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Aim of the study was to analyze the course of coronavirus pneumonia in patients with pneumomediastinum. Material and methods. The study included 139 patients, 71 of whom developed spontaneous pneumomediastinum against the background of coronavirus pneumonia. Laboratory, clinical and radiological data were analyzed and compared. Results. The relationship between the severity of viral pneumonia (3rd–4th degree of severity according to MSCT) and pneumomediastinum was revealed. It was found that spontaneous mediastinal emphysema in patients with COVID-19 signifcantly more often leads to the development of acute respiratory distress syndrome, multiple organ failure and can be a predictor of negative prognosis of the disease outcome. Conclusions. Pneumomediastinum in patients with viral pneumonia caused by a new coronavirus infection is a predictor of severe disease and poor prognosis. With an increase in spontaneous mediastinal emphysema without pneumothorax, it is recommended to perform mediastinotomy according to Razumovsky’s indications, and in case of clinically signifcant concomitant pneumothorax – drainage and revision of the mediastinum.

Background. On metal-cutting machines, in mechanical assembly production and everyday life, vices of various designs are widelyused, which, as a rule, have a constant structure and one kinematic chain from the engine (or manual drive) to the clamping elements –jaws. The vast majority of them are adapted for clamping cylindrical objects (parts) and objects with plane-parallel sides. At the same time,in mechanical assembly production, as well as during repair work, it often becomes necessary to clamp spherical, wedge-shaped, conical,and irregularly shaped objects.Objective. The purpose of the paper is to propose a morphological set of universal vices taking into account the achievements inthe theory of fractals and alternatives to new features of the state, type of execution and mobility of clamping elements, and to come upwith morphological formulae of vices.Methods. A morphological model of the vices is being developed, which takes into account the achievements of the fractal theoryand makes it possible to predict new technical solutions for universal vices at the level of inventions.Results. The morphological formulae of universal vices from the morphological set which contains alternatives of new signs of acondition, a type of execution and mobility of clamping elements, and also prerequisites for using the fractal theory for clamping processmodelling of complex shape details are offered.Conclusions. Using the proposed approach, it is possible to predict new technical solutions of universal vices at the level of inven-tions for the manufacture, research and subsequent commercialization

The creation of a highly effective model for diagnosing liver diseases of various genesis (including subclinical forms) in animals is one of the most urgent problems of veterinary science. Currently, there is a need to create more specific than "classical" tests for a clear differentiation of various pathologies of the hepatobiliary system, including diseases characterized by the absence of pathognomonic clinical or laboratory signs. One of the extremely promising predictors of such pathologies is bile acids (BA) and their pool. The main goal of the study is to search and analyze information from scientific publications dedicated to the study of the BA’s pool in various animal species, its changes in various pathologies of the hepatobiliary system and its diagnostic value. In English and Russian, in accordance with the recommendations of H. Snyder, various bibliographic databases (Elibrary, Pubmed, Scopus (Elsevier), Web of Science (Clarivat)) were searched for thematic publications by keywords with further highlighting the most cited ones. Articles published before 2015 were used only if they contained information critical to the better understanding of the topic, or it was not found in later publications. Based on the literature analysis, it can be concluded that liver diseases affect the synthesis and metabolism of bile acids. Therefore, BAs separately and their pool are studied and utilized as diagnostic and prognostic markers. However, it is not yet clear how the etiology of liver diseases affects the composition of bile acids. It should also be noted that in different animals there are differences in the BA pool, as well as in the details of their metabolism. This indicates differences in the specificity, affinity, and activity of enzymes involved in BA synthesis. Thus, BAs also affect the etiopathogenesis of diseases of the hepatobiliary system differently for each animal species, and, conversely, etiopathogenetic factors change the pool of BAs depending on the individual characteristics of the species.

The article presents the results of comprehensive studies of the effect of wave technologies on the physico-mechanical properties of finely dispersed montmorillonite suspensions and supersaturated salt solutions in laboratory and field conditions. It is shown that because of wave processing by flow hydrodynamic vortex-type generators with tangential and radial channels and flat-type generators with cylindrical flow bodies, the dynamic shear stress of clay solutions has increased significantly, the number of solution particles with a size of 1-2 microns has increased 2.5 times. This means that the wave treatment of the clay suspension leads to an increase in the colloidal fraction, and, consequently, to an increase in the quality of the suspension, to a decrease in the consumption of clay powder, as well as to a several-fold reduction in the preparation time compared to traditional technology. As a result of wave treatment of supersaturated salt solutions, the degree of dispersion also increased significantly: the size of salt particles in the su-persaturated solution is from 120 microns when using a conventional mechanical stirrer, and after treatment with a wave generator is 1-6 microns. It is shown that the main contribution to the achievement of high efficiency of wave processing is made by nonlinear wave and cavitation processes occurring in the flow part of hydrodynamic generators.

