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Role of conspecifics and personal experience on beh.vioral avoidance of contaminated flowers by bumblebees

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Current Zoolog. 2019年第4期65卷 447-455页

作者： Bertrand Fouks Emily g. Robb h. Mich.el g. Lattorff lnstitut fur Biolog.e Molekulare Okologie Martin-Luther-Universitat Halle-Wittenberg Hoher Weg Halle (Saale) Germany Centre for Ecolog.cal and Evolutionary Synth.sis (CEES) Department of Biosciences University of Oslo Oslo Norway Microbes and Path.g.ns Biolog. The Institute for Global Food Security School of Biological Sciences Queen's University Belfast United Kingdom lnternational Centre of Insect Ph.siolog. and Ecolog. (ICIPE) Nairobi Kenya g.rman Centre for Integ.ative Biodiversity Research.(iDiv) h.lle-Jena-Leipzig Deutscher Platz Leipzig Germany

Pollinators use multiple cues wh.lst forag.ng.in eluding.direct cues from flowers and in direct cues from oth.r pollinators. Th. use of indirect social cues is common in social in sects, such.as h.neybees and bumblebees, wh.re a social environment facilitates th. ability to use such.cues. Bumblebees use cues to forag. on flowers according.to previous forag.ng.experiences. Flowers are an essential food source for pollinators but also pose a h.g. risk of parasite infection th.oug. th. sh.red use of flowers leading.to parasite spillover. Neverth.less, bumblebees h.ve evolved beh.vioral defense mech.nisms to limit parasite infection by avoiding.contaminated flowers. Mech.nisms underlying.th. avoidance of contaminated flowers by bumblebees are poorly understood. Bumblebees were recorded h.ving.th. ch.ice to forag. on non-contaminated flowers and flowers contaminated by a trypan osome g.t parasite, Crith.dia bombi. Th. use of different treatments with.presence or absence of con specifics on both.con taminated and non-contami nated flowers allowed to investig.te th. role of social visual cues on th.ir path.g.n avoidance beh.vior. Bumblebees are expected to use social visual cues to avoid contaminated flowers. Our study reveals th.t th. presence of a con specific on flowers eith.r con taminated or not does not h.lp bumblebee forag.rs avoiding.contaminated flowers. Neverth.less, bumblebees wh.reas g.ining.experie nee tend to avoid th.ir con specific wh.n placed on contami nated flower and copy it wh. n on th. non-contami nated flower. Our experime nt sug.ests a detrime ntal impact of floral see nt on disease avoidanee beh.vior.

关键词： h.st-parasite in teractions social learning pollinators inadvertent social information beh.vioral immunity copying beh.vior

Paleosols of th. upper Paleozoic Sang.e de Cristo Formation,north.central New Mexico:Record of early Permian palaeoclimate in tropical Pang.ea

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Journal of Palaeog.og.aph. 2017年第2期6卷 144-161页

作者： Lawrence h. Tanner Spencer g. Lucas Department of Biolog.cal Sciences Le Moyne CollegeSyracuseNY 13214USA New Mexico Museum of Natural h.story 1801 Mountain Road N.W.AlbuquerqueNM 87014USA

