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11.
Detailed cathodoluminescence (CL) imaging of zircon crystals, coupled with Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICP-MS) U-Pb zircon dating was used to develop new insights into the evolution of granitoids from the High Tatra Mountains. The zircon U-Pb results show two distinct age groups (350±5 Ma and 337±6 Ma) recorded from cores and rims domains, respectively. Obtained results point that the last magmatic activity in the Tatra granitoid intrusion occurred at ca. 330 Ma. The previously suggested age of 314 Ma reflects rather the hydrothermal activity and Pb-loss, coupled with post-magmatic shearing.  相似文献   
12.
This paper explores some of the consequences of using archival materials produced by an anthropologist's informants. What happens when a resident from a rural area of Cuba is hired to write about the “world”, a term used by Carl L. Withers, in which he, his relatives and his neighbours live? By reading letters and other papers sent during the late 1940s, and kept by Withers for more than thirty years, my hypothesis is that his informants took seriously their capacity to create something other than a simple “testimony”. Withers's principal informant, created himself, his neighbours, strange beings and the world in which they cohabited as a certain type of artefact, as “data”.  相似文献   
13.
Two Early Devonian gastropod genera, Garraspira gen. nov. and Anoriostoma from the GarraLimestone, with sinistrally heterostrophic shells, share several shell features and are placed in the new tribe Anoriostomatini within the subfamily Agnesiinae. In contrast to the other members of the latter subfamily these genera represent a lineage in which the apertural slit was lost during evolution. This fact supports the opinion that the presence or absence of the apertural slit does not necessarily have significance for high-level taxonomy. Morphology of the gerontic whorl in Anoriostoma sinistra and Garraspira imtsitata suggests their limited mobility during the last ontogenetic stage.  相似文献   
14.
Considering the likely unfavorable behavior under seismic action of adobe construction, this article aims at providing a seismic fragility characterization of two adobe Portuguese traditional buildings, using numerical models calibrated over experimental results. The study of such two case-study buildings in the region of Aveiro contributes to the understanding of the seismic fragility of adobe construction in the region in general. The buildings were numerically modeled to estimate their structural behavior under seismic loading using adobe material properties that were calibrated based on the experimental results of a cyclic in-plane test of a full-scale double-Tshaped adobe wall. The method chosen to characterize adobe masonry and model its nonlinear behavior followed a total strain crack-based macro-modeling (TSCM) approach, whereas pushover analysis was carried out to reproduce the pseudo-static experimental test in order to enable a refined calibration of adobe masonry mechanical properties. Fragility functions were then derived, based on the above-mentioned numerical models, using nonlinear static analysis, bringing further insight on the seismic fragility of traditional Portuguese adobe construction.  相似文献   
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16.
The most common indicator used to measure spatial dependence is Moran's I proposed by statistician Patrick A. P. Moran in 1950. The index is simple to use and applies the principle of the Pearson correlation coefficient, although it incorporates a proximity measure between elements. However, Moran's I tends to underestimate real spatial autocorrelation when the number of locations are few. This study aims to present a modified version of Moran's I that can measure real spatial autocorrelation even with small samples and check for spatial dependence.  相似文献   
17.
In the second half of the nineteenth century Portugal undertook an ambitious public works programme in order to develop the kingdom. In that programme, railways took a leading role, especially those routes that linked the main ports of the shoreline to Spain (and thence to France). To do so, a strenuous effort of diplomacy – or more specifically technodiplomacy – was required to convince Spain to accept cross-border links that served the goals of Portugal. In this paper I will analyse this technodiplomatic process and how two countries with different technological perceptions of railways managed to settle their differences and build five transnational links across their borders over the course of 40 years. I aim to add to the debate about the Iberian cross-border links from the point of view of the history of technology, in particular, and to the discussion about transnational technological systems, in general.  相似文献   
18.
The paper discusses how the recent history of famine has influenced the mission of relief-oriented non-governmental organisations (NGOs).  相似文献   
19.
This paper provides evidence about location and colocation patterns of manufacturing entrepreneurship and spatial scope of agglomeration economies in the context of a developing country. Using microgeographic data for all Brazilian manufacturing activities and distance-based measures, we find clear patterns of colocalization between entrants and existing establishments, and that these patterns occur mainly at short distances. For activities presenting colocalization between entrants and existing establishments, our results also indicate that a greater number of incumbent establishments in a given location positively affects the number of entrant establishments that decide to locate there, an effect that attenuates rapidly with distance (generally disappearing after 5 km). This pattern of attenuation is robust to both the inclusion of a comprehensive set of controls for observable and unobservable local characteristics and the use of instrumental variables to address remaining endogeneity concerns.  相似文献   
20.
Abstract

Surpassing the national perspective usually adopted, the authors confirmed the existence of a pattern of population distribution common to the whole Iberian Peninsula in the long run. This pattern is clearly associated with geographical factors. These variables seem to have more weight in explaining changes between 1877/78 and 1940 than in the period from 1940 to 2001. The observation of the cross-border region has shown that proximity to the frontier has not generated any distinct pattern of population density on either side of the boundary line. The spatial coherence of the observed phenomena throughout the Peninsula and of its evolution, independent of the border between states, reinforces the importance of geographic factors in their explanation. At the same time, this verification opens up new issues related to the effect of national political and economic policies.  相似文献   
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