Thesis (Ph. D.)--University of California, San Diego, 2000. / Vita and abstract. Includes bibliographical references (leaves 499-519).

Thesis (M.A.)--Brigham Young University, Dept. of History.

Thesis (M.S.)--Oregon State University, 1996. / Typescript (photocopy). Includes bibliographical references (leaves 141-145). Also available on the World Wide Web.

Thesis (M.A.)--Brigham Young University, Dept. of History. / Electronic thesis. Also available in print ed.

No description available.

Actin polymerization facilitated by the Arp2/3 complex plays a critical role in a wide range of cellular processes such as motility, endocytosis and cargo recycling. Activation and appropriate localization of the Arp2/3 complex is mediated by an interaction with the nucleation-promoting factor (NPF). WASH complex is the major endosomal NPF which plays a crucial role in the cargo recycling back to the trans-Golgi network (TGN) or plasma membrane. It is composed of five subunits: WASH1, SWIP, FAM21, CCDC53 and strumpellin. While WASH1 and FAM21 have been extensively studied, much less is known about strumpellin, a protein causally implicated in the onset of hereditary spastic paraplegia (HSP). This work focuses on strumpellin function in the cells, showing that only full-length protein incorporates into the WASH complex. In a strumpellin knock out cell line, we demonstrated that loss of strumpellin resulted in destabilization of the other WASH complex subunits. Still, an incomplete WASH complex without strumpellin was assembled. Cells also displayed enlarged endosomal subdomains and WASH complex nucleation activity on endosomes was largely diminished as assessed by loss of the actin patches. Finally, the absence of strumpellin was also accompanied by the accumulation of glucose transporter 1 (GLUT1)...

Tunnels have become increasingly important in the development of road networks to meet rising transportation demands. Washing of road tunnels must be performed regularly to ensure traffic safety. The washing procedure generates significant amount of polluted wash water. Before discharge to a receiving water body, treatment is necessary to avoid potential degradation of the water quality. In this study, 12 in situ sedimentation experiments were conducted to evaluate treatment efficiency of sedimentation, with and without the addition of chemical flocculent. The findings showed that untreated tunnel wash water was highly polluted with total suspended solids (804-9690 mg/l), PAHs (0.4–29 μg/l) and heavy metals. Most pollutants were associated with the particulate material. Significant correlations (r2 > 0.95) were found between suspended solids and metals. Efficient removal of pollutants was possible by sedimentation with addition of flocculent. Within 20 hours of sedimentation low concentrations were reached of suspended solids (<15mg/l), PAHs (<0.1 μg/l), Cd (<0.05 μg/l), Cr (< 8 μg/l), Hg (<0.02 μg/l), Pb (<0.5 μg/l) and Zn (< 60 μg/l). The results confirm the possibility to treat tunnel wash water with sedimentation and flocculation and to discharge treated wash water to a recipient, provided particular attention is given to very sensitive water bodies.

The Little Grand Wash fault and the Salt Wash Graben in the Colorado Plateau of southeastern Utah emit CO2 gas from abandoned drillholes, springs, and a hydrocarbon seep. Similar CO2-charged water has also been emitted in the past, as shown by large localized travertine deposits and veins along and near the fault traces. The faults cut natural CO2 reservoirs and provide an excellent analog for geologic CO2 sequestration. The faults cut a north-plunging anticline of rocks consisting of siltstones, shales, and sandstones from the Permian Cutler Formation through the Cretaceous Mancos Shale. The Little Grand Wash fault has 260 m of throw and the stratigraphic separation across the Salt Wash Graben is 50 m. The fault rocks in the damage zone show hundreds of fractures, which decrease in density farther away from the faults. In specific areas, fractures with the presence of calcite mineralization indicate fluid migration and bleach zones from a few millimeters to 30 cm. This is evidence of past fluid migration directly associated with the fault zone. Calcite mineralization fills these fractures and is also deposited in a variety of other bed forms. Foliated fault gouge, 5 to 20 cm thick, forms clay smear structures with a scaly shear fabric in a zone l0 to 15 cm thick is seen in the fault core. The leakage is constrained to the footwalls of the northernmost faults throughout the area. Clay-rich gouge structures should be effective barriers to cross-fault flow . Well log, surface geologic, and geochemical data indicate that the CO2 reservoirs have been cut by the faults at depth, providing a conduit for the vertical migration of CO2 to the surface, but not for horizontal flow across the fault plane. Even though lateral cross-fault migration may be impeded, this study clearly indicates that there are possible migration pathways for the escape of CO2 from faulted subsurface aquifers, including aquifers faulted by "low-permeability" faults with clay gouge. Three-dimensional flow models show how the fault's maximum permeability in the damage zone is parallel to the faults, and the leakage though the damage zone is localized near the fold axis of the regional anticline. Direct dating of the clay in the fault gouge was done by ExxonMobil with 40Ar/39Ar methods, indicating that fault movement occurred between the middle Eocene and the end of the Miocene. During this time, the Colorado Plateau is interpreted to have been experiencing rapid uplift. The middle Jurassic, upper Jurassic, and Cretaceous rocks at the surface have been uplifted approximately 1.8 km since the end of the Eocene. This uplift may have influenced fault movement in the Colorado Plateau and along the Little Grand Wash fault, and Salt Wash and Ten Mile Graben. In evaluating these deep aquifers for CO2 sequestration, careful design and monitoring of the geological structure and stress regimes must be considered to avoid leakage.

