Medium wave DRM field trials in Brazil : initial results

5 p.: il.This paper describes the experimental setup and presents initial results of medium wave propagation measurements campaigns that are being carried out in Brazil. The experiment is part of a series of field trials that are being conducted by the Brazilian Government to evaluate the performance of DRM standard in this country, which includes campaigns at MW, HF and VHF frequency bands in the cities of São Paulo, Rio de Janeiro and Belo Horizonte. A hybrid signal, composed of an analog AM signal and a digital DRM signal, with the same content, were broadcasted in diurnal and nocturnal transmissions. The results presented here include daytime and nighttime statistics of the measurements performed in São Paulo

Medium wave DRM field trials in Brazil : daytime result’s

5 p.: il.The Digital Radio Mondiale (DRM) system broadcasts audio in the frequency band below 174 MHz [1]. In this experiment, designed to evaluate the DRM system performance in urban areas in Brazil, a hybrid signal composed of an analog AM signal and a digital DRM signal, with the same content, were broadcasted in diurnal and nocturnal transmissions. This paper describes the experimental setup and presents initial results of medium wave propagation measurements campaigns that are being carried out in Brazil. The experiment is part of a series of field trials that are being conducted by the Brazilian Government to evaluate the performance of DRM standard, which includes campaigns at MW, HF and VHF frequency bands in the cities of São Paulo, Rio de Janeiro and Belo Horizonte. The results of São Paulo campaign with Radio Cultura AM are presented in this article

Medições de propagação em ondas médias do sistema rádio digital DRM em São Paulo

2 f. : il.O Inmetro, em ação conjunta com o Ministério das Comunicações, Anatel e INCT-CSF (Instituto Nacional de Ciência e Tecnologia de Comunicação sem Fio) está realizando testes para avaliação do padrão de rádio digital europeu DRM (Digital Radio Mondiale), para apoio ao processo de escolha do padrão brasileiro de radiodifusão sonora digital. Os testes consistem em medições em campo do sistema DRM na faixa de transmissão AM (ondas medias), para avaliação do desempenho e verificação de área de cobertura deste sistema digital. As medições foram realizadas com o laboratório móvel do Inmetro em São Paulo e no Rio de Janeiro, que possuem características de densa urbanização. Este artigo apresenta os resultados iniciais das medições em São Paulo da faixa de AM em pontos fixos, com transmissor DRM instalado na estação da Radio Cultura AM (1200 kHz)

Cytotoxicity of Extracts from <i>Petiveria alliacea</i> Leaves on Yeast

Petiveria alliacea L. is a plant used in traditional medicine harboring pharmacological properties with anti-inflammatory, antinociceptive, hypoglycemiant and anesthetic activities. This study assessed the potential cytotoxic, genotoxic and mutagenic effects of ethanolic extract of P. alliacea on Saccharomyces cerevisiae strains. S. cerevisiae FF18733 (wild type) and CD138 (ogg1) strains were exposed to fractioned ethanolic extracts of P. alliacea in different concentrations. Three experimental assays were performed: cellular inactivation, mutagenesis (canavanine resistance system) and loss of mitochondrial function (petites colonies). The chemical analyses revealed a rich extract with phenolic compounds such as protocatechuic acid, cinnamic and catechin epicatechin. A decreased cell viability in wild-type and ogg1 strains was demonstrated. All fractions of the extract exerted a mutagenic effect on the ogg1 strain. Only ethyl acetate and n-butanol fractions increased the rate of petites colonies in the ogg1 strain, but not in the wild-type strain. The results indicate that fractions of mid-polarity of the ethanolic extract, at the studied concentrations, can induce mutagenicity mediated by oxidative lesions in the mitochondrial and genomic genomes of the ogg1-deficient S. cerevisiae strain. These findings indicate that the lesions caused by the fractions of P. alliacea ethanolic extract can be mediated by reactive oxygen species and can reach multiple molecular targets to exert their toxicity