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Integrative Zoology 2014年第4期9卷 471-480页

作者： Gennady G.BOESKOROv olga R.POTAPOvA Eugeny N.MASHCHENKO Albert v.PROTOPOPOv Tatyana v.KUZNETSOvA Larry AGENBROAD Alexey N.TIKHONOv Diamond and Precious Metal Geology Institute Siberian Branch of Russian Academy of SciencesYakutskRussia The Mammoth Site of Hot Springs Museum Hot SpringsSouth DakotaUSA Paleontological Institute Russian Academy of SciencesMoscowRussia Department of the Mammoth Fauna Studies Academy of Sciences of the Sakha(Yakutia)Republic YakutskRussia M.v.Lomonosov Moscow State University MoscowRussia Zoological Institute Russian Academy of SciencesSt.PetersburgRussia

The frozen bodies of a young woolly mammoth(Mammuthus primigenius),a wild horse(Equus sp.)and a steppe bison(Bison priscus)were recently found in the northern Yakutia(northeastern Siberia).All specimens have preserved bones,skin and soft *** the woolly mammoth and the Pleistocene horse were represented by partial frozen bodies,the steppe bison body was recovered in an absolutely complete *** specimens were found frozen in the permafrost,with some of the tissues *** wild horse and steppe bison are of Holocene age,and the mammoth is of Late Pleistocene age.

关键词： bison horse mammoth mummy Siberia

Continuous wafer-scale graphene on cubic-SiC（O01）

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Nano Research 2013年第8期6卷 562-570页

作者： Alexander N. Chaika olga v. Molodtsova Alexei A. Zakharov Dmitry Marchenko Jaime Sanchez-Barrig Andrei varykhalov Igor v. Shvets victor Yu. Aristov Institute of Solid State Physics RAS Chemogolovka Moscow District 142432 Russia Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) School of Physics Trinity College Dublin 2 Ireland HASYLAB at DESY D-22607 Hamburg Germany MAX-lab Lund University Box 118 22100 Lund Sweden Helmholtz-Zentrum Berlin für Materialien und Energie D- 12489 Berlin Germany

The atomic and electronic structure of graphene synthesized on commercially available cubic-SiC（001）/Si（001） wafers have been studied by low energy electron microscopy （LEEM）, scanning tunneling microscopy （STM）, low energy electron diffraction （LEED）, and angle resolved photoelectron spectroscopy （ARPES）. LEEM and STM data prove the wafer-scale continuity and uniform thickness of the graphene overlayer on SIC（001）. LEEM, STM and ARPES studies reveal that the graphene overlayer on SIC（001） consists of only a few monolayers with physical properties of quasi-freestanding graphene. Atomically resolved STM and micro-LEED data show that the top graphene layer consists of nanometer-sized domains with four different lattice orientations connected through the 〈110〉-directed boundaries. ARPES studies reveal the typical electron spectrum of graphene with the Dirac points close to the Fermi level. Thus, the use of technologically relevant SiC（001）/Si（001） wafers for graphene fabrication repre-sents a realistic way of bridging the gap between the outstanding properties of graphene and their applications.

关键词： graphene cubic-SiC(001) STM ARPES LEEM LEED

Application of pan-sharpening algorithm for correlative multimodal imaging using AFM-IR

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npj Computational Materials 2019年第1期5卷 714-722页

作者： Nikolay Borodinov Natasha Bilkey Marcus Foston Anton v.Ievlev Alex Belianinov Stephen Jesse Rama K.vasudevan Sergei v.Kalinin olga S.Ovchinnikova Center for Nanophase Materials Science Oak Ridge National LaboratoryOak RidgeTN 37831USA Department of Energy Environmental&Chemical EngineeringWashington University in St.LouisOne Brookings DriveSt.LouisMO 63130USA

