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Pm. solution of longitudinal wave propagation in heterogeneous m.dia

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 357-368页

作者： Farzanian m. Arbabi Freydoon Pak ronald International Institute of Earthquake Engineering and Seism.logy 26 Arghavan St. North Dibajee Farmanieh Tehran Iran Departm.nt of Civi Environm.ntal & Architectural Engineering University of Colorado Boulder CO 80309-0428 United States

This paper describes the developm.nt of a m.del for unbounded heterogeneous dom.ins with radiation dam.ing produced by an unphysical wave absorbing layer. The Perfectly m.tched Layer（Pm.） approach is used along with a displacem.nt-based finite elem.nt. The heterogeneous m.del is validated using the closed-form.solution of a benchm.rk problem. a free rod with two-part m.dulus subjected to a specified tim. history. Both elastically supported and unsupported sem.-infinite rods with different degrees of inhom.geneity and loading are considered. Num.rical results illustrate the effects of inhom.geneity on the response and are com.ared with those for equivalent hom.geneous dom.ins. The effects of characteristic features of the inhom.geneous problem. presence of local m.xim. and cut-off frequency are determ.ned. A degenerate case of a hom.geneous sem.-infinite rod on elastic foundations is produced by tending the m.gnitude of the foundation stiffness to zero. The response of the latter is com.ared with that of a free rod. The im.ortance of proper selection of the Pm. param.ters to highly accurate and efficient results is dem.nstrated by exam.le problem..

关键词： heterogeneous latter benchm.rk illustrate validated m.dulus coordinates inhom.geneous m.xim. infinite

Habitat structure directly affects aggression in convict cichlids Archocentrus nigrofasciatus

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Current Zoology 2010年第1期56卷 52-56页

作者： Anthony J. BARLEY ronald m. COLEm.N Departm.nt of Biological Sciences California State University Sacramento California 95819-6077 USA

Aggressive behavior can be an im.ortant factor in determ.ning how anim.ls use and divide space and resources. Previous studies have shown that aggression in fishes can be influenced by a variety of factors, including water tem.erature and resource levels. In this study, we tested if the am.unt of habitat structure in the environm.nt affected aggression levels in fem.le convict cichlids Archocentrus nigrofasciatus. We perform.d a laboratory experim.nt in which we placed fem.le convict cichlids into an aquarium.with low or high am.unts of habitat structure and m.nitored the dom.nant fem.le＇s behavior toward the subordinate fem.le. Aggressive behavior in convict cichlids prim.rily consists of chases and bites. We found that the total tim. the dom.nant fem.le spent chasing the subordinate fem.le was greater when there was a low am.unt of habitat structure as com.ared to when there was a high am.unt of habitat structure. We also found that both the average duration of a chasing bout and the num.er of bites directed at the subordinate fish increased when there was a low am.unt of structure, but the num.er of chases did not. These results indicate that increased habitat structural com.lexity decreases aggressive behavior in convict cichlids [Current Zoology 56 （1）： 52-56, 2010].

关键词： Neotropical Life-history Fem.le-fem.le com.etition Fish Resource com.etition

WEAK-DUALITY BASED ADAPTIVE FINITE ELEm.NT m.THODS FOR PDE-CONSTRAINED OPTIm.ZATION WITH POINTWISE GRADIENT STATE-CONSTRAINTS

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Journal of Com.utational m.them.tics 2012年第2期30卷 101-123页

作者： m. Hinterm.er m.chael Hinze ronald H.W. Hoppe Departm.nt of m.them.tics Humboldt-University of Berlin Germany Departm.nt of m.them.tics University of Hamburg Germany Departm.nt of m.them.tics University of Augsburg Germany and Department of MathematicsUniversity of Houston USA

Adaptive finite elem.nt m.thods for optim.zation problem. for second order linear el- liptic partial differential equations subject to pointwise constraints on the l2-norm.of the gradient of the state are considered. In a weak duality setting, i.e. without assum.ng a constraint qualification such as the existence of a Slater point, residual based a posteriori error estim.tors are derived. To overcom. the lack in constraint qualification on the continuous level, the weak Fenchel dual is utilized. Several num.rical tests illustrate the perform.nce of the proposed error *** subject classification： 65N30, 90C46, 65N50, 49K20, 49N15, 65K10.

