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81.
Recent excavations in south‐eastern Wadi ‘Araba in Jordan have revealed the first early Islamic‐period copper‐smelting site known in the eastern side of the valley, which extends south of the Dead Sea to the Gulf of ‘Aqaba. Five test pits were excavated in 2012 at Khirbat al–Mana‘iyya, a prominent copper‐smelting camp in south‐eastern Wadi ‘Araba, Jordan. The results of these excavations demonstrate that the site was primarily active in the seventh–ninth century AD. Its distance from the copper sources of south‐west ‘Araba suggests that its location was chosen based on proximity to wood and water resources, rather than copper ore deposits. The discovery that the site dates to the early Islamic period has implications for previous and future work in south‐east ‘Araba. In particular, it challenges the common—until now—view of the region as virtually devoid of settlement during this period.  相似文献   
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UNDERSTANDING RELIGIOUS CHANGE between the collapse of the Roman Empire and the Reformation forms one of the cornerstones of medieval archaeology, but has been riven by period, denominational, and geographical divisions. This paper lays the groundwork for a fundamental rethink of archaeological approaches to medieval religions, by adopting an holistic framework that places Christian, pagan, Islamic and Jewish case studies of religious transformation in a long-term, cross-cultural perspective. Focused around the analytical themes of ‘hybridity and resilience’ and ‘tempo and trajectories’, our approach shifts attention away from the singularities of national narratives of religious conversion, towards a deeper understanding of how religious beliefs, practices and identity were renegotiated by medieval people in their daily lives.  相似文献   
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Policy Bubbles     
We develop the concept of a policy bubble to capture the notion of long‐term overinvestment in a policy. In sketching the relation of policy bubbles to economic bubbles, we describe how these two concepts have similar origins but different trajectories because they are filtered by different institutions. We examine in some detail three likely instances of ongoing policy bubbles: crime policy, school reform (charter schools and private education vouchers), and the contracting and privatization of public services. We show how these cases differ from the housing bubble of 1997–2007, how they differ from each other, and the extent to which they can be considered policy bubbles. Last, we suggest this concept can help unify the policy process literature with the practice of policy evaluation and outline testable hypotheses for future research.  相似文献   
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Studies of political attention often focus on attention to a single issue, such as front‐page coverage of the economy. However, examining attention to a single issue without accounting for the agenda as a whole can lead to faulty assumptions. One solution is to consider the diversity of attention; that is, how narrowly or widely attention is distributed across items (e.g., issues on an agenda or, at a lower level, frames in an issue debate). Attention diversity is an important variable in its own right, offering insight into how agendas vary in their accessibility to policy problems and perspectives. Yet despite the importance of attention diversity, we lack a standard for how best to measure it. This paper focuses on the four most commonly used measures: the inverse Herfindahl Index, Shannon's H, and their normalized versions. We discuss the purposes of these measures and compare them through simulations and using three real‐world datasets. We conclude that both Shannon's H and its normalized form are better measures, minimizing the danger of spurious findings that could result from the less sensitive Herfindahl measures. The choice between the Shannon's H measures should be made based on whether variance in the total number of possible items (e.g., issues) is meaningful.  相似文献   
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While the use of radiogenic strontium isotope values to examine paleomobility is increasingly common in the Andes, and beyond, many questions about baseline variability remain. To better understand baseline radiogenic strontium isotope compositions in the Andes, we present new 87Sr/86Sr values from Peruvian soil samples. Modern soil samples were collected from agricultural fields from the following areas in central and southern Peru: Arequipa, Atico, Camaná, Chala, Cusco, Ica, Ilo, Lima, Mejía, Moquegua, Nazca, Ocoña, Palpa, Pisco, Puno, Tacna, and Yauca. Samples were partially dissolved to better approximate the bioavailable strontium. Radiogenic strontium isotope values from the partially dissolved soil samples range from 87Sr/86Sr?=?0.70202 to 0.71894 and, for all soil samples, have a mean of 87Sr/86Sr?=?0.70773?±?0.00166 (1σ, n?=?114). In general, the 87Sr/86Sr values measured for soil samples collected from modern agricultural fields reflect the expected 87Sr/86Sr values based on bedrock geology. Comparing our new soil data with published radiogenic strontium isotope data for bedrock, soil, water, and faunal samples provides constraints on the regions in the Andes that can, and cannot, be distinguished through radiogenic strontium isotope analysis.  相似文献   
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