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Agricultural Sciences in China 2011年第1期10卷 49-57页

作者： LU Zhen-hua ZHOU zhi-qin XIE Rang-jin College of Horticulture and Landscape Architecture Southwest University Chongqing 400716 P.R.China Citrus Research Institute Chinese Academy of Agricultural Sciences/Southwest University Chongqing 400712 P.R.China Zhengzhou Fruit Research Institute Chinese Academy of Agricultural Sciences Zhengzhou 450009 P.R. China

The genus Citrus L. has a long controversial taxonomy history, and a well-resolved molecular phylogeny of the ＂true citrus fruit trees＂ group in the future will provide new information for advancing breeding techniques and developing better conservation strategies. In the present study, three cpDNA fragments （TrnL-TrnF, PsbH-PetB, and TrnS-TrnG） of 30 genotypes chosen from the six genera of the ＂true citrus fruit trees＂ group were analyzed. A molecular phylogenetic tree of the ＂true citrus fruit trees＂ group ＂~as reconstructed based on plastid DNA sequences. The results confirmed that the ＂true citrus fruit trees＂ group was monophyletic, and thereby the group was divided into genera as previously suggested based on morphological characters. The cpDNA data also suggested that Poncirus might be the first genus separated from the other five genera in the group. The genus Fortunella were of hybrid origin and Citrus might be as its putative paternal parent. The genera Microcitrus, Eremocitrus, and Clymenia were possibly monophyletic and their common ancestor might branch out from Citrus. Furthermore, the phylogenetic relationships within the Citrus genus were discussed.

关键词： Rutaceae Aurantioideae true citrus fruit trees group molecular phylogenetics cpDNA sequence

On a Conjecture of Bahri–Xu

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Acta Mathematica Sinica,English Series 2021年第11期37卷 1721-1742页

作者： Hong CHEN Jian Quan GE Kai JIA zhi qin LU School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China School of Mathematical Sciences Laboratory of Mathematics and Complex SystemsBeijing Normal UniversityBeijing 100875P.R.China Department of Mathematics University of CaliforniaIrvineIrvineCA 92697USA

In order to study the Yamabe changing-sign problem,Bahri and Xu proposed a conjecture which is a universal inequality for p points in R^(m).They have verified the conjecture for p≤*** this paper,we first simplify this conjecture by giving two sufficient and necessary conditions *** we prove the conjecture for the basic case m=1 with arbitrary *** addition,for the cases when p=4,5 and m≥2,we manage to reduce them to the basic case m=1 and thus prove them as well.

关键词： Yamabe problem Bahri-Xu Conjecture

Direction-of-Arrival Method Based on Randomize-Then-Optimize Approach

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Journal of Electronic Science and Technology 2022年第4期20卷 416-424页

作者： Cai-Yi Tang Sheng Peng zhi-qin Zhao Bo Jiang Science and Technology on Electronic Information Control Laboratory Chengdu 610036 School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731 54th Research Institute of China Electronics Technology Group Shijiazhuang 050081

The direction-of-arrival(DOA)estimation problem can be solved by the methods based on sparse Bayesian learning(SBL).To assure the accuracy,SBL needs massive amounts of snapshots which may lead to a huge computational *** order to reduce the snapshot number and computational complexity,a randomize-then-optimize(RTO)algorithm based DOA estimation method is ***“learning”process for updating hyperparameters in SBL can be avoided by using the optimization and Metropolis-Hastings process in the RTO *** apply the RTO algorithm for a Laplace prior,a prior transformation technique is *** demonstrate the effectiveness of the proposed method,several simulations are proceeded,which verifies that the proposed method has better accuracy with 1 snapshot and shorter processing time than conventional compressive sensing(CS)based DOA methods.

