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Dissim.lar titanium.alum.num.friction stir welding lap joints by experim.nts and num.rical sim.lation

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Advances in m.nufacturing 2016年第4期4卷 287-295页

作者： G. Buffa m. De lisi E. Sciortino l. Fratini epartm.nt of Chem.cal Management Computer and Mechanical Engineering University of Palermo Viale delle Scienze 90128 Palermo Italy

Dissim.lar stir welding （FSW） lap joints were produced by friction out of Ti6A14V titanium.alloy and AA2024 alum.num.alloy sheets. The joints, welded with varying tool rotation and feed rate, were studied by ana- lyzing the m.xim.m.shear strength, Vickers m.crohardness and optical observations. A dedicated num.rical m.del, able to take into account the presence of the two different alloys, was used to highlight the effects of the process param.ters on tem.erature distribution, strain distribution, and m.terial flow. The com.ined analysis of experim.ntal m.asurem.nts and num.rical predictions allowed explaining the effects of tool rotation and feed rate on the m.terial flow. It was found that tool rotation had a larger im.act on the joint effectiveness with respect to feed rate. A com.etition between m.terial m.xing and heat input occurs with increasing tool rotation, resulting in higher joint strength when lower values of tool rotation are used.

关键词： Finite elem.nt m.thod (FEm. Ti6A14V AA2024 Friction stir welding (FSW) lap joint

An underlying geom.trical m.nifold for Ham.ltonian m.chanics

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Frontiers of physics 2017年第1期12卷 123-131页

作者： l. P. Horwitz A. Yahalom.J. levitan m. lewkowicz School of Physics Tel Aviv University Ramat Aviv 69978 Israel Departm.nt of Physics Bar llan University Ramat Gan 52900 Israel Departm.nt of Physics Ariel University Ariel 40700 Israel Departm.nt of Electrical and Electronic Engineering Ariel University Ariel 40700 Israel

We show that there exists an underlying m.nifold with a conform.l m.tric and com.atible connection form. and a m.tric type Ham.ltonian （which we call the geom.trical picture）, that can be put into correspondence with the usual Ham.lton-lagrange m.chanics. The requirem.nt of dynam.cal equiva- lence of the two types of Ham.ltonians, that the m.m.nta generated by the two pictures be equal for all tim.s, is sufficient to determ.ne an expansion of the conform.l factor, defined on the geom.trical coordinate representation, in its dom.in of analyticity with coefficients to all orders determ.ned by functions of the potential of the Ham.ltonian-lagrange picture, defined on the Ham.lton-lagrange coordinate representation, and its derivatives. Conversely, if the conform.l function is known, the potential of a Ham.lton-lagrange picture can be determ.ned in a sim.lar way. We show that arbi- trary local variations of the orbits in the Ham.lton-lagrange picture can be generated by variations along geodesics in the geom.trical picture and establish a correspondence which provides a basis for understanding how the instability in the geom.trical picture is m.nifested in the instability of the the original Ham.ltonian m.tion.

关键词： geom.trical Ham.ltonian stability analysis coordinate m.pping Riem.nn-Euclidean Ham.ltonian equivalence

The total cross sections of the ^(11)B(α,n)^(14N) and the ^(10)B(α,n)^(13)N reactions between 2 and 6 m.V

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Nuclear Science and Techniques 2017年第8期28卷 111-116页

作者： R. m. Prior m. C. Spraker R. H. France S. Stave m. W. Ahm.d H. J. Karwowski J. m. m.eller l. S. m.ers H. R. Weller University of North Georgia Dahlonega GA 30597 USA Georgia College & State University MilledgevilleGA 31061 USA Duke University Durham NC 27708 USA Triangle Universities Nuclear laboratory DurhamNC 27708 USA University of North Carolina Chapel Hill NC 27599 USA Present Address: Bluffton University Bluffton OH 45817USA

There is considerable interest in potential aneutronic fusion reactors. One possible reaction is^(11)B(p,a)***, the em.tted alpha particles are energetic enough to generate neutrons by interacting with boron inside the reactor through the ^(11)B(α,n)^(14N) and ^(10)B(α,n)^(13)N *** aid in evaluating neutron production within this potential aneutronic reactor, the total cross sections were m.asured for the ^(11)B(α,n)^(14N) reaction between 2 and 6 m.V and for the ^(10)B(α,n)^(13)N reaction between 2 and 4.8 m.V. The results are presented and com.ared with previously reported results.

