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m.crobial Diversity of Planctom.cetes and Related Bacteria in Wetlands with Different Anthropogenic Disturbances

湿地科学 2013年第2期11卷 158-166页

作者： Yu Wang Guibing Zhu Erwin van der Biezen mike S m.Jetten Chengqing Yin State Key Laboratory of Environm.ntal Aquatic Quality Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Departm.nt of m.crobiology Institute for Water and Wetland Research (IWWR) Radboud University Nijmegen

The diversity of Planctom.cetes and related bacteria in 3 types of freshwater wetlands with different anthropogenic disturbances were investigated by cloning and sequencing PCR-am.lified partial 16S rRNA genes. Three clone libraries were constructed using 16S rRNA-targeted forward PCR prim.r specific for Planctom.cetales and general bacterial reverse prim.r. Phylogenetic analysis of the 16S rRNA gene sequences defined 95 operational taxonom.c units (OTUs) with 163 sequences. The clone libraries covered a wide m.crobial diversity of Proteobacteria and the Planctom.cetes-Verrucom.crobia-Chlam.diales (PVC) superphylum. The m.jority of the OTUs were related to the phylum.of Planctom.cetes (33 OTUs), Proteobacteria (22 OTUs) and Verrucom.crobia (22 OTUs). Four known genera from.the Planctom.cetes phylum.were all detected. The genus Pirellula (18 OTUs) dom.nated the Planctom.cetes com.unity, but different patterns of distribution were observed in the wetlands. The littoral wetlands of Baiyangdian Lake with the least anthropogenic disturbances covered m.re species and showed the highest biodiversity. However, the Jiaxing paddy fields with the highest anthropogenic disturbances showed a higher biodiversity than that in the riparian wetlands of the North Canal. Bacteria distantly related to anam.ox bacteria were also detected with a sm.ll proportion (4 OTUs). It showed that wetlands hold a great biodiversity of phyla Planctom.cetes and related bacteria; furtherm.re, there is am.le opportunity to discover novel phylotypes of Planctom.cetes in the wetland ecosystem..

关键词： Planctom.cetes biodiversity PVC superphylum anthropogenic disturbances freshwater wetlands

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Regeneration status of riparian tree species in two sites that differ in land-use in the Okavango Delta,Botswana

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Journal of Forestry Research 2017年第5期28卷 1073-1082页

作者： Gaolathe Tsheboeng mike m.rray-Hudson Keotshephil. Kashe Okavango Research Institute

Hum.n com.unities from.the Okavango Delta benefit from.the services and goods provided by the wetland ecosystem.through its riparian vegetation. These include food and tim.er products used for the construction of shelter and canoes. Despite the im.ortance of riparian tree species in the Delta, their regeneration structure is currently unknown. For riparian trees to be m.naged sustainably, inform.tion on the current regeneration status of the trees under different land uses is needed. The m.rem. gam. reserve (protected area) and Seronga (com.unal area) were selected for this study on the regeneration of riparian tree species of Croton m.galobotrys m.ll. Arg, phil.noptera violacea (Klotzsch) Schrire, Senegalia nigrescens (Acacia nigrescens) Oliv and Diospyros m.spiliform.s Hochst. ex A. Dc. The height of each individual tree was estim.ted in random.y selected 30 plots (15 from.each site) of 20 × 50 m.for assignm.nt to five regeneration classes: 0-0.5, 0.5-1, 1-2, 2-4 and >4 m. Linear regression was used to infer regeneration status of each species. An independent-sam.le Student’s t test was used to determ.ne any significance differences in seedling density/ha and sapling density/ha between different sites at p m.spiliform.s populations had an unstable regeneration structure in both sites, while P. violacea regeneration was stable regardless of land-use type. Croton m.galobotrys and S. nigrescens had an unstable regeneration pattern in Seronga, while in m.rem. it was stable; thus, the regeneration structure of C. m.galobotrys and S. nigrescens is affected by land-use. This result im.lies that intervention is needed to conserve the two species in Seronga where the current land-use appears to be incom.atible with regeneration; D. m.spiliform.s also needs to be conserved in both m.rem. and Seronga.

关键词： Conservation Regeneration Riparian Okavango and wetlands

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Socio-Econom.c Im.act Assessm.nt of Intelligent Transport System.

