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Molding maize: the shaping of a crop diversity landscape in the western highlands of Guatemala 总被引:2,自引:0,他引:2
Today's domesticated plants not only embody past human–nature interactions, but also reflect social history. Human seed exchange, replacement and loss are important forces in shaping crop diversity. This essay explores regional history in relation to the shaping of maize diversity in the western highlands of Guatemala. This is an area of exceptional maize heterogeneity and a peripheral part of the region where maize was domesticated. Maize diversity seems to have developed through geographic isolation in networks of seed exchange that were generally very local in scope. However, recent studies on Mexican maize suggest otherwise. However, few studies have examined crop diversity or seed exchange from a historical perspective. A closer examination of regional history suggests which processes might be important for shaping the present geographical distribution of maize diversity. Seeds were occasionally transported over longer distances. As a consequence, maize diversity is geographically not characterised by sharp differences between farming communities; the main differences are to be found in regional occurrences. This challenges antimodern ideas of closed, local native ecologies. Consequently, the conservation of maize genetic resources is a challenge, but not entirely contradictory with its transforming socio-economic context. 相似文献
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This paper examines the dynamics of the computer hardware industry in Ireland and Scotland in a global context, from its inception in the late 1950s to the present. It provides a detailed account of plant openings and closures in both the system assembly and the component manufacturing segment. It describes the development of the computer hardware industry from mainframe assembly, through minicomputer assembly to microcomputer assembly and the shift of system assembly and component production activity to the Far East and Eastern Europe since the mid-1990s. The developments are analysed in terms of Schoenberger's (1997) model of concentrated deconcentration in the context of time-based-competition. It is shown that the model, with substantial qualification, fits the developments since the 1980s. 相似文献
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Annemarie van Heerikhuizen 《European Legacy》2008,13(4):401-411
This article traces the development of European ideas of peace and unity from the time of Desiderius Erasmus to Immanuel Kant. The argument will be made that these ideas, which were initially strongly determined by Christian religious thinking, gradually changed, and from the seventeenth century onwards were put forward in more political and legal terms. Erasmus's way of reasoning about peace and war was still strongly influenced by his firm orientation on the New Testament and the teachings of Jesus Christ. Emeric Crucé, a French writer, was of the opinion that all human beings in the end had God in common, and so had to live peacefully together. Duc de Sully was one of the first not to argue as a religious man but as a politician: a system of balance of power could bring international stability. According to the English Quaker William Penn and the French Abbé de Saint-Pierre only the acceptance of international rules of justice could produce everlasting peace. Immanuel Kant finally directed attention to the form of government and to the founding of a federation of free republics. So God seems to have disappeared from Europe?…?but with what consequences for today? 相似文献
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This article investigates how the Makuleke community in Limpopo Province achieved iconic status in relation to land reform and community‐based conservation discourses in South Africa and beyond. It argues that the situation may be more complex than it first appears, and the ways in which the Makuleke story has been deployed by NGOs, activists, academics, conservationists, the state and business may be too simplistic. The authors discuss historical representations of the Makuleke ‘tribe’ against the backdrop of their experiences of living in the borderland Pafuri region of the Kruger National Park prior to their forced removal. After investigating the ways in which the chieftaincy, and its relation to communal land, has been strengthened by local mobilizations against threats from the neighbouring Mhinga Tribal Authority, the authors suggest that a central tension in the Makuleke area is the conflict between democratic principles governing the legal entity in control of the land (i.e., the Communal Property Association), and traditionalist patriarchal principles of the Tribal Authority. The article shows how these restitution‐linked processes became implicated in the establishment in 2002 of the Great Limpopo Transfrontier Park. The authors also argue that the image of the Makuleke as a ‘model tribe’ is both a product of changing historical circumstances and a contributor to contemporary discourses on land restitution and conservation. 相似文献
46.
A group of Roman glass objects from the Bocholtz burial in the SW of Limburg (The Netherlands) was found to have been subject to varying degrees of degradation. Many of the 25 colourless glass objects were fragmented to pieces <0.1 cm (“sugared”), whereas the three transparent blue-green glass objects were in near-pristine state. Analyses using SEM, XRF and EDS revealed that the fragmentation was the direct result of the intense leaching of Na2O from the glass structure and its replacement with water. The resulting gel layers with low-Na2O contents and large amounts of water are sensitive to cracking when they dry out. Thin-walled glass appears to be less sensitive to cracking from the resulting stress than thick-walled glass. Local differences in the moisture regime during burial also influence the severity of the glass degradation. Glass with low concentrations of CaO seems to be the most sensitive to this form of degradation. The typical blue-green Roman glass is less sensitive as it generally has considerably higher concentrations of CaO. 相似文献
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