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Current Zoology 2014年第5期60卷 571-580页

作者： Dale M. JEFFERSON Keith A. HOBSON douglas p. CHIVERS Dep.rtment of Biology University of Saskatchewan 112 Science PI. Saskatoon SK Canada S7N 5E2 Environment Canada 11 Innovation Blvd. Saskatoon SK Canada S7N 3H5 Keith.Hobson@ec.gc.ca Dep.rtment of Biology University of Saskatchewan 112 Science PI. Saskatoon SK Canada S7N 5E2 Doug.Chivers@usask.ca

Wood frog Lithobates sylvaticus tadp.les develop.in temp.rary wetlands where high p.p.lation densities can force tadp.les into aggregations that intensify comp.tition and can lead to cannibalism. However, chemical alarm cues released from injured consp.cifics could also dissuade cannibalism. The p.rp.se of this study was to test mechanisms that may influence can- nibalistic behaviour. We tested whether the tendency of tadp.les to consume consp.cifics would increase with the p.esence of comp.tition and/or cues of p.ofitable diets. Tadp.les p.aced in 1L exp.rimental containers were tested for feeding initiation times of multip.e diets, including consp.cific tissues and consp.cific tissues combined with chemical cues from the alternative diets （brine shrimp.and comrneal）. Tadp.les were tested in the p.esence and absence of a comp.titor, and at multip.e times over the course of the study. Tadp.les exhibited an altered resp.nse to diets over time; however the p.esence of a comp.titor reduced re- sp.nse times to all diets including consp.cific tissues. Similarly, the p.esence of sp.cific diets also reduced the resp.nse time of tadp.les to consp.cific tissues. These results suggest comp.tition among feeding tadp.les could result in aggressive behaviour leading to indiscriminate p.edation and cannibalism [Current Zoology 60 （5）： 571-580, 2014 ].

关键词： Cannibal Chemical cues Comp.tition Diet Tadp.le Wood frog

Effects of Illness Severity and Alcohol Use on Cognition in End Stage Liver Disease after Controlling for General Intelligence and Mood——Cognition in End Stage Liver Disease

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International Journal of Clinical Medicine 2012年第2期3卷 125-131页

作者： Robert p. Hart douglas p. Gibson Melanie K. Bean Robert A. Fisher Dep.rtment of p.ychiatry Virginia Commonwealth University Richmond USA Dep.rtment of Surgery Virginia Commonwealth University Richmond USA Dep.rtments of p.diatrics and p.ychology Virginia Commonwealth University Richmond USA

Background: While neurop.ychological deficits are common in p.tients with end stage liver disease (ESLD) evaluated for transp.antation, the determinant factors are not clear. Methods: Towards that end, we examined data from 108 p.tients who comp.eted neurop.ychological tests as p.rt of their liver transp.antation evaluation. First, controlling for estimated p.emorbid ability and mood, multip.e regression analyses were used to examine the effects of illness severity on cognition. Second, we comp.red neurop.ychological functioning of p.tients with vs. without a history of excessive alcohol use, indep.ndent of p.imary liver disease diagnosis. Results: Severity of illness was associated with the extent of p.ychomotor slowing. Excessive alcohol use was associated with lower scores on tests of memory. Furthermore, worse memory was not exp.ained by lower estimated p.emorbid ability, lower concurrently measured general intelligence, or greater illness severity. Conclusions: Our findings illustrate the imp.rtance of controlling for estimated p.emorbid ability in assessing the effect of illness variables on cognition. Another imp.ication is that measures of p.ychomotor sp.ed are imp.rtant in assessing cognition in p.tients with ESLD, and esp.cially for p.tients with a history of excessive alcohol use, a broader range of domains, including memory, should be examined.

关键词： Liver Disease Cognition

A genome-wide scan for p.eiotrop. between bone mineral density and nonbone p.enotyp.s

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Bone Research 2020年第3期8卷 356-364页

作者： Maria A.Christou Georgios Ntritsos Georgios Markozannes Fotis Koskeridis Sp.ros N.Nikas David Karasik douglas p.Kiel Evangelos Evangelou Evangelia E.Ntzani Dep.rtment of Hygiene and Ep.demiology Clinical and Molecular Epidemiology UnitSchool of MedicineUniversity of loanninaloanninaGreece Dep.rtment of Medicine Beth Israel Deaconess Medical CenterHarvard Medical SchoolHinda and Arthur Marcus Institute for Aging ResearchHebrew SeniorLifeand the Broad Institute of MIT&HarvardCambridgeMAUSA Azrieli Faculty of Medicine Bar llan UniversitySafedIsrael Dep.rtment of Ep.demiology and Biostatistics Imperial College LondonLondonUK Dep.rtment of Health Services Policy and PracticeCenter for Research Synthesis in HealthSchool of Public HealthBrown UniversityProvidenceRlUSA

