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风险投资进入时间、技术偏好对创新绩效影响——基于创业板制造业企业的PSM检验 被引量:22
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作者 成力为 邹双 《科研管理》 CSSCI CSCD 北大核心 2019年第7期215-223,共9页
准确评估不同时间进入的风险投资是否具有技术偏好及其对创业企业创新绩效的影响,对我国风险投资的发展和以创新推动产业结构转型升级具有重要意义。本文与进入创业企业的时间联系,考虑其技术偏好,构筑了“风险投资进入时间--技术偏好-... 准确评估不同时间进入的风险投资是否具有技术偏好及其对创业企业创新绩效的影响,对我国风险投资的发展和以创新推动产业结构转型升级具有重要意义。本文与进入创业企业的时间联系,考虑其技术偏好,构筑了“风险投资进入时间--技术偏好--创业企业创新绩效”逻辑链条;并以2009-2012年创业板制造业企业为例,采用PSM方法,分析了不同时间进入企业的风险投资是否具有技术偏好及其对创业企业创新绩效的影响,发现:上市前1年内进入企业的风险投资没有表现出显著的技术偏好,对创业企业创新绩效的动态影响不显著,无论是突破式创新还是渐进式创新;上市前1年以上进入企业的风险投资的技术偏好显著,对创业企业创新绩效存在显著的促进作用,但随着时间推移,对创业企业创新绩效的影响程度越来越小,且对渐进式创新影响的持续性和程度大于突破式创新。 展开更多
关键词 风险投资 异质性创新 倾向得分匹配
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Selective enforcement of regulation 被引量:17
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作者 Donghua Chen Dequan Jiang +1 位作者 Shangkun Liang Fangping Wang 《China Journal of Accounting Research》 2011年第Z1期9-27,共19页
Regulatory agencies may,whether outside of set rules or within their discretion,depart from the original goals or principles set for enforcing the rules,which we term selective enforcement.Taking China,a country in tr... Regulatory agencies may,whether outside of set rules or within their discretion,depart from the original goals or principles set for enforcing the rules,which we term selective enforcement.Taking China,a country in transition,as an example,and using cases and large-sample tests,we present empirical evidence of selective enforcement.The results show that the China Securities Regulatory Commission(CSRC) takes into account whether companies violating the rules have a state-owned background and the strength of that background when investigating and punishing non-compliance.After controlling for the degree of violation,state-owned-enterprises(SOEs) are punished less severely than private companies;and the higher the hierarchy of the SOE in question,the less severe the punishment.It also takes longer for SOEs to be punished.We also find that companies that violate the rules less seriously have a greater tendency to apply for refinancing than those that violate the rules more seriously.This may be because the severity of the violation can affect listed companies' expectations of obtaining refinancing.The analysis and conclusions of this study prove useful in understanding the causes and consequences of selective enforcement in transition economies. 展开更多
关键词 Selective enforcement Government regulation Violations by listed companies State-owned companies Refinancing applications
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Chinese Stroke Association guidelines for clinical management of cerebrovascular disorders:executive summary and 2019 update of the management of high-risk population 被引量:14
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作者 Yilong Wang Shangrong Han +27 位作者 Haiqiang Qin Huaguang Zheng Bin Jiang Yong Cao Yuan Gao Ling Guan Qian Jia Yong Jiang Yuming Jiao Shuya Li Yapeng Li Zixiao Li Wei Liu Xiaojuan Ru Dongling Sun Haixin Sun Penglian Wang Tingting Wang Lixia Zong Lei Guo Xuewei Xie Yuming Xu Yuyuan Xu Xiaomeng Yang Yingying Yang Mengyuan Zhou Wenzhi Wang Chinese Stroke Association Stroke Council Guideline Writing Committee 《Stroke & Vascular Neurology》 SCIE 2020年第3期270-278,共9页
Aim Cerebrovascular disease is the leading cause of death and disability in China,causing a huge burden among patients and their families.Hence,stroke prevention is critical,especially in the high-risk population.Here... Aim Cerebrovascular disease is the leading cause of death and disability in China,causing a huge burden among patients and their families.Hence,stroke prevention is critical,especially in the high-risk population.Here,we present the evidence-based guideline suitable for the Chinese population.Methods Literature search of PubMed and Cochrane library(from January 1964 to June 2019)was done.After thorough discussion