Abstract: Identifying causative disease agents in human patients from shotgun metagenomic sequencing (SMS) presents a powerful tool to apply when other targeted diagnostics fail. Numerous technical challenges remain, however, before SMS can move beyond the role of research tool. Accurately separating the known and unknown organism content remains difficult, particularly when SMS is applied as a last resort. The true amount of human DNA that remains in a sample after screening against the human reference genome and filtering nonbiological components left from library preparation has previously been underreported. In this study, we create the most comprehensive collection of microbial and reference-free human genetic variation available in a database optimized for efficient metagenomic search by extracting sequences from GenBank and the 1000 Genomes Project. The results reveal new human sequences found in individual Human Microbiome Project (HMP) samples. Individual samples contain up to 95% human sequence, and 4% of the individual HMP samples contain 10% or more human reads. Left unidentified, human reads can complicate and slow down further analysis and lead to inaccurately labeled microbial taxa and ultimately lead to privacy concerns as more human genome data is collected.

Abstract: The production of the eta(c)(1S) state in protonproton collisions is probed via its decay to the p (p) over bar final state with the LHCb detector, in the rapidity range 2.0 < y < 4.5 and in the meson transverse-momentum range p(T) > 6.5GeV/c. The cross-section for prompt production of eta(c)(1S) mesons relative to the prompt J/psi cross-section is measured, for the first time, to be s sigma(eta c(1S))/sigma J/psi = 1.74 +/- 0.29 +/- 0.28 +/- 0.18(B) at a centre-of-mass energy root s = 7 TeV using data corresponding to an integrated luminosity of 0.7 fb(-1), and s sigma(eta c(1S))/sigma(J/psi) = 1.60 +/- 0.29 +/- 0.25 +/- 0.17(B) at root s = 8 TeV using 2.0 fb(-1). The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the (eta c)(1S) and J/psi decays to the p (p) over bar final state. In addition, the inclusive branching fraction of b-hadron decays into (eta c)(1S) mesons is measured, for the first time, to be B(b -> X-eta c) = (4.88 +/- 0.64 +/- 0.29 +/- 0.67(B)) x10(-3), where the third uncertainty includes also the uncertainty on the J/psi inclusive branching fraction from b-hadron decays. The difference between the J/psi and (eta c)(1S) meson masses is determined to be 114.7 +/- 1.5 +/- 0.1MeV/c(2).

Abstract: The short-range part of the neutrinoless double beta amplitude is generated via the exchange of exotic particles, such as charged scalars, leptoquarks and/or diquarks. In order to give a sizable contribution to the total decay rate, the masses of these exotics should be of the order of (at most) a few TeV. Here, we argue that these exotics could be the “light” (i.e., weak-scale) remnants of some B – L violating variants of SU(5). We show that unification of the standard model gauge couplings, consistent with proton decay limits, can be achieved in such a setup without the need to introduce supersymmetry. Since these nonminimal SU(5)-inspired models violate B – L, they generate Majorana neutrino masses and therefore make it possible to explain neutrino oscillation data. The light colored particles of these models can potentially be observed at the LHC, and it might be possible to probe the origin of the neutrino masses with Delta L = 2 violating signals. As particular realizations of this idea, we present two models, one for each of the two possible tree-level topologies of neutrinoless double beta decay.