A monopole solution from noncommutative multi-instantons

We extend the relation between instanton and monopole solutions of the selfduality equations in SU(2) gauge theory to noncommutative space-times. Using this approach and starting from a noncommutative multi-instanton solution we construct a U(2) monopole configuration which lives in 3 dimensional ordinary space. This configuration resembles the Wu-Yang monopole and satisfies the selfduality (Bogomol'nyi) equations for a U(2) Yang-Mills-Higgs system.Comment: 19 pages; title and abstract changed, brane interpretation corrected. Version to appear in JHE

Particle-vortex dynamics in noncommutative space

We study the problem of a charged particle in the presence of a uniform magnetic field plus a vortex in noncommutative planar space considering the two possible non-commutative extensions of the corresponding Hamiltonian, namely the ``fundamental'' and the ``antifundamental'' representations. Using a Fock space formalism we construct eigenfunctions and eigenvalues finding in each case half of the states existing in the ordinary space case. In the limit of $\theta \to 0$ we recover the two classes of states found in ordinary space, relevant for the study of anyon physics.Comment: 13 pages, no figures, plain LaTeX. References adde

Case studies on the geological application of LANDSAT imagery in Brazil

The author has identified the following significant results. Sao Domingos Range, Pocos de Caldas, and Araguaia and Tocantins Rivers in Brazil were selected as test sites for LANDSAT imagery. The satellite images were analyzed using conventional photointerpretation techniques, and the results indicate the application of small scale image data in regional structural data analysis, geological mapping, and mineral exploration

Regularized degenerate multi-solitons

We report complex PT-symmetric multi-soliton solutions to the Korteweg de-Vries equation that asymptotically contain one-soliton solutions, with each of them possessing the same amount of finite real energy. We demonstrate how these solutions originate from degenerate energy solutions of the Schrödinger equation. Technically this is achieved by the application of Darboux-Crum transformations involving Jordan states with suitable regularizing shifts. Alternatively they may be constructed from a limiting process within the context Hirota’s direct method or on a nonlinear superposition obtained from multiple Bäcklund transformations. The proposed procedure is completely generic and also applicable to other types of nonlinear integrable systems

Nonlinear Supersymmetry as a Hidden Symmetry

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High magnetic field thermal-expansion and elastic properties of CeRhIn5_5

We report high magnetic field thermal-expansion and magnetostriction results on CeRhIn$_5$ single crystals. Several transitions, both first and second order, are observed when the field is applied perpendicular to the crystallographic c-axis. The magnetic field dependence of the thermal-expansion coefficient above 15 K, where the magnetic correlations are negligible, can be explained supposing an almost pure $| \pm 5/2>$ ground state doublet, in apparent contradiction with neutron scattering experiments. Although the spin-lattice interaction is relevant in this compound, the effect of the magnetic correlations on the elastic properties is relatively weak, as revealed by resonant ultrasound spectroscopy experiments.Comment: 5 pages, 6 figure

Antioxidant and biochemical content in Brazilian guava germplasm with white, red and pink pulps.

Guava is considered to be an excellent source of antioxidant compounds due to the high content of lycopene and vitamin C. The international guava market is dominated mainly by white pulp fruit, differing from the Brazilian market, which pays a high price for guava cultivars with dark red pulp fruit. The goal of the present study was to analyze the content of Brazilian guava accessions contrasting for pulp colors to support the breeding program of guava, focusing on cultivars producing fruits with a high content of functional impounds. Sixty guava accessions established in a field germplasm bank, at Embrapa Tropical Semi-Arid, Petrolina, Pernambuco State, Brazil, were evaluated for total antioxidant activity, phenolic compounds, ascorbic acid, flavonoids, lycopene and beta-carotene, titrable acidity, soluble solids and total soluble sugars. The accessions, including guavas of white (n=10), red (n=23) and pink pulp (n=27), were grown in a block design experiment, with two replications/ accession. An ANOVA was performed, decomposing the degrees of freedom for the three pulp color groups in order to test the contrast to the nine evaluated compounds. The accessions presented high variability (p<0.01) for all compounds. Guava white pulp did not presented variability for the majority of compounds, except soluble solids, while guava red and pink pulps presented high variability (p <0.01) for most compounds, except flavonoids in pink pulp guava and flavonoids, beta-carotene, soluble solids and total sugars in red pulp fruit. The white*red and pink pulp contrast was significant (p<0.01) for most compounds, except for titrable acidity and soluble solids, with the greater mean values found in the accessions of pink red pulp, except for total soluble sugars. The red*pink contrast was also significant (p<0.01), except for titrable acidity and soluble solids, with greater values found in the accessions of red pulp fruit, except for lycopene and total soluble sugars. The compounds mean values were, approximately, 1.5, 1.4, 1.7, 1.8, 2.7 and 3.1 times greater for antioxidant activity, phenolic compounds, ascorbic acid, flavonoids, lycopene and beta-carotene, respectively, quantified in the pink and red pulp guava accessions when compared to white pulp. These results indicated that pink and red pulp guavas have a potential of greater beneficial contribution to the human diet than white pulp guava