This article is an introduction to the description and analysis of the electronic correspondence of the author with I.S. Kon, held in 2005-2011. Kon belongs to a narrow group of sociologists who stood at the origins of Soviet sociology. For many years, Kon has successfully worked in different areas of sociology, at the same time he is a recognized expert in the history of Russian and Western sociology. All this: 1) makes Kon a unique expert in the field of studying the entire period of development of Russian sociology, and 2) determines the historical, sociological and methodological value of his letters. Let us pay attention to the fact that the study of the correspondence of sociologists is a poorly studied topic, but there is a tendency to increase attention to it. The total number of letters is about 200. The texts of 39 letters for 2005-2006 are given. The history of correspondence and its content is briefly considered.

The article attempts to examine the modernity through the prism of the transition of communities from the natural-historical to the socio-historical type of development. Convergence of various social systems is one of its most important trends. It is determined by a number of reasons, primarily the fact that the sustainable preservation of society in modern conditions is ensured by its development. Reforming of various countries mainly Russia and China is analyzed from the standpoint of convergence as a turbulent process. It is shown that the implementation of this trend contributes to the solution of current economic and social problems and its ignoring leads either to the immature forms of socialism or to the neoliberal model with all its negative consequences.

The article deals with environmental obstructions and limitations for a dynamic political and socioeconomic development of modern Russia. Environmental problems accumulated in the past decades, including problems that appeared in the "Soviet" period of the country's development, together with growing new environmental risks, become a serious obstacle to the progressive development of the country. Contemporary Russian manufacturing practices continue to use extensively anti-environmental obsolete technologies, which lead to increasing degradation of the natural environment and an increase in negative trends in the health of the population. The absence or limited use of remediation activities in extractive industries has led to the natural degradation of a number of territories in the country. Unfavorable socio-demographic characteristics of the development for modern Russia caused by the environmental factors hinder innovative development in all spheres of society in the present period; moreover, their increasing impact will be an obstacle to socio-economic development in the future. Additionally the article discusses long-term negative trends in the development of environmental policy and weakening of the ecological spectrum of civil society.

The article presents the cognitive capabilities of online surveys for studying narrow, hard-to-reach target groups. The key issue of a survey conducted with specific audiences is respondents' search and involvement. The authors measured the response rate of labor migrants and people with disabilities according to the findings of the methodical analysis of two online surveys. The article proposes an algorithm of response rate measurement by internal and external parameters. Primary focus is on comparing the effect of using targeted advertising on Facebook and Yandex; the perception of advertising banner analysis in the context of survey's successful finishing; the calculation of response rate and several other indicators. The results of the methodical research indicate the most effective ways of audience involvement in online surveys, the importance of the questionnaire design, especially the first question. The main conclusion is that the test method provided with a set of conditions can be used for studying narrow target groups.

Today's patients and/or their relatives periodically appeal to the Internet, its various resources in the disease situation. The information and communication capabilities of the Internet modify the traditional "role of the patient" and the patient community, significantly affect the medical choices, that patients make at different stages of the disease. In 2018, research focusing on the medical choice of patients with chronic diseases in Samara was conducted at Samara University. This paper describes the results regarding the use of the Internet by Samara patients with chronic diseases. First of all, we are talking about the distribution of the use of the "medical Internet" by gender, age and level of education, the goals of accessing the Internet in a situation of disease, and which Internet resources are used.