X-ray computed tomography is a noninvasive imaging modality capable of reconstructing exact density values of 3D objects. Computed tomography machines are deployed across the world to provide doctors with an image that reveals more detail than a standard x-ray image. We investigate algorithms based on exact computed tomography reconstruction formulas...
The adsorption equilibrium and kinetic behavior exhibited
by β-lactoglobulin at silanized silicon surfaces of varying
hydrophobicity were examined using ellipsometry. Adsorption
equilibrium results were used to construct adsorption
isotherms; the adsorbed mass of β-lactoglobulin was observed
to increase with increasing surface hydrophobicity, within a
defined range of hydrophobicity. Adsorption kinetics...
The marine climate of the Galapagos is spatially and seasonally
heterogeneous. A taxonomically comprehensive study of Galapagos zooplankton has
never been done. This study is an initial effort to establish the distribution and
community structure of zooplankton in the Archipelago. I collected zooplankton
samples by vertical tows over the Galapagos...
A study was done on the zoogeography of species of oceanic
shrimp in the North Pacific from 22°N to 56°N and from 124°W to
145°E, using samples of shrimp collected from 1954 to 1969. These
collections were made during the following cruises: John R. Manning
Cruise 22, and the Hugh...
Acquired Immune Deficiency Syndrome (AIDS) has become the world's foremost health threat and is the number one killer in Zimbabwe. Acquired Immune Deficiency Syndrome impacts not only the individual who has AIDS, but on nuclear and extended families, and all aspects of society in Zimbabwe. Since studies have indicated that...
Following the work of Asai, Kaneko, and Ninomiya for Faber polynomials associated to the modular group, and Bannai, Kojima, and Miezaki's partial proof for the case of the Fricke group of level 2, we show that the zeros of certain modular functions for some low-level genus zero groups associated to...
In this dissertation, we begin by presenting the result of F. K. C. Rankin and Swinnerton-Dyer on the location of the zeros of the Eisenstein series for the full modular group in the standard fundamental domain. Their simple but beautiful argument shows that all zeros are located on the lower...
In this dissertation, I present electronic spectra of a few polycyclic aromatic hydrocarbons (PAHs): tetracene, pentacene, pyrene, benzo[g,h,i]perylene and benzo[a]pyrene using resonantly enhanced multiphoton ionization (REMPI) and zero kinetic energy (ZEKE) photoelectron spectroscopy. The work of tetracene and pentacene also combine a laser desorption source with a ZEKE spectrometer, demonstrating...
In this dissertation, I describe spectroscopic studies of jet-cooled polycyclic aromatic hydrocarbons (PAH) and one nitrogen substituted PAH (PANH) using pulsed field zero kinetic energy (ZEKE) photoelectron spectroscopy and resonantly enhanced multiphoton ionization (REMPI) spectroscopy. Recently, there has been a demand for far-infrared (FIR) spectral information of astrophysically relevant molecules...
Cytokinins are a group of plant hormones mediating cell division and
differentiation. Zeatin is a naturally occurring and highly active cytokinin that is rapidly
metabolized in Phaseolus seeds. The metabolites and enzymes mediating the conversion
have been studied extensively. Zeatin metabolic enzymes may be utilized in studying the
regulation of...
Academic success is a salient domain of youth development and is related to positive lifelong outcomes among youth in foster care. However, youth in foster care experience compounding adversities, including maltreatment and foster care placement itself, which put them at risk of academic disengagement and underachievement. Despite these adversities, academic...
During the first full school year of the Covid-19 pandemic, two central contexts for adolescent development—home and school—changed utterly. In Oregon, most middle- and high schoolers attended school entirely remotely from the beginning of the pandemic, in March, 2020, through the end of April, 2021, removing both the supports available...
Harvesting costs were determined for commercial thinning of young stands to
achieve vegetation and wildlife objectives. This included replicated comparisons of
thinning treatments. Treatments were defined based on residual tree stocking after
thinning. Study procedures were developed and evaluated to improve statistical
relevance. Multiple linear regression models were used to...