among the writing group members,recommendations were listed and summarised.This guideline was reviewed and discussed by the fellow writing committees of the Chinese Stroke Association’s Stroke.Results This evidence-based guideline was written in three parts:controlling the risk factors of stroke,utilisation of antiplatelet agents and assessing the risks of first-ever stroke.All recommendations were listed along with the recommending classes and levels of evidence.Conclusions This guideline provides recommendations for primary prevention of cerebrovascular disease among high-risk population in China.Controlling related risk factors,appropriately using antiplatelet agents,assessing the risk of developing first-ever stroke should help reduce the rate of cerebrovascular disease in China. 展开更多
关键词 prevention listed high
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A CATALOGUE OF THE SEAGRASSES OF CHINA 被引量:12
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作者 C.den Hartog 杨宗岱 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1990年第1期74-91,共18页
In this overall survey of the seagrasses of China 15 species are listed, eight of which are recorded for the first time. The Potamogetonaceae (subfamilies Zosteroideae and Cymodoceoideae) are represented by 10 species... In this overall survey of the seagrasses of China 15 species are listed, eight of which are recorded for the first time. The Potamogetonaceae (subfamilies Zosteroideae and Cymodoceoideae) are represented by 10 species, and the Hydrocharitaceae (subfamilies Vallisnerioideae, Thalassioideae and Halophiloideae)by 5 species. Halophila ovalis (R.Br.) Hook, f. is represented by 2 subspecies. A key to the species based on vegetative and generative characteristics is presented. 展开更多
关键词 SUBSPECIES VEGETATIVE SHEATH generative brown leaved FLOWERING listed narrow fibres
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Determination of carbendazim in tea using surface enhanced Raman spectroscopy 被引量:10
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作者 Chun-Hua Ma Jing Zhang +2 位作者 Yong-Cong Hong Yi-Ru Wang Xi Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第12期1455-1459,共5页
Surface-enhanced Raman scattering(SERS) is applied to detect the concentration of carbendzim(CBZ) in tea leaves. Au colloid is selected and used for active surfaces, and the extraction conditions are optimized in ... Surface-enhanced Raman scattering(SERS) is applied to detect the concentration of carbendzim(CBZ) in tea leaves. Au colloid is selected and used for active surfaces, and the extraction conditions are optimized in the experiment. The linearity range for the SERS intensity and the concentration of CBZ is found to be0.5 to 8 mg kgà1. The detection limit for CBZ is 0.1 mg kgà1and its recovery in tea samples is 72.3%. The detection results for CBZ using this method are compared with those of HPLC, and no obvious difference can be found. In addition, by dripping the condensed Au colloid on the tea leaves, the proposed SERS approach could be used to the in-situ determination of the half life period of CBZ on tea leaves. 展开更多
关键词 SERS colloid linearity pesticide condensed filtered preparations listed attributed consuming
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First record of the golden potato nematode Globodera rostochiensis in Yunnan and Sichuan provinces of China 被引量:6
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作者 JIANG Ru PENG Huan +9 位作者 LI Yun-qing LIU Hui ZHAO Shou-qi LONG Hai-bo HU Xian-qi GE Jian-jun LI Xing-yue LIU Miao-yan SHAO Bao-lin PENG De-liang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第3期898-899,共2页
The potato cyst nematodes(PCN) Globodera rostochiensis(Wollenweber) Skarbilovich,1959 is considered the most damaging nematode pest of potato worldwide that causes significant yield losses,and this nematode is recogni... The potato cyst nematodes(PCN) Globodera rostochiensis(Wollenweber) Skarbilovich,1959 is considered the most damaging nematode pest of potato worldwide that causes significant yield losses,and this nematode is recognized and listed as a quarantine nematode in many countries(EPPO 2017).China is currently the largest producer of potato in the world. 展开更多
