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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

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Influence of social upbringing on the activity pattern of captive lion Panthera leo cubs:Benefits of behavior enrichment

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Current Zoology 2010年第4期56卷 389-394页

作者： Sibonokuhle NCUBE hilton Garikai Taambuka NDAGURWA African Lion and Environmental Research Trust (ALERT) Department of Forest Resources and Wildlife Management Faculty of Applied Sciences National University of Science and Technology

The influence of social upbringing on the activity pattern of lion Panthera leo cubs was investigated at three sites. In this study, stimulus objects such as sticks, grass, fresh dung （elephant Loxondota africana, zebra Equus quagga, impala Aepyceros melampus, duiker Sylvicapra grimmia, kudu Tragelaphus strepsiceros, giraffe Giraffa camelopardalis and wildebeest Connochaetes taurinus） and cardboard boxes, were utilized in an enrichment program aimed at encouraging active behaviors of captive lion cubs at Antelope Park and Masuwe. Lion cubs at Chipangali were not behaviorally enriched. Activity patterns were recorded for 10 days at each site. We recorded moving, resting, playing, grooming, visual exploration and display of hunting instincts. We found that behavioral enrichment enhanced the active behaviors of captive lion cubs. Orphan-raised cubs spent more time moving, playing and displaying hunting instincts than mother-raised cubs, but the time spent grooming was similar across areas and suggests that grooming is not influenced by enrichment. Mother-raised cubs spent more time engaged in visual exploration than orphan-raised cubs and this could be a behavior acquired from mothers or a result of confidence to explore because of their presence. Activity patterns were different among time treatments across our three study sites. Based on these findings, we suggest that lion cubs raised in captivity could benefit from behavioral enrichment to encourage active behaviors essential for eventual reintroduction into the wild

关键词： Activity pattern Panthera leo Lion cub Behavioral enrichment Orphan raised Mother raised

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The Potential of High Power Lasers for Tube Cutting and Concrete Scabbling in Nuclear Decommissioning

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稀有金属材料与工程 2011年第S4期40卷 252-256页

作者： Paul hilton Ali Khan TWI Ltd.Granta Park Cambridge CB21 6ALUK

Contaminated concrete and metal pipework presents a major nuclear decommissioning challenge in terms of the total volumes of material to be treated,the radiation levels present and the number of facilities *** recently,industrial lasers have often been seen as too unreliable for use in nuclear decommissioning environments and hence their usage has been *** advent of solid state 'fibre' lasers has,however,provided a robust and reliable industrial tool,capable of performing not only concrete scabbling but other laser based decommissioning processes,such as *** concrete scabbling has been demonstrated in the laboratory,to date,no representative scale demonstration has been provided which would give industry confidence in the *** paper will describe the development of a laser scabbling process head,equipped with an integrated debris collection device and adaptive control system for automatic maintenance of the attitude and stand off distance of the head from the concrete *** results of using optical fibre delivered laser power to remove the surface of a range of representative and large scale concrete samples will be *** 5kW of laser power,removal rates up to 7000 cc of concrete per hour have been recorded at a removal depth of the order *** paper will also report on the results of using the same laser source,for single-sided cutting of various 304L stainless steel tubes,of diameter up to 170mm and wall thickness up to *** results show that with the right optical configuration,it is entirely possible to laser cut tubes from one side,at extremely long and safe standoff distances,if the main objective is simply to sever the tube.

关键词： lasers concrete scabbling tube cutting.

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An efficient framework for ensemble of natural disaster simulations as a service

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Geoscience Frontiers 2020年第5期11卷 1859-1873页

作者： Ujjwal KC Saurabh Garg James hilton Discipline of ICT University of TasmaniaHobartAustralia Data61 CSIROMelbourneAustralia

Calculations of risk from natural disasters may require ensembles of hundreds of thousands of simulations to accurately quantify the complex relationships between the outcome of a disaster and its contributing *** large ensembles cannot typically be run on a single computer due to the limited computational resources *** Computing offers an attractive alternative,with an almost unlimited capacity for computation,storage,and network ***,there are no clear mechanisms that define how to implement these complex natural disaster ensembles on the Cloud with minimal time and *** such,this paper proposes a system framework with two phases of cost optimization to run the ensembles as a service over *** cost is minimized through efficient distribution of the simulations among the cost-efficient instances and intelligent choice of the instances based on pricing *** validate the proposed framework using real Cloud environment with real wildfire ensemble scenarios under different user *** experimental results give an edge to the proposed system over the bag-of-task type execution on the Clouds with less cost and better flexibility.

关键词： Wildfire prediction Ensemble simulation Cloud computing Natural disaster models

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On the Extended Genus

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Acta Mathematica Sinica,English Series 1988年第4期4卷 372-382页

作者： Peter hilton Department of Mathematical Sciences SUNY Binghamton NY

Ⅰ. Introduction For finitely generated nilpotent groups G, we describe the genus of G as the set of isomorphismclasses of finitely generated nilpotent groups H such that the Iocalizations of G and H are isomorphicat ... 详细信息

关键词： On the Extended Genus

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Low Power Laser Surfi-Sculpt

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稀有金属材料与工程 2011年第S4期40卷 147-150页

作者： J.E.Blackburn P.A.hilton Laser and Sheet Processes Group TWI LtdCambridgeCB21 6ALUnited Kingdom

The functional properties of materials can be enhanced using surface features,for instance;to improve the thermal properties of heat *** development of the laser Surfi-Sculpt process over the past decade has resulted in a technology capable of producing a wide variety of features in metallic ***,the potential for producing similar features in polymeric and ceramic substrates also *** the potential for utilizing high power focused laser beams to produce surface features using this process has been *** paper details the results of recent trials performed with a 200 Yb-fibre laser and a galvanometer driven beam scanner for producing surface features using the Surfi-Sculpt process.A compact,cheap,easily robotically automated,laser Surfi-Sculpt machine,being able to operate at atmospheric pressure may have potential in a range of industry sectors.