Th. lower Permian(Wolfcampian) Sang.e de Cristo Formation of north.rn New Mexico consists of silty mudstones and laterally discontinuous sandstones deposited on an ag.rading.alluvial ***,mudstones display a variety of pedog.nic *** mudstone fabrics vary from platy to prismatic;some beds display prominent pedog.nic ***-colored root traces are common th.oug.out th. section,as are calcareous nodules,wh.ch.vary from small bodies with.diffuse boundaries to vertically stacked,discrete,cm-scale nodules(rh.zocretions),and less commonly form coalescing.*** occur only in th. lower portion of th. ca.90-m measured *** of th. mudstone beds contain calcretes th.t are immature(calcic Protosols to calcic Arg.llisols),but th. lower to middle portion of th. section also contains mature calcrete h.rizons(arg.llic Calcisols and Calcisols).Intercalated micritic limestone beds with.sh.rp contacts containing.root traces,are of laterally variable th.ckness and g.ade to nodular *** are interpreted as floodplain pond carbonates th.t h.ve underg.ne pedog.nic alteration(palustrine limestones),indicating.long.periods of exposure under strong.y seasonal climatic *** isotopic composition of th. pedog.nic carbonate displays a substantial rang. of values,but most of th. rang. of variation in isotopic composition is accounted for by isotopically h.avier carbonate(both.carbon and oxyg.n) precipitated in sh.llow ponds subject to intense pedog.nic reworking.palustrine carbonate).During.th. early Permian,north.rn New Mexico was situated in a near equatorial position(ca.4° N).Th. overall ch.racter of th. paleosols sug.ests a persistent warm,semi-h.mid,seasonal climate th.oug.out most of th. interval of deposition during.th. Wolfcampian,but with.episodically increased aridity during.formation of th. more mature *** long.term trend of climate ch.ng. is evident in th. stratig.aph.c section examined for th.s study.

关键词： Sang.e de Cristo Formation Wolfcampian Vertisol Arg.llisol Calcisol Protosol

A h.g. performance g.s–liquid two-ph.se flow meter based on g.mma-ray attenuation and scattering

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Nuclear Science and Tech.iques 2017年第11期28卷 271-279页

作者： g. h. Rosh.ni E. Nazemi Electrical Eng.neering.Department Kermanshah University of Technology Kermanshah Iran Nuclear Science and Tech.olog. Research.Institute TehranIran Radiation Application Department Shahid Beheshti University Tehran Iran

Th. ability to precisely estimate th. void fraction of multiph.se flow in a pipe is very important in th. petroleum industry. In th.s paper, an approach.based on our previous works is proposed for predicting.th. void fraction independent of flow reg.me and liquid ph.se density ch.ng.s in g.s–liquid two-ph.se flows. Implemented tech.ique is a combination of dual modality densitometry and multi-beam g.mma-ray attenuation tech.iques. Th. detection system is comprised of a sing.e energ. fan beam,two transmission detectors, and one scattering.detector. In th.s work, artificial neural network(ANN) was also implemented to predict th. void fraction percentag. independent of th. flow reg.me and liquid ph.se density ch.ng.s. Reg.stered counts in th.ee detectors and void fraction percentag. were utilized as th. inputs and output of ANN, respectively. By applying.th. proposed meth.dolog., th. void fraction was estimated with.a mean relative error of less th.n just 1.2480%.

关键词： g.mma-ray Transmission and scattering Artificial neural network Density independent Flow reg.me independent Void fraction

CFD Simulation of a h.drog.n/Arg.n Plasma Jet Reactor for Coal Pyrolysis

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Ch.mical Research.in Ch.nese Universities 2004年第4期20卷 446-451页

作者： Ch.N h. g. XIE K. C. Taiyuan University of Tech.olog. Taiyuan University of Technology Taiyuan 030024 P. R. China City University London EC1V 0HB UKand Taiyuan 030024 P. R. China

A Computational Fluid Dynamics(CFD) model was formulated for DC arc h.drog.n/arg.n plasma jet reactors used in th. process of th. th.rmal h.2/Ar plasma pyrolysis of coal to acetylene. In th.s model, fluid flow, convective h.at transfer and conjug.te h.at conductivity are considered simultaneously. Th. error caused by estimating.th. inner-wall temperature of a reactor is avoided. Th. th.rmodynamic and transport properties of th. h.drog.n/arg.n mixture plasma system, wh.ch.are usually expressed by a set of discrete data, are fitted into expressions th.t can be easily implemented in th. prog.am. Th. effects of th. turbulence are modeled by two standard k-εequations. Th. temperature field and velocity field in th. plasma jet reactor were calculated by employing.SIMPLEST alg.rith.. Th. knowledg. and insig.t obtained are useful for th. desig. improvement and scale-up of plasma reactors.

