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isotopic Composition of Atmospheric Precipitation in the Cis-Ural Region

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Journal of Earth Science 2022年第3期33卷 831-838页

作者： Alena S.Kazantseva olga i.Kadebskaya Yuri V.Dublyansky Mining institute of the Ural Branch of the Russian Academy of Sciences PermRussia institute of Geology University of InnsbruckInnsbruckAustria

Using the Global Network of isotopes in Precipitation(GNiP)method at three stations in the Cis-Ural region(iskor,Perm,and Kungur),the monitoring results of the isotope composition of atmospheric precipitation conducted in 2016-2019 are *** lines of meteoric waters were obtained for each station and for the Cis-Ural region as a *** latitudinal zoning of changes in isotope parameters from north to south in the Cis-Ural region is noted,which is related to meteorological *** northern regions are characterized by isotopically light values compared to the southern ***,the correlation relationship between the isotopic compositions of atmospheric precipitation and meteorological parameters at each station is *** analysis data show that about 50%-90%of variations in the isotopic composition of precipitation within the annual cycle are determined by the air *** the same time,the amount of precipitation shows a relationship between the average strength and the isotopic composition of precipitation for a series of observations at Kungur Station;for a series of observations at iskor and Perm stations,there is no *** in the relationship with meteorological data are explained by different sources of moisture introduction to the station and,accordingly,the formation of the isotopic composition of *** flow of moisture is controlled by the transfer of air masses in different directions,the formation of cyclones and ***,for the northern part of the region during the year is characterized by the predominance of cyclones,whereas for the southern-anticyclones.

关键词： precipitation isotopic composition Cis-Ural region correlation relationship Spear-man’s correlation coefficient

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Nonconservative mechanical systems with nonholonomic constraints

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Science China(Physics,Mechanics & Astronomy) 2012年第8期55卷 1475-1484页

作者： KRUPKOV olga Department of Mathematics Faculty of Science The University of Ostrava 30. dubna 22 701 03 Ostrava Czech Republic Department of Mathematics and Statistics La Trobe University Melbourne Victoria 3086 Australia

A geometric setting for generally nonconservative mechanical systems on fibred manifolds is proposed. Emphasis is put on an explicit formulation of nonholonomic mechanics when an unconstrained Lagrangian system moves in a generally non-potential force field depending on time, positions and velocities, and the constraints are nonholonomic, not necessarily linear in velocities. Equations of motion, and the corresponding Harniltonian equations in intrinsic form are given. Regularity conditions are found and a nonholonomic Legendre transformation is proposed, leading to a canonical form of the nonholonomic Hamiltonian equations for nonconservative systems.

关键词： nonconservative mechanical systems equations of motion Hamiltonian equations nonholonomic constraints Chetaevequations Hamiltonian equations for nonconservative nonholonomic systems

Paleoclimate Study of Mountain Ecosystems by Multiple Group Biological Analysis

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Journal of Mountain Science 2011年第1期8卷 24-36页

作者： Marina SKRYPNiKOVA olga USPENSKAYA olga KHOKHLOVA Dokuchaev Soil Science institute of Russian Academy of Agricultural Sciences Pyzhevsky Lane7Moscow109017Russia Vegetable institute of Russian Academy of Agricultural Sciences h.500v.VereaRamenskii distMoscow region140153Russia institute of Physical Chemical and Biological Problems in Soil Science of RASUlitsa Institutskaya2PushchinoMoscow region142290Russia

Methodological problems of climatic reconstruction for different periods of Holocene are discussed on the basis of a multiple group biological analysis on peat-sapropel sediments. The possibility of biological analysis is exemplified by the paleoclimatic reconstruction for Carpathian and Altai Mountain ranges. For the ＂Skolevsky Beskidy＂ national park of Carpaty the paleoclimatic scenarios have been drown up aiming at the more precise definition of climatic conditions for the period of mass mountain slope terracing. The stability of terrace systems of various designs in the current climatic conditions has been assessed. it is shown that during periods of humid climate the terraces, whose designs have been focused on drainage, were built. in periods of dry and warm climate the terrace systems capable of accumulating water were built. Both these types of terrace systems are destroyed in nowadays. Only those terrace systems are stable which were adjusted by their builders to contrast variations of precipitation. For Western Altais the paleoclimatic scenario has been done to forecast the safety of the Bronze Age kurgans （burial earth mounds） with permafrost inside the construction. in the Altay region during the Holocene it has revealed two periods of sharp cooling, the peaks of which occurred in the intervals 4500- 4300 and 2500-2300 years pronounced climatic drying ago, and two periods of 4900-4700 and 130-70 years ago. Depletion of the algae composition in the layer corresponding to the last period of drying climate indicates a very sharp change in the parameters of moisture and turning the lake into a dry swamp. Periods of cold weather may have contributed to the formation of special ritual traditions of the Sakan tribes that require the frozen ground to bury the dead. The later climate fluctuations identified have not affected the safety of permafrost in burial mounds constructed in the V-iii cc BC.

