67 research outputs found

    Ugra first institutuion of higher education: way from branch to university

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    В статье показана 25-летняя история Нижневартовского государственного университета, его достижения и проблемы. Даны результаты опросов по проблеме высшего образования.The article reveals the 25 year history of Nizhnevartovsk State University, its achievements and challenges. The polling results on the problems of education are presented

    Lepidoptera (Insecta) of proposed specially protected natural area "Belokurikha nature park" (Northern Altai). First results

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    149 Lepidoptera species from 16 families were reported for the territory of the proposed protected area "Belokurikha Natural Park". This list is the primary data on the fauna of Lepidoptera in the region. Most of the species belongs to Euro-Siberian and Transpalaearctic groups

    REGIONAL GENOTYPES OF HELICOBACTER PYLORI IN CHILDREN WITH GASTRODUODENAL PATHOLOGY IN THE REPUBLIC OF BASHKORTOSTAN

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    Purpose: To investigate regional variants of H. pylori genotypes.Materials and methods: Regional variants of H. pylori genotypes have been studied (Cag A, Vac A, Ice A, Bab A2) in clinical strains of H. pylori, obtained from 91 paediatric patients (mean age 14.3±1.6 years), with gastroduodenal pathology in the Republic of Bashkortostan.Results: Marker of pathogenicity island Cag A was revealed in 42 patients (46.1%), Bab A2 – in 31 (34%), Vac A genotype S1 - in 59 (64.8%) and S2 - in 32 (35.2%), Ice A1 - in 72 (79.1%), Ice A2 - in 19 (20.9%).Summary: Among the patients with peptic ulceration, H. pylori strains, carrying markers of pathogenicity island Cag A / Vac AS1 in combination with Bab A2 were detected significantly more often

    Scaling Tests of the Cross Section for Deeply Virtual Compton Scattering

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    We present the first measurements of the ep → epγ cross section in the deeply virtual Compton scattering (DVCS) regime and the valence quark region. The Q2 dependence (from 1.5 to 2.3 GeV2) of the helicity-dependent cross section indicates the twist-2 dominance of DVCS, proving that generalized parton distributions (GPDs) are accessible to experiment at moderate Q2. The helicity-independent cross section is also measured at Q2=2.3 GeV2. We present the first model-independent measurement of linear combinations of GPDs and GPD integrals up to the twist-3 approximation

    A precise extraction of the induced polarization in the 4He(e,e'p)3H reaction

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    We measured with unprecedented precision the induced polarization Py in 4He(e,e'p)3H at Q^2 = 0.8 (GeV/c)^2 and 1.3 (GeV/c)^2. The induced polarization is indicative of reaction-mechanism effects beyond the impulse approximation. Our results are in agreement with a relativistic distorted-wave impulse approximation calculation but are over-estimated by a calculation with strong charge-exchange effects. Our data are used to constrain the strength of the spin independent charge-exchange term in the latter calculation.Comment: submitted to Physical Review Letter

    Polarization Transfer in the 4He(e,e'p)3H Reaction at Q^2 = 0.8 and 1.3 (GeV/c)^2

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    Proton recoil polarization was measured in the quasielastic 4He(e,e'p)3H reaction at Q^2 = 0.8 (GeV/c)^2 and 1.3 (GeV/c)^2 with unprecedented precision. The polarization-transfer coefficients are found to differ from those of the 1H(e,e' p) reaction, contradicting a relativistic distorted-wave approximation, and favoring either the inclusion of medium-modified proton form factors predicted by the quark-meson coupling model or a spin-dependent charge-exchange final-state interaction. For the first time, the polarization-transfer ratio is studied as a function of the virtuality of the proton

    JLab Measurement of the 4^4He Charge Form Factor at Large Momentum Transfers

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    The charge form factor of ^4He has been extracted in the range 29 fm2^{-2} Q277\le Q^2 \le 77 fm2^{-2} from elastic electron scattering, detecting 4^4He nuclei and electrons in coincidence with the High Resolution Spectrometers of the Hall A Facility of Jefferson Lab. The results are in qualitative agreement with realistic meson-nucleon theoretical calculations. The data have uncovered a second diffraction minimum, which was predicted in the Q2Q^2 range of this experiment, and rule out conclusively long-standing predictions of dimensional scaling of high-energy amplitudes using quark counting.Comment: 4 pages, 2 figure

    JLab Measurements of the 3He Form Factors at Large Momentum Transfers

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    The charge and magnetic form factors, FC and FM, of 3He have been extracted in the kinematic range 25 fm-2 < Q2 < 61 fm-2 from elastic electron scattering by detecting 3He recoil nuclei and electrons in coincidence with the High Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The measurements are indicative of a second diffraction minimum for the magnetic form factor, which was predicted in the Q2 range of this experiment, and of a continuing diffractive structure for the charge form factor. The data are in qualitative agreement with theoretical calculations based on realistic interactions and accurate methods to solve the three-body nuclear problem

    Low Q^2 measurements of the proton form factor ratio mupGE/GMmu_p G_E / G_M

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    We present an updated extraction of the proton electromagnetic form factor ratio, mu_p G_E/G_M, at low Q^2. The form factors are sensitive to the spatial distribution of the proton, and precise measurements can be used to constrain models of the proton. An improved selection of the elastic events and reduced background contributions yielded a small systematic reduction in the ratio mu_p G_E/G_M compared to the original analysis.Comment: 12 pages, 5 figures, archival paper for proton form factor extraction from Jefferson Lab "LEDEX" experimen
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