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101.
The division of land on Dartmoor during the Bronze Age by the construction of moor-wide boundaries known as reaves represents a significant development in agricultural practice and land tenure. Previous research relating to the Dartmoor reaves suggests this way of life may have continued for no longer than 200–400 years. It has been suggested that their abandonment occurred as the result of a deteriorating climate, although there are no published palaeoclimatic reconstructions from the area. We therefore test the hypothesis that on Dartmoor, a marked climatic deterioration occurred in the late Bronze Age that can be linked to the abandonment of the reaves. A palaeoclimatic reconstruction derived from testate amoebae and peat humification analyses is presented from Tor Royal Bog, central Dartmoor, the first such record from southwest England. A major shift to a cooler and/or wetter climate is inferred from ca. 1395 to 1155 cal BC that is coincident with the period hypothesised as encompassing the abandonment. This climatic deterioration is replicated in sites in northern Britain, suggesting it was a widespread event. It is concluded that while the evidence supports a climatically forced retreat, there are a range of other socio-economic factors that must also be taken into consideration.  相似文献   
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In 1993 the "don't ask, don't tell" policy legislated the silenceof gay and lesbian soldiers on active duty and in the reserves.This silence about gays in the military has led to a collectiveamnesia about the patriotic service and courageous sacrificesof homosexual troops. If we forget that gay and lesbian Americanshave served their country, then we as a nation are much lesslikely to view them as full citizens, deserving of civil rightsand equal protection of the law. Oral history provides one wayto break this silence, to "ask and tell" about the militarycareers of gay and lesbian soldiers and to allow these veteransto speak for themselves about the current military policy. Basedon more than fifty interviews with gay and lesbian veterans,this article chronicles the evolution of military policy regardinghomosexuality since World War II, and it explores the intersectionof veterans' identities based on race, sexuality, and militaryservice. As these interviews illustrate, gays and lesbians haveserved honorably in the military during times of war and peace.Far from undermining unit cohesion or morale, these troops havestrengthened America's armed forces. Interviews with gay andlesbian veterans provide an opportunity to explore several themesunderlying the debate about homosexuality and military service:1) the relationship between racism and homophobia in the military;2) varying attitudes about military service within gay communities;3) contrasting experiences of gay men and lesbians in the military;and 4) the evolving nature of gay veterans' identities.  相似文献   
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The olive tree (Olea europaea) was domesticated by vegetative propagation of selected wild individuals with superior fruit. Later, new cultivars were established repeatedly from feral trees or from crosses between wild, feral, and domesticated trees. Thus the genetic background of many contemporary domesticated lines is a mixture of ancient cultivars and local wild trees. Ancient DNA may illuminate the complicated process of olive domestication because such DNA sequences provide data about ancient genomes that existed closer to the domestication events. Well preserved DNA must be available for such studies, even though in the Mediterranean region, where olive cultivation took place, the climatic conditions are not favorable for DNA preservation. To select for well preserved pits we measured their proportions of lignin by IR spectroscopy, and correlated this with parameters of DNA quality such as template length in an olive-specific repeat array, and template quantity as determined by real-time PCR amplification. Archaeological pits that passed these tests did contain high quality ancient DNA. We present the first ancient olive DNA sequences and compare them to modern wild, feral and domesticated lines.  相似文献   
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ABSTRACT

Whilst Western societies may have reached ‘peak car’, young people are arguably the most significant group whose levels of car ownership, use and driving licence acquisition have declined. Against this backdrop, the paper discusses qualitative research conducted in Reading, UK, considering young people’s (aged 12–20) views about bus travel. Whilst current pricing structures (both in Reading and across the UK) often offer under 18s discounted travel, the paper explores young people’s intentions about future travel as young adults. Drawing upon theorisations around youth transitions, we discuss how young people expect their mobility patterns to change as young adults in complex, shifting, fluid ways, and to involve multi-modal travel. Young people construct complex choice biographies through which they plan pathways to navigate these mobility transitions. Although a small-scale study, this paper also offers some insights into the challenges, complexities and limitations of researching mobility intention.  相似文献   
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Destruction events in multi-period sites are valuable marker horizons that represent time-synchronous events across the site and sometimes between sites. Destruction layers often preserve rich finds that provide insights into site use. Here we use both macro- and microarchaeological methods to study a destruction event from the late 9th century at Tell es-Safi/Gath in Israel. A major conflagration at this specific location resulted in the consolidation of parts of the roof construction materials, thus enabling us to differentiate between roof, walls and floor materials. We could reconstruct the events which lead to the formation of an approximately 80 cm thick layer. The base of this layer that overlies the floor surface is a thin charred organic material-rich ash layer. As the clays in this layer were not altered by heat and the ceramics still have preserved residues, we conclude that the ash was produced elsewhere and was redistributed to this location. Ceramics that are associated with burnt roof sediments do not have preserved residues. We also estimate the time that each of the accumulation events might have taken, and conclude that this accumulation occurred over decades. The architecture and artifacts found within and beneath the destruction do not allow us to unequivocally identify the function of this area prior to destruction. We do however identify an unusual bin and associated stone pavement, and a corner rich in artifacts, phytoliths and charred organic material. We also show that a wall was built of fired mud bricks; a most unusual occurrence for this time period in the Levant. This study demonstrates well the usefulness of an integrated macro- and microarchaeological approach to understanding the archaeological record, as well as the benefits of using an on-site laboratory.  相似文献   
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