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961.
The European Union anticipates alleviating future energy shortages and fulfilling renewable energy mandates by importing “green” electricity from Africa. Historical precedent and environmental consequences have largely been ignored. This article presents an environmental history of African electricity generation at a continental scale, tracing its parallel developments with colonialism, as well as its pursuit in the independence eras of development assistance and neoliberalism. Initially electricity served European interests. Independent governments' development policies involved electrification primarily for industrial development; in North Africa, universal access was also a priority. Recurrent themes and cycles of environmental constraint, environmental disruption, and displacement of consequences from one ecosystem to another are addressed. Highlighted are inter‐relationships among electricity generation, fuel supplies, ecosystems, and water cycles. Late twentieth century technologies and globalized markets re‐valued African rivers and deserts as potential energy sources. Mega‐engineering projects were rejuvenated or proposed. Rural electrification was labelled uneconomic social welfare unrelated to economic development policies of selling power through national, regional, continental and intercontinental interconnections. Historical analysis suggests new areas of research for sustainable development and alternatives to declensionist narratives. Decentralized, small‐scale plants offer models of electricity supply for industrial and domestic needs, while investment in rural electrification produced measureable economic benefit at national levels. Will the EU renewable energy mandate simply displace Europe's environmental problems to Africa? Can Africa afford another water‐intensive export commodity? Will the New African Century follow well‐established patterns of exploitation, or take new, sustainable directions?  相似文献   
962.
The potential use of existing radiometric data sets, previously collected for prospecting purposes, has very rarely been used as a variable predictor in wildlife habitat modelling. The utility of radiometric data for predicting vegetation community patterns and wildlife habitat was investigated in the Australian arid zone using the Burt Plain bioregion as a case study. Using spatial datasets and a Species Distribution Modelling Toolkit, arid zone vertebrate species were modelled with Generalised Linear Modelling (GLM) regression modelling techniques. These models were used to predict the probability of occurrence of a species at any given location, defined in terms of its environmental attributes. A statistical correlation between the radioactive elements uranium, thorium and potassium, and terrain aspect was found. No statistical correlations were established between the radioactive elements and vegetation patterns; although we suspect these exist at finer scales of mapping. Radiometric data were identified as explanatory variables in the habitat models of all of the 32 vertebrate species examined, and used as illustration in the development of probabilistic spatial predictions of three species (Red Kangaroo, Macropus rufus; Lesser Hairy‐footed Dunnart, Sminthopsis youngsoni; and Rabbit, Oryctolagus cuniculus) in the bioregion. Our analyses suggest that radiometric data sets involving the radioactive elements: (uranium, thorium, and potassium), and vegetation could be used as predictors of biodiversity patterns at the bioregional and landscape level. This is an important finding given the challenges posed in undertaking broad‐scale biological surveys in the arid zone of Australia.  相似文献   
963.
A comparison of Giuseppe Bagetti's landscape sketches, watercolours, oil paintings and engravings with contemporary maps and the existing landscape reveals that in the creation of Bagetti's landscapes, narrative played a role that differed in cartographic and artistic representations. The comparison also demonstrates that his images were powerful constructions that were more successful in reflecting a narrative of glorious conquest than was possible through cartography. This paper offers a critical examination of Bagetti's representations of Napoleon's northern Italian campaign, which he sketched and painted between 1802 and 1809. Bagetti's paintings were neither pacifist nor an expression of Piedmontese patriotism but instead were inspired by, and constructed according to, a narrative about the conquest that reflected the views of the French authorities. The narrative found expression in formal written instructions from the central cartographical office in the Dépôt de la guerre, Paris, in verbal and written instructions from Bagetti's immediate superior, Jean François Martinel, and in letters personally addressed to Bagetti from the officer commanding the Dépôt. It is clear from a careful reading of the correspondence and from a comparison of Bagetti's paintings with both the present landscape and maps made at the time that Bagetti's disputes with his supervisors revolved around protecting his artistic integrity and reputation rather than resisting the authority of a foreign regime.  相似文献   
964.
