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Age of maturation and behavioral tactics in male yellow ground squirrel Spermophilus fulvus during mating season

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Current Zoology 2014年第6期60卷 700-711页

作者： Nina A. vASILIEvA Ekaterina v. PAvLOvA sergey v. NAIDENKO Andrey v.TCHABOvSKY A.N. Severtsov Institute of Ecology and Evolution Russian Academy of Sciences 33 Leninsky pr. Moscow 119071 Russia

Life-history theory predicts that in hibemators age of maturation is related positively to body size and negatively to the duration of active season aboveground. Yellow souslik is a large-sized ground squirrel with long hibernation, which suggests late maturation. We used four-year field observations of marked individuals to determine the age of maturation in males through analysis of age-dependent variation in body size, mass, androgen status, timing of spring emergence, ranging patterns and social behavior during the mating season. Yearling males were smaller, lighter, had lower level of fecal testosterone, emerged later and had smaller home ranges than older males. Social activity and the number of females encountered did not differ between age classes. After the second hibernation none of the studied parameters varied with age. Cluster analysis revealed two behavioral tactics：＂active＂ males （adults only） emerged earlier, ranged more widely, initiated more contacts, encountered more females and were heavier than ＂passive＂ males （both yearling and adult）. Thus, males of S. fulvus reached adult size and matured after two hibernations, which is relatively fast for such a big species with short active period. Indirect evidence for copulations and high variation among yearlings in all parameters suggest that some of them might successfully compete with adults. Active tactic of wandering and searching for females is energetically costly, and probably only adult males in good physical condition can afford it, whereas passive tactic of residing is energy saving and good for adults in poor condition and for yearlings that are continuing to grow.

关键词： Age of maturation Mating system Reproductive tactics Ground squirrel Spermophilusfulvus

Modern problems of aircraft aerodynamics

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Advances in Aerodynamics 2019年第1期1卷 145-159页

作者： sergey L.Chernyshev sergey v.Lyapunov Andrey v.Wolkov Department of Aerodynamics Central Aerohydrodynamic Institute named after Prof.N.EZhukovsky(TsAGI)140180Zhukovsky str.1ZhukovskyRussia

The article represents the discussion of several separate directions of investigations,which are performed by TsAGI flight vehicles aerodynamics specialists at the *** are some major trends of classical layout of route aircraft and also peculiarities of some prospective flight *** there are some hypersonic vehicles aerodynamics questions examined along with problems of creation of civil supersonic transport *** is a description given for well-known and some newer methods of flow control for drag reduction.

关键词： Aircraft aerodynamics Hypersonic vehicles aerodynamics Civil supersonic transport aircraft Sonic boom

Energy stored in nanoscale water capillary bridges formed between chemically heterogeneous surfaces with circular patches

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Chinese Physics B 2020年第11期29卷 44-51页

作者： Bin-Ze Tang Xue-Jia Yu sergey v.Buldyrev Nicolas Giovambattista Li-Mei Xu International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Department of Physics Yeshiva University500 West 185th StreetNew YorkNY 10033United States Department of Physics Brooklyn College of the City University of New YorkBrooklynNew York 11210United States Ph.D.Programs in Chemistry and Physics The Graduate Center of the City University of New YorkNew YorkNY 10016United States Collaborative Innovation Center of Quantum Matter Beijing 100871China

The formation of nanoscale water capillary bridges(WCBs) between chemically heterogeneous(patchy) surfaces plays an important role in different scientific and engineering applications, including nanolithography, colloidal aggregation, and bioinspired adhesion. However, the properties of WCB of nanoscale dimensions remain unclear. Using molecular dynamics simulations, we investigate the geometrical and thermodynamic properties of WCB confined between chemically heterogeneous surfaces composed of circular hydrophilic patches on a hydrophobic background. We find that macroscopic capillary theory provides a good description of the WCB geometry and forces induced by the WCB on the confining surfaces even in the case of surface patches with diameters of only 4 nm. Upon stretching, the WCB contact angle changes from hydrophobic-like values(θ > 90°) to hydrophilic-like values(θ vant amounts of energy EPand explore how the walls patch geometry can be improved in order to maximize EP. Our findings show that nanoscale WCB can, in principle, be exploited for the design of clean energy storage devices as well as actuators that respond to changes in relative humidity. The present results can also be of crucial importance for the understanding of water transport in nanoporous media and nanoscale engineering systems.

