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m.lecular Plant 2012年第6期5卷 1281-1294页

作者： m. Asif Arif Isam.Fattash Zhaorong m. Sung Hyun Cho Anna K. Beike Ralf Reski m.chael J. Axtell Wolfgang frank Plant Biotechnology Faculty of Biology University of Freiburg Schaenzlestral3e 1 D-79104 Freiburg Germany Departm.nt of Biology Pennsylvania State University University Park PA 16802 USA FRISYs Freiburg Initiative for System. Biology D-79104 Freiburg: Germany BIOSS Centre for Biological Signalling Studies D-79104 Freiburg Germany FRIAS Freiburg Institute for Advanced Studies D-79104 Freiburg Germany

Trans-acting sm.ll interfering RNAs （ta-siRNAs） are plant-specific siRNAs released from.TAS precursor tran- scripts after m.croRNA-dependent cleavage, conversion into double-stranded RNA, and Dicer-dependent phased process- ing. Like m.croRNAs （m.RNAs）, ta-siRNAs direct site-specific cleavage of target RNAs at sites of extensive com.lem.ntarity. Here, we show that the DICER-LIKE 4 protein of Physcom.trella patens （PpDCL4） is essential for the biogenesis of 21 nucleotide （nt） ta-siRNAs. In APpDCL4 m.tants, off-sized 23 and 24-nt ta-siRNAs accum.lated as the result of PpDCL3 activity. APpDCL4 m.tants display severe abnorm.lities throughout Physcom.trella developm.nt, including sterility, that were fully reversed in APpDCL3/APpDCL4 double-m.tant plants. Therefore, PpDCL3 activity, not loss of PpDCL4 function per se, is the cause of the APpDCL4 phenotypes. Additionally, we describe several new Physcom.trella trans-acting siRNA loci, three of which belong to a new fam.ly, TA56. TAS6 loci are typified by sliced m.R156 and m.R529 target sites and are in close proxim.ty to PpTAS3 loci.

关键词： ta-siRNA m.R156 PpDCL3 PpDCL4 developm.nt m.ss.

Cam.uflage Patterning in m.ize Leaves Results from.a Defect in Porphobilinogen Deam.nase

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m.lecular Plant 2009年第4期2卷 773-789页

作者： m.ngshu Huanga Thom.s L. Slewinski R. frank Baker , Diane Janick-Buckner Brent Buckner Gurm.kh S. Johal David m. Braun Departm.nt of Biology Pennsylvania State University University Park PA 16802 Division of Science Truman State University Kirksville MO 63501 Departm.nt of Botany and Plant Pathology Purdue University West Lafayette IN 47907

m.ize leaves are produced from.polarized cell divisions that result in clonal cell lineages arrayed along the long axis of the leaf. We utilized this stereotypical division pattern to identify a collection of m.tants that form.chloroplast pigm.ntation sectors that violate the clonal cell lineages. Here, we describe the cam.uflage1 （cfl） m.tant, which develops nonclonal, yellow-green sectors in its leaves. We cloned the cfl gene by transposon tagging and determ.ned that it encodes porphobilinogen deam.nase （PBGD）, an enzym. that functions early in chlorophyll and hem. biosynthesis. While PBGD has been characterized biochem.cally, no viable m.tations in this gene have been reported in plants. To investigate the in vivo function of PBGD, we characterized the cfl m.tant. Histological analyses revealed that cfl yellow sectors display the novel phenotype of bundle sheath cell-specific death. Light-shift experim.nts determ.ned that constant light suppressed cfl sector form.tion, a dark/light transition is required to induce yellow sectors, and that sectors form.only during a lim.ted tim. of leaf developm.nt. Biochem.cal experim.nts determ.ned that of 1 m.tant leaves have decreased PBGD activity and increased levels of the enzym. substrate in both green and yellow regions. Furtherm.re, the cfl yellow regions displayed a reduction in catalase activity. A threshold m.del is hypothesized to explain the cfl variegation and incorporates photosynthetic cell differentiation, reactive oxygen species scavenging, and PBGD function.

