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We report the results of the combined experimental and theoretical studies of the low-lying exciton states in crystalline copper phthalocyanine. We derive the eigen energy spectrum for the two lowest intramolecular Frenkel excitons coupled to the intermolecular charge transfer exciton state and compare it with temperature dependent optical absorption spectra measured experimentally, to obtain the parameters of the Frenkel-charge-transfer exciton intermixing. The two Frenkel exciton states are spaced apart by 0.26 eV, and the charge transfer exciton state is 50 meV above the lowest Frenkel exciton. Both Frenkel excitons are strongly mixed with the charge transfer exciton, showing the coupling constant 0.17 eV which agrees with earlier experimental measurements. These results can be used for the proper interpretation of the physical properties of crystalline phthalocyanines. [ABSTRACT FROM AUTHOR]

Aim: To examine heterogeneity in outcome at 12 months following 8 weeks of treatment for smoking cessation with bupropion sustained-release (SR) 150 or 300 mg/day combined with behavioural counselling.Design, Setting, Participants: Smokers were recruited from a large healthcare system and then randomized to receive either bupropion SR 150 mg/day (n = 763) or 300 mg/day (n = 761) taken for 8 weeks in combination with either proactive telephone counselling or a tailored mail approach.Measurements and Findings: A comprehensive set of relevant individual pretreatment and treatment characteristics was included in the analysis. Smoking outcome at 12 months was defined as point-prevalence of any regular self-reported smoking within the 7 days prior to follow-up contact. Classification and regression tree analysis identified subgroups that varied with respect to likelihood of being nonsmokers at 12 months. Seven subgroups were identified among those receiving bupropion SR 150 mg/day (proportion of nonsmokers at 12 months ranged from 13.7% to 43.5%) and eight subgroups among those receiving bupropion SR 300 mg/day (proportion of nonsmokers at 12 months ranged from 9.6% to 51.7%). In the 150-mg/day group, those with the lowest rate reported no previous quit attempt of 1 month or more in duration while those with the highest rate all reported previous quit attempts of 1 month or longer. In the 300 mg/day group, those with the lowest rate had very high levels of dependence while those with the highest rate were more highly educated and smoked at a lower level. Across all subgroups, cost per 12-month quitter ranged from a low of USD302 to a high of USD2,502.Conclusions: These results indicate the presence of a substantial amount of variation in outcome following treatment with both dosages of bupropion SR, with substantial cost consequences. Variation in outcome could be reduced by providing treatments tailored to subgroups of individuals who are at exceptionally high risk for smoking following a quit attempt. [ABSTRACT FROM AUTHOR]

Purpose: To describe change in Minnesota's QUITPLAN helpline operations following provision of nicotine replacement therapy (NRT) to multisession counseling enrollees.Methods: NRT access began September 2002. Call volume is reported from September 2001 to May 2003 (pre-NRT = 2734, post-NRT = 12,536). A survey administered at 2 weeks assesses self-reported connection to services (response rate 80%, n = 538/670, pre-NRT vs. 67%, n = 400/595, post-NRT, p < .001).Results: Provision of NRT was followed by an increase in call volume (439 +/- 229 calls/month January through May pre-NRT vs. 1292 +/- 308 calls/month January through May post-NRT, p = .001). Enrollment in multisession counseling increased (17.4% pre-NRT vs. 75.3% post-NRT, p < .001). Among survey respondents, connection to services was not changed (83.8% pre-NRT vs. 88.0% post-NRT, p = .072). At 2 weeks, more respondents who enrolled in multisession counseling reported having a follow-up call scheduled (43.9% pre-NRT vs. 64.1% post-NRT, p = .001).Conclusions: This is an observational study. Providing NRT as part of a statewide helpline may increase recruitment and encourage callers to enroll in multisession counseling. [ABSTRACT FROM AUTHOR]