Perturbative breaking of the pseudospin symmetry in the relativistic harmonic oscillator

We show that relativistic mean fields theories with scalar S, and vector V, quadratic radial potentials can generate a harmonic oscillator with exact pseudospin symmetry and positive energy bound states when S = -V. The eigenenergies are quite different from those of the non-relativistic harmonic oscillator. We also discuss a mechanism for perturbatively breaking this, symmetry by introducing a tensor potential. Our results shed light into the intrinsic relativistic nature of the pseudospin symmetry, which might be important in high density systems such as neutron stars.

Crystallization of nordstrandite in ethylene glycol water solutions: electron microscopic studies

The present work shows the growth of nordstrandile microcrystals observed by transmission and scanning electron microscopy. Nordstrandite was synthesised from non-crystalline aluminium hydroxide reacted in 20% ethylene glycol/water solution, at room temperature. This material was characterized by TEM, SEM, SAED, XRD and EDS/TEM, during six month and revealed the formation and growth of nordstrandite. Fibrillar pseudoboehmite is the only aluminium hydroxide which could be identified during the first two weeks. The nuclei grow, from complete dissolution/recrystallization of pseudoboehmite fibrils, into platy rectangular microscrystals of nordstrandite. Some tabular microcrystals recrystallise, forming after six months only the mufti-point nordstrandite stars. This electron-optical study suggest that the star shape results from the overlapping of rectangular plates, and pseudoboehmite fibrils act as the precursor of nordstrandite crystallisation in ethylene glycol/water solution.

Competitividad centroamericana

Incluye Bibliografía

Otimização e estudo do comportamento do solo-cimento auto-adensável

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos do meio nuclear denso sobre o mecanismo de pólo do píon ('gamagamaseta'pi''POT.0setaniuniu''BARRA')

Pós-graduação em Física - IFT

Formação de compostos de alumínio por associação radioativa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Nietzsche e a inflexão filosofica rumo ao mundo mítico: leituras de Heráclito

Pós-graduação em Filosofia - FFC

Mulheres em transgressão: a visibilidade da voz feminina em Vozes do deserto de Nélida Pinõn

Pós-graduação em Letras - FCLAS

Latin America’s competitive position in knowledge-intensive services trade

This study presents a dynamic analysis of Latin America's competitiveness in trade in knowledge-intensive services. The methodology used to undertake this analysis is based on the Tradecan approach developed by the Economic Commission for Latin America and the Caribbean (ECLAC), which provides a means of assessing different countries' competitiveness by looking at their exports to the fastest-growing markets. (In the past, it has usually been applied primarily to exports of goods.) The results suggest that, although some Latin American countries have made inroads in knowledge-intensive service segments and have comparative advantages in them, the percentage of "rising stars" (dynamic sectors in which a country or region is gaining in market share) is still low, while there is a high percentage of "missed opportunities" (dynamic sectors in which a country or region is losing market share). This points up the existence of areas in which the region's competitive position is weak and in which policies are needed to leverage its competitive advantages and remove the obstacles that are holding it back from establishing a more advantageous position in knowledge-intensive service markets.

Um estudo histórico perceptual: a bandeira brasileira sem o Brasil

Pós-graduação em Artes - IA

Férmions em referenciais acelerados: desintegração de prótons e outras aplicações

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Leituras intertextuais de O Tetraneto del-rei de Haroldo Maranhão

O presente trabalho tem como objeto de investigação a escrita de Haroldo Maranhão, buscando compreender os aspectos que influenciaram na formação deste autor, bem como a particularidade de sua escrita, repleta de traços eruditos e, paralelamente, apresentando expressões obscenas e de valor popular. Para tanto, pautou-se a presente análise na obra O Tetraneto Del-Rei, que apresenta com riqueza de detalhes, aspectos relacionados ao período de nossa colonização, porém sob um prisma diferenciado e reinterpretativo, a partir dos diversos signos e elementos manifestados na obra de Haroldo. Converge, portanto, ao caráter reinterpretativo, a figura do Torto, colonizador português que protagoniza momentos de fraqueza, angústia, desejos e medos, sentimentos esses que não constam em obras que disseminaram em prosa e verso o imaginário de um herói. Como subsídio conceitual e literário, apresentamos autores precursores a Haroldo Maranhão, buscando identificar as relações deste com o estilo daqueles. Por fim, a investigação buscou demonstrar a presença de três elementos intertextuais na obra O Tetraneto Del-Rei, a saber: releituras da colonização, o significado do chapéu e as interpretações do obsceno.

The formation of AlF by radiative association

The formation of the aluminium monofluoride molecule AlF by radiative association of the Al and F atoms is estimated. The radiative association of Al(P-2) and F(P-2) atoms is found to be dominated by the approach along the A(1) potential energy curve accompanied by spontaneous emission into the X-1 Sigma(+) ground state of the AlF. For temperatures ranging from 300 to 14 000 K, the rate coefficients are found to vary from 1.35 x 10(-17) to 9.31 x 10(-16) cm(3) s(-1), respectively. These values indicate that only a small amount of AlF molecules can be formed by radiative association in the inner envelope of carbon-rich stars and other hostile environments.

Taxonomic assessment and enzymes production by yeasts isolated from marine and terrestrial Antarctic samples

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Implementation of an F-statistic all-sky search for continuous gravitational waves in Virgo VSR1 data

We present an implementation of the F-statistic to carry out the first search in data from the Virgo laser interferometric gravitational wave detector for periodic gravitational waves from a priori unknown, isolated rotating neutron stars. We searched a frequency f(0) range from 100 Hz to 1 kHz and the frequency dependent spindown f(1) range from -1.6(f(0)/100 Hz) x 10(-9) Hz s(-1) to zero. A large part of this frequency-spindown space was unexplored by any of the all-sky searches published so far. Our method consisted of a coherent search over two-day periods using the F-statistic, followed by a search for coincidences among the candidates from the two-day segments. We have introduced a number of novel techniques and algorithms that allow the use of the fast Fourier transform (FFT) algorithm in the coherent part of the search resulting in a fifty-fold speed-up in computation of the F-statistic with respect to the algorithm used in the other pipelines. No significant gravitational wave signal was found. The sensitivity of the search was estimated by injecting signals into the data. In the most sensitive parts of the detector band more than 90% of signals would have been detected with dimensionless gravitational-wave amplitude greater than 5 x 10(-24).