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In this paper, a physical model of the multi-element antenna arrays (MEAA) has been considered and a self-consistent numerical method for solving the problem of current distribution on the MEAA surface with chiral metamaterials substrate has been proposed. The algorithm of the input admittance matrix elements for chiral layer based on the conductive left and right-handed helices has been developed and elements of the matrix surface impedances for investigated structures have been found. A set of singular integral equations with a Cauchy kernel for calculating the current density on the surface of the MEAA has been derived. A numerical solution of the set is a well-posed in the sense of Hadamard. Calculations of current distribution on the MEAA surface, impedance characteristics of a three-element antenna array and the dependence of the isolation levels between emitters on the chirality parameter have been performed and analysed. It has been shown that the use of chiral substrates can substantially increase the isolation between emitters.

Objective: In the mortality structure of Republic of Sakha (Yakutia), about 80% of all deaths occur in the out-of-hospital setting. In these cases, treatment outcomes are directly affected by the quality of out-of-hospital resuscitation aid. The objective was to examine the treatment outcomes for patients who have survived clinical death at the prehospital stage and were taken to the hospital after their cardiac activity had been restored. Design: A retrospective analysis was done using a continuous method and method of mathematical analysis. Materials and methods: Call records and medical histories of the patients from a specialized hospital for 2014-2016 were the data source. Results: Data on the causes of death, quality of pre-hospital resuscitation aid and survival of patients who had a clinical death out of the hospital were obtained. Cardiac activity was restored in 23.4% (602 resuscitation procedures). The causes of death were as follows: sudden cardiac death (40%), accidents (32.0%) and acute cerebrovascular accident (9.6%). A low survival level was found at the hospital stage (17.6%). A direct dependence between the survival of patients and clinical death (resuscitation activities) duration was confirmed. Conclusion: A low survival level following pre-hospital sudden cardiac arrest was found during the study. Out of 602 patients who underwent resuscitation activities, 22 (3.7%) of patients survived. The article can be useful in finding the shortcomings at the stages of resuscitation aid provision and developing organizational technologies to increase the effectiveness of resuscitation. [ABSTRACT FROM AUTHOR]

Background: The mortality rate from external causes in the Sakha Republic (Yakutia) is higher than the average figure for the Russian Federation as a whole. Aim of the research: to study the sex-specific trends in mortality from external causes in the Sakha Republic (Yakutia) in the period 2016-2018. Research Design: A retrospective comparative analysis of the sex-specific trends in mortality from external causes among the population in Yakutia in 2016-2018 was carried out basing on the official statistics data. Materials and Methods: Official data from the Federal State Statistics Service were studied. For fatal road traffic injuries, data from the General Administration for Traffic Safety of the Russian Federation were used. To study the mortality from cold injuries, we selected code 302 in ICD-10 (Exposure to excessive natural cold). Results and Discussion: The study revealed improvements in mortality among the population of Yakutia from all types of external causes, the exceptions being traffic accidents and accidental drowning. Working-age men still account for a great share in violent deaths (74.7% of suicides and 77.7% of homicides). In 2016-2018, human mortality from cold injury ranked third in the structure of external causes of death (suicide-20.9%, homicide-13.4%, cold injury-11.4%). For all the causes looked at, the mortality rate for men is several times higher than for women. Conclusions: The improvements in mortality from external causes demonstrate different trends. Among the negative ones, it is the sustained high rate of violent deaths above the average figure for the Russian Federation. The mortality rate of the male population in Yakutia from violence, as well as accidental drowning and cold injury remains critically high. [ABSTRACT FROM AUTHOR]