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41.
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   

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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   
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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   
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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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This article describes the important discovery of a Late Bronze Age gold torc that was unearthed in a field of Acehúche (Cáceres, Spain). It was buried underneath some rocks at a site near a river crossing over the Tagus river. In its immediate vicinity, archaeological remains dating from the Copper Age to the Late Bronze Age have been found, which indicates the long use of this crossing. Until recently here, there existed a ferry and a chapel; and the place went by the toponym of the Dehesa de San Cristóbal. Legend too has it that the water from the river had curative properties. All of these components have maintained the sacred nature of the spot, otherwise transformed over the course of time, and reflect an earlier sacred landscape with quite ancient roots.  相似文献   
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Sociological models of place-based identity can be used to better understand the social dynamics of local communities and how they interact with their surroundings. This paper explores how these theoretical models of belonging to a place, in tandem with communal cognitive maps, can be applied to post-Roman contexts, taking the Iberian Peninsula in the Visigothic period (sixth–eighth centuries) as a preliminary case study. We argue that this approach can give us not only a more complex understanding of community agencies but also allows us to reconsider the social context for past social interactions. Furthermore, it will open a new archaeological perspective for future work on the relations between groups and individuals with their built, social, and natural environments.  相似文献   
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