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11.
A vibrant artisanal fishery of the brackish water marsh clam (Polymesoda acuta) is located in the lower Río Tempisque, Costa Rica. Fishermen harvest clams from shoals according to tidal and lunar cycles. They take most clams directly to riverside processing stations to be cooked and sold as salted meat, although some cooked clams are dried, and others sold live. Processing activities result in the formation of shellmounds that share significant similarities and some differences with ancient marsh clam shellmounds of coastal Chiapas, Mexico. In this study, procurement and processing activities are described and quantified, revealing the substantial amount of labor and skill involved in the modern fishery. Implications for archaeological preservation and predictions from optimal foraging theory are evaluated.  相似文献   
12.
ABSTRACT

The “Quartel das Esquadras” is an 18th century infantry barrack located within the limits of the bulwarked fortress of Almeida, in Portugal. An ongoing adaptive reuse project of the building aims to recover its full capacity and also its importance, by implementing a variety of new uses. The architectural intervention results in the need of the structure to withstand new and diverse imposed loads. As the current configuration of the structure will be altered, the main objective of this article is to evaluate the suitability of some of the proposed structural interventions. The current condition has been characterized following a multidisciplinary approach comprising historical research, visual inspection, non-destructive testing, and structural analysis to identify the possible sources of major structural problems. A portion of the building particularly affected by the alterations has been selected to carry out structural analysis. A comparative safety assessment of the selected area in both current and altered condition has been done through finite element modelling and nonlinear static analysis, resulting in an identification of the weaker points against the new implemented loads and alterations. Finally, proposals for the implementation of the studied intervention, as well as recommendations for future research and analyses, have been given.  相似文献   
13.
ABSTRACT

This article focuses on the trading trajectory of an Uzbek family of merchants from Tajikistan. This family runs businesses in both Tajikistan’s capital, Dushanbe, and China’s famous international trading city: Yiwu. The analysis is centred on the accounts placed by Tajikistan’s Uzbek merchants about their historically sustained experience, often across several generations, in trading activities. These merchants’ claims of belonging to a ‘historical’ trading community rather than being ‘newcomers’ to long-distance commerce are articulated in relation to notions of ‘hierarchies of trade’ as they evolve in a twofold relational model linking Yiwu’s Changchun neighbourhood and Dushanbe. I suggest that the forms of conviviality enacted in Yiwu’s Changchun neighbourhood need to be understood in terms of the historical, multinational and transregional contacts that have occurred within the spaces of the former Soviet Union, as well as along the China-Russia and China-Central Asian borders. Equally, the hierarchies of trade of Uzbek merchants from Tajikistan in Yiwu’s Changchun neighbourhood cut-across markers of identity that juxtapose the roles of Tajik and Uzbek communities in Tajikistan’s contemporary politics and economics.  相似文献   
14.
Archaeological fieldwork conducted on a plot of land near the town of Chia (Colombia, South America) uncovered the remains of a small Muisca settlement occupied from the late Prehispanic period to the colonial period. The excavation program documented particular sets of features including postholes, pits, colored floors, and a burial. These elements provided a baseline for reconstructing the ground plans of perishable structures and architectural spaces. The components of built areas were key cultural referents for the peoples who lived in La Maria during the Prehispanic period. Important changes in the arrangement of the elements that comprise architectural space are observed during the colonial period, arguably as the result of important transformations in native culture.  相似文献   
15.
This study argues for more comparative research between seemingly different migrant groups, bringing a new focus on intra-European migration in Portugal by examining and comparing the reasons why migrants from different geographical origins choose to settle in the tourism-based Algarve region. Drawing on data collected from a questionnaire survey and interviews, the study first compares the profiles of two apparently distinct migrant groups – Northern and Eastern Europeans – and goes on to explore their discursive representations of migration experiences. Findings reveal that despite differences in initial motivations for moving to the Algarve, there are similarities between the two groups in terms of what leads them to settle in the region. Among both groups there is a high level of positive place-identity, suggesting that the specific context of the destination place plays a significant role in positive post-migration outcomes, something which is often overlooked in migration studies. Furthermore, the lived and perceived lifestyle affordances of the destination place, especially when discursively compared with the place and lifestyle left behind, are flagged by both groups and lend support to the idea that the role of lifestyle in migration has a wider significance than is usually credited.  相似文献   
16.
This paper describes environmental systems games developed for energy and water resource use designed to be adaptable from high school to undergraduate use. Two of the games are computer simulations with adjustable levels of difficulty that can be done in a computer lab or as a homework assignment. The third is a peer-to-peer roleplayer game designed for an immersive in-class simulation. For the energy and the peer-to-peer water games, we describe (1) the overall strategy or story line adopted, (2) the manner in which the game is played by students in a classroom setting, (3) the use of scientific literature in conceptualizing and parameterizing the game, and (4) possible game extensions. Preliminary data from use at the undergraduate level shows that the games are very well-received by students and, consistent with other research on quasi-experimental simulations, likely enhance learning outcomes.  相似文献   
17.
A. Tarriño 《Archaeometry》2015,57(5):928-948
A new classification system is proposed to describe the volumetric formats of clastic lithic products of geological and archaeological origin. In order to build this operative classification, the rectangular block or cuboid is established as the standard geometric format to represent their three‐dimensional format (the X‐axis being length or long diameter, the Y‐axis being the width or intermediate diameter, and the Z‐axis being the thickness or short diameter) on a two‐dimensional diagram. To obtain this graph, each absolute coordinate (X, Y, Z) defining the prisms is projected on to an auxiliary plane with a new set of relative coordinates (x, y, z), expressed as the percentage of their sum. The projection generates a triangular diagram on which the indices of elongation and flatness are represented. A geometric transformation converting the triangular diagram into a quadrangular diagram has been produced in order to better represent the scatter points. Then, a double scale is necessary: (i) an absolute scale to quantify the indices, and (ii) a relative scale to calculate where the graphic locus is projected. This new graph also allows us to work with statistical parameters. Finally, two classic examples of applications selected from the literature are shown.  相似文献   
18.
This paper evaluates the impact of accessibility on the productivity of Spanish manufacturing firms. We suggest the use of accessibility indicators of workers and commodities, integrating transport, land use, and individual components, computing real distances or traveling times using the Spanish full road network. Estimated firms’ total factor productivity is explained as a function of the accessibility indicators and additional control variables. Results evidence the crucial role on firms’ productivity to the accessibility of commodities and to a slightly lesser extent the workers.  相似文献   
19.
20.
Despite phytoliths having been used to understand past human use of plants and palaeoenvironment in Middle Paleolithic sites, little is known on this aspect in the well-documented central region of Mediterranean Iberia. This paper presents the first phytolith and mineralogical study conducted at Abrigo de la Quebrada (Chelva, Valencia). Forty-one samples were analyzed through phytoliths and Fourier transform infrared spectroscopy (FTIR) from different areas, stratigraphic levels, and archeological contexts (hearth, hearth-related, and non-hearth-related sediments) of the shelter. The results obtained point towards a different pattern of preservation in the site depending firstly on the stratigraphy and secondly on the area where the samples were collected. Postdepositional processes that may have chemically affected phytolith preservation are discussed. Grasses are the main plant component identified in all the samples while woody plants are scarce. The abundance of grasses in the non-hearth-related sediments might be related, at least partially, to the dispersion of ashes from hearths, as indicated by the FTIR results. The results are indicative of an occupation of the site during the spring-autumn season. At this time, the area would be dominated by a semi-open environment with supramediterranean vegetation.  相似文献   
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