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The introduction of bioactive chemicals from pharmaceuticals and active ingredients in personal care products (hereafter ‘PPCPs’) may pose a threat to ecosystems and human health. With advances in monitoring and detection, Chinese scientists have established PPCPs as pervasive pollutants in water bodies. While the full effects of PPCPs are not yet fully understood, concern is growing about the implications of PPCPs in the environment. This research employed a combination of environmental, social, and economic data to better understand the ecological risks and policy options, as well as the general publics’ behavior, preferences and willingness to pay for measures aimed at preventing pollution by PPCPs in China. To achieve these aims, I conducted a structured review of the published scientific literature, took a series of qualitative interviews with Chinese scientists’ working in this field and finally collected original survey data from residents living in China. The first section of my thesis is based on the results from the structured review of the published scientific literature relating to PPCP pollution in China. This chapter provides the basis for understanding perceptions of risk among scientists and the public, and highlight what further research is needed. The second section describes the results from a series of semi-structured interviews with Chinese scientists and explores in depth their perspectives, opinions, and attitudes on current PPCP research and on future needs in the field. The third section is based on the analysis of results from a custom designed survey of Chinese residents. Results highlight that disposal of unwanted PPCPs in the trash is by far the most common disposal method and identifies significant heterogeneity in attitudes towards a proposed hypothetical disposal program. Finally the results from the contingent valuation experiment suggest a substantial willingness to pay for policy measures aimed at reducing PPCP pollution.

The dynamic structure of DNA in vivo is the key to answer how DNA manages to participate all cell activities while under so many structural constraints. We are thus interested in investigating how DNA methylation, one of the most common means of DNA regulation, changes the dynamic structure of DNA in nucleosome, a structural modification of DNA in all eukaryotes. The protein component of nucleosome was successfully made with a improved protocol. DNA methylation was performed with methytransferase SssI. A state-of-the-art method, combining 3D-RISM, ensemble optimization method, and cgDNA was implemented, and it has shown the best fit of B-form DNA SAXS data so far. With all of these components, an SAXS experiment on nucleosome with methylated DNA is possible, and the experiment data can be interpreted. The result on DNA modeling also hints on future directions for developing better energy model of DNA in solution.

This investigation deals with modeling and numerical approximation of thermocapillary and surfactant effects in long wavelength evolution of thin liquid layers. We consider several aspects including: model development, scaling and perturbation analysis, variational formulations, finite element approximation and solution strategies for these problems. Issues related to treating the fluid volume constraint within this variational finite element setting are also considered. A linear stability analysis of the nonlinear thermocapillary problem is developed and its implications are explored numerically over the related parameter space. In the inclined plane case for the thermocapillary problem, it is observed in the time dependent finite element solutions that a slight inclination of the system may give rise to premature onset of instability. We also extend the treatment of the physical problem to include an insoluble surfactant monolayer and develop a supporting perturbation analysis. The resulting more complex model involves coupling to an additional transport equation for surfactant concentration on the surface. We develop the variational formulation, finite element implementation and stability analysis of this coupled system. We characterize the stability behavior into four parametric regions based on linear stability analysis and verify the behavior using finite element approximation of time dependent solutions on one and two-dimensional spatial domains.