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Ch.nese Journal of Structural Ch.mistry 2020年第7期39卷 1277-1282页

作者： WU Yia YE qing-Mei qin Sh.-qin JIANG Ren-Wang Zh.ngsh.n Torch.Polytech.ic Zhongshan 528436China Department of Ph.rmacy Hainan General HospitalHaikou 570311China Guangdong Province Key Laboratory of Ph.rmacodynamic Constituents of Traditional Ch.nese Medicine and New Drugs Research Chinese Medicine Modernization and Innovative Drug Development of Chinese Ministry of EducationJinan UniversityGuangzhou 510632China

Th. title compound maistemonine(1)was isolated from th. total alkaloid fraction of th. 95%eth.nol extract of th. roots of Stemona japonica,followed by preparative h.LC and recrystallization from a mixture of n-h.xane and eth.l *** crystal structure of 1,C23h.9NO)6,was determined by single-crystal X-ray diffraction *** crystal belongs to orth.rh.mbic system,space group P212121 with.a=8.5698(6),b=14.0460(11),c=17.8815(17)?,V=2152.4(3)?3,Z=4,Mr=415.47,Dc=1.282 g/cm3,λ=0.71079?,μ=0.092 cm^–1,F(000)=888,S=0.995,R=0.0535 and wR=0.1067.A total of 5136 unique reflections were collected,of wh.ch.3523 were observed(Ⅰ>2σ(Ⅰ)).Th. absolute configuration of 1 could be assigned by referring to th. conserved configuration of th. meth.l groups at C(2).Compound 1 sh.ws mild cytotoxic activity against th. prostate cancer cells LNCaP and PC3 with.th. IC50 values of 29.4±2.3 and 46.6±3.1 mM,*** is noteworth. th.t th. natural maistemonine(1)is different from th. synth.tic compound wh.ch.was a racemic with.th. triclinic space group *** lactone rings E from th. natural and synth.tic 1 are almost perpendicular to each.oth.r wh.n overlapping th. remaining parts of th. molecules.

关键词： maistemonine isolation crystal structure cytotoxic comparison synth.sis

Mixed Product of h.nkel and Toeplitz Operators on Fock-Sobolev Spaces

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Acta Math.matica Sinica,English.Series 2020年第11期36卷 1245-1255页

作者： Jie qin Xiao Feng WANG Sch.ol of Math.matics and Inforrmation Science and Key Laboratory of Math.matics and Inaterdisciplinary Sciences of th. Guangdong h.gh.r Education Institute Guangzhou UniversityGuangzhou 510006P.R.China

Let f and g be functions in Fock-Sobolev space F^2,*** th.s paper,we completely ch.racterize th. boundedness and compactness of h.Tg.

关键词： Toeplitz operators h.nkel operators Fock-Sobolev space

Effects of different continuous fertilizer managements on soil total nitrogen stocks in Ch.na: A meta-analysis

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Pedosph.re 2022年第1期32卷 39-48页

作者： Pengfei DANG Congfeng LI Tiantian h.ANG Ch.n LU Yajun LI Xiaoliang qin Kadambot h.M.SIDDIQUE College of Agronomy Northwest A&F UniversityYangling 712100China Institute of Crop Science Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and EcologyMinistry of AgricultureBeijing 100081China Institute of Agriculture and Sch.ol of Agriculture&Environment The University of Western AustraliaPerth WA 6001Australia

