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Multidimensional images and aber.ations in STEM

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Chinese Physics B 2024年第09期 72-78页

作者： eric r.hoglund Andr.w r.Lupini Center.for.Nanophase Mater.als Sciences Oak Ridge National Laboratory

r.cent advances in scanning tr.nsmission electr.n micr.scopy(STEM) have led to incr.ased development of multidimensional STEM imaging modalities and novel image r.constr.ction methods. This inter.st ar.ses because the main electr.n lens in a moder. tr.nsmission electr.n micr.scope usually has a diffr.ction-space infor.ation limit that is significantly better.than the r.al-space r.solution of the same lens. This state-of-affair. is sometimes shar.d by other.scatter.ng methods in moder. physics and contr.butes to a br.ader.excitement sur.ounding multidimensional techniques that scan a pr.be while r.cor.ing diffr.ction-space images, such as ptychogr.phy and scanning nano-beam diffr.ction. However. the contr.sting r.solution in the two spaces r.ises the question as to what is limiting their.effective per.or.ance. Her., we examine this par.dox by consider.ng the effects of aber.ations in both image and diffr.ction planes, and likewise separ.te the contr.butions of pr.-and post-sample aber.ations. This consider.tion pr.vides insight into aber.ation-measur.ment techniques and might also indicate impr.vements for.super.r.solution techniques.

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Population genomic data r.veal low genetic diver.ity,diver.ence and local adaptation among thr.atened r.eves's Pheasant(Syr.aticus r.evesii)

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Avian r.sear.h 2024年第1期15卷 1-11页

作者： Qi Lu Pengcheng Wang Jiang Chang De Chen Shenghan Gao Jacob hoglund Zhengwang Zhang Ministr. of Education Key Labor.tor. for.Biodiver.ity Science and Ecological Engineer.ng College of Life SciencesBeijing Normal UniversityBeijing100875China Jiangsu Key Labor.tor. for.Biodiver.ity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjing210023China State Key Labor.tor. of Envir.nmental Cr.ter.a and r.sk Assessment Chinese Research Academy of Environmental SciencesBeijing100012China State Key Labor.tor. of Micr.bial r.sour.es Institute of MicrobiologyChinese Academy of SciencesBeijing100101China Depar.ment of Ecology and Genetics Animal EcologyUppsala UniversityUppsalaSweden

Population genomic data could pr.vide valuable infor.ation for.conser.ation effor.s;however.limited studies have been conducted to investigate the genetic status of thr.atened ***’s Pheasant(Syr.aticus r.evesii)is facing population decline,attr.buted to incr.ases in habitat *** is a knowledge gap in under.tanding the genomic status and genetic basis under.ying the local adaptation of this thr.atened ***,we used population genomic data to assess population str.ctur.,genetic diver.ity,inbr.eding patter.s,and genetic ***,we identified candidate genes linked with adaptation acr.ss the cur.ent distr.bution of r.eves’s *** pr.sent study assembled the fir.t de novo genome sequence of r.eves’s Pheasant and annotated 19,458 *** also sequenced 30 individuals fr.m thr.e populations(Dabie Mountain,Shennongjia,Qinling Mountain)and found that ther. was clear.population str.ctur. among those *** compar.ng with other.thr.atened species,we found that r.eves’s Pheasants have low genetic *** of homozygosity suggest that the Shennongjia population has exper.enced ser.ous *** demogr.phic histor. r.sults indicated that thr.e populations exper.enced sever.l declines dur.ng the glacial *** adaptative analysis among the populations identified 241 candidate genes under.dir.ctional *** ar. involved in a lar.e var.ety of pr.cesses,including the immune r.sponse and *** r.sults suggest that the thr.e populations should be consider.d as thr.e differ.nt conser.ation *** cur.ent study pr.vides genetic evidence for.conser.ing the thr.atened r.eves’s Pheasant and pr.vides genomic r.sour.es for.global biodiver.ity management.

