Top pair cross section measurements at the LHC

The most recent results on the measurements of (tt) production and cross sections at 7 TeV are presented. These are obtained using CMS [1] and ATLAS [2] data collected in 2011. Recent results on the tt production cross section at 8 TeV using 2012 CMS data are also presented. The tt inclusive cross sections are measured in the lepton+jets, dilepton and fully hadronic channels, including the tau-dilepton and tau+jets modes. The results are combined and confronted with precise theory calculations.Comment: Proceedings of CKM 2012, the 7th International Workshop on the CKM Unitarity Triangle, University of Cincinnati, USA, 28 September - 2 October 201

Effect of housing on rubber slat mats during pregnancy on the behaviour and welfare of sows in farrowing crates

peer-reviewedThe aim of this study was to evaluate the effect of flooring type during gestation, lameness and limb lesion scores on welfare and behaviour of sows in farrowing crates. Sixty sows group-housed during gestation in pens with solid concrete floored feeding stalls and a concrete, fully slatted group area either uncovered (CON; n = 30) or covered with 10 mm thick rubber slat mats (RUB; n = 30) were transferred to the farrowing crate at 110d of gestation (-5d). Lameness was scored on -5d and at weaning (28 d postfarrowing). Limb lesions were scored on -5d, 24 h later (-4d), 3 to 5 days post farrowing and at weaning (i.e., day 28 post farrowing). Sows were video recorded for 24 h on -5d, after the last piglet was born (FARROW) and prior to weaning. Videos were sampled every 10 min and an index of the proportion of time spent in different postures (standing [S], ventral [VL] and lateral lying [LL] and total lying) and number of postural changes was calculated. Median scores were calculated for limb lesions and classified as ≤ median or > median. Postural data were tested for normality and analysed using mixed model equations methodology. Flooring during gestation did not affect any of the variables recorded in this study. However, RUB sows tended to make more postural changes than CON sows (P = 0.10). Sows with swelling scores > median spent more time LL (68.9 vs. 63.1 ± 2.19%; P < 0.05) and less time VL (19.9 vs. 25.8 ± 2.27%; P < 0.05) than sows with swelling scores ≤ median. Time spent S and VL decreased and LL increased at FARROW compared to -5d and prior to weaning (P < 0.01). We found no effect of flooring type during gestation on welfare and behaviour in the farrowing crate. Factors such as limb lesions and adaptation to confinement (i.e., time spent inside the farrowing crate) appeared to have a greater influence on sow welfare and behaviour in farrowing crates than the flooring on which they were housed during gestation.This work was administered by Teagasc’s Walsh Fellowship Scheme via funding from Enterprise Ireland and EasyFix™ Rubber Products

Job Stability and Labor Mobility in Urban Mexico: A Study Based on Duration Models and Transition Analysis

Can the relatively slow growth of the formal sector in Mexico during the 1990s be attributed to a rigid labor market and to low turnover rates? Is the increasing share of workers in the informal sector and of self-employed workers evidence of market segmentation, and hence a source of inequality and poverty? Or, as suggested by Maloney (1997), could the relatively large and symmetric flows of workers among all sectors (formal, informal, self-employed, unemployed, etc. ) be more consistent with a well-integrated market where workers search across sectors for job opportunities than one where informal workers seek permanent status in the formal sector and stay until they retire?[1] [1] Maloney, (1997, p. 13).

Updating V_us from kaon semileptonic decays

We update the determination of |V_us| using semielectronic and semimuonic decays of K mesons. A modest improvement of 15% with respect to its present value is obtained for the error bar of this matrix element when we combine the four available semileptonic decays. The combined effects of long-distance radiative corrections and nonlinear terms in the vector form factors can decrease the value of |V_us| by up to 1%. Refined measurements of the decay widths and slope form factors in the semimuonic modes and a more accurate calculation of vector form factors at zero momentum transfer can push the determination of |V_us| at a few of percent level.Comment: 19 pages, 2 figure

Aplicación de la clase invertida en la educación superior: introducción a las nuevas tecnologías

Las autoras de este trabajo llevamos varios años trabajando con videos docentes para la enseñanza de las matemáticas dentro de la Economía a nivel universitario. Esto ha sido motivado por el auge de las nuevas tecnologías y las posibilidades docentes que nos proporcionan. La experiencia que teníamos en asignaturas virtuales nos ha permitido dar un paso más y utilizar los videos docentes en las clases presenciales. Si bien empezamos utilizándolos a modo de complemento, cuando conocimos la metodología de la flipped classroom (o clase invertida) nos planteamos una nueva forma de enseñanza. Decidimos invertir los papeles, de forma que el alumno, en vez de escuchar en clase y estudiar en casa, toma el papel protagonista, estudiando en casa con ayuda de videos y material proporcionado por el profesor y aprovecha el tiempo de clase para resolver ejercicios, plantear dudas y trabajar en equipo. Si bien esta metodología ha sido llevada a cabo con éxito en diversos niveles educativos, en el caso universitario no se conocen muchas experiencias. En nuestro caso hemos tenido que adaptarla, incorporando elementos adicionales, como el uso del programa Socrative para conseguir una mayor retroalimentación del aprendizaje del alumno. En el presente trabajo mostramos la experiencia que hemos llevado a cabo en el curso académico actual y recogemos la opinión de ambas partes, alumnos y profesores.Universidad de Málag