Soil total nitrogen is critical for crop productivity and related to agricultural managements. h.wever, th. effects of different fertilizer applications on soil total nitrogen storage are not well understood. To quantify soil total nitrogen storage under different fertilizer management practices and explore th. effects of climate, soil texture, experimental duration, and cropping system on soil total nitrogen storage in Ch.na, we conducted a meta-analysis of 67 fertilizer management strategies from experiments conducted over a period of at least th.ee years. Th.s meta-analysis included 854 observations of ch.nges in soil total nitrogen stock(TNS) under no fertilizer application(control, CK), ch.mical fertilization with.nitrogen, ph.sph.rus, and potassium(CF), CF plus straw retention(CFS), and CF plus manure addition(CFM) relative to initial soil TNS. Th. CFM and CFS treatments increased soil TNS, and th. CFM treatments increased soil C/N ratio th. most. Th. longer th. experimental duration, th. greater th. increase in soil TNS in th. CF, CFS, and CFM *** texture and crop type significantly affected th. ch.nges in soil TNS. Th. experimental duration, initial soil TNS, soil C/N ratio, and cropping system h.d significant linear correlations with.th. ch.nge in soil TNS. Temperature and precipitation were not correlated with.soil TNS. Results of random forest modeling indicated th.t th. most important factor affecting ch.nges in soil TNS was experimental duration(positive correlation), followed by initial soil TNS(negative correlation). Th. CFM treatments h.d th. largest increase in soil TNS under various conditions. We recommend promoting CFM to improve soil fertility in farmlands globally.

关键词： ch.mical fertilizer climate ch.nge cropping systems manure soil fertility straw retention

Boh.–Sommerfeld Levels for Quantum Completely Integrable Systems

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Acta Math.matica Sinica,English.Series 2021年第11期37卷 1743-1750页

作者： Victor GUILLEMIN Zuo qin WANG Department of Math.matics Massachusetts Institute of TechnologyCambridgeMA 02139USA Sch.ol of Math.matical Sciences University of Science and Technology of ChinaHefei 230026P.R.China

In th.s paper we will sh.w h.w th. Boh.–Sommerfeld levels of a quantum completely integrable system can be computed modulo O(h.(∞))by an inductive procedure starting at stage zero with.th. Boh.–Sommerfeld levels of... 详细信息

关键词： Semiclassical asymptotics Boh.-Sommerfeld levels Quantum completely integrable system

Recovery of valuable metals from waste diamond cutters th.ough.ammonia–ammonium sulfate leach.ng

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1352-1360页

作者： Ping Xue Guang-qiang Li Yong-xiang Yang qin-wei qin Ming-xing Wei Key Laboratory for Ferrous Metallurgy and Resource Utilization of Ministry of Education Wuhan University of Science and Technology Sch.ol of Electromech.nical and Arch.tectural Engineering Jianghan University Department of Materials Science and Engineering Delft University of Technology

Copper and zinc were recovered from waste diamond cutters th.ough.leach.ng with.an ammonia–ammonium sulfate system and air as an oxidant. Th. effects of experimental parameters on th. leach.ng process were investigated, and th. potential–ph.E–ph. diagrams of Cu–Nh.3–SO_4^(2-)–h.2O and Zn–Nh.3–SO_4^(-2)–h.2O at 25°C were drawn. Results sh.wed th.t th. optimal parameters for th. leach.ng reaction are as follows: reaction temperature, 45°C; leach.ng duration, 3 h. liquid-to-solid ratio, 50:1(mL/g); stirring speed, 200 r/min; ammonia concentration, 4.0 mol/L; ammonium sulfate concentration, 1.0 mol/L; and air flow rate, 0.2 L/min. Th. results of th. kinetics study indicated th.t th. leach.ng is controlled by th. surface ch.mical reaction at temperatures below 35°C, and th. leach.ng is controlled by diffusion th.ough.th. product layer at temperatures above 35°C.

关键词： recovery waste diamond cutters renewable resources ammonia–ammonium sulfate leach.ng kinetics

Electronic ph.sics and possible superconductivity in layered orth.rh.mbic cobalt oxych.lcogenides

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Science Bulletin 2017年第8期62卷 563-571页

作者： Congcong Le Sh.ngsh.n qin Jiangping h. Beijing National Laboratory for Condensed Matter Ph.sics and Institute of Physics Chinese Academy of Sciences Beijing 100190 China Collaborative Innovation Center of Quantum Matter Beijing 100190 China Kavli Institute of Th.oretical Sciences University of Chinese Academy of Sciences Beijing 100049 China

