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Expression of a Modified Cry1Ie Gene in E. coli and in Transgenic Tobacco Confers Resistance to Corn Borer

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 309-313页

作者： Yun-Jun LIU, Fu-Ping SONG1, Kang-Lai HE1, Yuan YUAN, Xiao-Xia ZHANG, Peng GAO, Jian-Hua WANG, and Guo-Ying WANG * state key laboratory for Agrobiotechnology, national Center for Maize Improvement, china Agricultural University, Beijing 100094, china 1state key laboratory for biology of Plant Diseases and Insect Pests, institute of Plant Protection, CAAS, Beijing 100094, china state key laboratory for Agrobiotechnology National Center for Maize Improvement China Agricultural UniversityBeijing 100094 China state key laboratory for biology of Plant Diseases and Insect Pests Institute of Plant ProtectionCAAS Beijing 100094 China

The wild-type Cry1Ie gene from Bacillus thuringiensis was modified for its efficient expression in transgenic plants. Modified Cry1Ie gene (designated as Cry1Iem) was cloned into prokaryotic expression vector pET28b and its expression in E. coli was confirmed by SDS-PAGE analysis. Bioassays using crude expression products in E. coli revealed that Cry1Iem protein had a similar toxicity to corn borer as wild-type Cry1Ie. Cry1Iem gene was then inserted downstream of the maize ubiquitin-1 promoter in plant expression vector p3301. Transgenic tobacco plants carrying Cry1Iem showed insecticidal activity against corn borer.

关键词： Bacillus thuringiensis Cry1Iem transgenic tobacco insect-resistance

A three-dimensional k-ε-k_p model in curvilinear coordinates for sediment movement and bed evolution

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Science china(Technological Sciences) 2009年第4期52卷 1090-1100页

作者： SHEN YongMing1 & LIU Cheng2 1 state key laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116023, china 2 Pearl River Hydraulic research institute, Guangzhou 510611, china state key laboratory of Coastal and Offshore Engineering Dalian University of Technology Pearl River Hydraulic research institute

To aim at the substitution of the magnitude and direction of water flow movement near bed for those of bed load transport in solid-liquid two-phase one-fluid model, and to simulate the effect of secondary flow on transverse bed load transport in channel bends and the effect of bed slope on bed load trans- port in a better way, a three-dimensional k-ε-kp solid-liquid two-phase two-fluid model in curvilinear coordinates is solved numerically with a finite-volume method on an adaptive grid for studying wa- ter-sediment movements and bed evolution in a 120° channel bend. Numerical results show that the trajectories of solid-phase deviate from those of liquid-phase in the channel bend, and the deviation increases with the increase of the particle diameters. The calculated bed deformation by the k-ε-kp model is in better agreement with measured bed deformation than those by one-fluid model. It is proved that the k-ε-kp model can simulate the effect of secondary flow on lateral bed load transport with the higher accuracy than the one-fluid model.

关键词： curvilinear coordinates three-dimensional k-ε-kp model two-fluid model solid-liquid flows channel bend bed load bed evolution tra- jectory

Hydraulic characteristics of converse curvature section and aerator in high-head and large discharge spillway tunnel

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Science china(Technological Sciences) 2011年第S1期54卷 33-39页

作者： LIU ZhiPing 1,2,ZHANG Dong 2,ZHANG HongWei 2 &WU YiHong 1,2 1 state key laboratory of Simulation and Regulation of Water Cycle in River Basin,Beijing 100038,china 2 china institute of Water Resources and Hydropower research,Beijing 100038,china state key laboratory of Simulation and Regulation of Water Cycle in River Basin china institute of Water Resources and Hydropower research

The hydraulic characteristics and cavitation erosion near the converse curvature section in the high-head and large discharge spillway tunnel have been important issues of concern to the hydropower *** this paper,the evolutions of hydraulic elements such as pressure,flow velocity,wall shear stress,*** the converse curvature section are analyzed and the impacts of bottom aerator on hydraulic characteristics are discussed,with the commercial software FLUENT6.3 as a platform and combining the k-model and VOF *** flow pattern in the converse curvature section of spillway tunnel is given by the three-dimensional numerical *** indicates that the pressure changes rapidly with great pressure gradient from the beginning to the end of the *** also shows that the shear stress on side wall just downstream the end of the converse curvature curve is still increasing;the aeration cavity formed downstream the bottom aerator may cause the side wall pressure decreased to worsen the cavitation characteristics near the side *** means of the physical model experiment,the three-dimensional aerator composed of side wall baffling aerator and bottom aerator is studied,the baffling aerator suitable for the water flow conditions with water depth of 6.0 to 8.0 m and flow velocity of 35 to 50 m/s is proposed.