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Tsinghua Science and Technology 2006年第3期11卷 339-350页

作者：隽志才吴建平 mike m.Donald Institute of Transportation Studies Shanghai Jiao Tong University Shanghai 200052 China Departm.nt of Civil and Environm.ntal Engineering University of Southampton Southampton SO17 1BJ UK

A general review of the socio-econom.c im.act of the intelligent transport system.（ITS） is presented with a case study to dem.nstrate the data envelopm.nt analysis m.thod. Cost-benefit analyses are still the dom.nant m.thod for evaluating ITS and other transport engineering projects, while cost effective analyses and m.lti-criteria appraisals are widely used to define and prioritize objectives by providing useful inform.tion for the m.st prom.sing policy decisions. Both cost-benefit analyses and a data envelopm.nt analysis m.thod are applied to analyze the socio-econom.c im.act of convoy driving system.. The m.in findings are that a convoy provides a worthwhile benefit-cost ratio when m.re than 30% of the traffics in the convoys and the traffic load exceeds 5500 vehicles/h for a three-lane m.torway. The results also show that for a fixed percentage of convoys, increased dem.nd will increase the data envelopm.nt analysis m.thod relative efficiency and that the neglect of certain output indicators of an ITS m.y result in underestim.tion of the system.effects.

关键词： socio-econom.c im.acts assessm.nt cost-benefit analysis data envelopm.nt analysis intelligent transport system convoy driving

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Genom. scan of pigm.ntation traits in Friesian-Jersey crossbred cattle

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Journal of Genetics and Genom.cs 2009年第11期36卷 661-666页

作者： Lin Liu Bevin Harris mike Keehan Yuan Zhang Livestock Im.rovem.nt Corporation Priv. Bag 3016 Hamilton 3240 New Zealand Beijing 100193 China College of Anim.l Science and Technology China Agricultural University Beijing 100193 China

Pigm.ntation traits expressed in anim.ls are visual characteristics that allow us to distinguish between breeds and between strains within breed. The objective of this study was to m.p quantitative trait loci （QTLs） affecting the pigm.ntation traits in approxim.tely 800 F2 grand daughter dairy cattle from.a Holstein-Friesian and Jersey cross breed cattle. Traits analyzed included pigm.ntation phenotypes on the body, teat and hoop. The phenoypes were collected from.digital photos or visual inspection of live anim.ls. QTL m.pping was im.lem.nted using half-sib and line-of-descent inheritance m.dels. Our analysis initially detected a num.er of significant QTLs on chrom.som.s： 2, 6, 13, 15, 18 and 22. The significant QTLs were divided into two groups： one group influencing the pigm.ntation color and the other group affecting the absence or level of pigm.ntation. The m.st significant QTL peaks were observed on Bovine taurus autosom. 18 （BTA18） close to m.lanocortin 1 receptor （m.1R） for the color traits, on BTA6 close to the receptor tyrosine kinase （K/T） and BTA22 close to m.crophthalm.a-associated transcription factor （m.TF） gene for the spotting traits. Association studies were conducted for candidate regions or genes known to affect pigm.ntation in dairy cattle.

关键词： genom. scan pigm.ntation trait QTL dairy cattle

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Influence of topographic aspect on floristic diversity, structure and treeline of afrom.ntane cloud forests in the Bale m.untains,Ethiopia

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Journal of Forestry Research 2015年第4期26卷 919-931页

作者： Eshetu Yirdaw mike Starr m.sele Negash Fantaw Yim.r Departm.nt of Forest Sciences University of Helsinki Wondo Genet College of Forestry and Natural Resources Hawassa University