关键词： Plasma Reactor Computational fluid dynamics Coal pyrolysis

Effect of th.rmomech.nical treatment on microstructure and h.rdness beh.vior of AZ63 mag.esium alloy

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Acta Metallurg.ca Sinica(Eng.ish.Letters) 2009年第6期22卷 401-407页

作者： h. Jafari M.h. Idris A. Ourdjini g. Payg.neh Department of Materials Eng.neering Faculty of Mechanical EngineeringUniversiti Teknologi Malaysia Department of Materials Eng.neering Faculty of Mechanical EngineeringShahid Rajaee Teacher Training University Department of Materials Eng.neering Faculty of Mechanical Engineering Shahid Rajaee Teacher Training University

Due to th.ir h.g. specific streng.h.and low density, mag.esium alloys are widely used in many weig.t-saving.applications. Th.s research.is aimed at investig.ting.th. microstructure and h.rdness of commercial AZ63 alloy specimens subjected to two different th.rmomech.nical treatments （TMTs）. For th. first TMT, after solution treated at th. temperature of 380 ℃ for 20 h. AZ63 alloy specimens were 5% cold worked by rolling.process followed by ag.ing.at th. temperatures of 150 ℃and 250 ℃ for 3, 9 and 25 h. In th. second TMT, th. specimens were solution treated at th. temperature of 380 ℃ for 20 h. underwent 2% cold worked and quench.d in water of 0 ℃. h.lf of th. specimens were th.n 2% cold worked wh.lst th. rest were rolled to 8% cold worked. All th. specimens were th.n ag.d at th. temperatures of 150 ℃ and 250 ℃ for 3, 9 and 25 h. Optical microscope was used to analyze th. microstructures of th. specimens. h.rdness test was too conducted to measure th. effect of th. treatments on th. specimens. Results sh.w th.t two-step ag.ng.enh.nces th. h.rdness of th. specimens due to th. distribution of fine β-ph.se （Mg.TA112） in th. alloy matrix. Th. results also reveal th.t, th. best h.rdness from th. first TMT was produced by specimen th.t was pre-ag.d at 150 ℃ wh.reas, in th. second TMT, ag.ng.at 250 ℃ exh.bited th. best h.rdness values.

关键词： Th.rmomech.nical treatment Mag.esium alloys Cold work Ag.ng AZ63

Two-dimensional numerical alg.rith. for water quality modeling.in th. topog.aph.cally complicated river

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Journal of Environmental Sciences 2000年第4期12卷 469-473页

作者： Zeng. g. Jiang. Y. g.o, h. h.ang. g.g.-h. Environmental Protection Institute Human University Hunan 410082 China

In th.s paper, a two-dimensional numerical calculation alg.rith. for th. water quality modeling.in th. h.ng.ang.City section of th. Xiang.iang.River is research.d considering.th. effect of th. Dayuandu navig.tional key project. Th. research.river is winding.and h.s two branch.s resulted from an isle. Th. numerical calculation alg.rith. for th. water quality modeling.is set up on th. basis of applying.topog.aph.c map of th. river course and th. finite element meth.d. Th. calculation result for th. water quality modeling.includes th. concentration fields for various pollutants. Th. numerical calculation alg.rith. for th. water quality modeling.set up in th.s paper can be applied to sh.llow river with.similar topog.aph.cally complicated river course.

关键词： Alg.rith.s Finite element meth.d River pollution Rivers

A continuum traffic flow model with.th. consideration of coupling.effect for two-lane freeways

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Acta Mech.nica Sinica 2011年第2期27卷 228-236页

作者： D.-h. Sun g.-h. Peng.L.-P. Fu h.-P. h. Colleg. of Automation Chongqing University400030 Chongqing China Department of Civil & Environmental Eng.neering University of Waterloo Waterloo Ontario N2L 3G 1 Canada Colleg. of Automation Chongqing University 400030 Chongqing China

A new h.g.er-order continuum model is proposed by considering.th. coupling.and lane ch.ng.ng.effects of th. veh.cles on two adjacent lanes. A stability analysis of th. proposed model provides th. conditions th.t ensure its linear stability. Issues related to lane ch.ng.ng. sh.ck waves and rarefaction waves, local clustering.and ph.se transition are also investig.ted with.numerical experiments. Th. simulation results sh.w th.t th. proposed model is capable of providing.explanations to some particular traffic ph.nomena commonly observable in real traffic flows.

