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In 2003, a presidential decree enacted legislation guaranteeing Italian voters overseas the right to postal voting as well as parliamentary representation within their respective electoral constituency. The electoral weight of the overseas-based constituent had a remarkable effect on the 2006 election results. In the tightest vote in the Republic's history, the vote of overseas Italians, which was one of the decisive features of the election, helped provide the winning centre-left coalition with a slender majority in the Senate. Election results notwithstanding, the question of whether to grant the vote to Italians overseas has faced challenges of a procedural, normative and political nature. What may have been initially seen as a democratic right may well be cast aside as it poses challenges to overseas electoral relationships with the Italian national polity, Italian citizenship and multinational allegiances, diasporic identity, electoral participation and political representation in homeland political institutions. The overseas vote for Italians may be contested further in the near future, which could translate into a radical rethink of its validity and democratic global extension.  相似文献   
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Raw material provenance and procurement studies are an essential research line to infer landscape exploitation, mobility dynamics and territorial management among prehistoric hunter-gatherer groups. This paper proposes an original and intuitive method, the chert abundance ratio, aimed at quantifying lithic resource occurrence in the landscape while considering the geological natural factors of an area (chert-bearing formation extent, thickness, occurrence index, size and chert content). The resource availability can be statistically compared to any archaeological assemblage distribution to define the procurement strategies, whether generalist or selective, and the mobility patterns. The study area, the north-east of the Iberian Peninsula, focused in the Prades Mountains, represents a regional scenario with high chert disposal shared by several Late Upper Palaeolithic occupations. The discrimination of the procurement areas is used as a parameter for outlining the foraging radius and the territorial range, contributing to an understanding of several aspects of the settlement, such as site functions, occupation length or intensity and group size.  相似文献   
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Two Portuguese naus from Vasco da Gama's second voyage to India, left behind to disrupt maritime trade between India and the Red Sea, were wrecked in May 1503 off the north‐eastern coast of Al Hallaniyah Island, Oman. The ships, Esmeralda and São Pedro, had been commanded by da Gama's maternal uncles, Vicente and Brás Sodré, respectively. A detailed study and scientific analysis of an artefact assemblage recovered during archaeological excavations conducted in Al Hallaniyah in 2013 and 2014 confirms the location of an early 16th‐century Portuguese wreck‐site, initially discovered in 1998. Esmeralda is proposed as the probable source of the remaining, un‐salved wreckage.  相似文献   
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Our research demonstrates that the extent of isoleucine epimerisation (A/I) in fragments of avian eggshells provides geochronological information in archaeological contexts. In the archaeological sequence of Hay Cave, northern Queensland, Australia, there is an excellent correspondence between the A/I values of Australian brush-turkey (Alectura lathami) eggshells (n = 99) and independent geochronological control (n = 16 radiocarbon ages including 4 on eggshell calcite). The A/I values identify three phases of deposition during the Holocene at Hay Cave. In contrast to the Alectura eggshell A/I values, a poor correspondence was observed between the A/I values of cassowary (Casuarius) eggshells from Toé (n = 35) and Kria caves (n = 23) (Ayamaru Plateau, Papua) and the depths from which the specimens were recovered in these stratified sequences. Given coherent archaeofauna trends and radiocarbon chronologies (n = 8 and 2 eggshell calcite radiocarbon ages at Toé and Kria, respectively) with respect to depth, the variable A/I values are not explicable in terms of mixing. Rather, the variability is most likely due to exposure of the eggshells to the high temperatures of campfires. Despite the variability, eggshells with relatively low A/I values amongst specimens recovered from similar depths (and therefore presumably least influenced by high temperatures) exhibit a gradual increase in A/I with respect to depth, as expected in a stratified deposit. From this observation it is suggested that the identification of heated eggshells will increase confidence in geochronological information provided by A/I. These studies illustrate the complications that arise from campfire-induced acceleration of amino acid racemisation and emphasise that although this phenomenon is common, it is not universally encountered in archaeological contexts.  相似文献   
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A dissipative connector device, consisting of a steel plate folded at right angle along three lines to get a W-shaped profile, is proposed for the safe fastening of the horizontal cladding panels of new or existing precast structures under seismic action. Experimental tests are carried out to characterize the hysteretic behavior of the connector device. Different technological features, restraint conditions, and loading protocols are considered. Nonlinear hysteretic models are validated against the results of pseudo-dynamic tests on a full-scale prototype of precast building with cladding panels. Guidelines for the design of the dissipative connector device are provided.  相似文献   
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