In 2008, the “Great Recession” gained its momentum and quickly grew into a global crisis that led to massive gross domestic product declines and job losses in countries around the world. Relative to prior economic downturns, young adults were greatly affected by the Great Recession. This likely placed a premium...
Human alterations of landscapes take many forms, one of which is anthropogenic pollution. Mercury (Hg) is a complex contaminant because its uptake into the food web is not driven entirely by loading to the system; methylation is necessary to make Hg bioavailable and toxic to fish and wildlife. Because methylation...
This dissertation describes patterns in epiphytic macrolichen community composition along a nitrogen deposition gradient in the Yosemite region of the Sierra Nevada in California. This region is part of the largest federal air quality Class 1 designated air-shed in the western United States, covering the entire crest of the Sierra...
A laboratory-prepared hot-water extract of yeast is required
for vigorous growth of San Francisco sourdough bacteria (Lactobacillus
sanfrancisco) in pure culture. This requirement was examined
with the goal of determining what is unique about fresh yeast extractives
(commercial extractives exhibit much lower growth promoting
activity), and which components of fresh...
Reforestation of Pacific Northwest forest-lands with western hemlock has been hindered by unexplained plantation failures.
The purpose of this thesis is to provide information that will help in determining the cause of seedling damage and mortality. The studies focused on the relationship between xylem water potential, xylem cavitation and the...
Aquatic animals are exposed to a variety of natural and
anthropogenic xenobiotics. Biotransformation of xenobiotics was
examined in three aquatic animals: a primitive mollusc (chiton);
a shellfish which is an important human food source (oyster);
and, a lower vertebrate model for toxicological studies (rainbow
trout). Since digestive glands of Cryntochiton...
Reported here is an investigation to determine the in vitro and in vivo metabolism
of xanthohumol (XN). XN is the major prenylated flavonoid of the female
inflorescences (cones) of the hop plant (Humulus lupulus). It is also a constituent of
beer, the major dietary source of prenylated flavonoids. Recent studies...
Lamellar x-ray diffraction was studied from thin films of L-α-1,2-dipalmitoyl lecithin (DPL) and a 1:1 mixture (BrDPL) of L-α-l-palmitoyl-2-(9- bromopaimitoyl) lecithin and its 10-bromo analog. The specimens had high lamellar order, with an upper bound on the mosaicity of 6 mrad (0.4°) for DPL and BrDPL. With various water contents,...
Several dolphin species have global distributions. The extent of their radiation and limits to gene flow are presumably a product of oceanographic features both recent and historical, behavioral specializations and social organization. Rough-toothed dolphins (Steno bredanensis) are globally distributed in tropical and subtropical waters and are generally found in depths...
The purpose of this study was to identify and describe the underlying mechanisms within community colleges that influence cross-functional collaboration. The study also explored the role of community college leadership in fostering internal collaboration. The following questions guided the research: (1) What does cross-functional collaboration look like at a community...
Improvement behaviors, specifically double loop, have been linked to successful lean implementations. Although the lean literature supports individual cognitive transformation to double loop learning as an important element of lean success, there remains a strategic methodology to achieve sustainable double loop behavior. Perceptions toward behavior and employee satisfaction have been...
There is no doubt that adhesive penetration plays an important role in wood bondline joint performance and durability; yet, to date there is no direct experimental evidence linking penetration depth with bond performance. This is, in part, because adhesive penetration is commonly assessed with various 2D microscopy techniques that are...
Western redcedar (Thuja plicata Donn.) is a valuable commercial species found in
the northwestern United States and southwestern Canada. This dissertation includes four
papers focused on wood and stem characteristics of second-growth western redcedar, and
how those characteristics vary within the stem or how they are influenced by cultural
practices....
There are a number of wood properties which affect the quality of forest products such as lumber and pulp. Of these, wood density is considered by some to be the single most important physical characteristic because it is an excellent predictor of strength, stiffness, hardness, and paper-making capacities. Accurately assessing...