关键词 listed NEMATODE record
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流动性与地理因素:基于中国上市公司的实证研究 被引量:5
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作者 余兆纬 吴卫星 +1 位作者 Zhao-wei Wei-xing 《科学决策》 2010年第12期53-60,共8页
针对地理因素研究了我国股市的流动性特征。首先按GDP排名把31个省市划分成经济发展程度有差异的两类,在此基础上构建虚拟变量代表地理因素,分别把交易量、换手率和流动性度量指标作为被解释变量,研究上市公司股票流动性和地理因素之间... 针对地理因素研究了我国股市的流动性特征。首先按GDP排名把31个省市划分成经济发展程度有差异的两类,在此基础上构建虚拟变量代表地理因素,分别把交易量、换手率和流动性度量指标作为被解释变量,研究上市公司股票流动性和地理因素之间相关性的存在性以及其显著程度。研究结果表明地理因素对交易量没有影响,对换手率和流动性有一定的影响,"发展中"省市公司在流动性方面相对于"发达"省市公司表现出明显的差异。 展开更多
关键词 流动性特征 地理因素 中国上市公司 实证研究 listed COMPANIES 经济发展程度 交易量 换手率 股票流动性 被解释变量 因素研究 虚拟变量 公司表现 度量指标 差异 存在性 排名 结果 基础 划分
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New Quality Productive Forces:Future Driving Force of China's Economy
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作者 Zhao Ailing 《China's Foreign Trade》 2024年第2期25-28,共4页
The new quality productive force is undoubtedly one of the biggest focuses during this year's Two Sessions,and was not only included in the government work report for the first time,but was also listed as one of t... The new quality productive force is undoubtedly one of the biggest focuses during this year's Two Sessions,and was not only included in the government work report for the first time,but was also listed as one of the top ten tasks in terms of government work in 2024. 展开更多
关键词 listed DOUBT ECONOMY
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Dynamic analysis on pressure fluctuation in vaneless region of a pump turbine 被引量:6
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作者 LI DeYou GONG RuZhi +3 位作者 WANG HongJie XIANG GaoMing WEI XianZhu LIU ZhanSheng 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第5期813-824,共12页
As the pump turbine tends to be operated with high head and high rotational speed, the study of stability problems becomes more important. The pump turbine usually works at operating conditions where the guide vanes e... As the pump turbine tends to be operated with high head and high rotational speed, the study of stability problems becomes more important. The pump turbine usually works at operating conditions where the guide vanes experience strong vibrations. However, most traditional studies were carried out based on constant GVO(guide vane opening) simulations. In this work, dynamic analysis on pressure fluctuation in the vaneless region of a pump turbine model was conducted using a dynamic mesh method in turbine mode. 3D unsteady simulations were conducted where GVO was closed and opened by 1° from the initial 18°. Detailed time domain and frequency domain characteristics on pressure fluctuation in the vaneless region under different guide vane rotational states compared with constant GVO simulations were investigated. Results show that, during the guide vanes oscillating process, the low and intermediate frequency components in the vaneless region are significantly different. The amplitudes of pressure fluctuation are higher than those with constant GVO simulations, which agree better with the experimental data. In addition, the pressure fluctuation increases when GVO is opened, and vice versa. It can be concluded that pressure fluctuation in the vaneless region is strongly influenced by the oscillating of the guide vanes. 展开更多
关键词 fluctuation turbine agree unsteady listed operated opened creased Figure inlet
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Glory Days
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作者 Yi Ziyi Gu Xin 《China Weekly》 2024年第3期48-51,共4页
