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91.
Lars G. Liedgren Ingela M. Bergman Greger Hörnberg Olle Zackrisson Erik Hellberg Lars Östlund Thomas H. DeLuca 《Journal of archaeological science》2007
The chronology of prehistoric Sami settlement sites has previously been established by conventional radiocarbon dating of bulk charcoal samples associated with hearths from sunken hut floors (stállo-foundations). Here we present results of a comprehensive dating exercise of stállo-foundations in the alpine area of northern Scandinavia using Accelerator Mass Spectrometry (AMS) radiocarbon dating of charcoal. Over a 3 km2 study area, AMS calibrated ages of hearth charcoal from 22 stállo-foundations across 12 sites securely date these features to between cal. AD 640 and AD 1180. Only small variations in age were found between charcoal samples from different areas of a given hearth. Statistical analysis of all the charcoal AMS radiocarbon dates obtained reveals that 12 stállo-foundations across nine sites are contemporaneous and date to the Viking Period (AD 800–AD 1050). The tightly constrained AMS-based chronology of stállo-foundations contrasts with the existing chronology based on conventional radiocarbon analysis, which places these features within a significantly greater time-frame of between AD 600 and AD 1900, with most dates ranging between AD 800 and AD 1350.This discrepancy is likely to result from the necessity of collecting composite hearth charcoal particles, which may originate from different phases of occupation, in order to achieve the required final carbon content for conventional radiocarbon analysis. We argue that the new AMS-based radiocarbon chronology of stállo-foundations presented here supersedes the existing chronology based on conventional (Gas Proportional counting) radiocarbon analysis and we advocate the use of AMS radiocarbon dating in future hearth investigations. 相似文献
92.
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
93.
Thomas Duddy 《European Legacy》2007,12(3):357-359
94.
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
95.
96.
Thomas R 《Journal of regional science》1999,39(2):359-385
The persistence of HIV/AIDS has seen a revival of academic interest in the development of modeling systems to assist understanding the population dynamics of this infection. Moreover, it has become increasingly recognized that a key component of these systems for interpreting disease prevention is their reproduction rate, which provides an indication of whether an epidemic might start in a community described by a particular set of epidemiological characteristics. The properties of these rates have been explored in detail for models of a single risk behavior but not for multiregion formats that allow for the transfer of infection between geographical units. Therefore, in this paper I derive reproduction rates for a multiregion HIV/AIDS model together with their associated critical thresholds that estimate the minimum population of susceptibles necessary for an epidemic to begin. These statistics are interpreted for a simplified global setting representing regional variations in the potential onset of HIV/AIDS. In the discussion I examine the potential applicability of these results to understanding HIV/AIDS prevention. 相似文献
97.
98.
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
99.
Street Martin Baales Michael Cziesla Erwin Hartz Sönke Heinen Martin Jöris Olaf Koch Ingrid Pasda Clemens Terberger Thomas Vollbrecht Jürgen 《Journal of World Prehistory》2001,15(4):365-453
During the past decade research into the German Final Paleolithic and Mesolithic has experienced an important revival. One clear sign of this renewed interest in the periods are the annual meetings of the Arbeitsgruppe Mesolithikum (Mesolithic Working Group) which have taken place every spring since 1992. At these meetings, which take place at changing venues, topical themes of Final Paleolithic and Mesolithic interest are presented by informal lectures and it is also possible to study regional collections (artifacts, raw materials) at first hand. Numerous contributions were subsequently published together in one volume (Conard and Kind (1998) Aktuelle Forschungen zum Mesolithikum/Current Mesolithic Research, Mo Vince, Tübingen). The present paper intends to complement that collection of papers with a synthesis of developments and perspectives and to present recent research highlights in the German Final Paleolithic and Mesolithic, together with a comprehensive bibliography, to a wider international audience. 相似文献
100.
E. Tourigny R. Thomas E. Guiry R. Earp A. Allen J. L. Rothenburger D. Lawler M. Nussbaumer 《International Journal of Osteoarchaeology》2016,26(5):818-829
A 19th‐century dog burial uncovered from a historical homelot in Toronto, Canada, provided a unique opportunity to reconstruct the individual's osteobiography. Of particular interest are the dog's very large size and a suite of skeletal pathologies. Recovery of a nearly complete skeleton combined with the use of X‐rays and micro‐computed tomography (micro‐CT) allowed for a discriminating differential diagnoses. Stable isotope analyses were applied to investigate questions of diet. Results reveal an individual who suffered greatly from disease towards the end of his life and hint at its owners attitudes towards dogs. The interdisciplinary approach applied to this case study highlights the potential information obtainable from pet burials. We argue that better analyses and reporting of pet burials will help address research questions targeting broader themes related to human–animal relationships. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献