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The aim of the study was to assess the zinc content and identify the relationship between the concentration of this element and changes in the biochemical status of patients and markers of inflammation during burn shock. We examined 23 patients aged 45.3±16.1 years with burns of I-II-III degree, area of 31-80%. The serum concentrations of zinc, albumin, interleukin-6, C-reactive protein (CRP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined. The majority of patients (21/23) had severe hypocincemia, correlated with burn area (r=-0.53; p=0.008). A decrease in zinc levels during burn shock was associated with the development of hypoalbuminemia (r=0.52, p=0.01). The association of deviations in ALT and AST activity with changes in zinc concentration was revealed (-0.59

A new design of horizontal pivoting pile anchors used as supports for main pipelines on heaving and watered bases is proposed. The purpose of the design is to reduce the deformability of this type of Foundation and increase its load-bearing capacity under the influence of the forces of frost heaving of the soil. Stamp tests of models of piles with rotary anchors were performed on the stand for testing Foundation models of NPP GEOTECH. Based on the test results, the effectiveness of using piles with the location of their rotary anchors at one and two levels along the trunk was compared, and the reduction in the load-bearing capacity of the pile with an unfavorable location of the anchors was determined. It is shown that according to the results of stamp tests, the rotary anchors of piles positively affect the operation of the Foundation. The use of rotary anchors in one level increases the load-bearing capacity of the pile by 16 % and reduces shrinkage by 40 % compared to a pile of the same size, but without anchors. The use of anchors in two levels increases the load-bearing capacity of the pile by 73 % and reduces the draft by 48 %. The advantage of a pile with two levels of anchors compared to its own with one level of anchors is 48 % in terms of load-bearing capacity and 11 % in terms of draft. The use of rotary pile anchors can significantly increase the reliability of the foundations of main pipelines on heaving and watered bases. This design solution is more efficient than similar metal piles with vertical anchors at equal cost levels.

The state of the hemostasis system was studied in 9 patients of the middle age group (44 ± 9.94 years) who received thermal trauma on an area of more than 32% (49.4 ± 18.3) of the body surface, accompanied by the development of burn shock. The standard therapy for burn injury was supplemented with HBO sessions. Treatment with hyperbaric oxygen was carried out in pressure chambers BLKS-307, BLKS-307/1. The state of the coagulation, anticoagulant and fibrinolytic links of the hemostasis system, as well as the viscoelastic properties of the blood, were assessed immediately before the HBO session and immediately after it. The total number of comparison pairs was 45. Under the influence of HBO therapy, there was an increase in the activity of antithrombin III (ATIII), protein C (PrS) and a decrease in the viscoelastic properties of blood (p

A wide range of studies have demonstrated that hyperhomocysteinemia is associated with the risk of schizophrenia, but currently available assumptions about the direct involvement of homocysteine (Hcy) in the pathogenesis of schizophrenia are hypothetical. It is possible that in vivo Hcy is only a marker of folate metabolism disturbances (which are involved in methylation processes) and is not a pathogenetic factor per se. Only one study has been conducted in which associations of hyperhomocysteinemia with oxidative stress in schizophrenia (oxidative damage to protein and lipids) have been found, and it has been suggested that the oxidative stress may be induced by the elevated Hcy in schizophrenic patients. But the authors did not study the level of reduced glutathione (GSH), as well as possible causes of hyperhomocysteinemia—disturbances of folate metabolism. The aim of this work is to analyze the association of Hcy levels with the following: (1) redox markers in schizophrenia GSH, markers of oxidative damage of proteins and lipids, and the activity of antioxidant enzymes in blood serum; (2) with the level of folate and cobalamin (В12); and (3) with clinical features of schizophrenia measured using the Positive and Negative Syndrome Scale (PANSS). 50 patients with schizophrenia and 36 healthy volunteers, matched by sex and age, were examined. Hcy in patients is higher than in healthy subjects ( p = 0.0041 ), and this may be due to the lower folate level in patients ( p = 0.0072 ). In patients, negative correlation was found between the level of Hcy both with the level of folate ( ρ = − 0.38 , p = 0.0063 ) and with the level of B12 ( ρ = − 0.36 , p = 0.0082 ). At the same time, patients showed higher levels of oxidative modification of serum proteins ( p = 0.00046 ) and lower catalase (CAT) activity ( p = 0.014 ). However, Hcy is not associated with the studied markers of oxidative stress in patients. In the group of patients with an increased level of Hcy (>10 μmol/l, n = 42 ) compared with other patients ( n = 8 ), some negative symptoms (PANSS) were statistically significantly more pronounced: difficulty in abstract thinking (N5, p = 0.019 ), lack of spontaneity and flow in conversation (N6, p = 0.022 ), stereotyped thinking (N7, p = 0.013 ), and motor retardation (G7, p = 0.050 ). Thus, in patients with schizophrenia, hyperhomocysteinemia caused by deficiency of folate and B12 is confirmed and can be considered a marker of disturbances of vitamin metabolism. The redox imbalance is probably not directly related to hyperhomocysteinemia and is hypothetically caused by other pathological processes or by an indirect effect of Hcy, for example, on the enzymatic antioxidant defence system (CAT activity), which requires further exploration. Further study of the role of Hcy in the pathogenesis of schizophrenia is relevant, since the proportion of patients with hyperhomocysteinemia is high and correlations of its level with negative symptoms of schizophrenia are noted.

