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Tim Kinnaird Tom Dawson David Sanderson Derek Hamilton Alan Cresswell Rebecca Rennell 《The Journal of Island and Coastal Archaeology》2019,14(1):46-60
A high-resolution chronostratigraphy has been established for an eroding Atlantic round house at Sloc Sàbhaidh (North Uist, Scotland), combining detailed OSL profiling and dating of sediments encompassing the main bracketing events associated with the monument, radiocarbon AMS dates on bone recovered from excavated features and fills within it, and TL dates on pottery and burnt clay. Concordant OSL and radiocarbon evidence place construction of the wheelhouse in the first to second centuries AD, contemporary with dates from the primary occupation. Beneath the wheelhouse, clay deposits containing burnt material, attest to cultural activity in vicinity to the monument in the preceding second to first centuries BC. At a later date, the southern wall collapsed, was rebuilt, and the interior spaces to the monument re-structured. The chronology for the later horizons identified from the sediment luminescence dates extends to the second half of the first millennium AD, which goes beyond the range of the radiocarbon dates obtained. The data from ceramics encompass both periods. The juxtaposition of the dating evidence is discussed relative to short and longer chronologies for this Iron Age monument. Corollaries of this research are the implications that based on the long chronology, some of the ecofacts (bone) appear to be residual, and that the temporal duration of Hebridean Coarse Ware may extend into the second half of the first millennium AD. 相似文献
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In this paper we ask how a shrinking city responds when faced with a perforated urban fabric. Drawing on Manchester's response to its perforated eastern flank —and informed by a parallel study of Leipzig—we use the city's current approach to critique urban regeneration policy in England. Urban renaissance holds out the promise of delivering more sustainable—that is more compact, more inclusive and more equitable—cities. However, the Manchester study demonstrated that the attempt to stem population loss from the city is at best fragile, despite a raft of policies now in place to support urban renaissance in England. It is argued here that Manchester like Leipzig is likely to face an ongoing battle to attract residents back from their suburban hinterlands. This is especially true of the family market that we identify as being an important element for long-term sustainable population growth in both cities. We use the case of New East Manchester to consider how discourses linked to urban renaissance—particularly those that link urbanism with greater densities—rule out some of the options available to Leipzig, namely, managing the long-term perforation of the city. We demonstrate that while Manchester is inevitably committed to the urban renaissance agenda, in practice New East Manchester demonstrates a far more pragmatic—but equally unavoidable—approach. This we attribute to the gap between renaissance and regeneration described by Amin et al. (Cities for the Many Not for the Few. Bristol: Policy Press, 2000) who define the former as urbanism for the middle class and the latter as urbanism for the working class. While this opportunistic approach may ultimately succeed in producing development on the ground, it will not address the fundamental, and chronic, problem; the combination of push and pull that sees families relocating to suburban areas. Thus, if existing communities in East Manchester are to have their area buoyed up—or sustained—by incomers, and especially families, with greater levels of social capital and higher incomes urban policy in England will have to be challenged. 相似文献
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Alan M. W. Porter 《International Journal of Osteoarchaeology》1995,5(4):305-323
The femur remains an important bone in palaeoanthropology and this paper reports various analyses of measurements taken from long-cassette radiographs of adult femurs of a reference population from the south of England (n=81, males 33, females 48). Discriminant analysis confirmed that the male femur is usually larger than the female femur, and that a femur may be sexed with some confidence. Discriminant scores have been derived to permit estimates to be made, from the whole or a part of a femur, of the probability of the male gender. Outcomes from a principal component analysis suggest: that the female proximal femur is a morphological unit; that neck length and shaft length are dissociated and there is no common factor representing linearity; and that the male bicondylar width is anomalous, a finding that is confirmed by other analyses. An estimate of the robusticity of the complete female, but not male, bone may sometimes be made from a proximal fragment. The robusticity of the complete bone may be made confidently from the shaft for both genders. The two width variables relating to a distal fragment cannot be used to predict the robusticity of the complete bone for either gender. A method of defining the position of the waist in terms of displacement in deciles down the shaft is described. The position of the waist seems to have a bimodal distribution. The positive association between age and distal displacement may be due to remoulding of the shaft with age or to a cohort (generational) effect. There is a weak correlation between a small neck–shaft angle and the distal displacement of the waist, two archaic phenotypic traits. Ten statements in the literature relating to the femur have been examined and tested; six are confirmed and four are unconfirmed, and it is suggested that there is a need for further studies relating to the morphology of the femur. 相似文献
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This review examines the history of discoveries that contributed to development of the dopamine hypothesis of schizophrenia. The origin of the hypothesis is traced to the recognition that neuroleptic drugs interfere with brain dopamine function. This insight was derived from two distinct lines of research. The first line originated from the discovery in 1956 that reserpine depletes brain serotonin. This finding resulted in a sequence of studies that led to the discovery that brain dopamine is involved in neuroleptic-induced extrapyramidal motor disturbances. The second line of research was aimed at determining the mechanism of action of psychomotor stimulants. This research produced evidence that stimulants directly or indirectly activate brain dopamine receptors. Because nonreserpine neuroleptics such as chlorpromazine block stimulant-induced movement, these findings suggested that neuroleptics were dopamine antagonists. Most previous accounts of the development of the dopamine hypothesis of schizophrenia emphasize the first line of research and ignore the second. 相似文献
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