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Maize ZmFDR3.localized in chloroplasts is involved in iron transport

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Science China(Life sciences) 2009年第9期52卷 864-871页

作者： HAN JianHui1,SONG XiuFang1,LI Peng1,YANG HuiJun2 & YIN LiPing1 1 College of Life Science,Capital Normal university,beijing 100048,China 2 Department of Biological sciences,university of South Carolina,Columbia,SC 29208,USA College of Life Science Capital Normal University Beijing China Department of Biological sciences University of South Carolina Columbia USA

Iron is an essential nutrient for plant metabolism such that Fe-limited plants display chlorosis and suffer from reduced photosynthetic efficiency. Differential display previously identified genes whose expression was elevated in Fe-deficient maize roots. Here,we describe the functional characterization of one of the genes identified in the screen,ZmFDR3.(Zea maize Fe-deficiency-related). Heterologous functional complementation assays using a yeast iron uptake mutant showed that ZmFDR3.functions in iron transport. ZmFDR3.contains a domain found in FliN-proteins of the type III secretion system and is predicted to localize to the thylakoid of plastids. Fluorescence immunocytochemistry showed that ZmFDR3.is localized in the plastids of roots,stems and leaves,with high expression found in guard cell chloroplasts. Transgenic tobacco expressing a 3.S-ZmFDR3.construct contains elevated iron content,displays well arranged thylakoid membranes and has photosynthetic indices that are higher than those of the wild type. Together,these results suggest that ZmFDR3.functions in chloroplast iron transport.

关键词： ZmFDR3 iron transport iron content chloroplasts

POSITIVE PERIODIC SOLUTION TO SECOND-ORDER NEUTRAL FUNCTIONAL DIFFERENTIAL EQUATION WITH MIXED DELAY

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Annals of Differential Equations 2012年第2期28卷 194-201页

作者： Yaping Ma, Zongfu Zhou , Jianzhong Xu (school of mathematical sciences, Anhui {3., Hefei 23.03.)

We discuss two types of second-order neutral functional differential equations with mixed delay in this paper. By applying Krasnoselskii’s fixed-point theorem, some results about the existence of positive periodic so... 详细信息

关键词： Krasnoselskii’s fixed-point theorem neutral functional differential equations positive periodic solution

Numerical Study of the Forming Process of High Frequency Welded Pipe

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Journal of Shanghai Jiaotong university(Science) 2010年第2期15卷 236-240页

作者：李建新谢里阳王军杰熊建辉 school of Mechanical Engineering Northeastern University(Shenyang) Baosteel Co. Ltd. school of Mechanical Engineering Shanghai Jiaotong University

The roll forming process is applied to the manufacturing of high frequency welded (HFW) pipes,section steels,etc. In this paper,the roll forming process of the HFW pipe is simulated with the finite element method (FEM). A user-defined material routine of the commercial finite element code ABAQUS/Explicit is developed,and the mixed hardening constitution model is realized through the user-defined material routine. Based on the mixed hardening constitutive equation,the numerical simulation of roll forming process of HFW pipe is performed. The evolutions of equivalent stress and strain are analyzed,and the calculated results are also compared between different hardening models. The results show that the different material hardening models have some important effects on the variation of equivalent stress and strain of strip steel during the simulation of the roll forming process.

关键词： numerical simulation mixed hardening model high frequency welded pipe cage roll forming userdefined material routine

Decoupling of surface and subsurface sutures in the Dabie orogen and a continent-collisional lithospheric-wedging model: Sr-Nd-Pb isotopic evidences of Mesozoic igneous rocks in eastern China

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Chinese Science Bulletin 2003年第8期48卷 831-838页

作者： LI Shuguang & YANG Wei school of Earth and Space sciences, university of Science and Tech-nology of China, Hefei 23.026, China school of Earth and Space sciences University of Science and Technology of China Hefei 230026 China

