Maxwell-Chern-Simons vortices in a CPT-odd Lorentz-violating Higgs Electrodynamics

We have studied BPS vortices in a CPT-odd and Lorentz-violating Maxwell-Chern-Simons-Higgs (MCSH) electrodynamics attained from the dimensional reduction of the Carroll-Field-Jackiw-Higgs model. The Lorentz-violating parameter induces a pronounced behavior at origin (for the magnetic/electric fields and energy density) which is absent in the MCSH vortices. For some combination of the Lorentz-violating coefficients there always exist a sufficiently large winding number $n_{0}$ such that for all $$ the magnetic field flips its signal, yielding two well defined regions with opposite magnetic flux. However, the total magnetic flux remains quantized and proportional to the winding number.Comment: Revtex style, 8 page

MODELLING OF HYDRODYNAMICS AROUND AN IMPERMEABLE BREAKWATER: COMPARISON BETWEEN PHYSICAL AND SPH NUMERICAL MODELING

This work presents the new developments and the validation of a Smoothed Particle Hydrodynamics (SPH) numerical model used in the National Laboratory of Civil Engineering (Laboratório Nacional de Engenharia Civil - LNEC) for studies in coastal engineering processes. Although the model requires a high CPU time, it proved to be very promising in the simulation of complex flows, such as the wave-structure interaction and the wave breaking phenomenon. For the SPH model validation, physical modeling tests were performed in one LNEC’s flume to study the interaction between an impermeable structure and an incident regular wave. The comparison between numerical and experimental results, i.e. free surface elevation, overtopping volume and pressure, shows the good accuracy of the SPH model to reproduce the various phenomena involving on the wave propagation and interaction with the structure, namely the wave breaking, the wave overtopping and the pressure field on the structure

X-ray method to study temperature-dependent stripe domains in MnAs/GaAs(001)

MnAs films grown on GaAs (001) exhibit a progressive transition between hexagonal (ferromagnetic) and orthorhombic (paramagnetic) phases at wide temperature range instead of abrupt transition during the first-order phase transition. The coexistence of two phases is favored by the anisotropic strain arising from the constraint on the MnAs films imposed by the substrate. This phase coexistence occurs in ordered arrangement alternating periodic terrace steps. We present here a method to study the surface morphology throughout this transition by means of specular and diffuse scattering of soft x-rays, tuning the photon energy at the Mn 2p resonance. The results show the long-range arrangement of the periodic stripe-like structure during the phase coexistence and its period remains constant, in agreement with previous results using other techniques.Comment: 4 pages, 4 figures, submitted to Applied Physics Letter

Extratos de vermicomposto na germinação e no crscimento inicial da alface romana.

No presente trabalho avaliou-se os efeitos de dois diferentes extratos de vermicomposto (TEA 50% e HUM 25%) e um tipo de lixiciado de vermicomposto (LV 25%) sobre a germinação e crescimento inicial de alface romana.Resumo expandido

Modified Gravity on the Brane and Dark Energy

We analyze the dynamics of an AdS5 braneworld with matter fields when gravity is allowed to deviate from the Einstein form on the brane. We consider exact 5-dimensional warped solutions which are associated with conformal bulk fields of weight -4 and describe on the brane the following three dynamics: those of inhomogeneous dust, of generalized dark radiation, and of homogeneous polytropic dark energy. We show that, with modified gravity on the brane, the existence of such dynamical geometries requires the presence of non-conformal matter fields confined to the brane.Comment: Revised version published in Gen. Rel. Grav. Typos corrected, updated reference and some remarks added for clarity. 11 pages, latex, no figure

Conformal Bulk Fields, Dark Energy and Brane Dynamics

In the Randall-Sundrum scenario we analyze the dynamics of a spherically symmetric 3-brane when the bulk is filled with matter fields. Considering a global conformal transformation whose factor is the $Z_2$ symmetric warp we find a new set of exact dynamical solutions for which gravity is bound to the brane. The set corresponds to a certain class of conformal bulk fields. We discuss the geometries which describe the dynamics on the brane of polytropic dark energy.Comment: 12 pages, latex, 2 figures. Talk given by Rui Neves at the Fourth International Conference on Physics Beyond the Standard Model, Beyond the Desert 03, Fundamental Experimental and Theoretical Developments in Particle Physics, Accelerator, Non-Accelerator and Space Approaches, Max Planck Institut f. Kernphysik/MPI Heidelberg, Castle Ringberg, Tegernsee, Germany, 9-14 June 2003. To be published in the Conference Proceedings, Springer-Verlag, Heidelberg, German

Análise exploratória de dados de monitoramento dos animais em um sistema de integração lavoura-pecuária.

Resumo: A aplicação dos preceitos da Agricultura de Precisão em um sistema de Integração Lavoura-Pecuária (ILP) envolve um grau de dificuldade maior devido ao número de fatores envolvidos e a presença da componente animal. Variáveis como a mobilidade, pisoteio, dejeções dos animais e zonas preferenciais podem impactar o sistema e devem ser consideradas. O objetivo deste trabalho é realizar uma análise exploratória dos dados de monitoramento de animais em um sistema ILP. Os dados foram obtidos por aparelhos GPS afixados em animais do rebanho e complementados por observações de campo. São apresentados mapas derivados da aplicação do estimador de intensidade Kernel para situações distintas e levantadas hipóteses sobre os comportamentos dos animais

Análise exploratória de dados de monitoramento dos animais em um sistema de integração lavoura-pecuária.

Resumo: A aplicação dos preceitos da Agricultura de Precisão em um sistema de Integração Lavoura-Pecuária (ILP) envolve um grau de dificuldade maior devido ao número de fatores envolvidos e a presença da componente animal. Variáveis como a mobilidade, pisoteio, dejeções dos animais e zonas preferenciais podem impactar o sistema e devem ser consideradas. O objetivo deste trabalho é realizar uma análise exploratória dos dados de monitoramento de animais em um sistema ILP. Os dados foram obtidos por aparelhos GPS afixados em animais do rebanho e complementados por observações de campo. São apresentados mapas derivados da aplicação do estimador de intensidade Kernel para situações distintas e levantadas hipóteses sobre os comportamentos dos animais