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961.
Palygorskite is a rare clay mineral used by the ancient Mayas for fabricating the Maya blue pigment and for other purposes. It seems to have been obtained from a restricted area in the Yucatán peninsula where important archaeological sites are found. Geological samples from different localities in this area show a high content in palygorskite, indicating that this clay is widespread in Yucatán. Combining structural, morphological, compositional and geochemical methods, we analysed the common characteristics of Yucatecan palygorskites, and compared them with palygorskites from other origins around the world. These results can be used for defining a fingerprint of Yucatecan palygorskite to be used in provenance studies of archaeological artefacts, in particular the Maya blue pigment.  相似文献   
962.
The pigments, binders and execution techniques used by the Nasrids (1238–1492) to polychrome carpentry in the Hall of the Mexuar Palace at the Alhambra (Granada, Spain) were studied using optical microscopy, scanning electron microscopy with EDX analysis, selective staining techniques and gas chromatography – mass spectrometry. This pioneering investigation presents the first results of a research project devoted to filling gaps in the knowledge of Nasrid art, traditionally approached by stylistic studies. Moreover, it is essential for the polychromy conservation of the studied artworks, and will help to clarify historical and painting uncertainties in the Alhambra monument. The palette consists of a limited range of colours: white (lead‐base pigment), red (cinnabar and red lead), blue (lapis lazuli), black (carbon‐based) and false gold (golden tin). Tempera grassa was the painting technique identified. Two types of grounds were used: (i) gypsum in calligraphy decoration for the false gold technique, and (ii) synthetic minium in geometric drawings in carpentry. Organic insulating layers of linseed oil were used between paint strata. Artists applied synthetic minium to protect the wood (Juglans regia and conifer) against attack by xylophages. To lighten the surface darkened by this ground layer, powdered tin was added to achieve a metallic lustre.  相似文献   
963.
964.
发现区域聚落形态是一项重要的研究,也是令人振奋、挑战智慧的工作。区域考古学看来总是会产生新的、始料未及的洞见,它具有持久的价值,并对不同规模的其他研究是基础性的,而且它也是(或者说应该是)遗产保护的根本所在。  相似文献   
965.
Two concentrations of animal bones, almost exclusively from small mammals and wild birds, were found within the destruction debris of a Roman bath complex in Sagalassos (SW Turkey). The overall species spectrum, skeletal element representation, fragmentation and preservation condition of the bones indicate that they represent the prey remains of a large nocturnal avian predator, more precisely the eagle owl (Bubo bubo). Differences in skeletal element representation and in prey species' spectrum show that the two bone clusters derive from pellets deposited near a nest site and a roost site, respectively. Radiocarbon dates obtained from the bones indicate that eagle owls lived in the collapsing bath complex during the second half of the 6th to the beginning of the 7th century AD, before the final abandonment of the town. The MNI of the prey animals found at the nest site, confronted with the daily dietary needs of a female eagle owl and its young, indicates repetitive use of the same place during several years. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
966.
A scapula malformation is described in two burials from the site of the late medieval Dominican friary at Ipswich, UK. The changes appear most consistent with primary scapular neck dysplasia. One of the burials also showed clear signs of leprosy. The burials are of lay benefactors of the friary. The Ipswich Dominican friary had no known function as a leprosy hospital. Finding of burials of lepers other than in burial grounds of leprosaria is highly unusual for medieval England. Scapular neck dysplasia has a strong genetic component in its aetiology. This, coupled with its rarity, suggests a close genetic link between the two burials. The findings suggest that in this case, family ties with the friary overrode the normal medieval custom of interring lepers in leprosy hospitals. This illustrates that even rare skeletal variants may convey useful biocultural information about past populations. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
967.
Skeletal weight and/or weight of the different bones of the human skeleton are currently used in a wide range of applications such as archaeological cremations and forensics. Still, few reference values are available that compare the mean weights for the different skeletal parts. In this paper we present new reference values for total skeletal weight, including the weight of the different skeletal bones based on a modern Portuguese Identified Skeletal Collection (CEI) curated in the Museum of Anthropology of the University of Coimbra (Portugal). The mean weight of the entire skeleton for the CEI pooled sample is 3323.8 ± 779.6 g. Sex and age differences were investigated. As expected, males display heavier bones, at a statistically significant level. The mean weight of the male skeletons is 3850 g, and 2797.6 g for the female sample. Age differences were found, especially for the female samples in the 29–39 versus 50–59 and/or >60 age groups, probably as a consequence of age‐related bone loss in post‐menopausal women. For the male sample, no clear age‐related trend was observed but for the unexpected result that the second highest bone weight recorded is in the oldest age group (>60 years). This could result from high mechanical loadings and thus greater bone robusticy and amount of cortical bone. The percentage of weight of the different parts of the skeleton was also calculated. These new values can be quite useful in the study of very fragmentary and/or commingled human remains, recovered from historic or forensic contexts, since the complete identification, by side, of the remains is not necessary. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
968.
The macroevolutionary approach in archaeology represents the most recent example in a long tradition of applying principles of biological evolution to the study of culture change. Archaeologists working within this paradigm see macroevolutionary theory as an effective response to the shortcomings of neo-Darwinian biological evolution for studying cultural evolution. Rather than operating at the level of individual traits, macroevolutionary archaeologists emphasize the role of hierarchical processes in culture change. While neo-Darwinian archaeologists disavow any element of human intent in culture change, to macroevolutionary archaeologists human agency is a key component of cultural evolution that allows cultures to respond to pressures more quickly and with greater degree of flexibility and directedness than found in biological evolution. Major culture change, when it happens, is likely to be rapid, even revolutionary, with periods of rapid change separated by periods of relative stasis of actively maintained stability. The emergence of Neolithic cultures has long been recognized as one of two periods of major revolutionary culture change in human prehistory. Here I examine the record for the Near East, tracing the empirical record for the origin of agriculture in this region, as well as other demographic, social, and ideological components of Neolithic emergence. While the empirical record from the Near East subscribes in a general way to basic principles of macroevolutionary theory, cultural evolution cannot be understood through appeal to principles of biological evolution alone, whether based in macroevolutionary theory or neo-Darwinianism. Instead, the key role of human agency in culture change distinguishes cultural evolution from biological evolution and requires a more pluralistic and less doctrinaire appeal to multiple models of change based in both the biological and social sciences.  相似文献   
969.
Petroleum-bearing fluid inclusions emit fluorescent light when excited with UV or visible light. The fluorescence decay time of the emission is dependent upon the wavelengths of the excitation and emission light, and the chemical composition of the petroleum oil. In general heavy oils have short lifetimes, whereas the emission from light oils is much longer lived. One can thus use plots of the fluorescence lifetime versus emission wavelength ( τ – λ plots), to show even subtle changes in the chemical composition of the entrapped oil. As a consequence, these τ – λ plots can be used for fluid inclusion research to discriminate different oil populations in situ . In particular, it is demonstrated that τ – λ plots discriminate two sets of inclusion oils in each of four North Atlantic basins [Jeanne d'Arc Basin (Newfoundland), Porcupine Basin (Ireland), Clair field West of Shetland (UK) and Kangerlussuaq Basin (East Greenland)] where multistage oil charge is inferred from other geological evidence.  相似文献   
970.
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