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This paper presents direct evidence of subsistence practices and pottery use at a Late Neolithic site at al-Basatîn, northern Jordan. Measurable concentrations of C16:0 and C18:0 were recovered from 8 of 10 archaeological pottery fragments through use of a microwave-assisted silica gel and aminopropyl solvent protocol developed for the isolation and concentration of free fatty acids in marine sediments. Subsequent isotopic analysis of the surviving C16:0 and C18:0 saturated fatty acids revealed ∂13C ratios consistent with those of adipose fats of ruminant and non-ruminant animals pastured on lands adjacent to the Jordan Valley. The high recovery of diagnostic compounds from the al-Basatîn material is discussed in context of a wider examination of the initial development and use of pottery in the Fertile Crescent, and the emerging debate concerning the efficacy of stable carbon isotope values in characterizing organic residues embedded in pottery fragments recovered from the earliest ceramic horizons in the Middle East and Europe.  相似文献   
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The coefficients of migration intensity calculated by Rybakovskiy (see preceding article) are used to derive a system of migration regions, which are defined as groups of administrative units with maximum internal interaction and a minimum flow across migration-defining boundaries. The technique is based on the assumption that gross migration flows may provide a reasonably objective basis for determining practical boundaries within a national territory. The technique yields a hierarchy of regionalizations that is then compared with the official Soviet system of major economic regions. None of the 10 major economic regions in their entirety turn out to conform to strong migration components, although one migration cluster, focused on the Northwest, corresponds fairly closely to the official Northwest region. For the rest, administrative units of the Far East and Siberia are grouped together in one migration cluster, as are the southern Volga region and the North Caucasus. Units of the Central [Industrial] region also tend to cluster with those of the Central Chernozem region. However, the most tightly connected migration dyads and triads are found to be wholly contained within the official economic regions, so that the most highly intensive migration streams are found not to cross the boundaries between the official regions. (The study was supported by a grant of the National Science Foundation for work on applications of graph—theoretic clustering and transaction flow analysis in geography and regional science.)  相似文献   
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Quantifying the geometries (defined here as width, height and depth of burial) of archeological structures within resistivity models produced as a result of the regularization constraints used in most inversion algorithms is difficult, especially when structures are closely spaced. Here we apply the watershed by simulated immersion method of boundary detection to smooth 2D resistivity images generated for synthetic and field data over 3D targets. The synthetic studies include a single cavity model, a model for two widely spaced cavities (spacing ? unit electrode spacing) and a model for two closely spaced cavities (spacing < unit electrode spacing). We also examine a single-cavity model where a relatively resistive overburden, common at archaeological sites in Egypt, is included. In the case of the single cavity models, the maximum error for any geometries are 18% for the model without the resistive overburden and 10% for the model where the overburden is included, whereas it increases to 24% for the widely spaced model and 40% for the closely spaced model. Despite, the higher errors in the closely spaced cavity model, application of the algorithm confirms the presence of two features, which is not ascertainable from the smooth resistivity images. Boundaries detected with the watershed algorithm are subsequently used to define a disconnect in the regularization, resulting in a markedly improved estimate of the resistivity structure (particularly for the closely spaced cavity model) in a second inversion step using the model obtained from the smoothness constraint inversion as the starting model. This revised resistivity model also results in a lower root-mean-square (rms) misfit between measured and theoretical data, and between synthetic and inverted models. We demonstrate how the method can be applied on images from the archaeological site at Qurnet Murai, Luxor City Egypt.  相似文献   
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The argument of this essay is that current U.S. strategic postures and weapons systems, based essentially on mutual assured destruction (MAD), are defective, in that they over-deter and under-defend. MAD provides far more than sufficient deterrence against deliberate, full-scale nuclear war launched by the government of the Soviet Union, but provides little deterrence and no defense against the far more likely nuclear catastrophe of the future: an accidental, unauthorized, or third-party missile attack. The proposed solution is the reintroduction of superpower ABM (anti-ballistic missile) protection, on a limited, negotiated basis, which could provide defensive systems heavy enough to defend against light attacks but not heavy enough to defend against full-scale superpower attacks (and thereby undermine deterrence).  相似文献   
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