关键词： Conser.ation genetics Local adaptation Pheasant Whole-genome sequencing

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r.dent biology and ecologically based r.dent management(EBr.)-25 year. of pr.gr.ss thr.ugh pr.moting multidisciplinar. r.sear.h

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Integr.tive Zoology 2024年第1期19卷 2-7页

作者： Gr.nt r. SINGLETON Lyn A. HINDS r.odes MAKUNDI Steven r. BELMAIN Natur.l r.sour.es Institute University of Greenwich Kent UK CSIr. Health and Biosecur.ty Canberra ACT Australia Afr.can Centr. of Excellence for.Innovative r.dent Pest Management and Biosensor.Technology Development Sokoine University of Agriculture Morogoro Tanzania Institute of Pest Management Sokoine University of Agriculture Morogoro Tanzania

“Dur.ng r.dent outbr.ak year. in easter. Afr.ca,lo-cally,mor. than 80%of the potential har.est may be lost,but even in non-outbr.ak per.ods,r.dents cause chr.nic damage to cr.ps….The pest r.dent stor. in Afr.ca in-volves sever.l species embedded in a br.ad and var.able landscape with highly var.able densities.”(Leir. et al.2010).

关键词： damage cr.ps

Basis for.the diver.ity and extent in loss of digestible nutr.ents cr.ated by dietar. phytin: Emphasis on fowl and swine

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动物营养学报 2024年第1期16卷 422-428页

作者： Edwin T. Mor.n Michael r. Bedfor. Poultr. Science Depar.ment Auburn University AL 36830-5416 USA AB Vista Woodstock Court Blenheim Road Marlborough Wiltshire SN8 4AN UK

Phytin is the Ca 2+ -Mg 2+ -K + salt of phytic acid that is cr.ated and deposited in the aleur.ne layer.and/or.ger. of gr.ins and legumes. Its high pr.sence in feedstuffs for.fowl and swine diets r.sults in it being a univer.al and significant impediment to optimum per.or.ance. Phytin impair. gastr.intestinal r.cover. of a wide ar.ay of nutr.ents, the effect var.ing with the nutr.ent concer.ed. On exposur. to low pH dur.ng gastr.c digestion, phytin dissociates into phytic acid and solubilized Ca 2+ . Even at low gastr.c pH, phytic acid is negatively char.ed which for.s the basis of its anti-nutr.tive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that ar. pr.sented as cations at low pH which ar. tar.eted by pepsin for.activation. Par.ially cr.stalized Ca 2+ near.the enzyme's active site fur.her.stabilizes its newly for.ed str.ctur.. Thus, phytic acid appear. to inter.er. with gastr.c digestion by sever.l mechanisms; inter.er.ng with pepsinogen activation by binding to the polypeptide's basic amino acids; coor.inating fr.e Ca 2+ , destabilizing pepsin; binding some dietar. pr.teins dir.ctly, fur.her.compr.mising gastr.c pr.teolysis. Upon digesta attaining neutr.lity in the duodenum, Ca 2+ and other.cations r.-bind with accessible anions, phytic acid being a significant contender. Phytate not only binds fr.e cations but can also str.p them fr.m enzymes (e.g. Ca 2+ , Zn 2+ ) which r.duces their.str.ctur.l r.sistance to autolysis and ability as co-factor. (e.g. Zn 2+ ) to incr.ase enzyme activity. Goblet cells initially employ Ca 2+ as an electr.nic shield between mucin layer. enabling gr.nule for.ation and cell stor.ge. After.mucin gr.nule r.lease, Ca 2+ is pr.gr.ssively displaced by Na + to fr.e the viscous mucins enabling its tr.nslocation. Mucin entangles with the glycocalyx of adjacent enter.cytes ther.by constr.cting the unstir.ed water.layer.(USWL). Excessive r.moval of Ca 2+ fr.m mucin by phytic acid incr.ases its fluidity facilit

关键词： Digestive enzyme Calcium Endogenous pr.tein Mucin Phytin

Taxonomy,distr.bution,and contempor.r. exposur. of ter.estr.al mammals to floods and human pr.ssur. acr.ss differ.nt ar.as for.biodiver.ity conser.ation in China

