Estimating the performance of lithium beam measurements of current density and electron density in an H-mode pedestal.

The lithium beam is an effective diagnostic tool for investigation of stability and particle transport in the pedestal. It was used successfully to measure edge current density on DIII-D, achieving qualitative agreement with neoclassical models. Electron density profiles were also measured. Proposed upgrades will continue these measurements with higher reliability as well as explore edge current measurements using spectroscopy. The optics will be redesigned to optimize throughput and aperture broadening and to replace the photomultiplier tubes with avalanche photodiodes. The new system will yield detailed measurements of the pedestal, complementing existing diagnostics for investigating pedestal stability, edge localized mode cycle, and particle transport through the pedestal.

An integrated charge exchange recombination spectroscopy/beam emission spectroscopy diagnostic for Alcator C-Mod tokamak.

A novel integrated charge exchange recombination spectroscopy (CXRS)/beam emission spectroscopy (BES) system is proposed for C-Mod, in which both measurements are taken from a shared viewing geometry. The supplementary BES system serves to quantify local beam densities and supplants the common calculation of beam attenuation. The new system employs two optical viewing arrays, 20 poloidal and 22 toroidal channels. A dichroic filter splits the light between two spectrometers operating at different wavelengths for impurity ion and beam neutrals emission. In this arrangement, the impurity density is inferred from the electron density, measured BES and CXRS spectral radiances, and atomic emission rates.

Amperometric immunosensors based on protein A coupled polyaniline-perfluorosulfonated ionomer composite electrodes.

A very sensitive immunosensor based on polyaniline/ Nafion/protein A (PA/NF/PrA) composite electrodes has been developed for the amperometric immunoanalysis with urease-labeled immunoreagents. The use of urease conjugated goat anti-RIgG (GaRIgG-Ur) as the labeled antibody and urea as the substrate with an amperometric detection at -200 mV (vs Ag/AgCl) resulted in a dynamic range of 50-2000 ng mL-1 and a low detection limit of 10 ng/mL (64 pM) for the immunoanalysis of rabbit immunoglobulin G (RIgG). Because of the special affinity between protein A and RIgG, the PA/NF/PrA electrode can be regenerated repetitively by changing the pH of the buffer solutions. Characteristics of the PA/NF/PrA/RIgG immunosensor and optimal conditions for the competitive immunoanalysis of RIgG with FIA were studied.

Modification by ketamine on the neuromuscular actions of magnesium, vecuronium, pancuronium and alpha-bungarotoxin in the primate.

The neuromuscular effects of ketamine, at cumulative doses of 2.5 and 10 mg.kg-1 iv, were studied by electromyographically quantifying the thumb response evoked by ulnar nerve stimulation in 25 monkeys anaesthetized with pentobarbital-N2O-O2. Ketamine alone at these doses had no neuromuscular effects. When the EMG response was maintained at 50% of control by a continuous infusion of magnesium, vecuronium, or pancuronium, ketamine depressed the responses by an additional 13 +/- 3%, 34 +/- 7% and 32.5 +/- 3.3% (mean +/- SEM), respectively, at the highest dose, P less than 0.05. In contrast, ketamine had no effect on the neuromuscular block produced by incremental doses of alpha-bungarotoxin. These results indicate that ketamine does not act on the postjunctional acetylcholine receptor. It plays a secondary role in neuromuscular block, possibly by prejunctional or postjunctional effects independent of receptor occupation.