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Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

The purpose of this work was to investigate the effects of structure, humidity and aging on the mechanical behavior of Nafion® and Dais® ionomers. It was determined that the majority of the properties of these membranes were controlled by the formation and growth of the ionic clusters that were the direct result of the ionic nature of these materials. In the process of this study, the properties of Nafion® and sulfonated Dais® polymers were investigated by dynamic mechanical analysis and thermal gravimetric analysis and their water uptake and sorption and desorption isotherms were measured. A mastercurve and a shift factor plot were constructed for 60% sulfonated Dais® membrane. It was determined that an increase in the degree of sulfonation raised the glass transition temperature of these materials by facilitating the formation of the ionic clusters which acted as physical crosslinks, thereby reducing the mobility of polymeric chains. Water was found to effectively plasticize the membranes, especially in the case of Dais® materials, by reducing the storage modulus and decreasing the structural integrity of the ionomers. The effect of pre-treatment of Nafion® was investigated and the glass transition temperature was found to increase as a function of the severity of the treatment procedure. The maximum water uptakes were determined for virgin and aged Nafion® and Dais® membranes and their vapor phase water sorption diffusion coefficients were calculated. The sorption process was found to follow pseudo-Fickian behavior, while the movement of water out of the membranes during the desorption process was determined to be controlled by mechanisms other than diffusion. Lastly, the effect of exposure of Nafion® and 30% sulfonated Dais® membranes to the saturated environment at elevated temperatures was investigated and found to result in the increase in the glass transition temperature of the materials. Results of the exposure effects on the diffusion properties of Nafion® and Dais® were inconclusive. Preliminary findings attributed the changes in the properties of the materials to the counteractive actions of physical aging and the growth of the ionic clusters. / Master of Science

Traditional Birth Attendants (TBAs) are the primary health care providers for women at the time of childbirth in many parts of the world. In India, particularly in remote areas such as Garhwal, these women play a key role in maternal health. Training programmes for TBAs can lead to dramatic reductions in neonatal mortality as well as in maternal morbidity and mortality, due to improved hygienic practices at the time of delivery. Yet training programmes for TBAs often lack sociocultural relevance, and fail to incorporate an understanding of the TBAs' perceptions of the process of pregnancy and delivery. Understanding more about the role of the TBA as a diagnostician and a decision-maker within a given sociocultural context can make such training programmes more culturally congruent. This research report describes the way in which TBAs (dais) in Garhwal interpret obstetrical complications, and how they make decisions regarding the need for cosmopolitan medical care. TBAs in Garhwal interpret obstetrical complications using a variety of explanatory models, arising from an understanding of health and illness which shows influences of Vedic, Ayurvedic, folk and cosmopolitan medical models. These explanatory models often led to a perception of "danger” and the "dangerous case" which is widely divergent from the cosmopolitan medical model. Specific areas are identified where the dais' interpretation of "danger" was particularly divergent from the cosmopolitan medical model. These areas of conceptual conflict result in diagnoses and treatment procedures which can lead to significant delays in the woman receiving needed cosmopolitan medical care. The third stage of action-research process is the development of a participatory training programme, in which the TBA is an active participant. The aim of the training programme is to move towards a shared perception of risk regarding major obstetrical complications. / Thesis / Master of Arts (MA)