The thrust of this thesis is to study oral solid dosage formulation using hot melt coating method and to use pharmacokinetic modeling and simulation (PK M&S) as a tool that can help to predict pharmacokinetics of a drug in human and the probability of passing various bioequivalence criteria of the...
For the west coast of North America, from northern California to southern Washington, a habitat suitability prediction framework was developed to support wave energy device siting. Concern that wave energy devices may impact the seafloor and benthos has renewed research interest in the distribution of marine benthic invertebrates and factors...
This thesis consists of extensions of results on a perpetual American swaption problem. Companies routinely plan to swap uncertain benefits with uncertain costs in the future for their own benefits. Our work explores the choice of timing policies associated with the swap in the form of an optimal stopping problem....
The HyperLogLog (HLL) algorithm is used to estimate the cardinality of large sets. This thesis gives a novel analysis of the HyperLogLog algorithm by using techniques from statistics and probability. Initially, closed form bounds for the mean and variance of the max of n independent and identically distributed geometric random...
I investigated the relationship between harlequin duck (Histrionicus histrionicus) behavior and lack of recovery from the Exxon Valdez oil spill in Prince William Sound, Alaska. First, I evaluated the hypothesis that harlequin ducks in winter have little flexibility to increase foraging time in response to disturbance because they are constrained...
Diet variation among individuals within populations is widespread. Often diet differences among individuals are attributable to obvious differences among individuals such as age, sex, or morphology. However, growing evidence suggests that individual diet variation is also common among seemingly identical individuals within populations. This phenomenon has been termed individual diet...
In this study we use a combination of data from forest inventories,
intensive chronosequences, extensive sites, and remote sensing, to make estimates
of biomass and net primary production (NPP) for the forested region of Western
Oregon. Plot-level forest inventory data were provided by the USDA Forest
Service through their Forest...
Climate change will impact the location of suitable habitat for tree species in the Pacific Northwest. Locations that become unsuitable will experience increased levels of tree mortality and diminished levels of tree growth. Understanding how these impacts will spatially manifest is vital for efficient management of natural resources. An invaluable...
Biological invasions and climate change represent two preeminent threats to ecological communities and biodiversity, altering the distribution and abundance of species, disrupting existing species interactions and forming unprecedented ones, and creating novel ecological communities. Many of the most successful invasive species are also ecosystem engineers, species that physically modify the...
In this thesis, high resolution ocean models are used to evaluate and forecast coastal ocean variability in two different applications. In the first study, the 2-km resolution ocean circulation model for the Eastern Bering Sea is utilized to understand whether slope-interior exchange along the path of the Aleutian North Slope...
The spreadsheet has become a common technology tool and is now a predominant form of end-user programming. Some of the same features that make spreadsheets excellent tools for ad-hoc development can introduce errors into the final product. Although a variety of research has been performed investigating methods to detect errors...
Emerging infectious diseases impact both human and wildlife populations. Infectious agents, in particular the aquatic fungus Batrachochytrium dendrobatidis (chytrid), have an influential role in driving global amphibian population declines. The emergence of the chytrid fungus has aspects of both geographic spread as well as climate shifts altering environmental conditions and...
Business is a social institution and society has always designated a role for
business which has been undergoing changes with changing societal values and
paradigms. Thus while business has always had some responsibilities, the modern
connotation of the words corporate social responsibility commonly refers to business
assuming responsibilities in economic,...
With increased resource development on the western Arctic coastal plain of Alaska (especially within the oil extraction industry) it is important to understand the basic life history attributes of whitefish stocks in the region in order to ensure appropriate management. These fish are a crucial part of subsistence harvests for...
Staling in beer is inevitable. Oxidation and increased temperatures are the main causes of stale flavors in bottled beers. Since 1934, research has been done to identify compounds and pathways involved in creating stale flavors. Although many research papers report stale flavors, there is not a lexicon per se of...
This dissertation describes the development of a new sustained release formulation of nifedipine. The new formulation was developed by coating commercially available immediate release soft elastic gelatin capsules using a spray coating technique with two different polymeric combinations. Dissolution studies were conducted and showed that controlled release of nifedipine was...
