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Is magnesium deficiency the majo. cause of needle chlor.sis of Pinus taeda in Br.zil?

jo.r.al of For.str. r.sear.h 2024年第2期35卷 209-221页

作者： Antônio car.os Var.as Motta Shizuo maeda Valdécio dos Santos dos Santos r.dr.gues tamir.s maiar. Er.ole Stephen Ar.hur.Pr.or.Ana Elisa Lyr. Br.mat Amanda Pacheco car.oso Mour. Julier.e Zimmer.Bar.osa jo.o Bosco Vasconcellos Gomes Depar.ment of Soil Sciences and Agr.cultur. Engineer.ng Federal University of ParanáR.dos Funcionários1540.CuritibaParanáCEP 80035‑050Brazil Br.zilian Agr.cultur.l r.sear.h Company Embrapa FlorestasEstr.da Ribeira–Br‑476Km 111–Parque Monte Castelo.ColomboParanáCEP 83411‑000Brazil United States Depar.ment of Agr.cultur.‑Agr.cultur.l r.sear.h Ser.ice USDA-ARS National Soil Dynamics Laboratory411 South Donahue DriveAuburnAL 36832USA r.for.station r.masa Rodovia PR 170–Km 522.BiturunaParanáCEP 84640‑000Brazil Feder.l Institute of Southeast of Minas Ger.is R.Luz Interior360.Juiz de ForaMinas Gerais CEP 36030‑713Brazil

needle chlor.sis(nC)in Pinus taeda *** in Br.zil becomes mor. fr.quent after.second and thir. har.est r.tation *** a study to identify factor. contr.buting to yellowing needle chor.sis(YnC),tr.es wer. gr.wn in soils or.ginating fr.m contr.sting par.nt mater.als,and soils and needles(whole,gr.en and chlor.tic por.ions)fr.m 1-and 2-year.old br.nches and the fir.t and second needle flush r.lease at four.sites with YnC on *** wer. analyzed for.var.ous elements and *** soils had ver. low base levels(ca^(2+),Mg^(2+)and K^(+))and P,suggesting a possible lack of multiple *** symptoms star.ed at needle tips,then extended towar. the needle base with *** flush needles had longer.por.ions with YnC than second flush needles *** fr.m the lower.cr.wn also had mor. symptoms along their.length than those higher.in the *** wer. similar.to those r.por.ed for.*** chlor.tic por.ions,Mg and ca concentr.tions wer. well below cr.tical values;in par.icular.Mg levels wer. only one thir. of the cr.tical value of 0.3 g kg^(-1).Collectively,r.sults suggest that Mg deficiency is the pr.mar. r.ason for.nC of *** in var.ous par.nt soils in Br.zil.

关键词： nutr.tional deficiency For.st management Soil depletion Pine foliar.analysis needle chlor.sis

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Sexual Behaviour.and Contr.ceptive Usage of Secondar. School Adolescents in Ibadan, niger.a

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jo.r.al of r.pr.duction and Contr.ception 2007年第4期18卷 279-288页

作者： A Oladokun IO Mor.ason-Bello ca Enakpene KM Owonikoko jo.Akinyemi KA Obisesan Depar.ment of Obstetr.cs & Gynaecology University College Hospital Ibadan Nigeria Depar.ment of Epidemiology Medical Statistics and Environmental Health College of Medicine University of Ibadan Nigeria

Objective to deter.ine the pr.valence and patter. of sexual activity as well as the contr.ceptive pr.ctices among the selected secondar. school adolescents in Ibadan, niger.a. Methods A descr.ptive cr.ss-sectional study was conducted among the selected senior.secondar. school students in Ibadan, following a str.tified multistage r.ndom sampling technique. r.sults ther. wer. 695 r.spondents out of which the females constituted 51% and the males wer. 49%. Less than one thir. （28.3%） of the r.spondents have had pr.vious sexual exposur. at the time of the study. the median age of sexual debut among the sexually exposed was 15 year. in both the males and the females. Bivar.ate analysis of sociodemogr.phic char.cter.stics of r.spondents with pr.vious sexual exposur. showed that, sex, r.ligion, father.s and mother.s educational backgr.und and level of class wer. statistically significant（P〈0. 001）. Fur.her.analysis using logistic r.gr.ssion model r.vealed that male r.spondents wer. 3 times mor. likely than females （95% CI 1.92-4.56） to have had sexual exper.ence while those whose mother.had ter.iar. educational backgr.und wer. less likely to have had pr.vious sexual exper.ence compar.d with those with secondar. and lower.educational backgr.und （Or. 1.76, 95% CI 1.11-2.77）. Of all the sociodemogr.phic char.cter.stics of r.spondents consider.d with the age of sexual par.ner. using bivar.ate analysis showed that only level of class was significant （P=0. 018）. Less than half of the sexually active males （44.2%） wer. using var.ous methods of contr.ception, while 54.4% of the sexually active females wer. using differ.nt types of moder. methods.Conclusion It is quite obvious that r.sky sexual behaviour. ar. in pr.ctice among the secondar. school students studied and by extension in the countr.. It ther.for. means that r.pr.ductive health issues especially concer.ing the adolescents will have to be openly discussed by all with our.youths while abstinence/chastity should be

