The accidental release of 26 African honey bee queens (Apis mellifera scutellata) in Brazil in 1957 was the beginning of the Africanization process of honey bees in South America. This was highly impacting on beekeeping across the continent, because, despite being more productive, African honey bees were very aggressive. Many attempts to cross European x African bees were done in order to obtain less aggressive bees (Michener, 1975). There are slight morphological differences between African and European honeybees. In terms of beekeeping management, however, behavioral differences are more important. Besides stinging, another important difference is hygienic behavior. African honeybees are known to be more effective in eliminating dead larvae and pupae than their European counterparts (Guzman-Novoa et al., 1999). Despite the Africanization, there are still regions with a predominance of European subspecies. For example, in Argentina, there was a significant introduction of European subspecies in highly saturated Africanized honey bee regions in order to slow down the Africanization process. This provided more European gene frequency in

realizado na Casa do Médico, de 7 a 10 de Abril de 2010, tendo como membros da

The cerebellar Purkinje cell is among the largest and most complex neurons in the mammalian brain. The 150,000 to 175,000 granule cell inputs received by each Purkinje cell (Harvey and Napper, 1991) constitute the most massive synaptic convergence found on any neuron in the brain (Shepherd, 1990). Purkinje cells are also distinguished by high densities of Ca2+ channels on the dendrite and by a complex apparatus controlling cytoplasmic Ca2+ concentrations, e.g., with cytoplasmic Ca2+ stores possessing IP3 and ryanodine receptors (Brorson et al., 1991), metabotropic receptors (Llano et al., 1991; Staub et al., 1992) and Ca2+ inflow through the Ca2+ channels (Hockberger et al., 1989; Lev-Ram et al., 1992). Numerous physiological (Llinás and Sugimori, 1992) and biochemical studies (Ito, 1984) have provided the neuroscience community with a wealth of details on the firing properties of Purkinje cells in vitro and on the identity and kinetics of synaptic and ionic channels, but an integrated view of how all these

A lo largo de los años ha realizado diferentes estudios con el objetivo de evaluar los efectos fisiológicos resultantes del consumo de carbohidratos de lenta digestion, los llamados de bajo índice glucémico (IG) y sus efectos en la oxidación de la grasa, en el intento de encontrar estrategias dietéticas que faciliten la obtención de una composición corporal satisfac-toria. De acuerdo a lo expuesto, el objetivo de la investiga-ción fue analizar estudios en que se haya evaluado en qué medida el consumo de una dieta con bajo IG afecta a la com-posición corporal, dando énfasis al efecto de la oxidación de la grasa. La investigación se hizo por medio de búsqueda en Internet de artículos en inglés y/o portugués, publicados desde 1995, y para eso se usó las palabras llave glycemic index, glycemic load, glycaemic index, glycaemic load, body fat, body composition, fat oxidation. Fueron incluidos artícu-los que evaluaban ensayos clínicos en animales y/o huma-nos. Los datos fueron recogidos y estudios utilizando datos encontrados en los sitios: Web of Science, Science Direct y Pubmed. Se averiguó que los resultados en la mayoría de los estudios señalan que el consumo de una dieta de bajo IG se produce una baja respuesta insulínica, aumentando la oxi-dación de la grasa corporal. Estos resultados indican que la ingestión de dieta de bajo IG es una estrategia importante para ser utilizada en la prevención y control de la obesidad y también de las enfermedades crónicas a ella asociada.

The alpha rhythm is the most prominent feature observed in the human electroencephalogram (EEG), and is strongest when the subject is in an eyes-closed relaxed state (Niedermeyer and Lopes da Silva, 2004). It is suppressed by attention or mental effort,

rhythm frequency for any one cat being below 5%. α rhythms were most prominent when the animal assumed a motionless “sphinx ” position with eyes closed and occurred in discrete episodes lasting about 2–20 s (mean duration: 6.8 ± 0.9 s; n = 40 episodes). As previously described in dogs (Lopes da Silva et

Abstract: In this report we present a mathematical analysis of a simple model of a cortical column. We first recall some known biological facts about cortical columns. We then present a mathematical model of such a column, developed by a number of people including Lopes Da Silva, Jansen, Rit

by a large variability in dominant frequencies (Pfurtscheller & Lopes da Silva, 1999; Fingelkurts et

The EEG is traditionally categorized into a handful of different frequency bands (δ, θ, α, β, γ; c.f. Schomer and Lopes da Silva, 2011). This implies that EEG frequencies do not represent an unstruc-tured continuum. But what could be the reasons for that? One obvious reason is that frequency bands

the frequency of oscillations. In this work we extended the classical nonlinear lumped-parameter model of alpha rhythms, initially developed by Lopes da Silva and colleagues [Kybernetik 15 (1974) 27], to generate more complex dynamics. We show that the whole spectrum of MEG/EEG signals can be reproduced within