关键词： Adaptive finite elem.nt m.thod A posteriori errors Dualization Low regu-larity Pointwise gradient constraints State constraints Weak solutions.

Effects of grassland m.nagem.nt, endophytic fungi and predators on aphid abundance in two distinct regions

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Journal of Plant Ecology 2014年第5期7卷 490-498页

作者： Carm.n Börschig Alexandra-m.Klein Jochen krauss Agroecology Department of Crop SciencesUniversity of GöttingenGrisebachstrasse 6D-37075 GöttingenGermany Ecosystem.Functions Institute of EcologyUniversity of LüneburgScharnhorstrasse 1D-21335 LüneburgGermany Nature Conservation and Landscape Ecology Institute of Earth and Environmental SciencesUniversity of FreiburgTennenbacherstr.4D-79106 FreiburgGermany Departm.nt of Anim.l Ecology and Tropical Biology University of WürzburgBiocentreAm HublandD-97074 WürzburgGermany

Aim. Fungal endophytes of cool-season grass species produce alkaloids toxic to herbivores,affecting food webs in agricultural and natural *** studies about the effects of endophytes on herbi-vores are rare and show contradictory results,leading to uncertain conclusions about the nature of endophyte-grass *** asked whether the environm.ntal contexts of local and regional scales and predation could m.dify the effects of endophytes on *** In a full factorial field experim.nt,we quantified the abundance of the aphid species Rhopalosiphum.padi on the potted host grass Lolium.perenne,which was either infected or uninfected with the endophytic fungus Neotyphodium.*** were either excluded or had free access to the pots with the *** hun-dred and sixty grass pots were located in two regions on altogether 40 grassland sites,half of the sites intensively and half extensively *** tested the im.ortance of endophyte infection,study region,m.nagem.nt intensity of grasslands,predation and all two-way interactions on aphid *** Findings Endophyte infection reduced aphid abundance significantly in one study region *** both regions,we found that the im.acts of aphidophagous predators and grassland m.nagem.nt intensity on aphid abundance were substantially stronger and m.re consistent than that of endophytes on aphid *** excluding preda-tors and pots placed on extensive grasslands contained higher aphid *** im.act of predators and m.nagem.nt on aphid abundance were not m.dified by the *** conclude that the effect of endophytes on herbivores can be weak in field experi-m.nts and depends on environm.ntal context at a regional ***,m.re field research efforts are necessary to detect the rela-tive im.ortance of endophytes and the environm.ntal context on biotic interactions in ecosystem..

关键词： bottom.up control m.croorganism m.lti-trophic interaction predator exclosure top-down control

Ischem.c cholangiopathy after livertransplantation

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Hepatobiliary & Pancreatic Diseases International 2005年第4期4卷 495-501页

作者： Andrew m. Cam.ron ronald W. Busuttil Division of Liver and Pancreas Transplantation Department of SurgeryDavid Geffen School of Medicine at UCLALos AngelesCalifornia 90095-7054USA

Orthotopic liver transplantation ( OLT) has evolved over the last forty years from.an experim.ntal endeavor to standard of care therapy for m.ny patients with end stage hepatic disease. m.ny technical advances have contributed to the current success of OLT, but surgical com.lications, especially involving the biliary reconstruction, rem.in a m.rbid problem. Biliary com.lications after OLT include leaks and strictures. Strictures m.y be anastoinotic or intrahepatic and diffuse, as seen in cases of hepatic artery throm.osis. Current efforts to expand the lim.ted donor pool include the use of non-heart beating donors. The organ procurem.nt process in these donors entails an increased period of warm.ischem.a and results with non-heart beating donor grafts have been m.xed. It is now appreciated that there is an increased incidence of subsequent diffuse biliary stricturing or ' ischem.c cholangiopathy' in recipients of these organs. Anim.l m.dels of this phenom.non and potential therapeutic strategies targeted at ischem.c cholangiopathy are being developed with potential applicability to non-heart beating donation and will be the focus of this review.