关键词： Compressive sensing(CS) randomize-then-optimize(RTO) single snapshot sparse signal reconstruction

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基于区块链的医疗数据分类加密共享方案

应用科学学报 2024年第4期42卷 613-628页

作者：夏晓亮秦智万武南张仕斌张金全成都信息工程大学网络空间安全学院四川成都610225 成都信息工程大学先进密码技术与系统安全四川省重点实验室四川成都610225

针对医疗数据共享时,存在共享数据多于需求数据,以及加密大量元数据会产生较大的计算开销问题,提出一种基于区块链的医疗数据分类加密共享方案,结合基于属性的加密和区块链实现对医疗数据的访问控制和数据共享。首先,按照基本信息、医... 详细信息

针对医疗数据共享时,存在共享数据多于需求数据,以及加密大量元数据会产生较大的计算开销问题,提出一种基于区块链的医疗数据分类加密共享方案,结合基于属性的加密和区块链实现对医疗数据的访问控制和数据共享。首先,按照基本信息、医疗科室、疾病类型将完整医疗数据分类划分为医疗元数据,对数据进行细粒度访问控制。其次,提出数据访问策略分类算法,将数据访问策略划分为属性加密策略和区块链访问策略,合并多个元数据的属性加密策略用以降低基于属性加密时构建访问结构树的计算开销;智能合约依据区块链访问策略对链上数据进行访问控制,并通过修改区块链策略实现权限撤销。最后,通过安全性分析和仿真实验表明该方案具有可行性和较高的效率。

关键词：区块链属性基加密智能合约访问控制数据共享

A V-shaped spectroscopic cell for FTIR measurements

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Chinese Chemical Letters 2011年第4期22卷 481-484页

作者： Xiang qin Lin zhi Xiang Zhang Wan Qun Hu Department of Chemistry University of Science and Technology of China Hefei 230026 China

A V-shaped spacroscopic cell（V-cell） was constructed using two CaF2 optical plates for FTIR light transparent measurements in the range of 4000-1000 cm^（-1）.The spectrum of ethanol was characterized with the standard spectra,excellent fitting was achieved with a bottom-width correction *** principle of the V-cell was discussed,giving equations for the data *** shows that the V-cell is an auto-focus type spectroscopic cell,which can effectively avoid absorption saturation with amplifications for weak absorption *** V-cell design is simple and effective,easy to operate,suitable for applications in liquid samples with high absorption bands,willing to have broad application prospects.

关键词： V-shaped cell FTIR spectroscopy Light transparent Error correction Demountable Ethanol

New Approach to Cluster Synchronization in Complex Dynamical Networks

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Communications in Theoretical Physics 2009年第3期51卷 485-489页

作者： LU Xin-Biao qin Bu-zhi LU Xin-Yu Department of Automation Hohai University Nanjing 210098 China Department of Automation Nanjing College of Chemical Technology Nanjing 210048 China Shandong Metallurgical Research Institute Jinan 250014 China

In this paper, a distributed control strategy is proposed to make a complex dynamical network achieve cluster synchronization, which means that nodes in the same group achieve the same synchronization state, while nodes in different groups achieve different synchronization states. The local and global stability of the cluster synchronization state are analyzed. Moreover, simulation results verify the effectiveness of the new approach.

关键词： cluster synchronization complex network distributed control strategy

Synthesis and Antitumor Activity of 4-tert-Butyl-5-benzyl-2-benzyliminothiazoles

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Chemical Research in Chinese Universities 2014年第1期30卷 49-54页

作者： YE Jiao QIU Shenyi HU Aixi PENG Junmei qin zhi College of Chemistry and Chemical Engineering Hunan University Changsha 410082 P. R. China

A series of novel Schiff bases including 4-tert-butyl-5-benzyl-2-benzyliminothiazoles was synthesized by reacting the aromatic aldehydes with the corresponding *** antitumor bioassay revealed that compounds 2n and 2m exhibited potent cytotoxicity against human cervix cancer（HeLa） cell line with IC50 values of 0.001 and 0.007 mmol/L,*** preliminary structure-activity relationship（SAR） investigations and the apoptosis evaluation suggest that 4-tert-butyl-5-benzyl-2-benzyliminothiazoles may be a satisfactory backbone for antitumor activity,and compound 2n can serve as an attractive candidate for the development of novel apoptosis in anticancer treatment.

