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61.
Certain trace elements may accumulate in bone in relation to dietary habits, so some of them are of interest in paleodietary analysis. This is the case with strontium (Sr) and barium (Ba), whose potential value as paleodietary indicators is enhanced by their relatively inert metabolic behaviour. The presence of carious lesions may indicate consumption of sugar and vegetables, whereas the etiology of dental calculus deposition is multifactorial, although some authors consider this as an indicator of protein consumption. Based on these facts we analysed (1) Ba, Sr, and calcium (Ca) content of inner cortical bone obtained from the ramus mandibularis, by atomic absorption spectrophotometry, (2) presence of teeth with carious lesions, and (3) presence of teeth with calculus deposition in 62 mandibles. All samples were obtained from the church La Concepción, an 18th century burial place in Tenerife. Gender was assessed by analysing genetic expression of amelogenin in some cases (14), and by inspection of pelvic bones when available (41 cases). We found (1) Carious lesions in 32 cases, and dental calculus, in 39; no association was observed between sex and presence of dental caries or calculus deposition, nor between the sex and the proportion of carious teeth nor the proportion of teeth with calculus deposition; (2) people buried near the altar (priests and individuals of the highest social class) showed a significantly higher proportion of teeth with dental calculus deposition (χ2 = 5.36, p = 0.021); (3) bone Sr and bone Ba were significantly higher than the values observed in a control group of 10 modern omnivorous individuals; the lowest Sr values were observed among people buried near the altar; and (4) the Ba/Sr ratio was directly related with the proportion of teeth with carious lesions. These data suggest that there were differences in dietary pattern among the individuals belonging to different social classes; overall, consumption of vegetables was widespread, as shown by the high proportion of carious lesions, in relation with raised Ba/Sr ratio, whereas consumption of marine products was scarce.  相似文献   
62.
While households are widely held to have existed as the fundamental building block of early agricultural villages, researchers have only a limited understanding of the local social and economic trajectory of Neolithic households. Expanding our archaeological understanding of the Neolithic household beyond architecture, settlement organization, and subsistence practices, in this paper we explore how gradual changes in mortuary practices at Tell Halula, Syria, help us to understand the process of household development around 7500–7300 Cal. BC. Drawing upon high-resolution mortuary data we consider the tempo and mechanisms of change and how these patterns help us understand the organization of the household. Material patterns including the increased use of burial objects, an increased frequency of the placement of burial objects among adults, and the differential use of burial objects between households. These represent subtle, yet observable, small-scale shifts in how social roles were redefined and materialized. We argue that these reflect a series of gradual changes that are suggestive of increased household autonomy and an increase in social segmentation within and between households. The Tell Halula data highlight elements of continuity and how household members adhered to a broadly shared physical and organizational framework of life. Data also illustrate how household members developed subtle means by which practices were personalization, and potentially, reflect growing means by which households and individuals were identified within these communities. Collectively, this research provides a detailed understanding of the grass-roots building blocks of Neolithic households over a short time frame and a more detailed understanding of the local social and economic trajectory of Neolithic households.  相似文献   
63.
This report presents the results of using NASA/JPL airborne synthetic aperture radar data (AIRSAR) to detect ancient Maya settlements beneath jungle canopy in Guatemala. AIRSAR stands out from previous applications of radar remote sensing in the Maya lowlands because of its canopy-penetrating capabilities. The authors offer an overview of the AIRSAR technology, followed by a case study in which the AIRSAR data receive testing in the field. Reconnaissance in the region around the Maya site of El Zotz led to the discovery of two new sites, including the medium-sized settlement of La Avispa. AIRSAR also aided archaeologists in detecting zones of residential settlement around the site core of El Zotz. This research will serve as a guide for future applications of radar remote sensing in Maya archaeology.  相似文献   
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65.
Teen employment is a very important socioeconomic phenomenon because of its consequences on human capital formation. We assess the relation between teen employment and poverty, education, and unemployment in the city of Rosario, using information from the 2010 Argentina Census disaggregated at census block level. We use two different spatial models: The spatial lag model (SLM) and a linear regression model with the spatial component filtered (filtering model, FM). Given the nature of the variables employed, multicollinearity is an issue. One of the techniques proposed in the literature to deal with multicollinearity problems is principal component regression (PCR). We develop an adaptation of such methodology to be used in the SLM. Both models are estimated using their traditional methodologies (instrumental variables for the SLM and OLS for the FM) and using PCR. Although results are similar between the two models, depending on the methodology used in the estimations they differ greatly. Under traditional methodologies estimations show high variability, instability, and contradictory outcomes, but under PCR, results behave according to the literature.  相似文献   
66.
This article aims to highlight the main arguments that sought to justify the incorporation and legitimization of Urban Regeneration in the urban policy agenda in Brazil. It shows how the convergence between different and even conflicting propositions related to urban development provided ideological support to the construction of discourses in which urban regeneration is portrayed as beneficial to society as a whole, and how recent international ideas on urban development were incorporated in urban policies of contemporary Brazil, considering our local socio-economic and political environment, planning tradition and regulatory frameworks. The focus will be on Rio de Janeiro and particularly São Paulo given the key role these two cities play in defining urban policy paradigms, guiding government agendas and exporting regulatory models to other parts of Brazil.  相似文献   
67.
Vallone, E.R., Vezzosi, R.I. & Cione, A.L. February 2017. First fossil fish (Teleostei, Siluriformes) from the Late Pleistocene of Santa Fe Province, Argentina. Alcheringa 00, 000–000. ISSN 0311-5518.

