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Correct Interpretation of Creep Rates: A Case Study of Cu

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Journal of Materials Science & Technology 2015年第11期31卷 1065-1068页

作者： W.Blum J.Dvoák P.král P.Eisenlohr v.Sklenika Institut für Werkstoffwissenschaften University of Erlangen-Nürnberg Institute of Physics of Materials Academy of Sciences of the Czech Republic Department of Chemical Engineering and Materials Science Michigan State University

Traditionally the deformation resistance in creep is characterized by the minimum creep rate εmin and its sensitivity to stress （stress exponent n） and temperature （activation energy Q）. various values of constant n have been reported in the literature and interpreted in terms of specific mechanisms. The present case study of coarse-grained Cu at 573 k yields a stress exponent n = 9 for εmin. in tension and a relatively low activation energy. The evolution of the deformation resistance with strain at constant tensile creep load and comparison with creep in compression without fracture indicates that the tensile εmin. result from transition from uniform deformation to strain localization during fracture. This is confirmed by the results of creep in compression where fracture is suppressed. Both the tensile εmin, and the compressive creep rate at strains around 0.3 can be described using existing equations for quasi-stationary deformation containing the subgrain boundary misorientation θ as structure parameter. While in the latter case constant θ leads to monotonic increase of n with stress, the tensile nine-power-law results from variable θ, and has no simple meaning. The result of this case study means that uncritical interpretation of minimum tensile creep rates as stationary ones bears a high risk of systematic errors in the determination of creep parameters and identification of creep mechanisms.

关键词： Cu Creep Minimum creep rate Activation energy Stress exponent

Long-term survival of a patient after resection of a gastrointestinal stromal tumor arising from the pancreas

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hepatobiliary & Pancreatic Diseases International 2011年第3期10卷 330-332页

作者： Filip eka Bohumil Jon Alexander Ferko Zdeněk ubrt Dimitar H Nikolov věra Tyová Department of Surgery Faculty of Medicine and University Hospital Hradec králové Department of Field Surgery Military Health Science FacultyHradec KrálovéDefence University Brno Fingerland Department of Pathology

BACkGROUND:Gastrointestinal stromal tumors (GISTs) may arise in any part of the gastrointestinal tract;extragastrointestinal locations are extremely *** a few cases of extragastrointestinal stromal tumor arising from the pancreas were *** of the reports described a long-term follow-up of the ***:This report describes an interesting and unusual case of GIST arising from the ***:A 74-year-old female presented with a palpable abdominal *** scan showed a large mass 11×8×4 cm originating from the tail of the *** biopsy revealed a GIST predominantly with spindle cells,but some parts also contained epitheloid *** patient was treated by distal pancreatic resection with *** of the tumor showed a staining pattern characteristic of *** patient has achieved a long-term survival of five years and six months without any sign of recurrence of the ***:This is the first reported case of an extragastrointestinal stromal tumor arising from the pancreas treated surgically,with a long-term survival.

关键词： gastrointestinal stromal tumor pancreas survival

Main Directions and Recent Test Modeling Results of Lithium Capillary-Pore Systems as Plasma Facing Components

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Plasma Science and Technology 2004年第3期6卷 2291-2295页

作者： v.A.Evtikhin I.E.Lyublinski A.v.vertkov E.A.Azizov S.v.Mirnov v.B.Lazarev S.M.Sotnikov v.M.Safronov A.S.Prokhorov v.M.korzhavin FSUE "Red Star"-"Prana-Center" Co Moscow Russian FSUE TRINITI Troitsk Moscow region Russian Federation RF Ministry for Atomic Energy Moscow

At present the most promising principal solution of the divertor problemappears to be the use of liquid metals and primarily of lithium Capillary-Pore Systems (CPS) as ofplasma facing materials. A solid CPS filled with liquid lithium will have a high resistance tosurface and volume damage because of neutron radiation effects, melting, splashing and thermalstress-induced cracking in steady state and during plasma transitions to provide the normaloperation of divertor target plates and first-wall protecting elements. These materials will not bethe sources of impurities inducing an increase of Z_(eff) and they will not be collected as dust inthe divertor area and in ducts. Experiments with lithium CPS under simulating conditions of plasmadisruption on a hydrogen plasma accelerator Mk-200 [~ (10 - 15) MJ/m^2, ~ 50 μs] have beenperformed. The formation of a shielding layer of lithium plasma and the high stability of thesesystems have been shown. The new lithium limiter tests on an up-graded T-11M tokamak (plasma currentup to 100 ka, pulse length ~0.3 s) have been performed. Sorption and desorption of plasma-forminggas, lithium emission into discharge, lithium erosion, deposited power of the limiter areinvestigated in these experiments. The first results of experiments are presented.

