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61.
A reference sample of dental and oral nonmetric traits should represent its biological population from which it stems. The presence of individuals born at different times, different regions, and separate countries in the Coimbra-identified cranial collections provides the test of whether this sample reflects the biological continuity of this Portuguese sample among the late modern (early industrialization, nineteenth century) to early contemporary (early demographic transition, first half of the twentieth century) population of this region of central Portugal. The Coimbra collections were scored for 61 traits using methodology by Hauser and De Stefano (1989), Turner et al. (1991), Scott and Turner (1997), Irish (1998), and Marado and Silva (2016). The 600 individuals in the sample were divided by generation, region, and nationality. Their phenetic diversity was tested with principal component analysis and with the mean measure of divergence statistic. The proximity between the subsamples was generalized, and it mimicked previous genetic marker results. Some small subsamples hindered conclusions; nevertheless, this Coimbra sample is considered a reliable dental reference sample for the Portuguese late modern/early contemporary population.  相似文献   
62.
Elemental analyses and microstructural studies of historical metal artifacts provide researchers with invaluable and priceless information about metal extraction technology and the procedure of creating artifacts. In addition, the information is helpful for knowing about the metallurgical processes of the artifacts. This study was conducted by a microscopic examination and elemental analyses of seven Sasanian silver coins preserved in the Sistan Anthropology Museum, Iran. For the purpose of this study, three methods were employed: first, the proton induced X-ray emission microanalysis (micro-PIXE), to determine the main and trace elements of the coins; second, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS), to perform elemental analysis to identify impurities of the metal; and third, microstructural analysis of the coins which was carried out with an optical microscope (OM). The elemental analyses identified Ca, Cu, Ag, Au, and Pb in the coins. The high quantity of Ag in samples validated the application of advanced and accurate cupellation technology for refining silver and separating impurities from raw ore. The gold concentration in the coins indicated the use of non-galena ore for silver extraction. Additionally, the microstructural analyses of samples pointed to the application of thermo-mechanical processes on coins.  相似文献   
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The aim of this work is to characterize the original concrete from Roman buildings for public spectacles, theatre and amphitheatre, from Emerita Augusta, Mérida, Spain. An advanced knowledge of the Roman concrete composition is required for a reliable restoration and preservation of these ancient monuments. The concrete was studied through mineralogical (optical polarized microscopy and X-ray diffraction) and petrophysical (bulk and real density, open porosity to water and Hg, mechanical strength and ultrasonic velocity) analyses. With this work, it is possible to fill the gap that exists in this field and the characterization of the materials used in the Roman concrete from these two buildings, never previously studied, despite the significance of this archaeological ensemble, declared a World Heritage Site by UNESCO in 1993. The results allowed us to determine the composition of the Roman concrete and to infer the provenance of the aggregates used in these monuments.  相似文献   
65.
Sex estimation of skeletal remains is one of the major components of forensic identification of unknown individuals. Teeth are a potential source of information on sex and are often recovered in archaeological or forensic contexts due to their post-mortem longevity. Currently, there is limited data on dental sexual dimorphism of archaeological populations from Iran. This paper represents the first study to provide a dental sex estimation method for Iron Age populations. The current study was conducted on the skeletal remains of 143 adults from two Iron Age populations in close temporal and geographic proximity in the Solduz Valley (West Azerbaijan Province of Iran). Mesiodistal and buccolingual cervical measurements of 1334 maxillary and mandibular teeth were used to investigate the degree of sexual dimorphism in permanent dentition and to assess their applicability in sex estimation. Data was analysed using discriminant function analysis (SPSS 23), and posterior probabilities were calculated for all produced formulae. The results showed that incisors and canines were the most sexually dimorphic teeth, providing percentages of correct sex classification between 86.4 and 100 % depending on the measurement used. The combination of canines and other teeth improved significantly the level of correct sex classification. The highest percentages of sex classification were obtained by the combination of canines and incisors (100 %) and canines and molars (92.3 %). The present study provided the first reference standards for sex estimation using odontometric data in an Iranian archaeological population. Cervical measurements were found to be of value for sex assessment, and the method presented here can be a useful tool for establishing accurate demographic data from skeletal remains of the Iron Age from Iran.  相似文献   
66.
Determining hand laterality during human evolution is important in order to identify brain hemispheric lateralization for motor tasks and, indirectly, to gain information on the complex cognitive functions of the human brain. In this paper, we present a new method for inferring handedness from lithic evidence. The study is based on an analysis of the scatter patterns of lithic remains from stone-knapping episodes. An experimental programme was carried out by 14 knappers (eight right-handed and six left-handed), ranging from individuals that had never even struck two pebbles together to individuals who were quite familiar with prehistoric tools and had some degree of practice. The results of the experiment show that the material scatter patterns of right- and left-handed knappers at group level are different, but they do overlap at certain intervals. At the individual level, the probability of falsely ascribing left- and right-handedness has also been estimated. In addition, we have adapted this method to be applied to the archaeological record. In this case, only well-preserved knapping events with no post-depositional alterations can be used to assign left- or right-handed knappers, with the former being more reliably detected than the latter.  相似文献   
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Cleantech has emerged in the last decade as a major new investment sector at the forefront of the green economy. It responds to the need for innovative technologies to combat the impact of global environmental, climate and resource trends. Focusing on the cleantech sector, this article explores the central importance of relationality within the financial domain of the green economy. The central aim of this article is to deepen understandings of the operation of cleantech investment by examining the decision‐making processes of cleantech actors, how these are influenced by (and influence) cleantech investment networks, and the relationships between these factors and the macro‐level drivers and discourses focused on the cleantech sector. A relational economic geography approach is used in conjunction with other frameworks (spanning the cultural, structural and actor‐network dimensions of cleantech investment) to investigate: how cleantech investors define the sector; the macro‐ and micro‐level drivers of cleantech investment; and how cleantech networks form and operate to create and disseminate cleantech discourses and to generate the mutual trust and information sharing needed to secure cleantech investments. In so doing, the article seeks to shed greater light on the micro‐level processes contributing to the creation and growth of cleantech investment markets as an essential catalyst and component of the green economy.  相似文献   
69.
Abstract

The prehistoric development of food storage represents a major evolutionary transition, one potentially more important than the initial domestication of plants. Researchers, however, have yet to really deal with some of the critical practical questions related to the materiality of food storage and decision-making. Drawing upon experimental research this paper seeks to identify and model some of the critical interconnections between anticipated food loss due to spoilage, storage decision-making and the need for people to store food for multiple years. Building on this foundation, and echoing ethnographic, ethnoarchaeological and archaeological research, this study argues that the concept of storage and surplus is underdeveloped and that in many cases the storage practices of prehistoric sedentary people do not reflect a food surplus so much as normal storage. Turning to a case study of changing Near Eastern Neolithic grain storage practices, this research argues that from the Natufian through Neolithic periods people increasingly relied upon cultivated domesticated plants and food storage. This required people to expand their use of pre-existing technology, such as plaster for lining storage features, to store sufficient amounts of food to overcome seasonal shortages, potential crop failures and minimise food spoilage due to a range of biological agents. Tracking shifts through time, the results of this study suggest that it is only with increased scale of food storage in the later stages of the Neolithic that we may see a materialization of a food surplus.  相似文献   
70.
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