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The clustering of economic activity is believed to generate both positive own‐industry (localization) spillovers and negative competitive pressures. Using data on manufacturing enterprises operating in China during 1998–2006, this paper provides evidence on the net effect of opposing spillovers from nearby economic activity. Central to the analysis is the opportunity to distinguish local manufacturing enterprises by state, private, or foreign ownership. Systematic differences in average productivity of these firms enable inferences about differences in the strength of spillovers from one type of firm to another type. Results indicate that spillovers are larger within the same ownership type than they are across them, consistent with localization economies that operate within segmented channels of influence.  相似文献   
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The growing interest in causal inference in recent years has led to new causal inference methodologies and their applications across disciplines and research domains. Yet, studies on spatial causal inference are still rare. Causal inference on spatial processes is faced with additional challenges, such as spatial dependency, spatial heterogeneity, and spatial effects. These challenges can lead to spurious results and subsequently, incorrect interpretations of the outcomes of causal analyses. Recognizing the growing importance of causal inference in the spatial domain, we conduct a systematic literature review on spatial causal inference based on a formal concept mapping. To identify how to assess and control for the adverse effects of spatial influences, we assess publications relevant to spatial causal inference based on criteria relating to application discipline, methods used, and techniques applied for managing issues related to spatial processes. We thus present a snapshot of state of the art in spatial causal inference and identify methodological gaps, weaknesses and challenges of current spatial inference studies, along with opportunities for future research.  相似文献   
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Southern‐led multilateral development banks (MDBs) play a key role in harnessing global capital to finance the sectors most important to borrowers, especially infrastructure. Two prominent Southern MDBs, the Development Bank of Latin America (CAF) and the Islamic Development Bank (IsDB), have become crucial drivers of regional infrastructure growth. This article explores whether their performance has lived up to their goals of establishing borrower control over bank governance without sacrificing financial dynamism. Using power‐weighted voting indices for member representation on bank boards, the authors determine that these banks offer borrowers much more representation on their boards than do their Northern‐based counterparts, the Inter‐American Development Bank (IDB) and the World Bank International Bank for Reconstruction and Development (IBRD). The article also analyses bank operations to determine whether their governance structure impacts their internal performance, as reflected on balance sheets, and external performance — gaining relevance in development finance and particularly in infrastructure lending, including the burgeoning sector of sustainable (climate‐resilient) infrastructure. The authors find that the CAF and IsDB have become major players in development finance, including in sustainable infrastructure. However, important issues remain in relation to their continued internal capacity development, especially with regard to the environmental and social safeguards necessary to oversee lending.  相似文献   
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The highland plains of western Iran have been investigated with varying intensity. The Sarfirouzabad Plain located in the south of Kermanshah province, although visited perfunctorily, has not previously been studied systematically, despite attractive ecological and environmental conditions. In 2009, a team from Tehran University conducted a systematic and intensive field survey in the region to identify Bronze Age settlements and to assess their location in relation to ecological, environmental and cultural factors that may have impacted their distribution on the plain. The surveyed area was walked in transects at 20‐metre intervals and resulted in the identification of 332 archaeological sites from different cultural periods, which added much to the limited knowledge about the history of this region. Twenty‐four of these settlement sites belong to the Middle and Late Bronze Age horizons. This study uses GIS to map the distribution of archaeological materials and construct spatial models to determine the significance of the distribution patterns of the Bronze Age sites.  相似文献   
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Cleal, C.J., Bhat, G.M., Singh, K.J., Dar, A.M., Saxena, A. & Chandra, S., February 2016. Spondylodendron pranabii—the dominant lycopsid of the late Mississippian vegetation of the Kashmir Himalaya. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

The Sepukhovian fossil floras of the northern margins of Gondwana, on the shores of the Palaeotethys, are dominated by remains of an eligulate, mainly monopodial lycopsid with persistent leaves. The stems show considerable morphological and preservational variation that has historically resulted in the fossils having been assigned to many fossil-species and -genera. However, there is now clear evidence that this simply reflects variation within a single fossil-species, reflecting biological variation and the effects of variable taphonomy, for which the correct taxonomic name is Spondylodendron pranabii (Pal) comb. nov. Part of this morphological variation might have been due to variations in growth rate during the life of the individual plants, which in turn might reflect stressed growing conditions in a wetland habitat. The systematic position of Spondylodendron remains uncertain, owing to the lack of unequivocal evidence of reproductive structures, but it might have affinities with the Sublepidodendraceae.