关键词： 2-Aminothiazole Schiff base Antitumor activity

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双路输出的反激式变换器拓扑及特性研究

电力电子技术 2024年第10期58卷 93-96页

作者：秦志强张波严宗周华南理工大学电力学院广东广州510640 深圳讴艾半导体有限公司广东深圳518000

此处提出了一种双路输出的反激式变换器拓扑,该拓扑只需要一个输出绕组就可以实现双路输出,相比传统的通过多个绕组实现多路输出的方式,节省了绕组数量,节约了重量、体积和成本,同时还能实现初级开关管的零电压开关(ZVS),降低开关损耗... 详细信息

此处提出了一种双路输出的反激式变换器拓扑,该拓扑只需要一个输出绕组就可以实现双路输出,相比传统的通过多个绕组实现多路输出的方式,节省了绕组数量,节约了重量、体积和成本,同时还能实现初级开关管的零电压开关(ZVS),降低开关损耗。此处首先对所提变换器拓扑实现双路输出和初级开关管ZVS的过程进行模态分析和必要的数学推导,然后对关键参数进行设计,并且对变换器拓扑进行特性分析。最后在Matlab的Simulink中进行仿真验证,并设计制作了一台15 W的样机,验证了所提拓扑的可行性。

关键词：变换器双路输出零电压开关

A case-based method of selecting covariates for digital soil mapping

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Journal of Integrative Agriculture 2020年第8期19卷 2127-2136页

作者： LIANG Peng qin Cheng-zhi ZHU A-xing HOU zhi-wei FAN Nai-qing WANG Yi-jie State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application School of GeographyNanjing Normal UniversityNanjing 210097P.R.China Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023P.R.China Department of Geography University of Wisconsin-MadisonMadisonWI 53706USA

Selecting a proper set of covariates is one of the most important factors that influence the accuracy of digital soil mapping(DSM).The statistical or machine learning methods for selecting DSM covariates are not available for those situations with limited *** solve the problem,this paper proposed a case-based method which could formalize the covariate selection knowledge contained in practical DSM *** proposed method trained Random Forest(RF)classifiers with DSM cases extracted from the practical DSM applications and then used the trained classifiers to determine whether each one potential covariate should be used in a new DSM *** this study,we took topographic covariates as examples of covariates and extracted 191 DSM cases from 56 peer-reviewed journal articles to evaluate the performance of the proposed case-based method by Leave-One-Out cross *** with a novices’commonly-used way of selecting DSM covariates,the proposed case-based method improved more than 30%accuracy according to three quantitative evaluation indices(i.e.,recall,precision,and F1-score).The proposed method could be also applied to selecting the proper set of covariates for other similar geographical modeling domains,such as landslide susceptibility mapping,and species distribution modeling.

关键词： digital soil mapping covariates case-based reasoning Random Forest

Synthesis and cytotoxic activity of novel curcumin analogues

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Chinese Chemical Letters 2008年第3期19卷 281-285页

作者： qin Zhang Yao Fu Hao Wei Wang Tao Gong Yong qin zhi Rong Zhang Key Laboratory of Drug Targeting Drug Delivery Systems Ministry of Education West China School of Pharmacy Sichuan University Chengdu 610041 China

Five novel curcumin analogues bearing different substituents at 4-position of phenyl group were synthesized. Their structures were confirmed by NMR and HRMS spectrum. Their cytotoxic activities against six tumor cell lines were tested by the standard MTT assay in vitro. The results indicated that four analogues （1A-1C, 1E） with solubilizing moieties showed selective potent cytotoxicity against HepG2, HeLa and CT26 cell lines, and analogue 1A and 1C exhibited more potent cytotoxicity than curcumin against CT26 cell line. It was suggested that introduction of appropriate substituents to 4-position of phenyl group might be a potential option for structural modification of curcumin.

关键词： Curcumin analogues Synthesis Cytotoxic activity Anti-tumor activity