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1.
African Archaeological Review - A set of beads made of glass, gastropod mollusk shell, and fishbone from a Swahili occupation level on Ibo Island (northern Mozambique) is dated to the eleventh and...  相似文献   
2.
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   
3.
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   
4.
The aim of this article is to focus on the technology of archeological plasters at Teotihuacan (Central Mexico), from the Classic Period (200–650 A.D.), focusing in the study of Teopancazco, a neighborhood center in the city. Petrographic and chemical analyses by OM, SEM-EDS, and LA-ICP-MS were conducted to characterize samples from different constructive phases and sectors of the neighborhood center, to determine the provenance of the raw materials employed in the manufacturing (e.g., volcanic glass shards) and to assess whether a shift occurred in the manufacturing of plasters and in the procurement strategies of raw materials during the different phases. The results of the analyses show that almost no changes occurred in the making of the plaster during more than four centuries and allow us to consider the presence of a technological style in their manufacture, which is characterized by the making of plaster by mixing lime with volcanic glass shards, which in the case of Teopancazco were derived from the Altotonga (Veracruz) magmatic system. The data at our disposal suggest that this style was developed in Teopancazco and later introduced throughout the city of Teotihuacan in the Early Xolalpan phase (A.D. 350), although we still do not know whether the provenance of the raw materials is the same. The wide distribution of this technological tradition could be due to the technological properties of the materials and/or the influence of the intermediate elite who ruled over Teopancazco. The paper confirms that the study of material culture and technology sheds light on broader cultural aspects of ancient societies.  相似文献   
5.
Broca coined the neologism “aphemia” to describe a syndrome consisting of a loss of the ability to speak without impairment of language and paralysis of the faciolingual territories in actions unrelated to speech, such as protruding the tongue or pursing the lips. Upon examining the brains of patients with aphemia, Broca concluded that the minimum possible lesion responsible for aphemia localized to the posterior left inferior frontal gyrus and lower portion of the middle frontal gyrus. A review of Broca’s writings led us to conclude that (a) Broca localized speech, not language, to the left hemisphere, (b) Broca’s aphemia is a form of apraxia, (c) Broca’s aphemia is not, therefore, a terminological forerunner of aphasia, and (d) Broca was an outspoken equipotentialist concerning the cerebral localization of language. Broca’s claim about the role of the left hemisphere in the organization of speech places him as the legitimate forebear of the two most outstanding achievements of Liepmann’s work, namely, the concepts of apraxia and of a left hemisphere specialization for action.  相似文献   
6.
This article explores the linguistic experiences of transnational soldiers, using the Spanish Civil War as a case study. It argues that communication difficulties provoked by linguistic diversity within the Republican war effort and particularly within the International Brigades, caused the high command to move from a utopian, internationalist policy to a more pragmatic approach. The article evaluates the role played by language intermediaries in this evolving policy and in the wider Republican war effort. Finally, it argues that soldiers grassroots experiences of language contact forged new linguistic forms which underlined a strong sense of shared purpose and identity.  相似文献   
7.
The superposition of anthropogenic remains usually results in archaeological palimpsests, hindering an accurate characterization of the behavior underlying such remains. Aimed at facing this methodological constraint in the study of Palaeolithic contexts, we present a contextual approach to Neanderthal settlement dynamics based on an understanding of lithic assemblage formation processes. We focused on a set of lithic artifacts from the Middle Palaeolithic site of El Salt. With the goal of isolating temporally constrained units of behavioral analysis, we analyzed the spatial distribution of lithic, faunal and combustion remains. Then, the lithic records from each of the resulting units were analyzed from a genetic and technical perspective. This goal was achieved by identifying lithic Raw Material Units (RMU) through observations on reduction processes, refits and their spatial distribution. Our results suggest that El Salt SU X lithic remains represent several diachronic human occupation episodes and different site functions. This study illustrates the benefit of investigating lithic assemblage formation processes to alleviate the palimpsest problem in Palaeolithic contexts.  相似文献   
8.
