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Maintenance of Species Differences in Closely Related Tetraploid Parasitic Euphrasia (Orobanchaceae) on an Isolated Island

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Plant Communications 2020年第6期1卷 85-99页

作者： Hannes Becher Max R.Brown Gavin Powell Chris Metherell Nick J.Riddifordand Alex D.Twyford University of Edinburgh School of Biological SciencesInstitute of Evolutionary BiologyCharlotte Auerbach RoadEdinburgh EH93FLUK Royal Botanic Garden Edinburgh 20A Inverleith RowEdinburgh EH35LRUK botanical society of britain and ireland 4 High Firs CrescentHarpendenHertfordshire AL51NAUK Schoolton Fair IsleShetland ZE29JUUK

Polyploidy is pervasive in angiosperm evolution and plays important roles in adaptation and ***,polyploid groups are understudied due to complex sequence homology,challenging genome assembly,and taxonomic ***,we study adaptive divergence in taxonomically complex eyebrights(Euphrasia),where recent divergence,phenotypic plasticity,and hybridization blur species *** focus on three closely related tetraploid species with contrasting ecological preferences that are sympatric on Fair Isle,a small isolated island in the British *** a common garden experiment,we show a genetic component to the morphological differences present between these *** wholegenome sequencing and a novel k-mer approach we call“Tetmer”,we demonstrate that the species are of allopolyploid origin,with a sub-genome divergence of approximately 5%.Using2 million SNPs,we show sub-genome homology across species,with a very low sequence divergence characteristic of recent *** genetic variation is broadly structured by species,with clear divergence of Fair Isle heathland Euphrasia micrantha,while grassland Euphrasia arctica and coastal Euphrasia foulaensis are more closely ***,we show that tetraploid Euphrasia is a system of allopolyploids of postglacial species divergence,where adaptation to novel environments may be conferred by old variants rearranged into new genetic lineages.

关键词： incipient speciation k-mer spectrum allopolyploidy tetraploid divergence with gene flow taxonomic complexity

医生在每周48小时工作时间内能得到培训吗?

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中国医院院长 2015年第4期11卷 34-36页

作者： Andrew Hartle Sarah Gibb 梁立智 Association of Anaesthetists of Great britain and ireland London W1B 1PY

能——Andrew Hartle和Sarah Gibb自2009年8月起,英国所有受训医生每周工作时间被限制到4 8小时（平均工作26周）。欧盟工作时间指令（European Working Time Directive）作为对工作时间的规定被写进英国法规,其目的是通过强制规定休息... 详细信息

能——Andrew Hartle和Sarah Gibb自2009年8月起,英国所有受训医生每周工作时间被限制到4 8小时（平均工作26周）。欧盟工作时间指令（European Working Time Directive）作为对工作时间的规定被写进英国法规,其目的是通过强制规定休息时间、年假时间和最多工作周数,提醒人们重视员工的安全和健康。

关键词：工作时间培训质量工作周 Sarah 强制规定临床服务医师培训 Temple 专科培训休息时间

Multi-UAV Trajectory Design and Power Control Based on Deep Reinforcement Learning

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Journal of Communications and Information Networks 2022年第2期7卷 192-201页

作者： Chiya Zhang Shiyuan Liang Chunlong He Kezhi Wang School of Electronic and Information Engineering Harbin Institute of TechnologyShenzhen 518055China National Mobile Communications Research Laboratory Southeast UniversityNanjing 211189.China School of Computer Sciences and Electrical Engineering.Northumbria University 5995 Newcastle upon TyneNewcastleUnited Kingdom of Great Britain and Northern IrelandUK NE18STUK

In this paper,multi-unmanned aerial vehicle(multi-UAV)and multi-user system are studied,where UAVs are served as aerial base stations(BS)for ground users in the same frequency band without knowing the locations and channel parameters for the *** aim to maximize the total throughput for all the users and meet the fairness requirement by optimizing the UAVs’trajectories and transmission power in a centralized *** problem is non-convex and very difficult to solve,as the locations of the user are unknown to the *** propose a deep reinforcement learning(DRL)-based solution,i.e.,soft actor-critic(SAC)to address it via modeling the problem as a Markov decision process(MDP).We carefully design the reward function that combines sparse with non-sparse reward to achieve the balance between exploitation and *** simulation results show that the proposed SAC has a very good performance in terms of both training and testing.

