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Coffee drinking and pancreatic cancer risk:A meta-analysis of cohort studies

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World Journal of Gastroenterology 2011年第9期17卷 1204-1210页

作者： Jie Dong Jian zou Xiao-Feng yu Department of Gastroenterology Huadong Hospital Fudan University Shanghai200040 China

AIM:To quantitatively assess the relationship between coffee consumption and incidence of pancreatic cancer in a meta-analysis of cohort studies. METHODS:We searched MEDLINE,EMBASE,Science Citation Index Expanded and bibliographies of retrieved *** were included if they reported relative risks(RRs)and corresponding 95%CIs of pancreatic cancer with respect to frequency of coffee *** performed random-effects meta-analyses and metaregressions of study-specific incremental estimates to determine the risk of pancreatic cancer associated with a 1 cup/d increment in coffee consumption. RESULTS:Fourteen studies met the inclusion criteria, which included 671 080 individuals(1496 cancer events) with an average follow-up of 14.9 *** with individuals who did not drink or seldom drank coffee per day,the pooled RR of pancreatic cancer was 0.82 (95%CI:0.69-0.95)for regular coffee drinkers,0.86 (0.76-0.96)for low to moderate coffee drinkers,and 0.68(0.51-0.84)for high *** subgroup analyses,we noted that,coffee drinking was associated witha reduced risk of pancreatic cancer in men,while this association was not seen in *** associations were also similar in studies from North America,Europe, and the Asia-Pacific region. CONCLUSION:Findings from this meta-analysis suggest that there is an inverse relationship between coffee drinking and risk of pancreatic cancer.

关键词： Coffee Cohort study Meta-analysis Pancreatic neoplasm

Dielectronic Recombination on He+ with Non-isolated Resonance Approach

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Chinese Physics Letters 2000年第2期17卷 96-98页

作者： zou yu ZHAO LI-Bo FANG quan-yu Institute of Applied Physics and Computational Mathematics Beijing 100088 Department of Applied Physics Beijing University of Aeronautics and AstronauticsBeijing 100083

Based on the relativistic multichannel theory, a non-isolated resonance approach has been developed to calculate the cross sections of dielectronic recombination on He+ for △n=1 and 2 transitions. A first order approximation is adopted for the radiative process. The convolved cross sections for the n≤3 states in both transitions are in good agreement with those of the observations. It is shown that the l-dependence of the field ionization and the radiative decay during the time-of-flight affect significantly the measurement of the cross sections near the initial state of the field ionization.

关键词： process transitions radiative

EBSD Characterization of the Laser Remelted Surface Layers in a Commercially Pure Mg

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Journal of Materials Science & Technology 2014年第3期30卷 263-267页

作者： Kemin Zhang Jianxin zou Jun Li Zhishui yu School of Materials Engineering Shanghai University of Engineering Science National Engineering Research Center of Light Alloys Net Forming & School of Materials Science and Engineering Shanghai Jiao Tong University

Laser surface melting has been applied on a commercially pure Mg. The microstructure and texture modifications encountered in the surface layers were carefully investigated by using electron backscattered diffraction （EBSD） technique. Due to the melting followed by rapid solidification and cooling, a layer having graded microstructures and texture formed. At the bottom of the melted layer, the solidified Mg grains have an elongated shape with a 〈0001 〉 basal fibre texture nearly parallel to sample normal direction, while equiaxed grains were observed in the top melted layer having a much weaker basal fibre texture. Solidification twinning and deformation twinning were found in the vicinity of the melt/substrate interface where the Mg grains grow larger due to the heating. In addition, no epitaxial type grain growth was observed at the melt/substrate interface.

