Hypercubic effects in semileptonic decays of heavy mesons, toward B→πℓνB \to \pi \ell \nu, with Nf=2+1+1N_f=2+1+1 Twisted fermions

We present a preliminary study toward a lattice determination of the vector and scalar form factors of the $B \to \pi \ell \nu$ semileptonic decays. We compute the form factors relative to the transition between heavy-light pseudoscalar mesons, with masses above the physical D-mass, and the pion. We simulate heavy-quark masses in the range $m_c^{phys} < m_h < 2m_c^{phys}$. Lorentz symmetry breaking due to hypercubic effects is clearly observed in the data, and included in the decomposition of the current matrix elements in terms of additional form factors. We discuss the size of this breaking as the parent-meson mass increases. Our analysis is based on the gauge configurations produced by the European Twisted Mass Collaboration with $N_f = 2 + 1 + 1$ flavors of dynamical quarks at three different values of the lattice spacing and with pion masses as small as $210$ MeV.Comment: 7 pages, 5 figures; contribution to the XXXVI International Symposium on Lattice Field Theory (LATTICE2018), East Lansing (Michigan State University, USA), July 22-28, 201

Effects of different simplified milk recording methods on genetic evaluation with test-day animal model

The aims of the present study were to compare estimated breeding values (EBV) for milk yield using different testing schemes with a test-day animal model and to evaluate the effect of different testing schemes on the ranking of top sheep. Alternative recording schemes that use less information than that currently obtained with a monthly test-day schedule were employed to estimate breeding values. A random regression animal mixed model that used a spline function of days in milk was fitted. EBVs obtained with alternative recording schemes showed different degrees of Spearman correlation with EBVs obtained using the monthly recording scheme. These correlations ranged from 0.77 to 0.92. A reduction in accuracy and intensity of selection could be anticipated if these alternative schemes are used; more research in this area is needed to reduce the costs of test-day recording

K→πK \to \pi semileptonic form factors with Nf=2+1+1N_f=2+1+1 Twisted Mass fermions

We present a lattice QCD determination of the vector and scalar form factors of the semileptonic $K \to \pi \ell \nu$ decay which are relevant for the extraction of the CKM matrix element $|V_{us}|$ from experimental data. Our results are based on the gauge configurations produced by the European Twisted Mass Collaboration with $N_f = 2+1+1$ dynamical fermions, which include in the sea, besides two light mass degenerate quarks, also the strange and the charm quarks. We use data simulated at three different values of the lattice spacing and with pion masses as small as $210$ MeV. Our final result for the vector form factor at zero momentum transfer is $f_+(0) = 0.9709 (46)$, where the uncertainty is both statistical and systematic combined in quadrature. Using the latest experimental value of $f_+(0) |V_{us}|$ from $K_{\ell 3}$ decays, we obtain $|V_{us}| = 0.2230 (11)$, which allows to test the unitarity constraint of the Standard Model below the permille level once the determination of $|V_{ud}|$ from superallowed nuclear $\beta$ decays is adopted. A slight tension with unitarity at the level of $\sim 2$ standard deviations is observed. Moreover we present our results for the semileptonic scalar $f_0(q^2)$ and vector $f_+(q^2)$ form factors in the whole range of values of the squared four-momentum transfer $q^2$ measured in $K_{\ell 3}$ decays, obtaining a very good agreement with the momentum dependence of the experimental data. We provide a set of synthetic data points representing our results for the vector and scalar form factors at the physical point for several selected values of $q^2$.Comment: 37 pages, 5 tables, 9 figures; version to appear in PR

The burden of minimal hepatic encephalopathy: from diagnosis to therapeutic strategies

Minimal hepatic encephalopathy (MHE) is the mildest form of hepatic encephalopathy (HE). It affects the performance of psychometric tests focused on attention, working memory, psychomotor speed, and visuospatial ability, as well as electrophysiological and other functional brain measures. MHE is a frequent complication of liver disease, affecting up to 80% of tested patients. By being related to falls, an impairment in fitness to drive and the development of overt HE, MHE severely affects the lives of patients and caregivers by altering their quality of life and their socioeconomic status. MHE is detected in clinically asymptomatic patients using appropriate psychometric tests and neurophysiological methods that highlight neuropsychological alterations, such as video-spatial orientation deficits, attention disorders, memory, reaction times, electroencephalogram slowing, prolongation of latency-evoked cognitive potentials, and reduction in the critical flicker frequency. Several treatments have been proposed for MHE treatment, including non-absorbable disaccharides, poorly absorbable antibiotics such as rifaximin, probiotics and branched-chain amino acids. However, because of the multiple diagnosis methods, the various endpoints of treatment trials and the variety of agents used in trials, the treatment of MHE is not currently recommended as routine, but only on a case-by-case basis

Estimation of genetic and phenotypic parameters for bacteriological status of the udder,somatic cell score,and milk yield in dairy sheep using a threshold animal model

The objective of this study was to estimate the genetic parameters for infection status (INF), as indicator of mastitis, SCS (i.e., log-transformed SCC), and milk yield (MY), by using a Gibbs sampling algorithm. The data comprised 17,843 test-day records of 2,040 ewes. The pedigree file included 2,948 animals. A bivariate variance component analysis was performed using the TM software. Fixed effects considered in the analysis were litter size, parity, flock by test-day interaction, year by season of lambing interaction, and stage of lactation; whereas the animal, and the permanent environmental effect within and across lactations were considered as random as well as the error. Flat priors were used for both fixed effects and variance components. Parameters were drawn from the posterior conditional distributions. The posterior means of heritability for MY, SCS and INF were equal to 0.14, 0.09, and 0.09, respectively; whereas the repeatability within lactation was around 0.30 for the three traits, and ranged between 0.29 and 0.41 across lactations. The genetic correlation between INF and SCS was equal to 0.93, suggesting that selection for low SCS would also lead to a reduced incidence of mastitis. On the other hand, the positive and moderate genetic correlation between mastitis and milk yield (0.59) confirms the antagonistic association between udder health and milk yield. Therefore, in breeding programs that emphasize milk yield, the unfavorable genetic correlation between milk yield and mastitis, may result in an increased incidence of the latter