419 research outputs found

    Phenomena of stability of the coal seam roof with a yielding support

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    Purpose. Determining the conditions and parameters for ensuring the stability of the coal seam roof with a yielding support in the area adjacent to face and behind it under the influence of dynamic loads based on the analytical and laboratory studies. Methods. To achieve the purpose set, analytical studies have been carried out using the basic principles of the theory of elasticity and vibrations, the hypothesis of girders and the hinged-block displacement of the stratified rock stratum. Also, the laboratory studies of models from equivalent materials have been performed, in which the coal seam roof is presented in the form of a girder having a yielding support with variable rigidity from the filling material under dynamic load. Findings. As a result of performed studies, the phenomenon has been determined that the condition for the stability of the coal seam roof is a geometric parameter that reflects moving of the girder with a yielding support, under the force impact of a falling load with a known mass and the physical-geometrical characteristics of the deformable system. It has been determined that as a result of a change in the spans length, a change in the flexural rigidity of the girder occurs, which means that the yield influence of the same supports on the stability of the coal seam roof is different. The values have been set and the relationship has been studied of the physical-mechanical characteristics of the filling mass as a yielding support. Originality. It has been proven scientifically that the stress-strain state (SSS) of a system in which the coal seam roof is studied as a girder depends on the physical-geometrical characteristics of the system, as well as the type and place of applying the external load, in case when the law of the girder movement in time is determined. Practical implications. The effective supporting of the undermined rock stratum in the working part of the longwall face and behind the face is achieved by placing the yielding supports in the mined-out space or by using the backfill in the mined-out space while conducting the stope operations, thus, increasing the efficiency of measures to protect the labour of miners in coal mines.Мета. Визначення умов і параметрів забезпечення стійкості покрівлі пласта з податливою опорою у привибійному просторі та позаду очисного вибою під впливом динамічних навантажень на основі аналітичних і лабораторних досліджень. Методика. Для досягнення поставленої мети були виконані аналітичні дослідження із застосуванням основних положень теорії пружності й коливань, гіпотези балок і шарнірно-блокового зсування породної товщі, що розшаровується, а так само лабораторні дослідження моделей з еквівалентних матеріалів, в яких покрівля вугільного пласта представлена у вигляді балки, що має податливу опору змінної жорсткості із закладного матеріалу при динамічному навантаженні. Результати. В результаті виконаних досліджень визначено феномен, що умовою стійкості покрівлі вугільного пласта, є геометричний параметр, що відображає переміщення балки з піддатливою опорою, при силовому впливі падаючого вантажу відомої маси і фізико-геометричні характеристики деформованої системи. Визначено, що в результаті зміни довжини прольотів, відбувається зміна згинальної жорсткості балки, а значить вплив податливості одних і тих же опор, на стійкість покрівлі вугільного пласта різний. Встановлено величини і досліджено взаємозв’язок фізико-механічних характеристик закладного масиву як піддатливої опори. Наукова новизна. Науково доведено, що напружено-деформований стан системи, в якій покрівля вугільного пласта досліджується як балка, залежить від фізико-геометричних характеристик системи, виду і місця докладання зовнішнього навантаження, коли визначено закон руху балки в часі. Практична значимість. Ефективне підтримання підробленої породної товщі в робочій частині лави і позаду очисного забою, досягається за рахунок розміщення у виробленому просторі піддатливих опор або застосування закладки виробленого простору при веденні очисних робіт, що так само підвищує ефективність заходів з охорони праці гірників у вугільних шахтах.Цель. Определение условий и параметров обеспечения устойчивости кровли пласта с податливой опорой в призабойном пространстве и позади очистного забоя под воздействием динамических нагрузок на основе аналитических и лабораторных исследований. Методика. Для достижения поставленной цели были выполнены аналитические исследования с применением основных положений теории упругости и колебаний, гипотезы балок и шарнирно-блокового сдвижения расслоившейся породной толщи, а также лабораторные исследования моделей из эквивалентных материалов, в которых кровля угольного пласта представлена в виде балки, имеющей податливую опору переменной жесткости из закладочного материала при динамической нагрузке. Результаты. В результате выполненных исследований определен феномен, что условием устойчивости кровли угольного пласта является геометрический параметр, отражающий перемещение балки с податливой опорой, при силовом воздействии падающего груза известной массы и физико-геометрические характеристики деформируемой системы. Определено, что в результате изменения длины пролетов, происходит изменение изгибной жесткости балки, а значит влияние податливости одних и тех же опор, на устойчивость кровли угольного пласта различно. Установлены величины и исследована взаимосвязь физико-механических характеристик закладочного массива как податливой опоры. Научная новизна. Научно доказано, что напряженно-деформированное состояние системы, в которой кровля угольного пласта исследуется как балка, зависит от физико- геометрических характеристик системы, вида и места приложения внешней нагрузки, когда определен закон движения балки во времени. Практическая значимость. Эффективное поддержание подработанной породной толщи в рабочей части лавы и позади очистного забоя, достигается за счет размещения в выработанном пространстве податливых опор или применения закладки выработанного пространства при ведении очистных работ, что так же повышает эффективность мероприятий по охране труда горнорабочих в угольных шахтах.The authors express their gratitude to the staff of the Mining Department of Donetsk National Technical University and Krasnoarmiisk (Pokrovsk) Industrial Institute for assistance in conducting the laboratory research