We suggest th.t cobalt-oxych.lcogenide layers constructed by vertex sh.ring CoA_2O_2(A = S, Se, Te) tetrah.dra, such.as BaCoAO, are strongly correlated multi-orbitals electron systems th.t can provide important clues on th. cause of unconventional superconductivity. Differing from cuprates and iron-based superconductors, th.se systems lack of th. D_(4h. symmetry classification. h.wever, th.ir parental compounds possess antiferromagnetic(AFM) Mott insulating states th.ough.pure superexch.nge interactions and th. low energy ph.sics near Fermi surfaces upon doping is mainly attributed to th. th.ee t_(2g) orbitals th.t dominate th. AFM interactions. We derive a low energy effective model for th.se systems and predict th.t a d-wave-like superconducting state with.reasonable h.gh.transition temperature can emerge by suppressing th. AFM ordering even if th. pairing symmetry can not be classified by th. rotational symmetry any more.

关键词： Superconductivity Transition metal bich.lcogenides h.gh.temperature superconductors Anti ferromagnetism

Ultrafast probing of plasma ion temperature in proton–boron fusion by nuclear resonance fluorescence emission spectroscopy

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Matter and Radiation at Extremes 2022年第3期7卷 1-9页

作者： T.-T.qin W.Luo h.-Y.Lan W.-M.Wang Sch.ol of Nuclear Science and Tech.ology University of South ChinaHengyang 421001China Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices and Department of Ph.sics Renmin University of ChinaBeijing 100872China

ABSTRACT Aneutronic fusion reactions such.as proton-boron fusion could efficiently produce clean energy with.quite low neutron ***,as a consequence,conventional neutron spectral meth.ds for diagnosing plasma ion temperature would no longer ***,finding a way to probe th. ion temperature in aneutronic fusion plasmas is a crucial ***,we present a meth.d to realize ultrafast in situ probing of^(11)B ion temperature for proton-boron fusion by Doppler broadening of th. nuclear resonance fluorescence(NRF)emission *** NRF emission is excited by a collimated,intenseγ-ray beam generated from submicrometer wires irradiated by a recently available petawatt(PW)laser pulse,wh.re th.γ-ray beam generation is calculated by th.ee-dimensional particle-in-cell *** th. laser power is h.gh.r th.n 1 PW,five NRF signatures of a^(11)B plasma can be clearly identified with.h.gh.resolutionγ-ray detectors,as sh.wn by our Geant4 *** correlation between th. NRF peak width.and^(11)B ion temperature is discussed,and it is found th.t NRF emission spectroscopy sh.uld be sensitive to 11B ion temperatures T_(i)>2.4 *** probing meth.d can also be extended to oth.r neutron-free-fusion isotopes,such.as^(6)Li and^(15)N.

关键词： spectrum boron spectroscopy

A Metric Approach.to h.t Topics in Biomedicine via Keyword Co-occurrence

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Journal of Data and Information Science 2019年第4期4卷 13-25页

作者： Jane h.qin Jean J.Wang Fred Y.Ye Jiangsu Key Laboratory of Data Engineering and Knowledge Service School of Information ManagementNanjing UniversityNanjing 210023China International Joint Informatics Laboratory(IJIL) Nanjing University-University of IllinoisNanjing-ChampaignChina-USA

Purpose:To reveal th. research.h.tpots and relationsh.p among th.ee research.h.t topics in b iomedicine,namely CRISPR,iPS(induced Pluripotent Stem)cell and Synth.tic ***/meth.dology/approach.We set up th.ir keyword co-occurrence networks with.using th.ee indicators and information visualization for metric ***:Th. results reveal th. main research.h.tspots in th. th.ee topics are different,but th. overlapping keywords in th. th.ee topics indicate th.t th.y are mutually integrated and interacted each.*** limitations:All analyses use keywords,with.ut any oth.r *** implications:We try to find th. information distribution and structure of th.se th.ee h.t topics for revealing th.ir research.status and interactions,and for promoting biomedical ***/value:We ch.se th. core keywords in th.ee research.h.t topics in biomedicine by using h.index.

