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Phylogenetic reconstruction of.Chirita and allies (Gesneriaceae) with taxonomic treatments

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Journal of.Systematics and Evolution 2011年第1期49卷 50-64页

作者： james f. SMITH Department of.Biological Sciences Boise State University

Chirita D. Don, a large genus in the subf.mily Cyrtandroideae of.Gesneriaceae, has been the subject of.much debate whether it is a natural group or not. In addition, the highly heterogeneous Chirita has also been very problematic with regard to delimitation and subdivision. Here we used the nrDNA internal transcribed spacer and cpDNA trnL-f.f.r molecular phylogenetic analaysis, combined with morphological data. Our results suggest that Chirita is an artif.cial, polyphyletic genus. The most important character that def.nes Chirita, the dorso-ventrally oblique and bilamellar stigma, has evolved convergently in dif.erent clades of.diandrous Cyrtandroideae. Chirita sensu stricto only includes the species of.Chirita sect. Chirita, whereas Chirita sect. Microchirita is an independent clade located at the basal node of.the phylogenetic tree. Chirita sect. Liebigia is closely related to Didymocarpus with an entire stigma unlike other species of.Chirita. The species of.Chirita sect. Gibbosaccus, Chiritopsis, Primulina, and Wentsaiboea f.rm a monophyletic group that is sister to a strongly supported clade comprising f.ur monotypic genera Paralagarosolen, Calcareoboea, Petrocodon, and Tengia. We f.rther analyzed the morphological evolution of.Chirita and identif.ed a series of.morphological synapomorphies f.r the monophyletic groups revealed herein, and thereby provide a taxonomic treatment in this study.

关键词： Chirita D. Don morphological evolution phylogenetic reconstruction polyphyly taxonomic treatment.

The song remains the same： Juvenile Richardson＇s ground squirrels do not respond dif.erentially to mother＇s or colony member＇s alarm calls

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Current Zoology 2012年第5期58卷 773-780页

作者： james f. HARE Kurtis J. WARKENTIN Department of.Biological Sciences University of Manitoba Winnipeg MB Canada R3T 2N2 Department of.Zoology Brandon University Brandon MB R7A 6A9

Alarm calls are emitted by Richardson＇s ground squirrels Urocitellus richardsonii in response to avian and terrestrial predators. Conspecif.cs detecting these calls respond with increased vigilance, promoting predator detection and evasion, but in doing so, lose time f.om f.raging. That loss can be minimized if.alarm call recipients discriminate among signalers, and weight their response accordingly. f.r juvenile ground squirrels, we predicted that the trade-of. between f.raging and vigilance could be optimized via selective response to alarm calls emitted by their own dam, and/or neighboring colony members over calls broad- cast by less f.miliar conspecif.cs. Alarm calls of.adult f.male Richardson＇s ground squirrels were elicited in the f.eld using a predator model and recorded on digital audio tape. f.ee-living f.cal juveniles were subjected to playbacks of.a call of.their mother, and on a separate occasion a call f.om either another adult f.male f.om their own colony, or an adult f.male f.om another colony. Neither immediate postural responses and escape behavior, nor the duration of.vigilance manif.sted by juveniles dif.ered with exposure to alarm calls of.the three adult f.male signaler types. Thus, juveniles did not respond pref.rentially to alarm calls emitted by their mothers or colony members, likely ref.ecting the high cost of.ignoring alarm signals where receivers have had limited opportunity to establish past signaler reliability [Current Zoology 58 （5）： 773-780, 2012].

关键词： Alarm Signal Communication Maternal Call Recognition Signal Reliability Ground Squirrel Social Discrimination

Design of.Poiseuille f.ow Controllers Using the Method of.Inequalities

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International Journal of.Automation and computing 2009年第1期6卷 14-21页

作者： John McKernan james f. Whidborne George Papadakis Department of.Mechanical Engineering King s College London Strand Department of.Aerospace Sciences Cranfield University

This paper investigates the use of.the method of.inequalities （MoI） to design output-f.edback compensators f.r the problem of.the control of.instabilities in a laminar plane Poiseuille f.ow. In common with many f.ows, the dynamics of.streamwise vortices in plane Poiseuille f.ow are very non-normal. Consequently, small perturbations grow rapidly with a large transient that may trigger nonlinearities and lead to turbulence even though such perturbations would, in a linear f.ow model, eventually decay. Such a system can be described as a conditionally linear system. The sensitivity is measured using the maximum transient energy growth, which is widely used in the f.uid dynamics community. The paper considers two approaches. In the f.rst approach, the MoI is used to design low-order proportional and proportional-integral （PI） controllers. In the second one, the MoI is combined with Mcf.rlane and Glover＇s H∞ loop-shaping design procedure in a mixed-optimization approach.

关键词： Transient energy growth transient behaviour f.ow control Poiseuille f.ow method of.inequalities (MoI) mixed opti-mization H∞-optimization.

Intermediate accounting J. David Spiceland, james f. Sepe, Lawrence A. Tomassini 3rd ed.

