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| 1 | 综合性学术搜索引擎研究显示文摘选择了四种当前国外典型的可免费使用的综合性学术搜索引擎Google Scholar、Scir-us、BASE、Athenus进行了研究,分析了各自的特色,对比了它们的资源覆盖范围、检索功能和检索效果,提出了当前这类学术搜索引擎存在的主要问题:资源的学术质量问题、检索结果的归并与去重问题、相关性排序问题。在此基础上,探讨了其对图书情报机构、用户和资源供应商的有利和不利的影响。 | 常唯 | 2007 | 大学图书馆学报2007，25，2： | 31 |
| 2 | Interpolation mechanism of fuzzy control显示文摘The fuzzy control algorithms used commonly at present are all regarded as some interpolation functions, which is in essence equivalent to discrete response functions to be fitted. This means that fuzzy control method is similar to finite element method in mathematical physics, which is a kind of direct manner or numerical method in control systems. | 李洪兴 | 1998 | Science China(Technological Sciences)1998，41，3： | 32 |
| 3 | Genome Engineering in Rice Using Cas9 Variants that Recognize NG PAM Sequences显示文摘CRISPR/Cas9 genome editing relies on sgRNA-target DNA base pairing and a short downstream PAM sequence to recognize target DNA. The strict protospacer adjacent motif (PAM) requirement hinders applications of the CRISPR/Cas9 system since it restricts the targetable sites in the genomes. xCas9 and SpCas9-NG are two recently engineered SpCas9 variants that can recognize more relaxed NG PAMs, implying a great potential in addressing the issue of PAM constraint. Here we use stable transgenic lines to evaluate the efficacies of xCas9 and SpCas9-NG in performing gene editing and base editing in rice. We found that xCas9 can efficiently induce mutations at target sites with NG and GAT PAM sequences in rice. However, base editors containing xCas9 failed to edit most of the tested target sites. SpCas9-NG exhibited a robust editing activity at sites with various NG PAMs without showing any preference for the third nucleotide after NG. Moreover, we showed that xCas9 and SpCas9-NG have higher specificity than SpCas9 at the CGG PAM site. We further demonstrated that different forms of cytosine or adenine base editors containing SpCas9-NG worked efficiently in rice with broadened PAM compatibility. Taken together, our work has yielded versatile genome-engineering tools that will significantly expand the target scope in rice and other crops. | Kai Hua Xiaoping Tao Peijin Han Rui Wang Jian-Kang Zhu | 2019 | Molecular Plant2019，12，7： | 22 |
| 4 | Versatile Nucleotides Substitution in Plant Using an Improved Prime Editing System显示文摘Dear Editor,Base editors(BEs)based on the CRISPR/Cas9 system,including cytosine base editors and adenine base editors,which can efficiently perform four transition mutations(C·G-to-T·A and A·T-to-G·C),have been well studied and widely used to produce base mutations in a variety of organisms,including in plants such as rice. | Wen Xu Chengwei Zhang Yongxing Yang Si Zhao Guiting Kang Xiaoqing He Jinling Song Jinxiao Yang | 2020 | Molecular Plant2020，13，5： | 20 |
| 5 | Grinding temperature and energy ratio coefficient in MQL grinding of high-temperature nickel-base alloy by using different vegetable oils as base oil显示文摘Vegetable oil can be used as a base oil in minimal quantity of lubrication(MQL). This study compared the performances of MQL grinding by using castor oil, soybean oil, rapeseed oil, corn oil, sunflower oil, peanut oil, and palm oil as base oils. A K-P36 numerical-control precision surface grinder was used to perform plain grinding on a workpiece material with a high-temperature nickel base alloy. A YDM–III 99 three-dimensional dynamometer was used to measure grinding force,and a clip-type thermocouple was used to determine grinding temperature. The grinding force, grinding temperature, and energy ratio coefficient of MQL grinding were compared among the seven vegetable oil types. Results revealed that(1) castor oil-based MQL grinding yields the lowest grinding force but exhibits the highest grinding temperature and energy ratio coefficient;(2) palm oil-based MQL grinding generates the second lowest grinding force but shows the lowest grinding temperature and energy ratio coefficient;(3) MQL grinding based on the five other vegetable oils produces similar grinding forces, grinding temperatures, and energy ratio coefficients, with values ranging between those of castor oil and palm oil;(4) viscosity significantly influences grinding force and grinding temperature to a greater extent than fatty acid varieties and contents in vegetable oils;(5) although more viscous vegetable oil exhibits greater lubrication and significantly lower grinding force than less viscous vegetable oil, high viscosity reduces the heat exchange capability of vegetable oil and thus yields a high grinding temperature;(6) saturated fatty acid is a more efficient lubricant than unsaturated fatty acid; and(7) a short carbon chain transfers heat more effectively than a long carbon chain. Palm oil is the optimum base oil of MQL grinding, and this base oil yields 26.98 N tangential grinding force,87.10 N normal grinding force, 119.6 °C grinding temperature, and 42.7% energy ratio coefficient. | Li Benkai Li Changhe Zhang Yanbin Wang Yaogang Jia Dongzhou Yang Min | 2016 | Chinese Journal of Aeronautics2016，29，4： | 20 |