Climate change and increased pressure on water resources through urban and peri-urban population growth present some major uncertainties to the sustainable provision of good quality water, sanitation and hygiene (WASH) services, particularly to small-scale decentralized systems which are considered more vulnerable compared to centralized systems. The concept of “resilience” could be useful when dealing with such uncertainties. It deals with planning for shocks and stressors which could help address long-term water security and sanitation challenges. The aim of this research is to explore the relevance of the concept of resilience in dealing with uncertainties for decentralized WASH systems. Through literature review, interviews (n=22) and group discussions (n=18), the relevance of the 7 resilience principles, developed by SRC, to WASH planning for decentralized systems was explored. WHO community water and sanitation planning guidelines were reviewed to determine how resilience could add useful aspects to management of decentralised WASH systems.  Results showed that the resilience concept is important in planning and management of decentralized WASH systems, since, with the resilience principles as a basis, there is potential to involve different stakeholders to share knowledge, skills and resources across multiple scales. The three resilience principles considered most important from the 7 SRC resilience principles for decentralized WASH were identified as: 1) Broadening participation, 2) Maintenance of diversity and redundancy, and 3) Management of slow changing variables and feedbacks. Other important WASH aspects missing from the resilience principles were: 1) Contextuality, 2) Accountability, 3) Equity and human rights, 4) Monitoring and maintenance, 5) Resource capacity. Two case studies served as examples of how decentralized WASH systems are managed in a high-income country (Värmdö, Sweden) and  a low/middle income country (MSETO, Kenya). In both cases, applied resilience principles were identified together with areas of improvement. With reference to resilience, Värmdö municipality showed strength in the flow of information (connectivity) between actors but lacked integrated WASH planning guidelines and diversity of water supplies. The MSETO project exhibited strength in overlapping responsibilities (polycentric governance) but lacked management of slow changing variables and feedbacks, linked to the lack of adequate re-sources. The analysis of WHO Water Safety Plans and sanitation safety planning guidelines through the resilience framework revealed that the WHO guidelines have a heavy focus on technical aspects and lack an integrated approach involving polycentric governance and complex adaptive system thinking. There is need for the revision of the guide-lines to incorporate community social aspects, strategies of improving water availability and consideration of complex adaptive systems thinking. Municipalities and practitioners are recommended to consider resilience principles as well as the identified missing aspects in WASH planning and interventions. Further research is needed investigating necessary conditions for the application of resilience principles and important trade-offs.

Before the arrival of Euro-Americans, the inland Pacific Northwest was settled by native people whose frequent intentional burning of the landscape promoted open stands dominated by large fire-resistant ponderosa pine. Fire suppression for nearly a century, livestock grazing, and logging of the largest trees has resulted in forests characterized by increased densities of small trees with closed canopies and unusually high fuel loads. Such structural changes to the forest ecosystem are particularly evident in the Blue Mountains of Oregon and Washington where forest managers are applying prescribed fire and thinning to reduce the risk of stand-replacing wildfire and reestablish stand structure characteristics seen prior to Euro-American settlement. Aboveground ecosystem recovery after disturbance is directly linked to the survival of ectomycorrhizal fungi (EMF) that form an obligate symbiosis with roots of tree species in the Pinaceae. EMF are critical for the uptake of nutrients by the tree host. The research comprising this dissertation explores the response of the EMF community structure and composition, live fine root biomass, and duff (decaying material) levels to (i) seasonal burning (fall vs. spring) and (ii) alternative fuel reducing restoration treatments (thinned only, prescribed burned only, thinned and prescribed burned). In both studies, treatments significantly reducing duff depth (e.g. fall burning and both restoration burning treatments) negatively impacted EMF species richness and live fine root biomass. The EMF community is characterized by a large number of species scattered at low frequencies across the sites. The frequent occurrence of a few species (e.g. Rhizopogon salebrosus and Wilcoxina rehmii), in both studies before and after treatment applications, demonstrates that some EMF species survive or rapidly reestablish after disturbance. The initial reduction of EMF species richness, fine root biomass, and duff levels after prescribed fire has important implications for whether managers can achieve the desired future condition of stands with large-tree retention and low fuel loads. The impacts of prescribed fire on the soil microbial community, along with the recovery potential of a site and the impending risk of stand-replacing wildfire in stands differing in structure from historic conditions, bear consideration when developing restoration prescriptions. / Graduation date: 2005