Directed by Hong Kong filmmaker Wong Kar-wai,acclaimed TV shew Blossoms Shanghai portrays Gatsby-estue vignettes from the 9os that have stirred a nationwidenostalgia for China's economic heyday.Jazz and blues seep... Directed by Hong Kong filmmaker Wong Kar-wai,acclaimed TV shew Blossoms Shanghai portrays Gatsby-estue vignettes from the 9os that have stirred a nationwidenostalgia for China's economic heyday.Jazz and blues seep from the softly lit bars.The latest pop hits from Hong Kong swell through the bustling restaurants as neon lights contend for customers on the streets.A few blocks away,quiet alleys are drenched in pale streetlight,where men in bespoke suits chat about newly listed stocks. 展开更多
关键词 NATIONWIDE listed RESTAURANT
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班夫国家公园:落基山脉的明珠
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作者 孙启禄 《疯狂英语(新读写)》 2024年第9期26-30,75,76,共7页
Established as a national park in 1887,Banff National Park occupies 2564 square miles(almost 6641 square kilometers)along the eastern slopes of the Rocky Mountains and borders British Columbia.Noted for its beauty,pla... Established as a national park in 1887,Banff National Park occupies 2564 square miles(almost 6641 square kilometers)along the eastern slopes of the Rocky Mountains and borders British Columbia.Noted for its beauty,plant and animal diversity,and ongoing geologic processes,Banff National Park was listed as part of the Canadian Rocky Mountain Parks UNESCO World Heritage site in 1984. 展开更多
关键词 listed GEOLOGIC UNESCO
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Strengthen Core Competitiveness with New QualityProductive Forces——Review of 2023 Reform and Development Achivements Made by CSSC Controlled Listed Companies
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作者 Liu Zhiliang 《船舶经济贸易》 2024年第6期58-62,共5页
China State Shipbuilding Corporation(CSSC)has attached great importance to the capital market,and always taken listed companies as an effective means to boost the development of its main business and optimize the allo... China State Shipbuilding Corporation(CSSC)has attached great importance to the capital market,and always taken listed companies as an effective means to boost the development of its main business and optimize the allocation of resources.Afteryears of efforts,the listed companies have become the basic force and power source to continuously promote the high-quality development of CSSC. 展开更多
关键词 COMPANIES listed ATTACHED
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Clinical profile and risk factors of Strongyloides stercoralis infection
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作者 Rupak Chatterjee Alisha Acharya +4 位作者 Subhoroop Ghosh Shatavisa Mukherjee Tapashi Ghosh Nandini Chatterjee Netai Pramanik 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第1期43-44,共2页
Strongyloides(S.)stercoralis,endemic in tropical and subtropical countries,is a soil-transmitted geohelminth human parasite belonging to a group of nematodes called roundworms.S.stercoralis is one of the most overlook... Strongyloides(S.)stercoralis,endemic in tropical and subtropical countries,is a soil-transmitted geohelminth human parasite belonging to a group of nematodes called roundworms.S.stercoralis is one of the most overlooked parasitic infections enlisted among the WHO"neglected tropical diseases"[1].S.stercoralis mainly infects humans but can also be found naturally in domestic dogs,cats,and some primates. 展开更多
关键词 TROPICAL SUBTROPICAL listed
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Snapshot Survey of the Presence of Perfluoroalkyl Substances in Products, Articles, and the Environment in Ecuador
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作者 Heidelore Fiedler Luis Vega-Bustillos +2 位作者 Jenny Arias-Pastrano Lander Vinicio Pérez-Aldás Jose Castro-Díaz 《Engineering》 SCIE EI CAS CSCD 2024年第6期49-61,共13页