关键词： Climatic reconstruction Complex group biological analysis of peat-sapropel sediments Paleopedology Soil evolution Holocene

Deciphering tau-related dementia using human iPSC lines: electrophysiological perspectives of future studies

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Neural Regeneration Research 2022年第12期17卷 2672-2674页

作者： olga Kopach Queen Square institute of Neurology University College LondonLondonUK

To date,no disease-modifying treatment or cure is available for *** disorder is becoming more common as the global population *** has been over several decades of extensive research focusing on how the pathology develops and progresses causing memory loss,brain damage,and eventually death-it provides the field with a deep understanding of what proteins,peptides,and signaling molecules contribute to neurodegeneration at the molecular,genetic,and cellular *** problem is,however,that there is a wide range of dementia types.A given disease can span heterogeneous clinical syndromes with diverse symptomatology,no matter whether it is“senile dementia”or an early-onset form;moreover,it encompasses the mixed features of many syndromes in later stages of the disease.

关键词： senile pathology eventually

Searching for the brightest stars in galaxies outside the Local Group

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Research in Astronomy and Astrophysics 2021年第4期21卷 264-270页

作者： Nikolay Tikhonov olga Galazutdinova olga Sholukhova Antoniya Valcheva Petko Nedialkov olga Merkulova Special Astrophysical Observatory Nizhnij ArkhyzKarachai-Cherkessian RepublicRussia 369167 Department of Astronomy Sofia University1504 Sofia15 Tsar Osvoboditel Blvd.SofiaBulgaria Astronomical institute St.Petersburg State UniversityUniversitetskii pr.28St.Petersburg198504 Russia

This paper introduces a technique for searching for bright massive stars in galaxies beyond the Local *** search for massive stars,we processed the results of stellar photometry from the Hubble Space Telescope(HST)images using the DAOPHOT and DOLPHOT *** results of such searches are demonstrated with examples of the galaxies DDO 68,M94 and NGC *** the galaxy DDO 68,the LBV star changes its brightness,and massive stars in M94 can be identified by excess in the Ha *** the galaxy NGC 1672,we measure the distance for the first time by the TRGB method,which enabled determining the luminosities of the brightest stars,likely hypergiants,in the young star formation *** far,we have performed stellar photometry on HST images of 320 northern sky galaxies located at a distance less than 12 *** allowed us to identify 53 galaxies with probable *** photometric and spectral observations of these galaxies are planned to search for massive stars.

关键词： stars:massive stars:variables:LBV galaxies:individual:M94 DDO 68 NGC 1672

Factors associated with trabecular bone score in postmenopausal women with type 2 diabetes and normal bone mineral density

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World Journal of Diabetes 2022年第7期13卷 553-565页

作者： olga N Fazullina Anton i Korbut Vadim V Klimontov Laboratory of Endocrinology Research Institute of Clinical and Experimental Lymphology-Branch of the Institute of Cytology and GeneticsSiberian Branch of Russian Academy of SciencesNovosibirsk 630060Russia

BACKGROUND Osteoporosis and type 2 diabetes(T2D)have been recognized as a widespread comorbidity leading to excess mortality and an enormous healthcare *** T2D,bone mineral density(BMD)may underestimate the risk of low-energy fractures as bone quality is *** was hypothesized that a decrease in the trabecular bone score(TBS),a parameter assessing bone microarchitecture,may be an early marker of impaired bone health in women with *** To identify clinical and body composition parameters that affect TBS in postmenopausal women with T2D and normal *** A non-interventional cross-sectional comparative study was *** eligible subjects were screened at tertiary referral *** women with T2D,aged 50-75 years,with no established risk factors for secondary osteoporosis,were ***,TBS and body composition parameters were assessed by dual-energy X-ray *** women with normal BMD,a wide range of anthropometric,general and diabetes-related clinical and laboratory parameters were evaluated as risk factors for TBS decrease using univariate and multivariate regression analysis and analysis of receiver operating characteristic(ROC)*** Three hundred twelve women were initially screened,176 of them met the inclusion criteria and underwent dual X-ray *** with reduced BMD were subsequently excluded;96 women with normal BMD were included in final *** them,43 women(44.8%)showed decreased TBS values(≤1.31).Women with TBS≤1.31 were taller and had a lower body mass index(BMi)when compared to those with normal TBS(Р=0.008 and P=0.007 respectively).No significant differences in HbA1c,renal function,calcium,phosphorus,alkaline phosphatase,PTH and 25(ОН)D levels were *** a model of multivariate linear regression analysis,TBS was positively associated with gynoid fat mass,whereas the height and androgen fat mass were associated negatively(all Pin a multiple logistic regres

