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Dissipation of Solitary Waves in Aluminum with Grain Boundary

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Journal of Materials Science & Technology 1998年第5期14卷 475-477页

作者： Psakhie, S.G. Zolnikov, K.P. Saraev, D.Yu. institute of Strength Physics and Materials Science Russian Academy of Sciences Siberian Branch Akademicheskii pr.2/1 634021 Tomsk Russian Federation

The behavior of passing solitary waves through the region of grain boundary has been investigated on the basis of the molecular dynamics method. It has been shown that solitary waves initiated by compression and shear loading have a different interaction with the grain boundary region. The possibilities of using solitary waves for nondestructive testing of materials, in particular, for testing the quality of coatings, for testing of accumulation of microdamages, etc. have been noted. (Edited author abstract) 5 Refs.

关键词： Aluminum

Many-body Interatomic Potentials for Computer Simulation of Physical Processes in Metals and Alloys

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Journal of Materials Science & Technology 1998年第5期14卷 429-433页

作者： Kuznetsov, V.M. Rudenskii, G.E. Kadyrov, R.I. Kaminskii, P. institute of Strength Physics and Material Science Russian Academy of Sciences Siberian Branch Academicheskii av. 2/1 634048 Tomsk Russian Federation

A model of binding forces in metals and alloys, based on the density functional theory and accounted effects of the many-body interactions, was proposed. The developed method can be easily applied for study of metals and alloys by the molecular dynamics simulation. The potentials of interatomic interactions have been found by the proposed method and applied for calculations of equation of state, elastic moduli and phonon dispersion in metals Ni, Al, and alloys NiAl, Ni//3Al. Results of the calculations are in good agreement with known experimental data both for pure metals and alloys. (Edited author abstract) 16 Refs.

关键词： Nickel

Alien species of mammals and their impact on natural ecosystems in the biosphere reserves of Russia

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Integrative Zoology 2008年第2期3卷 83-94页

作者： Valery M.NERONOV Ludmila A.KHLYAP Vladimir V.BOBROV Andrey A.WARSHAVSKY A.N.Severtsov institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia

The paper analyses the results of a survey of 37 russian biosphere reserves using questionnaires concerning thepresence of alien species of mammals, their pathways of penetration, and their impacts on protected *** penetration of alien mammals into terrestrial ecosystems of Russia is extensive, both in places with maximumhuman environmental impact (inhabited areas and agricultural lands) and in biosphere reserves with minimal humanimpact. There are 62 mammal species registered as alien in russian ecosystems and they account for 22% of theterrestrial mammal fauna of Russia. The percentage of alien species in biosphere reserves is 32.6% at most. In mostregions, Castor fiber, Ondatra zibethicus, Nyctereutes procyonoides, Canis familiaris, Neovison vison and Susscrofa are very dangerous, and both Castor fiber and Sus scrofa can have environment-forming impacts.

关键词： alien species biosphere reserves invasions mammals(Mammalia) Russia.

Nonlinear Young’s Modulus of New Red Sandstone:Experimental Studies

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Acta Mechanica Solida Sinica 2021年第6期34卷 989-999页

作者： Evgenii Riabokon Vladimir Poplygin Mikhail Turbakov Evgenii Kozhevnikov Dmitrii Kobiakov Mikhail Guzev Marian Wiercigroch Centre for Applied dynamics Research School of EngineeringUniversity of AberdeenAberdeenUK Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPermRussia institute of Applied Mathematics Far Eastern Branch of the Russian Academy of SciencesVladivostokRussia

Young’s modulus of New Red Sandstone was investigated experimentally to gain insight into its nonlinear nature.A large experimental programme was carried out by applying a controllable quasi-static and dynamic uniaxial loading to 286 dry sandstone samples of four different *** static and dynamic tests,similar to those aiming at determining the uniaxial compressive strength,were conducted using the state-of-the-art experimental facilities at the University of Aberdeen including a custom-built small experimental rig for inducing a dynamic uniaxial compressive load via a piezoelectric *** obtained results have confirmed a complex nature of Young’s modulus of ***,under a harmonic dynamic loading,it shows strongly nonlinear behaviour,which is hardening and softening with respect to frequency and amplitude of the dynamic loading,respectively.

