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The determinant of performance of cross-border M&As in China: A comparative study between overseas Sino and Anglo firms 被引量:1
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作者 Ki Hyun Ryu Jae Eun Lee 《Chinese Business Review》 2009年第12期44-52,共9页
This study examines the factors that affect the performance of foreign acquiring firms in Chinese M&As (mergers and acquisitions) market. Comparing between overseas Sino-Group and Anglo-Group, this study found that... This study examines the factors that affect the performance of foreign acquiring firms in Chinese M&As (mergers and acquisitions) market. Comparing between overseas Sino-Group and Anglo-Group, this study found that familiarity and location were the most important factors influencing performance of M&A transactions in China. It also found that unrelated M&A deals should be merged with familiarity for gaining positive acquisition performance. The total sample used in this study was 3,442 cases from October 1980 to March 2005. Because this period included all deals of M&As after the opening of Chinese market in China. The authors' finding provided a more universal explanation in the cross-border M&As in China. 展开更多
关键词 cross-border m&as acquisition performance FAmILIARITY LOCATION
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Research on decision-making behavior of multi-agent alliance in cross-border electricity market environment: an evolutionary game
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作者 Zhao Luo Chenming Dong +3 位作者 Xinrui Dai Hua Wang Guihong Bi Xin Shen 《Global Energy Interconnection》 EI CSCD 2024年第6期707-722,共16页
Constructing a cross-border power energy system with multiagent power energy as an alliance is important for studying cross-border power-trading markets.This study considers multiple neighboring countries in the form ... Constructing a cross-border power energy system with multiagent power energy as an alliance is important for studying cross-border power-trading markets.This study considers multiple neighboring countries in the form of alliances,introduces neighboring countries’exchange rates into the cross-border multi-agent power-trading market and proposes a method to study each agent’s dynamic decision-making behavior based on evolutionary game theory.To this end,this study uses three national agents as examples,constructs a tripartite evolutionary game model,and analyzes the evolution process of the decision-making behavior of each agent member state under the initial willingness value,cost of payment,and additional revenue of the alliance.This research helps realize cross-border energy operations so that the transaction agent can achieve greater trade profits and provides a theoretical basis for cooperation and stability between multiple agents. 展开更多
关键词 multi-agent alliance cross-border transactions Electricity market Evolutionary game DECISION-mAKING
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Impact of BRICS Trade Facilitation on China's Exports Using Cross-Border E-Commerce
