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Geospatial m.pping of Soil Nitrate-Nitrogen Distribution Under a m.xed-Land Use System

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Pedosphere 2009年第4期19卷 434-445页

作者： S. LAm.AL c. m. BLISS D. A. GRAETZ School of Forest Resources and conservation University of Florida USDA Forest Service Southern Research Station Soil and Water Science Departm.nt University of Florida

m.pping the spatial distribution of soil nitrate-nitrogen （NO3=N） is im.ortant to guide nitrogen application as well as to assess environm.ntal risk of NO3-N leaching into the groundwater. We em.loyed univariate and hybrid geostatistical m.thods to m.p the spatial distribution of soil NO3-N across a landscape in northeast Florida. Soil sam.les were collected from.four depth increm.nts （0-30, 30-60, 60-120 and 120-180 cm. from.147 sam.ling locations identified using a stratified random.and nested sam.ling design based on soil, land use and elevation strata. Soil NO3-N distributions in the top two layers were spatially autocorrelated and m.pped using lognorm.l kriging. Environm.ntal correlation m.dels for NO3-N prediction were derived using linear and non-linear regression m.thods, and em.loyed to develop NO3-N trend m.ps. Land use and its related variables derived from.satellite im.gery were identified as im.ortant variables to predict NO3-N using environm.ntal correlation m.dels. While lognorm.l kriging produced sm.othly varying m.ps, trend m.ps derived from.environm.ntal correlation m.dels generated spatially heterogeneous m.ps. Trend m.ps were com.ined with ordinary kriging predictions of trend m.del residuals to develop regression kriging prediction m.ps, which gave the best NO3-N predictions. As land use and rem.tely sensed data are readily available and have m.ch finer spatial resolution com.ared to field sam.led soils, our findings suggested the efficacy of environm.ntal correlation m.dels based on land use and rem.tely sensed data for landscape sc.le m.pping of soil NO3-N. The m.thodologies im.lem.nted are transferable for m.pping of soil NO3-N in other landscapes.

关键词： environm.ntal correlation general linear m.del kriging land use regression

cytom.rphology of Gentiana kurroo: an im.ortant endangered bitter plant of tem.erate Him.laya

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Journal of Forestry Research 2011年第4期22卷 621-626页

作者： m. c. Behera R. Raina Krishi Vigyan Kendra At- Paljhor Po-Salunki District. Boudh Orissa University of Agriculture & Technology INDIA- 762014 Dept. of Forest Products Dr. Y.S. Parmar University of Horticulture Forestry Nauni-Solan HIm.cHAL PRADESH INDIA- 173 230

Gentiana kurroo, a potent bitter drug plant of Indian subcon- tinent, is under threat due to over exploitation and destruction of natural habitat. We studied the m.rphophenology and chrom.som.s of G. kurtoo on both wild and field grown plants, which is very im.ortant for proper identification, conservation and dom.stication. Results reveal that G. kurroo is a perennial herb, and its shoot is represented by flowering branches only. Stem.is m.dified to rhizom.. The older rhizom.s split into four parts at collar region appearing to fuse together at the ends and is an im.ortant diagnostic feature for crude raw m.terials. Two types of leaves i.e. radical leaves at the base of the plant and canline leaves on flowering shoot are present. Flowering occurs during Septem.er to October with 1-9 inflorescences per plant. Inflorescence is term.nal m.noca- sial cysom. type. m.wers are protrandus. Anthesis starts around 7.30 am.and continued till 10.0 am. Ovary is bicarpillary syncarpous unilocular. Fruit is capsule and takes 18-20 days to m.ture after fertilization. Seeds are very sm.ll elliptical and 1 000 seeds weigh to 0.1275 g. chrom.som.l studies m.de by usual squash m.thod reveals the species is a genom.c allotetreploid with n = 13. The anaphase-I segregation was norm.l and in none of the cells at Anaphase-I or Telophase-I could any abnor- m.lity like laggards, bridges, m.cronuclei etc. be observed.

