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21.
Four decades have passed since Harlan and Stemler (1976) proposed the eastern Sahelian zone as the most likely center of Sorghum bicolor domestication. Recently, new data on seed impressions on Butana Group pottery, from the fourth millennium BC in the southern Atbai region of the far eastern Sahelian Belt in Africa, show evidence for cultivation activities of sorghum displaying some domestication traits. Pennisetum glaucum may have been undergoing domestication shortly thereafter in the western Sahel, as finds of fully domesticated pearl millet are present in southeastern Mali by the second half of the third millennium BC, and present in eastern Sudan by the early second millennium BC. The dispersal of the latter to India took less than 1000 years according to present data. Here, we review the middle Holocene Sudanese archaeological data for the first time, to situate the origins and spread of these two native summer rainfall cereals in what is proposed to be their eastern Sahelian Sudan gateway to the Red Sea and the Indian Ocean trade.  相似文献   
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First visited by westerners in the mid-nineteenth century, Saharan rock art has since received a great deal of attention. The richness and diversity of this region is recognised by the inclusion on the UNESCO World Heritage list of three properties: Tassili-n-Ajjer in Algeria, Tadrart Acacus in Libya, and Ennedi in Chad. The situation in many North African countries now makes this vast region very difficult to access: safety in the field is not guaranteed and few research funds are available. Today, a new generation of African and foreign scientists has no access to rock art sites in the north of the continent and the lack of fieldwork may entail a lack of safeguard and awareness. The growth of digital technologies over the last 15 years has revolutionised methods for recording rock art sites. Digital technologies are also used to mitigate the gap between artworks and accessibility in those countries where turmoil and social instability make fieldwork impossible. However, much of the documentation and most digital recordings of artworks currently available on the Internet lack an archaeological context. Equally, many of these websites barely mention methodological and theoretical aspects. It is also difficult to understand the extent of awareness among local communities in remote areas—sometimes suffering a digital and linguistic divide—and if (and how) they are genuinely able to exploit these digital resources. Here, I collate some examples from different parts of the Sahara illustrating that the recording, management and dissemination of rock art still present highs and lows. I argue that we should share theories and methods within the digital scientific community, with a view to adopting a shared nomenclature and a public thesaurus, making our cataloguing criteria explicit and, finally, developing an ethical code of conduct involving local communities.  相似文献   
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In this work, we apply a systemic approach to the analysis of a particular geographic territory, the industrial district. We are particularly interested in analysing the interaction between the productive-technological environment and the scientific environment by an examination of research contracts and patents. Our analysis shows that R&D activity in the Spanish ceramic tile District Innovation System was mainly conducted by suppliers. Final producers’ innovation efforts were related to non-technological aspects and differentiation.  相似文献   
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The defining element of island regions is their isolation, the separation of the islands from the mainland; there is an inherent notion of natural border. This condition has preserved ecosystems and protected against outside threats, stimulating ‘coevolution’ between man and the environment, a fundamental ingredient of sustainability. But insularity also means the evident added costs of access to markets which, together with territorial limits and the scarcity of basic resources, especially on small islands, hinders their socioeconomic development. These costs are even greater in the case of outlying islands, which suffer from a ‘double insularity’ in the form of both external and internal borders. For this reason, it is common for governments to establish various forms of support, from tax exemptions to the creation of permanent aid funds, like those implemented by the European Union for the outermost regions. This article discusses these aspects in the case of the Canary Islands, an example of a European outermost island region. The findings show that the support measures have not always been favourable for all the islands.  相似文献   
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The aim of this paper was to develop a social sustainability tool to clarify what social sustainability means in land use planning processes. The tool was developed through a robust research process covering a large amount of scientific literature and built environment sustainability assessment tools. To assess how the developed tool works in practice, we used it as a coding system for the assessment of social sustainability in a case study from Finland. The case study includes the master planning process of a medium-sized city and the legal framework guiding it. The theoretical contribution of the paper lies in creating a holistic tool for the assessment of social sustainability in planning processes. This study also provides a strong practical contribution, as it goes beyond theoretical definitions to the pragmatic level by providing exemplary measures to be used in designing and implementing processes. Therefore, this paper is a valuable source for those stakeholders (for example planners, developers and policymakers), who struggle with the issue of the successful implementation of social sustainability practices, and it will help them to benchmark their processes against the themes found in the tool.  相似文献   
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This paper introduces a special themed section that arose from an International Conference on Feminist Geographies and Intersectionality: Places, Identities and Knowledges, held in 2016 at the Universitat Autònoma de Barcelona. Six scholars of Canada, France, Greece, New Zealand, United Kingdom and United States seek to deal in five short papers with the intersectional dynamics of power structures and the central role of place within them. Here we situate the developments of intersectionality in feminist geographies in relation to the role of place and space in constituting intersectional relations, the relevance of context for the development of intersectionality and the use of different methodologies for research on it.  相似文献   
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This article examines a group of photographs bearing a strong violent content that were published in print and digital media as part of the coverage of the ‘war against drugs’ in Mexico: an armed conflict initiated by the central government in December 2006. This military action was the first step in a process of militarization affecting several states, in which an attempt was made to dismantle territorial pacts between cartels, to control the illegal traffic in drugs and, supposedly, to put an end to the use and production of drugs among the population. This war gave rise to one of the bloodiest episodes of contemporary Mexico in which drug cartels reproduced and invented new methods of torture that were used not only upon the gunmen of rival cartels but also on a significant number of civilians. In the coverage of these events, not all photojournalists reacted to this upsurge in violence in a ‘sensationalist’ manner; several set out to produce images from unusual points of view. In particular, I shall analyze how certain images represent violence in a tense relationship with artistic iconography, upsetting parameters of horror and beauty in the public sphere.  相似文献   
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