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We investigated the contribution of freshwater resources to the diet of seven Late Mesolithic hunter-gatherers (ca. 5300–7000 BC) from Northern France and Luxembourg using stable isotope ratios. In addition to the carbon and nitrogen stable isotope ratios (δ13C, δ15N), we explored the potential of the sulphur isotopic ratios (δ34S) to detect and quantify the proportion of protein derived from aquatic foodstuff. In only two sites, animal remains from an associated settlement were available and subsequently examined to decipher the isotopic differential between terrestrial and freshwater resources. The quantification of their relative contribution was simulated using a Bayesian mixing model. The measurements revealed a significant overlap in δ13C values between freshwater and terrestrial resources and a large range of δ15N values for each food category. The δ34S values of the aquatic and terrestrial animals were clearly distinct at the settlement in the Seine valley, while the results on fish from Belgium demonstrated a possible overlap in δ34S values between freshwater and terrestrial resources. Local freshwater ecosystem likely contributed to ca. 30–40 % of the protein in the diet of the individuals found in the Seine settlement. Out of this context, the isotopic signature and thus contribution of the available aquatic foods was difficult to assess. Another potential source of dietary protein is wild boar. Depending on the local context, collagen δ34S values may contribute to better assessment of the relative contribution of freshwater and terrestrial resources.  相似文献   
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In 1665, Robert Hooke published his major work in microscopy, Micrographia, a defense of experimental philosophy. The following year, Margaret Cavendish, Duchess of Newcastle, published at her own expense a treatise and a novel that undermined the basis of this new science. The dispute broke out at the initiative of the Duchess, in the context of a vast controversy about the legitimacy and the efficiency of optical instruments in natural philosophy. All the figures of the dual are used, except one: the counterattack. Cavendish, indeed, was alone on the battlefield. Is it possible to call a dual a battle with only one combatant? This particular case of dispute that stops owing to the shortage of combatants is the subject of this article.  相似文献   
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In Guatemala local perspectives on heritage often remain unheard. In this paper a case study is presented to show the complex relationship between the highland site of Iximche’ and Tecpán, an Indigenous community nearby. Although Iximche’ is of little importance to the local economy, its significance is derived from its role as a field for different kinds of social and religious interactions. Traces of a spiritual relationship to this place can be dated back to the colonial period and today Maya from all over Guatemala go there to perform ceremonies. The place has also become a focal point of identity constructions for locals, Pan Mayan activists and the nation itself. The ruins of Iximche’ play an important role in the construction of collective memory which also includes ideas coming from external players such as Christian churches, the national government, Mayan activists, and archaeologists as well.  相似文献   
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ABSTRACT

Nuclear cooperation has been a consistent feature of the Australia-US alliance. In the 1950s and 1960s, Canberra explored transferring US nuclear weapons to Australian forces operating in Southeast Asia. Since the 1960s, Australian governments have supported hosting joint facilities that contribute to America’s ability to execute global nuclear operations. And Australia has regularly invoked the nuclear umbrella as part of the alliance. We explain the key sources of nuclear cooperation in the alliance by leveraging realist and institutionalist theories of alliance cooperation. While realism explains limits to US nuclear commitments in the 1950s, institutional explanations are more relevant in pinpointing the sources of nuclear cooperation and in explaining why Australia has often achieved its policy preferences as the junior partner.  相似文献   
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