关键词： lithium divertor plasma facing material

The Holocene environmental changes revealed from the sediments of the Yarkov sub-basin of Lake Chany,south-western Siberia

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Geoscience Frontiers 2023年第2期14卷 133-153页

作者： S.k.krivonogov A.N.Zhdanova P.A.Solotchin A.Y.kazansky v.v.Chegis Z.Liu M.Song S.v.Zhilich N.A.Rudaya X.Cao O.v.Palagushkina L.B.nazarova L.S.Syrykh Institute of Geology and Mineralogy Russian Academy of SciencesSiberian BranchNovosibirskRussia Novosibirsk State University NovosibirskRussia korkyt Ata kyzylorda University KyzylordaKazakhstan Moscow State University MoscowRussia Geological Institute Russian Academy of SciencesMoscowRussia Pushkov Institute of Terrestrial Magnetism Ionosphere and Radio Wave PropagationRussian Academy of SciencesTroitskRussia Department of Earth Sciences The University of Hong KongHong KongChina State key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’anChina Institute of Archaeology and Ethnography Russian Academy of SciencesSiberian BranchNovosibirskRussia Tomsk State University TomskRussia Alpine Paleoecology and Human Adaptation Group(ALPHA) State Key Laboratory of Tibetan Plateau Earth SystemEnvironment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijingChina volga Region Federal University KazanRussia krasnoyarsk Science Center Russian Academy of SciencesSiberian BranchKrasnoyarskRussia Herzen State Pedagogical University St.PetersburgRussia

Lake Chany is the largest endorheic lake in Siberia whose catchment is entirely on the territory of *** geographical location on the climate-sensitive boundary of wet and dry landscapes provides an opportunity to gain more knowledge about environmental changes in the West Siberian interior during the Holocene and about the evolution of the lake *** cores obtained from the Yarkov subbasin of the lake in 2008 have been comprehensively studied by a number of approaches including sedimentology and AMS dating,pollen,diatom and chironomid analyses(with statistical interpretation of the results),mineralogy of authigenic minerals and geochemistry of plant lipids(biomarker analysis.).Synthesis of new results presented here and published data provides a good justification for our hypothesis that Lake Chany is very young,no older than 3.6 ka *** that,between 9 and 3.6 ka BP,the Chany basin was a swampy landscape with a very low sedimentation rate;it could not be identified as a water *** the early lake phase,between 3.6 and 1.5 ka BP,the lake was shallow,1.2–3.5 m in depth,and it rose to its modern size,up to 6.5 m in depth,during the last *** data reveal important changes in the understanding of the history of this large endorheic lake,as before it was envisioned as a large lake with significant changes in water level since ca.14 ka *** addition to hydrology,our proxies provide updates and details of the regional vegetation and climate change since ca.4 ka BP in the WestSiberian forest-steppe and *** evolution of the Chany basin is dependent on hydroclimatic changes in a large region of southern West Siberia,we compare lake-level change and climate-change proxies from the other recently and most comprehensively studied lakes of the region.

关键词： Saline lake Multiproxy study Holocene Climate Environment West Siberia

Early Holocene climate signals from stable isotope composition of ice wedges in the Chara Basin,northern Transbaikalia,Russia

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Geoscience Frontiers 2018年第2期9卷 471-483页

作者： Yurij k.vasil’chuk Alla C.vasil’chuk Julia v.Stanilovskaya Geography and Geology Departments Lomonosov Moscow State UniversityMoscowRussia Sergeev Environmental Geoscience Institute of the Russian Academy of Sciences Russia

