992 resultados para ITU-R 1546-5
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Concert Program
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Concentrations of total (R) + (S) and of the enantiomers (R) and (S) of thioridazine and metabolites were measured in 21 patients who were receiving 100 mg thioridazine for 14 days and who were comedicated with moclobemide (450 mg/day). Two patients were poor metabolizers of dextromethorphan and one was a poor metabolizer of mephenytoin. Cytochrome P450IID6 (CYP2D6) is involved in the formation of thioridazine 2-sulfoxide (2-SO) from thioridazine and also probably partially in the formation of thioridazine 5-sulfoxide (5-SO), but not in the formation of thioridazine 2-sulfone (2-SO2) from thioridazine 2-SO. Significant correlations between the mephenytoin enantiomeric ratio and concentrations of thioridazine and metabolites suggest that cytochrome P450IIC19 could contribute to the biotransformation of thioridazine into yet-unknown metabolites, other than thioridazine 2-SO, thioridazine 2-SO2, or thioridazine 5-SO. An enantioselectivity and a large interindividual variability in the metabolism of thioridazine have been shown: measured (R)/(S) ratios of thioridazine, thioridazine 2-SO fast eluting (FE), thioridazine 2-SO slow eluting (SE), thioridazine 2-SO (FE+SE), thioridazine 2-SO2, thioridazine 5-SO(FE), and thioridazine 5-SO(SE) were (mean +/- SD) 3.48 +/- 0 .93 (range, 2.30 to 5.80), 0.45 +/- 0.22 (range, 0.21 to 1.20), 2.27 +/- 8.1 (range, 6.1 to 40.1), 4.64 +/- 0.68 (range, 2.85 to 5.70), 3.26 +/- 0.58 (range, 2.30 to 4.30), 0.049 +/- 0.019 (range, (0.021 to 0.087), and 67.2 +/- 66.2 (range, 16.8 to 248), respectively. CYP2D6 is apparently involved in the formation of (S)-thioridazine 2-SO(FE), (R)-thioridazine 2-SO(SE), and also probably (S)-thioridazine 5-SO(FE) and (R)-thioridazine 5-SO(SE).
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A adoção de sistemas digitais de radiodifusão sonora, que estão em fase de testes no país, permite realizar novos estudos visando um melhor planejamento para a implementação dessas novas emissoras. O que significa reavaliar os principais modelos de radiopropagação existentes ou propor novas alternativas para atender as demandas inerentes dos sistemas digitais. Os modelos atuais, conforme Recomendações ITU-R P. 1546 e ITU-R P. 1812, não condizem fielmente com a realidade de algumas regiões do Brasil, principalmente com as regiões de clima tropical, como a Região Amazônica, seja pelo elevado índice pluviométrico seja pela vasta flora existente. A partir dos modelos adequados ao canal de propagação, torna-se viável desenvolver ferramentas de planejamento de cobertura mais precisas e eficientes. A utilização destas ferramentas é cabível tanto para a ANATEL, para a elaboração dos planos básicos de distribuição de canais quanto para os radiodifusores. No presente trabalho é apresentada uma metodologia utilizando a inteligência computacional, baseada em Inferênciass Baysianas, para predição da intensidade de campo elétrico, a qual pode ser aplicada ao planejamento ou expansão de áreas de cobertura em sistemas de radiodifusão para frequências na faixa de ondas médias (de 300 kHz a 3MHz). Esta metodologia gera valores de campo elétrico estimados a partir dos valores de altitude do terreno (através de análises de tabelas de probabilidade condicional) e estabelece a comparação destes com valores de campo elétrico medidos. Os dados utilizados neste trabalho foram coletados na região central do Brasil, próximo à cidade de Brasília. O sinal transmitido era um sinal de rádio AM transmitido na frequência de 980 kHz. De posse dos dados coletados durante as campanhas de medição, foram realizadas simulações utilizando tabelas de probabilidade condicional geradas por Inferências Bayesianas. Assim, é proposto um método para predizer valores de campo elétrico com base na correlação entre o campo elétrico medido e altitude, através da utilização de inteligência computacional. Se comparados a inúmeros trabalhos existentes na literatura que têm o mesmo objetivo, os resultados encontrados neste trabalho validam o uso da metodologia para determinar o campo elétrico de radiodifusão sonora em ondas médias utilizando Inferências Bayesianas.
