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21.
Some radiocarbon dates for ancient Egypt have been significantly offset from the established historical chronology (see Bonani et al., 2001). In this paper, short-lived plant species collected in Egypt between 1700 and 1900 AD were used to investigate the possibility that the radiocarbon record had been influenced by reservoir effects. AMS radiocarbon measurements were made on 66 known-age samples, resulting in an average offset from expected values of 19 years. The implications of this minor discrepancy on the likelihood of a reservoir process are discussed, and the agreement of the data with recent models of radiocarbon seasonality is also considered.  相似文献   
22.
The origins of raw glass used to fashion Mycenaean beads were explored using trace elements analyzed by laser ablation ICP-TOFMS. The use of this minimally destructive technique for the in-situ analysis of these beads was ideal given that the material is exceedingly rare and thus too sensitive to make use of traditional micro-sampling (e.g., by scalpel). A wide range of trace elements were measured to compare these Greek glasses to other Late Bronze Age glass coming from Egypt and Mesopotamia. Of the eleven beads analyzed, four blue glasses colored with cobalt and two blue/green glasses colored with copper have trace element compositions consistent with an Egyptian origin of manufacture. The other five of the glasses, all colored with copper, were found to conform to the composition of Mesopotamian glass. These data are the first to demonstrate direct and clear evidence for the trade of raw glass to the Mycenaean states.  相似文献   
23.
Excavations at Cladh Hallan, a Bronze Age-Iron Age settlement on South Uist in the Outer Hebrides off the west coast of Scotland, revealed the skeletons of two adults, a sub-adult and a child buried beneath the foundations of three roundhouses. Osteological and isotopic evidence has shown that the male adult skeleton is a composite made up of parts of at least three different individuals. To test the hypothesis that the female skeleton was also a composite we examined ancient DNA from four of its components: the skull, mandible, right humerus and right femur. Seven polymerase chain reactions (PCRs) were attempted, these covering positions 15,996–16,420, 16–132 and 232–368 of the mitochondrial DNA hypervariable I and II regions. Three PCRs were successful for each sample and a total of 55 sequences were obtained from the cloned products. After exclusion of possible contaminating sequences, the remaining 34 were compared. It was concluded that the mandible, humerus and femur come from different individuals. Insufficient data were obtained to draw conclusions regarding the origin of the skull. The presence of two composite skeletons at Cladh Hallan indicates that the merging of identities may have been a deliberate act, perhaps designed to amalgamate different ancestries into a single lineage.  相似文献   
24.
Optical Coherence Tomography (OCT) is a non-invasive subsurface 3D imaging technique based on the Michelson interferometer. The non-invasive nature of OCT and its speed of acquisition makes it possible to image large volumes of intact objects to yield a complete overview of the microstructure. The production methods for ancient Egyptian faience were first investigated using scanning electron microscopy (SEM) imaging of the microstructure in polished sections and microprobe analysis of the composition of the glass phases. These studies were based on original Egyptian faience objects and laboratory reproductions of faience beads made using three different production methods. The microstructure of the same laboratory samples and the Egyptian faience objects from the British Museum Research Laboratory Collection are re-examined using OCT. It is found that OCT virtual cross-section images can be used to group ancient faience objects into three categories on the basis of the morphology of the surface glaze layer and the glaze/core interaction layer. The OCT images correspond well with SEM images of polished sections of ancient faience objects and laboratory reproductions. The virtual cross-sections produced by OCT are somewhat limited by the penetration depth, which is affected by the high absorption coefficient of the material and, therefore, cannot always provide information on the presence or absence of interparticle glass that binds together the quartz particles in the core. Nevertheless, the top two layers are well imaged and since OCT images can be obtained rapidly and without the necessity of removing a sample, the method can be applied to a very much wider range of ancient faience objects than is possible by SEM examination of polished cross-sections. In summary, this paper examines to what extent OCT can assist the investigation of the production techniques of ancient Egyptian faience.  相似文献   
25.
For five decades it has been generally accepted that reserpine, an antihypertensive and antipsychotic drug, causes depression. The discovery that reserpine depletes brain monoamines was an important factor in the development of the monoamine hypothesis of depression, and it continues to be widely cited in support of this hypothesis. The present paper argues that, contrary to prevailing belief, reserpine is not depressogenic. The reason for perpetuation of this myth is reluctance to discard the monoamine hypothesis. This hypothesis ushered the modern biochemical paradigm into psychiatry and is still of great importance. It serves as a heuristic to guide research, it enhances psychiatry’s prestige, and it helps to validate and promote drug therapy for depression and other mental disorders.  相似文献   
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Since being excavated in 2003, the skull of LB1 (the holotype of Homo floresiensis) has been given many faces, though the details regarding how each was accomplished are typically few. Here we detail our application of known, and verified, relationships between the skull and soft tissues of anatomically modern humans to produce an evidence-based facial approximation of LB1. We then compare our results to nine pre-existing LB1 faces using geometric morphometrics. These analyses suggest our facial approximation differs in proportional facial width, upper lip height and nasal morphology. Some of these differences are likely due to a different interpretation of taphonomic and excavation damage, application of different 'forensic' methods and/or an idiosyncratic incorporation of aspects of non-human primate morphology. Other differences, and in particular upper lip height, are less justifiable in relation to the skeletal evidence.  相似文献   
28.
This paper presents 19 AMS radiocarbon dates from nine pre-Hispanic Caribbean (Taíno/Lucayan) wooden sculptures in the British Museum collections, provenanced to Jamaica, Hispaniola and the Bahamas. Together with strontium isotope results and wood and resin identifications, these data build a material and chronological context for some of the most recognised examples of Taíno art – from duhos (ceremonial seats) and cemís (free standing depictions of deities, ancestors and spirits) to canopied stands used to hold hallucinogenic drugs during the cohoba ceremony. Each sculpture widens our understanding of Caribbean carving traditions, stylistic variation, chronologies and material resource utilisation. A group of three sculptures recovered from Carpenters Mountains, Jamaica, carved by AD 1300 and brought together as a ceremonial ‘set’, each appear to have had their inlays renewed over a century later, suggesting long-term use. Three key examples of the main Caribbean duho categories (high-back, low-back and extended), provide insights into the diversity of styles present in the region post-AD 1100. The British Museum's corpus enables an exploration of regional styles, and potentially the work of individual artists.  相似文献   
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Abstract. This paper examines the relationship between nationalist movements and minority languages, with particular emphasis on examples from Britain and Ireland. This relationship is less straightforward than often assumed, and the media's role in it is particularly complex. The varying political uses of minority language broadcasting are discussed, along with the implications of the separation between cultural and political nationalism. The notion of the routine banality of daily broadcasting is used to indicate how such broadcasting can work against nationalist mobilisation. Finally, Ireland is examined in the light of the previous discussion in order to offer an explanation of why it was so far behind many other areas in the provision of minority language broadcasting.  相似文献   
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