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151.
The “Christmas Cave”, a cave in the Qidron Valley near the Dead Sea and Qumran, has yielded a complex collection of plant-derived rope and fabric artifacts. Using polymerase chain reaction (PCR) to amplify DNA of the samples, we estimated the sizes and determined restriction patterns and base sequences of chloroplast genes, primarily rbcL (gene for the large subunit of ribulose bisphosphate carboxylase). DNA was successfully extracted from all samples, but was limited to sizes of approximately 200–300 base pairs. As expected, the DNA extracted from the samples was identified as coming primarily from flax (Linum usitatissamum L.), but two samples had a significant fraction, and all samples had at least a trace, of hemp (Cannabis sativa L.) DNA. Artifacts from the Christmas Cave were thought to date from Roman times, but it was thought possible that some could be much older. Accelerator mass spectrometry (AMS)-based 14C dating confirmed that the samples contained representatives from both the Roman and Chalcolithic periods. This paper provides a synthesis of DNA, isotope, and literary analysis to illuminate textile history at the Christmas Cave site.  相似文献   
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Abstract

The Climate Challenge Fund (CCF) is the Scottish Government's flagship initiative addressing the twenty-first century's core concern: environmental challenges. The CCF seeks to reduce carbon emissions explicitly through community. Building on community's long and strong social science heritage, this paper outlines the CCF's tacit and unspoken community assumptions. Through these assumptions, this policy (re)produces, prefigures and performs a particular form of community, this being community's elision with locality, and synonym for place, rurality or neighbourhood. Taking on these tacit assumptions is demonstrative of their belief in the effectiveness of such community. After exploring the CCF, its source and structure, the paper delves into empirical work situated at all levels of the CCF's funding chain. It then teases out how the assumptions around – and the need to demonstrate – community help determine the projects selected, and subsequently the vision of community chosen, enacted and mobilised. The CCF (re)produces a particular vision of community with implications for who receives funding, how environmental action is framed and also for the future of community in Scotland.  相似文献   
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Distance Transformation and Distance Decay Functions   总被引:1,自引:0,他引:1  
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