A kinetic description of electron beam ejection from spacecraft

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94997/1/grl7005.pd

The Concept of Theoretical-Empirical Dualism in Teaching Math

Among the problems of mathematical education, the article highlights: (1) insufficient attention paid to the fundamental, structure-forming role of mathematics; (2) speculative learning, its isolation from practice. The concept of theoretical-empirical dualism in teaching is formulated as the unity of the abstract-theoretical and experimental-empirical cognitive activity of students. According to the author, a priori and a posteriori mathematical knowledge should be distinguished. A priori knowledge either seems to an individual to be completely obvious, indisputable, or he assimilates it uncritically, “on faith”. A posteriori mathematical knowledge subjectively arises in the process of student’s intense theoretical and practical activity, and is being actively and comprehensively verified experimentally – either using mathematical applications, or through mathematical experiments. The empirical component of teaching mathematics implies a variety of forms and methods of active (including computer) and professionally oriented learning, giving experience in independent formulation of problems, joint search for ways to solve them, interaction and teamwork. Particular attention is paid to the use of mathematical experiments in those frequent cases when it is necessary to replace or supplement complex evidence, illustrate new knowledge, and give research skills. Monte Carlo mathematical experiments are demonstrated, which serve, in particular, as a bright, figurative, and convincing form of reinforcing theoretical knowledge in the field of stochastic branches of mathematics. The research work of students is considered as the highest stage of the students’ theoretical-empirical activity. The article proposes subjects of research activities of students in the process or upon completion of the study of probabilistic and statistical disciplines

Experience in Studying Seroprevalence to SARS-CoV-2 Virus in the Population of the Irkutsk Region during COVID-19 Outbreak

Objective of the seroepidemiological study was to determine the level and structure of herd immunity to SARS-CoV-2 among the population of the Irkutsk Region during the period of an increase in the incidence of COVID-19.Materials and methods. The content of antibodies to SARS-CoV-2 was determined by ELISA applying a  reagent panel “ELISA anti-SARS-Cov-2 IgG” produced by the State Scientific Center of Applied Microbiology and Biotechnology (Obolensk).Results and discussion. The investigation has revealed that the herd immunity of the total population of Irkutsk Region amounted to 5.8 %. The greatest share of seropositive persons was among the children aged 14–17 (13.8 %) and 1–6 (11.8 %). It has been established that the risk of infection increases by 3.1 times in case of contact with COVID-19 patients. After exposure to COVID-19, antibodies were produced in 56.5 % of the cases. The share of asymptomatic forms among seropositive residents of the Irkutsk Region reached 81.2 %. Consequently, during the chosen period of increased COVID-19 incidence among the population of Irkutsk Region low level of seroprevalence was formed. A significant proportion of asymptomatic forms of infection characterize high intensity of the latently developing epidemic process. The results obtained can be used when organizing preventive measures, including vaccination, and for forecasting morbidity rates