Beads on a vibrating wire are used to simulate the discrete structure of a solid-state material. The novel idea of the experiment is to use very small oscillation amplitudes of the wire to avoid nonlinearities in the interaction. We achieve a good signal-to-noise ratio using a lock-in technique. We find quantitative agreement between theory and experiment for not only a mono-and a diatomic chain, but also for the bare wire. The latter agreement is the crucial aspect that distinguishes our experiment from previous ones. This agreement assures that the fundamental assumption of the theory ͑Hooke's law͒ is satisfied. We show that the properties of phonon dispersion curves are not special, and that the same band structures occur when the wavelength of any wave becomes comparable to the length scale of a discrete periodicity.

The purpose of this study was to evaluate the effects of self-recording and contingent reinforcement on exercise participation by four adults with acquired brain injury. The results indicate that self-recording and contingent reinforcement increased participation in stretching, aerobic, and weight-lifting activities for each participant. The results also indicate that each participant was able to accurately self-record his or her exercise participation. Possible operant conceptualizations for the observed behavior change, as well as limitations to the results, are briefly discussed.

This study implemented a modified teaching interaction procedure to teach social skills to 4 children diagnosed with autism spectrum disorder with an intellectual disability. A multiple baseline design across social skills and replicated across participants was utilized to evaluate the effects of the modified teaching interaction procedure. The results demonstrated that the teaching interaction procedure resulted in all participants acquiring targeted social skills, maintaining the targeted social skills, and generalizing the targeted social skills.

This article describes applications of videodisc technology to instruction. The focus is on the incorporation of videodiscs into methods training for preservice teachers. Methods training requires that teacher trainees acquire a knowledge base for instructional skills, learn to identify specific instructional methods, and learn to discriminate between appropriate and inappropriate applications of particular methods. Next, trainees must learn to perform each method and, finally, must apply each method in the classroom. Videodiscs are an efficient medium for teaching about teaching methods. However, the videodisc cannot provide practice in the actual performance of teaching skills, and must be supplemented with live supervision. In combination with other instructional technologies, it provides an efficient medium for helping preservice teachers to learn instructional methods.