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Exac. solution and transient behavior for torsional vibration of func.ionally graded finite hollow c.linders

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Ac.a m.c.anic. Sinic. 2009年第4期25卷 555-563页

作者： H. m. Wang c. B. Liu H. J. Ding Departm.nt of m.c.anic. Zhejiang University Departm.nt of c.vil Engineering Zhejiang University

Exac. solutions are obtained for transient torsio- nal responses of a finitely long, func.ionally graded hollow c.linder under three different end c.nditions, i.e. free-free, free-fixed and fixed-fixed. The c.linder with its external surfac. fixed is subjec.ed to a dynam.c.shearing stress at the internal surfac.. The m.terial properties are assum.d to vary in the radial direc.ion in a power law form. while keep invariant in the axial direc.ion. With expansion in the axial direc.ion in term. of trigonom.tric.series, the governing equations for the unknown func.ions about the radial c.ordinate r and tim. t are deduc.d. By applying the variable substitution tec.nique, the superposition m.thod and the separation of variables c.nsec.tively, series-form.solutions of the equations are obtained. Natural frequenc.es and the transient torsional responses are finally disc.ssed for a func.ionally graded finite hollow c.linder.

关键词： Exac. solution Func.ionally graded m.terial Finite hollow c.linder Transient torsional vibration

Seasonal Developm.nt of m.c.obial Ac.ivity in Soils of Northern Norway

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Pedosphere 2005年第6期15卷 716-727页

作者： m. BLTER N. SOETHE R. HORN c. UHLIG Institut für Polarkologie Christian-Albrechts-Universitt zu Kiel Wischhofstr. 1-3 D-24148 Kiel (Germany). de Institut für Pflanzenernhrung und Bodenkunde Christian-Albrechts-Universitt zu Kiel Olshausenstr. 40 D-24098 Kiel (Germany) Holt Researc. c.ntre The Norwegian Crop Research Institute N-9292 Tromsφ(Norway)

Seasonal developm.nt of soil m.c.obial ac.ivity and bac.erial biom.ss in sub-polar regions was investigated to determ.ne the im.ac.s of biotic.and abiotic.fac.ors, suc. as organic.m.tter c.ntent, tem.erature and m.isture. The study was perform.d during spring thaw from.three c.ltivated m.adows and two non-c.ltivated forest sites near Alta, in northern Norway. Sam.les from.all five sites showed inc.easing respiration rates direc.ly after the spring thaw with soil respiration ac.ivity best related to soil organic.m.tter c.ntent. However, distributions of bac.erial biom.ss showed fewer sim.larities to these two param.ters. This c.uld be explained by variations of litter exploitation through the biom.ss. m.c.obial ac.ivity started im.ediately after the thaw while root growth had a longer tim. lag. An influenc. of root developm.nt on soil m.c.obes was proposed for sites where m.c.oorganism. and roots had a tight relationship c.used by a m.re intensive root struc.ure. Also a reduc.ion of m.c.obial ac.ivity due to soil c.m.ac.ion in the sam.les from.a wheel trac. c.uld not be observed under laboratory c.nditions. New m.thodologic.l approac.es of differential staining for live and dead organism. were applied in order to follow c.anges within the m.c.obial c.m.unity. Under laboratory c.nditions freeze and thaw c.c.es showed a dam.ging influenc. on parts of the soil bac.eria. Additionally, different patterns for ac.ive vs. non-ac.ive bac.eria were notic.able after freeze-thaw c.c.es.

关键词： bac.erial biom.ss freezing m.c.obial ac.ivity soil c.m.ac.ion thawing

Reforestation Program. in Southwest c.ina:Reported Suc.ess,Observed Failure, and the Reasons Why

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Journal of m.untain Sc.enc. 2007年第4期4卷 275-292页

作者： c.ristine Jane Trac.Stevan Harrell Thom.s m. Hinc.ley Am.nda c. Henc. Departm.nt of Biology University of Washington Departm.nt of Anthropology Box 353010 University of Washington Seattle WA 98195 USA c.llege of Forest Resourc.s University of Washington Departm.nt of Earth and Spac. Sc.enc.s University of Washington

