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Nonviral gene delivery, though limited by inefficiency, has extensive utility in cell therapy, tissue engineering, and diagnostics. Substrate-mediated gene delivery (SMD) increases efficiency and allows transfection at a cell-biomaterial interface, by immobilizing and concentrating nucleic acid complexes on a surface. Efficient SMD generally requires substrates to be coated with serum or other protein coatings to mediate nucleic acid complex immobilization, as well as cell adhesion and growth; however, this strategy limits reproducibility and may be difficult to translate for clinical applications. As an alternative, we screened a chemically defined combinatorial library of 20 different extracellular matrix mimetic substrates containing combinations of (1) different sulfated polysaccharides that are essential extracellular matrix glycosaminoglycans (GAGs), with (2) mimetic peptides derived from adhesion proteins, growth factors, and cell-penetrating domains, for use as SMD coatings. We identified optimal substrates for DNA lipoplex and polyplex SMD transfection of fibroblasts and human mesenchymal stem cells. Optimal extracellular matrix mimetic substrates varied between cell type, donor source, and transfection reagent, but typically contained Heparin GAG and an adhesion peptide. Multiple substrates significantly increased transgene expression (i.e. 2- to 20-fold) over standard protein coatings. Considering previous research of similar ligands, we hypothesize extracellular matrix mimetic substrates modulate cell adhesion, proliferation, and survival, as well as plasmid internalization and trafficking. Our results demonstrate the utility of screening combinatorial extracellular matrix mimetic substrates for optimal SMD transfection towards application- and patient-specific technologies. IMPACT STATEMENT: Substrate-mediated gene delivery (SMD) approaches have potential for modification of cells in applications where a cell-material interface exists. Conventional SMD uses ill-defined serum or protein coatings to facilitate immobilization of nucleic acid complexes, cell attachment, and subsequent transfection, which limits reproducibility and clinical utility. As an alternative, we screened a defined library of extracellular matrix mimetic substrates containing combinations of different glycosaminoglycans and bioactive peptides to identify optimal substrates for SMD transfection of fibroblasts and human mesenchymal stem cells. This strategy could be utilized to develop substrates for specific SMD applications in which variability exists between different cell types and patient samples.

This thesis is about the optimization of the Mid-Columbia hydropower system, which is comprised of seven cascaded hydropower projects on the Columbia River. It is the largest system of its kind in the United States, and it possesses unique qualities that make it useful to power system operators and important for the integration of variable and intermittent wind and solar generation. This research formulates real-time and day-ahead optimization programs to plan cascade operations and coordinate hydro and wind resources. These programs are used to evaluate the potential benefits of real-time optimization (with and without wind firming) and hydro-wind coordination with day-ahead replanning and to estimate the battery-like properties of the Mid-Columbia system when it is used to balance wind variability. The system is simulated and tested using a multi-year wind and hydropower dataset that has been compiled from publicly available resources and estimated using bespoke software tools. Our results demonstrate that real-time optimization can increase hydraulic potential by 0.74 percent and stored energy by 0.68 percent. The power capacity of the Mid-Columbia hydropower battery is +/- 3000 and +/- 750 megawatts with and without replanning, respectively. Round-trip conversion efficiency exceeds 80 percent, and energy storage capacity is several tens of gigawatt-hours. These estimates may be too conservative or too optimistic depending on modeling assumptions, and they are subject to significant uncertainty. The primary factor inhibiting the performance of the hydropower battery was the maximum generation capacity of the hydropower system.