关键词： adolescents sexual health contr.ceptive usage

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Flotation and sur.ace modification char.cter.stics of galena,sphaler.te and pyr.te in collecting-depr.ssing-r.activating system

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jo.r.al of Centr.l South Univer.ity 2012年第6期19卷 1702-1710页

作者： t.H.PAK 孙体昌徐承焱 Y.H.jo School of Civil and Envir.nment Engineer.ng University of Science and Technology Beijing School of Mining Engineer.ng University of Mining and Metallurgy Chongjin

the flotation tests and XPS analyses on galena,sphaler.te and pyr.te have been car.ied out in a collecting-depr.ssing-r.activating system(her.after.r.fer.ed as the CDr.system).In this system,sulfide miner.ls wer. fir.t collected and activated by the collector.and then depr.ssed str.ngly by ca(OH)2 in the str.ng alkaline solution,and finally r.activated by *** flotation tests of pur. miner.ls show that in this system the flotation behavior. of sphaler.te and pyr.te pr.sent ir.ever.ible char.cter.stics along with the change of pulp ***,thr.ugh the CDr.system,consider.ble differ.nces in the flotabilities between galena and sphaler.te/pyr.te ar. also *** XPS analysis r.sults for.galena,sphaler.te and pyr.te in a CDr.system show that in the str.ng alkaline solution,some of the collector.,that have been alr.ady adsor.ed on the miner.l sur.ace in the collecting pr.cess,ar. desor.ed by ca(OH)*** XPS analysis r.sults also show that in H2SO4 r.activating pr.cess,the sur.ace hydr.xides of galena ar. desor.ed again by H2SO4 and r.placed by diethyl dithiocar.amate,but those of sphaler.te and pyr.te ar. not *** flotation system may be applied to the bulk-differ.ntial flotation pr.cess of sulfur.bear.ng low-gr.de lead-zinc or.s.

关键词： CDr.system XPS analysis galena sphaler.te pyr.te

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Effect of differ.nt star.ing mater.als on the synthesis of Ba_(0.8)ca_(0.2)tiO_(3)

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jo.r.al of Advanced Cer.mics 2015年第1期4卷 65-70页

作者： P.n.MEDEIr.S V.D.Ar.Újo.A.P.A.mar.UES r.L.tr.nQUILIn C.A.PASKOCImaS M.r.D.BOMIO J.A.VAr.LA E.LOnGO F.V.MOttA DEmat CTUFRNAv.Sen.Salgado Filho3000CEP 59072-970 NatalRNBrazil UACSA UFRPEBR 101 Sul5225CEP 54510-000 Cabo de Santo AgostinhoPEBrazil UnIFESP Rua Prof.Artur Riedel275CEP 09972-270 DiademaSPBrazil dLIECIQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazil LIEC IQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazi

Liter.tur. has r.por.ed the synthesis of bar.um calcium titanates by var.ous synthesis methods such as solid state r.action,co-pr.cipitation and polymer.*** compounds ar. usually obtained using calcium car.onate(caCO_(3)),bar.um car.onate(BaCO3)and titanium oxide as star.ing *** study investigated the effect of differ.nt star.ing r.agents on the synthesis of Ba_(0.8)ca_(0.2)tiO_(3)(BCt)by complex polymer.zation method(CPM).two sets of star.ing pr.cur.or. wer. used:titanium citr.te,caCO_(3)and BaCO3,and titanium citr.te and Ba1-xcaxCO3 solid solution *** wer. cr.stallized at a temper.tur. r.nge fr.m 400℃to 700℃for.differ.nt *** obtained powder. wer. char.cter.zed by X-r.y diffr.ction(Xr.),ther.ogr.vimetr.(tG)and differ.ntial ther.al analysis(DtA),and r.man and infr.r.d *** infr.r.d spectr.scopy indicated that the chelation pr.cesses of Ba,ca,ti and ca ions ar. ver. *** r.sults showed that the use of caCO_(3)and BaCO3 or.Ba1-xcaxCO3 solid solution as pr.cur.or. does not affect the final pr.per.ies of BCt powder. obtained by CPM.

