Severity of banana leaf spot in an intercropping system in two cycles of banana Prata Ana

Prata Ana is the most planted banana cultivar in northern Minas Gerais, Brazil. It is however susceptible to several pathogens. This study was carried out to evaluate the disease severity of banana leaf spot in the Prata Ana cv. in the first and second cycle under six different planting systems. The randomized block experimental design was used with six treatments and four replications. lit an evaluation of the severity of banana leaf spot, no disease symptoms were found on Thap Maeo and Caipira. The evolution curve of the disease indicated seasonal effects in the first and second cycles. The severity, of banana leaf spot was highest soon after the regional rainy period from November to March. A comparison of the means of the evaluations indicated a reduction in disease severity from the first to the second cycle.

Spatial variability of soil physical properties in two management systems in sugarcane crop

O objetivo deste trabalho foi caracterizar a variabilidade espacial da densidade do solo (Ds), teor de água no solo (θ) e porosidade total (Pt) em dois sistemas de manejo da colheita da cana-de-açúcar, com queima e sem queima, em um Latossolo Vermelho, na camada de 0-0,20 m. A área de estudo está localizada no município de Rio Brilhante-MS, na Usina Eldorado. A parcela de cada talhão apresentou malha com comprimento de 180 m e largura de 145,6 m, perfazendo 90 pontos distribuídos na forma de uma grade de nove colunas por dez linhas, com pontos distanciados 20 m de seu vizinho. Foram coletadas amostras de solo na camada de 0-0,20 m, nos anos agrícolas de 2007/2008 e 2008/2009. O sistema de colheita com queima apresentou maior densidade em relação ao mecanizado, nos dois períodos de análise. O teor de água no solo, assim como a porosidade, teve aumento proporcional com relação à diminuição da densidade do sistema de colheita com queima para com o mecanizado.

Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Narrow row spacing and high plant population to short height castor genotypes in two cropping seasons

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ephemeroptera, Plecoptera and Trichoptera assemblages in two Atlantic Rainforest streams, Southeastern Brazil

Comunidades de Ephemeroptera, Plecoptera e Trichoptera (EPT) em substrato rochoso foram estudadas em dois riachos do Parque Estadual Intervales. Coletas com um amostrador de Surber (10 subamostras aleatórias, 1 m²) foram feitas mensalmente de setembro de 1999 a setembro de 2000 e trimestralmente de dezembro de 2000 a setembro de 2001 nos Ribeirões Bocaina e Água Comprida. A fauna de EPT do Ribeirão Bocaina foi mais diversificada e mais abundante do que a do Ribeirão Água Comprida. A fauna de EPT foi bastante diferente entre os dois riachos, tanto do ponto de vista da composição faunística quanto do ponto de vista funcional. Os resultados indicaram que não houve um padrão sazonal claro da variação temporal da densidade.

Chromosome polymorphism of heterochromatin and nucleolar regions in two populations of the fish Astyanax bockmanni (Teleostei: Characiformes)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Coherent properties and Rabi oscillations in two-level donor systems

Coherent properties and Rabi oscillations in two-level donor systems, under terahertz excitation, are theoretically investigated. Here we are concerned with donor states in bulk GaAs and GaAs-(Ga,Al)As quantum dots. We study confinement effects, in the presence of an applied magnetic field, on the electronic and on-center donor states in GaAs- (Ga,Al)As dots, as compared to the situation in bulk GaAs, and estimate some of the associated decay rate parameters. Using the optical Bloch equations with damping, we study the time evolution of the Is and 2p(+) states in the presence of an applied magnetic field and of a terahertz laser. We also discuss the role played by the distinct dephasing rates on the photocurrent and calculate the electric dipole transition moment. Results indicate that the Rabi oscillations are more robust as the total dephasing rate diminishes, corresponding to a favorable coherence time.

Modeling of interfaces in two-dimensional problems using solid finite elements with high aspect ratio

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Best practices for the implantation of ISO 14001 norms: a study of change management in two industrial companies in the Midwest region of the state of São Paulo - Brazil

Among the difficulties found in the implementation of ISO 14001 systems, resistance to change can always be found. It is mainly a consequence of the hurry to change, loss of focus, concentration of decision making at the level of top management, arbitrary imposition of objectives and results, faulty communication, and the absence of motivational and financial incentive for change.Therefore, the main objective of this paper is to present best practices with respect to the management of organizational change due to the implementation of ISO 14001 norms in two industrial companies in the Midwest region of the State of São Paulo - Brazil. (C) 2008 Elsevier Ltd. All rights reserved.

Structural aspects of the fermion-boson mapping in two-dimensional gauge and anomalous gauge theories with massive fermions

Using a synthesis of the functional integral and operator approaches we discuss the fermion-buson mapping and the role played by the Bose field algebra in the Hilbert space of two-dimensional gauge and anomalous gauge field theories with massive fermions. In QED, with quartic self-interaction among massive fermions, the use of an auxiliary vector field introduces a redundant Bose field algebra that should not be considered as an element of the intrinsic algebraic structure defining the model. In anomalous chiral QED, with massive fermions the effect of the chiral anomaly leads to the appearance in the mass operator of a spurious Bose field combination. This phase factor carries no fermion selection rule and the expected absence of Theta-vacuum in the anomalous model is displayed from the operator solution. Even in the anomalous model with massive Fermi fields, the introduction of the Wess-Zumino field replicates the theory, changing neither its algebraic content nor its physical content. (C) 2002 Elsevier B.V. (USA).

Scattering of neutral fermions by a pseudoscalar potential step in two-dimensional spacetime

The problem of scattering of neutral fermions in two-dimensional spacetime is approached with a pseudoscalar potential step in the Dirac equation. Some unexpected aspects of the solutions beyond the absence of Klein's paradox are presented. An apparent paradox concerning the uncertainty principle is solved by introducing the concept of effective Compton wavelength. Added plausibility for the existence of bound-state solutions in a pseudoscalar double-step potential found in a recent Letter is given. (C) 2003 Elsevier B.V. B.V. All rights reserved.

Confinement of spinless particles by Coulomb potentials in two-dimensional space-time

The problem of confinement of spinless particles in 1 + 1 dimensions is approached with a linear potential by considering a mixing of Lorentz vector and scalar couplings. Analytical bound-states solutions are obtained when the scalar coupling is of sufficient intensity compared to the vector coupling. (c) 2005 Elsevier B.V. All rights reserved.

Confinement of fermions by mixed vector-scalar linear potentials in two-dimensional space-time

The problem of confinement of fermions in 1 + 1 dimensions is approached with a linear potential in the Dirac equation by considering a mixing of Lorentz vector and scalar couplings. Analytical bound-states solutions are obtained when the scalar coupling is of sufficient intensity compared to the vector coupling. (C) 2002 Elsevier B.V. B.V. All rights reserved.