We scanned through the genomes of 29,141 African Americans, searching for loci where the average proportion of African ancestry deviates significantly from the genome-wide average. We failed to find ...any genome-wide significant deviations, and conclude that any selection in African Americans since admixture is sufficiently weak that it falls below the threshold of our power to detect it using a large sample size. These results stand in contrast to the findings of a recent study of selection in African Americans. That study, which had 15 times fewer samples, reported six loci with significant deviations. We show that the discrepancy is likely due to insufficient correction for multiple hypothesis testing in the previous study. The same study reported 14 loci that showed greater population differentiation between African Americans and Nigerian Yoruba than would be expected in the absence of natural selection. Four such loci were previously shown to be genome-wide significant and likely to be affected by selection, but we show that most of the 10 additional loci are likely to be false positives. Additionally, the most parsimonious explanation for the loci that have significant evidence of unusual differentiation in frequency between Nigerians and Africans Americans is selection in Africa prior to their forced migration to the Americas.
A workshop entitled "Internal Solitary Waves in the Ocean: Their Physics and Implications for Acoustics, Biology, and Geology" was held during October, 1998 in Sydney, British Columbia, Canada. It ...was jointly organized by the Woods Hole Oceanographic Institution (MA, USA), the Institute of Ocean Sciences, (Sydney, BC, Canada), and the U. S. Office of Naval Research. More than 60 scientists from seven countries attended. Participants contributed papers prior to the meeting which were published on the internet at the Woods Hole web site. Those papers are reproduced here.
Funding was provided by the Office of Naval Research under Contract Nos. N00014-95-1-0633 and N00014-99-1-0126.
This report summarizes the work of the "R-parity violation group" of the
French Research Network (GDR) in Supersymmetry, concerning the physics of
supersymmetric models without conservation of ...R-parity at HERA, LEP, Tevatron
and LHC and limits on R-parity violating couplings from various processes. The
report includes a discussion of the recent searches at the HERA experiment,
prospects for new experiments, a review of the existing limits, and also
theoretically motivated alternatives to R-parity and a brief discussion on the
implications of R-parity violation on the neutrino masses.
This report summarizes the work of the "R-parity violation group" of the French Research Network (GDR) in Supersymmetry, concerning the physics of supersymmetric models without conservation of ...R-parity at HERA, LEP, Tevatron and LHC and limits on R-parity violating couplings from various processes. The report includes a discussion of the recent searches at the HERA experiment, prospects for new experiments, a review of the existing limits, and also theoretically motivated alternatives to R-parity and a brief discussion on the implications of R-parity violation on the neutrino masses.
PDF