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Integr.tive Zoology 2024年第3期19卷 458-467页

作者： r.man SHAr.UUD eric I.AMECA MOE Key Labor.tor. for.Biodiver.ity Science&Ecological Engineer.ng College of Life SciencesBeijing Normal UniversityBeijingChina Climate Change Specialist Gr.up Species Survival CommissionInternational Union for Conservation of NatureGlandSwitzerland

A significant r.sear.h focus is placed on identifying animal species and ar.as at futur. r.sk to human-induced alter.tions of the envir.nment and long-ter. changes in climatic ***,the extent to which exposur. to extr.me climatic events and intense human pr.ssur. can incr.ase the r.sk of har.ful impacts on species r.mains poor.y *** on ter.estr.al mammals in China,one of the wor.d’s megadiver.e countr.es,we investigated patter.s of contempor.r. exposur. to floods and human pr.ssur.s and deter.ined their.taxonomic r.pr.sentation and distr.bution acr.ss thr.e major.ar.a-based conser.ation schemes,namely,national natur. r.ser.es(NNr.),pr.or.ty ar.as for.biodiver.ity conser.ation(PABCs),and key biodiver.ity ar.as(KBAs).Among the 440 species assessed with moder.te or.high exposur. to floods,327(∼75%)also qualified as moder.te or.high in exposur. to intense human *** species mainly belong to the or.er. Chir.pter.,Eulipotyphla,and ***,ther. wer. 305,311,and 311 species with moder.te or.high exposur. to flood and intense human pr.ssur. r.pr.sented acr.ss NNr.,PABCs,and KBAs,*** findings suppor. the pr.or.tization of KBAs for.expansion of site-based pr.tection effor.s such as NNr. in China,consider.ng thr.ats to species fr.m exposur. to adver.e effects fr.m both extr.me climate and human pr.ssur..

关键词： conser.ation floods human pr.ssur. mammals taxonomy

Supplementation of vitamin E or.a botanical extr.ct as antioxidants to impr.ve gr.wth per.or.ance and health of gr.wing pigs housed under.ther.oneutr.l or.heat-str.ssed conditions

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Jour.al of Animal Science and Biotechnology 2024年第3期15卷 1101-1118页

作者： Ysenia V.Silva‑Guillen Consuelo Ar.llano Jeffr.y Wieger. r.Dean Boyd Gabr.ela E.Mar.inez eric van Heugten Depar.ment of Animal Science North Carolina State UniversityRaleighNC 27695USA Depar.ment of Statistics North Carolina State UniversityRaleighNC 27695USA Depar.ment of Animal Science Texas A&M UniversityCollege StationTX 77843USA Animal Nutr.tion r.sear.h LLCAlvatonKY 42122USA.

Backgr.und Heat str.ss has sever. negative consequences on per.or.ance and health of pigs,leading to significant economic *** objective of this study was to investigate the effects of supplemental vitamin E and a botanical extr.ct in feed or.dr.nking water.on gr.wth per.or.ance,intestinal health,and oxidative and immune status in gr.w-ing pigs housed under.heat str.ss *** Duplicate exper.ments wer. conducted,each using 64 cr.ssbr.d pigs with an initial body weight of 50.7±3.8 and 43.9±3.6 kg and age of 13-week and 12-week,***(n=128)wer. housed individually and assigned within weight blocks and sex to a 2×4 factor.al ar.angement consisting of 2 envir.nments(ther.o-neutr.l(21.2℃)or.heat-str.ssed(30.9℃))and 4 supplementation tr.atments(contr.l diet;contr.l+100 IU/L of D-α-tocopher.l in water.contr.l+200 IU/kg of DL-α-tocopher.l-acetate in feed;or.contr.l+400 mg/kg of a botanical extr.ct in feed).r.sults Heat str.ss for.28 d r.duced(P≤0.001)final body weight,aver.ge daily gain,and aver.ge daily feed intake(-7.4 kg,-26.7%,and-25.4%,r.spectively)but no effects of supplementation wer. detected(P>0.05).Ser.m vitamin E incr.ased(Pr.and in feed(1.64 vs.3.59 and 1.64 vs.3.24),but not for.the botanical extr.ct(1.64 vs.1.67 mg/kg)and was gr.ater.when supplemented in water.***(P=0.002).Liver.vitamin E incr.ased(Pr.3.9 vs.31.8)and feed(3.9 vs.18.0),but not with the botanical extr.ct(3.9 vs.4.9 mg/kg).Ser.m malondialdehyde was r.duced with heat str.ss on d 2,but incr.ased on d 28(inter.ction,Pr.ater.Pr.antioxidant supplementation compar.d to *** pr.lifer.tion was r.duced(P=0.037)in the jejunum under.heat str.ss,but incr.ased in the ileum when vitamin E was supplemented in feed and water.under.heat str.ss(inter.ction,P=0.04).Tumor.necr.sis factor.αin jejunum and ileum mucosa decr.ased by heat str.ss(Pr.