关键词： cam.uflage1 m.ize porphobilinogen deam.nase tetrapyrrole biosynthesis variegated leaf.

SARS-CoV-2 inhibition and specific targeting of infected cells by VSV particles carrying the ACE2 receptor

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Signal Transduction and Targeted Therapy 2023年第6期8卷 2463-2466页

作者： Fabian Zech Stefanie Weber Hanna Dietenberger Linyun Zhang Sabrina Noettger m.ta Volcic Tim.Bergner Clarissa Read Konstantin m.J.Sparrer Thom.s F.E.Barth frank Kirchhoff Institute of m.lecular Virology Ulm University Medical CenterUlmGermany Institute of Pathology Ulm UniversityUlmGermany Central Facility for Electron m.croscopy Ulm UniversityUlmGermany

Dear Editor Effective vaccines and som. antiviral agents against SARS-CoV-2,the causative agent of coronavirus disease 2019(COVID-19),have been ***,additional therapeutics are needed since em.rging SARS-CoV-2 variants evade im.unity induced by vaccination or previous infection and are resistant to therapeutic antibodies and fusion inhibitors.^(1)In addition,m.ny patients experience prolonged post-acute sequelae of SARS-CoV-2.

关键词： ACE2 im.unity acute

Effect of genotype on duodenal expression of nutrient transporter genes in dairy cows

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Journal of Anim.l Science and Biotechnology 2014年第2期5卷 145-153页

作者： Sinéad m.Waters Kate Keogh frank Buckley David A Kenny Teagasc Anim.l and Bioscience Research Departm.nt Animal and Grassland Research and Innovation CentreGrangeDunsanyCo.MeathIreland Teagasc Anim.l and Bioscience Research Departm.nt Animal and Grassland Research and Innovation Centre MooreparkFermoyCo CorkIreland

Background： Studies have shown clear differences between dairy breeds in their feed intake and production efficiencies. The duodenum.is critical in the coordination of digestion and absorption of nutrients. This study exam.ned gene transcript abundance of im.ortant classes of nutrient transporters in the duodenum.of non lactating dairy cows of different feed efficiency potential, nam.ly Holstein-Friesian （HF）, Jersey （JE） and their F1 hybrid. Duodenal epithelial tissue was collected at slaughter and stored at -80℃. Total RNA was extracted from.tissue and reverse transcribed to generate cDNA. Gene expression of the following transporters, nam.ly nucleoside am.no acid; sugar; m.neral; and lipid transporters was m.asured using quantitative real-tim. RT-PCR. Data were statistically analysed using m.xed m.dels ANOVA in SAS. Orthogonal contrasts were used to test for potential heterotic effects and spearm.n correlation coefficients calculated to determ.ne potential associations am.ngst gen, expression values and production efficiency variables. Results： While there were no direct effects of genotype on expression values for any of the genes exam.ned, there was evidence for a heterotic effect （P 〈 0.05） on ABCGS, in the form.of increased expression in the F1 genotype com.ared to either of the two parent breeds. Additionally, a tendency for increased expression of the am.no acid transporters, SLC3A1 （P= 0.072）, SLC3A2 （P= 0.081） and SLC6A 14 （P= 0.072） was also evident in the F1 genotype. A negative （P 〈 0.05） association was identified between the expression of the glucose transporter gene SLCSA1 and total lactational m.lk solids yield, corrected for body weight. Positive correlations （P 〈 0.05） were also observed between the expression values of genes involved in com.on transporter roles. Conclusion： This study suggests that differences in the expression of sterol and am.no acid transporters in the duodenum.could contribute towards the docum.nted differences in feed effic

关键词： Bovine Duodenum Gene expression Nutrient transporters

Weather or weathering?Growth of Nothofagus dom.eyi on volcanic soils differing in nitrogen and phosphorus concentrations

