1,471 research outputs found

    Features of Physical Development of Schoolchildren in the Conditions of Specialized Training

    Get PDF
    The article presents a comparative analysis of physical development of 13-year-olds and cadet basic profile of teaching in urban schools in the parameters of somatometry and visiometry characterizing physical development, functional state, adaptation of the heart and body to current training loads. Coming of puberty is marked by intense growth of the body with heterochronous changes in the proportions and dimensions of its muscular skeletal system and the structure of internal organs. During this period, the role of mechanisms for self-regulation of heart activity and, in general, autonomous regulation of the functions of the cardiovascular system increases. At the initial stage in adolescents the manifestation of tachycardia and cardiac type of self-regulation of blood circulation increases. It is accompanied with deterioration in inotropic function of the myocardium against the background of a pronounced effect of sympatotonia and vagotonia on the systolic function of the myocardium

    Single layer and multilayer vacuum-arc coatings based on the nitride tialsiyn: composition, structure, properties

    Get PDF
    Using high-technological vacuum-arc evaporation in the atmosphere of nitrogen with ion bombardment, single- and multilayer coatings based on TiAlSiYN with high mechanical characteristics were obtained: hardness of the coatings reached 49.5 GPA, resistance to wear, with the value of the critical point LC5 reaching 184.92 N. The mechanisms of structure formation, defining the resulting mechanical characteristics of single- and multi-layer coatings based on TiAlSiYN nitride have been discusse

    Hemodynamic criteria of the circulatory system in ethnic groups of students with different types of autonomic regulation of the heart rate

    Get PDF
    Under physiological conditions, the first years of university studies of the students of Arabic and African subgroups with MPAR and PPAR HR were characterized by toughness, low effectiveness of the system of blood circulation, increased peripheral vascular resistance, vascular TSC; Indian and Latino-American subgroups with MPAR HR revealed the weakness and low efficiency of the circulatory system, the optimal GPBC and cardiovascular TSC were revealed in Indian and Latino-American subgroups with MPAR HR, and subgroups with PPAR HR showed high endurance of the circulatory syste

    Features of physical development of schoolchildren in the conditions of specialized training

    Get PDF
    The article presents a comparative analysis of physical development of 13-year-olds and cadet basic profile of teaching in urban schools in the parameters of somatometry and visiometry characterizing physical development, functional state, adaptation of the heart and body to current training loads. Coming of puberty is marked by intense growth of the body with heterochronous changes in the proportions and dimensions of its muscular skeletal system and the structure of internal organs. During this period, the role of mechanisms for self-regulation of heart activity and, in general, autonomous regulation of the functions of the cardiovascular system increase

    Effect of photoions on the line shapes of the F\"orster resonance and microwave transitions in cold rubidium Rydberg atoms

    Full text link
    Experiments on the spectroscopy of the F\"orster resonance Rb(37P)+Rb(37P) -> Rb(37S)+Rb(38S) and microwave transitions nP -> n'S, n'D between Rydberg states of cold Rb atoms in a magneto-optical trap have been performed. Under ordinary conditions, all spectra exhibited a 2-3 MHz line width independently of the interaction time of atoms with each other or with microwave radiation, although the ultimate resonance width should be defined by the inverse interaction time. Analysis of the experimental conditions has shown that the main source of the line broadening was the inhomogeneous electric field of cold photoions appeared at the excitation of initial Rydberg nP states by broadband pulsed laser radiation. Using an additional pulse of the electric field, which rapidly removed the photoions after the laser pulse, lead to a substantial narrowing of the microwave and F\"orster resonances. An analysis of various sources of the line broadening in cold Rydberg atoms has been conducted.Comment: 10 pages, 6 figure

    A wood-filled composite based on recycled polyethylene terephthalate. Production and properties

    Get PDF
    The possibility of conducting combined recycling of wood and PETP waste was investigated. The aim was to develop a process for producing composites based on recycled PETP filled with wood flour by the depolymerisation of recycled polymer to polyol, the production of unsaturated polyester, and its subsequent polymerisation with filler into products. The mechanisms of the principal processes occurring in the production of the composite were examined. It was shown that the wood-filled composite produced could be processed by pressing to produce products such as boards, panels, trays and sheets. The properties of the composite (density, elastic modulus, elongation at break and impact strength) were compared with those of a traditional wood-plastic composite. 6 ref

    Dynamic model of elastoplastic normal collision of spherical particles under nonlocal plasticity

    Get PDF
    The problem of normal collision of a spherical particle with a half-space is considered with allowance for nonlocal plastic deformation in the case where the strength limit depends on the contact radius, as well as for the strengthening effect in the deformed material. The dimensionless coefficient of normal velocity restitution has been calculated numerically as a function of the initial velocity of the spherical particle. The obtained data coincide well with experimental results available in the literature

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

    Get PDF
    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

    Get PDF
    A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

    Les Houches 2015: Physics at TeV Colliders Standard Model Working Group Report

    Get PDF
    This Report summarizes the proceedings of the 2015 Les Houches workshop on Physics at TeV Colliders. Session 1 dealt with (I) new developments relevant for high precision Standard Model calculations, (II) the new PDF4LHC parton distributions, (III) issues in the theoretical description of the production of Standard Model Higgs bosons and how to relate experimental measurements, (IV) a host of phenomenological studies essential for comparing LHC data from Run I with theoretical predictions and projections for future measurements in Run II, and (V) new developments in Monte Carlo event generators.Comment: Proceedings of the Standard Model Working Group of the 2015 Les Houches Workshop, Physics at TeV Colliders, Les Houches 1-19 June 2015. 227 page
    corecore