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TALEN-Mediated Homologous Recombination Produces Site-Directed DNA Base Change and Herbicide-Resistant Rice

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Journal of Genetics and Genomics 2016年第5期43卷 297-305页

作者： Ting Li bo Liu Chih Ying chen Bing Yang Department of Genetics Development and Cell BiologyIowa State University Division of Biology and Biological Engineering California Institute of Technology

Over the last decades,much endeavor has been made to advance genome editing technology due to its promising role in both basic and synthetic *** breakthrough has been made in recent years with the advent of sequence-specific endonucleases,especially zinc finger nucleases（ZFNs）,transcription activator-like effector nucleases（TALENs） and clustered regularly interspaced short palindromic repeats（CRISPRs） guided nucleases（e.g.,Cas9）.In higher eukaryotic organisms,site-directed mutagenesis usually can be achieved through non-homologous end-joining（NHEJ） repair to the DNA double-strand breaks（DSBs） caused by the exogenously applied ***,site-specific gene replacement or genuine genome editing through homologous recombination（HR） repair to DSBs remains a *** a proof of concept gene replacement through TALEN-based HR in rice（Oryza sativa）,we successfully produced double point mutations in rice acetolactate synthase gene（OsALS） and generated herbicide resistant rice lines by using TALENs and donor DNA carrying the desired *** ballistic delivery into rice calli of TALEN construct and donor DNA,nine HR events with different genotypes of OsALS were obtained in T_0 generation at the efficiency of 1.4%—6.3%from three *** HRmediated gene edits were heritable to the progeny of T_1 *** edited T_1 plants were as morphologically normal as the control plants while displayed strong herbicide *** results demonstrate the feasibility of TALEN-mediated genome editing in rice and provide useful information for further genome editing by other nuclease-based genome editing platforms.

关键词： TALEN Genome editing Homologous recombination Gene replacement Site-directed mutagenesis Acetolactate synthase Herbicide resistance Rice

Effect of the current density on electrodepositing alpha-lead dioxide coating on aluminum substrate

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Acta Metallurgica Sinica(English Letters) 2009年第5期22卷 373-382页

作者： Burning chen Zhongcheng GUO hui HUANG Xianwan YANG Yuandong CAO Faculty of Materials and Metallurgical Engineering Kunming University of Science and TechnologyKunming 650093 China

The α-Pbo2 electrodes are prepared by anodic electrodeposition on Al/conductive coating electrode from alkaline plumbite solutions in order to investigate the effect of the different current densities on the properties of α-Pbo2 electrodes. The physic- ochemical properties of the α-Pbo2 electrodes are analyzed by using SEM, EDS, XRD, Tafel plot, linear sweep voltammetry （LSV） and A.C. impedance. A compact and uniform layer of lead dioxide ：）vas obtained at the current density of 3 ***-2. A further increase in current density results in smaller particles with high porosity. EDS and XRD analyses have shown that the Pbo2 deposited in alkaline conditions is highly non stoichiometric, and the Pbo impurities are formed on the surface layer besides the α-Pbo2. The corrosion resistance of α-Pbo2 at the low current density is superior to that of the high current density. It can be attributed to a porous layer of deposited films at high current densities in aqueous Zn2＋ 50 g·L^-1, H2SO4 150 When used as anodes for oxygen evolution g·L^-1, the Al/conductive coating/α-Pbo2 exhibits lower potential compared to Pb electrode. Al/conductive coating/α-Pbo2 electrode with the best electrocatalytic activity was obtained at current density of 1 mA·cm^-2. The lowest roughnest factor was obtained at 1 mA·cm^-2.

关键词： Alpha lead dioxide Electrodeposition Current density Anodes Oxygen evolution

New Methods of Determining the Mixed Mode Stress Intensity Factors for V-Shaped Notch

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上海交通大学学报 2004年第z2期38卷 188-193页

作者： Lin Zhong-qin Yu Haiyan chen Guanlong Li Shu-hui School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 P.R.China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 P.R.China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 P.R.China School of Mechanical Engineering Shanghai Jiaotong University Shanghai200030 P.R.China

In this paper, on the basis of the stress field given by ***, three new photoelastic methods are developed for determining the stress intensity factors K1 and K2 of V-shaped notch. Some photoelastic experiments are performed on a skew -symmetric 45° notch. Measurements of the coordinates components of r,θand fringe order N are made for progressively smaller fringes and used in the proposed methods to solve K1 and *** of apparent K vs. r/l are made and extrapolated to the notch tip to yield the true values of K1 and *** results obtained by the three methods are very close to each other. When the notch problem is simplified as a crack problem, the corresponding equation is identical to the one proposed by D.G. Smith, which shows that the proposed methods are applicable for both notch and crack problems.

