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Roads have manifold social and environmental impacts, including regional development, social conflicts and habitat fragmentation. ‘Road ecology’ has emerged as an approach to evaluate the various ecological and hydrological impacts of roads. This article aims to complement road ecology by examining the socio‐spatial processes of road building itself. Focusing on the Brazilian Amazon, a heavily‐studied context due to forest fragmentation by roads, the authors consider non‐state social actors who build ‘unofficial roads’ for the purpose of gaining access to natural resources to support livelihoods and community development. They examine four case studies of roads with distinct histories in order to explain the socio‐spatial processes behind road building in terms of profit maximization, land tenure claims, co‐operative and conflictive political ecologies, and constraints as well as opportunities afforded by the biophysical environment. The study cases illustrate the need for a multi‐pronged theoretical approach to understanding road building, and call for more attention to the role of non‐state actors in road construction.  相似文献   
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This article aims at assessing the role of related variety, that is, the relatedness of knowledge bases used by different sectors within a region, as a major driver of clusters’ development. Some recent theoretical papers underline the role of clusters as ‘knowledge platforms’ organizing the recombination of technologies in overlapping industries, following the seminal definition of clusters by Porter as ‘geographic concentrations of linked industries’. In order to investigate the role of related variety in cluster dynamics, we analyse the patterns of development of clusters specializing in photonics in Europe. Photonics constitutes a new and rapidly evolving set of technologies with a high expected degree of technological recombination. However, due to inadequate traditional sectoral classifications, we propose an original method to delineate the perimeter of photonics in patent databases. A two-step algorithm is then used to identify systematically photonic clusters in Western Europe at the local level. In the last part of the paper, a typology of technological trajectories of clusters over the last decades is developed and then correlated with a set of quantitative measures of technological relatedness. The results highly confirm the role of related variety as a major driver of success, particularly for the biggest European clusters.  相似文献   
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European territorial policies increasingly refer to broad goals such as sustainability, well-being and cohesion. For their operationalization as political goals, there is a need to create indicators. But how can an indicator be meaningful in relation to a complex concept that is not well defined? If the creation of an indicator is primarily aimed at quantifying a concept and making it more operational, in the case of a contested concept (such as territorial cohesion), the process of building indicators also helps stabilize it, allowing a potential decontestation. A participatory constructivist approach – as used by the ESPON project Indicators for Territorial Cohesion (INTERCO) – is considered to be the most suitable for building indicators of contested concepts. While ensuring computability of the indicators, it allows more flexibility and reconciles the different meanings of the concept in order to stabilize it. Ultimately, the validity of indicators of contested concepts lies in pragmatic criteria: usability, usefulness and use.  相似文献   
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This paper explores the materiality of social power relationally through study of social interactions with artifacts. Specifically, it is argued that acquisition of an artifact instantiates social power by imposing interactions on groups taking part in that artifact's life-history activities. We introduce the “performance-preference matrix,” an analytic tool for systematically studying the effects of such acquisition events on activity groups. The use of the performance-preference matrix is illustrated through an example: the acquisition of electric-arc lights for lighthouses in the 19th century. Suggestions are offered for analyzing culture-contact situations and for handling singularized artifacts such as heirlooms and monuments.
William H. WalkerEmail:
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Pronghorn (Antilocapra americana) fetal remains are sometimes recovered from archaeological contexts. Pronghorn have consistent reproductive schedules so their remains may provide information on seasonality of site occupation and number of mortality events. To investigate the reliability of fetal remains for seasonality and mortality event assessment, bone size and tooth eruption were measured in a sample of modern fetal pronghorn remains with known mortality dates. Results indicate a strong correlation between bone size and mortality date, but no significant correlation between tooth eruption level and mortality date. Fetal bone size was used to estimate a late April or early May mortality date at both the Oyster Ridge (48UT35) and Trappers Point (48SU1006) archaeological sites. The number of mortality events at Trappers Point was also investigated. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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Field schools are a rite of passage for archaeologists, the first experience of what for many is the defining activity of the discipline: fieldwork. While teaching competence in practical techniques is the minimum goal of any field school, this technical training must be situated within the broader goals that drive the fieldwork. The University of Denver Archaeological Field School provides the fieldwork for the Colorado Coal Field War Archaeological Project. This project is an experiment in archaeology as political action in the present. It explores the possibility of an emancipatory archaeology through engagement with contemporary audiences and struggles. In this paper we discuss some of the ways we try to link technical training with the admittedly unusual theoretical and political goals of the project, teaching not only skills but an awareness of the responsibilities these skills should bring.  相似文献   
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