Diseases of the hepatobiliary system occupy a leading position among diseases of non-contagious etiology in animals. Hepatopathy of various origins cause significant economic damage to livestock farms due to a decrease in overall resistance, a decrease in productivity, as well as an increase in the cost of both therapeutic and preventive measures. The prerequisites for an increase in the number of cases of such diseases are mainly violations of the conditions of keeping and feeding animals.Bile acids are increasingly being evaluated as complex metabolic integrators and signaling factors for various metabolic disorders. Increased attention to bile acids as metabolic regulators has led to two main research questions: how do bile acid dominants change in metabolic diseases and how can the activity of bile acids be used to treat metabolic diseases? Both issues will be addressed in this review. We searched for original studies in the scientific databases PubMed, Elsevier Science (Scopus) and Clarivate Analytics (Web of Science) to identify the biochemical, signaling and target functions of bile acids, after which a formalized content analysis of the found publications was carried out. In recent years, much attention has been paid to bile acids, not only as the end products of cholesterol metabolism and the main components of bile, but also their role in a number of pathological conditions of the body. Thus, the data obtained by various researchers show that they can be markers of differential diagnosis between hepatopathy of various origins, which makes them one of the most promising diagnostic models.

Results are presented from adsorption and electrochemical investigations of a 3,7,12,17-tetramethyl-8,13-divinyl-2,18-deuteroporphyrin IX (depocolin) salt on a CuNiFe (MNZh) 5-1 alloy. It is established that modifying surfaces of copper and CuNiFe 5-1 alloy with depocolin and the subsequent adsorption of 5-chloro-1,2,3-benzotriazole considerably enhances the protective effect, which is higher than those of each compound taken separately. XPS and reflection ellipsometry reveal the chemisorptive character of interaction between depocolin and the alloy’s surface. It is shown that bonding between the inhibitor and the copper or alloy surface proceeds through carboxyl groups of depocolin, while the porphyrin cycle does not participate in this interaction.

Software for the simulation of low-speed machining based on the SolidWorks and Deform-3D CAD/CAE systems is analyzed. The following properties are established: the optimal finite-element size; the influence of epilam nanofilms on thermal processes in different machining conditions; and the influence of the frictional force on the stress at the tool’s working contact surface.

The paper presents the results of studying thermal stability of materials operating in a plasma jet under high temperature and rapid thermal load variation conditions. It has been shown that the use of plasma generators along with the introduction of various powder materials make it possible to simulate the operating conditions of the parts exposed to high-temperature gas flows containing heated particles. The effect of the introduced powder materials on the thermal stability of samples prepared by plasma spraying from molybdenum, as well as tungsten and tungsten-based compositions was studied. An experimental setup was proposed for evaluating the thermal stability of the composites and protective hardening coatings operating under high-temperature gas flows, which also allows determining erosion resistance.

Corrosion of 08PS low-carbon steel was studied in a wide temperature range t = 25—100 °C in 1 M H2SO4 + 1 M H3PO4, 2 M H2SO4 и 2 M H3PO4, inhibited by the binary mixture IFKhAN-92 + KNCS (a molar ratio of components 9:1) and a three-component mixture IFKhAN-92 + KNCS + urotropine (9:1:400), in the presence of high concentrations of Fe(III) and Fe(II) salts, as well as in their joint presence. It is shown that under experimental conditions the corrosion inhibitors under study provide effective protection of steel in 1 M H2SO4 + 1 M H3PO4 even in the presence of Fe(III), Fe(II) salts or their mixtures. The highest protective effects are provided by a three-component inhibitor mixture. Under similar conditions in individual 2 M H3PO4 and, especially, 2 M H2SO4, the protective effects of inhibitors are lower. A stronger deceleration of steel corrosion by composite inhibitors based on IFKhAN-92 in H2SO4 + H3PO4 solutions containing Fe(III) salts in comparison with similar solutions of individual H2SO4, is largely due to the binding of Fe(III) cations by phosphate anions into complexes, that significantly reduces their chemical activity and, as a result the corrosion rate of steel.