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作者 Longling LI Kaimei CHEN Zijian LONG 《Asian Agricultural Research》 2024年第5期1-7,共7页
With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important forc... With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important force in the global economy, and the progress of the BRICS countries' trade facilitation level has an important impact on the global trade environment. This paper conducts an in-depth study of the dynamic changes in BRICS trade facilitation from 2013 to 2022, and uses an extended gravity model to analyze the specific impact of this change on China's exports using cross-border e-commerce. The results show that although the BRICS countries have made some progress in trade facilitation, the overall level still needs to be improved, and there are obvious differences among member countries. However, the improvement of trade facilitation among BRICS countries has undoubtedly brought significant positive effects to China's exports using cross-border e-commerce. 展开更多
关键词 Trade facilitation BRICS cross-border e-commerce Export trade
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Iran-Turkmenistan Relations:Cross-Border Ethnic Groups and Comprehensive Governance Strategies
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作者 WU Tongyu 《International Relations and Diplomacy》 2024年第5期181-190,共10页
This study delves into the bilateral relations between Iran and Turkmenistan,focusing on the multidimensional impacts of cross-border ethnic groups,cultural diplomacy,and energy cooperation.The research reveals that d... This study delves into the bilateral relations between Iran and Turkmenistan,focusing on the multidimensional impacts of cross-border ethnic groups,cultural diplomacy,and energy cooperation.The research reveals that despite challenges in security cooperation,such as regional political ideological differences and uneven power distribution,Iran has adopted diverse strategies to enhance cultural identity,social cohesion,and promote economic cooperation.Iran actively seeks to repair relations with Turkmenistan by emphasizing shared historical and cultural backgrounds,particularly the presence of cross-border Turkmen ethnic groups.Specific measures include developing cultural tourism,organizing cultural weeks,and establishing commemorative days.In the economic sphere,the two countries have signed significant natural gas supply agreements,strengthening energy cooperation.Iranian leaders often emphasize“blood ties”and deep cultural connections in diplomatic statements,combining cultural diplomacy with practical economic cooperation.The study’s findings indicate that Iran’s initiatives have led to the reorganization of national space and social reconstruction in border regions,promoting changes in public policy.By integrating cultural identity,historical connections,and economic interests,Iran has adopted a sophisticated diplomatic approach,laying the foundation for more stable and enduring bilateral relations while contributing to regional stability and sustainable development. 展开更多
