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991.
992.
In this study we applied a multidisciplinary approach, coupling geophysical and geochemical measurements, to unveil the provenance of 170 obsidian flakes, collected on the volcanic island of Ustica (Sicily). On this island there are some prehistoric settlements dated from the Neolithic to the Middle Bronze Age. Despite not having geological outcrops of obsidian rocks, the countryside of Ustica is rich in fragments of this volcanic glass, imported from other source areas. The study of obsidian findings was carried out first through visual observations and density measurements. At least two different obsidian families have been distinguished, probably imported from Lipari and Pantelleria islands. Analysing the magnetic properties of the samples, these two main sources were confirmed, but the possibility of other provenances was inferred. Finally, we characterized the geochemical signature of the Ustica obsidians by performing microchemical analyses through electron microprobe (EMPA) and laser ablation (LA–ICP–MS). The results were compared with literature data, confirming the presence of the Lipari and Pantelleria sources (Sicily) and indicating for the first time in this part of Italy a third provenance from Palmarola island (Latium). Our results shed new light on the commercial exchanges in the peri‐Tyrrhenian area during the prehistoric age.  相似文献   
993.
Chang'an (now Xi'an) was the capital of the Western Han Dynasty and the starting point of the Silk Road. In the light of the importance of Chang'an as the centre of politics, economy and cultural interaction, the overarching question proposed in this paper is focused on its role in the mirror production and distribution network during Han period. On the basis of chemical and lead isotopic analyses of 34 Han mirrors, this paper discusses the potential existence of a mirror production centre in Chang'an. Meanwhile, a comparative study with mirrors uncovered from the south‐western frontier and from Central Asian and North‐East Asian countries offers new insight into these related issues.  相似文献   
994.
We have determined the composition of rock art pigments from two megalithic barrows located in the north of Portugal. The use of XRD, SEM–EDS and FT–IR spectroscopy confirmed the presence of hematite and kaolinite in the red pigments from the Eireira barrow, and kaolinite in the white pigment from the Leira das Mamas barrow. The organic composition of the pigments was studied by GC–MS, suggesting that the red sinuous lines and dots from the Eireira barrow were prepared with cooked or heated algae and/or aquatic plants, with egg as binder, while the white pigment from the Leira das Mamas barrow revealed a mixture of vegetable oils for kaolinite moulding, which could be stabilized by temporary exposure to high temperatures. The multi‐analytical approach used on this study of megalithic pigments allowed the recovery of important data about north‐western prehistoric communities, namely the way in which they exploited existing resources and their ability to transform them.  相似文献   
995.
Archaeomagnetic dating based on the full geomagnetic field vector was carried out on a limekiln excavated at Pinilla del Valle archaeological site (Madrid, Spain). The limekiln tradition in this area is largely documented by historical sources for recent centuries but the date of the studied kiln's last use was unknown. The combination of mean archaeomagnetic directional and absolute archaeointensity results shows that the kiln was last used between ad 1296 and 1413, in good agreement with two independent radiocarbon dates. This study provides the first archaeomagnetic evidence that the local limekiln tradition dates back to at least late medieval times. Furthermore, the inclusion of these data in the Iberian secular variation curve and geomagnetic field models will help to improve the archaeomagnetic dating technique.  相似文献   
996.
Hair and bone samples procured from the remains of Tycho Brahe were analysed by several analytical techniques. In segmented hair samples, concentrations of Fe, As, Ag and Au at the tips exceeded values for the contemporary population; however, they decreased towards the hair bulbs, similarly to Hg, indicating that recent exposure that was discontinued ~2 months prior to Brahe's death. Several other elements did not follow this pattern. Analyses of bones revealed signs of long‐term exposure to Au, while many other elements were within expected ranges. Histopathological examination of bone sections yielded no signs of severe bone metabolic disorders.  相似文献   
997.
The present work aims to analyse the magnetic signature from the Late Holocene open‐air archaeological deposits of hunter–gatherer ephemeral occupations. For this purpose, two profiles were sampled at the Marazzi 2 site in the north‐western Isla Grande de Tierra del Fuego, Chile, in order to carry out studies of magnetic susceptibility, hysteresis cycles, back‐field remanent magnetization, isothermal remanent magnetization and thermal variation of magnetic susceptibility at high and low temperature. Despite short‐term occupations, the P1 profile shows a magnetic peak at a depth of ~30–70 cm due to magnetite, probably formed by anthropogenic activity related to combustion. The P2 profile instead yields an anomalous peak of coercivity (at a depth of 20–40 cm), which could also be anthropogenic, due to the presence of finely dispersed ancient ‘red ochre’. The red ochre is proposed to form anthropogenic thermal alteration of goethite associated with volcanic ash, the remnants of which were found in thin sections from the P2 subsoil.  相似文献   
998.
This article considers current proposals for using electronic payments systems to promote financial inclusion — that is, to widen the availability of financial and monetary services in developing countries. While such systems can generate significant savings in the operation of monetary systems, payment services markets are typically uncompetitive and require regulatory and broader state interventions to ensure those savings are widely distributed. The use of those systems to broaden the reach of for‐profit lenders raises a number of concerns, as a growing literature has documented how microcredit initiatives in developing countries have resulted primarily in expansions in consumption credit to households, often under predatory terms. The authors advance two original arguments in this connection. First, the perverse results of many microcredit initiatives reflect the underdevelopment of the areas concerned: without broader development strategies, potentially transformative productive projects are rare and unprofitable to finance. In contrast, widespread unmet consumption needs ensure consumption credit offers lenders a profitable alternative business orientation. Second, and in light of this, electronic payments platforms can contribute to economic development by enabling the establishment of well‐regulated or public systems of electronic ‘narrow banks’ restricted from lending, but capable of widening access to affordable payments, savings and insurance services.  相似文献   
999.
1000.
Jakob Löfgren 《Folklore》2017,128(1):75-92
This article examines the use of staged narratives in the Hogswatch celebration—a celebration of Terry Pratchett’s fictional Discworld held in November in Wincanton, Somerset. Different narratives are used in fandom as part of the process of qualia resituation, in which the what-it-is-like of the Discworld series is conveyed in the fandom celebration.  相似文献   
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