On the Integrability and Chaos of an N=2 Maxwell-Chern-Simons-Higgs Mechanical Model

We apply different integrability analysis procedures to a reduced (spatially homogeneous) mechanical system derived from an off-shell non-minimally coupled N=2 Maxwell-Chern-Simons-Higgs model that presents BPS topological vortex excitations, numerically obtained with an ansatz adopted in a special - critical coupling - parametric regime. As a counterpart of the regularity associated to the static soliton-like solution, we investigate the possibility of chaotic dynamics in the evolution of the spatially homogeneous reduced system, descendant from the full N=2 model under consideration. The originally rich content of symmetries and interactions, N=2 susy and non-minimal coupling, singles out the proposed model as an interesting framework for the investigation of the role played by (super-)symmetries and parametric domains in the triggering/control of chaotic behavior in gauge systems. After writing down effective Lagrangian and Hamiltonian functions, and establishing the corresponding canonical Hamilton equations, we apply global integrability Noether point symmetries and Painleveproperty criteria to both the general and the critical coupling regimes. As a non-integrable character is detected by the pair of analytical criteria applied, we perform suitable numerical simulations, as we seek for chaotic patterns in the system evolution. Finally, we present some Comments on the results and perspectives for further investigations and forthcoming communications.Comment: 18 pages, 5 figure

Optical-force laws for guided light in linear media

CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORThe mechanical response of transparent materials to optical forces is a topic that concerns a wide range of fields, from the manipulation of biological material by optical tweezers to the design of nano-optomechanical systems. However, the fundamental aspects of such forces have always been surrounded by controversies, and several different formulations have been proposed. In this paper, we propose a general stress tensor formalism to put all optical forces in a consistent presentation that allows us to study how different predictions emerge, and use the specific case of light propagating as a superposition of guided modes in lossless dielectric waveguides as a physical example. We use this formalism to calculate optical forces for straight and curved waveguide sections and all possible excitation configurations for a given set of coupled eigenmodes, and then compare the results for each of the known proposed optical-force laws in a framework that permits distinguishing where there will be differences between the force laws proposed. The general formalism also allows us to show that proper use of the divergence theorem is crucial to account for all force terms, many of which vanish if the procedure most commonly used is applied for situations other than eigenmodes in straight waveguides in vacuum. Finally, it is known that discrepancies in the predicted forces arise from the incompleteness of each stress tensor with respect to the total-energy-momentum tensor of the system. A better understanding of how different stress tensors predict very different forces for certain waveguide geometries should open a pathway to identifying how to properly assemble the full tensor, as well as for experimental tests to confirm the predictions.100117CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMIG - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAISCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORSem informaçãoSem informaçãoSem informaçã

Produção de palha e forragem por espécies anuais e perenes em sucessão à soja.

O objetivo deste trabalho foi avaliar a produção de palha e de forragem por forrageiras anuais e perenes implantadas em sucessão à cultura da soja, e seus efeitos sobre a produtividade de grãos da cultura no próximo cultivo. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas (crescimento livre e sob cortes sucessivos), com quatro repetições. Foram avaliadas oito forrageiras em dois municípios de Mato Grosso do Sul. A produção de palha e forragem foi avaliada em 2005 e 2006, nas espécies Urochloa ruziziensis; U. decumbens; U. brizantha cv. Marandu e Xaraés; Panicum maximum cv. Tanzânia e Mombaça, P. maximum x P. infestans cv. Massai; Pennisetum americanum cv. BRS 1501; e Sorghum bicolor cv. Santa Elisa. As forrageiras foram semeadas mecanicamente após a colheita da soja, em 1/4/2005 e 24/3/2006, em São Gabriel do Oeste, e em 20/3/2005 e 13/3/2006, em Dourados. Sorgo, U. brizantha cv. Xaraés e P. maximum cv. Tanzânia apresentaram características como elevada produtividade, alta qualidade da forragem e facilidade de controle, favoráveis para produção tanto de forragem quanto de palha. Urochloa ruziziensis e U. decumbens apresentaram melhor desempenho para a produção de palha. O cultivo das espécies forrageiras em sucessão à soja não afeta a produtividade da cultura.The objective of this work was to evaluate forage and straw production, of annual and perennial forage implanted in succession to soybean, and their effects on crop grain yield in the following season. The experimental design was in randomized blocks with four replicates, in a split-plot arrangement (free growth and successive cuts). Eight forages were evaluated in two municipalities of the state of Mato Grosso do Sul, Brazil. Straw and forage production was evaluated in 2005 and 2006, in the following species: Urochloa ruziziensis, U. decumbens; U. brizantha cv. Marandu and Xaraés; Panicum maximum cv. Tanzânia and Mombaça, P. maximum x P. infestans cv. Massai, Pennisetum americanum cv. BRS 1501, and Sorghum bicolor cv. Santa Elisa. Forages were planted mechanically, after the soybean crop harvest on 4/1/2005 and 3/24/2006, in São Gabriel do Oeste, and 3/20/2005 and 3/13/2006, in Dourados. Sorghum, U. brizantha cv. Xaraés and P. maximum cv. Tanzânia characteristics, such as high productivity, high forage quality and easiness in control, were favorable for production of both forage and straw. Urochloa ruziziensis and U. decumbens showed better performance for straw production. Forage cultivation in soybean succession does not affect crop yield

Forage peanut variability: genetic parameters for agronomic and nutritive traits in time-separate trials.