The article discusses health policies towards school children in Norway from 1900 until the Second World War. It is concerned with dominant definitions of health threats against children and the variables used in defining the groups conceived as most vulnerable to poor health. A distinct change took place in the period. Whereas in the early 1900s poor and working‐class children in urban surroundings were considered to be under severe threats, in the 1920s a less specific category of ‘children’ were conceived as threatened. Eventually rural children were singled out as the important target group for health measures. The shifts had medical as well as political motivations. Another prominent feature in the period was that poverty took on a new meaning in the dominant medical discourse on children: from having been conceived as a material reality impinging upon health, it came to be considered mainly a cultural problem. Especially medical officers within the social democratic camp contested this argument although they did not rule out education and cultural transformation as a means to promote children's health. Despite the conceptual shift, however, social benefits and equal access to health services – measures that lay at the heart of the post‐war welfare state – remained in the 1930s an essential part of promoting children's health.  相似文献   
965.
This article addresses the influence of dominant and traditional ways of grasping the reality in social and economic processes of change. Our point of departure is how the perception of crisis in Odda, a small industrial community in Norway, influences the course of the process of change. The analysis focuses on a heated debate over the exploitation of a large site in the centre of Odda, left after the closure of the key factory. Rather than the economic and social consequences of the closure, the main challenge that arose from the crisis was related to the emergence of ambiguity in the local conceptual framework. Coming to terms with the situation stimulated various attempts to rearticulate the discourse of local development, with the result that industrial and culture‐based perspectives on development came into conflict. The economic crisis became a crisis of definition. In Odda, the industrial discourse finally domesticated the competing cultural discourse, ending years of conflict and inaction. In its explicit focus on the importance of local struggles and the way discourse structures such processes this story about recent developments in Odda complements literature on post‐industrial development.  相似文献   
966.
As social communities, regions are built through discourses that convey images of what the region is. Regions are built for a variety of reasons, including political and economic ones. This implies that changing economic circumstances have the potential to change the discourses on regional identities. Petroleum discoveries represent such a potential change in the economic circumstances of a region. This study of an emerging petroleum region in the north of Norway shows that a regional identity discourse is used to claim ownership over the petroleum resources in the Barents Sea in order to justify the need for a production plan that maximizes regional economic benefits. In this way, the discovery of petroleum represents an opportunity to reinforce regional identities around a set of common interests. However, “the region” is vaguely defined in this discourse, being used in reference to two different scales: Finnmark and Northern Norway.  相似文献   
967.
X‐ray diffraction or scattering analysis provides a powerful non‐destructive technique capable of providing important information about the state of archaeological samples in the nanometer length scale. Small‐angle diffraction facilities are usually found at synchrotron sources, although the potential of a laboratory source is also described. Specific examples of analysis using X‐ray diffraction of historic parchment, archaeological bone, a Central Mexico style pictograph and microdiffraction of calcified tissues are used to show the scope and versatility of the technique. Diffraction data is capable of giving fundamental structural information as well as quantifying the remodelling of structures influenced by environmental factors.  相似文献   
968.
Cluster analysis is the most widely used multivariate technique in archaeometry, with the majority of applications being exploratory in nature. Model‐based methods of clustering have their advocates, but have seen little application to archaeometric data. The paper investigates two such methods. They have potential advantages over exploratory techniques, if successful. Mixture maximum‐likelihood worked well using low‐dimensional lead isotope data, but had problems coping with higher‐dimensional ceramic compositional data. For our most challenging example, classification maximum‐likelihood performed comparably with more standard methods, but we find no evidence to suggest that it should supplant these.  相似文献   
969.
P. Mirti  P. Davit 《Archaeometry》2001,43(1):19-33
Sherds of Campanian pottery were studied by SEM‐EDX. SEM images show that slips of Campana C are scarcely sintered and are thicker than the well vitrified coatings of Campana A and B and imitations of Campana B. Slips of products with a grey slip on a grey body are very thin and well vitrified. EDX analyses indicate that slips are richer in aluminium and iron, and poorer in silicon and calcium, with respect to the bodies. Higher potassium is also found in all of the coatings except those of Campana A. Here relatively high sodium makes the total alkalis comparable with those of the other products, except Campana C, where it is somewhat lower. Measurement of thermal expansion and X‐ray powder diffractograms suggest that firing temperatures were mostly in excess of 900°C, but some samples of Campana C seem to have been fired below 800°C.  相似文献   
970.
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