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Atom transfer radical polymerization (ATRP) has emerged as a robust tool to synthesize soft materials with defined structures for bioengineering and nanocomposites. In the past decade, numerous efforts were devoted to developing a novel polymerization method, electrochemically controlled radical polymerization (eATRP), which requiring less catalysts. However, due to restriction of special design, susceptible to oxygen and less control in aqueous buffers, challenges still remain. To address these difficulties, we hypothesized extracellular electron transfer from micro-oganisms could be utilized to control the performance of an exogenous oxidation-reduction (redox) reaction. We show that the electroactive bacterium Shewanella oneidensis can control the activity of a copper catalyst in ATRP. Precise control over the molecular weight and polydispersity of synthetic polymer could be achieved by mixing the bacterial suspension into the reaction medium. We also found that catalyst performance could be augmented by specific electron transport proteins and bacterial metabolism, offering potential targets for future applications. Performing ATRP under air is almost impossible because oxygen will quench the polymerization. We show that S. oneidensis can control metal-catalyzed living radical polymerizations under aerobic conditions by first consuming dissolved oxygen via aerobic respiration, then directing extracellular electron flux to the polymerization catalysts. In both open and closed containers, S. oneidensis enabled living radical polymerizations without requiring the pre-removal of oxygen. Polymerization activity was effective for wide ranges of monomers using low concentrations of biocompatible metal catalysts including Fe and Co. Moreover, polymerizations could be initiated using lyophilized or spent (recycled) cells. Finally, in order to understand the surface chemistry of metal organic frameworks (MOFs), we develop a surface functionalization method for water-stable MOFs by phage display. Specific frameworks binding peptides were identified, and their thermodynamic binding affinities and specificities were measured. Microscopy, X-ray diffraction, and gas adsorption analysis confirmed that the peptide functionalized frameworks retained similar characteristics. Microcopy imaging technique showed that peptide was localized on the surface of the frameworks, without blocking pore of MOFs. Last but not least, we measured the pH-dependent release of fluorescein from peptide-functionalized frameworks and discovered that peptide-binding can attenuate fluorescein release by improving framework stability under low pH conditions

Just as in most industrial countries, in Taiwan, women seem more likely than men to experience poorer health during their life course. In recent national surveys conducted in Taiwan, women consistently report poorer health than do men. Nevertheless, the risk factors and the mechanisms through which they operate to produce gender differences in health in Taiwan remain poorly understood. Evidence has suggested that gendered differences in health are a consequence of the stratification system. In current Taiwan society, women remain disadvantaged in terms of educational attainment, labor force participation, and division of domestic labor. Accordingly, while existing studies of gender differences in health in Taiwan focus on the comparisons of male and female health behaviors, this research highlights the important influence of education, employment, and family roles in shaping the gender gap in morbidity. Because many married women in Taiwan are informally employed in family firms, this research also pays attention to examining the impact of working in a family business on the health of married women. This project employs two data sets drawn from the Taiwan Social Change Survey in year 2000 and 2002. The effects of social factors on multiple health measures, including chronic disease status, illness status in the past two weeks, and self-rated health, are examined. Results indicate that gender differentials in health in different age groups are determined by different sets of social and behavioral factors. The impacts of combining paid work and family responsibilities on health vary depending on social and demographic variables such as gender, age, the type of employment, and the nature of family roles. Specifically, the findings reveal that the protective effect of familial employment is particularly significant among young married women. Finally, the effects of employment on health are found to be partly mediated through working hours.