Disorders of the hemostatic system and inflammation play a key role in the pathogenesis of new coronavirus pneumonia (NCP), determining its course and outcome. To study the dynamics of the state of the hemostasis system and the severity of the acute phase response in patients with new coronavirus pneumonia. We determined APTT, prothrombin time (PT), fibrinogen (F), D-dimers (D-d), antitrombin III (AT III), C-reactive protein (CRP), platelet count in 22 patients. In 49 patients, the viscoelastic properties of a blood clot were studied by thromboelastography (TEG) with koalin. The age of the patients ranged from 40 to 77 years. According to CT, the severity of 100% cases corresponded to CT2-CT3. Acute respiratory failure (ARF) was diagnosed in 16 patients. A control group included 25 apparently healthy subjects. During hospitalization, patients with NCP were characterized by: an increase in the concentration of D-d, CRP, Fg, lengthening of APTT and PT, ATIII activity and platelet count not differing from the normal range. 10 days after hospitalization and against the background of ongoing therapy, patients with NCP showed positive dynamics in the hemostasiological profile and the severity of the inflammatory response. Thromboelastography indices in patients with LCP did not differ from control values both at hospitalization and on day 10.Thus, in patients with novel coronavirus pneumonia, an increased prothrombotic activity and a pronounced inflammatory response are recorded. Against the background of treatment, there is a positive dynamics in both the coagulation status and the inflammatory response. Additional studies are needed to determine the diagnostic capabilities of thromboelastography in patients with NCP.

The article presents results of research on adhesive properties of aortic crescents (endothelial and subendothelial surface) obtained with the use of atomic force microscopy and specially created hydroxyapatite-based probes along with results of identification of the chemical composition of deposited calcium salts in patients with calcified aortic stenosis. The results of the study are supposed to be of pathogenetic significance for understanding the development of calcified aortic stenosis. The proposed method for creating specialized probes for atomic force microscopy can be used in the modeling of processes of ectopic calcification of other organs and system.

The article describes design of a pile with new rotary anchors for foundations of buildings operating on variable loads or on heaving soils. The results of plate load tests on piles’ pressing in with one- and two anchor levels are presented. Based on calculations on bearing capacity of piles of proposed design, the adequacy of data on determination of its bearing capacity obtained by experimental method is calculated. Bearing capacity of anchor piles for pulling out is determined by calculations. Anchors located at one level at the height of pile increase its bearing capacity for pressing in by 20%, and increase it for pulling out by 94%. Anchors located at two levels at the height of pile increase bearing capacity of pile for pressing in by 60%, and increase bearing capacity for pulling out by three times. A decrease in the settlement of pile of proposed design is determined by the results of plate load tests on pressing in and it amounts to 85% for a pile with one-level anchors and to 94% for a pile with two-level anchors.