This study examines the diet consumed by the population at the neighborhood center of Teopancazco, Teotihuacan, in the basin of Mexico. We used stable isotope analysis of δ13C and δ15N of the dentine collagen as well as the δ13C from enamel bioapatite from teeth (M2 and M3) of 39 of excavated burials. The results show that the diet consumed by the majority of the population during childhood and adolescence had high 13C enriched values in both dietary components: δ13C enamel_bioapatite = ?2.0 ‰ ± 1.5 for the whole diet and δ13C dentine_collagen = ? 9.4 ‰ ± 2.1 for the protein component. According to the bi-variable and multivariable models, some individuals consumed higher amounts of C4/CAM resources than those specified in cluster #2 (70 % C4 diet; ≥50 % C4/CAM protein). An inter-tissue adjustment of 2.3 ‰ was used to relate the enamel bioapatite data to the bone bioapatite of the models. Average δ15Ndentine_collagen was 10.2 ‰ ± 2.8 with high variability especially for four individuals, three of which belong to special burials, suggesting different access to meat or marine products due to their social or migration status and/or to pathological conditions. The data suggest that maize was the staple crop of the population not only at Teopancazco but for Teotihuacan as a whole, in the form of tortillas, tamales, atole, and protein from maize-fed animals with the inclusion of other CAM, C4, and C3 resources probably from the bountiful ecosystem of the basin of Mexico or from the wide trade system that Teotihuacan had with Mesoamerica.  相似文献   
9.
Archaeological research in central‐northern Patagonia (Atlantic coast and lower the valley of Chubut river) showed that this area was used since at least the Middle Holocene. Stable isotope analyses (13C and 15N) of human bone samples indicate that hunter‐gatherers living in that area had a terrestrial‐marine diet including guanaco meat, land plants, mollusks and pinnipeds. Despite this general trend, intersite variability and changes through time were noted, especially after the late Holocene. These results have been reinforced by archaeofaunal, technological and bioarchaeological records. In this paper, three hypotheses are examined: (a) the diet of these populations was complete and rich enough to ensure good health status and avoid nutritional deficiencies; (b) carbohydrate consumption increased progressively after 1000 BP, when pottery technology was adopted and (c) this kind of mixed diet would have been qualitatively more nutritious than that of other populations of the region, which would have resulted in better nutritional and healthy conditions. These three hypotheses are compared with dental results obtained from 563 permanent teeth from 45 individuals (34 adults and 11 juveniles from both sexes), rescued from burial sites. Indicators of oral health were assessed through the observation of caries, abscesses, wear, pulpar cavity exposure and ante mortem loss. Features of nutritional status such as enamel hypoplasia, porotic hyperostosis and cribra orbitalia were also examined. Given the availability of direct radiocarbon dating for most of the sample, three temporal series were determined: ‘Before 1000 BP’, ‘1000–5000 BP’ and ‘Post‐contact’. No evidence of alimentary stress or iron deficiency was found in individuals from the three series, which accounts for healthy and good nutritional life conditions. After 1000 BP, the results show a progressive increase in the caries percentage and a decrease in abscesses, dental wear and ante mortem losses frequency. This is possibly related to more consumption of processed foods in the last 1000 years. These results were compared with similar studies based on samples from different environments and latitudes of Patagonia. Evidence suggests that mixed diets (marine‐terrestrial) would have been more appropriate and nutritionally complete than exclusively marine or terrestrial diets. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
10.
Companhia Aurifícia is located in Porto, Portugal, and was founded in 1864. It was a pioneer factory in the industrial production, casting, rolling, and stamping of metallic objects and laboured for about 150 years, in areas as jewelry, manufacture of parts in silver and gold or the production, and casting of various metals. In 1866, it began laboring in Rua dos Bragas, its present location, and in 2003 ceased all activities.Companhia Aurifícia is an industrial complex including several buildings, all located in the same block. It is a precious example of the industrial architecture in Porto, where the still existent retaining walls, structures, machinery, and decorative elements make it one of the last examples of 19th century industrial life of the city.This article aims to evaluate the safety condition of one of the buildings included in this industrial complex, in order to propose the necessary strengthening interventions.  相似文献   
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