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Various issues of numerical simulation of supersonic gas flows with allowance for thermochemical nonequilibrium on the basis of fluid dynamic equations in the two-temperature approximation are discussed. The computational tool for modeling flows with thermochemical nonequilibrium is the commercial software package ANSYS Fluent with an additional user-defined open-code module. A comparative analysis of results obtained by various models of vibration-dissociation coupling in binary gas mixtures of nitrogen and oxygen is performed. Results of numerical simulations are compared with available experimental data. 

The aim of this study is to investigate numerically the effects of four vortices on the dynamic, scalar, and turbulent fields of the hydrogen jet. These vortices, which appear in the vicinities of the nozzle, are created by the vortex generators (VGs), and they are assembled with periodicity or symmetry in order, respectively, to give four vortices of the same or opposite direction. A second-order Reynolds stress model is used to investigate asymmetric turbulent jet. The results indicate that the presence of the vortex near the emission jet section noticeably enhances mixing to ensure a good combustion.

A supersonic air flow in a plane channel with a transverse turbulent jet of hydrogen injected through a slot on the bottom wall is simulated. The algorithm for solving the Favre-averaged NavierStokes equations for the flow of a perfect multispecies gas on the basis of the WENO scheme is proposed. The main attention is paid to the interaction of the shock-wave structure with the boundary layers on the upper and lower duct walls under the conditions of an internal turbulent flow. Namely, a detailed study of the structure of the flow is done, and separation and mixing depending on the jet slot width are investigated. It is found that in addition to well-known shock-wave structures produced by the interaction of the free stream with the transverse jet and the bow shock interaction with the boundary layers near the walls, an additional system of shock waves and the flow separation arise on the bottom wall downstream at some distance from the jet. The comparison with the experimental data is performed.

A method of formation and heating of СО₂ as a test gas in the settling chamber of a hotshot wind tunnel is considered. To form and heat СО2, the chamber is filled with a source gas mixture of СО, О₂, and СО₂, and after initiation, these substances participate in an exothermic chemical reaction in accordance with the formula СО + 0.5 О₂ + х СО₂ = (1 + х)СО₂. A stoichiometric ratio of the concentrations of carbon monoxide CO and oxygen is used. Variation of the number of moles x of ballast CO₂ in the left part of the chemical formula allows changing the temperature of the resultant test gas in a wide range. Experiments in the IT-302M hotshot wind tunnel carried out at ITAM SB RAS have shown that a pressure increase during an isochoric process in the settling chamber due to the joint effect of heat released in the reaction СО + 0.5 О₂ and an electric charge provides the completeness of CO combustion almost equal to unity. The time of reaction completion at its initiation by an electric arc is no more than several milliseconds.

In the present paper, results of numerical simulation of single-phase flows of heat carrier through square and triangular rod bundles are reported. The simulations were aimed at the determination of parameters involved in an integral model of turbulence being developed for modeling nuclear-reactor cores and heat exchangers in anisotropic porous-body approximation.

The aim of this study was to investigate the connection between coronary atherosclerosis severity, measured on a scale of the SYNTAX with psychosocial factors in patients with acute coronary syndrome who live in the North. The study involved 269 consecutive patients (n = 203, 21.2% female, n = 66, 78.8% - men) with acute coronary syndrome with the average age of 56,0 ± 6,1 years (45-64 years). It revealed a high level of alcohol consumption on the AUDIT scale in patients with severe coronary disease compared with mild and moderate (p = 0.03). Direct correlation among severity of coronary lesions, a total cholesterol (r = 0,15, p <0,05) and low density lipoprotein cholesterol (r = 0,15, p <0,05) in patients with severe coronary disease were found out. With the help of binary logistic regression it was stated that the low level of instrumentally support increases in 2,16 times the risk of presence of acute coronary syndrome ona scale of the SYNTAX (p = 0,02), however, the age (p = 0.06) and male gender (p = 0 94) did not significantly influence the dependent variable above.

Objectives: to investigate the prevalence and determinants of AF in cross-sectional study in a population sample 45-69 age (Novosibirsk). Materials and methods: a random population sample of men and women 45-69 years old (y. o.) (n=9360) was examined in Novosibirsk (project HAPIEE). We used standard epidemiological methods. As optional study ECG was registered participants and estimated by Minnesota code (n=9255). They were included for current analysis (grant RSF 14-45-0030). Results: in studied population sample the prevalence of AF was 1.6% (1.1% in women and 2.1% in men). The frequency of AF increased with age: from 0.3% in age group of 45-49 y. o. in both sexes to 4.0% in men and 2.8% in women in the oldest age group (65-69 y. o.), p<0.001. In unadjusted analysis, in men AF was associated with elder age, heart rate (HR) (р<0,001), diastolic blood pressure (р=0,003), body mass index (BMI) (р<0,001), presence of cardiovascular disease (CVD), hypertension (HT) (р<0,001) and diabetes mellitus (DM) (р=0,002). When we have compared laboratory parameters, the patients with AF had lower level of total cholesterol (TC) (р=0,001), low-density lipoprotein cholesterol (LDL-C) (р=0,005) and higher level of gamma-glutamyltranspeptidase (GGT) (p <0.001). The significant difference of alcohol consumption measures in relation to AF we did not identified in population sample. In women were similar results in the studied risk factors and cardiometabolic diseases. In multivariate regression, AF in men was positively associated with age, HR, BMI (p<0.001) and negatively related to level of triglycerides (p=0.019) and LDL-C level (p=0.001). Women had a positive association of AF with age, HR, BMI (p<0.001), GGT (p=0.002) and negative - to LDL-C level (p<0.001). Conclusions: in a population sample 45-69 y. o. of Novosibirsk the prevalence of AF was 1.6%, which is close to indicators in other populations. Determinants of AF were CVD, HT, DM, HR, BMI, increasing age (for both sexes) and GGT level in women. We did not find the direct relationship between AF and the atherogenic lipid profile; these results are likely to be associated with the modulating contribution of cardiometabolic factors.

Clinical examination in our country has a long history. National health care has significant experience in the clinical examination of the population and its separate contingents. Cardiovascular disease is one of the priorities for preventive measures among the population. During the event, using the experience, formed the modern concept of the clinical examination of the adult population.

Atherosclerosis concept defines the key role of inflammation in the occurrence and progression of atherosclerosis. Hemostatic system is an integral part of the inflammatory response. At all stages of atherogenesis, starting from the early stages, there is part of hemostasis factors. In recent years researchers attract most interest to the questions of intercellular interaction between platelets and leukocytes. Combined evaluation of leukocyte-platelet responses reflect the clinical and laboratory picture of atherothrombotic events in unstable angina and myocardial infarction. Monocyte-platelet interaction plays a significant role in the development of heart failure, blood platelets are capable of inducing apoptosis. The individual testing the risk of hemorrhagic complications increase the efficiency of drug prevention and therapy of antithrombotic drugs. Changing the pattern of atherosclerosis observed in recent years, also requires the introduction of new approaches in the prevention of atherosclerosis, enhancing the protection of the endothelium. This review focuses on the research, covering the role of hemostasis in the pathogenesis of atherosclerosis.

The 84rd European Atherosclerosis Society (EAS) Congress was held in Innsbruck, Austria, 28 May-1 June 2016. The Congress program discussed the latest scientific data and clinical studies. Angiogenesis and vascular metabolism, familial hypercholesterolemia, obesity, lifestyle and cardiovascular diseases, personalized medicine were the main topics of the discussion. The review was prepared based on the EAS Congress 2016 materials and the websitehttp://www.eas2016.kenes.com/.