关键词 Iranian foreign policy cross-border ethnic groups Iran-Turkmenistan relations
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Micro,Small,and Medium Enterprises’Cross-Border Business Strategies
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作者 Xuan Chen Yijun Xia Tian Hou 《Proceedings of Business and Economic Studies》 2024年第2期191-197,共7页
This paper explores the operational strategies of cross-border micro, small, and medium enterprises (MSMEs). Against the backdrop of globalization and digitalization, cross-border trade has become one of the important... This paper explores the operational strategies of cross-border micro, small, and medium enterprises (MSMEs). Against the backdrop of globalization and digitalization, cross-border trade has become one of the important pathways for many MSMEs to achieve growth and competitive advantage. Firstly, the paper outlines the concept and characteristics of cross-border MSMEs, as well as the analysis of their operational environment in the context of globalization, including political, economic, social, technological, environmental, and legal factors. Secondly, the paper proposes operational strategies for cross-border MSMEs, including international market selection and positioning, cross-border marketing strategies, supply chain management, cross-border financial management, and cross-border risk management. Finally, the paper summarizes the importance of effectively implementing these strategies for cross-border MSMEs to seize international market opportunities, reduce operational risks, and enhance competitiveness and profitability. 展开更多
关键词 cross-border mSmEs Operational strategies GLOBALIZATION DIGITALIZATION International market cross-border trade marketing finance and risk management Supply chain management
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Research on Cross-border E-commerce Empowering the Transformation and Upgrading of Dongguan’s Manufacturing Industry
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作者 Shoufei Su Juan Zhang 《Proceedings of Business and Economic Studies》 2024年第6期207-212,共6页
With the rise of the global digital economy and the deep integration of digital technology into traditional manufacturing operations,cross-border e-commerce provides a new commercial model and pathways for transformin... With the rise of the global digital economy and the deep integration of digital technology into traditional manufacturing operations,cross-border e-commerce provides a new commercial model and pathways for transforming and upgrading Dongguan’s traditional manufacturing industry.It also offers perspectives for enhancing the integration of online and offline operations while advancing the industrial Internet process.This study examines the impact of cross-border e-commerce on Dongguan manufacturing,highlighting its role in improving production