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991.
992.
Food shortages, particularly of proteins, in Britain during the Second World War led to the suggestion re-surfacing that marine plankton might be harvested on an industrial scale first as human food, then turning to its potential use as a supplement to stock and poultry feed. The notion emanated in the United Kingdom from Sir John Graham Kerr, at Glasgow University. He encouraged Alister Hardy, at Hull, to develop the idea and the natural testing ground was the Clyde Sea Area (given the extensive history of plankton research at Millport). Unpublished documents from the archives of the Scottish Association for Marine Science shed new light on the interactions behind the scenes of this project between Kerr, Hardy and the Millport Marine Station's then director, Richard Elmhirst. Elmhirst, who was sceptical about the feasibility of the plan from the outset, went along with it; not least as a way of attracting welcome research funding during lean times but also, doubtless, regarding it as his patriotic duty in case the proposal proved worthwhile.  相似文献   
993.
Archaeological fish bones reveal increases in marine fish utilisation in Northern and Western Europe beginning in the 10th and 11th centuries AD. We use stable isotope signatures from 300 archaeological cod (Gadus morhua) bones to determine whether this sea fishing revolution resulted from increased local fishing or the introduction of preserved fish transported from distant waters such as Arctic Norway, Iceland and/or the Northern Isles of Scotland (Orkney and Shetland). Results from 12 settlements in England and Flanders (Belgium) indicate that catches were initially local. Between the 9th and 12th centuries most bones represented fish from the southern North Sea. Conversely, by the 13th to 14th centuries demand was increasingly met through long distance transport – signalling the onset of the globalisation of commercial fisheries and suggesting that cities such as London quickly outgrew the capacity of local fish supplies.  相似文献   
994.
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996.
Michael Schiffer’s theoretical and methodological contributions to archaeology are substantial. For the last two decades, Schiffer has become increasingly interested in the history of electrical technology, including portable radios, electric automobiles, eighteenth-century electrostatic technology, and, most recently, nineteenth-century electric light and power systems. Schiffer has long held a behavioral view, which focuses analytical attention on interactions between humans and material things, including complex technological systems (CTSs). For Schiffer, two key aspects of the evolution of CTSs are stimulated variation, defined as an increase in invention resulting from changing selective conditions, and cascading, defined as sequential spurts of invention that occur through the recognition of emergent performance problems in a CTS. To attain maximum usefulness, these concepts should be placed in a modern evolutionary framework that correctly identifies, and does not oversell, the role played by cultural selection. Research on individual and social learning provides the critical link between Schiffer’s stimulated variation and cascade models and the diffusion of CTSs.  相似文献   
997.
998.
This paper notes the adoption of digital photography as a primary recording means within archaeology, and reviews some issues and problems that this presents. Particular attention is given to the problems of recording high-contrast scenes in archaeology and high dynamic range imaging using multiple exposures is suggested as a means of providing an archive of high-contrast scenes that can later be tone-mapped to provide a variety of visualisations. Exposure fusion is also considered, although it is noted that this has some disadvantages. Three case studies are then presented: (1) a very high-contrast photograph taken from within a rock-cut tomb at Cala Morell, Menorca, (2) an archaeological test pitting exercise requiring rapid acquisition of photographic records in challenging circumstances and (3) legacy material consisting of three differently exposed colour positive (slide) photographs of the same scene. In each case, high dynamic range (HDR) methods are shown to significantly aid the generation of a high-quality illustrative record photograph, and it is concluded that HDR imaging could serve an effective role in archaeological photographic recording, although there remain problems of archiving and distributing HDR radiance map data.  相似文献   
999.
1000.
Much of the excitement generated in Britain since 2007 by the York Archaeological Trust’s excavations of the city’s Hungate neighborhood, which Benjamin Seebohm Rowntree characterized as a “slum” in his pioneering poverty survey of 1901, derives from the unexpected volume and variety of material evidence uncovered about life in a poor community within a modern industrial city. Such material evidence and its often uncertain relationships to other historical data can enhance analysis by complicating understanding of the past, rather than echoing conventional wisdom. Findings from Hungate can thus contribute to nuanced understandings of urban social disadvantage not only at the neighborhood level in this one particular British city, but at the larger scales of analysis that encompass the growth of cities and interacting urban regions in Britain and around the world during the nineteenth and twentieth centuries. These understandings have contemporary relevance for a world in which over half of humanity now lives in urban areas, as misconceptions about “slums” continue to undermine efforts to reduce urban inequality.  相似文献   
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