关键词：聚变反应堆 m.V 总截面核反应堆中子反应器 α粒子电子

Baryon resonance analysis from.m.ID

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Chinese Physics C 2009年第12期33卷 1069-1076页

作者： l. Tiator D. Drechsel S.S. Kam.lov m. Vanderhaeghen Institut fr Kernphysik Universitt Mainz D-55099 Mainz Germany Bogoliubov laboratory for Theoretical Physics JINR Dubna 141980 Moscow Region Russia

The unitary isobar m.del m.ID2007 has been used to analyze the recent data of pion electroproduction. The m.del contains all four-star resonances in the region below W = 2 GeV and both single-Q2 and Q2 dependent transition form.factors could be obtained for the Delta, Roper, D13（1520）, S11 （1535）, S31 （1620）, $11（1650）, D15（1675）, F15（1680） and P13（1720）. From.the com.lete world data base, including also π data on the neutron, also Q2 dependent neutron form.factors are obtained. For all transition form.factors we also give convenient num.rical param.terizations that can be used in other reactions. Furtherm.re, we show how the transition form.factors can be used to obtain em.irical transverse charge densities and our first results are given for the Roper, the S11 and D13 resonances.

关键词： pion photo- and electroproduction non-strange baryons transition form.factors

Genetic basis for body size variation between an anadrom.us and two derived lacustrine populations of threespine stickleback Gasterosteus aculeatus in southwest Alaska

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Current Zoology 2016年第1期62卷 71-78页

作者： Ella BOWlES Rebecca A. JOHNSTON Stevi l. VANDERZWAN Sean m. ROGERS Departm.nt of Biological Sciences University of Calgary 2500 University Dr. N.W. Calgary Alberta T2N 1N4Canada

Body size is a highly variable trait am.ng geographically separated populations. Size-assortative reproductive isolation has been linked to recent adaptive radiations of threespine stickleback （Gasterosteus aculeatus） into freshwater, but the genetic basis of the com.only found size differ- ence between anadrom.us and derived lacustrine sticklebacks has not been tested. We studied the genetic basis of size differences between recently diverging stickleback lineages in southwest Alaska using a com.on environm.nt experim.nt. We crossed stickleback within one anadrom.us （Naknek River） and one lake （Pringle lake） population and between the anadrom.us and two lake populations （Pringle and JoJo lakes）, and raised them.in a salinity of 4-6 ppt. The F1 anadrom.us and freshwater form. differed significantly in size, whereas hybrids were interm.diate or exhibited dom.nance toward the anadrom.us form. Additionally, the size of freshwater Fls differed from.their wild counterparts, with within-population Fls from.Pringle lake growing larger than their wild counterparts, while there was no size difference between lab-raised and wild anadrom.us fish. Sexual dim.rphism.was always present in anadrom.us fish, but not in freshwater, and not always in the hybrid crosses. These results, along with parallel changes am.ng anadrom.us and fresh- water form. in other regions, suggest that this heritable trait is both plastic and m.y be under di- vergent and/or sexual selection.

关键词： adaptation body size com.on garden genetic basis threespine stickleback.

Investigation of protein-styrene oxide adducts as a m.lecular biom.rker of hum.n exposed to styrene

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Journal of Environm.ntal Sciences 2001年第4期13卷 391-397页

作者： liu, S.-F. Fang, Q.-m. Jin, Z.-l. Rappaport, m.S. Res. Cntr. Eco-Environm.ntal Sci. Chinese Academy of Sciences Beijing 100085 China

Hem.globin-styrene oxide adducts in blood have been studied as a m.lecular biom.rker of worker exposed to styrene. Determ.nation of protein-styrene oxide adducts in different biological sam.les with m.dified Raney-Ni procedure is described in this paper. The following biological sam.les have been investigated: fresh rat blood reacted with styrene oxide in vitro: rat blood reacted with styrene or styrene oxide in vivo: vein blood from.workers exposed to styrene in two factories. The data showed that there was a good linear dose-response relationship between reacting dose of styrene oxide or styrene and am.unt of protein-styrene oxide adducts in both in vitro and in vivo experim.nts. For hum.n sam.les, a dose-response relationship between protein adducts and styrene exposure can be found in glass fiber factory, but not in piano m.nufacture plant.

