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w.ld grapevine(Vitis vinifera ***)in the Hyrcanian relict forests of northern Iran:an overview.of current taxonomy,ecology and palaeorecords

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Journal of Forestry Research 2018年第6期29卷 1757-1768页

作者： Alireza Naqinezhad Elias Ramezani Morteza Djamali Annik Schnitzler Claire arnold Department of Biology Faculty of Basic SciencesUniversity of MazandaranBabolsarMazandaranIran Department of Forestry Faculty of Natural ResourcesUrmia UniversityUrmiaIran Institut Mediterraneen de Biodiversite et d’Ecologie(IMBE UMR 7263CNRS-Aix Marseille Universite-IRD-Universite d’Avignon)Europole mediterraneen de l'Arboisbatiment VilleminBP8013545 Aix-En-Provence Cedex 04France Laboratoire Interdisciplinaire des Environnements Continentaux LIEC-UMR 7360 CNRSUniversity of LorraineMetzFrance University of Lausanne Unicentre1015 LausanneSwitzerland

Due to severe anthropogenic impacts on low.and and submontane zones of the Hyrcanian forests of northern Iran, w.ld grapevine(Vitis vinifera subsp. sylvestris), a sporadically distributed w.ody liana, is currently considered an endangered species. Using data from the literature and 34 studied populations, herbarium assessments and nine palynological sites, w. provide an overview.of its taxonomy,distribution and ecology in the first part of the *** separation of the tw. subspecies, namely V. sylvestris subsp. anebophylla and V. sylvestris subsp. trichophylla(sensu Flora Iranica), based on their leaf indumentums, could not be confirmed by our examination of herbarium materials and field observations. Indumentum of the leaves is a result of leaf polymorphism in different Vitis specimens and can be strongly influenced by environmental conditions. Vitis vinifera subsp. sylvestris grow. in a w.de range of habitats including w.tlands, seasonal stream sides in closed forests,alluvial beds of large rivers, sand dune shrublands and forested w.tlands(alder forests). Parrotia persica and Carpinus betulus w.re the most frequent host species in the studied populations. In the Hyrcanian region, no pollen record of Vitis older than the Mid-or Late-Holocene has yet been established. Despite the intrinsic problem in pollen identification by normal(i.e., light) microscopy of w.ld from cultivated grapevines, the significant values and persistent occurrence of Vitis pollen since the Mid-Holocene(before the Bronze Age) in the Hyrcanian pollen records may imply the onset of viticulture in low.to mid-elevation sites in the region. This represents an argument to consider the Hyrcanian region as a possible domestication center for V. ***, the question of w.ld versus cultivated origin of grapevines in the Hyrcanian pollen records and the possible date of its domestication and/or cultivation w.ll remain open until further palynological studies are undertaken.

关键词： Domestication Grapevine Hyrcanian forests Pollen Vitis

Mesenchymal stem cells and COVID-19:the process of discovery and of translation

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Biomaterials Translational 2021年第4期2卷 307-311页

作者： arnold I.Caplan Skeletal Research Center Department of BiologyCase Western Reserve UniversityClevelandOHUSA

Mesenchymal stem cells w.re developed as a cell-based therapeutic in the 1990’*** translation of culture expanded mesenchymal stem cells from a basic science focus into a modern therapeutic has taken 30 *** current state of the basic science information argues that mesenchymal stem cells may be curative for coronavirus disease 2019(COVID-19).Indeed,early small-scale clinical trials have show. positive *** issue raised is how.to assemble the resources to get this cell-based therapy approved for clinical *** technology is complex,the COVID-19 viral infections are life threatening,the cost is high,but human life is *** w.ll it take to perfect this potentially curative technology?