Species' distributions across the landscape are perhaps the least understood yet most conspicuous features of life on earth. Ecologists have long studied species' distributions; yet, many questions remain about why species occur where they do. Such questions persist largely because species' distributions are complex systems with challenging properties like non-linearity,...
Interest is expanding for the potential role of estuaries, particularly seagrass and salt marsh habitats, to sequester carbon, mitigate ocean acidification, and support abundant fisheries. The important functions of estuaries are part of a broader set of ecosystem services, or benefits to humans, which are regulated by ocean and watershed...
Effects of whey concentrate crystallization parameters of temperature, pH, and length of time of crystallization on lactose crystal forms and amount of lactose crystallized were investigated. Effect of crystallization parameters on freeze-dried powder quality was also investigated. Lactose crystal forms were observed in x-ray crystal diffraction patterns of freeze-dried whey...
Alfalfa accumulates phytoestrogens and when ingested binds the estrogen receptor and induces morphological changes similar to endogenous estrogens. The objective of this study is to evaluate morphological changes in uteri, vulva, and teats of ovariectomized prepubertal ewe lambs. Eighteen prepubertal ewe lambs were ovariectomized in November 2000 and fed nonestrogenic...
The purpose of this study was to investigate the survival and movements of newly metamorphosed Northern Red-legged frogs (Rana aurora aurora) as they emigrated from two ephemeral breeding ponds. Quantifying survival and movement rates will be important to our understanding how changes to terrestrial and aquatic systems affect behavior and...
Airborne discrete-return lidar is an active remote sensing technology capable of obtaining accurate, fine-resolution three-dimensional measurements over large areas. Discrete-return lidar data produce three-dimensional object characterizations in the form of point clouds defined by precise x, y and z coordinates. The data also provide intensity values for each point that...
Variable-retention harvesting was proposed to reduce loss of biodiversity and ecosystem processes associated with late-seral Douglas-fir (Pseudotsuga menziesii) forests in the Pacific Northwest. The Demonstration of Ecosystem Management Options experiment was established to test this hypothesis. Analysis presents various challenges to drawing statistical inferences about treatment effects. This dissertation explored...
The United States of America and the world are faced with three massive intertwining challenges at this time: COVID-19, racial inequity, and climate change. As a species, humans must come together and collectively address these challenges to preserve our humanity and make our world a more just and livable place...
The extreme value index (EVI) links the generalized extreme value (GEV) distribution and the generalized Pareto (GP) distribution. These two distributions are fundamental in extreme value theory (EVT), with the GEV distribution being the only possible non-degenerate limiting distribution of properly normalized maxima of iid random variables, and the GP...
Ecologists have long questioned why fluctuating populations tend to persist rather than go extinct. Populations that persist indefinitely are regulated by mechanisms that cause demographic density dependence, which works to bound fluctuation above zero. In a series of studies, I have sought to determine the processes and mechanisms that regulate...
This dissertation is about statistical methods for data analysis using generalized linear mixed models (GLMMs) with censored covariates. Special attention in given to the particular problem of inference about age-specific reproductive success in wild animal populations using some animals with known ages and some animals with ages only known to...
Background
Bcl11b, previously CTIP2, is a zinc finger nuclear transcription factor involved in the development of keratinocytes, teeth, T lymphocytes, and nervous tissue. Expression of Bcl11b has been reported in human head and neck squamous cell carcinoma (HNSCC) and increased expression correlates with poorly differentiated tumors. This study aimed to...
Achieving and maintaining sustainability in irrigated agriculture production in the era of rapidly increasing stress on our natural resources require, among other essential actions, optimum control and management of the applied water. Thus, a significant upgrade of the currently available soil water monitoring technologies is needed. The primary goal of...
Although machine learning systems are often effective in real-world applications, there are situations in which they can be even better when provided with some degree of end user feedback. This is especially true when the machine learning system needs to customize itself to the end user's preferences, such as in...
High severity fire is a historical and integral disturbance process in coniferous
forest types. Compounded disturbances such as multiple fires or post-disturbance
management activities are increasingly common, but ecological responses are not well
understood and may represent novel types of disturbances. I studied bird and small
mammal communities in the...
For data following a balanced mixed Anova model, the standard Anova method typically leads to exact F tests of the usual hypotheses about fixed effects. However, for most unbalanced designs with most hypotheses, the Anova method does not produce exact tests, and approximate methods are needed. One approach to approximate...
