Reservas de amido em sarmentos de videira 'Isabel precoce' submetida a diferentes épocas de poda e duas safras no ciclo.

Na região sul do Brasil, onde o clima é temperado, tradicionalmente colhe-se apenas uma safra/ciclo por ano. Alguns locais, como na Depressão Central do RS estão adotando manejo de dupla poda a fim de obter duas safras e oferecendo uma maior viabilidade financeira para o produtor que além de obter uma segunda safra, poderá ofertar em um período de baixa oferta de uva no mercado, recebendo mais pela produção. O objetivo deste trabalho foi avaliar as reservas de amido em sarmentos que se desenvolveram a partir de distintas datas de poda e em videiras com ou sem a prática de dupla colheita. O vinhedo de Isabel Precoce onde foi realizado o experimento está localizado no município de Eldorado do Sul-RS. A quantificação do amido foi por processo enzimático com posterior leitura em espectrofotômetro. Concluiu-se que a precocidade na poda de inverno auxilia no acúmulo de reservas de amido em sarmentos da videira por aumentar o ciclo vegetativo fotossinteticamente ativo das plantas e a dupla poda/colheita reduz os conteúdos de amido presentes no sarmento, principalmente no segundo período de crescimento, podendo debilitar a planta caso esta prática seja associada a podas tardias e realizada em anos sucessivos

Acceptance of fluorescence detectors and its implication in energy spectrum inference at the highest energies

Along the years HiRes and AGASA experiments have explored the fluorescence and the ground array experimental techniques to measure extensive air showers, being both essential to investigate the ultra-high energy cosmic rays. However, such Collaborations have published contradictory energy spectra for energies above the GZK cut-off. In this article, we investigate the acceptance of fluorescence telescopes to different primary particles at the highest energies. Using CORSIKA and CONEX shower simulations without and with the new pre-showering scheme, which allows photons to interact in the Earth magnetic field, we estimate the aperture of the HiRes-I telescope for gammas, iron nuclei and protons primaries as a function of the number of simulated events and primary energy. We also investigate the possibility that systematic differences in shower development for hadrons and gammas could mask or distort vital features of the cosmic ray energy spectrum at energies above the photo-pion production threshold. The impact of these effects on the true acceptance of a fluorescence detector is analyzed in the context of top-down production models

Diagnóstico de mastite subclínica caprina por meio da detecção de Staphylococcus aureus utilizando a técnica de RT-PCR.

A presente publicação descreve os procedimentos necessários para a identificação e confirmação molecular de estirpes de S. aureus causadoras de mastite subclínica, provenientes de amostras de leite de cabra, por meio da técnica de RT-PCR.bitstream/item/144724/1/CNPC-2015-Diagnostico-de-mastite.pd

Experimental analysis of lateral impact on planar brittle material: spatial properties of the cracks

The breakup of glass and alumina plates due to planar impacts on one of their lateral sides is studied. Particular attention is given to investigating the spatial location of the cracks within the plates. Analysis based on a phenomenological model suggests that bifurcations along the cracks' paths are more likely to take place closer to the impact region than far away from it, i. e., the bifurcation probability seems to lower as the perpendicular distance from the impacted lateral in- creases. It is also found that many observables are not sensitive to the plate material used in this work, as long as the fragment multiplicities corresponding to the fragmentation of the plates are similar. This gives support to the universal properties of the fragmentation process reported in for- mer experiments. However, even under the just mentioned circumstances, some spatial observables are capable of distinguishing the material of which the plates are made and, therefore, it suggests that this universality should be carefully investigated

Signature of the interaction between dark energy and dark matter in observations

We investigate the effect of an interaction between dark energy and dark matter upon the dynamics of galaxy clusters. This effect is computed through the Layser-Irvine equation, which describes how an astrophysical system reaches virial equilibrium and was modified to include the dark interactions. Using observational data from almost 100 purportedly relaxed galaxy clusters we put constraints on the strength of the couplings in the dark sector. We compare our results with those from other observations and find that a positive (in the sense of energy flow from dark energy to dark matter) non vanishing interaction is consistent with the data within several standard deviations.Comment: 13 pages, 3 figures; matches PRD published versio

Reentrant valence transition in EuO at high pressures: beyond the bond-valence model

The pressure-dependent relation between Eu valence and lattice structure in model compound EuO is studied with synchrotron-based x-ray spectroscopic and diffraction techniques. Contrary to expectation, a 7% volume collapse at $\approx$ 45 GPa is accompanied by a reentrant Eu valence transition into a \emph{lower} valence state. In addition to highlighting the need for probing both structure and electronic states directly when valence information is sought in mixed-valent systems, the results also show that widely used bond-valence methods fail to quantitatively describe the complex electronic valence behavior of EuO under pressure.Comment: 5 pages, 4 figure