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Journal of Oceanology and Limnology 2021年第5期39卷 1730-1739页

作者： Lin GONG Swee-cheng LIM mei YANG Xinzheng LI Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China National University of Singapore Tropical Marine Science InstituteSingapore 119227Singapore

A new species of Macandrewia Gray from a seamount near Yap Trench in the Western Pacific Ocean was *** yapensis *** distinct from its congeners by possessing a foliate shape with contorted lamellae,tuberculiform terminations of desmas,and unique size of *** is the third species of Macandrewia described from the Pacific *** addition a partial sequence of COI gene was obtained from the new specimen and then it submitted to *** tree constructed with the partial COI sequences appears to exhibit a more congruent relationship with morphological data of macandrewiid species compared to 28 S gene tree.

关键词： ’Lithistid’demosponges morphological and molecular analyses new species Macandrewia yapensis sp.nov

Synthesis and characterization of two-dimensional lead-free(K, Na)NbO3 micro/nano piezoelectric structures

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Journal of Advanced Ceramics 2020年第1期9卷 27-34页

作者： Li-Qian cheng mei FENG Yiwen SUN Zhen ZHOU Ze XU State Key Laboratory of Coal Resources and Safe Mining Department of Materials Science and EngineeringChina University of Mining&Technology(Beijing)Beijing 100083China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Two-dimensional(2 D)lead-free(K,Na)Nb O3(KNN)micro/nano structures with controllable K/Na ratio were successfully fabricated via a two-step molten salt synthesis(MSS).In this work,the reaction factors,including the proportion of molten salts,the types of carbonates,the sintering temperature,and the sintering time,were discussed in detail and the optimized condition was *** microstructure of KNN was confirmed by confocal Raman spectroscopy,while piezoresponse force microscopy(PFM)was applied to measure three-dimensional(3 D)morphology and piezoelectric properties of KNN *** as-synthesized KNN platelets apparently possess anisotropic morphology and uniform structure,the size of which reaches 5–20μm in length/width and 0.5–1μm in *** should be noted that the K/Na ratios of the KNN crystals are basically consistent while the proportion of salts changes within a certain *** enrichment of Na element in the products is also observed,which owes to the smaller ionic radius of Na+comparing to that of K+.This result provides a reference for the further preparation of textured ceramics and flexible piezoelectric generators.

关键词： (K,Na)NbO3(KNN) lead-free two-dimensional(2D)structure piezoelectric property

Cosmic-Ray Positrons Produced by Pulsar Winds from Mature Gamma-Ray Pulsars

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Chinese Physics Letters 2001年第5期18卷 701-704页

作者： ZHANG Li K.S.cheng mei Dong-cheng Department of Physics Yunnan UniversityKunming 650091 Department of Physics University of Hong KongPokfulam RoadHongKong Yunnan Observatory Chinese Academy of SciencesKunming 650011

In the frame of theγ-ray pulsar outer gap model,e^(±)pairs in the pulsar magnetosphere are produced by the cascade of e^(±)pairs through synchrotron radiation of the return current from the outer *** pairs are accelerated mono-energetically to relativistic energies in the pulsar wind driven by low-frequency electromagnetic *** Monte Carlo simulations,we generate a sample of the matureγ-ray pulsars in our Galaxy and calculate the positron production rate from these *** a simple leaky box model,we calculate the ratio of cosmic-ray positron to total *** result indicates that the pulsar contribution to the cosmic ray positron peaks at about 40 GeV and the observed e^(+)/(e^(-)+e^(+))ratio can be explained by this model.

