642 research outputs found

    Обнаружение частичных разрядов импульсным методом

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    Выпускная квалификационная работа содержит 124 с., 68 рис., 13 табл., 22 источника, 1 прил. Ключевые слова: импульсный метод, частичный разряд, обнаружение, дефект, науглероживание. Объекты исследования: секции конденсатора (90 пФ, 0,12 мкФ, 700 пФ, 1100 пФ, 1500 пФ), пропитывающий состав (касторовое масло). Цель работы: исследование метода для обнаружения частичных разрядов при помощи подаваемого импульсного напряжения на испытуемый объект. Проведено испытания по обнаружения частичных разрядов путем подачи импульса с крутым фронтом на испытуемый объект, в котором возможно появление частичных разрядов (секция импульсного конденсатора). Установлено, что появление частичных разрядов изменяет форму тока через испытуемый объект путем подачи на объект напряжения с крутым фронтом. Различная емкоIn the production, transportation and processing of biological resources different electrical equipment is used, the integral part of which are DC machines. Energy efficiency and reliability of the production depends on the drives. The breakdown even of one engine may stop the production process and consequently entail losses. One reason for the failure of the DC motors is insulation damage due to exposure to partial discharge, however, a partial discharge detection technique has not been developed yet. For early warning of failure of DC machines and reducing the cost of unplanned stoppage on the replacement of a failed motor it is proposed to detect partial discharge sat an early stage. There are many developments related to the detection of partial discharges. The majority of methods re

    Организация строительного контроля при реализации инвестиционных проектов ПАО «Газпром» на примере магистрального газопровода «Сила Сибири»

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    Объектом исследования является строительство магистрального газопровода «Сила Сибири». Цель работы – разработать процесс организации строительного контроля на основе реализованных проектов ПАО «Газпром» и осуществить проведение строительного контроля при строительстве магистрального газопровода «Сила Сибири». В процессе исследования проводились анализ литературных источников, рассмотрение и анализ различных схем организации строительного контроля. В результате исследования была разработана модель и схема организации строительного контроля, рассчитаны оптимальные параметры проведения строительного контроля, разработаны мероприятия по охране труда и промышленной безопасности, охране окружающей среды. Степень внедрения: внедрена с 2015 года. Область применения: объекты ПАО «Газпром».The object of study is the construction of the gas pipeline "Power of Siberia". Purpose – to develop a process of organization building control on the basis of the completed projects of PJSC "Gazprom" and carry out the construction control during the construction of the gas pipeline "Power of Siberia". In the process of investigation the analysis of literature sources, review and analysis of various schemes of the organization of building control. In the result of the study a model was developed and diagram of building control, the calculated optimal parameters for building control, measures on labor protection and industrial safety, environmental protection. Level of implementation: implemented in 2015. Scope: the objects of PJSC "Gazprom"

    C-Peptide and Atherogenesis: C-Peptide as a Mediator of Lesion Development in Patients with Type 2 Diabetes Mellitus?

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    Patients with insulin resistance and early type 2 diabetes exhibit an increased propensity to develop a diffuse and extensive pattern of arteriosclerosis. Typically, these patients show increased levels of C-peptide and over the last years various groups examined the effect of C-peptide in vascular cells as well as its potential role in lesion development. While some studies demonstrated beneficial effects of C-peptide, for example, by showing an inhibition of smooth muscle cell proliferation, others suggested proatherogenic mechanisms in patients with type 2 diabetes. Among them, C-peptide may facilitate the recruitment of inflammatory cells into early lesions and promote lesion progression by inducing smooth muscle cell proliferation. The following review will summarize the effects of C-peptide in vascular cells and discuss the potential role of C-peptide in atherogenesis in patients with type 2 diabetes

    Cardiovascular protection in type 2 diabetes:Insights from recent outcome trials

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    This review examines recent randomized controlled cardiovascular (CV) outcome trials of glucose-lowering therapies in type 2 diabetes and their impact on the treatment of patients with type 2 diabetes. The trials were designed to comply with regulatory requirements to confirm that major adverse cardiac events (MACE) are not detrimentally affected by such therapies. Trials involving dipeptidyl peptidase-4 (DPP-4) inhibitors did not alter a composite MACE outcome comprising CV deaths, non-fatal myocardial infarction and non-fatal stroke; however, the possibility that some members of this class might incur a small increased risk or worsening of heart failure cannot be excluded. Some studies on glucagon-like peptide-1 receptor agonists (liraglutide: LEADER trial; semaglutide: SUSTAIN-6 trial) found significant benefits for MACE, while treatment with sodium-glucose co-transporter-2 inhibitors (empagliflozin: EMPA-REG OUTCOME trial; canagliflozin: CANVAS trial) also significantly reduced MACE and reduced hospitalization for heart failure. Comparisons among trials are complicated by variance in the populations recruited, particularly CV status at randomization, and differences in trial design, data collection and analyses. A large proportion of patients recruited into these trials have previously experienced adverse CV events; thus, the therapies are mostly assessing secondary prevention of a further event. This contrasts with the overall type 2 diabetes population receiving glucose-lowering therapies, of whom the majority will not have had MACE and will be regarded as primary prevention. Overall, the trials provide reassuring evidence that new glucose-lowering medications do not adversely affect CV events and some of these agents may offer CV protection