The record of fossil fish from the Pleistocene of Argentina is poor. Here we describe the first ichthyofauna from Late Pleistocene riverbank beds in the Salado River of Santa Fe Province, Argentina. The material consists of isolated pectoral and dorsal fin spines, together with skull fragments. Four species-level taxa referable to three families can be identified: Pterodoras granulosus (Doradidae), Pimelodus cf. maculatus and Pimelodus cf. albicans (Pimelodidae) and cf. Hypostomus sp. (Loricariidae). Specimens attributed to Pterodoras granulosus and Pimelodus maculatus represent a minimum age for origin of these taxa. The Salado River assemblage includes the richest record of Pleistocene catfishes yet documented from southern South America.

Evelyn Romina Vallone [] and Raúl Ignacio Vezzosi [], Laboratorio de Paleontología de Vertebrados, CICYTTP-CONICET, Materi y España, (3105) Diamante, Entre Ríos, Argentina; Alberto Luis Cione [], División Paleontología de Vertebrados. Museo de La Plata. Paseo del Bosque s/n, (1900) La Plata, Argentina.  相似文献   

68.
ABSTRACT

Chemical residues preserved in floors can be considered anthropic activity markers. In fact, residues are strictly related to the activities performed and reflect their spatial distribution. We present a synthesis of the work carried out over the last few decades in Mexico and Italy related to the study of chemical residues in floors. Residues can be identified performing specific chemical analyses both of plastered or earthen floors samples. We outline a methodological approach concerning the use of the markers of the activities to interpret food production and consumption in the archaeological record, based upon evidence from experimental, ethnoarchaeological and archaeological examples. Here we point out the advantages and problems of such an approach, mainly related to equifinality, of the use of spot tests and gas chromatography coupled with mass spectrometry techniques using examples from different sites in the world.  相似文献   
69.
This study shows the results of a multidisciplinary collaboration between the University of Calabria (Italy) and the National Autonomous University of Mexico (UNAM), about the compositional characterization of some mortars taken from Hagia Sophia in Istanbul (Turkey), one of the most important buildings in antiquity. Twenty samples of joint mortars were analysed by micro-chemical analyses (SEM-EDS), X-ray powder diffraction (XRPD), optical microscopy (OM) and transmission electron microscopy (TEM). The compositional study allowed us to define, with more detail, the construction phases of the fifth, sixth and tenth century. The petrographic analysis in thin section by optical microscopy showed four typologies of sands, used as aggregate, with specific compositional features. SEM-EDS analyses and TEM observations of the binder around the ceramic fragments of the aggregate showed the presence of different morphologies of single C-S-H compounds.  相似文献   
70.
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