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921.
A successful outcome of the 2010 Nuclear Non-Proliferation Treaty (NPT) Review Conference is widely seen as vital if the NPT is to continue to play an important role in preventing nuclear proliferation. Focusing on the concept of trust, this article offers a novel perspective on the treaty and its future prospects. Too often dismissed as impossible or dangerous in international politics, trust has received little attention from both academics and practitioners. This article challenges this predominant view by making a case that the NPT establishes and embodies a series of trusting relationships between states. Trusting relationships are analysed as a way in which states relate to each other, taking into account both interests as well as promises. It does not make the case that once such relationships are established they will remain constant, but rather that trusting relationships are dynamic. They can be strengthened or weakened depending on the choices of actors. The article shows how trusting relationships have underpinned the NPT from its beginning and charts their evolution by reference to three key sets of relationships. These are, first, the relationships between the recognized nuclear weapon powers and the non-nuclear weapon states; second, those among the recognized nuclear weapon states; and third, those between the NPT signatories and those states remaining outside of the treaty. For each set of relationships the problems and issues that have eroded trust are outlined and the steps that might lead to the overcoming of these strains and the strengthening of the trusting relationships are discussed. By understanding the NPT through the prism of trust, the article sheds new light on both the achievements of the treaty as well as its potential fragility. At the same time, such an analysis opens up the directions of policy crucial to strengthening the treaty at the Review Conference and beyond.  相似文献   
922.
923.
924.
Recent innovations in portable energy-dispersive X-ray fluorescence (PXRF) spectrometry have increased its utility for the geochemical characterization of obsidian artifacts for archaeological provenance research. However, concerns over the utility of PXRF instrumental analyses have been raised, focused on the validity and reliability of the geochemical data produced. Here we adopt the framework of Richard Hughes (On Reliability, Validity, and Scale in Obsidian Sourcing Research, 1998), whereby reliability addresses instrument stability and issues of measurement while validity pertains to an instrument’s ability to discern geochemical source provenance. This is done in order to test the utility of PXRF instruments for archaeological provenance research. k-Means cluster analysis was used to test the accuracy of PXRF through statistical comparison of data acquired via laboratory and portable energy-dispersive XRF instruments. Multivariate analysis was employed to demonstrate obsidian source representation at two Classic Maya archaeological sites in southern Belize – Uxbenká and Ek Xux – and to test the validity of data obtained from a PXRF instrument in answering archaeological research questions pertaining to regional interactions between lowland Maya polities. Results suggest that portable XRF instruments produce internally consistent results. However, data acquired from a PXRF instrument are not statistically equivalent to other XRF instruments. This is to say that while PXRF is not a reliable technique, it is valid for questions pertaining to geochemical source representation.  相似文献   
925.
The use of immunological techniques for identifying the origin of proteins and inferring foodstuffs exploited by prehistoric occupations has been conducted for several decades. Cases of experimental laboratory and archaeological studies have shown the potential of these techniques for reliable results. However, very few of these case studies employ archaeological sites that have excellent preservation and high-resolution spatial contexts between identifiable faunal remains, features, and stone tools. We present an assessment of the identification reliability of one immunological technique, protein radioimmunoassay (pRIA), using faunal remains and stone tools from two sites from arctic and subarctic contexts. The results of this research indicate that, even in contexts with excellent preservation, the identifications produced by the pRIA technique are subject to misidentification and cross-reactions due to diagenetic alteration of proteins. We propose a higher minimum reaction value (percent binding of labeled antibody) that mitigates these effects, and renders the pRIA results more reliable for ancient, poorly preserved organic remains.  相似文献   
926.
Richards et al. (2000) reconstructed the diet of the human remains found in Gough's and Sun Hole Cave through isotope analysis. They concluded that these people consumed an entirely terrestrial-based diet. Their reconstruction was based upon comparison of the results from human bones with those from a very small number of associated animals. The diets of the Gough's and Sun Hole Cave human were different from the other six Upper Palaeolithic humans from the British Isles for which dietary information has been obtained through isotope analysis. The work of Richards et al. (2000) suggests that they were the only ones for whom marine or freshwater resources did not play a significant role in their diets. We test this through further analyses of faunal remains from Gough's Cave, Sun Hole and other contemporary sites (Kent's Cavern, Aveline's Hole, Kendrick's Cave). Despite the limited faunal sample, the original palaeodietary reconstruction is broadly consistent with our findings. The isotope values of the main protein sources consumed by the humans from both sites are consistent with those of red deer and bovines, and, for a single individual, with that of horse and red deer. Reindeer was postulated in the original reconstruction as a potential food source, but this seems very unlikely based on our isotope reconstruction and the archaeological remains.  相似文献   
927.
Is it possible to identify cooked, rather than burnt, bone? Mild heating (≤100 °C,1 h) – typical of cooking – does not lead to detectable changes in any biochemical parameter of bone yet measured. If it is only possible to detect charred bone, how is it possible to detect cooking in the archaeological record? In a previous paper (Koon et al., 2003, J. Arch. Sci.), we used a Transmission Electron Microscopy (TEM) based approach to investigate changes in the organization of the bone protein, collagen, as it is heated, using bone from heating experiments and short term burials. The work revealed that mineralized collagen, despite requiring aggressive treatment to gelatinise the protein (e.g. 90 °C, 240+ h), readily accumulates minor damage. We believe that the presence of mineral matrix stabilises the collagen enabling the damage to accumulate, but preventing it from causing immediate gelatinisation. Once the mineral is removed, the damage can be observed using appropriate visualization methods.  相似文献   
928.
The discovery of a Late Bronze Age trading vessel at Uluburun near Ka? off the Turkish coast offers exciting possibilities for our understanding of Bronze Age trade. On board the ship was a large consignment of glass ingots that were assumed to originate either from Mesopotamia or Egypt. This paper presents the results of major and trace elemental analyses of three deep blue and turquoise glass ingots from the Uluburun wreck, and for the first time securely demonstrates that their composition is consistent with an Egyptian origin. The compositional similarity of the glass ingots to glasses from the Mycenaean world suggests that Egypt was exporting to that region via trading ships such as that from Uluburun.  相似文献   
929.
Research on past human diets in the southern Lake Titicaca Basin has directed us to investigate the carbon and nitrogen stable isotopes of an important dietary element, fish. By completing a range of analyses on modern and archaeological fish remains, we contribute to two related issues regarding the application of stable isotope analysis of archaeological fish remains and in turn their place within human diet. The first issue is the potential carbon and nitrogen isotope values of prehistoric fish (and how these would impact human dietary isotopic data), and the second is the observed changes in the fish isotopes through time. Out of this work we provide quantitative isotope relationships between fish tissues with and without lipid extraction, and a qualitative analysis of the isotopic relationships between fish tissues, allowing archaeologists to understand these relationships and how these values can be applied in future research. We test a mathematical lipid normalization equation to examine whether future researchers will need to perform lipid extraction procedures for Lake Titicaca fish. We also analyze a number of aquatic plants to better understand the range of isotopic signatures of the Lake Titicaca ecosystem. We use these data to better understand prehistoric human diet and the role that fish may have played in the past as well as potential changes in local lake ecology through time.  相似文献   
930.
In this paper, the characterization of Roman amphorae from the Porto dos Cacos (PC) and Quinta do Rouxinol (QR) workshops, in the Tagus estuary, dating to a period between the 1st and 5th century AD was carried out on the basis of instrumental neutron activation analysis data on 260 amphorae fragments, together with mineralogical compositional studies obtained by X-ray diffraction.  相似文献   
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