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Testate amoebae communities from some freshwater and soil habitats in China （Hubei and Shandong Provinces）

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Frontiers of Earth Science 2012年第1期6卷 1-9页

作者： Anatoly BOBROV yuri MAZEI Viktor CHERNYSHOV Yingchun GONG Weisong FENG Department of Soil Geography Moscow State University Moscow 119899 Russia Department of Zoology and Ecology Penza State Pedagogical University Penza 440026 Russia Laboratory of Protozoan Taxonomy and Ecology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

Seventy-eight species and forms of testate amoebae were identified from 29 freshwater and soil habitats in three territories of China （Shandong and Hubei Provinces）. Most abundant species from the genera Plagiopyxis, Centropyxis and Trinema represent the globally-distributed and eurybiont group of testate amoe- bae. The species richness was observed to be the lowest （7-12 species per biotope） in sandy sediments of the Yangtze River, but considerably higher （20-30 taxa） in soil environment. In the range of terrestrial habitats, the most remote communities from Laoshan Mountain in Shandong Province, China manifested the highest difference from others. On the other hand, communities originated in the most distant from industrial center places （Guifeng Mountain in Hubei Province, China） possess the most peculiar species composition including specific Gondwa- nian taxa （e.g. Nebela bigibbosa）. In sum, the results obtained provide the evidence that the community complexity and specificity reduce in the places located within areas that are highly populated and intensively visited by humans.

关键词： testate amoebae soil protists fi'eshwaterprotists China

Local-environment dependence of stacking fault energies in concentrated solid-solution alloys

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npj Computational Materials 2019年第1期5卷 1032-1038页

作者： Shijun Zhao yuri Osetsky G.Malcolm Stocks Yanwen Zhang Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Department of Mechanical Engineering City University of Hong KongHong KongChina Department of Materials Science and Engineering University of TennesseeKnoxvilleTN 37996USA

Concentrated solid-solution alloys(CSAs)based on 3d transition metals have demonstrated extraordinary mechanical properties and radiation resistance associated with their low stacking fault energies(SFEs).Owing to the intrinsic disorder,SFEs in CSAs exhibit distributions depending on local atomic *** this work,the distribution of SFEs in equiatomic CSAs of NiCo,NiFe,and NiCoCr are investigated based on empirical potential and first-principles *** show that the calculated distribution of SFEs in chemically disordered CSAs depends on the stacking fault area using empirical potential *** on electronic structure calculations,we find that local variations of SFEs in CSAs correlate with the charge density redistribution in the stacking fault *** further propose a bond breaking and forming model to understand and predict the SFEs in CSAs based on the local structure *** is shown that the perturbation induced by a stacking fault is localized in the first-nearest planes for NiCo,but extends up to the third nearest planes for NiFe and NiCoCr because of partially filled d electrons in Fe and Cr.

关键词： alloys fault stacking

Atomistic material behavior at extreme pressures

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npj Computational Materials 2016年第1期2卷 93-96页

作者： Laurent Karim Béland yuri N Osetsky Roger E Stoller Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTNUSA

Computer simulations are routinely performed to model the response of materials to extreme environments,such as neutron(or ion)*** latter involves high-energy collisions from which a recoiling atom creates a so-called atomic displacement *** cascades involve coordinated motion of atoms in the form of supersonic *** shockwaves are characterized by local atomic pressures 415 GPa and interatomic distances o2Å.Similar pressures and interatomic distances are observed in other extreme environment,including short-pulse laser ablation,high-impact ballistic collisions and diamond anvil *** cascade simulations using four different force fields,with initial kinetic energies ranging from 1 to 40 keV,show that there is a direct relationship between these high-pressure states and stable defect *** important shortcoming in the modeling of interatomic interactions at these short distances,which in turn determines final defect production,is brought to light.

关键词： extreme defect latter

Gene editing applications to modulate crop flowering time and seed dormancy

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aBIOTECH 2020年第4期1卷 233-245页

作者： Olena Kishchenko Yuzhen Zhou Satyvaldy Jatayev yuri Shavrukov Nikolai Borisjuk Jiangsu Key Laboratory for Eco-Agricultural Biotechnology around Hongze Lake School of Life SciencesHuaiyin Normal UniversityHuai’anChina Jiangsu Collaborative Innovation Centre of Regional Modern Agriculture and Environmental Protection Huaiyin Normal UniversityHuai’anChina Institute of Cell Biology and Genetic Engineering NAS of UkraineKievUkraine Faculty of Agronomy S.Seifullin Kazakh AgroTechnical UniversityNur-SultanKazakhstan College of Science and Engineering Biological SciencesFlinders UniversityAdelaideAustralia

Gene editing technologies such as CRISPR/Cas9 have been used to improve many agricultural traits,from disease resistance to grain ***,emerging research has used CRISPR/Cas9 and other gene editing technologies to target plant reproduction,including major areas such as flowering time and seed *** related to these areas have important implications for agriculture,as manipulation of flowering time has multiple applications,including tailoring crops for regional adaptation and improving ***,understanding seed dormancy will enable approaches to improve germination upon planting and prevent pre-harvest ***,we summarize trends and recent advances in using gene editing to gain a better understanding of plant reproduction and apply the resulting information for crop improvement.