关键词： Diabetes Osteoporosis Bone mineral density Trabecular bone score Obesity Body composition

U-Blacks Mineralization in Sandstone Uranium Deposits

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Journal of Earth Science 2022年第2期33卷 308-316页

作者： olga A.Doynikova institute of Ore Deposits Geology PetrographyMineralogy and Geochemistry Russian Academy of ScienceMoscow 119017Russia

Ores of infiltration sandstone-hosted uranium deposits in the sedimentary cover are ubiquitous composed of dispersed soot powder mineralization of black,brownish-black *** studies of such loose U-ores by analytical transmission electron microscopy(ATEM)proved their polymineral *** blacks are composed by at least three different U-mineral forms:oxide(uraninite),silicate(coffinite)and phosphate(ningyoite)which are present in various proportions of ore *** high dispersed friable uranium formations are difficult to diagnose by traditional mineralogical methods(optical,XRD,iR and X-ray spectroscopy,etc.)which analyze total sample composition(phases mixture);their results characterize the dominant sample phase,omitting both sharply subordinate and X-ray amorphous *** research results are based on ATEM methods(SAED+EDS),which are optimal for crystallochemical diagnostics in the mineralogical study of such uranium *** article presents the diagnostic characteristics under electron microscope(EM)of uranous minerals from different sandstone deposits with their origin being discussed.

关键词： uranous minerals uraninite coffinite ningyoite biogenic nature U-deposit ore deposit geology

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iNiTiAL VALUE TECHNiQUES FOR THE HELMHOLTZ AND MAXWELL EQUATiONS

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Journal of Computational Mathematics 2007年第3期25卷 368-373页

作者： Frank Natterer olga Klyubina Department of Mathematics University of MünsterGermany

We study the initial value problem of the Helmholtz equation with spatially variable wave number. We show that it can be stabilized by suppressing the evanescent waves. The stabilized Helmholtz equation can be solved numerically by a marching scheme combined with FFT. The resulting algorithm has complexity n^2 log n on a n x n grid. We demonstrate the efficacy of the method by numerical examples with caustics. For the Maxwell equation the same treatment is possible after reducing it to a second order system. We show how the method can be used for inverse problems arising in acoustic tomography and microwave imaging.

关键词： Stability of elliptic initial value problems Parabolic wave equation inverseproblems in acoustics and electromagnetics.

Novel method for the preparation of Cs-containing FAU（Y） catalysts for aniline methylation

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 70-76页

作者： olga A. Ponomareva Polina A. Shaposhnik Marina Vo Belova Boris A. Kolozhvari irina i. ivanova Department of Chemistry Lomonosov Moscow State University Moscow 119991 Russia A.V. Topchiev institute of Petrochemical Synthesis Moscow Russia

Cs-containing FAU（Y）-type zeolite catalysts were prepared by conventional and novel ion exchange procedures followed by incipient wetness impregnation with CsOH. The novel ion exchange procedure involved hydrothermal treatment of NaY zeolite in aqueous solution of CsCl at 140-200 ℃ for 6-24 h. The samples were characterized by low-temperature nitrogen adsorption, X-ray fluorescence analysis, X-ray powder diffraction, scanning electron microscopy, 23Na, 27Al and 133Cs magic angle spinning nuclear magnetic resonance, CO2 and NH3-Temperature programmed desorption. The results show that hydrothermal treatment at 200 ℃ allows to obtain higher degrees of ion-exchange （up to 83%） with respect to conventional method giving maximum 66%- 69%. Catalytic properties of Cs-containing FAU（Y） were studied in aniline methylation. The yield of Nomethylani- line is shown to correlate with catalyst＇s basicity. The best catalyst performance was achieved over the catalyst with the highest ion-exchange degree impregnated with CsOH. The selectivity to N-methylaniline over this catalyst reached 96.4%.

关键词： FAU(Y) zeolite ion exchange with cesium aniline alkylation N-methylaniline