432 research outputs found

    Distributed automatic control of technological processes in conditions of weightlessness

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    Some problems associated with the automatic control of liquid metal and plasma systems under conditions of weightlessness are examined, with particular reference to the problem of stability of liquid equilibrium configurations. The theoretical fundamentals of automatic control of processes in electrically conducting continuous media are outlined, and means of using electromagnetic fields for simulating technological processes in a space environment are discussed

    The influence of non-vacuum electron-beam facing on the structure of Ti-Ta layers formed on the surface of VT1-0 alloy

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    The influence of electron-beam facing modes on the structure of Ti-Ta layers formed on the surface of commercially pure titanium VT1-0 has been studied in the paper. The mode of the electron-beam treatment of alloying powder mixture, by which there were no defects in the pad, has been identified. The methods of optical microscopy and scanning electron microscopy have shown that in pads there is dendritic segregation typical for the process of initial crystallisation. At greater magnifications it is possible to observe a structure of the laminar type. The X-ray phase analysis of titanium-tantalum layers justifies the presence of two phases: a hexagonal [alpha]'-phase and a cubic ([beta]-phase of titanium)

    Energy flow problem solution based on state estimation approaches and smart meter data

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    Accurate electric energy (EE) measurements and billing estimations in a power system necessitate the development of an energy flow distribution model. This paper summarizes the results of investigations on a new problem related to the determination of EE flow in a power system over time intervals ranging from minutes to years. The problem is referred to as the energy flow problem (EFP). Generally, the grid state and topology may fluctuate over time. An attempt to use instantaneous (not integral) power values obtained from telemetry to solve classical electrical engineering equations leads to significant modeling errors, particularly with topology changes. A promoted EFP model may be suitable in the presence of such topological and state changes. Herein, EE flows are determined using state estimation approaches based on direct EE measurement data in Watt-hours (Volt-ampere reactive-hours) provided by electricity meters. The EFP solution is essential for a broad set of applications, including meter data validation, zero unbalance EE billing, and nontechnical EE loss check. © 202

    An Improved Limit on Invisible Decays of Positronium

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    The results of a new search for positronium decays into invisible final states are reported. Convincing detection of this decay mode would be a strong evid ence for new physics beyond the Standard Model (SM): for example the existence of extra--dimensions, of milli-charged particles, of new light gauge bosons or of mirror particles. Mirror matter could be a relevant dark matter candidate. In this paper the setup and the results of a new experiment are presented. In a collected sample of about (6.31±0.28)×106(6.31\pm0.28) \times 10^6 orthopositronium decay s, no evidence for invisible decays in an energy window [0,80] keV was found and an upper limit on the branching ratio of orthopositronium \invdecay could be set: \binvdecay<4.2\times 10^{-7} (90% C.L.) Our results provide a limit on the photon mirror-photon mixing strength ϵ1.55×107\epsilon \leq 1.55\times 10^{-7} (90% C.L.) and rule out particles lighter than the electron mass with a fraction Qx3.4×105Q_x \leq 3.4 \times 10^{-5} of the electron charge. Furthermore, upper limits on the branching ratios for the decay of parapositronium Br(pPsinvisible)4.3×107Br(p-Ps\to invisible)\leq 4.3 \times 10^{-7} (90% C.L.) and the direct annihilation Br(e+einvisible)2.1×108Br(e^+e^-\to invisible)\leq 2.1 \times 10^{-8} (90% C.L.) could be set.Comment: 17 pages, 7 figures, added references, fixed limit on millicharged particles and changed two plots accordingl

    Identification of endophytic bactéria from micropropagated yacon (Smallanthus sonchifolius) crowing under autotrophic and Heterotrophic systems.

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    Yacon, Smallanthus sonchifolius, an Andean species. is a rich source of dictetíc oligofructans with low glucose content. proteins and phenolic compounds. These constituents have shown efficacy in the prevention of diet-related ehronic diseases, including gastroin-testinal disorders and diabetes |1,2|. Yacon is part of a research program at the National Center for Natural Products Research (NCNPR) and University of Mississippi Field Station to develop new alternative root crops for Mississippi while attempting to im-prove the diet of low incorne families. Yacon can be easily propa-gated by cultings. Virus and nematode infections have been re-ported on plants propagated by cuttings in Brazil. a country that hás adopted Yacon as specialty crop [3|. We have developed two culture systems. autotrophic and heterotrophic, to produce healthy plants. Herem we describe the presence of endophytic bactéria m micropropagated Yacon. In auxin free media, new roots were induced. Overa 15day period. the average root mduction per expiam was 5.45 to 8.75 under autotrophic and heterotrophic cul-tures, respectively. Root lenglh vaned between 3 and 60mrn. The presence of root hairs and lateral roots was noticed only in auto-trophic condilions. These beneficiai bactéria were identified and chemically ctiaracterized. Acknowledgement: This research work was partially supported by the USDA/ARS Cooperative Research Agreement No. 58-6408-2-009. Referentes; |1) Terada S. et ai. (2006] Yakugaku Zasshi 126(8): 665-669. (2| Valentová K. Ulri-chová j. (2003) Biomedical Papers 147: 119-130. [3| Mogor C. et ai, (2003) Acta Horticulturea 597: 311 -313

