Модификация эпидемиологической модели для прогнозирования развития социально-значимой инфекции (на примере хронического вирусного гепатита С)

Purpose of the study: to develop, evaluate the effectiveness and applicability of an epidemiological model for the development of chronic viral hepatitis C, with the ability to predict the number of people who need to be tested for the presence of the virus.Materials and methods. In our study, we used official data for the Republic of Bashkortostan on the spread of chronic viral hepatitis C (annual dynamics of cases) in the period from 2005 to 2020, which were provided at our request by the Republican Clinical Infectious Diseases Hospital. Demographic indicators for births and deaths were taken from the annual statistical report of Bashkortostanstat. The study considered 2 mathematical models: 1) Model SIR considers three groups: susceptible (those who have not yet become infected), infected and dropouts (those who have recovered or died). 2) The STIRD model is the SIR model, improved by the author, which takes into account five population groups: susceptible (those who have not yet become infected), tested (those who have been in contact with the infected people and require a test to clarify the diagnosis), infected, dropouts (those who recovered) and deceased.Results: from 2015 to 2017, the model provided representative data on the forecast of the infected people, the error was about 1.5-4%, but after this period, starting from 2018, the error rate became critical and the model lost its representativeness. To explain this phenomenon, there are 2 reasons: the first is the easy availability of drugs for the treatment of chronic hepatitis C, the second is the need to use Markov models in the model, since the calculation does not take into account the dynamics of changes in the coefficients of the model. As a result of the coronavirus pandemic in 2020, the error was more than 166%, this is due to a decrease in contacts between people and, as a result, a sharp decrease in the incidence of chronic hepatitis C.Conclusion. The complete epidemiological STIRD model proposed by the author (taking into account the demographic change in the structure of the population) has shown itself well in medium-term forecasting up to three years. A significant advantage of this model specification compared to other epidemiological models is the ability to predict the number of diagnostic laboratory tests needed to detect a virus in humans. This is important, since the diagnosis and treatment of chronic hepatitis C is covered from compulsory medical insurance and regional budgets. Epidemiological modeling opens up great opportunities for developing scenarios for combating viral hepatitis C, especially with its chronic form, because, according to WHO, each country has the opportunity to completely get rid of this socially significant infection by 2030.Целью данного исследования является разработка, оценка эффективности и применимости эпидемиологической модели развития хронического вирусного гепатита С, с возможностью прогнозирования количества человек, которым необходимо провести тестирование на наличие вируса.Материалы и методы. В своем исследовании были использованы официальные данные по Республике Башкортостан по распространению хронического вирусного гепатита С (ежегодная динамика заболевших) в период с 2005 по 2020 гг., которые были предоставлены по запросу к Республиканской клинической инфекционной больнице. Демографические показатели по рождаемости и смертности были взяты из ежегодного статистического отчета Башкортостанстата. В исследовании были рассмотрены 2 математические модели: 1) Модель SIR. Рассматривает три группы: восприимчивые (те, кто еще не заразился), инфицированные и выбывшие (те, кто выздоровел или умер). 2) Модель STIRD – усовершенствованная автором модель SIR, которая учитывает пять групп населения: восприимчивые (те, кто еще не заразился), тестируемые (те, кто контактировал с инфицируемыми и требующие проведения теста для уточнения диагноза), инфицированные, выбывшие (те, кто выздоровел) и умершие.Результаты. С 2015 до 2017 года модель давала репрезентативные данные по прогнозу инфицированных, ошибка составляла около 1,5–4%, но после этого периода, начиная с 2018г., процент ошибки стал критичным и модель потеряла свою репрезентативность. Чтобы объяснить это явление, есть 2 причины: первое, это легкодоступность препаратов для лечения ХВГС, второе, в модели необходимо использовать марковские модели, так как при расчете не учитывается динамика изменения коэффициентов модели. В итоге, в результате коронавирусной пандемии в 2020 году ошибка составила более 166%, это связано со снижением контактов между людьми и как результатом, резким снижением заболеваемости ХВГС.Заключение. Предложенная автором полная (с учетом демографического изменения структуры населения) эпидемиологическая модель STIRD хорошо себя показала при среднесрочном прогнозировании до трех лет. Существенным преимуществом данной спецификации модели по сравнению с другими эпидемиологическими моделями является наличие возможности построить прогноз по количеству необходимых для проведения диагностических лабораторных тестов на выявление вируса у человека. Это важно, так как диагностирование и лечение ХГВС покрывается из средств ОМС и региональных бюджетов. Эпидемиологическое моделирование открывает широкие возможности для разработки сценариев борьбы с вирусным гепатитом С, особенно с его хронической формой, ведь по данным ВОЗ у каждой страны есть возможность к 2030 г. полностью избавиться от данной социально-значимой инфекции

