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61.
Andrew A. Meharg Kevin J. Edwards J. Edward Schofield Andrea Raab Joerg Feldmann Annette Moran Charlotte L. Bryant Barry Thornton Julian J.C. Dawson 《Journal of archaeological science》2012,39(3):717-727
Tin, as a constituent of bronze, was central to the technological development of early societies, but cassiterite (SnO2) deposits were scarce and located distantly from the centres of Mediterranean civilizations. As Britain had the largest workable ore deposits in the ancient Western world, this has led to much historical speculation and myth regarding the long-distance trading of tin from the Bronze Age onwards. Here we establish the first detailed chronology for tin, along with lead and copper deposition, into undisturbed ombrotrophic (rain-fed) peat bogs located at Bodmin Moor and Dartmoor in the centre of the British tin ore fields. Sustained elevated tin deposition is demonstrated clearly, with peaks occurring at 100–400 and 700–1000 calendar years AD – contemporaneous with the Roman and Anglo-Saxon periods respectively. While pre-Roman Iron Age tin exploitation undoubtedly took place, it was on a scale that did not result in convincingly enhanced deposition of the metal. The deposition of lead in the peat record provides evidence of a pre-Roman metal-based economy in southwest Britain. Emerging in the 4th century BC, this was centred on copper and lead ore processing that expanded exponentially and then collapsed upon Roman colonization during the 1st century AD. 相似文献
62.
Magnetometry has been little used on Arctic archaeological sites, but has great potential to help us understand site structure by identifying buried features and providing additional detail about the construction and use of visible surface features. In the Arctic environment, magnetometer surveys have to deal with the effects of permafrost activity on soils and the potential influence of glacial erratics of varying geological composition. Here, we present the results of magnetometer surveys of a non-cultural site with periglacial features and two archaeological sites located in the Canadian low Arctic. Despite considerable “noise” apparently caused by igneous erratics, the surveys successfully identified several frost features and a range of archaeological feature types. They also appear to have located buried archaeological features and identified activity areas within some dwellings. These preliminary results suggest that the technique is worth pursuing on northern sites. 相似文献
63.
Matt McDonald 《Australian journal of political science》2011,46(2):281-295
In the lead-up to the Australian federal election in 2010, both major political parties represented the ‘unauthorised’ arrival of asylum-seekers as a security issue. This article explores the dynamics of this resecuritization of asylum in Australia, suggesting the case has important implications for both the securitization framework and Australia's treatment of asylum-seekers. The relationship between securitization and calls for an open debate about asylum-seekers challenges the securitization framework's normative claims about political debate and deliberation as a progressive development illustrative of desecuritization (the removal of issues from the security agenda). This case also illustrates that without political leadership to engage with the social and cultural context that allows the securitization of asylum to resonate with large segments of the Australian population, the exploitation of this issue for short-term political gain will continue. 相似文献
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Gordon Morgan Holmes, MD, MRCP was an Irish born neurologist who received his medical education at Trinity College, Dublin, Ireland. He was trained in neuroanatomy and neuropathology at the Senckenberg Institute, Frankfort-Am-Main by Ludwig Edinger. He then returned to serve as a Registrar (House Officer) mentored by Richard Gowers and John Hughlings Jackson at the National Hospital, Queen Square, London. He collaborated with Thomas Granger Stewart in describing the loss of recoil in patients with cerebellar hemispheric tumors in 1904. Volunteering in 1914 for frontline hospital duty, he examined soldiers who had injuries to their occipital area causing hypotonia, dysmetria, staggering gait, and falling to the side ipsilateral to their injured cerebellar hemisphere. Holmes discovered that increasing the pace of the finger-nose manuever and applying slight resistance to a moving limb attenuated the dysmetria. Continuing observation of these patients afforded him to describe the evolution of their injuries to include increasing tremor and decreasing hypotonia. Holmes first attached levers to the limbs of hispatients to record their movements on a moving smoked paper kymograph. In 1939 he published photograh tracings made by low mass minature light bulbs attached to ataxic limbs that showed thehpometira and hypometria of their movements ipsilateral to their damaged cerebellar lobes. Holmes made sigficant contributions to understanding of the physiology of the human cerebellum. 相似文献
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Edward A. Freeman 《考古杂志》2013,170(1):136-148
Mathematical ability and good architecture have gone together in several notable instances. Euclid's ‘Elements’ has been one of the great formative works in the history of mankind and it would be reasonable to expect that it would have some influence upon architecture. It was practically unknown in the west until translated from the Arabic into Latin by Adelard of Bath about 1120. This translation had an immense impact on medieval thought and it is arguable that it was a major factor in the greater accuracy in the setting out of buildings that began about that time. The question of skew chancels is specially considered. But the main reason for holding the translation to have had a big influence upon medieval architecture is the strong tradition among Freemasons that ‘the worthy clerk Euclid’ was the founder of their craft. 相似文献
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Edward A. Freeman 《考古杂志》2013,170(1):177-195
An investigation of almost all recognized Anglo-Saxon churches has been undertaken to scrutinize carefully their quoins, pilaster strips and arch jambs, where these are readily visible for detailed study from ground level. The geological orientations within the stones in these structures have been recorded where they are clearly discernible. The stones, irrespective of their size and shape, display in all visible instances distinct patterns and styles of Anglo-Saxon construction. A simple nomenclature is proposed to identify the bedding orientations of the stones. These patterns of stone orientation, particularly when applied together with an understanding of the different rock lithologies, can be used to enable the structural portions of Anglo-Saxon church buildings to be identified with greater precision. 相似文献
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