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31.
We analyse the isotopic values (δ13C, δ15N) of the diet of pre-Columbian horticulturalist populations from tropical and subtropical areas of southeastern South America, belonging to the Guarani and Taquara archaeological units. The data indicate different trends in each one (T?=?4.21; P?=?0.0004), showing a mixed diet with maize consumption in the Guarani samples (δ13Cco?=??15.5?±?1.8‰; δ13Cap ?10.4?±?0.8‰) and a depleted one in the Taquara ones (δ13Cco ?18.2?±?1.7‰; δ13Cap ?11.9?±?0.9‰), with a significant internal dispersion in both populations. The first population has higher nitrogen values (δ15N 11.1?±?0.6‰) compared to the Taquara samples (δ15N 9.3?±?1‰), suggesting a more carnivorous diet. The recognition of these pre-Columbian mixed diets involves the identification of maize cultivation on the Atlantic side of the southernmost area of South America (Parana Delta, 34° SL). Through the analysis of δ18O we have identified two isotopic ecozones, the first along the Paraná River Valley, with an average value of δ18O ?3.7?±?0.5‰ (CV?=?13.5%; CI?=??3.83 / ?3.16), and the second one, located in the Planalto of southern Brazil (Araucaria Forest), with a mean value of δ18O ?1.5?±?0.3‰ (CV?=?16.5%; CI?=??1.69 / ?1.29). The isotopic data (δ13C, δ15N and δ18O) suggest human movements between these two ecozones.  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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There has been noticeable development in the protection of linear infrastructure by UNESCO, whether on its cultural, technological or historical merits. However, with the exception of other means of transport incorporated within the field of industrial archaeology or recognised by the CIIC under the category of cultural routes, little or no consideration has been given to roads built from the mid-eighteenth century to the early part of the twentieth century. In view of this situation, this paper has the following aims. Firstly, to define the concept of ‘modern road’ and provide a brief analysis of the historical development and current situation of the same. Secondly, to assess the main contributions made to date regarding the heritage dimension of modern roads. Thirdly, to reconstruct the process of defining linear cultural landscapes, historic transportation corridors, cultural routes and heritage canals, railways and roads, in accordance with the considerations raised by ICOMOS and UNESCO. Finally, to contribute to the debate on the definition, characterisation and assessment of modern roads as world heritage assets, both intrinsically and in relation to established heritage categories.  相似文献   
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ABSTRACT

The concept of topoiesis of textual space addresses an analysis of the spatial elements that tend to provide a meaning to the literary text. Based on textual semiotics where there is an organized relational system of meanings, in this article we propose that it is possible to determine the function of space as a meaning issue from three different literary text instances (event or motive; character; and object). This distinction will permit a deeper interpretation of the sense of space in the literary text.  相似文献   
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The high Andes of western South America feature extreme ecological conditions that impose important physiological constraints on humans including high-elevation hypoxia and cold stress. This leads to questions regarding how these environments were colonized by the first waves of humans that reached them during the late Pleistocene. Based on previous research, and aided by human behavioral ecology principles, we assess hunter-gatherer behavioral strategies in the Andean highlands during the late Pleistocene and early Holocene. Specifically, we formulate three mobility strategies and their archaeological expectations and test these using technological and subsistence evidence from the six earliest well-dated highland sites in northern Chile. Our results suggest that all of the studied sites were temporarily occupied for hunting, processing animals, and toolkit maintenance. The sites also exhibit shared technological features within a curatorial strategy albeit with different occupation intensities. From this evidence, we infer that the initial occupations of the highlands were logistical and probably facilitated by increased local resource availability during a period of environmental amelioration.  相似文献   
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UNDERSTANDING RELIGIOUS CHANGE between the collapse of the Roman Empire and the Reformation forms one of the cornerstones of medieval archaeology, but has been riven by period, denominational, and geographical divisions. This paper lays the groundwork for a fundamental rethink of archaeological approaches to medieval religions, by adopting an holistic framework that places Christian, pagan, Islamic and Jewish case studies of religious transformation in a long-term, cross-cultural perspective. Focused around the analytical themes of ‘hybridity and resilience’ and ‘tempo and trajectories’, our approach shifts attention away from the singularities of national narratives of religious conversion, towards a deeper understanding of how religious beliefs, practices and identity were renegotiated by medieval people in their daily lives.  相似文献   
40.
Relying on stochastic frontier analysis we propose a methodology to study the technological characteristics and cost efficiency levels related to the provision of public infrastructure for basic utilities. The methodology assumes a cost minimizing behaviour on the part of public officials when planning the construction of local infrastructure, which is represented by way of a flexible translog cost function. Introducing relevant definitions of scale economies, associated with larger numbers of inhabitants and dwellings, as well as economies of density, brought about by reductions in urban dispersion, we analytically determine the optimal population densities for which average cost is minimized. We illustrate our model with the water cycle sector, including water distribution, sewage collection and cleansing of wastewater, and considering data at the municipality level for the Spanish region of Castilla y León. The obtained results indicate potential cost savings in the form of decreasing average costs, as relevant scale and density economies are present, along with large inefficiency levels. Relevant policy guidelines favouring larger and denser urban sizes are drawn, as the observed cost excess is the result of a general suboptimal urban size in terms of population density, and the negative effects of dispersed settlement patterns.  相似文献   
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