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51.
The discovery of a Neolithic Alpine jade axehead in Aroche, in the southwest of Spain, revives the question of long-distance exchange between the Iberian Peninsula and the rest of Europe. This polished blade belongs to a typological model quite characteristic of Alpine production during the second half of the 5th millennium B.C. Different mineralogical approaches (macroscopic features examination, specific gravity, direct XRD, non-destructive μXRF spectroscopy, optical stereomicroscopy, magnetic susceptibility determination and microprobe analysis) have identified the rock as an omphacitic jadeitite (mixed jade) with some tiny garnets and a weak retromorphosis. This analysis and the comparison of the rock structure with the referential JADE of Alpine natural jade samples, as well as the extraction modalities and shaping of the axe, provide strong arguments to assign the Aroche axe to a production of Mont Viso: the origin of thousands of axes that circulated in Europe between Ireland and Sicily. The Aroche axe, discovered not far from the variscite mines of Encinasola, could be considered as part of a possible exchange system between the Iberian Peninsula and the Gulf of Morbihan, in Brittany.  相似文献   
52.
We present the first full archaeometrical study of Kushan‐Sassanian pottery from the Buddhist monastic complexes at Kara Tepe (Termez, Uzbekistan), recovered both in the pottery workshop and in the monastery, using a combination of analytical methods (XRF, XRD, SEM–EDS and OM). The study allowed the identification of the reference group, the correspondent fabric, the raw materials used for its productions, some of the technological processes involved in manufacture and several weathering processes. All the results confirm that the kiln was supplying the religious community of the monastery with pottery, made using local raw materials, and highlight the possibility that the kiln could have supplied the nearby monastic complexes, where no kilns have been found. Further archaeological evidence indicates the existence of specialized potters working itinerantly at the broader Bactrian area.  相似文献   
53.
Ubilla, M. & Rinderknecht, A., April 2016. Lagostomus maximus (Desmarest) (Rodentia, Chinchillidae), the extant plains vizcacha in the Late Pleistocene of Uruguay. Alcheringa 40, xxx–xxx. ISSN 0311-5518

The extant plains vizcacha, Lagostomus maximus, is described from the Late Pleistocene (Dolores Formation) of Uruguay based on an almost complete articulated skeleton. It is compared with the nominally extinct Pleistocene species of the genus. An AMS 14C taxon-age is determined for L. maximus at 11 879 ± 95 years BP (cal. BP 13 898–13 941). Lagostomus maximus is absent from modern mammal communities in Uruguay, and no Holocene evidence is available. Because L. maximus exhibits remarkable sexual and ontogenetic dimorphism, we examined a range of juvenile, sub-adult and adult male and female specimens. It is not possible to differentiate the articulated Pleistocene fossil from sub-adult specimens of L. maximus based on this sample. Moreover, the skull characteristics, including a broad vertical ramus of the zygomatic arch, semi-circular temporal crest and short robust sagittal crest, most closely resemble extant female individuals. Molar size is non-predictive for ontogenetic stage or body mass because it reaches stability during early adulthood. Other fragmentary skull remains are herein assigned to L. sp. cf. L. maximus. Lagostomus cavifrons from the Pleistocene of Argentina is considered synonymous with L. maximus. Its character states concur with the range of intraspecific variability and it has been established on a young adult or adult male individual. Likewise, the other Argentinean Pleistocene species based on incomplete mandibles, L. angustidens, L. striatus, L. heterogenidens, L. egenus, L. minimus and L. debilis, concur with ontogenetic morphs and are here assigned to Lagostomus sp. The ecological preferences of extant L. maximus infer open arid or semi-arid landscapes for the latest Pleistocene of southern Uruguay. This hypothesis is reinforced by the coeval presence of Microcavia, Galea and small camelids in the same strata. The Last Glacial Maximum likely promoted this environmental setting. Latest Pleistocene or early Holocene climatic change might have facilitated local extinctions and/or range shifts among this mammal fauna.

