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101.
In the present study the author examines the migratory practices of movement between France and Portugal of young French of Portuguese ancestry, as well as of young Portuguese living in France. The study of these practices from an ethnological point of view sheds light on the interaction of material resources and the multifaceted symbolic resources associated with them. Besides the economic and political dimension in which these practices are grounded, the identity — forming process of which they are a part raises a number of questions — especially in the context of the European Union. The author shows how, by using elements drawn from the family migratory history, natural history and Portuguese culture, the descendents of Europeans who migrated for economic reasons are now trying to go beyond the dilemma of an identity posed by their «double culture», as well as the social and cultural constraints imposed on them by their elders.  相似文献   
102.
Fire safety is an important issue of building safety, especially when the building’s fire load contents enhance the risks of fire deflagration. When existing timber structures are involved, the most usual way to improve its reaction to fire is to treat wood with fire retardants. This study focuses on the surface protection of existing timber roof structures against fire, through the use of fire retardant (FR) treatments applied on site. An experimental investigation was carried out to study the effect of FR treatments on timber reaction to fire, with a special emphasis on timber members with biological deterioration and previously treated with preservative products. The behaviour and effectiveness of intumescent and non-intumescent treatments was also investigated. The study showed that the application of FR treatments improved the reaction to fire of timber, even in the presence of previous preservative treatments. However, the choice of the specific FR treatment should take into account the substrate conditions. In addition, test results suggest that protection systems involving multi layers (intumescent and non-intumescent) with different functioning modes each are likely to have a good global performance on the protection of timber elements against fire.  相似文献   
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This paper analyses U.S.-Brazilian relations during the elaboration of João Goulart’s Three-Year Plan in late 1962, which sought to tackle Brazil’s severe economic imbalances without compromising growth and through the implementation of distributive reforms. Although the plan followed the principles of John F. Kennedy’s Alliance for Progress, Washington did not offer adequate assistance because of Goulart’s threats to increase links with the Soviet bloc. The United States hardened its position, seeking to change the orientation of the Brazilian government. This led to the abandonment of the Three-Year Plan, and contributed to social and political destabilisation that resulted in Brazil’s March 1964 military coup.  相似文献   
105.
The main goal of this paper is to review the earliest archaeological evidence for the presence of humans in Fuego-Patagonia. The paleoenvironmental and paleoclimatic framework is briefly introduced, followed by a discussion of its relevance to understanding the exploration and colonization of Fuego-Patagonia. Technological and faunal evidence from a number of sites from the southern extreme older than 10,000 B.P. is analyzed. This leads to the conclusion that an early entry, at least 12,000 years old, appears best to accommodate the available chronological evidence. On the other hand, data from the Northern fringes of Patagonia clearly suggest an earlier human colonization.  相似文献   
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At most Pleistocene archaeological sites it is difficult to observe structured complex spatial behaviour. This common phenomenon could be a taphonomic issue. Problems in the preservation of the original spatial intra-site distribution could be related to hominid–carnivore alternation in the use of space. In the present paper we analyse the results of our experimentation with large extant carnivores (bears, wolves, hyenas and lions) and propose these animals acted as hearth and hearth-related assemblage modifiers. In this sense, the role of carnivores in the modification of these elements can cause problems in the interpretation and visibility of modern and complex behaviour in the conception of space in the archaeological record.  相似文献   
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A collection of 54 bronze artefacts recovered from the inland settlement of Castro dos Ratinhos (Portugal) and belonging mainly to the 9th–8th centuries BC, was studied by the use of non-invasive and micro analytical techniques. EDXRF, Micro-EDXRF, SEM-EDS and Optical Microscopy were used to determine the alloy composition and to identify the different thermo mechanical operations applied in the production of the artefacts. Results show that the collection is entirely composed of good quality binary bronzes (with an average tin content of 10.1 ± 2.5%). Alloys with higher tin contents were kept in as-cast condition and used in the making of ornaments, while tools were often finished with forging and annealing operations. Despite the existence of some Orientalising features in the Castro dos Ratinhos, e.g. rectangular habitat structures, wheel-turned ware and amphorae, the exclusive use of binary alloys with a narrow range of tin content seems to be associated with an indigenous metallurgical tradition inherited from the Late Bronze Age. This may indicate that the Phoenician interaction within the inland indigenous communities was a slow and selective process, probably dependant on the social-economic and cultural development of local communities.  相似文献   
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