关键词： water capillary bridge energy density morphology transition hydrophilicity

Zircon U-Pb Geochronology Recorded Late Cretaceous Fluid Activation in the Central Aldan Gold Ore District, Aldan Shield, Russia: First Data

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Journal of Earth Science 2020年第3期31卷 481-491页

作者： vasilii I.Leontev sergey G.Skublov Nadezhda v.Shatova Alexey v.Berezin Faculty of Geological Prospecting Saint Petersburg Mining University199106 St.PetersburgRussia Institute of Precambrian Geology and Geochronology of Russian Academy of Sciences 199034 St.PetersburgRussia Karpinsky Russian Geological Research Institute 199106 St.PetersburgRussia Institute of Earth Science St.Petersburg State University199034 St.PetersburgRussia

The gold mineralization in the Central Aldan ore district is genetically related to potassic calc-alkaline and alkaline magmatism dated at 115–150 *** objective of this study is to establish the age of hydrothermal processes that accompanied the formation of Au-Te mineralization at the Samolazovsky *** on the isotope-geochemical study of zircons from quartz-feldspar metasomatic rocks of the deposit,the granitoids and charnokites of the Nimnyr Complex(1900–1960 Ma)at the contact with the Yukhta monzonite-syenite massif(~127 Ma)were *** U-Pb dating was performed on a SHRIMP-II ion microprobe,and rare-earth and trace elements analyses of zircon were carried out in the same craters by secondary-ion mass spectrometry on a Cameca IMS-4f ion *** is revealed that the studied zircons have heterogeneous structures:dark core and lighter rim,which differ greatly in isotope-geochemical *** rims are cut by a network of fractures,extending into the central part of zircon *** rims yield a subconcordant age of 1937±24 Ma,with an average total REE content of 550 ppm,which corresponds to the formation age of the Nimnyr *** zircon cores yield a discordant age of 83±11 Ma and are characterized by a higher total REE content(~1812 ppm),as well as higher contents of U and non-formula elements(Ca,Sr,and Y)with respect to rims,due to the effect of fluid on *** the limited number of zircon grains,the additional geochronological study of zircons from syenites of the ore-bearing Ryabinovy Massif has revealed the presence of two distinct age clusters:~125–138 and 76–83Ма.The older ages of zircons from syenites are typical for the Central Aldan ore *** now,there is still no explanation for an age range(76–83 Ma)of single zircon grains from ore-bearing syenites of the Ryabinovy *** obtained data suggest that the processes of activation(the effect of fluid)within the Central Aldan ore district continued unt

关键词： U-Pb geochronology REE geochemistry zircon Samolazovskoe Deposit Ryabinovoe Deposit Aldan Shield

Characterization and Electrochemical Properties of Nanostructured Zr-Doped Anatase TiO_2 Tubes Synthesized by Sol–Gel Template Route

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Journal of Materials Science & Technology 2017年第6期33卷 527-534页

作者： Denis P.Opra sergey v.Gnedenkov sergey L.Sinebryukhov Elena I.voit Alexander A.Sokolov Evgeny B.Modin Anatoly B.Podgorbunsky Yury v.Sushkov veniamin v.Zheleznov Institute of Chemistry Far Eastern Branch of Russian Academy of Sciences Far Eastern Federal University National Research Centre "Kurchatov Institute"

