Non-minimal Maxwell-Chern-Simons theory and the composite Fermion model

The magnetic field redefinition in Jain's composite fermion model for the fractional quantum Hall effect is shown to be effectively described by a mean-field approximation of a model containing a Maxwell-Chern-Simons gauge field non-minimally coupled to matter. Also an explicit non-relativistic limit of the non-minimal (2+1)D Dirac equation is derived.Comment: 10 pages, no figure

Characterization of titanium welded joints by the orbital gas tungsten arc welding process for aerospace application

In this work, three welding programs for orbital gas tungsten arc welding (GTAW), previously developed, were used, using pulsed current and increasing speed (#A), constant current (#B) and pulsed current and decreasing current (#C). One of these should be used for the propulsion system of the Satellite CBERS (China – Brazil Earth Resources Satellite). Welded joints using tubes of commercially pure titanium were obtained with these procedures, which were characterized by means of mechanical and metallographic tests. The obtained results showed that the three welding procedures produce welded joints free of defects and with adequate shape. Although small differences on mechanical properties and on microstructure have been observed, the three welding programs attained compatible results with international standards used in the aerospace segment. The welding program #B, due to the reduced heat input used, was considered to obtain slightly advantage over the others

A genome survey of Moniliophthora perniciosa gives new insights into Witches' Broom Disease of cacao

<p>Abstract</p> <p>Background</p> <p>The basidiomycete fungus <it>Moniliophthora perniciosa </it>is the causal agent of Witches' Broom Disease (WBD) in cacao (<it>Theobroma cacao</it>). It is a hemibiotrophic pathogen that colonizes the apoplast of cacao's meristematic tissues as a biotrophic pathogen, switching to a saprotrophic lifestyle during later stages of infection. <it>M. perniciosa</it>, together with the related species <it>M. roreri</it>, are pathogens of aerial parts of the plant, an uncommon characteristic in the order Agaricales. A genome survey (1.9× coverage) of <it>M. perniciosa </it>was analyzed to evaluate the overall gene content of this phytopathogen.</p> <p>Results</p> <p>Genes encoding proteins involved in retrotransposition, reactive oxygen species (ROS) resistance, drug efflux transport and cell wall degradation were identified. The great number of genes encoding cytochrome P450 monooxygenases (1.15% of gene models) indicates that <it>M. perniciosa </it>has a great potential for detoxification, production of toxins and hormones; which may confer a high adaptive ability to the fungus. We have also discovered new genes encoding putative secreted polypeptides rich in cysteine, as well as genes related to methylotrophy and plant hormone biosynthesis (gibberellin and auxin). Analysis of gene families indicated that <it>M. perniciosa </it>have similar amounts of carboxylesterases and repertoires of plant cell wall degrading enzymes as other hemibiotrophic fungi. In addition, an approach for normalization of gene family data using incomplete genome data was developed and applied in <it>M. perniciosa </it>genome survey.</p> <p>Conclusion</p> <p>This genome survey gives an overview of the <it>M. perniciosa </it>genome, and reveals that a significant portion is involved in stress adaptation and plant necrosis, two necessary characteristics for a hemibiotrophic fungus to fulfill its infection cycle. Our analysis provides new evidence revealing potential adaptive traits that may play major roles in the mechanisms of pathogenicity in the <it>M. perniciosa</it>/cacao pathosystem.</p