Perfect category-graded algebras

In a perfect category every object has a minimal projective resolution. We give a criterion for the category of modules over a categorygraded algebra to be perfect.Comment: A sufficient condition is replaced by a criterion. Several references added. 17 page

Renormalized coordinate approach to the thermalization process

We consider a particle in the harmonic approximation coupled linearly to an environment. modeled by an infinite set of harmonic oscillators. The system (particle--environment) is considered in a cavity at thermal equilibrium. We employ the recently introduced notion of renormalized coordinates to investigate the time evolution of the particle occupation number. For comparison we first present this study in bare coordinates. For a long ellapsed time, in both approaches, the occupation number of the particle becomes independent of its initial value. The value of ocupation number of the particle is the physically expected one at the given temperature. So we have a Markovian process, describing the particle thermalization with the environment. With renormalized coordinates no renormalization procedure is required, leading directly to a finite result.Comment: 16 pages, LATEX, 2 figure

Produção animal em sistema intensivo de pastagens de Panicum maximum cv. Tânzania.

O objetivo foi avaliar os ganhos de peso por animal e por área em pastos de capim-tanzânia no período das águas, sob dois níveis de fertilidade (NFB V% = 40-50, P = 4-8 mg/l e K = 60-80 mg/l e NFA V% = 50-70, P = 8-12 mg/l e K = 80-100 mg/l) e dois níveis de adubação nitrogenada (150 e 300 kg de N/ha/ano)