Christopher J. Cleal [], Department of Natural Sciences, National Museum Wales, Cathays Park, Cardiff CF10 3NP, UK; G.M. Bhat [] and A.M. Dar, Department of Geology, University of Jammu, Jammu, India; Kamal Jeet Singh, [] and Anju Saxena [], Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow-226007, (U.P.) India; Shaila Chandra, Flat Number 105, Beverly Park Apartment 422, New Hyderabad, Lucknow-226007, (U.P.) India.  相似文献   
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This article presents the effects of sediment-damping, impedance-contrast (IC), and size of semi-spherical (SS) basin on the focusing and trapping of the basin-generated surface (BGS) waves and the spatial-variation of average-spectral-amplification (ASA), differential ground motion (DGM), and average-aggravation-factor (AAF). A frequency-dependent focusing of the BGS-wave is inferred. Increase of ASA, DGM, and AAF with increase of size of the SS-basin with a fixed-shape-ratio revealed that the BGS-wave focusing has counter-balanced the sediment-damping effects. It is concluded that the BGS-wave focusing and trapping in the SS-basin is more sensitive to change of IC as compared to the similar change of sediment-damping.  相似文献   
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Vickers-Rich, P., Soleimani, S., Farjandi, F., Zand, M., Linnemann, U., Hofmann, M., Wilson, S.A., Cas, R. &; Rich, T.H. November, 2017. A preliminary report on new Ediacaran fossils from Iran. Alcheringa 42, 231–244. ISSN 0311-5518.

Recent exploratory field mapping of marine sedimentary sequences in the Koushk Mine locality of the Bafq region in Central Iran, and on the northern slopes of the Elborz Mountains south of the Caspian Sea, has yielded large complex body and trace fossils of Neoproterozoic–early Cambrian age. The recovered specimens resemble the previously documented Precambrian discoidal form Persimedusites, and a the tubular morphotype Corumbella, which is a novel occurrence for Iran and otherwise only recorded before from Brazil and the western USA. Additional enigmatic traces can not yet be interpreted unequivocally, but suggest that future work may uncover more unusual Ediacaran fossils from various localities in Central Iran.

Patricia Vickers-Rich* [, ], Faculty of Science, Swinburne University of Technology, Melbourne (Hawthorn), Victoria 3122, Australia; Sara Soleimani [], Palaeontology Department, Geological Survey of Iran, Tehran, Iran; Farnoosh Farjandi [], Department of Geochemical Exploration, Geological Survey of Iran, Tehran, Iran; Mehdi Zand [], Geology Department, Bafq Mining Company, Koushk Mine, Yazd, Iran. Ulf Linnemann [], and Mandy Hofmann [], Senckenberg Naturhistorische Sammlungen, Dresden, Museum für Mineralogie und Geologie, Sektion Geochronologie, Koenigsbruecker Landstrasse 159, D-01109, Dresden, Germany; Siobhan A. Wilson [], School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; Raymond Cas [], School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; Thomas H. Rich? [], Museum Victoria, Exhibition Gardens, PO Box 666, Melbourne, Victoria, 3001 Australia. *Also affiliated with: School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; School of Environmental Sciences, Deakin University, Melbourne (Burwood), Victoria, Australia 3125; Palaeontology Department, Museum Victoria, Carlton Gardens, PO Box 666, Melbourne, Victoria 3001, Australia. ?Also affiliated with: School of Earth, Atmosphere and Environment, Monash University, Melbourne (Clayton), Victoria 3800, Australia; Faculty of Science, Swinburne University of Science and Technology, Melbourne (Hawthorn), Victoria 3122, Australia.  相似文献   
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