There are significant differences of Nd and Pbisotopic compositions between Mesozoic mafic igneous rocks from the North China Block (NCB) and the South ChinaBlock (SCB). Mesozoic mantle-derived igneous rocks fromthe North China Block have very low e Nd values (-15 to -21), and 206Pb/204Pb ratios ( -10 and 206Pb/204Pb > 18.3. The verylow e Nd values (-16 to -20) and 206Pb/204Pb ratios (3. of the early Cretaceous mafic-ultramafic intrusions developedin the north part of the Dabie orogen (NDZ) suggest that the deep lithosphere underneath the NDZ belongs to the NCBbut not the SCB. Therefore, although the surface suture be-tween the NCB and SCB is located on the north side of theNDZ, the subsurface suture between the NCB and SCBshould be located to the south side of the NDZ. This is con-sistent with the previous suggestion that the subsurface su-ture in the Sulu terrane east of the Tanlu fault was the south displacement, but contradictory to northward continentalsubduction of the SCB. A continent-collisional lithospheric-wedging model can interpret the decoupling of the surface and subsurface sutures in the Dabie-Sulu orogen. After slabbreak-off, the continuing convergence of two continental blocks must increase the compression force acting on the suture zone, which might induce the lithosphere splitting of SCB. Thus, the lower crust and lithospheric mantle on thesouth margin of the NCB can wedge into the north margin of the lithosphere of the SCB along the Dabie-Sulu collisionzone. This process caused the overthrust of the mid-upper continental crust with exhumed ultrahigh pressure meta-morphic (UHPM) rocks and underthrust of the deep litho-sphere of the SCB. It could be an important mechanism re-sponsible for the second rapid cooling and uplifting of theUHPM rocks and lithospheric delamination as well as thecorresponding magmatism in Jurassic in the Dabie *** southward movement of subsurface suture

关键词：大别造山带同位素中生代火成岩中国

Natural eco-environmental evaluation of eastern Qinghai-Tibet Plateau using RS and GIS

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Journal of Geographical sciences 2002年第3期12卷 283-288页

作者： YANG Shengtian, LIU Changming, YANG Zhifeng, SUNRui, ZHOU Xiaodong(1. Inst. of Environmental sciences, beijing Normal university, beijing 100875, China 2. Dept. of Resources and Environmental Science, beijing Normal university, beijing 100875,China) Inst. of Environmental sciences Beijing Normal University 北京 100875 Dept. of Resources and Environmental Science Beijing Normal University 北京 100875

The impact of interbasin water transfer on environment is very significant. The affected area of the west route scheme of the South to North Water Transfer Project in China (SNWT) is located in the eastern Tibetan Plateau, where the altitude is high with frigid eco-environment. In this article, remote sensing and GIS are applied to analyze the natural environment and the natural environment index is established to express the natural conditions of the study area. After the natural environment index is divided into four grades and the features of each grade are analysed, some results are obtained for reference in environmental assessment of the west route of SNWT.

关键词： Qinghai-Tibet Plateau environmental assessment remote sensing GIS

Molecular mechanisms of adenosine-induced apoptosis in human HepG2 cells

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Acta Pharmacologica Sinica 2006年第4期27卷 477-484页

作者： Ling-fei WU~(2,4) Guo-ping LI~2 Jia-lin FENG~3.Ze-jin PU~2 ~2Department of Gastroenterology:~3.epartment of Information,Second Affiliated Hospital,Shantou university Medical College,Shantou 515041.China Department of Gastroenterology Second Affiliated Hospital Shantou University Medical College Shantou China Department of Information Second Affiliated Hospital Shantou University Medical College Shantou China

Aim:To investigate effects of adenosine on cell proliferation and apoptosis inhuman HepG2 ***:HepG2 cells were incubated in the presence ofadenosine(0.1-5 mmol/L)for 12-48 h,and the effect of adenosine on cell prolifera-tion was evaluated by using 3.(4,5-dimethyl-2-yl)-2,5-diphenyl-2H-tetrazolium bro-mide(MTT)*** 3.3.2 fluorescent staining,dUTP-fluoresceinisothiocyanate(FITC)fluorescence and flow cytometric analysis techniques wereused to observe cell *** effects of adenosine receptor(A1,A2a,A3.nd nonspecific receptor)antagonists(8-cpt,DMPX,MRS 1191,and theophylline)and an adenosine transporter protein inhibitor(dipyridamole)on adenosine-in-duced cell apoptosis were *** membrane potential was ana-lyzed using DePsipher fluorescent staining,and caspase activity was detectedusing a Fluorometric assay kit and a fluorescence microplate ***:Adenosine significantly reduced cell viability in a dose-and *** cytotoxicity of adenosine was related to the induction of cell *** adenosine receptor antagonists had no effect on cell ***,dipyridamole significantly reduced the percentage of adenosine-induced apoptoticcells from 27.3. to 7.1%(P3.mmol/L adenosineincreased caspase-3.activity 3.5-fold;dipyridamole markedly decreased caspase-3.activity 1.6-fold,and decreased apoptotic cell *** HepG2 cells weretreated with 3.mmol/L adenosine,mitochondrial membrane potential and theactivity of caspase-8 or-9 remained ***:Our results suggestthat adenosine-induced apoptosis in HepG2 cells is related to intracellular eventsrsther than cell surface receptors,and that a caspase-3.cascade activation isrequired,which is not mediated via a mitochondrial pathway.