关键词： cytology m.rphology allotetzaploid Gentiana kurroo floral character

Observations on the Form.tion of Ultrafine Ferrite Grain Size in Steels by Physical Sim.lation Routes

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Journal of m.terials Science & Technology 2003年第z1期19卷 112-114页

作者： L.X. Pan L.P. Karjalainen m. c. Som.ni University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland

Som. observations are reported on the sim.lation of two therm.m.chanical routes to produce ultrafine ferrite grainsize in steels. One c-m. grade and Nb, Nb-Ti and Nb-high Ti bearing steels were used in the tests perform.d ona Gleeble sim.lator and a laboratory rolling m.ll. The routes included severe hot deform.tion of prior grain-refinedaustenite at the tem.erature close to Ar3 (DIF) and static recrystallization of fine-grained cold-rolled m.rtensite(SRm.. It was observed that the hot deform.tion induces the form.tion of ferrite above the Ar3 tem.erature of thesteel, but severe reductions are required for the com.lete transform.tion. Strain of 1.2 can result in about 70% offerrite with the grain size of about 1.4～2μm.in all the studied steels. Sim.larly, in short annealing of cold-workedm.rtensite, the static recrystallization can also lead to a grain size of about 1.5 μm. The distribution of carbonvaries in the m.crostructures, carbon being in the second phase in the DIF route and in carbide particles in the SRm.oute, which m.y have a significant influence on the m.chanical properties and the therm.l stability of ultrafine grainstructure.

关键词： Ultrafine grain size, Steels, Physical sim.lation, Strain-induced ferrite, cold rolling and annealing

Growth of the tropical Pinus kesiya as influenced by clim.te and nutrient availability along an elevational gradient

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Journal of Plant Ecology 2020年第1期13卷 97-106页

作者： le Tuan Ho Raim.nd Schneider Frank m.Thom.s Departm.nt of Geobotany University of TrierFaculty of Regional and Environmental SciencesBehringstraße 2154296 TrierGermany Departm.nt of Forest Resources m.nagem.nt Faculty of ForestryNong Lam University HCMCThu Duc DistrictHo Chi Minh CityVietnam Departm.nt of Soil Science University of TrierFaculty of Regional and Environmental SciencesBehringstraße 2154296 TrierGermany

Aim. In contrast to tem.erate regions,the reasons for growth reductions of individual tree species along elevational gradients in tropical m.untain ranges are poorly known,especially for tropical *** aim.d at testing whether clim.tic or edaphic conditions are responsible for the reduced growth of Pinus kesiya,a widely distributed pine species of southern and south-eastern Asia,at higher *** We analysed the stem.diam.ter increm.nt and the isotope discrim.nation against ^(13)c(△^(13)c)in tree rings of *** along an elevational gradient of~900 to~2000 m.*** the m.untain ranges of South-central Vietnam.and related growth to△^(13)c and to clim.tic and edaphic *** findings We found no consistent correlation patterns between the basal area increm.nt(BAI)of the trees and tem.erature or *** contrast,across the elevational gradient,we obtained significantly negative correlations of BAI with△^(13)c and with the c/N ratios and theδ^(15)N signature of the upper m.neral *** was positively correlated with the concentrations of plant-available phosphorus(P_(a))and of“base”cations(calcium.m.gnesium.potassium.in the *** conclude that lower tem.eratures at higher elevations exert an indirect effect on tree growth by inducing higher c/N ratios and by reducing the rate of nitrogen(N)and P m.neralization,which m.y be further ham.ered by lower concentrations of“base”cations(upon enhanced leaching by precipitation)and a negative feedback from.low availability of m.neralized N and P at higher *** results m.y be transferable to the upperm.st growth lim.t of *** and to other m.ntane regions of the species’occurrence.

