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Specific features of Eu^(3+) and Tb^(3+) magnetooptics in gadolinium-gallium garnet (Gd_3Ga_5O_(12))

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Journal of Rare Earths 2011年第8期29卷 776-782页

作者： Uygun V. Valiev John b. Gruber 付德君 Vasiliy O. Pelenovich Gary W. burdick mariya E. Malysheva Faculty of Physics National University of Uzbekistan Department of Physics and Astronomy The University of Texas at San Antonio Department of Physics Wuhan University Department of Physics Andrews University

We reported magnetooptical properties of Eu3＋（4f（6）） and Tb3＋（4f（8）） in single crystals of Gd3Ga5O12 （GGG）, Y3Ga5O12 （YGG）, and Eu3＋（4f（6）） in Eu3Ga5O12 （EuGG） for both ions occupying sites of D2 symmetry in the garnet structure. Absorption, luminescence, and magnetic circular polarization of luminescence （MCPL） spectra of Tb3＋ in GGG and YGG and absorption and magnetic circular dichroism （MCD） of Eu3＋ in EuGG were studied. The data were obtained at 85 K and room temperature （RT）. Magnetic susceptibility of Eu3＋ in EuGG was also measured between 85 K and RT. The magnetooptical and magnetic susceptibility data were modeled using the wavefunctions of the crystal-field split energy （Stark） levels of Eu3＋ and Tb3＋ occupying D2 sites in the same garnets. The results reported gave a precise determination of these Stark level assignments and confirmed the symmetry labels （irreducible representations） of the closely-spaced Stark levels （quasi-doublets） found in the 5D1 （Eu3＋） and 5D4 （Tb3＋） multiplets. Ultraviolet （UV） excitation （300 nm） of the 6PJ and 6IJ states of Gd3＋ in the doped GGG crystals led to emission from 5D4 （Tb3＋） and 5D1 and 5D0 （Eu3＋） through radiationless energy transfer to the 4f（n–1）5d band of Tb3＋ and to UV quintet states of Eu3＋. The temperature-dependent emission line shapes and line shifts of the magnetooptical transitions excited by UV radiation suggested a novel way to explore energy transfer mechanisms in this rare-earth doped garnet system.

关键词： magnetic circular polarization of luminescence magnetic circular dichroism absorption quantum qutting energy transfer magnetic susceptibility rare earths

Comparative investigations of structure and properties of micro-arc wollastonite-calcium phosphate coatings on titanium and zirconiumniobium alloy

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bioactive Materials 2017年第3期2卷 177-184页

作者： M.b.sedelnikova E.G.Komarova Yu.P.Sharkeev T.V.Tolkacheva I.A.Khlusov L.S.Litvinova K.A.Yurova V.V.Shupletsova Institute of Strength Physics and Materials Science of Sb RAS Academicheskii pr.2/4634055TomskRussia National Research Tomsk Polytechnic University Lenina pr.30634050TomskRussia Siberian State Medical University 2 Moskovsky tr.634050TomskRussia Immanuel Kant baltic Federal University 14 A.Nevskogo st.236041KaliningradRussia

Investigation results of micro-arc wollastoniteecalcium phosphate(W-CaP)biocoatings on the pure titanium(Ti)and Zr-1wt.%Nb(Zr-1Nb)alloy were *** voltages of 150-300 V generate the micro-arc oxidation(MAO)process with the initial amplitude current of 150-550 A and 100-350 A for Ti and Zr-1Nb substrates,*** identical dependencies of changes of the coating thickness,surface roughness and adhesion strength on the process voltage were revealed for the both *** W-CaP coatings with the thickness of 10-11μm were formed on Ti and Zr-1Nb under the low process voltage of 130-150 *** wollastonite particles with the size in the range of 40-100μm were observed in such *** structure of the coatings on Ti was presented by the X-ray amorphous and crystalline *** X-ray reflexes relating to the crystalline phases of Ti and wollastonite were observed only in XRD patterns of the coatings deposited under 130-200 V on ***,the crystalline structure with phases of CaZr4(PO4)6,β-ZrP2O7,ZrO2,and Zr was detected in the coatings on ***-IRS,XRD,SEM,and TEM data confirmed that the increase of the process voltage to 300 V leads to the dissociation of the *** toxic effect of specimens on a viability,morphology and motility of human adipose-derived multipotent mesenchymal stem cells was revealed in vitro.

