Meta-analysis of type 2 Diabetes in African Americans Consortium

Type 2 diabetes (T2D) is more prevalent in African Americans than in Europeans. However, little is known about the genetic risk in African Americans despite the recent identification of more than 70 T2D loci primarily by genome-wide association studies (GWAS) in individuals of European ancestry. In order to investigate the genetic architecture of T2D in African Americans, the MEta-analysis of type 2 DIabetes in African Americans (MEDIA) Consortium examined 17 GWAS on T2D comprising 8,284 cases and 15,543 controls in African Americans in stage 1 analysis. Single nucleotide polymorphisms (SNPs) association analysis was conducted in each study under the additive model after adjustment for age, sex, study site, and principal components. Meta-analysis of approximately 2.6 million genotyped and imputed SNPs in all studies was conducted using an inverse variance-weighted fixed effect model. Replications were performed to follow up 21 loci in up to 6,061 cases and 5,483 controls in African Americans, and 8,130 cases and 38,987 controls of European ancestry. We identified three known loci (TCF7L2, HMGA2 and KCNQ1) and two novel loci (HLA-B and INS-IGF2) at genome-wide significance (4.15 × 10(-94)<P<5 × 10(-8), odds ratio (OR)  = 1.09 to 1.36). Fine-mapping revealed that 88 of 158 previously identified T2D or glucose homeostasis loci demonstrated nominal to highly significant association (2.2 × 10(-23) < locus-wide P<0.05). These novel and previously identified loci yielded a sibling relative risk of 1.19, explaining 17.5% of the phenotypic variance of T2D on the liability scale in African Americans. Overall, this study identified two novel susceptibility loci for T2D in African Americans. A substantial number of previously reported loci are transferable to African Americans after accounting for linkage disequilibrium, enabling fine mapping of causal variants in trans-ethnic meta-analysis studies.Peer reviewe

The LHCb upgrade I

The LHCb upgrade represents a major change of the experiment. The detectors have been almost completely renewed to allow running at an instantaneous luminosity five times larger than that of the previous running periods. Readout of all detectors into an all-software trigger is central to the new design, facilitating the reconstruction of events at the maximum LHC interaction rate, and their selection in real time. The experiment's tracking system has been completely upgraded with a new pixel vertex detector, a silicon tracker upstream of the dipole magnet and three scintillating fibre tracking stations downstream of the magnet. The whole photon detection system of the RICH detectors has been renewed and the readout electronics of the calorimeter and muon systems have been fully overhauled. The first stage of the all-software trigger is implemented on a GPU farm. The output of the trigger provides a combination of totally reconstructed physics objects, such as tracks and vertices, ready for final analysis, and of entire events which need further offline reprocessing. This scheme required a complete revision of the computing model and rewriting of the experiment's software

Demography of fluctuating populations: temporal and phase-related changes in vital rates of Microtus ochrogaster

1. Small mammal population fluctuations, cyclic or not, have been an ecological puzzle and a source of heated debate among ecologists. Identifying the demographic parameters that covary closely with density changes can help elucidate the underlying causes of population fluctuations, but few studies have reported rigorous estimates of these parameters. 2. We applied capture-mark-recapture analysis to twice-weekly trapping data from a long-term study of a fluctuating Microtus ochrogaster (prairie vole) population in Illinois, USA to estimate stage-specific apparent survival and maturation rates. We also estimated population density, fecundity rate, age at maturity and life span on a weekly basis. 3. Survival, maturation and fecundity rates exhibited phase-related changes during major density fluctuations, but they showed density-independent temporal variations during the prolonged low-density phases. Among these variables, maturation and juvenile survival rates covaried most closely with population density. 4. These results suggest that phase-related changes in maturation and juvenile survival rates are likely to be the main demographic factors driving the dynamics of our study population. 5. Phase-related changes in maturation rates provide a plausible demographic explanation of density fluctuations in our study population. Our results suggest that direct predation may not be necessary for large-scale fluctuations in M. ochrogaster abundance

Composição de gastrópodes terrestres em duas áreas do Centro de Estudos Ambientais e Desenvolvimento Sustentado (CEADS), Vila Dois Rios, Ilha Grande, Rio de Janeiro, Brasil: um estudo-piloto Composition of terrestrial gastropods in two areas of the Center to Environmental Studies and Sustainable Development (CEADS), Vila Dois Rios, Ilha Grande, Angra dos Reis, Rio de Janeiro, Brazil: a preliminary study

<abstract language="eng">A survey of the Ilha Grande land snails was carried out in order to compare the diversity and similarity among two regions of secondary Atlantic Rain Forest. The diversity was estimated using the richness and the equitatibility; the alpha diversity was calculated using the Simpson index (&#947;). The Sörensen and Jaccard indexes were used to calculate the similarity. A quantitative survey of two 600 m² area, one in each studied region, recorded 336 individuals snails distributed in 23 species and 13 families. The region with more altered secondary forest showed higher richness (17) and diversity (&#947; = 3,6) than the region more preserved (richness = 14; &#947; = 2,78), but, the same equitatibility (0,20). The similarity was medium by Jaccard index (IJ = 0,52) and low by Sorensen index (IS = 0,15). These differences could be explained by the dominance of Subulinidae (four species and 117 specimens) in the more altered region and Systrophiidae in the more preserved (four species and 97 specimens)