| 6 | Perspectives on the Application of Genome-Editing Technologies in Crop Breeding显示文摘Most conventional and modern crop-improvement methods exploit natural or artificially induced genetic variations and require laborious characterization of the progenies of multiple generations derived from time-consuming genetic crosses.Genome-editing systems,in contrast,provide the means to rapidly modify genomes in a precise and predictable way,making it possible to introduce improvements directly into elite varieties.Here,we describe the range of applications available to agricultural researchers using existing genome-editing tools.In addition to providing examples of genome-editing applications in crop breeding,we discuss the technical and social challenges faced by breeders using genome-editing tools for crop improvement. | Kai Hua Jinshan Zhang Jose Ramon Botella Changle Ma Fanjiang Kong Baohui Liu Jian-Kang Zhu | 2019 | Molecular Plant2019，12，8： | 19 |
| 7 | Manipulating mRNA splicing by base editing in plants显示文摘Precursor-mRNAs(pre-mRNA) can be processed into one or more mature m RNA isoforms through constitutive or alternative splicing pathways. Constitutive splicing of pre-mRNA plays critical roles in gene expressional regulation, such as intronmediated enhancement(IME), whereas alternative splicing(AS) dramatically increases the protein diversity and gene functional regulation. However, the unavailability of mutants for individual spliced isoforms in plants has been a major limitation in studying the function of mRNA splicing. Here, we describe an efficient tool for manipulating the splicing of plant genes. Using a Cas9-directed base editor, we converted the 5′ splice sites in four Arabidopsis genes from the activated GT form to the inactive AT form. Silencing the AS of HAB 1.1(encoding a type 2 C phosphatase) validated its function in abscisic acid signaling, while perturbing the AS of RS31 A revealed its functional involvement in plant response to genotoxic treatment for the first time. Lastly,altering the constitutive splicing of Act2 via base editing facilitated the analysis of IME. This strategy provides an efficient tool for investigating the function and regulation of gene splicing in plants and other eukaryotes. | Chenxiao Xue Huawei Zhang Qiupeng Lin Rong Fan Caixia Gao | 2018 | Science China(Life Sciences)2018，61，11： | 18 |
| 8 | Cas9-NG Greatly Expands the Targeting Scope of the Genome-Editing Toolkit by Recognizing NG and Other Atypical PAMs in Rice显示文摘CRISPR technologies enabling precise genome manipulation are valuable for gene function studies and molecular crop breeding. However, the requirement of a protospacer adjacent motif (PAM)y such as NGG and TTN, for Cas protein recognition restricts the selection of targetable genomic loci in practical applications of CRISPR technologies. Recently Cas9-NG, which recognizes a minimal NG PAM, was reported to expand the targeting space of genome editing in human cells, but it remains unclear whether this Cas9 variant can be used in plants. In this study, we evaluated the nuclease activity of Cas9-NG toward various NGN PAMs by targeting endogenous genes in transgenic rice. We found that Cas9-NG edits all NGG, NGA, NGT, and NGC sites with impaired activity, while the gene-edited plants were dominated by monoallelic mutations. Cas9-NG-engineered base editors were then developed and used to generate O s B Z R I gainof- function plants that can not be created by other available Cas9-engineered base editors. Moreover, we showed that a Cas9-NG-based transcriptional activator efficiently upregulated the expression of endogenous target genes in rice. In addition, we discovered that Cas9-NG recognizes NAC, NTG, NTT, and NCG apart from NG PAM. Together, these findings demonstrate that Cas9-NG can greatly expand the targeting scope of genome-editing tools, showing great potential for targeted genome editing, base editing, and genome regulation in plants. | Bin Ren Lang Liu Shaofang Li Yongjie Kuang Jingwen Wang Dawei Zhang Xueping Zhou Honghui Lin Huanbin Zhou | 2019 | Molecular Plant2019，12，7： | 18 |
