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Human bones from Late Eneolithic graves and Bronze Age settlement pits in Moravia (Czech Republic) were studied to reconstruct their post-mortem histories based on the distribution of their microbial destruction. Backscattered electrons in a scanning electron microscope (BSE-SEM) were used for visual assessment of bioerosion. Visual data from the histological analysis were transformed into quantitative data using the Waikato Environment for Knowledge Analysis (WEKA) toolkit. The results show that the presence of bioerosion is different between the two groups of samples. The bones from settlement pits display extensive bioerosion whereas the bones from graves display no or arrested bioerosion. The absence of bioerosion in graves is most probably linked with tomb burials of Corded Ware Culture. Given the tombs are frequently not preserved archaeologically, the state of bone bioerosion may serve as an indicator of their existence.  相似文献   
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Four decades have passed since Harlan and Stemler (1976) proposed the eastern Sahelian zone as the most likely center of Sorghum bicolor domestication. Recently, new data on seed impressions on Butana Group pottery, from the fourth millennium BC in the southern Atbai region of the far eastern Sahelian Belt in Africa, show evidence for cultivation activities of sorghum displaying some domestication traits. Pennisetum glaucum may have been undergoing domestication shortly thereafter in the western Sahel, as finds of fully domesticated pearl millet are present in southeastern Mali by the second half of the third millennium BC, and present in eastern Sudan by the early second millennium BC. The dispersal of the latter to India took less than 1000 years according to present data. Here, we review the middle Holocene Sudanese archaeological data for the first time, to situate the origins and spread of these two native summer rainfall cereals in what is proposed to be their eastern Sahelian Sudan gateway to the Red Sea and the Indian Ocean trade.  相似文献   
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Not all general elections can be considered as being equal: some are placed in continuity with the previous political phase and therefore do not change the most relevant features of the party and political system; others, however, tend to represent a watershed between distinct political phases. Without a doubt, the 4 March 2018 Italian general elections belong to the latter category. This article analyses those same elections from three points of view: firstly, it reconstructs and explains electoral turnout, both following a long-term diachronic perspective, as well as comparing the various areas of the country from a territorial point of view. Secondly, similar diachronic and territorial comparisons are conducted with respect to electoral results, so as to clearly identify winners and losers of the 4 of March. Finally, it presents flows of votes in thirty-eight different territorial contexts (cities or electoral constituencies): in this way, it is possible to precisely reconstruct the reasons behind the ‘electoral earthquake’ of 4 March 2018.  相似文献   
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In 2015, Australia and the European Union successfully negotiated a Framework Agreement. This agreement is an essential step in establishing a stronger Australia–European Union partnership and achieving closer bilateral cooperation. For years, negotiating such an agreement had proved impossible. In the 1970s, successive Australian governments showed interest in enhanced collaboration with the European Community, but the political climate for closer relations was far from encouraging. This article explains why this was the case. In doing so, it also explores how the Whitlam and Fraser governments envisaged, framed and developed Australia’s ties with the European Community in the 1970s, and asks whether a more positive approach on their part could have led to a stronger relationship. Based on recently declassified government files, this article shows that although both Whitlam and Fraser fully grasped the importance of the European Community as an emerging international actor and were willing to deepen Australia’s ties with it, significant constraints existed against enhanced bilateral cooperation. With the Common Agricultural Policy still a considerable challenge to Australian economic interests and with the European Community focused mainly on the management of its internal market, broader political considerations were inevitably relegated to the margins of Australia–European Community consultations.  相似文献   
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On the third anniversary of the Battle of Long Tan on 18 August 1969, a simple but distinctive concrete cross was planted on the site of the battle to remember the eighteen Australian lives lost. The memorial cross was later toppled, lost and recovered but its physical form was never forgotten. In Australia, veterans made it a focus for their commemoration of all who served and died in the Vietnam War, replicating it across the country. This article analyses the complex motivations behind this process, revealing the Long Tan cross as a deeply personal symbol for Vietnam veterans and part of their fight for recognition in the aftermath of the war.  相似文献   
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The employment of timber pegs in timber structure joints is a widespread technology in the field of timber frame building in the United States, where the Timber Frame Engineering Council has published a special Standard to supplement the National Design Specification for Wood Construction. The authors have been studying the possibility of supplementing the Eurocode 5 design formulas, thought for timber joints with metal connectors, with specifications needed for a reliable design when employing timber pegs. The field of application envisaged is that of restoring timber structures and results obtained until now are quite encouraging. In this step of the research, more attention has been paid to deformation process: fir and chestnut samples have been tested to determine their dowel-bearing behavior with steel and ash timber peg while double-shear plane joints made of the same wood species, and fastened with steel as well as timber pegs, have been analyzed.  相似文献   
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