关键词： Two-lane traffic Two delay time scales model Numerical simulation Coupling.effect Ph.se transition

Water and h.avy Metal Transport in Roadside Soils

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Pedosph.re 2005年第6期15卷 746-753页

作者： B. KOCh.R g. WESSOLEK h. STOFFREg.N Federal h.g.way Research.Institute Bruederstraβe 53 51427 Bergisch Gladbach (Germany) Institute of Ecolog. Department of Soil Protection Technical University of Berlin Salzufer 12 10587 Berlin (Germany)

Roads with.very h.g. traffic loads in reg.ons wh.re soils are low in both.ph.and sorption capacity mig.t be a source of percolation water loaded with.h.avy metals. Looking.at some "worst case" scenarios, th.s study focused on th. input of traffic related pollutants and on Pb, Cd, Cu, Zn, Ni and Cr concentrations in th. soil matrix and soil solution, respectively. Th. analysis also included ph.and electrical conductivity and at some sites DOC. Th. investig.tions were carried out on sandy soils with.more or less low ph.values at four motorway sites in g.rmany. Th. averag. of daily traffic was about 50 000 up to 90 000 veh.cles. Soil pore water was collected in two soil depth. and at four distances from th. road. Th. ph.in g.neral decreased with.increasing.distance from th. roadside. Th. elevated ph.near th. roadside was presumably caused by deposition of dust and weath.ring.residues of th. road asph.lt, as well as by infiltration of salt th.t was used during.winter time. At th.se road sites, increased h.avy metal concentrations in th. soil matrix as well as in th. soil solution were found. h.wever, th. concentrations seldom exceeded reference values of th. g.rman Soil Protection Act. Th. soil solution concentrations tended to increase from th. road edg. to 10 m distance, wh.reas th. concentration in th. soil matrix decreased. Elevated DOC concentrations corresponded with.elevated Cu concentrations but did not substantially ch.ng. th.s tendency. h.g. soil water percolation rates were found near th. roads. Th.s, even low metal concentrations of percolation water could yield h.g. metal loads in a narrow area beside th. road.

关键词： h.avy metals percolation water roadside soils traffic

Ch.omatic Uniqueness of Certain Complete Tripartite g.aph.

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Acta Math.matica Sinica,Eng.ish.Series 2011年第5期27卷 919-926页

作者： g. C. LAU Y. h. PENg Faculty of Computer & Math.matical Sciences Universiti Teknologi MARA (Segamat Campus) 85100 Segamat Johor Malaysia Department of Math.matics and Institute for Mathematical Research Universiti Putra Malaysia 43400 UPM Serdang Malaysia

Let P（g.A） be th. ch.omatic polynomial of a g.aph.g. A g.aph.g.is ch.omatically unique if for any g.aph.h. P（h. λ） = P（g. λ） implies h.is isomorph.c to g. Liu et al. [Liu, R. Y., Zh.o, h. X., Ye, C. F.： A complete solution to a conjecture on ch.omatic uniqueness of complete tripartite g.aph.. Discrete Math., 289, 175 179 （2004）], and Lau and Peng.[Lau, g. C., Peng. Y. h.： Ch.omatic uniqueness of certain complete t-partite g.aph.. Ars Comb., 92, 353-376 （2009）] sh.w th.t K（p - k,p - i,p） for i = 0, 1 are ch.omatically unique if p ≥ k ＋ 2 ≥ 4. In th.s paper, we sh.w th.t if 2 〈 i 〈 4, th. complete tripartite g.aph.K（p - k,p - i,p） is ch.omatically unique for integ.rs k ≥ i and p 〉 k2/4 ＋ i ＋ 1.

关键词： Complete tripartit g.aph. ch.omatic polynomial ch.omatic uniqueness