The coupling of atomic force microscopy with infrared spectroscopy(AFM-IR)offers the unique capability to characterize the local chemical and physical makeup of a broad variety of materials with nanoscale ***,in order to fully utilize the measurement capability of AFM-IR,a three-dimensional dataset(2D map with a spectroscopic dimension)needs to be acquired,which is prohibitively time-consuming at the same spatial resolution of a regular AFM *** this paper,we provide a new approach to process spectral AFM-IR data based on a multicomponent pan-sharpening *** approach requires only a low spatial resolution spectral and a limited number of high spatial resolution single wavenumber chemical maps to generate a high spatial resolution hyperspectral image,greatly reducing data acquisition *** a result,we are able to generate highresolution maps of component distribution,produce chemical maps at any wavenumber available in the spectral range,and perform correlative analysis of the physical and chemical properties of the *** highlight our approach via imaging of plant cell walls as a model system and showcase the interplay between mechanical stiffness of the sample and its chemical *** believe our pan-sharpening approach can be more generally applied to different material classes to enable deeper understanding of that structure-property relationship at the nanoscale.

关键词： utilize modal walls

Population dynamics of Amur tigers(Panthera tigris altaica)in Sikhote-Alin Biosphere Zapovednik:1966–2012

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Integrative Zoology 2015年第4期10卷 315-328页

作者： Dale G.MIQUELLE evgeny N.SMIRNOv olga Yu.ZAUMYSLOvA Svetlana v.SOUTYRINA Douglas H.JOHNSON Wildlife Conservation Society BronxNew YorkUSA Sikhote-Alin Biosphere Zapovednik TerneiPrimorskii KraiRussia USGS Northern Prairie Wildlife Research Center Saint PaulMinnesotaUSA

In 2010,the world’s tiger(Panthera tigris)range countries agreed to the goal of doubling tiger numbers over 12 years,but whether such an increase is biologically feasible has not been ***-term monitoring of tigers in Sikhote-Alin Biosphere Zapovednik(SABZ),Russia provided an opportunity to determine growth rates of a recovering population.A 41-year growth phase was followed by a rapid decline in tiger *** growth rates during the growth phase averaged 4.6%,beginning near 10%in the earliest years but quickly dropping below 5%.Sex ratio(females per male)mirrored growth rates,declining as population size *** rapid decline from 2009 to 2012 appeared to be tied to multiple factors,including poaching,severe winters and *** indicators of this population are similar to those of Bengal tiger populations,suggesting that growth rates may be *** results suggest that,first,tiger populations likely in general grow slowly:3–5%yearly increases are realistic and larger growth rates are likely only when populations are highly depressed,mortality rates are low and prey populations are high relative to numbers of adult ***,while more research is needed,it should not be assumed that tiger populations with high prey densities will necessarily grow more quickly than populations with low prey ***,while growth is slow,decline can be ***,because declines can happen so quickly,there is a constant need to monitor populations and be ready to respond with appropriate and timely conservation interventions if tiger populations are to remain ***,an average annual growth rate across all tiger populations of 6%,required to reach the Global Tiger Initiative’s goal of doubling tiger numbers in 12 years,is a noble but unlikely scenario.

关键词： Amur tiger growth rates population dynamics

Selective footprints and genes relevant to cold adaptation and other phenotypic traits are unscrambled in the genomes of divergently selected chicken breeds

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Journal of Animal Science and Biotechnology 2023年第3期14卷 887-907页

作者： Michael N.Romanov Alexandra S.Abdelmanova vladimir I.Fisinin Elena A.Gladyr Natalia A.volkova olga A.Koshkina Andrey N.Rodionov Anastasia N.vetokh Igor v.Gusev Dmitry v.Anshakov olga I.Stanishevskaya Arsen v.Dotsev Darren K.Griffin Natalia A.Zinovieva L.K.Ernst Federal Research Centre for Animal Husbandry DubrovitsyPodolskMoscow RegionRussia School of Biosciences University of KentCanterburyUK Federal State Budget Scientific Institution Federal Research Centre“All-Russian Poultry Research and Technological Institute”of the Russian Academy of Sciences Sergiev PosadMoscow RegionRussia Breeding and Genetic Centre“Zagorsk Experimental Breeding Farm”–Branch of the Federal Research Centre“All-Russian Poultry Research and Technological Institute”of the Russian Academy of Sciences Sergiev PosadMoscow RegionRussia Russian Research Institute of Farm Animal Genetics and Breeding–Branch of the L.K.Ernst Federal Research Centre for Animal Husbandry St.PetersburgRussia

