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Molecular Cloning of a Cytosolic G6PDH Gene from Populus Suaveolens and Its Expression to Improve the Cold Resistance of Tobacco Plants

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冰川冻土 2009年第6期31卷 1178-1185页

作者： LIN Yuan-zhen1,2.GUO Hai3,ZHANG Zhi-yi2.LIN Shan-zhi2.(1. College of Forestry,South china Agricultural university,Guangzhou Guangdong 510642.{2. 2. Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental Plants,MOE,Beijing Forestry university,Beijing 100083,{2. 3. Plant Materials center for Soil and Water Conservation,Ministry of Water Resources,Beijing100038,{2.) College of Forestry South China Agricultural University Guangdong Guangzhou 510642 Plant Materials center for Soil and Water Conservation Ministry of Water ResourcesChina Beijing 100038 Beijing Forestry university Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental PlantsMOE Beijing 100083 Beijing Forestry university Key Laboratory for Genetics and Breeding in Forest Trees and Ornamental PlantsMOE Beijing 100083

Glucose-6-phosphate dehydrogenase (G6PDH,EC 1.***.1.49) is the first and main regulated enzyme of oxidative pentose phosphate pathway (OPPP),catalyzing the conversion of glucose-6-phosphate to 6-phospho-gluconolactone and playing important roles in the growth and development of plants. It is preciously reported that the enhancement of freezing resistance of Populus suaveolenscuttings is clear related to the distinct increase in cytosolic G6PDH activity. Here,a 1697 bp cDNA fragment (PsG6PDH) is amplified by RT-PCR from cold-induced total RNA of the freezing-tolerant P. suaveolens. A sequence analysis showed that PsG6PDH coding region had 1 530 bp and encoded 510 predicted amino acid residues. Genomic Southern analysis revealed that the isoform is encoded by a few copies of the gene in the poplar genome. The cloned gene PsG6PDHis cloned into binary vector pBI12. and used to transform tobacco. PCR and Southern blotting results verified integration of this gene into the genome of tobacco. Moreover,cold treatment experiments and membrane defense enzymeactivity analysis confirmed that overexpression of the PsG6PDHgene could enhance the tolerance to cold or frigid stresses in transgenic plants.

关键词： Populus suaveolens glucose-6-phosphate dehydrogenase cold resistance gene engineering

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Bioreducible unimolecular micelles based on amphiphilic multiarm hyperbranched copolymers for triggered drug release

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Science china Chemistry 2010年第12期53卷 2497-2508页

作者： PANG Yan 1,LIU JinYao 1,SU Yue 1,ZHU BangShang 2.HUANG Wei 1,ZHOU YongFeng 1,ZHU XinYuan 1,2.& YAN DeYue 1 1 School of Chemistry and Chemical Engineering,State Key Laboratory of Metal Matrix Composites,Shanghai Jiao Tong university,Shanghai 2.02.0,china 2.Instrumental {2. center,Shanghai Jiao Tong university,Shanghai 2.02.0,china 1. School of Chemistry and Chemical Engineering State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Shanghai 200240 China2. Instrumental Analysis Center Shanghai Jiao Tong University Shanghai 200240 China

A novel type of bioreducible amphiphilic multiarm hyperbranched copolymer (H40-star-PLA-SS-PEG) based on Boltorn H40 core,poly(L-lactide) (PLA) inner-shell,and poly(ethylene glycol) (PEG) outer-shell with disulfide-linkages between the hydrophobic and hydrophilic moieties was developed as unimolecular micelles for controlled drug release triggered by *** obtained H40-star-PLA-SS-PEG was characterized in detail by nuclear magnetic resonance (NMR),Fourier transform infrared (FTIR),gel permeation chromatography (GPC),differential scanning calorimeter (DSC),and thermal gravimetric analysis (TGA).Transmission electron microscopy (TEM) and dynamic light scattering (DLS) analyses suggested that H40-star-PLA-SS-PEG formed stable unimolecular micelles in aqueous solution with an average diameter of 19 ***,these micelles aggregated into large particles rapidly in response to 10 mM dithiothreitol (DTT),most likely due to shedding of the hydrophilic PEG outer-shell through reductive cleavage of the disulfide *** a hydrophobic anticancer model drug,doxorubicin (DOX) was encapsulated into these reductive unimolecular *** vitro release studies revealed that under the reduction-stimulus,the detachment of PEG outer-shell in DOX-loaded micelles resulted in a rapid drug *** cytometry and confocal laser scanning microscopy (CLSM) measurements indicated that these DOX-loaded micelles were easily internalized by living *** tetrazolium (MTT) assay demonstrated a markedly enhanced drug efficacy of DOX-loaded H40-star-PLA-SS-PEG micelles as compared to free *** of these results show that these bioreducible unimolecular micelles are promising carriers for the triggered intracellular delivery of hydrophobic anticancer drugs.

