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C-Glycoside Synthesis Enabled by Nickel Catalysis

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Chinese Journal of Chemistry 2023年第17期41卷 2217-2236页

作者： Weidong Shang Rong Shi Dawen Niu Targeted Tracer Research and Development Laboratory Institute of Respiratory HealthState Key Laboratory of Biotherapy and Cancer Center West China Hospital and Schoolof Chemical EngineeringSichuan UniversityChengduSichuan 610041China State Key Laboratory of Biotherapy and Cancer Center West China Hospital and Department of Chemical EngineeringSichuan UniversityChengduSichuan 610041China

Comprehensive Summary,C-Glycosides are critical,naturally occurring products and medicinal candidates,and extensive efforts have been made to explore efficient approaches for creating C-glycosidic bonds.Transition-metal-catalysis,particularly nickel-catalyzed C-glycosylation reactions constitute a promising strategy.However,achieving a stereoselective synthesis ofα-andβ-C-glycosides has been a long-standing challenge.To address this problem,a variety of nickel-mediated strategies have been developed.This review highlights recent developments in the nickel-catalyzed diastereoselective C-glycosylation reactions and briefly summarizes the mechanistic understandings of these methods.

关键词： C-Glycosides Nickel Glycosylation Glycosyl radical Carbohydrates

The abundance of massive compact galaxies at 1.0

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Research in Astronomy and Astrophysics 2019年第10期19卷 109-120页

作者： shi-Ying Lu Yi-Zhou Gu Guan-Wen Fang Qi-rong Yuan Department of Physics and Institute of Theoretical Physics Nanjing Normal University Nanjing 210023 China Institute for Astronomy and History of Science and Technology Dali UniversityDali 671003 China

Based on a large sample of massive(M* 1010 M⊙) compact galaxies at 1.0 < z < 3.0 in five 3 D-HST/CANDELS fields, we quantify the fractional abundance and comoving number density of massive compact galaxies as a funct... 详细信息

Based on a large sample of massive(M* 1010 M⊙) compact galaxies at 1.0 shift. The samples of compact quiescent galaxies(cQGs) and compact star-forming galaxies(cSFGs) are constructed by various selection criteria of compact galaxies in the literature, and the effect of compactness definition on abundance estimate has proven to be remarkable,particularly for the cQGs and cSFGs at high redshifts. Regardless of the compactness criteria adopted,their overall redshift evolutions of fractional abundance and number density are found to be rather similar.Large samples of the cQGs exhibit a sustained increase in number density from z ~ 3 to 2 and a plateau at 1 shifts(z < 1) can be interpreted by the decrease of gas reservoirs in dark matter halos and the consequent low efficiency of gas-rich dissipation.

关键词： galaxies high-redshift-galaxies massive-compact-galaxies evolution-galaxies

The rice PLATZ protein SHORT GRAIN6 determines grain size by regulating spikelet hull cell division

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Journal of Integrative Plant Biology 2020年第6期62卷 847-864页

作者： shi-rong Zhou Hong-Wei Xue National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and Ecologythe Chinese Academy of SciencesShanghai 200032China State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research CenterNanjing Agricultural UniversityNanjing 210095China School of Agriculture and Biology Shanghai Jiao Tong UniversityShanghai 200240China

Grain size is a major determinant of cereal grain yields;however,the relevant regulatory mechanisms controlling this trait have not been fully elucidated.The rice(Oryza sativa)mutant short grain6(sg6)was identified based on its reduced grain length and weight.Here,we functionally characterized the role of SG6 in determining grain size through the regulation of spikelet hull cell division.SG6 encodes a previously uncharacterized plant ATrich sequence and zinc-binding(PLATZ)protein that is ubiquitously localized throughout the cell and is preferentially expressed in the early developing panicles but not in the endosperm.The overexpression of SG6 resulted in significantly larger and heavier grains,as well as increased plant heights,which is consistent with its elevated spikelet hull cell division rate.Yeast two-hybrid analyses revealed that SG6 interacts with the core cell cycle machinery DP protein and several other putative cell division regulators,consistent with our transcriptomic analysis,which showed that SG6 activates the expression of many DNA replication and cell-cycle-related genes.These results confirm the crucial role of SG6 in determining grain size by regulating spikelet hull cell division and provide clues for understanding the functions of PLATZ family proteins and the network regulating cereal grain size.

