Oregon has been moving forward with biomass energy development. Large-scale biomass power and cogeneration (producing heat and electricity) have been the focus of the last twenty-five years, while small-scale thermal bioenergy installations (producing heat) have dramatically increased during the last decade. In eastern Oregon, bioenergy is closely linked to restoration...
Triple-negative breast cancer (TNBC) is a particularly aggressive molecular subtype of malignant cells that tends to proliferate quickly and is commonly resistant to traditional chemotherapy leading to relapses in prognosis more frequently than other forms of breast cancer (BCa) [1][2][3]. Current treatment options include surgical resection of cancerous tissue and...
Humans and viral disease are inextricably intertwined. Viral disease plays an immeasurable role in human life, from the disease and economic burden associated with every facet of contending with human viral disease, to managing the consequences of viral disease in organisms important to our food supply, economy, and entertainment. The...
Understanding the motivations behind the daily energy use practices of individuals may be very important for encouraging people to live more sustainably. This study delves into the motivations that influence the energy use of individuals in Corvallis, Oregon. Using a survey in conjunction with Energize Corvallis, the faculty, staff, and...
Oregon possesses a diversity of natural resources from the dense rain-soaked forests of the Coastal and Cascade ranges to the deep, fertile soils of the Willamette Valley to the arid and semi-arid Snake River Basin. In the Willamette Valley, water resources sustain agriculture, municipalities, hydropower, fish and wildlife, flood control,...
This MPP essay examines how states expand access to nutritious food for low-income families, focusing specifically on policies related to the Supplemental Nutrition Assistance Program (SNAP) and farmers’ markets. Coalitions made up of nonprofits focused on hunger, farmers, and health collaborate to impact relevant policies in their respective states. The...
The migrations upstream of pre-spawned adult steelhead (Oncorhynchus mykiss) and
downstream of post-spawned steelhead (referred to as "kelts") can geographically and
temporally overlap in the Snake River, leading to management challenges for populations
listed under the Endangered Species Act (ESA). This thesis describes the development and
application of a method...
With rising sea levels and more frequent exposure to extreme storms, coastlines worldwide are vulnerable to increased erosion and loss of natural marsh lands. In an effort to lessen these impacts, there is a growing practice of adapting hard or “gray” coastline protection techniques to more nature-based features that promote...
Ice–ocean interactions have profound consequences for the ocean and climate, influencing the rate of sea level rise. Submarine melt is commonly parameterized using a three-equation formulation for the heat, salt, and momentum conservation equations coupled to a buoyant plume model, together called plume-melt theory. However, recent direct observations of terminus...
Wind flow on vegetated coastal foredunes adapts to the local canopy drag, resulting in spatial gradients in bed shear stresses which contribute to the formation of localized bedforms (e.g., nebkha, shadow dunes). Numerous morphological properties of the plants, including canopy height and density, affect the wind flow dynamics and therefore...
Sediment convergence and divergence zones create subaqueous morphological features that range from ripples O (cm) to coastlines O (km). However, there is a gap in knowledge associated with quantifying the contribution of small-scale ripple mobility to the evolution of large-scale morphology. To address this gap, we investigate how small-scale ripples...
The formation of beach scarps is a challenging morphodynamic phenomenon that the coastal community has yet to capture in coastal change models. Understanding scarp formation is crucial to accurately predicting coastal erosion and vulnerability during extreme events, as models without parameters for scarp formation and development severely underpredict total erosion...
Nearly 24% of Formerly Used Defense Sites (FUDS) containing military munitions are in the nearshore coastal zone with approximately 30% of those sites containing heterogeneous sediment compositions of gravel-sand. Previous exploration in munition mobility was performed on beaches of sandy or muddy bottoms leaving the influence of heterogeneous sediment properties...
Sexual maturation and sex differentiation comprise facets of a
common theme: reproduction. The endocrine system regulates many
of the critical physiological processes necessary for reproduction and
offers a framework within which technologies can be developed for
controlling sexual maturation and sex differentiation. The studies
described in this thesis were undertaken...
I conducted field studies to determine the effect of insect herbivory and
intraspecific plant competition on ragwort Senecio jacobaea. The objectives were to
determine the patterns and causes in the distribution of the ragwort flea beetle
Longitarsus jacobaeae foraging among varying densities of ragwort, to measure the
behavioral and numerical...