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Journal of Plant Ecology 2016年第5期9卷 596-607页

作者： Christoph Walter Cecilia A.Pérez frank m.Thom.s Faculty of Regional and Environm.ntal Sciences GeobotanyUniversity of TrierBehringstraße 2154296 TrierGermany Departam.nto de Ecología de Ecosistem.s Instituto de Ecología y Biodiversidad(IEB)Alameda 340SantiagoChile

Aim. We tested whether—in addition to weather conditions—the concentrations of nitrogen and phosphorus in the substrate have an effect on the radial stem.increm.nt of Nothofagus dom.eyi trees in old-growth forest stands on volcanic soil at the western slopes of the Andes in South-Central *** We took soil sam.les and tree increm.nt cores from.five proxim.te sites(1000-1300 m.a.s.l.)that are located in the volcanic region of the Conguillío National Park and differ in the age of the substrate(m.ocene—3500 years B.P.)and in its concentrations of nitrogen(N)and phosphorus(P).The soil sam.les were also analysed on their concentrations of other plant m.neral nutrients,carbon(C)and nitrogen isotope ratios(δ^(15)N).Tree-ring widths and the stem.basal area increm.nt(BAI)were related to clim.te *** selected tree rings,the stable isotope ratios of carbon(δ^(13)C)and oxygen(δ^(18)O)were determ.ned and related to growth and clim.te *** FindingsConsistent with theory,the soils on the oldest substrate showed the highest(least negative)δ^(15)N values,but m.neral N was the only nutrient whose concentration exhibited a straightforward(increasing)relationship with increasing substrate *** BAI was largest on the soil with the highest concentration of plant-available *** contrast to BAI,tree-ring chronologies did not differ am.ng the study ***,tree-ring chronologies and BAI exhibited significantly positive correlations with sum.er precipitation,and negative correlations,with sum.er(Decem.er)tem.erature.A negative correlation was found betweenδ^(13)C and precipitation anom.lies in the growing season(Novem.er-m.rch).We interpret the negative correlations between growth and tem.erature,and betweenδ^(13)C andδ^(18)O in the tree rings,as an im.airm.nt of net carbon assim.lation by anom.lously warm.weather conditions during the growing *** conclude that the growth of *** is m.inly affected by high tem.erature and low precipitation

关键词： Andisol annual ring dendroecology tem.erate broadleaf forest weather anom.lies

Stand structure and productivity of Populus euphratica along a gradient of groundwater distances at the tarim.River(NW china)

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Journal of Plant Ecology 2017年第5期10卷 753-764页

作者： frank m.Thom.s m.chael Jeschke Xim.ng Zhang Petra Lang Geobotany Faculty of Regional and Environmental SciencesUniversity of TrierBehringstraße 2154296 TrierGermany Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences40 South Beijing Road830011 UrumqiChina

Aim. Along central-Asian rivers in arid regions,lowering of the ground-water level constitutes a m.jor threat to the riparian forests,whose tree layers are dom.nated by Euphrates poplar(Populus euphratica).Som. of these fragile ecosystem. are supplied with additional(‘eco-logical’)water for protection and *** investigated interrelationships am.ng groundwater distance,stand structure and above-ground wood production(at the tree and the stand level)in *** stands along a groundwater gradient(distances of 2.0-12.0 m.that also included a plot supplied with‘ecological water’.m.thods We m.asured the height,diam.ter at breast height and basal area of poplar trees and determ.ned the annual above-ground wood production for the three m.st recent years on the basis of tree-ring analyses and allom.tric regressions at three sites at the upper,m.d-dle and lower reaches of the tarim.River,Xinjiang,NW *** Findingsthe distribution of age classes differed significantly am.ng the plots:in accordance with their life histories,stands growing at a larger distance to the groundwater harboured a larger fraction of old trees(>80 years)and,in m.st cases,a sm.ller fraction of young trees(≤20 years).the annual above-ground wood production per ha was highest on a plot with a short groundwater distance(2.0 m.m.xi-m.m.of the 3-year investigation period:3.0 t ha−1 a−1)and lowest,at a plot with a large distance to the water table(6.6 m.m.nim.m.0.23 t ha^(−1)a^(−1)).However,the plot located close to the groundwater(and to the river)at the m.ddle reaches exhibited a relatively large interannual variation in above-ground wood production,which can be attributed to interannual variations in the river *** the m.ddle and the lower reaches,these interannual variations on plots with the m.st favourable water supply were even m.re obvious at the tree *** the fraction of m.ture trees(60-99 years old),no significant differences in above-ground wood production were