efficiency,expanding international markets,and driving industrial upgrading through product enhancement,supply chain optimization,and innovative business models.By incorporating practical cases and data analysis from Dongguan enterprises,this study investigates the benefits and challenges of cross-border e-commerce in the transformation of the manufacturing industry,aiming to offer a reference for enterprise digital transformation and global competitive strategies. 展开更多
关键词 cross-border e-commerce Dongguan manufacturing Transformation and upgrading Case study
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2023-08-23辽宁普兰店M 4.6地震震源参数测定及发震构造初判
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作者 戴盈磊 张文静 +2 位作者 杨晓东 索锐 王承伟 《大地测量与地球动力学》 北大核心 2025年第1期48-54,59,共8页
2023-08-2318:19辽宁省大连市普兰店区发生M 4.6地震,为准确描述本次地震的震源特征,探讨其孕育和发震机理,本文通过测定地震的震源深度,反演震源机制、矩张量及质心深度,给出震源机制中心解;同时分析震源机制与构造应力场的关系,根据... 2023-08-2318:19辽宁省大连市普兰店区发生M 4.6地震,为准确描述本次地震的震源特征,探讨其孕育和发震机理,本文通过测定地震的震源深度,反演震源机制、矩张量及质心深度,给出震源机制中心解;同时分析震源机制与构造应力场的关系,根据小震重定位结果对发震断层面进行拟合,初步确定了本次地震的发震断层。结果表明,普兰店M 4.6地震初始破裂深度为12.0 km,震源机制解参数为节面Ⅰ走向50°,倾伏角75°,滑动角-169°;节面Ⅱ走向317°,倾伏角80°,滑动角-15°,矩震级M W4.8,最优质心深度12 km;地震矩M_(0)为1.796×10^(16)Nm,矩张量解M_(rr)、M_(tt)、M_(pp)、M_(rt)、M_(rp)、M_(tp)分别为-0.004、0.946、-0.942、0.017、-0.305、-0.125;中心解参数为节面Ⅰ走向47.03°,倾伏角79.04°,滑动角-168.15°;节面Ⅱ走向314.75°,倾伏角78.37°,滑动角-11.19°。构造应力场作用在中心解节面Ⅰ上的相对剪应力为0.877,相对正应力为-0.544;投影于节面Ⅱ上的相对剪应力为0.911,相对正应力为0.161。拟合的断层面走向148.91°,倾伏角89.85°,其在构造应力体系下的滑动角为26.47°。综合分析认为,普兰店M 4.6地震发生在NW向普兰店-长海构造带,是沿应力场最优节面以左旋走滑为错动方式的天然地震。 展开更多
关键词 普兰店m 4.6地震 初至P震相定位法 gCAP 震源机制 构造应力场
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血浆m1A及其编码器基因对结肠腺癌诊断的综合分析
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作者 朱立强 孙金旗 +6 位作者 冀恒涛 吴亚丽 韩晶晶 彭仁佳 樊清波 马卫国 李庆华 《胃肠病学和肝病学杂志》 2025年第1期25-30,共6页
目的探讨m1A RNA甲基化相关基因和血浆m1A甲基化水平对结肠腺癌(colorectal adenocarcinoma,COAD)的诊断效能,为COAD早期诊断提供新的方案。方法通过UALCAN、The Human Protein Atlas和TCGA-GTEx数据库,分析COAD组织和正常结肠组织中m1... 目的探讨m1A RNA甲基化相关基因和血浆m1A甲基化水平对结肠腺癌(colorectal adenocarcinoma,COAD)的诊断效能,为COAD早期诊断提供新的方案。方法通过UALCAN、The Human Protein Atlas和TCGA-GTEx数据库,分析COAD组织和正常结肠组织中m1A相关基因mRNA和蛋白水平的差异表达。利用ELISA法检测收集于我院初诊的COAD患者和正常人血浆中m1A甲基化水平。结合COAD临床病理特征分析m1A甲基化对COAD的诊断效能。结果m1A编码器和读码器基因的蛋白水平和mRNA水平在COAD组织中的表达显著上调,其中以TRMT6和TRMT10C两个编码器表达升高最为显著。两个编码器基因均可作为COAD诊断,尤其是早期诊断标志物,且其AUC均达到0.9以上。m1A总体甲基化水平在COAD血浆中明显升高,并可作为早期COAD的诊断标志物。结论m1A编码器基因和血浆m1A在COAD中明显升高,有望成为一种新的早期COAD诊断标志物。 展开更多
关键词 结肠腺癌 m1A 诊断 血浆
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高糖环境通过抑制免疫反应基因1的表达诱导巨噬细胞促炎性 M1型极化
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作者 罗维 王宇航 +2 位作者 刘延松 王媛媛 艾磊 《南方医科大学学报》 北大核心 2025年第1期1-9,共9页