关键词： Micro-arc oxidation biocoatings Calcium phosphate Wollastonite

Neuroimaging Phenomenology of the Central Self-Regulation Mechanisms

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Journal of behavioral and brain Science 2014年第1期4卷 58-68页

作者： Mark b. Shtark Kseniya Mazhirina mariya Rezakova Andrey Savelov Mikhail Pokrovskiy Olga Jafarova Company “biofeedback Computer Systems” Novosibirsk Russia Research Institute “International Tomography Center” Siberian Branch of the Russian Academy of Sciences Novosibirsk Russia Research Institute of Molecular biology and biophysics Siberian Branch of the Russian Academy of Medical Sciences Novosibirsk Russia

Functional MRI was used to map the brains of subjects on-line during the process of media training for the acquisition and improvement of self-regulation mechanisms. The temporal and spatial dynamics of the new neural network formation were studied in real and simulated (false) biofeedback game, and their qualitative characteristics were discussed. It has been shown that immersion into a virtual competitive game, controlled by physiological responses, causes a wide involvement of the cortices, characterized by a high volume of activation in the mid-temporal, occipital and frontal areas, the cuneus and the precuneus. In both forms of media training, high values of activation volume were identified in the cerebellar structures.

关键词： Functional Magnetic Resonance Imaging Adaptive Feedback Real and Imitation biofeedback Self-Regulation Strategies

Tuning the melting point and phase stability of rare-earth oxides to facilitate their crystal growth from the meltv

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Journal of Advanced Ceramics 2022年第9期11卷 1479-1490页

作者： Matheus PIANASSOLA Kaden L.ANDERSON Joshua SAFIN Can AGCA Jake W.MCMURRAY bryan C.CHAKOUMAKOS Jöerg C.NEUEFEIND Charles L.MELCHER mariya ZHURAVLEVA Scintillation Materials Research Center The University of TennesseeKnoxville 37996USA Department of Materials Science and Engineering The University of TennesseeKnoxville 37996USA Materials Science and Technology Division Oak Ridge National LaboratoryOak Ridge 37831USA Neutron Scattering Division Oak Ridge National LaboratoryOak Ridge 37831USA Department of Nuclear Engineering The University of TennesseeKnoxville 37996USA

The challenge of growing rare-earth(RE)sesquioxide crystals can be overcome by tailoring their structural stability and melting point via composition *** work contributes to the advancement of the field of crystal growth of high-entropy oxides.A compound with only small REs(Lu,Y,Ho,Yb,Er)_(2)O_(3)maintains a cubic C-type structure upon cooling from the melt,as observed via in-situ high-temperature neutron diffraction on aerodynamically levitated *** the other hand,a compound with a mixture of small and large REs(Lu,Y,Ho,Nd,La)_(2)O_(3)crystallizes as a mixture of a primary C-type phase with an unstable secondary *** of compositions(Lu,Y,Ho,Nd,La)_(2)O_(3)and(Lu,Y,Gd,Nd,La)_(2)O_(3)were grown by the micro-pulling-down(mPD)method with a single monoclinic b-type phase,while a powder of(Lu,Y,Ho,Yb,Er)_(2)O_(3)did not melt at the maximum operating temperature of an iridium-rhenium *** minimization of the melting point of the two grown crystals is attributed to the mismatch in cation *** electron probe microanalysis reveals that the general element segregation behavior in the crystals depends on the composition.

关键词： high-entropy oxides crystallography neutron diffraction crystal growth

Possibility of “Comet-Like” Transport of Acetylcholine Receptors in Command HelixNeurons in Cellular Analog of Habituation

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World Journal of Neuroscience 2014年第2期4卷 133-143页

作者： Arkady S. Pivovarov Galina b. Murzina Denis A. Makhnovsky mariya S. Tret’yakova Department of Higher Nervous Activity Faculty of Biology Moscow Lomonosov State University Moscow Russia Institute of Higher Nervous Activity and Neurophysiology Russian Academy of Sciences Moscow Russia

