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Hodograph computation and bound estimation for rational B-spline curves

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Progress in Natural Science:Materials International 2007年第8期17卷 988-992页

作者： Xu Huixia~(1,2. Wang Guojin~(1,2.*) (1.institute of Computer Images and Graphics,zhejiang university,{2.,china 2.State Key Laboratory of CAD&CG,zhejiang university,{2.,china) institute of Computer Images and Graphics Zhejiang University Hangzhou 310027 China State Key Laboratory of CAD and CG Zhejiang University Hangzhou 310027 China

It is necessary to compute the derivative end estimate the bound of rational B-spline curves in design system,which has not been studied to *** improve the function of computer aided design (CAD) system,end to enhance the efficiency of different algo- rithms of rational B-spline curves,the representation of scaled hodograph and bound of derivative magnitude of uniform planar rational B- spline curves are derived by applying Dir function,which indicates the direction of Cartesian vector between homogeneous points,discrete B-spline theory end the formula of translating the product into a summation of B-spline *** an application of the result above, upper bound of parametric distance between any two points in a uniform planar rational B-spline curve is further presented.

关键词： computer aided design (CAD) rational B-spline discrete B-spline hodograph bound of derivative distance between two points

Differentiation of bone marrow mesenchymal stem cells induced by myo-cardial medium under hypoxic conditions

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Acta Pharmacologica Sinica 2006年第9期27卷 1153-1158页

作者： Xiao-jie XIE~1 Jian-an WANG~(1,3)Jiang CAO~2.Xing ZHANG~2.1 Division of Cardiology,the 2.d Affiliated Hospital,College of Medicine,zhejiang university hangzhou 310009,{2. 2.Clinical Research institute,Sir Run Run Shaw Hospital,College of Medicine,zhejiang university,hangzhou 310016,{2. Division of Cardiology the 2nd Affiliated Hospital College of Medicine Zhejiang University Hangzhou China Clinical Research institute Sir Run Run Shaw Hospital College of Medicine Zhejiang University Hangzhou China

Aim:To explore whether bone marrow mesenchymal stem cells(MSC)can differ-entiate into myocardial-like cells induced by myocardial medium,especially thehypoxia/reoxygenation-conditioned medium of ***:Myo-cardial cells obtained from neonatal Sprague-Dawley rat ventricles were isolatedand cultured in vitro and a hypoxia reoxygenation model was *** isolated from adult Sprague-Dawley rats were purified and then incubatedwith 3 different mediums:medium A-the conditioned medium of normalcardiomyocytes;medium B-the conditioned medium of cardiomyocytes afterhypoxia reoxygenation;and the control medium-ordinary *** expres-sions of the cardiac myosin heavy chain(MHC),troponin T(TnT)and connexin43 were investigated in the MSC after 2. h,48 h and 72.h cultivation,***:The MSC expressed MHC and TnT when incubated with the condi-tioned medium of cardiomyocytes after hypoxia reoxygenation,but did not ex-press connexin *** ofMHC,TnT and connexin 43 was detected in the MSCincubated with the conditioned medium of normal ***:The results indicate for the first time that myocardial medium for hypoxic precon-ditioning can induce MSC differentiation into myocardial-like cells.

关键词： bone marrow mesenchymal stem cells cardiomyocyte hypoxia reoxygenation

Synergy between Cucumber Mosaic Virus and Zucchini Yellow Mosaic Virus on Cucurbitaceae Hosts Tested by Real-time Reverse Transcription-Polymerase Chain Reaction

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Acta biochimica et biophysica Sinica 2007年第6期39卷 431-437页

作者： Rong ZENG~(1,2.), Qiansheng LIAO~(2.), Junli FENG~2. Dingjun LI~1, and Jishuang CHEN~(2.) 1 College of bio-Safety Science Technology, Hunan Agricultural university, Changsha 41012., {2., 2.institute of bioengineering, zhejiang Sci-Teeh university, hangzhou 310018, {2. College of bio-Safety Science Technology Human Agricultural UniversityChangsha 410128 China institute of bioengineering Zhejiang Sci-Tech UniversityHangzhou 310018 China

