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71.
The study presents criteria to distinguish some of the nonhuman predation on birds whose remains may also be found at archaeological sites. Specifically, it deals with fragmentation patterns of bird bones in uneaten food remains of the white-tailed eagle Haliaetus albicilla and discusses perforations in victims' bones done by the white-tailed and golden eagles. The food remains show very low degree of fragmentation; bones of the pectoral girdle and wing predominate while head and leg elements are poorly represented. The proportion of perforated sterna differs between the two species of eagles and it is suggested that the differences are attributed to the species of prey rather than the way of handling them by the raptors.  相似文献   
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So far, the relationship between Industrial Districts (IDs; clusters of interconnected local industries) and migrant enclaves (areas with a high concentration of international migrants from a single nationality) has been studied mostly by focusing on the emergence of ‘ethnic enclave economies’ within the district and/or by highlighting racist conflicts that achieved notoriety in the media. In this study, we contend that there is a more general and complex interaction between the two phenomena. This interaction is mediated by the local context, national regulations, and the organization of the international market, among other factors. By focusing on the case of the ceramic ID of Castelló de la Plana (Spain), we show how this ID with a high rate of job formality, combined with other job opportunities and a unique ‘institutional completeness’, set up the conditions for a non-conflictive Romanian migrant enclave that reached 14% of the town’s total population in 2012. Finally, and also considering another case study of ID and migrant enclave (Prato, and its Chinese enclave), we suggest a model of interaction that should be interpreted taking into account the general dynamics of the international organization of value and the requirements of flexibility and reduction of costs that frame IDs.  相似文献   
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Using data for the 50 U.S. states we relate industry-specific employment growth rates over the period 1976–1989 to the industrial compositions of the states in 1976. We explore the idea that services and manufacturing are inextricably linked and that this interdependence may be beneficial to manufacturing (through knowledge spillovers, for example). Specifically, we test whether the manufacturing sector grew faster in service-based economies. Our evidence does not support the idea of cross-fertilization from services to manufacturing.  相似文献   
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The period of European maritime expansion that started in the fifteenth century had a great impact on trading, on human migrations and consequently in the dispersion of infectious diseases. Portugal was at the core of this expansion; however, studies about parasitic infections, especially helminths, are lacking. This study aims to help reduce this gap presenting the results of microscopic analysis of soil sediments collected from the São Jorge churchyard of Sarilhos Grandes (Montijo). Consecrated in the fourteenth century AD, it remained as a burial ground until the nineteenth century. Soil samples collected from the pelvic girdle of five adult individuals and samples taken as control were analysed under the microscope after current conventional methodological procedures were undertaken. Eggs from Ascaris lumbricoides were identified. Also eggs of trichostrongyle type species were identified in two individuals and may represent the first report in archaeological European samples. Food remains include potato and rice starches, muscle fibres, bivalves, pollen grains and fungi spores. The stratigraphy interpretation together with potato findings put the oldest skeletons to a chronology around the sixteenth century AD. These results are consistent with historical sources that documented the prominence of Tagus river nearby villages in maritime expansion.  相似文献   
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Desalination of rocks used in monuments is a common strategy to reduce the possibility of deterioration by soluble salt crystallization processes. In the last years, some laboratory studies have demonstrated that the application of electrokinetic techniques allow to achieve higher desalination effectiveness, overcoming most limitations of the traditional methods. However, to our knowledge no studies have been conducted on the effectiveness of this technique for in situ desalination of granite. The present study is aimed at filling this gap. The results of an in situ desalination intervention using electrokinetic methods, on a column highly contaminated with salts are presented. The desalination method was optimized to desalinate large in situ structures, trying to establish the necessary protocols (buffering system, irrigation system, setup, etc.) to obtain results as satisfactory as those obtained in laboratory. The results demonstrated the high effectiveness of this method in terms of total salt extraction and depth of salt extraction. The concentration of anions in the column was decreased by more than 80% after 55 days of treatment. No mineralogical and aesthetic damages on the stone were detected after the treatment, confirming the reliability of this method to be applied in situ on granitic rocks.  相似文献   
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