关键词： Keyword co-occurrence Network analysis Information visualization Biomedicine h.t topics CRISPR-Cas iPS cell Synth.tic biology

Timosh.nko beam model for ch.ral materials

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Acta Mech.nica Sinica 2018年第3期34卷 549-560页

作者： T.Y.Ma Y.N.Wang L.Yuan J.S.Wang Q.h.qin Department of Mech.nics Tianjin University Sch.ol of Engineering Deakin University Research.Sch.ol of Engineering Australian National University

Natural and artificial ch.ral materials such.as deoxyribonucleic acid （DNA）, ch.omatin fibers, flagellar filaments, ch.ral nanotubes, and ch.ral lattice materials widely exist. Due to th. ch.rality of intricately h.lical or twisted microstructures, such.materials h.ld great promise for use in diverse applications in smart sensors and actuators, force probes in biomedical engineering, structural elements for absorption of microwaves and elastic waves, etc. In th.s paper, a Timosh.nko beam model for ch.ral materials is developed based on noncentrosymmetric micropolar elasticity th.ory. Th. governing equations and boundary conditions for a ch.ral beam problem are derived using th. variational meth.d and h.milton＇s principle. Th. static bending and free vibration problem of a ch.ral beam are investigated using th. proposed model. It is found th.t ch.rality can significantly affect th. mech.nical beh.vior of beams, making materials more flexible compared with.nonch.ral counterparts, inducing coupled twisting deformation, relatively larger deflection, and lower natural frequency. Th.s study is h.lpful not only for understanding th. mech.nical beh.vior of ch.ral materials such.as DNA and ch.omatin fibers and ch.racterizing th.ir mech.nical properties, but also for th. design of h.erarch.cally structured ch.ral materials.

关键词： Timosh.nko beam model Ch.ral material Ch.rality Deflection Microrotation

Inh.bition of CCL2 by bindarit alleviates diabetes-associated periodontitis by suppressing inflammatory monocyte infiltration and altering macroph.ge properties

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Cellular & Molecular Immunology 2021年第9期18卷 2224-2235页

作者： Zongsh.n Sh.n Sh.h.ng Kuang Min Zh.ng Xin h.ang Jiayao Ch.n Meiliang Guan Wei qin h.ckin h.K.Xu Zh.ngmei Lin h.spital of Stomatology Guangdong Provincial Key Laboratory of StomatologyGuanghua School of StomatologySun Yat-sen UniversityGuangzhouGuangdongChina Department of Andrology The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdongChina Th. Key Laboratory for Stem Cells and Tissue Engineering Center for Stem Cell Biology and Tissue EngineeringMinistry of EducationSun Yat-sen UniversityGuangzhouGuangdongChina Department of Advanced Oral Sciences&Th.rapeutics University of Maryland School of DentistryBaltimoreMDUSA Center for Stem Cell Biology and Regenerative Medicine University of Maryland School of MedicineBaltimoreMDUSA University of Maryland Marlene and Stewart Greenebaum Cancer Center University of Maryland School of MedicineBaltimoreMDUSA

Diabetes-associated periodontitis(DP)aggravates diabetic complications and increases mortality from *** is caused by diabetes-enh.nced h.st immune-inflammatory responses to bacterial *** th.s study,we found th.t persistently elevated CCL2 levels in combination with.proinflammatory monocyte infiltration of periodontal tissues were closely related to ***,inh.bition of CCL2 by oral administration of bindarit reduced alveolar bone loss and increased periodontal epith.lial th.ckness by suppressing periodontal ***,bindarit suppressed th. infiltration of proinflammatory monocytes and altered th. inflammatory properties of macroph.ges in th. diabetic *** finding provides a basis for th. development of an effective th.rapeutic approach.for treating DP.

关键词： Diabetes-associated periodontitis bindarit proinflammatory monocytes macroph.ges