Dynamics of a Self-interacting Scalar Field Trapped in the Braneworld for a Wide Variety of Self-interaction Potentials

We apply the dynamical systems tools to study the linear dynamics of a self-interacting scalar field trapped in the braneworld, for a wide variety of self-interaction potentials. We focus on Randall-Sundrum (RS) and on Dvali-Gabadadze-Porrati (DGP) braneworld models exclusively. These models are complementary to each other: while the RS brane produces ultra-violet (UV) corrections to general relativity, the DGP braneworld modifies Einstein's theory at large scales, i. e., produces infra-red (IR) modifications of general relativity. This study of the asymptotic properties of both braneworld models, shows -- in the phase space -- the way the dynamics of a scalar field trapped in the brane departs from standard general relativity behaviour.Comment: 12 pages, 5 figures and 5 table

Intraband Optical Absorption In Superlattices In An In-plane Magnetic Field

The absorption coefficient of GaAs-AlxGa1-xAs superlattices in an in-plane magnetic field is studied in the case of intraband transitions between electronic magnetic levels. A detailed analysis of the absorption peaks and their dependence on the magnetic-field intensity, superlattice period, and temperature, is performed. By taking into account the detailed properties of the magnetic subbands, the joint density of states, the transition matrix elements, and the effective sheet concentration of electrons involved in the optical transitions, a simple theoretical explanation is given for some experimental results previously reported. © 1993 The American Physical Society.4874516452

Relay synchronization in multiplex networks

Relay (or remote) synchronization between two not directly connected oscillators in a network is an important feature allowing distant coordination. In this work, we report a systematic study of this phenomenon in multiplex networks, where inter-layer synchronization occurs between distant layers mediated by a relay layer that acts as a transmitter. We show that this transmission can be extended to higher order relay configurations, provided symmetry conditions are preserved. By first order perturbative analysis, we identify the dynamical and topological dependencies of relay synchronization in a multiplex. We find that the relay synchronization threshold is considerably reduced in a multiplex configuration, and that such synchronous state is mostly supported by the lower degree nodes of the outer layers, while hubs can be de-multiplexed without affecting overall coherence. Finally, we experimentally validated the analytical and numerical findings by means of a multiplex of three layers of electronic circuits.the analytical and numerical findings by means of a multiplex of three layers of electronic circuits

Equilibrium tuned by a magnetic field in phase separated manganite

We present magnetic and transport measurements on La5/8-yPryCa3/8MnO3 with y = 0.3, a manganite compound exhibiting intrinsic multiphase coexistence of sub-micrometric ferromagnetic and antiferromagnetic charge ordered regions. Time relaxation effects between 60 and 120K, and the obtained magnetic and resistive viscosities, unveils the dynamic nature of the phase separated state. An experimental procedure based on the derivative of the time relaxation after the application and removal of a magnetic field enables the determination of the otherwise unreachable equilibrium state of the phase separated system. With this procedure the equilibrium phase fraction for zero field as a function of temperature is obtained. The presented results allow a correlation between the distance of the system to the equilibrium state and its relaxation behavior.Comment: 13 pages, 5 figures. Submited to Journal of Physics: Condensed Matte

INTRABAND OPTICAL-ABSORPTION IN SUPERLATTICES IN AN INPLANE MAGNETIC-FIELD

The absorption coefficient of GaAs-AlxGa1-xAs superlattices in an in-plane magnetic field is studied in the case of intraband transitions between electronic magnetic levels. A detailed analysis of the absorption peaks and their dependence on the magnetic-field intensity, superlattice period, and temperature, is performed. By taking into account the detailed properties of the magnetic subbands, the joint density of states, the transition matrix elements, and the effective sheet concentration of electrons involved in the optical transitions, a simple theoretical explanation is given for some experimental results previously reported.4874516452

ESTIMATED GENETIC INDEXES FOR BODY WEIGHT IN LAMAS

Se utilizó información de parición, destete y esquila de llamas Cha´ccus y K´aras, de los registros de la Estación Experimental del Centro de Investigaciones IVITA-Maranganí del periodo 1995-2001. Se estimó la heredabilidad (h2), repetibilidad y correlaciones genéticas de peso corporal al nacimiento, destete, y primera y segunda esquila ajustando los datos por efecto del año de producción, edad de la madre y sexo de la cría. Los valores de h2 se estimaron a través de un diseño de hermanos enteros, de medios hermanos paternos y regresión cría madre. La h2 para el peso al destete, tanto en llamas K´ara como en Cha´ccus fue alta, mientras que para el peso al nacimiento y peso vivo a la primera y segunda esquila tuvo valores de medio a alto. Los índices de repetibilidad para el peso vivo en llamas Cha´ccus y K´aras, estimados a través del método de la correlación intraclase fueron inferiores (0.3–0.4) que aquellos estimados a través del método de la regresión (0.6–0.7, respectivamente). Las correlaciones genéticas entre peso vivo al nacimiento con peso vivo al destete y primera esquila, y entre peso vivo al destete y peso vivo a la primera esquila presentaron valores altos y positivos en ambas variedades. Estos estimados son confiables para elegir el método de selección por índices en un plan de mejoramiento genético para la producción de carne.Parturition, weaning and shearing data of K´aras and Ch´accus lamas, collected from 1995 to 2001 at the IVITA Research Center, Maranganí of San Marcos University, was used in the present study to estimate the heritability (h2), repeatability and genetic correlations between body weight at birth, weaning and first and second shearing, by adjusting the fata for the effect of year, age of mother and sex of baby lama. The h2 value was analyzed by the nested effect using a model for brothers, brothers in law and by regression baby-mother. Heritability for body weight for both K´aras and Ch´accus lamas was high, while for birth weight and weight at first and second shearing varied from medium to high. The repeatability estimated by intraclass correlation for body weight of Ch´accus and K´aras was lower (0.3-0.4) than those estimated by regression (0.6-0.7, respectively). Genetic correlations between body weight at birth and at weaning and first shearing, and between body weight at weaning and at first shearing wee high and positive in both strains. These estimations are reliable to choose the appropriate selection index method for a genetic improvement program in lama meat production