关键词： cosmic outer return

Design,synthesis and biological evaluation of amino organophosphorus imidazoles as a new type of potential antimicrobial agents

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Science China Chemistry 2017年第6期60卷 769-785页

作者： Wei-Wei Gao Syed Rasheed VijaiKumarReddy Tangadanchu Yi Sun Xin-mei Peng Yu cheng Feng-Xiu Zhang Jian-mei Lin cheng-He Zhou Institute of Bioorganic&Medicinal Chemistry Key Laboratory of Applied Chemistry of Chongqing MunicipalitySchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China School of Medicine University of Electronic Science and Technology of China Chengdu 610072China

A series of amino organophosphorus imidazoles were designed and synthesized as a novel structural type of antimicrobial *** evaluation in vitro showed that compound 3f exhibited equipotent or superior anti-methicillin-resistant Staphylococcus aureus(anti-MRSA) and anti-S. cerevisiae efficiencies(minimal inhibitory concentration(MIC)=2 μg/mL) to clinical drugs,and the combinations with antibacterial or antifungal drugs enhanced the antimicrobial efficiency. Highly active molecule 3f showed low propensity for bacteria to develop resistance, and the preliminary action mechanism studies demonstrated that 3f was membrane-active, but had no significant intercalation towards MRSA DNA. The computational study on 3f reasonably explained its high antimicrobial activity. Experimental data revealed that ground-state 3f-HSA complexes were formed mainly through hydrophobic interactions and hydrogen bonds with a spontaneous process, and the non-radioactive energy transfer from HSA to 3f occurred beyond F鰎ster resonance energy transfer theory. The participation of metal ions in 3f-HSA supramolucular system could increase the concentration of free compound 3f, and shorten its storage time and half-life in the blood to improve the maximum antimicrobial efficacy.

关键词： organophosphorus imidazole antibacterial antifungal HSA

Effect of die structure parameters on deformation behavior of bent tube in free bending process

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Journal of Iron and Steel Research International 2023年第3期30卷 487-503页

作者： Wei Wang cheng cheng Li Wan Jie Tao Xun-zhong Guo Chun-mei Liu College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211100JiangsuChina State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074HubeiChina Capital Aerospace Machinery Corporation Beijing 100076China

The bending section of tube between the bending die and the guider is in a less constrained state during the free bending *** free bending dies have the important impact on the plastic deformation behavior and the forming quality of *** study the evolution law of the deformation behavior of tube with the die structure parameters and optimize the free bending die parameters,the free bending experiments and the corresponding numerical simulations were carried *** design principle of free bending die was *** free bending experiment was conducted to verify the reliability of the numerical simulation *** on the numerical simulation results,the influence of the distance between the center point of bending die and the front end of guider on the forming quality of bent tube is more obvious than that of the fillet of ***,the fillet of bending die hardly affects the stress and strain distribution and the evolution of the wall ***,the free bending experiments with the newly determined free bending dies were *** ultimate bending radius of bent tube is reduced and the forming quality is improved.

关键词： Free bending Die structure parameter Forming quality Numerical simulation Tube

On the Light Curve and Spectra of X-Rays and Gamma-Rays from the Crab Pulsar

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Chinese Physics Letters 2000年第7期17卷 544-546页

作者： ZHANG Li K.S.cheng mei Dong-cheng Yunnan Astrophysics Center Yunnan UniversityKunming 650091 Department of Physics University of Hong KongPokfulam RoadHong Kong

We use a three-dimensional pulsar magnetosphere model to study the light curve and spectra of x-rays and gamma-rays from the Crab pulsar. In this model, the vertical size of the outer gap is first determined by a self-consistent model in which the outer gap is limited by pair production from collisions of thermal photons produced by polar cap heating of backflow outer gap current and curvature photons emitted by gap accelerated charged particles. The transverse size of the outer gap is determined by local pair production conditions. In principle, there are two topologically disconnected outer gaps present in the magnetosphere of a pulsar, and both incoming and outgoing particle flows are allowed. However, double-peak light curves with strong bridges are most common, Making use of the three-dimensional structure of the outer gap and its local properties, we compare the results of our model with the light curve and phase-resolved spectra of the Crab pulsar.