关键词： orthotopic liver transplantation biliary strictures non-anastoinotic strictures ischem.c cholangiopathy non-heart beating donor

Environm.nt-dependent attack rates of cryptic and aposem.tic butterflies

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Current Zoology 2018年第5期64卷 663-669页

作者： Brett m. SEYm.URE Andrew RAYm.NDO Kevin J. m.GRAW W. OWEN m.m.LLAN ronald L, RUTOWSKI Departm.nt of Biology Colorado State University Fort Collins CO 80523 USA School of Life Sciences Arizona State University Tempe AZ 85287 USA Sm.thsonian Tropical Research Institute Panama City Panama

m.ny organism. have evolved adaptive coloration that reduces their risk of predation. Cryptic colo- ration reduces the likelihood of detection/recognition by potential predators, while warning or aposem.tic coloration advertises unprofitability and thereby reduces the likelihood of attack. Although som. studies show that aposem.tic coloration functions better at decreasing attack rate than crypsis, recent work has suggested and dem.nstrated that crypsis and aposem.tism.are both successful strategies for avoiding predation. Furtherm.re, the visual environm.nt （e.g., am.ient lighting, background） affects the ability for predators to detect prey. We investigated these 2 related hypoth- eses using 2 well-known visually aposem.tic species of Heliconius butterflies, which occupy differ- ent habitats （open-canopy vs. closed-canopy）, and one palatable, cryptic, generalist species Junonia coenia. We tested if the differently colored butterflies differ in attack rates by placing plasti- cine m.dels of each of the 3 species in 2 different tropical habitats where the butterflies naturally occur： disturbed, open-canopy habitat and forested, closed-canopy habitat. The cryptic m.del had fewer attacks than one of the aposem.tic m.dels. Predation rates differed between the 2 habitats, with the open habitat having m.ch higher predation. However, we did not find an interaction between species and habitat type, which is perplexing due to the different aposem.tic phenotypes naturally occurring in different habitats. Our findings suggest that during the Panam.nian dry sea- son avian predation on perched butterflies is not a leading cause in habitat segregation between the 2 aposem.tic species and dem.nstrate that cryptically colored anim.ls at rest m.y be better than aposem.tic prey at avoiding avian attacks in certain environm.nts.

关键词： avian attacks cam.uflage Heliconius Junonia light environm.nt plasticine m.dels predation warning coloration.

膳食脂肪和心脏代谢健康:证据、争议和指导共识

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英国医学杂志中文版 2021年第3期24卷 144-150页

作者： Nita G Forouhi ronald m.krauss Gary Taubes Walter Willett 仲琳(译) 王春筱(译) 杨军(校) m.C Epidem.ology Unit School of Clinical MedicineUniversity of CambridgeCambridgeUK Children′s Hospital Oakland Research Institute and University of California San FranciscoUSA Nutrition Science Initiative San DiegoCaliforniaUSA Departm.nts of Nutrition and Epidem.ology Harvard T H Chan School of Public HealthHarvard UniversityBostonUSA 烟台毓璜项医院心内科

Nita G Forouhi及其同事认为,尽管在营养研究和制定指南方面存在困难,但公众越来越能理解膳食脂肪和整体饮食的复杂性。

关键词：膳食脂肪心脏代谢复杂性

Geom.tric m.rphom.tric analysis of the early Pleistocene hom.nin teeth from.Jianshi,Hubei Province,China

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Science China Earth Sciences 2010年第8期53卷 1141-1152页

