The preventive destruction of a hazardous asteroid

One means of countering a hazardous asteroid is discussed: destruction of the object using a nuclear charge. Explosion of such an asteroid shortly before its predicted collision would have catastrophic consequences, with numerous highly radioactive fragments falling onto the Earth. The possibility of exploding the asteroid several years before its impact is also considered. Such an approach is made feasible because the vast majority of hazardous objects pass by the Earth several times before colliding with it. Computations show that, in the 10 years following the explosion, only a negligible number of fragments fall onto the Earth, whose radioactivity has substantially reduced during this time. In most cases, none of these fragments collides with the Earth. Thus, this proposed method for eliminating a threat from space is reasonable in at least two cases: when it is not possible to undergo a soft removal of the object from the collisional path, and to destroy objects that are continually returning to near-Earth space and require multiple removals from hazardous orbits

THE EGALITARIAN PRINCIPLES OF THE OLD BOHEMIAN STATEHOOD AND THE LEGAL SYSTEM

Purpose: The article is devoted to the study of egalitarian principles of medieval Czech statehood and the legal system. Methods: The authors pay special attention to the peculiarities of family self-government of the Czech communities, the institution of hazing in land law and the mechanism of reconciliation as an alternative to the death penalty. Findings: The paper proves that tribal remnants of the customary law of the ancient Czech people in the medieval era contributed to the preservation of egalitarian democratic principles of public administration and justice

Online Education after the Pandemic: Student Problems and Opportunities Research Using Big Data Tools

This paper presents a scientifically based approach to analyzing large volumes of data from digital traces of students on social networks, which allows you to effectively identify emerging and most discussed problems among students, as well as highlight pain points that provide opportunities for growth, development of universities and improvement of the characteristics of the educational process, support for students etc. The study is based on a thematic analysis of messages published in university communities on the VKontakte social network using big data tools. The study results showed that Russian university students still face a number of challenges, including weak technical infrastructure at universities, a digital divide in access to online education, and negative attitudes towards distance learning.The scientific problem of the study is the contradiction between the existing volume of unstructured data of students’ digital traces in social networks and the lack of a scientifically-based and proven methodological approach to the analysis and evaluation of this voluminous data, which creates obstacles to fundamental research into the relationship between students’ activity in social networks and their satisfaction quality of the educational process. The practical focus is determined in conducting data analysis using big data tools. The findings and evidence-based implications are useful for developing innovative strategies and tools for assessing and supporting students.The results show that the use of big data tools for tracking trends based on digital traces of students on social networks provides highly accurate analytical data and can become the basis for identifying problematic situations in individual universities and the industry as a whole, for data-driven decision-making and management

Dynamics of Students’ Opinions in the Context of the Transition to Online Learning Based on Social Network Data

The article presents the results of the analysis of users’ sentiment in social networks, performed using big data tools. The research was aimed at developing the methodology, which enables to analyze the content of social networks, assess students’ attitude to the transition to online learning in conditions of COVID-19 pandemic, identify dynamics and main trends in student satisfaction with the quality of educational process. We explored about 2 million posts and comments posted in university social networks (more than 1000 university public pages) for the period from Sept 2020 to July 2021. Special attention was paid to the problems of communication between students and teachers, strategies to solve them, an emotional reaction. PolyAnalyst software was applied for data precleaning. It has been found that the main problem affecting the quality of education is a change in the mechanisms of interaction between students and teachers. Based on student publications in social networks, we have identified the strategies for adapting students to online learning. We came to a conclusion that teachers’ support of students is crucial in preventing and solving social and academic problems in conditions of online learning. One of the ways to improve interaction between students and teachers, raise students’ involvement is using discussion forums, chats in messengers for academic purposes, and providing teachers’ methodical support

New advances in Raman study of polyvinylchloride structure

In this work we investigated Raman spectra of a number of industrial grades of polyvinylchloride powder and films, prepared from solutions in tetrahydrofuran and acetophenone. The number and spectral characteristics of the Raman lines in the spectral regions of the C-Cl stretching vibrations and in the region of the C-H and CH2 stretching vibrations were evaluated

