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11.
In the Andes, there are several pre-Hispanic irrigation networks with structures destined for water storage. However, it has not been widely discussed in archaeological research. This is probably due to their being difficult to identify. The aim of this study is to explore the use of diatom assemblage analysis as a methodological tool suitable to help in the identification and characterization of these ancient hydraulic structures. We analyzed two archaeological structures interpreted as water reservoirs from north-western Argentina (EH1 in Antofagasta de la Sierra and U-88R1 in Yocavil) and compared them to current reservoirs. The diatom species composition and the changes in the dominant ecological groups in the studied structures highlight different periods of hydraulic behavior. EH1 contained and stored water, but there were periods of time in which there was a lack of use or abandonment of the structure. However, the U88-R1 structure does not have diatom evidence of containing standing water for a prolonged time but presence of wet soils. Thus, the structure could have been used for other water management strategies. The results show that diatom analysis is a methodological tool with a high potential to study ancestral hydrotechnologies.  相似文献   
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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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The standard theory of optimal jurisdictional size hinges on the existence of economies of scale in the provision of local public goods and services. However, despite its relevance for forced local amalgamation programs and related policies, the empirical evidence on the existence of such economies of scale remains elusive. The main goal of this paper is to produce an updated and comprehensive quantitative review of the existence of economies of scale in the provision of local public goods using a meta-analysis approach to systematize the wide range of empirical approaches and modeling frameworks found in the previous literature. Our analysis confirms the presence of moderately increasing to constant returns to scale in the provision of local services with no reduction in the average costs of production in the delivery of most local public services beyond a certain, modest jurisdictional size, which many studies have estimated at 10,000 residents. Also, the potential for economies of scale differs at least across three traditional services: education, water and sanitation, and garbage collection, being highest for education and lowest for garbage collection. Our analysis also offers guidelines for future empirical research in this area. Physical output and production cost data should be used, together with translog specifications for the modeling of cost functions. Last, we find evidence that the determinants of output cost elasticity include bidirectional publication bias and population density but do not include the presence or absence of modern “lean” production technologies or the (perceived) capital intensity of the sector, contrary to conventional wisdom. These findings have significant policy implications for countries considering jurisdictional consolidation programs.  相似文献   
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Tráfico de Indias y política oceánica. By Fernando Bordejé Y Morencos. Madrid: MAPFRE, 1992. Pp. 341.

Relaciones económicas entre España y América hasta la independencia. By John R. Fisher. Madrid: MAPFRE, 1992. Pp. 280.

Las comunicaciones en América. By Secundino‐José Gutiérrez Alvarez. Madrid: MAPFRE, 1993. Pp. 424.

Piratas, bucaneros, filibusteros y corsarios en América. Perros, mendigos y otros malditos del mar. By Manuel Lucena Salmoral. Madrid: MAPFRE, 1992. Pp. 306.

El dinero americano y la política del imperio. By María Emelina Martín Acosta. Madrid: MAPFRE, 1992. Pp. 333.

Cargadores a Indias. By Julian B. Ruiz Rivera and Manuela Cristina García Bernal. Madrid: Mapfre, 1992. Pp. 395.  相似文献   

18.
Concepts of unemployment or of the labour market are not abstract, but develop from each society's own particular logic. Taking the examples of Germany and France at the end of the nineteenth century, it is possible to see how these concepts were constructed in specific national contexts, and how they were then used in practice. This analysis leads us to rethink current ideas about work and unemployment, and to ask what their future will be in a united Europe.  相似文献   
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The present paper surveys the discussions conducted by official statisticians regarding the ideal structure according to which a national data collection system should have been designed if it was to meet the challenges put up by the various transformation Western countries have undergone since the beginning of the 19th century. Arguments in favour of coordination, centralization, or decentralization have emerged for the first time in 1832 Britain, when the Statistical Bureau of the Board of Trade was created. Up to 1945, this debate went on, the industrial take-off, the economic crises, and the world wars all being occasions for its protagonists to put forward their preferred view. The perspective we take here is original in two respects: on the one hand, instead of confining ourselves to the major statistical systems (those of France, Britain, and the USA), we intend to evoke a large number of cases and, from this comparative standpoint, propose a general account of the drive towards centralization; on the other hand, instead of restraining our-selves to the 19th century, we cover the entire time-frame extending from 1800 to 1945.  相似文献   
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