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Limb Muscle Hemodynamics and Arterial Distensibility Depend on Atmospheric Pressure in Hypertensive Men

Biomedical and Environmental Sciences 2013年第4期26卷 284-294页

作者： Vladimir n.MELnIKOV sergey G.KRIVOSCHEKOV Tamara G.KOMLYAGInA Svetlana Y.RECHKInA nathan S.COnSEDInE Institute of Physiology Siberian Branch of the Russian Academy of Medical SciencesNovosibirsk630117Russia Sanatorium "El'tsovka " NovosibirskRussia Department of Psychological Medicine University of AucklandNew Zealand

Objective To verify whether peripheral blood circulation and arterial wall distensibility are influenced by atmospheric pressure （AtPr） and to examine if their association is dependent on age and/or sex. Methods Associations among natural AtPr levels （on the examination day as well as 1 and 2 days prior）, limb muscle hemodynamics, and distensibility of conduit arteries were retrospectively examined in an observational study of 276 untreated patients with primary moderate hypertension （mean age 56.4 years, 194 men）. Forearm and calf circulations at rest and 3 min after ischemia were measured by venous occlusion plethysmography. Compliance of the brachial and shank arteries was assessed by oscillometry. Results After adjustment for age, degree of hypertension, and season, correlation and multiple resression analyses revealed a season-independent but age-dependent direct correlation between the stiffness of limb arteries and AtPr levels on the examination day in men, but not women. The association weakened with the degree of hypertension, disappeared with age, and was more evident in the arms than in the legs. Conclusion Parameters of arterial wall distensibility in adult hypertensive men are susceptible to AtPr changes within the usually observed limits （730-770 mmHg）. It is proposed that reduction of arterial wall barometric responsiveness in women and aging men is a likely mechanism underlying their meteosensitivity.

关键词： Atmospheric pressure Arterial stiffness Compliance Venous circulation Age-dependence Sex difference Season

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Polysaccharides as initiators of nucleic acid polymerization

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American Journal of Molecular Biology 2014年第1期4卷 20-25页

作者： Aleksander n. Zimnitskii sergey A. Bashkatov Aleksey V. Chemeris Renat S. Yamidanov Vadym n. Urazbaev Bashkir State University Ufa Russia Biochemistry and Genetics Institute Russian Academy of Sciences Ufa Russia Institute of Organic Chemistry Russian Academy of Sciences Ufa Russia Research and Production Association “Plazan” Moscow Russia

Quantum-chemical calculations and in vitro experiments have demonstrated that polysaccharides are able to adsorb mononucleotides due to the formation of hydrogen bonds. The subsequent dehydration of polysaccharide-nucleotide complexes in the physiologically acceptable temperature range results in the creation of “correct” DnA polymers that are “recognized” by the specific DnA-polymerases. DnA fragments abiogenically formed on polysaccharides vary in size and are characterized by a relatively “simple”, most probably, tandem structure. This research developed our previous concept of template-based polysaccharide synthesis with the participation of DnA tandem repeats (glycotranscription concept) making it possible to assume the existence of reverse glycotranscription in biological systems. Future research in the direction that we outlined experimentally may lead to a revolutionary approach in modern molecular biology—glycogenomics.

关键词： Polysaccharides nucleic Acids Polymerization Complementarity PCR

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The role of polysaccharides in the molecular evolution of biopolymers

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natural Science 2014年第2期6卷 59-70页

作者： Aleksander n. Zimnitskii sergey A. Bashkatov Vadym n. Urazbaev Aleksey V. Chemeris Renat S. Yamidanov Bashkir State University Ufa Russia Biochemistry and Genetics Institute of Russian Academy of Sciences Ufa Russia Institute of Organic Chemistry Russian Academy of Sciences Ufa Russia Research and Production Association “Plazan” Moscow Russia

The empirical (biochemical, the PCR method) and computational (quantum-chemical, PM3) methods have shown the ability of polysaccharides to catalyze the polymerization of amino acids and nucleotides within the physiologically acceptable temperature range. The possibility of nucleotide aminoacylation in the presence of polysaccharides has been established. The suggestion has been made that abiogenic aminoacylation of nucleotides by polysaccharides served as the prototype of the original aminoacylpre-tRnA-synthetase activity and subsequently determined the formation of the modern mechanism of genetic information transfer via three biopolymer types—nucleic acids, proteins and polysaccharides.

