Evolução da vegetação de um campo natural (excluído e pastejado) e auto-ecologia de plantas indesejáveis.

A dinâmica da vegaetação campestre, assim como a auto-ecologia de cinco espécies indesejáveis (Eupatorium buniifolium - "chirca", Erianthus angustifolius - "macega", Baccharis coridifolia - "mio-mio", B. trimera - "carqueja", Eryngium horridum - caraguaté) foram estudadas durante 5 anos, visando obter informações sobre a evolução da vegetação e dados fenológicos das espécies indesejáveis.bitstream/item/110556/1/EVOLUCAO-DA-VEGETACAO.pd

Dynamical behavior of the Niedermayer algorithm applied to Potts models

In this work we make a numerical study of the dynamic universality class of the Niedermayer algorithm applied to the two-dimensional Potts model with 2, 3, and 4 states. This algorithm updates clusters of spins and has a free parameter, $E_0$, which controls the size of these clusters, such that $E_0=1$ is the Metropolis algorithm and $E_0=0$ regains the Wolff algorithm, for the Potts model. For $-1<E_0<0$, only clusters of equal spins can be formed: we show that the mean size of the clusters of (possibly) turned spins initially grows with the linear size of the lattice, $L$, but eventually saturates at a given lattice size $\widetilde{L}$, which depends on $E_0$. For $L \geq \widetilde{L}$, the Niedermayer algorithm is in the same dynamic universality class of the Metropolis one, i.e, they have the same dynamic exponent. For $E_0>0$, spins in different states may be added to the cluster but the dynamic behavior is less efficient than for the Wolff algorithm ($E_0=0$). Therefore, our results show that the Wolff algorithm is the best choice for Potts models, when compared to the Niedermayer's generalization.Comment: 10 pages, 11 figures, to be published in Physica A. arXiv admin note: substantial text overlap with arXiv:1003.365

Uso de atmosfera controlada dinâmica no armazenamento de maçã.

Resumo

Produtividade de Laranjeira Pêra sob porta-enxertos híbridos de Trifoliata.

No Brasil, o principal porta-enxerto utilizado para laranjeira Pera [Citrus sinensis (L.) Osbeck] é o limoeiro Cravo (C. limonia Osbeck). Todavia, este apresenta suscetibilidade ao declínio e à morte súbita dos citros (MSC), além de conferir aos frutos qualidade inferior à relacionada a outros porta-enxertos, como a tangerineira Sunki [C. sunki (Hayata) hort. ex Tanaka]

Produtividade de 13 variedades de Laranjeira Doce no Litoral Norte da Bahia..

O Brasil é o maior produtor mundial de laranja doce [Citrus sinensis (L.) Osbeck], respondendo por metade do suco de laranja produzido globalmente. Objetivou-se com esse estudo avaliar a produtividade de 13 variedades de laranjeira doce no Litoral Norte da Bahia

Elodie metallicity-biased search for transiting Hot Jupiters I. Two Hot Jupiters orbiting the slightly evolved stars HD118203 and HD149143

We report the discovery of a new planet candidate orbiting the subgiant star HD118203 with a period of P=6.1335 days. The best Keplerian solution yields an eccentricity e=0.31 and a minimum mass m2sin(i)=2.1MJup for the planet. This star has been observed with the ELODIE fiber-fed spectrograph as one of the targets in our planet-search programme biased toward high-metallicity stars, on-going since March 2004 at the Haute-Provence Observatory. An analysis of the spectroscopic line profiles using line bisectors revealed no correlation between the radial velocities and the line-bisector orientations, indicating that the periodic radial-velocity signal is best explained by the presence of a planet-mass companion. A linear trend is observed in the residuals around the orbital solution that could be explained by the presence of a second companion in a longer-period orbit. We also present here our orbital solution for another slightly evolved star in our metal-rich sample, HD149143, recently proposed to host a 4-d period Hot Jupiter by the N2K consortium. Our solution yields a period P=4.09 days, a marginally significant eccentricity e=0.08 and a planetary minimum mass of 1.36MJup. We checked that the shape of the spectral lines does not vary for this star as well.Comment: Accepted in A&A (6 pages, 6 figures