Synchronization in a ring of pulsating oscillators with bidirectional couplings

We study the dynamical behavior of an ensemble of oscillators interacting through short range bidirectional pulses. The geometry is 1D with periodic boundary conditions. Our interest is twofold. To explore the conditions required to reach fully synchronization and to invewstigate the time needed to get such state. We present both theoretical and numerical results.Comment: Revtex, 4 pages, 2 figures. To appear in Int. J. Bifurc. and Chao

An intrinsic Proper Generalized Decomposition for parametric symmetric elliptic problems

We introduce in this paper a technique for the reduced order approximation of parametric symmetric elliptic partial differential equations. For any given dimension, we prove the existence of an optimal subspace of at most that dimension which realizes the best approximation in mean of the error with respect to the parameter in the quadratic norm associated to the elliptic operator, between the exact solution and the Galerkin solution calculated on the subspace. This is analogous to the best approximation property of the Proper Orthogonal Decomposition (POD) subspaces, excepting that in our case the norm is parameter-depending, and then the POD optimal sub-spaces cannot be characterized by means of a spectral problem. We apply a deflation technique to build a series of approximating solutions on finite-dimensional optimal subspaces, directly in the on-line step. We prove that the partial sums converge to the continuous solutions, in mean quadratic elliptic norm.Comment: 18 page

Neutrino Masses in Split Supersymmetry

We investigate the possibility to generate neutrino masses in the context of Split supersymmetric scenarios where all sfermions are very heavy. All relevant contributions coming from the R-parity violating terms to the neutrino mass matrix up to one-loop level are computed, showing the importance of the Higgs one-loop corrections. We conclude that it is not possible to generate all neutrino masses and mixings in Split SUSY with bilinear R-Parity violating interactions. In the case of Partial Split SUSY the one-loop Higgs contributions are enough to generate the neutrino masses and mixings in agreement with the experiment. In the context of minimal SUSY SU(5) we find new contributions which help us to generate neutrino masses in the case of Split SUSY.Comment: 33 pages, 6 figures, to appear in Physical Review

The contribution of secondary eclipses as astrophysical false positives to exoplanet transit surveys

We investigate in this paper the astrophysical false-positive configuration in exoplanet-transit surveys that involves eclipsing binaries and giant planets which present only a secondary eclipse, as seen from the Earth. To test how an eclipsing binary configuration can mimic a planetary transit, we generate synthetic light curve of three examples of secondary-only eclipsing binary systems that we fit with a circular planetary model. Then, to evaluate its occurrence we model a population of binaries in double and triple system based on binary statistics and occurrence. We find that 0.061% +/- 0.017% of main-sequence binary stars are secondary-only eclipsing binaries mimicking a planetary transit candidate down to the size of the Earth. We then evaluate the occurrence that an occulting-only giant planet can mimic an Earth-like planet or even smaller planet. We find that 0.009% +/- 0.002% of stars harbor a giant planet that present only the secondary transit. Occulting-only giant planets mimic planets smaller than the Earth that are in the scope of space missions like Kepler and PLATO. We estimate that up to 43.1 +/- 5.6 Kepler Objects of Interest can be mimicked by this new configuration of false positives, re-evaluating the global false-positive rate of the Kepler mission from 9.4% +/- 0.9% to 11.3% +/- 1.1%. We note however that this new false-positive scenario occurs at relatively long orbital period compared with the median period of Kepler candidates.Comment: 9 pages, 4 figures, accepted for publication in A&

Anti-de Sitter wormhole kink

The metric describing a given finite sector of a four-dimensional asymptotically anti-de Sitter wormhole can be transformed into the metric of the time constant sections of a Tangherlini black hole in a five-dimensional anti-de Sitter spacetime when one allows light cones to tip over on the hypersurfaces according to the conservation laws of an one-kink. The resulting kinked metric can be maximally extended, giving then rise to an instantonic structure on the euclidean continuation of both the Tangherlini time and the radial coordinate. In the semiclassical regime, this kink is related to the existence of closed timelike curves.Comment: 10 pages, to appear in IJMP

System dynamics modelling in systems biology and applications in pharmacology

El modelado matemático de sistemas biológicos complejos es uno de los temas clave en la Biología de Sistemas y varios métodos computacionales basados ​​en la simulación computarizada han sido aplicados hasta ahora para determinar el comportamiento de los sistemas no lineales. La Dinamica de Sistemas es una metodología de modelado intuitivo basada en el razonamiento cualitativo por el cual un modelo conceptual se puede describir como un conjunto de relaciones de causa y efecto entre las variables de un sistema. A partir de esta estructura, es posible obtener un conjunto de ecuaciones dinámicas que describan cuantitativamente el comportamiento del sistema. Centrándose en los sistemas farmacológicos, el modelado compartimental a menudo se utiliza para resolver un amplio espectro de problemas relacionados con la distribución de materiales en los sistemas vivos en la investigación, el diagnóstico y la terapia en todo el cuerpo, los órganos y los niveles celulares. En este artículo presentamos la metodología de modelado de Dinámica del Sistema y su aplicación al modelado de un modelo compartimental farmacocinético-farmacodinámico del efecto de profundidad anestésica en pacientes sometidos a intervenciones quirúrgicas, derivando un modelo de simulación en el entorno de simulación orientada a objetos OpenModelica. La Dinamica de Sistemas se puede ver como una herramienta educativa poderosa y fácil de usar y en la enseñanza de Biología de Sistemas.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech