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81.
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E. Fernández S. Thaw T.A. Brown E. Arroyo-Pardo R. Buxó M.D. Serret J.L. Araus 《Journal of archaeological science》2013
In the present work we attempt to recover endogenous ancient DNA from cereal grains preserved under different conditions: charred, partially charred and waterlogged. A total of 126 grains from naked wheat and 18 from barley from different sites on the Eastern Iberian Peninsula ranging from the beginning of agriculture in the region to the turn of the Common Era, were studied. Two different extraction protocols were used, a standard phenol–chloroform method and a silica-based DNA extraction procedure implemented for artificially charred seeds. Amplifications were directed to three markers: the large subunit of ribulose 1,5 biphosphate carboxylase (rbcL) and the microsatellite WCT12 in the chloroplast genome and the x and y subunits of the high molecular weight glutenin gene (Glu-1) in the nucleus. The first two were used to assess the preservation status of the samples, while with the third we tried to identify the wheat grains at species level. It was possible to obtain eleven positive amplifications in 8 partially charred seeds but only two amplifications of the Glu-1 gene from a single sample of the Early Bronze age were genome-specific. Different contamination sources were identified and reported. Cloning and alignment of sequenced clones showed a correspondence of the amplified fragment to modern wheat D genome haplotypes. This result suggests that the sample corresponds to hexaploid wheat (Triticum aestivum L.), thus being the first ancient DNA evidence to date for the cultivation of hexaploid wheat in the prehistoric agriculture of the Iberian Peninsula. Moreover, obtained results highlight contamination problems associated to the study of ancient archaeobotanical charred seeds suggest that the combination of a silica-based extraction method together with the amplification of specific targets is a good strategy for recovering endogenous ancient DNA from this kind of material. 相似文献
83.
Ian Brown 《The Journal of imperial and commonwealth history》2013,41(4):517-535
On 9 February 1947, a detachment of armed police was called into the Insein Central Gaol in the northern suburbs of Rangoon to quell a serious disturbance. The police fired into the rioting prison wards, killing four inmates—a further prisoner died of heart failure—and wounding three others. The inspector-general of prisons, Burma, the superintendent of the Insein Gaol, and the district superintendent of police were subsequently suspended from duty. This paper examines the background to the Insein Gaol shootings, the incident itself, the government-ordered enquiry into the shootings, the government's response to the enquiry's report, and the final fate of the three senior prison and police officials. The paper sets the Insein prison shootings, in all their aspects, in the context of the fierce struggle between the Burmese nationalists and a weakening British administration in the final months of colonial rule. 相似文献
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M. Leann Brown 《政策研究杂志》2000,28(3):576-596
Scientific uncertainty characterizes policy/making in many environmental issue areas. Policymakers must rely on scientists to bring environmental problems to their attention, design and prescribe policy solutions, and to define and evaluate policy effectiveness. An important theoretical question is: What role does organizational learning play in amelioration of scientific uncertainty and shaping environmental policy. This study examines the political processes and policy outcomes associated with European Union policymaking to revise water quality directives and deal with climate change to ascertain and describe the role played by organizational learning. The evidence suggests that organizational learning is occurring as an integral part of the political dynamics of policymaking in these two issue areas. 相似文献
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Devolution within the UK has produced new systems of governance within Scotland and Wales and restored to Northern Ireland local accountability following three decades of direct administration. The paper reviews the different status of Northern Ireland to provide both an understanding of the context in which planning has been set and the new structures that are taking shape. Particular focus is placed upon the ambitious mechanisms underlying the Agreement between the political parties in the province. The paper discusses how planning issues and responsibilities have moved from one highly centralized government department pre-devolution to effectively three new departments thereby providing a test not only of joined-up governance but of the ability of the new devolved structures to work effectively. Challenges posed by the different competencies are debated and emerging issues are discussed in terms of coherent planning at regional, subregional and local levels. 相似文献