关键词： Sandstone Young’s modulus Static and dynamic loading Experiments Stress and strain Nonlinearity

Drosophila melanogaster brain invasion pathogenic Wolbachia in central nervous system of the fly

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Insect Science 2016年第2期23卷 253-264页

作者： Anton Strunov Elena Kiseleva institute of Cytology and Genetics Siberian Branch of the Russian Academy of Sciences Prospekt Lavrentyeva 10 Novosibirsk 630090Russia

The pathogenic Wolbachia strain wMelPop rapidly over-replicates in the brain, muscles, and retina of Drosophila melanogaster, causing severe tissue degeneration and premature death of the host. The unique features of this endosymbiont make it an excellent tool to be used for biological control of insects, pests, and vectors of human diseases. To follow the dynamics of bacterial morphology and titer in the nerve cells we used transmission electron microscopy of 3-d-old female brains. The neurons and glial cells from central brain of the fly had different Wolbachia titers ranging from single bacteria to large accumulations, tearing cell apart and invading extracellular space. The neuropile regions of the brain were free of wMelPop. Wolbaehia tightly interacted with host cell organelles and underwent several morphological changes in nerve cells. Based on different morphological types of bacteria described we propose for the first time a scheme of wMelPop dynamics within the somatic tissue of the host.

关键词： bacterial morphology dynamics brain Drosophila melanogaster electronmicroscopy pathogenic endosymbiont Wolbachia strain wMelPop

Breeding versus survival:proximate causes of abrupt population decline under environmental change in a desert rodent,the midday gerbil(Meriones meridianus)

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Integrative Zoology 2019年第4期14卷 366-375页

作者： Andrey TCHABOVSKY Ludmila SAVINETSKAYA Elena SURKOVA Laboratory for Population Ecology A.N.Severtsov Institute of Ecology and EvolutionRussian Academy of SciencesMoscowRussia

Studying abrupt ecological shifts under gradual environmental change caused,in particular,by human activity is important for understanding the fundamental aspects and underlying mechanisms of ecological *** of the rare well-documented examples of an abrupt ecological shift is the delayed step transition of the population of a desert rodent,the midday gerbil(Meriones meridianus),from high-abundance(1994-2002)to low-abundance(2003-2017)*** was in response to landscape transformation from desert to steppe caused by the drastic reduction of livestock in the rangelands of southern Russia after the collapse of the USSR in the early *** this study,we tested whether demographic parameters were correlated with the observed abrupt downward population *** found that reproductive activity(the percentage of breeding females,the number of litters,fecundity and the number of young recruited per female)showed no trend over time and did not differ between periods of high and low *** contrast,the adult sex ratio(SR=males:females)decreased significantly with time and was as much as twice more female-biased for the low-abundance population ***,SR was not related to any reproductive parameter,including the percentage of breeding fe*** conclude that proximate reasons for an abrupt population decline in *** are not associated with the changes in breeding patterns or mate limitation caused by the Allee effect but relate to the increased mortality as a result of the desert landscape being fragmented by *** mortality is expected to be higher for males as the mobile and dispersing sex.

关键词： demography landscape change rangelands reproduction threshold population dynamics

Flare evolution and polarization changes in fine structures of solar radio emission in the 2013 April 11 event

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Research in Astronomy and Astrophysics 2016年第2期16卷 69-80页

作者： Gennady Chernov Robert Sych Bao-Lin Tan Yi-Hua Yan Cheng-Ming Tan Qi-Jun Fu Marian Karlicky Valery Fomichev Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China Pushkov institute of Terrestrial Magnetism Ionosphere and Radio Wave PropagationRussian Academy of Sciences(IZMIRAN)TroitskMoscow region142190Russia Yunnan Observatories Chinese Academy of SciencesKunming 650011China institute of Solar-Terrestrial Physics Russian Academy of SciencesSiberian BranchIrkutsk 664033Russia Astronomical institute of the academy of sciences of the Czech Republic Ondrejov 15165Czech Republic

The measurement of positions and sizes of radio sources in observations is important for un- derstanding of the flare evolution. For the first time, solar radio spectral fine structures in an M6.5 flare that occurred on 2013 April 11 were observed simultaneously by several radio instruments at four different observatories： Chinese Solar Broadband Radio Spectrometer at Huairou （SBRS/Huairou）, Ondrejov Radio Spectrograph in the Czech Republic （ORSC/Ondrejov）, Badary Broadband Microwave Spectropolarimeter （BMS/Irkutsk）, and spectrograph/IZMIRAN （Moscow, Troitsk）. The fine structures included microwave zebra patterns （ZPs）, fast pulsations and fiber bursts. They were observed during the flare brightening lo- cated at the tops of a loop arcade as shown in images taken by the extreme ultraviolet （EUV） telescope onboard NASA＇s satellite Solar dynamics Observatory （SDO）. The flare occurred at 06：58-07：26 UT in solar active region NOAA 11719 located close to the solar disk center. ZPs appeared near high frequency boundaries of the pulsations, and their spectra observed in Huairou and Ondrejov agreed with each other in terms of details. At the beginning of the flare＇s impulsive phase, a strong narrowband ZP burst occurred with a moderate left-handed circular polarization. Then a series of pulsations and ZPs were observed in almost unpolarized emission. After 07：00 UT a ZP appeared with a moderate right-handed polarization. In the flare decay phase （at about 07：25 UT）, ZPs and fiber bursts become strongly right-hand polarized. BMS/Irkutsk spectral observations indicated that the background emission showed a left-handed circular polarization （similar to SBRS/Huairou spectra around 3 GHz）. However, the fine structure appeared in the right-handed polarization. The dynamics of the polarization was associated with the motion of the flare ex- citer, which was observed in EUV images at 171 A and 131 A by the SDO Atmospheric Imaging Assembly （AIA）. Combining magnetograms observed by t

