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Genome engineering technologies for targeted genetic modification in plants

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Journal of Forestry Research 2018年第4期29卷 875-887页

作者： Wei tang Anna y. tang College of Arts and Science East Carolina University Greenville NC 27858 USA University of North Carolina at Chapel Hill 101 Stadium Drive Chapel Hill NC 27514 USA

Well-established targeted technologies to engi- neer genomes such as zinc-finger nuclease-based editing （ZFN）, transcription activator-like effector nuclease-based editing （tALEN）, and clustered regularly interspaced short palindromic repeats and associated protein system-based editing （CRISPR/Cas） are proving to advance basic and applied research in numerous plant species. Compared with systems using ZFNs and tALENs, the most recently developed CRISPR/Cas system is more efficient due to its use of an RNA-guided nuclease to generate double-strand DNA breaks. to accelerate the applications of these technologies, we provide here a detailed overview of these systems, highlight the strengths and weaknesses of each, summarize research advances made with these technologies in model and crop plants, and discuss their applications in plant functional genomics. Such targeted approaches for genetically modifying plants will benefit agricultural production in the future.

关键词： Double-stranded DNA break Genomeediting CRISPR system transcription activator-likeeffector nucleases Zinc-finger nucleases

Synthesis of perovskite BataO_(2)N with low defect by Zn doping for boosted photocatalytic water reduction

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Journal of Energy Chemistry 2021年第12期30卷 358-363,I0009页

作者： yunfeng Bao Hai Zou Nengcong yang Gao Li Fuxiang Zhang State Key Laboratory of Catalysis iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian National Laboratory for Clean EnergyDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Perovskite BataO_(2) N(BtON) is one of the most promising photocatalysts for solar water splitting due to its wide visible-light absorption and suitable conduction/valence bands,but it still confronts the challenge of high defect density causing decreased charge separation as well as photocatalytic *** this work,we develop a simple zinc doping strategy to greatly suppress its defect density and promote its water reduction *** is found that the defect formation on the nitrided Ba(Zn_(1/3-x)ta_(2/3))O_(3-y)N_z(denoted as BZtON hereafter) will be greatly inhibited when the Zn-doped Ba(Zn_(1/3)ta_(2/3))O_(3)(BZtO) oxide is used as the nitridation *** structural characterizations and discussion demonstrate that the effective inhibition of ta^(5+)into ta^(4+)defects in BZtON mainly results from the easy reduction of zinc ions into metal and further the evaporation of zinc metal under the thermal ammonia ***,this simply doping methodology can be easily extended into the synthesis of SrtaO_(2) N(StON) with extremely low defect density,demonstrating its *** from the successful control to the defect density,the as-obtained BZtON photocatalyst exhibits remarkably promoted charge separation as well as water reduction activity to produce hydrogen with respect to the pristine *** work may provide an alternative avenue to prepare oxynitride semiconductors with reduced defect density for promoted solar energy conversion.

关键词： Oxynitride Photocatalyst Water splitting Defect density Zinc doping

Cretaceous volcanic-intrusive magmatism in western Guangdong and its geological significance

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Science China Earth Sciences 2006年第7期49卷 696-713页

作者： S. y. O’Reilly GEMOC ARC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Systematic zircon LA-ICPMS U-Pb dating reveals that Cretaceous volcanic-intrusive activities developed in western Guangdong. Representative volcanic rocks, i.e. Maanshan and Zhougongding rhyodacites, have zircon U-Pb isotopic ages of 100±1 Ma, and the intrusive ones in-cluding the Deqing monzonitic granite body and the Xinghua granodiorite body in the Shidong com-plex, as well as the tiaocun granodiorite body in the Guangping complex yield ages of 99±2 Ma, ca. 100 Ma, and 104±3 Ma respectively. the biotite-granites of the Shidong complex main body (461±35 Ma) and that of the Guangping complex (444±6 Ma) are Caledonian. In spite of the big time interval between Cretaceous volcanic-intrusive magmatisms and Caledonian intrusive ones, both of them are characterized by enrichment in Rb, th, Ce, Zr, Hf, Sm, depletion in Ba, Nb, ta, P, ti, Eu, and weakly REE tetrad effect. Eu negative anomalies are: Cretaceous volcanic rocks (Eu/Eu*=0.74), Cretaceous intrusive rocks (Eu/Eu*=0.35―0.58), Caledonian biotite granites (Eu/Eu*=0.31―0.34). Studies of Sr-Nd isotope data show that all these igneous rocks have high initial 87Sr/86Sr ratios (0.7105―0.7518), and low εNd(t) values (?7.23―?11.39) with their Nd two-stage model ages ranging from 1.6―2.0 Ga, which suggest that they all derived from the Proterozoic crustal basement of southeast China. the occurrence of Cretaceous volcanic-intrusive magmatisms in western Guangdong is related with the important lithospheric extension event in southeast China (including Nanling region) at ca. 100 Ma. the “volcanic line” defined by the large scale Mesozoic intermediate-acidic volcanic magmatisms in southeast China may further extend to the southwest margin of Nanling region.

