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82.
Deciphering patterns and inferring processes in multicausal floodplain river ecosystems is a challenge in river science. The effects of larger‐scale top‐down constraints and smaller‐scale bottom‐up influences on the spatial patterns of nutrient concentrations across multiple inset‐floodplain surfaces was studied in a large dryland floodplain river (Barwon‐Darling River, south‐east Australia). The distribution of sediment‐associated carbon, nitrogen, and phosphorus was primarily related with significant differences in the textural character of the different floodplain surfaces. Elevation of the different floodplain surfaces above the active channel was a secondary influence on the distribution of carbon and phosphorus. Combined, these factors produce a spatial patch mosaic of sediment associated carbon, nitrogen, and phosphorous across these floodplain surfaces. 相似文献
83.
MARTIN A. SMITH 《International affairs》2011,87(6):1385-1399
NATO has been a source of influence on British nuclear policy and strategy since the 1950s. The nature and extent of its influence has, however, been kept limited by successive British governments. This article considers how and why this has happened. It discusses evolving British attitudes towards NATO command and planning, and shows how these were reflected with regard to strategic nuclear issues from the late 1950s. The evolution of the key notion that the United Kingdom is a second centre of nuclear decision within NATO is traced, and both its utility and contradictions are examined. Overall it is argued that, both during and since the Cold War, NATO has neither been a central factor in shaping British nuclear strategy and policy, nor have British nuclear weapons been other than of limited importance and relevance for most NATO members. 相似文献
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The United Nations (UN) and the African Union (AU) have collaborated in building a viable African Peace and Security Architecture and have worked together in a number of armed conflicts over the past decade. Examples include the peace operations in Burundi and Somalia, and the hybrid peace operation in Sudan's Darfur region which is perhaps the most prominent illustration of this collaboration. Although the UN Security Council authorized the intervention in Libya, which was approved by leading regional organizations (the Arab League, the Organization of the Islamic Conference and the Gulf Cooperation Council), it was opposed initially by the AU although the three African states in the Security Council voted for it. Relations cooled as a result and have grown colder still as the UN snubbed the AU and its initial efforts to engage in post‐conflict stabilization in Mali. While the AU sought to prove itself as a capable security provider and partner on the continent with its operation AFISMA, France's Opération Serval and the UN's peace operation for Mali, MINUSMA, bypassed the African Union. This article explores the underlying fault‐lines between the two organizations by examining interactions between the UN and AU since the latter's launch in 2002, but focusing on the Mali case. The fault‐lines emerging from the analysis are different capabilities, risk‐averse vs risk‐assuming approaches to casualties, diverging geopolitics and leadership rivalry. 相似文献
87.
Pudding Pan: a Roman shipwreck and its cargo in context British Museum Research Publication 202 MICHAEL WALSH 189pp, 92 figures,mostly colour, 75 colour plates,British Museum, 2017, £40 (sbk), ISBN 978‐0861592029
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COLIN MARTIN 《International Journal of Nautical Archaeology》2017,46(2):462-463
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Recent terrorist events in the UK, such as the security alerts at British airports in August 2006 and the London bombings of July 2005 gained extensive media and academic analysis. This study contends, however, that much of the commentary demonstrated a wide degree of failure among government agencies, academic and analytic experts and the wider media, about the nature of the threat and continues to distort comprehension of the extant danger. The principal failure, this argument maintains, was, and continues to be, one of an asymmetry of comprehension that mistakes the still relatively limited means of violent jihadist radicals with limited political ends. The misapprehension often stems from the language that surrounds the idea of 'terrorism', which increasingly restricts debate to an intellectually redundant search for the 'root causes' that give rise to the politics of com placency. In recent times this outlook has consistently underestimated the level of the threat to the security of the UK. This article argues that a more realistic appreciation of the current security condition requires abandoning the prevailing view that the domestic threat is best prosecuted as a criminal conspiracy. It demands instead a total strategy to deal with a totalizing threat. The empirical evidence demonstrates the existence of a physical threat, not merely the political fear of threat. The implementation of a coherent set of social policies for confronting the threat at home recognizes that securing state borders and maintaining internal stability are the fi rst tasks of government. Fundamentally, this requires a return to an understanding of the Hobbesian conditions for sovereignty, which, despite the delusions of post-Cold War cosmopolitan multiculturalism, never went away. 相似文献
90.
This paper is concerned with the manufacture and trade of post‐medieval crucibles (14th–19th centuries). The analytical study of crucibles from different contexts in Europe and America employed optical microscopy and SEM–EDS, coupled with archaeological and historical data. We identified two major producers of crucibles, both of them in Central Europe, whose products appear widely distributed internationally. The analytical data allow an explanation of the technical reasons behind their superior reputation, as both crucible types shared comparable material properties, such as thermal, chemical and mechanical stability. Conversely, the two crucible types were radically different in their manufacture and appearance. We argue that, besides technical considerations, sensorial aspects such as texture and colour may have played an important role in the perception and choice of materials. 相似文献