Trapping of Spin-0 fields on tube-like topological defects

We have considered the localization of resonant bosonic states described by a scalar field $\Phi$ trapped in tube-like topological defects. The tubes are formed by radial symmetric defects in $(2,1)$ dimensions, constructed with two scalar fields $\phi$ and $\chi$, and embedded in the $(3,1)-$dimensional Minkowski spacetime. The general coupling between the topological defect and the scalar field $\Phi$ is given by the potential $\eta F(\phi,\chi)\Phi^2$. After a convenient decomposition of the field $\Phi$, we find that the amplitudes of the radial modes satisfy Schr\"odinger-like equations whose eigenvalues are the masses of the bosonic resonances. Specifically, we have analyzed two simple couplings: the first one is $F(\phi,\chi)=\chi^2$ for a fourth-order potential and, the second one is a sixth-order interaction characterized by $F(\phi,\chi)=(\phi\chi)^2$% . In both cases the Schr\"odinger-like equations are numerically solved with appropriated boundary conditions. Several resonance peaks for both models are obtained and the numerical analysis showed that the fourth-order potential generates more resonances than the sixth-order one.Comment: 7 pages, 10 figures, matches version published in Physics Letters

The role performed by the teacher’s question in the learning of quadratic function in an exploratory mathem

Communication plays a key role in teaching and learning processes. Questions are a communicational act greatly used by teachers to structure their discourse, establish dynamics, and foster interaction between the different participants in the classroom. In view of these potentialities of questions in the classroom context, we have developed a teaching experiment with the aim of understand the role of the teacher's question in the learning of topics on functions. Considering the nature of this aim, a methodology of qualitative and interpretative nature was used. The data collection was based on the students’ written productions and on the audio and video recordings of a mathematics class of a Grade 10 educational group (in northern Portugal). Data analysis is based on content analysis techniques, crossing collected data and categories emerging from the literature. The study revealed that the teacher’s questions alternated between confirmation, focalization, and inquiry, with inquiry prevailing. Questions aimed at testing the student’s knowledge gave both the teacher and actual student important information. Questions that focused the student’s attention on a particular detail enabled the students to organize their reasoning and structure their answer. Questions that required the students to explain or justify their thoughts were those that proved to most contribute to the development of the student’s reasoning process.info:eu-repo/semantics/publishedVersio

Analysis of equilibrium in industrial variables through Error Correction Models

This research aimed to evaluate the relationship between variables of the temperature adjustment and the percentage of heating in the molding oven of the Polyethylene Terephthalate Resin (PTR) used in the manufacture of the preform of two-liter bottles. It also investigated the direction of causality between these variables in order to determine how an external shock is transmitted to the system. Vector Error Correction (VEC) methodology was used to carry out this study. It was possible to identify the variable to be monitored and estimate the minimum time for the system to reach the stability of the oven temperature

Introdução, coleta e caracterização de recursos genéticos de guandu para produção e grãos e forragem.

O guandu (Cajanus cajan (L.) Millspaugh) é uma das principais leguminosas cultivadas nos trópicos e subtrópicos. Apesar de ocupar o sexto lugar no mundo em área e produção de grãos em relação a outras leguminosas, como o feijão, ervilha e grão-de-bico, presenta, em relação a essas, maior diversidade de uso

Preliminary evaluation of pigeonpea genotypes in the Brazilian Semi-Arid Tropics.

Pigeonpea is a potential crop for the Brazilian semiárid region. However, the available information about it is very limited. Embrapa - Cpatsa, has been carrying out a breeding program to identify suitable genotypes for grain and forage production, using introductions from other regions of the country and from abroad, especially from ICRISAT Asia Center, India