关键词： Sun activity -- Sun flares -- Sun particle emission -- Sun radio radiation -- zebra-pattern

Identification of genes involved in the formation of soluble dietary fiber in winter rye grain and their expression in cultivars with different viscosities of wholemeal water extract

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The Crop Journal 2022年第2期10卷 532-549页

作者： Liudmila V.Kozlova Alsu R.Nazipova Oleg V.Gorshkov Liliya F.Gilmullina Olga V.Sautkina Natalia V.Petrova Oksana I.Trofimova Sergey N.Ponomarev Mira L Ponomareva Tatyana A.Gorshkova Kazan institute of Biochemistry and Biophysics Federal Research CenterKazan Scientific Center of the Russian Academy of Sciences420111 KazanRussia Tatar Scientific Research institute of Agriculture Federal Research CenterKazan Scientific Center of the Russian Academy of Sciences420059 KazanRussia

The grain of rye(Secale cereale L.) used for baking contains a large amount of non-starch polysaccharides,making it an excellent component of functional foods. But rye grain intended for alcohol production and forage use should have a reduced content of these polysaccharides. A comprehensive parameter that can predict the best field of application for winter rye grain is the viscosity of its wholemeal water ***, our understanding of the genetic background underlying this key trait and associated features of rye grain is poor. By analyzing six russian winter rye cultivars, we identified the most contrasting forms and characterized the peculiarities of their water-soluble carbohydrates capable of influencing the viscosity of water extracts. Then, using phylogenetic and transcriptomic analyses, we identified in the rye genome many genes encoding putative glycosyltransferases and glycosylhydrolases responsible for the synthesis and degradation of arabinoxylans, mixed-linkage glucans, cellulose, and some other polysaccharides. We determined the dynamics of m RNA abundance for these genes at three stages of kernel development. Comparisons of gene expression levels in two contrasting cultivars revealed specific members of multigene families that may serve as promising targets for manipulating non-starch polysaccharide content in rye grain. High-viscosity cultivars were characterized by up-regulation of many glycosyltransferases involved in the biosynthesis of arabinoxylans and other cell-wall polysaccharides,whereas low-viscosity cultivars showed up-regulation of several genes encoding polysaccharidedegrading enzymes.

关键词： Rye(Secale cereale) Kernel development Arabinoxylan Mixed-linkage glucan Viscosity

Ectomycorrhiza of Larix sibirica Ledeb. along the gradients of main ecological factors and elevation at the Northern and Subpolar Urals

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Journal of Mountain Science 2018年第12期15卷 2603-2613页

作者： SIZONENKO Tatyana Alexandrovna DUBROVSKIY Yuriy Alexandrovich institute of Biology of Komi Scientific Centre of the Ural Branch of the russian academy of sciences Russia SyktyvkarKommunistieheskaya str28Syktyvkar167000Russian Federation

Siberian larch(Larix sibirica Ledeb.) forests cover the largest areas in the Eurasian boreal zone, but there are insufficient data on its root system including the structure and functional traits of ectomycorrhizas(EM). The aim of this research is to find out if the morphological parameters of Larix sibirica EMs responded to the changes in elevation and main ecological factors(soil humidity, soil richness, soil acidity and habitat illumination). Using light microscopy, we studied EM diameter, root diameter, mantle width, and mantle volume share, share of tannin cells layers, EM density and EM length of Larix sibirica in two main types of plant communities along the elevation gradient at the Northern and Subpolar Urals. Differences in the environment were traced using phytoindication approach and the Ellenberg ecological scales. All the studied traits depend on the elevation and studied ecological factors. The diversity of fungal mantles is low, and the proportion of unstructured and pseudoparenchymatous mantles is high in response to the deterioration of the humidity, soil nitrogen content and acidity at higher-altitude habitats. Results of EM quantitative parameters measurements confirmed this pattern. We found a decline in the EM linear dimensions accompanied by a compensatory growth of the EM density with the raised elevation and the deterioration of environmental conditions.

关键词： Ectomycorrhiza Larix sibirica Anatomy Fungal mantles diversity Elevation Urals