The Flavour of Inflation

A new class of particle physics models of inflation based on the phase transition associated with the spontaneous breaking of family symmetry is proposed. The Higgs fields responsible for the breaking of family symmetry, the flavons, are natural inflaton candidates or waterfall fields in hybrid inflation. This opens up a rich vein of possible inflation models, all linked to the physics of flavour, with several interesting cosmological implications.Comment: Talk given at the 16th International Conference on Supersymmetry and the Unification of Fundamental Interactions (SUSY08), Seoul, Korea (June 16-21, 2008). To be published in the Conference Proceeding

S-Branes, Negative Tension Branes and Cosmology

A general class of solutions of string background equations is studied and its physical interpretations are presented. These solutions correspond to generalizations of the standard black p-brane solutions to surfaces with curvature k=-1,0. The relation with the recently introduced S-branes is provided. The mass, charge, entropy and Hawking temperature are computed, illustrating the interpretation in terms of negative tension branes. Their cosmological interpretation is discussed as well as their potential instability under small perturbations.Comment: 10 pages. Talks given at: SUSY'02, ``the 10th International Conference on Supersymmetry and Unification of Fundamental Interactions'', DESY, Hamburg, Germany, 17-23 June 2002, and ``The 1st International Conference on String Phenomenology'', Oxford, July 6 - 11, 2002. References adde

Modulated Reheating and Large Non-Gaussianity in String Cosmology

A generic feature of the known string inflationary models is that the same physics that makes the inflaton lighter than the Hubble scale during inflation often also makes other scalars this light. These scalars can acquire isocurvature fluctuations during inflation, and given that their VEVs determine the mass spectrum and the coupling constants of the effective low-energy field theory, these fluctuations give rise to couplings and masses that are modulated from one Hubble patch to another. These seem just what is required to obtain primordial adiabatic fluctuations through conversion into density perturbations through the `modulation mechanism', wherein reheating takes place with different efficiency in different regions of our Universe. Fluctuations generated in this way can generically produce non-gaussianity larger than obtained in single-field slow-roll inflation; potentially observable in the near future. We provide here the first explicit example of the modulation mechanism at work in string cosmology, within the framework of LARGE Volume Type-IIB string flux compactifications. The inflationary dynamics involves two light Kaehler moduli: a fibre divisor plays the role of the inflaton whose decay rate to visible sector degrees of freedom is modulated by the primordial fluctuations of a blow-up mode (which is made light by the use of poly-instanton corrections). We find the challenges of embedding the mechanism into a concrete UV completion constrains the properties of the non-gaussianity that is found, since for generic values of the underlying parameters, the model predicts a local bi-spectrum with fNL of order `a few'. However, a moderate tuning of the parameters gives also rise to explicit examples with fNL O(20) potentially observable by the Planck satellite.Comment: 42 pages, 2 figure

VLBI Polarimetry of 177 Sources from the Caltech-Jodrell Bank Flat-spectrum Survey

We present VLBA observations and a statistical analysis of 5 GHz VLBI polarimetry data from 177 sources in the Caltech-Jodrell Bank flat-spectrum (CJF) survey. The CJF survey, a complete, flux-density-limited sample of 293 extragalactic radio sources, gives us the unique opportunity to compare a broad range of source properties for quasars, galaxies and BL Lacertae objects. We focus primarily on jet properties, specifically the correlation between the jet axis angle and the polarization angle in the core and jet. A strong correlation is found for the electric vector polarization angle in the cores of quasars to be perpendicular to the jet axis. Contrary to previous claims, no correlation is found between the jet polarization angle and the jet axis in either quasars or BL Lac objects. With this large, homogeneous sample we are also able to investigate cosmological issues and AGN evolution.Comment: Accepted to the Astrophysical Journal: 37 pages, 14 figure

Collective narcissism moderates the effect of in-group image threat on intergroup hostility

