Charge transfer excitons in optical absorption spectra of C60-dimers and polymers

Charge-transfer (CT) exciton effects are investigated for the optical absorption spectra of crosslinked C60 systems by using the intermediate exciton theory. We consider the C60-dimers, and the two (and three) molecule systems of the C60-polymers. We use a tight-binding model with long-range Coulomb interactions among electrons, and the model is treated by the Hartree-Fock approximation followed by the single-excitation configuration interaction method. We discuss the variations in the optical spectra by changing the conjugation parameter between molecules. We find that the total CT-component increases in smaller conjugations, and saturates at the intermediate conjugations. It decreases in the large conjugations. We also find that the CT-components of the doped systems are smaller than those of the neutral systems, indicating that the electron-hole distance becomes shorter in the doped C60-polymers.Comment: Figures should be requested to the autho

The meaning of actualization of self-care resources among a group of older home-dwelling people—A hermeneutic study

Self-care is an activity of mature persons who have developed their abilities to take care of themselves. Individuals can choose to actualize their self-care abilities into self-care activities to maintain, restore, or improve health and well-being. It is of importance to understand the meaning of the actualization of self-care resources among older people. The aim of this study was to investigate the meaning of the actualization of self-care resources, i.e., actions taken to improve, maintain, or restore health and well-being, among a group of older home-dwelling individuals with a high sense of coherence. The design of this study was to reanalyse narratives revealing self-care activities from 11 (five females and six males) Norwegian older home-dwelling people (65 years or older) identified as having a high sense of coherence. In order to reveal the meaning and get an understanding of why these self-care resources were realized or actualized, a Gadamerian-based research method was chosen. The analysis revealed four themes that showed the meaning of actualization of self-care resources in the study group: “Desire to carry on”, “Be of use to others”, “Self-realization”, and “Confidence to manage in the future”. The findings showed what older people found meaningful to strive for, and this information can be used as a guide for health professionals when supporting older people in their self-care. Older people with self-care resources can also be an important resource for others in need of social contact and practical help. These resources have to be asked for in voluntary work among older people in need of help and, thereby, can be a valuable supplement to the community health care system

Effects of smoking cessation on insulin and cardiovascular risk factors--a controlled study of 4 months' duration

OBJECTIVES: To investigate the effects on serum lipids, plasma fibrinogen, plasma insulin, plasma C-peptide and blood glucose, of smoking cessation after 4 months. To develop a group-based smoking intervention programme in primary health care. SETTING: Twenty health centres in primary health care in southern Sweden. SUBJECTS: Four hundred habitual smokers (> 10 cigarettes per day-1, > 10 years), recruited by advertisement in local papers. INTERVENTION: The smokers were randomized, after stratification for age and sex, to one intervention group (n = 200) and one control group (n = 200). The intervention group was offered supportive group sessions and free nicotine supplementation (patches, chewing gum). MAIN OUTCOME MEASURES: All participants were investigated at the start and after 4 months (medical history, physical examination, laboratory evaluation). Blood samples were drawn for determination of glucose, insulin and C-peptide, both in the fasting state and during an oral glucose tolerance test (OGTT), and for measurement of lipoproteins, fibrinogen, nicotine and cotinine. RESULTS: In the intervention group 98 of the subjects (48%) had quit smoking after 4 months. They were compared with the 156 subjects in the control group (91%) who were still daily smokers during the whole period. There were no significant differences in any variable between the two (total) experimental groups at baseline. Plasma nicotine and cotinine decreased (P < 0.001) in the intervention group following smoking cessation, and weight increased by 2.7 kg. In the intervention group HDL-cholesterol increased by 11% (P < 0.001), whereas HbA1c increased by 2% (P < 0.05) only in the control group. No changes occurred in levels of glucose, insulin, C-peptide and fibrinogen. CONCLUSION: The smoking cessation programme had a success rate of almost 50% over 4 months. Smoking cessation was associated with a marked increase in HDL-cholesterol levels but did not affect glucose tolerance. A concomitant weight increase may have blunted any independent beneficial effect of smoking cessation on glucose metabolism