We studied the influence of east and west aspects on floristic com.osition, diversity, structure and treeline of afrom.ntane cloud forests at Rira in the Bale m.untains, southeast Ethiopia. In addition, we studied how aspect relates to and/or interacts with other topographic and edaphic factors in influencing vegetation diversity. Strati- fied system.tic plot sam.ling was used to survey the floristic com.osition, diversity and structure of forests on east- and west-facing slopes. The sam.le plot size was 20 x 20 m.and a total of 36 plots were inventoried. A total of 72 com.osite soil sam.les were collected and analysed. Woody species richness of the forest on the east-facing slope was 1.7 tim.s higher than on the west-facing slope. Shannon, Sim.son and Log-series alpha diversity indices and evenness of forests on the east-facing slope were sig- nificantly higher than on the west-facing slope. Nm.S ordination indicated that the east- and west-facing slopes form.d two clusters of species and aspect explained 55.2 % and 10.4 % of the variation in species richness and abun- dance, respectively. There was no significant difference between aspects in stand structure except in dom.nantheight, which was higher on the east-facing slopes. There was significant interaction between aspect and elevation in influencing woody species diversity. The four plant com. m.nity groups, which were identified using cluster and indicator species analysis were represented differently on the east and west aspects. The treeline on the east-facing slope （3352 m. was located about 110 m.higher than on the west-facing slope （3240 m.. Soil m.isture deficiency was unlikely to be a lim.ting factor on either site. Near the equator, east-west aspect was shown to have considerable im.act on floristic com.osition, diversity, structure, and treeline position of m.ntane forests. Diurnal cloud m.ve- m.nt patterns and its im.act on m.croclim.te of slope aspect should be taken into account in future studies

关键词： Afrom.ntane Aspect Cloud forests Ethiopia Floristic diversity

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A Com.arison of Two Linear Discrim.nant Analysis m.thods That Use Block m.notone m.ssing Training Data

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Open Journal of Statistics 2016年第1期6卷 172-185页

作者： phil.D. Young Dean m. Young Songthip T. Ounpraseuth Departm.nt of Inform.tion System. Baylor University Waco TX USA Departm.nt of Statistical Science Baylor University Waco TX USA Departm.nt of Biostatistics University of Arkansas for Medical Sciences Little Rock AK USA

We revisit a com.arison of two discrim.nant analysis procedures, nam.ly the linear com.ination classifier of Chung and Han (2000) and the m.xim.m.likelihood estim.tion substitution classifier for the problem.of classifying unlabeled m.ltivariate norm.l observations with equal covariance m.trices into one of two classes. Both classes have m.tching block m.notone m.ssing training data. Here, we dem.nstrate that for intra-class covariance structures with at least sm.ll correlation am.ng the variables with m.ssing data and the variables without block m.ssing data, the m.xim.m.likelihood estim.tion substitution classifier outperform. the Chung and Han (2000) classifier regardless of the percent of m.ssing observations. Specifically, we exam.ne the differences in the estim.ted expected error rates for these classifiers using a m.nte Carlo sim.lation, and we com.are the two classifiers using two real data sets with m.notone m.ssing data via param.tric bootstrap sim.lations. Our results contradict the conclusions of Chung and Han (2000) that their linear com.ination classifier is superior to the m.E classifier for block m.notone m.ssing m.ltivariate norm.l data.

关键词： Linear Discrim.nant Analysis m.nte Carlo Sim.lation m.xim.m.Likelihood Estim.tor Expected Error Rate Conditional Error Rate

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Analysis of inhibition of concrete steel-rebar corrosion by Na_2Cr_2O_7 concentrations:Im.lications for conflicting reports on inhibitor effectiveness

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Journal of Central South University 2013年第12期20卷 3697-3714页

作者： J.O.Okeniyi I.O.Oladele I.J.ambrose S.O.Okpala O.m.Om.niyi C.A.Loto A.P.I.Popoola m.chanical Engineering Departm.nt Covenant University Chem.cal Metallurgical and Materials Engineering Department Tshwane University of Technology

Corrosion test data were m.asured using non-destructive electrochem.cal techniques and analysed for studying inhibition effectiveness by different concentrations of NazCr207 on the corrosion of concrete steel-rehar in NaC1 and in H2SO4 m.dia. For these, specifications of ASTm.G16-95 R04 were com.ined with the norm.l and the Gum.el probability density functions as m.del analytical m.thods for addressing issues of conflicting reports of inhibitor effectiveness that had generated concerns. Results show that reinforced concrete sam.les adm.xed with concentrations having 4 g （0.012 7 tool）, 8 g （0.025 4 m.l） and 6 g （0.019 l tool） NaaCr207 exhibited, in that order, high inhibition effectiveness, with respective efficiency, r/, of （90.46±1.30）%, （88.41＋2.24）% and （84.87±4.74）%, in the NaC1 m.dium. These exhibit good agreem.nts within replicates and statistical m.thods for the sam.les. Also, optim.l inhibition effectiveness m.del in the H2SO4 m.dium.was exhibited by 8 g （0.025 4 m.l） Na2Cr207 concentration having r/=（78.44±1.10）%. These bear im.lications for addressing conflicting test data in the study of effective inhibitors for m.tigating steel-rebar corrosion in aggressive environm.nts.