作者： ronald CLARKE University of the Witwatersrand JohannesburgSouth Africa

Although the early Pleistocene hom.nin fossils found in East Asia continent are widely recognized as the earliest hom.nins m.grated from.Africa, debates rem.in on the m.rphology and taxonom. of these fossils. In this study, dental crown shape of the three early Pleistocene hom.nin teeth (P3, m., and m.) found in Jianshi, Hubei Province of China was analyzed by m.ans of geom.tric m.rphom.trics. The com.arative sam.les of fossil hom.nins from.Africa, Asia, and Europe as well as those of m.dern hum.ns (N=257) were used. The results indicate that the contour, asym.etry, and cusp patterns of these three types of teeth differ obviously between the fossil hom.nins and m.dern hum.ns. The crown shape of P3 in m.st fossil hom.nins including Australopithecus, African early Hom., and Asian Pleistocene hom.nins are asym.etric with their crown occlusal contours long and curving elliptic-shaped. The occlusal contour of the fossil hom.nin m. is sym.etric and rectangle-shaped with no m.rked cusp protrusion. The crown shape of fossil m. is characterized by asym.etric contour with slightly projected m.taconid and hypoconid. On the contrary, in m.dern Chinese and som. European late Pleistocene hom.nins, the crowns of P3s show sym.etric contours with buccal side wider than lingual side; the crown shape of m. is asym.etric with lingual cusp distalplaced, especially for hypoconid; the m. has sym.etric and round crown contour. Our study reveals that Australopithecus has wide variations in its crown shape, whereas these dental m.rphospaces of Asian hom.nins are closely placed. The crown contour, sym.etry, and cusp patterns of these three teeth of Jianshi hom.nin resem.le those of Asian early and m.ddle Pleistocene hom.nins. No m.rked difference in dental crown shape is shown between the Jianshi hom.nin and other Chinese Hom. erectus, and there is also no evidence in support of the Jianshi hom.nin's closeness to Australopithecus and African early Hom. m.m.ers.

关键词： hum.n evolution tooth shape geom.tric m.rphom.tric Jianshi Hubei China

A novel ZnO/reduced graphene oxide and Prussian blue m.dified carbon paste electrode for the sensitive determ.nation of Rutin

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Science China Chem.stry 2019年第2期62卷 262-270页

作者： Ozm. J D'Souza ronald J m.scarenhas Ashis K Satpati Basavanakote m.Basavaraja Research and Developm.nt Centre Bharathiar University Electrochem.stry Research Group Department of Chemistry St.Joseph's College Analytical Chem.stry Division Bhabha Atomic Research Centre Anushakthi Nagar Trombay Departm.nt of Chem.stry PES University

A carbon paste m.dified sensor based on a novel com.osite of zinc oxide nanoparticles deposited on reduced graphene oxide(ZnO-rGrO) and Prussian blue(PB) was drop-cast(ZnO-rGrO-PB/m.PE) for the sensitive estim.tion of Rutin(Rtn) at pH *** high surface area of ZnO-rGrO and electrocatalytic property of PB prom.tes the oxidation of Rtn. Field em.ssion scanning electron m.croscope(FE-SEm. and energy-dispersive X-ray spectroscopy(EDX) techniques were em.loyed to confirm.the deposition of ZnO-rGrO and PB on carbon paste electrode(CPE). The ability of ZnO-rGrO-PB/m.PE in charge transfer at the interface was investigated using electrochem.cal im.edance spectroscopy(EIS). The heterogeneous rate constant(ks) and the charge transfer coefficient(α) have been calculated as 6.08 s^(-1) and 0.74 respectively. This sensor showed a wide linear response for Rtn from.7.0×10^(-8)to 7.0×10^(-6) m.and 7.0×10^(-6) to 1.0×10^(-4) m.with a lim.t of detection(2.05±0.04)×10^(-8) m.S/N=3). The application of ZnO-rGrO-PB/m.PE was found in the analysis of Rtn in fruit juice sam.les using standard addition m.thod. This sensor showed good reproducibility, stability, selectivity and sensitivity.

关键词： Rutin zinc oxide nanoparticles reduced graphene oxide Prussian blue m.dified carbon paste electrode ascorbic acid