目的研究高糖环境对巨噬细胞极化的影响及其潜在分子机制。方法将离体培养的RAW264.7细胞随机分为过表达对照组(NC-OE组)、免疫反应基因1过表达组(IRG1 OE组)、沉默对照组(NC-siRNA组)和IRG1沉默组(IRG1 siRNA组),电穿孔进行质粒转染后... 目的研究高糖环境对巨噬细胞极化的影响及其潜在分子机制。方法将离体培养的RAW264.7细胞随机分为过表达对照组(NC-OE组)、免疫反应基因1过表达组(IRG1 OE组)、沉默对照组(NC-siRNA组)和IRG1沉默组(IRG1 siRNA组),电穿孔进行质粒转染后再组内随机分为对照组(Con组)和高糖组(HG组),60 mmol/L葡萄糖干预72 h后收集细胞进行检测。CCK-8检测细胞活性,相差显微镜观察细胞形态,Western blotting检测细胞中IRG1、iNOS、Arg-1、IL-1β和IL-10蛋白表达,免疫荧光染色检测细胞中iNOS和Arg-1蛋白荧光水平,ELISA法检测细胞培养基中IL-1β和IL-10蛋白水平。结果与对应Con组相比,HG组IRG1表达均下降(P<0.01),同时出现较多梭形和多突形细胞且两极可见伸展的伪足,iNOS表达升高(P<0.01)、Arg-1表达下降(P<0.05),IL-1β表达和分泌升高(P<0.05)、IL-10分泌下降(P<0.01)。转染IRG1过表达质粒后,与对应NC-OE组相比,IRG1 OE组IRG1水平均升高(P<0.01);高糖环境下,HG-IRG1 OE组梭形和多突形细胞明显减少、iNOS表达下降(P<0.01)、Arg-1表达升高(P<0.01)、IL-1β表达和分泌下降(P<0.01)、IL-10表达和分泌升高(P<0.05)。IRG1沉默后,与对应NC-siRNA组相比,IRG1 siRNA组IRG1水平降低(P<0.01);高糖环境下,HG-IRG1 siRNA组多突形细胞和伪足进一步增加、Arg-1表达降低(P<0.01)、IL-10表达和分泌减少(P<0.05)。结论高糖环境诱导巨噬细胞促炎性M1型极化进而诱发慢性炎症反应,其作用机制可能与抑制巨噬细胞中IRG1蛋白表达有关。 展开更多
关键词 巨噬细胞 m1型极化 炎症因子 高糖环境 免疫反应基因1
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“一用即弃社会”的可持续性议题:对M市二手物品分享和再利用的实地研究
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作者 张敦福 《广东社会科学》 北大核心 2025年第1期203-214,共12页
作为可持续生产与可持续消费的重要环节,二手物品的分享和循环再利用是一个十分重要的议题。该议题因中国的垃圾分类和生态文明建设备受关注。对西方某城市(M市)的实地研究表明:慈善团体和民间机构在二手物品的分享和循环再利用中均比... 作为可持续生产与可持续消费的重要环节,二手物品的分享和循环再利用是一个十分重要的议题。该议题因中国的垃圾分类和生态文明建设备受关注。对西方某城市(M市)的实地研究表明:慈善团体和民间机构在二手物品的分享和循环再利用中均比较活跃;在政府垃圾管理体制中,幸运的需求者在垃圾投放日可拣拾可用的二手物品;居民和租户通过车库大甩卖或庭院甩卖,低价出售或免费赠送不再需要的服装鞋帽、家具、日用品、修理工具、影像制品、书籍等等;互助与公益导向的各类用品回收再利用的互联网平台不仅惠及M市居民,而且覆盖全球主要城市。总之,不同的机构、活动与制度安排结合在一起,构成了一个稳定、持久、可靠的二手物品分享、循环、再利用的网络,在可持续消费中发挥重要作用。 展开更多
关键词 “一用即弃的社会” 可持续消费 二手物品 m 分享 循环再利用
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SF3B1/FOXM1/JUNB轴调控SOX21表达对宫颈癌细胞生物学行为的影响研究
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作者 高洁 阿依努尔·色义提 +2 位作者 谢丽 夏依拉·艾合买提 侯友翔 《成都医学院学报》 2025年第1期1-5,10,共6页
目的分析剪接因子3B亚基1/叉头框转录因子M1/转录因子活化蛋白激酶B(SF3B1/FOXM1/JUNB)轴调控转录因子21抗体(SOX21)表达对宫颈癌细胞生物学行为的影响。方法选取2022年3月至2023年12月新疆医科大学附属肿瘤医院收治的50例宫颈癌患者的... 目的分析剪接因子3B亚基1/叉头框转录因子M1/转录因子活化蛋白激酶B(SF3B1/FOXM1/JUNB)轴调控转录因子21抗体(SOX21)表达对宫颈癌细胞生物学行为的影响。方法选取2022年3月至2023年12月新疆医科大学附属肿瘤医院收治的50例宫颈癌患者的癌旁组织及癌组织作为研究对象,利用实时荧光定量PCR检测SF3B1、FOXM1、JUNB、SOX21表达;通过Transwell、细胞计数试剂8(CCK8)检测宫颈癌细胞生物学行为(增殖、迁移、侵袭);利用蛋白质印迹法测定SF3B1、FOXM1、JUNB、SOX21蛋白表达。结果与癌旁组织相比,宫颈癌组织JUNB表达低,FOXM1、SOX21、SF3B1表达高,差异有统计学意义(P<0.05);与si-NC组相比,si-SF3B1/FOXM1/JUNB组0 h OD450值高,侵袭细胞数、迁移细胞数、(24、48 h)OD450值、SF3B1、FOXM1、JUNB低,差异有统计学意义(P<0.05);与OE-NC组相比,OE-SOX21组迁移细胞数、(0、24、48 h)OD450值、SOX21、侵袭细胞数高,差异有统计学意义(P<0.05);与si-SF3B1/FOXM1/JUNB+OE-NC组相比,si-SF3B1/FOXM1/JUNB+OE-SOX21组SOX21、SF3B1、FOXM1、JUNB、(0、24、48 h)OD450值、侵袭细胞数、迁移细胞数高,差异有统计学意义(P<0.05)。结论SF3B1/FOXM1/JUNB轴通过激活SOX21表达可促进宫颈癌细胞侵袭、增殖、迁移。 展开更多
关键词 剪接因子3B亚基1/叉头框转录因子m1/转录因子活化蛋白激酶B 转录因子21抗体 宫颈癌细胞 迁移 侵袭 增殖
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Business English Talent Cultivation Research under the Background of Cross-border E-commerce 被引量:1
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作者 刘聪 《海外英语》 2018年第18期246-247,共2页
The meteoric rise of cross-border e-commerce has become one of the pillars of our foreign trade, while the lack of quali-fied talents in the industry may restrict its benign development. This paper analyzes the major ... The meteoric rise of cross-border e-commerce has become one of the pillars of our foreign trade, while the lack of quali-fied talents in the industry may restrict its benign development. This paper analyzes the major problems existing in the BusinessEnglish talents cultivation in university, and offers advice for the construction of training modal for Business English talents basedon the cross-border e-commerce. 展开更多