The Stockholm Convention on Persistent Organic Pollutants(POPs)is a legally binding instrument for 186 Parties(status:April 2023).Accordingly,among other responsibilities,countries are obliged to report the production... The Stockholm Convention on Persistent Organic Pollutants(POPs)is a legally binding instrument for 186 Parties(status:April 2023).Accordingly,among other responsibilities,countries are obliged to report the production,import,or export of the POPs listed in Annexes A,B,or C;provide information to registers;maintain inventories;and monitor the presence of POPs in the environment.In the broader context of international chemicals and waste management,producer responsibilities,harmonized reporting,and compliance with national and international regulations,Ecuador has addressed the newly listed group of perfluorinated alkyl substances(PFAS)in its national implementation plan and sent selected products from its national market for PFAS analysis.The products analyzed came from the initially listed fields of specific exemptions and acceptable purposes,including:fire-fighting foams;photographic aids;greasers/degreasers;various kinds of paper/packaging;textiles;and leather,coatings,cleaners,metal plating,and pesticides.Our results showed that the three PFAS presently listed in the Stockholm Convention could be quantified in only a few samples;additional PFAS,not yet listed in the Convention also had low detection frequencies.Although the number of samples was limited,the samples covered a large spectrum of sample matrices,making it possible to conclude that—once these products become waste and are regulated under the Basel Convention—they would not constitute a disposal problem.Nevertheless,verification of the presence of PFAS in products on the market is expected to pose an analytical challenge for both,developed and developing countries. 展开更多
关键词 Emerging or newly listed POPs Stockholm Convention Products and articles PFAS analysis Developing countries
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Qujialing Relics Site:Testament to Civilization in Middle Reaches of Yangtze River
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作者 Tao Yang 《China News Release》 2024年第6期102-105,共4页
China released a list of the top 10 archaeological findings of 2023 on March 22,2024,with the Qujialing relics site in central China's Hubei Province listed as one of them.The Qujialing relics site dates back betw... China released a list of the top 10 archaeological findings of 2023 on March 22,2024,with the Qujialing relics site in central China's Hubei Province listed as one of them.The Qujialing relics site dates back between 5,900 and 4,200 years and is a major Neolithic relics site.Located in the transition belt between the southern foothills of Dahong Mountain and the Jianghan Plain,with Qujialing at its core,the site occupies an area of approximately 2.84 million square meters,integrating over 10 spots,including Yinjialing,Zhongjialing and Zhongziba. 展开更多
关键词 YANGTZE MIDDLE listed
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Post-Superstar Era
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作者 Zhang Shasha 《Beijing Review》 2024年第33期36-37,共2页
On July 25,Dong Yuhui,one of China's most popular livestreamers,announced his resignation as a senior partner at Easy Buy,a live-commerce platform.He said he will run his namesake venture Time With Yuhui independe... On July 25,Dong Yuhui,one of China's most popular livestreamers,announced his resignation as a senior partner at Easy Buy,a live-commerce platform.He said he will run his namesake venture Time With Yuhui independently,Dong made the decision due to his own career aspirations,commitment to his other pursuits and personal time arrangements,Hong Kong-listed East Buy said in a filing with the Hong Kong Stock Exchange. 展开更多
关键词 VENTURE listed arrangement
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Old Town Vibes
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作者 Mina Yan 《China Weekly》 2024年第5期60-61,共2页
For a taste of traditional Naxi culture as well as stunning scenery,get high on a visit to UNESCO-listed Lijiang,perched at the end of the Himalayas.