关键词： Cretaceous, volcanic-intrusive rocks, zircon U-Pb dating, Sr-Nd isotope, western Guangdong.

MULtIAXIAL CREEP-FAtIGUE LIFE EVALUAtION UNDER PROPORtIONAL LOADING

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 355-360页

作者： y.Noguchi M.Miyahara Corporate Research & Development Laboratories Sumitomo Metal Industries Ltd. Amagasaki Hyogo 660-0891 JapanCorporate Research & Development Laboratories Sumitomo Metal Industries Ltd. Amagasaki Hyogo 660-0891 Japan

A new method was proposed for the multiaxial creep-fatigue life evaluation under proportional loadings. Because this method was derived from the strain range partitioning method with a multiaxiality factor, it was possible to consider the influence of both creep-fatigue interaction and multiaxial stress state on fatigue life. In order to predict the combined axial-torsional fatigue life the damage under combined loading was defined as linear summation of the damages under axial loading and torsional loading. Axial-torsional creep-fatigue tests were carried out using tubular specimens of 316LC austenitic stainless steel and the ferritic rotor steel. this rotor steel was developed for the permanent magnet type eddy current retarder in heavy trucks. Experimentally obtained lives of both steels were well corresponded with the lives predicted by the proposed method. It was found that the proposed method was effective in multiaxial fatigue life evaluation under proportional creep-fatigue loadings.

关键词： multiaxial fatigue creep-fatigue proportional loading life evaluation

Studies on monodispersed colloidal particles of doped yttrium compounds

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Chinese Journal of Chemistry 1995年第3期13卷 199-206页

作者： DENG, HM XU, y GU, yD FUDAN UNIV ANAL & MEASUREMENT RES CTRSHANGHAI 200433PEOPLES R CHINA FUDAN UNIV DEPT CHEMSHANGHAI 200433PEOPLES R CHINA

Monodispersed particles of doped yttrium basic carbonates were prepared at aging at elevated temperature corresponding salts solutions in the presence of urea. Coprecipitation in mixed solutions of yttrium, lanthanum and neodymium salts under similar experimental conditions yielded composite particles of basic carbonates. the content of the three metals in the solids followed closely the initial composition of the reacting solutions. On calcination all prepared solids converted to their corresponding oxides while retaining their particle morphology. the so‐prepared powders were characterized by various techniques.

关键词： yttRIUM COMPOUNDS MONODISPERSED PARtICLES UREA DECOMPOSItION

Self-/conspecific discrimination and superparasitism strategy in the ovicidal parasitoid Echthrodelphax fairchildii （Hymenoptera： Dryinidae）

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Insect Science 2014年第6期21卷 741-749页

作者： Emi Ito yoshihiro y. yamada Insect Ecology Laboratory Graduate School of Bioresources Mie University Tsu Mie Japan