关键词： sativa) fir cereal

Disruption of key GTPase regulators of endocytic recycling compartment does not interfere with soluble antigen crosspresentation in dendritic cells

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Cellular & Molecular Immunology 2016年第4期13卷 554-556页

作者： Hua rong Yan shi Department of Basic Medical Sciences School of Medicine Tsinghua-Peking Center for Life Sciences Tsinghua University Beijing China Department of Microbiology Immunology & Infectious Diseases and Snyder Institute University of Calgary Calgary Alberta Canada

Crosspresentation is of vital significance to immune surveillance. External antigens, soluble or solid, enter cells via endophagocytic vesicles and are eventually delivered to MHC class I molecules on the cell surface. After antigen uptake, there are three proposed pathways leading to surface MHC class I/peptide complex presentation.

关键词： GTP磷酸水解酶类树突细胞胰岛素主要组织相容性复合物自然资源保护

Main Beam Pointing and Null Constraint Optimization for Satellite Navigation Nulling Antenna

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Main Beam Pointing and Null Constraint Optimization for Sate...

Multipurpose Satellite Navigation Receiver with Three Antennas Amplitude Comparison DF Based on Baseband Information Fusion

第九届中国卫星导航学术年会

作者： Rong Shi Science and Technology on Electronic Information Control Laboratory

The power inversion algorithm is usually adopted in the traditional satellite navigation nulling antenna. The null can be formed on the direction of jamming with high power so as to decrease its power into the navigation receiver. The anti-jamming is realized, but receiving performances for navigation satellite signals have not been considered at all in above methods. In this paper, the published navigation satellite almanac and the parameters output from INS in the platform are fully utilized. The direction of signal arrival about each currently visible navigation satellite can be calculated in real time in the nulling antenna coordinate system. According to the LCMP(Linear Constrained Minimum Power) algorithm, the main beam pointing condition is restricted for each visible satellite in order to improve the receiving antenna gain for this direction. This is the first beam forming optimization. Then under the condition that the nulling freedom degree is within the allowable range, the null constraint conditions of antenna beams are imposed to the direction of other navigation satellites signals, in which the antenna gain are relatively larger in the firstly beam forming. This is the second beam forming optimization in order to reduce the multiple access interference of CMDA system. Through above two optimizations, it greatly reduces the external oppressive jamming and mutual interference between different navigation satellites. Finally, the feasibility and availability of this method are verified by simulations. It is an important reference for the improvement of anti-jamming performance and engineering application for satellite navigation nulling antenna.

关键词： satellite navigation nulling antenna almanac INS main beam pointing constraint null constraint oppressive jamming CDMA interference

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Multipurpose Satellite Navigation Receiver with Three Antenn...

New insights of CYP1A in endogenous metabolism: a focus on single nucleotide polymorphisms and diseases

第十三届中国卫星导航年会

作者： Rong Shi Junhao Chen Da Ma Science and Technology on Electronic Information Control Laboratory

The traditional satellite navigation receiver with multi antennas forming long baselines is based on carrier phase difference measurement for DF（Direction Finding）. It has many problems, such as cumbersome baseline calibration, complex phase ambiguity removing algorithm and high application cost. A new satellite navigation receiver with three antennas amplitude comparison DF based on baseband information fusion is designed in this paper. Its working principle, parameter optimization, and solution to DF are described in detail. Through associated baseband information, the parameters guidance for each channel to receive the navigation signal is realized for rapid acquisition and tracking. DF is completed by measuring the carrier to noise power ratio of signals from different antennas for the same navigation satellite. Finally, a prototype system is developed by using the commercial satellite navigation receiving antennas, and experiments are carried out for the actual navigation signals to verify the effectiveness of the design. This kind of receiver not only has many uses, such as attitude measurement, DF for navigation signals, and antideception based on DF information, but also shows many advantages, such as high antenna integration, small installation spaces, convenient use and high performance. So it will have wide application in the future.

