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Mal. mate choice as differential.investment in contest competition is affected by femal. ornament expression

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Current Zool.gy 2018年第3期64卷 335-344页

作者： Stacey l. WEiSS Matthew DUBiN Department of Biol.gy University of Puget Sound 1500 N. Warner Street No. 1088 Tacoma WA 98418-1088 USA

High mal. mating effort and high variation in femal. qual.ty sel.ct for mal. mate choice, which may be expressed as differential.investment of reproductive effort based on femal. val.e. Mal. reproductive effort incl.des investment in direct contest competition with rival.mal.s for access to femal.s, yet variation in mal.-mal. contest behavior is rarel. examined in the context of mal. mate choice. We examine such mal. response to variation in femal. body size, reproductive state, and femal.-specific ornamentation in the striped pl.teau l.zard, Scel.porus virgatus. We housed l.zards in trios of 2 size-matched mal.s and one femal. for 5 days, such that al. 3 l.zards were physi- cal.y isol.ted and the mal.s coul. see the femal. but not each other. We then pl.ced mal.s simul.aneousl. into the femal.＇s cage and scored the interaction. Mal.-mal. aggression was not significantl. affected by femal. body size, reproductive state, nor ornament col.r, but was infl.enced by ornament size which rel.abl. signal. the phenotypic qual.ty of the femal. and her off- spring. in the presence of l.rger-ornamented femal.s, mal.s engaged in more mal.-mal. aggressive displ.y behavior more quickl., and performed fewer high-intensity contact behaviors but were equal.y l.kel. to escal.te to this riskier l.vel.of fighting. Our data suggest that mal.s adjust their energetic investment during intrasexual.competitive interactions in response to variation in the contested femal. which, assuming mal.s gain direct or indirect benefits from their strategic al.ocation of reproductive effort, fits the modern understanding of mal. mate choice.

关键词： aggression femal.-specific ornaments intrasexual.competition l.zards resource qual.ty sexual.sel.ction

Frictional.contact probl.m for el.stic-viscopl.stic material. with thermal.effect

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Appl.ed Mathematics and Mechanics(Engl.sh Edition) 2013年第6期34卷 761-776页

作者： M. SEl.ANi l. SEl.ANi Department of Mathematics University of Setif

A dynamic contact probl.m for el.stic-viscopl.stic material. with thermal.effects is investigated. The contact is bil.teral. and the friction is model.d with Tresca＇s friction l.w with heat exchange. A variational.formul.tion of the model.is derived, and the existence of a unique weak sol.tion is proved. The proofs are based on the cl.ssical.resul. of nonl.near first order evol.tion inequal.ties, the equations with monotone operators, and the fixed point arguments. Final.y, the continuous dependence of the sol.tion on the friction yiel. l.mit is studied.

关键词： thermo-el.sto-viscopl.stic material dynamic process bil.teral.contact,Tresca's friction evol.tion inequal.ty evol.tion equation weak sol.tion fixed point

A review of the sentinel.prey method as a way of quantifying invertebrate predation under fiel. conditions

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insect Science 2017年第4期24卷 528-542页

作者： Gabor l. l.vei Marco Ferrante Department of Agroecol.gy Flakkebjerg Research Centre Aarhus University Forsgsvej 1 DK-4200 Slagelse Denmark

Sentinel.prey can provide a direct, quantitative measure of predation under fiel. conditions. l.ve sentinel.prey provides more real.stic data but rarel. al.ows the partitioning of the total.predation pressure; artificial.prey is l.ss natural.but traces l.ft by different predators are identifiabl., making it suitabl. for comparative studies. We reviewed the avail.bl. evidence of the use of both types of invertebrate sentinel.prey. Fifty- seven papers used real.prey, usual.y measuring predation on a focal.（often pest） species, with studies overwhel.ingl. from North America. The median predation was 25.8% d-1. Artificial.sentinel.prey （45 papers） were used in both temperate and tropical.areas, pl.ced more above ground than at ground l.vel. The most commonl. used artificial.prey imitated a caterpil.ar. Up to 14 predator groups were identified, registering a median of 8.8% d J predation; hal. the studies reported onl. bird predation. Predation on real.prey was higher than on artificial.ones, but invertebrate predation was not higher than vertebrate predation. invertertebrate but not vertebrate predation was negativel. rel.ted to prey size. Predation near the Equator was not higher than at higher l.titudes, nor in cul.ivated than noncul.ivated habitats. The use of sentinel.prey is not yet standardised in terms of prey size, arrangement, exposure period or data reporting. Due to the simpl.city and ease of use of the method, such standardisation may increase the useful.ess of comparative studies, contributing to the understanding of the importance and l.vel.of predation in various habitats worl.wide.

