Controle biológico no Brasil: situação, desafios e oportunidades.

bitstream/item/100005/1/2013AM05.pd

Topological Protection and Quantum Noiseless Subsystems

Encoding and manipulation of quantum information by means of topological degrees of freedom provides a promising way to achieve natural fault-tolerance that is built-in at the physical level. We show that this topological approach to quantum information processing is a particular instance of the notion of computation in a noiseless quantum subsystem. The latter then provide the most general conceptual framework for stabilizing quantum information and for preserving quantum coherence in topological and geometric systems.Comment: 4 Pages LaTeX. Published versio

Hamilton-Jacobi Theory and Information Geometry

Recently, a method to dynamically define a divergence function $D$ for a given statistical manifold $(\mathcal{M}\,,g\,,T)$ by means of the Hamilton-Jacobi theory associated with a suitable Lagrangian function $\mathfrak{L}$ on $T\mathcal{M}$ has been proposed. Here we will review this construction and lay the basis for an inverse problem where we assume the divergence function $D$ to be known and we look for a Lagrangian function $\mathfrak{L}$ for which $D$ is a complete solution of the associated Hamilton-Jacobi theory. To apply these ideas to quantum systems, we have to replace probability distributions with probability amplitudes.Comment: 8 page

Efeito da radiação UV-B sobre a capacidade antagônica de Clonostachys rosea a Botrytis cinerea em discos de folha de morango.

Resumo:: As atividades antrópicas estão alterando a concentração de gases na atmosfera, o ozônio da troposfera é um dos afetados e consequentemente a incidência de raios ultravioleta B (UV-B) na superfície da Terra tem sido alterada. A sensibilidade à radiação UV-B é uma das limitações do uso de agentes de biocontrole a campo. O objetivo deste trabalho foi avaliar o efeito da radiação UV-B em um isolado de Clonostachys rosea e quantificar a capacidade antagônica a Botrytis cinerea em discos de folhas de morango. Foram utilizadas quatro concentrações de conídios de C. rosea e quatro diferentes doses de radiação UV-B, sendo metade dos discos irradiados desafiados com conídios de B. cinerea. As concentrações de conídios de C. rosea acima de 105 conídios mL-1 apresentaram maior tolerância a radiação UV-B e apresentou nível de controle do patógeno superior a 75%, mesmo com a exposição à radiação. De acordo com os resultados, além de mostrar menor crescimento sob radiação UV-B, conídios de C. rosea apresentaram menor capacidade antagônica ao patógeno. Estudos adicionais são necessários para observar a tolerância de isolados de B. cinerea à radiação UV-B e assim, sugerir que um ambiente com radiação UV-B aumentada possa favorecer o patógeno

On the quantisation of the angular momentum

When a hydrogen-like atom is treated as a two dimensional system whose configuration space is multiply connected, then in order to obtain the same energy spectrum as in the Bohr model the angular momentum must be half-integral.Comment: Latex, 5 page

LBT/MODS spectroscopy of globular clusters in the irregular galaxy NGC 4449

We present intermediate-resolution (R$\sim$1000) spectra in the $\sim$3500-10,000 A range of 14 globular clusters in the magellanic irregular galaxy NGC 4449 acquired with the Multi Object Double Spectrograph on the Large Binocular Telescope. We derived Lick indices in the optical and the CaII-triplet index in the near-infrared in order to infer the clusters' stellar population properties. The inferred cluster ages are typically older than $\sim$9 Gyr, although ages are derived with large uncertainties. The clusters exhibit intermediate metallicities, in the range $-1.2\lesssim$[Fe/H]$\lesssim-0.7$, and typically sub-solar [$\alpha/Fe$] ratios, with a peak at $\sim-0.4$. These properties suggest that i) during the first few Gyrs NGC 4449 formed stars slowly and inefficiently, with galactic winds having possibly contributed to the expulsion of the $\alpha$-elements, and ii) globular clusters in NGC 4449 formed relatively "late", from a medium already enriched in the products of type Ia supernovae. The majority of clusters appear also under-abundant in CN compared to Milky Way halo globular clusters, perhaps because of the lack of a conspicuous N-enriched, second-generation of stars like that observed in Galactic globular clusters. Using the cluster velocities, we infer the dynamical mass of NGC 4449 inside 2.88 kpc to be M($<$2.88 kpc)=$3.15^{+3.16}_{-0.75} \times 10^9~M_\odot$. We also report the serendipitous discovery of a planetary nebula within one of the targeted clusters, a rather rare event.Comment: Accepted for publication in MNRAS; corrected typo in author lis

Gli aneurismi dell'aorta addominale. Diagnosi e trattamento [Aneurysms of the abdominal aorta. Diagnosis and treatment]

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