Objetivou-se avaliar o consumo de forragem e o desempenho de ovinos mantidos em pastagem de capim-aruana, submetidos a porcentagens crescentes de proteína bruta (PB) no suplemento, na época seca. Vinte borregos da raça Santa Inês foram utilizados em delineamento inteiramente ao acaso, com cinco tratamentos e quatro repetições. Os suplementos foram fornecidos em 1,0% do peso corporal, nas porcentagens de 0, 15, 20, 25 e 30%. O aumento de proteína bruta influenciou o consumo total de matéria seca (kg/dia) e a porcentagem do peso vivo, com valores máximos estimados de 1.296g (3,2% de MS) com 21,48 e 21,89% de PB no suplemento, respectivamente. O consumo de forragem máximo, estimado de 893g/dia, ocorreu com a PB de 21,5%. O aumento de PB nos suplementos resultou em efeito quadrático sobre o ganho médio diário, com valor máximo de 104g/dia com a PB de 23% no suplemento. Recomenda-se o uso de suplementos múltiplos com 21 a 23% de PB fornecidos na proporção de 1% do peso corporal (PC) para ovinos mantidos em pastos de capim-aruana na época seca.

The aim of this study was to evaluate the forage intake and grazing sheep performance keep on Aruana grass subjected to increasing crude protein (CP) levels in the supplement on dry season. Twenty Santa Ines male lambs were used, with initial body weight of 31.80kg by a completely randomized design with five treatments and four replications. The supplements were provided daily at 1% of body weight, with protein levels of 0, 15, 20, 25 and 30%. The increase of the crude protein levels promoted a squarely effect on dry matter intake (kg/day and % of BW), with maximum estimated values of 1296g and 3.2% of DM in CP levels of 21.48 and 21.89, respectively. The maximum forage intake estimated of 893g/day occurred in CP level de 21.51%. The increased of crude protein level in supplements increased squarely the average daily gain, with a maximum of 104g/day, for the 23% crude protein in the supplement. Thus, the use of the multiple supplements supplied in 1% of body weight with CP levels ranged 21 a 23% is indicated for sheep grazing Aruana grass on dry season.

We obtain exact solutions for the Schrödinger-Pauli matrix equation for a neutral particle of spin 1/2 in a magnetic eld with a field gradient. The analytical wavefunctions are written on the symmetry plane Y = 0, which contains the incident and splitted beams, in terms of the Airy functions. The time-evolution of the probability densities, |<FONT FACE=Symbol>Y+|</FONT>² and |<FONT FACE=Symbol>Y-|² </FONT>, and the eigenenergies are calculated. These include a small contribution from the field gradient, alpha, proportional to (alpha<img src="http:/img/fbpe/bjp/v31n3/sh.gif">)2/3, which amounts to equal energy displacements on both magnetic levels. The results are generalized for spin S = 3/2, and in this case we found that the m = ±1/2 and m = ±3/2 magnetic sublevels are unequaly splitted by the field gradient, being the difference in energy of the order 0.4 MHz. Replacing real experimental parameters we obtained a spatial splitting of the spin up and spin down states of the order deltaz ~ 4 mm, in accordance to a real Stern-Gerlach experiment.

The motion of a particle with charge q and mass m in a magnetic field given by B = kB0 + B1 [icos(omegat) + jsin(omegat)] and an electric field which obeys <FONT FACE="Symbol">Ñ</FONT> ×E = -<FONT FACE="Symbol">¶</FONT>B/<FONT FACE="Symbol">¶</FONT>t is analysed classically and quantum-mechanically. The use of a rotating coordinate system allows the analytical derivation of the particle classical trajectory and its laboratory wavefunction. The motion exhibits two resonances, one at omega = omegac = -qBo/m, the cyclotron frequency, and the other at omega = omegaL = -qBo/2m, the Larmor frequency. For omega at the first resonance frequency, the particle acquires a simple closed trajectory, and the effective hamiltonian can be interpreted as that of a particle in a static magnetic field. In the second case a term corresponding to an effective static electric field remains, and the particle orbit is an open line. The particle wave function and eigenenergies are calculated.

The similarity between the electron equation of motion in electric and magnetic fields and the Bloch equations for nuclear magnetic moments in a magnetic field leads to a novel resonance phenomenon involving the electrical current. This suggests a new experimental technique for the investigation of transport properties in conducting materials. In this work we propose a new set of Bloch Equations for the electrical current with different electron-electron and electron-lattice scattering rates and discuss the consequences of their solutions to the study of the electronic properties of conducting materials. We outline the experimental conditions for detecting electrical current resonance and estimate some relevant experimental parameters for the observation of current echoes and free current decays.