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Introduction. Wind load has a significant impact on buildings and structures. It triggers the evolution of the stress-strain state that causes various kinds of deformations. Requirements, applicable to the serviceability limit state, are important for the construction of long-span structures. In some cases, the analysis of the distribution of wind effects over the surface of a construction facility may be a challenging task. The purpose of the study is to identify the pattern of the wind load distribution over the shell of a long-span structure using physical and numerical methods, compare and analyze the obtained results. Materials and methods. In the course of the study, a model of the shell structure was tested in the wind tunnel in the course of the physical testing. The model was made of polymer materials using the 3D printing technology. In addition, the article addresses the procedure for conducting full-scale tests in a wind tunnel. Numerical modeling was performed using various software and numerical software packages, such as Ansys CFX, SOLIDWORKS. Results. The article presents the results of physical tests conducted in a wind tunnel, demonstrates the tables that have the values of aerodynamic coefficients and wind pressures, on the basis of which colour pressure isofields are made. Also, the article presents the results of iterative calculations of numerical models made using various software and numerical software packages. In addition, wind flow distributions were analyzed, since the object of the study has such a characteristic feature as an open-air shell, which allows the air flow to reach the structure from below. Conclusions. The authors analyzed the data obtained as a result of the research; the convergence between the results of physical tests and numerical modeling in Ansys CFX was identified, a great discrepancy between numerical and physical studies was identified as a result of the application of other software packages. When designing buildings and structures, having intricate geometric shape, both physical and numerical modeling should be conducted.

The objective of the study was to analyze in-hospital mortality and long-term survival of elderly patients who underwent open-heart surgery and met the criterion of frailty. Materials and Methods. The study involved 266 patients over 75 years old complying with the frailty criterion (F-index ≤5). A total of 155 operations of coronary artery bypass grafting (CABG), 47 surgeries of aortic valve replacement (AVR), and 64 procedures of CABG in combination with AVR were performed. Study subjects were distributed among the groups depending on the surgery type. Postoperative complications were evaluated, and short-term and long-term outcomes were compared. Results. In-hospital mortality was 5.3% in general group, 9.4% in CABG+AVR group, 3.9% in CABG group, and 4.2% in AVR group. There was no significant difference among the rates of in-hospital mortality between the groups (р>0.05). Long-term survival rates in general group were as follows: 98.3% for 1-year survival, 94.6% for 3-year survival, and 82.1% for 5-year survival. Type of surgery had no significant impact on the outcome (р>0.05). Conclusion. Short- and long-term effects of CABG, AVR, and combination of CABG with AVR in the group of elderly patients who meet the criterion of frailty were characterized by low mortality and low incidence of non-fatal complications. The type of cardiac surgery and old age did not affect significantly the outcome of a surgical treatment.

The paper presents data on the study results of sanitary and chemical indicators of water from the surface source and drinking water in Severomorsk for the period 20172018. The authors have revealed that the main indicators (smell, iron, pH, total hardness, chlorides, sulfates, ammonia nitrogen, nitrates and nitrites) of the water in the capital of the Northern fleet fully complies with SanPiN 2.1.5.980-00 Hygienic requirements for the protection of surface water. During the study period, there were slight fluctuations in indicators due to seasonal dynamics. The analysis of the data showed that drinking water in all areas of Severomorsk in color in 2017 exceeds the limit of MPC. The greatest excess is observed in summer. This is due to the fact that in spring and summer a large number of fulvic and humic acids, which lead to an increase in color, comes to the pond with rain and swampwaters. A direct dependence of color on iron parameters was also revealed. The iron content in drinking water for 20172018 exceeds the MAC boundary, which can be associated with water stagnation, which causes an increase in the concentrations of this indicator. The obtained data can be used in the implementation of measures to improve water treatment, drinking water treatment and allocation of the necessary funds for the implementation of the plan of utilities overhaul.