Stable isotope composition of syngenetic and epigenetic ice wedges, radiocarbon age, and pollen spectra of the surrounding deposits were studied during long term investigations at the "Belyi klyuch" site on the first(6-8 m height) terrace of the Chara River(720 m.a.s.l.) in northern Transbaikalia to assess climatic conditions during ice-wedge formation. It was revealed that Holocene ice wedges had been formed from 10 to 7.5 ka 14 C BP. The isotope composition(δ^(18)O, δ~2 H) of relict ice wedges is the lightest and amounts-23‰ and-185‰, correspondingly. The isotopic compositions of ice lenses from sandy loam above ice wedges are-15.7‰, and-133‰; of small ice wedge in peat and sand are-15.3‰ and-117.9‰, *** of the ice wedge isotope composition has yielded that mean winter temperatures during cold stages of Holocene optimum were lower than today, during warm stages they were close to modern ones. During the coldest stages of Holocene optimum the total annual freezing index varied from-5100 to-5700 ℃ degree days, i.e. 300-600 ℃ degree days colder than during extremely severe modern winters. The total annual thawing index varied from 1300 to 1800 ℃ degree days, which was slightly higher than modern ones.

关键词： Holocene Ice wedge Stable isotopes Southern permafrost areas Northern Transbaikalia

Circle of life:the common hamster(Cricetus cricetus)adaptations to the urban environment

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Integrative Zoology 2019年第4期14卷 383-395页

作者： Alexey v.SUROv Elena A.ZAYTSEvA Alexandr v.kUPTSOv Elena A.kaTZMAN Pavel L.BOGOMOLOv Alexandra S.SAYAN Ekaterina v.POTASHNIkOvA Nikolay N.TOvPINETZ Ekaterina v.kUZNETSOvA Alexey Y.TSELLARIUS natalia Y.FEOkTISTOvA Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Centre of Hygiene and Epidemiology in Crimea and in the Municipal City Sevastopol SimferopolRussia

Traditionally,urbanization has been seen as a negative phenomenon for ***,changes in the environmental parameters induced by urbanization might be favorable for some *** the past half-century,the common hamster has actively populated cities,establishing populations in some European,Russian and kazakhstan *** on integrative methods,we investigated free-range common hamsters inhabiting Simferopol from 2015 to 2018 to reveal possible adaptations to the urbanized environment across several parameters,including lifespan,hibernation period,reproductive activity and body *** show that in urban areas,the common hamster demonstrates an extremely short hibernation period compared to other localities,possibly due to enhanced food resources from urban forestry(walnuts,locus and hazelnut),allowing the species to start breeding very early(February)and finish as late as *** present the first evidence of polyandry for this species:mating of receptive females with several males and subsequent confirmation of multiple *** high reproductive potential,the lifespan of the common hamster in urban conditions is generally very short(less than 1 year).We speculate that in the process of synurbization,the common hamster’s innate plasticity across many life history traits permits it to successfully colonize throughout a wide range of habitats,with the ability to form novel adaptations to urban environments.

关键词： body mass hibernation lifespan multiple paternity synurbization

Adenosine deaminase isoenzymes estimation - as a diagnostic tool for tuberculous pleural effusions

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Asian Pacific Journal of Tropical Medicine 2009年第5期2卷 61-65页

作者： nalla Nk Prasad CE Gopalakrishniah v Somayajulu vL Lakshmi k Chelluri Gandhi Medical College MusheerabadHyderabad 500020(A.P)India Stem Cell Lab Global HospitalsLakdi-Ka-PoolHyderabad 500004(A.P)India

Objective:To assess the efficacy of ADA isoenzyme estimation over that of total ADA level in pleural fluid and serum as a more efficient diagnostic indicator in tuberculous pleural effusions in high prevalence country like ***:The efficacy was analysed in total thirty four patients of pleural *** ADA was estimated by Guitsi and Galanti Calorimetric method and ADA isoenzymes with and without EHna[Erythro-9-（2- hydroxy-3-nonyl） adenine]a potent ADA1 inhibitor using the same ***:The results demonstrated a statistically significant values of ADA2 in serum（Pvalue for the ratio of pleural fluid ADA2/serum ADA2（P2（Pvity and specificity values of pleural fluid ADA|2 is 81.8%and 91.6%（cut off value 60 IU/L for Tuberculous effusions）,serum ADA2 95.4%and 66%（cut off value 70 IU/L for tuberculous effusions）. ADA2 is an isoenzyme,which is significantly raised in tuberculous pleural effusions both in the serum and pleural ***:Estimation of ADA isoenzymes is redundant as a diagnostic aid over total ADA estimation in view of the limited improvements both in specificity and sensitivity patterns and also in term of cost-benefit ratio.