关键词 Business English TALENT CULTIVATION cross-border E-COmmERCE
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Problems in Cross-border E-commerce Export Trade in China & Countermeasure Analysis 被引量:3
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作者 Yang Zhenhua Shen Qiang 《International Journal of Technology Management》 2015年第10期63-66,共4页
As an emerging industry in China, cross-border e-commerce has enjoyed the leap-forward development, along with increasingly prominent problems. This paper aims at finding out the problems and related roots that hinder... As an emerging industry in China, cross-border e-commerce has enjoyed the leap-forward development, along with increasingly prominent problems. This paper aims at finding out the problems and related roots that hinder its development, through conducting an analysis on the export development of cross-border e-commerce, in order to look for solutions and countermeasures in favor of its sound development and to promote the liberalization development of foreign trade in China. 展开更多
关键词 cross-border E-commerce Export cross-border Logistics cross-border E-commerce Supervision
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5 m低净空工况基坑支护开挖施工与实测研究
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作者 黎兴望 詹炎培 +2 位作者 杨平 魏领先 张婷 《建筑技术》 2025年第1期74-79,共6页
以苏州市轨道交通某地铁车站基坑为例,阐述了5m低净空工况下采取钻孔灌注桩+MJS工法桩施作基坑围护结构与低净空基坑分区开挖的施工工艺。通过实测分析围护结构变形、邻近高架桥墩台沉降、地表沉降变化、支撑轴力变化、水位变化的发展... 以苏州市轨道交通某地铁车站基坑为例,阐述了5m低净空工况下采取钻孔灌注桩+MJS工法桩施作基坑围护结构与低净空基坑分区开挖的施工工艺。通过实测分析围护结构变形、邻近高架桥墩台沉降、地表沉降变化、支撑轴力变化、水位变化的发展规律。结果表明:盖板下基坑部分自开始开挖至坑底,钻孔灌注桩最大侧向位移值呈增大趋势,最大侧向位移点位置深度随开挖深度逐渐下移至开挖深度的1.1倍处。随着基坑开挖位置逐渐远离桥墩台,墩台竖向位移变化量逐渐减小,同时基坑背面一侧地表沉降未出现较大变化,显而易见,桥桩桩身周围的隔离桩有效隔离了坑外地表沉降,支撑轴力变化随基坑开挖深度增加显现即时性特点。此外,基坑东北角潜水位一直低于预警值,但未见明显渗漏情况。证明5 m低净空工况下基坑采取地下连续墙结合钻孔灌注桩围护结构及MJS止水帷幕的施工方案具有合理性。 展开更多
关键词 5 m净空 基坑开挖 沉降 水位变化
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Index system and methods for comprehensive assessment of cross-border power grid interconnection projects 被引量:1
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作者 Teng Zhao Yizhe Jiang +4 位作者 Han Jiang Yi Gao Wei Wu Chen Wang Jinxiang Zhu 《Global Energy Interconnection》 CAS 2020年第6期532-544,共13页
With the global economy integration and progress in energy transformation,it has become a general trend to surpass national boundaries to achieve wider and optimal energy resource allocations.Consequently,there is a c... With the global economy integration and progress in energy transformation,it has become a general trend to surpass national boundaries to achieve wider and optimal energy resource allocations.Consequently,there is a critical n eed to adopt scie ntific approaches in assessi ng cross-border power grid interconnection projects.First,con sidering the promotion of large-scale renewable energy resources and improvements in system adequacy,a comprehensive assessment index