Planning across differences: collaborative planning processes for the California Central Valley's future

This dissertation examines the intersections between difference, participation, and planning processes. Rooted in scholarly conversations about deliberative democracy, collaborative planning, and nonprofit organizations in civil society, this research considers how planning practitioners can better plan across difference. Through case study research, this dissertation examines a collaborative planning process conducted by a nonprofit organization. Unlike more conventional participatory planning processes, the organization utilized scenario planning. Exercising their position in civil society, participation in the process was not open to all community members and the organization carefully selected a diverse set of participants. Findings from this research project indicate that this process, by moving away from a strict definition of rational discourse, focusing on multiple futures as opposed to a single, utopian future, and deliberately bringing together a broad cross-section of community members allowed for participants to speak freely and learn from one another’s perspectives and experiences. Experiences of process participants also demonstrate the degree to which cultural backgrounds shape participation in and expectations of planning processes. While there remains no clear answer in how to represent and respond to cultural differences in planning processes, the experiences of the organization, program staff, and community participants help scholars and practitioners move closer to planning across differences.

Single-molecule fluorescence resonance energy transfer study of SNARE-mediated membrane fusion

This is a comprehensive study of protein-mediated membrane fusion through single-molecule fluorescence resonance energy transfer (smFRET). Membrane fusion is one of the important cellular processes by which two initially distinct lipid bilayers merge their hydrophobic cores, resulting in one interconnected structure. For example, exocytosis, fertilization of an egg by a sperm and communication between neurons are a few among many processes that rely on some form of fusion. Proteins called soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) play a central role in fusion processes which is also regulated by many accessory proteins, such as synaptotagmin, complexin and Munc18. By a new lipid mixing method at the single-vesicle level, we are able to accurately detect different stages of SNARE-mediated membrane fusion including docking, hemi and full fusion via FRET value of single donor/acceptor vesicle pair. Through this single-vesicle lipid mixing assay, we discovered the vesicle aggregation induced by C2AB/Ca2+, the dual function of complexin, and the fusion promotion role of Munc18/SNARE-core binding mode. While this new method provides the information regarding the extent of the ensemble lipid mixing, the fusion pore opening between two vesicular cavities and the interaction between proteins cannot be detected. In order to overcome these limitations, we then developed a single-vesicle content mixing method to reveal the key factor of pore expansion by detecting the FRET change of dual-labeled DNA probes encapsulated in vesicles. Through our single-vesicle content mixing assay, we found the fusion pore expansion role of yeast SNAREs as well as neuronal SNAREs plus synaptotagmin 1.