关键词： Molecular Evolution Aminoacylation Polysaccharides Amino Acids nucleic Acids Guantum Chemistry PCR

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同胞侵犯对猞猁幼仔行为的影响(英文)

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动物学报 2008年第1期54卷 12-19页

作者： Anastasiya AnTOnEVICH sergey nAIDEnKO A.n.Severtsov Institute of Ecology and Evolution RAS Leninsky pr .33 Moscow119071 Russia

研究了非自由生活的4窝11只猞猁幼仔的玩耍行为、亲和及入侵关系的变化。观察到36 -57日龄幼仔的同胞打斗行为,这些打斗减少了这些幼仔之间游戏性接触的频次。这个"打斗期"与游戏行为和食性的变化同步发生。打斗后,幼仔游戏性接触的非... 详细信息

研究了非自由生活的4窝11只猞猁幼仔的玩耍行为、亲和及入侵关系的变化。观察到36 -57日龄幼仔的同胞打斗行为,这些打斗减少了这些幼仔之间游戏性接触的频次。这个"打斗期"与游戏行为和食性的变化同步发生。打斗后,幼仔游戏性接触的非对称性以及同胞之间的偏爱更加清楚。这些打斗导致了不同窝的幼仔之间等级结构的建立。

关键词：猞猁社会行为个体发育同胞关系

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Some Features of neural networks as nonlinearly Parameterized Models of Unknown Systems Using an Online Learning Algorithm

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Journal of Applied Mathematics and Physics 2018年第1期6卷 247-263页

作者： Leonid S. Zhiteckii Valerii n. Azarskov sergey A. nikolaienko Klaudia Yu. Solovchuk Department of Intelligent Automatic Systems International Centre of Information Technologies and Systems Institute of Cybernetics Kiev Ukraine Aircraft Control Systems Department National Aviation University Kiev Ukraine

This paper deals with deriving the properties of updated neural network model that is exploited to identify an unknown nonlinear system via the standard gradient learning algorithm. The convergence of this algorithm for online training the three-layer neural networks in stochastic environment is studied. A special case where an unknown nonlinearity can exactly be approximated by some neural network with a nonlinear activation function for its output layer is considered. To analyze the asymptotic behavior of the learning processes, the so-called Lyapunov-like approach is utilized. As the Lyapunov function, the expected value of the square of approximation error depending on network parameters is chosen. Within this approach, sufficient conditions guaranteeing the convergence of learning algorithm with probability 1 are derived. Simulation results are presented to support the theoretical analysis.

关键词： neural network nonlinear Model Online Learning Algorithm Lyapunov Func-tion Probabilistic Convergence

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GABAA-Coupled Cl-/ HCO3--ATPase from Plasma Membrane of the Rat Brain: Role of HCO3-in the Enzyme Activation

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Advances in Enzyme Research 2015年第1期3卷 9-18页

作者： sergey A. Menzikov Margarita n. Karpova Lada V. Kuznetsova natalya Y. Klishina Federal State Scientific Institution “Research Institute of General Pathology and Pathophysiology” Moscow Russia

This work examines the influence of Cl- (2.5 - 125 mM) and HCO3- (2 - 30 mM) on the Cl-/HCO3- - ATPase complex of the neuronal membrane and this enzyme is a Cl--pump that is coupled to GABAA receptors. The greatest (44%) activating effect on the enzyme is found with HCO3- (20 - 30 mM), while the maximum activity occurs in the presence of a ratio of ~25 mM HCO3- /~5mM Cl-. Blockers of the GABAA receptor, namely bicuculline (10 - 50 μM) and picrotoxin (50 - 100 μM), inhibit this anion activation, whereas the HCO3- -ATPase activity is not sensitive to these ligands. Autoradiographic analysis of the spectrum of the partially purified enzyme phosphorylated with [γ-32P]ATP allowed us to distinguish three major 32P-labeled protein whose molecular weight are about 57, 53, and 48 kDa. In the presence of 5 mM Cl-/25mM HCO3- and 100 μM picrotoxin, the intensity of the phosphorylation of bands significantly decreased, thereby confirming the assumption about coupled of binding sites for anions and GABAA-ergic ligands. It was suggested scheme of Cl--transport through the plasma membrane by utilizing neuronal Cl-/ -HCO3- ATPase in the low (5 mM) Cl- and high (25 mM) HCO3- concentrations. The data demonstrated for the first time that the GABAA-coupled Cl-/ HCO3- -ATPase from rat brain neuronal membranes is maximally activated at a Cl-/HCO3- ratio of 1:5 and it remains stable at high concentrations of substrate and buffer.

关键词： Rat Brain Plasma Membrane Mg2+-ATPase Chloride Bicarbonate Mg2+-ATP Picrotoxin Bicuculline Autoradiography Molecular Weight Subunits

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Structural transitions in Pb(In_(1/2)nb_(1/2))O_(3) under pressure

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Journal of Advanced Dielectrics 2015年第4期5卷 42-52页

作者： Muhtar Ahart Maddury Somayazulu Seiji Kojima naohiko Yasuda sergey Prosandeev Russell J.Hemley Geophysical Laboratory Carnegie Institution of Washington 5251 Broad Branch Rd.NWWashington DC 20015USA Institute of Materials Science University of Tsukuba TsukubaIbaraki 305-8573Japan Electrical and Electronic Engineering Department Faculty of Engineering Gifu UniversityGifu 501-1193Japan Physics Department and Institute for nanoscience and Engineering University of Arkansas Fayetteville Arkansas 72701USA Department of Physics Research Institute of Physics Southern Federal UniversityRostov on Don 344090Russia