A series of nanostructured Zr-doped anatase TiO_2 tubes with the Zr/Ti molar ratio of 0.01, 0.02, 0.03, and0.09 were prepared by a sol–gel technology on a carbon fiber template. The electrochemical performance of Zr-doped anatase TiO_2 as anodes for rechargeable lithium batteries was investigated and compared with undoped titania. Tests represented that after 35-fold charge/discharge cycling at C/10 the reversible capacity of Zr-doped titania（Zr/Ti = 0.03） reaches 135 m A h g^（-1）, while the capacity of undoped titania（Zr/Ti = 0） yielded only 50 m A h g^（-1）. Based on the results of the physicochemical investigation, three reasons of improving electrochemical performance of Zr-doped titania were suggested. According to the scanning electron microscopy and transmission electron microscopy, Zr^（4＋） doping induces a decrease in nanoparticle size, which facilitates the Li＋diffusion. The Raman investigations show the more open structure of Zr-doped TiO_2 as compared to undoped titania due to changing of the unit cell parameters, that significantly affects on the reversibility of the insertion/extraction process. The electrochemical impedance spectroscopy results indicate that substitution of Zr^（4＋） for Ti^（4＋） into anatase TiO_2 has favorable effects on the conductivity.

关键词： Li-ion batteries Anatase titania Nanostructured materials Sol–gel template process Doping Electrochemical performance

Geochemistry of Thermal Waters of Continental Margin of Far East of Russia

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 276-284页

作者： Ivan v. BRAGIN Georgy A. CHELNOKOv Oleg v. CHUDAEv Natalia A. KHARITONOvA sergey v. vYSOTSKIY Far East Geological Institute Russian Academy of SciencesVladivostok690022 Russia Moscow State University Moscow119991 Russia Far East Federal University Vladivostok690922 Russia

Studied waters belong to warm （T=30-50℃）, alkaline （pH=8.9-9.3）, low mineralized （TDS〈235 mg/l） Na-HCO3 or Na-SO4-HCO3 thermal waters with high content of SiO2 （up to 81 mg/1） and F （up to 3.9 mg/l）, occur on modern volcano-tectonic rejuvenated areas of Eastern Sikhote-Alin orogenic belt. Low 3He concentration as well as N2/O2 and N2/Ar ratios exclude influence of deep mantle fluid. New rare earth element data constrain our understanding of water-rock interaction occurring in the water source region. Meteoric origin of waters is proved by stable isotope values varying from -71%o to -136.1‰ and from -10.8‰ to -18.8%o for δ^2H and δ^18O respectively. REE patterns reflect high pH, resultfing from water-rock interaction and oxidative conditions. Calculations of deep aquifer temperature using Na-K and quartz geothermometers show 116.8-131.1℃ and 82.2-125.8℃ respectively. Presence of deep faults both with abnormal thermal gradient （-45- 50 K/km） define unique geochemical shape of thermal waters of Sikhote-Alin, area, where no present volcanic activity is registered.

关键词： thermal waters water-rock interaction stable water isotopes rare earth elements in thermal waters

Genotoxic Potential of Copper Oxide Nanoparticles in the Bivalve Mollusk Mytilus trossulus

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Journal of Ocean University of China 2017年第2期16卷 339-345页

作者： victor P.Chelomin valentina v.Slobodskova Maksim Zakhartsev sergey Kukla Laboratory of Marine Ecotoxicology V.I.Ilichev Pacific Oceanological Institute of the Far East Branch of Russian Academy of SciencesVladivostok 600041Russia The Far Eastern Federal University School of Natural SciencesVladivostok 600091Russia University of Hohenheim Stuttgart 70599Germany

