The redox behavior of CuZSM-5 was investigated by flow microbalance and FTIR measurements using CO and NO as probe molecules. The weight change resulting from switching the flow of 10% O2 in He to pure He corresponded to the removal of extralattice oxygen and approximately 20% autoreduction of total copper ion by one electron. FTIR absorption spectra of CO over CuZSM-5 showed that the concentration of the Cu+ sites changed reversibly upon switching the pretreatment gas from He to O2. The combined experiments (flow microbalance and CO adsorption) proved that CuZSM-5 has a redox function at 500 °C. Continuous measurement of NO adsorption spectra using the same wafer, following a pretreatment in flowing He at 500 °C, also demonstrated the redox properties of CuZSM-5. During the early stage of NO adsorption, a sharp band at 2295 cm-1 appeared that could be assigned in several different ways. Changes occurring as NO underwent reaction on the surface were recorded.

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Guided by a stress-buffering model, this study examined the effect of the caregiver stress on depressive symptoms, specifically the moderating effects of social support and volunteering on the relationship between stress and depressive symptoms among grandparent caregivers. The 2010 Health and Retirement Survey included a sample of 1,973 grandparent caregivers who reported their stress scores. Findings suggest that positive social support and volunteering significantly moderated the relationship between stress and depressive symptoms. In particular, the study revealed that perceived quality of relations may help grandparent caregivers cope with their ongoing stress and enlarged social interaction may buffer the increase of negative stressor outcomes.

Caring for an older adult with memory loss is stressful. Caregiver stress could produce negative outcomes such as depression. Previous research is limited in examining multiple intermediate pathways from caregiver stress to depressive symptoms. This study addresses this limitation by examining the role of self-efficacy, social support, and problem-solving in mediating the relationships between caregiver stressors and depressive symptoms. Using a sample of 91 family caregivers, we tested simultaneously multiple mediators between caregiver stressors and depression. Results indicate that self-efficacy mediated the pathway from daily hassles to depression. Findings point to the importance of improving self-efficacy in psychosocial interventions for caregivers of older adults with memory loss.

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