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61.
We present the first analysis of the influence of climate change on carbon and oxygen isotope fractionation factors for two saccharides (glucose and α-cellulose) of pine wood. The conifers grew in the Niepo?omice Forest in Poland and the annual rings covered a time span from 1935 to 2000 AD. Glucose samples from acid hydrolysis of α-cellulose were extracted from annual tree rings. The carbon and oxygen isotope fractionation factors between glucose and α-cellulose were not stable over time. The mean value for the carbon isotope fractionation factors between glucose and α-cellulose was greater than unity. The mean value for the oxygen isotope fractionation factors between glucose and α-cellulose was lower than unity. We established, with respect to climate change, the significance of the interannual and intraannual variation in the carbon and oxygen isotope fractionation factors between both saccharides. We used moving interval correlation results for May of the previous year through September of the current year using a base length of 48 years. The relationship with summer temperature is the main climate signal in the carbon isotope fractionation factor between glucose and α-cellulose. The relationship with autumn sunshine is the main climate signal in the oxygen isotope fractionation factor between glucose and α-cellulose for the tree ring chronology. 相似文献
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Anna M. Cienciala 《国际历史评论》2013,35(1):129-145
The Activities of Polish Communists as a Source for Stalin's Policy Towards Poland in the Second World War 相似文献
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Emilie-Pauline Gallié Anna Glaser Valérie Mérindol Thierry Weil 《European Planning Studies》2013,21(10):1653-1675
This article explores the diversity of 66 French competitiveness clusters, which were all accredited in 2005 according to the same specifications, by characterizing the initial context in which they emerged and taking a close look at the link between this initial context and their current performance. Since French competitiveness cluster policy is based on state co-funding of R&D projects, we establish a typology based on a multiple component analysis and a hierarchical ascending classification of the R&D potential of the cluster's territory, the respective R&D efforts of companies and academic laboratories, the kinds of actors setting up the cluster and their pre-existing relationships. We then measure the differences among the five classes relating to their clusters' capacity to obtain state funding for their projects. Our results show that initial context can partially explain competitiveness clusters' performance. Competitiveness clusters in territories possessing significant R&D resources, and involving large companies capable of organizing projects, are the most efficient in obtaining state funding. In contrast, competitiveness clusters without prior cooperation experience perform poorly. 相似文献
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Drawing on theories of space, gender, and participatory learning, central concepts in feminist pedagogy, the author designed a university-level general-education course that took the Twenty-Five Ladies Tomb in southern Taiwan as the focus of a field study and class discussion. This local gendered site, which commemorates a 1973 ferry accident that killed 25 unmarried young women working in Kaohsiung, raises issues about patriarchy in Taiwan, gender inequities in traditional Han customs, and women's labor. The course relied on guided class discussions and focus-group discussions, culminating in a visit to the site. Face to face with the researched, the author not only built an inclusive and supportive relationship with students in the classroom, but also put her researcher's reflexivity into teaching practice. Research results indicate that the freedom of the class discussion format succeeded in breaking down the logic of binary opposition that accompanies the traditional gender duality of male/female. Avoiding a top-down teaching style also minimized students' resistance to perspectives emphasizing gender equality. 相似文献
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Wendy van Duivenvoorde Jim Stedman Kjell Billström Zofia Anna Stos‐Gale Michael McCarthy 《International Journal of Nautical Archaeology》2013,42(1):150-166
The Dutch United East India Company ship Zuiddorp vanished on its way to Batavia in 1712 – its last port of call was the Cape of Good Hope. After its wreck was found on the Western Australian coast, archaeological investigations resulted in the retrieval of 21 lead ingots. Recent study of this artefact assemblage, comprising both great pigs and pieces, suggests that they were of north English origin. Historical records indicate that the Dutch procured large quantities of lead from English sources and maritime trade links between English and Dutch ports were well established at the beginning of the 18th century. © 2012 The Authors 相似文献
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Johannes de Beer Anna Seither Michel Vorenhout 《Conservation and Management of Archaeological Sites》2013,15(1-3):99-115
The World Heritage Site of Bryggen in Bergen, Norway, has experienced significant degradation of archaeological deposits as a consequence of changes in the soil water and groundwater balance after urban redevelopment adjacent to the heritage site. Additionally, groundwater temperatures below the heritage site were found to be significantly higher closer to the redeveloped area. One of the main mitigation measures taken to reduce the degradation of the archaeology has been the construction of a hydrological barrier along the sheet piling that divides the redeveloped area and the historic site. A shallow subsurface infiltration system was designed to achieve groundwater levels and flow conditions that are optimal for the preservation of archaeological remains directly along the sheet pile, while reducing drainage and subsidence also further upstream. Monitoring of groundwater level and temperatures after implementation of the hydrological barrier shows that groundwater levels and flow conditions have improved with respect to optimal preservation conditions, and groundwater temperatures have generally been reduced by up to 2 °C. 相似文献