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The average citizen often does not experience government policy directly, but learns about it from the mass media. The nature of media coverage of public policy is thus of real importance, for both public opinion and policy itself. It nevertheless is the case that scholars of public policy and political communication have invested rather little time in developing methods to track public policy coverage in media content. The lack of attention is all the more striking in an era in which media coverage is readily available in digital form. This paper offers a proposal for tracking coverage of the actual direction of policy change in mass media. It begins with some methodological considerations, and then draws on an expository case—defense spending in the United States—to assess the effectiveness of our automated content‐analytic methods. Results speak to the quantity and quality in media coverage of policy issues, and the potential role of mass media—to both inform and mislead—in modern representative democracy.  相似文献   
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The ‘Southeast Asian Lead Isotope Project’ (SEALIP) is intended to provide reliable geochemical proxies for late prehistoric through early historic (2nd/1st millennium BCE and 1st millennium CE) local, regional, and inter-regional social interactions, in an archaeological arena lacking established ceramic typologies with which to cross modern national boundaries. We present lead isotope characterisations of the three currently known Southeast Asian prehistoric primary (mining/smelting) copper production centres: Phu Lon and the Khao Wong Prachan Valley in Thailand, and the recently discovered Xepon complex in Laos. Kernel Density Estimation shows that these production centres can be clearly distinguished isotopically, as such fulfilling the core tenet of the ‘Provenance Hypothesis’ (Wilson and Pollard, 2001: 508) and permitting SEALIP to proceed as a research programme tracing regional copper/bronze/lead exchange and provenance patterning. In addition we provide a provisional technological reconstruction of copper smelting processes at Phu Lon to complement our more established understanding of the Khao Wong Prachan Valley. Combined lead isotope and technological datasets allow us to tentatively identify trends in the evolution of Southeast Asian metal technologies and of regional social perceptions of metal exchange.  相似文献   
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Low temperature (90–190 °C) hydrothermal experiments have been conducted on seven obsidians where composition of the glass varies significantly in the concentration of structural water within the unhydrated bulk material. Infrared transmission spectroscopy was used to track the diffusion of molecular water into the glass surface as a function of time and temperature. Long-term (60–360 days) hydration sequences at 90 °C show a t0.6 time dependence for the mass uptake of molecular water that forms the hydration layer. The structural water concentration of the unhydrated bulk obsidian is highly correlated with the pre-exponential and activation energy and may be used to estimate the Arrhenius constants. In addition, secondary ion mass spectrometry (SIMS) hydrogen profiling of Napa Glass Mountain obsidian hydrated at 90 °C reveals that the early stages of diffusion exhibit a dynamic behavior that includes a fluctuating hydrogen concentration and a changing diffusion coefficient that slows with time.  相似文献   
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Understanding and alleviating poverty in Africa continues to receive considerable attention from a range of diverse actors, including politicians, international celebrities, academics, activists and practitioners. Despite the onslaught of interest, there is surprisingly little agreement on what constitutes poverty in rural Africa, how it should be assessed, and what should be done to alleviate it. Based on data from an interdisciplinary study of pastoralism in northern Kenya, this article examines issues of poverty among one of the continent's most vulnerable groups, pastoralists, and challenges the application of such orthodox proxies as incomes/expenditures, geographic remoteness, and market integration. It argues that current poverty debates ‘homogenize’ the concept of ‘pastoralist’ by failing to acknowledge the diverse livelihoods and wealth differentiation that fall under the term. The article concludes that what is not needed is another development label (stereotype) that equates pastoralism with poverty, thereby empowering outside interests to transform rather than strengthen pastoral livelihoods.  相似文献   
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This article briefly examines the consequences of the European presence on the Gold Coast, focusing on archaeological, ethnographic, and historical data from the African settlement of Elmina, Ghana. Documentary sources indicate that there was extensive change in sociopolitical institutions, economic relations, and other aspects of Gold Coast society in the centuries following the advent of European trade in the late fifteenth century. Archaeological survey and excavation of some 30 structures at Elmina similarly indicates a great deal of change in construction technology and material culture during the post-European contact period. However, examination of artefact patterning and associations indicates that in certain respects there was little change in terms of people's shared world view and belief systems. This picture can be contrasted with data from sites in other areas which may have experienced a great deal of culture change during the post-European contact period.
Résumé Cet article examine brièvement les conséquences de la présence européenne sur la Côte de l'Or, se penchant plus particulièrement sur les données archéologiques, ethnographiques et historiques du site d'Elmina au Ghana. Les sources documentaries indiquent qu'un changement de grande envergure affectant les institutions socio-politiques, les relations économiques et d'autres aspects de la société de la Côte de l'Or pris place durant les siècles suivant l'arrivée du commerce européen à la fin du quinzième siècle. Un survey archéologique et les fouilles d'environ 30 structures à Elmina, indiquent aussi qu'un changement étendu des techniques de construction et de la culture matérielle s'effectue après la période de contact européen. Toutefois, l'étude de la distribution et des associations des objets, indique que le système de croyance et l'idée du monde partagée par cette société furent peu affectés.Cette image peut être comparée avec les données obtenues sur d'autres sites ayant fait l'expérience d'un changement culturel important pendant la période postérieure aux contacts européens.
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Empirical aspects of the movement of strontium through the food chain suggest that the level of bone strontium can be used as an indicator of the percentage of meat in human diet. In general, skeletal remains from agricultural peoples are expected to have high bone strontium levels relative to hunter-gatherers from the same geographical region because plants contain relatively higher amounts of strontium when compared with animal products. The results of the study described in this paper, however, indicate that the inclusion of molluscs as a component of the diet may produce the opposite of the expected strontium values. Burials from an Archaic (c. 2500 BC) hunting-gathering population excavated from Luo25, an archaeological site in northern Alabama, USA, exhibit a mean bone strontium level ( atomic absorption; neutron activation) that is higher than the mean level from an agricultural Mississippian (c. AD 1400) population ( atomic absorption; neutron activation) that was buried at the same site. The samples were analysed by two techniques (atomic absorption spectrometry and neutron activation analysis) and the results compared favourably; therefore, the results can be accepted as valid rather than being due to technique error. We propose that the ingestion of molluscs, whose meat is known to contain large amounts of strontium, has produced this reversal from expected results.  相似文献   
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Evidence is accumulating that the hominid cranium found in the Petralona cave in 1960 is associated with cave deposits of middle Pleistocene age. If this is so, the fossil is the most complete middle Pleistocene cranium yet discovered and provides important morphological, metrical and radiographic information on the possible evolutionary transition from Homo erectus to Homo sapiens. The classification of the specimen is discussed and it is suggested that a grade system within Homo spaiens should be erected. The Petralona fossil would be allocated to Homo sapiens grade 1 rather than to Homo erectus or to a subspecies of Homo sapiens.  相似文献   
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