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11.
In the context of modeling regional freight the four‐stage model is a popular choice. The first stage of the model, freight generation and attraction, however, suffers from three shortcomings: first of all, it does not take spatial dependencies among regions into account, thus potentially yielding biased estimates. Second, there is no clear consensus in the literature as to the choice of explanatory variables. Second, sectoral employment and gross value added are used to explain freight generation, whereas some recent publications emphasize the importance of variables which measure the amount of logistical activity in a region. Third, there is a lack of consensus regarding the functional form of the explanatory variables. Multiple recent studies emphasize nonlinear influences of selected variables. This article addresses these shortcomings by using a spatial variant of the classic freight generation and attraction models combined with a penalized spline framework to model the explanatory variables in a semiparametric fashion. Moreover, a Bayesian estimation approach is used, coupled with a penalized Normal inverse‐Gamma prior structure, to introduce uncertainty regarding the choice and functional form of explanatory variables. The performance of the model is assessed on a real‐world example of freight generation and attraction of 258 European NUTS‐2 level regions, covering 25 European countries.  相似文献   
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This paper examines skeletal and ancient DNA evidence in the study of suspected tuberculosis infection in the late pre-Hispanic and Colonial-era Lambayeque Valley Complex, north coast Peru (A.D. 900–1750). We integrate information on macroscopic lesion characteristics and distribution, radiographic and CT scan imagery, and analysis of Mycobacterium tuberculosis complex rpoB and IS6110 ancient DNA (aDNA) sequences. Destructive lesions were observed in the vertebral bodies of three precontact indigenous adult males, one colonial adolescent female, and in the cranium of a Colonial-period subadult. Assessment of lesion morphology and distribution led us to consider multiple diseases, but tuberculosis represents the most likely diagnostic option in all individuals. DNA was poorly preserved in all samples, but an IS6110 sequence was amplified in one precontact individual consistent with macroscopic diagnosis. These findings expand the geographic and temporal extent of tuberculosis to the late pre-Hispanic and Colonial north coast of Peru to highlight potential synergisms between diet, settlement patterns, and the evolution of Andean tuberculosis before and after European conquest. Moreover, this study helps focus several key questions in Andean tuberculosis research, including possible reassessment of the presence of the IS6110 sequence in the pre-Columbian Americas. Methodological considerations include differential diagnosis – especially with incomplete skeletons – and limitations of aDNA studies underscoring an approach integrating macroscopic, radiographic, and molecular lines of evidence in the paleopathological investigation of one of humankind’s most devastating and destabilizing diseases.  相似文献   
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Ground motions recorded in the epicentral region of an earthquake often have a strong vertical component with dominant high frequencies. Damage to bridges in near-source regions due to strong vertical ground motion has been reported. The beneficial effects of footing uplift on structural performance in form of reduction of seismic response of structural members have been confirmed in previous research. The uplift of bridge piers has been utilised in a very limited number of bridge structures, e.g., the South Rangitikei railway bridge in New Zealand. However, the near-fault seismic behaviour of bridges with footing uplift has been even less addressed. In this study shake table investigations were carried out on the response of a single-span bridge model with footing uplift subjected to simultaneous vertical and horizontal excitations. Near-fault ground motions recorded in the Canterbury earthquake sequences of 2010 and 2011 were used. The experimental results show that inclusion of vertical ground motions produce stronger axial force in the pier and larger bending moment in the deck. Concurrent horizontal and vertical excitations may also cause more frequent footing uplift than the solely horizontal excitations.  相似文献   
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For many policy considerations it is assumed that the convergence of regional mean income will improve national equity by reducing overall inequality. The literature on decomposability of social welfare functions implies that this assumption is unwarranted. This paper develops a notion of optimal regional convergence. In general, the point of optimal convergence depends on the shapes of the regional income distributions, the inequality index used, and the rule for distributing interregional transfers. These concepts are illustrated with data on the regional income distributions of the Southern and Northern United States.  相似文献   
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During an excavation of a Bronze Age, Füzesabony-culture cemetery at Encs (north-eastern Hungary), a clay wagon model with spoked wheels (grave 1290) and three miniature solid clay wheels were found (grave 1389). Miniature wagon and wheel models in burials began to appear in the Late Copper Age and lasted until the Iron Age in Central Europe. Their presence allows of several interpretations. These spoked wheels of grave 1290 provide early evidence about the appearance of such in the Carpathian Basin. Focussing on the two graves from Encs, this article reports AMS radiocarbon dates that suggest the spoked wheels belong to the early second millennium BC. The implications of these finds are interpreted though a comparative review of both wagon models from the Füzesabony culture and the evidence for early spoked wheels in the Carpathian Basin.  相似文献   
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