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Results of analyses of the photoperiod response gene (PPD-H1) and simple sequence repeats (SSRs) in modern landraces of cultivated barley were used as evidence for the mechanism of agricultural spread in Neolithic Europe. In particular, we explored the usefulness of considering adaptive genes as indicators of past selective pressures acting on crops, during their spread through Europe. In some areas, such as the Alpine region, Britain and Scandinavia, we have evidence to suggest that the adaptation of crops to certain climatic conditions may have contributed to the timing of agricultural spread. At the northern fringes of Europe, and in higher altitude locations in central Europe, the introduction of more suitably adapted cereals may have facilitated successful agriculture to trigger agricultural expansion. This research opens up the possibility of investigating other genetic adaptations to climate, which would permit a fuller evaluation of the relative contributions of climate/crop and forager/farmer interactions in the process of agricultural spread.  相似文献   
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ABSTRACT The twenty‐first century will be one of intensified urbanization, on a scale never before experienced. How do urban systems and individual cities change and develop? The social sciences have many different approaches to analyzing the economic, social, and spatial dimensions of urban change. We inventory some of these approaches and their implications for public policy toward cities, urban change, and economic development.  相似文献   
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The relationship between cranial deformation and the occurrence of extra‐sutural bones remains poorly understood. Scholars are divided about whether or not cranial deformation causes an increased occurrence of these bones, and even those who agree that deformation does have an influence often disagree about which locations on the crania are most impacted. Part of this issue clearly stems from the difficulties in finding appropriate samples from which to test the hypothesis that deformation leads to an increased expression of extra‐sutural bones. The present study examines the effects of fronto‐occipital and occipital‐only deformation on the occurrence of extra‐sutural bones through an analysis of 59 deformed and undeformed crania from the Philippines. Relative to the undeformed crania, both deformed samples showed an elevated number of extra‐sutural bones. Using two different statistical tests, we identified a significantly higher occurrence of extra‐sutural bones at two distinct cranial localities for both the fronto‐occipitally deformed crania (coronal suture and asterion) and for those showing only occipital flattening when compared to the undeformed crania (lambdoidal and asterion). However, as our data reveal, individuals with highly elevated occurrences of extra‐sutural bones are not necessarily deformed. As such, we argue that deformation practices may have a positive impact on the formation of extra‐sutural bones; however, future studies using larger samples of deformed and undeformed crania—ideally from the same site—will be necessary to distinguish between the influence of cranial deformation on extra‐sutural bone formation relative to other population factors which may play a role in shaping variation in this feature. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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Archaeological fish bones reveal increases in marine fish utilisation in Northern and Western Europe beginning in the 10th and 11th centuries AD. We use stable isotope signatures from 300 archaeological cod (Gadus morhua) bones to determine whether this sea fishing revolution resulted from increased local fishing or the introduction of preserved fish transported from distant waters such as Arctic Norway, Iceland and/or the Northern Isles of Scotland (Orkney and Shetland). Results from 12 settlements in England and Flanders (Belgium) indicate that catches were initially local. Between the 9th and 12th centuries most bones represented fish from the southern North Sea. Conversely, by the 13th to 14th centuries demand was increasingly met through long distance transport – signalling the onset of the globalisation of commercial fisheries and suggesting that cities such as London quickly outgrew the capacity of local fish supplies.  相似文献   
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This article focuses upon the investitures of Emperor Charles VI in 1717 in Brabant and Flanders. The purpose of this analysis is to demonstrate that, contrary to what some historians have claimed, the element of direct communication between prince and subjects remained significant at least until the beginning of the eighteenth century. Despite Charles' assertive attitude, the ceremonies were preceded by a period of intense negotiation, in which the Estates made clear demands. Eventually, however, he acquiesced to some of their requests. These concessions can be placed within a long tradition of modus vivendi between princely centralism and local autonomy in the Southern Netherlands. The sovereign was financially dependent on the Estates, which therefore had a great deal of leverage at their disposal. This vulnerability was compounded by the fact that Charles stood at the head of a dynasty, the Austrian Habsburgs, which had no tradition of authority in these regions upon which to draw. Furthermore, the Barrier Treaty's provisions restricted his sovereignty. His bargaining position influenced the organisation of the investitures, thus illustrating that in the early eighteenth century, the sovereign and provincial Estates of the Southern Netherlands were still engaged in a contractual relationship.  相似文献   
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In 2003, three proposals were being mediated through the planning system in the peri‐urban environment of St Andrews, Fife: a large housing development, a rail link, and a Green Belt. Using questionnaires and semi‐structured interviews with key stakeholders, we investigate the ways in which diverse conceptions of ‘the environment’ shaped public reactions to these proposals, and evaluate the fit between these and the respondents’ stated environmental perceptions. 98% of local residents surveyed describe themselves as ‘concerned about the environment’. However, large majorities conceive of the environment as a local rather than a global phenomenon, and regard it primarily in terms of personal benefits (such as landscape aesthetics or traffic considerations). By exploring the environmental perceptions in the light of the planning proposals, the study supports the contention that the ‘local environment’ is a socially constructed phenomenon which can be fashioned and re‐fashioned according to local perceptions of threats and opportunities.  相似文献   
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