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111.
The rapid and unpredictable changes in the Middle East collectively known as the “Arab Spring” are posing tremendous challenges to U.S. policy formation and action. This article will explore and evaluate evolving U.S. policy in the Middle East and its potential implications. There has always been a tension in American foreign policy between pursuing American “values” (foreign policy idealism) and protecting American “interests” (foreign policy realism). For decades, the United States has sought to “make the world safe for democracy,” while at the same time often supporting repressive, nondemocratic regimes because of national security or economic self‐interest. The tension between these two fundamentally distinct policy orientations has become even more pronounced as the United States tries to respond to the Arab Spring uprisings. Why did the United States actively support the rebels in Libya but not the protestors in Syria or Bahrain? Is there an emerging, coherent “Obama Doctrine” on intervention in Arab countries, or was Libya just a “one‐off” event? These are some of the questions that this article will attempt to answer.  相似文献   
112.
The Minjiang River terrace along the Longmen Shan fault zone near Wenchuan, at the eastern margin of the Tibetan Plateau, China, provides archives for tectonic activity and quaternary climate change. However, previous studies were not able to provide ages older than 100 ka due to the limitations of dating material or/and methods applied to date the fluvial sediments. In this study, we used the ESR signal of the Ti-Li center in quartz to obtain the ages of four higher terraces (T3–T6). According to the results, the terraces T3 to T6 were formed at 64±19 ka, 101±15 ka, 153±33 ka, and 423±115 ka, respectively. Combined with previous studies, these results indicate that the formations of all terraces correspond to glacial/interglacial transition periods, such as, T1-T5 being correlated to MIS2/1, MIS4/3, MIS5d/5c, and MIS6/5e respectively, while T6 probably to MIS12/11. According to these data, it is found that the average incision rate was significantly higher over the last 150 ka than that previous 100 ka (250 to 150 ka). As both tectonics and climate have affected the formation of these terraces, in addition to the overall uplifting of Tibetan Plateau, the regional uplift due to isostasy would be an additional tectonic factor in the formation of river terraces in the eastern margin of Tibetan plateau.  相似文献   
113.
Australia is currently negotiating a framework treaty with the European Union (EU) that aims at closer cooperation on a wide range of shared policy goals. The treaty is not expected to include trade-liberalisation commitments. This article queries why this is, given the importance of trade and business relations with the EU for Australia, and the fact that the EU exerts international influence primarily as a trade power, rather than a foreign and security policy power. Since 2006, the EU has also been negotiating ‘new-generation’ bilateral free trade agreements (FTAs), focusing on tariffs and regulatory non-tariff trade barriers. It has now committed itself to FTA negotiations with many of Australia's trade partners in Asia and the Organisation for Economic Co-operation and Development. An FTA and a complementary framework treaty were concluded with South Korea in 2010, and the EU is currently negotiating a similar package with Canada. As Australia and Canada are comparable trade partners for the EU, the article argues that an FTA on the EU–Canada model could be a more effective avenue for Australia to achieve deeper engagement with the EU.  相似文献   
114.
Fractal geometry can be used for determining the morphological boundaries of metropolitan areas. A two‐step method is proposed here: (1) Minkowski's dilation is applied to detect any multiscale spatial discontinuity and (2) a distance threshold is located on the dilation curve corresponding to a major change in its behavior. We therefore measure the maximum curvature of the dilation curve. The method is tested on theoretical urban patterns and on several European cities to identify their morphological boundaries and to track boundary changes over space and time. Results obtained show that cities characterized by comparable global densities may exhibit different distance thresholds. The less the distances separating buildings differ between an urban agglomeration and its surrounding built landscape, the greater the distance threshold. The fewer the buildings that are connected across scales, the greater the distance threshold.  相似文献   
115.