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We identified syntaxin 5 (Stx5), a protein involved in intracellular vesicle trafficking, as a novel interaction partner of the very low density lipoprotein (VLDL)-receptor (VLDL-R), a member of the LDL-receptor family. In addition, we investigated the effect of Stx5 on VLDL-R maturation, trafficking and processing. Here, we demonstrated mutual association of both proteins using several in vitro approaches. Furthermore, we detected a special maturation phenotype of VLDL-R resulting from Stx5 overexpression. We found that Stx5 prevented Golgi-maturation of VLDL-R, but did not cause accumulation of the immature protein in ER to Golgi compartments, the main expression sites of Stx5. Rather more, abundantly present Stx5 was capable of translocating ER-/N-glycosylated VLDL-R to the plasma membrane, and thus was insensitive to BFA treatment and incubation at low temperature. Based on our findings, we postulate that Stx5 can directly bind to the C-terminal domain of VLDL-R, thereby influencing the receptor’s glycosylation, trafficking and processing characteristics. Resulting from that, we further suggest that Stx5, which is highly expressed in neurons along with VLDL-R, might play a role in modulating the receptor’s physiology by participating in a novel/undetermined alternative pathway bypassing the Golgi apparatus.
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The antenna presented in this article will be developed for satellite communications onboard systems based on the recommendations ITU-R S.580-6 and ITU-R S.465-5. The antenna consists of printed elements grouped in an array, this terminal works in a frequency band from 7.25 up to 8.4 GHz (14.7% of bandwidth), where both bands, reception (7.25 - 7.75 GHz) and transmission (7.9 - 8.4 GHz), are included simultaneously. The antenna reaches a gain about 31 dBi, and it has a radiation pattern with a beamwidth smaller than 10° and a dual circular polarization. The antenna has the capability to steer in elevation from 90° to 40° electronically and 360° in azimuth with a motorized junction.
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This work provides the development of an antenna for satellite communications onboard systems based on the recommendations ITU-R S.580-6 [1] and ITU-R S.465-5 [2]. The antenna consists of printed elements grouped in an array, working in a frequency band from 7.25 up to 8.4 GHz (15% of bandwidth). In this working band, transmission and reception are included simultaneously. The antenna reaches a gain about 31 dBi, has a radiation pattern with a beam width smaller than 10oand dual circular polarization. It has the capability to steer in elevation through a Butler matrix to 45
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An antenna which has been conceived as a portable system for satellite communications based on the recommendations ITU-R S.580-6 [1] and ITU-R S.465-5 [2] for small antennas, i.e., with a diameter lower than 50 wavelengths, is introduced. It is a planar and a compact structure with a size of 40×40×2 cm. The antenna is formed by an array of 256 printed elements covering a large bandwidth (14.7%) at X-Band. The specification includes transmission (Tx) and reception (Rx) bands simultaneously. The printed antenna has a radiation pattern with a 3dB beamwidth of 5°, over a 31dBi gain, and a dual and an interchangeable circular polarization
Resumo:
An antenna which has been conceived as a portable system for satellite communications based on the recommendations ITU-R S.580-6 and ITU-R S.465-5 for small antennas, i.e., with a diameter lower than 50 wavelengths, is introduced. It is a planar and a compact structure with a size of 40×40×2 cm. The antenna is formed by an array of 256 printed elements covering a large bandwidth (14.7%) at X-Band with a VSWR of 1.4:1. The specification includes transmission (Tx) and reception (Rx) bands simultaneously. The printed antenna has a radiation pattern with a 3dB beamwidth of 5°, over a 31dBi gain, and a dual and an interchangeable circular polarization.