关键词： photoelastic stress intensity factors isochromatic fringe V-shaped notch

Reactions between the SO^(·-)_4 radical and some common anions in atmospheric aqueous droplets

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Journal of Environmental Sciences 2005年第5期17卷 786-788页

作者： OUYANG Bin FANG Hao-jie ZHU cheng-zhu DONG Wen-bo HOU hui-qi Laser Flash Photolysis Laboratory Institute of Environmental Science Fudan University Shanghai 200433 China

The rate constants of reactions between the SO4^- radical and some common anions in atmospheric aqueous droplets e.g. Cl^-,NO^-, HSO3^- and HCO3^- were determined using the laser flash photolysis *** spectra of SO4^- and the product radicals were also *** chloride ion was evaluated among all the anions to be the most efficient scavenger of SO4^-.The results may supply useful information for a better understanding of the vigorous radical-initiated reactions in atmospheric aqueous droplets such as clouds, rains or fogs.

关键词： sulfate radical common anions atmospheric aqueous-phase chemistry radical chemistry

Analysis of precipitation behavior of MnS in sulfur-bearing steel system with finite-difference segregation model

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Journal of Iron and Steel Research International 2018年第8期25卷 803-812页

作者： De-lin Hu hui Liu Jian-bo Xie Juan cheng Jian Li Jian-xun Fu State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferrometallurgy and School of Materials Science and Engineering Shanghai University Shanghai 200444 China

To further reveal the influence of micro-segregation on the precipitation behavior of MnS in sulfur-bearing steel system, a coupled model of micro-segregation and MnS precipitation was established by the finite-difference method based on various calculation domains and the solid diffusion degrees, and a new controlled diffusion equation with more stable convergence was also used. 49MnVS3 and 1215 steels were used to analyze the influence of calculation domain, segregation model and S content on the precipitation behavior of MnS. The calculation results were verified by a high- temperature confocal laser scanning microscope （HT-CLSM）. The results show that the domain has little effect on the precipitation temperature, precipitation solid fraction and precipitation amount of MnS, but affects the precipitation location and segregation of the solutes. For low- and medium-sulfur steels, the temperatures calculated by the diffusion control growth （DCG） model and the Lever model were nearly identical, whereas the temperature calculated by the Scheil model was lower. However, for high-sulfur steels, the precipitation temperatures calculated by three segregation models were nearly same. The precipitation solid fraction is more reasonable to describe the precipitation behavior of MnS. The precipitation behavior of MnS, observed by the HT-CLSM, matches well with that in the DCG model.

关键词： MnS precipitation Micro-segregation Mathematical model Solidification In situ observation

Effect of Nb on the corrosion behavior of continuous bulk metallic glass-coated steel wire composites

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International Journal of Minerals,Metallurgy and Materials 2013年第6期20卷 589-592页

作者： Xiao-hua chen Bao-yu Zhang Xi-dong hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

（***10Be22.5）100-~Nb~ （at%, x=0 and 8） bulk metallic glasses （BMGs） were coated on the surface of Q195 steel wires by a continuous coating process. The potentiodynamic polarization tests of these BMGs were conducted in 3.5wt% NaC1 aqueous solution. It is found that the addition of 8at% Nb into ***10Be22.5 alloy results in the improvement of corrosion resistance with the pitting potential of -52 mV, the open circuit potential of-446 mV, and the corrosion current density of 9.86x 10-6 mA/cm2. This may be attributed to that Nb is beneficial to passivate and stabilize Zr and Ti.

关键词： composite materials metallic glass coatings corrosion niobium

Study on effect of Traditional Chinese Medicine Jianpi Chushi decoction and ointment on chronic eczema

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Asian Pacific Journal of Tropical Medicine 2016年第9期9卷 897-900页

作者： hui-Lei Wan hui-Zhi chen Xiu-Qin Shi Department of Medical Affairs People's Hospital of Zhengzhou Department of Clinical Laboratory the First Affiliated Hospital of Zhengzhou University Department of Pharmacy the First Affiliated Hospital of Zhengzhou University