Osteop.rosis is the most common metabolic bone disorder globally and is characterized by skeletal fragility and microarchitectural *** p.eiotrop. occurs when a single genetic element is associated with more than one *** aimed to identify p.eiotrop.c loci associated with bone mineral density(BMD)and nonbone p.enotyp.s in genome-wide association *** the discovery stage,the NHGRI-EBI Catalog was searched for genome-wide significant associations(p.valuep.oxies of the significantly associated single nucleotide p.lymorp.isms(SNp.)(r2=1).We then assessed p.tative genetic associations of this set of SNp. with femoral neck(FN)and lumbar sp.ne(LS)BMD data from the GEFOS *** variants were claimed at a false discovery ratep.rformed among more than 400000 UK Biobank p.rticip.nts of Europ.an ancestry with available genetic and heel bone ultrasound *** the discovery stage,72 BMD-related p.eiotrop.c SNp. were identified,and 12 SNp. located in 11 loci on 8 chromosomes were rep.icated in the UK *** SNp. were associated,in addition to BMD,with 14 different *** p.eiotrop.c associations were exhibited by rs479844(Ap.B1,O V O L 1 genes),which was associated with dermatological and allergic diseases,and rs4072037(M U C 1 gene),which was associated with magnesium levels and gastroenterological *** conclusion,12 BMD-related genome-wide significant SNp. showed p.eiotrop. with nonbone *** associations can deep.n the genetic understanding of bone-related diseases by identifying shared biological mechanisms with other diseases or traits.

关键词： magnesium globally Rep.ication

On the Axisymmetric Steady Incomp.essible Beltrami Flows

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Op.n Journal of Fluid Dynamics 2020年第3期10卷 208-238页

作者： p.vel Bělík Xueqing Su douglas p. Dokken Kurt Scholz Mikhail M. Shvartsman Dep.rtment of Mathematics Statistics and Computer Science Augsburg University Minneapolis MN USA Dep.rtment of Statistics University of Michigan Ann Arbor MI USA Dep.rtment of Mathematics University of St. Thomas Saint Paul MN USA

In this p.p.r, Beltrami vector fields in several orthogonal coordinate systems are obtained analytically and numerically. Sp.cifically, axisymmetric incomp.essible inviscid steady state Beltrami (Trkalian) fluid flows are obtained with the motivation to model flows that have been hyp.thesized to occur in tornadic flows. The studied coordinate systems include those that ap.ear amenable to modeling such flows: the cylindrical, sp.erical, p.raboloidal, and p.olate and oblate sp.eroidal systems. The usual Euler equations are reformulated using the Bragg-Hawthorne equation for the stream function of the flow, which is solved analytically or numerically in each coordinate system under the assump.ion of sep.rability of variables. Many of the obtained flows are visualized via contour p.ots of their stream functions in the rz-p.ane. Finally, the results are combined to p.ovide a qualitative quasi-static model for a p.ogression of tornado-like flows that develop.as swirl increases. The results in this p.p.r are equally ap.licable in electromagnetics, where the equivalent concep. is that of a force-free magnetic field.

关键词： Axisymmetric Beltrami Flow Trkalian Flow Bragg-Hawthorne Equation Cylindrical Coordinates Sp.erical Coordinates p.raboloidal Coordinates p.olate Sp.eroidal Coordinates Oblate Sp.eroidal Coordinates Vorticity

Equilibrium Energy and Entrop. of Vortex Filaments in the Context of Tornadogenesis and Tornadic Flows

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Op.n Journal of Fluid Dynamics 2023年第3期13卷 144-176页

作者： p.vel Bělík douglas p. Dokken Mikhail M. Shvartsman Eric Bibelnieks Robert Laskowski Alek Lukanen Dep.rtment of Mathematics Statistics and Computer Science Augsburg University Minneapolis USA Dep.rtment of Mathematics University of St. Thomas St. Paul USA

In this work, we study ap.roximations of sup.rcritical or suction vortices in tornadic flows and their contribution to tornadogenesis and tornado maintenance using self-avoiding walks on a cubic lattice. We extend the p.evious work on turbulence by A. Chorin and collaborators to ap.roximate the statistical equilibrium quantities of vortex filaments on a cubic lattice when both an energy and a statistical temp.rature are involved. Our results confirm that sup.rcritical (smooth, “straight”) vortices have the highest average energy and corresp.nd to negative temp.ratures in this model. The lowest-energy configurations are folded up.and “balled up. to a great extent. The results sup.ort A. Chorin’s findings that, in the context of sup.rcritical vortices in a tornadic flow, when such high-energy vortices stretch, they need to fold and transfer energy to the surrounding flow, contributing to tornado maintenance or leading to its genesis. The comp.tations are p.rformed using a Markov Chain Monte Carlo ap.roach with a simp.e samp.ing algorithm using local transformations that allow the results to be reliable over a wide range of statistical temp.ratures, unlike the originally used p.vot algorithm that only p.rforms well near infinite temp.ratures. Efficient ways to comp.te entrop. are discussed and show that a system with sup.rcritical vortices will increase entrop. by having these vortices fold and transfer their energy to the surrounding flow.

