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Measurements results on the shear stresses of surface friction by means of thin-film coatings based on holesteric liquid crystals and specialized software for digital processing of experimental video are presented in the paper. The calibration dependencies of shear stress relative to the hue and azimuth angle as well as shear stress spatial distribution at subsonic turbulent flow (V_∞ = 84 m/s) around a step, trapezoidal in plane (Reynolds number calculated for step height h, Re_h = 2.57×10⁴), with a base angle of 46° were derived for two geometries of experiment. The experiments demonstrated high sensitivity of liquid crystals to rearrangement of the near-wall flow structure and possibility to obtain quantitative data about mean shear stress levels.

We present the results of flow visualization and velocity measurements on a hexagonal structured surface. Several configurations with concave and convex hexagonal structures are investigated. Each hexagonal structure is 2.7 mm deep and 33 mm wide (width between flats) and has a height to diameter ratio of 0.05 based on equivalent diameter. Considered are flow velocities 19 m/s, 24 m/s, and 27 m/s. The flow bifurcates on the leading edge of the concave configuration into two counter rotating vortices and propagates further in streamwise direction. The circulating regions are identified by the peaks in r.m.s. velocity curves. In case of concave configuration, the flow splits up into counter rotating vortical structures in a vertical plane parallel to the flow. The lower vortex rotating in the opposite direction of the flow cause the oil film fringes to drift upstream. Complex circulating regions similar to the arrangement of slices in an orange can be observed on the trailing edge of the concave hexagonal structure.

Numerical modeling of heat exchange at a laminar stationary and pulsatile flow in rectangular channels with different aspect ratios of side lengths γ has been carried out by a finite difference method for two boundary conditions: a constant wall temperature and a constant heat flux density on the wall. For the boundary condition of the first kind, the similarity of distributions of the heat flux density and shear stress on the walls over the channel perimeter has been established. The reasons for a nonmonotonous dependence of the initial thermal interval length on γ are discussed. For the boundary condition of the second kind, the difference of the Nusselt number averaged over the peri-meter at γ → 0 from its value for a flow in a flat channel has been explained. An increase in the Nusselt number averaged over the perimeter and the period of oscillations has been revealed for a pulsatile flow in the quasi-stationary regime at large amplitudes of the oscillations of the velocity averaged over the cross section.

The regularities of interaction of drops of ultra-high vacuum liquid working media of space drop emitters with surfaces of trapping devices were considered. Their comparison with the characteristics of the interaction of drops of distilled water was performed. The achievability of trapping regimes without secondary drop formation in space was justified.

Objective. Currently increasing attention to the parameters of central aortic pressure (cAP). The study associations of cAP, its augmentation and amplification, with a number of metabolic parameters in the general population of Novosibirsk is of interest. Material and methods. The study involved 327 people: 155 men and 172 women aged 25-44 years from a representative sample of the general population of Novosibirsk. The research program included anthropometry, blood pressure measurement and biochemical analysis of blood serum. Central hemodynamic parameters were determined using SphygmoCor system. Metabolic syndrome components were determined according to the criteria of RSC 2009. We used the methods of descriptive statistics and analysis of data in the general linear model (GLM). Results. Systolic cAP was associated with waist circumference, triglycerides and blood glucose levels independently of other metabolic parameters, sex, age, height and heart rate. Diastolic cAP was associated with the waist circumference, triglycerides, blood glucose and low density lipoproteins levels. Triglycerides level was also associated with central augmented pressure, heart rate corrected central augmented pressure and non augmented amplification of systolic pressure. Central aortic hypertension was associated with abdominal obesity and hypertriglyceridemia, regardless of other metabolic syndrome components, sex, age, height and heart rate. Central aortic pressure in persons with abdominal obesity was 109/79 mm Hg, in the group of persons with hypertriglyceridemia - 110/78 mm Hg. Conclusion. In the general population of Novosibirsk residents 25-44 years independent determinants of central aortic pressure were waist circumference, triglycerides, low density lipoproteins and blood glucose levels. Triglycerides level was also independently associated with central augmented pressure, heart rate corrected central augmented pressure and non augmented amplification of systolic pressure. Central aortic hypertension was independently associated with abdominal obesity and hypertriglyceridemia.

Aim: to investigate clinical, functional and biochemical characteristics of patients with different ultrasound patterns of carotid atherosclerosis. Material and methods. The study included 96 hypertensive patients with carotid atherosclerosis, 55 men and 41 women (mean age 60.3±9.31 years). The first group involved 71 patients with plaque in the carotid arteries and IMT greater than 0.9 mm, the second - 25 patients with plaque and IMT less than 0.9 mm. Evaluation of cognitive impairment was performed using a Mini-Mental State Examination (MMSE). We evaluated lipid panel, markers of subclinical inflammation: high-sensitivity C-reactive protein (hs-CRP), IL-1β, IL-6, IL-8, IL-10, TNF-α. Weperformed the probe with endothelium-dependent vasodilation by D.S. Celermajer and duplex scanning of the carotid arteries and lower limb arteries. Results. Among the first group of patients was significantly greater proportion of patients with diabetes mellitus (DM) type 2 and they had significantly higher body mass index (BMI). Also in the first group was significantly lower MMSE score (p = 0,02) and was significantly higher the part of patients with mild cognitive impairment (p = 0.01). IMT values in the femoral arteries were significantly higher in the first group. Patients of the first group had significantly higher values of atherogenic lipoproteins. Patients of the first group had a significantly lower response to dilatation of the brachial artery and was significantly greater the part of patients with endothelial dysfunction - 42 (59 %) versus 11 (44 %) (p = 0.02). In patients with plaque in the carotid arteries and normal IMT revealed significantly higher levels of IL-1β and IL-6. Conclusion. Patients with plaque in the carotid arteries combined with an increase in IMT were significantly higher cholesterol levels of atherogenic lipoprotein fractions, higher BMI and a greater frequency of endothelial dysfunction. In this subpopulation of patients had more severe cognitive impairment. Patients of the second group had significantly lower values of IMT in lower limb arteries and significantly greater levels of circulating IL-1β and IL-6.

