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Titanium and carbon elemental powder mixtures with compositions of Ti100-xCx (x=50,40,30) were milled under a helium atmosphere using a magnetoball mill. For Ti50C50 and Ti60C40 powder mixtures, the combined results of external mill temperature monitoring and x-ray diffraction (XRD) analysis indicated that, after a specific incubation period, titanium carbide (TiC) was formed rapidly via a highly exothermic mechanically induced reaction. However, contrary to the current understanding of mechanically induced self-propagating reactions, Raman spectroscopy clearly showed the formation of nonstoichiometric TiC in Ti50C50 and Ti60C40 powders prior to the sudden exothermic event occurring inside the mill. This result has not been reported in previous studies that used only XRD analysis to characterize the as-milled powders. It is now thought that a significant component of the heat generated after the incubation period may be due to a combination of rapid grain growth and/or recrystallization of the preexisting TiC, rather than the direct formation of TiC. When milling Ti70C30, the reaction to form TiC proceeded gradually as milling progressed. [ABSTRACT FROM AUTHOR]

Diets high in fruits and vegetables have been shown to decrease the risk of developing chronic diseases, yet BRFSS data show that only 21.8% of 18 to 24 year olds consume 5 or more fruits and vegetables per day. Increasing intakes of fruit and vegetables among young adults can improve public health as habits formed during this age period will also be passed on to the next generation. The Transtheoretical model (TTM or Stages of Change) posits that individuals make behavioral improvements by progressing through a series of stages. Behavior change models such as the TTM have enabled educators to enhance recruitment and retention and improve dietary behaviors. With Internet use growing at a rate of 20% per year, adaptation of stage-based educational materials to an interactive Web-based intervention provides a cost-effective strategy to promote change among large segments of the population. Mounting evidence demonstrates that computer-tailored nutrition education outperforms standard intervention methods as it is more likely to be read, recalled, discussed with others, and viewed as personally relevant. Our research team converted print-based educational messages to a Web-based format with interactive quizzes, individualized feedback, recipes, stage-appropriate video vignettes, and informational links. A pilot study examining the site's technical feasibility, acceptance by the target audience, and effectiveness (measured as a shift in stage of change, self-efficacy, decisional balance, and processes) is currently in progress. This study was supported by USDA/CSREES research grants and by the UW-Madison Interdepartmental Graduate Program in Nutritional Sciences.

Although telephone surveys are a common research tool, the use of telephone calls to distribute and reinforce educational material via telephone has not been widely adopted. Extension paraprofessionals (n = 39) conducted follow-up educational telephone calls as part of a 10-state intervention study that used the Transtheoretical Model for tailoring mailed materials for low-income young adults to increase fruit and vegetable intake. This study evaluated the paraprofessionals' perceptions of effectiveness and the adequacy of training using a Web-based survey (n = 21 of 29 located by e-mail) and in-depth telephone interviews with one paraprofessional from each state. Results from the Web-based survey showed that 86% of the respondents agreed that the telephone calls were somewhat to very practical. Participants reported in the in-depth interviews that the Stages of Change Model was very useful and well liked in providing personalized educational interventions. Similar results from the Web-based survey and in-depth interviews indicated that training to use the Stages of Change materials was adequate. Educators with a more positive perception of adequacy of training were more likely to follow the protocol for completing and reporting telephone calls (y = 1.0, P < .0001). Information from in-depth interviews revealed that 8 educators considered role playing using the Stages of Change scripts the most useful component of their training for making the telephone calls. This evaluation demonstrates the acceptability of using the Stages of Change Model for educational telephone calls by Extension paraprofessionals and should be considered a useful tool for future educational interventions with young adults.

Problem-based learning (PBL) for graduate-level clinical nutrition education was examined over 7 separate semesters with a test of knowledge, measures of self-perceived clinical competence, learning strategies, cognitive behaviors (eg, use of memorization, reflection), attitude toward problem content and format, and time requirements. Mean examination scores increased significantly by 10%, and self-perceived expertise was related to realized knowledge gains. Cognitive behavior changes supported association between PBL and preferred learning skills, thereby facilitating critical thinking. Problem development and curriculum processes are described. Findings endorsed an expeditious transition to a PBL-dominant, graduate-level clinical nutrition course, prior to a supervised practice program. [ABSTRACT FROM AUTHOR]