Copper oxide nanoparticles(CuO-NPs) are among the most widely used metal oxide nanoparticles,which increases the chance of their being released into the marine *** the applications of these particles have increased in recent years,their potential impact on the health of marine biota has also ***,the toxicological effects of these NPs in the marine environment are poorly *** the present study,the DNA damaging potential of CuO-NPs in the marine eastern mussel Mytilus trossulus was evaluated and compared to that of dissolved copper *** was assessed by the single cell gel electrophoresis(comet) assay in mussel gill and digestive gland *** results showed that copper in both forms(CuO-NPs and dissolved copper) was accumulated to different extents in mussel *** mussel exposed to the dissolved copper attained higher concentrations of copper in the gills than in the digestive *** contrast to these results,it was found that CuO-NPs could induce much higher copper accumulation in the digestive gland than in the gills.A clear and statistically significant increase in DNA damage was found in both tissues of the Cu-exposed group compared to the control *** results indicated that the CuO-NP exposure produced remarkable effects and increased DNA damage significantly in mussel gill cells *** should be noted that the digestive gland cells were prone to accumulation following CuO-NPs when compared to the gill cells,while the gill cells were more sensitive to the genotoxic effects of *** results also suggested the need for a complete risk assessment of engineered particles before its arrival in the consumer market.

关键词： CuO nanoparticles copper accumulation DNA damage genotoxicity Mytilus trossulus

An infinite-dimensional model of liquidity in financial markets

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Probability, Uncertainty and Quantitative Risk 2021年第2期6卷 117-138页

作者： sergey v Lototsky Henry Schellhorn Ran Zhao Department of Mathematics University of Southern CaliforniaLos AngelesCA 90089USA Institute of Mathematical Sciences Claremont Graduate UniversityClaremontCA 91711USA Drucker School of Management Claremont Graduate UniversityClaremontCA 91711USA

We consider a dynamic market model of liquidity where unmatched buy and sell limit orders are stored in order *** resulting net demand surface constitutes the sole input to the *** model demand using a two-parameter Brownian motion because(i)different points on the demand curve correspond to orders motivated by different information,and(ii)in general,the market price of risk equation of no-arbitrage theory has no solutions when the demand curve is driven by a finite number of factors,thus allowing for *** prove that if the driving noise is infinite-dimensional,then there is no arbitrage in the *** the equivalent martingale measure,the clearing price is a martingale,and options can be priced under the no-arbitrage *** consider several parameterizations of the model and show advantages of specifying the demand curve as a quantity that is a function of price,as opposed to price as a function of *** online appendix presents a basic empirical analysis of the model:calibration using information from actual order books,computation of option prices using Monte Carlo simulations,and comparison with observed data.

关键词： Liquidity modeling Brownian sheet Itô-Wentzell formula No-arbitrage condition Stochastic partial differential equations

Evaluation of DNA Damage in the Marine Mussel Crenomytilus grayanus as a Genotoxic Biomarker of Pollution

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Journal of Ocean University of China 2019年第1期18卷 159-164页

作者： SLOBODSKOvA valentina v. ZHURAvEL Elena v. KUKLA sergey P. CHELOMIN victor P. Laboratory of Marine Ecotoxicology V.I.Ilichev Pacific Oceanological Institute Far Eastern Branch Russian Academy of Sciences School of Natural Sciences Far Eastern Federal University

Marine pollution affects all life processes in aquatic organisms. The genotoxic effect of pollution on the mussel Crenomytilus grayanus was assessed. Bivalves were collected from the ‘clean'(vostochnaya Cove) and polluted(Nakhodka Bay) areas in the Peter the Great Bay. The degree of DNA damage in C. grayanus was determined by alkaline comet assay as mean percentage of DNA in tail, and the genetic damage index was calculated. Our results indicate that almost one-third of DNA in cells of gills and digestive gland of C. grayanus inhabiting the Nakhodka Bay had destructive changes compared to the individuals of this species from the vostochnaya Cove. This study has shown that chronic pollution of the aquatic environment causes destructive changes to DNA in gill and digestive gland cells of C. grayanus.

关键词： genotoxicity DNA comet assay Crenomytilus grayanus pollution