Genotype by environment interaction for 450-day weight of Nelore cattle analyzed by reaction norm models

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estrutura foliar de Loudetiopsis chrysothrix (Nees) Conert e Tristachya leiostachya Nees (Poaceae)

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

Studies on the adsorption and kinetics of photodegradation of a model compound for heterogeneous photocatalysis onto TiO2

An investigation was made on the adsorption and kinetics of photodegradation of potassium hydrogenphthalate in an aqueous suspension of TiO2. Two models, Langmuir and Freundlich, were used to describe the adsorption process and the model proposed by Langmuir-Hinshelwood (L-H) was employed to describe the kinetics of the photodecomposition reactions of hydrogenphthalate. The results of the adsorptions were fitted to the models proposed by Langmuir and Freundlich. Adsorption was found to be a function of the temperature, with adsorption capacity increasing from 2.4 to 4.5 mg/g when the temperature rose from 20 to 30 degrees C. The kinetic model indicates that the rate constant, k, of the first order reaction, is high in the 10.0 to 100 mg/l interval, which is coherent with the low value of the adsorption constant, K. The results fitted to the L-H model led to an equation that, within the range of concentrations studied here, theoretically allows one to evaluate the photodegradation rate. (c) 2005 Elsevier Ltd. All rights reserved.

A Survey of mid and large bodied mammals in Núcleo Caraguatatuba, Serra do Mar State Park, Brazil

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

Characterization and comparison of thermostability of purified beta-glucosidases from a mesophilic Aureobasidium pullulans and a thermophilic Thermoascus aurantiacus

The thermophilic fungus Thermoascus aurantiacus 179-5 and the mesophilic Aureobasidium pullulans ER-16 were cultivated in corn-cob by solid state fermentation for P-glucosidase production. After fermentation both enzymes were purified. The beta-glucosidases produced by the strains A. pullulans and T aurantiacus were most active at pH 4.0-4.5 and 4.5, with apparent optimum temperatures at 80 and 75 degrees C, respectively. Surprisingly, the enzyme produced by the mesophilic A. pullulans was stable over a wider range of pH (4.5-9.5 against 4.5-6.5) and more thermostable (98% after 1 h at 75 degrees C against 98% after 1 h at 70 degrees C) than the enzyme from the thermophilic T. aurantiacus. The t((1/2)) at 80 degrees C were 90 and 30 min for A. pullulans and T. aurantiacus, respectively. beta-Glucosidase thermoinactivation followed first-order kinetics and the energies of denaturation were 414 and 537 kJ mol(-1) for T. aurantiacus and A. pullulans, respectively. The result showed that beta-glucosidase obtained from the mesophilic A. pullulans is more stable than that obtained from the thermophilic T. aurantiacus. (C) 2007 Elsevier Ltd. All rights reserved.

A fish-based biotic integrity index for assessment of lowland streams in southeastern Brazil

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

Ecology of a stream from upper Paraná River basin inhabited by Aspidoras fuscoguttatus Nijssen & Isbrüker, 1976 (Siluriformes, Callichthyidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Riccati-type equations, generalised WZNW equations, and multidimensional Toda systems

We associate to an arbitrary Z-gradation of the Lie algebra of a Lie group a system of Riccati-type first order differential equations. The particular cases under consideration are the ordinary Riccati and the matrix Riccati equations. The multidimensional extension of these equations is given. The generalisation of the associated Redheffer-Reid differential systems appears in a natural way. The connection between the Toda systems and the Riccati-type equations in lower and higher dimensions is established. Within this context the integrability problem for those equations is studied. As an illustration, some examples of the integrable multidimensional Riccati-type equations related to the maximally nonabelian Toda systems are given.

Atomic Bose-Einstein condensation with three-body interactions and collective excitations

The stability of a Bose-Einstein condensed state of trapped ultra-cold atoms is investigated under the assumption of an attractive two-body and a repulsive three-body interaction. The Ginzburg-Pitaevskii-Gross (GPG) nonlinear Schrodinger equation is extended to include an effective potential dependent on the square of the density and solved numerically for the s-wave. The lowest collective mode excitations are determined and their dependences on the number of atoms and on the strength of the three-body force are studied. The addition of three-body dynamics can allow the number of condensed atoms to increase considerably, even when the strength of the three-body force is very small compared with the strength of the two-body force. We study in detail the first-order liquid-gas phase transition for the condensed state, which can happen in a critical range of the effective three-body force parameter.

