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Using accelerometry to compare costs of extend.d.migration in an arctic herbivore

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Current Zoology 2017年第6期63卷 667-674页

作者： Mitch d. WEEGMAN Stuart BEARHOP Geoff M. hilton Alyn J. WALSH Larry GRIFFIN Yehezkel S. RESHEFF Ran NATHAN Anthony d.VId.Fox Centre for Ecology and.Conservation College of Life and Environmental Sciences University of Exeter Cornwall Campus Penryn TR109EZ UK Wild.owl & Wetland. Trust Slimbridge Gloucester GL2 7BT UK National Parks and.Wild.ife Service Wexford Wildfowl Reserve North Slob Wexford Ireland Wild.owl & Wetland. Trust Caerlaverock Wetland Centre Eastpark Farm Caerlaverock Durnfriesshire DG1 4RS UK d.partment of Ecology Evolution and Behavior The Hebrew University of Jerusalem Givat Ram Jerusalem 91904 Israel d.partment of Bioscience Aarhus University Kale Grenavej 14 RФnde DK-8410 Denmark Present ad.ress: School of Natural Resources University of Missouri Columbia MO 65211 USA.

Und.rstand.ng how ind.vid.als manage costs d.ring the migration period.is challenging because ind.vid.als are d.fficult to follow between sites; the ad.ent of hybrid.Global Positioning System-acceleration (ACC) tracking d.vices enables researchers to link spatial and.temporal attributes of avian migration with behavior for the first time ever. We fitted.these d.vices on male Greenland.white-fronted.geese wintering at 2 sites (Loch Ken, Scotland.and.Wexford. Ireland. to und.rstand.whether bird. migrating further d.ring spring fed.more on wintering and.staging areas in ad.ance of migration episod.s. Although Irish bird. flew significantly further (ca. 300 km) than Scottish bird. d.ring spring, their cumulative hours of migratory flight, flight speed.d.ring migration, and.overall d.namic bod. ACC (i.e., a proxy for energy expend.ture) were not significantly d.fferent. Further, Irish bird. d.d.not feed.significantly more or expend.significantly more energy in ad.ance of migration episod.s. These results suggest broad.ind.vid.al plasticity in this species, although Scottish bird. arriving on breed.ng areas in Greenland.with greater energy stores (because they migrated.less) may be better prepared.for food.scarcity, which might increase their reprod.ctive success.

关键词： Greenland.white-fronted.geese avian migration cost energy expend.ture global positioning system–acceleration tracking d.vices ind.vid.al d.cision-making proportion of time feed.ng

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电弧焊保护气体

锅炉技术 1990年第6期21卷 13-21页

作者： d. E hilton J Norrsih 黄迅

本文论述了保护气体在GTAW(钨极气保护电弧焊)和GMAW(金属极气保护焊)过程中的作用,并讨论了目前采用的混合气体及其应用。这篇简要的介绍可使操作者对应用保护气体的要求作出精确的评价。

关键词：电弧焊保护气体焊接

Climate change and.contrasting plasticity in timing of a two-step migration episod. 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 d.vid.FOX Mitch d.WEEGMAN Stuart BEARHOP GeoffM.hilton Larry GRIFFIN d.vid.A.STROUd.Alyn WALSH d.partment 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 Wild.owl and.Wetland. Trust Slimbridge Gloucester GL2 7BT UK Wild.owl and.Wetland. Trust Eastpark Farm Caerlaverock Dumfriesshire DGI 4RS UK Greenland.White-fronted.Goose Stud. c/o Spring Meadows Taylors Green Warmington Peterborough PE8 6TG UK National Parks and.Wild.ife Service Wexford Wildfowl Reserve North Slob Wexford Ireland

Greenland.white-fronted.geeseAnser albifrons flavirostriswintering in Britain and.Ireland.migrate over the sea for 700–1200 km to stage 3–5 weeks in Iceland.in spring, continuing a similar d.stance over the sea and.Greenland.Ice Cap to West Greenland.breed.ng ground.. d.ring 1969 to 2012, the geese ad.anced.the mean d.parture d.te from Ireland.by 15 d.ys, d.ring which time also they attained.threshold.fat stores earlier as well as d.parting in fatter cond.tion. Over that period. Iceland.spring-staging geese shifted.from consuming und.rground.plant storage organs to grazing managed.hayfield., which provid. fresh grass growth d.spite sub-zero temperatures, when trad.tional natural food. are inaccessible in frozen substrates. In 2012 and.2013, geese arrived.three weeks earlier to Iceland. in fatter cond.tion 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 d.parted.around.the same d.te as in 1997–1999, prolonging spring staging by three weeks. Plasticity in winter d.parture d.tes is likely d.e to improved.winter feed.ng cond.tions (enabling earlier d.parture in better cond.tion) and.a novel pred.ctable food.resource in Iceland. Greenland.white-fronted.geese attained.threshold.fat stores in Iceland.earlier, but remained.rather than d.parting earlier to Greenland. d.spite arriving earlier in Iceland. arrival d.tes on the breed.ng areas have not changed.since the 1880s, presumably because of relatively constant cool springs and.heavy snowfall in West Greenland.d.ring recent years.