Cucumber mosaic virus (CMV) and zucchini yellow mosaic virus (ZYMV) are two principal viruses infecting cucurbitaceous crops, and their synergy has been repeatedly observed. In our present work, a real-time reverse transcription-polymerase chain reaction procedure was established to study the accumulation kinetics of these two viruses in single and combined infections at the molecular level. The accumulations of open reading frames (ORFs) for 1a, 2., 3a and coat protein (CP) of CMV and CP of ZYMV were tested. In the single infection, CMV-Fny ORFs accumulated to their maxima in cucumber or bottle gourd at 14 d post-inoculation (dpi), and gradually declined thereafter. ZYMV-SD CP ORF reached maximal accumulation at 14 and 2. dpi on cucumber and bottle gourd, respectively. However, when coinfected with CMV-Fny and ZYMV-SD, the maximal accumulation levels of all viral ORFs were delayed. CMV-Fny ORFs reached their maxima at 2. dpi on both hosts, and ZYMV-SD CP ORF reached maximal accumulation at 2. and 2. dpi on cucumber and bottle gourd, respectively. Generally, the accumulation levels of CMV-Fny ORFs in the co-infection were higher than those in the single infection, whereas the accumulation of ZYMV-SD CP ORF showed a reverse result.

关键词： cucumber mosaic virus genornic RNA real-time RT-PCR relative quantification synergy zucchini yellow mosaic virus

Multiple products of B-splines used in CAD system

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Progress in Natural Science:Materials International 2006年第4期16卷 425-430页

作者： XU Huixia and WANG Guojin institute of Images and Graphics, zhejiang university, {2., china State Key Laboratory of CAD&CG, zhejiang university, {2., china institute of Images and Graphics Zhejiang University Hangzhou 310027 China State Key Laboratory of CAD and CG Zhejiang University Hangzhou 310027 China

The function upgrade of computer aided design (CAD) system requested that the multiple product of B-spline functions should be represented as a linear combination of some suitable (usually higher-degree) B-splines. In this paper, we apply the theory of spline space and discrete B-splines to deduce the representation of the coefficients of all terms of the linear combination, which can be directly applied to software coding in system development.

关键词： computer aided design (CAD) NURBS Marsden’s identity.

Preparation and characterization of nitrogen-doped titanium dioxides

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Science china Chemistry 2007年第2期50卷 212-216页

作者： ZHU GuoPing1 & ZHOU KangGen2.1 environmental Science Research & Design institute of {2. Province,hangzhou 310007,china 2.Department of environmental Engineering,School of Metallurgical Science and Engineering,Central South university,Changsha 410083,china environmental Science Research & Design institute of {2. Province Hangzhou China Department of environmental Engineering School of Metallurgical Science and Engineering Central South University Changsha China

A type of high visible-light active titanium oxinitride(TiO2.xNx) powder was prepared by a simple proc-ess:the calcination of the hydrated titanium dioxide at the atmosphere of ammonia-argon using a tu-bular electric furnace at high temperatures. The hydrated titanium dioxide was synthesized as the precursor of TiO2.xNx using titanic acid as raw material,which came from sulfate technique of produc-ing titanium white. The effects of temperature and reaction time on the nitrogen content,grain size and crystal structure were studied. The visible-light activity and photocatalysis capability of the powder were also investigated.

关键词： nitrogen-doped titanium dioxides visible-light activity photocatalysis titanium oxinitride

Structural phase transition in nanostructured γ-Fe_2._3

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Chinese Science Bulletin 1997年第11期42卷 894-897页

作者： YE Xisheng, SHA Jian, SONG Hongqin, JIAO Zhengkuan, LU Guanglie, PENG Zifei and ZHANG Lide1. Department of Physics, zhejiang university, hangzhou 3.002., {2. 2. Central Laboratory, hangzhou university, hangzhou 3.002., {2. 3. institute of Solid State Physics, Chinese Academy of Sciences, Hefei 2.0031, {2. Department of Physics Zhejiang IJniversity Hangzhou China Central laboratory Hangzhou University Harigzhou China institute of Solid State Physics Chinese Academy of Sciences Hefei China

DUE to their specific physical,chemical and mechanical properties and large application proba-bility in many fields,nanostructured materials have been developing very fast in the recent *** stability is an important property of the *** interesting resultshave been obtained in the study of the thermal stability of nanostructured materials.

关键词： nanostructured γ-Fe2.3 differential thermal analysis (DTA) XRD microstructlire structural phase transition.