关键词： adenosins adenosine receptor apoptosis caspase HepG2 mitochondria

Fast algorithm based on triplet Markov fields for unsupervised multi-class segmentation of SAR images

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Science China(Information sciences) 2011年第7期54卷 1524-1533页

作者： WU Yan 1,WANG Xin 1,XIAO Ping 2,GAN Lu 1,LIU ChunYan 1 & LI Ming 3.1 school of Electronics Engineering,Xidian university,Xi’an 710071,China 2 Shaanxi Bureau of Surveying & Mapping,Xi’an 710054,China 3.National Key Laboratory of Radar Signal Processing,Xidian university,Xi’an 710071,China school of Electronics Engineering Xidian University Xi’an China Shaanxi Bureau of Surveying & Mapping Xi’an China National Key Laboratory of Radar Signal Processing Xidian University Xi’an China

Non-Gaussian triplet Markov fields (TMF) model is suitable for dealing with multi-class segmentation of non-stationary and non-Gaussian synthetic aperture radar (SAR) *** the complexity of the model and algorithm,as well as the requirement of real-time,and robust and efficient processing of SAR images,a fast algorithm based on TMF for unsupervised multi-class segmentation of SAR images is proposed in this *** the speckle noise in SAR images,numerical characteristic,threshold selection and QuadTree decomposition criterion are researched *** the new method,a SAR image can quickly be mapped into an edge-based pixon-representation,which results in a coarse decomposition in smooth regions,and a fine decomposition in *** by combining TMF model with the pixon-representation of SAR image,a new potential energy function of TMF based on pixon-representation is ***,the segmentation is finished by Bayesian maximum posterior mode (MPM).The effectiveness of the fast TMF algorithm is demonstrated by applying it to simulated data and real SAR images.

关键词： pixon-representation of SAR image QuadTree decomposition new potential energy function triplet Markov fields multi-class segmentation

PREPARATION AND CHARACTERIZATION OF DOXORUBICIN-LOADED MAGNETIC ANTICANCER NANOPARTICLES

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Chinese Journal of Reactive Polymers 2007年第Z1期 96-100页

作者： LV Fengjiao1 LIN Huaxiang2 CHEN Xiaogeng3.XU Xiaoping2 1. school of Chemistry and life sciences, Quanzhou Normal university Quanzhou,3.2000, China 2. school of Chemistry and Chemical Engineering, Fuzhou university, Fuzhou 3.0002, China 3. Fujian Provincial Hospital Fuzhou 3.0000, China

Doxorubicin(ADM)-loaded magnetic anticancer nanoparticles,using Fe3.4 as core, doxorubicin as model drug and polyvinylpyrrolidone (PVP) as matrix, were prepared by inverse emulsion polymerization. The experimental results showed that the average diameter of Fe3.4 particles was 19.8nm. The X-ray diffraction indicated that the prepared Fe3.4 particle was pure cubic Fe3.4. The results obtained by SEM showed the magnetic nanoparticles under optimal operating condition had a smooth spherical surface , LLS showed an average size of 78.7nm. And IR results demonstrated that they consisted of ADM, PVP and Fe3.4.

关键词： Magnetic nanoparticles Polyvinylpyrrolidone Inverse emulsion polymerization.

Preconcentration and determination of trace copper(II) in natural water using silica gel modified with 1-(2-pyridylazo)-2-naphthol

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Journal of Environmental sciences 1989年第1期1卷 121-124页

作者： Tong Shenyang, Liu Feng, Li Kean Department of Chemistry,peking university,beijing China

Trace copper (II) in water can be preconcentrated using silica gel modified with 1-(2-pyridylazo)-2-naphthol (PAN) and be determined spectrophotometri-cally. The conditions for the preconcentration were studied. The method was applied to both artificial and natural water samples and the results suggest that copper (II) of ppb level in water can be measured accurately after the preconcentration.

关键词： PAN silica gel copper preconcentration.