Tetrachlorethene (PCE) and trichloroethene (TCE) were common solvents used in the 1970’s that are now frequently observed groundwater contaminants. One method of remediating these contaminants is in-situ bioremediation that uses a dechlorinating microbial population. The microbial population performs the sequential reductive dechlorination of PCE and TCE to cis-1,2-dichloroethene (c-DCE), vinyl...
Many Gram-negative bacteria use a type III secretion system (T3SS) to establish associations with their hosts. The T3SS is a conduit for direct injection of type-III effector proteins into host cells, where they manipulate the host for the benefit of the infecting bacterium. For plant-associated pathogens, the variations in number...
Questions: Mountain systems have high abiotic heterogeneity over local spatial scales, offering natural experiments for examining plant species invasions. We ask whether functional groupings explain non-native species spread into native vegetation and up elevation gradients.We examine whether non-native species distribution patterns are related to environmental variables after controlling for elevation...
Global environmental change is causing local extinctions of species. When species depend on one another, as in the mutualistic relationship between plants and pollinators, loss of one interaction partner may cause cascading effects within the community – such as additional extinctions and reduced pollination services. Network theory provides a way...
This dataset includes species richness of native plants, pollinators and birds as well as 13 proxies for ecosystem services representing timber production, culturally-valued plants and animals, and regulating services tied to forest productivity. The data were collected from an experiment conducted in the Oregon Coast Range USA that sought to...
This study investigated complete reductive dechlorination of chlorinated aliphatic hydrocarbons (CAHs) over a broad range of concentrations. Tetrabutoxysilane (TBOS), as a slow-release anaerobic substrate, was studied for enhanced reductive dechlorination of tetrachioroethylene (PCE) present as a dense non-aqueous liquid (DNAPL). Four different site-mixed cultures were used in the study: Site-300...
We explored relationships between photophysical processes and solar cell characteristics in solution-processable bulk heterojunctions (BHJs), in particular: (1) polymer donor:fullerene acceptor:small-molecule (SM) nonfullerene acceptor, (2) polymer donor:SM donor:SM nonfullerene acceptor, and (3) SM donor:SM nonfullerene or fullerene acceptor. Addition of a nonfullerene SM acceptor to “efficient” polymer:fullerene BHJs led to...
Biological invasions threaten native biodiversity, alter ecosystem function, and are a major cause of economic losses across the planet. The most impactful invaders alter disturbance regimes and initiate state shifts to outside the historical range of variability of the ecosystem. Concern for ecological and economic losses has prompted a rapid...
Chlorinated ethenes are common groundwater contaminants that may be treated through in-situ bioremediation. Relationships between the reducing environment, available electron donors and acceptors, reaction kinetics, and microbial community composition must be further understood to successfully engineer remediation schemes in the complex subsurface environment. This thesis work investigated the effect of...
Halogenated organic compounds have had widespread and massive applications in industry, agriculture, and private households, for example, as degreasing solvents, flame retardants and in polymer production. They are released to the environment through both anthropogenic and natural sources. The most common chlorinated solvents present as contaminants include tetrachloroethene (PCE, perchloroethene)...