Digital footprint in predicting school graduates’ educational strategy

This research article aims at evaluating the results of the school graduates’ educational strategy transformation with the help of digital footprint data. The analysis of official and unofficial Internet communities of universities in the social network «VKontakte» shows that their active users are school graduates, who thus receive the necessary information about the university. The method presented can become a promising tool to forecast the demand for higher education. The study covers the period from 2019 to 2021, a total of 502 thousand user profiles having been identified, 246 thousand accounts included in the final sample. The results show that during the analyzed period the number of user subscriptions to university communities has decreased in all Russian regions. The orientation towards universities located in other regions has also changed: these were more popular before the pandemic, being subscribed to by the majority of students, whereas after the spread of COVID-19, most of the graduates began to choose universities located in their native region. A significant limitation of this method is that a number of profiles are closed, which logically does not allow to use them in further analysis. The results of the study show, however, high validity and wide opportunities for the use of the digital footprint method when predicting young people’s educational trajectory and planning the enrollment campaign, both on the scale of the university and the whole country.В исследовательской статье с использованием данных цифровых следов оцениваются результаты трансформации образовательной стратегии учащихся 11-х классов средней школы. Анализ официальных и неофициальных вузовских интернет-сообществ в социальной сети «ВКонтакте» показал, что их активными пользователями являются выпускники школ, которые таким образом получают необходимую информацию о высшем учебном заведении. Представленный в статье метод использования цифровых следов может стать перспективным инструментом прогнозирования спроса на высшее образование. Проведенное исследование охватило период с 2019 года по 2021 год, всего было идентифицировано 502 тысячи профилей пользователей, в финальную выборку попали 246 тысяч аккаунтов. Результаты показали, что за анализируемый период произошло сокращение числа подписок пользователей на вузовские сообщества. Данный процесс наблюдался во всех российских регионах. Также изменилась ориентация на вузы, расположенные в других регионах. Если до пандемии большинство учащихся подписывалось на сообщества вузов, находящихся в другом регионе, то после нее большая часть выпускников стала выбирать вузы родного региона. Существенным ограничением метода использования цифровых следов является то, что ряд профилей относится к закрытым, и это не позволяет использовать их в дальнейшем анализе. Тем не менее результаты исследования показали высокую валидность и широкие возможности использования метода цифровых следов в предсказании образовательной траектории молодежи и планировании приемной кампании в масштабах как вуза, так и страны в целом

Interrelations between viral load and cellular immunity in patients with COVID-19 of varying severity

Assessment of viral load levels in various biological samples taken from the respiratory tract can be an indicator of an ongoing process of active viral replication and may be used to monitor severe respiratory viral infections. The study of the relationship between SARS-CoV-2 viral load and immunological laboratory parameters is an important step in the search for clinical markers of COVID-19.The aim of this research was to quantify viral load in patients with COVID-19 and to identify the relation-ship between viral load and changes in the parameters of the cellular component of the immune system.A laboratory examination was carried out on 74 patients diagnosed with COVID-19, they were divided into 3 groups based on the severity of the disease: mild, moderate, severe. Total viral load in clinical samples was determined by the number of SARS-CoV-2 RNA copies per 100 copies of the reference RNaseP gene.     A comprehensive assessment of the cellular component of the immune system was performed using flow cytometry and direct monoclonal antibodies, and the IL-6, and C-reactive protein concentrations were determined.We revealed a relationship between the development of serious clinical conditions in the patients with COVID-19, and the levels of viral load. High levels of viral RNA in biological samples correlate with main indicators of the T cell component of the immune system associated with disease severity. In a subgroup of patients with an extremely high viral load, strong positive correlations were found between the relative numbers of cytotoxic lymphocytes (CD3+CD8+), activated T lymphocytes (CD3+HLA-DR+), as well as absolute and relative numbers of activated B lymphocytes and NK cells (CD3-CD25+).Laboratory monitoring of the cellular component of the immune system, along with the assessment of viral loads, should improve  early assessment of clinical condition in the patients with COVID-19. Changes   in expression levels of activation markers on immune cells can be potentially viewed as indicators of recovery during COVID-19

