Vacuum Polarization by a Magnetic Flux Tube at Finite Temperature in the Cosmic String Spacetime

In this paper we analyse the effect produced by the temperature in the vacuum polarization associated with charged massless scalar field in the presence of magnetic flux tube in the cosmic string spacetime. Three different configurations of magnetic fields are taken into account: $(i)$ a homogeneous field inside the tube, $(ii)$ a field proportional to $1/r$ and $(iii)$ a cylindrical shell with $\delta$-function. In these three cases, the axis of the infinitely long tube of radius $R$ coincides with the cosmic string. Because the complexity of this analysis in the region inside the tube, we consider the thermal effect in the region outside. In order to develop this analysis, we construct the thermal Green function associated with this system for the three above mentioned situations considering points in the region outside the tube. We explicitly calculate in the high-temperature limit, the thermal average of the field square and the energy-momentum tensor.Comment: 16 pages, 1 figur

Determinação do nivel de resistência de campo de acessos de alface e avaliação da resistência de acessos de alface (Lactuca sativa) ao groundnut ringspot virus (GRSV) em condições de casa de vegetação.

Com o objetivo de avaliar a resistência de campo de genótipos de alface do Banco de Germoplasma da Embrapa montou-se um ensaio com 30 genótipos em três repetições de 12 plantas por parcela.Resumo 9

Esterilização de suco de abacaxi por microfiltração

bitstream/item/75839/1/ct39-2000.pd

Impacto Alimentar Esofágico, um Dilema Diagnóstico

O impacto alimentar esofágico é uma situação que na maioria dos casos é secundária a patologia esofágica congénita ou adquirida, podendo constituir a primeira manifestação da doença. Descreve-se um rapaz, 11 anos, saudável, com sialorreia e dor retrosternal que surgiram subitamente durante o jantar. Foi submetido a endoscopia digestiva alta, que revelou um fragmento de carne impactado no terço distal do esófago (que foi extraído) e estrias longitudinais na mucosa. A análise histológica das biópsias esofágicas foi compatível com eosinofilia esofágica. Iniciou terapêutica com inibidor da bomba de protões com melhoria clínica e histológica. O diagnóstico diferencial das principais causas de impacto alimentar associadas a eosinofilia esofágica, nomeadamente esofagite eosinofílica, doença do refluxo gastroesofágico e eosinofilia esofágica respondedora a inibidor da bomba de protões, constitui um desafio clínico.info:eu-repo/semantics/publishedVersio

Mutations Of Androgen Receptor Gene In Brazilian Patients With Male Pseudohermaphroditism.

We describe the identification of point mutations in the androgen receptor gene in five Brazilian patients with female assignment and behavior. The eight exons of the gene were amplified by the polymerase chain reaction (PCR) and analyzed for single-strand conformation polymorphism (SSCP) to detect the mutations. Direct sequencing of the mutant PCR products demonstrated single transitions in three of these cases: G-->A in case 1, within exon C, changing codon 615 from Arg to His; G-->A in case 2, within exon E, changing codon 752 from Arg to Gln, and C-->T in case 3, within exon B, but without amino acid change.31775-

Leaching studies for metals recovery from printed circuit boards scrap

In this paper, the leaching behavior of the major metals present in printed circuit boards waste is evaluated, aiming at its recycling by hydrometallurgy. Several leachants were compared (sulfuric, hydrochloric and nitric acids, at 2 M H+ concentration), at temperatures of 25ºC and 90ºC and 4 hours of reaction time. Sulfuric acid leaching was not very promising concerning metals dissolution being only effective for iron. Hydrochloric acid allowed the leaching up to 60% of tin and about 50% of lead, as well as the iron. Nitric acid was the most efficient leachant due to its oxidizing properties. Recoveries of 90% or more for copper, iron, nickel and zinc were achieved at the higher temperature. Lead was also dissolved (up to 80%), as well as silver (more than 70%). These results show that the hydrometallurgical recovery of most of the metals present in PCB’s scrap is a technically feasible alternative that shall be considered and evaluated

Extraction of bixin from annatto seeds using supercritical carbon dioxide

The solubility of 93% pure bixin in supercritical carbon dioxide (SC-CO2) and of the bixin present in annatto seeds (Bixa orellana L.) was measured. For the seeds, the measurements were made in a temperature range from 30 to 50ºC and pressure between 10 and 35 MPa and for the pure bixin, at 40ºC from 10 to 35 MPa. The main pigments of annatto seeds are bixin and norbixin, but the extracts only showed the presence of cis and trans-bixin, indicating that norbixin is not soluble in SC-CO2. The annatto seeds used in the experiments contained about 2.7% bixin and 3.1% oil. In the seeds, the crossover point of solubility was at about 28 MPa and values for solubility were about ten times higher than those of the pure bixin, giving evidence that the oil acted as a co-solvent with the CO2.FAPES

Efeitos do calor e fontes tolerância ao florescimento precoce em variedades de alface do tipo americana

bitstream/item/81821/1/cot-88.pd

Vacuum Polarization for a Massless Spin-1/2 Field in the Global Monopole Spacetime at Nonzero Temperature

In this paper we present the effects produced by the temperature in the renormalized vacuum expectation value of the zero-zero component of the energy-momentum tensor associated with massless left-handed spinor field in the pointlike global monopole spacetime. In order to develop this calculation we had to obtain the Euclidean thermal Green function in this background. Because the expression obtained for the thermal energy density cannot be expressed in a closed form, its explicit dependence on the temperature is not completely evident. So, in order to obtain concrete information about its thermal behavior, we develop a numerical analysis of our result in the high-temperature limit for specific values of the parameter $\alpha$ which codify the presence of the monopole.Comment: 22 pages, LaTex format, 5 figure