关键词： Multipurpose Satellite Navigation Receiver Three Antennas Amplitude Comparison Direction Finding Signal Carrier To Noise Power Ratio Baseband Information Fusion Attitude Measurement Anti-deception

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Acta Pharmaceutica Sinica B 2020年第1期10卷 91-104页

作者： Jian Lu Xuyang Shang Weiguo Zhong Yuan Xu Rong Shi Xin Wang Changning Maternity and Infant Health Hospital East China Normal UniversityShanghai 200051China Shanghai Key Laboratory of Regulatory Biology Institute of Biomedical Sciences and School of Life SciencesEast China Normal UniversityShanghai 200241China Department of Pharmacology Shanghai University of Traditional Chinese MedicineShanghai 201203China

Cytochrome P4501A(CYP1A),one of the major CYP subfamily in humans,not only metabolizes xenobiotics including clinical drugs and pollutants in the environment,but also mediates the bio transformation of important endogenous substances.In particular,some single nucleotide polymorphisms(SNPs)for CYPIA genes may affect the metabolic ability of endogenous substances,leading to some physiological or pathological changes in humans.This review first summarizes the metabolism of endogenous substances by CYPIA,and then introduces the research progress of CYPIA SNPs,especially the research related to human diseases.Finally,the relationship between SNPs and diseases is discussed.In addition,potential animal models for CYPIA gene editing are summarized.In conclusion,CYP1A plays an important role in maintaining the health in the body.

关键词： CYP1A Endogenous substances Xenobiotics SNPs Metabolism and disease

Platform Attitude Measurement Technology by Single Antenna Navigation Receiver Fused with Electronic Reconnaissance DF

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Platform Attitude Measurement Technology by Single Antenna N...

Tailoring Texture to Highly Strengthen AZ31 Alloy Plate in the Thickness Direction via Pre-tension and Rolling-Annealing

第十三届中国卫星导航年会

作者： Rong Shi Junhao Chen Jiang Liu Science and Technology on Electronic Information Control Laboratory

Accurate attitude measurement on the electronic reconnaissance aircraft, ship and other platform is the necessary prerequisite for electronic reconnaissance tasks. The traditional method depends on the inertial navigation or GNSS attitude instrument with multi antennas. In addition, for platforms with the electronic reconnaissance and DF（Direction Finding） equipment, their DF capability can be fully utilized. Through the phase difference measurement among signals in interferometer channels based on codeless phase discrimination in frequency domain, combined with the positioning and velocity measurement results from the single antenna satellite navigation receiver, and using the Doppler frequency shift difference of each navigation signal to realize signal separation and direction matching, three attitude parameters of the platform, such as heading, pitch and roll angle can be measured. Finally, the correctness and effectiveness of this method are verified by the analysis and processing on the actual signal from the electronic reconnaissance receiver. This method makes full use of the functionality of the existing hardware platform. It does not add new hardware modules, and only needs to be upgraded in the software. So it explores a new way for the attitude measurement on the electronic reconnaissance platform.

关键词： Single Antenna Navigation Receiver Electronic Reconnaissance Direction Finding By Interferometer Platform Attitude Measurement Doppler Frequency Difference Codeless Phase Discrimination In Frequency Domain

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Acta Metallurgica Sinica(English Letters) 2023年第2期36卷 266-280页

作者： Tianjiao Li Jiang Zheng Lihong Xia Haoge Shou Yongfa Zhang Rong Shi Liuyong He Wenkai Li International Joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringChongqing UniversityChongqing400044China Shenyang National Laboratory for Materials Science Chongqing UniversityChongqing400044China College of Mechanical Engineering Chongqing Technology and Business UniversityChongqing400067China Zhejiang Provincial Engineering Center of Integrated Manufacturing Technology and Intelligent Equipment Zhejiang University City CollegeHangzhou310015China

Conventional wrought Mg alloys,such as AZ31 and ZK60 rolled plates,usually exhibit significantly low tensile yield strength in the thickness direction.This can be attributed to the high activity of{10-12}tension twinning due to the strong basal texture(//ND,normal direction).In this work,the tensile yield strength in the ND of the as-rolled(AR)AZ31 plate increased from 50 to 150 MPa(increased by 200%)via simple processing,i.e.,pre-tension and rolling-annealing(PTRA)treatment.The strong basal texture(//ND)of the AR plate was changed into a weakened fiber texture(⊥ND).The evolution of microstructures during PTRA treatment and the activated deformation modes during uniaxial tension were studied quantitatively and statistically by the means of intergranular misorientation(IM)and in-grain misorientation axes(IGMA)analysis.The results indicate that various twin variants,as well as{10-12}-{10-12}secondary twins,were activated during pre-tension and rolling,and most residual matrix was consumed by twins after annealing.The dominated deformation modes in tension changed from{10-12}tension twinning(the AR sample)to prismatic slip(the PTRA sample)in the early tensile deformation.The underlying formation mechanism of the fiber texture and corresponding strengthening mechanism were discussed.

关键词： Pre-tension Annealing Tailoring texture Texture strengthening Deformation modes