This dissertation is about the likelihood analysis of ordered categorical responses in a longitudinal/spatial study, meaning regression-like analysis when the response variable is categorical with ordered categories, and is measured repeatedly over time or space on the experimental or sampling units. Particular attention is given to the multivariate ordinal probit...
Ecologists must increasingly balance the need for accurate predictions about how ecosystems will be affected by climate change, against the fact that making such predictions at the ecosystem-level may be infeasible. Although information about responses of individual species to a changing environment is increasing, scaling such information to the community...
When data are not missing at random, approaches to reduce nonresponse bias include subsampling nonresponding units and modeling. The objective of this thesis is to develop unbiased and precise model-assisted estimators of the population total that are applicable to data from a complex survey design with nonignorable nonresponse. When information...
Aquatic ecological investigation is expanding to encompass considerations of
multiple scales across large landscapes. Much of the analysis included in this work
focuses specifically on coho salmon (Oncorhynchus kisutch) in multiple subbasins on
the Oregon coast. Coho salmon were chosen for an investigation of spatial scales,
network connections, and life...
Regression calibration inference seeks to estimate regression models with measurement error in explanatory variables by replacing the mismeasured variable by its conditional expectation, given a surrogate variable, in an estimation procedure that would have been used if the true variable were available. This study examines the effect of the uncertainty...
Small remnants of 'natural' habitats exist today throughout much of the world. Upland prairies in the Willamette Valley, Oregon have been nearly eliminated by conversion to agriculture and other uses. As a result, very few prairies remain and at least four butterfly species that require this habitat appear to be...
Approximately one in six children in the United States has a developmental disability (CDC, 2018). Among a wide variety of interventions that have been developed to support the health, wellbeing, and development of youth with disabilities, Animal-Assisted Interventions (AAI) have become increasingly prevalent. Some AAI involve youth participating with their...
Calls continually are made to provide economic assessments of research program achievements and efficiency. Yet little effort has been given to develop an assessment framework that would focus on the research discovery itself, treating the research manager as a producer and the research technology as a knowledge production function. The...
Natural selection, in its most basic form, is described as a process in which traitsincrease or decrease in frequency depending on their fitness, and only the trait withthe highest fitness will remain in the population. Yet, populations rarely have asingle `optimal' trait. The way natural selection maintains this observed variationwithin...
Understanding the origin and nature of intra specific biodiversity enables us to better conserve and manage animal populations. Biological diversity is seen at different scales and for different traits such as behavior, morphology, physiology, and life history. Behavior is especially important since behavioral changes are believed to precede changes in...
Biological invasions provide a unique opportunity to study the mechanisms that regulate community composition and ecosystem function. Invasive species that are also ecosystem engineers can substantially alter physical features in an environment, and this can lead to cascading effects on the biological community. Aquatic-terrestrial interface ecosystems are excellent systems to...
Body size explains much of the interspecific variation in the physiology, behavior, and morphology of birds, such as metabolic rate, diet selection, intake rate, gut size, and bill size. Based on mass-specific metabolic requirements and relative energetic costs of activities, being a certain body size has both advantages and disadvantages....
Narratives are central to communication and the human experience. For a computer system to understand a narrative, it must be able to identify the key facts or plot elements that describe what happened or how the world has changed. These element are called events;establishing a document’s events and the relationships...
The environmental movement needs people from communities of color and the differing perspectives they provide. Latinas/os are one of the largest communities of color in the US, and their numbers continue to grow. However, mainstream environmental organizations have failed to engage this community in authentic ways. The lack of meaningful...
Habitat loss causes a reduction in available resources for wildlife, alters the configuration of remaining habitat, and may isolate wildlife populations. White-breasted nuthatches (Sitta carolinensis) are experiencing long-term population declines in the Willamette Valley of Oregon, where they are historically associated with oak woodlands. As secondary cavity-nesters, white-breasted nuthatches may...
Yeast culture supplementation has been used to improve the health and performance of dairy cows for the last 25 years. To evaluate the effect of a Saccharomyces cerevisiae fermentation product (Diamond V Original XP™) on the health and production of peripartal Holstein cows, two research studies were conducted.
The first...
