The resonance phenomenon in the reaction–diffusion systems

A new mechanism of pattern formation different from the Turing and oscillatory instabilities in the reaction–diffusion systems was found. It is closely connected with the resonance phenomenon that appears in the models when Jacobi's matrix of the kinetic part is equivalent to Jordan cell and diffusion coefficients are cited. Some results of numerical calculations of the blood coagulation model are discussed. The pattern formation regimes that can be treated as the results from the resonance phenomenon were observed

Magnetoresistance of p-GaAs/AlGaAs structures in the vicinity of metal-insulator transition: Effect of superconducting leads

Experimental and theoretical studies on transport in semiconductor samples with superconducting electrodes are reported. We focus on the samples close to metal-insulator transition. In metallic samples, a peak of negative magnetoresistance at fields lower than critical magnetic field of the leads was observed. This peak is attributed to restoration of a single-particle tunneling emerging with suppression of superconductivity. The experimental results allow us to estimate tunneling transparency of the boundary between superconductor and metal. In contrast, for the insulating samples no such a peak was observed. We explain this behavior as related to properties of transport through the contact between superconductor and hopping conductor. This effect can be used to discriminate between weak localization and strong localization regimes.Comment: 10 pages, 3 fi

ЛАБОРАТОРНИЙ СТЕНД КЕРУВАННЯ КРОКОВИМ ДВИГУНОМ ВІД SCADA СИСТЕМИ TRACE MODE

To improve the educational process in Zaporizhzhya National Technical University the laboratory bench of computer stepper motor control of SCADA TRACE MODE system through LPT or USB port of a personal computer is developed.The technique of laboratory work at the bench is done. The waveforms of current stepper motor are experimentally obtained.Для совершенствования учебного процесса в Запорожском национальном техничном университете разработан лабораторный стенд компьютерного управления шаговым двигателем от SCADA системы TRACEMODE через LPT и USB порты персонального компьютера. Разработана методика проведения лабораторных работ на стенде. Экспериментально получены временные диаграммы токов шагового двигателя ШД5Для вдосконалення навчального процесу у Запорізькому національному технічному університеті розроблено лабораторний стенд комп’ютерного керування кроковим двигуном від SCADA системи TRACE MODE через LPT та USB порти персонального комп’ютера. Розроблена методика проведення лабораторних робіт на стенді. Експериментально отримані часові діаграми струмів крокового двигуна ШД5

Substantive Interpretation of Machine Learning Solutions by the Example of Determining the Activity of the Tuberculosis Process in Individuals with Minimal Tuberculosis Residual Changes

In this article is described an application of various machine learning (ML) methods to obtain decision rules and its interpretation to a problem of recognition of activity of the tuberculosis process. The research data base included 489 patients registered in anti-tuberculosis institutions in Tyumen and Yekaterinburg. The conducted modeling by machine learning methods allowed to highlight 7 most informative features (the presence of calcifications, age, the content of leukocytes, hemoglobin, eosinophils, α2-fraction of globulins, γ-fraction of globulins) together with classification accuracy of 95% for both active and inactive patients. The research result may be interesting for medical specialists, data scientists and to all those interested in problems at the intersection of medicine and machine learning. © 2022 The authors and IOS Press

The Importance of High-Resolution Computed Tomography in the Early Diagnosis of Fibrotic Hypersensitivity Pneumonitis

Objective: to determine the high-resolution computed tomography (HRCT) signs and their combinations, suggesting the presence of fibrotic hypersensitivity pneumonitis (FHP).   Material and methods. The study included 52 patients with pathologically verified diagnosis of FHP who were examined according to the 2021 consensus criteria. All patients had lung HRCT no more than 4 months prior to lung biopsy. The analysis of the changes revealed during HRCT was carried out by qualitative and semi-quantitative methods. The presence of individual signs, the degree of their severity (as percentage relative to the volume of the entire lung tissue) and the features of distribution in the axial and longitudinal planes were taken into account. To search for significant combinations of HRCT signs, a correlation analysis was carried out.   Results. The most common HRCT signs in the examined group of FHP patients were reticular changes (96 %) and ground glass opacity (88 %). Most of the patients had signs that did not correspond to the picture of “typical FHP”, such as ground glass and emphysema. Relatively rare cases were centrilobular lesions (46.2 %) and mosaic attenuation (52 %), which are traditionally part of the “typical FHP” picture. In 22 cases (42.3 %) there were signs of emphysema, the presence of which significantly complicated the interpretation of HRCT data even in the cases of characteristic signs of FHP. Correlations of almost all HRCT signs were weak. The most common combinations of features were ground glass + reticular changes, emphysema + honeycombing, reticular changes + bronchiectasis. The combination of ground glass and reticular changes had a moderate correlation, but it has low specificity.   Conclusion. The HRCT picture of changes in the lungs among patients with a morphologically verified diagnosis of FHP has important features. A weak correlation between the signs does not allow to identify their combinations that can help in the early diagnosis of FHP with sufficient reliability

Impact of employment and unemployment levels on tuberculosis incidence and mortality rate in population

Introduction. The organization of countering the spread of tuberculosis, as a socially determined disease, remains relevant. Purpose. Assess the relationship between unemployment and employment rates with tuberculosis morbidity and mortality in Russia. Materials and methods. The analysis of the correlations of time series of values of tuberculosis morbidity and mortality rates, unemployment and employment rates of the population in the context of 85 constituent entities of Russia in the period of 2014–2020 years was carried out using the correlation coefficient with subsequent assessment of its reliability. Results and discussion. A reliable correlation was established between the studied socio‑economic factors and main indicators characterizing tuberculosis epidemic situation. Similar results have been obtained in a number of other studies.Введение. Организация противодействия распространению туберкулеза как социально обоснованного заболевания сохраняет свою актуальность. Цель исследования — оценить взаимосвязь уровней безработицы и занятости населения с заболеваемостью и смертностью от туберкулеза на территории России. Материалы и методы. Проведен анализ взаимосвязей динамических рядов значений показателей заболеваемости и смертности от туберкулеза, уровней безработицы и занятости населения в разрезе 85 субъектов России в период 2014–2020 гг. с применением коэффициента корреляции с последующей оценкой его достоверности. Результаты и обсуждение. Установлена достоверная корреляционная взаимосвязь между изучаемыми социально‑экономическими факторами и основными показателями, характеризующими эпидемическую ситуацию по туберкулезу. Аналогичные результаты получены в ряде других исследований

Kharkiv incoherent scatter facility

The structure, parameters and operating modes of the incoherent scatter radar of the Institute of Ionosphere, Kharkiv are presented. Some results of the ionosphere research obtained by this facility are shown.Наведено структуру, параметри і режими роботи радара некогерентного розсіяння Інституту іоносфери (м. Харків). Показано деякі результати спостережень іоносфери за допомогою цього обладнання

Dynamics of measles vaccination coverage in children’s multidisciplinary hospital of Yekaterinburg in 2017-2021

The purpose of the study is to assess the dynamics of measles vaccination coverage in children of the 1st year of life for 2017-2021 in Yekaterinburg.Цель исследования – оценка динамики охвата вакцинации корью детей 1-го года жизни за 2017-2021 гг. в г. Екатеринбурге

Identification and discussion of the main factors affecting fertility: the impact of the per capita monetary income indicator on the fertility rate of the population of the Russian Federation

The purpose of the study is to study and establish the nature of the relationship between the level of well-being of the population and the birth rate.Цель исследования – изучить и установить характер взаимосвязи между уровнем благосостояния населения и уровнем рождаемости