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Guided Explorations of.the Mechanics of.Solids and Structures (Cambridge Aerospace Series)

2004年

作者： J. David Spiceland james f. Sepe Lawrence A. Tomassini

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Characteristics of.Rat Lumbar Vertebral Body Bone Mineral Density and Dif.erential Segmental Responses to Sex Hormone Def.ciency:a Clinical Multidetector Computed Tomography Study

1000年

作者： james f. Doyle

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Biomedical and Environmental Sciences 2012年第6期25卷 607-613页

作者： DENG Min WANG Yi Xiang james f. GRIf.ITH LU Gang Anil T AHUJA POON Wai S Department of.Imaging and Interventional Radiology Prince of Wales Hospital the Chinese University of Hong Kong Shatin N.T. Hong Kong China Division of.Neurosurgery Department of Surgery Prince of Wales Hospital the Chinese University of Hong Kong Shatin N.T. Hong Kong China

Objective To investigate sex hormone def.ciency related osteoporosis and ef.icacy of.dif.erent therapies. Methods Orchiectomized and ovariectomized rat models are used to investigate sex hormone def.ciency related osteoporosis and ef.icacy of.dif.erent therapies. A rat vertebral body can be longitudinally divided into central portion, which contain more trabecular bone, and para-endplate portions which contain more compact bone. In matured male and f.male Wistar and Sprague-Dawley rat lumbar spines, we investigated baseline bone mineral density （BMD） characteristics and the dif.erential segmental responses in bone loss within the lumbar vertebral body post gonadal surgery with clinical multidetector computed tomography. Results Para-endplate sections had a higher BMD than central sections. The cephalad para-endplate sections had a higher BMD than the caudad para-endplate sections. Eight weeks af.er gonadal removal, there was more bone loss in central sections than para-endplate sections. The relative dif.erence of.bone loss between para-endplate and central sections was more apparent in male rats than in f.male rats. There was more bone loss in caudad sections than cephalad sections; this lead to a f.rther increase of.BMD dif.erence between caudad para-endplate sections and cephalad para-endplate sections post gonadal surgery. Conclusion The approach described in this study provided a consistent way to study BMD change within predominantly compact bone portion and trabecular bone portion of.the vertebral body.

关键词： Bone mineral density Quantitative computed tomography, Rat Vertebra Orchiectomy Ovariectomy Cortical bone Trabecular bone

Counting and Randomly Generating <i>k</i>-Ary Trees

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Applied Mathematics 2021年第12期12卷 1210-1215页

作者： james f. Korsh Computer and Inf.rmation Science Department Temple University Philadelphia USA

k-ary trees are one of.the most basic data structures in Computer Science. A new method is presented to determine how many there are with n nodes. This method gives additional insight into their structure and provides... 详细信息

关键词： Combinatorial Problems k-Ary Trees Random Generation

Interaction f.rces between sof. magnetic particles in unif.rm and non-unif.rm magnetic f.elds

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Acta Mechanica Sinica 2010年第6期26卷 921-929页

作者： Ayyoub Mehdizadeh james f.Klausner Nima Rahmatian Department of.Mechanical and Aerospace Engineering University of FloridaP.O.Box 116300GainesvilleFL 32611-6300USA

The inf.uence of.the magnetization of.a sof. magnetic sphere on the surrounding magnetic f.eld is measured and *** interaction f.rce between two sof. magnetic particles is directly measured using an ultra precision load sensor in unif.rm and non-unif.rm magnetic f.elds. The interaction f.rce largely f.llows an inverse f.urth power law as a f.nction of.separation distance between particle centers. At small distances,the ef.ect of.magnetization of.one particle on the magnetization of.its adjacent particle causes the attractive（repulsive） f.rce to be larger（smaller） than that predicted by the inverse f.urth power *** theoretical prediction based on a modif.ed dipole model,that takes into account the coupling ef.ect of.the magnetization among sof. magnetic particles,gives excellent agreement with the measured f.rce in a unif.rm magnetic *** interaction f.rce under a non-unif.rm applied magnetic f.eld can be reasonably predicted using the dipole-dipole interaction model when the local magnetic f.eld is used to determine the magnetization.

关键词： Magnetic f.rce Magnetic charge model Magnetic dipole model Sof. magnetic particle

An international physical activity and public health research agenda to inf.rm coronavirus disease-2019 policies and practices

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Journal of.Sport and Health Science 2020年第4期9卷 328-334页

作者： james f.Sallis Deepti Adlakha Adewale Oyeyemi Deborah Salvo Department of.f.mily and Preventive Medicine University of California San DiegoLa JollaCA 92093USA Mary Mackillop Institute f.r Health Research Australian Catholic UniversityMelbourne 3000Australia School of.Natural and Built Environment Queen’s University BelfastBelfast BT95AGUK Department of.Physiotherapy College of Medical SciencesUniversity of MaiduguriMaiduguri 600243Nigeria Prevention Research Center Brown SchoolWashington University in St.LouisSt.LouisMO 63130USA

Physical activity(PA)has strong relevance f.r limiting the harms to human health and well-being due to the coronavirus disease-2019(COVID-19)pandemic.1 Active muscles produce chemicals that improve immune f.nctioning,which in turn reduces the extent of.inf.ctions,and decreases inf.ammation,and these are the main causes of.the lung damage f.om severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** is a powerf.l preventive and therapeutic intervention f.r the most common pre-existing chronic conditions that increase risk of.severe COVID-19 inf.ctions and mortality.

关键词： inf.ammation mortality lung