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72.
Vallone, E.R., Vezzosi, R.I. & Cione, A.L. February 2017. First fossil fish (Teleostei, Siluriformes) from the Late Pleistocene of Santa Fe Province, Argentina. Alcheringa 00, 000–000. ISSN 0311-5518.

The record of fossil fish from the Pleistocene of Argentina is poor. Here we describe the first ichthyofauna from Late Pleistocene riverbank beds in the Salado River of Santa Fe Province, Argentina. The material consists of isolated pectoral and dorsal fin spines, together with skull fragments. Four species-level taxa referable to three families can be identified: Pterodoras granulosus (Doradidae), Pimelodus cf. maculatus and Pimelodus cf. albicans (Pimelodidae) and cf. Hypostomus sp. (Loricariidae). Specimens attributed to Pterodoras granulosus and Pimelodus maculatus represent a minimum age for origin of these taxa. The Salado River assemblage includes the richest record of Pleistocene catfishes yet documented from southern South America.

Evelyn Romina Vallone [] and Raúl Ignacio Vezzosi [], Laboratorio de Paleontología de Vertebrados, CICYTTP-CONICET, Materi y España, (3105) Diamante, Entre Ríos, Argentina; Alberto Luis Cione [], División Paleontología de Vertebrados. Museo de La Plata. Paseo del Bosque s/n, (1900) La Plata, Argentina.  相似文献   

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ABSTRACT

Removing barriers to labour mobility is expected to contribute to processes of spatial integration in cross-border regions, by an efficient allocation of labour and consequently a convergence between territories separated by a common border. Nevertheless, despite the de-bordering process within the European Union, administrative, legal and language barriers still hamper cross-border labour mobility, preventing the process of labour market integration. The aim of this paper is to identify obstacles to the mobility of cross-border workers commuting within the Euroregion Galicia–Norte de Portugal. The methodology employed combines the analysis of official data on labour mobility with qualitative data gathered from interviews with cross-border commuters, aimed at finding explanations for the different attitudes towards cross-border mobility inside this Euroregion. While traditional push and pull factors remain relevant in explaining cross-border labour flows, the qualitative information offers new insights into different levels of indifference from cross-border workers. The result is a fragmented labour market where Norte de Portugal is providing low-qualified, low-wage labour, whereas Galicia is contributing with well-paid, qualified labour.  相似文献   
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So far, the relationship between Industrial Districts (IDs; clusters of interconnected local industries) and migrant enclaves (areas with a high concentration of international migrants from a single nationality) has been studied mostly by focusing on the emergence of ‘ethnic enclave economies’ within the district and/or by highlighting racist conflicts that achieved notoriety in the media. In this study, we contend that there is a more general and complex interaction between the two phenomena. This interaction is mediated by the local context, national regulations, and the organization of the international market, among other factors. By focusing on the case of the ceramic ID of Castelló de la Plana (Spain), we show how this ID with a high rate of job formality, combined with other job opportunities and a unique ‘institutional completeness’, set up the conditions for a non-conflictive Romanian migrant enclave that reached 14% of the town’s total population in 2012. Finally, and also considering another case study of ID and migrant enclave (Prato, and its Chinese enclave), we suggest a model of interaction that should be interpreted taking into account the general dynamics of the international organization of value and the requirements of flexibility and reduction of costs that frame IDs.  相似文献   
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The highest platforms of As Laias, a settlement located in northwest Iberia, were used for storage during the Iron Age and until the turn of the Era. In this time-span, the whole hilltop – the croa – was a walled enclosure mostly used for storage and due to recurrent fires affecting the settlement's terraces, abundant plant remains were preserved in overlying wattle and daub storage structures.  相似文献   
77.
    
This article aims to highlight the main arguments that sought to justify the incorporation and legitimization of Urban Regeneration in the urban policy agenda in Brazil. It shows how the convergence between different and even conflicting propositions related to urban development provided ideological support to the construction of discourses in which urban regeneration is portrayed as beneficial to society as a whole, and how recent international ideas on urban development were incorporated in urban policies of contemporary Brazil, considering our local socio-economic and political environment, planning tradition and regulatory frameworks. The focus will be on Rio de Janeiro and particularly São Paulo given the key role these two cities play in defining urban policy paradigms, guiding government agendas and exporting regulatory models to other parts of Brazil.  相似文献   
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Teen employment is a very important socioeconomic phenomenon because of its consequences on human capital formation. We assess the relation between teen employment and poverty, education, and unemployment in the city of Rosario, using information from the 2010 Argentina Census disaggregated at census block level. We use two different spatial models: The spatial lag model (SLM) and a linear regression model with the spatial component filtered (filtering model, FM). Given the nature of the variables employed, multicollinearity is an issue. One of the techniques proposed in the literature to deal with multicollinearity problems is principal component regression (PCR). We develop an adaptation of such methodology to be used in the SLM. Both models are estimated using their traditional methodologies (instrumental variables for the SLM and OLS for the FM) and using PCR. Although results are similar between the two models, depending on the methodology used in the estimations they differ greatly. Under traditional methodologies estimations show high variability, instability, and contradictory outcomes, but under PCR, results behave according to the literature.  相似文献   
79.
    
ABSTRACT

Chemical residues preserved in floors can be considered anthropic activity markers. In fact, residues are strictly related to the activities performed and reflect their spatial distribution. We present a synthesis of the work carried out over the last few decades in Mexico and Italy related to the study of chemical residues in floors. Residues can be identified performing specific chemical analyses both of plastered or earthen floors samples. We outline a methodological approach concerning the use of the markers of the activities to interpret food production and consumption in the archaeological record, based upon evidence from experimental, ethnoarchaeological and archaeological examples. Here we point out the advantages and problems of such an approach, mainly related to equifinality, of the use of spot tests and gas chromatography coupled with mass spectrometry techniques using examples from different sites in the world.  相似文献   
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