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31.
Today, exactly 500 years after the discovery of America, there is still a lot of controversy about the history of syphilis in Europe, especially about the Columbian and pre-Columbian hypotheses. This paper presents evidence for the presence of venereal treponematosis in the late Antiquity in France. The case that we examined comes from the necropolis of Costebelle (3rd-5th centuries AD; Hyères, Var, France). Grave no. 1 contained the well-preserved skeleton of a relatively old woman with the skeletal remains of an approximately 7-month-old fetus in her pelvic cavity. The osseous lesions of the fetal remains can be described in four groups: periosteal appositions on the skull vault (frontal and parietal); signs of periostitis on the long bones (bilateral cortical irregularities, predominantly on the left side, which affect first of all tibiae, femora, fibulae, radii and humeri, particularly in the metaphyseal region); some infraperiosteal detachment reminiscent of an infraperiosteal haematoma surrounding the distal extremity of the left forearm and the left hand; and finally, the irregular lesions of the humeral distal and proximal tibial metaphyses reminded us radiologically of Wimberger's signs. The most probable diagnosis of all the lesions mentioned above is that of a precocious congenital syphilis. This case consists of an argument against the epidemiological theories about the migration of Treponema pallidum from the New World back to the Old World starting at the end of the 15th century.  相似文献   
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Indigenous African sheep genetic resources have been classified into two main groups, fat-tailed and thin-tailed sheep. The fat-tailed sheep are the most widely distributed, being found in a large part of North Africa (from Egypt to Algeria) and in Eastern and Southern Africa (from Eritrea to South Africa). The thin-tailed sheep are present mainly in Morocco, Sudan and in West Africa. African sheep were domesticated outside Africa. They share a common ancestry with European and Asian sheep. Archaeological information supports separate introductions and dispersion histories for the African thin-tailed and fat-tailed sheep. The first sheep entered Africa via the Isthmus of Suez and/or the southern Sinai Peninsula, between 7500 and 7000 BP. They were likely of the thin-tailed type. Fat-tailed sheep entered Africa through its northeastern part and the Horn of Africa. Mitochondrial DNA analysis supports a common maternal ancestral origin for all African sheep, while autosomal and Y chromosome DNA analysis indicates a distinct genetic history for African thin-tailed and sub-Saharan fat-tailed sheep. The main ancestral population of southern African fat-tailed sheep likely originated in East Africa. Further work is needed to assess the possible dispersion of sheep from western Africa to the southern African regions.  相似文献   
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Domestication is an ongoing co-evolutionary process rather than an event or invention. Recent zooarchaeological and animal genetics research has prompted a thorough revision of our perspectives on the history of domestic animals in Africa. Genetic analyses of domestic animal species have revealed that domestic donkeys are descended from African ancestors, opened a debate over the contribution of indigenous aurochs to African domestic cattle, revealed an earlier and possibly exogenous origin of the domestic cat, and reframed our vision of African dogs. Genetic diversity studies and mapping of unique traits in African cattle, sheep, goats, pigs and chickens indicate adaptations to regional environmental challenges and suggest hitherto unknown and complex patterns of interactions both among Africans and with Southwest Asia and other Asian regions on the Indian Ocean. This article argues against the static perspective on domestication as invention and for viewing it as a dynamic, locally based and continuing process.  相似文献   
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European Union directives, along with their transposing arrangements in EU member states, can have unanticipated and sometimes undesirable impacts on certain regions and places. These include impacts on the use of space (e.g. new infrastructure or sprawl), governance, and on wider social, economic or environmental dimensions. Although ex-ante assessment of the potential impacts of EU initiatives has been carried out since 2002 through the European Commission's Impact Assessment procedure and also through national equivalents in some member states, important impacts are still overlooked, frequently because of their territorially heterogeneous nature within and between EU member states. This paper presents the results of the ESPON EATIA research project, in which a new territorial impact assessment methodology was developed for national and regional administrations in EU member states in order to inform their national positions during the negotiation of European draft directives and potentially other policy proposals.  相似文献   
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Foreign relations are the main preoccupation of South African president, Thabo Mbeki. His role perception is dominated by a mission to improve the plight of Africa, and second to that, to act as the Third World's überdiplomat . Under his administration, South Africa's foreign policy has become almost an adjunct of his more holistic diplomatic pursuits. The New Partnership for Africa's Development (NEPAD) is the magnum opus of Mbeki's foreign policy, and the success or failure of this grand design for an African renaissance will determine his legacy and make or break his leadership in South Africa and in the rest of Africa. The success of his NEPAD diplomacy is a daunting task, requiring the support of his African peers, his South African constituency, and the leadership of the developed nations of the world. Dealing with these diverse elements, Mbeki's policy-making oscillates between realism and idealism, and between ideology and interests, giving the impression of a style of a prudent bureaucrat rather than that of a single-minded reformer. In the end, his diplomacy seems to founder because it fails to satisfy the contradictory demands of any of these three constituencies. However, even if NEPAD should fail as a project, its role could be that of a harbinger of a new political and economic era in Africa and the movement away from post-colonial orthodoxy.  相似文献   
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Abstract. This paper estimates the effects of knowledge spillovers on patent growth rates across 335 European regions over the 1989–1999 period. We propose a dynamic model based on an innovation production function. A Bayesian approach is used to take into account area‐specific innovation and spatial spillovers. The estimation of the model proceeds via Markov Chain Monte Carlo simulation. The results show significant positive and negative spatial effects on innovative activity. The model allows for a rich spatial specification, which we illustrate by incorporating transport proximity measured by transportation time between regions to augment the typical spatial proximity measure of connectivity between regions. Doing this produces more pronounced spatial spillovers that exhibit a more polarized spatial pattern than a model relying on spatial proximity alone.  相似文献   
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The study of the mathematics of prehistory cannot be founded on bare archeological data alone; it may be useful to set the archeological documents in context, with the help of comparative ethnography, according to which our own contemporaray or near-contemporary primitive societies can help us understand our prehistoric ancestors. Although once used spontaneously by several historians of mathematics, this approach has been rejected on principle by the recent school of ethnomathematicians. This paper sets out to show, by means of a certain number of examples, that the method can nonetheless yield rewards: on the one hand because it demolishes the fantastic theories so fondly constructed by certain mathematicians, and on the other because it opens up a vast field of research which has so far been vitually unexplored.  相似文献   
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