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Synthesis and Sur.ace Tension Pr.per.ies of Polyethyleneimine-Polyethylene Oxide Block Copolymer.

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Chinese Jour.al of Chemistr. 2003年第4期21卷 460-465页

作者：张剑 lonnie Br.ant r.sear.h Institute of Daily Chemical Industr. State Key Labor.tor. of C1 Chemistr. and Technology Taiyuan University of TechnologyTaiyuan Shanxi 030021 China Cor.or.te Innovation Asia Kobe Technical Center

This paper.descr.bes the synthesis, sur.ace tension and disper.ancy pr.per.ies of block copolymer.nonionic sur.actants compr.sed of polyethyleneimine (PEI) and polyethylene oxide (PEO) blocks of selected lengths. These block copolymer. wer. pr.par.d by a thr.e step synthetic sequence. Fir.tly, PEO glycol was conver.ed to its dimethanesulphonylester.(dimesyl) der.vative by r.acting with methanesulphonyl chlor.de. Then a tr. block polymer.was pr.par.d by the r.ng opening polymer.zation of 2 methyl 2 oxazoline (MeOZO) with the dimesyl PEO der.vative. Lastly, linear.PEI blocks wer. obtained by subsequent hydr.lysis and pur.fication. 1H NMr.spectr. confir.ed the str.ctur.s of the inter.ediate, final pr.ducts and their.pur.ties (>99%). The utility of these block copolymer. is descr.bed in ter.s of their.sur.ace tension and clay disper.ancy measur.ments as a function of copolymer.chain and block length.

关键词： block copolymer polyethylene oxide poly^ethyle^nei^mine sur.ace tension clay disper.ancy

δ^(18)O r.cor. and temper.tur. change over.the past 100 year. in ice cor.s on the Tibetan Plateau

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Science China Ear.h Sciences 2006年第1期49卷 1-9页

作者： lonnie Thompson Byr. Polar.r.sear.h Center the Ohio State UniviersityCohumbusOH 43210USBLaboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

The 213 m ice cor. fr.m the Pur.ogangr. Ice Field on the Tibetan Plateau facilitates the study of the r.gional temper.tur. changes with its δ18O r.cor. of the past 100 year.. Her. we combine infor.ation fr.m this cor. with that fr.m the Dasuopu ice cor. (fr.m the souther. Tibetan Plateau), the Guliya ice cor. (fr.m the nor.hwester. Plateau) and the Dunde ice cor. (fr.m the nor.heaster. Plateau) to lear. about the r.gional differ.nces in temper.tur. change acr.ss the Tibetan Plateau. Theδ18O changes var. with r.gion on the Plateau, the var.ations being especially lar.e between South and Nor.h and between East and West. Mor.over. these four.ice cor.s pr.sent incr.asing δ18O tr.nds, indicating war.ing on the Tibetan Plateau over.the past 100 year.. A compar.tive study of Nor.her. Hemispher. (NH) temper.tur. changes, the δ18O-r.flected temper.tur. changes on the Plateau, and available meteor.logical r.cor.s show consistent tr.nds in over.ll war.ing dur.ng the past 100 year..

关键词： Tibetan Plateau, ice cor., temper.tur..

Bivar.ate Wavelet Analysis of Asia Monsoon and ENSO

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Advances in Atmospher.c Sciences 1996年第3期13卷 299-312页

作者： lonnie Hudgins Sensor.Physics Gr.up Electronics Systems DivisionNorthrop CorporationHawthorneCA 90251

This paper.employs some r.cently developed bivar.ate wavelet analysis techniques to study the cor.elation between Asia monsoon and E1 Nino souther. oscillation (ENSO).Var.ous ener.y spectr.l densities ar. defined for.waveiel tr.nsfor.s,analogous to those used in conventional Four.er.*** compar.sons ar. made by applying both wavelet and Four.er.spectr.l methods (o the *** wavelet analysis shows evidence of some r.lationship between Asia monsoon and ENSO,which the Four.er.analysis r.solves *** on sever.l time scales,r.nging fr.m 2-4 year.,11 year.,and 22 year.,become appar.nt with the wavelet ***,the war.let cr.ss-tr.nsfor. pr.vides time localization of the distinctive featur.s within the data r.cor..