system,including costs,socio-economic benefits,environmental benefits,and technical benefits,is established in this study.Second,a synthetic assessment framework is proposed for cross-border power grid interconnection projects based on the index system comprising cost-benefit analysis,with market and network simulations,iterative methods for indicator weight evaluation,and technique for order preferenee by similarity to an ideal solution(TOPSIS)method for the project rankings.Fin ally,by assessi ng and comparing three cross-border projects betwee n Europe and Asia,the proposed index system and assessment framework have been proved to be effective and feasible;the results of this system can thus support investment decision-making related to such projects in the future. 展开更多
关键词 cross-border power grid interconnection Comprehensive assessment index system Cost-benefit analysis Iterative method TOPSIS method
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基于机器学习的100m高度风速短期预报订正方法
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作者 高金兵 曹润东 +2 位作者 于廷照 姚锦烽 申彦波 《太阳能学报》 北大核心 2025年第1期71-77,共7页
提出一种基于机器学习的先格点订正区域误差、后站点订正局地误差的100 m高度风速短期预报订正方法。首先,基于100 m高度风速格点实况资料,采用深度学习算法对数值天气预报进行格点订正;然后,基于测风塔100 m高度风速观测资料,采用随机... 提出一种基于机器学习的先格点订正区域误差、后站点订正局地误差的100 m高度风速短期预报订正方法。首先,基于100 m高度风速格点实况资料,采用深度学习算法对数值天气预报进行格点订正;然后,基于测风塔100 m高度风速观测资料,采用随机森林集成预报订正方法对站点风速预报进行订正;最后,选用内蒙古中部某站点进行分析验证。结果表明,订正前未来84小时风速预报均方根误差(RMSE)为4.25 m/s,格点订正后RMSE降至3.16~3.79 m/s,站点集成订正后RMSE降至2.81 m/s。格点订正后预报误差明显降低,站点集成订正后误差进一步减小。 展开更多
关键词 100m高度风速预报 预报订正 机器学习 深度学习 集成预报
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1 064nm泵浦乙烷1.55μm拉曼激光研究
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作者 王海洋 徐明 +5 位作者 蔡向龙 刘栋 孙景露 钱飞宇 李俊涛 郭敬为 《强激光与粒子束》 北大核心 2025年第1期8-13,共6页
受激拉曼散射(SRS)作为一种高效的激光频率改变方法,受到广泛关注。但是拉曼激光也存在着明显的不足,其波长缺少连续调谐的能力,因此需要开发更多的拉曼活性介质,提高拉曼频移覆盖密度。以波长为1 064 nm的激光作为泵浦源,以高压乙烷作... 受激拉曼散射(SRS)作为一种高效的激光频率改变方法,受到广泛关注。但是拉曼激光也存在着明显的不足,其波长缺少连续调谐的能力,因此需要开发更多的拉曼活性介质,提高拉曼频移覆盖密度。以波长为1 064 nm的激光作为泵浦源,以高压乙烷作为拉曼活性介质,产生了波长为1 550 nm的一阶拉曼(S_(1)),实验过程中未发现明显后向拉曼和高阶拉曼,通过优化实验条件,降低激光诱导击穿(LIB),使S_1的光子转化效率提高到了20.7%,最高脉冲能量达到21.2 mJ。并且首次测量了乙烷对1.55 μm激光的吸收系数和吸收截面,它们分别是5.71×10^(-8) m^(-1)·Pa^(-1)和2.35×10^(-24)cm^(2)。 展开更多
关键词 受激拉曼散射 1.55μm激光 转化效率 吸收系数 乙烷
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China’s Cross-Border E-Commerce: Evolution Pattern and Influencing Factors 被引量:1
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作者 Xie Guo’e Li Xueping 《China Economist》 2020年第2期64-76,共13页
In recent years,while the traditional trade sectors have been shrinking,China’s cross-border e-commerce has undergone rapid development and has become a new driver of its international trade.Based on analysis of the ... In recent years,while the traditional trade sectors have been shrinking,China’s cross-border e-commerce has undergone rapid development and has become a new driver of its international trade.Based on analysis of the evolution pattern of China’s cross-border e-commerce,this paper uses a revised gravity model to test empirically the driving