Colour Reconnection at LEP

Two measurements are presented of estimators sensitive to the Colour Reconnection effect in WW events at LEP2. The results are compared with various phenomenological Monte Carlo implementations of the effect. A feasibility study is performed to reduce the total uncertainty in the direct W boson mass measurement at LEP2 by use of the inferred information about the Colour Reconnection effect.Comment: Proceeding of the EPS Conference on HEP, Aachen 200

Top Quark Physics at the LHC

The Large Hadron Collider (LHC) is expected to provide proton-proton collisions at a centre-of-mass energy of 14 TeV, yielding millions of of top quark events. The top-physics potential of the two general purpose experiments, ATLAS and CMS, is discussed according to state-of-the-art simulation of both physics and detectors. An overview is given of the most important results with emphasis on the expected improvements in our understanding of physics connected to the top quark

The effectiveness of a fundamental motor skill intervention in pre-schoolers with motor problems depends on gender but not environmental context

This study evaluated the effect of a 10-week fundamental motor skill programme in pre-schoolers with motor problems. Alongside the general effect of the intervention, we also explored possible gender differences and the role of the environmental context (living community, socio-economic status, and recreational space inside/outside the house). The intervention group (n=47; 20 ♂ and 27 ♀) received twenty 60-min motor skill sessions (2 per week) in addition to the regular physical education curriculum for pre-schoolers; the control group (n=46; 21 ♂ and 25 ♀) did not receive additional practice. General motor competence, and locomotor and object control subscales, were assessed before and after the intervention using the Test of Gross Motor Development 2nd edition (TGMD-2). Data regarding environmental factors were gathered through a questionnaire. A Group×Gender×Time ANOVA revealed that the intervention group benefited significantly from the intervention and scored better than the control group at the post-test for general motor competence and both sub-categories (locomotor and object control skill). Moreover, the intervention programme was found to be effective in helping 49% of the intervention group to achieve an average motor skill level, according to the TGMD-2 norms, while a further decline in motor competence was observed in the control group. Interestingly, the effect appeared to be gender-specific, since object control skill improved only in girls of the intervention group. Considering the environmental context, none of the above-mentioned factors was found to have an influence on the effectiveness of the intervention. The present study highlights the need for an early motor skill programme with a gender-specific approach in order to help low skilled boys and girls master a diverse set of motor skills

The maximally entangled symmetric state in terms of the geometric measure

The geometric measure of entanglement is investigated for permutation symmetric pure states of multipartite qubit systems, in particular the question of maximum entanglement. This is done with the help of the Majorana representation, which maps an n qubit symmetric state to n points on the unit sphere. It is shown how symmetries of the point distribution can be exploited to simplify the calculation of entanglement and also help find the maximally entangled symmetric state. Using a combination of analytical and numerical results, the most entangled symmetric states for up to 12 qubits are explored and discussed. The optimization problem on the sphere presented here is then compared with two classical optimization problems on the S^2 sphere, namely Toth's problem and Thomson's problem, and it is observed that, in general, they are different problems.Comment: 18 pages, 15 figures, small corrections and additions to contents and reference

Relationship of bacterial richness to organic degradation rate and sediment age in subseafloor sediment

© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Applied and Environmental Microbiology 82 (2016): 4994-4999, doi:10.1128/AEM.00809-16.Subseafloor sediment hosts a large, taxonomically rich and metabolically diverse microbial ecosystem. However, the factors that control microbial diversity in subseafloor sediment have rarely been explored. Here we show that bacterial richness varies with organic degradation rate and sediment age. At three open-ocean sites (in the Bering Sea and equatorial Pacific) and one continental margin site (Indian Ocean), richness decreases exponentially with increasing sediment depth. The rate of decrease in richness with depth varies from site to site. The vertical succession of predominant terminal electron acceptors correlates to abundance-weighted community composition, but does not drive the vertical decrease in richness. Vertical patterns of richness at the open-ocean sites closely match organic degradation rates; both properties are highest near the seafloor and decline together as sediment depth increases. This relationship suggests that (i) total catabolic activity and/or electron donor diversity exerts a primary influence on bacterial richness in marine sediment, and (ii) many bacterial taxa that are poorly adapted for subseafloor sedimentary conditions are degraded in the geologically young sediment where respiration rates are high. Richness consistently takes a few hundred thousand years to decline from near-seafloor values to much lower values in deep anoxic subseafloor sediment, regardless of sedimentation rate, predominant terminal electron acceptor, or oceanographic context.This work, including the efforts of Mitchell L. Sogin and Steven D’Hondt, was funded by Sloan Foundation (Census of Deep Life). This work, including the efforts of Steven D’Hondt, was funded by U.S. Science Support Program for IODP. This work, including the efforts of Steven D’Hondt, was funded by National Science Foundation (NSF) (OCE- 0752336 and OCE-0939564). The work of E. A. Walsh, J. B. Kirkpatrick, R. Pockalny, and J. Sauvage was funded by the grants to S. D’Hondt

Bacterial diversity and community composition from seasurface to subseafloor

© The International Society for Microbial Ecology, 2015. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in ISME Journal 10 (2016): 979–989, doi:10.1038/ismej.2015.175.We investigated compositional relationships between bacterial communities in the water column and those in deep-sea sediment at three environmentally distinct Pacific sites (two in the Equatorial Pacific and one in the North Pacific Gyre). Through pyrosequencing of the v4–v6 hypervariable regions of the 16S ribosomal RNA gene, we characterized 450 104 pyrotags representing 29 814 operational taxonomic units (OTUs, 97% similarity). Hierarchical clustering and non-metric multidimensional scaling partition the samples into four broad groups, regardless of geographic location: a photic-zone community, a subphotic community, a shallow sedimentary community and a subseafloor sedimentary community (greater than or equal to1.5 meters below seafloor). Abundance-weighted community compositions of water-column samples exhibit a similar trend with depth at all sites, with successive epipelagic, mesopelagic, bathypelagic and abyssopelagic communities. Taxonomic richness is generally highest in the water-column O2 minimum zone and lowest in the subseafloor sediment. OTUs represented by abundant tags in the subseafloor sediment are often present but represented by few tags in the water column, and represented by moderately abundant tags in the shallow sediment. In contrast, OTUs represented by abundant tags in the water are generally absent from the subseafloor sediment. These results are consistent with (i) dispersal of marine sedimentary bacteria via the ocean, and (ii) selection of the subseafloor sedimentary community from within the community present in shallow sediment.This study was funded by the Biological Oceanography Program of the US National Science Foundation (grant OCE-0752336) and by the NSF-funded Center for Dark Energy Biosphere Investigations (grant NSF-OCE-0939564)

The Expectation Monad in Quantum Foundations

The expectation monad is introduced abstractly via two composable adjunctions, but concretely captures measures. It turns out to sit in between known monads: on the one hand the distribution and ultrafilter monad, and on the other hand the continuation monad. This expectation monad is used in two probabilistic analogues of fundamental results of Manes and Gelfand for the ultrafilter monad: algebras of the expectation monad are convex compact Hausdorff spaces, and are dually equivalent to so-called Banach effect algebras. These structures capture states and effects in quantum foundations, and also the duality between them. Moreover, the approach leads to a new re-formulation of Gleason's theorem, expressing that effects on a Hilbert space are free effect modules on projections, obtained via tensoring with the unit interval.Comment: In Proceedings QPL 2011, arXiv:1210.029