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21.
Through the history of human occupation in the south-central Andes, the interactions between south-American camelids and human populations were essential in the social reproduction, being hunting one of the appropriation modes of greater long term. In this sense, the way in which encounters between hunters and their preys were materialized becomes a relevant subject in order to understand these interactions. That is why in this paper I pretend to show the way in which the landscape were constructed where the encounters between hunters and their preys were given. For this, I shall focus in the information obtained from the intensive and systematic survey developed in the Antofalla valley, located in the Antofagasta de la Sierra Department, Catamarca Province, Argentina. This information has allowed me to identify a series of structures build with the aim of propitiate the encounter of herds by means of anticipating the movements of the animals, searching to obtain near and fixed targets in order to materialize the attack.  相似文献   
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ABSTRACT Regional differences in real wages have been shown to be both large and persistent in the United States and the U.K., as well as in the economies of other countries. Empirical evidence suggests that wage differentials adjusted for the cost of living cannot only be explained by the unequal spatial distribution of characteristics determining earnings. Rather, average wage gap decomposition reveals the important contribution made by regional heterogeneity in the price assigned to these characteristics. This paper proposes a method for assessing regional disparities in the entire wage distribution and for decomposing the effect of differences across regions in the endowments and prices of the characteristics. The hypothesis forwarded is that the results from previous studies obtained by comparing average regional wages may be partial and nonrobust. Empirical evidence from a matched employer–employee dataset for Spain confirms marked differences in wage distributions between regions, which do not result from worker and firm characteristics but from the increasing role of regional differences in the return to human capital.  相似文献   
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The inorganic and organic fractions of two microsamples of prehistoric paint from the same site, the Minateda rock shelters, are analysed here for the first time. The two samples correspond to two rock shelters of different styles (Levantine and schematic) – Abrigo Grande de Minateda (The Great Rock Shelter of Minateda) and Abrigo del Barranco de la Mortaja (Del Barranco de la Mortaja Rock Shelter). Since its discovery, historiographical tradition has emphasised the Abrigo Grande de Minateda, with its magnificence and complexity, as emblematic of the origin and evolution of rock art in the Mediterranean Basin of the Iberian Peninsula (a UNESCO World Heritage Site). Four complementary techniques –Microphotography, Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy (SEM-EDX), Raman Spectroscopy and Gas Chromatography–Mass Spectroscopy (GC–MS)– were combined to identify and characterise the physicochemical properties of the paint and of the surface. We present an interpretation of the results that leads us to define complex taphonomic alterations beyond the usual distinction of layers that include the surface, pigments and patinas.  相似文献   
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A total of 11 340 Cartesian coordinates of 42 homologous landmarks on five excavated human crania were recorded by three observers using a three‐dimensional (3D) digitiser and computer models created with a 3D laser scanner. The aim was to compare the errors of the coordinate data of landmarks of different types recorded with these two techniques. The results showed that digitiser‐based and 3D model‐based coordinate measurements had overall standard deviations of, respectively, ±0.79 and ±1.05 mm. However, the 3D digitiser yielded the most precise coordinate data for landmarks defined primarily by biological criteria (Type I landmarks), while the 3D laser scanner models yielded the most precise coordinate data for landmarks defined primarily by geometric criteria (Type III landmarks). These findings are likely to influence the research design of future craniometric studies, as they indicate that the suitability of certain landmark types as reference points for geometric operations, such as partial Procrustes analysis, depends on the method by which they are measured. This information is particularly important for retrospective research or for combined databases such as FORDISC or CRANID, which may integrate different types of landmarks recorded by different researchers and/or instruments. Crania displaying poor preservation and surface discoloration yielded larger measurement errors, especially for the 3D model measurements. This is not surprising given that landmarks on 3D models cannot be located using tactile means, but have to be located solely on a visual basis. Nonetheless, even though the digitiser measurements exhibit an overall precision slightly greater than the 3D model measurements, both techniques yield coordinate data with a precision sufficient for most craniometric research. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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The ever-increasing concentration of people and economic growth in the largest cities relative to the rest of the country has slowed down or even reversed in many of the developed European countries over the last decade. This trend contradicts what the global cities, urban economics and new economic geography literature would predict. This trend can be interpreted from two points of view: (1) the trend is due to large obstacles to further large city urbanization and thus is inefficient or (2) this trend highlights alternative pathways to growth than the mega-city approach and may be as, if not more, efficient. This trend may be linked to Europe's uniquely polycentric urban structure with high number of small- and medium-sized cities. In addition, improvements in the access to services, including broadband, outside large cities may have facilitated the higher growth rates of smaller centres and rural regions and increased their appeal for residents and firms. Last but not least, negative externalities in the large cities, such as congestion costs, pollution, labour crowding and high cost of living, may increase the appeal of smaller centres and rural regions.  相似文献   
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The wave of sovereign defaults in the 1890s was one of the worst ever remembered in the history of finance. From Argentina in 1890 to Brazil in 1898, countries in Latin America and Southern Europe defaulted on their external debt, inflicting investors with huge losses. However, this was the last cluster of defaults of the gold standard era. At the beginning of the 20th century and until the outbreak of World War I, defaults were less frequent despite the continuous increase in foreign government borrowing. The literature has provided several explanations on this apparent success all relative to improvements introduced in the market. This paper argues that the fall in the number of defaults is more related to a more favorable world macroeconomic environment and to an increased liquidity available in international financial markets than to an abrupt shift in the manner in which defaults were handled. I show that settlements were more correlated with the relative facility to re-access foreign capital markets than to changes in the financial architecture.  相似文献   
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