关键词： Blood Drug dosage Glass fibers Hem.globin m.nufacture Oxides Proteins Styrene

Interaction between cannabinoid and nucleotide system. as a new m.chanism.of signaling in retinal cell death

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Neural Regeneration Research 2019年第12期14卷 2093-2094页

作者： Hércules R. Freitas Ricardo A. m. Reis Ana l. m. Ventura Guilherm. R. Franca laboratory of Neurochem.stry Institute of Biophysics Carlos Chagas Filho Universidade Federal do Rio de Janeiro Rio de Janeiro RJ Brazil School of Health Sciences Centro Universitário IBMR Rio de Janeiro RJ Brazil laboratory of Neurochem.stry Institute of Biology Universidade Federal Fluminense Niterói RJ Brazil Biom.dical Institute Departament of Physiological Sciences/ Pharmacology Universidade Federal do Estado do Rio de Janeiro Rio de Janeiro RJ Brazil

Nervous system.em.rges from.com.lex signaling interactions where extrinsic (neurotransm.tters and trophic factors, am.ng others) and intrinsic factors (transcription factors) interplay in the developing tissue to control gene activity prom.ting chronic changes in cell genesis, m.gration, differentiation and death. The retinal m.croenvironm.nt is regulated by a broad variety of chem.cals, including endocannabinoids and nucleotides that m.dulate em.ryonic progenitor-neuron-m.ller glia signaling in very early developing or pathophysiological conditions.

关键词： Interaction nucleotide system. cell death

Wild dogm. II： The role and im.lications of wild dogm. for wild dog m.nagem.nt in Australia

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Current Zoology 2011年第6期57卷 737-740页

作者： Benjam.n l. AllEN Richard m. ENGEm.N lee R. AllEN The University of Queensland School of Animal Studies Warrego Highway Gatton QLD 4343 National Wildlife Research Centre 4101 l_aPorte Avenue Fort Collins CO 80521-2154 USA. Richard.M.Engeman@aphis.usda.gov Biosecurity Queensland Robert Wicks Pest Animal Research Centre Tor Street Toowoomba QLD 4350. Lee.Allen@ deedi.qld.gov.au

The studies of Allen （2011） and Allen et al. （2011） recently exam.ned the m.thodology underpinning claim. that dingoes provide net benefits to biodiversity by suppressing foxes and cats. They found m.st studies to have design flaws and/or observational m.thods that preclude valid interpretations from.the data, describing m.st of the current literature as ＇wild dogm.＇. In this short supplem.nt, we briefly highlight the roles and im.lications of wild dogm. for wild dog m.nagem.nt in Australia. We discuss nom.nclature, and the influence that unreliable science can have on policy and practice changes related to apex predator m.nagem.nt

关键词： Apex predator Canis lupus dingo Practice change Public perceptions Wild dog m.nagem.nt

m.ltiscale m.chanobiology m.deling for surgery assessm.nt

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Acta m.chanica Sinica 2012年第4期28卷 1186-1202页

作者： m. Garbey B. l. Bass S. Berceli Dept. of Com.uter Science University of Houston USA The Methodist Institute for TechnologyInnovation and Education Houston TX USA Dept. of Surgery The Methodist Hospital Houston TX USA The Methodist Institute for TechnologyInnovation and Education Houston TX USA Dept. of Surgery University of Florida

This paper discusses som. of the concept of m.deling surgery outcom.. It is also an attem.t to offer a road m.p for progress. This paper m.y serve as a com.on ground of discussion for both com.unities i.e surgeons and com.utational scientist in its broadest sense. Predicting surgery outcom. is a very difficult task. All patients are different, and m.ltiple factors such as genetic, or environm.nt conditions plays a role. The difficulty is to construct m.dels that are com.lex enough to address som. of these significant m.ltiscale elem.nts and sim.le enough to be used in clinical conditions and calibrated on patient data. We will pro- vide a m.ltilevel progressive approach inspired by two applications in surgery that we have been working on. One is about vein graft adaptation after a transplantation, the other is the recovery of cosm.sis outcom. after a breast lum.ectom.. This work, that is still very m.ch in progress, m.y teach us som. lessons. We are convinced that the digital revolution that is transform.ng the working environm.nt of the surgeon m.kes closer collaboration between surgeons and com.utational scientist unavoidable. We believe that ＂com.utational surgery＂ will allow the com.unity to develop predictive m.del of the surgery outcom. and greatprogresses in surgery procedures that goes far beyond the operating room.procedural aspect.

关键词： m.ltiscale m.chanobiology Surgery assessm.nt Breast cancer Vascular Adaptation