Successful breeding programs depend on the information defined through the evaluation of parameters obtained according to the selection strategy, based on the correlated responses among the multiple traits evaluated and the environmental influence. As follows, the objective of this study was to estimate the genetic parameters for agronomic and nutritive traits of forage peanut to subsidize the selection of more adapted genotypes. We evaluated 67 genotypes in three separate trials with two common controls. Agronomic and nutritive data were analyzed using the mixed model methodology (REML/BLUP) for each trial. Genetic parameters were estimated for all the variables and genotypic values served as a basis for checking the genetic correlation among traits. There was genetic variability and environmental influence for the traits analyzed, except for nutritive ones. Individual heritabilities, in general, were low to moderate and the traits of forage production (vigor, height, ground cover, and total and leaves dry matter yields) correlated with each other in the three trials. There is a favorable condition for the selection of agronomic traits, with high accuracy and consistency among trials. There is the possibility of indirect selection with the use of agronomic traits related to forage yield

Experimental Observation of Quantum Correlations in Modular Variables

We experimentally detect entanglement in modular position and momentum variables of photon pairs which have passed through $D$-slit apertures. We first employ an entanglement criteria recently proposed in [Phys. Rev. Lett. {\bf 106}, 210501 (2011)], using variances of the modular variables. We then propose an entanglement witness for modular variables based on the Shannon entropy, and test it experimentally. Finally, we derive criteria for Einstein-Podolsky-Rosen-Steering correlations using variances and entropy functions. In both cases, the entropic criteria are more successful at identifying quantum correlations in our data.Comment: 7 pages, 4 figures, comments welcom

Efeito de antioxidantes na conservação do coco verde descascado.

O objetivo do presente estudo foi estudar o efeito de agentes sulfitantes e ácidos orgânicos na conservação e manutenção da aparência do coco verde descascado, envolvido em filme de polietileno de baixa densidade e mantido sob refrigeração

Equilíbrio nutricional e distúrbios fisiológicos em manga Tommy Atkins.

Com o objetivo de avaliar o efeito do equilíbrio nutricional sobre a incidência de distúrbios fisiológicos em manga 'Tommy Atkins' cultivada no Vale do São Francisco, realizou-se um ensaio com frutos coletados no estádio de maturação fisiológica, classificados em frutos sem sintomas e com sintomas de distúrbio fisiológico. Os frutos das duas classes foram separados em casca, polpa e caroço, e levados para secagem em estufa a 65oC. Este material foi submetido a mineralização para a determinação das concentrações de N, K, Ca, Mg e B. Antes da desidratação, uma parte da polpa foi separada para as determinações do teor de sólidos solúveis totais (SST) e da acidez total titulável (ATT). Os resultados permitem concluir que, tanto as concentrações elevadas de Ca e Mg, como as baixas relações N/Ca e K/Ca, tanto na polpa quanto na casca, foram eficientes na prevenção de distúrbios fisiológicos nos frutos de mangueira; a concentração de nutrientes obtida na casca pode refletir melhor a condição da fisiopatia do que a concentração dos nutrientes na polpa dos frutos; os valores de SST e a relação SST/ATT determinada nos frutos com sintomas foram muito mais elevados do que nos frutos sem sintomas, devido a uma sobrematuração desordenada dos tecidos da polpa

Banco de germoplasma de amendoim forrageiro: conservação e utilização.

A alternativa mais promissora para relacionar os recursos genéticos vegetais e os programas de melhoramento, e assim, aumentar a utilização dos acessos do Banco Ativo de Germoplasma (BAG), é a intensificação das atividades de pré-melhoramento. O presente trabalho teve como objetivo realizar um levantamento dos estudos de caracterização e avaliação realizados no BAG de Amendoim Forrageiro, com ênfase em suas relações com o programa de melhoramento genético

Heritability and variability of bromatological traits evaluated in Panicum maximum hybrids in the Western Amazon.

The knowledge of the genetic parameters of bromatological traits in forages is essential to support the selection of genotypes that will be released as new cultivars. The objectives of this study were to estimate the heritability coefficients and verify the existence of genetic variability of bromatological traits in Panicum maximum hybrids, evaluated in the Western Amazon in different harvests over the year