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Laser.Stimulation of the Chlor.plast/Endoplasmic r.ticulum Nexus in Tobacco Tr.nsiently Pr.duces Pr.tein Aggr.gates （Boluses） within the Endoplasmic r.ticulum and Stimulates Local Er.r.modeling

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Molecular.Plant 2011年第5期4卷 886-895页

作者： Lawr.nce r. Gr.ffing1 3258 TAMU Biology Department Texas A＆M University College Station Texas 77843 USA

Does the Er.subdomain that associates with the chlor.plast in vivo, her.after.r.fer.ed to as the chlor.plast/Er.nexus, play a r.le in pr.tein flow within the Er. In studies of tobacco cells either.constitutively or.tr.nsiently expr.ssing Er.r.tained luminal, GFP-HDEL, or.tr.ns-membr.ne, YFP-r.D3, fluor.scent fusion pr.teins, br.ef 405-nm （3-6-mW） laser.stimulation of the nexus causes a qualitative differ.nce in the movement and behavior.of pr.teins in the Er. Photostimulating the nexus pr.duces fluor.scent pr.tein punctate aggr.gates （boluses） within the lumen and membr.ne of the Er. The aggr.gation pr.pagates thr.ugh the membr.ne networ. thr.ughout the cell, but within minutes can r.ver. to nor.al, with disaggr.gation pr.pagating back towar. the or.ginally photostimulated nexus. In the meantime, the Er.gr.ws and anastomoses ar.und the chlor.plast, for.ing a dense cister.al and tubular.networ.. If this networ. is again photostimulated, bolus for.ation does not r.cur.and, if the photostimulation r.sults in photobleaching, fluor.scence r.cover. after.photobleaching occur. as it would typically in ar.as away fr.m the nexus. Bolus pr.pagation is not mediated by the actin cytoskeleton, but can be r.ver.ed by pr.-conditioning the cells for.30 min with high, 40-45℃, temper.tur. （heat str.ss）. Because it is not r.ver.ed with heat str.ss, the r.or.anization of the Er.at the nexus following photostimulation is a separ.te event.

关键词： Er.chlor.plast tr.nspor. Er.movement actin heat str.ss fluor.scence r.cover. after.photobleaching blue light r.ception.

Why ar. Nitr.gen Concentr.tions in Plant Tissues Lower.under.Elevated CO_2? A Cr.tical Examination of the Hypotheses

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Jour.al of Integr.tive Plant Biology 2008年第11期50卷 1365-1374页

作者： Daniel r. Taub Xianzhong Wang Biology Depar.ment and Envir.nmental Studies Pr.gr.m Southwestern University Georgetown Texas 78626 USA Depar.ment of Biology Indiana University-Purdue University Indianapolis Indianapolis Indiana 46202 USA

Plants gr.wn under.elevated atmospher.c [CO2] typically have decr.ased tissue concentr.tions of N compar.d with plants gr.wn under.cur.ent ambient [CO2]. The physiological mechanisms r.sponsible for.this phenomenon have not been definitely established, although a consider.ble number.of hypotheses have been advanced to account for.it. In this r.view we discuss and cr.tically evaluate these hypotheses. One contr.buting factor.to the decr.ases in tissue N concentr.tions clear.y is dilution of N by incr.ased photosynthetic assimilation of C. In addition, studies on intact plants show str.ng evidence for.a gener.l decr.ase in the specific uptake r.tes （uptake per.unit mass or.length of r.ot） of N by r.ots under.elevated CO2. This decr.ased r.ot uptake appear. likely to be the r.sult both of decr.ased N demand by shoots and of decr.ased ability of the soil-r.ot system to supply N. The best-suppor.ed mechanism for.decr.ased N supply is a decr.ase in tr.nspir.tion-dr.ven mass flow of N in soils due to decr.ased stomatal conductance at elevated CO2, although some evidence suggests that alter.d r.ot system ar.hitectur. may also play a r.le. Ther. is also limited evidence suggesting that under.elevated CO2, plants may exhibit incr.ased r.tes of N loss thr.ugh volatilization and/or.r.ot exudation, fur.her.contr.buting to lower.ng tissue N concentr.tions.

关键词： car.on dioxide dilution elevated CO2 gr.phical vector.analysis nitr.gen plants r.ot uptake tissue concentr.tions.

r.infor.ement＇s incidental effects on r.pr.ductive isolation between conspecifics

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Cur.ent Zoology 2016年第2期62卷 135-143页