关键词： Genome editing CRISPR/Cas9 Flowering time Florigen Seed dormancy

Oxygen vacancy and Mn2+induced ferromagnetism in Mn-doped ZnO thin films

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Science China(Technological Sciences) 2019年第10期62卷 1755-1759页

作者： GUAN SuJun NASU Naho ZHANG Yu TAMAMOTO yuri YAMANOBE Maria ZHAO XinWei Department of Physics Tokyo University of ScienceTokyo162-8601Japan Department of Robotics The Open University of GuangdongGuangzhou510091China Department of Materials Science and Engineering Xihua UniversityChengdu610039China

With the purpose of investigating the origin of ferromagnetism(FM), Mn-doped Zn O thin films had been fabricated by radio frequency(rf) magnetron sputtering and subsequent anneal process. The characterization of the Mn-doped Zn O thin films was conducted by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), and superconducting quantum interference device(SQUID). With increasing the anneal temperature from 300°C to 700°C for 3 min, the influence on magnetism of the Mndoped ZnO thin films is slight. While extending the anneal time from 3 to 50 min at 300°C, the influence on magnetism is obvious and the Mn-doped ZnO thin films with 30 min clearly demonstrate FM. Compared with the effect of oxygen vacancy and substitutional Mn2+on the ferromagnetic behavior, OVplays the main role in inducing FM of the Mn-doped ZnO thin films with good crystal structure.

关键词： oxygen vacancy Mn2+ ZnO thin films ferromagnetism

Isotopic Composition of Atmospheric Precipitation in the Cis-Ural Region

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Journal of Earth Science 2022年第3期33卷 831-838页

作者： Alena S.Kazantseva Olga I.Kadebskaya yuri V.Dublyansky Mining Institute of the Ural Branch of the Russian Academy of Sciences PermRussia Institute of Geology University of InnsbruckInnsbruckAustria

Using the Global Network of Isotopes in Precipitation(GNIP)method at three stations in the Cis-Ural region(Iskor,Perm,and Kungur),the monitoring results of the isotope composition of atmospheric precipitation conducted in 2016-2019 are *** lines of meteoric waters were obtained for each station and for the Cis-Ural region as a *** latitudinal zoning of changes in isotope parameters from north to south in the Cis-Ural region is noted,which is related to meteorological *** northern regions are characterized by isotopically light values compared to the southern ***,the correlation relationship between the isotopic compositions of atmospheric precipitation and meteorological parameters at each station is *** analysis data show that about 50%-90%of variations in the isotopic composition of precipitation within the annual cycle are determined by the air *** the same time,the amount of precipitation shows a relationship between the average strength and the isotopic composition of precipitation for a series of observations at Kungur Station;for a series of observations at Iskor and Perm stations,there is no *** in the relationship with meteorological data are explained by different sources of moisture introduction to the station and,accordingly,the formation of the isotopic composition of *** flow of moisture is controlled by the transfer of air masses in different directions,the formation of cyclones and ***,for the northern part of the region during the year is characterized by the predominance of cyclones,whereas for the southern-anticyclones.

关键词： precipitation isotopic composition Cis-Ural region correlation relationship Spear-man’s correlation coefficient

Nitrogen and Carbon Isotope Data of Olenekian to Anisian Deposits from Kamenushka/South Primorye, Far-Eastern Russia and Their Palaeoenvironmental Significance

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Journal of Earth Science 2018年第4期29卷 837-853页

作者： yuri D Zakharov Micha Horacek Alexander M Popov Liana G Bondarenko Far Eastern Geological Institute of Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia BLT Wieselburg Research Center HBLFA Francisco-Josephinum Wieselburg 3250 Austria Institute of Lithospheric Research Vienna University Vienna 1090 Austria