关键词： multi-UAV and multi-user wireless system UAV powercontrol trajectorydesign throughputmaxi-mization SAC

Bi nanoparticles encapsulated in nitrogen-doped carbon as a long-life anode material for magnesium batteries

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Journal of Magnesium and Alloys 2023年第11期11卷 4181-4188页

作者： Junjun Wang Ruohan Yu Jianxiang Wang Juncai Long Fan Qiao Lei Zhang Guanjie He Qinyou An Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Christopher Ingold Laboratory Department of ChemistryUniversity College London20 Gordon StreetLondon WC1H 0AJUnited Kingdom of Great Britain and Northern IrelandUnited Kingdom Hubei Longzhong Laboratory Wuhan University of Technology(Xiangyang Demonstration Zone)Xiangyang 441000China

Bismuth has garnered significant interest as an anode material for magnesium batteries(MBs) because of its high volumetric specific capacity and low working potential. Nonetheless, the limited cycling performance(≤100 cycles) limits the practical application of Bi as anode for MBs. Therefore, the improvement of Bi cycling performance is of great significance to the development of MBs and is also full of challenges. Here, Bi nanoparticles encapsulated in nitrogen-doped carbon with single-atom Bi embedded(Bi@NC) are prepared and reported as an anode material for MBs. Bi@NC demonstrates impressive performance, with a high discharge capacity of 347.5 mAh g^(-1) and good rate capability(206.4 mAh g^(-1)@500 mA g^(-1)) in a fluoride alkyl magnesium salt electrolyte. In addition, Bi@NC exhibits exceptional long-term stability, enduring 400 cycles at 500 mA g^(-1). To the best of our knowledge, among reported Bi and Bi-based compounds for MBs, Bi@NC exhibits the longest cycle life in this work. The magnesium storage mechanism of Bi@NC is deeply studied through X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. This work provides some guidance for further improving the cycling performance of other alloy anodes in MBs.

关键词： Magnesium batteries Bismuth 3D tomography reconstruction Magnesium alloy Single-atom

Psychological Problems after Stroke and Their Management: State of Knowledge

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Neuroscience & Medicine 2012年第1期3卷 83-89页

作者： Ian I. Kneebone Nadina B. Lincoln Institute of Work Health and Organisations University of Nottingham UK. National Health Service of Great britain and Northern ireland (NHS) Improvement-Stroke Team London UK

Background: Stroke has the greatest disabling impact of any chronic disease. Psychological changes including emotional, behavioural and cognitive changes can be common after stroke. Recently more attention has been given to these concerns. Content: This paper considers the nature of these problems, how they can be identified and the evidence for effective interventions. Conclusions: Research is needed into instruments to better identify anxiety after stroke and into treatments for emotional and behavioural changes. Further work is also needed to establish the best means for identifying cognitive deficits after stroke, particularly executive and memory problems, and into the optimal means of ameliorating these deficits.

关键词： Stroke Emotional Disturbances Cognition Disorders Therapy

Effect of grassland management on the occurrence of the poisonous species Senecio jacobaea

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Effect of grassland management on the occurrence of the pois...

Origin and evolution of the genera Lonsdaleia and Actinocyathus:Insights for the Mississippian palaeogeography from the western Palaeotethys

ⅩⅪ International Grassland Congress and the Ⅷ International Rangeland Congress

作者： M.Suter J.Connolly A.Lüscher Swiss Grassland society Reckenholzstrasse 1918046 ZurichSwitzerland UCD School of Mathematical Sciences University College DublinDublin 4Ireland Agroscope Reckenholz-Tanikon Research Station ART Reckenholzstrasse 1918046 ZurichSwitzerland

＜正＞Introduction Senecio jacobaea L.（tansy ragwort） is a poisonous weed in grasslands of various coritinents（*** States, Great britain,Central Europe,New Zealand）.In Central Europe,the species seems to have increased its dispersion in the last *** further spread of the species into farmland must be prevented because *** contains pyrrolizidine-alkaloids