A numerical approach to investigation of static and dynamic characteristics of fuel reservoir and surge-protection capacity with cracks in welded joints of their walls has been proposed. Mathematical modeling of the nonlinear behavior of the complex shell structure has been performed under the action of static vertical loading using the software complex of finite element analysis. The models of cracks with different length within vertical and horizontal welded joints of shell walls have been developed. The influence of cracks on the stress-strain state and stability of the fuel reservoir as well as the surge-protection capacity has been investigated. The dynamic characteristics of the structure have been determined, the influence of cracks on the frequencies and the modes of their natural vibrations has been evaluated.

The authors put forward a numerical approach to determination of nonlinear bending stability of a long flexible cylindrical shell with geometrical imperfections. The shell wall imperfection in the form of bulging in long half-wave is modeled using a software package for finite-element analysis. Prebuckling and postbuckling behavior of an imperfect shell in bending is studied. The critical normal stress in the shell compression zone is plotted vs. the imperfection amplitude. The bending stability region is determined for a shell with geometrical imperfections.

A probabilistic approach to reliability analysis for stability of an imperfect supporting shell has been elaborated. The nonlinear stability of the shell under combined loading conditions is analyzed taking into account the shell imperfection. A surface of critical load combinations has been constructed and a field of stability has been defined. The stability reliability has been determined allowing for various types of distribution in frequency of the shell imperfection and its maximum possible preset value through the use of reliability surface. The authors have derived allowable combinations of complex loadings that should be taken into consideration during the design and operation of a supporting shell.

A numerical method for investigating stability of the supported cylindrical shell with account for geometric imperfection in the form of its deformation during in-service loading has been developed. The problem of nonlinear stability of the imperfect supported cylindrical shell under combined loading has been solved. The influence of the imperfection amplitude on the critical combination of loads and stability region of the supported shell has been evaluated. Introduction. Supported cylindrical shells find widespread use in many engineering fields such as industrial engineering, food, chemical and other industries. One of the main features required of these structures is the ensuring of their minimum weight with sufficient strength and stability. It can be fulfilled provided that geometric nonlinearity, which is typical of the structures with openings, stiffening rings or ribs on their surface operating under conditions close to boundary ones, is taken into consideration during the investigation of their load-carrying capacity and stability. The problem of evaluation of the influence of geometric imperfection on the stability of shell structures remains topical (1-9). Use of analytical methods involves the form of geometric imperfection of the supported shell to be expressed as trigonometric functions, which considerably narrows the focus of investigations. With the availability of modern calculation systems it is possible to express geometric imperfections arbitrarily (10-13), which enhances the physical understanding of the behaviour of imperfect shells. Despite widespread use of supported shells in engineering practice, the influence of imperfections on stability, especially under combined loading, has not been fully investigated. The paper is devoted to the solution of the problem of stability of the imperfect supported shell under wind loading with account for alternating pressure from the weight of the tank filled with liquid, which is placed at the top. A numerical approach, which is based on the finite element method and nonlinear analysis of stability of the shell with geometric imperfections in the form of its deformation, has been proposed. The limiting values for stress-strain state of the supported shell as well as critical values of combined loading, under which its overall stability conditions are fulfilled, have been determined. The influence of geometric imperfection of the supported shell on the critical values of combined loading and its stability region has been evaluated. Development of the Finite Element Model for the Supported Shell Considering Geometric Imperfection. The shell is a cylinder with two openings, which are reinforced with stiffening ribs. The shell walls are reinforced with vertical stiffening ribs at the top and with lower and upper rings. The shell has the following geometry: diameter D 56 1 . m, height H 53 . m, and wall thickness t 10 mm. The rings take the shape of a plate with width of 200

Platelet aggregation and prooxidant and antioxidant potentials were studied in patients with burn more than 20% total body surface area for 30 days after injury. There were progressive increases in platelet aggregation, lipid peroxidation, and antioxidant activity. The possible pathogenetic aspects of the findings are discussed.

It is determined that during compression and decompression of blood and blood suspension the main section plane of naturally sedimented erythrocytes assume virtually vertical position and, therefore, sedimentation rate of erythrocytes rises. Also, following compression blood density in vitro is irreversibly increased. The idea of existence of erythrocyte-bonded gas microcavities is discussed.