Parâmetros de qualidade de frutos de novos híbridos de abacaxizeiros desenvolvidos pela Embrapa Mandioca e Fruticultura.

O fruto do abacaxizeiro é bastante apreciado e apresenta grande aceitação no mercado mundial em decorrência de suas características sensoriais e nutricionais. O programa de melhoramento genético do abacaxizeiro da Embrapa Mandioca e Fruticultura desenvolve novos híbridos para atender às expectativas deste mercado

Fluctuations and oscillations in a simple epidemic model

We show that the simplest stochastic epidemiological models with spatial correlations exhibit two types of oscillatory behaviour in the endemic phase. In a large parameter range, the oscillations are due to resonant amplification of stochastic fluctuations, a general mechanism first reported for predator-prey dynamics. In a narrow range of parameters that includes many infectious diseases which confer long lasting immunity the oscillations persist for infinite populations. This effect is apparent in simulations of the stochastic process in systems of variable size, and can be understood from the phase diagram of the deterministic pair approximation equations. The two mechanisms combined play a central role in explaining the ubiquity of oscillatory behaviour in real data and in simulation results of epidemic and other related models.Comment: acknowledgments added; a typo in the discussion that follows Eq. (3) is corrected

Calculations of three-body observables in ^8B breakup

We discuss calculations of three-body observables for the breakup of ^8B on a ^{58}Ni target at low energy using the coupled discretised continuum channels approach. Calculations of both the angular distribution of the ^7Be fragments and their energy distributions are compared with those measured at several laboratory angles. In these observables there is interference between the breakup amplitudes from different spin-parity excitations of the projectile. The resulting angle and the energy distributions reveal the importance of the higher-order continuum state couplings for an understanding of the measurements.Comment: 22 pages (postscript), accepted in Phys. Rev.

Qualitative Approach to Semi-Classical Loop Quantum Cosmology

Recently the mechanism was found which allows avoidance of the cosmological singularity within the semi-classical formulation of Loop Quantum Gravity. Numerical studies show that the presence of self-interaction potential of the scalar field allows generation of initial conditions for successful slow-roll inflation. In this paper qualitative analysis of dynamical system, corresponding to cosmological equations of Loop Quantum Gravity is performed. The conclusion on singularity avoidance in positively curved cosmological models is confirmed. Two cases are considered, the massless (with flat potential) and massive scalar field. Explanation of initial conditions generation for inflation in models with massive scalar field is given. The bounce is discussed in models with zero spatial curvature and negative potentials.Comment: Online at http://www.iop.org/EJ/abstract/1475-7516/2004/07/01

Deformed Gaussian Orthogonal Ensemble Analysis of the Interacting Boson Model

A Deformed Gaussian Orthogonal Ensemble (DGOE) which interpolates between the Gaussian Orthogonal Ensemble and a Poissonian Ensemble is constructed. This new ensemble is then applied to the analysis of the chaotic properties of the low lying collective states of nuclei described by the Interacting Boson Model (IBM). This model undergoes a transition order-chaos-order from the $SU(3)$ limit to the $O(6)$ limit. Our analysis shows that the quantum fluctuations of the IBM Hamiltonian, both of the spectrum and the eigenvectors, follow the expected behaviour predicted by the DGOE when one goes from one limit to the other.Comment: 10 pages, 4 figures (avaiable upon request), IFUSP/P-1086 Replaced version: in the previous version the name of one of the authors was omitte

Monitoramento da bicheira-da-raiz em áreas de arroz com utilização de sementes tratadas e não tratadas com inseticida.

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Improvements in reading and spelling skills after a phonological and morphological knowledge intervention in Greek children with spelling difficulties : a pilot study

In this study, we evaluated the effects of the online computer-based training program “Lexilogy-Greek” on the reading and spelling performance of young poor readers and spellers. The training is based on psycholinguistic principles that emphasize the importance of acquiring efficient phonological as well as morphological knowledge in remediating reading and spelling difficulties. Our sample consisted of fifteen 5th and 6th grade primary school children. Reading and spelling were tested at three points, with a no-intervention period and subsequently an intervention period in between these time points. We adopted a single group repeated measurement design and tested for intervention effects using repeated measures ANOVAs. The results revealed substantial treatment effects on spelling, word reading fluency and text reading fluency

Monitoramento do herbicida penoxsulam e dos fungicidas carboxina e tiram em água, Sedimento e solo de lavoura de arroz irrigado por inundação.

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