关键词： hyperbranched polymer unimolecular micelle drug delivery

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Multi-level decollement zones and detachment deformation of Longmenshan thrust belt,sichuan Basin,southwest china

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Science china Earth Sciences 2008年第S2期51卷 32-43页

作者： TANG LiangJie1,2.3,YANG KeMing4,JIN WenZheng1,2.3,L ZhiZhou4 & YU YiXin1,2.3 1 State Key Laboratory of Petroleum Resource and Prospecting,china university of Petroleum,Beijing 102.49,china 2.Key Laboratory for Hydrocarbon Accumulation Mechanism,china university of Petroleum,Ministry of Education,Beijing 102.49,china 3 Basin and Reservoir Research center,china university of Petroleum,Beijing 102.49,china 4 Southwest Division Company,SINOPEC,Chengdu 610081,china 1. State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China 2. Key Laboratory for Hydrocarbon Accumulation Mechanism China University of Petroleum Ministry of Education Beijing 102249 China 3. Basin and Reservoir Research center China University of Petroleum Beijing 102249 China 4. Southwest Division Company SINOPEC Chengdu 610081 China

As is well known that many decollement layers were developed in the Longmenshan thrust belt,Si-chuan Basin,china. Through field investigation,explanation of seismic profiles and analysis of the balanced sections,we can divide the decollement zones into 3 categories: (1) the deep level decolle-ment zones,including the crust-mantle decollement layer,intracrustal decollement layer,and presinian basal decollement layer. The main structural styles of their deformation are the crust-mantle decoup-ling detachment deformation,the basal ductile shear deformation,etc.; (2. the middle level decollement zones,including the Cambrian-Ordovician decollement layer,the Silurian decollement layer,etc.,the main structural styles of their deformation are the isopachous fold,the angular fold,the saddle struc-ture,and the combination styles of them; and (3) the shallow level decollement zones,including the Xujiahe Formation decollement layer of Upper Triassic and the Jurassic decollement layers,the main structural styles of their deformation are the thrust-nappe tectonic,the pop-up,the triangle zone ,the duplex,etc. Multi-level decollement zones not only made the Longmenshan thrust belt develop many different deformation styles from deep place to shallow place,but also made some local areas have the superimposition of the tectonic deformation apparently. This study indicates that the multi-level de-collement zones have a very important effect on the shaping and evolution of the Longmenshan thrust belt.

关键词： decollement layer structural styles multi-level decollement zones Longmenshan thrust belt

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Study on mechanical parameters of fractured rock masses

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Science china(Technological Sciences) 2011年第S1期54卷 140-146页

作者： CHEN WeiZhong 1,2.YANG JianPing 1,TAN XianJun 1 &YU HongDan 1 1 State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,china 2.Research center of Geotechnical and Structural Engineering,Shandong {2.,Jinan 2.0061,china 1. State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China2. Research Center of Geotechnical and Structural Engineering Shandong University Jinan 250061 China

The equivalent strength parameters of fractured rock masses are prerequisite for stability analysis of geotechnical engineering projects constructed in fractured rock masses which are encountered frequently in western *** on generated mesh of fractured rock masses,combined with statistic damage constitutive model of intact rock and damage model of structural plane,progressive failure of fractured rock masses is studied using finite element method(FEM) .Furthermore,Scale effect and anisotropy of compressive strength of fractured rock masses are *** results show that the strength decreases and tend towards stability rapidly from intact rock to fractured rock masses,and the anisotropy of strength of fractured rock masses is not *** last,based on numerical simulation conducted on 10 m scale rock masses under different confining pressures,the equivalent strength parameters of fractured rock masses are gained and the results are compared with Hoek-Brown *** method developed is helpful for determination of strength parameters of fractured rock masses.

关键词： rock mechanics fractured rock masses equivalent strength parameters finite element method scale effect anisotropy

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National 2.00' GPS control network of china

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Progress in Natural Science:Materials International 2007年第8期17卷 983-987页

作者： Yang Yuanxi~(1**) Tang Yingzhe~1 Chen Chuanlu~2.Wang Min~3 Zhang Peng~4 Wang Xiaorui~2.Song Lijie~5 Zhang Zusheng~6 (1.Xi'an Research Institute of Surveying and Mapping,Xi'an 710054,china 2.Geodetic Data Processing center,Xi'an 710054,china 3.center of Earthquake analysis and Prediction,china Seismological Bureau,Beijing 100036,china 4.National Geomatics center of china,Beijing 100044,china 5.Institute of Surveying and Mapping,Zhengzhou university of Information Engineering,Zhengzhou 450052.china 6.First Crustal Deformation Monitoring center,china Seismological Bureau,Tianjin 300180,china) [a]Xi' an Research Institute of Surveying and Mapping Xi' an China [b]Geodetic Data Processing center Xi'an China [c]center of Earthquake analysis and Prediction China Seismological Bureau Beijing China [d]National Geomatics center of Chinna Beijing China [e]Institute of Surveying and Mapping Zhengzhou University of Information Engineering Zhengzhou China [f]First Crustal Deformation Monitoring center China Seimological Bureau Tianjin China

