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Stress And Cognitive Performance In Older Adults, Christopher B. Rosnick

USF Tampa Graduate Theses and Dissertations

The current dissertation sought to examine stress in three different, but overlapping, ways. The first study examined how self-reported negative life events, in the aggregate and individually, are associated with cognitive performance. The results suggested that there was no significant relationship between the aggregate measures of self-reported negative life events and cognitive performance. On the other hand, several individual negative life events were associated with cognitive functioning. The findings support previous research indicating that using estimates of individual stressors rather than aggregate measures of stressors increases the predictive validity of stress measurement.

The second study assessed the cross-sectional and longitudinal …

Supercritical Carbon Dioxide Aided Preparation Of Nickel Oxide/Alumina Aerogel Catalyst, Haitao Li

USF Tampa Graduate Theses and Dissertations

The strength, thermal stability, pore structure and morphology are keys to success for wider deployment of aerogels. Furthermore, co or subsequent functionalization of the surfaces are equally, if not more important. This study addresses these issues through a new method. The path involves successful use of surfactant templating, supercritical extraction and drying, and supercritical fluid aided functionalization of the surface. Alumina support and alumina supported nickel catalyst particles are used to evaluate the approach. Initially thermally stable surfactant alumina was synthesized. The surfactant template was removed completely with the aid of a supercritical solvent mixture. Surfactant-templated alumina aerogel showed remarkable …

The Benefits Of Clear Speech At Normal Rates For Older Listeners With Normal Hearing, Athina Panagos Panagiotopoulos

USF Tampa Graduate Theses and Dissertations

Clear speech is a type of speaking style that improves speech intelligibility for many individuals. For example, one study showed a 17 percentage point increase in intelligibility over conversational speech for individuals with sensorineural hearing loss (Picheny et al., 1985). The clear speech benefit also extends to children with learning disabilities (Bradlow et al., 2003), non-native listeners (Bradlow & Bent, 2002), and other populations. Although clear speech is typically slower than conversational speech, it can be produced, naturally, at normal rates with training. For young listeners with normal hearing, clear speech at normal rates (clear/normal) is more intelligible than conversational …