Bottom topography, length, chamber structure of timergazin canyon-like valley and problems of oil and gas exploration in basement

In this article there are specified: a sub-latitudinal valley bottom topography of South Tatar arch, valley length and a position of directive pallial-crustal first order fracture. The valley bottom chamber was considered as continental rift structure with fracture-block tectonics in plan. The possible contribution of the valley to hydrocarbon transit from deep formations is estimated. The Subkhankulovsky swell is specified as possible hydrocarbon deposit within the basement. © 2009

Using E-Learning Tools to Enhance Students- Mathematicians’ Competences in the Context of International Academic Mobility Programmes

Introduction. The article is concerned with the use of special electronic teaching tools to increase the students’ understanding of the subject and adaptation to the professional language environment of the host country, taking into account the mathematical education. Our purpose is to develop a methodology of multilingual support of mathematical courses in the host country to improve the effectiveness of students’ academic mobility using e-learning tools. Materials and Methods. The basis of the research was methods of system analysis and descriptive and analytical methods, primarily experimental. To identify advantages of the proposed approach the methods of empirical research were used (observation and comparison). To prove the efficiency, classical methods of measurement were used. Results. We analyzed the existing electronic learning environments and defined an e-learning environment Math-Bridge that allows for creating mathematical courses in several languages in parallel. For example, the e-training course “Optimization Methods” was developed in three languages for training Russian-speaking Master programme students. The comparative analysis of the target and control student’s groups showed that 100 % of the students in the target group achieved an excellent level of mastering competencies, while the control group has only 75 %. For the control group, the degree of motivation to mathematical studying has not virtually changed (increase by 0,86 %). In the target group the level of student interest to the mathematics increased from 0,9 % to 8,9 % (mean 2.21 %). Discussion and Conclusion. The results described in the article will be useful for the staff of international departments, administrations and deans, as well as teachers of those universities that participate in the students’ international academic mobility programmes

Экономическое бремя хронического вирусного гепатита С

Background. The spread of chronic viral hepatitis C (CVHC) among the population entails significant costs for society, both direct, associated with the treatment of such patients, and indirect, associated with the shortfall in fiscal payments to the budget, due to the disability of this category of patients. Therefore, an important task remains to assess the global economic burden of the disease, taking into account the pathological conditions of the human body associated with it.Objective: to systematize studies of published sources devoted to assessing the global economic burden of chronic viral hepatitis C.Material and methods. A feature of the proposed review design is paying attention not only to the objects of assessment under study, but also to the instrumental (including mathematical) means of scenario assessment of the global burden. The study analyzed 29 sources published between 2014 and 2020 and dedicated to assessing and forecasting the global economic burden of CVHC both in individual countries and continents as a whole, and in individual regions of countries. The main criterion for the selection of studies was the availability of an estimate of the global burden of CVHC, taking into account the use of direct antiviral drugs for the treatment of hepatitis C. The search was conducted in PubMed/MEDLINE and eLibrary databases, and in the ResearchGate network.Results. Of the 29 analyzed sources, 40% of the works consider the burden for CVHC only of certain genotypes; in the overwhelming number of articles (80%), when assessing the burden, the distribution of patients by the degree of liver fibrosis is taken into account. In 50% of the studies reviewed, quality of life adjustment tools (QALY or DALY) were used to estimate the global economic burden. A third of the publications took into account both the direct costs of treating CVHC and indirect costs, including those associated with a shortfall in the contribution to the gross national product due to temporary or permanent disability of this category of patients.Conclusion. The analysis showed that interest in assessing the global burden of CVHC began to appear in recent years, when expensive directacting antivirals for the treatment appeared. This is explained by the emergence of a question about the cost of implementing a scenario in which by a certain year it will be possible to completely exclude the spread of the disease. The results of this work may be useful in conducting such studies, including the determining of their design and the use of modern mathematical modeling tools.Актуальность. Распространение хронического вирусного гепатита С (ХВГС) среди населения влечет за собой значительные затраты для общества – как прямые, связанные с лечением, так и косвенные, связанные с недополучением фискальных платежей в бюджет из-за нетрудоспособности таких больных. Поэтому важной задачей остается оценка глобального экономического бремени заболевания с учетом ассоциированных с ним паталогических состояний организма человека.Цель: систематизация опубликованных исследований, посвященных оценке глобального экономического бремени хронического вирусного гепатита С.Материал и методы. Особенностью предложенного дизайна обзора является уделение внимания не только исследуемым объектам оценки, но и применяемым инструментальным (в т.ч. математическим) средствам сценарной оценки глобального бремени. Проведен анализ 29 источников, опубликованных в период с 2014 по 2020 гг. и посвященных оценке и прогнозу глобального экономического бремени ХВГС как в отдельных странах и на континентах в целом, так и в определенных регионах стран. Основным критерием отбора исследований было наличие оценки глобального бремени ХВГС с учетом использования для лечения гепатита С препаратов прямого противовирусного действия. Поиск осуществляли по базам PubMed/MEDLINE и eLibrary, а также в сети ResearchGate.Результаты. Из 29 проанализированных источников в 40% работ рассматривается бремя для ХГВС лишь определенных генотипов, в подавляющем количестве исследований (80%) при оценке бремени учитывается распределение больных по степени фиброза печени. В 50% рассмотренных публикаций использовались инструменты с поправкой бремени на качество жизни: QALY (англ. quality-adjusted life year) или DALY (англ. disability-adjusted life year). В 1/3 исследований учитывались как прямые издержки на лечение ХВГС, так и косвенные затраты, в т.ч. связанные с недополучением вклада в валовой национальный продукт за счет временной либо стойкой нетрудоспособности этой категории больных.Заключение. Анализ показал, что интерес к оценке глобального бремени ХВГС возник в последние годы, когда появились дорогостоящие препараты прямого противовирусного действия. Это объясняется возникновением вопроса о стоимости реализации сценария, при котором к определенному году полностью можно будет исключить распространение болезни. Результаты данной работы будут полезны в проведении подобных исследований, в т.ч. для определения их дизайна и применения современных инструментов математического моделирования