    SCORE performance in Central and Eastern Europe and former Soviet Union: MONICA and HAPIEE results

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    Aims: The Systematic COronary Risk Evaluation (SCORE) scale assesses 10 year risk of fatal atherosclerotic cardiovascular disease (CVD), based on conventional risk factors. The high-risk SCORE version is recommended for Central and Eastern Europe and former Soviet Union (CEE/FSU), but its performance has never been systematically assessed in the region. We evaluated SCORE performance in two sets of population-based CEE/FSU cohorts. Methods and results: The cohorts based on the World Health Organization MONitoring of trends and determinants in CArdiovascular disease (MONICA) surveys in the Czech Republic, Poland (Warsaw and Tarnobrzeg), Lithuania (Kaunas), and Russia (Novosibirsk) were followed from the mid-1980s. The Health, Alcohol, and Psychosocial factors in Eastern Europe (HAPIEE) study follows Czech, Polish (Krakow), and Russian (Novosibirsk) cohorts from 2002–05. In Cox regression analyses, the high-risk SCORE ≥5% at baseline significantly predicted CVD mortality in both MONICA [n = 15 027; hazard ratios (HR), 1.7–6.3] and HAPIEE (n = 20 517; HR, 2.6–10.5) samples. While SCORE calibration was good in most MONICA samples (predicted and observed mortality were close), the risk was underestimated in Russia. In HAPIEE, the high-risk SCORE overpredicted the estimated 10 year mortality for Czech and Polish samples and adequately predicted it for Russia. SCORE discrimination was satisfactory in both MONICA and HAPIEE. Conclusion: The high-risk SCORE underestimated the fatal CVD risk in Russian MONICA but performed well in most MONICA samples and Russian HAPIEE. This SCORE version might overestimate the risk in contemporary Czech and Polish populations

    A ROLE OF ARTISTIC ADVANCE-GUARD IS IN A WORLD CULTURE. PROBLEMS OF TEACHING IN THE COURSE OF CULTURAL STUDIES

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    The theoretical and practical questions of teaching of culture are examined in the article. Interrelation of elite and mass culture, place of art of advance-guard, is in world civilization. The article describes the peculiarity of the interaction of multilevel layers of artistic culture in a certain segment of the modern history of the first decades of the twentieth century

    THE CONCEPT OF MORALITY IN MODERN EDUCATION

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    The article deals with problems of formation of highly moral person in the course of edu-cational activity.the question is raised about the necessity and methods of forming a panoramic style of pedagogical thinking, which is one of the factors in the formation of the educational envi-ronment. It talks about the axiological meaning of education.The article deals with problems of formation of highly moral person in the course of edu-cational activity.the question is raised about the necessity and methods of forming a panoramic style of pedagogical thinking, which is one of the factors in the formation of the educational envi-ronment. It talks about the axiological meaning of education

