987 resultados para ARACUAI-WEST CONGO OROGEN


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This book provides a critical investigation into the discursive processes through which the North Atlantic Treaty Organisation (NATO)reproduced a geopolitical order after the end of the Cold War and the demise of its constitutive enemy, the Soviet Union.

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In recent years, policy mechanisms to support a formalized artisanal and small-scale mining (ASM) sector in sub-Saharan Africa have gained increasing currency. Proponents of formalization argue that most social and environmental problems associated with the sector stem from the fact that ASM is predominantly unregulated and operates outside the legal sphere. This paper critically examines recent efforts to formalize artisanal and small-scale mining inWest Africa, drawing upon recent fieldwork carried out in Sierra Leone, Ghana and Mali. In exploring the sector’s livelihood dimensions, the analysis suggests that bringing unregulated, informal mining activities into the legal domain remains a considerable challenge. The paper concludes by confirming the urgent need to refocus formalization strategies on the main livelihood challenges and constraints of small-scale miners themselves, if poverty is to be alleviated and more benefits are to accrue to depressed communities in mineral-rich regions.

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What were the cultural politics of classics in British colonies? Did classical education operate as a sign of oppression, or as a tool for forging an anti-colonial politics? Why did Europeans bring the classics to West Africa, and how did they manage the developing dynamic when West Africans laid independent claim to the classical heritage? This ground-breaking study examines the ways in which European colonisers and West African nationalists clashed, or collaborated, over the uses of Latin, Greek and the classics.

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This paper introduces a new English Heritage (Aggregates Levy Sustainability Fund) project The Palaeolithic Rivers of South-West Britain (project no. 3847), and summarises the results of a first phase resource assessment. The goal of this ongoing project is to develop a new synthesis of the Lower and Middle Palaeolithic occupation of the south-west region, focusing upon river terrace-based archaeology and its implications for hominin landscape use. The resource assessment has reached two preliminary conclusions. Firstly that the region’s earliest Palaeolithic archaeological record is significantly richer than previously believed, and secondly that although find locations have been added in several areas which previously had very few or no finds (e.g.West Cornwall) the overall bias of finds to the south coast is maintained. The project has also revealed that the river terrace resource of South-West England offers potential for geochronological dating, landscape reconstruction, and improved contextualisation of the archaeological material. Some outreach components of the project are also summarised.

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Using the record of 30 flank eruptions over the last 110 years at Nyamuragira, we have tested the relationship between the eruption dynamics and the local stress field. There are two groups of eruptions based on their duration (< 80days >) that are also clustered in space and time. We find that the eruptions fed by dykes parallel to the East African Rift Valley have longer durations (and larger volumes) than those eruptions fed by dykes with other orientations. This is compatible with a model for compressible magma transported through an elastic-walled dyke in a differential stress field from an over-pressured reservoir (Woods et al., 2006). The observed pattern of eruptive fissures is consistent with a local stress field modified by a northwest-trending, right lateral slip fault that is part of the northern transfer zone of the Kivu Basin rift segment. We have also re-tested with new data the stochastic eruption models for Nyamuragira of Burt et al. (1994). The time-predictable, pressure-threshold model remains the best fit and is consistent with the typically observed declining rate of sulphur dioxide emission during the first few days of eruption with lava emission from a depressurising, closed, crustal reservoir. The 2.4-fold increase in long-term eruption rate that occurred after 1977 is confirmed in the new analysis. Since that change, the record has been dominated by short-duration eruptions fed by dykes perpendicular to the Rift. We suggest that the intrusion of a major dyke during the 1977 volcano-tectonic event at neighbouring Nyiragongo volcano inhibited subsequent dyke formation on the southern flanks of Nyamuragira and this may also have resulted in more dykes reaching the surface elsewhere. Thus that sudden change in output was a result of a changed stress field that forced more of the deep magma supply to the surface. Another volcano-tectonic event in 2002 may also have changed the magma output rate at Nyamuragira.

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Within a changing climate, Mediterranean ‘Garrigue’ xerophytes are increasingly recommended as suitable urban landscape plants in north-west Europe, based on their capacity to tolerate high temperature and reduced water availability during summer. Such species, however, have a poor reputation for tolerating waterlogged soils; paradoxically a phenomenon that may also increase in north-west Europe due to predictions for both higher volumes of winter precipitation, and short, but intensive periods of summer rainfall. This study investigated flooding tolerance in four landscape ‘Garrigue’ species, Stachys byzantina, Cistus × hybridus, Lavandula angustifolia and Salvia officinalis. Despite evolving in a dry habitat, the four species tested proved remarkably resilient to flooding. All species survived 17 days flooding in winter, with Stachys and Lavandula also surviving equivalent flooding duration during summer. Photosynthesis and biomass production, however, were strongly inhibited by flooding although the most tolerant species, Stachys quickly restored its photosynthetic capacity on termination of flooding. Overall, survival rates were comparable to previous studies on other terrestrial (including wetland) species. Subsequent experiments using Salvia (a species we identified as ‘intermediate’ in tolerance) clearly demonstrated adaptations to waterlogging, e.g. acclimation against anoxia when pre-treated with hypoxia. Despite anecdotal information to the contrary, we found no evidence to suggest that these xerophytic species are particularly intolerant of waterlogging. Other climatic and biotic factors may restrict the viability and distribution of these species within the urban conurbations of north-west Europe, but we believe increased incidence of flooding per se should not preclude their consideration.

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This paper details the results of recent reanalysis of the animal remains from the 1960s excavations at Fishbourne Roman Palace, West Sussex. It argues that specimens originally identified as belonging to the great bustard are, in fact, misidentified remains of common crane. This discovery has important connotations. First, these findings need to be reported so that the avian archaeological record can be updated to avoid future syntheses of Romano-British faunal remains incorrectly including great bustard. Secondly, interpretations of the zooarchaeological remains at Fishbourne Palace will alter, due to the differing ecological histories of bustards and cranes.

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The countries in West Africa (WA) are pushing for socio-economic development. The construction sector has an important part to play in helping to realise these aspirations. This necessitates an increased emphasis on research in the built environment, as a key contributor to developing capacity, knowledge and technologies for the sector. The West Africa Built Environment Research (WABER) conference was initiated in 2008. The objective was to: help young built environment researchers in West Africa (WA) to develop their research work and skills through constructive face-to-face interaction with their peers and experienced international academics; supply a platform for interaction among more senior academics and an outlet for disseminating their research work; and to serve as a vehicle for developing the built environment field in Africa. Three conferences have so far been organised, 2009 - 2011, bringing together ~300 academics, researchers and practitioners from the WA region. This paper draws on content analysis of the 189 papers in the proceedings of three conferences: 2009 (25); 2010 (57) and 2011 (107). These papers provide a window into current research priorities and trends and, thus, offer an opportunity to understand the kinds of research work undertaken by built environment researchers in West Africa. The aim is to illuminate the main research themes and methods that are currently pursued and the limitations thereof. The findings lay bare some of the many challenges that are faced by academics in WA and provide suggestions for alternative directions for future research and development work with indications of a potential research agenda.