The electron mechanics of induction acceleration

The radial and axial motions of electrons in the betatron are described by means of a potential function of forces. Previously reported conditions of equilibrium, stability and damping of oscillations are derived for the region of parabolic variation of the potential. Extension of the analysis to, non-parabolic regions gives an account of the injection in conventional instruments in better agreement with experiment, particularly in regard to higher voltages of injection.Space charge limitations are discussed with the help of the Laplacian of the potential of forces.By means of an additional radial electric field electrons can be introduced as in the magnetron, without any asymmetry inherent in the conventional betatron circumferential injector. The analysis of the conditions of equilibrium and stability, greatly facilitated in this case by the notion of potential, shows that no substantial improvement in space charge limitations can be expected and that the required variations between the flux linking the electron orbits and the magnetic and electric fields at the orbits are difficult to realize on account of their complexity and narrow tolerances. The X-ray output of a small experimental double yoke instrument was measured by a phototube multiplier viewing an irradiated fluorescent screen and gave evidence of multiple group electron capture.     

Differential contribution of personality to the explanation of variance in achievement in the first language and mathematics at high school level

This study assessed the differential contribution of personality to the explanation of variance in achievement in the mother tongue and mathematics at the high school level. The results indicated that personality, as measured by the HSPQ, aided the explication of variance in achievement in the mother tongue significantly, but had little influence on mathematics. Personality contributed as much to the explanation of variance in the mother tongue as did the composite cognitive variable. The influence of personality on achievement in mathematics was shown to be negligible. Some practical implications for the teaching of the first language are drawn.     

Self-regulation of timeout duration in the modification of disruptive classroom behavior

The effects of self-determination vs. teacher-determination of timeout duration on disruptive behavior were investigated in a group of 15 students in a special classroom who had learning disabilities and/or behavior problems. There were five phases to the study: In a repeated measures design each subject received timeout for 5 minutes, no timeout, 5 minutes timeout, selfdetermined timeout duration, and student = teacher-determined timeout duration. The overall effect of timeout was to reduce significantly the rate of disruptive behavior. The effects of various timeout conditions did not differ, indicating self-management of timeout duration was just as effective as when the teacher set the timeout duration.     

Response to Intervention in Middle Schools: Practices and Outcomes

Response to intervention (RTI) is advocated in elementary school as a system‐wide, multitiered model of academic and behavioral interventions. Middle schools have begun adopting RTI models based on these existing elementary models. This investigation into current middle school RTI practices describes technical aspects as well as some of cultural and contextual issues surrounding implementation. The study included multiple data collection procedures including surveys, discussion groups, phone interviews, and site visits. Although many schools reported substantial progress with implementation, they recognized rigorous implementation of RTI posed such on‐going challenges as changes in staffing, curricular realignments, very limited selections of screening and progress monitoring tools aligned with their curriculum, and scheduling of secondary and tertiary level interventions.     

Parenting the gifted adolescent

Parenting gifted adolescents requires democratic and androgynous parenting practices to provide the guidance that gifted students look for as they grow toward adulthood.