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Since 2005 we have been utilizing accelerator mass spectrometry (AMS) 14C dating in research on calcium oxalate crusts associated with open air rock art of the Iberian Peninsula. In this paper we present two dates linked with three eye-idol pictographs at Abrigo de los Oculados (Henarejos, Cuenca, Spain). Radiocarbon ages for these motifs agree with the expected iconography-based archaeological chronology. Such oxalate dates could provide an independent basis for evaluating chronological theories for post-Palaeolithic sites, designated in the UNESCO World Heritage List as Rock Art of the Mediterranean Basin on the Iberian Peninsula.  相似文献   
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This article examines the realignments of the developmentalist discourse and strategy of the Brazilian military for the Amazon during the civilian government of the ‘New Republic’ (1985–90). It focuses on a case study, i.e. the official expropriation of the lands of the Yanomami Indians in the states of Roraima and Amazonas along the Brazil/Venezueta border. The analysis brings to light how, during this period, the military aimed at neutralizing both the pressure of environmental NGOs on Brazil's international creditors and the emergent democratization of decisions on land use in Amazônia. It shows how such attempts involved manipulating environmental legislation and ecological rhetoric in order to perpetuate military hegemony over the development of Amazônia to the benefit of mining interests. Finally, the paper traces the roots of these man?uvres to a geopolitical and economical model for Amazonian integration still inspired by the national security doctrine drawn up in the 1950s and 1960s by the Escola Superior de Guerra.  相似文献   
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This article traces the responses of Afrikaners to the symbolism and political purposes of the 1947 royal visit to Southern Africa, the first post-war royal tour and the first visit of a reigning sovereign to the Union of South Africa. Taking place in the aftermath of a war that had caused bitter political divisions within Afrikaner ranks and stimulated radical populist nationalism, a royal tour intended to express the crown's gratitude for South Africa's participation in that war was bound to be contentious. Drawing on press accounts, biographies, autobiographies and archival sources, this article argues that the layered reactions of Afrikaners demonstrate that, even on the eve of the National Party's electoral victory on a republican and apartheid platform, attitudes towards monarchy and the British connection were more fluid and ambiguous than either contemporary propaganda or recent accounts have allowed. The diverse meanings attributed to this iconic royal tour reveal a process of intense contestation and reflection about South Africa's place in an empire that was in the throes of post-war redefinition and transformation, and confirm recent characterisations of the 1940s as one of manifold possibilities such that outcomes, like the electoral victory of the National Party in the following year, was far from predetermined.  相似文献   
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The phytolith record from archaeological strata is a powerful tool for reconstructing aspects of past human behaviour and ecology. Considerable insights into the problems and potentials of this record can be obtained by studying phytoliths in modern plants. We prepared a phytolith reference collection of modern plants mostly from northern Greece that includes quantitative information on phytolith concentrations (number of phytoliths per gram dry organic material) and morphological assemblages. Here we analyse this reference collection with the aim of evaluating the strengths and weaknesses of the archaeological phytolith record. The reference collection comprises 62 different plant taxa. Of them, 28 are trees, 1 conifer, 10 shrubs and 1 herb, 3 domesticated annual legumes and 19 monocotyledons. We demonstrate quantitatively the extent to which woody species, legumes and fruits of dicots contribute only small amounts of phytoliths to the sediments per unit tissue dry weight, while leaves of trees and shrubs produce significant amounts of phytoliths and grasses are prolific phytolith producers. We compare the data of this reference collection with a similar reference collection from another Mediterranean ecosystem (Israel). The comparison indicates that some aspects of phytolith production are probably genetically controlled, whereas others are environmentally controlled. We note that despite the fact that woody species produce few phytoliths per gram of tissue, their record can be most informative when taking into account other properties of the sediments. We also note that jigsaw puzzle-shaped phytoliths normally form in plants that grow in humid conditions, but may form in arid environments when the plants are irrigated. This study clearly shows the extent to which some plants can be under-represented and others over-represented in the phytolith record. Knowing the extent of this bias can greatly improve our interpretation of the phytolith record.  相似文献   
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This article uses focus group data to explore the connection between scientific uncertainty about environmental risks and the emergence of distrust among local populations, regulators, and technical experts affected by those risks. With data from a nationwide study of issues associated with the cleanup of U.S. nuclear weapons facilities, the article uses "dialogue theory" and focus group data from three locations to identify the sources of miscommunication and distrust among these actors. The authors conclude that, despite problems with perception and communication among these groups, enough common ground exists to be optimistic about expanding participation for all affected groups in the policymaking process. In fact, expanded participation should diminish the distrust developed from previous regulatory regimes.  相似文献   
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I present in this paper a non-reductionist framework of eight nested modes of evolution that have successively emerged to organize the reproduction of all organisms, from the blue-green algae to our societies. The processes of biological, “Darwinian” evolution are those of drift during reproduction, and of selection. The key unit of evolutionary time is the generation, and its locus is the organisms' life-cycle setup. Different life-cycle setups support different mechanisms of reproduction, and therefore different modes of evolution. By tracing the different life-cycle setups attested throughout life's history, we can characterize the successive modes of evolution with which they are associated as follows: basic; reptilian; archaic mammalian; progressive mammalian; sociocultural; extrasomatically enhanced sociocultural; tinkering; and finally parabiological. These successively emerging modes govern a progressively reduced number of life-forms. The first four modes are “Darwinian” in the strict sense. The fifth, or sociocultural mode, which governs whales and elephants' societies in addition to hominoids, is already not “Darwinian” in the traditional sense. The last three modes have emerged with the genus homo, through the progressive extension of its life-cycle setups. The present framework is to be used heuristically, as a prism with which to separate the evolutionary spectrum of the constituent elements of human behavior. An example of such a behavioral evolutionary spectrum is presented in conclusion, and used to compare the present framework with those recently proposed by Maynard Smith and Szathmáry and by Foley.  相似文献   
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