The purpose of this study is to critically explore low-income women's experience as they negotiate post secondary education in community colleges. Three research questions explore the context through which low-income women have entered the college experience, what that experience is like for them, and how the community college experience has...
The purpose of this study was to present the new women's
studies program for the community college. The study advocated
consciousness raising for females at all levels of public instruction,
but this paper was limited to the community college. The program
outlined would seek to help women to assume a...
Ten female survivors of physically assaultive domestic violence were
interviewed three times each in a feminist, qualitative study designed to access
their perceptions about their children's experiences in domestic violence. All
participants had children living with them at the time of the abuse and were one
to five years out...
Long-haul truck drivers are absent from their families for prolonged periods
of time. This paper examines the methods trucking families use to remain
connected given such absences. Interviews with ten women married to long-haul
truck drivers underwent qualitative analysis. Initially, personal profiles were
developed to illustrate life experiences of the...
A sample of 1,003 women, age 22 in 1983-84 and age 27 in 1988-89, were
selected from the National Longitudinal Survey of Youth. Personal, familial, and
geopolitical predictors of alcohol consumption were evaluated at each time period and
longitudinally. The study integrated macro- and micro-level influences to determine
their influence...
With women comprising nearly 50% of HIV/AIDS infections globally, the development of new woman-initiated HIV prevention methods has become a public health imperative. To date, the female condom and the diaphragm are the only woman-initiated prevention methods available on the consumer market. Recent research has focused on two HIV/AIDS prevention...
Generally presented as a preferred social norm based on both ethical considerations and legislative demands, gender equality has been highly encouraged in recent years. For instance, The United Nations Sustainable Development Goals for 2030 call out achieving gender equality and empowerment of women. However, although there are multiple efforts to...
An interpretative philosophical framework was applied to a case study to document the particular experiences and perspectives of ten women engineering transfer students
who once attended a community college and are currently enrolled in one of two university
professional engineering programs. This study is important because women still do not...
The dominant narrative of U.S. Muslims in higher education is associated with violent rhetoric, anti-American values, and terrorism. After terrorist attacks took place on September 11th, 2001, this narrative expanded to include a depiction of U.S. Muslims as being oppressed and submissive. Hate crimes, discrimination, and Islamophobic attacks towards Muslims...
The prevalence of Internet-of-Things (IoT) applications leads to an increasing focus on the design and optimization of sensor nodes. Battery lifetime and associated costs of battery replacement often limits the long term operation and viability of sensor nodes. RF wireless energy harvesting on the other hand can be appealing since...
This dissertation studies two different wireless microwave sensing applications in the subjects of environmental monitoring and biomedical devices. The environmental sensing application presents a design of novel wireless sensor node configurations. These nodes are intended to be used specifically in a built environment of railroad track ballast for its health...
The southwest monsoon, which may be idealized as the northward movement of the intertropical convergence zone in the Indian Ocean associated with differential heating of land and ocean, brings a seasonal reversal of currents and winds in the Bay of Bengal and the Arabian Sea. Atmospheric convection from monsoon activity...
In order to estimate wind turbine residL2;characteristics
in the presence of atmospheric turbulence, the important atmospheric
sources for the force excitations felt by the wind turbine system
must be identified and characterized. The goal of this research
is to develop the wind turbulence input model for horizontal axis
wind turbines....
An experimental study was made of the average and turbulent
wind characteristics of the flow over a model of a coastal headland.
The scale of the model was 300:1, corresponding to a prototype size
of 500 m.
The data for validation of the model study was obtained from
instruments mounted...
The major historical studies that have examined American
biology have emphasized the development of experimental biology at
the end of the nineteenth century. In this characterization, the
descriptive branch of biology has often been treated as less than
important and, in several cases, as a hindrance in the application
of...
With continual and worldwide human population growth, our impact on the natural environment expands and intensifies every day. We consume natural resources, burn fossil fuels, and release toxic compounds into the air, water, and earth. We build roads that fragment the landscape, construct new settlements, and develop agricultural lands in...
