940 resultados para Electrical-stimulation


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This study was carried out for recognized ichthyophon and investigation of feeding and effects of water temperature, salinity and electrical conductivity on the population dynamic of Barbus grypus in the Dalaki and Helle river. In the study period, 2949 Barbus grypus was cached. The most of total length frequency was 200 to 300 mm and 2 to 3 years old. The oldest fish was8 years old with 756 mm total length. Fecundity was 950 upto 57400 oocyt per fish. Station no. 6 and 7 showed more temperature, fecundity and GSI than other stations. Females adulated before then males. Multiple stepwise regression of fecundity and RE (reproduction effort) showed significant correlation. Fishes of the upper parts of stream was more L than down stream stations. Condition factor of males was more than female, and for down stream stations was better than the other stations. Barbus grypus is omnivorous. Ichthyophon of Dalaki river include 4 family and 9 species that Capoeta capoeta intermadia was more than others species, but in the Helle river was 5 family and 9 species, that Liza abu zarudni was more than others.

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The network oscillation and synaptic plasticity are known to be regulated by GABAergic inhibition, but how they are affected by changes in the GABA transporter activity remains unclear. Here we show that in the CA1 region of mouse hippocampus, pharmacolog

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In this paper, we present experimental results describing enhanced readout of the vibratory response of a doubly clamped zinc oxide (ZnO) nanowire employing a purely electrical actuation and detection scheme. The measured response suggests that the piezoelectric and semiconducting properties of ZnO effectively enhance the motional current for electromechanical transduction. For a doubly clamped ZnO nanowire resonator with radius ~10 nm and length ~1.91 µm, a resonant frequency around 21.4 MHz is observed with a quality factor (Q) of ~358 in vacuum. A comparison with the Q obtained in air (~242) shows that these nano-scale devices may be operated in fluid as viscous damping is less significant at these length scales. Additionally, the suspended nanowire bridges show field effect transistor (FET) characteristics when the underlying silicon substrate is used as a gate electrode or using a lithographically patterned in-plane gate electrode. Moreover, the Young's modulus of ZnO nanowires is extracted from a static bending test performed on a nanowire cantilever using an AFM and the value is compared to that obtained from resonant frequency measurements of electrically addressed clamped–clamped beam nanowire resonators.

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Very low doses (0.00001 mg/kg) of the alpha-2 adrenergic antagonist, yohimbine, improved working memory performance in a subset of aged monkeys. Improvement appeared to result from increased norepinephrine (NE) release onto postsynaptic alpha-2 adrenoceptors, as the response was blocked by the ''postsynaptic'' alpha-2 antagonist, SKF104078. Cognitive-enhancing effects of low dose yohimbine treatment may depend on aged animals retaining an intact, endogenous NE system. In contrast to yohimbine, the alpha-2 agonist, clonidine, has improved working memory in air aged animals examined. In the present study, clonidine's beneficial effects were also blocked by the postsynaptic antagonists SKF104078 and SKF104856, suggesting that clonidine acts by directly stimulating postsynaptic alpha-2 adrenoceptors. Beneficial doses of clonidine (0.01 mg/kg) and yohimbine (0.00001 mg/kg) were combined to see if they would produce additive effects on memory enhancement. This strategy was successful in young monkeys with intact NE systems but was not effective in the aged monkeys. These findings demonstrate that drugs that indirectly stimulate postsynaptic alpha-2 receptors by increasing NE release are not as reliable in aged monkeys as directly acting agonists that can replace NE at postsynaptic alpha-2 receptors.

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A superconducting fault current limiter (SFCL) in series with a downstream circuit breaker could provide a viable solution to controlling fault current levels in electrical distribution networks. In order to integrate the SFCL into power grids, we need a way to conveniently predict the performance of the SFCL in a given scenario. In this paper, short circuit analysis based on the electromagnetic transient program was used to investigate the operational behavior of the SFCL installed in an electrical distribution grid. System studies show that the SFCL can not only limit the fault current to an acceptable value, but also mitigate the voltage sag. The transient recovery voltage (TRV) could be remarkably damped and improved by the presence of the SFCL after the circuit breaker is opened to clear the fault. © 2007 British Crown Copyright.