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Journal of Archaeological Research - The cities of the Indus civilization were expansive and planned with large-scale architecture and sophisticated Bronze Age technologies. Despite these hallmarks...  相似文献   
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Cai, C.-Y., ?lipiński, A. & Huang, D.-Y., 31.3.2015. The oldest root-eating beetle from the Middle Jurassic of China (Coleoptera, Monotomidae). Alcheringa 39,488–493. ISSN 0311-5518.

Jurorhizophagus alienus gen. et sp. nov., a new fossil root-eating beetle, is described and figured based on an exceptionally well-preserved impression fossil from the Middle Jurassic Daohugou beds (ca 165 Ma), Inner Mongolia, northeastern China. It represents the earliest fossil Monotomidae known to date. Jurorhizophagus can not be assigned to either of two subfamilies Monotominae or Rhizophaginae based on the unique combination of many unusual characters, including an 11-segmented antenna with a 3-segmented club, the presence of a distinct frontoclypeal suture and transverse pronotum with a median longitudinal groove. The discovery of a new genus from the Middle Jurassic highlights the antiquity of Monotomidae and provides new information about the phylogenetic relationships between Monotomidae and its allied families.

Chen-Yang Cai [], Di-Ying Huang [] (corresponding author), State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, PR China; Adam ?lipiński [], Australian National Insect Collection, CSIRO National Collections Australia, GPO Box 1700, Canberra ACT 2601, Australia.  相似文献   
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The concept of “advocacy coalitions” is the bedrock of the Advocacy Coalition Framework (ACF), one of the most established and successful approaches for understanding policy processes across the globe. This article revisits and sharpens the conceptual definition of advocacy coalitions. We summarize the lessons from its theoretical emphases under the ACF and specify its five attributes (policy actors, shared beliefs, coordination, resources, and stability). Through this specification, we identify the ideal coalition type and several coalition subtypes. We then clarify and make a distinction between how we think about coalitions as a concept and how we approach coalitions empirically. This article sharpens the lens for describing and explaining coalitions toward better observations, theorizing, and measurements. It ends with next steps for further deepening and broadening knowledge about advocacy coalitions.  相似文献   
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A research project of the German Federal Office for Building and Regional Planning focussed on the role and the perspectives of medium-sized cities in urban regions. Quantitative and qualitative research approaches were combined. The main results concretize the development, the functions and the perspectives of medium-sized cities. Simultaneously, the role of medium-sized cities was investigated in the regional context, considering that in urban regions the hierarchy of large, medium-sized and small cities is overlapped by network structures.  相似文献   
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