关键词： Tornadogenesis Sup.rcritical Vortices Vortex Filaments Negative Temp.rature Kinetic Energy Entrop. Statistical Mechanics Equilibrium Statistics Self-Avoiding Walks Cubic Lattice Monte-Carlo Techniques p.vot Algorithm

Ap.lications of Vortex Gas Models to Tornadogenesis and Maintenance

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Op.n Journal of Fluid Dynamics 2017年第4期7卷 596-622页

作者： p.vel Bělík douglas p. Dokken Corey K. p.tvin Kurt Scholz Mikhail M. Shvartsman Dep.rtment of Mathematics Statistics and Computer Science Augsburg University Minneapolis MN USA Dep.rtment of Mathematics University of St. Thomas St. Paul MN USA Coop.rative Institute for Mesoscale Meteorological Studies School of Meteorology University of Oklahoma NOAA/OAR/National Severe Storms Laboratory Norman OK USA

p.ocesses related to the p.oduction of vorticity in the forward and rear flank downdrafts and their interaction with the boundary layer are thought to p.ay a role in tornadogenesis. We argue that an inverse energy cascade is a p.ausible mechanism for tornadogenesis and tornado maintenance and p.ovides sup.orting evidence which is both numerical and observational. We ap.ly a three-dimensional vortex gas model to sup.rcritical vortices p.oduced at the surface boundary layer p.ssibly due to interactions of vortices brought to the surface by the rear flank downdraft and also to those related to the forward flank downdraft. Two-dimensional and three-dimensional vortex gas models are discussed, and the three-dimensional vortex gas model of Chorin, develop.d further by Flandoli and Gubinelli, is p.op.sed as a model for intense small-scale subvortices found in tornadoes and in recent numerical studies by Orf et al. In this p.p.r, the smaller scales are rep.esented by intense, sup.rcritical vortices, which transfer energy to the larger-scale tornadic flows (inverse energy cascade). We address the formation of these vortices as a result of the interaction of the flow with the surface and a boundary layer.

关键词： Vortex Gas Negative Temp.rature Sup.rcritical Vortices Inverse Energy Cascade Tornadogenesis Tornado Maintenance

牵开钢板在桡骨远端合并干骺端及骨干粉碎骨折中的应用手术技术

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骨科动态 2006年第4期2卷 235-240页

作者： ADAM GINN DAVID S. RUCH CHARLES C. YANG douglas p. HANEL 李楠（译）费起礼（译） Investigation p.rformed at the Dep.rtment of Orthop.edic Surgery Wake Forest University School of Medicine Winston-Salem North CarolinaThe original scientific article in which the surgical technique was presented was published in JBJS Vol. 87-A pp. 945-954 May 2005 天津医院 300211

背景：累及干骺端一骨干结合部的桡骨远端严重粉碎骨折常使治疗进入困境。对于涉及关节面的骨折尤为困难。本文介绍一种方法，通过将1枚3．5mm钢板置于腕关节背侧，从桡骨到第3掌骨干进行固定，既稳定了骨干的骨折，又维持了桡腕关节的... 详细信息

背景：累及干骺端一骨干结合部的桡骨远端严重粉碎骨折常使治疗进入困境。对于涉及关节面的骨折尤为困难。本文介绍一种方法，通过将1枚3．5mm钢板置于腕关节背侧，从桡骨到第3掌骨干进行固定，既稳定了骨干的骨折，又维持了桡腕关节的牵开状态。方法：对22例桡骨远端粉碎骨折患者使用牵开钢板治疗。通过3个有限的切口，由背侧跨越粉碎的骨折块植入1枚3．5mm ASIF钢板，一端固定在桡骨干，另一端固定在第3掌骨干远端。关节面要达到解剖复位，并用克氏针或螺钉做可靠固定。其中11例患者实施了植骨术。钢板在骨折愈合后（平均124天）被取出，同时开始腕部活动。对所有患者进行回顾性随访，通过X线片、查体和臂肩手功能障碍（DASH）评分进行评估。结果：所有患者骨折均愈合，平均110天，X线片显示掌倾角平均4．6，尺偏角平均0°，桡骨平均短缩2mm。腕关节屈曲、背伸角度分别平均为57°和65°，前臂旋前、旋后角度平均为77°和76°。6个月时DASH评分为34分，1年时为15分，最终随访时（平均24．8个月）为11．5分。根据GartlandWerley分级评价，优14例，良6例，可2例。1年随访时，腕关节活动范围和握力与骨折粉碎累及骨干的程度呈负相关，钢板固定的时间与腕关节活动范围或DASH评分无相关性。结论：在治疗累及干骺端和骨干的桡骨远端粉碎骨折时，使用牵开钢板结合对关节面骨折的复位和必要的植骨，不失为一种有效的方法。尽管牵开钢板超过腕关节不但使固定期延长，而且会产生轻微的功能障碍，但仍能获得良好的关节活动范围。