factors and the resistance factors in the development of the country’s cross-border e-commerce.The results show that the total GDP,per capita disposable income of urban residents,total imports and exports,and the scale of the online shopping market have a positive relationship with cross-border e-commerce transactions,which are conducive to the development of cross-border e-commerce,while logistics costs inhibit the development of cross-border e-commerce.Accordingly,the paper puts forward several policy recommendations. 展开更多
关键词 cross-border e-commerce revised gravity model per capita disposable income of urban residents influencing factors
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脂多糖和钛颗粒对种植体周围组织中巨噬细胞M1/M2极化的诱导作用
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作者 邓冉 魏怡 姬晓炜 《中国组织工程研究》 北大核心 2025年第34期7415-7422,共8页
背景:随着种植技术的普及,种植体周围炎的发病率逐年升高,但其病因机制尚不明确。而高度可塑的巨噬细胞在微环境刺激下可极化为M1型和M2型,分别发挥促炎和抗炎作用,在种植体周围组织中发挥宿主防御、免疫应答和维持内环境稳态的重要作用... 背景:随着种植技术的普及,种植体周围炎的发病率逐年升高,但其病因机制尚不明确。而高度可塑的巨噬细胞在微环境刺激下可极化为M1型和M2型,分别发挥促炎和抗炎作用,在种植体周围组织中发挥宿主防御、免疫应答和维持内环境稳态的重要作用,M1/M2巨噬细胞极化趋势与植体周围异物反应平衡息息相关。目的:脂多糖和钛颗粒是引起种植体周围炎的重要致病因素,文章探究其对种植体周围组织中巨噬细胞极化的诱导作用。方法:以“种植体周围炎、巨噬细胞极化、脂多糖和钛颗粒、macrophage polarization、peri-implant inflammation、peri-implantitis、LPS、TLRs、NF-κB等”为关键词在CNKI和PubMed数据库中分别进行检索,对相关文献进行筛选和整理,分析脂多糖、钛颗粒对种植体周围组织中巨噬细胞M1/M2极化的诱导作用和相关机制。结果与结论:①脂多糖和钛颗粒可能通过Toll样受体/核因子κB等相关信号通路诱导植周组织中巨噬细胞极化,引起M1/M2极化失衡从而影响种植体周围炎的发生和进展,部分药物也可通过Toll样受体/核因子κB信号通路调控巨噬细胞M1/M2极化来治疗相关炎性疾病。②通过分析脂多糖、钛颗粒对种植体周围组织中巨噬细胞M1/M2极化的诱导作用,进一步阐述其调控Toll样受体/核因子κB信号通路诱导巨噬细胞极化的作用机制,以期为种植体周围炎的免疫防治研究提供一些新的思路和策略。 展开更多
关键词 种植体周围炎 脂多糖 钛颗粒 TLRs/NF-κB m1/m2 巨噬细胞
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罗汉果苷V调控高糖状态巨噬细胞M1极化促进骨髓间充质干细胞的成骨分化
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作者 叶枝茂 惠久莹 +2 位作者 钟晓霞 麦昱颖 李昊 《中国组织工程研究》 CAS 北大核心 2025年第19期3968-3975,共8页
背景:糖尿病微环境会造成巨噬细胞过度M1极化,这种高糖炎症状态会抑制骨髓间充质干细胞的成骨分化,从而影响糖尿病骨缺损的愈合。研究表明罗汉果苷Ⅴ具有抗炎、抗氧化、降血糖的作用,但其能否调节高糖炎症状态下巨噬细胞M1极化及骨髓间... 背景:糖尿病微环境会造成巨噬细胞过度M1极化,这种高糖炎症状态会抑制骨髓间充质干细胞的成骨分化,从而影响糖尿病骨缺损的愈合。研究表明罗汉果苷Ⅴ具有抗炎、抗氧化、降血糖的作用,但其能否调节高糖炎症状态下巨噬细胞M1极化及骨髓间充质干细胞的成骨分化尚不清楚。目的:探讨罗汉果苷Ⅴ在高糖炎症状态下调节巨噬细胞M1型极化对骨髓间充质干细胞成骨分化的影响。方法:构建糖尿病C57BL/6小鼠模型,从正常和糖尿病小鼠分离骨髓来源巨噬细胞,分别培养于低糖和高糖培养基。使用脂多糖和干扰素γ作为炎症刺激诱导骨髓来源巨噬细胞的M1型极化,同时以160,320,640μmol/L罗汉果苷Ⅴ干预,用流式细胞术检测F4/80^(+)CD86^(+)细胞比例,qRT-PCR检测诱导型一氧化氮合酶、白细胞介素1β、白细胞介素6的mRNA表达水平,ELISA检测骨髓来源巨噬细胞上清液中肿瘤坏死因子α水平。分离C57BL/6小鼠骨髓间充质干细胞,分别使用低糖或高糖成骨诱导液诱导成骨分化,添加M1型巨噬细胞条件培养基作为炎症刺激,以及320μmol/L罗汉果苷Ⅴ干预,成骨诱导14 d后采用qRT-PCR检测碱性磷酸酶、Runt相关因子2、骨钙素、骨桥蛋白的mRNA表达水平,成骨诱导21 d后进行茜素红染色及定量分析。结果与结论:①流式细胞术结果显示320,640μmol/L罗汉果苷Ⅴ组的F4/80^(+)CD86^(+)细胞比例明显低于高糖炎症对照组(P<0.05);②qRT-PCR结果显示160,320,640μmol/L罗汉果苷Ⅴ组的诱导型一氧化氮合酶、白细胞介素6的mRNA相对表达量较高糖炎症对照组显著降低(P<0.05),320,640μmol/L罗汉果苷Ⅴ组白细胞介素1β的mRNA相对表达量较高糖炎症对照组显著降低(P<0.05);③ELISA结果显示160,320,640μmol/L罗汉果苷Ⅴ组的肿瘤坏死因子α分泌水平较高糖炎症对照组显著降低(P<0.05);④320μmol/L罗汉果苷Ⅴ干预后,高糖炎症状态下骨髓间充质干细胞的钙盐沉积增加(P<0.05),且碱性磷酸酶、Runt相关因子2和骨桥蛋白的mRNA相对表达量增加(P<0.05)。结果表明,罗汉果苷Ⅴ可通过抑制高糖炎症状态下骨髓来源巨噬细胞的M1型极化及炎症因子表达,促进骨髓间充质干细胞的成骨分化。 展开更多
关键词 罗汉果苷Ⅴ 巨噬细胞 m1型极化 骨髓间充质干细胞 炎症反应 成骨分化 高糖
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