Invasive species are a major threat to global biodiversity. Understanding the mechanisms underlying successful invasions is imperative for developing effective management strategies. Plasticity in physiological, morphological, and behavioral traits could be an indicator of invasion potential in non-native species. The invasive American bullfrog (Lithobates catesbeianus) has recently been observed breeding...
Fundamental objectives in the field of conservation biology involve understanding the processes that influence small and declining populations and applying that knowledge to develop appropriate monitoring strategies and targeted management and conservation actions. Critical first steps in determining the relative role of factors that drive population declines involves estimation of...
Agricultural water supplies are becoming increasingly uncertain in the western United States due to elevated demands from competing water users, environmental restrictions on surface water withdrawals as a result of the establishment of the Endangered Species Act in 1973, and potential climatic changes. Since many rural communities in the West...
Oblique subduction of the Juan de Fuca plate beneath the North American plate characterizes the tectonic setting of the Pacific Northwest. North American plate deformation at the latitude of central Oregon consists of the clockwise-rotation of the Siletzia block in the forearc and the extensional Basin and Range province in...
This work describes a method for incorporating patient data into a nutrient transport model of the intervertebral disc.This data was collected using MRI diffusion weighted imaging (DWI), and was converted into an apparent diffusion coefficient map (ADC map). This map was used to define the diffusion behavior of water within...
Streaming media and interactive television viewing experiences are becoming more commonplace with the introduction of services such as Netflix Streaming, the Apple TV, and Google TV aided by the increase adoption of broadband internet. As these services make their way into the living room, and developers struggle to accommodate more...
Forward pricing is a marketing tool available to Pacific
Northwest white wheat growers for reducing price risk.
The cash forward contract is the traditional pricing mechanism
used for this purpose. In September 1984, another option
for forward pricing was made available through the introduction
of a new futures market for...
Cryptographic systems are used for secure communications in the government, in industry, and by individuals. Many cryptographic systems base their security on our inability to factor quickly. For this reason, in the last few decades several fast factoring algorithms have been developed. The Quadratic Sieve is one of the best...
A Kalman filter was developed to recover information on short period variations of ocean circulation from the satellite altimeter signals for the North Pacific Ocean. The ocean circulation at each grid point is specified by three variables: sea level height h, zonal velocity u, and meridional velocity v. In our...
Geotechnical engineers design and analyze the interface between the natural and built environments, often based on uncertain and inherently variable data due to the nature of the building material, soil. Engineers must estimate the subsurface conditions at a site using historical, in-situ, and laboratory testing data. However, only discrete representative...
Coastal stream basins are of great importance to efforts aimed at refining our understanding of the earliest populations that inhabited the ancient Oregon coast. However, geomorphic responses to post-glacial sea level rise in these settings has produced depositional environments that destroy or deeply bury late Pleistocene and early Holocene-age archaeological...
Despite being internationally recognized as basic human rights, water, sanitation, and hygiene (WASH) insecurity continues to exist throughout the United States, particularly among low-income and unhoused portions of the population. Previous investigations into the intersection of WASH and people experiencing homelessness (PEH) in the US have primarily taken place in...
To understand the processes that lead to the formation of the oceanic crust, one must know the composition and the depth at which primary melts originate. Towards this end, this dissertation focuses on plagioclase-hosted melt inclusions from plagioclase ultraphyric basalts (PUBs). Plagioclase is usually considered to be the second phase,...
The Hampton Tuff is a 3.9 ± .02 Ma (2σ) ignimbrite sheet from the High Lava Plains of central Oregon. The majority of known outcrops exist to the north, within ~22 mi (~35 km) of the Frederick Butte Volcanic Center, the proposed source of the tuff. Thickness of the tuff...
Crystal-rich (40-50 vol.%) intermediate lava has been the primary eruptive product of several recent hazardous eruptions: Mt. Pinatubo, Philippines (1991), Soufriere Hills, Montserrat (1995-present), and Unzen, Japan (1990-1995). Despite this association with such devastating eruptions, the formation, timing, and evacuation of such magma is not well understood: do such eruptions...
The Pebble porphyry Cu-Au-Mo deposit in Alaska is one of the world's largest Cu-Au mineral resources. Late Cretaceous magmatic evolution in the Pebble district culminated with the intrusion of the Kaskanak Batholith and associated porphyry copper-gold-molybdenum mineralization. The Kaskanak Batholith is a multiphase granodiorite intrusion with an estimated footprint of...
Understanding continental crust formation and modification is a fundamental and longstanding geologic problem. Influx of mantle-derived basaltic magma and partial melting of the crust are two ways to drive crustal differentiation. This process results in a low density upper crust and denser, more refractory lower crust, creating significant and vastly...
Comprehension of eruptive histories is critical in understanding the evolution of magmatic systems at arc volcanoes and may supply evidence to the petrogenesis of intermediate and evolved magmas. Within the 300 ka eruptive history of Mount St. Helens, Washington, the Kalama Eruptive Period, 1479- ~1750 CE was bracketed by interludes...
Establishment of marine protected areas (MPAs) has been documented to effectively manage marine resource's diversity and enhance fisheries productivity. However, there must be a critical consideration of how these sites are selected and the actual description of the site itself. Its effectiveness is greatly dependent on understanding these habitats and...
Shallow landslides are destructive natural hazards that result in widespread losses, both of infrastructure and lives, throughout the world. To help mitigate the impact of landslide hazards, they are commonly characterized across a regional scale by (1) their location and likelihood using susceptibility maps, (2) their magnitude and frequency using...