Study of magnetic switch for surface plasmon-polariton circuits

In recent years, technological development has focused on the construction of ever smaller devices, characterized by dimensions limited to the nanometer order and by a very low energy requirement to be able to function. This allows them to be integrated into chips, which are then able to perform many tasks from filtering to computation. Here, we present a magnetic switch capable of working with surface plasmon polaritons

Estratégias de comunicação em agricultura de precisão

A popularização do conhecimento científico é a ponte de acesso da sociedade aos avanços técnico-científicos. O desafio está em ampliar os meios, canais e processos de relacionamento e informação com a sociedade e decodificar os assuntos científicos para um formato que torne o conhecimento acessível. A Rede Agricultura de Precisão da Embrapa tem utilizado estratégias de comunicação nas tradicionais e novas mídias, como forma de buscar a aproximação com diversos públicos, contribuindo com a construção de uma consciência crítica da sociedade brasileira. O objetivo deste artigo é o de apresentar e avaliar os resultados destas estratégias como a homepage, vídeos didáticos e reportagens na mídia. A divulgação dos resultados da pesquisa tem sido uma forma eficiente da equipe do projeto aproximar-se da sociedade, mostrando a geração de conhecimento em AP feita no País pela Embrapa e seus parceiros. Contribuindo com o fortalecimento e divulgação do conceito de AP como ferramenta gerencial para produtores e provedores de serviços. Também é uma forma de prestação de contas à sociedade, indicando o destino dos recursos alocados para pesquisa

Ontogenetic differences in ethanol's motivational properties during infancy

Pairing a conditioned stimulus (CS) with ethanol generally produces aversion for that CS in adult rodents. However, infant rats (PD1-PD3) exposed to ethanol demonstrate appetitive reinforcement to ethanol (Petrov et al., 2003; Nizhnikov et al., 2006a). This sensitivity to the appetitive properties of ethanol during infancy may be transient, as during the second postnatal week rat pups tend to exhibit conditioned aversions to flavors paired with ethanol. The present study examined changes in the motivation properties of ethanol through ontogeny and the neurobiology underlying these changes. Rat pups were exposed to a taste conditioning procedure on PD4 or PD12. Rat pups were intraorally infused with 2.5% of their body weight of saccharin solution (0.1%) and immediately after injected intraperitoneolly (i.p.) with one of six doses of ethanol (0.0–2.0 g/kg). A day later pups were given saccharine infusions and percent body weight gain was used as an index of ethanol’s reinforcing effects. PD4 pups expressed appetitive reinforcement to ethanol, as indicated by greater saccharin intake, as compared to control counterparts and to the older PD12 pups. Subsequent experiments revealed that PD4 pups were less sensitive to the aversive properties of the drug than PD12 pups. The older pups found high doses of ethanol aversive while PD4 rat pups did not condition aversions to this dose of ethanol after a single trial. A similar pattern of results was observed between the low doses of ethanol and the highest doses of a kappa opioid agonist. The PD12 animals did not condition to the kappa opioid agonist, while the younger rats expressed an appetitive response. These results illustrate an ontogenetic change in the motivational properties of ethanol, with sensitivity to its appetitive properties declining and responsiveness to the aversive properties increasing with age during early infancy