151 research outputs found

    Comparison of Spider-Robot Information Models

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    The paper deduces a mathematical model of a spider-robot with six three-link limbs. Many limbs with a multi-link structure greatly complicate the process of synthesizing a model, since in total the robot has twenty-four degrees of freedom, i.e., three coordinates of the center of mass of the body in space, three angles of rotation of the body relative to its center of mass and three degrees of freedom for each limb, to describe the position of the links. The derived mathematical model is based on the Lagrange equations with a further transformation of the equations to the Cauchy normal form in a matrix form. To test the resulting model in a SimInTech environment, an information model is synthesized and two simple experiments ar carried out to simulate the behavior of real spiders: moving forward in a straight line and turning in place at a given angle. The experimental results demonstrate that the synthesized information model can well cope with the tasks and the mathematical model underlying it can be used for further research

    Production of hemo- and immunoregulatory cytokines by erythroblast antigen(+ )and glycophorin A(+ )cells from human bone marrow

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    BACKGROUND: Erythroid nuclear cells (ENC) of the bone marrow (BM) have not previously been considered as important producers of wide spectrum of haemo- and immunoregulatory cytokines. The aim of the current work was to confirm the production of the main hemo- and immunoregulatory cytokines in human ENC from BM. RESULTS: We used native human BM ENC in our experiments. We for the first time have shown, that the unstimulated erythroblasts (Gl A(+ )or AG-EB(+)) produced a wide spectrum of immunoregulatory cytokines. Human BM ENC produce cytokines such as interleukn (IL)-1β, IL-2, IL-4, IL-6, interferon (IFN)-γ, transforming growth factor (TGF)-β1, tumor necrosis factor (TNF)-α and IL-10. They can be sub-divided into glycophorin A positive (Gl A(+)) and erythroblast antigen positive (AG-EB(+)) cells. To study potential differences in cytokine expression between these subsets, ENC were isolated and purified using specific antibodies to Gl A and AG-EB and the separated cells were cultivated for 24 hours. The cytokine contents of the supernatant were measured by electrochemiluminescence immunoassay. Quantitative differences in TGF-β1 and TNF-α production were found between Gl A(+ )and AG-EB(+ )BM ENC. Furthermore, in vitro addition of erythropoietin (EPO) reduced IFN-γ and IL-2 production specifically by the AG-EB(+ )ENC. Thus, Gl A(+ )and AG-EB(+ )ENC produce IL-1β, IL-2, IL-4, IL-6, IFN-γ, TGF-β1 and TNF-α. Gl A(+ )ENC also produce IL-10. CONCLUSION: Cytokine production by erythroid nuclear cells suggests that these cells might be involved in regulating the proliferation and differentiation of hematopoietic and immunocompetent cells in human BM

    ГЕМОДИНАМИЧЕСКИЕ ПАРАМЕТРЫ КРОВОТОКА В ЭКСТРАКРАНИАЛЬНЫХ ОТДЕЛАХ МОЗГОВЫХ АРТЕРИЙ И СЕРДЦЕ У БОЛЬНЫХ ОККЛЮЗИЕЙ ВНУТРЕННЕЙ СОННОЙ АРТЕРИИ ПРИ АНГИОХИРУРГИЧЕСКОМ ЛЕЧЕНИИ