In this dissertation, I examine how the spatial configuration of forest ownership influences the risk-mitigating behavior of public and private forestland owners over time. I determine whether or not the predicted equilibrium outcomes are socially optimal and, if not, whether the introduction of regulation, liability, or private insurance would lead...
Low-distortion architecture is widely used in wideband discrete-time switched-capacitor delta-sigma ADC design. However, it suffers from the power-hungry active adder and critical timing for quantization and dynamic element matching (DEM). To solve this problem, this dissertation presents a delta-sigma modulator architecture with shifted loop delays. In this project, shifted loop...
Nowadays, needs for wideband and high accuracy analog-to-digital converter are increasing rapidly in manifold applications such as wireless communication, digital video and other consumer electronics. Besides, low power consumption is required to have longer battery life in portable systems. CMOS technology scaling and innovative modulator topology make the implementation much...
There is a significant need in recent mobile communication and wireless broadband
systems for high-performance analog-to-digital converters (ADCs) that have wide
bandwidth (BW>5-MHz) and high data rate (>100-Mbps). A delta-sigma ADC is
recognized as a power-efficient ADC architecture when high resolution (>12-b) is
required. This is due to several advantages...
The work presented here is focused on applying basic principles of solid-state chemistry to the study and development of new wide band-gap semiconductors and insulators for photovoltaic and electronic-device applications. Analysis of crystal structure, band structure, optical band gap, morphology and transport properties provides fundamental insight into materials performance as...
Legumes are defined as the immature, germinated, or mature edible seeds of legume plants (Fabaceae). The primarily consumed legumes are dry beans, dry peas, lentils, chickpeas, cowpeas, fava beans, and pigeon peas, which are grouped as mature legumes, green beans and peas, which are considered green legumes, and sprouted or...
Resource availability follows seasonal cycles in environmental conditions. To align physiology and behavior with prevailing environmental conditions, seasonal animals integrate cues from the environment with their internal state. One of the systems animals use to integrate those cues is the hypothalamus-pituitary-adrenal (HPA) axis and its primary effector, glucocorticoid hormones. The...
The purpose of this study was to explore motivations behind participation in cosplay and the use of social media among cosplayers who maintain Facebook Artist Pages. Further focus was placed on investigating the role of Facebook Artist Pages in building fame. To explore such motivations, two theories were referenced: Deci...
A five year longitudinal study was begun in 1976 to find a
solution to the problem of early primary children who fail in school
and then adopt the failure syndrome. The study was conducted in four
elementary schools in Oregon which had distinctly different
socio-economic populations.
The tests used for...
Calls for increased farmer involvement in research and extension programs
have been numerous and well supported. One approach to integrate the collective
knowledge and experience of agricultural scientists and farmers is through whole
farm case studies (WFCS). An interdisciplinary team of 34 research and extension
personnel at Oregon and Washington...
A qualitative research approach composed of three strategies was employed to systematically examine the politics of natural resource collaboration. First, using the Oregon Plan for Salmon and Watersheds as a case study, the behavioral assumptions of natural resource policy instruments enabling collaboration were uncovered and analyzed. Three key assumptions emerge:...
Rural farmers in Tanzania depend on subsistence agriculture for their livelihood. Poor soil conditions, and the danger of drought, increases the risk of cyclical poverty conditions. Aid organizations, including the World Agroforestry Centre (ICRAF) and the Millennium Development Projects (MDP), as well as industrial tobacco industry, have provided development programs...
This research examines two questions: 1) What stories do Christian teacher educators tell about their own White racial identity development? and 2) Is there an impact of studying White racial identity development on the praxis of Christian teacher educators? If so, in what ways? The researcher began the project with...
The purpose of this qualitative study was to examine the experience of white principals in understanding their white identity, privilege, and power as they worked to implement socially-just and culturally proficient schools. The findings offer insights into the following questions: 1) How do white school leaders view white identity and...
