Analytical BPS Maxwell-Higgs vortices

We have established a prescription for the calculation of analytical vortex solutions in the context of generalized Maxwell-Higgs models whose overall dynamics is controlled by two positive functions of the scalar field. We have also determined a natural constraint between these functions and the Higgs potential allowing the existence of axially symmetric Bogomol'nyi-Prasad-Sommerfield (BPS) solutions possessing finite energy. Furthermore, when the generalizing functions are chosen suitably, the nonstandard BPS equations can be solved exactly. We have studied some examples, comparing them with the usual Abrikosov-Nielsen-Olesen (ANO) solution. The overall conclusion is that the analytical self-dual vortices are well-behaved in all relevant sectors, strongly supporting the generalized models they belong themselves. In particular, our results mimic well-known properties of the usual (numerical) configurations, as localized energy density, while contributing to the understanding of topological solitons and their description by means of analytical methods.Comment: 8 pages, 4 figure

Effects of a CPT-even and Lorentz-violating nonminimal coupling on the electron-positron scattering

We propose a new \emph{CPT}-even and Lorentz-violating nonminimal coupling between fermions and Abelian gauge fields involving the CPT-even tensor $(K_{F})_{\mu\nu\alpha\beta}$ of the standard model extension. We thus investigate its effects on the cross section of the electron-positron scattering by analyzing the process $e^{+}+e^{-}\rightarrow\mu^{+}+\mu^{-}$. Such a study was performed for the parity-odd and parity-even nonbirefringent components of the Lorentz-violating $(K_{F})_{\mu\nu\alpha\beta}$ tensor. Finally, by using experimental data available in the literature, we have imposed upper bounds as tight as $10^{-12}(eV)^{-1}$ on the magnitude of the CPT-even and Lorentz-violating parameters while nonminimally coupled.Comment: LaTeX2e, 06 pages, 01 figure

Radiative generation of the CPT-even gauge term of the SME from a dimension-five nonminimal coupling term

In this letter we show for the first time that the usual CPT-even gauge term of the standard model extension (SME) can be radiatively generated, in a gauge invariant level, in the context of a modified QED endowed with a dimension-five nonminimal coupling term recently proposed in the literature. As a consequence, the existing upper bounds on the coefficients of the tensor $(K_{F})$ can be used improve the bounds on the magnitude of the nonminimal coupling, $\lambda(K_{F}),$ by the factors $10^{5}$ or $10^{25}.$ The nonminimal coupling also generates higher-order derivative contributions to the gauge field effective action quadratic terms.Comment: Revtex style, two columns, 6 pages, revised final version to be published in the Physics Letters B (2013

Micropropagação de café conilon.

Este folder explica o processo de micropropagação. Está divido nos seguintes tópicos: Cultura de Tecidos Vegetais na Embrapa Rondônia; Micropropagação de café Conilon: Descrição, Pontos fortes, Oportunidade.bitstream/item/46911/1/folder-micropropagacao.pd

Desinfestação de explantes radiculares de bacurizeiro.

Este trabalho teve como objetivo avaliar a desinfestação de explantes radiculares de bacurizeiro para o seu estabelecimento in vitro

Determination of callus growth curve in conilon coffee.

A cultura de calos tem mostrado grande potencial para multiplicação em larga escala de genótipos superiores e em curto espaço de tempo. O objetivo deste trabalho foi induzir a formação de calos em explantes foliares de Coffea canephora var. Conilon, e avaliar o desenvolvimento dos calos, determinando sua curva crescimento. A curva de crescimento de calos permite inferir sobre o momento adequado para subcultivá-los em novo meio de cultura. Os explantes foram inoculados em meio MS 50% com 10 mg.L-1 de tiamina, 1 mg.L-1 de piridoxina, 1 mg.L-1 de ácido nicotínico, 1 mg.L-1 de glicina, 100 mg.L-1 de inositol, 100 mg.L-1 de caseína hidrolisada e 400 mg.L-1 de extrato de malte, 20 g.L-1 de sacarose, 8 g.L-1 de ágar e acrescido de AIB (10 HM), 2,4-D (20 HM) e 2iP (10 HM). Para determinar a curva de crescimento, calos foram pesados até o 60º dia de cultivo. A curva de crescimento dos calos seguiu um padrão sigmóide, com cinco fases distintas. O subcultivo deve ser feito no 53º dia, visando à regeneração de plantas

Genotype rotation for management of resistance to the sorghum anthracnose pathogen Colletotrichum sublineolum.

Sulemento. Edição do IX International Congress of Plant Pathology, 2008, Torino. Abstracts on invited and offered papers