21,015 research outputs found
Unification of Flavor SU(3) Analyses of Heavy Hadron Weak Decays
Analyses of heavy mesons and baryons hadronic charmless decays using the
flavor SU(3) symemtry can be formulated in two different forms. One is to
construct the SU(3) irreducible representation amplitude (IRA) by decomposing
effective Hamiltonian, and the other is to draw the topological diagrams (TDA).
In the flavor SU(3) limit, we study various ,
decays, and two-body nonleptonic decays of beauty/charm baryons, and
demonstrate that when all terms are included these two ways of analyzing the
decay amplitudes are completely equivalent. Furthermore we clarify some
confusions in drawing topological diagrams using different ways of describing
beauty/charm baryons.Comment: 36 pages, 6 figures, 16 table
Weak Decays of Doubly Heavy Baryons: Multi-body Decay Channels
The newly-discovered decays into the , but the experimental data has indicated that this decay is not
saturated by any two-body intermediate state. In this work, we analyze the
multi-body weak decays of doubly heavy baryons , ,
, , and , in particular the
three-body nonleptonic decays and four-body semileptonic decays. We classify
various decay modes according to the quark-level transitions and present an
estimate of the typical branching fractions for a few golden decay channels.
Decay amplitudes are then parametrized in terms of a few SU(3) irreducible
amplitudes. With these amplitudes, we find a number of relations for decay
widths, which can be examined in future.Comment: 47pages, 1figure. arXiv admin note: substantial text overlap with
arXiv:1707.0657
Sparse regression models for unraveling group and individual associations in eQTL mapping
BackgroundAs a promising tool for dissecting the genetic basis of common diseases, expression quantitative trait loci (eQTL) study has attracted increasing research interest. Traditional eQTL methods focus on testing the associations between individual single-nucleotide polymorphisms (SNPs) and gene expression traits. A major drawback of this approach is that it cannot model the joint effect of a set of SNPs on a set of genes, which may correspond to biological pathways.ResultsTo alleviate this limitation, in this paper, we propose geQTL, a sparse regression method that can detect both group-wise and individual associations between SNPs and expression traits. geQTL can also correct the effects of potential confounders. Our method employs computationally efficient technique, thus it is able to fulfill large scale studies. Moreover, our method can automatically infer the proper number of group-wise associations. We perform extensive experiments on both simulated datasets and yeast datasets to demonstrate the effectiveness and efficiency of the proposed method. The results show that geQTL can effectively detect both individual and group-wise signals and outperforms the state-of-the-arts by a large margin.ConclusionsThis paper well illustrates that decoupling individual and group-wise associations for association mapping is able to improve eQTL mapping accuracy, and inferring individual and group-wise associations.Electronic supplementary materialThe online version of this article (doi:10.1186/s12859-016-0986-9) contains supplementary material, which is available to authorized users
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