The operant behavior method has been utilized to ascertain whether certain drugs have the power to reinforce the animal's operant behavior and also whether the animal can self-administer the drug by means of automatic intravenous or intragastric injections (1-5).Using operant behavior the oral self-administration of morphine has been little studied though the preference for morphine has been reported (6-8). In our present work, the operant discrimination behavior was used with the drug-admixed food method (9, 10) to examine the oral self-administration of morphine.A Skinner discrimination box (25 x 20 x 30 cm) was used; two sets of levers, food trays and small lights were attached to the inside of the box. Two food dispensers outside the box were connected to the food trays by tubes (developed by our department and Charles River Japan, Inc., Kanagawa). Ordinary pellet food, weighing approx. 45 mg, was from the CLEA Japan, Inc. and the same type of pellet food which was produced by mixing morphine hydrochloride (1 mg/g food) into normal food was prepared in our department

Fig. 1 Schematic diagram of apparatus used to assess the degree of preference for a drug , by rats. The distance between the food cups is 30 cm.The diameter of each pulley is 10cm and 2.5cm.The weight connected to a cord indicates the degree of willingness to pull, by a rat, who wants the morphine-admixed food. Fig. 2 Pulling pattern of weight (40g/100g body weight) in the rat with a developed preference for morphine. The ordinate denotes the pulling distance (cm); and the abscissa, time.Fluctuating wave represents eating behavior of morphine-admixed food. Upper columns show the result of the control group and the lower ones the morphine group. Fig. 6 Pulling pattern of weights (40g/l00g body weight and 60g/l00g body weight) in the rats in the morphine (L) group. The ordinate denotes the pulling distance (cm); and the abscissa, time. Fluctuating wave represents eating behavior of morphine-admixed food. Psychol. 41, 450 (1948) Abstract-Tsutomu SUZUKI,

No abstract

No abstract

Body‐wave reflections are sensitive to sharp velocity contrasts, making them useful for lithological imaging. We analysed seismic data from natural earthquake, ambient noise and mine blasts to map P‐wave reflection profiles at the Hishikari mine area by autocorrelation analysis. Because fissure‐filled gold veins are dominant in this area, we evaluated the potential of autocorrelation analysis for investigating the shallow subsurface, including the ore deposits. Seismic interferometry is commonly performed based on the autocorrelation of ambient noise or natural earthquake signals; here, we instead used blasting in the mine because blast events include high‐frequency signals that boost the spatial resolution of the imaging. To effectively extract P‐wave reflections from seismic signals including blast events, we applied Gaussian smoothing and spectral whitening to remove source effects and then investigated the optimum frequency band. We successfully obtained auto‐correlograms showing high‐resolution seismic reflectors at shallow formation depths. These reflections are interpreted to be lithological boundaries shallower than 500 m. A comparison with profiles obtained from ambient noise and earthquake data showed that blasting signals yielded highly spatially consistent reflections that would not be achievable with natural or ambient seismic sources. This study highlights the potential of using blast autocorrelation seismic analysis during short survey periods. By using single‐blast shots and dense seismic station spacings, we successfully achieved higher resolution 3D reflection images of lithological interfaces, possibly including ore veins.