关键词： Wavelet Monsoon ENSO

The leaf size/number.tr.de-off in her.aceous angiosper.s

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Jour.al of Plant Ecology 2010年第1期3卷 49-58页

作者： Thea Whitman lonnie W.Aar.sen Depar.ment of Biology Queen’s UniversityKingstonOntarioCanada K7L 3N6

Aims In this study,we examined the extent to which between-species leaf size var.ation r.lates to var.ation in the intensity of leaf pr.duction in her.aceous *** size var.ation has been most commonly inter.r.ted in ter.s of biomechanical constr.ints(*** by plant size limitations)or.in ter.s of dir.ct adaptation associated with leaf size effects in optimizing impor.ant physiological functions of individual leaves along envir.nmental gr.dients(*** temper.tur. and moistur.).An additional inter.r.tation is explor.d her.,wher. adaptation may be mor. dir.ctly associated with the number.of leaves pr.duced and wher. r.latively small leaf size then r.sults as a tr.de-off of high‘leafing intensity’—*** of leaves pr.duced per.unit plant body *** The r.lationships between mean individual leaf mass,number.of leaves and plant body size wer. examined for.127 species of her.aceous angiosper.s collected fr.m natur.l populations in souther. Ontar.o,*** Findings In all,88%of the var.ation in mean individual leaf mass acr.ss species,spanning four.or.er. of magnitude,is accounted for.by a negative isometr.c(pr.por.ional)tr.de-off r.lationship with leafing *** r.sults par.llel those r.por.ed in r.cent studies of woody *** each leaf is nor.ally associated with an axillar. bud or.mer.stem,having a high leafing intensity is equivalent to having a gr.ater.number.of mer.stems per.unit body size—i.e.a lar.er.bud bank’.Accor.ing to the‘leafing intensity pr.mium’hypothesis,because an axillar. mer.stem r.pr.sents the potential to pr.duce either.a new shoot or.a r.pr.ductive str.ctur.,high leafing intensity should confer.gr.ater.ar.hitectur.l and/or.r.pr.ductive plasticity(with r.latively small leaf size r.quir.d as a tr.de-off).This gr.ater.plasticity,we suggest,should be especially impor.ant for.smaller.species since they ar. likely to suffer.gr.ater.suppr.ssion of gr.wth and r.pr.duction fr.m competition within

关键词： bud bank leafing intensity mer.stems plant size plasticity r.pr.ductive economy

The r.lationship between individual seed quality and mater.al plant body size in cr.wded her.aceous vegetation

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Jour.al of Plant Ecology 2014年第4期7卷 330-336页

作者： Tomo Nishizawa lonnie W.Aar.sen Depar.ment of Biology Queen’s UniversityKingstonOntario K7L 3N6Canada

Aims In most natur.l plant populations,ther. is a str.ng r.ght-skewed dis-tr.bution of body sizes for.r.pr.ductive *** vast major.ty ar. r.latively small,suppr.ssed weaklings that manage not just to sur.ive effects of cr.wding/competition and other.hazar.s but also to pr.duce *** r.sear.h has shown that because of their.r.latively lar.e number.,these r.latively small r.sident plants collectively contr.bute most of the seed offspr.ng pr.duction available for.the population in the next ***,the success of these offspr.ng will depend in par. on their.quality,*** by seed size and r.sour.e ***,in the pr.sent study,we used mater.al fr.m natur.l populations of her.aceous species to test the null hypothesis that ther. is no significant r.lationship between body size var.ation in r.sident plants-r.sulting fr.m between-site var.ation in the intensity of cr.wding/competition-and var.ation in the mass or.N content of their.individual *** using populations of 56 her.aceous species common in easter. ontar.o,total above-gr.und dr. plant mass,mean mass per.seed and mean nitr.gen(N)content per.seed wer. r.cor.ed for.a sample of the lar.est r.sident plants and also for.the smallest r.pr.duc-tive plants gr.wing in local neighbour.oods with the most sever. cr.wding/competition fr.m near.*** Findingsmass per.seed was numer.cally smaller.fr.m the smallest r.sident plants for.most study species,but with few exceptions,this was not significantly differ.nt(P>0.05)fr.m mass per.seed fr.m the lar.-est r.sident *** r.sults ther.for. showed no gener.l effect of mater.al plant body size on individual seed mass,or.N *** suggests that the r.pr.ductive output of the smaller.half of the r.sident plant size distr.bution within these populations is likely to contr.bute not just most of the seed pr.duction available for.the next gener.tion but also seed offspr.ng that ar. just as likely-on a per.i

关键词： cr.wding competition plant size r.pr.ductive economy seed mass seed N content

Big plants--do they limit species coexistence?

