New Physics effects in the flavor-changing neutral couplings of the Top quark

We survey the flavor-changing neutral couplings (FCNC) of the top quark predicted by some extensions of the Standard Model: THDM, SUSY, L-R symmetric, TC2, 331, and models with extra quarks. Since the expected sensitivity of the LHC and ILC for the tcV (V=\gamma,g,Z) and tcH couplings is of order of a few percent, we emphasize the importance of any new physics effect that gives a prediction for these FCNC couplings within this limit. We also review the constraints imposed on these couplings from low-energy precision measurements.Comment: 19 pages, 7 figures. Accepted as a review paper in Int. J. of Mod. Phys.

Obtención de jarabes glucosados por hidrólisis enzimática empleando almidón de sorgo CIAPR-132

La presente investigación está encaminada al estudio de la posible sustitución del maíz por el sorgo en la producción de jarabes glucosados para la industria alimenticia, considerando la evaluación de las potencialidades de dicho cereal. En este sentido se realizó un diseño experimental compuesto del tipo 2k, utilizando  el Software Statgraphics Centurion XV en elprocesamiento de los resultados del proceso desarrolladoen el laboratorio. Para ello se analizó la influenciade las variables independientes: concentración deenzima alfa amilasa (X1) en los niveles de 0,06 y 0,16%p/p, la concentración de enzima amiloglucosidasa(AMG) (X2) en los niveles de 0,18 y 0,375 %p/p ytiempo de sacarificación (X3) de 24 y 48 horas sobrelas variables respuestas °Brix y Azúcares ReductoresTotales (ART); además se determinó el rendimiento de cada experimento, obteniéndose los mejores resultados para la mayor concentración de enzima alfaamilasa, concentración de enzima AMG y tiempo de sacarificación en los menores valores. Los mejores resultados se obtuvieron para el Brix de 52,22 y ARTde 68,76%

Herramienta software para el cálculo de la radiación solar en superficies con distinta inclinación: ORIENTSOL

Este documento pretende presentar una herramienta software de carácter didáctico que hace más sencillo tanto la enseñanza como el aprendizaje del cálculo de la radiación solar sobre superficies inclinadas. Este concepto forma parte de los contenidos de la asignatura optativa, “Instalaciones fotovoltaicas”. Ésta es ofertada por la Universidad de Jaén en el plan de estudios correspondiente a Ingeniero Técnico Industrial en las especialidades de: Mecánica, Electricidad y Electrónica Industrial

Lepton Number Violation from Colored States at the LHC

The possibility to search for lepton number violating signals at the Large Hadron Collider (LHC) in the colored seesaw scenario is investigated. In this context the fields that generate neutrino masses at the one-loop level are scalar and Majorana fermionic color-octets of SU(3). Due to the QCD strong interaction these states may be produced at the LHC with a favorable rate. We study the production mechanisms and decays relevant to search for lepton number violation signals in the channels with same-sign dileptons. In the simplest case when the two fermionic color-octets are degenerate in mass, one could use their decays to distinguish between the neutrino spectra. We find that for fermionic octets with mass up to about 1 TeV the number of same-sign dilepton events is larger than the standard model background indicating a promising signal for new physics.Comment: minor corrections, added reference

Urinary Excretion of Mimosine Derivatives by Cows with and without Experience in Consumption of \u3cem\u3eLeucaena leucocephala\u3c/em\u3e

Leucaena leucocephala is a leguminous tree widely distributed in the tropical regions of the world. In Mexico, it has been incorporated into silvopastoral systems and is highly regarded, owing to its high content of crude protein. Nonetheless, L. leucocephala contains secondary metab-olites, such as mimosine, a non-protein free amino acid, which may induce toxic effects in unadapted ruminants that consume the forage (Hammond 1995). Although Synergistes jonesii, an anaerobic bacterium, has the ability to degrade 3,4-DHP and 2,3-DHP to non-toxic compounds (Allison et al. 1992), in Mexico its presence has not yet been confirmed. Recent work has suggested the occurrence of sub-clinical toxicity to 3,4-DHP and 2,3-DHP in cattle grazing L. leucocephala in Australia and Thailand (Graham 2007; Dalzell et al. 2012; Phaikaew et al. 2012). Several options such as the transfer of rumen liquor and the adaptation of ruminants to the intake of L. leucocephala have been studied in an attempt to reduce the excretion of mimosine and its metabolites (Palmer et al. 2010). The aim of the present work was to evaluate the effect of the experience of consumption of L. leucocephala on excretion of mimosine derivatives (3,4-DHP and 2,3-DHP) in the urine of cattle

The mitochondrial activity of leukocytes from Artibeus jamaicensis bats remains unaltered after several weeks of flying restriction

Bats are the only flying mammals known. They have longer lifespan than other mammals of similar size and weight and can resist high loads of many pathogens, mostly viruses, with no signs of disease. These distinctive characteristics have been attributed to their metabolic rate that is thought to be the result of their flying lifestyle. Compared with non-flying mammals, bats have lower production of reactive oxygen species (ROS), and high levels of antioxidant enzymes such as superoxide dismutase. This anti-oxidative vs. oxidative profile may help to explain bat's longer than expected lifespans. The aim of this study was to assess the effect that a significant reduction in flying has on bats leukocytes mitochondrial activity. This was assessed using samples of lymphoid and myeloid cells from peripheral blood from Artibeus jamaicensis bats shortly after capture and up to six weeks after flying deprivation. Mitochondrial membrane potential (Δψm), mitochondrial calcium (mCa2+), and mitochondrial ROS (mROS) were used as key indicators of mitochondrial activity, while total ROS and glucose uptake were used as additional indicators of cell metabolism. Results showed that total ROS and glucose uptake were statistically significantly lower at six weeks of flying deprivation (p 0.05). These results suggest that bat mitochondria are stable to sudden changes in physical activity, at least up to six weeks of flying deprivation. However, decrease in total ROS and glucose uptake in myeloid cells after six weeks of captivity suggest a compensatory mechanism due to the lack of the highly metabolic demands associated with flying

Chromomagnetic Dipole Moment of the Top Quark Revisited

We study the complete one-loop contributions to the chromagnetic dipole moment $\Delta\kappa$ of the top quark in the Standard Model, two Higgs doublet models, topcolor assited technicolor models (TC2), 331 models and extended models with a single extra dimension. We find that the SM predicts $\Delta\kappa = - 0.056$ and that the predictions of the other models are also consitent with the constraints imposed on $\Delta\kappa$ by low-energy precision measurements.Comment: 20 pages, 5 figures, Updat