    Anticoagulant and Antiplatelet Therapy in Patients with Atrial Fibrillation and Coronary Artery Disease

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    Anticoagulation represents the mainstay of therapy for most patients with atrial fibrillation. Patients on oral anticoagulation often require concomitant antiplatelet therapy, mostly because of coronary artery disease. After coronary stent implantation, dual antiplatelet therapy is necessary. However, the combination of oral anticoagulation and antiplatelet therapy increases the bleeding risk. Risk scores such as the CHA2DS2-Vasc score and the HAS-BLED score help to identify both bleeding and stroke risk in individual patients. The guidelines of the European Society of Cardiology provide a rather detailed recommendation for patients on oral anticoagulation after coronary stent implantation. However, robust evidence is lacking for some of the recommendations, and especially for new oral anticoagulants and new antiplatelets few or no data are available. This review addresses some of the critical points of the guidelines and discusses potential advantages of new anticoagulants in patients with atrial fibrillation after stent implantation

    Production de litières par des forêts situées dans le pré-delta du fleuve Paraná (Argentine)

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    • The objectives of this study were to measure litterfall production of the four floodplain forest types and to analyze the relationship between litterfall (forest type, dominant species, organic fractions) and flood pulses. • Litterfall production was measured in two mono-specific stands of Salix humboldtiana or Tessaria integrifolia, respectively, and two mixed forests dominated by A. inundata or Nectandra angustifolia, during 1998 and the 2000–2002 periods. • Mono-specific stands presented similar productivities (6.8 and 6.5 Mg dry matter ha−1 y−1, respectively), but differed significantly from the two other. The highest litterfall production was obtained during the large flood that occurred during 1998, decreasing later throughout the study period. Leaves were the dominant fraction of litterfall, followed by branches, flowers and fruits. • Only S. humboldtiana, T. integrifolia and A. inundata forests showed distinct patterns of litterfall production, depending on the flooding pulse. N. angustifolia did not show a distinctive litterfall pattern • The forests studied here presented patterns of litter production associated with the flood pulse according to its location along a topographic gradient, that controls the litter productivity of these forests.• Cette étude avait pour but de mesurer la production de litière dans quatre forêts alluviales et d’analyser les relations entre les litières (selon le type de forêt, l’espèce dominante, et des fractions organiques) et les crues du fleuve Paraná (Argentine). • La production de litière a été mesurée dans deux forêts monospécifiques de Salix humboldtiana ou de Tessaria integrifolia, et dans deux forêts mixtes où l’espèce prédominante était soit Albizia inundata soit Nectandra angustifolia. Cette étude a été menée en 1998 puis de 2000 à 2002. • Les forêts monospécifiques présentent des productions de litières similaires (6.8 et 6.5 Mg matière sèche ha−1 ans−1 respectivement) et étaient significativement différentes des deux forêts mixtes. La plus forte production de litière a été obtenue au cours de la grande crue de 1998, puis a diminué progressivement au cours du temps. Les feuilles représentaient la principale fraction des litières, tandis que les branches, les fleurs et les fruits constituent des fractions mineures. • Les forêts dominées par S. humboldtiana, T. integrifolia et A. inundata ont vu leur production de litière évoluer en fonction des crues du fleuve Parana. Ce type de relation entre crue et production de litière n’a pas été détecté dans le cas des forêts de N. angustifolia. • Il existe ainsi une relation entre la production de litière et la hauteur des crues, elle-même conditionnée par un gradient topographique, qui détermine donc la production de litière de ces forêts.We are grateful to R. D’Angelo, R. Zanello, and O. Bejarano for their help in field data collection; and to “National Parks Administration (APN)” for allowing this study. Recognitions to the anonymous reviewers which helped to improve the original manuscript. This research has been partially funded by the PICT-ANPCyT 11928, the PIP-CONICET 6374, and the PID-UNER 2089/01.Peer reviewe

    Proof of Concept: Measuring Aortic Annulus Resistance by Means of Pressure-Volume Curves During Balloon Inflation to Guide Transcatheter Aortic Valve Implantation

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    This study assessed the basic working principle to measure aortic annulus resistance during balloon inflation for transcatheter aortic valve implantation (TAVI), by acquisition of pressure-volume curve for a guided semi-automatic implantation. A modular bench-system was used which allows the incremental inflation of valvuloplasty balloons by means of a stepper-motor driven linear axis with simultaneous recording of the pressure changes inside the system. Different porcine aortic xenografts were assessed by use of a non-compliant valvuloplasty balloon. In a second step transcatheter aortic stents were implanted inside target sized xenografts. The recorded pressure volume-curves showed that the system can accurately differentiate between different xenografts and assess the quality of the tissue rendering real-time analysis of pressure-volume curves during balloon-inflation possible, which has the potential to optimize the implantation procedure by direct adaptation to the patient specific anatomy and characteristics. Further investigations and development are warranted

    Отымённые глагольные дериваты как обозначения родства и свойства́ в немецком языке

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    В статье рассматриваются лексические единицы в классе немецкого глагола, образованные от обозначений родства и свойства́ преимущественно по конфиксальной модели ver + основа + t. Их главными особенностями следует признать нейтральную окрашенность, использование в качестве предикативов и в дословном значении зачастую вопреки созвучию с единицами других словарных множеств
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