Neutrino masses in SU(5)×U(1)FSU(5)\times U(1)_F with adjoint flavons

We present a $SU(5)\times U(1)_F$ supersymmetric model for neutrino masses and mixings that implements the seesaw mechanism by means of the heavy SU(2) singlets and triplets states contained in three adjoints of SU(5). We discuss how Abelian $U(1)_F$ symmetries can naturally yield non-hierarchical light neutrinos even when the heavy states are strongly hierarchical, and how it can also ensure that $R$--parity arises as an exact accidental symmetry. By assigning two flavons that break $U(1)_F$ to the adjoint representation of SU(5) and assuming universality for all the fundamental couplings, the coefficients of the effective Yukawa and Majorana mass operators become calculable in terms of group theoretical quantities. There is a single free parameter in the model, however, at leading order the structure of the light neutrinos mass matrix is determined in a parameter independent way.Comment: 16 pages, 9 figures. Included contributions to neutrino masses from the triplet states contained in the three adjoints of SU(5

Generalized Froggatt-Nielsen Mechanism

In this paper, we propose a Generalized Froggatt-Nielsen mechanism in which non-renormalizable operators involving a GUT group and $U(1)_H$ non-singlet Higgs field are introduced. Thus the GUT gauge symmetry breaking and the generation of hierarchical flavor hierarchy have a common origin in this mechanism. In this Generalized Froggatt-Nielsen mechanism, we propose universality conditions for coefficients corresponding to different contractions in the group productions. We find that the predictions in Generalized Froggatt-Nielsen mechanism for SU(5) GUT is different to that of ordinary Froggatt-Nielsen mechanism. Such Generalized Froggatt-Nielsen mechanism can be used in GUT models when ordinary Froggatt-Nielsen mechanism is no longer available. We study the application of Generalized Froggatt-Nielsen mechanism in SO(10) model. We find that realistic standard model mass hierarchy and mixings can be obtained both in SU(5) and SO(10) GUT models with such Generalized Froggatt-Nielsen mechanism.Comment: 4 pages, no figure

Bivariate genome-wide association meta-analysis of pediatric musculoskeletal traits reveals pleiotropic effects at the SREBF1/TOM1L2 locus

Bone mineral density is known to be a heritable, polygenic trait whereas genetic variants contributing to lean mass variation remain largely unknown. We estimated the shared SNP heritability and performed a bivariate GWAS meta-analysis of total-body lean mass (TB-LM) and total-body less head bone mineral density (TBLH-BMD) regions in 10,414 children. The estimated SNP heritability is 43% for TBLH-BMD, and 39% for TB-LM, with a shared genetic component of 43%. We identify variants with pleiotropic effects in eight loci, including seven established bone mineral density loci: _WNT4, GALNT3, MEPE, CPED1/WNT16, TNFSF11, RIN3, and PPP6R3/LRP5_. Variants in the _TOM1L2/SREBF1_ locus exert opposing effects TB-LM and TBLH-BMD, and have a stronger association with the former trait. We show that _SREBF1_ is expressed in murine and human osteoblasts, as well as in human muscle tissue. This is the first bivariate GWAS meta-analysis to demonstrate genetic factors with pleiotropic effects on bone mineral density and lean mass

Journal of Physics: Conference Series

1201

Maskana. Revista Científica

El balance hídrico asociado a la planificación de un proyecto de riego ubicado en una zona semiárida Chilena se modeló hidrológicamente utilizando el código WEAP21. Se aplicó un protocolo combinado de modelamiento determinístico/estocástico para definir los intervalos de predicción hidrológica del modelo. Se predijeron las implicaciones potenciales del cambio climático en la vida útil del proyecto de riego (año 2070) considerando la variabilidad de los pronósticos de precipitación y temperatura. Así, se consideró el escenario A1B del Informe del Panel Intergubernamental sobre cambio climático 2007, implementado por el Modelo Climático Regional (MCR) PRECIS-ECHAM, que fue desarrollado especialmente para condiciones Chilenas. El estudio reveló que la mayoría de los parámetros del modelo El balance hídrico asociado a la planificación de un proyecto de riego ubicado en una zona semiárida Chilena se modeló hidrológicamente utilizando el código WEAP21. Se aplicó un protocolo combinado de modelamiento determinístico/estocástico para definir los intervalos de predicción hidrológica del modelo. Se predijeron las implicaciones potenciales del cambio climático en la vida útil del proyecto de riego (año 2070) considerando la variabilidad de los pronósticos de precipitación y temperatura. Así, se consideró el escenario A1B del Informe del Panel Intergubernamental sobre cambio climático 2007, implementado por el Modelo Climático Regional (MCR) PRECIS-ECHAM, que fue desarrollado especialmente para condiciones Chilenas. El estudio reveló que la mayoría de los parámetros del modeloThe water balance of an irrigation project in the Chilean semi-arid zone was modelled using the WEAP21 code. A combined deterministic/stochastic protocol was applied for defining the hydrological prediction intervals of the model. Climate Change potential implications on the useful life of the irrigation project (year 2070) were predicted considering the variability in precipitation and temperature forecasts. Thereto, it was considered the scenario A1B of the 2007 Intergovernmental Panel on Climate Change report, generated by the Regional Climate Model PRECIS-ECHAM, specially developed for Chilean conditions. The study revealed that most of the inspected hydrological model parameters are insensitive to model predictions and the associated simulation limits may be categorized as acceptable. Nevertheless, the structure of WEAP21 had difficulties representing low flows because of the apparent inability to mimic the complex hydro-physical characteristics of the shrink-swell granitic soils which are predominant in the study basin. Even though the original Climate Change projections (CChP) of the RCM were refined, using observations of the historical period, it is important to underline that significant uncertainties may remain and as such the current results should be handled with care. With respect to historical records, mean annual climate forecasts suggest a maximum temperature increment of about +1.1oC and a maximum reduction in precipitation of 20.7%. The hydrological modelling suggests a maximum reduction in the mean annual streamflow of 49.7% and a reduction in the magnitude and frequency of streamflow peaks. Bearing in mind the potential uncertainties attached to CChP, the irrigation project will most probably be significantly affected in terms of water availability and crop water consumption since rainfall is expected to decrease and temperature, and as such evapotranspiration, to increase.Cuencavolumen 8, número

Recursos humanos y salud

Reunión: Conferencia Panamericana sobre Recursos Humanos y Atención Médica, 19-22 enero 1975, Medellín, C