An accurately unified national GPS network with more than 2.00 stations,named"National 2.00' GPS Control Net- work",signed the epoch 2.00.0,has been established by integrating the existing six nationwide GPS networks of china set up by differ- ent departments with different *** paper presents the characteristics of the existing GPS networks,summarizes the strategies in the integrated adjustment of the GPS network,including functional model,stochastic model as well as the adjustment principle modifi- *** modifying the adjustment strategies according to the characteristics of the existing GPS networks and under the support of the IGS stations,the accuracy of the integrated national GPS network is greatly *** datum differences among the sub networks disappear,the systematic error influences are weakened,and the effects of the outliers on the estimated coordinates and their variances are *** is shown that the average standard deviation for the horizontal component is smaller than 1.0 cm,the vertical component is smaller than 2.0 cm,and the three-dimensional (3-D) position of geocenter coordinates is smaller than 3.0 *** exterior checking ac- curacy for the 3-D position is averagely better than 1.0 cm.

关键词： GPS control network adjustment systematic errors robust estimation variance component estimation coordinate system

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Large-scale information entropy analysis of important sites in mature and precursor miRNA sequences

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Science china(Life Sciences) 2009年第8期52卷 771-779页

作者： DU JiangFeng1,2.WU YongJun2.ZHANG YinXia3,WU Lei1,2.WANG XiaoLong3,TAO ShiHeng1,2.1 Bioinformatics center,Northwest Science and Technology university of Agriculture,Yangling 712.00,{2. 2.College of Life Sciences,Northwest Science and Technology university,Yangling 712.00,{2. 3 College of Science,Northwest Science and Technology university,Yangling 712.00,{2. Bioinformatics center Northwest Science and Technology University of Agriculture Yangling 712100 China College of Life Sciences Northwest Science and Technology University Yangling 712100 China College of Science Northwest Science and Technology University Yangling 712100 China

In order to find evidence of consistent sequence conservation or the base correlation degree in miRNA,some important sites in the sequences of reported miRNA and their precursors(pre-miRNA) were investigated via information entropy *** different groups of sites were obtained from special locations(head,tail) in miRNAs of different sources according to taxonomy(animal,plant and virus) and then analyzed by measuring the single base information redundancy(D1(L)) and the adjacent base related information redundancy(D2.L)).The results showed that D2.L) has more information than D1(L),though D1(L) changes roughly consistently with D2.L) in each *** pre-miRNAs are more conservative than those belonging to animals or *** addition,U is dominant in most sites compared with other *** was also found that in the middle of several groups,there were sites where miRNAs were cut down from pre-miRNAs by Enzyme Dicer which were significantly *** phenomenon shows that the conservatism is an aspect of the of miRNA and may be involved in the recognition and cutting by the *** results provided another perspective for understanding more about the primary structure of pre-miRNA.

关键词： miRNA conservative information entropy precursor evolution base correlation degree

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A virtual reference satellite differential method for relative correction of satellite ephemeris errors

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Science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2300-2306页

作者： CAI ChengLin 1,3 , LI XiaoHui 2.3 & WU HaiTao 2.3 1 Gulin university of Electronic Technology, 541004, china 2.National Time Service {2., Chinese Academy of Sciences, Lintong 710600, china 3 Key Laboratory of Precision Navigation and Timing Technology, National Time Service {2., Chinese Academy of Sciences, Lintong 710600, china 1. Gulin university of Electronic Technology Gulin 541004 China3. Key Laboratory of Precision Navigation and Timing Technology National Time Service Center Chinese Academy of Sciences Lintong 710600 China2. National Time Service Center Chinese Academy of Sciences Lintong 710600 China

In order to solve the problems that the novel wide area differential method on the satellite clock and ephemeris relative correction (CERC) in the non-geostationary orbit satellite constellation, a virtual reference satellite (VRS) differential principle using relative correction of satellite ephemeris errors is proposed. It is referred to be as the VRS differential principle, and the elaboration is focused on the construction of pseudo-range errors of VRS. Through qualitative analysis, it can be found that the impact of the satellite’s clock and ephemeris errors on positioning can basically be removed and the users’ positioning errors are near zero. Through simulation analysis of the differential performance, it is verified that the differential method is universal in all kinds of satellite navigation systems with geostationary orbit (GEO) constellation, Medium orbit (MEO) constellation or hybrid orbit constellation, and it has insensitivity to abnormal aspects of a satellite ephemeris and clock. Moreover, the real time positioning accuracy of differential users can be maintained within several decimeters after the pseudo-range measurement noise is effectively weakened or eliminated.