关键词： weed control nitrogen applied continuous grazing openness of sward case-control study

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Journal of Palaeogeography 2023年第2期12卷 296-310页

作者： Isabel Rodríguez-Castro Ian D.Somerville Sergio Rodríguez Departamento de Geodinamica Estratigrafía y PaleontologíaUniversidad Complutense de Madrid28040MadridSpain UCD School of Earth Sciences University College DublinBelfieldDublin 4Ireland Instituto de Geociencias(CSIC UCM)Ciudad Universitaria28040MadridSpain

Representatives of the subfamily Lonsdaleiinae Chapman,1893 are common in the Mississippian of the western Palaeotethys.A general analysis of the origin,distribution and evolution of that subfamily has been *** most probable hypothesis for the origin of the genus Lonsdaleia McCoy,1849 is to acquire colonialism via the genus Axophyllum Milne Edwards and Haime,*** d'Orbigny,1849 would be a descendant of Lonsdaleia by increasing integration in the *** first occurrences of Lonsdaleia have been recorded in the lower Visean from northern britain and northern Tianshan Mountains of northwestern China,but the diversification and migration to the whole Palaeotethys only happened in the late *** hypotheses are proposed on that *** Serpukhovian was also a period of migrations and diversification for these *** Lonsdaleia and Actinocyathus have been recorded in Bashkirian refuges,the Sverdrup Basin in northern Laurasia and the Tindouf Basin in northern Africa,*** division of the western Palaeotethys into six subprovinces based on the distribution of corals is proposed.

关键词： Carboniferous Palaeotethys Biogeography Evolution Rugosa

Climate change and contrasting plasticity in timing of a two-step migration episode of an Arctic-nesting avian herbivore

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Current Zoology 2014年第2期60卷 233-242页

作者： Anthony David FOX Mitch D.WEEGMAN Stuart BEARHOP GeoffM.HILTON Larry GRIFFIN David A.STROUD Alyn WALSH Department of Bioscience Aarhus University Kalo Grenavej 14 DK-8410 Ronde Denmark Centre for Ecology and Conservation College of Life and Environmental Sciences University of Exeter Cornwall CampusTR10 9EZ UK Wildfowl and Wetlands Trust Slimbridge Gloucester GL2 7BT UK Wildfowl and Wetlands Trust Eastpark Farm Caerlaverock Dumfriesshire DGI 4RS UK Greenland White-fronted Goose Study c/o Spring Meadows Taylors Green Warmington Peterborough PE8 6TG UK National Parks and Wildlife Service Wexford Wildfowl Reserve North Slob Wexford Ireland

Greenland white-fronted geese Anser albifrons flavirostris wintering in britain and ireland migrate over the sea for 700-1200 km to stage 3-5 weeks in Iceland in spring, continuing a similar distance over the sea and Greenland Ice Cap to West Greenland breeding grounds. During 1969 to 2012, the geese advanced the mean departure date from ireland by 15 days, during which time also they attained threshold fat stores earlier as well as departing in fatter condition. Over that period, Iceland spring-staging geese shifted from consuming underground plant storage organs to grazing managed hayfields, which provide fresh grass growth despite sub-zero temperatures, when traditional natural foods are inaccessible in frozen substrates. In 2012 and 2013, geese arrived three weeks earlier to Iceland, in fatter condition and accumulated fat significantly slower than in 1997-1999 and 2007. Although geese accumulated sufficient fat stores earlier in Iceland in 2007, 2012 and 2013, they departed around the same date as in 1997-1999, prolonging spring staging by three weeks. Plasticity in winter departure dates is likely due to improved winter feeding conditions （enabling earlier departure in better condition） and a novel predictable food resource in Iceland. Greenland white-fronted geese attained threshold fat stores in Iceland earlier, but remained rather than departing earlier to Greenland. Despite arriving earlier in Iceland, arrival dates on the breeding areas have not changed since the 1880s, presumably because of relatively constant cool springs and heavy snowfall in West Greenland during recent years [Current Zoology 60 （2）： 233-242, 2014].

关键词： Anser albifronsflavirostris Climate mismatch Greenland white-fronted geese Migration phenology Vernalmigration