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    HighlightsWe have analyzed the parameters of cerebral hemodynamics and left ventricular functional capacity in patients with occlusion and stenosis of the contralateral internal carotid artery during vascular surgery. Considering the importance of the left ventricular functional capacity and treatment options to ensure the stability of cerebral circulation in patients with occlusion and hemodynamically significant stenosis of the contralateral carotid artery, its detailed study at all stages of vascular surgery remains necessary. AbstractAim. To study cerebral hemodynamics and left ventricular functional capacity in patients with occlusion and stenosis of the contralateral internal carotid artery (ICA) to optimize treatment at the preoperative phase.Methods. The study compared the hemodynamic parameters of the blood flow of the ICA, vertebral arteries and left ventricular functional capacity in patients with ICA occlusion and contralateral ICA stenosis, which formed the 1 group (12 patients), and patients with unilateral hemodynamically significant stenosis, which formed the 2 group (52 patients). The blood flow in the extracranial portions of the major arteries of the head and heart was assessed using ultrasound, and the arterial vascular system and brain structure was assessed using MRI and MRA.Results. Before surgery, statistically significant differences in velocity parameters in the vertebral arteries on the occlusion side were found; on the contralateral occlusion side, velocity parameters in ICA were significantly different from the corresponding indicators in the group with unilateral stenosis; after surgery, statistically significant differences were found in the common carotid and vertebral arteries on the occlusion side; on the contralateral occlusion side, differences in velocity parameters in the common carotid, internal, and vertebral arteries were revealed in comparison with the group with unilateral stenosis. Of the indicators of the left ventricular functional capacity, only left ventricular ejection fraction differed significantly when comparing the group of patients with occlusion and stenosis of ICA and the group of patients with unilateral stenosis. Moreover, when evaluating pre- and postoperative outcomes in the group of patients with occlusion, significant differences were obtained only regarding the vertebral artery on the side of occlusion – the peak systolic blood flow velocity and the volumetric blood flow velocity significantly decreased. There were no significant differences between the common carotid, internal carotid arteries on the contralateral occlusion side, and middle cerebral arteries.Conclusion. Carrying out a comprehensive ultrasound examination of the main arteries of the head in combination with magnetic resonance imaging of the brain is a reliable and adequate way to assess cerebral hemodynamics, changes in the vascular bed and structure of the brain. Given the extreme importance of the left ventricular functional capacity to ensure the stability of cerebral circulation in patients with occlusion of the internal carotid artery and contralateral hemodynamically significant stenosis, its detailed study before carotid endarterectomy is necessary to adjust therapeutic measures.Основные положенияИзучены показатели мозговой гемодинамики и функциональной способности миокарда левого желудочка у пациентов с окклюзией и стенозом контралатеральной внутренней сонной артерии при ангиохирургическом лечении. Учитывая важность состояния функциональной способности миокарда левого желудочка и вариантов коррекции для обеспечения стабильности мозгового кровообращения у больных с окклюзией и гемодинамически значимым стенозом контралатеральной сонной артерии, ее детальное исследование на этапах ангиохирургического лечения представляется необходимым. РезюмеЦель. Исследование состояния мозговой гемодинамики и функциональной способности миокарда левого желудочка (ЛЖ) у пациентов с окклюзией и стенозом контралатеральной внутренней сонной артерии (ВСА) для оптимизации лечения на этапе предоперационной подготовки.Материалы и методы. В исследовании сравнивались гемодинамические параметры кровотока ВСА, позвоночных артерий и функциональной способности миокарда ЛЖ у пациентов с окклюзией ВСА и стенозом контралатеральной ВСА, группа 1 (12 пациентов), и пациентов с односторонним гемодинамически значимым стенозом – группа 2 (52 пациента). Состояние кровотока в экстракраниальных отделах магистральных артерий головы и сердца оценивали с использованием ультразвукового исследования, состояние артериальной сосудистой системы и структуры головного мозга – с применением магнитно-резонансной томографии и магнитно-резонансной томографии-ангиографии.Результаты. До операции на стороне окклюзии выявлены статистически значимые различия скоростных показателей в позвоночных артериях, на контралатеральной окклюзии стороне скоростные показатели в ВСА статистически значимо отличались от соответствующих показателей в группе с односторонним стенозом. После операции на стороне окклюзии определены статистически значимые различия в общих сонных и позвоночной артериях, на контралатеральной окклюзии стороне обнаружены различия скоростных показателей в общих сонных, внутренних и позвоночных артериях в сравнении с группой с односторонним гемодинамически значимым стенозом. Из показателей функциональной способности миокарда ЛЖ статистически значимо различались только фракция выброса ЛЖ при сравнении группы пациентов с сочетанием окклюзии и стеноза ВСА и односторонним гемодинамически значимым стенозом. Кроме этого, при оценке до- и послеоперационных результатов исследования непосредственно в группе пациентов с окклюзией статистически значимые различия получены лишь для позвоночной артерии на стороне окклюзии – значительно снизилась пиковая систолическая скорость и объемная скорость кровотока. В общих сонных, внутренних сонных на контралатеральной окклюзии стороне, средних мозговых артериях статистически значимых различий не выявлено.Заключение. Комплексное ультразвуковое исследование магистральных артерий головы в сочетании с магнитно-резонансной томографией головного мозга является надежным и адекватным способом оценки мозговой гемодинамики, изменений сосудистого русла и структуры головного мозга. Учитывая чрезвычайную важность состояния функциональной способности миокарда ЛЖ для обеспечения стабильности мозгового кровообращения у пациентов с окклюзией ВСА и контралатеральным гемодинамически значимым стенозом, ее детальное исследование перед каротидной эндартерэктомией представляется необходимым для коррекции лечебных мероприятий

