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c.c.ic.performanc. and simplified pushover analyses of prec.st segmental c.nc.ete bridge c.lumns with c.rc.lar sec.ion

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 297-312页

作者： Bu Zhanyu Guo Jian Zheng Rongyue Song Jianwei george c.Lee Fac.lty of Arc.itec.ural Civil Engineering and Environment Ningbo University c.llege of c.vil Engineering and Arc.itec.ure Zhejiang University of Technology Department of c.vil Structural and Environmental Engineering University at Buffalo

In rec.nt years, prec.st segmental c.nc.ete bridge c.lumns bec.me prevalent bec.use of the benefits of ac.elerated c.nstruc.ion, low environmental impac., high quality and low life c.c.e c.sts. The lac. of a detailed c.nfiguration and appropriate design proc.dure to ensure a c.mparable performanc. with monolithic.c.nstruc.ion has impeded this struc.ural system from being widely used in areas of high seismic.ty. In this study, prec.st segmental bridge c.lumn c.c.ic.loading tests were c.nduc.ed to investigate the performanc. of unbonded post-tensioned segmental bridge c.lumns. One monolithic.and two prec.st segmental c.lumns were tested. The preeast segmental c.lumn exhibited minor damage and small residual displac.ment after the maximum 7% c.c.ic.drift; energy dissipation （ED） c.n be enhanc.d byadding ED bars. The experimental results were modeled by a simplified pushover method （SPOM）, as well as a fiber model （FIBM） finite element method. Forty-five c.ses of c.lumns with different aspec. ratios, axial load ratios and ED bar ratios were analyzed with the SPOM and FIBM, respec.ively. Using these parametric.results, a simplified design method was suggested by regressive analysis. Satisfac.ory c.rrelation was found between the experimental results and the simplified design method for preeast segmental c.lumns with different design parameters.

关键词： prec.st c.nc.ete segmental c.lumn simplified pushover fiber model

Virtual endosc.py of the urinary trac.

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Asian Journal of Andrology 2006年第1期8卷 31-38页

作者： george c.Kagadis Dimitrios Siablis Evangelos N.Liatsikos Theodore Petsas george c. Nikiforidis Department of Medic.l Physic. Department of Radiology Department of Urology School of MedicineUniversity of PatrasGR 26500 RionGreece Department of Radiology Department of Medic.l Physic.

Tec.nologic.l breakthroughs have advanc.d the temporal and spatial resolutions of diagnostic.imaging, and 3 dimensional （3-D） rec.nstruc.ion tec.niques have been introduc.d into everyday c.inic.l prac.ic.. Virtual endosc.py （VE） is a non-invasive tec.nique that amplifies the perc.ption of c.oss-sec.ional images in the 3-D spac., providing prec.se spatial relationships of pathologic.l regions and their surrounding struc.ures. A variety of c.mputer algorithms c.n be used to generate 3-D images, taking advantage of the information inherent in either spiral c.mputed tomography or magnetic.resonanc. imaging （MRI）. VE images enable endoluminal navigation through hollow organs, thus simulating c.nventional endosc.py. Several c.inic.l studies have validated the diagnostic.utility of virtual c.stosc.py, whic. has high sensitivity and spec.fic.ty rates in the detec.ion of bladder tumor. Published experienc. in the virtual exploration of the renal pelvis, ureter and urethra is enc.uraging but still sc.rc.. VE is a safe, non-invasive method that c.uld be applied in the long-term follow-up of patients with ureteropelvic.junc.ion obstruc.ion, urinary bladder tumors and ureteral and/or urethral stric.ures. Its princ.pal limitations are the inability to provide biopsy tissue spec.mens for histopathologic.examination and the assoc.ated ionizing radiation hazards （unless MR/is used）. However, in the c.se of endoluminal stenosis or obstruc.ion, VE permits virtual endoluminal navigation both c.phalad and c.udal to the stenotic.segment. To c.nc.ude, VE provides a less invasive method of evaluating the urinary trac., espec.ally for c.inic.ans who are less familiar with c.oss-sec.ional imaging than radiologists. （Asian J Androl 2006 Jan; 8： 31-38）

关键词： c.mputed tomography three-dimensional imaging virtual endosc.py urethral stric.ure

Mac.ine perfusion of the liver: Whic. is the best tec.nique to mitigate isc.aemia-reperfusion injury?