Room-temperature Raman scattering and x-ray difraction measurements together with first principles calculations were employed to invetigate the behavior of disordered Pb(In_(1/2)nb_(1/2))O_(3)(PIn)under pressure up to *** spectra show broad bands but a peak near the 380cm^(-1) increases its intensity with *** linewidth of the band at 550cm^(-1) also increases with pressure,while two of the Raman peaks merge above *** 16 GPa,we observe additional splitting of the band at 50cm^(-1).The pressure evolution of the diffraction patterns for PIn shows obvious Bragg peaks splitting above 16GPa;consistent with a symmetry lowering *** transition at 0.5 GPa is identified as a pseudo-cubic to orthorhombic(Pbam)structural change whereas the transition at 16GPa is istructure and associated with changes in linear compresibility and octahedral titling,and the transition at 30 GPa is associated to an orthorhombic to monoclinic ***-principles calculations indicate that the Pbam structure is ground state with antiferrodisdortion consistent with experiment.

关键词： Relaxor frrolectrics high-pressure structural phase transition

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非线性常微分方程的解在无穷处的渐近行为（英文）

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华东师范大学学报（自然科学版） 2016年第6期 94-101,118页

作者： sergey Prokhozhiy 倪明康维特伯斯克州立大学数学系华东师范大学数学系上海200241

本文研究了非线性常微分方程v"-c_1(v^n)'-c_2v^p=0解的渐近行为.考虑了所有参数间的相互关系.确立了第一渐近项以及在第二渐近项下存在的诸多情形.同时研究了正负值下的柯西问题.

关键词：常微分方程渐近行为非线性

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The Mg-carbonate-Fe interaction:Implication for the fate of subducted carbonates and formation of diamond in the lower mantle

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Geoscience Frontiers 2019年第4期10卷 1449-1458页

作者： naira S.Martirosyan Konstantin D. Litasov sergey S. Lobanov Alexander F. Goncharov Anton Shatskiy Hiroaki Ohfuji Vitali Prakapenka Sobolev Institute of Geology and Mineralogy Russian Academy of ScienceKoptyuga ave.3Novosibirsk630090Russia Geophysical Laboratory Carnegie Institution for ScienceWashingtonDC20015USA novosibirsk State University Pirogova st.2Novosibirsk630090Russia Geodynamic Research Center Ehime UniversityMatsuyamaEhime790-8577Japan Center for Advanced Radiation Sources University of ChicagoChicagoIL60637USA

The fate of subducted carbonates in the lower mantle and at the core-mantle boundary was modelled via experiments in the MgCO3-Fe^0 system at 70-150 GPa and 800-2600 Kin a laser-heated diamond anvil *** in situ synchrotro n X-ray diffraction and ex situ transmission electron microscopy we show that the reduction of Mg-carbonate can be exemplified by:6 MgCO3+19 Fe=8 FeO+10(Mg0.6Fe^0.4)O+Fe7 C3+3 *** presented results suggest that the interaction of carbonates with Fe^0 or Fe^0-bearing rocks can produce Fe-carbide and diamond,which can accumulate in the D"region,depending on its carbon to Fe *** to the sluggish kinetics of the transformation,diamond can remain metastable at the core-mantle boundary(CMB)unless it is in a direct contact with *** addition,it can be remobilized by redox melting accompanying the generation of mantle plumes.

关键词： Deep carbon cycle Carbonate Carbide High pressure Redox reaction

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Economic Dispatch Considering Hourly Capacity Allocation with a Variable Renewable and Hydro-Based Generation Portfolio

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Energy and Power Engineering 2022年第10期14卷 594-614页

作者： Roney n. Vitorino Dorel S. Ramos Karen Tapia-Ahumada sergey Paltsev John M. Reilly Energy Research Office Rio de Janeiro Brazil Polytechnic School University of Sao Paulo Sao Paulo Brazil Massachusetts Institute of Technology Cambridge USA

The objective of this paper is to assess an economic dispatch considering a power system portfolio, which includes predominant amount of hydro power and increasing quantities of intermittent renewables in relation to the total electric capacity. With growing importance of intermittent wind and solar generation taking part into power systems worldwide, there is need for greater chronological resolution to estimate the flexibility of the power system to offer firm capacity. In this way, a linear optimization model operating hourly is developed to calculate the minimum power system cost, while stablishing the capacity allocation to meet the projected load throughout one-year simulation, as an estimation of how the hourly economic dispatch impacts the scheduling of generators belonging to a power system with this portfolio composition. A central focus is how to operate the available hydro capacity to back up intermittent renewables, evaluating the physical hydro operating constraints, monthly energy balance and maximum power availability. A case study was simulated based on the Brazil’s power system configuration, showing that existing hydro capacity provide hourly flexibility to back-up intermittent renewables, potentially saving 1.2 Billion R$, about 3.6% of total system cost referred to 2019. It is worthwhile to realize that the developed methodology can be employed to other power systems with similar capacity portfolio structure for the purpose of calculating its optimum allocation for a specified region and target year.

关键词： Economic Dispatch Energy Planning Operation Flexibility Power System Transmission System Variable Renewable Energy

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