Клинический случай острого описторхоза в эндоскопической практике

A clinical case of one of the most common parasitic diseases in the Russian Federation, opisthorchiasis, is presented. Today, opisthorchiasis and its associated complications are an urgent problem in medicine. Parasitic invasions are in fourth place in terms of damage to public health. There is no specific clinical picture, and the predominance of latent forms makes it difficult to diagnose opisthorchiasis. Particular attention is paid to the issue of complications, the most significant of which are acute pancreatitis, purulent cholangitis, liver abscesses, perforation of the bile ducts with the development of bile peritonitis. In the chronic course of invasion, parasitism occurs in the host‘s hepatobiliary tract, production of toxic and immunogenic waste products, and disruption of cell metabolism, which is one of the factors contributing to the development of cancer of the bile ducts and pancreas. The relevance of the problem of opisthorchiasis and its complications, combined with the complex and vulnerable diagnosis of this disease (clinical, laboratory, instrumental), demonstrate the importance of finding effective methods for its detection.Представлен клинический случай одного из самых распространенных на территории Российской Федерации паразитарных заболеваний – описторхоза. На сегодняшний день описторхоз и ассоциированные с ним осложнения являются актуальной проблемой в медицине, так как глистные инвазии занимают четвертое место по ущербу здоровью населения. Отсутствие специфической клинической картины, а также преобладание латентных форм обусловливает трудности диагностики описторхоза. Особое внимание отводится вопросу осложнений, наиболее значимыми из которых являются острый панкреатит, гнойный холангит, абсцессы печени, перфорация желчных протоков с развитием желчного перитонита. При хроническом течении инвазии происходит паразитирование в гепатобилиарном тракте хозяина, продуцирование токсичных и иммуногенных продуктов жизнедеятельности, нарушение метаболизма клеток, что является одним из факторов, способствующих развитию рака желчных протоков и поджелудочной железы. Актуальность проблемы описторхоза и его осложнений, сочетающихся со сложной и уязвимой диагностикой данного заболевания (клинической, лабораторной, инструментальной), демонстрирует значимость поиска эффективных методов его выявления

Microvesicles produced by natural killer cells of the NK-92 cell line affect the phenotype and functions of endothelial cells of the EA.Hy926 cell line

Microvesicles (MVs) are small (100-1000 nm) subcellular structures produced by both motionless and activated cells that can transfer molecules to target cells, and regulate physiological and pathological processes. MVs of leukocyte origin, in particular those produced by natural killer cells (NK cells), remain the least studied population of MVs. NK cells can change the functional activity of endothelial cells (ECs) and are involved in regulating angiogenesis. The ability of NK cell-derived MVs to influence the functionality of ECs is understudied currently. We aimed to study the effect of MVs produced by NK cells of the NK-92 cell line on the phenotype, caspase activity, proliferation and migration of ECs of the EA.Hy926 cell line. We cultured ECs in the presence of MVs derived from the NK-92 cell line, and then used flow cytometry to assess changes in EC phenotype, intracellular protein transfer from MVs to ECs, and the relative death of ECs. We used western blot analysis to evaluate the expression of granzyme B in NK cells and in the MVs that they produced, as well as the expression of granzyme B, caspases, extracellular-regulated kinase (ERK) and protein kinase B (AKT) in ECs. We also assessed the proliferation and migration of ECs in the presence of MVs derived from cells of the NK-92 cell line. The results revealed significant differences in the proteomic profiles of cells of the NK-92 cell line and their MV product. Contact between ECs and MVs derived from cells of the NK-92 cell line is accompanied by the following events: a) expression of granzyme B in ECs, b) activation of caspase-9 and caspase-3, with partial EC death, c) appearance of the panleukocyte marker CD45 on ECs, d) decrease in CD105 expression, and increase in CD34 and CD54 expression, and e) inhibition of EC migration. Transfer of ERK (but not AKT) from MVs derived from cells of the NK-92 cell line to ECs, at a concentration 10 times lower than that which causes EC death, leads to an increase in EC proliferation