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Selected AbstractsEffects of beverage alcohol price and tax levels on drinking: a meta-analysis of 1003 estimates from 112 studiesADDICTION, Issue 2 2009Alexander C. Wagenaar ABSTRACT Aims We conducted a systematic review of studies examining relationships between measures of beverage alcohol tax or price levels and alcohol sales or self-reported drinking. A total of 112 studies of alcohol tax or price effects were found, containing1003 estimates of the tax/price,consumption relationship. Design Studies included analyses of alternative outcome measures, varying subgroups of the population, several statistical models, and using different units of analysis. Multiple estimates were coded from each study, along with numerous study characteristics. Using reported estimates, standard errors, t -ratios, sample sizes and other statistics, we calculated the partial correlation for the relationship between alcohol price or tax and sales or drinking measures for each major model or subgroup reported within each study. Random-effects models were used to combine studies for inverse variance weighted overall estimates of the magnitude and significance of the relationship between alcohol tax/price and drinking. Findings Simple means of reported elasticities are ,0.46 for beer, ,0.69 for wine and ,0.80 for spirits. Meta-analytical results document the highly significant relationships (P < 0.001) between alcohol tax or price measures and indices of sales or consumption of alcohol (aggregate-level r = ,0.17 for beer, ,0.30 for wine, ,0.29 for spirits and ,0.44 for total alcohol). Price/tax also affects heavy drinking significantly (mean reported elasticity = ,0.28, individual-level r = ,0.01, P < 0.01), but the magnitude of effect is smaller than effects on overall drinking. Conclusions A large literature establishes that beverage alcohol prices and taxes are related inversely to drinking. Effects are large compared to other prevention policies and programs. Public policies that raise prices of alcohol are an effective means to reduce drinking. [source] Association tests using kernel-based measures of multi-locus genotype similarity between individualsGENETIC EPIDEMIOLOGY, Issue 3 2010Indranil Mukhopadhyay Abstract In a genetic association study, it is often desirable to perform an overall test of whether any or all single-nucleotide polymorphisms (SNPs) in a gene are associated with a phenotype. Several such tests exist, but most of them are powerful only under very specific assumptions about the genetic effects of the individual SNPs. In addition, some of the existing tests assume that the direction of the effect of each SNP is known, which is a highly unlikely scenario. Here, we propose a new kernel-based association test of joint association of several SNPs. Our test is non-parametric and robust, and does not make any assumption about the directions of individual SNP effects. It can be used to test multiple correlated SNPs within a gene and can also be used to test independent SNPs or genes in a biological pathway. Our test uses an analysis of variance paradigm to compare variation between cases and controls to the variation within the groups. The variation is measured using kernel functions for each marker, and then a composite statistic is constructed to combine the markers into a single test. We present simulation results comparing our statistic to the U -statistic-based method by Schaid et al. ([2005] Am. J. Hum. Genet. 76:780,793) and another statistic by Wessel and Schork ([2006] Am. J. Hum. Genet. 79:792,806). We consider a variety of different disease models and assumptions about how many SNPs within the gene are actually associated with disease. Our results indicate that our statistic has higher power than other statistics under most realistic conditions. Genet. Epidemiol. 34: 213,221, 2010. © 2009 Wiley-Liss, Inc. [source] Spatio-temporal variation of avian foraging in the rocky intertidal food webJOURNAL OF ANIMAL ECOLOGY, Issue 1 2001Masakazu Hori Abstract 1While birds are top predators in most rocky intertidal communities, the relationship between foraging pattern and variability in food web structure has not been studied. This study examined the spatio-temporal variation of both avian foraging and food web structure at an intertidal rocky shore in northern Japan over a 1-year period. 2Seventeen bird species foraged on the intertidal rocky shore. Crows and gulls were dominant, and their major prey was sea urchins that migrated from the sub-tidal to intertidal habitat. Interspecific interactions (i.e. stealing of food, utilization of food waste by other species) occurred between crows and gulls especially when feeding on sea urchins. The prey of the birds showed spatial and temporal partitioning. 