On Lorentz violation in e− ⁣ ⁣+ ⁣e+ ⁣→ ⁣μ− ⁣ ⁣+ ⁣μ+e^{-}\!\!+\!e^{+}\!\rightarrow\!\mu^{-}\!\!+\!\mu^{+} scattering at finite temperature

Small violation of Lorentz and CPT symmetries may emerge in models unifying gravity with other forces of nature. An extension of the standard model with all possible terms that violate Lorentz and CPT symmetries are included. Here a CPT-even non-minimal coupling term is added to the covariant derivative. This leads to a new interaction term that breaks the Lorentz symmetry. Our main objective is to calculate the cross section for the $e^{-}\!\!+\!e^{+}\!\rightarrow\!\mu^{-}\!\!+\!\mu^{+}$ scattering in order to investigate any violation of Lorentz and/or CPT symmetry at finite temperature. Thermo Field Dynamics formalism is used to consider finite temperature effects.Comment: 12 pages, 1 figure, accepted for publication in PL

Use of an enrichment analysis strategy to detect potential new drug targets in fungal genomes.

Fungi are a major class of pathogens in several animal and plant species, having a great agricultural, veterinary and medical importance. The search for anti-fungal drugs is an especially hard task due to the relative phylogenetic relatedness of fungi to their animal and vegetal hosts when compared with other classes of parasites, such as bacteria. This phylogenetic relatedness causes most of the potential druggable genes in fungi to be essential for both fungal and host genomes. This class of essential genes would tend to be observed at high frequencies in both groups. Essential genes specific of fungal species, however, would tend to be significantly more present in fungal genomes when compared with the frequency of the same gene in host genomes. In this study we used a software previously developed by our group named KOMODO (Kegg Orthology enrichMent analysis ? Online DetectiOn) that detects significantly under- or over-represented groups of homologous genes (as defined by KO groups) in one taxon when compared with the other. We used KOMODO to compare the Fungi and Eukarya taxa and identify significantly overrepresented KO groups in fungal genomes when compared with the eukaryotic background distribution of KO groups. Since each analysis using KOMODO tests thousands of hypotheses (one statistical test for each KO group surveyed), False Discovery Ratio approaches are implemented to control Type I error ratios and generate corrected q-values. Our software also displays the groups of biased homologous genes hierarchically classified according to their statistical significance and displayed into their proper biochemical roles as defined by Kegg Pathways into a dynamically generated webpage. The visual observation of the differentially represented genes adds an important source of information to help the biological comprehension of the phenomena behind the biased distributions detected. From the set of 2611 shared KO groups between Fungi and Eukarya taxa we found 88 of them to be significantly overrepresented in fungal genomes (q-value cutoff of <= 10e-5). These genes were then manually surveyed in scientific literature to verify if any of them was previously studied as essential and/or as a potential anti-fungal target. We found that some of these KO groups were already successfully evaluated as essential genes for fungal pathogenesis and/or survival, highlighting the ability of KOMODO to detect interesting gene candidates. More interestingly was the finding that most of the genes detected were never surveyed for their potential role in fungal survival. Additionally, several of these genes belong to essential pathways (such as sugar, amino acid and nucleotide metabolism), and could be considered as potential candidates for future studies to detect new essential genes for fungal survival. This study of case demonstrated the utility of KOMODO to detect both known and potentially new druggable genes by looking for enriched genes in fungal genomes when compared with other eukaryotes. As the number of complete genomes increase, we believe that a similar strategy could be used to survey other classes of eukaryotic parasites (such as protozoa, helminths and arthropods) for potential gene targets as well, making KOMODO a valuable tool to detect (and, consequently, prioritize) new drug targets in the figure of parasite-specific essential genes.X-MEETING 2011

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

Orbital magnetism in axially deformed sodium clusters: From scissors mode to dia-para magnetic anisotropy

Low-energy orbital magnetic dipole excitations, known as scissors mode (SM), are studied in alkali metal clusters. Subsequent dynamic and static effects are explored. The treatment is based on a self-consistent microscopic approach using the jellium approximation for the ionic background and the Kohn-Sham mean field for the electrons. The microscopic origin of SM and its main features (structure of the mode in light and medium clusters, separation into low- and high-energy plasmons, coupling high-energy M1 scissors and E2 quadrupole plasmons, contributions of shape isomers, etc) are discussed. The scissors M1 strength acquires large values with increasing cluster size. The mode is responsible for the van Vleck paramagnetism of spin-saturated clusters. Quantum shell effects induce a fragile interplay between Langevin diamagnetism and van Vleck paramagnetism and lead to a remarkable dia-para anisotropy in magnetic susceptibility of particular light clusters. Finally, several routes for observing the SM experimentally are discussed.Comment: 21 pages, 7 figure

Sistema de Balanço Hídrico: manual do desenvolvedor.

O Sistema Balanço Hídrico, elaborado pela Unidade, completa o Sistema AgroCast desenvolvido e divulgado pela Agência Estado. O AgroCast disponibiliza diversas informações para o AgroNegócio, como commodities, previsão de tempo, taxas etc. Já o sistema desenvolvido pela Unidade, disponibiliza na internet dados sobre o Balanço Hídrico para diversos estados de São Paulo, com a possibilidade de gerar dados especificamente para os tipos de solos existente na região.bitstream/item/116952/1/898.PD

Mathematical Methods applied in Image Enhancement using Matlab

In order to characterize complex engineering problems involvinging image data acquisition, different techniques in image processing can be used. One of those techniques is called the Laplacian Filter, commonly used to reduce noise and improving images. Based on that, image segmentation is a widely applied tool in engineering and it can greatly contribute in the acceleration of processes instead of adopting conventional methods, thus providing applications of such technique in the medical, spatial and other sectors linked to engineering. Therefore, this work aims to use image segmentation through differential equations (Laplacian Filter) in different images using Matlab mathematical software in order to enhance images details