    Влияние функциональной взаимосвязи понятия, образа и действия на процесс решения междисциплинарных технологически ориентированных задач

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    This article studies the influence of the methods used by students to solve tasks on the effectiveness of the learning process based on their analysis. The study has revealed that mastering the combined method based on the functional relationship between concept, image and action in the process of solving interdisciplinary technological tasks is one of the mechanisms of effective preparation of students for professional activity in the labour market of related professions.En este artículo, basado en un análisis de los métodos utilizados por los estudiantes para resolver problemas, se investiga su influencia en la efectividad del proceso de aprendizaje. En el curso del estudio, se reveló que el dominio del método combinado, basado en la relación funcional del concepto, la imagen y la acción, en el proceso de resolución de problemas tecnológicos interdisciplinarios es uno de los mecanismos para la preparación efectiva de los estudiantes para actividades profesionales en el contexto de la aparición de profesiones relacionadas en el mercado laboral.В данной статье на основе анализа используемых обучающимися способов решения задач исследуется их влияние на результативность процесса обучения. В процессе исследования выявлено, что владение комбинированным способом, основанном на функциональной взаимосвязи понятия, образа и действия, в процессе решения междисциплинарных технологических задач выступает одним из механизмов эффективной подготовки обучающихся к профессиональной деятельности в условиях появления на рынке труда смежных профессий

    Xenobiotic-induced activation of human aryl hydrocarbon receptor target genes in Drosophila is mediated by the epigenetic chromatin modifiers

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    Aryl hydrocarbon receptor (AHR) is the key transcription factor that controls animal development and various adaptive processes. The AHR\u27s target genes are involved in biodegradation of endogenous and exogenous toxins, regulation of immune response, organogenesis, and neurogenesis. Ligand binding is important for the activation of the AHR signaling pathway. Invertebrate AHR homologs are activated by endogenous ligands whereas vertebrate AHR can be activated by both endogenous and exogenous ligands (xenobiotics). Several studies using mammalian cultured cells have demonstrated that transcription of the AHR target genes can be activated by exogenous AHR ligands, but little is known about the effects of AHR in a living organism. Here, we examined the effects of human AHR and its ligands using transgenic Drosophila lines with an inducible human AhR gene. We found that exogenous AHR ligands can increase as well as decrease the transcription levels of the AHR target genes, including genes that control proliferation, motility, polarization, and programmed cell death. This suggests that AHR activation may affect the expression of gene networks that could be critical for cancer progression and metastasis. Importantly, we found that AHR target genes are also controlled by the enzymes that modify chromatin structure, in particular components of the epigenetic Polycomb Repressive complexes 1 and 2. Since exogenous AHR ligands (alternatively - xenobiotics) and small molecule inhibitors of epigenetic modifiers are often used as pharmaceutical anticancer drugs, our findings may have significant implications in designing new combinations of therapeutic treatments for oncological diseases. © Akishina et al

    Development of methodology for controlling the parameters of TP

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    © Published under licence by IOP Publishing Ltd. This article describes TP control step of the intelligent system for predicting the properties of CGI, which includes three parts: the selection of parameters for comparison, the comparison with the simulation results, the change of the current TP. The list of parameters under which control in the production is carried out has been determined, the adjustment algorithm of TP is designed

    Glycopeptide antibiotics: structural and functional aspects, human medicinal use, and standardisation