3The number of prey items consumed per day by the dominant birds varied with various factors. Factors strongly affecting the foraging pattern of crows were waves, tides, humans and gulls, and those strongly affecting the foraging pattern of gulls were tides, humans, sea urchins and crows. 4In the rocky intertidal food web, most of the top predators were birds, and most of the birds were omnivores. The birds consumed many more species than did other consumers. Food-resource partitioning caused spatio-temporal compartmentation among subwebs in which the top predators were dominant birds. 5Analysis of food web statistics (i.e. web size, numbers of links, linkage density, chain lengths) revealed that the presence/absence of birds did not change the relationships between web size and the other statistics. The food web statistics depended on web size, and the web size was positively related with time spent emersed and temperature when birds were both present and not present. 6Birds often foraged across habitat boundaries, and the main food resource of top predators was the prey species from the subtidal habitat. Therefore, the spatial scale of the Hiura rocky intertidal food web temporally varied with birds foraging across habitat boundaries. [source] Scaling turbulent atmospheric stratification.THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 631 2008II: Spatial stratification, intermittency from lidar data Abstract We critically re-examine existing empirical studies of vertical and horizontal statistics of the horizontal wind and find that the balance of evidence is in favour of the Kolmogorov kx,5/3 scaling in the horizontal, Bolgiano-Obukov scaling kz,11/5 in the vertical corresponding to a Ds = 23/9 stratified atmosphere in (x, y, z) space. This interpretation is particularly compelling once one recognizes that the 23/9-D turbulence can lead to long-range biases in aircraft trajectories and hence to spurious statistical exponents in wind, temperature and other statistics reported in the literature. Indeed, we show quantitatively that one is easily able to reinterpret the major aircraft-based campaigns (GASP, MOZAIC) in terms of the model. In part I, we have seen that this model is compatible with ,turbulence waves' which can be close to classical linear gravity waves in spite of their very different nonlinear mechanism. We then use state-of-the-art lidar data of atmospheric aerosols (considered as passive tracers) in order to obtain direct estimates of the effective (,elliptical') dimension of the spatial part: Ds = 23/9 = 2.55 ± 0.02. This result essentially rules out the standard 3-D or 2-D isotropic theories or the anisotropic quasi-linear gravity wave theories which have Ds = 3, 2, 7/3 respectively. In this paper we focus on the multifractal (intermittency) statistics showing that there is a very small but apparently real variation in the value of Ds, ranging for the weak and intense structures so that Ds ranges from roughly 2.53 to 2.57. We also show that the passive scalars are well approximated by universal multifractals; we estimate the exponents to be ,h = 1.82 ± 0.05, ,v = 1.83 ± 0.04, C1h = 0.037 ± 0.0061 and C1v = 0.059 ± 0.007 (h for horizontal, v for vertical). Copyright © 2008 Royal Meteorological Society [source] Genetic variation in Irish pygmy shrews Sorex minutus (Soricomorpha: Soricidae): implications for colonization historyBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2009ALLAN D. MCDEVITT The status of the pygmy shrew (Sorex minutus L.) as a native or an introduced species in Ireland has been subject to much debate. To examine this and other aspects of the colonization history of the Irish pygmy shrew, genetic variation was determined in 247 pygmy shrews collected throughout Ireland, using mitochondrial control region sequences and five polymorphic microsatellite loci. Genetic diversity was low for both types of marker. The median-joining network for control region sequences was star-like, suggesting that the colonization of Ireland involved a small number of founders and rapid population expansion thereafter; this was supported by other statistics. Molecular dating with both mitochondrial DNA and microsatellite data is consistent with a human introduction. This would have been several thousand years ago; a recent colonization within historical times can be ruled out. This is the first detailed population genetic study of the pygmy shrew anywhere in its range. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 918,927. [source] |