关键词： cer.mic synthesis Ba_(0.8)ca_(0.2)tiO_(3)(BCt) complex polymer.zation method(CPM)

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Suppr.ssion of the Exter.al Mitochondr.alnADPH Dehydr.genase, nDB1, in Ar.bidopsisthaliana Affects Centr.l Metabolism andVegetative Gr.wth

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Molecular.Plant 2014年第2期7卷 356-368页

作者： Sabá V. Wallstr.m Igor.Flor.z-Sar.sa Wagner.L. Ar.újo.mar. Aidemar. mar.a Fer.ández-Fer.ández Alisdair.r. Fer.ie Miquel r.bas-car.ó Allan G. r.smusson Depar.ment of Biology Lund University Biology building Sölvegatan 35 SE-223 62 Lund Sweden Gr.p de r.cer.a en Biologia de les Plantes en Condicions Mediter.ànies Universitat de les Illes Balears Ctra Valldemossa Km. 75 07122 Palma de Mallorca Spain Pr.sent addr.ss: max-Planck-Institut für.Molekular. Pflanzenphysiologie Am Mühlenberg 1 14476 Potsdam-Golm Germany max-Planck-Institut für.Molekular. Pflanzenphysiologie Am Mühlenberg 1 14476 Potsdam-Golm Germany Pr.sent addr.ss: Depar.amento de Biologia Vegetal Universidade Federal de Viçosa 36570-000 Viçosa Minas Gerais Brasil

ca2＋-dependent oxidation of cytosolic nADPH is mediated by nDB1, which is an exter.al type II nADPHdehydr.genase in the plant mitochondr.al electr.n tr.nspor. chain. Using r.A inter.er.nce, the nDB1 tr.nscr.pt wassuppr.ssed by 80% in Ar.bidopsis thaliana plants, and exter.al ca2＋-dependent nADPH dehydr.genase activity becameundetectable in isolated mitochondr.a. this was linked to a decr.ased level of nADP＋ in r.settes of the tr.nsgenic ***-gr.wn tr.nsgenic seedlings displayed decr.ased gr.wth specifically on glucose, and r.spir.tor. metabolism of 14C-glucose was incr.ased. On soil, nDBl-suppr.ssing plants had a decr.ased vegetative biomass, but leaf maximumquantum efficiency of photosystem Ⅱ and CO2 assimilation r.tes, as well as total r.spir.tion, wer. similar.to the wild-type. the in vivo alter.ative oxidase activity and ca.a.ity wer. also similar.in all genotypes. Metabolic pr.filing r.vealeddecr.ased levels of sugar., citr.c acid cycle inter.ediates, and amino acids in the tr.nsgenic lines. the nDBl-suppr.ssioninduced tr.nscr.ptomic changes associated with pr.tein synthesis and glucosinolate and jasmonate metabolism. thetr.nscr.ptomic changes also over.apped with changes obser.ed in a mutant lacking ABAInSEnSItIVE4 and in A. thalianaover.xpr.ssing str.ss toler.nce genes fr.m r.ce. the r.sults thus indicate that A. thaliana nDB1 modulates nADP（H）r.duction levels, which in tur. affect centr.l metabolism and gr.wth, and inter.ct with defense signaling.

关键词： citr.c acid cycle metabolic pr.filing mitochondr.al r.spir.tion nADPH r.A inter.er.nce type II nAD(P)Hdehydr.genase vegetative gr.wth

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Pr.filing Chr.matin Accessibility at Single-cell r.solution

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Genomics, Pr.teomics & Bioinfor.atics 2021年第2期19卷 172-190页

作者： Sar.hak Sinha Ansuman t.Satpathy Weiqiang Zhou Hongkai Ji jo.A.Str.tton Ar.ina Jaffer.nizar.Bahlis Sor.na Mor.issy Jeff A.Bier.askie Depar.ment of Compar.tive Biology&Exper.mental Medicine Faculty of Veterinary MedicineUniversity of CalgaryCalgaryAB T2N 4N1Canada Depar.ment of Pathology Stanford University School of MedicineStanfordCA 94305USA Depar.ment of Biostatistics Bloomberg School of Public HealthJohns Hopkins UniversityBaltimoreMD 21205USA Alber.a Childr.n’s Hospital r.sear.h Institute University of CalgaryCalgaryAB T2N 4N1Canada Hotchkiss Br.in Institute University of CalgaryCalgaryAB T2N 4N1Canada Ar.ie Char.onneau cancer.Institute University of CalgaryCalgaryAB T2N 4Z6Canada Depar.ment of Biochemistr. and Molecular.Biology Cumming School of MedicineUniversity of CalgaryCalgaryAB T2N 4N1Canada