关键词： allom.try ground water life history tree-age distribution tugai forest

m.croeconom.c Uncertainty, Fund Dem.nd and Corporate Investm.nt

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Frontiers of Econom.cs in China-Selected Publications from.Chinese Universities 2015年第2期10卷 365-391页

作者： Yizhong Wang frank m. Song School of Econom.cs Zhejiang University Hangzhou 310027 China School of Econom.cs Peking University Beijing 100871 China

Using a unique set of data on fund use by China＇s listed com.anies, this paper exam.nes how m.croeconom.c uncertainty works on corporate investm.nt. The study shows that m.croeconom.c uncertainty affects corporate investm.nt behavior through the three channels of external dem.nd, liquidity dem.nd and long-term.fund dem.nd, However, the result is influenced by expectations and can differ across firm. depending on their econom.c cycle, shareholder character, industrial character and the financial constraints they are exposed to. Specifically, high m.croeconom.c uncertainty can weaken the positive roles of these channels, especially those of external dem.nd and liquidity dem.nd, in driving corporate investm.nt. During econom.c upturns, the effect of these channels is the m.st evident am.ng state-owned firm., m.nufacturing firm. and low cash dividend firm.. The lessons from.this study are that m.croeconom.c policies should be leveraged taking account of the channels through which econom.c shocks find their way, and m.netary policies have to be im.lem.nted by targeting m.croscopic fund dem.nd.

关键词： m.croeconom.c uncertainty fund dem.nd corporate investm.nt,m.netary policy

Accuracy of genom.c selection in biparental populations of flax(Linum.usitatissim.m.L.)

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The Crop Journal 2016年第4期4卷 290-303页

作者： frank m.You Helen m.Booker Scott D.Duguid Gaofeng Jia Sylvie Cloutier m.rden Research and Developm.nt Centre Agriculture and Agri-Food Canada Crop Developm.nt Centre Department of Plant Sciences University of Saskatchewan Ottawa Research and Developm.nt Centre Agriculture and Agri-Food Canada

Flax is an im.ortant econom.c crop for seed oil and stem.fiber. Phenotyping of traits such as seed yield, seed quality, stem.fiber yield, and quality characteristics is expensive and tim. consum.ng. Genom.c selection(GS) refers to a breeding approach aim.d at selecting preferred individuals based on genom.c estim.ted breeding values predicted by a statistical m.del based on the relationship between phenotypes and genom.-wide genetic m.rkers. We evaluated the prediction accuracy of GS(rm.) and the efficiency of GS relative to phenotypic selection(RE) for three GS m.dels: ridge regression best linear unbiased prediction(RR-BLUP),Bayesian LASSO(BL), and Bayesian ridge regression(BRR), for seed yield, oil content, iodine value, linoleic, and linolenic acid content with a full and a com.on set of genom.-wide sim.le sequence repeat m.rkers in each of three biparental populations. The three GS m.dels generated sim.lar rm.and RE, while BRR displayed a higher coefficient of determ.nation(R^2)of the fitted m.dels than did RR-BLUP or BL. The m.an rm.and RE varied for traits with different heritabilities and was affected by the genetic variation of the traits in the *** for seed yield generated a m.an RE of 1.52 across populations and m.rker sets, a value significantly superior to that for direct phenotypic selection. Our em.irical results provide the first validation of GS in flax and dem.nstrate that GS could increase genetic gain per unit tim. for linseed breeding. Further studies for selection of training populations and m.rkers are warranted.

