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Dongya Y. Yang Li Liu Xingcan Chen Camilla F. Speller 《Journal of archaeological science》2008,35(10):2778-2785
Recent zooarchaeological studies on water buffalo (Bubalus sp.) remains from China and south Asia question the traditional view that water buffalo were first domesticated in Neolithic China over 7000 years ago. The results from several recent population genetic studies of modern domesticated buffalo (Bubalus bubalis) are not consistent with each other, placing the original center of buffalo's domestication in south Asia, southeast Asia, or China. This paper reports a study using an ancient DNA approach to analyze water buffalo remains from Neolithic sites in north China to investigate their affinities with modern domesticated water buffalo, and to shed light on the origin of modern domesticated water buffalo in China.A 169 bp fragment of D-loop mitochondrial DNA was successfully amplified and verified for 13 of 24 bone samples obtained from seven archaeological sites along the Wei River valley in Shaanxi Province, China. The bone samples which yielded positive DNA can be dated to 8000–3600 cal. BP. The phylogenetic analysis of the obtained DNA sequences along with modern water buffalo sequences indicated that the ancient water buffalos were not the direct ancestor of modern domesticated water buffalo. However, the phylogenetic analysis, along with BLAST searches of these ancient DNA sequences, did demonstrate their relatedness to water buffalo more so than to any other bovid species, confirming the existence of indigenous wild (but now extinct) water buffalo species (B. mephistopheles) in ancient China.The DNA analysis of these ancient remains failed to establish direct links between modern domesticated water buffalo (B. bubalis) and indigenous water buffalo (B. mephistopheles) from ancient China. If further DNA studies of more ancient remains from other regions of China confirm the observation of solely indigenous water buffalo species in ancient China, it would suggest modern water buffalo might not have been first domesticated in China. 相似文献
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Xiaolong Luo Jianfa Shen Wen Chen 《Geografiska annaler. Series B, Human geography》2010,92(4):311-326
During the transition towards a more market‐oriented economy and entrepreneurial governance, local authorities have attempted to create new cross‐jurisdiction regional entities to enhance their competitiveness through making city‐region plans or regional strategic plans in China. This article analyses the process of region building in China through a case study of Nanjing city‐region. We argue that region building is a state‐led regional project in China, not a spontaneous process. City‐region planning has played a legitimacy‐seeking role in the construction of new regions. Based on the discourse provided by the city‐region plan, associated city networks are being created as a mechanism for plan implementation and regional coordination. This signals that regional planning is entering the stage of regional institution building. By assessing the capacity of regional institutions, we argue that the newly‐emerged regional institutions or urban networks have facilitated regionalization in terms of the increasing involvement of non‐state actors, the formation of regional coherence and identity and the enhanced inter‐city co‐operation. However, it is still difficult to establish effective regional governance due to competing local governments, the arbitrary political leadership and the fragmented planning functions. 相似文献
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Recent developments in the biopharmaceutical industry in Taiwan, South Korea and China bear witness to the transformation of these states in nurturing an innovation‐based industry. This article argues that the segmentation of the value chain of the biopharmaceutical industry has provided industrializing countries with a window of opportunity. These East Asian states have modified their former catching‐up approaches by establishing a more effective institutional platform that can attract knowledge‐creation players to the industry. Through case studies, the authors show that the Taiwan state's promotion of the biopharmaceutical industry has been based on an incremental approach; existing state policies have been modified to cope with the demands of the industry, which has resulted in the continuation of its SME‐based industrial structure. The methods of the Korean state have been more radical, in that the policies that previously favoured the chaebols have gradually been reoriented toward the promotion of smaller, science‐based firms that now co‐exist alongside the chaebols. Finally, the Chinese state and local governments have sought to promote this innovation‐based industry by building biotech parks. This approach has resulted in a boom in new science firms, which have become increasingly isolated from the flourishing domestic SOE‐led market. 相似文献
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Ken Frank I‐Chien Chen Youngmi Lee Scott Kalafatis Tingqiao Chen Yun‐Jia Lo Maria Carmen Lemos 《政策研究杂志》2012,40(3):492-515
This study explores how a scientist's location in science‐based policy networks can affect her policy‐oriented behaviors. In particular, we hypothesize that those scientists who fill structural holes in their networks will be more likely than others to engage in policy‐oriented behaviors. The network data are defined by scientists' coauthorship on policy documents regarding climate change in the Great Lakes. We employ a two‐mode network analysis to identify clusters of scientists who coauthored similar documents, and relative to those clusters, we identify those who fill structural holes by bridging between clusters. We find that those scientists who bridged between clusters were more likely to engage in policy‐oriented behaviors of policy advocacy and advising than were others in the network. This is an example of a link between network location and policy‐oriented behavior indicative of the broader phenomenon of how individuals exert agency, given structural constraints. 相似文献
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广东五邑地区以潭江流域为中心,是一个相对独立的地理单元,但该地的政区边界却打破了自然山川的界限。从明代到清初顺治年间,为了应对以民变为首的地方政治危机,朝廷先后在潭江流域设置了恩平、新宁、开平三县。这些县级政区的边界大致与潭江流域的地理分界线重合,地理单元的独立性开始作用于政区划界中。清代雍乾年间,形成了新会、鹤山、新宁、开平、恩平五县分治潭江流域的格局。同时,随着新会县核心政区地位的巩固,流域内各县整合为一个统县政区的倾向开始加强,为后世潭江流域的政区整合奠定基础。明清时期潭江流域的政区变迁体现了地理环境和地方政治局势在政区格局形成过程中的根本性作用。 相似文献