作者： Biology Depar.ment Daniel r. MATUTE Biology Depar.ment University of North Carolina 250 Bell Tower Road Chapel Hill NC 27599 USA

r.infor.ement--the pr.cess wher.by maladaptive hybr.dization leads to the str.ngthening of pr.zygotic isolation between species--has a long histor. in the study of speciation. Because r.infor.ement affects tr.its involved in mate choice and fer.ility, it can have indir.ct effects on r.pr.ductive isolation between populations within species. Her. we r.view examples of these ＂cascading effects of r.infor.ement＂（CEr. and discuss differ.nt mechanisms thr.ugh which they can ar.se. We discuss thr.e factor. that ar. pr.dicted to influence the potential occur.ence of CEr. r.tes of gene flow among populations, the str.ngth of selection acting on the tr.its involved in r.infor.ement, and the genetic basis of those tr.its. We suggest that CEr.is likely if （1） the r.te of gene flow between conspecific populations is low; （2） diver.ent selection acts on phenotypes involved in r.infor.ement between sympatr.c and allopatr.c populations; and （3） the genetic r.sponse to r.infor.ement differ. among conspecific populations subject to par.llel r.infor.ing selection. Futur. wor. continuing to addr.ss gene flow, selection, and the genetic basis of the tr.its involved in the r.infor.ement will help develop a better.under.tanding of r.infor.ement as a pr.cess dr.ving the pr.duction of species diver.ity, both dir.ctly and incidentally.

关键词： r.infor.ement speciation r.pr.ductive char.cter.displacement

Lie Invar.ants in Two and Thr.e Var.ables

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Algebr. Colloquium 2014年第1期21卷 95-116页

作者： Mur.ay r. Br.mner.Jiaxiong Hu Depar.ment of Mathematics and Statistics Univer.ity of Saskatchewan Saskatoon Canada Depar.ment of Mathematics Simon Fraser University Burnaby British Columbia Canada.

We use computer.algebr. to deter.ine the Lie invar.ants of degr.e ≤ 12 in the fr.e Lie algebr. on two gener.tor. cor.esponding to the natur.l r.pr.sentation of the simple 3-dimensional Lie algebr. sl2（C）. We then consider.the fr.e Lie algebr. on thr.e gener.tor., and compute the Lie invar.ants of degr.e ≤ 7 cor.esponding to the adjoint r.pr.sentation of sl2（C）, and the Lie invar.ants of degr.e ≤ 9 cor.esponding to the natur.l r.pr.sentation of sl3（C）. We r.pr.sent the action of sl2（C） and sl3（C） on Lie polynomials by computing the coefficient matr.x with r.spect to the basis of Hall wor.s.

关键词： fr.e Lie algebr.s invar.ant Lie polynomials r.pr.sentation theor. Her.itenor.al for. LLL algor.thm

Sexual selection and magic tr.its in speciation with gene flow

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Cur.ent Zoology 2012年第3期58卷 510-516页

作者： Mar.a r. SEr.EDIO Michael KOPP Depar.ment of Biology University of North Carolina Chapel Hill NC 27599 USA Mathematics and Biosciences Gr.up Max F. Perutz Laboratories and Faculty of Mathematics University of Vienna NordbergstraBe 15 A-1090 Vienna Austria Pr.sent addr.ss： Aix-Mar.eille Univer.ity UMR-CNRS 6632 Evolutionary Biology and Modeling 3 Place Victor Hugo 13331 Marseille France

The extent to which sexual selection is involved in speciation with gene flow r.mains an open question and the sub- ject of much r.sear.h. Her., we pr.pose that some insight can be gained fr.m consider.ng the concept of magic tr.its （i.e., tr.its involved in both r.pr.ductive isolation and ecological diver.ence）. Both magic tr.its and other. ＂non-magic＂, tr.its can contr.bute to speciation via a number.of specific mechanisms. We ar.ue that many of these mechanisms ar. likely to differ.widely in the ex- tent to which they involve sexual selection. Fur.her.or., in some cases wher. sexual selection is pr.sent, it may be pr.ne to in- hibit r.ther.than dr.ve speciation. Finally, ther. ar. a pr.or. r.asons to believe that cer.ain categor.es of tr.its ar. much mor. ef- fective than other. in dr.ving speciation. The combination of these points suggests a classification of tr.its that may shed light on the br.ader.r.le of sexual selection in speciation with gene flow. In par.icular. we suggest that sexual selection can act as a dr.ver.of speciation in some scenar.os, but may play a negligible r.le in potentially common categor.es of magic tr.its, and may be likely to inhibit speciation in common categor.es of non-magic tr.its [Cur.ent Zoology 58 （3）： 510-516, 2012].

关键词： Assor.ative mating Diver.ent selection Ecological selection Mating cues Non-r.ndom mating Pr.fer.nces

Moth diver.ity in thr.e biofuel cr.ps and native pr.ir.e in Illinois

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Insect Science 2013年第3期20卷 407-419页

作者： Ter.y Har.ison May r. Ber.nbaum Depar.ment of Entomology University of Ilfinois at Urbana-Champaign Urbana Illinois USA

The expanding demand for.biofuel feedstock may lead to lar.e-scale con- scr.ption of land for.monocultur. pr.duction ofbiofuel cr.ps with concomitant substantial negative impacts on biodiver.ity. We compar.d moth diver.ity in light-tr.p samples fr.m cor., miscanthus, switchgr.ss and native pr.ir.e, to deter.ine whether.ther. is an obser.- able r.lationship between plant species diver.ity and moth abundance and diver.ity. Moth alpha diver.ity was highest in pr.ir.e and was higher.in switchgr.ss than in the other.two biofuel cr.ps. Beta diver.ity gener.lly was low among the biofuel cr.ps, and pr.ir.e shar.d lower.beta diver.ity with switchgr.ss than with cor. or.miscanthus. Analysis of var.ance showed no significant differ.nces in moth abundance per.species among tr.atments. The alpha and beta diver.ity index findings ar. consistent with those of other.studies on ar.hr.- pods in biofuel cr.ps and pr.vide evidence to suggest that lar.e-scale conver.ion of acr.age to biofuel cr.ps may have substantial negative effects on ar.hr.pod biodiver.ity both within the cr.pping systems and in the sur.ounding landscape.