The presence of "comet-like" radial transport of acetylcholine receptors by actin microfilaments without the participation of myosin motors in the depression of acetylcholine-induced inward chloric current (ACh-current) in command neurons of defensive behavior of the land snail, Helix lucorum, in a cellular analog of habituation was investigated. For that purpose the effects of CK548, CK-636 (inhibitors of actin-related protein complex Arp2/3, whose activation triggers rapid actin polymerization and the formation of the "comet-like" tail on the actinic filament) and wiskostatin (an N-WASP protein inhibitor, activating Arp2/3) on the depression of ACh-current were studied. The attenuation of ACh-current depression was observed upon the addition of CK548. At the same time, CK-636 and wiskostatin irreversibly strengthened the depression of this current and suppressed its spontaneous recovery. The results of CK-548 action and its mathematical modeling allow suggesting the presence of "comet-like" transport of acetylcholine receptors, initiated by Arp2/3 protein complex in receptor endo and exocytosis in command neurons of Helix lucorum in a cellular analog of habituation. Irreversible inhibition of vital metabolic processes of the neuron by wiskostatin and CK-636, which lead to the decrease in the level of ATP, could have caused irreversible effects of these blockers on current depression.

关键词： CK-548 CK-636 Wiskostatin Depression of Acetylcholine-Induced Inward Current Command Neurons Helix lucorum Cellular Analog of Habituation

Autocatalytic Photo-Oxidation Process of C3-C4 Fraction to Methanol

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Autocatalytic Photo-Oxidation Process of C3-C4 Fraction to M...

Quantum-Chemical Estimating Interaction of sp2-Carbon Nanoclusters with PE and PP Oligomers

2012 International Conference on Future Optical Materials and Circuit Design(FOMCD 2012)

作者： mariya G.Loriya Ayodeji A.Ijagbuji Alexei b.Tselishtev Ivan I.Zakharov Vladimir Dahl East Ukrainian National University Institute of Technology

The direct conversion of propane and butane fraction（existing as mixtures rather than separate products） to methanol as well as the reaction mechanism under visible light source（λ=420 nm） and the catalytic action of ·NO2 have been evaluated. The purpose of this work is to explore novel pathways for the production of methanol by suggesting a simplified model and result-oriented scheme to avoid the drawbacks associated with methane activation（incredibly high activation energy of about 440 k J/mol even under mild processing conditions） in the course of its transformation to methanol which is characterized by high yield and selectivity. It is important to consider propane and butane fraction（recovered from primary crude oil distillation and by cracking of heavy molecules） as a possible feedstock for methanol production exhibiting a sufficiently high degree of conversion per pass. Thereby, a relatively simple and economical method for methanol production from refined crude oil composed of propane and butane（a one step co-processing） have been tendered.

关键词： Propane-butane fraction Photo oxidation Reaction mechanism Conversion to methanol

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Journal of Materials Science and Chemical Engineering 2019年第7期7卷 1-11页

作者： Mykola Kartel Euvgeniy Demianenko Оksana Сherniuk mariya Terets Yurii Sementsov bo Wang Transportation and Logistics College Ningbo University of Technology Ningbo China Department of Nanoporous and Nanosized Carbon Materials O. Chuiko Institute of Surface Chemistry NASU Kyiv Ukraine

The purpose of this work was to examine the interaction of graphene-like nanoclusters with fragments of polymers of the same nature, but somewhat different structure, for example, polyethylene (PE) and polypropylene (PP) by means of quantum chemistry. by method of density functional theory with the exchange-correlation functional b3LYP, the basis set 6 - 31 G (d, p) and the Grimme’s dispersion correction, the energy values have been calculated of interaction between nanocarbon fragments and oligomers of PE and PP, the most probable structures of their intermolecular complexes being optimized. A graphene-like plane of 40 carbon atoms and 16 atoms of hydrogen was chosen as a model for the surface of the graphene and carbon nanotubes (CNT). In order to take into account the dimensional effect of the surface of the nanotube fragment model on the interaction energy, in addition to the above described, two larger models were used, with the general formula C54H18 and C96N24. It has been found that the interaction energy of nanocarbon fragment with an oligomer of PP is greater, compared with PE, which is consistent with the experimental data on melting temperatures of pure polymers and nanotube-polymer composites. The polymer with a surface of nanocarbon fragment forms an intermolecular complex not bound covalently and retained by intermolecular dispersion forces. Oligomers of polymeric matters and carbon surfaces in formed nanocomplex are placed closer to each other than separate polymeric links between them.