Superparasitism in solitary parasitoids results in fatal competition between the immature parasitoids, and consequently only one individual can emerge. In the semisoli- tary ovicidal parasitoid Echthrodelphaxfairchildii （Hymenoptera： Dryinidae）, 2 adults can emerge under superparasitism with a short interval （〈24 h） between the first and second ovipositions. We determined the female parasitoid＇s behavioral responses under self- and conspecific superparasitism bouts with first-to-second oviposition intervals of 〈2 h. the self- and conspecific superparasitizing frequencies increased up to an oviposition interval of 0.75 h, with the former remaining lower than the latter, particularly for oviposition intervals of _〈0.25 h, suggesting the existence of self-/conspecific discrimination. the superparasitizing frequency plateaued for oviposition intervals of _〉0.75 h, with no dif- ference between self- and conspecific superparasitism. the ovicidal-probing frequency did not differ under self- and conspecific superparasitism, and was usually 〈20%. the females exhibited no preference for the oviposition side （i.e., ovipositing on the side with or without the first progeny） and almost always laid female eggs for any oviposition in- terval under self- and conspecific superparasitism. the sex ratio was not affected by the type of superparasitism, oviposition sides, or the occurrence of ovicidal probing. these observed results about the oviposition side, ovicidal probing, and sex ratios differed from the predictions obtained assuming that the females behave optimally. Possible reasons for the discrepancies are discussed： likely candidates include the high cost of selecting oviposition sides and ovicidal probing, and, for the sex ratio, the low frequency of encountering suitable hosts before superparasitism bouts.

关键词： infanticide ovicide plant hopper self-recognition sex ratio

A Deep Learning-Based Phenotypic Analysis of Rice Root Distribution from Field Images

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Plant Phenomics 2020年第1期2卷 324-333页

作者： S.teramoto y.Uga Institute of Crop Science National Agriculture and Food Research Organization2-1-2 KannondaiTsukubaIbaraki 305-8518Japan

Root distribution in the soil determines plants’nutrient and water uptake ***,root distribution is one of the most important factors in crop *** trench profile method is used to observe the root distribution underground by making a rectangular hole close to the crop,providing informative images of the root distribution compared to other root phenotyping ***,much effort is required to segment the root area for *** this study,we present a promising approach employing a convolutional neural network for root segmentation in trench profile *** defined two parameters,Depth50 and Width50,representing the vertical and horizontal centroid of root distribution,*** parameters for root distribution in rice(Oryza sativa L.)predicted by the trained model were highly correlated with parameters calculated by manual *** results indicated that this approach is useful for rapid quantification of the root distribution from the trench profile *** the trained model,we quantified the root distribution parameters among 60 rice accessions,revealing the phenotypic diversity of root *** conclude that employing the trench profile method and a convolutional neural network is reliable for root phenotyping and it will furthermore facilitate the study of crop roots in the field.

关键词： soil Root distribution

Effects of Mo and Zr on Microstructure,Mechanical Properties and Wear Resistance of Fe-Al Based Alloys

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Journal of Materials Science & technology 2008年第3期24卷 309-312页

作者： I.D.yeo H.S.Kim y.G.yoo W.y.Kim Advanced Materials R&D Division Korea Institute of Industrial Technology7-47Songdo-dongYeonsu-gu

In this work the microstructure, mechanical properties and wear resistance of Fe-Al based alloys with various alloying elements were studied. the microstructures were examined by optical and scanning electron microscopy （SEM） equipped with an energy dispersive X-ray spectroscope （EDS）. two types of alloys were prepared by vacuum arc melting. One is Fe-28Al based alloys （D03 structured） with and without alloying elements such as Mo and Zr. the other one is Fe-35Al based alloys （B2 structured） produced with the same manner. For both types of alloys, Mo addition had found to exhibit an equiaxed microstructure, while dendritic structure was observed to show the effect of Zr addition. these microstructural features were more evinced with increasing content of alloying element. Concerning the mechanical properties and wear resistance, Fe-35Al based alloys were superior to Fe-28Al based alloys over the whole temperature range investigated.

关键词： Fe-Al alloy Intermetallic Mechanical properties Wear resistance

Group classification for path equation describing minimum drag work and symmetry reductions

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Applied Mathematics and Mechanics(English Edition) 2010年第7期31卷 911-916页

作者： M.PAKDEMIRLI y.AKSOy Department of Mechanical Engineering Celal Bayar University

the path equation describing the minimum drag work first proposed by Pakdemirli is reconsidered （Pakdemirli, M. the drag work minimization path for a fly- ing object with altitude-dependent drag parameters. Proceedings of the Institution of Mechanical Engineers, Part C, Journal of Mechanical Engineering Science 223（5）, 1113- 1116 （2009））. the Lie group theory is applied to the general equation. the group classi- fication with respect to an altitude-dependent arbitrary function is presented. Using the symmetries, the group-invariant solutions are determined, and the reduction of order is performed by the canonical coordinates.

关键词： minimum drag work Lie group theory group classification