Objective:To study the effects of Traditional Chinese Medicine Jianpi Chushi decoction and ointment on chronic ***:DNCB acetone solution was used to sensitize the skin of back and ears of 36 rats in order to establish chronic eczema model.A total of 36 rats were divided into four groups of 9 randomly including oral medicine group,external inunctum group,combination therapy group,and model control group ***,the blank group of 4 healthy rats were *** oral medicine group was given Traditional Chinese Medicine Jianpi Chushi decoction [(Poria cocos,Chinese yam,Cortex dictamni,Zaocys dhumnade,Rhizoma atractylodis,Pericarpium citri reticulatae,Scutellaria baicalensis,Radix Sophorae Flavescentis,Raw Radix Paeoniae Alba,Licorice roots(Northwest Origin)] by gastric infusion(1.6 g/m L·5 m L/d); the external inunctum group was given Qingpeng ointment on the skin,the combination therapy group was given Jianpi Chushi decoction by gastric infusion and Qingpeng ointment combination *** model control group was given normal saline(NS) of the same volume by gastric infusion and vaseline on *** administration 15 d and stopped for 3 *** thickness difference and weight difference of left and right ear of every group were measured and the degree of ear swelling were *** CD4^+ and CD8^+ content and the IL-2,IL-4 level of serum were detected,and the inflammatory cells counts of back skin were ***:After treatment,the degree of ear swelling of oral medicine group,external inunctum group and combination therapy group significant decreased compared with model control group(P<0.05).The CD4^+,CD8^+ cell content and IL-2 level of oral medicine group,external inunctum group,combination therapy group and model control group significant decreased compared with blank group,and IL-2 level and the inflammatory cells count *** 15 d of treatment,the CD4^+,CD8^+ cell content and IL-2 level of serum of oral medicine gro

关键词： Chronic eczema Rat Jianpi Chushi decoction Qingpeng ointment Combination therapy

Simulation of top-down crack propagation in asphalt pavements

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第3期11卷 223-230页

作者： hui LUO Hong-ping ZHU Yu MIAO Chuan-yao chen School of Civil Engineering and Mechanics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Control Structure Huazhong University of Science and TechnologyWuhan 430074China

Top-down crack in asphalt pavements has been reported as a widespread mode of failure.A solid understanding of the mechanisms of crack growth is essential to predict pavement performance in the context of thickness design,as well as in the design and optimization of *** the coupled element free Galerkin (EFG) and finite element (FE) method,top-down crack propagation in asphalt pavements is numerically simulated on the basis of fracture mechanics.A parametric study is conducted to isolate the effects of overlay thickness and stiffness,base thickness and stiffness on top-down crack propagation in asphalt *** results show that longitudinal wheel loads are disadvantageous to top-down crack because it increases the compound stress intensity factor (SIF) at the tip of top-down crack and shortens the crack path,and thus the fatigue life *** SIF experiences a process "sharply ascending—slowly descending—slowly ascending—sharply ascending again" with the crack *** thicker the overlay or the base,the lower the SIF; the greater the overlay stiffness,the higher the *** crack path is hardly affected by stiffness of the overlay and base.

关键词： Road engineering Top-down crack Coupled element free Galerkin (EFG) and finite element (FE) method Stress intensity factor (SIF) Crack propagating path

Multi-mode controller IC for soft-switched flyback converter with high efficiency over the entire load range

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1411-1419页

作者： Hai chen Meng-lian ZHAO Xiao-bo WU Xiao-lang YAN Institute of VLSI Design Zhejiang University Hangzhou 310027 China

This paper presents a multi-mode control scheme for a soft-switched flyback converter to achieve high efficiency and excellent load regulation over the entire load range. At heavy load, critical conduction mode with valley switching (CCMVS) is employed to realize soft switching so as to reduce turn-on loss of power switch as well as conducted electromagnetic interference (EMI). At light load, the converter operates in discontinuous conduction mode (DCM) with valley switching and adaptive off-time control (AOT) to limit the switching frequency range and maintain load regulation. At extremely light load or in standby mode, burst mode operation is adopted to provide low power consumption through reducing both switching frequency and static power dissipation of the controller. The multi-mode control is implemented by an oscillator whose pulse duration is adjusted by output feedback. An accurate valley switching control circuit guarantees the minimum turn-on voltage drop of power switch. The pro-totype of the controller IC was fabricated in a 1.5-μm BiCMOS process and applied to a 310 V/20 V, 90 W flyback DC/DC converter circuitry. Experimental results showed that all expected functions were realized successfully. The flyback converter achieved a high efficiency of over 80% from full load down to 2.5 W, with the maximum reaching 88.8%, while the total power consumption in standby mode was about 300 mW.

关键词： Integrated circuit Multi-mode controller Soft-switched flyback converter Valley detection