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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   
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Physiocracy is still sometimes seen as an oddly archaic programme of agricultural development. The aim of this paper is to show that one of the Physiocrats’ prime concerns was to take the subject of agriculture out of international relations. The fiscal regime that was central to Physiocracy was designed to make every large territorial state self-sufficient and, by doing so, to break the connection between modern great power politics, the international division of labour, and the politics of necessity. From this perspective, the memorandum that Victor Riqueti, marquis de Mirabeau, sent to the Berne Economic Society in 1759, contains an early indication of what, had the Physiocratic programme ever been implemented in full, a world reformed on Physiocratic lines might have looked like.  相似文献   
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In luminescence dating, the potassium concentration significantly contributes to the dose rate value in the age estimation. Within this study, fine-grain thermoluminescence dating has been applied on sherds of calcareous pottery of known age, excavated at a Roman site in Mallorca, Spain. For those of the samples that showed signs of severe potassium leaching, according to chemical and mineralogical examination, the thermoluminescence analysis provided overestimated dates. By using the known archaeological age of the samples, a corrected dose rate value can be estimated which provides the potassium concentration averaged for the burial period. Finally, a step-like model can then be used to estimate the fraction of the burial period after which most of the alteration effects took place.  相似文献   
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In this study we consider the development of clinical neurology in the eighteenth and the nineteenth centuries focusing on European influence on Russian medicine. Russian physicians readily accepted newly described clinical signs, theories, and classification of nervous diseases designed in Europe. This influence initiated neurology's separation from general medicine and its transformation into a new clinical discipline. In Russia this happened already in the 1860s, decades before the similar trend in Europe. The Russian example is nearly unknown in the general history of neurology. It illustrates the relationships between physiology and practical neurology at the moment of establishment of the new discipline. It also shows that the Russian physicians of the time readily accepted European medical knowledge putting it immediately into medical practice and education.  相似文献   
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Michael Hutnak 《Geofluids》2007,7(4):468-469
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