关键词： Pure Mg Laser surface melting Solidification Texture

Statistical analysis of intensity variations in tropical cyclones in the East China Sea passing over the Kuroshio

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Journal of Oceanology and Limnology 2020年第6期38卷 1632-1639页

作者： yu Yang DONG Changming SHAN Haixia zou Bin College of Marine Sciences Nanjing University of Information Science&TechnologyNanjing 210044China National Satellite Ocean Application Service Ministry of Natural ResourcesBeijing 100080China Southern Laboratory of Ocean Science and Engineering Zhuhai 519000China

Intensity variations of the SE-NW-oriented tropical cyclones(TC)in the East China Sea(ECS)passing over the Kuroshio are studied using multi-year high-resolution sea surface temperature data,the tropical cyclone data,and the global reanalysis *** statistical results show that there are 81 TCs passing over the Kuroshio from the southeast in the East China Sea,over 68 years from 1949 to *** terms of the change of the atmospheric pressure in the center of the TC,there are three categories:31 TCs are intensified,28 maintain their intensities,and 22 *** seasonal differences are presented in the *** the analysis on the intensified TCs,it is found that the TCs in the range where the center translational speed is from 1 m/s to 8 m/s and the distance from the Kuroshio main axis is from 10 km to 75 km are intensified more *** analysis of three specific examples of TCs show that the stronger characteristics of the Kuroshio warm water in the ECS,the greater the intensity increase of such tropical cyclones.

关键词： intensity of typhoons Kuroshio East China Sea

Relativistic Multichannel Theory:Scaling Behavior of Multichannel Quantum Defect Theory Parameters(μ_(α),U_(iα)) Along the Ne-Like Iso-electronic Sequence

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Chinese Physics Letters 1996年第4期13卷 269-272页

作者： zou yu TONG Xiao-min LI Jia-ming Institute of Physics Chinese Academy of SciencesBeijing 100080 Institute of Applied Physics and Computational Mathematics Beijing 100088

The compact physical parameters(μ_(α),U_(iα))in multichannel quantum defect theory(MQDT)can be directly calculated with relativistic multichannel theory(RMCT).Here we report a systematic study of the MQDT parameters(fiay Uia)with RMCT along the Ne-like iso-electronic sequence(including Ca^(10+),Fe^(16+),Ge^(22+),Ag^(37+) ions).We find that the physical parameters(μ_(α),U_(iα))show a very interesting scaling behavior along the iso-electronic sequence.

关键词： electronic MQDT scaling

Event vertex and time reconstruction in large-volume liquid scintillator detectors

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Nuclear Science and Techniques 2021年第5期32卷 51-62页

作者： Zi-yuan Li yu-Mei Zhang Guo-Fu Cao Zi-Yan Deng Gui-Hong Huang Wei-Dong Li Tao Lin Liang-Jian Wen Miao yu Jia-heng zou Wu-Ming Luo Zheng-yun You School of Physics Sun Yat-Sen UniversityGuangzhou 510275China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics and Technology Wuhan UniversityWuhan 430072China

Large-volume liquid scintillator detectors with ultra-low background levels have been widely used to study neutrino physics and search for dark *** vertex and event time are not only useful for event selection but also essential for the reconstruction of event *** this study,four event vertex and event time reconstruction algorithms using charge and time information collected by photomultiplier tubes were analyzed *** effects of photomultiplier tube properties were also *** results indicate that the transit time spread is the main effect degrading the vertex reconstruction,while the effect of dark noise is *** addition,when the event is close to the detector boundary,the charge information provides better performance for vertex reconstruction than the time information.

关键词： JUNO Liquid scintillator detector Neutrino experiment Vertex reconstruction Time reconstruction

Roles and relevance of mast cells in infection and vaccination

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The Journal of Biomedical Research 2016年第4期30卷 253-263页

作者： yu Fang zou Xiang Department of Microbiology and Immunology Clinical Research CenterAffiliated Hospital of Guizhou Medical UniversityGuiyangGuizhou 550025China Department of Microbiology and Immunology Mucosal Immunobiology and Vaccine Research CenterInstitute of BiomedicineUniversity of GothenburgGothenburg 40530Sweden

In addition to their well-established role in allergy mast cells have been described as contributing to functional regulation of both innate and adaptive immune responses in host defense. Mast cells are of hematopoietic origin but typically complete their differentiation in tissues where they express immune regulatory functions by releasing diverse mediators and cytokines. Mast cells are abundant at mucosal tissues which are portals of entry for common infectious agents in addition to allergens. Here, we review the current understanding of the participation of mast cells in defense against infection. We also discuss possibilities of exploiting mast cell activation to provide adequate adjuvant activity that is needed in high-quality vaccination against infectious diseases.