There has been relatively little comparative research undertaken on sub‐national cultural policy. This article aims to contribute to the development of sub‐national comparative studies by assessing the utility of national cultural policy approaches for comparative research at the sub‐national level in Canada. Drawing on studies of national cultural policy, the authors develop three main approaches to cultural policy and administration – the French, British and hybrid approaches – and explore their applicability to the origin and evolution of cultural policy and administration in the Canadian provinces of Québec and Ontario. This exploratory research suggests there is room for optimism in drawing on national‐level experiences to undertake sub‐national comparative cultural policy research, particularly for comparisons over broad time periods. The study also suggests that it will be important in subsequent research to further elaborate the models for present‐day comparative analysis and to refine and adapt them to reflect specificities at the provincial level of analysis.  相似文献   
116.
117.
This article surveys the legislation concerning the residence of colonial slaves and nonwhites in general in eighteenth-century France. On the one hand, it shows an increasing concern with race on the part of the elite, heavily influenced by colonial attitudes, leading to laws increasingly reminiscent of apartheid; on the other hand, it reveals the state's inability to enforce its own regulations in the context of privilege, resulting in a legal confusion typical of late ancien-ŕegime law.  相似文献   
118.
Geostatistical methods have rarely been applied to area-level offense data. This article demonstrates their potential for improving the interpretation and understanding of crime patterns using previously analyzed data about car-related thefts for Estonia, Latvia, and Lithuania in 2000. The variogram is used to inform about the scales of variation in offense, social, and economic data. Area-to-area and area-to-point Poisson kriging are used to filter the noise caused by the small number problem. The latter is also used to produce continuous maps of the estimated crime risk (expected number of crimes per 10,000 habitants), thereby reducing the visual bias of large spatial units. In seeking to detect the most likely crime clusters, the uncertainty attached to crime risk estimates is handled through a local cluster analysis using stochastic simulation. Factorial kriging analysis is used to estimate the local- and regional-scale spatial components of the crime risk and explanatory variables. Then regression modeling is used to determine which factors are associated with the risk of car-related theft at different scales.  相似文献   
119.
Simplistic interpretations of the impact of newcomers on South American ecosystems retain currency in the environmental history of the subcontinent. European settlement is almost invariably seen to produce a continuous and linear destruction of the environment. On the basis of several crisis narratives contained in historical documents, it is widely accepted that there was a severe decrease in the extent of woody vegetal formations in the Río de la Plata area during the 19th and 20th centuries. To test this perception, and to develop a more accurate and more complex analysis of the environmental consequences of European occupation, this article focuses on Uruguayan territory from c. 1800 to 2000. Changes in the shape and extent of forest lands in this broad area were assessed by comparing 251 land-survey charts, drawn between 1830 and 1860, with modern-day forest maps. Changes in shrubland abundance were assessed by comparing current distributions with those inferred from the accounts of five travellers who passed through this territory in the first half of the 19th century. Over 200 years, there is no evidence of major changes in forest distribution, extent or shape, and shrublands appear to be much more abundant today than in the early 19th century. These observations, although based on limited data, contradict the most common interpretation of regional environmental evolution. They confirm other claims that the idea of forest destruction in the early 19th century was created and manipulated by actors involved in land conflicts. Close examination of such socially-constructed crisis narratives, through the use of new archives, leads to a better understanding of recent changes in the South American environment.  相似文献   
120.
New excavations have been undertaken at Diepkloof Rock Shelter (DRS; South Africa) since 1999. It is one of the very few sites where Howiesons Poort and Stillbay assemblages can be collected from the same archaeological sequence. These Middle Stone Age techno-complexes are particularly interesting for their affinities with the much younger Later Stone Age facies, and their association with evidence for symbolic behaviour. Establishing their chronology is therefore particularly important for the understanding of the apparition and the evolution of the so-called “modern” behaviours. Data already available suggest ages ranging from 55 to 80 ka for the Howiesons Poort and from 70 to 80 ka for the Stillbay techno-complexes in several South African sites. The thermoluminescence dating undertaken at DRS on 22 stone samples originating from the entire stratigraphic record indicates intervals starting 10–50 ka earlier for these techno-complexes in this site. Possible caveats in the dating process are examined but to the best of our current knowledge must be rejected.  相似文献   
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