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We identified a SNP in the DPP6 gene that is consistently strongly associated with susceptibility to amyotrophic lateral sclerosis (ALS) in different populations of European ancestry, with an overall P value of 5.04 x 10(-8) in 1,767 cases and 1,916 healthy controls and with an odds ratio of 1.30 (95% confidence interval (CI) of 1.18-1.43). Our finding is the first report of a genome-wide significant association with sporadic ALS and may be a target for future functional studies.  相似文献   
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This paper compares various ways of extracting macroeconomic information from a data‐rich environment for forecasting the yield curve using the Nelson–Siegel model. Five issues in extracting factors from a large panel of macro variables are addressed; namely, selection of a subset of the available information, incorporation of the forecast objective in constructing factors, specification of a multivariate forecast objective, data grouping before constructing factors, and selection of the number of factors in a data‐driven way. Our empirical results show that each of these features helps to improve forecast accuracy, especially for the shortest and longest maturities. Factor‐augmented methods perform well in relatively volatile periods, including the crisis period in 2008–9, when simpler models do not suffice. The macroeconomic information is exploited best by partial least squares methods, with principal component methods ranking second best. Reductions of mean squared prediction errors of 20–30% are attained, compared to the Nelson–Siegel model without macro factors. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Climate change and population declines in a long-distance migratory bird   总被引:1,自引:0,他引:1  
Both C  Bouwhuis S  Lessells CM  Visser ME 《Nature》2006,441(7089):81-83
Phenological responses to climate change differ across trophic levels, which may lead to birds failing to breed at the time of maximal food abundance. Here we investigate the population consequences of such mistiming in the migratory pied flycatcher, Ficedula hypoleuca. In a comparison of nine Dutch populations, we find that populations have declined by about 90% over the past two decades in areas where the food for provisioning nestlings peaks early in the season and the birds are currently mistimed. In areas with a late food peak, early-breeding birds still breed at the right time, and there is, at most, a weak population decline. If food phenology advances further, we also predict population declines in areas with a late food peak, as in these areas adjustment to an advanced food peak is insufficient. Mistiming as a result of climate change is probably a widespread phenomenon, and here we provide evidence that it can lead to population declines.  相似文献   
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