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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

Dynamic magnetic hysteresis in a liquid suspension of acicular maghemite particles

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Particuology 2009年第6期7卷 451-458页

作者： Bronislav E.Kashevsky sergey B.Kashevsky Igor v.Prokhorov A.v.Luikov Heat and Mass Transfer Institute Belarus Academy of SciencesP.Brovka str.15Minsk 220072Belarus

This paper presents theoretical and experimental studies on the magnetodynamics and energy absorption in a dilute suspension of small ferromagnetic particles with magnetic hysteresis and mechanical mobility in an AC magnetic field. Experiments with 0.1% suspensions of acicular particles of gamma ferric oxide in solid and liquid matrices, subjected to a 430 Hz magnetic field with an intensity of up to 1200 Oe, revealed important role of particle mobility. The main qualitative and quantitative features of the phenomenon are in agreement with a model of joint magneto-mechanical dynamics of particles with a chain-of-spheres mode of incoherent magnetic reversal.

关键词： High-coercive magnetic particles Magnetic suspensions Dynamic magnetic hysteresis

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

Potential role of peripheral blood mononuclear cell' s mitochondrial respiratory dysfunction in heart failure severity prediction in patients with cardioverter-defibrillator implantation indications

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Journal of Geriatric Cardiology 2024年第10期21卷 981-991页

作者： Tariel A Atabekov sergey N Krivolapov Mikhail S Khlynin viacheslav A Korepanov Tatiana Yu Rebrova Elvira F Muslimova sergey A Afanasiev Roman E Batalov sergey v Popov Cardiology Research Institute Tomsk National Research Medical CenterRussian Academy of SciencesTomskRussia

Background It has been reported that the mitochondrial respiratory dysfunction (MRD) is important mechanisms affecting the heart failure (HF) *** sought to evaluate the potential role of MRD of peripheral blood mononuclear cells (PBMC) in HF severity prediction in patients with cardioverter-defibrillator implantation *** In this single-center study patients with HF of New York Heart Association (NYHA) Ⅰ-Ⅲ functional class (FC) and cardioverter-defibrillator implantation indications underwent transthoracic echocardiography (TTE) and MRD assessment using *** respiration rate (MRR) indicators (pyruvate+malate+adenosine diphosphate;succinate+adenosine diphosphate;pyruvate+malate–adenosine diphosphate[v4.1];succinate–adenosine diphosphate) were *** between HF NYHA FC,TTE and MRR indicators were *** on our data,we developed a risk model regarding HF *** Of 53 (100.0%) HF patients,33 (62.3%) had mild exercise intolerance (1stgroup) and 20 (37.7%) had moderate-to-severe exercise intolerance (2ndgroup).Patients with mild exercise intolerance were likely to have a higher v4.1(Pvalues.v4.1was independently associated with moderate-to-severe exercise intolerance in univariate and multivariate logistic regression (OR=0.932,95%CI:0.891–0.975,Pverity of HF is associated with PBMC mitochondrial respiratory dysfunction in patients with cardioverter-defibrillator implantation *** HF severity risk model including v4.1parameters is able to distinguish patients with mild and moderate-to-severe exercise *** investigations of their predictive significance are warranted.

关键词： severity patients indications

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

Photoluminescence,structural and antibacterial properties of co-dopedβ-Ca_(3)(PO_(4))_(2)-type phosphates Ca_(8)CuRE(PO_(4))_(7)(RE=Eu-Er)

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Journal of Rare Earths 2024年第9期42卷 1658-1668,I0002页

作者： Ivan v.Nikiforov Ekaterina v.Iliin Bogdan I.Lazoryak sergey M.Aksenov Pavel v.Slukin Dina v.Deyneko Department of Chemistry Lomonosov Moscow State University119991MoscowRussia Laboratory of Arctic Mineralogy and Material Sciences Kola Science CentreRussian Academy of Sciences184209ApatityRussia Geological Institute Kola Science CentreRussian Academy of Sciences184209ApatityRussia State Scientific Center of Applied Microbiology and Biotechnology of Rospotrebnadzor 24 Block A142279ObolenskRussia

Novel Ca_(8)CuRE(PO_(4))_(7)where RE^(3+)=Eu^(3+),Tb^(3+),Dy^(3+),Ho^(3+)and Er^(3+)were synthesized by a solid-state method in *** structures of the samples were characterized by powder X-ray diffraction using Rietveld refinement to determine the occupation of crystal *** samples are found to have a centrosymmetric structure with space group R3c,as shown by dielectric *** synthesized Ca_(8)CuRE(PO_(4))_(7)samples have multifunctional *** Cu^(2+)ions provide antibacterial properties,while the rare earth elements ions exhibit luminescence properties,and theβ-Ca_3(PO_(4))_(2)-type host is *** photoluminescence properties of RE^(3+)ions were studied and compared with other simmilar Ca_(8)MRE(PO_(4))_(7)phosphates,where M is a divalent *** photoluminescence intensity quenching in terms of energy transfer from RE^(3+)to Cu^(2+)is *** bioactive properties were studied in relation to antibacterial activity against *** and *** syntesized Ca_(8)CuRE(PO_(4))_(7)samples demonstrate very high and stable inhibition of bacteria *** correlation between crystal structure and properties is *** combining multiple approaches to the directio nal design of such materials,several important properties within a single chemical compound to achieve biovisualization and bioactive properties simultaneously can be combined.

关键词： β-Ca_(3)(PO_(4))_(2) Whitlockite-type structure Bioactive phosphates TCP Photoluminescence Rare earths