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当归多糖调控肠道菌群对脑缺血再灌注小鼠的影响

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中国临床解剖学杂志 2024年第3期42卷 270-277页

作者：阙松年涂经典韩尚峰熊航宋海旺黄涛贵州医科大学基础医学院人体解剖学教研室贵阳561113

目的探讨当归多糖(Angelica Sinensis Polysaccharide,ASP)改善小鼠肠道微生态对脑缺血再灌注(Ischemia/reperfusion injury,I/R injury)的影响。方法将雄性SPF级昆明小鼠随机分为假手术组(Sham组),大脑中动脉栓塞组(MCAO组),当归多糖灌胃组(ASP组),粪菌移植组(Fecal microbiota transplantation,ASP-FMT),每组16只。连续给药7 d后建立MCAO模型,24 h后使用mNSS法检测小鼠神经功能缺陷评分;TTC染色法检测脑梗死相对面积;试剂盒法测定右侧大脑缺血半暗带组织SOD、MDA、GSH含量;Western blot测定炎症因子IL-1β、IL-5、IL-6、IL-10表达量;盲肠内容物16s rRNA测序分析肠道微生物多样性。结果与MCAO组相比,ASP干预后小鼠神经功能明显改善(P<0.001),脑梗死相对面积明显减少(P<0.01),氧化应激水平下降(P<0.05);与MCAO组相比,ASP降低了脑组织IL-1β、IL-5及IL-6表达、上调IL-10表达量(P<0.05);MACO后小鼠肠道菌群丰富度明显减少,益生菌比例下调,当归多糖灌胃或菌群移植均可部分恢复菌群丰富度,上调益生菌比例;肠道菌群的变化与脑组织损伤程度具有相关性。结论当归多糖通过改善肠道微生态,降低氧化应激水平,下调炎症因子水平,减轻脑缺血再灌注后神经功能损伤,减少梗死范围。

关键词：脑缺血再灌注损伤当归多糖肠道菌群炎症反应

Electron beam welding of Re and BT5-1 titanium alloy

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Rare Metals 2005年第3期24卷 293-297页

作者： YANG Shanglei XUE Xiaohuai LOU songnian CHEN Yan LI Shimin Institute of Welding Shanghai Jiaotong University Shanghai 200030 China

Based on the binary alloy phase diagram of Re-Ti, the weldability of Re and BT5-1 titanium alloy was analyzed. Using two methods of direct electron beam welding （EBW-D） and intergradafion electron beam welding （EBW-I）, Re and BT5-1 was welded. Experimental results show that the joint figuration of EBW-D between Re and BT5-1 is not fine, and the joint is inclined to brittleness rupture. The joint figuration of EBW-I between Re and BT5-1 is fine. No cracking and other disfigures occur in the intergradation joint. The element distribution of Re, Me, and Ti in the weld metal is progressional diversification.

关键词： welding intergradation layer electron beam rhenim titanim alloy

Rice Genomics: over the Past Two Decades and into the Future

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Genomics, Proteomics & Bioinformatics 2018年第6期16卷 397-404页

作者： Shuhui Song Dongmei Tian Zhang Zhang songnian Hu Jun Yu BIG Data Center Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Domestic rice(Oryza sativa L.) is one of the most important cereal crops, feeding a large number of worldwide populations. Along with various high-throughput genome sequencing projects, rice genomics has been making great headway toward direct ?eld applications of basic research advances in understanding the molecular mechanisms of agronomical traits and utilizing diverse germplasm resources. Here, we brie?y review its achievements over the past two decades and present the potential for its bright future.