| 9 | ON THE STRICT EFFICIENCY IN A LOCALLYCONVEX SPACE显示文摘In this paper, a new concept, strictly efficient points in locally convex spaces,is introduced, and scalar characterization of a strictly efficient point is established. Furthermore, we study the best approximation property for a strictly efficient point by an equivalent norm. | FU Wantao (Department of Mathematics, Nanchang University, Nanchang 330047, China)CHENG Yonghong (Institute of Systems Science, Acadetnia Sinica, Beijing 100080, China) | 1999 | Systems Science and Mathematical Sciences1999，12，1： | 17 |
| 10 | Gene editing in plants:progress and challenges显示文摘The clustered regularly interspaced short palindromic repeat(CRISPR)-associated protein 9(Cas9)genome editing system is a powerful tool for targeted gene modifications in a wide range of species,including plants.Over the last few years,this system has revolutionized the way scientists perform genetic studies and crop breeding,due to its simplicity,flexibility,consistency and high efficiency.Considerable progress has been made in optimizing CRISPR/Cas9 systems in plants,particularly for targeted gene mutagenesis.However,there are still a number of important challenges ahead,including methods for the efficient delivery of CRISPR and other editing tools to most plants,and more effective strategies for sequence knock-ins and replacements.We provide our viewpoint on the goals,potential concerns and future challenges for the development and application of plant genome editing tools. | Yanfei Mao Jose Ramon Botella Yaoguang Liu Jian-Kang Zhu | 2019 | National Science Review2019，6，3： | 17 |
| 11 | Bioinspired Adhesive and Antibacterial Microneedles for Versatile Transdermal Drug Delivery显示文摘Microneedles have attracted increasing interest among various medical fields due to their painless,noninvasive,and efficient way of drug delivery.However,practical applications of these microneedles in different epidermal locations and environments are still restricted by their low adhesion and poor antimicrobial activity.Here,inspired by the antibacterial strategy of Paenibacillus polymyxa and adhesion mechanisms of mussel byssi and octopus tentacles,we develop hierarchical microneedles with multifunctional adhesive and antibacterial abilities.With polydopamine hydrogel as the microneedle base and a loop of suctioncup-structured concave chambers encircling each microneedle,the generated microneedles can fit the skin well;keep strong adhesion in dry,moist,and wet environments;and realize self-repair after being split into two parts.Besides,as polymyxin is loaded into both the hydrogel tips and the polydopamine base,the microneedles are endowed with excellent ability to resist common bacteria during storage and usage.We have demonstrated that these microneedles not only showed excellent adhesion when applied to knuckles and ideal antibacterial activity but also performed well in drug-sustained release and treatment for the osteoarthritis rat model.These results indicate that bioinspired multifunctional microneedles will break through the limitation of traditional methods and be ideal candidates for versatile transdermal drug delivery systems. | Xiaoxuan Zhang Guopu Chen Yunru Yu Lingyu Sun Yuanjin Zhao | 2020 | Research2020，，1： | 14 |
| 12 | Improving Plant Genome Editing with High-Fidelity xCas9 and Non-canonical PAM-Targeting Cas9-NG显示文摘Two recently engineered SpCas9 variants, namely xCas9 and Cas9-NG, show promising potential in improving targeting specificity and broadening the targeting range. In this study, we evaluated these Cas9 variants in the model and crop plant, rice. We first tested xCas9-3.7, the most effective xCas9 variant in mammalian cells, for targeted mutagenesis at 16 possible NGN PAM (protospacer adjacent motif) combinations in duplicates. xCas9 exhibited nearly equivalent editing efficiency to wild-type Cas9 (Cas9-WT) at most canonical NGG PAM sites tested, whereas it showed limited activity at non-canonical NGH (H = A, C, T) PAM sites. High editing efficiency of xCas9 at NGG PAMs was further demonstrated with C to T base editing by both rAPOBECI and PmCDAI cytidine deaminases. With mismatched sgRNAs, we found that xCas9 had improved targeting specificity over the