Fe-substituted mullite powders for the in situ synthesis of carbon nanotubes by catalytic chemical vapor deposition

Powders of iron-substituted mullite were prepared by combustion and further calcination in air at different temperatures. A detailed study involving notably Mo¨ssbauer spectroscopy showed that the Fe3+ ions are distributed between the mullite phase and a corundum phase that progressively dissolves into mullite upon the increase in calcination temperature. Carbon nanotube-Fe-mullite nanocomposites were prepared for the first time by a direct method involving a reduction of these powders in H2-CH4 and without any mechanical mixing step. The carbon nanotubes formed by the catalytic decomposition of CH4 on the smallest metal particles are mostly double-walled and multiwalled, although some carbon nanofibers are also observed

Labor market reform and rent-sharing : a quasi-experiment experience

We analyze the impact on wages of the adoption of a rent-sharing remuneration scheme aiming at making labor institutions more flexible. We are working with a quasi- experimental setting referring to a sample of Italian companies before and after the introduction of the Treu Reform (1997). Our estimations confirm that this reform not only increased insider workers' wages via rent-sharing, but also fueled a s-convergence process of the rent-sharing elasticity across the sectors at a different rate. Finally, we deliver a reasoned discussion of the consequences at large of the implementation of this reform in the Italian job market

Symptoms of common mental disorders and their correlates among women in Accra, Ghana: a population-based survey

Introduction: To comply with its new mental health bill, Ghana needs to integrate mental health within other health and social services. Mental disorders represent 9% of disease burden in Ghana. Women are more affected by common mental disorders, and are underrepresented in treatment settings. This study examines physical and social correlates of mental illness in adult women in Accra, Ghana, so as to inform general clinical practice and health policy.Methods: The SF-36 and K6 forms and 4 psychosis questions were administered in three languages to 2,814 adult women living in Accra, as part of a larger cross-sectional population-based survey of women’s health. The validity of these tools was assessed through correlations within and between measures. Risk factors for mental distress were analysed using multivariate regression. Health service use was also described using statistical frequencies.Results: Both the SF36 and K6 appear valid in a female Ghanaian population. Low levels of education, poverty and unemployment are negatively associated with mental health. Physical ill health is also associated with mental distress. No association was found between mental distress and religion or ethnicity. Some additional risk factors were significant for one, but not both of the outcome variables. Only 0.4% of women reported seeing a mental health professional in the previous year, whereas 58.6% had visited a health centre.Conclusion: The implications for women are that marriage is neither good nor bad for mental health, but education and employment are strong protective factors. Researchers should note that the SF36 and K6 can be used in a Ghanaian population, however more research is needed to determine the cut-off point for serious mental illness on the K6, as well as research into mental disorders in a mixed-gender population

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