of treatment were retrospectively observed: shunt surgery to form portacaval anastomoses, transjugular portosystemic shunt placement, and liver transplantation. The following parameters were analyzed: incidence of complications, hospital mortality rate, survival rate, and perioperative indicators.Results. Since 1980, 131 shunt surgeries have been performed at the Center, while 880 liver transplantations and 232 transjugular portosystemic shunt placement procedures have been performed since 2008. Among 68 patients with compensated cirrhosis who had undergone shunt placement, no hospital mortality rate was reported, whereas in patients with Child-Pugh B cirrhosis and Child–Pugh C cirrhosis, it reached 19.5% and 87.5%, respectively. Following TIPS, the overall case mortality rate amounted to 9.9% (following TIPS prior to transplantation – 8.2%, following TIPS used as the final treatment – 12.8%). After liver transplantation, in-hospital mortality rate reached 7.7%.Conclusion. Over 50 years, the strategy for managing portal hypertension has undergone significant changes due to the establishment of institutions providing a complete cycle of all treatment measures for such patients. Patients suffering from the complications of the portal hypertension syndrome tend to receive the most effective treatment in hospitals having experience in rational conservative therapy, endovascular procedures, and transplantation.

The oxidation of methionine has emerged as an important post-translational modification of proteins. A number of studies have suggested that the oxidation of methionines in select proteins can have diverse impacts on cell physiology, ranging from detrimental effects on protein stability to functional roles in cell signaling. Despite its importance, the large-scale investigation of methionine oxidation in a complex matrix, such as the cellular proteome, has been hampered by technical limitations. We report a methodology, methionine oxidation by blocking (MobB), that allows for accurate and precise quantification of low levels of methionine oxidation typically observed in vivo. To demonstrate the utility of this methodology, we analyzed the brain tissues of young (6 m.o.) and old (20 m.o.) mice and identified over 280 novel sites for in vivo methionine oxidation. We further demonstrated that oxidation stoichiometries for specific methionine residues are highly consistent between individual animals and methionine sulfoxides are enriched in clusters of functionally related gene products including membrane and extracellular proteins. However, we did not detect significant changes in methionine oxidation in brains of old mice. Our results suggest that under normal conditions, methionine oxidation may be a biologically regulated process rather than a result of stochastic chemical damage.