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World Journal of Transplantation 2019年第1期9卷 14-20页

作者： Yuri L Boteon simon c.Afford Liver Unit Queen Elizabeth HospitalUniversity Hospitals Birmingham NHS Foundation Trust c.ntre for Liver and Gastrointestinal Researc. Institute of Immunology and ImmunotherapyCollege of Medical and Dental SciencesUniversity of Birmingham National Institute for Health Researc. (NIHR) Birmingham Biomedic.l Researc. c.ntre University of Birmingham and University Hospitals Birmingham NHS Foundation Trust

Longstanding researc. desc.ibes the mec.anisms whereby the restoration of blood flow and reoxygenation(reperfusion) aggravates the isc.aemic.injury c.used by a period of anoxia to a donor liver. This phenomenon, c.lled isc.aemia-reperfusion injury(IRI), leads to parenc.ymal c.ll death,mic.oc.rc.latory failure, and inflammatory immune response. c.inic.lly, IRI is the main fac.or responsible for the oc.urrenc. of posttransplant graft dysfunc.ion and isc.aemic.type biliary lesions. While extended c.iteria donor livers are more vulnerable to IRI, their utilisation is required to address the shortfall in donor organs. Thus, the mitigation of IRI should drive the setting of a new benc.mark for marginal organ preservation. Herein, strategies inc.rporating different modalities of mac.ine perfusion of the liver to alleviate IRI are disc.ssed in c.njunc.ion with advantages and disadvantages of individual *** leading to reperfusion of the liver during mac.ine perfusion(in situ normothermic.regional perfusion and ex situ normothermic.mac.ine perfusion)may mitigate IRI by shortening the isc.aemic.period of the organs. This benefit potentially esc.lates from the minimum level, obtained following just partial alleviation of the isc.aemic.period, to the maximum level, whic. c.n be potentially ac.ieved with isc.aemia-free organ transplantation. Tec.niques that do not lead to reperfusion of the liver during mac.ine perfusion(hypothermic.subnormothermic. and c.ntrolled-oxygenated rewarming) optimise mitoc.ondrial oxidative func.ion and replenish c.llular energy stores, thereby lowering reac.ive oxygen spec.es produc.ion as well as the ac.ivation ofdownstream inflammatory pathways during reperfusion. Further mec.anistic.insights into IRI may guide the development of donor-spec.fic.protoc.ls of mac.ine perfusion on the basis of the limitations of individual c.tegories of extended c.iteria donor organs.

关键词： Mac.ine perfusion of the liver Isc.aemia-reperfusion injury Liver transplantation Organ preservation Organ rec.nditioning

Effec. of different surfac. treatments on bioac.ivity of porous titanium implants

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Journal of Materials Sc.enc. & Tec.nology 2019年第3期35卷 418-426页

作者： M.Todea A.Vulpoi c.Popa P.Berc. S.simon Institute of Interdisc.plinary Researc. in Bio-Nano-Sc.enc.s Babes Bolyai University Department of Molec.lar Sc.enc.s Faculty of Medicine Iuliu Hatieganu University of Medicine and Pharmacy Tec.nic.l University of c.uj-Napoc. Faculty of Materials Science and Engineering Department of Materials Science and Technology Tec.nic.l University of c.uj-Napoc. Faculty of Machine Building & National Centre of Rapid Prototyping

The work aims to c.arac.erize the struc.ure and to evaluate in vitro the effec. of different surfac. treatments on the bioac.ivity of medic.l grade Ti6Al7 Nb alloy implants manufac.ured by selec.ive laser melting. In order to improve the bioac.ivity of these samples, they were subjec.ed to heat treatment,c.emic.l treatment, and impregnation with bioac.ive materials. To evaluate the apatite forming ability, the samples were immersed in simulated body fluid solution) and c.arac.erized before and after immersion by sc.nning elec.ron mic.osc.py, X-ray diffrac.ion and X-ray photoelec.ron *** c.mposition and the texture of the surfac.s after the applied treatments have a selec.ive effec. on apatite layer development on the surfac. of samples.

关键词： Ti6Al7Nb alloy Laser proc.ssing c.mposite materials Surfac. properties Bioac.ivity

Subspec.fic.variation in sperm morphology and performanc. in the Long-tailed Finc. (Poephila ac.tic.uda)

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c.inese Birds 2015年第4期6卷 225-234页

作者： Melissah Rowe simon c.Griffith Antje Hofgaard Jan T.Lifjeld Natural History Museum University of Oslo c.ntre for Ec.logic.l and Evolutionary Synthesis Department of BiosciencesUniversity of Oslo Department of Biologic.l Sc.enc.s Macquarie University Elec.ron Mic.osc.pic.l Unit for Biologic.l Sc.enc.s Department of BiosciencesUniversity of Oslo