The Newell Farmstead (35MA41) archaeological site lies in the heart of the French Prairie in the Willamette Valley in the Champoeg State Heritage Area, Oregon. The integrity and depth of deposition have made the Newell site a unique opportunity to look at activity areas and domestic life of early Euro-American...
Affective reactions to daily stressors are known mechanisms through which daily stressors impact health and well-being (e.g., Charles et al., 2013; Piazza et al., 2013; Sin et al., 2015; Stawski et al., 2019). Therefore, understanding what may promote resilience or vulnerability to such affective reactions is imperative. Theoretical perspectives (Almeida,...
This dissertation for the degree of Doctor of Philosophy in Public Policy addresses two main research questions. On a macro-level it aims to answer how gender ideologies, as seen in attitudes towards the gendered division of labor, develop over time in the context of changing family policy regimes. On a...
This study proposed a theoretical model of choice overload and empirically examined the model in the context of online apparel shopping. The purpose of the study was to investigate how the number of choices and product presentation formats influenced consumers’ online apparel shopping experience as well as how the formed...
This dissertation has focused on lignin byproducts that result from the alkali processing of wheat straw. The first study evaluated the application of “standard” lignin quantification methods for summative analyses of alkali-based processes. Mass closure during NaOH processing at 25, 50, and 75°C of wheat straw was evaluated using the...
Concerns have been expressed that wheat (Triticum aestivum L.) cultivars selected under optimum conditions may lack adequate adaptation for stress environments. Experimental populations were grown under three environmental conditions 1) optimum, 2) reduced irrigation, and 3) high temperature. Field experiments were conducted at the Center for Northwest Experimental Station (CIANO),...
Wheat is a staple food crop with many applications. The composition and quantity of major and minor flour components greatly influence functional dough properties, processing quality, and end-use suitability. Seven to 15% of the weight of wheat flour is protein and the gluten proteins comprise 80-85% of that. The gluten...
Urban African American adolescents exhibit high levels of risk behavior, disproportionately high rates of sexually transmitted infections (STIs), and are at risk for acquiring Human Immunodefiency Virus (HIV). To date, interventions that address the high rates of STIs in this population demonstrate only moderate efficacy. As researchers strive to develop...
The myxozoan Ceratonova shasta is an intestinal parasite of salmon and trout that causes ceratomyxosis, a disease characterized by severe inflammation of the intestine that can lead to hemorrhaging, necrosis, and death of the fish host. The parasite is endemic to the Pacific Northwest of the United States and Canada,...
Near-surface advanced argillic hydrothermal alteration zones, also referred to as lithocaps, are characterized by quartz, alunite, clays (pyrophyllite and kaolinite group minerals), and minor F-bearing aluminosilicates (i.e., topaz, zunyite, diaspore, and APS) that form where water-, SO2-, and HF-rich gas condenses into shallow groundwater, acidifies, and reacts with rocks. The...
Corals have multiple roles in maintaining ocean health and are some of the world’s most diverse ecosystems. The coral animal is host to a multitude of taxa, including symbiotic dinoflagellate algae, fungi, bacteria, protists, and viruses. Environmental stressors and disease agents can perturb the delicate balance of the coral host...
Issues of injustice in society (e.g. racism, classism, sexism, ableism) are perpetuated in and through educational opportunities, including mathematics learning (Freire, 1970/2000). Those that are committed to disrupting the interlocking systems that create disparities and oppression in mathematics education are considered to be “pursuing justice.” Pursuit of justice can involve...
A widely held belief is that the pre-2018 U.S. repatriation tax has led to stockpiles of cash of multinational corporations being trapped overseas, but there is evidence showing that firms are issuing debt to access cash. Standard and Poor has documented this phenomenon as “synthetic cash repatriation.” This study examines...