关键词： Nanocomposite Carbon Nanotube Polyethylene Polypropylene Density Functional Theory Method Cluster Approximation Dispersion Forces of Interaction

Nuclear accumulation of the photoreceptor UVR8 is regulated by COP1

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Nuclear accumulation of the photoreceptor UVR8 is regulated ...

Parents’s knowledge and awareness about hepatitis b can influence the vaccination of their children

2016年全国植物生物学大会

作者： Ruohe Yin mariya Skvortsova Sylvain Loubéry Roman Ulm Department of botany and Plant biology University of Geneva

Light plays critical roles throughout the lifecycle of plants. UV-b is an intrinsic component of solar radiation. Plants respond to UV-b through the UVR8 photoreceptor signaling pathway. Homodimeric UVR8 perceives UV-b via specific intrinsic aromatic amino acids as chromophores. This leads to rapid dimer dissociation. UVR8 monomers interact with CONSTITUTIVE PHOTOMORPHOGENIC 1(COP1) to relay the captured UV-b signal for UV-b photomorphogenesis. While it was described quite some years earlier that UV-b triggers UVR8 protein translocation from cytosol into nucleus,the molecular mechanism regulating this process has remained unknown. The E3 ligase COP1 is a central negative regulator for photomorphogenesis under visible light and far-red light. Intriguingly,COP1 plays positive roles in UVR8-mediated UV-b photomorphogenesis. UV-b signaling is essentially abolished in cop1 mutant alleles with unknown mechanisms. Through GR-UVR8 transgenic lines,we demonstrated that UVR8 is active in nucleus for UV-b photomorphogenesis. Moreover,the UV-btriggered UVR8 nuclear accumulation is absent in cop1 mutants. Our results emphasize the importance of nuclear-localized UVR8 and highlight a previously unknown activity of COP1 in mediating UVR8 nuclear accumulation in response to UV-b.

关键词： UV-b photomorphogenesis UVR8 COP1 nuclear accumulation

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World Journal of Virology 2024年第2期13卷 96-106页

作者： Nanda Chhavi Geetika Srivastava mariya Waseem Abhishek Yadav Surender Singh Rajani Singh Amit Goel Department of Paediatrics Era’s Lucknow Medical CollegeLucknow 226003Uttar PradeshIndia Medical Consultant National Disease Control ProgramNational Health MissionLucknow 226003Uttar PradeshIndia Department of Hepatology Sanjay Gandhi Postgraduate Institute of Medical SciencesLucknow 226014Uttar PradeshIndia

bACKGROUND birth-dose(Hep-bD)followed by three additional doses(Hep-b3)of hepatitis b virus(HbV)vaccine are key to eliminating HbV by ***,Hep-bD and Hep-b3 coverage in our country is *** To studied the parent’s knowledge and awareness about HbV infection,its prevention,consequences and *** Parents of 6 months to 8 years old children were interviewed to assess their knowledge&awareness about hepatitis b,its transmission,prevention,illness caused by this,and *** close-ended questions were admini-stered,and responses were recorded as‘yes’,‘no’,or‘not sure’.HbV knowledge score was calculated based on the sum of correct *** correct response scored one point and incorrect,missing or‘not sure’responses received no *** data are presented as number(%)and numerical data are expressed as *** were compared using Chi2 tests and level of significance was kept as Pb3 vaccinated.94.3%,87.5%,and 29.2%parents knew about polio,tetanus,and hepatitis b ***,41.2%,15.8%,and 23%parents knew about hepatitis b transmission,consequences of infection,and prevention *** 7.6%parents knew about three-dose schedule of hepatitis b *** 23%parents believed that vaccine could prevent HbV,15.7%knew that HbV affects *** of Hep-b3 vaccinated children were significantly more aware about HbV than the parents of unvaccinated children(Pbout hepatitis b is *** Increasing knowledge/awareness about HbV among parents may improve Hep-b3 vaccination coverage.

关键词： Hepatitis b Viral hepatitis Cirrhosis Hepatocellular carcinoma Hepatotropic viruses Transfusion transmitted infection Mother to child transmission