Cas9-WT. Furthermore, we tested two Cas9-NG variants, Cas9-NGv1 and Cas9-NG, for targeting NGN PAMs. Both Cas9-NG variants showed higher editing efficiency at most non-canonical NG PAM sites tested, and enabled much more efficient editing than xCas9 at AT-rich PAM sites such as GAT, GAA, and CAA. Nevertheless, we found that Cas9-NG variants showed significant reduced activity at the canonical NGG PAM sites. In stable transgenic rice lines, we demonstrated that Cas9-NG had much higher editing efficiency than Cas9-NGv1 and xCas9 at NG PAM sites. To expand the base-editing scope, we developed an efficient C to T base-editing system by making fusion of Cas9-NG nickase (D10A version), PmCDAI, and UGI. Taken together, our work benchmarked xCas9 as a high-fidelity nuclease for targeting canonical NGG PAMs and Cas9-NG as a preferred variant for targeting relaxed PAMs for plant genome editing. | Zhaohui Zhong Simon Sretenovic Qiurong Ren Lijia Yang Yu Bao Caiyan Qi Mingzhu Yuan Yao He Shishi Liu Xiaopei Liu Jiaheng Wang Lan Huang Yan Wang Dibin Baby David Wang Tao Zhang Yiping Qi Yong Zhang | 2019 | Molecular Plant2019，12，7： | 13 |
| 13 | Toward Precision Genome Editing in Crop Plants显示文摘Precision genome editing through homology-directed repair(HDR)in plants remains very challenging due to the innately low occurrence of HDR and obstacles in the delivery of sufficient donor repair template(DRT)into plant cells.For single-base substitution,cytidine or adenine base editors have been used successfully in crop plants in recent years.However,base editing is constrained by the distance between the targeted base and PAM motif and cannot install predefined transversion mutations or insertions and deletions(indels).Here,we briefly summarize the strategies reported so far for precision genome editing in plants.Based on the recently developed prime editing strategy,which enables gene replacement without double-strand breaks(DSBs)or DRT in both human cells and plants,we provide our perspectives on exploiting diverse strategies to achieve precise targeted gene/allele replacement toward crop improvement and resilience for sustainable agricultural development. | Jingying Li Huiyuan Li Jilin Chen Lei Yan Lanqin Xia | 2020 | Molecular Plant2020，13，6： | 13 |
| 14 | The study of neighboring nucleotide composition and transition/transversion bias显示文摘Base substitution is one of the raw fuels that produce genetic variation and drive evolu-tion. Recent studies have shown that the genome components affect mutation patterns to some extent. In order to infer the correlation between the Transition/Transversion ratio (Ts/Tv) and the number of immediately adjacent A&T nucleotides, we investigated 3611007 Oryza sativa SNPs (including 45462 coding SNPs, and 242811 intronic SNPs) and 32019 Arabidopsis SNPs. The results show that Ts/Tv is negatively correlated with the number of immediately adjacent A&T in O. sativa and Arabidopsis. We further calculated AT2 (the number of SNPs whose immediately adjacent nucleotides are either A or T) and AT0 (the number of SNPs whose immediately adjacent nucleotides are either C or G) for all 6 types of SNPs. C/G SNP of O. sativa and Arabidopsis has the highest AT2/AT0, which denotes C/G SNP may be influenced by the adjacent A&T nucleotides mostly. For SNPs in O. sativa, the neighboring effect of A&T nucleotides is limited to 2 nucleotides on both sides; for SNPs in Arabidop-sis, the effect extends no more than 4 nucleotides on both sides. | ZHAO Hui1,3*, LI Qizhai1,2,3*, LI Jun1, ZENG Changqing1, HU Songnian1 & YU Jun1 1. Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100030, China 2. Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100080, China 3. Graduate University of Chinese Academy of Sciences, Beijing 100039, China | 2006 | Science China(Life Sciences)2006，49，4： | 12 |
| 15 | Microstructure of Laser Remelted Ni-base Alloy Coating on Stainless Steel显示文摘A 5 kW CW CO2 gas laser was used to produce NiCrBSi superalloy coatings. Powders were preplaced by plasma-spraying. The microstructure and chemical composition of the coating have been studied by SEM, XRD and HREM. The results show the coating microstructure is fine dendrites, composed of γ matrix, γ’ and boride (NiB) eutectic, the lattice parameter of the γ matrix is 0.3572 nm and there is a metallurgical bonding in interface. | Gao, Y Liang, Y Shi, CX | 1998 | Journal of Materials Science & Technology1998，14，1： | 11 |
