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Chemical Constituents of Phacellaria compressa Benth.

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Journal of Integrative Plant Biology 2006年第2期48卷 236-240页

作者： Xiu-Yun Zhang bo-Gang Li min Zhou Xiao-Hong Yuan guo-Lin Zhang Chengdu Institute of Biology the Chinese Academy of Sciences Chengdu 610041 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China College of Life Sciences Northwest Agricultural University Yangling 712100 China

Two new compounds, 1-（3-methoxy-4-hydroxyphenyl）-3-（3,5-dimethoxy-4-hydroxyphenyl）-propane （1） and 5, 7, 3＇-trlmethyoxyflavan-4＇-O-β-D-glucopyranoslde （2） were Isolated from the ethanol extract of the dried aerial parts of Phacellarla compressa Benth., together with 2,3-bis[（4-hydroxy-3,5-dimethoxyphenyl）-methyl]-1,4- butanedlol （3）, ethyl 3,4,5-trlhydroxybenzoate （4）, methyl 3, 4, 5-trlhydroxybenzoete （5）, β-sltoeterol （6）, 5, 7, 3＇, 4＇- tetrahydroxyfiavan （7）, lupeol （8）, zhebelreslnol （9）, quercetln-3-O-α-L-rhamnopyranoslde （10）, （＋）-cetechin （11）, betulln （12）, β-daucosterol （13）, （＋）-sydngareslnol （14）, scopoletln （15）, and proxlmadlol （16）. The structures of these compounds were determined by spectral evidence or by comparing them with authentic samples. Compound 9 showed α-amylase Inhibitory activity of 57.55% at a concentration of 50 μg/mL.

关键词： α-amylase 1,3-diphenyl-propane flavan-4'-O-β-D-glucopyranoside Phacellaria compressa.

Pangolin HKU4-related coronaviruses found in greater bamboo bats from southern China

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Virologica Sinica 2023年第6期38卷 868-876页

作者： min guo Kai Zhao Xingwen Peng Xiangyang He Jin Deng bo Wang Xinglou Yang Libiao Zhang Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationInstitute of ZoologyGuangdong Academy of SciencesGuangzhou510260China Yunnan Key Laboratory of Biodiversity Information Kunming Institute of ZoologyChinese Academy of SciencesKunming650023China Department of Biomedical Sciences and Pathobiology Virginia Polytechnic Institute and State UniversityBlacksburgVA24060USA Hubei Jiangxia Lab Wuhan430071China

Coronavirus(CoV)spillover originating from game animals,particularly pangolins,is currently a significant ***,vigilance is urgently needed for coronaviruses carried by bats,which are known as natural reservoirs of many *** this study,we collected 729 anal swabs of 20 different bat species from nine locations in Yunnan and Guangdong provinces,southern China,in 2016 and 2017,and described the molecular characteristics and genetic diversity of alphacoronaviruses(αCoVs)and betacoronaviruses(βCoVs)found in these *** RT-PCR,we identified 58(8.0%)bat CoVs in nine bat species from six ***,using the Illumina platform,we obtained two representative full-length genomes of the bat CoVs,namely TyRo-CoV-162275 and *** analysis showed that TyRo-CoV-162275 shared the highest identity with Malayan pangolin(Manis javanica)HKU4-related coronaviruses(MjHKU4r-CoVs)from Guangxi Province,whereas TyRo-CoV-162269 was closely related to HKU33-CoV discovered in a greater bamboo bat(Tylonycteris robustula)from Guizhou ***,TyRo-CoV-162275 has a putative furin protease cleavage site in its S protein and is likely to utilize human dipeptidyl peptidase-4(hDPP4)as a cell-entry receptor,similar to MERS*** the best of our knowledge,this is the first report of a bat HKU4r-CoV strain containing a furin protease cleavage *** findings expand our understanding of coronavirus geographic and host distributions.

关键词： Coronavirus Pangolin HKU4r-CoV Bat HKU4r-CoV Tylonycteris robustula Spillover risk

High-temperature oxidation behaviour of minor Hf-dopedβ-NiAI single crystals in dry and humid atmospheres

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Rare Metals 2023年第8期42卷 2767-2773页

