34 research outputs found

    Effective nonlinear optical properties of composite media of graded spherical particles

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    We have developed a nonlinear differential effective dipole approximation (NDEDA), in an attempt to investigate the effective linear and third-order nonlinear susceptibility of composite media in which graded spherical inclusions with weak nonlinearity are randomly embedded in a linear host medium. Alternatively, based on a first-principles approach, we derived exactly the linear local field inside the graded particles having power-law dielectric gradation profiles. As a result, we obtain also the effective linear dielectric constant and third-order nonlinear susceptibility. Excellent agreement between the two methods is numerically demonstrated. As an application, we apply the NDEDA to investigate the surface plasma resonant effect on the optical absorption, optical nonlinearity enhancement, and figure of merit of metal-dielectric composites. It is found that the presence of gradation in metal particles yields a broad resonant band in the optical region, and further enhances the figure of merit.Comment: 20 pages, 5 figure

    Strategies to improve research capacity across European general practice

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    The effectiveness of any national healthcare system is highly correlated with the strength of primary care within that system. A strong research basis is essential for a firm and vibrant primary care system. General practitioners (GPs) are at the centre of most primary care systems.To inform on actions required to increase research capacity in general practice, particularly in low capacity countries, we collected information from the members of the European General Practice Research Network (EGPRN) and the European World Organization of Family Doctors (Wonca).A qualitative design including eight semi-structured interviews and two discursive workshops were undertaken with members of EGPRN and Wonca Europe. Appreciative inquiry methods were utilized. Krueger's (1994) framework analysis approach was used to analyse the data.Research performance in general practice requires improvements in the following areas: visibility of research; knowledge acquisition; mentoring and exchange; networking and research networks; collaboration with industry, authorities and other stakeholders. Research capacity building (RCB) strategies need to be both flexible and financially supported. Leadership and collaboration are crucial.Members of the GP research community see the clear need for both national and international primary care research networks to facilitate appropriate RCB interventions. These interventions should be multifaceted, responding to needs at different levels and tailored to the context where they are to be implemented

    Validation of the adherence evaluation of osteoporosis treatment (ADEOS) questionnaire for osteoporotic post-menopausal women

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    SUMMARY: We developed and validated a specific 12-item questionnaire to evaluate adherence to oral antiresorptive medication by post-menopausal osteoporotic women in everyday practice. Over the following 9 months, an index of ≤16 was associated with an increase in the risk of treatment discontinuation of 1.69 and of 2.10 for new patients who had started treatment within the previous year. INTRODUCTION: Adherence to medication in osteoporosis is poor. The goal of this study was to develop and validate a disease-specific questionnaire to evaluate adherence to treatment of women with post-menopausal osteoporosis taking oral antiresorptive medication. METHODS: A prototype adherence questionnaire with 45 items developed from patient interview, literature review, and physician opinion was evaluated in a sample of 350 post-menopausal women with osteoporosis treated in primary care. Item responses were matched against scores on the Morisky Medication Adherence Scale (MMAS). The most discriminant items were retained in the final questionnaire. Concurrent and predictive validity were assessed. RESULTS: Twelve items were associated with MMAS score at a probability level of 0.05. These were retained in the final questionnaire which provided an adherence index ranging from 0 to 22. An index of ≥20 was associated with a high probability of persistence and an index ≤ 16 with a high probability of treatment discontinuation in the following 9 months. CONCLUSIONS: The ADEOS-12 is a simple patient-reported measure to determine adherence to osteoporosis treatments with good concurrent and discriminant validity. This is the first disease-specific adherence measure to have been developed for osteoporosis

    Specialized inpatient treatment of adult anorexia nervosa: effectiveness and clinical significance of changes

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    Background: Previous studies have predominantly evaluated the effectiveness of inpatient treatment for anorexia nervosa at the group level. The aim of this study was to evaluate treatment outcomes at an individual level based on the clinical significance of improvement. Patients' treatment outcomes were classified into four groups: deteriorated, unchanged, reliably improved and clinically significantly improved. Furthermore, the study set out to explore predictors of clinically significant changes in eating disorder psychopathology. Methods: A total of 435 inpatients were assessed at admission and at discharge on the following measures: body-mass-index, eating disorder symptoms, general psychopathology, depression and motivation for change. Results: 20.0-32.0% of patients showed reliable changes and 34.1-55.3% showed clinically significant changes in the various outcome measures. Between 23.0% and 34.5% remained unchanged and between 1.7% and 3.0% deteriorated. Motivation for change and depressive symptoms were identified as positive predictors of clinically significant changes in eating disorder psychopathology, whereas body dissatisfaction, impulse regulation, social insecurity and education were negative predictors. Conclusions: Despite high rates of reliable and clinically significant changes following intensive inpatient treatment, about one third of anorexia nervosa patients showed no significant response to treatment. Future studies should focus on the identification of non-responders as well as on the development of treatment strategies for these patients

    A pragmatic trial of acamprosate in the treatment of alcohol dependence in primary care.

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    To assess the effectiveness of pharmacotherapy with acamprosate in alcohol-dependent patients treated in a naturalistic setting in primary care in France. 422 patients were included. At the end of the study, patients randomized to the acamprosate group had significantly better outcomes in terms of total ARPQ score, change from baseline (–2.61 vs –3.44) and number of subjects with no alcohol-related problem. On average, patients treated with acamprosate had one less alcohol-related problem than did the controls. The number needed to treat in order to save one additional patient from alcohol-related problems compared to standard care was 7.14. Statistically significant differences in favour of the acamprosate group were observed for all secondary efficacy outcome measures including quality of life. Adjunctive therapy with acamprosate in primary care is associated with significantly better functional outcome. Pragmatic trials in alcohol dependence are both feasible and informative.Test de l'efficacité de l'acamprosate en tant que traitement d'apport et de soutien de l'abstinence alcoolique. les valeurs du critères principal (ARPQ) furent significativement inferieures dans le groupe traité. On estime le nombre necessaire à traiter à 7.14. Le traitement étudié est considéré augmenter l'efficience du suivi des patients tant en qualité de vie qu'en consequences sociales
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