Competition between single and double electron transfer in collisions of doubly charged molecular pyrrole ions with neutral pyrrole molecules

Cross-sections have been determined for one- and two-electron transfer channels in the collisions of keV gas-phase doubly charged pyrrole ions with pyrrole molecules. Measured single and double electron transfer total cross-sections approximate 45 Å2 and 15 Å2, respectively. A combination of symmetric resonance charge exchange and multistate curve-crossing models has been invoked to describe these reactions

Doubly charged ion mass spectra of alkyl-substituted furans and pyrroles

Doubly charged ion mass spectra of alkyl-substituted furans and pyrroles were obtained using a double-focusing magnetic mass spectrometer operated at 3.2 kV accelerating voltage. Molecular ions were the dominant species found in doubly charged spectra of lower molecular weight heterocydic compounds, whereas the spectra of the higher weight homologues were typified by abundant fragment ions from extensive decomposition. Measured doubly charged ionization and appearance energies ranged from 22.8 to 47.9 eV. Ionization energies were correlated with values calculated using self-consistent field–molecular orbital techniques. A multichannel diabatic curve-crossing model was developed to investigate the fundamental organic ion reactions responsible for development of doubly charged ion mass spectra. Probabilities for Landau–Zener type transitions between reactant and product curves were determined and used in the collision model to predict charge-transfer cross-sections, which compared favorably with experimental cross-sections obtained using time-of-flight techniques

Development and evaluation of a risk communication curriculum for medical students

Item does not contain fulltextOBJECTIVE: To develop, pilot, and evaluate a curriculum for teaching clinical risk communication skills to medical students. METHODS: A new experience-based curriculum, "Risk Talk," was developed and piloted over a 1-year period among students at Tufts University School of Medicine. An experimental study of 2nd-year students exposed vs. unexposed to the curriculum was conducted to evaluate the curriculum's efficacy. Primary outcome measures were students' objective (observed) and subjective (self-reported) risk communication competence; the latter was assessed using an Observed Structured Clinical Examination (OSCE) employing new measures. RESULTS: Twenty-eight 2nd-year students completed the curriculum, and exhibited significantly greater (p<.001) objective and subjective risk communication competence than a convenience sample of 24 unexposed students. New observational measures of objective competence in risk communication showed promising evidence of reliability and validity. The curriculum was resource-intensive. CONCLUSION: The new experience-based clinical risk communication curriculum was efficacious, although resource-intensive. More work is needed to develop the feasibility of curriculum delivery, and to improve the measurement of competence in clinical risk communication. PRACTICE IMPLICATIONS: Risk communication is an important advanced communication skill, and the Risk Talk curriculum provides a model educational intervention and new assessment tools to guide future efforts to teach and evaluate this skill