作者： Kai Yan Jian He Hong-bo guo School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Oxidation behaviour of undopedβ-NiAl andβ-NiAl-0.05Hf single crystals were investigated at 1100℃in 20 vol%O_(2)+Ar and 15 vol%H2O+Ar,*** contrary to the well-known beneficial effect of Hf additions on the oxidation behaviour of polycrystallineβ-NiAl,severe-scale spallation is observed forβ-NiAl-0.05Hf single-crystal alloy,especially in dry *** is proposed that the presence of the grain boundaries in the polycrystalline substrate enables proper content of Hf segregating at the grain boundaries of the oxide scale and at the scale-substrate interface,which promotes the conditions required for reactive element *** the reactive element effect of Hf does not work,its strong affinity with oxygen will accelerate the process of high-temperature ***,the absence of the grain boundaries as fast diffusion paths partially compromises the adverse influence of water vapour on cyclic oxidation resistance ofβ-NiAl single crystal,resulting in considerable suppression of the oxidation rate and less loss of protection compared with that in dry *** addition,interfacial cavities are observed in dry and humid atmospheres,which may eventually result in the spallation of the oxide scale.

关键词： Oxidation Reactive element Water vapour β-NiAl Grain boundary

Lyapunov-Based Output Containment Control of Heterogeneous Multi-Agent Systems With Markovian Switching Topologies and Distributed Delays

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IEEE/CAA Journal of Automatica Sinica 2023年第6期10卷 1421-1433页

作者： Haihua guo min Meng Gang Feng the Department of Biomedical Engineering City University of Hong KongHong KongChina the Department of Control Science and Engineering College of Electronics and Information Engineeringand Shanghai Research Institute of Intelligent Autonomous SystemsTongji UniversityShanghai 200092China

This paper considers the mean square output containment control problem for heterogeneous multi-agent systems(MASs)with randomly switching topologies and nonuniform distributed *** modeling the switching topologies as a continuous-time Markov process and taking the distributed delays into consideration,a novel distributed containment observer is proposed to estimate the convex hull spanned by the leaders'states.A novel distributed output feedback containment controller is then designed without using the prior knowledge of distributed *** constructing a novel switching Lyapunov functional,the output containment control problem is then solved in the sense of mean square under an easily-verifiable sufficient ***,two numerical examples are given to show the effectiveness of the proposed controller.

关键词： Heterogeneous multi-agent systems Lyapunov method Markovian switching topologies output containment control time delays

Analysis on Genetic Relationship of Oxya chinensis and Oxya japonica from Xuzhou and Pingshan, China

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Agricultural Sciences in China 2006年第2期5卷 116-122页

作者： ZHANG Jian-zhen ZHANG min guo Ya-ping MA En-bo College of Life Science and Technology Shanxi University Taiyuan 030006 P.R.China

Genetic relationship among Oxya chinensis populations and Oxya japonica populations collected from Xuzhou City, Jiangsu Province and Pingshan County, Hebei Province, China were analyzed by random amplified polymorphic DNA （RAPD） markers. A total of 125 DNA bands ranging from 200 to 2 200 bp were amplified by 10 random primers in DNA samples from 43 grasshopper individuals. One hundred and twenty-three （99%） of these bands were polymorphic. Shannon＇s index showed that the genetic, diversity within O. chinensis （0.3432） was higher than that of O. japonica （0.2781）. Nei＇s genetic distance between O. chinensis population and O. japonica population from the same area was less than that between populations from two different areas. The dendrogram based on Nei＇s genetic distance of RAPD markers was constructed using the unweighted pair group method with the arithmetic average （UPGMA） and Neighbor-Joining （NJ） methods. Cluster analysis indicated that all the individuals were grouped into two main clusters. O. chinensis populations from Xuzhou and Pingshan formed one cluster, and O. japonica populations from the two regions belonged to another cluster. The results demonstrated that RAPD can detect within species, and among closely related species. polymorphisms to distinguish minor difference among individuals

关键词： Oxya chinensis Oxya japonica random amplified polymorphic DNA (RAPD) genetic relationship

boosting ferroptosis and microtubule inhibition for antitumor therapy via a carrier-free supermolecule nanoreactor

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Journal of Pharmaceutical Analysis 2023年第1期13卷 99-109页

作者： min Mu Xiaoyan Liang Na Zhao Di Chuan bo Chen Shasha Zhao guoqing Wang Rangrang Fan Bingwen Zou bo Han Gang guo State Key Laboratory of Biotherapy and Cancer Center West China HospitalSichuan UniversityChengdu610041China Key Laboratory of Xinjiang Phytomedicine Resource and Utilization Ministry of EducationSchool of PharmacyShihezi UniversityShiheziXinjiang832002China Department of Neurosurgery West China HospitalSichuan UniversityChengdu610041China Department of Radiation Oncology Cancer CenterWest China HospitalSichuan UniversityChengdu610041China

