263 research outputs found

    Increase housing provision of citizens as a priority direction of social and economic development of the region

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    Set out the results of the study provide citizens with housing as a priority direction of social and economic development of the market; showed the causes of low housing provision of citizens of the Belgorod region, made conclusions and identified measures to increase housing provision in the cities of RussiayesBelgorod State National Research Universit

    From the Economic Union to the Harmonisation of Higher Education in the BRICS Countries: The Experience of RUDN University

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    Since 2009 when Brazil, Russia, India, and China (South Africa since 2011) joined in the international organisation aimed at the economic development of the countries, and gain financial stability, the relations between the countries too boosted via political and cultural cooperation. The new economic, political and social environment has a high demand for competent specialists ready to work in various national agendas and interrelated frameworks of the BRICS. In this context, it is argued that professional training in the countries under discussion should be correlated as it provides grounds for quality assurance in education that contributes to the nations’ sustainable development, safety, and human rights provision. This situation determines the topicality of the issue. The objective of this research is to study the higher educational environment in the BRICS countries and to compare some aspects of professional training. In doing so, the study aims to present the experience of RUDN University as one of the BRICS university network members. The hypothesis states that the harmonisation of higher education systems within regional organisations can contribute to the enhancement of both international standards and individual learning paths, thus fostering youth rights for education in line with quality standards and individual preferences. To accomplish the objectives of the study, it uses the following methods - the review of the current research, formal document and online resources on higher education in the BRICS countries; the survey of the undergraduates, graduates, and postgraduates on their motivation to academic mobility, and collaboration in the frameworks of BRICS higher education. The data has been analysed employing the methods of statistical processing, qualitative and quantitative methods. The findings of the current research include the outcomes and findings on the harmonisation of higher education in the frameworks of BRICS higher education. The study will contribute to further development of BRICS countries education and the harmonisation of higher education. &nbsp

    Orbitally induced hierarchy of exchange interactions in zigzag antiferromagnetic state of honeycomb silver delafossite Ag3Co2SbO6

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    We report the revised crystal structure, static and dynamic magnetic properties of quasi-two dimensional honeycomb-lattice silver delafossite Ag3Co2SbO6. The magnetic susceptibility and specific heat data are consistent with the onset of antiferromagnetic long range order at low temperatures with N\'eel temperature TN ~ 21.2 K. In addition, the magnetization curves revealed a field-induced (spin-flop type) transition below TN in moderate magnetic fields. The GGA+U calculations show the importance of the orbital degrees of freedom, which maintain a hierarchy of exchange interaction in the system. The strongest antiferromagnetic exchange coupling was found in the shortest Co-Co pairs and is due to direct and superexchange interactions between the half-filled xz+yz orbitals pointing directly to each other. The other four out of six nearest neighbor exchanges within the cobalt hexagon are suppressed, since for these bonds active half-filled orbitals turned out to be parallel and do not overlap. The electron spin resonance (ESR) spectra reveal a Gaussian shape line attributed to Co2+ ion in octahedral coordination with average effective g-factor g=2.3+/-0.1 at room temperature and shows strong divergence of ESR parameters below 120 K, which imply an extended region of short-range correlations. Based on the results of magnetic and thermodynamic studies in applied fields, we propose the magnetic phase diagram for the new honeycomb-lattice delafossite

    Static and dynamic magnetic response of fragmented haldane-like spin chains in layered Li3Cu2SbO6

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    The structure and the magnetic properties of layered Li3Cu2SbO6 are investigated by powder X-ray diffraction, static susceptibility, and electron spin resonance studies up to 330 GHz. The XRD data experimentally verify the space group C2=m with halved unit cell volume in contrast to previously reported C2=c. In addition, the data show significant Li=Cuintersite exchange. Static magnetic susceptibility and ESR measurements show two magnetic contributions, i.e., quasifree spins at low-temperature and a spin-gapped magnetic subsystem, with about half of the spins being associated to each subsystem. The data suggest ferromagnetic-antiferromagnetic alternating chains with JFM = -285 K and JAFM = 160 K with a significant amount of Li-defects in the chains. The results are discussed in the scenario of fragmented 1D S = 1 AFM chains with a rather high defect concentration of about 17% and associated S =1=2 edge states of the resulting finite Haldane chains. © 2016 The Physical Society of Japan