关键词： Rice genome Genomic diversity Heterosis Domestication

Analytics of big geosocial media and crowdsourced data

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Big Earth Data 2021年第1期5卷 1-4页

作者： songnian Li Monica Wachowicz Hongchao Fan Ryerson University TorontoCanada University of New Brunswick FrederictonCanada Norwegian University of Science and Technology TrondheimNorway

Numerous crowdsourcing and social media platforms such as CrowdSpring,Idea Bounty,DesignCrowd,Facebook,Twitter,Flickr,Weibo,WeChat,and Instagram are creating and sharing vast amounts of user-generated content that can reveal timely and useful infor-mation for detecting traffic patterns,mitigating security risks and other types of time-critical events,discovering social structures characteristics,predicting human movement,***,also known as volunteered geographic information(VGI),has added a new dimension to traditional geospatial data acquisition by providing fine-grained proxy data for human activity research in urban studies(Chen et al.,2016;Niu&Silva,2020).However,analyzing big geosocial media and crowdsourced data brings significant methodological and theoretical challenges due to the uncertain user representability when referring to human behavior in general,the inherent noisy data that requires high-performance cost of preprocessing,and the heterogeneity in quality and quantity of *** particular,geosocial media data and their derived metrics can provide valuable insights and policy strategies,but they require a deep understanding of what the metrics actually measure(Zook,2017).All of these underpin complex assessments,not mention-ing the ethnic and privacy ***,new sets of methods and tools are required to analyze the big data from crowdsourcing and social media platforms.

关键词： source media covering

Disaggregating population data for assessing progress of SDGs:methods and applications

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International Journal of Digital Earth 2022年第1期15卷 2-29页

作者： Yue Qiu Xuesheng Zhao Deqin Fan songnian Li Yijing Zhao College of Geoscience and Surveying Engineering China University of Mining and Technology (Beijing)BeijingPeople’s Republic of China Department of Civil Engineering Ryerson UniversityTorontoCanada

Rapid population growth has had a significant impact on society,economy and environment,which will challenge the achievement of the United Nations Sustainable Development Goals(SDGs).Spatially accurate and detailed population distribution data are essential for measuring the impact of population growth and tracking progress on the ***,most population data are evenly distributed within administrative units,which seriously lacks spatial *** are scale differences between the population statistical data and geospatial data,which makes data analysis and needed research *** disaggregation method is an effective way to obtain the spatial distribution of population with greater *** can also transform the statistical population data from irregular administrative units into regular grids to characterize the spatial distribution of the population,and the original population count is *** paper summarizes the research advances of population disaggregation in terms of methodology,ancillary data,and products and discusses the role of spatial disaggregation of population statistical data in monitoring and evaluating SDG ***,future work is proposed from two perspectives:challenges with spatial disaggregation and disaggregated population as an Essential SDG Variable(ESDGV).

关键词： Population disaggregation dasymetric mapping SDG indicators assessment

A Brief Review on the Mechanisms of miRNA Regulation

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Genomics, Proteomics & Bioinformatics 2009年第4期7卷 147-154页

作者： Yimei Cai Xiaomin Yu songnian Hu Jun Yu Key Laboratory of Genome Sciences and Information Beijing Institute of Genomics Chinese Academy of Sciences Beijing 100029 China.

MicroRNAs （miRNAs） are a class of short, endogenously-initiated non-coding RNAs that post-transcriptionally control gene expression via either translational repression or mRNA degradation. It is becoming evident that miRNAs are playing significant roles in regulatory mechanisms operating in various organisms, including developmental timing and host-pathogen interactions as well as cell differentiation, proliferation, apoptosis and tumorigenesis. Likewise, as a regulatory element, miRNA itself is coordinatively modulated by multifarious effectors when carrying out basic functions, such as SNP, miRNA editing, methylation and circadian clock. This mini-review summarized the current understanding of interactions between miRNAs and their targets, including recent advancements in deciphering the regulatory mechanisms that control the biogenesis and functionality of miRNAs in various cellular processes.