The Kamenushka Formation, exposed in the northern part of South Primorye （Kamennshka-1 and Kamenushka-2 sections）, is one of the few localities in the world with richly fossiliferous Lower-Upper Olenekian sedimentary successions. Lower to Middle Triassic ammonoid-, brachiopod- and conodont-bearing silty-clayey deposits of the Kamenushka-1 and Kamenushka-2 sections have been isotope-geochemically investigated in detail. As a result, these sections, together with the previously investigated Abrek Section, exposed in the southern part of South Primorye, provide almost complete ^15Non- and ^13Corg- records for the Lower Triassic of this region. Nine N- isotope intervals and the five negative C-isotope excursions, reflecting, apparently, unstable climatic and hydrological conditions, have been distinguished in the Lower Triassic of South Primorye. On the basis of the new C-isotope data the Mesohedenstroemia bosphorensis Zone （upper part）, Shimanskyites shimanskyi and Neocolumbites insignis zones of South Primorye are correlated now with the Lower Smithian part of the Yinkeng Formation, the Upper Smithian part of the Helongshan Formation and the Middle Spathian part of the Nanlinghu Formation in South China, respectively, as has been observed in the Abrek, Kamenushka-2, West Pingdingshan and Majiashan sections.

关键词： Triassic N- and C-isotopes palaeoclimatology bio- and chemostratigraphy Pri- morye Russia.

Applications of two electric arc plasma torches for the beneficiation of natural quartz

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 267-273页

作者： yuri-Mikhailovich Grishin Long Miao Lev-Alekseevich Borisov Nikolay-Mikhailovich Serykh Alexey-yurievich Kulagin Department of Thermal physics Bauman Moscow State Technical University Federal State Unitary Enterprise Tsentrkvarts

Experimental beneficiation processes of quartz concentrate in arc plasma torches of two different types and electric powers were studied. An emission scanning electron microscope and a universal laser analyzer were used to investigate the structures as well as the size distributions of grains and microparticles. Inductively coupled plasma–mass spectrometry was used to determine the chemical compositions of nonstructural solid-phase mineral impurities in quartz concentrate. Results related to the modified grains' structure and size distribution, the compositions of impurities, and the gas–liquid inclusions in the quartz concentrate were investigated. The total impurities concentrations in the processed grains were found to satisfy the IOTA-STD standard(industry standard for grading high quality fused quartz products). The optimal condition(i.e., the optimal specific plasma enthalpy) for the production of high-purity quartz in arc plasma torches was found to depend on the geological-genetic type and the structural and textural features(i.e., chemical composition and gas–liquid inclusions) of the quartz concentrate.

关键词： low-temperature plasma beneficiation high purity quartz arc plasma torch IOTA-STD standard

Update on the pathological roles of prostaglandin E_(2) in neurodegeneration in amyotrophic lateral sclerosis

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Translational Neurodegeneration 2023年第1期12卷 464-478页

作者： Hiroshi Nango Komugi Tsuruta Hiroko Miyagishi yuri Aono Tadashi Saigusa Yasuhiro Kosuge Laboratory of Pharmacology School of PharmacyNihon University7-7-1 NarashinodaiFunabashi-ShiChiba 274-8555Japan Department of Pharmacology School of Dentistry at MatsudoNihon University2-870-1 SakaechonishiMatsudo-ShiChiba 271-8587Japan

Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative disease characterized by selective degeneration of upper and lower motor *** pathogenesis of ALS remains largely unknown;however,inflammation of the spinal cord is a focus of ALS research and an important pathogenic process in *** E_(2)(PGE_(2))is a major lipid mediator generated by the arachidonic-acid cascade and is abundant at inflammatory ***_(2)levels are increased in the postmortem spinal cords of ALS patients and in ALS model *** therapeutic effects have been obtained in ALS model mice using cyclooxygenase-2 inhibitors to inhibit the biosynthesis of PGE_(2),but the usefulness of this inhibitor has not yet been proven in clinical *** this review,we present current evidence on the involvement of PGE_(2)in the progression of ALS and discuss the potential of microsomal prostaglandin E syn-thase(mPGES)and the prostaglandin receptor E-prostanoid(EP)2 as therapeutic targets for *** pathways involving prostaglandin receptors mediate toxic effects in the central nervous *** some situations,however,the receptors mediate neuroprotective *** recent studies demonstrated that levels of mPGES-1,which catalyzes the final step of PGE_(2)biosynthesis,are increased at the early-symptomatic stage in the spinal cords of transgenic ALS model mice carrying the G93A variant of superoxide *** addition,in an experimental motor-neuron model used in studies of ALS,PGE_(2)induces the production of reactive oxygen species and subsequent caspase-3-de-pendent cytotoxicity through activation of the EP2 ***,this PGE_(2)-induced EP2 up-regulation in motor neurons plays a role in the death of motor neurons in ALS model *** understanding of the pathophysiologi-cal role of PGE_(2)in neurodegeneration may provide new insights to guide the development of novel therapies for ALS.

关键词： Prostaglandin E_(2) Amyotrophic lateral sclerosis Motor neuron death E-prostanoid receptor Microsomal prostaglandin E synthetase-1