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The remains of Henry V's flagship, the Grace Dieu, currently lie buried within the inter-tidal sediments of the River Hamble (S. England). Previous archaeological investigations have been hindered by difficult excavation conditions resulting in a poor understanding of the dimensions, shape and degradation state of the hull's deeper structure. This study therefore aimed to image, characterize and reconstruct the buried remains of this vessel using a high-resolution 3D acoustic sub-bottom Chirp system with RTK-GPS positioning capability. The accurate navigation and high-resolution data that were acquired enabled the construction of a full 3D image of the site that not only identified the remains of the wooden hull, but also features buried within it. In addition, the degradation state of these buried wooden remains were investigated by calculating reflection coefficients while a hypothetical larger reconstruction of the Grace Dieu's hull was achieved, through the use of the ShipShape ship design software package.  相似文献   
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Neutron diffraction (ND) analyses of ancient metals show that this method is capable of detecting differences in the inner composition and microstructure of ancient metal objects. Here, ND measurements were conducted on two ‘eye shaped’ axes from the end of the 3rd-beginning of the 2nd millennium BC. The objects were excavated from the ancient cemetery of ‘Enot Shuni' Israel; one is made of bronze and the other of silver. Both artefacts are rare finds, with the silver axe unique in the archaeology of Israel, and therefore had to be analysed locally. For that purpose, a newly assembled diffractometer (KARL) at the IRR-1 of the Nuclear Research Centre (Soreq, Israel) was used. ND measurement on the bronze axe revealed the existence of an α-phase with a range of Cu/Sn ratios (Cu–Sn solid solutions) and some amount of a δ-phase (intermetallic compound of Cu and Sn). The silver axe ND pattern shows the existence of an α-phase (Ag–Cu solid solution) and some amount of copper metal. Our ND data are discussed in comparison with XRF surface measurements and thermal neutron radiography. The results are shedding more light on the in-depth material composition profile, as well as on the objects’ structural and compositional affinities, and help to better understand the production processes and assist in conservation decisions.  相似文献   
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A paucity of archaeological remains of Atlantic salmon in Northeast North America has been cited as evidence that the species may have been present in the region only during and after the Little Ice Age (ca. 1450–1850 AD), one of coldest periods of the Holocene. However, significant problems of preservation, recovery and identification remain. Here, improved methods of identification use vertebra structure to distinguish salmon from trout, and strontium/calcium ratios to differentiate sea-run from landlocked salmon. In addition to the Little Ice Age, Atlantic salmon is identified in tightly dated contexts at 7000–6500 and 3500–3000 calendar years BP, during climate periods that were comparatively warm and wet.  相似文献   
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Martin  Jay 《History and theory》2009,48(1):76-84
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Results of analyses of the photoperiod response gene (PPD-H1) and simple sequence repeats (SSRs) in modern landraces of cultivated barley were used as evidence for the mechanism of agricultural spread in Neolithic Europe. In particular, we explored the usefulness of considering adaptive genes as indicators of past selective pressures acting on crops, during their spread through Europe. In some areas, such as the Alpine region, Britain and Scandinavia, we have evidence to suggest that the adaptation of crops to certain climatic conditions may have contributed to the timing of agricultural spread. At the northern fringes of Europe, and in higher altitude locations in central Europe, the introduction of more suitably adapted cereals may have facilitated successful agriculture to trigger agricultural expansion. This research opens up the possibility of investigating other genetic adaptations to climate, which would permit a fuller evaluation of the relative contributions of climate/crop and forager/farmer interactions in the process of agricultural spread.  相似文献   
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