关键词： non-coding RNA miRNA miRNA regulation targets

ALGORITHM AND IMPLEMENTATION OF AUTO-SEARCHING WELD LINE FOR WELDING MOBILE ROBOT

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 176-180页

作者： ZHANG Ke Lü Xueqin　 WU Yixiong L0U songnian Institute of Welding Engineering Shanghai Jiaotong UniversityShanghai 200030 China

An algorithm of auto-searching weld line for welding mobile robot is presented. Auto-searching weld line is that the robot can automatically recognize a weld groove according to the characteristics of the weld groove before welding, and then adjust itself posture to the desired status preparing for welding, namely, it is a process that the robot autonomously aligns itself to the center of welding seam. Firstly, the configuration of welding mobile robot with the function of auto-searching weld line is introduced, then the algorithm and implementation of auto-searching weld line are presented on the basis of kinematics model of the robot, at last trajectory planning among auto-searching weld line is investigated in detail. The experiment result shows that the developed welding mobile robot can successfully implement the task of auto-searching weld line before welding, tracking error precision can be controlled to approximate ±1.5 mm, and satisfy the requirement of practical welding project.

关键词： Welding mobile robot Auto-searching weld line Trajectory planning

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基于放大器优化的无中继通信系统研究

光通信研究 2024年第4期 13-19页

作者：吴俊宇敖学渊邓磊戴潇潇付松年刘陈杨奇华中科技大学光电信息学院武汉430074 深圳华中科技大学研究院深圳518000 广东工业大学信息工程学院广州510006 广东省信息光子技术重点实验室广州510006

【目的】传统无中继通信系统中需要使用分布式拉曼泵浦放大器和遥泵放大器,而分布式拉曼泵浦放大器和遥泵放大器均需要使用高功率泵浦激光源,并且会提高无中继通信系统光学链路复杂度。针对这一问题,文章提出了使用高功率掺铒光纤放大器... 详细信息

【目的】传统无中继通信系统中需要使用分布式拉曼泵浦放大器和遥泵放大器,而分布式拉曼泵浦放大器和遥泵放大器均需要使用高功率泵浦激光源,并且会提高无中继通信系统光学链路复杂度。针对这一问题,文章提出了使用高功率掺铒光纤放大器(EDFA)取代无中继通信系统中的前向分布式拉曼泵浦放大器的无中继通信系统架构。【方法】文章通过VPI仿真平台建模分析比较了所提无中继通信系统架构的传输性能并进行了实时无中继通信传输实验验证。【结果】仿真结果表明,使用高功率泵浦提高信号光入纤功率能够实现传统无中继通信系统中的前向拉曼泵浦放大增益效果,并且更适合配合波分复用(WDM)技术实现更高速率的无中继通信传输。通过实验还证实了采用仅使用EDFA泵浦放大结构的无中继通信系统能够实现500 km跨度距离10 Gbit/s速率下的单通道无中继通信传输,并且在结合WDM技术的情况下,能够实现4×10 Gbit/s速率、500 km光纤链路跨度下的通信传输。【结论】文章所提仅采用EDFA泵浦放大的无中继通信传输系统架构能够极大地简化传统无中继通信系统架构,且能够基于EDFA泵浦放大布置多通道WDM系统从而提升系统通信传输的信号速率,对未来无中继通信系统结构简化以及通信速率提升具有重要的实际意义。

关键词：无中继通信实时通信 VPI仿真光纤光学掺铒光纤放大器

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Analytical geospatial Digital Earth

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International Journal of Digital Earth 2014年第4期7卷 253-255页

作者： Bert Veenendaal songnian Li Suzana Dragicevic Maria Antonia Brovelli Curtin University PerthWAAustralia Ryerson University TorontoONCanada Simon Fraser University BurnabyBCCanada Politecnico di Milano ComoItaly

Digital Earth is a virtual representation of the planet,encompassing all its systems and forms,including human societies,manifested as a multidimensional,multiscale,multi-temporal,and multilayer information facility(Goodchild et al.2012).The Digital Earth vision envelops the vast array of technologies,information frameworks,organizational standards,along with applications across a spectrum of disciplines,and many educational and grassroots operational needs(Guo 2008).

关键词： Earth planet Analytical