Background The genomes of worldwide poultry breeds divergently selected for performance and other phenotypic traits may also be affected by,and formed due to,past and current admixture *** to diverse environments,including acclimation to harsh climatic conditions,has also left selection footprints in breed *** Using the Chicken 50K_CobbCons SNP chip,we genotyped four divergently selected breeds:two aboriginal,cold tolerant Ushanka and Orloff Mille Fleur,one egg-type Russian White subjected to artificial selection for cold tolerance,and one meat-type White *** of selective sweeps were determined in the studied breeds using three methods:(1)assessment of runs of homozygosity islands,(2)F_(ST) based population differential analysis,and(3)haplotype differentiation *** regions of true selection signatures were identified by two or more methods or in two or more *** these regions,we detected 540 prioritized candidate genes supplemented them with those that occurred in one breed using one statistic and were suggested in other *** them,SOX5,ME3,ZNF536,WWP1,RIPK2,OSGIN2,DECR1,TPO,PPARGC1A,BDNF,MSTN,and beta-keratin genes can be especially mentioned as candidates for cold *** factors may be involved in regulating some of these important genes(e.g.,TPO and BDNF).Conclusion Based on a genome-wide scan,our findings can help dissect the genetic architecture underlying various phenotypic traits in chicken *** include genes representing the sine qua non for adaptation to harsh *** tolerance in acclimated chicken breeds may be developed following one of few specific gene expression mechanisms or more than one overlapping response known in cold-exposed individuals,and this warrants further investigation.

关键词： Acclimation Adaptation Chicken breeds Cold tolerance Divergent selection Genetic diversity Genomewide scan Phenotypic traits Selective sweeps

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

Identification and Preliminary Characterization of a New Chemical Affecting Glucosyltransferase Activities Involved in Plant Cell Wall Biosynthesis

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Molecular Plant 2008年第6期1卷 977-989页

作者： olga Zabotina Erik Maim Georgia Drakakaki vincent Bulone Natasha Raikhel Institute for Integrative Genome Biology Center for Plant Cell Biology and Department of Botany and Plant Sciences University of California Riverside CA92521 USA School of Biotechnology Royal Institute of Technology (KTH) AlbaNova University Center Stockholm SE-106 91 Sweden Present address: Department of Biochemistry Biophysics and Molecular Biology Iowa State University Ames IA 50014 USA

Chemical genetics as a part of chemical genomics is a powerful and fast developing approach to dissect biological processes that may be difficult to characterize using conventional genetics because of gene redundancy or lethality and, in the case of polysaccharide biosynthesis, plant flexibility. Polysaccharide synthetic enzymes are located in two main compartments--the Golgi apparatus and plasma membrane-and can be studied in vitro using membrane fractions. Here, we first developed a high-throughput assay that allowed the screening of a library of chemicals with a potential effect on glycosyltransferase activities. Out of the 4800 chemicals screened for their effect on Golgi glucosyltransferases, 66 compounds from the primary screen had an effect on carbohydrate biosynthesis. Ten of these compounds were confirmed to inhibit glucose incorporation after a second screen. One compound exhibiting a strong inhibition effect （ID 6240780 named chemical A） was selected and further studied. It reversibly inhibits the transfer of glucose from UDP-glucose by Golgi membranes, but activates the plasma membrane-bound callose synthase. The inhibition effect is dependent on the chemical structure of the compound, which does not affect endomembrane morphology of the plant cells, but causes changes in cell wall composition. Chemical A represents a novel drug with a great potential for the study of the mechanisms of Golgi and plasma membrane-bound glucosyltransferases.

