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It has been amply demonstrated that individuals' reproductive capability is the key explanatory phenomenon for understanding onomastic disappearance during the early modern period. This article analyzes the evolution and consequences of surname extinction in a specific population: Catalonia in the sixteenth and seventeenth centuries. In this article two aspects are examined. First, the observed disappearance of surnames is estimated through historical data collected in the Llibres d'Esposalles (Marriage Books) from 1481 to 1600 at Barcelona Cathedral. Second, the estimated natural extinction of those surnames registered in 1481 is forecast by applying a statistical branching process.  相似文献   
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The objective of this research is to examine in depth the brokerage roles that supporting institutions play in conducting local business and applying technical knowledge inside clusters. We identify three main roles: a coordination role, characterized by the efforts that organizations play in internally coordinating themselves and establishing a shared institutional framework; an interconnector role, where organizations foster communication along the value chain of the industry; and a gatekeeper role that allows organizations to connect cluster members with external networks. Results obtained in the Toy Valley cluster provide evidence that each kind of supporting organization tends to specialize in specific roles, since universities are best for a coordination role with regard to technical knowledge while private organizations are key for vertical communication and coordination. Similar results were obtained when analysing the extra-cluster contacts that these organizations develop as gatekeepers, as they tend to establish specific communication conduits with similar alters in external networks.  相似文献   
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This paper introduces a special themed section that arose from an International Conference on Feminist Geographies and Intersectionality: Places, Identities and Knowledges, held in 2016 at the Universitat Autònoma de Barcelona. Six scholars of Canada, France, Greece, New Zealand, United Kingdom and United States seek to deal in five short papers with the intersectional dynamics of power structures and the central role of place within them. Here we situate the developments of intersectionality in feminist geographies in relation to the role of place and space in constituting intersectional relations, the relevance of context for the development of intersectionality and the use of different methodologies for research on it.  相似文献   
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This paper presents the results from extensive parametric dynamic analyses of soil-structure systems that focus on the clear modification (increase or decrease) of the acceleration amplitude at the foundation with respect to the free-field, especially for squatty structures. Properties of the systems are selected such as to cover a wide range of meaningful geometries and materials for engineering practice. The results are presented in terms of weighted modification factors of the maximum foundation acceleration amplitude with reference to the corresponding maximum acceleration amplitude at free-field, for squatty and more slender structures. For the large majority of the studied systems, foundation acceleration decreases from the free-field by 10–15% on average. Nevertheless, acceleration demand at the foundation increases compared to the free-field, for 30% of squatty and for 15% of the more slender structures. Modification of the foundation acceleration amplitude is also correlated with the ratio of the predominant period of the input motion to the flexible-base system period. Finally, the findings of this study are compared with sparse available recorded data from the Seismic Hazard Harmonization in Europe database.  相似文献   
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The seismic vulnerability of city centers is commonly assessed by extending the study methods applied to single buildings to urban aggregations. This approach is not always applicable at territorial scale, as it is uneconomical in terms of time and costs. An innovative method provides reasonable large-scale a priori estimation of parameters not directly evaluable from the exterior of buildings by elaborating values which can be measured from the outside. Those parameters are treated as continuous variables, by assigning them a suitable probability density function. The Bayesian approach is adopted, which allows the update of initial hypotheses by using new data gathered during on-site surveys. In this regard, a rapid survey form for the on-site data collection is proposed. An example of its application to a façade of a building structural unit in Santo Stefano di Sessanio in L’Aquila province (Italy) is proposed, showing promising preliminary results for buildings belonging to Italian historical centers.  相似文献   
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ABSTRACT

The employment of timber pegs in timber structure joints is a widespread technology in the field of timber frame building in the United States, where the Timber Frame Engineering Council has published a special Standard to supplement the National Design Specification for Wood Construction. The authors have been studying the possibility of supplementing the Eurocode 5 design formulas, thought for timber joints with metal connectors, with specifications needed for a reliable design when employing timber pegs. The field of application envisaged is that of restoring timber structures and results obtained until now are quite encouraging. In this step of the research, more attention has been paid to deformation process: fir and chestnut samples have been tested to determine their dowel-bearing behavior with steel and ash timber peg while double-shear plane joints made of the same wood species, and fastened with steel as well as timber pegs, have been analyzed.  相似文献   
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Quaternary stratigraphy and sea level changes have been extensively investigated in many areas of the Mediterranean. However, numerical dating of coastal deposits and the associated paleoenvironmental information are limited for the coasts of Cyprus, principally based on radiometric and radiation-exposure geochronological techniques on fossils which bear a range of limitations and uncertainties. As such, optically stimulated luminescence (OSL) dating techniques are deemed to be the most suitable in direct dating of the coastal sediments of Cyprus. In the southeastern Cyprus, coastal dunes (aeolianites) now forming elongated ridges appear as morphological features running parallel to the current shoreline presenting an indicator of sea level and climate changes of great paleoenvironmental significance. We present our first chronological results for the exposed aeolianites and underlying littoral deposits formed along the southeastern coastal Cyprus ranging from 78.4 ± 9.9 to 56.2 ± 7.4 ka. The post-infrared–infrared stimulated luminescence (pIR-IRSL) revealed that dune formation took place during the marine isotope stages (MISs) 3, 4, and possibly 5a. Late Holocene reworking is proposed for a distinctively isolated dune with an age of ~1.3 ka ago. This study also showed that pIR-IRSL dating of feldspars may be a reliable alternative to quartz OSL dating when the quartz luminescence characteristics are unsuitable.  相似文献   
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