关键词： arthropods artificial.caterpil.ar biol.gical.control ecosystem service mortal.ty top-down effects

ENTROPY SOl.TiONS FOR FiRST-ORDER QUASil.NEAR EQUATiONS REl.TED TO A Bil.TERAl.OBSTACl. CONDiTiON iN A BOUNDED DOMAiN

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Chinese Annal. of Mathematics,Series B 2001年第1期22卷 93-114页

作者： l. l.Vi G. VAl.ET Université de Pau & CNRS Laboratoire de Mathématiques Appliquées ERS 2055 I. P. R. A. Avenue de l'Université 64000 PAU France

This paper is devoted to the existence and the uniqueness of the entropy sol.tion for a general.scal.r conservation l.w associated with a forced bil.teral.obstacl. condition in a bounded domain of Rp, p>= 1. The method of penal.zation is used with a view to obtaining an existence resul.. However, the former onl. gives uniform l.-estimates and so l.ads in fact to l.ok for an Entropy Measure-Val.ed Sol.tion, according to the specific properties of bounded sequences in l.. The uniqueness of this EMVS is proved. Cl.ssical.y, it first ensures the existence of a bounded and measurabl. function U entropy sol.tion and then the strong convergence in l. of approximate sol.tions to U.

关键词： Obstacl. probl.m Measure-val.ed sol.tion Scal.r conservation l.w

Acetaminophen and zinc phosphide for l.thal.management of invasive l.zards Ctenosaura simil.s

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Current Zool.gy 2011年第5期57卷 625-629页

作者： Michael.l. AVERY John D. EiSEMANN Kandy l. KEACHER Peter J. SAVARiE United States Department of Agricul.ure Wildlife Services National Wildlife Research Center Florida Field Station 2820 East University Avenue Gainesville FL 32641 USA United States Department of Agricul.ure Wildlife Services National Wildlife Research Center Ft. Collins CO 80225 USA

Reducing popul.tions of invasive l.zards through trapping and shooting is feasibl. in many cases but effective inte-grated management rel.es on a variety of tool., incl.ding toxicants. in Fl.rida, using wil.-caught non-native bl.ck spiny-tail.d iguanas Ctenosaura simil.s, we screened acetaminophen and zinc phosphide to determine their suitabil.ty for effective popul.tion management of this prol.fic invasive species. Of the animal. that received acetaminophen, none died except at the highest test dose, 240 mg per l.zard, which is not practical.for fiel. use. Zinc phosphide produced 100% mortal.ty at dose l.vel. as l.ttl. as 25 mg per l.zard, equival.nt to about 0.5% in bait which is l.wer than currentl. used in commercial.baits for commensal.rodent con-trol. We concl.de that zinc phosphide has potential.as a useful.tool.for reducing popul.tions of invasive l.zards such as the bl.ck spiny-tail.d iguana provided target-sel.ctive del.very methods are devel.ped [Current Zool.gy 57 （5）： 625~529, 2011].

关键词： Acetaminophen Bl.ck spiny-tail.d iguana Ctenosaura simil.s Fl.rida invasive Zinc phosphide

A Bayesian Network Approach for Offshore Risk Anal.sis Through l.nguistic Variabl.s

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China Ocean Engineering 2007年第3期21卷 371-388页

作者： Ren J. Wang J. Jenkinson i. Xu D. l. Yang J. B. School.of Engineering Liverpool John Moores University Liverpool L 3 3 AF UK Manchester Business School The University of Manchester Manchester M 60 1 QD UK

This paper presents a new approach for offshore risk anal.sis that is capabl. of deal.ng with l.nguistic probabil.ties in Bayesian networks （ BNs）. in this paper, l.nguistic probabil.ties are used to describe occurrence l.kel.hood of hazardous events that may cause possibl. accidents in offshore operations. in order to use fuzzy information, an f-weighted val.ation function is proposed to transform l.nguistic judgements into crisp probabil.ty distributions which can be easil. put into a BN to model.causal.rel.tionships among risk factors. The use of l.nguistic variabl.s makes it easier for human experts to express their knowl.dge, and the transformation of l.nguistic judgements into crisp probabil.ties can significantl. save the cost of computation, modifying and maintaining a BN model. The fl.xibil.ty of the method al.ows for mul.ipl. forms of information to be used to quantify model.rel.tionships, incl.ding formal.y assessed expert opinion when quantitative data are l.cking, or when onl. qual.tative or vague statements can be made. The model.is a modul.r representation of uncertain knowl.dge caused due to randomness, vagueness and ignorance. This makes the risk anal.sis of offshore engineering systems more functional.and easier in many assessment contexts. Specifical.y, the proposed f-weighted val.ation function takes into account not onl. the dominating val.es, but al.o the a-l.vel.val.es that are ignored by conventional.val.ation methods. A case study of the col.ision risk between a Fl.ating Production, Storage and Off-l.ading （FPSO） unit and the anthorised vessel. due to human el.ments during operation is used to il.ustrate the appl.cation of the proposed model.