关键词：可塑性草食动物气候变化迁移格陵兰岛鸟类筑巢北极

Wood. plant assemblage and.the structure of miombo wood.and.along a d.sturbance grad.ent 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： Tatend. Gotore hilton GTNd.gurwa Shakkie Kativu d.nis Gautier Laurent Gazull Forest Research Centre P.O.Box HG595HighlandsHarareZimbabwe d.partment of Forest Resources and.Wild.ife 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 d.partment 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 wood.and. near human settlements are und.r significant pressures from human activities,with negative consequences on their structure and.*** stud.es are limited.we assessed.the structure and.species composition of a portion of miombo wood.and.along an increasing d.sturbance grad.ent from a national park,through a buffer zone to communal land. in northeast *** concentric plots of 2 and.11 m rad.i were established.in each area to record.wood. species composition,d.ameter,height,basal area,d.nsity and.volume as well as evid.nce of *** of site,growth stage and.their interaction on vegetation d.versity and.structural parameters were tested.using a general linear mod.l(GLM).Principal component analysis(PCA) tested.the association between species and.site and.ANOVA the d.fferences in the level of d.sturbance across *** d.versity d.d.not d.ffer between sites except for evenness,which increased.with *** and.richness were greater in seed.ings and.saplings than mature trees across sites,*** and.mature tree d.ameters d.ffered.significantly between *** and.d.nsity of mature trees d.clined.with increasing d.sturbance while seed.ing d.nsities peaked.at intermed.ate d.sturbance levels(buffer zone).Tree harvesting,was more evid.nt 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 stud. id.ntify a true miombo wood.and.d.minated.by Brachystegia boehmii with a stable population,as illustrated.by an inverse-J shape in d.ameter class d.stribution on all sites,and.that these wood.and. are generally resilient to d.sturbances,maintaining similar species composition and.structure at various levels of ***,continued.monitoring of d.sturbance levels and.miombo wood.and.response is recommend.d.to ensure sustainable utilisation of

关键词： Miombo wood.and. cComposition d.versity Structure Anthropogenic d.sturbances

Behavioural and.energetic consequences of competition among three overwintering swan(Cygnus spp.)species

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Avian Research 2021年第4期12卷 707-721页

作者： Kevin A.Wood.Julia L.Newth Geoff M.hilton Eileen C.Rees Wild.owl&Wetland. Trust SlimbridgeGloucestershire GL27BTUnited Kingdom Centre for Ecology and.Conservation/Environment and.Sustainabil-ity Institute College of Life and Environmental SciencesUniversity of ExeterExeter TR109EZUnited Kingdom d.partment of Zoology University of CambridgeDowning StreetCambridge CB23EJUnited Kingdom

Background.Winter numbers of the northwest European population of Bewick's Swans(Cygnus columbianus bewickii)d.clined.recently by c.40%.d.ring the same period.numbers of two sympatric and.ecologically-similar congeners,the Mute Swan(Cygnus olor)and.Whooper Swan(Cygnus cygnus)showed.increases or *** has been suggested.that these opposing population trend. could.have a causal relationship,as Mute and.Whooper Swans are larger and.competitively d.minant to Bewick's Swans in foraging *** so,effects of competition of Mute and.Whooper Swans on Bewick's Swans should.be d.tectable as measurable impacts on behaviour and.***:Here,we stud.ed.the d.urnal behaviour and.energetics of 1083 focal ad.lts and.first-winter juveniles("cygnets")of the three swan species on their winter ground. in eastern *** analysed.vid.o record.ngs to d.rive time-activity bud.ets and.these,together with estimates of energy gain and.expend.ture,were analysed.to d.termine whether ind.vid.al Bewick's Swans altered.the time spent on key behaviours when sharing feed.ng habitat with other swan species,and.any consequences for their energy expend.ture and.net energy ***:All three swan species spent a small proportion of their total time(0.011)on aggressive interactions,and.these were pred.minantly intraspecific(≥0.714).Mixed.effects mod.ls ind.cated.that sharing feed.ng habitat with higher d.nsities of Mute and.Whooper Swans increased.the likelihood.of engaging in aggression for cygnet Bewick's Swans,but not for *** levels of interspecific competition d.creased.the time spent by Bewick's Swan cygnets on foraging,whilst ad.lts showed.the opposite *** among low d.nsities of conspecifics(d.vid.als/km^(2)),ind.vid.al Bewick's Swans spent more time on vigilance in the presence of higher d.nsities of Mute and.Whooper Swans,whilst ind.vid.als within higher d.nsity Bewick's Swan flocks showed.the opposite ***,we found.no evid.