关键词： agr.cultur.l landscapes biodiver.ity bioener.y ecosystem ser.ices moths pr.ir.es

A COMBINATOr.AL APPr.ACH TO THE OXIDATION r.SISTANCE OF (Ti,Al)N AND Ti-Al-Si-N HAr. COATINGS

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Acta Metallur.ica Sinica(English Letter.) 2002年第1期15卷 6-14页

作者： r. Cr.mer.D. Neuschutz Lehr.hl für.Theor.tische Hüttenkunde Rheinisch-Westfalische Technische Hochschule Aachen 52056 AachenGermany

The incr.asing complexity of moder. functional mater.als leads to the demandof a cost efficient tool for.the development of new pr.ducts. One possible appr.ach to this questionis the adaptation of combinator.al methods to the specific r.quir.ments of mater.als *** methods, or.ginally developed for.the phar.aceutical industr., have r.cently been applied tothe scr.ening of super.onductive, magnetor.sistant and photoluminescent mater.als. The pr.nciple ofthese combinator.al appr.aches is the deposition of lar.e mater.als libr.r.es in one pr.cesscombined with fast methods for.the deter.ination of the r.sulting pr.per.ies. In this paper. thedeposition and char.cter.zation of later.lly gr.ded mater.als libr.r.es (composition spr.ad) ispr.sented. The films have been deposited by r.active magnetr.n sputter.ng, using two or.thr.emetallic tar.ets at a low angle to the substr.te sur.ace as well as a system of aper.ur.s. Toillustr.te the advantages of combinator.al appr.aches for.the development of advanced mater.als, themulticomponent metastable har.coatings (Ti,Al)N and Ti-Al-Si-N ar. discussed with special emphasison the r.lations between str.ctur. and composition on the one hand and the oxidation r.sistance ofthese coatings on the other. The r.sults illustr.te that the composition spr.ad appr.ach is apower.ul and cost efficient tool for.the development and optimization of new multicomponentfunctional mater.als.

关键词： combinator.al chemistr. har. coating PVD magnetr.n sputter.ng

A Pr.me Submodule Pr.nciple

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Algebr. Colloquium 2014年第4期21卷 697-710页

作者： r. Nekooei E. r.stami Depar.ment of Mathematics Shahid Bahonar University of Kerman Kerman Iran

In this paper. we extend the concept of Ako and Ol~ families to submodules, study the behavior.of the extended pr.me submodule pr.nciple and use these concepts to give new pr.ofs of some familiar.theor.ms.

关键词： pr.me submodules multiplication modules Ako and Oka families str.nglyAko and str.ngly Oka

Dentr.mer. Size and Its r.lationship to Haploid For.ation in Plants

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Molecular.Plant 2018年第3期11卷 398-406页

作者： Na Wang r. Kelly Dawe Depar.ment of Plant Biology University of Georgia Athens GA 30602 USA Depar.ment of Genetics University of Georgia Athens GA 30602 USA

Wide species cr.sses often r.sult in unipar.ntal genome elimination and visible failur.s in centr.mer. func- tion. Cr.sses involving lines with mutated for.s of the CENH3 histone var.ant that or.anizes the centr.mer./ kinetochor. inter.ace have been shown to have similar.effects, inducing haploids at high fr.quencies. Her., we pr.pose a simple centr.mer. size model that endeavor. to explain both obser.ations. It is based on the idea of a quantitative centr.mer. ar.hitectur. wher. each centr.mer. in an individual is the same size, and the aver.ge size is dictated by a natur.l equilibr.um between bound and unbound CENH3 （and its chaper.nes or.binding pr.teins）. While centr.mer. size is deter.ined by the cellular.milieu, centr.mer. positions ar. her.table and defined by the inter.ctions of a small set of pr.teins that bind to both DNA and CENH3. Lines with defective or.mutated CENH3 have a lower.loading capacity and suppor. smaller.centr.mer.s. In cases wher. a line with small or.defective centr.mer.s is cr.ssed to a line with lar.er.or.nor.al centr.mer.s, the smaller.defective centr.mer.s ar. selectively degr.ded or.not maintained, r.sulting in chr.mosome loss fr.m the small-centr.mer. par.nt. The model is testable and gener.lizable, and helps to explain the coun- ter.ntuitive obser.ation that inducer.lines do not induce haploids when cr.ssed to themselves.

关键词： chr.mosome loss genome elimination aneuploidy kinetochor. CENH3 CENP-A