关键词： spillway tunnel baffling aerator converse curvature section hydraulic characteristics

QTL Mapping and Epistasis Analysis for Yield Traits in an RIL Population of rice(Oryza sativa L.)

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Agricultural Sciences in china 2003年第11期2卷 1179-1186页

作者： CAO Li-yong, ZHAN Xiao-deng, ZHUANG Jie-yun, ZHENG Kang-le and CHENG Shi-hua(national Center for rice Improvement, china national rice research institute, hangzhou 310006 , P. R. china) national Center for rice Improvement China National Rice Research Institute Hangzhou 310006 P.R. China

A genetic linkage map consisting of 168 DNA markers was constructed based on a recombinant inbred line(RID population derived from a cross between a high yielding indica variety, Zhong156, and a low yielding indica variety, Gumeil. The markers on the linkage map were distributed on all 12 chromosomes and covered 1 447. 9 cM of the genome. The parents and 304 RILs were grown in china national rice research institute(CNRRI), hangzhou, china, in 2001, over two seasons in a randomized block design. The statistic software of QTL Mapper 1.01 was applied to detect quantitative trait loci(QTLs)and additive by environment(AE)interactions for yield traits, including panicle length, number of panicles per plant, number of spikelets per panicle, number of filled grains per panicle, fertility and kilo-grain weight. A total of 30 QTLs with significant additive effects located on all chromosomes, except chromosomes 5 and 9, and two QTLs with significant AE interactions, were detected. Thirty-one interactions of QTLs showing significant additive by additive epistatic effects for yield traits were also detected. Genetic contributions were generally lower for QTLs showing epistatic effects compared with QTLs showing additive effects. No significant interactions between epistasis and environment were detected.

关键词： Yield traits QTLs Additive effect Epistasis Oryza sativa L.

Rashba electron transport in one-dimensional quantum waveguides

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Science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 16-23页

作者： LIU DuanYang 1 , XIA JianBai 1,2 & CHANG YiaChung 2 1 state key laboratory for Superlattices and Microstructures, institute of Semiconductors, Beijing 100083, china 2 research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan 11529, china institute of Semiconductors State Key Laboratory for Superlattices and Microstructures Beijing China (GRID:grid.454865.e) (ISNI:***) institute of Semiconductors State Key Laboratory for Superlattices and Microstructures Beijing China (GRID:grid.454865.e) (ISNI:***) Academia Sinica Research Center for Applied Sciences Taipei Taiwan China (GRID:grid.9227.e) (ISNI:***) Academia Sinica Research Center for Applied Sciences Taipei Taiwan China (GRID:grid.9227.e) (ISNI:***)

The properties of Rashba wave function in the planar one-dimensional waveguide are studied, and the following results are obtained. Due to the Rashba effect, the plane waves of electron with the energy E divide into two kinds of waves with the wave vectors k 1 =k 0 +k δ and k 2 =k 0 -k δ , where k δ is proportional to the Rashba coefficient, and their spin orientations are +π/2 (spin up) and -π/2 (spin down) with respect to the circuit, respectively. If there is gate or ferromagnetic contact in the circuit, the Rashba wave function becomes standing wave form exp(±ik δ l)sin[k 0 (l-L)], where L is the position coordinate of the gate or contact. Unlike the electron without considering the spin, the phase of the Rashba plane or standing wave function depends on the direction angle θ of the circuit. The travel velocity of the Rashba waves with the wave vector k 1 or k 2 are the same hk0/m * . The boundary conditions of the Rashba wave functions at the intersection of circuits are given from the continuity of wave functions and the conservation of current density. Using the boundary conditions of Rashba wave functions we study the transmission and reflection probabilities of Rashba electron moving in several structures, and find the interference effects of the two Rashba waves with different wave vectors caused by ferromagnetic contact or the gate. Lastly we derive the general theory of multiple branches structure. The theory can be used to design various spin polarized devices.

关键词： Rashba wave function one-dimensional waveguide boundary condition

Theoretical observation of hexaatomic molecules containing pentacoordinate planar carbon

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Science china Chemistry 2008年第11期51卷 1030-1035页

作者： LUO Qiong state key laboratory of Explosion Science and Technology, Beijing institute of Technology, Beijing 100081, china state key laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing China

The smallest molecules up to date containing a D5h pentacoordinate planar carbon (PPC) atom, CBe5 and CBe54-, are presented by means of ab initio calculations. To gain a better understanding about which electronic factors contribute to their stabilization, natural bond orbital (NBO) analysis and the nucleus independent chemical shifts (NICS) were calculated. The data reported here suggest that D5h CBe5 is σ aromaticity in nature, while in D5h CBe54- π aromaticity is dominating. The classical octet rule is well satisfied in both molecules, and is one of the fundamental reasons to understand the stability of the pentagon structures. The Be5 ring serves as σ donor in D5h CBe5, and π-acceptor in D5h CBe54-. The D5h CBe54- possessing 18 valence electrons with a closed-shell electron configuration is the most plau-sible candidate for experimental detection.