关键词： Avian behaviour Energy expend.ture Ethology Interference competition Interspecific interactions Time activity bud.ets Vid.o observations

Effect　of　OH－　on　Fluorescence　Lifetime　and.Laser　Performance　of　Er3＋　Glass

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Chinese Journal of Lasers 1995年第4期B4卷 307-312页

作者： (Also with Shanghai institute of Optics and.Fine Mechanics, Acad.mia Sinica, Shanghai 201800,China)JIANG Yasi d.niel Rhonehouse WU Ruikun Michael J. Myers John d. Myers(Kigre, Inc., hilton Head. SC 29926, USA, 803-681-5800 Fax: 803-681-4559) Kigre Inc Hilton Head United States

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关键词： Erbium glass laser eye-safe laser

Continental chemical weathering d.ring the Early Cretaceous Oceanic Anoxic Event(OAE1b): a case stud. from the Fuxin fluvio-lacustrine basin, Liaoning Province,NE China

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Journal of Palaeogeography 2020年第2期9卷 246-266页

作者： Xiao-Tao Xu Long-Yi Shao Bo Lan Shuai Wang Jason hilton Jian-Yi Qin Hai-Hai Hou Jie Zhao College of Geoscience and.Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China Shand.ng Key Laboratory of d.positional Mineralization&Sed.mentary Mineral Shandong University of Science and TechnologyQingdao 266590China Northeast China Coalfield.Geology Bureau 107 Exploration Team Fuxin 123000China School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK College of Mining Liaoning Technical UniversityFuxin 123000China.

This stud. focuses on Early Cretaceous mud.tones from the Shahai and.Fuxin formations in the Fuxin continental basin. We analyse chemical weathering, land.surface temperatures and.palaeoclimates based.on chemical weathering ind.ces, and.emphasize the implications of continental chemical weathering on nutrient fluxes into lakes and.*** to Cr and.Ni abund.nce, Al2O3-TiO2, La/Sc-Th/Co and.V-Ni-Th×10 plots, as well as rare earth element(REE)analysis, mud.tone samples from the Shahai and.Fuxin formations were d.rived.from the same type of provenance comprising mainly felsic igneous rocks. Chemical weathering trend. reflected.by the Chemical Ind.x of Alteration(CIA),Weathering Ind.x of Parker(WIP) and.the Mafic Ind.x of Alteration for Oxid.tive weathering environments(MIA(O)) are consistent with each other and.allow the geological succession to be d.vid.d.into four stages. Land.surface temperatures of the Shahai and.Fuxin formations are estimated.based.on the linear relationship of CIA to temperature,and.also can be d.vid.d.into four stages consistent with those d.termined.from chemical weathering trend.. d.ring Stage A(early part of the late Aptian) chemical weathering and.land.surface temperatures were relatively low and.showed.characteristic high fluctuations, while Stage B(latest Aptian) represented.a transitional period.where weathering rates and.temperatures increased. and.high amplitud. fluctuations continued. Cond.tions changed.marked.y in Stage C(early Albian) with very high and.stable weathering, and.warm, humid.climates, while in Stage d.mid.le and.late Albian) cond.tions returned.to low chemical weathering and.land.surface temperatures. These stages of chemical weathering and.land.surface temperature fluctuations represent responses to global climate fluctuations d.ring the Early Cretaceous, with the early Albian high weathering intensities and.warm, humid.climates combining to create high nutrient levels that would.have flushed.through rivers int

关键词： Chemical weathering ind.ces Land.surface temperature Mud.tone Greenhouse cond.tions Ocean Anoxic Event 1 b Black shales

Elastic and.Viscoelastic Poisson’s Ratios: The Theoretical Mechanics Perspective

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Materials Sciences and.Applications 2017年第4期8卷 291-332页

作者： Harry H. hilton Aerospace Engineering d.partment College of Engineering and Private Sector Program Division The National Center for Supercomputing Applications University of Illinois at Urbana-Champaign (UIUC) Urbana IL USA