Martín Ubilla [], Facultad de Ciencias, Universidad de la Republica, Iguá 4225, 11400, Montevideo, Uruguay; Andrés Rinderknecht [], Museo Nacional de Historia Natural, Paleontología, 11000, Montevideo, Uruguay.  相似文献   

54.
Squatting empty properties for living or to develop public activities has lasted in European cities for more than three decades. Although local and national contexts differ significantly, there are also some general trends and patterns that deserve careful attention. When squatting occasionally appears in public debates, controversy is generated and many gaps open between academic, social and political perceptions. In this article I use evidence from several European cities to argue that the squatters' movement has produced an original impact in urban politics. The main feature of this impact has been to generate a relatively wide autonomous and mainly non‐institutional mode of citizen participation, protest and self‐management. How has this been possible? Which are the specific contributions made by this urban movement? These are questions that both scholars and activists continuously claim to be relevant, so that this research attempts to offer some general answers based on detailed comparisons and experiences.  相似文献   
55.
The evolution of littoral palaeoenvironments in the southern Pampas region of Argentina towards the end of the early Holocene and the beginning of the mid Holocene is discussed, and the formation processes of the archaeological site of La Olla are analysed. This site is located in the intertidal zone of the present beach and is remarkably well-preserved. The human occupation at the site has been dated at between 7400 and 6480 yrs BP, and is interpreted as a place for the processing and consumption of the southern fur seal (Arctocephalus australis) and southern sea-lion (Otaria flavescens). It is concluded that biostabilization by microbial mats of the sedimentary structures and archaeological remains that developed and are present on the tidal flat prevented their erosion by wind, turbulence currents and waves. This is what has permitted the exceptional preservation of the site. On the basis of the analyses of one of the sectors of the site it can be concluded that the sedimentary succession of the La Olla site is the result of the coastal environmental changes during the early–mid Holocene in the pre-maximum transgressive episode. During this interval a tidal flat developed on the Pleistocene abrasion platform. Human occupation occurred during the formation of mixohaline marsh, an upper intertidal–lower supratidal zone ecosystem.  相似文献   
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57.
The pattern of Latin American Boom criticism developed by Donald L. Shaw established that Juan Rulfo's protagonists are universal, not regional. In this interpretative mode, espoused by Graciela B. Coulson and others, Rulfo's characters are viewed as powerless to alter their own destinies. Humans are dominated and doomed by the hostile natural world that surrounds them. However, through a detailed analysis of Rulfo's technique and the internal and external structure of two of Rulfo's short stories in El llano en llamas—“No oyes ladrar a los perros” and “Es que somos muy pobres”—a new theoretical framework emerges for the study of Rulfo's work. In these two stories, Rulfo imagines the llano as a space that individuals control through their personal choices and actions. This article proposes, therefore, that Rulfo's protagonists are not victims of their environment, but rather the perpetrators of its violence.  相似文献   
58.
The degradation of marine and coastal ecosystems has given rise to the creation of specific protection rules. The Marine Strategy Framework Directive and the Water Framework Directive are the standards agreed in the European Union with the aim of obtaining a good ecological status in marine and coastal waters by applying a programme of measures, if necessary. These measures must be technical, social and economically feasible, in such a way that costs do not exceed benefits. This work expounds the implementation of two economic tools to assess the programme of measures intended for the environmental restoration of one of the most important coastal ecosystems in Europe, the Mar Menor coastal lagoon (SE Spain). Thus, the cost–benefit analysis (CBA) (and its extensions) and the contingent valuation method are used to assess the aforementioned programme in terms of economic and environmental profitability. Results prove the socioeconomic and environmental profitability of the actions due to be undertaken, with rates of return of around 10%. From a methodological point of view, there is a clear need to widen the classic CBA scheme by using the extended CBA and the dual CBA to gauge this type of environmental restoration actions.  相似文献   
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60.
We synthesize and discuss available isotopic data on Holocene guanaco samples from southern South America, extending from Tierra del Fuego Island to northern Patagonia and the Pampean region. We evaluate temporal and spatial tendencies on the basis of 91 samples (mainly based on δ13Ccollagen values), presenting implications for paleodietary research in archaeology. We conclude that there are no strong correlations with latitude in the macro-spatial scale, while there is a set of interesting patterns at smaller regional scales. These patterns lead us to evaluate the role of ecologic and topographic variables (e.g. canopy effect, variations in altitude, ecotones) in structuring isotopic variability. Finally, on the basis of the present analysis we suggest a number of hypotheses and perspectives for the use of stable isotopes as geographic tracers of guanaco distribution in the past, and specific implications for the paleodietary study of human samples.  相似文献   
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