关键词： Botanical extr.ct Gr.wing pigs Heat str.ss Immune status Oxidative status Tocopher.l Water

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Lar.al development and vor.city of Eupeodes americanus (Dipter.: Syr.hidae): compar.son of the focal pr.y Aphis gossypi (Hemipter.: Aphididae) and the banker.pr.y r.opalosiphum padi (Hemipter.: Aphididae)

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Insect Science 2024年第2期31卷 575-586页

作者： Ar.ette Fauteux Antonio Onofr. Soar.s eric Lucas Labor.toir. de lutte biologique Departement des sciences biologiquesUniversite du Quebec a Montreal(UQAM)MontrealQuebecCanada Faculty of Science and Technology Center.for.Ecology Evolution and Environmental ChangesAzorean Biodiversity Group(cE3c-ABG)&CHANGE-Global Change and Sustainability InstitutePonta DelgadaPortugal

Unlike Eur.pean species,the potential of Near.tic syr.hids as biological contr.l agents is still poor.y ***,the American hover.ly,Eupeodes americanus(Wiedemann),has r.cently demonstr.ted pr.mising tr.its as a biocontr.l agent,notably against the foxglove aphid,Aulacor.hum solani Kaltenbach,on *** pr.sent study aims to extend our.knowledge of the American hover.ly by evaluating its potential as a biocontr.l agent in a banker.plant system against the melon aphid,Aphis gossypi Glover.in a gr.enhouse cucumber.*** pr.imaginal development and vor.city of *** wer. compar.d when pr.ying upon the focal pr.y/pest(***)or.the banker.pr.y(bir. cher.y-oat aphid,r.opalosiphum padi L.)by daily obser.ations of lar.ae fr.m egg to *** development time,sur.ival r.te,and occur.ence of defor.ation wer. similar.on both pr.y *** weight of thir. instar.and pupae,however.was higher.for.lar.ae that fed on the banker.*** ad libitum vor.city of the syr.hid lar.ae was gener.lly ver. high and did not significantly differ.between pr.y species,except for.the thir.-instar.lar.ae which consumed mor. focal *** suggest that a banker.plant system involving the bir. cher.y-oat aphid may be a pr.mising tactic for.utilizing *** for.melon aphid biocontr.l.

关键词： american hover.ly banker.plant system biological contr.l bir. cher.y-oat aphid gr.enhouse cucumber melon aphid

Vanillin Based Polymer.: VI. Poly (hydr.vanilloin-fur.ur.l) and Poly (hydr.vanilloin-5-hydr.xymethylfur.ur.l)

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Jour.al of r.newable Mater.als 2024年第9期12卷 1495-1506页