Bottom topography, length, chamber structure of timergazin canyon-like valley and problems of oil and gas exploration in basement

In this article there are specified: a sub-latitudinal valley bottom topography of South Tatar arch, valley length and a position of directive pallial-crustal first order fracture. The valley bottom chamber was considered as continental rift structure with fracture-block tectonics in plan. The possible contribution of the valley to hydrocarbon transit from deep formations is estimated. The Subkhankulovsky swell is specified as possible hydrocarbon deposit within the basement. © 2009

Bottom topography, length, chamber structure of timergazin canyon-like valley and problems of oil and gas exploration in basement

In this article there are specified: a sub-latitudinal valley bottom topography of South Tatar arch, valley length and a position of directive pallial-crustal first order fracture. The valley bottom chamber was considered as continental rift structure with fracture-block tectonics in plan. The possible contribution of the valley to hydrocarbon transit from deep formations is estimated. The Subkhankulovsky swell is specified as possible hydrocarbon deposit within the basement. © 2009

Bottom topography, length, chamber structure of timergazin canyon-like valley and problems of oil and gas exploration in basement

In this article there are specified: a sub-latitudinal valley bottom topography of South Tatar arch, valley length and a position of directive pallial-crustal first order fracture. The valley bottom chamber was considered as continental rift structure with fracture-block tectonics in plan. The possible contribution of the valley to hydrocarbon transit from deep formations is estimated. The Subkhankulovsky swell is specified as possible hydrocarbon deposit within the basement. © 2009

Sound localization and quantification analysis of an automotive engine cooling module

Sound emissions of an automotive engine cooling system are studied using both single-microphone directivity measurements and a rotating beamforming technique. These measurements provide reference acoustic data on such a system and some new understanding of the effect that the radiator induces on the distribution of sound sources. Indeed, the beamforming results indicate that, above the frequency limit allowed by the Rayleigh criterion, it is possible to localize and quantify the noise sources even through the heat-exchanger core. Moreover, for the investigated operating points along the fan performance curve, the sources are always distributed at the tip of the blades and, in particular, at the leading edge. The present evidence, confirmed by the similar trends of the frequency spectra with and without the heat exchanger, leads to the conclusion that the dominant sound mechanism is the turbulence-interaction noise. Nevertheless, this turbulence is produced within the gap between the fan ring and its casing rather than generated by the radiator core. The latter appears to induce negligible acoustic transmission losses but, more significantly, is found to have a minimal influence on the aerodynamic modification of sound sources for all the analyzed operating conditions.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Wind Energ