关键词： laser surfacing Yb-fibre surfi-sculpt

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Adaptively Controlled Hybrid Welding Using a High Brightness Laser

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稀有金属材料与工程 2011年第S4期40卷 1-5页

作者： C.M.Allen P.A.hilton TWI Ltd Granta ParkGreat AbingtonCambridgeCB21 6ALUnited Kingdom

Hybrid laser-MAG welding with real-time adaptive control has been *** welding conditions have been developed to produce ISO 13919-1 class B (stringent) quality butt welds between 8mm thickness steel plates,using a 5kW *** Yb fibre laser combined with conventional arc welding equipment.A laser vision seam tracking system has enabled a 7-axis robot,manipulating the hybrid welding head,to track butt joints in real time during *** laser vision system has also provided information on the variations in joint fit-up,in particular the width of any gaps,or height of any mismatches *** information has then been used to automatically adjust the robot position or speed,or arc welding parameters,depending on the fit-up *** this way,the tolerance of the hybrid process has been augmented,producing stringent quality welds over a wider range of joint fit-up cases than when using fixed conditions alone.

关键词： hybrid welding steel adaptive control fit-up tolerance

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On Groups of Pseudo-integers

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Acta Mathematica Sinica,English Series 1988年第2期4卷 189-192页

作者： Peter hilton Department of Mathematical Sciences State University of New York

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Endemic fossil seed plants from China and a reassessment of coniferophyte phylogeny

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Progress in Natural Science:Materials International 1999年第10期9卷 48-55页

作者： Jason hilton,王士俊,陈之端,田宝霖 Department of Palaeobotany Institute of Botany Chinese Academy of Sciences Beijing 100093 China Department of Palaeobotany Institute of Botany Chinese Academy of Sciences Beijing 100093 China Laboratory of Systematics and Evolution Institute of Botany Chinese Academy of Sciences Beijing 100093 China China University of Mining and Technology ( Beijing) Beijing 100083 China

Recent palaeobotanical studies have provided new and important evidence on Chinese fossil plants. The majority of these fossils are distinct from fossil floras known from other geographical regions. However, remarkably few of these fossil plants have been successfully incorporated into cladistic analyses, to assess their importance on evolutionary relationships among major plant groups. For the first time our investigation incorporates three endemic Chinese fossil plant species into a cladistic analysis of the seed plants. These plants have been documented and reconstructed in detailed investigations of Palaeozoic coal balls from the Taiyuan Formation and are named Shanxioxylon sinensis , Shanx-ioxylon taiyuanensis and Pennsylvanioxylon tianii respectively. Previous investigations indicate that these plants belong to the now extinct Cordaitalean seed plants although they share many features with certain fossil conifers. As such, they are likely to be of significance to the ongoing and currently unresolv

关键词： phytogeny evolution coniferophyte Coniferales Cordaitales

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Woody plant assemblage and the structure of miombo woodland along a disturbance gradient in Hurungwe, Zambezi Valley, Zimbabwe

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Journal of Forestry Research 2021年第5期32卷 1867-1877页

作者： Tatenda Gotore hilton GTNdagurwa Shakkie Kativu Denis Gautier Laurent Gazull Forest Research Centre P.O.Box HG595HighlandsHarareZimbabwe Department of Forest Resources and Wildlife Management Faculty of Applied ScienceNational University of Science and TechnologyP.O.Box AC 939 AscotBulawayoZimbabwe School of Animal Plant and Environmental SciencesUniversity of the WitwatersrandPrivate Bag 3Wits 2050South Africa Department of Biological Sciences Faculty of ScienceUniversity of ZimbabweP.O.Box MP167 Mount PleasantHarareZimbabwe Forêt et Sociétés Univ MontpellierCIRADTA C-105/DCampus international de Baillarguet34398 Montpellier Cedex 5France

Miombo woodlands near human settlements are under significant pressures from human activities,with negative consequences on their structure and *** studies are limited,we assessed the structure and species composition of a portion of miombo woodland along an increasing disturbance gradient from a national park,through a buffer zone to communal lands in northeast *** concentric plots of 2 and 11 m radii were established in each area to record woody species composition,diameter,height,basal area,density and volume as well as evidence of *** of site,growth stage and their interaction on vegetation diversity and structural parameters were tested using a general linear model(GLM).Principal component analysis(PCA) tested the association between species and site and ANOVA the differences in the level of disturbance across *** diversity did not differ between sites except for evenness,which increased with *** and richness were greater in seedlings and saplings than mature trees across sites,*** and mature tree diameters differed significantly between *** and density of mature trees declined with increasing disturbance while seedling densities peaked at intermediate disturbance levels(buffer zone).Tree harvesting,was more evident in the buffer zone and in the communal area relative to the national *** contrast,fire frequency was greater in the national park and in the buffer zone relative to the communal *** results of this study identify a true miombo woodland dominated by Brachystegia boehmii with a stable population,as illustrated by an inverse-J shape in diameter class distribution on all sites,and that these woodlands are generally resilient to disturbances,maintaining similar species composition and structure at various levels of ***,continued monitoring of disturbance levels and miombo woodland response is recommended to ensure sustainable utilisation of

关键词： Miombo woodlands cComposition Diversity Structure Anthropogenic disturbances

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