An analytical method for predicting life-cycle maintainability labor costs is developed. The purpose of the analytical method is to allow the evaluation of products, based on life-cycle labor cost, early in the design process. The Boeing 737-300/400/500 Bleed Air Control System is used as a test model, and the results...
Alternative male phenotypes in salmonine fishes arise from individuals that mature as either larger and older anadromous marine-migrants or as smaller and younger freshwater residents. Variability in age and size of males at maturity is hypothesized to be preceded by early differences in growth in size and lipid storage. Water...
Background:
As Zika virus continues to spread, decisions regarding resource allocations to control the
outbreak underscore the need for a tool to weigh policies according to their cost and the
health burden they could avert. For example, to combat the current Zika outbreak the US
President requested the allocation of...
Full Text:
. Alfaro-Murillo1,2☯, Alyssa S. Parpia1,2☯, MeaganC. Fitzpatrick1,2☯, Jules
A. Tamagnan1, Jan Medlock3
Background:
As Zika virus continues to spread, decisions regarding resource allocations to control the
outbreak underscore the need for a tool to weigh policies according to their cost and the
health burden they could avert. For example, to combat the current Zika outbreak the US
President requested the allocation of...
Background:
As Zika virus continues to spread, decisions regarding resource allocations to control the outbreak underscore the need for a tool to weigh policies according to their cost and the health burden they could avert. For example, to combat the current Zika outbreak the US President requested the allocation of...
Sex differentiation in fish is a labile process that allows sex inversion in several species. The inherent capacity of fish germ cells to differentiate into oocytes or spermatocytes constitutes a key factor allowing for functional sex inversion. This thesis set out to determine the mechanism involved in steroid-induced sex differentiation...
Environmental factors such as chemical contamination can have immunomodulatory effects on the immune response of fish and may be contributing to the decline in salmonid populations by augmenting disease susceptibility. Xenobiotics can interfere with the immune system at several levels of complexity, and different immune cells and processes have variable...
The environment under which fish are maintained as broodstock before
reproduction is often stressful; however, the impact of stress on broodstock and gamete
quality is not well known. We investigated the effects of stress over the final stages (i.e.
the 3 months preceding ovulation) of sexual maturation of female rainbow...
Pacific lampreys (Lampetra tridentata) have declined in abundance in the Columbia River Basin. Although, the reasons for the decline are unclear, we suggest that development of hydroelectric dams and habitat alterations in tributaries as the main causes. The available knowledge of life history of Pacific lampreys and status from dam...
Submerged aquatic vegetation (SAV) species, such as seagrasses, are highly valued in estuaries because of the many economic, ecological, and cultural services that they provide, including shelter for fisheries, minimizing water turbidity, and improving am-bient water quality. SAV can also alter its physical environment by attenuating wave and current velocities,...
Recent observations of tidewater glaciers find that the currently accepted model for predicting ice melt vastly underestimates observed melt rates. The release of pressurized air bubbles into the ocean from pores in the ice is one process that can amplify glacier melt. To incorporate this process into models, we need...
Scour is the main cause of bridge failures in the United States. Bridge failures raise a hazard to the safety of the traveling public as well as the massive economic consequences due to the high cost of constructing a new or a replacement bridge. The Oregon Department of Transportation (ODOT)...
This work investigates a methodology for estimating the ocean stratification gradient based on high-resolution, in space and time, remote sensing observations of internal wave propagation speeds. The internal wave speed observations were collected using a shore-based, X-band marine radar and the ocean vertical density profiles were collected simultaneously from an...
Freshwater cyanobacterial blooms are a nuisance and health threat in the Pacific Northwest. The accepted methods of characterizing these blooms by microscopic cell counts cannot differentiate between toxic and non-toxic strains of the cyanobacterium Microcystis. Also, there is limited understanding of freshwater cyanophage that may control bloom dynamics. In order...
Due to the advancement of incredibly low power microcontrollers and small form factor integrated circuits, energy harvesting can be considered as an alternative, low power source for remote ocean sensing and measurements. To demonstrate the effectiveness of harvesting thermoelectric energy contained in the temperature differential between ocean surface water and...
Ocean Drifters are a low-cost and easy-to-use platform that are commonly used for studying ocean currents. With added interest in studying the ocean, emphasis has been taken to make it more accessible. A pilot course focused on introducing the topic of ocean sensing was announced. The HC 407 course will...