Phylogenetics and biogeography of eastern Asian–North American disjunct genus Pachysandra (Buxaceae) inferred from nucleotide sequences

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Journal of Systematics and Evolution 2009年第3期47卷 191-201页

作者： 1Zhihua JIAO 2.3Jianhua LI 1(School of Chemical and environmental Engineering, china {2. of Mining and Technology, Beijing 100083, china) 2.The Arnold Arboretum of Harvard {2., Cambridge, MA 02.38, USA) 3(Adjunct Faculty of College of Life Sciences, zhejiang university, hangzhou 3.002., china) (School of Chemical and environmental Engineering China University of Mining and Technology Beijing 100083 China) (The Arnold Arboretum of Harvard university Cambridge MA 02138 USA) (Adjunct Faculty of College of Life Sciences Zhejiang University Hangzhou 310029 China)

Pachysandra is an eastern Asian-North American disjunct genus with three species, two in eastern Asia (Pachysandra axillaris and Pachysandra terminalis) and one in eastern North America (Pachysandra procumbens). Although morphological and cytological studies suggest a close affinity of P. procumbens with P. axillaris, molecular data from nuclear and chloroplast DNA regions have provided conflicting signals. In this study, we tested previous phylogenetic hypotheses using sequences of nuclear ribosomal DNA internal transcribed spacers and chloroplast ndhF gene from multiple individuals of each of the three species. We also estimated the time of divergence between eastern Asia and eastern North America. Our results support the morphological and cytological conclusion that P. procumbens is more closely related to P. axillaris than to P. terminalis. The estimated time of divergence of P. axillaris and P. procumbens was 14.6±5.5 mya, consistent with estimates from many other eastern Asian-North American disjunct genera. The migration of Pachysandra populations from eastern Asia to North America might have occurred by way of the North Atlantic land bridge.

关键词： Buxaceae divergence time ndhF nrDNA ITS Pachysandra.

The three-dimensional structure of Infectious flacherie virus capsid determined by cryo-electron microscopy

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Science china(Life Sciences) 2009年第12期52卷 1186-1191页

作者： XIE Li1,4, ZHANG QinFen2., LU XingMeng3, DAI XinHong2. LI KunPeng2. HONG Jian1,4· & ZHOU XuePing11 institute of biotechnology, {2., hangzhou 3.002., china 2.State Key Laboratory of biocontrol, School of Life Sciences, Sun Yat-Sen university, Guangzhou 5102.5, china 3 College of Animal Sciences, {2., hangzhou 3.002., china 4 Center of Analysis and Measurement, {2., hangzhou 3.002., china institute of biotechnology Zhejiang University Hangzhou China Center of Analysis and Measurement Zhejiang University Hangzhou China State Key Laboratory of biocontrol School of Life Sciences Sun Yat-Sen University Guangzhou China College of Animal Sciences Zhejiang University Hangzhou China

Cryo-electron microscopy and image reconstruction were used to determine the three-dimensional structure of Infectious flacherie virus (IFV). 5047 particles were selected for the final reconstruction. The FSC curve showed that the resolution of this capsid structure was 18 ·. The structure is a psuedo T=3 (P=3) icosahedral capsid with a diameter of 302.4 · and a single shell thickness of 15 ·. The density map showed that IFV has a smooth surface without any prominent protrude or depression. Comparison of the IFV structure with those of the insect picorna-like virus-Cricket paralysis virus (CrPV)and human picornavirus-Human rhinovirus 14 (HRV 14) revealed that the IFV structure resembles the CrPV structure. The "Rossmann canyon" is absent in both IFV and CrPV particles. The polypeptide topology of IFV VP2. IFV VP3 was predicted and the subunit location at the capsid surface was further analyzed.

关键词： Infectious flacherie virus cryo-electron microscopy three-dimensional structure polypeptide folding

Two-dimensional electrophoresis analysis of proteomics based on image feature and mathematical morphology

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Science china Chemistry 2005年第4期48卷 361-367页

作者： SHEN Peng1,FAN Xiaohui2.ZENG Zhen2.& CHENG Yiyu2.1.The First Affiliated Hospital,College of Medicine,zhejiang university,hangzhou 310003,{2. 2.Pharmaceutical Informatics institute,zhejiang university,hangzhou 3.002.,{2. The First Affiliated Hospital College of Medicine Zhejiang University Hangzhou China Pharmaceutical Informatics institute Zhejiang University Hangzhou China

In this paper,a novel method to automatically detect protein spots on a two-dimensional (2.D) electrophoresis gel image is proposed to implement proteomics analysis of complex *** the basis of the identifying spots results based on color variation and spot size features,morphological feature is introduced as a new criterion to distinguish protein spots from non-protein ***-sharpening,edge-detecting and morphological feature extraction methods were consequently combined to detect protein spots on a 2.D electrophoresis gel image subject to strong *** proposed method was applied to detect the protein spots of proteomic gel images from *** cell,human kidney tissue and human *** results demonstrated that this method is more accurate and reliable than previous methods such as PDQuest 7.2.and ImageMaster 5.0 software for detecting protein spots on gel images with strong interferences.

关键词： proteomics, 2.dimensional electrophoresis, protein spot recognition, analytical chemistry for life, morphological feature, image recognition.