Bac.ground: Evolutionary biology endeavours to explain biologic.l diversity,and as suc. it is c.itic.l to develop an understanding of the adaptive and func.ional signific.nc. of trait *** exhibit remarkable levels of morphologic.l ***,our understanding of the evolutionary c.uses and func.ional signific.nc. of this variation is limited,espec.ally at the intraspec.fic.***: We quantified variation in sperm morphology and performanc. between two subspec.es of Long-tailed Finc.(Poephila ac.tic.uda ac.tic.uda and ***),a small grassfinc. found in tropic.l northern *** a zone of sec.ndary c.ntac.,these subspec.es are maintained as two distinc. forms: *** oc.urs in the western part of the spec.es' range and has a yellow bill,while *** exhibits a red bill and is found in the eastern part of the ***: We found small,but signific.nt differenc.s in sperm size between these subspec.es(*** had longer and narrower sperm than ***),whic. was surprising given the rec.nt evolutionary origins of these two taxa(i.e.0.3 million years ago).Additionally,both subspec.es exhibited high values of between- and within-male variation in sperm morphology,though in the c.se of sperm midpiec. length this variation was signific.ntly lower in *** relative to ***: We suggest these observed differenc.s in sperm morphology are the result of genetic.drift and reflec. historic.l proc.sses assoc.ated with divergenc. between the eastern and western populations of these two ***,we disc.ss the potential implic.tions of our findings for the proc.ss of population divergenc. and reproduc.ive isolation.

关键词： Passerine Reproduc.ive barriers Sperm evolution Struc.ure-func.ion relationships

东营凹陷沙河街组泥页岩中正丙基胆甾烷与异海绵烷的研究:硫循环对有机质富集的影响

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南京大学学报（自然科学版） 2020年第3期56卷 366-381页

作者：许汇源侯读杰 simon c.george 刘全有页岩油气富集机理与有效开发国家重点实验室北京100083 中国石油化工股份有限公司石油勘探开发研究院北京100083 中国地质大学(北京) 能源学院北京100083 Department of Earth and Environmental Sc.enc.s Macquarie UniversitySydney 2109Australia

中国东部陆相渤海湾盆地东营凹陷古近系沙河街组油页岩中有机质的富集机制一直是研究热点,但关于异养生物及硫循环对有机质富集过程影响的研究较少.通过有机地球化方法对东营凹陷沙河街组第三、四段富有机质烃源岩进行精细研究,认为伴... 详细信息

中国东部陆相渤海湾盆地东营凹陷古近系沙河街组油页岩中有机质的富集机制一直是研究热点,但关于异养生物及硫循环对有机质富集过程影响的研究较少.通过有机地球化方法对东营凹陷沙河街组第三、四段富有机质烃源岩进行精细研究,认为伴随着明显的水体分层,藻类勃发进一步加剧了底水缺氧的条件,海水带来了丰富的硫酸盐促进了强烈的细菌硫还原(Bac.erial Sulfur Reduc.ion,BSR)作用,将这种缺氧条件进一步扩展到水柱上部形成透光层缺氧(Photic.Zone Euxinia,PZE),而PZE有利于光合自养绿硫菌的剧烈活动.强烈的BSR作用及间歇性的PZE控制东营凹陷古湖盆中藻类等水生生物的组成,原核细菌及海相金藻类对有机质富集有一定贡献.通过分析海相藻类生物标志物c.024-正丙基胆甾烷和透光层缺氧生物标志物异海绵烷与有机碳丰度的关系,研究认为在相对丰富的外源硫酸盐输入、厌氧异养细菌作用、光能自养细菌作用和透光层缺氧条件下形成的硫循环,对东营古湖盆沙河街组烃源岩有机质的富集起主要控制作用.

关键词：渤海湾盆地东营凹陷正丙基胆甾烷异海绵烷透光层缺氧海侵硫循环

The multi-kingdom mic.obiome c.talog of the c.ic.en gastrointestinal trac.

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Biosafety and Health 2024年第2期6卷 101-115页

作者： Yanan Wang Mengqi Qu Yuhai Bi William J.Liu Sufang Ma Bo Wan Yongfei Hu Baoli Zhu Gaiping Zhang george F.Gao International Joint Researc. c.nter of National Animal Immunology College of Veterinary MedicineHenan Agricultural UniversityZhengzhou 450046China c.S Key Laboratory of Pathogen Mic.obiology and Immunology Institute of MicrobiologyChinese Academy of Sciences(CAS)Beijing 100101China Longhu Laboratory Zhengzhou 450046China University of c.inese Ac.demy of Sc.enc.s Beijing 100049China NHc.Key Laboratory of Biosafety National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China State Key Laboratory of Animal Nutrition and Feeding College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

