Grapevine red blotch virus (GRBV), the causal agent of red blotch disease (RBD) in grapevine, Vitis vinifera L., is an emerging pathogen of significance to the wine grape industry of Oregon, USA. To address knowledge gaps of GRBV epidemiology, spread of GRBV was evaluated in Oregon vineyards over four years....
The bi-directional relationships within the personal and contextual environments of adolescents are critical to the development of adolescents and their transition into adulthood. Opportunities for youth to participate in and provide leadership in meaningful programs, gain life skills, and interact with adults in sustained relationships are key features leading to...
The primary purpose of this study was to determine which factors related to adult 4-H volunteer empowerment in 4-H youth development settings. This study examined the relationship of adult 4-H volunteers’ perceived leadership styles of Oregon 4-H Youth Development Educators (YDE) to the adult 4-H volunteer sense of empowerment. In...
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related compounds are well-recognized for their immunosuppressive activity, which is mediated through an intracellular receptor and transcription factor, aryl hydrocarbon receptor (AhR). Laboratory animals exposed to TCDD are less resistant to infection and have severely impaired humoral and cell-mediated immune responses. This dissertation addressed the hypothesis that...
PART I. The concentration of nickel in some soils may be
insufficient to meet the requirements of enzymes such as
urease in soybeans and hydrogenase in Rhizobium. Nickel
availability in soils was examined by measuring microbial
urease activity in soils which were treated with glucose
and urea. Supplemental nickel was...
The Quotient Method (QM) is used by the United States Environmental Protection Agency (USEPA) in ecological risk assessments of pesticides for nontarget organisms. The QM requires several assumptions regarding exposure and hazards of pesticides to wildlife; several of these assumptions have not been tested. During 1997-99, I conducted three experiments...
The majority of our modern understanding of bacterial pathogenesis is based on the strategy that involves screening bacterial genomes for the presence of the genes encoding pathogenic factors, and analysis of these genes via forward and reverse genetics. Chlamydiae represent a unique group of pathogenic bacteria in which it is...
Damage estimates to the built environment from tsunamis are important for disaster mitigation, including planning emergency response and recovery. This dissertation evaluates the damage states of buildings in a small urban coastal city, Seaside, Oregon, from tsunami hazards generated by a Cascadia Subduction Zone (CSZ) event. This study is separated...