A proposal for a generalized canonical osp(1,2) quantization of dynamical systems with constraints

The aim of this paper is to consider a possibility of constructing for arbitrary dynamical systems with first-class constraints a generalized canonical quantization method based on the osp(1,2) supersymmetry principle. This proposal can be considered as a counterpart to the osp(1,2)-covariant Lagrangian quantization method introduced recently by Geyer, Lavrov and M\"ulsch. The gauge dependence of Green's functions is studied. It is shown that if the parameter m^2 of the osp(1,2) superalgebra is not equal to zero then the vacuum functional and S-matrix depend on the gauge. In the limit $m\to 0$ the gauge independence of vacuum functional and S - matrix are restored. The Ward identities related to the osp(1,2) symmetry are derived.Comment: Revised version. To appear in Mod.Phys.Lett.

Solos do município de Pariconha - Estado de Alagoas

bitstream/CNPS-2010/14932/1/comtec35-2006-pariconha.pd

Solos do município de Delmiro Gouveia - Estado de Alagoas

bitstream/CNPS-2010/14931/1/comtec36-2006-delmiro-gouveia.pd

An Early Universe Model with Stiff Matter and a Cosmological Constant

In the present work, we study the quantum cosmology description of a Friedmann-Robertson-Walker model in the presence of a stiff matter perfect fluid and a negative cosmological constant. We work in the Schutz's variational formalism and the spatial sections have constant negative curvature. We quantize the model and obtain the appropriate Wheeler-DeWitt equation. In this model the states are bounded therefore we compute the discrete energy spectrum and the corresponding eigenfunctions. In the present work, we consider only the negative eigenvalues and their corresponding eigenfunctions. This choice implies that the energy density of the perfect fluid is negative. A stiff matter perfect fluid with this property produces a model with a bouncing solution, at the classical level, free from an initial singularity. After that, we use the eigenfunctions in order to construct wave packets and evaluate the time-dependent expectation value of the scale factor. We find that it oscillates between maximum and minimum values. Since the expectation value of the scale factor never vanishes, we confirm that this model is free from an initial singularity, also, at the quantum level.Comment: 12 Pages, 4 Figures. Final version. Accepted for publication in the Proceedings of the 8th Friedmann Seminar, Rio de Janeiro, 2011. We restricted our attention to treat the case where the stiff matter has negative energy eigenvalues, following the referee's suggestio

FINITE SIZE SCALING FOR FIRST ORDER TRANSITIONS: POTTS MODEL

The finite-size scaling algorithm based on bulk and surface renormalization of de Oliveira (1992) is tested on q-state Potts models in dimensions D = 2 and 3. Our Monte Carlo data clearly distinguish between first- and second-order phase transitions. Continuous-q analytic calculations performed for small lattices show a clear tendency of the magnetic exponent Y = D - beta/nu to reach a plateau for increasing values of q, which is consistent with the first-order transition value Y = D. Monte Carlo data confirm this trend.Comment: 5 pages, plain tex, 5 EPS figures, in file POTTS.UU (uufiles

Detrimental effect of rutin on Anticarsia gemmatalis.

Behavioral and nutritional effect of rutin (quercetin 3-O-rutinosídeo) on Anticarsia gemmatalis Hübner (Lep.: Noctuidae), a major soybean defoliator in Brazil, was evaluated from the third instar to pupation. Rutin is one of the flavonol glycosides identified in the leaves of the wild soybean PI 227687. Larval weight and amount of ingested food decreased as rutin concentration in the diet increase. An interactive effect between feeding time and diet (treatment) was observed on insect growth; when larvae fed on pure-diet, feeding time elongation resulted in heavier pupae. Differently, the weight of larvae fed on rutin-diet remained almost stable, in spite of eating for longer. A. gemmatalis growth was negatively influenced by rutin-diet not only by feeding deterrence but also by post-ingestive effect on insect growth, since after adjustment of pupal weight by the amount of ingested food (covariate), the effect of diet remained significant. Rutin negatively influenced A. gemmatalis growth as result of pre-ingestive effect, indicated by reduction in food consumption, and post-ingestive effect, indicated by lower conversion of ingested food into body mass and food assimilation

Solos do campo experimental da Embrapa Algodão, em Patos-PB: levantamento detalhado e potencial edáfico.

bitstream/CNPS/11833/1/bpd17_2002_patos_pb.pd

Riemann-Cartan Space-times of G\"odel Type

A class of Riemann-Cartan G\"odel-type space-times are examined in the light of the equivalence problem techniques. The conditions for local space-time homogeneity are derived, generalizing previous works on Riemannian G\"odel-type space-times. The equivalence of Riemann-Cartan G\"odel-type space-times of this class is studied. It is shown that they admit a five-dimensional group of affine-isometries and are characterized by three essential parameters $\ell, m^2, \omega$: identical triads ($\ell, m^2, \omega$) correspond to locally equivalent manifolds. The algebraic types of the irreducible parts of the curvature and torsion tensors are also presented.Comment: 24 pages, LaTeX fil

Estado atual de degradação das terras nas margens do rio São Francisco nos municípios de Petrolina, Lagoa Grande e Santa Maria da Boa Vista.

O estudo dos solos e ambientes que ocorrem na paisagem nordestina tem assumido indiscutível importância nestas últimas décadas. O acentuado progresso da ciência trouxe novos e fundamentais conhecimentos que permitiram, em poucos anos, detalhar e aprofundar o estudo científico da pedologia a partir da integração de informações sobre o meio ambiente. Atualmente, o grande desafio é equacionar a atividade produtiva com a geração de renda e o desenvolvimento sustentável, compatibilizando interesses ambientais, econômicos e sociais. Para isso, o conhecimento dos recursos naturais é fundamental para qualquer etapa do planejamento e do desenvolvimento sustentável, já que proporciona informações referenciais que ajudam na exploração racional destes recursos, principalmente do solo e da água. O presente texto aborda a situação atual das terras ribeirinhas nos municípios de Petrolina, Lagoa Grande e Santa Maria da Boa Vista, no Estado de Pernambuco, decorrente do uso agrícola e outros impactos antrópicos, visando fornecer subsídios para projetos estruturantes de recomposição da mata ciliar do Rio São Francisco nos referidos municípios. É apresentada a situação atual das terras e os principais problemas relacionados às mesmas

Reference Structure Model for Degree Alert Classification During Seasonal Hydrological Events for Humanitarian Assistence in the Brazilian Amazon

AbstractRecent events in the rivers of the Amazon region show the distinct need for concern in this region and the vulnerability of the Amazonian people in regards to these events. Organizations for humanitarian aid developed procedures in the Amazon region. But to what extent are these actions effective if little is done prior to disasters? This work seeks to develop a frame of reference for classifying alertness in cities likely to suffer from flooding and ebbing of the hydrographic network in the Amazon Basin. The objective is to serve warning to the riverside communities in the state of Amazonas, establish future provisions of supplies and to form a solid database of information concerning the needs and impacts of these events, hence creating a historical record