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The objective of this study was to investigate the interaction between ethanol and dextroamphetamine with regard to psychomotor performance. Twelve healthy, male, paid volunteers, moderate users of ethanol and amphetamines, participated in this study. Ethanol (0.85 g/kg or placebo) was administered over a 30-min interval. Five minutes before the termination of ethanol or placebo ingestion, dextroamphetamine elixir (0.09 mg/kg, 0.18 mg/kg or placebo) diluted in 50 ml of orange juice was administered. Subjects were tested in a single-blind, latin-square, crossover design with each of the following six conditions: placebo ethanol/placebo dextroamphetamine; placebo ethanol/low-dose dextroamphetamine; placebo ethanol/high-dose dextroamphetamine; ethanol/placebo dextroamphetamine; ethanol/low-dose dextroamphetamine; and ethanol/high-dose dextroamphetamine. The variables measured in this study were: subjective rating of ethanol and dextroamphetamine intoxication, accuracy and latency of response in the Simulator Evaluation of Drug Impairment (SEDI task), blood ethanol concentration by breath analyzer, and plasma concentrations of dextroamphetamine by gas chromatography. Results indicate ethanol induced decrements in performance of the skills necessary to drive an automobile were significantly decreased by dextroamphetamine in a dose-response fashion. The administration of dextroamphetamine did not decrease the subjective ratings of ethanol intoxication.

We have measured the specific heat of multilayers of superconducting amorphous Mo77Ge23 layers separated by insulating amorphous germanium. We observe a fluctuation regime in quantitative agreement with predictions for two-dimensional superconductivity. The fluctuation peak is rapidly suppressed by the application of small magnetic fields perpendicular to the layers, and the transition becomes extremely broad as the field is increased. The transition widths scale as expected for a field-induced 2D to OD crossover, and are in excellent agreement with the exact result for OD fluctuations.

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We report linear electrical transport in perpendicular magnetic fields of very thin amorphous MoGe superconducting films and Mooe/Ge multilayers. These measurements avoid the inhuence of sample edges, which were sometimes dominant in earlier experiments. We demonstrate that the magnetic coupling in this system is not significant. Measurements of Josephson-coupled multilayers reveal the existence of a characteristic mass anisotropy that divides qualitatively different regimes of behavior. This characteristic anisotropy may be related to the strength of the random pinning in the system.Recently, numerous theoretical and experimental studies have investigated aspects of vortex motion in coupled type-II superconducting layers in the presence of thermal Quctuations, static diisorder (vortex pinning), and even quantum fluctuations. This work has derived largely