关键词： cell walls callose synthase chemical screening and identification glycosyltransferase Golgi plasma membrane

Effect of vertical electromagnetic stirring on solute distribution in billet continuous casting process

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Journal of Iron and Steel Research International 2022年第1期29卷 132-143页

作者： Tao Wang En-gang Wang Yves Delannoy Yves Fautrelle olga Budenkova Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang 110004LiaoningChina CNRS Grenoble INPSIMAPUniversité Grenoble AlpesGrenoble 38000France School of Metallurgy Northeastern UniversityShenyang 110004LiaoningChina CNRS Grenoble INPLEGIUniversité Grenoble AlpesGrenoble 38000France

A volume averaged columnar solidification model,which couples the flow,temperature and solute concentration fields,is applied to simulate experimental continuous casting cases with and without vertical electromagnetic stirring(v-EMS).The calculated distribution of magnetic induction intensity and final macrosegregation maps are consistent with the experimental *** results reveal that the v-EMS promotes longitudinal melt flow,accelerates heat dissipation and solidification and finally reduces the central segregation of ***,when v-EMS is applied,the solute distribution becomes asymmetric because the melt flow shows opposite directions between the near and far sides from *** obvious positive segregation band is observed at about 1/4 width of the billet near the stirrer in both calculated and experimental *** position and degree of such positive segregation could be affected by installation height of stirrer,as demonstrated by additional simulation cases.

关键词： vertical electromagnetic stirring Macrosegregation volume averaged method Continuous casting

Impact of Natural Oil-Based Recycled Polyols on Properties of Cast Polyurethanes

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Journal of Renewable Materials 2018年第7期6卷 697-706页

作者： Hynek Beneš Aleksandra Paruzel JiříHodan olga Trhlíková Institute of Macromolecular Chemistry AS CR v.v.i.Heyrovsky Sq.216206 Prague 6Czech Republic

In this study, castor oil, rapeseed oil and medium chain triglycerides of coconut oil, were transesterified bymeans of 2-ethyl-2-hydroxymethyl-1,3-propanediol (trimethylolpropane) and consequently used to convertpolycarbonate waste from end-of-life vehicles into liquid polyols. The prepared recycled polyols, composeduniquely of renewable and recycled components, had a hydroxyl number of ca. 250 mg KOH·g−1. They weresuccessfully applied as 100% replacement of a virgin polyol for preparation of solid crosslinked polyurethanes(PU) by solvent-free casting. The produced rigid cast PU exhibited the main transition temperature rangingfrom 44°C to 53°C, the hardness value from 46 to 61 Shore D and the beneficial low water absorption (0.4-0.5wt.%). The PU network structure was highly influenced by the presence of aromatic structures ofpolycarbonate-units and fatty acid compositions. A suitable selection of natural oil thus enabled to adjustthermo-mechanical properties and promote excellent optical transparency of the produced PU.

关键词： Natural oil cast polyurethane bio-based polycarbonate waste recycling

Giga- and terahertz-range nanoemitter based on peapod structure

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Nano Research 2015年第8期8卷 2595-2602页

作者： Michail M. Slepchenkov Anna S. Kolesnikova George v. Savostyanov1 Igor S. Nefedov Ilya v. Anoshkin Albert G. Nasibulin olga E. Glukhova Department of Physics Saratov State University Saratov 410012 Russia Department of Radio Science and Engineering Aalto University Aalto P.O. Box 13000 Finland kolkovo Institute of Science and Technology Skolkovo 143025 Russia

We propose a theoretical model of a nanoemitter for giga- and terahertz-range waves. The model is based on a peapod structure comprising a carbon nanotube with chiral indices （10, 10）. Three encapsulated and partially polymerized fuUerene C60 molecules and a positively charged C60 fullerene are trapped inside the nanotube. The motion of the charged fullerene and the radiation frequency were controlled using an external electric field. Stable terahertz radiation at a frequency of 0.36 THz was produced at 300 K with an external electrical field of 10 v/μm. Stable radiation in the gigahertz range was observed at 50 K with an electric field below 10 v/m. A theoretical simulation was performed using the tight-binding molecular dynamics method with a description of the van der Waals interaction by the Morse potential. The system described by the theoretical model was experimentally observed.

关键词： fullerenes nanotubes electronics simulations molecular modeling