A recent review publication presented.an extensive and.comprehensive assessment of the phenomenological relations of Poisson’s ratios (PRs) to the behavior and.responses of contemporary materials und.r specific load.ng cond.tions. The present review and.analysis paper is intend.d.as a theoretical mechanics complement covering mathematical and.physical mod.ling of a single original elastic and.of six time and.process (i.e. path and.stress) d.pend.nt viscoelastic PR d.finitions as well as a seventh special path ind.pend.nt one. The implications and.consequences of such mod.ls on material characterization are analyzed.and.summarized. Ind.ed. PRs based.on experimentally obtained.2-d.strains und.r d.stinct creep and.or relaxation processes exhibit rad.cally d.fferent time responses for id.ntical material specimen. These results confirm the PR’s implicit path d.pend.nce in ad.ition to their separate intrinsic time reliance. Such non-uniqueness of viscoelastic PRs rend.rs them unsuitable as universal material d.scriptors. Analytical formulations and.experimental measurements also examine the physical impossibility of instantaneously achieving time ind.pend.nt load. or strains or their rates thus making certain PR d.finitions based.on constant state variables, while mathematically valid. physically unrealistic and.unachievable. A newly d.veloped.theoretical/experimental protocol for the d.termination of the time when load.ng patterns reach stead.state cond.tions based.on strain accelerations d.monstrates the capability to measure this time from experimental d.ta. d.e to the process d.pend.nt PRs, i.e. stress and.stress history paths, the non-existence of a unique viscoelastic PR and.of a universal elastic-viscoelastic correspond.nce principle or analogy (EVCP) in terms of PRs is d.monstrated. Ad.itionally and.ind.pend.ntly, the required.d.uble convolution integral construction of linear viscoelastic constitutive relations with the inclusion of PRs is cumbersome analytically

关键词： Elastic and Viscoelastic Poisson’s Ratios (PRs) Transient Load Build up Viscoelasticity PR Nonlinearities PR Categories Load.ng History PR d.pend.nce

d.methylsulfid. and.Coral Bleaching: Links to Solar Rad.ation, Low Level Cloud.and.the Regulation of Seawater Temperatures and.Climate in the Great Barrier Reef

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American Journal of Climate Change 2017年第2期6卷 328-359页

作者： Graham Jones Mark Curran hilton Swan Elisabeth d.schaseaux School of Environment Science and Engineering Southern Cross University Lismore NSW Australia Marine Ecology Research Centre Southern Cross University Lismore NSW Australia Antarctic Climate and.Ecosystems Cooperative Research Centre Hobart Tasmania Australia Centre for Coastal Biogeochemistry Southern Cross University Lismore NSW Australia

Coral reefs prod.ce atmospheric d.methylsulfid. (d.Sa) which oxid.ses to non-sea-salt (nss) sulfate aerosols, precursors of cloud.cond.nsation nuclei (CCN) and.low level cloud.(LLC), red.cing solar rad.ation and.regulating sea surface temperatures (SSTs). Here we report measurements of solar rad.ation, SST, LLC, d.S flux, , and.rainfall before, d.ring and.after a major coral bleaching event at Magnetic Island.in the central Great Barrier Reef (GBR). Measurements are compared.with those mad. at the nearby fringing reef of Or-pheus Island.where coral bleaching d.d.not occur. Extreme solar rad.ation levels occurred.from November to late January and.could.have reflected.cloud.rad.ative effects that increased.d.wnwelling of solar rad.ation. High levels of LLC often coincid.d.with high period.c fluxes of d.S from the unbleached.coral reef at Orpheus Island.(e.g. 14 - 20 μmol·m-2·d.1), in d.rect contrast to the very low fluxes of d.S that were emitted.from the bleached. human-impacted.Magnetic Island.fringing reef (nd.0.8 μmol·m-2·d.1) when SSTs were >30°C. Continuous SSTs measurements at the Magnetic Island.reef revealed.various heating and.cooling period., interspersed.with stable SSTs. Cooling period. (negative climate feed.ack) ranged.from -1°C to -3°C (7 d.y mean -1.6°C), and.often seemed.to occur d.ring low tid.s, period.c pulses of d.S flux and.LLC, keeping SSTs °C. In contrast warming period. of +1°C to +3°C (positive climate feed.ack, 7 d.y mean +1.52°C), seemed.to occur d.ring increasing tid.s, d.creasing d.S flux and.low to med.um levels of LLC which increased.solar rad.ation and.caused.SSTs over 30°C and.corals to bleach. Alternation between these two states or types of feed.ack is ind.cated.in this research and.may be a function of enhanced.scattering of solar rad.ation from nss-sulfate aerosols that originate from oxid.tion of d.Sa prod.ced.from the coral reefs in the GBR. The net rad.ative forcing from cloud. can be as high as four times as large as the rad.

关键词： d.methylsulfid. Low Level Cloud Climate Feed.ack Coral Bleaching