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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.
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   
9.
The hydrogen isotope systematics of hair have been explored and several applications demonstrate the type of information that can be recovered from archeological and forensic hair samples. Experiment with modern hair demonstrate that sources of protein-based hydrogen in keratin are food and water. On the basis of a deuterium-enriched drinking study, it was found that 31% of hydrogen in human hair is derived from ingested water. At least 9% of total hydrogen in human hair is isotopically exchangeable with water or water vapor at 25 °C. Nearly complete exchange occurs in a matter of hours. The δD value of body water is approximately 17±10‰ (n=7) more negative than human hair, although there is much scatter in data for modern hair, which is clearly related to variability of the isotopic composition of ingested food and water. Archeological hair samples were analyzed from (i) a 370 year old Incan mummy sacrificed at 5300 m altitude in Argentina (Geoarchaeology 14 (1999) 27) and (ii) from a Woolly Mammoth from Siberia. High spatial resolution data along the length of hair from the mummy indicate seasonal variations in carbon, nitrogen and hydrogen isotope ratios. No hydrogen isotope anomalies are seen in the youngest hair at the base of the scalp, indicating that the individual probably lived at 1600 m, and spent less than a week at high altitudes before death. The mammoth also preserves a seasonal signal, suggesting hair growth rates of 33 cm/year, faster than human hair, but slower than horse tail hair. The limited isotopic range across seasons for the mammoth is consistent with a north-south migration on the order of 1000 km.  相似文献   
10.
Stone boiling is one of the principal cooking methods used by hunter-gatherer societies. The present paper proposes behavioral and organizational inferences as to how stone boiling was incorporated into hunter-gatherer subsistence practices through an examination of a shallow-basin hearth in an Early Magdalenian level (c. 15,500 14C B.P.) of El Mirón Cave, Cantabria (northern Spain). Exploratory analysis of spatial patterns of archaeological remains (bones, lithic artifacts, and fire-cracked rocks) and use-life analysis of fire-cracked rocks demonstrate that the hearth was used and maintained during visits of humans who preyed mainly on ibex and red deer near the site. The relative accessibility of these ungulates and cost-induced technology of stone boiling suggest the implication that stone boiling was employed to maximize the energy and nutrition obtained from carcasses of these game taxa under the circumstance of resource intensification.  相似文献   
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