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    In recent years, glycopeptide antibiotics have been widely used to treat severe bacterial infections. The long-term use of first-generation antibiotics of this group (vancomycin, teicoplanin) has contributed to the emergence of bacteria resistant to them. The problem of resistance has motivated the development of three new glycopeptide antibiotics: dalbavancin, telavancin, and oritavancin. The aim of this study was to consolidate and analyse the data from literature and current quality standards related to glycopeptide antibiotics. The article presents basic information about the discovery of glycopeptide antibiotics of natural origin (vancomycin, teicoplanin) and their derivatives (telavancin, oritavancin, dalbavancin). It briefly characterises the structures of the glycopeptide antibiotics under consideration and describes their main properties, application, and distribution in the pharmaceutical market. The article also gives information on the spectra of antibacterial activity of vancomycin, teicoplanin, and their semi-synthetic derivatives. It considers approaches to vancomycin and teicoplanin standardisation and covers the main requirements of leading pharmacopoeias for the quality of vancomycin, teicoplanin, and the corresponding medicinal products. According to the study results, glycopeptide antibiotics are still widely prescribed because of their high effectiveness in diseases caused by Gram-positive bacteria. However, at present, leading pharmacopoeias have developed and implemented quality standards only for two antibiotics of the group: vancomycin and teicoplanin. According to the results of literature consolidation, further modification of glycopeptide antibiotics is aimed at creating compounds characterised by prolonged action and greater effectiveness against pathogenic microorganisms. Thus, the attention of researchers should be directed to further standardisation of the newest derivatives of glycopeptide antibiotics: telavancin, oritavancin, and dalbavancin

    Правосубъектность ребенка: актуализация возможностей и их ограничения

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    The subject of this research is the concept of a child’s legal capacity in an interdisciplinary context and the validity of various approaches for determining the essence and scope of a child’s legal capacity in terms of Russian public and private legislation and to provide suggestions for improvement.Methodology: The authors’ general research methods for cognition are: analysis, synthesis, and abstraction. This research is also based on legal acts and judicial practice, as well as on the opinions of scientists.Results: On the one hand, differentiations in terms of the essence, structure and scope of a child’s legal capacity within the branches of Russian law are justified according to the specifics of their subject and methods of legal regulation. On the other hand, the differences in approaches presented in them, especially according to age criterion, are far from universally justified, and this is especially characteristic of the active component of legal personality – or legal capacity. Thus, 14 and 16 are the ages of legal capacity in terms of constitutional law; 6, 14 and 16 for civil law; 14, 15 and 16 for labour law; 15 for medical law; 10, 14, 15, 16 for family law; etc. The law on education does not indicate any age benchmarks, being oriented towards the school education periods. At the same time, the lower boundaries of ‘minimal legal capacity’ are established only for the sake of civil legal relations and administrative and criminal liability. In other cases, in the assessment of a child’s ability to make legally significant decisions, the law enforcement officer considers a child’s individual psychological characteristics. Typically this approach proves to be correct. Psychological data indicate the development of an acceptable level of cognitive ability by the age of 12; therefore, the formally enshrined concept of child consent to certain legally significant acts beginning at the age of 10 requires discussion and possible adjustment. The ages of 14 and 16 as starting points for basic elements of the legal capacity (legal personality) are reasonable and must be applied systematically; other intermediate solutions are not justified. In terms of a generally correct decision with regard to the moment when the age of legal capacity begins, it would be reasonable to correlate this with the protection of a child’s interests before his/her birth. There is no unified approach to understanding a child’s ability to perform legal duties: in civil law such ability is denied, while in other legal spheres it exists. As for family law, it should be assimilated into the general group. Conclusions: the concept of a child’s legal capacity requires systematization and enhancement as a prerequisite for a reasonable and justified arrangement of children's world – both within the family and in the public sphere.Исследуются актуальные правовые аспекты содержания правосубъектности ребенка различных возрастных категорий, прежде всего его дееспособности, относительно сущности и дифференциации объема которой имеются далеко не всегда обоснованные различия в отраслях российского законодательства – частных и публичных. Анализируется значение нормативно-правовых предписаний об охране его интересов до рождения. На основе обобщения норм различных отраслей российского и зарубежного законодательства, наделяющих ребенка определенными юридическими обязанностями, выявляется необходимость включения данной конструкции и в семейное законодательство. Выводы подкрепляются данными психологической доктрины об особенностях развития ребенка в зависимости от возраста и иных факторов
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