关键词： particles conditions outer

Pure Multiplicative Noises Induced Population Extinction in an Anti-tumor Model under Immune Surveillance

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Communications in Theoretical Physics 2009年第9期52卷 463-467页

作者： WANG Can-Jun LI Di mei Dong-cheng Nonlinear Research Institute Baoji University of Arts and Sciences Baoji 721007 China Department of Physics Yunnan University Kunming 650091 China

The dynamical characters of a theoretical anti-tumor model under immune surveillance subjected to a pure multiplicative noise are investigated. The effects of pure multiplicative noise on the stationary probability distribution （SPD） and the mean first passage time （MFPT） are analysed based on the approximate Fokker-Planck equation of the system in detail. For the anti-tumor model, with the multiplieative noise intensity D increasing, the tumor population move towards to extinction and the extinction rate can be enhanced. Numerical simulations are carried out to check the approximate theoretical results. Reasonably good agreement is obtained.

关键词： multiplicative noise anti-tumor model

Endoscopic polypectomy: A promising therapeutic choice for esophageal carcinosarcoma

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World Journal of Gastroenterology 2009年第27期15卷 3448-3450页

作者： Feng Ji Yue-mei Xu cheng-Fu Xu Department of Gastroenterology the First Affiliated Hospital College of Medicine Zhejiang University Hangzhou 310003 Zhejiang Province China

Esophageal carcinosarcoma is a rare malignant tumor composing of both carcinomatous and sarcomatous elements. Endoscopic therapy is less invasive and may represent an alternative to esophagectomy for superf icial esophageal carcinosarcoma. Here, we report a 61-year-old male who was diagnosed as esophageal carcinosarcoma and underwent endoscopic polypectomy with well tolerance and favorable prognosis. We also present a brief review of the literature.

关键词： Carcinosarcoma Endoscopic polypectomy Endoscopic ultrasonography

Interleukin-6 polymorphisms modify the risk of periodontitis: a systematic review and meta-analysis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第12期10卷 920-927页

作者： mei-ying SHAO Ping HUANG Ran cheng Tao HU State Key Laboratory of Oral Diseases Sichuan University Chengdu 610041 China

Objective： To clarify the association ofIL-6 polymorphisms and periodontitis, a meta-analysis of case-control studies and a systemic review were conducted. Material and methods： We performed a literature search using PubMed and Medline database to May 2009, with no restrictions. We also reviewed references from all retrieved articles. Six case-control studies involving 1093 periodontitis cases and 574 controls were selected for meta-analysis to assess the purported associations between IL-6 polymorphisms and the risk of periodontitis. IL-6 -174 G/C and -572 C/G polymorphisms were included in the present meta-analysis, and the association between IL-6 -6331 TIC polymorphism and the risk of periodontitis was adequately reviewed as well. Results and conclusion： The present meta-analysis indicates that the IL-6 -174 G allele could not modify the risk of chronic periodontitis, but increased the risk of aggressive periodontitis. And -572 C/G polymorphism is associated with the pathogenesis of periodontitis, including chronic periodontitis or aggressive periodontitis.

关键词： Interleukin-6 Polymorphism Periodontitis Risk Meta-analysis

Recent tree growth decline unprecedented over the last four centuries in a Tibetan juniper forest

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Journal of Forestry Research 2019年第4期30卷 1429-1436页

作者： Yu-mei Mou Ouya Fang Xuehan cheng Hongyan Qiu State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences20 NanxincunXiangshanBeijing 100093People's Republic of China University of Chinese Academy of Sciences 19(A)Yuquan RoadShijingshan DistrictBeijing 100049People's Republic of China

Forest structure and function are subject to risks of growth declines from intensified drought and frequent extreme events related to climate *** of tree growth declines will help anticipate future responses of forests to climate *** this study,we investigated tree growth declines over the last four centuries in a juniper forest on the eastern Tibetan *** analyzing the radial growth trajectories of individual trees,we identified two events of intense growth decline,one in 1817–1830 and the other in 1969–1999 over the past four *** intensity of the recent decline was unprecedented in the period under ***-width chronology showed a positive correlation with self-calibrating Palmer Drought Severity Indices and a negative correlation with mean monthly temperatures in May and *** recent intensified growth decline may have been due to temperatureinduced frequent droughts in the study *** findings suggest that trees in this juniper forest may face a higher risk of growth decline and even mortality under continued climate warming.

关键词： Climate change Dendroecology Drought Forest health Growth decline