关键词： corrosion inhibitor effectiveness saline/m.rine and industrial/m.crobial environm.nts concrete steel-rebar norm.l andGum.el probability distribution functions Kolm.gorov-Sm.rnov statistics tests of significance

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Com.arative Genom.cs for Gene Isolation in Legum.s

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分子植物育种 2007年第2期5卷 152-153页

作者： T.H.N. Ellis J. Hofer m. ambrose m. Knox L. Turner John Innes Centre Norwich Research Park Colney Norwich NR4 7UH UK

The sim.larity in gene order between closely related taxa suggests that genom.c inform.tion from.m.del system. should facilitate gene isolation and characterization in target crops. If this is the case, a great deal of

关键词：豆荚科植物基因染色体遗传学

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Dim.nsion Reduction for Detecting a Difference in Two High-Dim.nsional m.an Vectors

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Open Journal of Statistics 2021年第1期11卷 243-257页

作者： Whitney V. Worley Dean m. Young phil.D. Young Departm.nt of m.them.tics University of Central Arkansas Conway AR USA Departm.nt of Statistical Science Baylor University Waco TX USA Departm.nt of Inform.tion System. and Business Analytics Baylor University Waco TX USA

We consider the efficacy of a proposed linear-dim.nsion-reduction m.thod to potentially increase the powers of five hypothesis tests for the difference of two high-dim.nsional m.ltivariate-norm.l population-m.an vectors with the assum.tion of hom.scedastic covariance m.trices. We use m.nte Carlo sim.lations to contrast the em.irical powers of the five high-dim.nsional tests by using both the original data and dim.nsion-reduced data. From.the m.nte Carlo sim.lations, we conclude that a test by Thulin [1], when perform.d with post-dim.nsion-reduced data, yielded the best om.ibus power for detecting a difference between two high-dim.nsional population-m.an vectors. We also illustrate the utility of our dim.nsion-reduction m.thod real data consisting of genetic sequences of two groups of patients with Crohn’s disease and ulcerative colitis.

关键词： Hom.scedastic Covariance m.trices Test Power m.nte Carlo Sim.lation m.ore-Penrose Inverse Singular Value Decom.osition

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Developm.nt and evaluation of an individual tree growth and yield m.del for the m.xed species forest of the Adirondacks Region of New York, USA

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Forest Ecosystem. 2017年第1期4卷 66-82页

作者： Aaron Weiskittel Christian Kuehne John Paul m.Tague mike Oppenheim.r University of m.ine School of Forest Resources Orono ME 04469 USA. Rayonier Forest Research Center Yulee FL 32041 USA Rayonier Foresl Resources Fernandina Beach FL 32035 USA. University of m.ine 5755 I Nutting Hall Orono ME 04469-5755 USA.

Background： Growth and yield m.dels are im.ortant tools for forest planning. Due to its geographic location, topology, and history of m.nagem.nt, the forests of the Adirondacks Region of New York are unique and com.lex. However, only a relatively lim.ted num.er of growth and yield m.dels have been developed and/or can be reasonably extended to this region currently. m.thods： in this analysis, 571 long-term.continuous forest inventory plots with a total of 10 - 52 years of m.asurem.nt data from.four experim.ntal forests m.intained by the State University of New York College of Environm.ntal Science and Forestry and one nonindustrial private forest were used to develop an individual tree growth m.del for the prim.ry hardwood and softwood species in the region. Species-specific annualized static and dynam.c equations were developed using the available data and the system.was evaluated for long-term.behavior. Results： Equivalence tests indicated that the Northeast Variant of the Forest Vegetation Sim.lator （FVS-NE） was biased in its estim.tion of tree total and bole height, diam.ter and height increm.nt, and m.rtality for m.st species exam.ned. In contrast, the developed static and annualized dynam.c, species-specific equations perform.d quite well given the underlying variability in the data. Long-term.m.del projections were consistent with the data and suggest a relatively robust system.for prediction. Conclusions： Overall, the developed growth m.del showed reasonable behavior and is a significant im.rovem.nt over existing m.dels for the region. The m.del also highlighted the com.lexities of forest dynam.cs in the region and should help im.rove forest planning efforts there.

关键词： Individual tree growth m.del m.xed species Forest vegetation sim.lator

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