How distinct tr.nscr.ptional pr.gr.ms ar. enacted to gener.te cellular.heter.geneity and plasticity,and enable complex fate decisions ar. impor.ant open *** key r.gulator.is the cell’s epigenome state that dr.ves distinct tr.nscr.ptional pr.gr.ms by r.gulating chr.matin ***-wide chr.matin accessibility measur.ments can impar. insights into r.gulator. sequences(in)accessible to DnA-binding pr.teins at a single-cell *** r.view outlines molecular.methods and bioinfor.atic tools for.captur.ng cell-to-cell chr.matin var.ation using single-cell assay for.tr.nsposase-accessible chr.matin using sequencing(sca.a.-seq)in a sca.a.le *** also cover. jo.nt pr.filing of chr.matin with tr.nscr.ptome/pr.teome measur.ments,computational str.tegies to integr.te multi-omic measur.ments,and pr.dictive bioinfor.atic tools to infer.chr.matin accessibility fr.m single-cell tr.nscr.ptomic *** r.finements that incr.ase power.for.cell discover. thr.ugh r.bust chr.matin cover.ge and integr.te measur.ments fr.m multiple modalities will fur.her.expand our.under.tanding of gene r.gulation dur.ng homeostasis and disease.

关键词： Single-cell AtAC-seq Gene r.gulation Epigenetics Single-cell multi-omics Cis-r.gulator. elements

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Pr.per.ies of Chemically Synthesized nano-geopolymer.Cement based Self-Compacting Geopolymer.Concr.te(SCGC)

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jo.r.al of Wuhan Univer.ity of technology(mater.als Science) 2019年第1期34卷 98-106页

作者： Muhammad Ali Sikandar.Byung Wan jo.Zafar.Baloch Muhammad Asad Khan Depar.ment of Civil and Envir.nmental Engineer.ng Hanyang University Depar.ment of Civil and Envir.nmental Engineer.ng CECOS University

the physical and mechanical pr.per.ies of self-compacting geopolymer.concr.te(SCGC) using chemically synthesized nano-geopolymer.cement was investigated. nano-geopolymer.cement was synthesized using nano-silica, alkali activator. and sodium aluminate in the labor.tor.. Subsequently, nine nanogeopolymer.cement sbased SCGC mixes with var.ing nano-geopolymer.cement content, alkali activator.content, coar.e aggr.gate(ca) content, and cur.ng temper.tur. wer. pr.duced. the wor.ability-r.lated fr.sh pr.per.ies wer. assessed thr.ugh slump flow diameter.and slump flow r.te measur.ments. Mechanical per.or.ances wer. evaluated thr.ugh compr.ssive str.ngth, splitting tensile str.ngth, and modulus of elasticity measur.ments. In addition, r.pid chlor.de penetr.tion test, water.absor.tion, and por.sity tests wer. also per.or.ed. It was assessed that all mix design par.meter. influenced the fr.sh and har.ened pr.per.ies of SCGC mixes. Based on test r.sults, it was deduced that nano-geopolymer.cement SCGC per.or.ed fair.y well. All the SCGC mixes achieved the 28-day compr.ssive str.ngth in the r.nge of 60-80 MPa. Additionally, all mixes attained 60% of their.28-day str.ngth dur.ng the fir.t thr.e days of elevated temper.tur. cur.ng. FtIr.and SEM analyses wer. per.or.ed to evaluate the degr.e of polymer.zation and the micr.str.ctur. r.spectively for.SCGC mixes.

关键词： geopolymer compr.ssive str.ngth self-compacting concr.te alkali activator nano-silica

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condLStM-Q: A novel deep lear.ing model for.pr.dicting COVID-19 mor.ality in fine geogr.phical scale

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Quantitative Biology 2022年第2期10卷 125-138页

作者： HyeongChan jo.Juhyun Kim tzu-Chen Huang Yu-Li ni Division of Biology and Biological Engineer.ng CaltechPasadena CA 91125USA the Division of Physics Mathematics and AstronomyCaltechPasadena CA 91125USA Walter.Bur.e Institute for.theor.tical Physics CaltechPasadena CA 91125USA