关键词： COVID-19 discovery research mesenchymal stem cell translation

Governance interactions of spatial data infrastructures: an agent-based modelling approach

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作者： (美)arnold

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International Journal of Digital Earth 2021年第6期14卷 696-713页

作者： Jaap-w.llem Sjoukema Jalal Samia arnold K.Bregt Joep Crompvoets Laboratory of Geo-Information Science and Remote Sensing Wageningen University&ResearchWageningenThe Netherlands KU Leuven Public Governance Institute LeuvenBelgium Department of Geography and Urban Planning University of MazandaranBabolsarIran

In order to facilitate and coordinate spatial data sharing and exchange,many organisations have developed spatial data infrastructures(SDIs).SDI governance plays a pivotal role in the development and evolution of an SDI,but as SDIs are complex adaptive systems,governing is a *** research therefore proposes a complexity perspective to SDI governance by exploring the use of agent-based modelling to simulate and examine SDI governance *** this agent-based simulation,w. examine interactions betw.en SDI stakeholders,data availability and the effects of different governance styles(hierarchical,netw.rk and laissez-faire governance)and budget *** simulation show. that it is possible to mimic SDI governance dynamics through agent-based *** running different scenarios,it appears that a netw.rk approach is more successful compared to a hierarchical or laissez-faire *** validation show. that overall the results of the simulation are credible and insightful,although improvements can be made to make the model more *** agent-based modelling,SDI governance becomes more tangible and visible,w.ich facilitates discussion and ***-based modelling therefore appears to be a helpful new.approach in a better understanding of the complexities and dynamics of SDI governance.

关键词： Governance spatial data infrastructure(SDI) agentbased modelling funding models complex adaptive systems

Variation in mantle lithology and composition beneath the Ngao Bilta volcano,Adamaw. Massif,Cameroon volcanic line,w.st-central Africa

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Geoscience Frontiers 2020年第2期11卷 665-677页

作者： Robert Temdjim Merlin Patrick Njombie w.gsong arnold Julien Nzakou Tsepeng Stephen Foley Department of Earth Sciences Faculty of SciencesUniversity of Yaounde IP.O.Box.812 YaoundeCameroon Department of Earth and Planetary Sciences and ARC Centre of Excellence for Core to Crust Fluid Systems Macquarie UniversityNorth RydeNSW2109Australia

Mantle peridotites entrained as xenoliths in the lavas of Ngao Bilta in the eastern branch of the continental Cameroon Line w.re examined to constrain mantle processes and the origin and nature of melts that have modified the upper mantle beneath the Cameroon *** xenoliths consist mainly of lherzolite w.th subordinate harzburgite and *** commonly contain olivine,orthopyroxene,clinopyroxene and spinel although the dunite is *** is an essential constituent in the *** chemistry differs betw.en the three types of peridotite:olivines have usual mantle-like Mg#of around 90 in lherzolites,but follow.a trend of decreasing Mg#(to 82)and NiO(to 0.06 w..%)that is continuous in the *** also contain orthopyroxenes and/or clinopyroxenes w.th low.Mg#,indicating a reaction that removes Opx and introduces Cpx,olivine,amphibole and *** is attributed to reaction w.th a silica-undersaturated silicate melt such as nephelinite or basanite,w.ich originated as a low.degree melt from a depleted source as indicated by low.Al2O3 and Na2O in Cpx and high Na2O/K2O in *** estimates place the xenoliths at pressures of 11–15 kbar(35–50 km)and temperatures of 863–957C,along a dynamic rift geotherm and shallow.r than the region w.ere carbonate melts may *** melt/rock reactions exhibited by the Ngao Bilta xenoliths are consistent w.th their peripheral position in the eastern branch of the Cameroon Volcanic Line in an area of thinned crust and lithosphere beneath the Adamaw. Uplift.

关键词： Cameroon volcanic line Adamaw. volcanic massif Peridotite xenoliths Partial melting Melt-rock reactions

Performance of Senior Secondary School Students in Mathematics in the Bolgatanga Municipality of the Republic of Ghana

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Performance of Senior Secondary School Students in Mathemati...

作者： arnold Amasiya Asanga 浙江师范大学

学位级别：硕士

Debilitating standards and records of w.rrying grades attained by some secondary school candidates,for instance,indicate that most students underperform in the subject area of mathematics,a challenge mainly caused by lack of basic concepts clearly explained for students to *** study w.s conducted to explore the performance of senior secondary school students in mathematics in the Bolgatanga Municipality of the Republic of *** study adopted a qualitative exploratory descriptive research *** research population included teachers,students and educational *** sampling technique w.s used to sample participants in the study *** on the findings,it w.s found that,w.ak beginning of students w.s a cause of poor performance in *** findings also show.d that,low.interests of students in learning mathematics w.re identified as a cause of poor performance of students in *** results also show.d that,few.students had positive attitude tow.rds the study of *** results further show.d that,respondents cited encouragement from teachers,aw.kening students interested and improving know.edge of students on mathematics as w.ys to improve students’ performance in *** on the findings,the researcher concluded that,students’ performance in mathematics w.s not encouraging at the Bolgatanga Municipality in the Republic of *** researcher recommended that more counseling should be provided to secondary school students in the study setting to encourage them to improve their know.edge of mathematics by teachers and educational administrators.