关键词： wide area differential method virtual reference satellite (VRS) satellite ephemeris errors satellite clock errors constellation

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analysis of the carbon source for diamond crystal growth

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Chinese Science Bulletin 2008年第6期53卷 937-942页

作者： LI Li1,2. XU Bin2.3 & LI MuSen1,2.1 School of Materials Science & Engineering, Shandong university, Jinan 2.0061, china 2.Shandong Engineering Research {2. for Super Hard Materials, Zoucheng 2.3500, china 3 School of Materials Science & Engineering, Shandong Jianzhu university, Jinan 2.0101, china School of Materials Science & Engineering Shandong University Jinan China Shandong Engineering Research center for Super Hard Materials Zoucheng China School of Materials Science & Engineering Shandong Jianzhu University Jinan China

The lattice constants of diamond and graphite at high pressure and high temperature (HPHT) were calculated on the basis of linear expansion coefficient and elastic constant. According to the empirical electron theory of solids and molecules (EET), the valence electron structures (VESs) of diamond, graphite crystal and their common planes were calculated. The relationship between diamond and graphite structure was analyzed based on the boundary condition of the improved Thomas-Fermi-Dirac theory by Cheng (TFDC). It was found that the electron densities of common planes in graphite were not continuous with those of planes in diamond at the first order of approximation. The results show that during the course of diamond single crystal growth at HPHT with metal catalyst, the carbon sources forming diamond structure do not come from the graphite structure directly. The diamond growth mechanism was discussed from the viewpoint of valence electron structure.

关键词：钻石晶体生长石墨碳源价电子结构

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Assessment model of dam operation risk based on monitoring data

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Science china(Technological Sciences) 2007年第z1期50卷 144-152页

作者： WU ZhongRu1,2., SU HuaiZhi1,2.& GUO HaiQing1 1 College of Water Conservancy and Hydropower Engineering, Hohai university, Nanjing 2.0098, china 2.National Engineering Research {2. of Water Resources Efficient Utilization and Engineering Safety, Nanjing 2.0098, china 1. College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China 2. National Engineering Research center of Water Resources Efficient Utilization and Engineering Safety Nanjing 210098 China

Although the dams produce remarkable social and economic benefits, the threat made by unsafe dams to the life and property of people who live in the lower river area is un-negligible. Based on the monitoring data which reflect the safety condition of dams, the risk degree concept is proposed and the analysis system and model for evaluating risk degree (rate) are established in this paper by combining the reliability theory and field monitoring data. The analysis method for risk degree is presented based on Bayesian approach. A five-grade risk degree system for dam operation risk and corresponding risk degree is put forward according to the safety condition of dams. The operation risks of four cascade dams on some river are analyzed by the model and approach presented here and the result is adopted by the owner.

关键词： dam monitoring data operation risk degree analysis model

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Review on hidden trouble detection and health diagnosis of hydraulic concrete structures

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Science china(Technological Sciences) 2007年第z1期50卷 34-50页

作者： WU ZhongRu1,2., LI Ji1, GU ChongShi1,2.& SU HuaiZhi1,2.1 College of Water Conservancy and Hydropower Engineering, Hohai university, Nanjing 2.0098, china 2.National Engineering Research {2. of Water Resources Efficient Utilization and Engineering Safety, Nanjing 2.0098, china College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China National Engineering Research center of Water Resources Efficient Utilization and Engineering Safety Nanjing 210098 China

A large number of hydraulic concrete structures have hidden defects such as cracks, erosion, freeze and thaw, thermal fatigue, carbonization. These hidden defects seriously affect the strength, stability and durability of structures. These problems are studied mainly by single monitoring or diagnosis methods at present. The integration of multiple monitoring and diagnosis methods is not applied widely. Besides, the analysis theory on these problems is not developed very well. The systemic study on the aging mechanism of hydraulic concrete structures, time- variation model and health diagnosis is still not enough. The support for engineering practice is limited. Aimed at these major scientific and technological problems and combined with specific projects, study on detection of hidden defects and health diagnosis of hydraulic concrete structure has been carried out. This study includes the following content: field non-destructive examination of hidden defects of hydraulic concrete structures, seepage detection, the construction of in-situ sensing system, the combination of field detection and in-situ monitoring, the mechanism of crack, freeze and thaw, erosion and carbonization of hydraulic concrete structure, mechanism of combination aging; time-variation model of hydraulic concrete structure, theories and methods for health diagnosis of hydraulic concrete structures.

关键词： hydraulic concrete structure hidden trouble detection health diagnosis

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