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We have measured the reaction rates of trapped, buffer gas cooled Th$^{3+}$ and various gases and have analyzed the reaction products using trapped ion mass spectrometry techniques. Ion trap lifetimes are usually limited by reactions with background molecules, and the high electron affinity of multiply charged ions such as Th$^{3+}$ make them more prone to loss. Our results show that reactions of Th$^{3+}$ with carbon dioxide, methane, and oxygen all occur near the classical Langevin rate, while reaction rates with argon, hydrogen, and nitrogen are orders of magnitude lower. Reactions of Th$^{3+}$ with oxygen and methane proceed primarily via charge exchange, while simultaneous charge exchange and chemical reaction occurs between Th$^{3+}$ and carbon dioxide. Loss rates of Th$^{3+}$ in helium are consistent with reaction with impurities in the gas. Reaction rates of Th$^{3+}$ with nitrogen and argon depend on the internal electronic configuration of the Th$^{3+}$., Comment: 9 pages, 10 figures, 4 tables. Submitted to PRA

Simple and effective techniques for loading barium ions into linear Paul traps are demonstrated. Two-step photoionization of neutral barium is achieved using a weak intercombination line (6s2 1S0 <-> 6s6p 3P1, 791 nm) followed by excitation above the ionization threshold using a nitrogen gas laser (337 nm). Isotopic selectivity is achieved by using a near Doppler-free geometry for excitation of the triplet 6s6p 3P1 state. Additionally, we report a particularly simple and efficient trap loading technique that employs an in-expensive UV epoxy curing lamp to generate photoelectrons., Comment: 5 pages, Accepted to PRA 3/20/2007 -fixed typo -clarified figure 3 caption -added reference [15]

To assess the quality of local news programs, a News Quality Index was develped for a study that consisted of three parts: a content analysis of local television news, an audience analysis of the kinds of news stories that are most important, and an outside the market viewer analysis of the way in which anchors for news, sports, and weather are perceived. A recording was made during the week of May 24-28, 1982 of the half-hour, early evening newscasts of the three network affiliates in the Mobile, Alabama-Pensacola, Florida market. One videotape for each station, with three minutes of news anchor reporting followed by three minutes of sports anchor reporting and three minutes of weather reporting, were presented to 37 students from a vocational school and community college outside the Mobile-Pensacola viewing area. Results showed that only one measure, the average number of minutes of commercials, revealed significant differences across stations. Concerning the technical quality of the newscast, analysis showed that the station that scored highest in the rankings contained more techniques per video tape recordings, more slides and stills accompanying the news anchor reporting, and a greater amount of video accompanying the sports reporter. Audience preferences revealed almost no relationship or a negative one between audience ratings of the relative importance of different kinds of news stories and the station's attention to these stories. Four categories were ranked as important in determining news quality, in the following order: news substance, technical quality, the association between public preference for news stories and the amount of time stations devoted to them, and the ratings of news, sports, and weather anchors. (HOD)

A study was conducted to explore the hypothesis that heavy television viewing, particularly the viewing of a great deal of violence, cultivates certain misconceptions about social reality. Four counties in Florida were selected for the study on the basis of geographical location and amount of violent crime. Survey questionnaires were administered to 524 adolescents in their classrooms in May 1984, and to 507 adults via telephone interviews during the summer of 1984. The findings for the adolescent sample provided only scant evidence that television might alter perceptions of social reality in a way that is consistent with its content. However, adults who watch a great deal of television or regularly view programs containing a great deal of violence expressed a heightened sense of danger and selfishness. Even when such factors as education and income are taken into account, the relationship between television viewing or the viewing of violence programs and fear of violence remains significant. Further research should seek to determine more precisely the processes by which cultivation takes place or by which psychological and sociological factors affect both television viewing and perceptions of reality. (DF)

The vocational education teacher was the focus of this study designed to gain a better understanding of how communication relates to teaching effectiveness in a vocational setting. Teaching effectiveness was defined in terms of four criteria: supervisor evaluations of teachers, student evaluations of teachers, absentee rate, and drop rate. The teachers who served as subjects for the study came from a number of industrial education programs located in Florida secondary schools, vocational-technical centers, and community colleges. Two trained observers spent two days with each teacher recording his behavior and the behavior of his students. Underscoring the importance of communication skills, this study showed that there were identifiable differences in behavior among teachers categorized according to supervisor and/or student ratings. The "best" teachers were very dynamic, had superior delivery skills, spent a great amount of time in direct contact with their students, and created a pleasant social-emotional environment through the use of positive reinforcement and banter. Seven recommendations were made for vocational education on the basis of the findings in this study. (Author/RB)

With the appearance of general off-the-shelf software packages for the simulation of mechanical systems, modelling and simulation of mechanisms has become an easier task. The authors have recently used one such package, DADS, to model the dynamics of rigid and flexible-link robotic manipulators. In this paper, we present this overview of our learning experiences with DADS, in the hope that it will shorten the learning process for others interested in this software.