    Barium vanadium silicate BaVSi2O7: A t2g counterpart of the Han purple compound

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    By means of thermodynamic and magnetic resonance measurements the S = 1/2 dimer system BaVSi2O7 is characterized. A broad maximum in the temperature dependence of the magnetic susceptibility and a Schottky-type anomaly in the specific heat allows estimating the main exchange interaction within V4+-V4+ dimers as J=37±1 K. This estimation is confirmed by pulsed magnetic field measurements of the magnetization, which is evidenced by the field-induced singlet-triplet transition at about 27 T. Both X-band and high-field terahertz electron spin resonance data qualitatively agree with the results of the specific heat and magnetization measurements. The electronic structure calculations, by using local density approximation, indicate that the magnetic properties of BaVSi2O7 can be interpreted within the weakly interacting dimer model. © 2013 American Physical Society

    Hormone therapy affecting interferon defense in children with infectious mononucleosis

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    23 children diagnosed with acute infectious mononucleosis were hospitalized and examined after a short prednisolone treatment course. Related interferon status during infection was compared with that in 38 patients with acute infectious mononucleosis receiving no hormone therapy. Interferon status was investigated by Ershov method, allowing to estimate amount of interferon in the blood serum samples or patient blood cell culture by assessing interferon biological activity. Along with measuring IFNα or IFNγ biological activity, their level was quantified by using enzyme immunoassay. Immunological examination conducted on the next day after the end of hormone therapy revealed sharply decreased potential of patient blood cells to produce both IFNα and IFNγ. The multiplicity of IFNα and IFNγ titer reduction in various patients varied by 4–5 and 3–4-fold, respectively. The concentration of IFNα, determined by ELISA, decreased by 4–6-fold, whereas for IFNγ — by 1.5–2-fold. A follow-up examination 1 month after discharge from the clinic showed that mean IFNα titer in children aged 3–6 years and treated with prednisolone was significantly reduced compared to the baseline, whereas most patients receiving no hormone therapy had normal IFNα production. The change in the level of IFNα 1 month after hormone therapy in 7–14-year age group was similar. IFNγ production quickly recovered, and 1 month after discharge from the clinic, its concentration in culture supernatants from patients reached 10–15 ng/ml, exceeding normal values more than twice. The biological activity of IFNγ in these culture supernatants was significantly higher than those immediately after hormone therapy, whereas in 3–6-year-old group of patients it was also higher than baseline level. These results can serve as a laboratory justification for including recombinant IFNα-2b drugs in the therapy of such patients, presumably immediately after the end of hormone course. Overall, laboratory justified administration of interferon preparations seems to be necessary to determine optimal timepoint for applying such drugs to increase effectiveness for achieving a durable patient recovery

    Preparation and characterization of metastable trigonal layered MSb2O6 phases (M = Co, Ni, Cu, Zn, and Mg) and considerations on FeSb2O6

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    MSb2O6 compounds (M = Mg, Co, Ni, Cu, Zn) are known in the tetragonal trirutile forms, slightly distorted monoclinically with M = Cu due to the Jahn-Teller effect. In this study, using a low-temperature exchange reaction between ilmenite-type NaSbO3 and molten MSO4-KCl (or MgCl2-KCl) mixtures, these five compositions were prepared for the first time as trigonal layered rosiaite (PbSb2O6)-type phases. Upon heating, they irreversibly transform to the known phases via amorphous intermediates, in contrast to previously studied isostructural MnSb2O6, where the stable phase is structurally related to the metastable phase. The same method was found to be applicable for preparing stable rosiaite-type CdSb2O6. The formula volumes of the new phases show an excellent correlation with the ionic radii (except for M = Cu, for which a Jahn-Teller distortion is suspected) and are 2-3% larger than those for the known forms although all coordination numbers are the same. The crystal structure of CoSb2O6 was refined via the Rietveld method: P31m, a = 5.1318(3) Å, and c = 4.5520(3) Å. Compounds with M = Co and Ni antiferromagnetically order at 11 and 15 K, respectively, whereas the copper compound does not show long-range magnetic order down to 1.5 K. A comparison between the magnetic behavior of the metastable and stable polymorphs was carried out. FeSb2O6 could not be prepared because of the 2Fe2+ + Sb5+ = 2Fe3+ + Sb3+ redox reaction. This electron transfer produces an additional 5s2 shell for Sb and results in a volume increase. A comparison of the formula volume for the stable mixture FeSbO4 + 0.5Sb2O4 with that extrapolated for FeSb2O6 predicted that the trirutile-type FeSb2O6 can be stabilized at high pressures. © 2017 The Royal Society of Chemistry.The work was supported by the Russian Foundation for Basic Research under the grant 14-03-01122. A. N. V. acknowledges the support in part from the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST (no. K2-2016-066) and by Act 211 of the Government of Russian Federation, contract no. 02.A03.21.0006
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