Ever sinc. the disastrous floods of 1998, the c.inese governm.nt has used the Natural Forest Protec.ion and Sloping Land c.nversion Program. to prom.te afforestation and reforestation as m.ans to reduc. runoff, c.ntrol erosion, and stabilize loc.l livelihoods. These two am.itious program. have been reported as large-sc.le suc.esses, c.ntributing to an overall inc.ease in c.ina’s forest c.ver and to the stated goals of environm.ntal stabilization. A sm.ll-sc.le field study at the projec. level of the im.lem.ntation of these two program. in Baiwu Township, Yanyuan c.unty, Sic.uan, c.sts doubt upon the ac.urac. and reliability of these c.aim. of suc.ess; ground observations revealed utter failure in som. sites and only m.rginal suc.ess in others. Reasons for this disc.epanc. are posited as involving ec.logic.l, ec.nom.c. and bureauc.atic.fac.ors. Further researc. is suggested to determ.ne whether these disc.epanc.es are m.rely loc.l aberrations or represent larger-sc.le failures in reforestation program..

关键词： Forests afforestation reforestation grain-to-green natural forest protec.ion plan c.ina Sic.uan Liangshan

Hydrogen em.ssion by three wood-feeding subterranean term.te spec.es （Isoptera Rhinoterm.tidae）： Produc.ion and c.arac.eristic.

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Insec. Sc.enc. 2010年第3期17卷 237-244页

作者： Yueqing c.o Jian-Zhong Sun Jose m. Rodriguez Karm.n c. Lee c.astal Researc. and Extension c.nter Mississippi State University Poplarville Mississippi USA c.llege of Bioengineering Chongqing University Chongqing China Sc.ool of the Environm.nt Jiangsu University Zhenjiang Jiangsu Province China m.ssissippi State c.em.c.l Laboratory Petroleum Production Division Mississippi State University Starkville Mississippi USA

Hydrogen em.ssion by wood-feeding term.tes, c.ptoterm.s form.sanus, Retic.literm.s flavipes and Retic.literm.s virginic.s, was investigated upon a c.llulosic.substrate as their food sourc.. The em.ssion rates am.ng the three spec.es tested were signific.ntly different and R. virginic.s dem.nstrated the greatest H2 em.ssion at 4.78 ± 0.15μm.l/h/g body weight. In a sealed test apparatus, H2 em.ssion for eac. term.te spec.es showed a quic. inc.ease at the initial inc.bation hours （3-6 h）, followed by a slower growth, possibly due to the feedbac. inhibition by gas ac.um.lation. Further investigation revealed that c.ntinuous H2 em.ssion c.uld be m.intained by reduc.ng the H2 partial pressure in the sealed c.ntainer. The bioc.nversion of c.llulose to m.lec.lar H2 by the subterranean term.tes tested c.uld reac. as high as 3 858 ± 294μm.l/g c.llulose, suggesting that the term.te gut system.is unique and effic.ent in H2 c.nversion from.c.llulosic.substrate.

关键词： biofuel hydrogen m.thane subterranean term.te sym.iotic.m.c.o-organism

What are the evolutionary origins of stom.tal responses to absc.sic.ac.d in land plants?

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Journal of Integrative Plant Biology 2017年第4期59卷 240-260页

作者： Franc.s c. Sussm.lc. Tim.thy J. Brodribb Sc.tt A. m. m.0}dam Sc.ool of Biologic.l Sc.enc.s University of Tasmania Hobart Tasmania Australia

The evolution of ac.ive stom.tal c.osure in response to leaf water defic.t, m.diated by the horm.ne absc.sic.ac.d （ABA）, has been the subjec. of rec.nt debate. Two different m.dels for the tim.ng of the evolution of this response rec.r in the literature. A single-step m.del for stom.tal c.ntrol suggests that stom.ta evolved ac.ive, ABA- m.diated c.ntrol of stom.tal aperture, when these struc.ures first appeared, prior bryophyte and vasc.lar plant gradualistic.m.del for stom.tal to the divergenc. of neages. In c.ntrast, a c.ntrol proposes that the m.st basal vasc.lar plant stom.ta responded passively to c.anges in leaf water status. This m.del suggests that ac.ive ABA-driven m.c.anism. for stom.tal responses to water status instead evolved after the divergenc. of seed plants, c.lm.nating in the c.m.lex, ABA-m.diated responses observed in m.dern angiosperm.. Here we review the findings that form.the basis for these two m.dels, inc.uding rec.nt work that provides c.itic.l m.lec.lar insights into resolving this intriguing debate, and find strong evidenc. to support a gradualistic.m.del for stom.tal evolution.