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Jour.al of Plant Ecology 2009年第3期2卷 119-124页

作者： Laur. M.Keating lonnie W.Aar.sen Depar.ment of Biology Queen’s UniversityKingstonOntarioCanada K7L 3N6

Aims Accor.ing to conventional theor.,lar.er.plant species ar. likely to inflict mor. intense competition on other.smaller.*** tested a deducible pr.diction fr.m this:that a lar.er.species should gener.lly be expected to impose gr.ater.limits on the number.of species that can coexist with *** Species r.chness was sampled under.plant canopies for.a selection of woody species(‘host’species)that display a wide r.nge of adult sizes(fr.m small shr.bs to lar.e tr.es),gr.wing within natur.l vegetation of the Inter.or.Douglas-fir.zone of souther. Br.tish Columbia,*** data wer. compar.d with species r.chness levels sampled within r.ndomly placed plots within the host species *** Findings A pr.minent host species size effect on species r.chness was detected but only nar.owly at the small end of the species size *** most(90%)of the incr.asing size r.nge of host species,the number.of species r.siding under.the host canopy showed no significant decr.ase r.lative to the number.expected by r.ndom assembly,based on species r.chness within r.ndomly defined equivalent ar.as within the habitat of the host *** appar.nt‘null effect’,we suggest,is explained not because these lar.er.species have no effect on community *** postulate that lar.er.species ar. indeed likely to be mor. effective in causing competitive exclusion of some smaller.species(as expected fr.m conventional theor.),but that any potential limitation effect of this on r.sident species r.chness is offset for.two r.asons:(i)lar.er.species also gener.te niche spaces that they cannot exploit under.their.own canopies and so have minimal impact(as competitor.)on smaller.species that can occupy these niches and(ii)cer.ain other.small species—despite small size—have effective competitive abilities under.the sever. competition that occur. within host neighbour.oods of lar.er.*** and other.r.cent studies call for.r.-evaluation of tr.ditional views on the r.le o

关键词： competition competitive exclusion plant size physical space niche r.ndom assembly r.pr.ductive economy

Leaf size ver.us leaf number.r.deoffs in dioecious angiosper.s

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Jour.al of Plant Ecology 2013年第1期6卷 29-35页

作者： Stephanie L.Scott lonnie W.Aar.sen Depar.ment of Biology Queen’s UniversityKingstonOntarioCanada K7L 3N6

Aims We explor. the possible r.le of leaf size/number.tr.de-offs for.the inter.r.tation of leaf size dimor.hism in dioecious plant *** Total above-gr.und biomass(both male and female)for.thr.e her.aceous dioecious species and individual shoots(fr.m both male and female plants)for.thr.e woody dioecious species wer. sampled to r.cor. individual leaf dr. mass,number.of leaves,dr. mass of r.sidual above-gr.und tissue(all r.maining non-leaf biomass),number.of flower./inflor.scences(for.her.aceous species)and number.of *** Findings For.two out of thr.e woody species and two out of thr.e her.aceous species examined,male plants pr.duced smaller.leaves but with higher.leafing intensity—*** leaves per.unit of suppor.ing(r.sidual)shoot tissue or.plant body mass—compar.d with *** and female plants,however.did not differ.in shoot or.plant body mass or.br.nching *** inter.r.t these r.sults as possible evidence for.a dimor.hic leaf deployment str.tegy that pr.motes both male and female function,*** male plants,capacity as a pollen donor.may be favor.d by selection for.a br.adly spaced flor.l display,hence favor.ng r.latively high leafing intensity because this pr.vides mor. numer.us axillar. mer.stems that can be deployed for.flower.ng,thus r.quir.ng a r.latively small leaf as a *** one her.aceous species,higher.leafing intensity in males was associated with gr.ater.flower.pr.duction than in *** contr.st,in female plants,selection favor. a r.latively lar.e leaf,we pr.pose,because this pr.motes gr.ater.capacity for.localized photosynthate pr.duction,thus suppor.ing the locally high ener.etic cost of axillar. fr.it and seed development,which in tur. r.quir.s a r.latively low leafing intensity as a tr.de-off.

