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Human bones from Late Eneolithic graves and Bronze Age settlement pits in Moravia (Czech Republic) were studied to reconstruct their post-mortem histories based on the distribution of their microbial destruction. Backscattered electrons in a scanning electron microscope (BSE-SEM) were used for visual assessment of bioerosion. Visual data from the histological analysis were transformed into quantitative data using the Waikato Environment for Knowledge Analysis (WEKA) toolkit. The results show that the presence of bioerosion is different between the two groups of samples. The bones from settlement pits display extensive bioerosion whereas the bones from graves display no or arrested bioerosion. The absence of bioerosion in graves is most probably linked with tomb burials of Corded Ware Culture. Given the tombs are frequently not preserved archaeologically, the state of bone bioerosion may serve as an indicator of their existence. 相似文献
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Darío Alejandro Ramirez María José Herrera-Soto Josefina González Andreu Francisca Santana-Sagredo Mauricio Uribe Rodríguez Rodrigo Nores 《Archaeometry》2023,65(5):1073-1089
Faunal remains from archeological sites worldwide, especially feces and regurgitated pellets, are usually subjected to paleoparasitological examination, allowing the identification of past animal parasites. In this study, we analyzed 10 samples of South American camelid dung, which played an important role for the ancient human groups in the South-Central Andes, dated between 341 and 1635 calCE, from the Iluga Túmulos site (Pampa del Tamarugal, Tarapacá region, Atacama Desert, Chile). Microscopy examination revealed parasite remains in seven samples, in which oocysts of Eimeria macusaniensis and eggs of Lamanema chavezi/Nematodirus lamae, Trichuris sp., Moniezia sp., capillariids, strongylids, and unidentified nematodes were found. Although some of these species pose a potential health risk to camelids, most are not considered to be of major zoonotic importance, which could explain the absence of these parasites on human coprolites from this site analyzed previously. This first paleoparasitological study on camelid fecal remains from northern Chile sheds light on the occurrence of gastrointestinal parasites and its relationship with Andean ancient human populations and the environment. 相似文献
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Damiaan Persyn Javier Barbero Jorge Díaz-Lanchas Patrizio Lecca Giovanni Mandras Simone Salotti 《Journal of regional science》2023,63(4):755-792
We analyze the general equilibrium effects of an asymmetric decrease in transport costs, combining a large-scale spatial dynamic general equilibrium model for 267 European NUTS-2 regions with a detailed transport model at the level of individual road segments. As a case study, we consider the impact of the road infrastructure investments in Central and Eastern Europe of the European Cohesion Policy. Our analysis suggests that the decrease in transportation costs benefits the targeted regions via substantial increases in gross domestic product (GDP) and welfare compared to the baseline, and a small increase in population. The geographic information embedded in the transport model leads to relatively large predicted benefits in peripheral countries such as Greece and Finland, which hardly receive funds, but whose trade links cross Central and Eastern Europe, generating profit from the investments there. The richer, Western European nontargeted regions also enjoy a higher GDP after the investment in the East, but these effects are smaller. Thus, the policy reduces interregional disparities. There are rippled patterns in the predicted policy spillovers. In nontargeted countries, regions trading more intensely with regions where the investment is taking place on average benefit more compared to other regions within the same country, but also compared to neighboring regions across an international border. We uncover that regions importing goods from Central and Eastern Europe enjoy the largest spillovers. These regions become more competitive and expand exports, to the detriment of other regions in the same country. 相似文献
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Gísli Pálsson 《Anthropology today》2023,39(3):1-2
This guest editorial reflects on the relevance of anthropology for extinction concerns, a rapidly expanding practical, ethnographic and theoretical space at a time of impending mass extinction. While biological extinction is necessarily a multispecies development (usually implicating humans), traditional species talk – focused on taxonomies, collections and classification – needs critical rethinking as it necessarily diverts attention from the vitality of life. The broad discipline of anthropology has much to offer for understanding processes of extinction and recovery, fleshing out habitat problems and prospects of extinction, and advancing meaningful environmentalist practices. 相似文献
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ABSTRACT. We reexamine the price structures and their welfare implications in three pricing regimes (mill, uniform and discriminatory) for a monopoly. We show that spatial price discrimination could provide the highest social welfare and, when consumers tastes are heterogeneous enough, also the highest consumer surplus. The superiority of spatial price discrimination is partially due to the larger output produced and partially due to differential treatment for consumers with heterogeneous tastes. 相似文献