| 16 | Performance of sand and shredded rubber tire mixture as a natural base isolator for earthquake protection显示文摘The performance of a well-designed layer of sand, and composites like layer of sand mixed with shredded rubber tire(RSM) as low cost base isolators, is studied in shake table tests in the laboratory. The building foundation is modeled by a 200 mm by 200 mm and 40 mm thick rigid plexi-glass block. The block is placed in the middle of a 1m by 1m tank filled with sand. The selected base isolator is placed between the block and the sand foundation. Accelerometers are placed on top of the footing and foundation sand layer. The displacement of the footing is also measured by LVDT. The whole setup is mounted on a shake table and subjected to sinusoidal motions with varying amplitude and frequency. Sand is found to be effective only at very high amplitude(> 0.65 g) of motions. The performance of a composite consisting of sand and 50% shredded rubber tire placed under the footing is found to be most promising as a low-cost effective base isolator. | Srijit Bandyopadhyay Aniruddha Sengupta G.R.Reddy | 2015 | Earthquake Engineering and Engineering Vibration2015，14，4： | 10 |
| 17 | Durability and microstructure analysis of the road base material prepared from red mud and flue gas desulfurization fly ash显示文摘The present study aimed to investigate the durability and microstructure evolution of road base materials(RBM)prepared from red mud and flue gas desulfurization fly ash.The durability testing showed that the strength of RBM with the blast furnace slag addition of 1wt%,3wt%and 5wt%reached 3.81,4.87,and 5.84 MPa after 5 freezing–thawing(F–T)cycles and reached 5.21,5.75,and 6.98 MPa after 20 weting–drying(W–D)cycles,respectively.The results also indicated that hydration products were continuously formed even during W–D and F–T exposures,resulting in an increase of the strength and durability of RBM.The observed increase of macropores(>1μm)after F–T and W–D exposures suggested that the mechanism of RBM deterioration is pore enlargement due to cracks that develop inside their matrix.Moreover,the F–T exposure showed a greater negative effect on the durability of RBM compared to the W–D exposure.The leaching tests showed that sodium and heavy metals were solidified below the minimum requirement,which indicates that these wastes are suitable for use as a natural material replacement in road base construction. | Emile Mukiza Ling-ling Zhang Xiao-ming Liu | 2020 | International Journal of Minerals,Metallurgy and Materials2020，27，4： | 10 |
| 18 | Research on SINS Alignment Algorithm Based on FIR Filters显示文摘An inertial frame based alignment (IFBA) method is presented, especially for the applications on a rocking platform, e.g., marine applications. Defining the initial body frame as the inertial frame, the IFBA method achieves the alignment by virtue of a cascade of low-pass FIR filters, which attenuate the disturbing acceleration and maintain the gravity vector. The aligning time rests with the orders of the FIR filter group, and the method is suitable for large initial misalignment case. An alignment scheme comprising a coarse phase by the IFBA method and a fine phase by a Kalman filter is presented. Both vehicle-based and ship-based alignment experiments were carried out. The results show that the proposed scheme converges much faster than the traditional method at no cost of precision and also works well under any large initial misalignment. | 练军想 胡德文 武元新 胡小平 | 2007 | Journal of Beijing Institute of Technology2007，16，4： | 10 |
| 19 | Use of Selection Indices Based on Multivariate Analysis for Improving Grain Yield in Rice | Hossein SABOURI Babak RABIEI Maryam FAZLALIPOUR | 2008 | Rice science2008，15，4： | 9 |
| 20 | Machine learning assisted design of γ′-strengthened Co-base superalloys with multi-performance optimization显示文摘Designing a material with multiple desired properties is a great challenge,especially in a complex material system.Here,we propose a material design strategy to simultaneously optimize multiple targeted properties of multi-component Co-base superalloys via machine learning.The microstructural stability,γ′solvus temperature,γ′volume fraction,density,processing window,freezing range,and oxidation resistance were simultaneously optimized. | Pei Liu Haiyou Huang Stoichko Antonov Cheng Wen Dezhen Xue Houwen Chen Longfei Li Qiang Feng Toshihiro Omori Yanjing Su | 2020 | npj Computational Materials2020，，1： | 8 |
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