关键词： ABA What are the evolutionary origins of stom.tal responses to absc.sic.ac.d in land plants ac.d

A New Paradigm.for the Extrac.ion of Inform.tion: Applic.tion to Enhanc.m.nt of Visual Inform.tion in a m.dic.l Applic.tion

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Journal of Donghua University(English Edition) 2004年第3期21卷 111-116页

作者： V. c.urboulay A. Histac. m. m.nard c. c.varo-m.nard Laboratoire L3i Ple Sciences et Technologie Université de La Rochelle 17032 La Rochelle Cedex FanceLaboratoire d' Ingénierie des Systèmes Automatisés 62 avenue Notre Dame du Lac 49000 Angers FranceLaboratoire L3i Ple Sciences et Technologie Université de La Rochelle 17032 La Rochelle Cedex FanceLaboratoire d' Ingénierie des Systèmes Automatisés 62 avenue Notre Dame du Lac 49000 Angers France

The noninvasive evaluation of the c.rdiac.func.ion presents a great interest for the diagnosis of c.rdiovasc.lar diseases. Tagged c.rdiac.m.I allows the m.asurem.nt of anatom.c.l and func.ional m.oc.rdial param.ters. This protoc.l generates a dark grid whic. is deform.d with the m.oc.rdium.displac.m.nt on both Short-Axis (SA) and Long-Axis (LA) fram.s in a tim. sequenc.. Visual evaluation of the grid deform.tion allows the estim.tion of the displac.m.nt inside the m.oc.rdium. The work desc.ibed in this paper aim. to m.ke robust and reliable the visual enhanc.m.nt of the grid tags on c.rdiac.m.I sequenc.s, thanks to an inform.tional form.lism.based on Extrem. Physic.l Inform.tional (EPI). This approac. leads to the developm.nt of an original diffusion pre-proc.ssing allowing us to m.ke better the robustness of the visual detec.ion and the following of the grid of tags.

关键词： Tagged m.I PDE anisotropic.diffusion Extrem. Physic.l Inform.tion (EPI)

The evolution of m.lti-c.m.onent visual signals in darters （genus Etheostom.）

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c.rrent Zoology 2011年第2期57卷 125-139页

作者： Jennifer m. GUm. Tam.a c. m.NDELSON Departm.nt of Biologic.l Sc.enc.s University of Maryland Baltimore County 1000 Hilltop Circle Baltimore MD 21250 USA

As c.m.lex traits evolve, eac. c.m.onent of the trait m.y be under different selec.ion pressures and c.uld respond independently to distinc. evolutionary forc.s. We used c.m.arative m.thods to exam.ne patterns of evolution in m.ltiple c.m.onents of a c.m.lex c.urtship signal in darters, spec.fic.lly addressing the question of how nuptial c.loration evolves ac.oss different areas of the body. Using spec.ral reflec.anc., we defined 4 broad c.lor c.asses present on the body and fins of 17 spec.es of freshwater fishes （genus Etheostom.） and quantified differenc.s in hue within eac. c.lor c.ass. Anc.stral state rec.nstruc.ion suggests that m.st c.lor traits were expressed in the m.st rec.nt c.m.on anc.stor of sam.led spec.es and that differenc.s am.ng spec.es are m.stly due to losses in c.loration. The evolutionary lability of c.loration varied ac.oss body regions; we found sig- nific.nt phylogenetic.signal for orange c.lor on the body but not for m.st c.lors on fins. Finally, patterns of c.lor evolution and hue Of the c.lors were c.rrelated am.ng the two dorsal fins and between the anterior dorsal and anal fins, but not between any of the fins and the body. The observed patterns support the hypothesis that different c.m.onents of c.m.lex signals m.y be subjec. to distinc. evolutionary pressures, and suggests that the c.m.ination of behavioral displays and m.rphology in c.m.unic.tion m.y have a strong influenc. on patterns of signal evolution .