关键词： Adenosine deaminase Isoenzymes Tuberculous pleural effusions

Isolation and identification of MDR-Mycobacterium tuberculosis and screening of partially characterised antimycobacterial compounds from chosen marine micro algae

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Asian Pacific Journal of Tropical Medicine 2010年第8期3卷 655-661页

作者： Prakash S Sasikala SL Aldous v Huxley J Department of Biotechnology Udaya School of Engineering.K.K.Dist.Tamil Nadu.India Centre for Marine Science and Technology Manonmaniam Sundaranar UniversityRajakkamangalamK.K.Dist.Tamil NaduIndia Department of Zoology Thiru.Vi.Ka.Government Arts CollegeThiruvarur.Tamil NaduIndia

Objective:To isolate the multiple drug resistance(MDR) Mycobacterium tuberculosis(M. tuberculosis) and to screen for the bioactive compounds extracted from marine microalgae. Methods:Sixty seven collected samples that were confirmed by 16S rDna analysis as positive with *** infection were subjected to sensitivity test against commercially used front line and second line drugs by absolute concentration method using LJ *** bacterial isolates numbered I-78,I-101,I-127,I-173,I-202,I-262,I-327 showed resistant for more than 3 drugs were considered as MDR *** the percentage of 10.4 were recorded MDR-TB. Fifteen marine micro algal extracts were screened for antimycobacterial activity and partial characterization of the active principles was ***:The percentage contribution of marine micro algal species on the extraction of antimycobacterials indicated Isochrysis galbana(I. galbana) contain rich bioactive compounds and accounted for 60%inhibition of the total isolates. The percentage contribution of solvents on the extraction of antimicrobials from *** showed that the methanol,chloroform,n-Butanol showed maximum of *** purified eluted compounds(R,0.43) from TLC plate were chromatographed by gas *** eluted sterol compounds showed 13 unsaturated sterols with 3 major ***:The present study indicates the presence of unsaturated fatty acids may have the effect on MDR M. tuberculosis,indicating a potential natural alternative to antibiotics.

关键词： Antimycobacterials Marine micro algae Mycobacterium tuberculosis

Results of the influenza virus surveillance in wild birds in Western part of Mongolia

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Asian Pacific Journal of Tropical Medicine 2010年第2期3卷 90-93页

作者： Marchenko v Yu Alekseev A Yu Tserennorov D Yurlov Ak Susloparov IM Sharshov ka Ilyinykh FA Zolotykh SI Abmed D Otgonbaatar D Shestopalov AM Federal State Research Institution State Research Center of Virology and Biotechnology VectorKoltsovoNovosibirsk RegionRussia national Centre for Diseases with natural Foci UlaanbaatarMongolia Institute of Systematic and Ecology of Animals Siberian BranchRussian Academy of ScienceNovosibirskRussia national Centre for Infectious Diseases UlaanbaatarMongolia

Objective:To present results of virological study of wild birds inhabiting Western Mongolia. Methods:Over a period of 2003-2008,we isolated 13 influenza A viruses:H1N1,H3N6, H13N8 and H4N6 *** did not isolate any H5N1 subtype,that still cause epizooty in wild birds and ***:We revealed taxonomic and ecological heterogeneity of the birds involved in maintenance of circulation of influenza viruses in the given *** viruses were isolated from birds of 6 orders;among them there are species preferring water and semi-aquatic biotopes,one species preferring dry plain region,and also one species which can inhabit both dry and water ***:Representatives of all main orders of Western Mongolia avifauna are involved in support of influenza A virus circulation,highly pathogenic H5N1 influenza viruses were registered in Mongolia thus it’s necessary to continue permanent influenza virus surveillance in wild birds’ populations.

关键词： Influenza A virus Mongolia Wild birds