c.ic.en is an important food animal worldwide and plays an important role in human life by providing meat and *** rec.nt signific.nt advanc.s in gut mic.obiome studies,a c.mprehensive study of c.ic.en gut bac.erial,arc.aeal,and viral genomes remains *** this study,we c.nstruc.ed a c.ic.en multi-kingdom mic.obiome c.talog(c.KMc.,inc.uding 18,201 bac.erial,225 arc.aeal,and 33,411 viral genomes,and annotated over 6,076,006 protein-c.ding genes by integrating 135 c.ic.en gut metagenomes and public.y available metagenome-assembled genomes(MAGs)from ten *** found that 812 and 240 MAGs in our dataset were putative novel spec.es and genera,respec.ively,far beyond what was previously *** newly unc.assified MAGs were predominant in Phyla Firmic.tes_A(n=263),followed by Firmic.tes(n=126),Bac.eroidota(n=121),and Proteobac.eria(n=87).Most of the c.assified spec.es-level viral oper-ational taxonomic.units belong to ***,63.24%of c.ic.en gut viromes are predic.ed to infec. two or more hosts,inc.uding c.mplete c.rc.lar ***,we found that diverse auxiliary metabolic.genes and antibiotic.resistanc. genes were c.rried by ***,our c.KMc.provides the largest integrated MAGs and viral genomes from the c.ic.en gut to date,func.ional insights into the c.ic.en gastrointestinal trac. mic.obiota,and paves the way for mic.obial interventions for better c.ic.en health and produc.ivity.

关键词： c.ic.en Mic.obiome Metagenome assembled genomes Arc.aeome Virome Antibiotic.resistanc. gene

OPTIMIZATION OF A WAVE c.Nc.LLATION MULTIHULL SHIP USING c.D TOOLS

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Journal of Hydrodynamic. 2002年第1期14卷 1-7页

作者： c. Yang, R. L■hner, O. Soto (Sc.ool of c.mputational Sc.enc.s, george Mason University Fairfax VA 22030-4444, USA) Sc.. of c.mp. Sc.. George Mason Univ. Fairfax VA 22030-4444 United States

A simple c.D tool, c.upled to a disc.ete surfac. representation and a gradient based optimization proc.dure, is applied to the design of optimal hull forms and optimal arrangement of hulls for a wave c.nc.llation multihull ship. The c.D tool, whic. is used to estimate the wave drag, is based on the zeroth order slender ship approximation. The hu ll surfac. is represented by a triangulation, and almost every grid point on the surfac. c.n be used as a design variable. A smooth surfac. is obtained via a si mplified pseudo shell problem. The optimal design proc.ss c.nsists of two steps . The optimal c.nter and outer hull forms are determined independently in the fi rst step, where eac. hull forms are determined independently in the first step, where eac. hull keeps the same displac.ment as the original design while the wav e drag is minimized. The optimal outer hull arrangement is determined in the se c.nd step for the optimal c.nter and outer hull forms obtained in the first step . Results indic.te that the new design c.n ac.ieve a large wave drag reduc.ion i n c.mparison to the original design c.nfiguration.

关键词： hull form design hull form optimiza tion wave c.nc.llation multihull ship trimaran wave resistanc. c.D tools sl ender ship approximation surfac. parameterization.

Near-fault ground motions with prominent ac.eleration pulses:pulse c.arac.eristic. and duc.ility demand

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Earthquake Engineering and Engineering Vibration 2007年第3期6卷 215-223页

作者： Mai Tong Vladimir Rzhevskyt Dai Junwu george c.Lee Qi Jinc.eng Qi Xiaozhai Mc.ER State University of New York at Buffalo USA Institute of Enginering Mec.anic. China Earthquake Administration Harbin 150080 China

Major earthquakes of last 15 years （e.g., Northridge 1994, Kobe 1995 and c.i-c.i 1999） have shown that many near-fault ground motions possess prominent ac.eleration pulses. Some of the prominent ground ac.eleration pulses are related to large ground veloc.ty pulses, others are c.used by mec.anisms that are totally different from those c.using the veloc.ty pulses or fling steps. Various efforts to model ac.eleration pulses have been reported in the literature. In this paper, researc. results from a rec.nt study of ac.eleration pulse prominent ground motions and an analysis of struc.ural damage induc.d by ac.eleration pulses are summarized. The main results of the study inc.ude：（1） temporal c.arac.eristic. of ac.eleration pulses; （2） duc.ility demand spec.rum of simple ac.eleration pulses with respec. to equivalent c.asses of dynamic.systems and pulse c.arac.eristic.parameters; and （3） estimation of fundamental period c.ange under the exc.tation of strong ac.eleration pulses. By using the ac.eleration pulse induc.d linear ac.eleration spec.rum and the duc.ility demand spec.rum, a simple proc.dure has been developed to estimate the duc.ility demand and the fundamental period c.ange of a reinforc.d c.nc.ete （Rc. struc.ure under the impac. of a strong ac.eleration pulse.

关键词： near-fault ground motions ac.eleration pulse duc.ility demand spec.rum