WOS:000319485100005 (Nº de Acesso Web of Science)Results of 4 experiments demonstrated that under in-group image threat collective narcissism predicts retaliatory intergroup hostility. Under in-group criticism (vs. praise) collective narcissists expressed intention to harm the offending out-group but not other, nonoffending out-groups. This effect was specific to collective narcissism and was replicated in studies that accounted for the overlap between collective narcissism and individual narcissism, in-group positivity (in-group identification, blind and constructive patriotism), social dominance orientation, and right wing authoritarianism. The link between collective narcissism and retaliatory intergroup hostility under in-group image threat was found in the context of national identity and international relations and in the context of a social identity defined by university affiliation. Study 4 demonstrated that the relationship between collective narcissism and intergroup hostility was mediated by the perception of in-group criticism as personally threatening. The results advance our understanding of the mechanism driving the link between collective narcissism and intergroup hostility. They indicate that threatened egotism theory can be extended into the intergroup domain

Characterization of quality indices on storage of puree of mutant (dg and og^c) and normal tomatoes

The investigations carried out so far on high pigment tomatoes are confined to their nutritional aspects only. We present the comparative results of the first study on the kinetics of changes in chemical and sensory quality attributes in puree prepared from two colour mutants [dark green (dg) and old gold crimson (ogc)] and seven normal tomato genotypes during storage. Puree of mutant tomatoes BCT-115 and BCT-119, carrying dg and ogc genes, showed the less significant changes in TSS (7.52 and 6.02 °Brix), acidity (3.16 and 3.05%), pH (4.04 and 4.03), total sugar (12.4 and 11.13%), ascorbic acid (20.74 and 19.69 mg/100 g), lycopene (7.78 and 542 mg/100 g), and β-carotene (3.08 and 2.26 mg/100 g) during two months storage at 25 °C. Nevertheless, puree prepared from Berika and BCT-115 (dg) had higher colour (7.63 and 7.13), taste (7.4 and 7.37) and flavour (7.3 and 7.37) sensory scores during two months of storage at 25°C. These results provide new data on the effect of genotypes on the stability of quality for storage of tomato puree and insist on the utilization of these genotypes for breeding new processing cultivars in the near future

Seroprevalencia de Brucella canis en caninos del distrito de Pucusana

Estudia 202 sueros sanguíneos de perros residentes en el distrito de Pucusana mediante la técnica de Inmunodifusión en gel de agar y detectar seroprevalencia de anticuerpos contra Brucella canis en el distrito de Pucusana. Las muestras se tomaron entre los meses de enero, febrero y marzo del 2009 respectivamente, y fueron procesadas en el Laboratorio de Micología y Bacteriología Veterinaria de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos. Del total de muestras sometidos al estudio, 21.28 % (43/202) mostro ser positiva a la prueba de IDGA con un IC de 2.88%. De las variables que se consideraron en el presente estudio, sólo se encontró asociación estadística significativa en la correspondiente a sexo; esto se explica porque en el estudio la mayor cantidad de animales fueron machos en comparación de las hembras; en los machos 16.80% + 3.34% (21/125) y en las hembras es de 28.57% + 5.14% (22/77). De estos resultados se desprende que la prevalencia encontrada es más alta que la que se encontró en los Distritos de Bellavista y Callao en el 2005 (15.57% ± 3.33%) por lo que esta prevalencia representa un indicador de riesgo de la salud de la población expuesta.Tesi

Infrared glucose portable device

There are quite a few persons worldwide with severe issues to control the glucose level on its blood. Only in Mexico, there are about 10 million persons with this disease and well over 13 deaths in 100 in this country are due to diabetes. In order to help to control this health issue, we are proposing a device to measure in a swift, simple and efficient way abnormality glucose levels in blood by using infrared sensors. Glucose shows a high absorbance to infrared wavelength. By using such characteristic, it is possible to develop a mobile, low-cost electronic device capable to analyse a blood sample by measuring the absorbance in it. The process is performed by using an array of infrared diodes controlled by a low-power consumption microcontroller as well as by several algorithms within a case. A blood sample is put in a substrate within the case. Once analysed, the glucose level of such sample is analysed and displayed on a scree