Tempo quente e seco antecipa parte da safra de uva 2013 e o total produzido poderá superar 2012.

bitstream/item/74968/1/22-01-13-uva.pdf; bitstream/item/82448/1/MONTEIRO-Agrolink-jan2013.pdfCultivar, Pelotas, 22 jan. 2013. Publicado também no site da Agrolink em 17/01/13

NEAR-SURFACE EFFECTS IN MODELLING OSCILLATIONS OF ETA BOO

Following the report of solar-like oscillations in the G0 V star eta Boo (Kjeldsen et al. 1995, AJ 109, 1313), a first attempt to model the observed frequencies was made by Christensen-Dalsgaard et al. (1995, ApJ Letters, in press). This attempt succeeded in reproducing the observed frequency separations, although there remained a difference of about 10 microHz between observed and computed frequencies. In those models, the near-surface region of the star was treated rather crudely. Here we consider more sophisticated models that include non-local mixing-length theory, turbulent pressure and nonadiabatic oscillations.Comment: uuencoded and compressed Postscript (2 pages, including figure); To appear in Proceedings of IAU Colloquium 155, "Astrophysical Applications of Stellar Pulsation", Cape Town, South Afric

Molecules in external fields: a semiclassical analysis

We undertake a semiclassical analysis of the spectral properties (modulations of photoabsorption spectra, energy level statistics) of a simple Rydberg molecule in static fields within the framework of Closed-Orbit/Periodic-Orbit theories. We conclude that in addition to the usual classically allowed orbits one must consider classically forbidden diffractive paths. Further, the molecule brings in a new type of 'inelastic' diffractive trajectory, different from the usual 'elastic' diffractive orbits encountered in previous studies of atomic and analogous systems such as billiards with point-scatterers. The relative importance of inelastic versus elastic diffraction is quantified by merging the usual Closed Orbit theory framework with molecular quantum defect theory.Comment: 4 pages, 3 figure

Asteroseismic estimate of helium abundance of a solar analog binary system

16 Cyg A and B are among the brightest stars observed by Kepler. What makes these stars more interesting is that they are solar analogs. 16 Cyg A and B exhibit solar-like oscillations. In this work we use oscillation frequencies obtained using 2.5 years of Kepler data to determine the current helium abundance of these stars. For this we use the fact that the helium ionization zone leaves a signature on the oscillation frequencies and that this signature can be calibrated to determine the helium abundance of that layer. By calibrating the signature of the helium ionization zone against models of known helium abundance, the helium abundance in the envelope of 16 Cyg A is found to lie in the range 0.231 to 0.251 and that of 16 Cyg B lies in the range 0.218 to 0.266.Comment: Accepted for publication in Ap

Sensing directional forces in levitated optomechanics

Optomechanical devices are being harnessed as sensors of ultraweak forces for applications ranging from inertial sensing to the search for the elusive dark matter; For the latter, the focus is on detection of either higher energy single recoils or ultralight, narrowband sources; a directional signal is expected. However, the possibility of searching for a directional broadband signal need not be excluded; with this and other applications in mind, we apply a stochastic signal with a well defined direction, $\Psi$, to a trapped and cooled levitated nanosphere. We find that cross-correlation power spectra offer a calibration-free distinctive signature of the presence of a directional force, and its orientation quadrant, unlike normal power spectral densities (PSDs). With calibration we are able to accurately measure the angle $\Psi$, akin to a force compass in a plane

Condições meteorológicas e sua influência na vindima de 2011 no Rio Grande do Sul.

bitstream/item/48496/1/Comunicado-Tecnico-108.pd

Carência de macronutrientes e de boro em plantas de juta (Corchorus capsularis L.), variedade roxa.

bitstream/item/32693/1/CPATU-BP138.pd

3-D Photoionization Structure and Distances of Planetary Nebulae II. Menzel 1

We present the results of a spatio-kinematic study of the planetary nebula Menzel 1 using spectro-photometric mapping and a 3-D photoionization code. We create several 2-D emission line images from our long-slit spectra, and use these to derive the line fluxes for 15 lines, the Halpha/Hbeta extinction map, and the [SII] line ratio density map of the nebula. We use our photoionization code constrained by these data to derive the three-dimensional nebular structure and ionizing star parameters of Menzel 1 by simultaneously fitting the integrated line intensities, the density map, and the observed morphologies in several lines, as well as the velocity structure. Using theoretical evolutionary tracks of intermediate and low mass stars, we derive a mass for the central star of 0.63+-0.05 Msolar. We also derive a distance of 1050+_150 pc to Menzel 1.Comment: To be published in ApJ of 10th February 2005. 12 figure