    Challenges in QCD matter physics - The Compressed Baryonic Matter experiment at FAIR

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    Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter.Comment: 15 pages, 11 figures. Published in European Physical Journal

    Alignment of the CMS tracker with LHC and cosmic ray data

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    © CERN 2014 for the benefit of the CMS collaboration, published under the terms of the Creative Commons Attribution 3.0 License by IOP Publishing Ltd and Sissa Medialab srl. Any further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation and DOI.The central component of the CMS detector is the largest silicon tracker ever built. The precise alignment of this complex device is a formidable challenge, and only achievable with a significant extension of the technologies routinely used for tracking detectors in the past. This article describes the full-scale alignment procedure as it is used during LHC operations. Among the specific features of the method are the simultaneous determination of up to 200 000 alignment parameters with tracks, the measurement of individual sensor curvature parameters, the control of systematic misalignment effects, and the implementation of the whole procedure in a multi-processor environment for high execution speed. Overall, the achieved statistical accuracy on the module alignment is found to be significantly better than 10μm

    Документальная публикация — книга как одна из форм обеспечения востребованности и доступности исторической памяти россиян

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    On the International scientific conference The Rumyantsev Readings, taken place in the Russian state library on April, 20-22th, 2010.В Российской государственной библиотеке (РГБ) 20—22 апреля 2010 г. прошла ежегодная международная научная конференция «Румянцевские чтения». Публикуем выступления участника пленарного заседания конференции: В.П. Козлов

    Solitary waves on constant vorticity flows with an interior stagnation point

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    The two-dimensional free-boundary problem describing steady gravity waves with vorticity on water of finite depth is considered. Under the assumption that the vorticity is a negative constant whose absolute value is sufficiently large, we construct a solution with the following properties. The corresponding flow is unidirectional at infinity and has a solitary wave of elevation as its upper boundary; under this unidirectional flow, there is a bounded domain adjacent to the bottom, which surrounds an interior stagnation point and is divided into two subdomains with opposite directions of flow by a critical level curve connecting two stagnation points on the bottom.Funding Agencies|Swedish Research Council (VR)Swedish Research Council [2017-03837]; Linkoping University</p

    Scientific and pedagogical schools «System analysis in engineering and control» and its contribution to educational the process of universities

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    In 2018, the 20th anniversary of the Scientific and Pedagogical School “System Analysis in Engineering and Control”, which unites scientists who developing the Theory of Systems and System Analysis in various universities in Russia, Ukraine, Norway, Poland, USA, Finland and other countries.The school considers itself to be a successor of: the school of the Moscow Energy Institute, in which Dr. of Technical Sciena, Professor F.E. Temnikov (1906-1993), created in 1970 the first in the country the department in the direction of the theory of systems and system studies, the Department of System Engineering$ and the school of the Leningrad Polytechnic Institute (now Peter the Great St. Petersburg Polytechnic University), which since 1973 at the Faculty of Technical Cybernetics Doctor of Technical Sciences, Professor, (later -Honored Scientist of the Russian Federation) A.A. Denisov (1934-2010) studied the generality of processes in systems of various physical nature and also proposed the theory of the information field and information, approach to analysis of system.In 1994, Dr. Tech. Professor, Honored Worker of the Higher School of the Russian Federation, VN Kozlov, renamed the Department of Technical Cybernetics headed by him, to the Depart-ment”System Analysis and Management” and opened a new direction of the same name for the preparation of bachelors and masters,and this is played a major role in the establishment of the Polytechnic University scientific and pedagogical school.Since 1998, on the basis of the Polytechnic University, a conference “System Analysis in Engineering and Control” has been held annually, which has become the basis for the formation of a school with the same name of unifying scientists from Russian and foreign universities and research institutes involved in the development the Theory of Systems and System Analysis as applied theory of systems..This article is characterized by the main results, which over the past 20 years, scientists, united by the school, made contribution to the development of Theory of Systems, System Analysis and other scientific directions
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