28 resultados para Crash Predictions

em BORIS: Bern Open Repository and Information System - Berna - Suiça


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We present a geospatial model to predict the radiofrequency electromagnetic field from fixed site transmitters for use in epidemiological exposure assessment. The proposed model extends an existing model toward the prediction of indoor exposure, that is, at the homes of potential study participants. The model is based on accurate operation parameters of all stationary transmitters of mobile communication base stations, and radio broadcast and television transmitters for an extended urban and suburban region in the Basel area (Switzerland). The model was evaluated by calculating Spearman rank correlations and weighted Cohen's kappa (kappa) statistics between the model predictions and measurements obtained at street level, in the homes of volunteers, and in front of the windows of these homes. The correlation coefficients of the numerical predictions with street level measurements were 0.64, with indoor measurements 0.66, and with window measurements 0.67. The kappa coefficients were 0.48 (95%-confidence interval: 0.35-0.61) for street level measurements, 0.44 (95%-CI: 0.32-0.57) for indoor measurements, and 0.53 (95%-CI: 0.42-0.65) for window measurements. Although the modeling of shielding effects by walls and roofs requires considerable simplifications of a complex environment, we found a comparable accuracy of the model for indoor and outdoor points.

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In addition to the increasingly significant role of multislice computed tomography in forensic pathology, the performance of whole-body computed tomography angiography provides outstanding results. In this case, we were able to detect multiple injuries of the parenchymal organs in the upper abdomen as well as lesions of the brain parenchyma and vasculature of the neck. The radiologic findings showed complete concordance with the autopsy and even supplemented the autopsy findings in areas that are difficult to access via a manual dissection (such as the vasculature of the neck). This case shows how minimally invasive computed tomography angiography can serve as an invaluable adjunct to the classic autopsy procedure.

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Releasing captive-bred fish into natural environments (stocking) is common in fisheries worldwide. Although stocking is believed to have a positive effect on fish abundance over the short term, little is known about the long-term consequences of recurrent stocking and its influence on natural populations. In fact, there are growing concerns that genetically maladapted captive-bred fish can eventually reduce the abundance of natural population. In this study, we develop a simple model to quantitatively investigate the condition under which recurrent stocking has long-term effects on the natural population. Using a population dynamics model that takes into account a density-dependent recruitment, a gene responsible for the fitness difference between wild and captive-bred fish, and hybridization between them, we show that there is little or no contribution of recurrent stocking to the stock enhancement without a replacement of the wild gene pool by the captive-bred gene pool. The model further predicted that stocking of an intermediate level causes a reduction, rather than enhancement, of population size over the long term. The population decline due to stocking was attributed to the fitness disadvantage of captive-bred fish and strong overcompensation at recruitment stage. These results suggest that it would be difficult to simultaneously attain population size recovery and conservation of the local gene pool when captive-bred fish have fitness disadvantage in the wild, although caution is needed when applying the predictions from the simplified model to a specific species or population.

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When high-energy single-hadron production takes place inside an identified jet, there are important correlations between the fragmentation and phase-space cuts. For example, when one-hadron yields are measured in on-resonance B-factory data, a cut on the thrust event shape T is required to remove the large b-quark contribution. This leads to a dijet final-state restriction for the light-quark fragmentation process. Here, we complete our analysis of unpolarized fragmentation of (light) quarks and gluons to a light hadron h with energy fraction z in e+e−→dijet+h at the center-of-mass energy Q=10.58  GeV. In addition to the next-to-next-to-leading order resummation of the logarithms of 1−T, we include the next-to-leading order nonsingular

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Aims Floral traits are frequency used in traditional plant systematics because Of their assumed constancy. One potential reason for the apparent constancy of flower size is that effective pollen transfer between flowers depends oil the accuracy of the physical fit between the flower and pollinator. Therefore, dowels are likely to he under stronger stabilizing selection for uniform size than vegetative plant parts. Moreover, as predicted by the pollinator-mediated stabilizing selection (PMSS) hypothesis, all accurate fit between flowers and their pollinators is likely to he more important for specialized pollination systems as found in many species with bilaterally symmetric (zygomorphic) flowers than for species, with radially symmetric (actinomorphic) flowers. Methods In a comparative study of 15 zygomorphic and 13 actinomorphic species ill Switzerland, we tested whether variation in flower size, among and within individuals, is smaller than variation ill leaf size and whether variation in flower size is smaller ill zygomorphic compared to actinomorphic species. Important findings Indeed, variation ill leaf length was significantly larger than variation in flower length and width. Within-individual variation ill flower and leaf sizes did not differ significantly between zygomorphic and actinomorphic species. In line with the predictions of the PMSS, among-individual variation ill flower length and flower width was significantly smaller for zygomorphic species than for actinomorphic species, while the two groups did not differ in leaf length variation. This suggests that plants with zygomorphic flowers have undergone stronger selection for uniform flowers than plants with actinomorphic flowers. This supports that the uniformity of flowers compared to vegetative structures within species, as already observed in traditional plant systematics, is, at least in part, a consequence of the requirement for effective pollination.