关键词： mast cell infection host defense vaccine adjuvant

Synthesis, UV-curing Behavior and Surface Properties of New Fluorine-containing Aromatic Oxetane Monomers

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Chinese Journal of Polymer Science 2018年第4期36卷 521-527页

作者： Shu-Qing Fang yu-Lian Pang Ying-Quan zou College of Chemistry Beijing Normal University

In this paper, we combined high-end cationic UV-curable material with fluorinated chain obtaining a series of new fluorine-containing aromatic oxetane monomers via a mild nucleophilic substitution reaction. The structures and properties of monomers were characterized using ~1 H-NMR, ^（19） F-NMR, dynamic viscosity tests and differential scanning calorimetry（DSC）. It was determined that all of the fluorinated monomers obtained had much lower viscosity and higher thermostability after the introduction of hexafluorobenzene. Then, UV-curable coatings were prepared using four fluorine-containing aromatic oxetane monomers（FOX1-4）; the UV-curing kinetics, with three kinds of initiators, and properties of the cured films were evaluated using real-time Fourier transform infrared（FTIR） spectroscopy, water and diiodomethane contact angle tests, surface energy calculations and scanning electron microscopy（SEM）. The FTIR spectroscopy results showed that the coatings possessed excellent conversion rate（〉 99% with liquid initiator PAG-201 in 150 s）, and as the fluorine content increased, the monomers exhibited decreased mobility with the increasing viscosity and worse solubility with fluorinated monomers, resulting in a lower conversion rate. Moreover, the coatings possessed favorable hydrophobic and oleophobic properties and low surface energies owing to the fluoride chains floating to the membrane-air interface, which was also confirmed by discrete concave structures in SEM images. These new kinds of monomers can replace traditional fluorinated cationic monomers applied to the fingerprint resistant, fouling resistant, scratch resistant and anti-aging coatings, adhesives or printing ink materials.

关键词： Fluorine-containing monomers Oxetane UV-curing kinetics Surface properties

Optimized Consensus for Blockchain in Internet of Things Networks via Reinforcement Learning

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Tsinghua Science and Technology 2023年第6期28卷 1009-1022页

作者： Yifei zou Zongjing Jin Yanwei Zheng Dongxiao yu Tian Lan Institute of Intelligent Computing School of Computer Science and TechnologyShandong UniversityQingdao 266237China Department of Electrical and Computer Engineering George Washington UniversityWashingtonDC 20052USA

Most blockchain systems currently adopt resource-consuming protocols to achieve consensus between miners;for example,the Proof-of-Work(PoW)and Practical Byzantine Fault Tolerant(PBFT)schemes,which have a high consumption of computing/communication resources and usually require reliable communications with bounded ***,these protocols may be unsuitable for Internet of Things(IoT)networks because the IoT devices are usually lightweight,battery-operated,and deployed in an unreliable wireless ***,this paper studies an efficient consensus protocol for blockchain in IoT networks via reinforcement ***,the consensus protocol in this work is designed on the basis of the Proof-of-Communication(PoC)scheme directly in a single-hop wireless network with unreliable communications.A distributed MultiAgent Reinforcement Learning(MARL)algorithm is proposed to improve the efficiency and fairness of consensus for miners in the blockchain *** this algorithm,each agent uses a matrix to depict the efficiency and fairness of the recent consensus and tunes its actions and rewards carefully in an actor-critic framework to seek effective *** results from the simulation show that the fairness of consensus in the proposed algorithm is guaranteed,and the efficiency nearly reaches a centralized optimal solution.

关键词： consensus in blockchain Proof-of-Communication(PoC) MultiAgent Reinforcement Learning(MARL) Internet of Things(IoT)networks