关键词： pentacoordinate planar carbon Be5 ring ab initio

Phylogenetic relationship and phenotypic comparison of Psychrobacter species isolated from polar oceans

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Progress in Natural Science:Materials International 2007年第1期17卷 44-48页

作者： ZENG Yinxin, LI Huirong, YU Yong and CHEN Bo (key laboratory for Polar Science of state Oceanic Administration, Polar research institute of china, Shanghai 200136, china) key laboratory for Polar Science of state Oceanic Administration Polar Research Institute of China Shanghai 200136 China

To investigate the phylogenetic relationship and biogeography of bacterioplankton in polar oceans, four Psychrobacter strains, BSw10170, BSw20352, BSw20370, and BSw20461, isolated from seawater of the Beijing Sea, the Chukchi Sea, and the Prydz Bay, were characterized by 16S rDNA sequencing and physiological and biochemical testing. Results demonstrated that close relationships existed between the Arctic and Antarctic strains with sequence similarities higher than 97 %. These four Psychrobacter strains not only showed almost identical phenotypic characteristics among them, but also shared a lot of similarities with those related Psychrobacter species, indicating that psychrotolerance and halotolerance of Psychrobacter strains may be among the reasons for their bipolar, even global distribution in marine environments at the genus level.

关键词： Psychrobacter phylogenetic phenotypic Arctic Antarctic.

Quantitative Trait Loci for Yield Traits Located Between Hd3a and Hd1 on Short Arm of Chromosome 6 in rice

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rice science 2011年第4期18卷 257-264页

作者： Ye-yang FAN Chen CHEN Ji-rong WU Shi-hua CHENG Jie-yun ZHUANG Chinese national Center for rice Improvement / state key laboratory of rice biology China National Rice Research Institute Hangzhou 310006 China

QTLs for heading date located in the regions of Hd3a and Hd1 were detected using an F2:3 population developed from a residual heterozygous line(RHL) identified from the recombinant inbred lines of the indica rice cross Zhenshan 97B /Milyang *** in coupling phase between the QTLs for heading date and yield traits detected in a previous study was *** more F2:3 populations were each developed from an RHL that was homozygous at Hd3a and Hd1 but heterozygous in a portion of the intervals flanked by Hd3a and *** for grain yield per plant,number of panicles per plant,number of grains per panicle and 1000-grain weight were detected in the heterozygous *** sets of near-isogenic lines(NILs) with overlapping heterogenous segments covering the interval RM6119-RM6779 were developed and used to validate and delimitate the QTLs.A QTL conferring a consistent effect for the number of grains per panicle was located within the interval RM19615-RM19652 that corresponded to a 514.4-kb region on chromosome *** same region might have pleiotropic effects on the other three yield-related traits analyzed,but the effects varied greatly among different populations and across different *** study suggests that it is possible to develop a population with little variation on heading date and to identify QTLs for yield traits that might not be associated with heading date by using the information of physical positions of DNA markers and cloned genes.

关键词： rice yield trait heading date quantitative trait locus residual heterozygous line

Dissection of QTLs for Hull Silicon Content on the Short Arm of rice Chromosome 6

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rice science 2010年第2期17卷 99-104页

作者： Wu Ji-rong FAN Fang-jun DU Jing-hong FAN Ye-yang ZHUANG Jie-yun Chinese national Center for rice Improvement/state key laboratory of rice biology China National Rice Research InstituteHangzhou 310006 China

The QTL qHUS6 for hull silicon content in rice was previously located on the short arm of rice chromosome 6. By using an F2：3 population segregating in the RM587-RM19784 region harboring qHUS6 in an isogenic background, two QTLs for hull silicon content were detected, of which qHUS6-1 was located in the distal region and qHUS6.2 in the region proximal to the centromere. Three rice plants carrying small heterozygous segments in the target region were selected, of which two covered the qHUS6-1 region and the other covered the qHUS6-2 region. Three F2：3 populations were derived from the selfed seeds of the three plants, respectively. QTL mapping was performed using the two populations segregating in the qHUS6-1 region, and qHUS6-1 was delimited to a 147.0-kb region flanked by the markers RM510 and RM19417. Five groups of F3 lines with different genotypic compositions in the qHUS6-2 region were selected from the other F2-3 population. Two QTLs were separated with two-way ANOVA, of which qHUS6-2a was located in the interval defined by RM19706-RM19795 and qHUS6-2b in the interval RM314-RM19665.

关键词： rice (Oryza safiva) quantitative trait locus residual heterozygous line hull silicon content gene mapping