Objective: To determine the risk of developing diseases associated with atherosclerosis (myocardial infarction and stroke) in men and women with vital exhaustion in general in population 25-64 years in Russia / Siberia. Material and methods: In the III screening WHO program «MONICA-psychosocial» surveyed a random representative sample of the population aged 25-64 in Novosibirsk in 1994 (men = 657, women = 870). The program screened survey included: registration of socio-demographic data, identification VE. For a 16 year period it revealed a myocardial infarction (MI) and stroke in women cases (15 and 35) and male (30 and 22). Results. VE level were: men 66.8 % (-14.6 % high), 75.7 % in women (44.4 % higher). The risk of MI among men with VE was HR=2. We did not get the effect of VE on the risk MI among women. RR of MI in persons with VE were higher among divorced women HR = 5.4, than men HR = 4.7. Risk MI was higher in men with VE: primary education HR = 2.2; have never married HR = 3.7, widowed male HR = 7, in 45-54 years HR = 3.8 and HR = 55-64 5.9. In women, these associations have been identified. Risk of stroke in patients with VE were higher in women HR = 3.34, than men HR=3.1. Risk stroke was higher only in men with VE: with incomplete secondary - primary education HR = 4.8; men, divorced HR = 3.8, widowed men at HR = 3.6. Risk of stroke among people older than 55 years was higher in women HR = 2.9, than men HR = 2.4. Conclusion: Prevalence of VE was higher in women than in men. Vital exhaustion is a predictor of MI in men and stroke in both genders. VE has a large prevalence among the population aged 25-64 years, and higher in women than in men. VE is a predictor of atherosclerosis-associated diseases: myocardial infarction greater in men than in women and stroke in both sexes.

Purpose: The patterns of findings in a fundus in cardiovascular (СVD) and chronic non-communicable diseases have been investigated in European and North American populations with heterogeneous results. The subject has not been practically studied in Russian population. We performed systematic literature search for 15 years (2001-2015) to summarize the data from published studies on the relationship between fundus abnormalities and CVD and its’ complications. Methods. We used the Internet resources: PubMed (http://www.ncbi.nlm.nih.gov/pubmed/), Scopus (http://www.scopus.com), e-library (http://elibrary.ru/defaultx.asp) and major domestic cardiological, therapeutic and ophthalmologic journals. Results. The analysis of the data accumulated in the literature showed the associations between specific patterns of fundus abnormalities and CVD, and also a prognostic impact of these changes on the development of complications of CVD. Namely are shown: the association between a narrowing of arteries and dilation of veins and the risk of ischemic heart disease and fatal CVD; the association between an increase of vein diameter and the risk of a cerebral stroke; the relationship between fundus changes and aging and risk factors of CVD; the contribution of ophthalmoscopic identification of fundus abnormalities to the stratification of cardiovascular risk.

The article is devoted to the current state of the problem of statin use in interventional cardiology. It is shown that the use of statins in patients with stable manifestations of coronary heart disease, and in patients with acute coronary syndrome has a protective effect, which is reflected in the reduction of perioperative myocardial ischemia, improvement of left ventricular systolic function, reducing the number of adverse cardiac events. It is known that the protective role of statins is associated not only with the cholesterol-lowering effect, but also with a large number of pleiotropic effects. A lot of attention is paid to the complex and problematic group of patients with chronic total occlusions of coronary arteries (CTO). The presence of CTO is associated with poor prognosis and increased mortality in long-term period. A significant problem during percutaneous coronary intervention (PCI) in patients with the CTO is a frequent development of perioperative ischemia or myocardial infarction, which is associated with an increased mortality rates within 30 days after PCI, as well as in the long-term period. Currently, mostly proved protective effect of atorvastatin. Based on the analysis of contemporary literature is concluded that statin efficacy in the prevention of complications of PCI in patients with CTO is currently not in doubt.

The review systematized modern concepts of markers of endothelial dysfunction and disorders of hemostasis (asymmetric dimethylarginine, endothelin 1, adhesive ICAM and VCAM molecules, apolipoproteins, antithrombin III, receptor of urokinase plasminogen activator, tissue factor pathway inhibitor, blood coagulation factors VII, XII, prothrombin) associated with atherogenesis, and genes responsible for their regulation.