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81.
82.
This paper analyses the current structure of the system of European cities and regions, relations within the system and how it is changing. Cluster analysis distinguished eight regional types: metropolitan, semi‐peripheral and peripheral service regions; central, semi‐peripheral, peripheral and collapsed industrial regions; and agricultural regions. The core of European industrial societies proves to be almost identical with the city belt that dominated economic development in pre‐industrial Europe. Two possible paths of change are discussed: delocalization of simpler, labour cost‐intensive activities towards the periphery (delocalization hypothesis), or structural changes in industrial core regions and persisting marginal status in the periphery (restructuring hypothesis). Neither hypothesis could be confirmed or rejected unequivocally: there were indicators for the continuing importance of urban service centres but no peripheral industrialization for the continuing dominance of industrial core regions while undergoing structural changes. It is concluded that there are hardly any signs of convergence between core and peripheral regions.  相似文献   
83.
At the national level, trade-weighted real exchange rates and foreign incomes significantly impact exports. At the subnational level, these variables are generally insignificant in the few studies that include them. We argue that the standard use of national trade weights in the construction of subnational trade-weighted averages of exchange rates and foreign incomes is inappropriate, and we then construct these variables using state-specific trade weights. In our panel data analysis of state-level manufacturing exports, these variables enter significantly and with the expected signs. Also, their out-of-sample forecasting ability is significantly better than that of the national trade-weighted variables.  相似文献   
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During the archaeobotanical investigation of Scythian–Sarmatian period (Early Iron Age), pits with crop processing waste, discovered in the floodplain of Donets River, eastern Ukraine, and charred remains of cereal grains, dominated by broomcorn millet, were recorded. The grains from the pits were radiocarbon dated to the fifth to first century BC. Those pits are distant from any known contemporaneous settlement. The apparent disconnection of these pits from any local settlement suggests that (1) millet was brought from other locations by mobile groups, or (2) millet was cultivated locally by populations whose settlements have left no discernible archaeological trace. The analysis of molecular biomarkers preserved in palaeosols that are stratigraphically connected to the pits revealed high levels of miliacin, a molecule that can be preserved in ancient soils and sediments, and that is consistent with broomcorn millet (Panicum miliaceum). High levels in miliacin in soils stratigraphically connected to the pits are interpreted as the result of a large biomass of P. miliaceum produced at time of soil formation. Our biogeochemical results applied to a palaeosol thus attest to the in situ cultivation of crops dominated by the broomcorn millet during the early Iron Age in the floodplain of Donets River. Biochemical examination of soils and palaeosols can thus provide useful information on past dynamics of land-use by ancient population, especially when settlements or macrobotanical remains are absent.  相似文献   
86.
Observations are presented of a newly deposited snow-push ridge superimposed on a Holocene moraine in Coire an Lochain in the Cairngorm Mountains. The ridge formed when a sliding snow slab was thrust up the proximal slope of the moraine, entraining till gravel and redepositing it on the moraine crest. The process was a late-stage event during the complex wastage of a large snowfield resting on a rock slab, involving basal sliding, avalanching and melting. Snow-push landforms appear to be rare in Scotland. Nevertheless, these observations suggest that fresh material may be added to relict moraine crests in the present-day climate, with implications for exposure-age dating of moraines. However, in this case the addition of debris by snow push to a late Holocene moraine crest does not affect the interpretation of moraine age.  相似文献   
87.
88.
Several attempts have been made recently to apply Darwinian evolutionary theory to the study of culture change and social history. The essential elements in such a theory are that variations occur in a population, and that a process of selective retention operates during their replication and transmission. Location of such variable "units" in the semantic structure of cognition provides the individual psychological basis for an evolutionary theory of history. Selection operates on both the level of cognition and on its "phenotypic" expression in action in relation to individual preferred sources of psychological satisfaction. Social power comprises the principal selective forces within the sociocultural environment. Sociocultural evolution takes place both as a result of the unintended consequences of action and through the struggle of individuals and groups in pursuit of opposing interests. The implications for historiography are methodological in that evolutionary theory of history sharpens the focus of explanatory situational analysis, and interpretive in that it provides a paradigmatic metanarrative for the understanding of historical change.  相似文献   
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The 2000 and 2004 US Presidential elections were closely fought contests, with in the first case victory in the Electoral College being denied to the candidate with the largest share of the popular vote. Disproportionality in the translation of votes into seats (in this case, from popular votes to votes in the Electoral College) is common to contests using a winner-takes-all electoral system. So is bias, whereby that disproportionality does not apply equally to each candidate. Analysis of the bias at those two elections shows that Bush was favoured at the first but not at the second. Identification of the bias components shows that Bush was advantaged by variations in the number of popular votes per Electoral College voter across the states, and also by variation in turnout. In 2000, his popular votes were also more efficiently distributed than Gore's; in 2004 they were less efficiently distributed than Kerry's, largely because of increased turnout – producing larger numbers of surplus votes – in states that were already safe for Bush.  相似文献   
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