    INFLUENCE OF ANTIBODIES AGAINST CTLA-4 AND PD-1 UPON QUANTITIES OF THEIR TARGET RECEPTORS

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    Inhibitory receptors CTLA-4 and PD-1 (immune checkpoints) play a key role in regulation of immune reactions. They suppress excessive immune response against pathogenic microbes and prevent autoimmune reactions. The immune checkpoints are targets of the modern effective therapy based on human and humanized monoclonal antibodies (ipilimumab and nivolumab, tremelimumab, pembrolizumab, etc). However, despite its high efficiency compared to standard chemotherapy, the therapy based on blocking immune check points is facing several problems, i.e., high therapy cost and severe negative autoimmune-related side effects. Unfortunately, this therapy helps to minority of the patients. Hence, further studies are required to improve its efficiency and safety, as well as to search for selection criteria of the patients who would benefit from the therapy. An appealing approach to reduce negative side effects from immune checkpoint inhibition is application of the blocking antibodies, aiming for ex vivo generation of patients’ activated immune cells for cancer therapy, thus avoiding systemic drug administration. Our aim was to elucidate influence of immune checkpoint blocking antibodies on the expression of CTLA-4 and PD-1 in such an in vitro model. First of all, we have determined quantities of lymphocyte receptors in peripheral blood of healthy volunteers, or cancer patients with disseminated melanoma. Moreover, we defined effect from the addition of antibodies against immune checkpoints on proportions of cells expressing CTLA-4 and PD-1 in the population of phytohemagglutininactivated lymphocytes. Our study demonstrated that, in presence of antibodies to either of the two checkpoints during in vitro cell activation, the blockade of specific target receptor is accompanied by reduced number of cells positive for another checkpoint. Hence, the antibodies directed against PD-1 or CTLA-4 seem to suppress both negative signal cascades at once, if tested under such experimental conditions. Noteworthy, the response to blocking antibodies for different immune checkpoints varied for different donors. Our data may be used for development of effective combinations of lymphocyte activators and immune check-point inhibitors, for in vitro generation of activated lymphocytes applied for adoptive cancer therapy, as well as for prediction of possible responses to antibodies against CTLA-4 or PD-1, aiming to select the best personalized cancer immunotherapy

    Clinical case of heavy preeclampsia, complicated by complete mudderable placenta and antenatal fetal death

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    The article deals with a clinical case of delivery of a 29 years old primipara patient, upon admission to the emergency department of the Perinatal Center, who was diagnosed with premature placental abruption, antenatal fetal death and preeclampsia, as well as HELLP syndrome. On the operation of Cesarean section, the Cuveler's uterus was revealed, the question of the preservation of the reproductive organ was resolved. The use of a complex of measures for the correct intraoperative obstetric tactics made it possible to preserve the uterus and the possibility of the primipara in the future to realize their reproductive function.В статье рассмотрен клинический случай родоразрешения первородящей пациентки 29 лет, при поступлении в приёмное отделение Перинатального центра у которой диагностированы преждевременная отслойка плаценты, антенатальная гибель плода и преэклампсия, а также HELLP- синдром. На операции кесарева сечения выявлена матка Кювелера, решался вопрос о сохранении репродуктивного органа. Применение комплекса мероприятий по верной интраоперационной акушерской тактике позволили сохранить матку и возможность первородящей в дальнейшем реализовать свою репродуктивную функцию

    Clinical case of heavy preeclampsia, complicated by complete mudderable placenta and antenatal fetal death

    Get PDF
    The article deals with a clinical case of delivery of a 29 years old primipara patient, upon admission to the emergency department of the Perinatal Center, who was diagnosed with premature placental abruption, antenatal fetal death and preeclampsia, as well as HELLP syndrome. On the operation of Cesarean section, the Cuveler's uterus was revealed, the question of the preservation of the reproductive organ was resolved. The use of a complex of measures for the correct intraoperative obstetric tactics made it possible to preserve the uterus and the possibility of the primipara in the future to realize their reproductive function.В статье рассмотрен клинический случай родоразрешения первородящей пациентки 29 лет, при поступлении в приёмное отделение Перинатального центра у которой диагностированы преждевременная отслойка плаценты, антенатальная гибель плода и преэклампсия, а также HELLP- синдром. На операции кесарева сечения выявлена матка Кювелера, решался вопрос о сохранении репродуктивного органа. Применение комплекса мероприятий по верной интраоперационной акушерской тактике позволили сохранить матку и возможность первородящей в дальнейшем реализовать свою репродуктивную функцию

    Detection of the Initial Region of the Current Transformer Core Saturation

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    In the first part of the paper the detailed analysis of the existing current transformer (CT) saturation detection methods with their classification is presented. A new saturation detection method has been proposed in second part of the paper. Mathematical description of the method is given. In the next section of the paper a CT model with test scheme is presented. To identify the reliability of proposed method against nose and remanent flux density experiments have been produced in the fourth section. Comparative analysis between proposed and existing methods is also given. Finally, in conclusion a detailed description of the method is given regarding its behavior with respect to remanent flux and noise. © 2021, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved.Proposed results are the outcome of work on the topic "Development and testing algorithms and technical solutions for digital control of power facilities" within integrated project "Improvement of approaches to digital management of power facilities"
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