关键词 listed UNESCO CULTURE
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价值链视角下中国新能源汽车产业网络及其机制
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作者 何瑶 杨永春 王绍博 《Journal of Geographical Sciences》 SCIE CSCD 2024年第4期779-803,共25页
Based on the data of listed companies in the core industry chain of China's new energy vehicles in 2015 and 2021,this paper constructs their industrial network from the perspective of the value chain,and uses meth... Based on the data of listed companies in the core industry chain of China's new energy vehicles in 2015 and 2021,this paper constructs their industrial network from the perspective of the value chain,and uses methods such as social network and negative binomial regression model to study the characteristics,evolution,differences,and formation mechanisms of different value chain networks.The results show that:(1)R&D-oriented,production-oriented,and service-oriented networks share several common features:These networks are simultaneously expanding in scale and transitioning towards more efficient“small world”network;The degree distribution in these networks follows a power-law distribution,indicating a scale-free network structure;There is a decrease in the power-law exponent of network's degree distribution,indicating an increase in network heterogeneity.Furthermore,there is a significant positive correlation between the degrees of nodes in networks with diverse value chains,suggesting that the same node holds a similar level of significance across different networks.(2)The number of power-prestige,power and prestige nodes increases in the networks of all value chain segments,except in the service-oriented network,where there are no power nodes.In each value chain network,these nodes have different agglomeration directions:In R&D-oriented network,the nodes tend to cluster around headquarters and high-level cities.In contrast,service-oriented network shows a concentration of nodes in municipalities,sub-provincial and provincial capitals.Similarly,production-oriented network demonstrates a clustering of nodes in traditional production bases.(3)Different value-added segments of industry form different types of agglomeration in pursuit of different factor endowments and agglomeration effect,and form the spatial structure of the strongest connection industrial network with different characteristics.The R&D-oriented networks have always been an integrated and closely connected multiple core-periphery structure commun 展开更多
关键词 value chain new energy vehicle industry listed company industrial network core-periphery structure
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Comment on “A novel antibiotic class targeting the lipopolysaccharide transporter”
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作者 Ruo-Yi Lv Xiao-Ye Liu 《Pharmacology Discovery》 2024年第2期52-53,共2页
Crisis of antibiotic resistant has become a global threat to public health in recent decades[1–4].Carbapenem antibiotics are a class of atypicalβ-lactam antibiotics with the broadest antibacterial spectrum and the s... Crisis of antibiotic resistant has become a global threat to public health in recent decades[1–4].Carbapenem antibiotics are a class of atypicalβ-lactam antibiotics with the broadest antibacterial spectrum and the strongest antibacterial activity.However,carbapenem-resistant Acinetobacter baumannii(CRAB)is stilly emerging,which is a gram-negative bacterium with lipopolysaccharide(LPS),which makes it resistant to several antibiotics and thus difficult to eliminate[5,6].As the number one pathogen of nosocomial infection,CRAB can cause severe pneumonia and bloodstream infection,etc.The mortality rate of patients infected with invasive CRAB can be as high as 40%to 60%,and it has been listed as the key pathogen of Class 1 by the World Health Organization.Due to the lack of feasible antibiotic strategies,phage combination therapy has been used in some patients,while the efficacy is limited[7].Therefore,new discovery and development of antibiotic that targeting CRAB is urgently demand.Fortunately,Kenneth A. 展开更多
关键词 MORTALITY listed eliminate
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Evolution and Governance of the Structure of Marine Economic Networks in China’s Coastal Areas: Based on Sea-related A-share Listed Companies
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作者 LI Bo CAO Gai 《Chinese Geographical Science》 SCIE CSCD 2024年第5期899-916,共18页
Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linka... Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linkages,the importance of marine economic net-work research is beginning to emerge.The construction of the marine economic network in China’s coastal areas is necessary to change the flow of land and sea resources and optimize regional marine economic development.Employing data from headquarters and branches of sea-related A-share listed enterprises to construct the marine economic network in China,we use social network analysis(SNA)to discuss the characteristics of its evolution as of 2010,2015,and 2020 and its governance.The following results were obtained.1)In terms of topological characteristics,the scale of the marine economic network in China’s coastal areas has accelerated and expan-ded,and the connections have become increasingly close;thus,this development has complex network characteristics.2)In terms of spatial structure,the intensity of the connection fluctuates and does not form stable development support;the group structure gradually becomes clear,but the overall pattern is fragmented;there are spatial differences in marine economic agglomeration radiation;the radi-ation effect of the eastern marine economic circle is obvious;and the polarization effect of northern and southern marine economic circles is significant.On this basis,we construct a framework for the governance of a marine economic network with the market,the government,and industry as the three governing bodies.By clarifying the driving factors and building objectives of marine economic network construction,this study aims to foster the high-quality development of China’s marine economy. 展开更多
关键词 marine economic network sea-related A-share listed companies social network analysis(SNA) network governance China’s coastal areas
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