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Annick Vuissoz Michael Worobey Nancy Odegaard Michael Bunce Carlos A. Machado Niels Lynnerup Elizabeth E. Peacock M. Thomas P. Gilbert 《Journal of archaeological science》2007
We have investigated the survival of PCR-amplifiable mitochondrial and nuclear DNA in a small number of modern and medieval bovine leather samples. The results of this preliminary investigation demonstrate that, while no nuclear DNA can be PCR-amplified from any of the specimens, mitochondrial DNA can be amplified from all samples. To investigate this contrasting pattern of DNA survival further, we have vegetable-tanned cow skin in our own laboratory, and directly assayed the survival of PCR-amplifiable mitochondrial and nuclear DNA at each step of the process. The results indicate that nuclear DNA is reduced to sub-amplifiable levels as a result of the tanning baths, whereas amplifiable mitochondrial DNA survives the complete process. Our results suggest that old and archaeological bovine leather may represent a useful source of genetic information, although this information will most likely be limited to that which can be gained from mitochondrial DNA. 相似文献
74.
The Swiss Cantons had no greater admirer in the eighteenth-century than the French political thinker Gabriel Bonnot de Mably. The feeling was mutual, at least to some extent, since the Bernese Patriotic Society awarded its first prize in 1763 to Mably, for his dialogue Entretiens de Phocion. The prize then led to an exchange of letters, stretching across some two decades, with Daniel Fellenberg, founder of the Patriotic society—the most important block of Mably's correspondence to have survived. This essay considers the 1763 prize and the correspondence with Fellenberg for the light they cast both on Mably and on Bernese participation in the wider currents of eighteenth-century thought. 相似文献
75.
Prof. Dr. Thomas Foken 《Standort - Zeitschrift für angewandte Geographie》2007,31(3):150-152
Zusammenfassung Das Klima von Oberfranken liegt in einem übergangsbereich zwischen ozeanisch und kontinental gepr?gten Klimaten. Der Beitrag
stellt langj?hrig ermittelte Klimadaten und Klimatrends für die Stadt Bayreuth vor. Er geht auf die Herausforderungen ein,
die sich daraus für die Stadtplanung ergeben, auch und besonders im Zusammenhang mit dem Klimawandel. 相似文献
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The interpretation that a rock has been subjected to cultural utilization is a basic element of hunter-gatherer research. The fracture mechanics of the flaked stone tool production process are well understood and the material residues are routinely identified during fieldwork. Conversely, non-percussion processes such as hot-rock technology, which can result in rock fracture, are less well understood. An experimental study has been developed to examine the fractured gravels observed at a prehistoric site on the Southern Plains (USA). The experiment has sought to determine whether cultural or natural agencies were responsible for the production of the angularly fractured rocks. The positive results of the experiment indicate that not only were humans most likely responsible for the breakages, but also that the fractured rocks often exhibit distinctive morphologies that may be identified during fieldwork. This simple experimental methodology is applicable to other hunter-gatherer sites where the depositional environment is not conducive to the structural preservation of features such as hearths. 相似文献
79.
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
80.
Thomas Duddy 《European Legacy》2007,12(3):357-359