Nonalcoholic fatty liver disease (NAFLD) is characterized by an accumulation of neutral lipids in the form of triglycerides and cholesterol esters accounting for >5% of liver weight. Excess neutral lipids accumulate in large lipid droplets, i.e., macrosteatosis, displacing the nucleus of cells. Current theory suggests neutral lipid accumulation is the...
West Nile Virus (WNV), a vector-borne disease continues to be a serious threat to public health in the United States, particularly in the Southwest region. While all the states in the U.S. experienced a decreasing trend of WNV disease in 2010, the state of Arizona experienced a sharp increase from...
The publicly subsidized Federal Crop Insurance Program has expanded rapidly in recent decades in the United States. With the reform in the 2014 Farm Bill, the Federal Crop Insurance Program has become the most important component of U.S. farm policies. The primary goal of the program is to provide risk...
The purpose of this study was to determine the effects of long-term weighted vest
exercise on hip bone mass, functional ability and static balance in elderly women. This was
a within subject exercise intervention study and included a 6-month control period.
Twenty-three subjects (age 85 ± 6) were recruited and...
The purpose of this study was to explore the relationships between weight stigma consciousness, perceived body appearance, social physique anxiety, and the health outcomes of physical activity levels and eating behaviors. Select precursors were also examined. These relationships were based on Harter's model of self-worth. Two-hundred fifteen adults with a...
Having excess weight carries a negative social stigma in the U.S. Previous research has shown that experiencing stigma has negative physical and mental health consequences. Few studies have examined how experiencing weight stigma might act as a barrier to engaging in healthy behaviors among older adults. The purpose of this...
The current appeal of reality television is undeniable, with the specific genre of makeover television having special nationalistic and moral appeal in the United States. Previous analyses of NBC's weight-loss makeover show The Biggest Loser suggest that the program is inherently problematic because of its ingrained fat bias and unethical...
Biogeochemical data from four small watersheds in the Silver Creek study area, southwestern Idaho, provide the basis for: 1. An estimate of chemical and erosional denudation rates (CD and ED), 2. an estimate of plagioclase weathering rate, 3. a rational basis for estimating the rate of nutrient supply to soil...
The role of weather in influencing tourist-recreation visitation
to the Oregon coast during the six-month summer season of May
through October has been investigated by this research. In addition,
the normal day-to-day fluctuations in coastal visitation has been
determined.
Based upon the normal visitation, the tourist-recreation season
on Oregon's coast...
The importance of physical activity is well documented (Haskell et al., 2009a; McReynolds & Rossen, 2004; Steinbeck, 2001). Despite physical activity’s benefits, many individuals are not meeting current weekly physical activity guidelines recommending ≥ 150 minutes of moderate or ≥ 75 minutes of vigorous aerobic physical activity and 2 or...
The thesis focuses on activity recognition from sensor data, which has spurred a great deal of interest due to its impact on health care and security. Previous work on activity recognition from multivariate time series data has mainly applied supervised learning techniques which require a high degree of annotation effort...
Efficient time-series analysis can impact multiple application domains such as motif discovery in gene analysis or music data, extracting spectro-temporal patterns in acoustic scene analysis, or annotating and classifying electrical bio-signals (such as ECG, EEG, and EMG) for medical applications.
Time-series analysis involves a variety of tasks.
To predict future...
In supervised learning, label information can be provided at different levels of granularity. For small datasets, it is possible to acquire a label for each data instance. However, in the big-data regime, this fine granularity approach is prohibitively costly. For example, in semi-supervised learning, only a limited number of samples...
In this dissertation I explore the Arms representation and activities for teaching quantum mechanics invented at Oregon State University. In the Arms representation students embody quantum states. The Arms activities are presented as an exemplar of the unique physics classroom culture of the upper-division Paradigms in Physics program. In the...
Childhood obesity prevalence is significantly higher among adolescent 12-19 years old than younger age groups. Youth athletes are overlooked by childhood obesity prevention programs. WAVE~Ripples for Change (WAVE) program is a 2-y obesity prevention intervention with high school (HS) soccer players (14-19y) using a mixed virtual- and physical-world learning environment...