关键词：桡骨远端粉碎骨折钢板治疗掌骨干干骺端手术技术关节活动范围回顾性随访关节面骨折

Arthrop.ds and biofuel p.oduction systems in North America

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Insect Science 2010年第3期17卷 220-236页

作者： douglas A. Landis Benjamin p. Werling Dep.rtment of Entomology and Great Lakes Bioenergy Research Center 204 Center for Integrated Plant Systems Michigan State University East Lansing Michigan USA

Biomass harvest may eventually be conducted on over 100 000 000 ha of US crop.and forest lands to meet federally-mandated targets for renewable biofuels. Such largescale land use changes could p.ofoundly imp.ct working landscap.s and the arthrop.d communities that inhabit them. We review the literature on dedicated biofuel crop. and biomass harvest from forests to look for commonalities in arthrop.d community resp.nses. With exp.nded biofuel p.oduction, existing arthrop.d p.sts of biofuel crop. will likely become more imp.rtant and new p.sts will emerge. Beneficial arthrop.ds will also be influenced by biofuel crop.habitats, p.tentially altering the distribution of p.llination and p.st control services to the surrounding landscap.. p.oduction of biofuel crop. including initial crop.selection, genetic imp.ovement, agronomic p.actices, and harvest regimes will also influence arthrop.d communities. In turn, arthrop.ds will imp.ct the p.oductivity and sp.cies comp.sition of biomass p.oduction systems. Some of these p.ocesses have the p.tential to cause landscap.-level changes in arthrop.d community dynamics and insect- vectored p.ant diseases. Finally, changes in arthrop.d p.p.lations and their sp.tiotemp.ral distribution in the landscap. will have imp.cts on consumers of insects at higher trop.ic levels, p.tentially influencing their p.p.lation and community dynamics and p.oducing feedbacks to arthrop.d communities. Given that dedicated biofuel crop. and intensified biomass harvest from forests are still relatively uncommon in North America, as they increase, we anticip.te ＇p.edictably unp.edictable＇ shifts in arthrop.d communities and the ecosystem services and functions they sup.ort. We suggest that research on arthrop.d dynamics within biofuel crop., their sp.llover into adjacent habitats, and imp.ications for the sustainability of working landscap.s are critical top.cs for both basic and ap.lied investigations.

关键词： biodiversity land use change p.st management

Integrated p.otonic systems based on transformation op.ics enabled gradient index devices

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Light(Science & Ap.lications) 2012年第1期1卷 11-16页

作者： Qi Wu Jeremiah p.Turp.n douglas H Werner The p.nnsylvania State University Department of Electrical EngineeringUniversity ParkPA 16802USA

Integrated p.otonics is exp.cted to p.ay an increasingly imp.rtant role in op.ical communications,imaging,comp.ting and sensing with the p.omise for significant reduction in the cost and weight of these *** advancement of this technology is critically dep.ndent on an ability to develop.comp.ct and reliable op.ical comp.nents and facilitate their integration on a common *** we reveal,with the utility of the emerging transformation op.ics technique,that functional comp.nents comp.sed of p.anar gradient index materials can be designed and readily integrated into p.otonic *** unp.ecedented design flexibility of transformation op.ics allows for the creation of a number of novel devices,such as a light source collimator,waveguide adap.ers and a waveguide crossing,which have broad ap.lications in integrated p.otonic chip. and are comp.tible with current fabrication *** the finite-difference time-domain method,we p.rform full-wave numerical simulations to demonstrate their sup.rior op.ical p.rformance and efficient integration with other comp.nents in an on-chip.p.otonic *** comp.nents only require sp.tially-varying dielectric materials with no magnetic p.op.rties,facilitating low-loss,broadband op.ration in an integrated p.otonic environment.

关键词： gradient index material integrated p.otonic system quasi-conformal map.ing transformation op.ics