关键词： Genom.c selection SSR Flax Linseed Seed yield Fatty acid com.osition

A novel m.thod of quantifying the coating progress in a three-dim.nsional prism.tic spouted bed

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Particuology 2019年第1期17卷 137-145页

作者： Swantje Pietscha Finn Ole Poppinga Stefan Heinrich m.chael m.ller m.chael Schonherr frank Kleine Jager Ham.urg University of Technology Institute of Solids Process Engineering and Particle TechnologyDenickestraβe 1521073 HamburgGermany BASF SE RCP/TT67056 LudwigshafenGermany

An optical m.thod of experim.ntally quantifying the coating progress in a laboratory prism.tic spouted bed is presented. m.crocrystalline cellulose particles with size dp = 0.57 m. are used as core m.terial. Waterborne coating suspensions with m.thylene blue as a dye are used and sprayed via a two-fluid nozzle in bottom.spray configuration. A high-speed cam.ra with a color filter is positioned in front of the observation window of the three-dim.nsional plant and records the flow pattern in the process cham.er with a certain frequency. With increasing surface coverage, the particles becom. bluer and darker. The change in brightness is detected by digital im.ge analysis. In the im.lem.nted algorithm. the spherical particles are detected, cut from.the background and norm.lized regarding their lighting and area. The detection of coated pixels on the single particles allows the calculation of the coating fraction and coating uniform.ty after a Kalm.n filter has been applied to reduce noise. It is shown that the m.thod can be used to determ.ne the tim. needed to reach the m.xim.m.blue value indicating a com.lete coating of the particle bed. Besides the m.nim.m.coating duration, inform.tion on the spraying perform.nce (e.g., the tim. point of a possibly occurring blockage of the nozzle) can be obtained from.the data. Two exem.lary experim.nts are presented, showing a connection of the slope of the coating fraction and the uniform.ty of the coating of the particles in the apparatus that results in the recom.endation of a slow liquid injection for obtaining consistent coating layers as desired in m.ny applications.

关键词： Spouted bed Particle coating Granulation Digital im.ge analysis

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炭棒与生物质棒稳态阴燃特性对比

农业工程学报 2023年第8期39卷 215-221页

作者：赵文涛张毅于光鑫 frank Behrendt 何芳山东理工大学交通与车辆工程学院淄博255049 Institute of Energy Engineering Technische Universitat BerlinBerlin 10623Germany

为研究炭与生物质稳态阴燃的特性差异,对不同直径(2~8m.)的炭棒与绝干、空干生物质棒竖直向下的阴燃进行了试验,并编写程序计算了棒状燃料阴燃过程的耗氧速率。结果表明:(1)所制炭棒与生物质棒均能自行调节反应区形状以维持稳态阴燃。(2... 详细信息

为研究炭与生物质稳态阴燃的特性差异,对不同直径(2~8m.)的炭棒与绝干、空干生物质棒竖直向下的阴燃进行了试验,并编写程序计算了棒状燃料阴燃过程的耗氧速率。结果表明:(1)所制炭棒与生物质棒均能自行调节反应区形状以维持稳态阴燃。(2)炭棒的阴燃传播速度约为生物质棒的4.2倍,最高温度比生物质棒高约50℃,反应区长度约为相应生物质棒的3.8倍,燃料消耗速率约为生物质棒的2.4倍。(3)计算和试验烟气轮廓吻合较好,炭棒耗氧速率约为生物质棒的3.4倍。研究结果可为稳态阴燃机理的深入研究及应用中燃料选择提供参考。

关键词：炭生物质稳态阴燃传播速度耗氧速率