关键词： bud bank leaf dimor.hism leafing intensity dioecy

Competition and body size in plants:the between-species tr.deoff for.maximum potential ver.us minimum r.pr.ductive thr.shold size

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Jour.al of Plant Ecology 2011年第3期4卷 115-122页

作者： Amanda J.Tr.cey lonnie W.Aar.sen Depar.ment of Biology Queen’s UniversityKingstonON K7L 3N6Canada

Aims Accor.ing to tr.ditional theor.,super.or.competitive ability in plants gener.lly r.quir.s r.latively lar.e plant body *** even within the most cr.wded vegetation,most r.sident species ar. r.latively small;species size distr.butions ar. r.ght-skewed at vir.ually ever. *** examine a potential explanation for.this par.dox:small species coexist with and outnumber.lar.e species because they have gr.ater.r.pr.ductive economy’,*** ar. better.equipped—and hence mor. likely—to pr.duce offspr.ng despite sever. size suppr.ssion fr.m intense *** r.ndomly placed plots within old-field vegetation wer. sur.eyed acr.ss the gr.wing *** each plot,the lar.est(MAX)and smallest(MIN)r.pr.ductive individuals of each r.sident species wer. collected for.above-gr.und dr. mass *** tested thr.e hypotheses:(i)smaller.r.sident species(with smaller.MAX size)have gener.lly smaller.r.pr.ductive thr.shold sizes;(ii)smaller.r.sident species have gr.ater.r.pr.ductive economy’,i.e.a smaller.MIN r.lative to MAX r.pr.ductive plant size;and(iii)MIN size pr.dicts plot occupancy(species abundance within the community)better.than MAX *** Findings The r.sults suppor.ed the fir.t and thir.,but not the second ***,we could not r.ject the hypothesis that smaller.species have gr.ater.r.pr.ductive economy,as it was not possible to r.cor. data for.the lar.est potential plant size for.each species—since even the lar.est(MAX)plants collected fr.m our.sampled plots wer. subjected to competition fr.m neighbour. under.these natur.l field ***,contr.r. to conventional competition theor.,mor. successful species(in ter.s of gr.ater.plot occupancy)had smaller.minimum not lar.er.or.smaller.maximum r.pr.ductive *** r.sults suggest that a small r.pr.ductive thr.shold size,commonly associated with r.latively small potential body size,is gener.lly mor. effective in tr.nsmitting genes into futur. gener.tions when selection

关键词： competition coexistence fitness old-field d r.pr.ductive economy species size distr.bution

No evidence demonstr.ting hepatotoxicity associated with hydr.xycitr.c acid

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Wor.d Jour.al of Gastr.enter.logy 2009年第32期15卷 4087-4089页

作者： Sidney J Stohs Har.y G Pr.uss Sunny E Ohia Gilber. r.Kaats Car. L Keen lonnie D Williams Geor.e A Bur.ock School of Phar.acy and Health Pr.fessions Creighton University Medical Center4967 Stillwater TrailFriscoTX 75034United States

Although a number.of cases of hepatotoxicity ar. associated with the use of Hydr.xycut weight management pr.ducts, it has been alleged that their.effects ar. pr.mar.ly due to the pr.sence of hydr.xycitr.c acid (HCA, as Super.Citr.Max) in the for.ulations. However. while these pr.ducts contain up to 20 differ.nt ingr.dients, some do not contain HCA. Case studies r.por.ed to date have not consider.d in depth the liter.tur. on the numer.us animal and human studies that have been conducted on the safety and effi cacy of HCA. No HCA-associated hepatotoxicity or.tr.atment-r.lated adver.e effects have been r.por.ed in these studies, and thus it is pr.matur. to make the assumptions pr.sented in the r.cent case studies r.gar.ing Hydr.xycut. If it is established in well contr.lled studies that the use of these for.ulations with and/or.without HCA can r.sult in the occur.ence or.pr.gr.ssion of hepatotoxicity, additional studies should be conducted to char.cter.ze the causative factor.s).

关键词： Hydr.xycitr.c acid Super.Citr.Max Hydr.xycitr.c acid-SX Gar.inia cambogia Hydr.xycut Liver.failur. Hepatotoxicity Safety and efficacy