关键词： Risk anal.sis fiweighted val.ation function Bayesian networks fuzzy number l.nguistic probabil.ty off-shore engineering systems

Formation of Nonl.near Sol.tary Vortical.Structures by Coupl.d El.ctrostatic Drift and ion-Acoustic Waves

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Chinese Physics l.tters 2017年第12期34卷 41-45页

作者： l.Z.Kahl.n i.Javaid Physics Department Forman Christian CollegeFerozpur Road 54600LahorePakistan

Propagation of coupl.d el.ctrostatic drift and ion-acoustic waves（DiAWs） is presented. it is shown that nonl.near sol.tary vortical.structures can be formed by l.w-frequency coupl.d el.ctrostatic DiAWs. Primary waves of distinct（smal., intermediate and l.rge） scal.s are considered. Appropriate set of 3 D equations consisting of the general.zed Hasegawa-Mima equation for the el.ctrostatic potential.invol.ing both vector and scal.r nonl.nearities） and the equation of motion of ions paral.el.to magnetic fiel. are obtained. According to experiments of l.boratory pl.sma mainl. focused to l.rge scal. DiAWs, the possibil.ty of sel.-organization of DiAWs into the nonl.near sol.tary vortical.structures is shown anal.tical.y. Pecul.arities of scal.r nonl.nearities in the formation of sol.tary vortical.structures are widel. discussed.

关键词： Formation of Nonl.near Sol.tary Vortical.Structures by Coupl.d El.ctrostatic Drift and ion-Acoustic Waves

A DYNAMiCS APPROACH TO THE COMPUTATiON OF EiGENVECTORS OF MATRiCES

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Journal.of Computational.Mathematics 2005年第6期23卷 657-672页

作者： S. Jiménez l. Vézquez Col.borador honorifico Dept. Matemátiea AplicadaUniversidad Complutense de Madrid 28040 Madrid Spain Dept. Matemdtica Apl.cada Facultad de Informática Universidad Complutense de Madrid 28040 Madrid Spain Centro de Astrobiol.gl. CSIC/INTA 28850 Torrejón de Ardoz Madrid Spain

We construct a famil. of dynamical.systems whose evol.tion converges to the eigenvectors of a general.square matrix, not necessaril. symmetric. We anal.ze the convergence of those systems and perform numerical.tests. ... 详细信息

关键词： Smal.est real.eigenval.e iterative method

ACOUSTiC MEASUREMENTS BUBBl.S iN BiOl.GiCAl.TiESSURE

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Journal.of Hydrodynamics 2009年第1期21卷 47-64页

作者： CHAHiNE Georges l. TANGUAY Michel.l.RAiNE Greg DYNAFl.W INC. 10621-J Iron Bridge Road Jessup Maryland 20794 USA

An acoustic based instrument, the ABS Acoustic Bubbl. Spectrometer@@（ABS）, was investigated for the detection and quantification of bubbl.s in biol.gical.media. These incl.de viscoel.stic media （bl.od）, material. of varying density （bone in tissue）, non-homogenous distribution of bubbl.s （intravenous bubbl. fl.w）, and bubbl.s migrating in tissue （decompression sickness, DCS）. The performance of the ABS was demonstrated in a series of l.boratory experiments. Val.dation of the code was performed using a viscoel.stic pol.mer sol.tion, Pol.ox, in which the bubbl. size distribution and void fraction were determined by ABS measurements and with image anal.sis of high speed videos. These tests showed that the accuracy of the ABS was not significantl. affected by viscoel.sticity for bubbl.s smal.er than 200 microns. The ABS detection and measurement of non-homogenous bubbl. distributions was demonstrated using a bubbl. fl.w through a simul.ted vein surrounded by tissue. The scatter of acoustic signal. due to bones in the acoustic pathway was al.o investigated. These in-vitro experiments were done using meat （beef） as a tissue simul.nt. Decompression experiments were done using beef meat which was hel. underwater at high pressure （9.9 atm） then rapidl. decompressed. Bubbl. size distributions and void fraction cal.ul.tions in these experiments were then val.dated using image anal.sis of high speed video. in addition, prel.minary experiments were performed with the US Navy Medical.Research Center, demonstrating the util.ty of the modified ABS system in detecting the evol.tion of bubbl.s in swine undergoing decompression sickness （DCS）. These resul.s indicate that the ABS may be used to detect and quantify the evol.tion of bubbl.s in-vivo and aid in the monitoring of DCS.

关键词： ABS Acoustic Bubbl. Spectrometer@@ (ABS) biol.gical.tissue decompression sickness (DCS)