关键词： Performance of Mathematics Senior High Schools Attitudes tow.rds Mathematics Teaching methods

Effect of Planting Density, Irrigation Regimes, and Maize Hybrids w.th Varying Ear Size on Yield, and Aflatoxin and Fumonisin Contamination Levels

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American Journal of Plant Sciences 2012年第10期3卷 1341-1354页

作者： Hamed K. Abbas Henry J. Mascagni Jr. H. arnold Bruns w. Thomas Shier Department of Medicinal Chemistry College of Pharmacy University of Minnesota Minneapolis USA 5Department of Plant Pathology & Crop Physiology Louisiana State University AgCenter Baton Rouge USA. United States Department of Agriculture-Agricultural Research Service Biological Control of Pests Research Unit Stoneville USA United States Department of Agriculture-Agricultural Research Service Crop Production Systems Research Unit Stoneville USA Northeast Research Center Louisiana State University AgCenter St. Joseph USA

Corn (maize, Zea mays L.) hybrids expressing the flexibility trait in ear size (number of kernels per ear) are marketed for ability to give higher yields under adverse conditions. Altered kernel number is associated w.th altered number of silk, a major route for infection of kernels by aflatoxin-producing fungi such as Aspergillus flavus. The effect of plant density and irrigation level on yield and accumulation of aflatoxins and fumonisins in harvested grain w.s compared in a fixed-ear hybrid (Pioneer 33K81), a semi-flexible ear hybrid (Pioneer 3223) and a flexible ear hybrid (Golden Acres 8460) over a range of seeding densities (49,400, 61,750, 74,700, 86,450, and 98,800 seeds·ha–1) in non-irrigated, moderately-irrigated (6.4 cm soil w.ter deficit) and w.ll-irrigated plots (3.8 cm soil w.ter deficit), during three years w.th variable rainfall. Irrigation increased yields in all hybrids, but in the absence of irrigation, yields w.re highest w.th the semi-flexible ear trait hybrid. In general, the hybrid w.th the flexible ear trait had low.r optimal seeding densities than the other hybrids for each soil w.ter regime. In general, kernel number w.s least affected by seeding density in the hybrid w.th fixed-ear trait compared to the semi- and flexible ear hybrids. The low.st levels of aflatoxin and of fumonisin contamination in harvested grain w.re associated w.th the flexible ear trait at all rainfall and irrigation levels, but there w.s no evidence that reducing stress by low.ring seeding density reduced mycotoxin contamination. Inoculation w.th A. flavus resulted in much higher levels of aflatoxin and significantly higher levels of fumonisin contamination in grain of all hybrids under most conditions of rainfall and irrigation, suggesting that factors that promote A. flavus infection can affect production of both mycotoxins.

关键词： Aflatoxin Fumonisin Mycotoxin Corn Maize Environmental Manipulation Irrigation Flexible Kernel Number Trait

The Soft X-ray Imager(SXI)on the SMILE Mission

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Earth and Planetary Physics 2024年第1期8卷 5-14页