This full research paper explores two factors of increasing importance for first-year university engineering curricula: sustainability and diversity. Over the past fifteen years, many universities in the United States have adjusted their engineering programs in response to these two values expressed by industry, professional organizations, and the Accreditation Board for...
Estimating how large instream wood (LW) may impact local hydraulics is critical both for mitigating flood hazards and for ensuring intended habitat benefits of the LW are produced. In practice, the design of forms such as LW is limited by a lack of mechanistic tools for estimating how LW features...
Physical modelling is instrumental to the progression of coastal engineering research and our understanding of the offshore and nearshore environments. Scaled models are designed and built to be tested in coastal research laboratories, where a wave basin or flume generates the desired wave conditions for experimentation. The surrounding hydrodynamics of...
The coastal region is home to many types of surface fronts that exist on a submesoscale (1-10 $km$). While in situ observations capture point or transect observations of frontal behavior subsurface, their complex spatial patterns can be well-captured using remote sensing techniques, which provide synoptic views of the ocean surface...
Oregon leads the U.S. in the number and extent of established collaborative groups on national forests. Understanding similarities and differences in Oregon’s current forest collaboratives may aid more informed approaches to peer learning, policy, and technical assistance in public and private land natural resource management across the U.S. West. Our...
Early embryo development is dependent on maternally derived RNA and protein synthesized during oogenesis. In the bovine embryo this dependence lasts until the 8-16 cell stage, at which time embryonic transcripts become essential for continued development. One proposed mechanism for this transition from maternal to zygotic control of development (maternal...
The purpose of this work was to determine if environmentally-relevant concentrations of chlorpyrifos and copper, two commonly detected chemicals in Western surface waters, can negatively impact the biological health of salmonids. Both compounds are highly neurotoxic to fish, but each with distinct biological target sites and mechanisms of action. We...
While there are many more species of reptiles in the tropics than in temperate
latitudes, relatively little is known about the natural history of tropical species of
snakes. Even basic information, such as reproductive ecology and behavior, is lacking. Patterns of reproduction in tropical species differ from patterns in temperate...
Shell-boring polychaetes pose economic risks for oyster aquaculture industries as they reduce the aesthetic quality of oyster products by creating unsightly mud-filled blisters on the inside of the shell. Recently there has been a reported uptick in infested oysters on commercial farms along the west coast of the US, which...
The coast of Oregon is highly dynamic, with beach and dune morphodynamics constantly evolving in response to physical and ecological forcing at scales ranging from seconds to decades and meters to tens of kilometers. Evaluating spatial and temporal trends in shoreline evolution is paramount in understanding and eventually developing a...
In order to solve some classic problems in traditional topology optimization, such as unknown material distribution, checker-boarding and curse of dimensionality, this thesis introduces a new method to construct a mechanical structure that can reduce mass and increase stiffness. It uses a graph to represent the skeleton of a structure....
Wave energy has the potential to power large and small factions of economies around the world alike. Current methods for determining the amount of wave energy resource available to wave energy converter (WEC) devices entail capturing the look of the sea state at large by presenting characteristic wave heights, periods,...
The cultural and ecological values of Pacific lamprey (Lampetra tridentata) have not been understood by Euro-Americans and thus their great decline has almost gone unnoticed except by Native Americans, who elevated the issue and initiated research to restore its populations, at least in the Columbia Basin. They regard Pacific lamprey...
Chinook salmon are the largest of any of the salmon in Oregon. Mature fish range from less than 2 pounds to more than 70 pounds. In the late 1800s, chinook salmon were almost the only species taken for canning in the Columbia River, with production peaking at 43 million pounds...
Coastal cutthroat trout is one of three cutthroat subspecies found in Oregon. The coastal subspecies, which is closely related to steelhead/rainbow trout and Pacific salmon, displays the most diverse and flexible life history of any of the Oregon salmonids. Coastal cutthroat can be found in streams and rivers from the...
Anglers and naturelovers prize steelhead trout for their mystique and power. Oregon has two subspecies of steelhead (so-called because of the metallic appearance of maturing adults) or rainbow trout: a coastal form and an inland form.
A plant community classification was developed describing the comprehensive variation of oak vegetation currently occupying the Willamette Valley Ecoregion of western Oregon. Multivariate statistical analyses were used to classify field collected floristic and habitat data. Field sampling targeted minimally managed, homogenous vegetation stands with a significant oak component occupying at...