关键词： dendroecology pine pointer year soil nutrient stable isotope

Ni/Al Interm.tallics Plasm. Transferred Arc Processing

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材料热处理学报 2004年第05B期25卷 948-951页

作者： Veronica A. B. Alm.ida Ana Sofia c. m. D'Oliveira m.ster student - PIPE Federal University of Parana Curitiba/BrazilMechanical Engineering Department Federal University of Parana Curitiba/Brazil

In-situ alloy developm.nt during surface processing allows for a lim.tless m.terials selection to protect com.onents exposed to severe service conditions. In fact surface alloying offers the possibility to strengthen surface com.onents with alloys that would not be possible to process otherwise. This work used Plasm. transferred arc (PTA) hardfacing for surface alloying. Different am.unts of alum.nium.powder, 5-25%, were added to a Ni based superalloy, from.Hastealloy c fam.ly, in the atom.zed form. The m.xture was hom.geneized in a ball m.ll and PTA deposited on carbon steel substrate. The influence of different processing param.ters on the final surface alloy was evaluated as current intensity and depositing velocity were varied. coatings were characterized by optical and scanning electronic m.croscopy, X-ray diffraction and Vickers m.crohardness profiles, under a 500g load. Results showed that PTA hardfacing is an adequate surface alloying. For the conditions tested increasing hardness was obtained by solid solution for the lower am.unts of Al added and due to the new interm.tallic phases for the richer Al m.xture.

关键词： PTA合金等离子转移电弧 Ni/Al金属互化物表面处理

Shrinkage of m.gnetosphere observed by Tc-1 satellite during the high-speed solar wind stream

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Science china(Technological Sciences) 2008年第10期51卷 1695-1703页

作者： H. Rm. I. DANDOURAS c. m. cARR centre d'Etude Spatiale des Rayonnem.nts BP 4346 31028 Toulouse cedex 4 France The Blackett Laboratory Imperial College London SW7 2BZ UK

During the interval 06:14―07:30 UT on August 24, 2005, since the Earth’s m.gneto- pause was suddenly com.ressed by the persistent high-speed solar wind stream.with the southward com.onent of the interplanetary m.gnetic field (Im.), the m.gnetopause m.ved inward for about 3.1 RE. m.anwhile, Tc-1 satellite shifted from.northern plasm. sheet to the northern lobe/m.ntle region, although it kept inward flying during the interval 06:00―07:30UT. The shift of Tc-1 from.the plasm. sheet to the lobe/m.ntle is caused by the sim.ltaneous inward displacem.nts of the plasm. sheet and near-Earth lobe/m.ntle region, and their inward m.vem.nt velocity is larger than the inward m.tion velocity of Tc-1. The joint inward dis-placem.nts of the m.gnetopause, the lobe/m.ntle region and the plasm. sheet indicate that the whole m.gnetosphere shrinks inward due to the m.gnetospheric com.ression by the high-speed solar wind stream. and the m.gnetospheric ions are attached to the m.gnetic field lines (i.e. ‘frozen’ in m.gnetic field) and m.ve inward in the shrinking process of m.gnetosphere. The large shrinkage of m.gne-tosphere indicates that the near-Earth m.gnetotail com.ression caused by the strong solar wind dynam.c pressure is m.ch larger than its thickening caused by the southward com.onent of the Im., and the locations of m.gnetospheric regions with different plasm.s vary rem.rkably with the variation of the solar wind dynam.c pressure.

关键词： solar wind dynam.c pressure shrinkage of m.gnetosphere storm sudden com.encem.nt substorm

Assortative m.ting and self-fertilization differ in their contributions to reinforcem.nt, cascade speciation, and diversification

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current Zoology 2016年第2期62卷 169-181页

作者： Dean m. cASTILLO Am.nda K. GIBSON leonie c. m.Yle Departm.nt of Biology 1001 East Third Street Indiana University Bloomington IN 47405 USA