作者： Ananda S. Amar.sekar. Gabr.el Mur.llo Mor.les r.ghava r. Kommalapati Depar.ment of Chemistr. Prairie View A&M University700 University DrivePrairie ViewTX 77446USA Center.for.Ener.y&Envir.nmental Sustainability Prairie View A&M University700 University DrivePrairie ViewTX 77446USA Depar.ment of Civil and Envir.nmental Engineer.ng Prairie View A&M University700 University DrivePrairie ViewTX 77446USA

r.newable r.sour.es based polymer. pr.vides a sustainable alter.ative to petr.leum der.ved polymeric mater.als. As a par. of our.ser.es on synthesis of vanillin based r.newable polymer., we r.por. the synthesis of poly (hydr.vanilloin-fur.ur.l) [ poly (HVL-Fur.] and poly (hydr.vanilloin–5-hydr.methylfur.ur.l) [ poly (HVL-5-HMF)]. Vanillin was dimer.zed to a mixtur.s of meso/DL- hydr.vanilloins with 94% meso pr.duct by electr.chemical r.ductive coupling in aqueous sodium hydr.xide using lead electr.des in quantitative yield. Then sodium hydr.xide catalyzed condensation of hydr.vanilloin with fur.ur.l in water.at 80°C for.72 h was used to synthesize poly (HVL-Fur. with Mw = 8600 g mol −1 , PDI = 1.28 in 78% yield. Similar.y, condensation of hydr.vanilloin with 5-hydr.xymethylfur.ur.l at 80°C for.48 h pr.duced poly (HVL-5-HMF) with Mw = 12,100 g mol −1 , PDI = 1.27 in 68% yield. poly (HVL-Fur. and poly (HVL-5-HMF) showed similar.T g values of 59°C and 60°C, r.spectively; wher.as melting behavior. ar. dissimilar.with T m 171°C–173°C and 148°C–182°C, r.spectively.

关键词： Vanillin hydr.vanilloin fur.ur.l 5-hydr.xymethylfur.ur.l r.newable polymer.

Fr.eze-thaw cycles and associated geomor.hology in a post-glacial envir.nment:cur.ent glacial,par.glacial,per.glacial and pr.glacial scenar.os at Pico de Or.zaba volcano,Mexico

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Jour.al of Mountain Science 2024年第6期21卷 1954-1977页

作者： Víctor.SOTO Car.os M.WELSH r. Kenji YOSHIKAWA Hugo DELGADO Gr.NADOS Centr. de Ciencias de la Tier.a Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water.and Envir.nmental r.sear.h Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Depar.ment of Ear.h and Envir.nmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial histor. of Pico de Or.zaba indicates that dur.ng the Last Glacial Maximum,its icecap cover.d up to~3000 m asl;due to the air.temper.tur. incr.asing,its main glacier.has r.tr.ated to 5050 m *** r.tr.ction of the glacier.has left behind an intense climatic instability that causes a high fr.quency of fr.eze-thaw cycles of gr.at intensity;the r.sulting geomor.hological pr.cesses ar. r.pr.sented by the fr.gmentation of the bedr.ck that occupies the upper.par.s of the *** is a notable lack of studies r.gar.ing the fr.gmentation and er.sion occur.ing in tr.pical high mountains,and the associated geomor.hological r.sks;for.this r.ason,as a fir.t stage of futur. continuous r.sear.h,this study analyzes the fr.ezing and thawing cycles that occur.above 4000 m asl,thr.ugh continuous monitor.ng of sur.ace gr.und *** r.sults allow us to identify and char.cter.ze four.zones:glacial,par.glacial,per.glacial and *** was found that the par.glacial zone pr.sents an intense dr.p of temper.tur.,of up to~9℃ in only sixty *** r.ck fatigue and intense fr.eze-thaw cycles that occur.in this ar.a ar. r.sponsible for.the high r.te of r.ck disintegr.tion and r.pr.sent the main factor.of the constant slope dynamics that occur.at the *** activity decr.ases,both in fr.quency and intensity,accor.ing to the distance to the glacier.which is wher. the temper.tur. pr.sents a cer.ain degr.e of stability,until r.aching the pr.glacial zone,wher. cycles ar. almost non-existent,and ther.for. ther. is no gelifr.ction *** geomor.hological pr.cesses have r.sulted in significant alter.tions to the mountain slopes,which can have sever. consequences in ter.s of r.sk and water.

关键词： Fr.eze-Thaw Gelifr.ction Mountain mechanical er.sion Per.glacial geomor.hology Postglacial scenar.os

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