Quantum state density and critical temperature in M-theory

We discuss the asymptotic properties of quantum states density for fundamental p-branes which can yield a microscopic interpretation of the thermodynamic quantities in M-theory. The matching of the BPS part of spectrum for superstring and supermembrane gives the possibility of getting membrane's results via string calculations. In the weak coupling limit of M-theory, the critical behavior coincides with the first-order phase transition in the standard string theory at temperature less than the Hagedorn's temperature T-H. The critical temperature at large coupling constant is computed by considering M-theory on manifold with topology R-9 circle times T-2. Alternatively we argue that any finite temperature can be introduced in the framework of membrane thermodynamics.

Nonlinear Schrodinger equation with power-law confining potential

Critical limits of a stationary nonlinear three-dimensional Schrodinger equation with confining power-law potentials (similar to r(alpha)) are obtained using spherical symmetry. When the nonlinearity is given by an attractive two-body interaction (negative cubic term), it is shown how the maximum number of particles N-c in the trap increases as alpha decreases. With a negative cubic and positive quintic terms we study a first order phase transition, that occurs if the strength g(3) of the quintic term is less than a critical value g(3c). At the phase transition, the behavior of g(3c) with respect to alpha is given by g(3c)similar to 0.0036+0.0251/alpha+0.0088/alpha(2).

Kinematical and nonlocality effects on the nonmesonic weak hypernuclear decay

We make a careful study about the nonrelativistic reduction of one-meson-exchange models for the nonmesonic weak hypernuclear decay. Starting from a widely accepted effective coupling Hamiltonian involving the exchange of the complete pseudoscalar and vector meson octets (pi, eta, K, rho, omega, K*), the strangeness-changing weak LambdaN --> NN transition potential is derived, including two effects that have been systematically omitted in the literature, or, at best, only partly considered. These are the kinematical effects due to the difference between the lambda and nucleon masses, and the first-order nonlocality corrections, i.e., those involving up to first-order differential operators. Our analysis clearly shows that the main kinematical effect on the local contributions is the reduction of the effective pion mass. The kinematical effect on the nonlocal contributions is more complicated, since it activates several new terms that would otherwise remain dormant. Numerical results for C-12(Lambda) and He-5(Lambda) are presented and they show that the combined kinematical plus nonlocal corrections have an appreciable influence on the partial decay rates. However, this is somewhat diminished in the main decay observables: the total nonmesonic rate, Gamma(nm), the neutron-to-proton branching ratio, Gamma(n)/Gamma(p), and the asymmetry parameter, a(Lambda). The latter two still cannot be reconciled with the available experimental data. The existing theoretical predictions for the sign of a(Lambda) in He-5(Lambda) are confirmed. (C) 2003 Elsevier B.V. All rights reserved.

Duality in noncommutative topologically massive gauge field theory revisited

We introduce a master action in non-commutative space, out of which we obtain the action of the non-commutative Maxwell-Chern-Simons theory. Then, we look for the corresponding dual theory at both first and second order in the non-commutative parameter. At the first order, the dual theory happens to be, precisely, the action obtained from the usual commutative self-dual model by generalizing the Chern-Simons term to its non-commutative version, including a cubic term. Since this resulting theory is also equivalent to the non-commutative massive Thirring model in the large fermion mass limit, we remove, as a byproduct, the obstacles arising in the generalization to non-commutative space, and to the first non-trivial order in the non-commutative parameter, of the bosonization in three dimensions. Then, performing calculations at the second order in the non-commutative parameter, we explicitly compute a new dual theory which differs from the non-commutative self-dual model and, further, differs also from other previous results and involves a very simple expression in terms of ordinary fields. In addition, a remarkable feature of our results is that the dual theory is local, unlike what happens in the non-Abelian, but commutative case. We also conclude that the generalization to non-commutative space of bosonization in three dimensions is possible only when considering the first non-trivial corrections over ordinary space.

Magnetic flux inversion in charged BPS vortices in a Lorentz-violating Maxwell-Higgs framework

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

SEMICLASSICAL VIOLATION of THE EQUIVALENCE PRINCIPLE IN THE GRAVITATIONAL LENSES REALM

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)