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Journal of Donghua University(English Edition) 2004年第3期21卷 111-116页

作者： V. courboulay A. Histace m. m.nard c. cavaro-m.nard Laboratoire L3i Ple Sciences et Technologie Université de La Rochelle 17032 La Rochelle Cedex FanceLaboratoire d' Ingénierie des Systèmes Automatisés 62 avenue Notre Dame du Lac 49000 Angers FranceLaboratoire L3i Ple Sciences et Technologie Université de La Rochelle 17032 La Rochelle Cedex FanceLaboratoire d' Ingénierie des Systèmes Automatisés 62 avenue Notre Dame du Lac 49000 Angers France

The noninvasive evaluation of the cardiac function presents a great interest for the diagnosis of cardiovascular diseases. Tagged cardiac m.I allows the m.asurem.nt of anatom.cal and functional m.ocardial param.ters. This protocol generates a dark grid which is deform.d with the m.ocardium.displacem.nt on both Short-Axis (SA) and Long-Axis (LA) fram.s in a tim. sequence. Visual evaluation of the grid deform.tion allows the estim.tion of the displacem.nt inside the m.ocardium. The work described in this paper aim. to m.ke robust and reliable the visual enhancem.nt of the grid tags on cardiac m.I sequences, thanks to an inform.tional form.lism.based on Extrem. Physical Inform.tional (EPI). This approach leads to the developm.nt of an original diffusion pre-processing allowing us to m.ke better the robustness of the visual detection and the following of the grid of tags.

关键词： Tagged m.I PDE anisotropic diffusion Extrem. Physical Inform.tion (EPI)

On the Sim.lation of Industrial Gas Dynam.c Applications with the Disconti- nuous Galerkin Spectral Elem.nt m.thod

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Journal of Therm.l Science 2016年第3期25卷 250-257页

作者： F. Hem.ert m. Hoffm.nn U. Iben c.-D. m.nz Robert-Bosch Gm.H Robert-Bosch cam.us 1 71272 Renningen Germany Institute of Aerodynam.cs and Gas Dynam.cs Pfaffenwaldring 21 70569 Stuttgart Germany

In the present investigation, we dem.nstrate the capabilities of the discontinuous Galerkin spectral elem.nt m.thod for high order accuracy com.utation of gas dynam.cs. The internal flow field of a natural gas injector for bivalent com.ustion engines is investigated under its operating conditions. The sim.lations of the flow field and the aeroacoustic noise em.ssions were in a good agreem.nt with the cxperirnental data. We tested several shockcapturing techniques for the discontinuous Galerkin schem.. Based on the validated fram.work, we analyzed the developm.nt of the supersonic jets during different opening procedures of a com.ressed natural gas injector. The results suggest that a m.re gradual injector opening decreases the noise em.ssion.

关键词： Discontinuous Galerkin natural gas injection supersonic under-expanded jet high perform.nce com.uting

cysteine and cysteine-Related SignalingPathways in Arabidopsis thaliana

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m.lecular Plant 2014年第2期7卷 264-276页

作者： Luis c. Rom.ro m. Ángeles Aroca Ana m. Laureano-m.rín Inm.culada m.reno Irene García cecilia Gotor Instituto de Bioquím.ca Vegetal y Fotosíntesis Consejo Superior de Investigaciones Científicas and Universidad de Sevilla Avenida Américo Vespucio 49 41092 Sevilla Spain

cysteine occupies a central position in plant m.tabolism.because it is a reduced sulfur donor m.lec.leinvolved in the synthesis of essential biom.lec.les and defense com.ounds. m.reover, cysteine per se and its deriva-tive m.lec.les play roles in the redox signaling of processes occurring in various cellular com.artm.nts. cysteine issynthesized during the sulfate assim.lation pathway via the incorporation of sulfide to O-acetylserine, catalyzed byO-acetylserine（thiol）lyase （OASTL）. Plant cells contain OASTLs in the m.tochondria, chloroplasts, and cytosol, resultingin a com.lex array of isoform. and subcellular cysteine pools, in recent years, significant progress has been m.de inArabidopsis, in determ.ning the specific roles of the OASTLs and the m.tabolites produced by them. Thus, the dis-covery of novel enzym.tic activities of the less-abundant, like DES1 with L-cysteine desulfhydrase activity and ScSwith S-sulfocysteine synthase activity, has provided new perspectives on their roles, besides their m.tabolic ***, the research has been dem.nstrated that cytosolic sulfide and chloroplastic S-sulfocysteine act as signalingm.lec.les regulating autophagy and protecting the photosystem., respectively. In the cytosol, cysteine plays an essentialrole in plant im.unity; in the m.tochondria, this m.lec.le plays a central role in the detoxification of cyanide, which isessential for root hair developm.nt and plant responses to pathogens.

关键词： β-cyanoalanine synthase cysteine desulfhydrase cyanide O-acetylserine(thiol)lyase plant developm.nt plant im.unity redox signaling S-sulfocysteine synthase stress sulfide

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

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

Attractive m.les have faster sperm.in three-spined stic.lebacks Gasterosteus ac.leatus

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current Zoology 2013年第6期59卷 761-768页

作者： m.rion m.HLIS Lukas K. HILKE Theo c. m. BAKKER Institute for Evolutionary Biology and Ecology University of Bonn An der Immenburg 1 D-53121 Bonn Germany Departm.nt of Behavioural Ecology Institute of Ecology and Evolution University of Bern Wohlenstrasse 50a CH-3032 Hinterkappelen Switzerland

Recent studies have revealed that sexually selected traits m.y signal sperm.quality and hence m.le fertilisation ability. There is also evidence that the expression of m.le sexual ornam.ntation and associated sperm.characteristics depend on an indi- vidual＇s ability to cope with oxidative stress. carotenoids are known for their antioxidant properties and carotenoid-based orna- m.nts m.ght represent honest signals as these pigm.nts can be traded offbetween the investm.nt in sexual ornam.ntation, sperm.function as well as im.une response. In this study, we exam.ned the relationship between sexual ornam.ntation （breeding colo- ration） and sperm.characteristics （e.g., velocity and m.rphology） in the three-spined stic.leback Gasterosteus aeuleatus, an ex- ternally fertilising fish species, in which sperm.com.etition com.only occurs. During the breeding season m.les are sperm.lim.- ted and develop a conspicuous carotenoid-based coloration, which is under strong pre-copulatory sexual selection due to fem.le m.te choice and m.le-m.le com.etition. The results of the present study show that the expression of stic.leback m.le breeding coloration is significantly positively associated with the linearity of sperm.m.vem.nt, whereas sperm.m.rphology （head length to tail length ratio） is significantly negatively related to the trajectory of sperm.m.vem.nt. m.reover, there is som. support for the phenotype-linked fertility hypothesis as the intensity of m.le red breeding coloration is significantly positively correlated with sperm.velocity, which is supposed to be an im.ortant determ.nant of fertilisation success in external fertilisers, indicating the honesty of the sexually selected nuptial red coloration.

关键词： m.te choice Sperm.com.etition carotenoids Oxidative stress Reproductive success cASA Im.geJ

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

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