Traditional microtubule inhibitors fail to significantly enhance+e effect of colorectal cancer;hence,new and efficient strategies are ***+is study,a supramolecular nanoreactor(DOC@TA-Fe^(3+))based on tannic acid(TA),iron ion(Fe^(3+)),and docetaxel(DOC)wi+microtubule inhibition,reactive oxygen species(ROS)generation,and gluta+ione peroxidase 4(GPX4)inhibition,is prepared for ferroptosis/apoptosis *** internalization by CT26 cells,+e DOC@TA-Fe^(3+)nanoreactor escapes from+e lysosomes to release payloads.+e subsequent Fe^(3+)/Fe^(2+)conversion mediated by TA reducibility can trigger+e Fenton reaction to enhance+e ROS ***,Fe^(3+)can consume gluta+ione to repress+e activity of GPX4 to induce ***,+e released DOC controls microtubule dynamics to activate+e apoptosis pa+way.+e superior in vivo antitumor efficacy of DOC@TA-Fe^(3+)nanoreactor in terms of tumor grow+inhibition and improved survival is verified in CT26 tumor-bearing mouse model.+erefore,+e nanoreactor can act as an effective apoptosis and ferroptosis inducer for application in colorectal cancer+erapy.

关键词： Carrier-free nanoreactor Ferroptosis Microtubule Colorectal cancer

Development of 3D printing entity slicing software

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China Foundry 2021年第6期18卷 587-592页

作者： Yang Guan Xun Sun Lei Jin Xin-li guo Zhi-min Zhang guo-yan Shui Lan-bo Ma Shenyang Research Institute of Foundry Co. Ltd.Shenyang 110022China State Key Laboratory of Light Alloy Casting Technology for High-end Equipment Shenyang 110022China

Based on STL(stereo lithography)format file and with Microsoft Visual C^(++)6.0 programming language,a 3D printing slicing software appropriate for the surface strengthening of the parts has been developed,which includes three functions:3D model import,model slicing and data *** the grouping of STL model triangle facets before slicing,the judgment times of the relationship between the triangle facets and the cutting planes are reduced,and the slicing efficiency is *** at the fact that the surface should be strengthened when the part is formed by using of 3D printing process,the function of identifying and marking the surface of the geometric entity is accomplished in the slicing software,which can strengthen the surface of the part according to the user’s *** developed slicing software can provide an entity slicing file for 3D printing *** related functions can be adjusted and improved according to user’s needs,which makes the software convenient and flexible to use.

关键词： STL format 3D printing slicing surface strengthening

Equilibrium between titanium ions and high-purity titanium electrorefining in a NaCl-KCl melt

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International Journal of minerals,Metallurgy and Materials 2014年第7期21卷 660-665页

作者： Jian-xun Song Qiu-yu Wang guo-jing Hu Xiao-bo Zhu Shu-qiang Jiao Hong-min Zhu State Key Lab of Advanced Metallurgy University of Science and Technology Beijing

TiClx （x=2.17） was prepared by using titanium sponge to reduce the concentration of TiCl4 in a NaCl-KCl melt under negative pressure. The as-prepared NaCl-KCl-TiClx melt was employed as the electrolyte, and two parallel crude titanium plates and one high-purity titanium plate were used as the anode and cathode, respectively. A series of electrochemical tests were performed to investigate the influence of electrolytic parameters on the current efficiency and quality of cathodic products. The results indicated that the quality of cathodic products was related to the current efficiency, which is significantly dependent on the current density and the initial concentration of titanium ions. The significance of this study is the attainment of high-purity titanium with a low oxygen content of 30× 10^-6.

关键词： titanium electrodeposition ionic equilibrium high purity materials oxygen concentration

The Quasi-reversibility Method to Solve the Cauchy Problems for Parabolic Equations

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Acta Mathematica Sinica,English Series 2013年第8期29卷 1617-1628页

作者： Jing LI bo Ling guo School of Mathematics and Computational Science Changsha University of Science and Technology Institute of Applied Physics and Computational Mathematics

In this paper, on the one hand, we take the conventional quasi-reversibility method to obtain the error estimates of approximate solutions of the Cauchy problems for parabolic equations in a sub-domain of QT with strong restrictions to the measured boundary data. On the other hand, weakening the conditions on the measured data, then combining the duality method in optimization with the quasi-reversibility method, we solve the Cauchy problems for parabolic equations in the presence of noisy data. Using this method, we can get the proper regularization parameter ε that we need in the quasi-reversibility method and obtain the convergence rate of approximate solutions as the noise of amplitude δ tends to zero.

关键词： Ⅲ-posed problems parabolic equations Cauchy problems quasi-reversibility