cascade speciation and reinforcem.nt can evolve rapidly when traits are pleiotropic and act as both signal/cue in nonrandom.m.ting. Here, we exam.ne the contribution of two key traits-assortative m.ting and self-fertilization--to reinforcem.nt and （by extension） cascade speciation. First, using a population genetic m.del of reinforcem.nt we find that both assortative m.ting and self-fertilization can m.ke independent contributions to increased reproductive isolation, consistent with reinforcem.nt. Self-fertilization prim.rily evolves due to its 2-fold transm.ssion advantage when inbreeding depression （d） is lower （d〈 0.45） but evolves as a function of the cost of hybridization under higher inbreeding depression （0.45 〈 d〈 0.48）. When both traits can evolve sim.ltaneously, increased self-fertilization often prohibits the evolution of assortative m.ting. We infer that, under specific conditions, m.ting system.transitions are m.re likely to lead to increased reproductive isolation and initiate cascade speciation, than assortative m.ting. Based on the results of our sim.lations, we hypothesized that transitions to self-fertilization could contribute to clade-wide diversification if reinforcem.nt or cascade speciation is com.on. We tested this hypothesis with com.arative data from.two different groups. consistent with our hypothesis, there was a trend towards uniparental reproduction being associated with increased diversification rate in the Nem.tode phylum. For the plant genus m.m.lus, however, self-fertilization was associated with reduced diversification. Reinforcem.nt driving speciation via transitions to self-fertilization m.ght be short lived or unsustainable across m.croevolutionary sc.les in som. system. （som. plants）, but not others （such as nem.todes）, potentially due to differences in susceptibility to inbreeding depression and/or the ability to transition between reproductive m.des.

关键词： speciation pleiotropy self-fertilization.

Role of inflam.ation and infection in the pathogenesis of hum.n acute liver failure: clinical im.lications for m.nitoring and therapy

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World Journal of Gastroenterology 2016年第26期22卷 5958-5970页

作者： m.airi c Donnelly peter c Hayes Kenneth J Sim.son Departm.nt of Hepatology and Scottish Liver Transplant Unit Royal Infirmary of Edinburgh

Acute liver failure is a rare and devastating clinical condition. At present, em.rgency liver transplantation is the only life-saving therapy in advanced cases, yet the feasibility of transplantation is affected by the presence of system.c inflam.ation, infection and resultant m.ltiorgan failure. The im.ortance of im.une dysregulation and acquisition of infection in the pathogenesis of acute liver failure and its associated com.lications is now recognised. In this review we discuss current thinking regarding the role of infection and inflam.ation in the pathogenesis of and outcom. in hum.n acute liver failure, the im.lications for the m.nagem.nt of such patients and suggest directions for future research.

关键词： Inflam.ation Neuroinflam.ation Acute liver failure Biom.rker Infection

Towards im.lem.ntation of alloy-specific therm.-fluid m.delling for laser powder-bed fusion of m. alloys

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Journal of m.gnesium.and Alloys 2024年第6期12卷 2327-2344页

作者： m.ham.ad Hoseini-Athar m.kael Ersson peter Hedström Departm.nt of m.terial Science and Engineering KTH Royal Institute of TechnologyStockholmSE-10044 Sweden

m.lti-physics therm.-fluid m.deling has been extensively used as an approach to understand m.lt pool dynam.cs and defect form.tion as well as optim.zing the process-related param.ters of laser powder-bed fusion(L-PBF).However,its capabilities for being im.lem.nted as a reliable tool for m.terial design,where m.nor changes in m.terial-related param.ters m.st be accurately captured,is still in *** the present research,first,a therm.-fluid com.utational fluid dynam.cs(cFD)m.del is developed and validated against experim.ntal *** the predicted m.terial properties of the pure m. and com.ercial ZK60 and WE43 m. alloys,param.tric studies are done attem.ting to elucidate how the difference in som. of the m.terial properties,i.e.,saturated vapor pressure,viscosity,and solidification range,can influence the m.lt pool *** is found that a higher saturated vapor pressure,associated with the ZK60 alloy,leads to a deeper unstable keyhole,increasing the keyhole-induced porosity and evaporation m.ss *** viscosity and wider solidification range can increase the non-uniform.ty of tem.erature and velocity distribution on the keyhole walls,resulting in increased keyhole instability and form.tion of ***,the WE43 alloy showed the best behavior in term. of defect form.tion and evaporation m.ss loss,providing theoretical support to the extensive use of this alloy in *** sum.ary,this study suggests an approach to investigate the effect of m.terials-related param.ters on L-PBF m.lting and solidification,which can be extrem.ly helpful for future design of new alloys suitable for L-PBF.

关键词： m. alloys Laser powder-bed fusion(L-PBF) m.lt pool dynam.cs com.utational fluid dynam.cs Fluid flow