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East Africa is home to a rich array of stone-tool traditions that span human prehistory. It is unsurprising, therefore, that the region attracted pioneer prehistorians in the early twentieth century, including L. S. B. Leakey, E. J. Wayland and T. P. O’Brien, who created the first cultural framework for East African prehistory during the 1930s. Although aspects of this framework remain relevant today, others have become misunderstood relics of an old classification system that hinders current research. This is particularly evident in the classification of a Later Stone Age (LSA) culture – the Kenya (East African) Aurignacian, later known as Kenya (East African) Capsian. Although this cultural entity was redressed during the 1970s and 1980s and redefined as the Eburran industry, there is still mystique surrounding the current status of the Kenya Capsian, its original scope and definition, the relationship with the Eburran and its position within a modern understanding of the East African LSA. This is largely due to paradigmatic shifts in researcher attitudes, leading to the use of the Eburran as a false proxy. It is necessary now to completely remove the term Kenya Capsian as an indication of similarity among the different LSA technologies. However, there also needs to be less emphasis on the importance of the Eburran and recognition that it is just one example of a multitude of diverse localised LSA industries. This will open the way for future research into the LSA and facilitate our greater understanding of recent prehistory in East Africa.  相似文献   
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Epipaleolithic/early Neolithic settlements at Qinghai Lake,western China   总被引:1,自引:0,他引:1  
Transitions from terminal Pleistocene Upper Paleolithic foraging to Holocene Neolithic farming and pastoralist economic orientations in the northern Tibetan Plateau are examined from the perspective of Epipaleolithic sites located near Qinghai Lake, Qinghai Province, western China. Jiangxigou 2 is an artifact-rich, multicomponent midden site with the main period of occupation dating ca. 9000–5000 cal yr BP, containing abundant flaked stone artifacts including a substantial proportion of microlithic tools, abundant faunal remains including gazelle, deer, and sheep, and a small number of ceramics, including the oldest known on the Tibetan Plateau. Heimahe 3, on the other hand, is a brief hunter's camp dating ca. 8450 cal yr BP, with evident affinities to late Upper Paleolithic camps in the same region that date several thousand years older. The two distinctively different sites are probably nodes within a single Epipaleolithic foraging system that developed on the margins of the high Tibetan Plateau during the early Holocene, and that served as a basis for colonization of the high-altitude Plateau at that time. Jiangxigou 2 appears to be connected to early Neolithic agricultural settlements along the upper Yellow River (Huang He) drainage during the middle Holocene, and may provide insights into forager–agriculturalist interactions that lead to the development of pastoralist systems in the region.  相似文献   
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This article examines changes in the treatment of venereal disease in mid-nineteenth-century France in light of theoretical developments in the understanding of these diseases. It focuses on three theories of venereal disease: the orthodox theory of the "unity" of gonorrhea and syphilis; the physiological theory of Fran?ois Broussais, which essentially denied the actual existence of such a disease; and Philippe Ricord's new doctrine of venereal disease, a theory that is often credited with having established the distinction between syphilis and gonorrhea. The argument is that theoretical considerations played a major role in the evaluation of the relative merits of these theories and that any understanding of the appeal of Ricord's new doctrine must consider not only its pathological claims but its therapeutic implications as well. This was not, however, simply an instance of theory applied. These two aspects of Ricord's new doctrine, its pathology and its therapeutics, were inextricably bound up with one another, so that judgment of the one necessarily entailed judgment of the other. The argument is that therapeutic practice should not be seen simply as a downwind consequence of changes in the theoretical understanding of disease, but rather as an integral part of the process of change. These were the kinds of developments that led doctors to believe that French medicine was making very real progress at mid-century.  相似文献   
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Personal travel time in U.S. urban areas has been stable, clashing with the assertion that urban sprawl greatly lengthens travel. Average commute time rises by 7.7 percent with each cross‐sectional doubling of Metropolitan Statistical Area (MSA) jobs. Using the RELU‐TRAN structural computable general equilibrium model of the Chicago MSA, we simulate the equilibrium effects of a 24 percent population increase projected from 2000 to 2030 by the Chicago Metropolitan Agency for Planning. If no new road capacity is added, then congestion per mile increases. Although the urbanized land area increases by 19 percent, indicating sprawl, the vehicle miles traveled (VMT) per car‐trip decreases by 1.31 percent and the VMT per car‐trip to work decreases by 2.78 percent. Car travel time increases by only 6.25 percent and commuting time by only 4.54 percent, from 30.3 minutes in 2000 to 31.7 in 2030 or 3.4 seconds per year. We further explore the effects of new road capacity, gasoline prices, public transit speed, fuel economy gains, limits on suburban construction, and importantly, the cross‐elasticity of public transit use with respect to car times. The availability of public transportation, economizing on nonwork travel, and land use adjustments that increase job‐residence proximity keep times stable.  相似文献   
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Despite its rich tradition, there are key limitations to researchers' ability to make generalizable inferences about state policy innovation and diffusion. This paper introduces new data and methods to move from empirical analyses of single policies to the analysis of comprehensive populations of policies and rigorously inferred diffusion networks. We have gathered policy adoption data appropriate for estimating policy innovativeness and tracing diffusion ties in a targeted manner (e.g., by policy domain, time period, or policy type) and extended the development of methods necessary to accurately and efficiently infer those ties. Our state policy innovation and diffusion (SPID) database includes 728 different policies coded by topic area. We provide an overview of this new dataset and illustrate two key uses: (i) static and dynamic innovativeness measures and (ii) latent diffusion networks that capture common pathways of diffusion between states across policies. The scope of the data allows us to compare patterns in both across policy topic areas. We conclude that these new resources will enable researchers to empirically investigate classes of questions that were difficult or impossible to study previously, but whose roots go back to the origins of the political science policy innovation and diffusion literature.  相似文献   
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This paper argues for a conception of art as an embodied and creative material practice. It draws on research conducted with seven professional ceramic artists who deal with landscape in their work to explore their processes of art-making through interview and (filmed) observation. It demonstrates the distributed range of embodied and relational more-than-artistic practices which inform how landscape is encountered, known and ultimately represented. It argues that artists’ self-expression in art is based upon material, social and political knowledges which interweave in artists’ lives. By studying ceramicists’ making this paper demonstrates both the non-conscious skill and the conscious technical knowledge needed to make art. It shows chance to have a triple role in practices of making, as something to work alongside, to work against and to draw on as a creative resource. This paper both argues for and demonstrates the value of an approach to art-making that frames it as a complex of both conscious, socio-cultural, technical knowledges and non-conscious skills which together (in)form works of (ceramic) art.  相似文献   
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