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A non-invasive procedure for assessing and interpreting the pigments of rock art paintings through computer vision and photogrammetric techniques is presented. The method is designed to document and interpret poorly preserved pigments by making use of advanced techniques of photogrammetry and computational imaging. Two different software solutions that were developed by the authors have been used for this purpose. Finally, two case studies of rock art paintings from Spain have been analysed, which show the reliability of the method.  相似文献   
33.
Based on a qualitative methodology that includes in‐depth interviews conducted between 2008 and 2017 with 180 migrant smugglers from Mexico, the objective of this paper is to analyse the way US employers' interest in having access to cheap labour feeds migrant smuggling, and is connected to corruption in US border enforcement. We conclude that corruption on the US side of the border could be systematic and not a matter of a few bad apples. Corruption is manifested in selective enforcement, which is a pragmatic practice that justifies enhanced immigration enforcement, and benefits US immigration agents, US employers and Mexican smugglers, while undocumented border crossers suffer the monstrous effects of militarised border enforcement.  相似文献   
34.
Small and medium-sized cities represent the backbone of the European territory, promoting cohesion and an economic base for development. The study compares the spatial and temporal trajectories of land use in three small/medium-sized cities located in central Portugal, between 1958 and 2011. The cities of Viseu, Leiria and Castelo Branco were chosen because they are located in different urban sub-systems and because of the different factors that frame their alterations in land use, occupation and consequent urban development. The research evaluates the transformations, supported by indicators to explain the spatial dynamics of losses and gains and a principal component analysis compares the land-use trajectories for the three cities. The general results reveal an increase from the central part of the study areas to the periphery, contrasting with a continuous decrease of the agricultural parts, illustrating peri-urbanization and rururbanization processes. The study allows identification of the dynamics in the three analysed areas, highlighting the different rhythms of change and relating them to the particularities that exist in each city. The methodology represents an advantage for the analysis and evaluation of territorial dynamics related to land-use change, and made possible the identification of the different forces.  相似文献   
35.
The role of coastal resources in the subsistence strategies of Palaeolithic human populations has only recently become an important topic in Old World archaeology. Information on the exploitation of these resources, both as foodstuffs and symbolic elements, can be used to infer the emergence of modern human behaviour as well as to track the diversification and intensification of human diet over time. The excavations carried out at El Cuco rockshelter, located in northern Spain have provided evidence for the exploitation of marine resources during the Early Upper Palaeolithic. The accumulation of Patella shells at El Cuco provides the largest accumulation and the first clear evidence of collection and consumption of molluscs during the Aurignacian on the Atlantic Façade of Europe. A deposit of ornamental shells appeared in a very homogeneous context dated to the Gravettian, suggesting that the shells belonged to the same item. The analysis of this evidence has allowed us to conclude that marine resources were systematically used at least from the beginning of the Upper Palaeolithic in the region. However, a comparison with the Mesolithic shows that intensive shellfish gathering did not occur until the end of the Upper Palaeolithic. Regarding the ornaments, it is interpreted that the identified shell beads were used as social or personal status markers.  相似文献   
36.
In the island of Jaina, Campeche, red and yellow pigmented bones have been found. The study of the yellow and red colors in these burials is important for their possible interpretation, either religious, intentional coloring, or to understand taphonomic processes such as reactions of the original pigments with other compounds. Yellow color on bones is unusual in prehispanic burials.  相似文献   
37.
The differences between boiled or unboiled bones are not often studied. However, they are crucial to understand postmortem rituals and to establish defleshing procedures and mortuary practices. In this work, human bones boiled in sea or fresh water are characterized. The bone composition, as well as the compounds present in the resulting materials, shows that salt alters the boiling process mechanism. Hence, from structural and morphological criteria, it is possible to distinguish if a bone has been boiled in salt or fresh water. In both sets of samples, the smoothness of the bone surface depends on boiling time, but only in bones boiled in seawater, filaments are observed apparently pouring out of the pores.Those differences which are mainly morphological (smoothness of the surface) are explained in terms of a collagen diffusional mechanism favored by sodium and chloride ions. For a boiling time of 6 h, the surface is covered by a thick layer or crusts of degraded collagen. Experiments with seawater may be used as model experiments to simulate taphonomical alterations in bones exposed to salt water.  相似文献   
38.
The central role in Portuguese political culture of the identification of Portugal as a colonizing power legitimized a massive mobilization and violent response to the perceived existential threat of decolonization in the shape of prolonged wars in its main African colonies (1961–1974). If, however, this cultural myth of a Greater Portugal overseas was so powerful, how was decolonization eventually possible? The accumulated human and economic cost of facing three simultaneous, protracted anti-colonial insurgencies eroded this overseas creed and made Catholic and Marxist strands of anti-colonialism increasingly attractive to younger, more internationally connected, Portuguese elites. What also happened, however, this article will argue, was a refashioning of the powerful cultural myth of a special connection between Portugal and tropical Africa. A colonial myth was turned into a post-colonial myth legitimizing decolonization as a mutual and fraternal liberation from the same oppressive regime without a loss of strong ‘natural’ cultural bonds. More widely, the article aims to show that we cannot ignore the importance of cultural factors in international history. Our approach in this article is pluralist and this means that while arguing strongly for taking culture seriously and focusing on it, it does consider other, including more material, dimensions of power.  相似文献   
39.
The authors propose a scheme of economic regionalization for Cuba, based on Soviet Marxist principles. These include the idea of objective existence of a region, independently of man's will; the need for considering future developmental prospects; energy supply; the prerequisites for integrated development of the regional economy; the presence of a regional specialization; maximum promotion of a geographical division of labor, and the factor of the country's defense capability. The resulting system of six regions in described.  相似文献   
40.
In this study, we report a case of duplication of a lower fourth premolar (P4) on an Iberian wild goat from the archaeological site cave of Arlanpe, (Lemoa, Bizkaia, Northern Spain). The preserved right mandible corpus displays two premolars and the first molar (M1). Both premolars conform in size and general shape to fourth premolars (P4) but the medialmost of the two is rotated 90° counterclockwise, and thus, its wear pattern is different. The comparative analysis to other bovids and the relative scarcity of this anomaly compared to other cases of polydontia and hypodontia suggest that it is a developmental defect consisting in the duplication of the tooth germ, and we doubt on the potential of this abnormality as a territorially based indicator of past wild populations as has been previously proposed. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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