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991.
992.
A total of 51 ancient oak wood samples originating from various European archaeological sites, dating from the Neolithic period to the 18th century, were assayed for the presence of reproducible chloroplast (cp) DNA sequences. Five polymorphic chloroplast fragments were targeted. Only five of the samples could be fully genetically characterised, revealing four different oak cpDNA haplotypes. In all cases, the haplotypes detected on ancient woods and the haplotypes characterised from fresh samples from the same localities matched. Overall, this congruence is consistent with a genetic continuity between ancient and modern European oaks, confirming the hypothesis that the mapped genetic patterns largely reflect the original structure that established during the post-glacial. This stability of the genetic structure implies that, in the future, the technique could be used to infer or confirm the transport of wood by man, providing interesting perspectives for the genetic analysis of ancient woods.  相似文献   
993.
This paper presents the results of a metallographic examination of Eneolithic and Early Bronze Age axes from the Northalpine region of central Europe. During this period, different types of copper were in use: arsenical copper, Fahlerz copper and tin bronze. We examine if and to what extent the different properties of the metals used were known to prehistoric metalworkers and actively manipulated in the production of the axes. The development of methods of casting and smithing is discussed. Both aspects contribute to our understanding of the nature of prehistoric technological change. During the Early Bronze Age of the Northalpine region, different traditions of early metallurgy can be identified, which differ in their use of Fahlerz copper, their attitude towards tin alloying and the use made of tin bronze in the production of the axes. These traditions can only be adequately described by reference to both composition—that is, access to different types of copper as well as tin—and knowledge of the production techniques provided by metallographic data.  相似文献   
994.
In a recently published study of Romano‐British colourless glass compositions, using inductively coupled plasma spectroscopy, 28 glasses from Colchester sampled in a previous study were resampled. This was done deliberately, with a view to examining the repeatability of results from sampling on different occasions. We report on our results here, developing in the process some simple statistical methodology that could be applied in similar situations. The potential for combining analyses undertaken at different times is discussed and illustrated.  相似文献   
995.
Methods for evaluating regional and urban policies have become increasingly sophisticated in recent years. However, this paper argues that the evaluation of Structural Funds programmes has systematically underplayed the effect of governance on both programme design and implementation. This paper uses the role of voluntary and community sector organizations in promoting community economic development initiatives within the European Union's Structural Funds programmes in South Yorkshire as a case study. An argument is made for extending evaluation methods, especially theory-based evaluation, through using multi-level governance as a “theory of change”. A key finding is that to explain how programmes work, evaluators need to consider formal partnership and management arrangements, their traditional focus, but also wider governance structures and the importance of informal policy networks. Such a focus allows for a consideration of issues such as resource mobilization and power.  相似文献   
996.
This paper presents the results of analyses of metal artefacts discovered at a multiphase site in Nowe Brzesko, Małopolskie Voivodeship, Poland. Fieldwalking prospection led to the discovery of steely iron objects, ploughed out on the site among other numerous archeological finds. A prospecting sondage yielded more corroded metal artefacts, identified mainly as agricultural tools (e.g. sickles, scythes). These chronologically nondistinctive artefacts could be assigned to the third to fourth century AD using radiocarbon dating, complemented by metallurgical analysis. The results open up new research perspectives on the economy and society of the Przeworsk culture in the Late Roman period.  相似文献   
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Climate change threatens many well-preserved archaeological sites in the Arctic. The paper presents the first Arctic multi-threat assessment focusing on the Nuuk region of Greenland. The results suggest that the majority of the 336 known archaeological sites are already exposed to impacts from microbial degradation, permafrost thaw and vegetation, and that these impacts will increase over the next 80 years. Additional impacts from coastal erosion are only noted at a limited number of sites due to a predominant consolidated and uplifting coast. The applied methods represent an important first step to identify threatened sites and emphasize important data limitations.  相似文献   
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