作者： S.Sembay A.L.Alme D.Agnolon T.arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin G.Branduardi-Raymont T.Craw.ord J.P.Breuer T.Buggey G.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Craw.ord N.Eaton C.Feldman C.Forsyth T.Frantzen G.Galgóczi J.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer M.Guedel Y.Guo M.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland S-Y.Hsieh M.w.J.Hubbard H.Jeszenszky M.Jones T.Kennedy K.Koch-Mehrin S.Kögl S.Krucker K.D.Kuntz C.Lakin G.Laky O.Lylund A.Martindale J.Miguel Mas Hesse R.Nakamura K.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel J.Pearson G.Peikert F.S.Porter T.Pouliantis B.H.Qureshi w.Raab G.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman S.Sachdev A.Samsonov M.Soman D.Sibeck S.Smit J.Søndergaard R.Speight S.Stavland M.Steller TianRan Sun J.Thornhill w.Thomas K.Ullaland B.w.lsh D.w.lton C.w.ng S.Yang School of Physics and Astronomy University of LeicesterLeicesterLE17RHUK Space Park Leicester University of LeicesterLeicesterLE17RHUK Mullard Space Science Laboratory University College LondonDorkingRH56NTUK Centre for Electronic Imaging Open UniversityMilton KeynesMK76 AAUK Birkeland Centre for Space Science Department of Physics and TechnologyUniv.of BergenN-5007 BergenNorway University of Vienna A-1010 ViennaAustria Space Research Institute Austrian Academy of SciencesA-8042 GrazAustria National Institute of Aerospace Technology MadridSpain ESTEC European Space Agency2201 AZ NoordwijkNetherlands State Key Laboratory of Space w.ather National Space Science CentreBeijing 100190China University of Applied Sciences and Arts Northw.stern Sw.tzerland CH-5210 WindischSwitzerland Koegl Space GmbH CH-8157 DielsdorfSwitzerland Space Acoustics GmbH CH-8157 DielsdorfSwitzerland Zurich University of Applied Sciences 8400 WinterhurSwitzerland Genov Solutions N-5172 LoddefjordNorway STM Engineering N-5165 LaksevagNorway John Hopkins University Applied Physics Laboratory MD 20723USA NASA/Goddard Space Flight Centre MD 20771USA Center for Space Physics Boston UniversityBostonMA 02215USA Department of Theoretical Physics and Astrophysics Masaryk University60177 BrnoCzech Republic Institute of Physics E¨otvo¨s Lor´and University1053 BudapestHungary Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100045China Centro de Astrobiologia(CAB) CSIC-INTAMadridSpain

The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar w.nd Magnetosphere Ionosphere Link Explorer(SMILE)*** is a joint science mission betw.en the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in *** is a compact X-ray telescope w.th a w.de field-of-view.FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE *** is sensitive to the soft X-rays produced by the Solar w.nd Charge eXchange(Sw.X)process produced w.en heavy ions of solar w.nd origin interact w.th neutral particles in Earth’s *** provides a mechanism for boundary detection w.thin the magnetosphere,such as the position of Earth’s magnetopause,because the solar w.nd heavy ions have a very low.density in regions of closed magnetic field *** sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few.minutes and the orbit of SMILE w.ll enable such movements to be tracked for segments lasting many *** is led by the University of Leicester in the United Kingdom(UK)w.th collaborating organisations on hardw.re,softw.re and science support w.thin the UK,Europe,China and the United States.

关键词： Soft X-ray Imaging micropore optics large area CCD

Opening the black box of donor influence on Digital Earth in Africa

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International Journal of Digital Earth 2013年第S2期6卷 1-21页

作者： Kate T.Lance Yola P.Georgiadou arnold K.Bregt Faculty of Geo-Information Science and Earth Observation University of TwentePO Box 2177500 AEEnschedeThe Netherlands Centre for Geo-Information Wageningen University and Research CentrePO Box 476700 AAWageningenThe Netherlands

Africa’s participation in Digital Earth is *** is a tendency to ascribe this state to prevailing governance and cultural challenges in ***,foreign actors such as donors have an apparent role in shaping geospatial policies and *** far,the complex linkages betw.en external aid and improved social and environmental monitoring and decision-making have been handled as a kind of‘black box’.To better understand the situation,w. open the box and focus on the interaction betw.en donors and *** use a heuristic from political science,as w.ll as empirical evidence,to describe the policyinfluencing tools that donors employ based on four basic resources donors possess:organization,authority,treasure,and *** show.an evolution of tool usage as donors shift from‘old aid’to‘new.aid’*** new.tools include:technical assistance for geospatial curriculum development,inscription of standards and data access requirements in contracts and grants,cross-agency project design,best-practice analysis,portfolio management,and the use of language to promote participation and *** these tools reflect donor intent to partner in the realization of Digital Earth,the tools stem from a persisting asymmetric pow.r dynamic betw.en donors and policy-makers.

关键词： foreign aid donors policy outcomes tools geospatial technologies