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991.
992.
Brian Finucane Patricia Maita Agurto William H. Isbell 《Journal of archaeological science》2006,33(12):1766-1776
This paper reports δ13C and δ15N values for human and animal skeletal remains from the Middle Horizon (AD 550–1000) site of Conchopata in the Peruvian highlands. The data indicate that maize was the dietary staple for both humans and the majority of animals at this urban site. Camelids at the site segregated into two groups according to δ13C values, reflecting two distinct animal management strategies. Human infants were found to have elevated δ15N values, reflecting the trophic level effect of breastfeeding. No sex based differences in diet were observed. 相似文献
993.
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996.
M.F. Deguilloux L. Bertel A. Celant M.H. Pemonge L. Sadori D. Magri R.J. Petit 《Journal of archaeological science》2006
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
997.
Although China is one of the world's largest producers and consumers of genetically modified (GM) crops and derived food products, little is known about the level of Chinese consumer awareness, understanding and acceptance of GM food. Initially, China pursued relatively aggressive policies for biotechnology development, but in recent years, the central government has become more sensitive to the potential environmental risks of transgenic food crops. To protect domestic biotech industries, the state plays a critical role in the politics of biotechnology, and does not allow GM food to become a prominent public issue. This contribution reports on a survey of 1,000 urban respondents. It demonstrates that most consumers lack the most basic understanding of biotechnology and its potential risks. The majority of the respondents (60 per cent) were either unwilling to consume GM food or were neutral about the idea, but when given neutrally‐worded information about potential GM food allergenicity, the willingness to buy dropped sharply. This might point to future scenarios of consumer resistance against GM food as has happened in European Union member states. This effect demonstrates the malleability of the Chinese consumer in a context of limited understanding and inadequate access to information. 相似文献
998.
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
999.
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
1000.
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