Backgr.und: Moder. machine lear.ing-based models have not been har.essed to their.total ca.a.ity for.disease tr.nd pr.dictions pr.or.to the COVID-19 pandemic. this wor. is the fir.t use of the conditional r.n model in pr.dicting disease tr.nds that we know of dur.ng development that complemented classical epidemiological ***: We developed the long shor.-ter. memor. networ.s with quantile output (condLStM-Q) model for.making quantile pr.dictions on COVID-19 death ***: We ver.fied that the condLStM-Q was accur.tely pr.dicting fine-scale, county-level daily deaths with a two-week window. the model’s per.or.ance was r.bust and compar.ble to, if not slightly better.than well-known, publicly available models. this pr.vides unique oppor.unities for.investigating tr.nds within the states and inter.ctions between counties along state bor.er.. In addition, by analyzing the impor.ance of the categor.cal data, one could lear. which featur.s ar. r.sk factor. that affect the death tr.nd and pr.vide handles for.officials to amelior.te the ***: the condLStM-Q model per.or.ed r.bustly, pr.vided fine-scale, county-level pr.dictions of daily deaths with a two-week window. Given the sca.a.ility and gener.lizability of neur.l networ. models, this model could incor.or.te additional data sour.es with ease and could be fur.her.developed to gener.te other.valuable pr.dictions such as new cases or.hospitalizations intuitively.

关键词： COVID-19 machine lear.ing deep lear.ing epidemiology time ser.es for.cast

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High-power.and long-life super.0}itive per.or.ance of hier.r.hical, 3-D ur.hin-like W18049 nanostr.ctur. electr.des

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nano r.sear.h 2016年第3期9卷 633-643页

作者： Sangbaek Par. Hyun-Woo Shim Chan Woo Lee Hee jo.Song Jae-Chan Kim Dong-Wan Kim Depar.ment of mater.als Science and Engineer.ng Seoul National University Seoul 151-744 Republic of Korea School of Civil Environmental and Architectural Engineering Korea University Seou1136-713 Republic of Korea

We r.por. the facile, one-pot synthesis of 3-D ur.hin-like W18O49 nanostr.ctur.s （U-WO） via a simple solvother.al appr.ach. An excellent super.0}itive per.or.ance was achieved by the U-WO because of its lar.e Br.nauer.Emmett- teller.（BEt） specific sur.ace ar.a （ca. 123 m2.g-1） and unique mor.hological and str.ctur.l featur.s. the U-WO electr.des not only exhibit a high r.te-ca.a.ility with a specific ca.a.itance （Csp） of -235 F·g-1 at a cur.ent density of 20 A.g-1, but also super.or.long-life per.or.ance for.1,000 cycles, and even up to 7,000 cycles, showing -176 F·g-1 at a high cur.ent density of 40 A.g-1.

关键词： hier.r.hical str.ctur. W18O49 high-power long cycle life super.0}itor

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Behavior.of caO and calcium in pur. magnesium

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r.r. Metals 2006年第Z2期25卷 150-154页

作者： HA Seong-Ho LEE Jin-Kyu jo.Hyung-Ho JUnG Seung-Boo KIM Shae K. Depar.ment of Advanced mater.al Engineer.ng Sungkyunkwan University 300 Chunchun-dong Jangan-gu Suwon Gyunggi-do 440-746 KoreaAdvanced Material Division Korea Institute of Industrial Technology 7-47 Songdo-dong Yeonsu-gu Incheon 406-840 Korea Advanced mater.al Division Korea Institute of Industrial Technology 7-47 Songdo-dong Yeonsu-gu Incheon 406-840 Korea Depar.ment of Advanced mater.al Engineer.ng Sungkyunkwan University 300 Chunchun-dong Jangan-gu Suwon Gyunggi-do 440-746 Korea

Mg alloys exhibit a number.of good pr.per.ies such as low density, good castability and high specific str.ngth. However. molten Mg and Mg alloys ar. ignited without the melt pr.tective gases dur.ng melting and casting pr.cess due to their.high r.activity. the pur.ose of this study is to investigate effects of ca.a.d caO on pur. Mg thr.ugh micr.str.ctur. obser.ation, ignition test and phase analysis. With incr.asing ca.a.d caO contents, the ignition r.sistance of ca or.caO added pur. Mg is incr.ased and the gr.ins ar. r.fined. As r.sults of Xr. and EDS, caO is r.duced to ca in caO added pur. Mg. Mg2ca phase is for.ed even in 0.1 wt.%caO added pur. Mg by r.duction mechanism, while Mg2ca phase is for.ed over.1.35 wt.% ca.a.ded pur. Mg.

关键词： Mg caO ignition r.sistance Mg2ca phase

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