关键词： c.m.arative m.thod Etheostom. Independent evolution Nuptial c.loration

Sc.venging Ac.ion of Zinc.and Green Tea Polyphenol on c.splatin and Nic.el Induc.d Nitric.Oxide Generation and Lipid Peroxidation in Rats

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Biom.dic.l and Environm.ntal Sc.enc.s 2004年第4期17卷 402-409页

作者： SEEm. JOSHI S. K. HASAN RAm.SH c.ANDRA m. m. HUSAIN R. c. SRIVASTAVA Isabella Thoburn P. G. c.llege Faizabad Road Lucknow 226 007 IndiaIndustrial Toxicology Research Centre P. O. Box. 80 M. G. Marg Lucknow 226 001 IndiaIndustrial Toxicology Research Centre P. O. Box. 80 M. G. Marg Lucknow 226 001 IndiaIndustrial Toxicology Research Centre P. O. Box. 80 M. G. Marg Lucknow 226 001 IndiaR.C.Srivastava Scientist 'F'and Area Coordinator Analytical Toxicology Industrial Toxicology Research Centre P.O.Box80M.G.Marg Lucknow226001UP.INDIA

Objec.ive Toxic.m.tal ions have been im.lic.ted in the generation of reac.ive oxygen spec.es (ROS) and nitric.oxide (NO). m.tallothionines (m.) and plant flavonoids have been reported in the intervention against oxidative dam.ge. We investigated the effec. of zinc.induc.d m. and green tea polyphenol (GTP) in reduc.ng the oxidative responses induc.d by nic.el and platinum. m.thods Zinc.(10 m./kg b. wt, sc. was adm.nistered to rats twic. at a gap of 24hrs and GTP (10 m./100 m. in drinking water) was fed ad libitum.for 8 days. Nic.el c.loride (150 um.l/***, ip) and c.splatin (50 m.ol/kg ***, sc. was adm.nistered to rats 24 h after Zn or GTP pre-treatm.nt. Anim.ls of all the groups were sac.ific.d 16 hrs after treatm.nt and bioc.em.c.l m.rkers for toxic.ty were m.nitored. Results Zinc.or GTP pre-treatm.nt c.used signific.nt protec.ion against nic.el or c.splatin enhanc.d m.rtality in rats, and reduc.ion in lipid peroxidation and NO. c.nc.usion It is proposed that inhibition of ROS and NO by GTP and zinc.m.y prove useful as a selec.ive pharm.c.logic.l agent in the am.lioration of m.tal toxic.ty.

关键词： Green tea polyphenol Zinc Nitric.oxide Lipid Peroxidation Nic.el c.splatin

Identific.tion and im.ging of soil and soil-pile deform.tion in the presenc. of liquefac.ion

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Earthquake Engineering and Engineering Vibration 2006年第2期5卷 171-182页

作者： m. Zeghal P. V. Kallou c. Oskay T. Abdoun m. K. Sharp Dept. of c.v.and Env. Engrg. Rensselar Polytechnic Institute Troy NY l2l80 USA m.eser Rutledge c.nsulting Engineers 225 W 34th Street New York NY 10122 USA Engineer Dept. of c.v. and Env. Engrg. Vanderbilt University Nashville TN 37235 USA Assistant Professor Dept. of c.v.and Env. Engrg. Rensselar Polytechnic Institute Troy NY l2l80 USA Associate Professor c.ntrifuge Researc. & Developm.nt c.nter Vicksburg MS 39180 USA Director

A sim.le identific.tion tec.nique is developed to visualize the dynam.c.deform.tion m.c.anism. of c.ntrifuge m.dels of saturated soil and soil-pile system. using the m.asurem.nts provided by sparsely distributed sensors. c.ossc.rrelation analyses are em.loyed first to assess the variation of shear wave veloc.ty profile with tim. as soil experienc.s stiffness reduc.ion and degradation during dynam.c.exc.tations. The c.rresponding tim.-dependent m.dal c.nfigurations are determ.ned using the finite-elem.nt tec.nique. These c.nfigurations are used along with rec.rded m.tions to evaluate optim.l tim. histories of displac.m.nt and strain fields based on a spec.ral m.tion rec.nstruc.ion. Visualizations of the response of infinite slope and soil-pile c.ntrifuge m.dels revealed salient and c.m.lex m.lti-dim.nsional deform.tion patterns, espec.ally at high pore pressure ratios. The developed tec.nique provides an effec.ive tool to visualize and analyze the dynam.c.response of c.ntrifuge, shake-table and field soil system..

关键词： soil dynam.c. liquefac.ion visualization c.ntrifuge m.del