Digital Commons Network^™

Speciation Of Diaryliodonium Salts In Solution And Their Reactivity Towards N-Nucleophiles (Phthalimide And Amines) And O-Nucleophiles (Phenols And Phenoxide), Souradeep Basu

Dissertations and Theses

Benzenoid rings are prevalent in pharmaceutical drug molecules, agrochemical molecules and even in some polymers used in electronic device. Aryl rings are often installed using metal catalysis, however, metal free arylations are known but limited. Diaryliodonium salts are novel electrophilic arylating agents. Herein, metal free N-arylation of phthalimide and diarylether formation using aryl(TMP)iodonium salts is described.

The structure of diaryliodonium salts has been primarily studied in either the solid state or in-silico. The structure and speciation of diaryliodonium salts in solution is not well explored. In this work evidence of dimer formation of aryl(Mes)iodonium salts in chloroform using …

Helminths Of Thomomys Species (Rodentia: Geomyidae) Of Oregon, Malorri Rene Hughes

Dissertations and Theses

Although often viewed as inconsequential, parasites have significant ecological and evolutionary importance, and studying them can generate knowledge regarding their environments and their hosts. Helminths (intestinal parasites) infecting Western pocket gophers (Thomomys species) in Oregon had been documented based only on morphology prior to this study. Basing parasite identification solely on morphology is problematic because the characteristics used to identify species can be vague or similar, leading to misidentification or obscuring the true biodiversity present. Using molecular markers to verify species present not only is more reliable but also can be informative in terms of the host-parasite association. To …

Linear Nearest Neighbor Flocks With All Distinct Agents, Robert G. Lyons

Dissertations and Theses

This dissertation analyzes the global dynamics of 1-dimensional agent arrays with nearest neighbor linear couplings. The equations of motion are second order linear ODE's with constant coefficients. The novel part of this research is that the couplings are different for each agent. We allow the forces to depend on the relative position and relative velocity (damping terms) of the agents, and the coupling magnitudes differ for each agent. Further, we do not assume that the forces are "Newtonian'" (i.e., the force due to A on B equals minus the force of B on A) as this assumption does not apply …

Intersections Of Masculinity, Culturally Relevant Factors, And Intimate Partner Violence Perpetration Among Asian American Men, Jason Z. Kyler-Yano

Dissertations and Theses

Intimate partner violence (IPV) by men against women is a devastating social problem that is experienced by over a quarter of women in their lifetimes (Tjaden & Thoennes, 2000). IPV in Asian American communities is a prevalent problem that is likely influenced by both patriarchal gender role norms as well as culturally salience factors that are distinct to Asian Americans. Given the influence of norms and values on gendered power dynamics and racial power dynamics in the U.S., it is important to understand the intersections of gender and culture in Asian American men's masculine role norms and IPV perpetration. This …

An Automated Zoom Class Session Analysis Tool To Improve Education, Jack Arlo Cannon Ii

Dissertations and Theses

The recent shift towards remote education has presented new challenges for instructors with respect to teaching evaluation. Students in traditional classrooms send signals to instructors which provide feedback for the effectiveness of a given lecture. Virtual learning environments lack some of these communication channels and require new ways of collecting feedback. This work presents a suite of analysis tools for the virtual instructor. Given the transcript and video files for a Zoom meeting, this tool summarizes student sentiment and speaking characteristics. Sentiment scores are derived using state of the art Natural Language Processing (NLP) models. The video file is used …

A Biomimetic Model For Oxidative Metabolism Of Thiopurine Drugs, Oluyemi Oludare Alo

Dissertations and Theses

Type B hepatotoxicity has been reported for thiopurines, and this has limited their clinical uses. Although a lot of research has been done on thiopurines, the precise mechanism of their hepatotoxicity is still unclear. The results of the in vitro and in vivo experiments aimed at assessing the products of their CYP450-mediated bioactivation have been contradictory. Although it has been theorized that the hepatic toxicity of this class of drug is caused by their bioactivation to electrophilic reactive metabolite (RM) and concomitant protein binding to form immunogenic adducts, resulting in direct cellular dysfunction or an immune response via the formation …

Temperature And Predator Effects On Green Crabs (Carcinus Maenas) And Their Distribution In South Slough National Estuarine Research Reserve, Elissa Connolly-Randazzo

Dissertations and Theses

The invasive green crab (Carcinus maenas) has increased in abundance and distribution among Oregon's estuaries. Its global success in establishing in new environments and tolerance for abiotic stressors, such as temperature, raises concern for C. maenas to negatively influence native crab species, especially given global climate change. To improve in predicting invasion impacts, this work analyzed the results from a controlled tank experiment at Portland State University and the field data on a population of C. maenas in South Slough National Estuarine Research Reserve (SSNERR). The aquarium experiment documented predation pressure on C. maenas across a range of …

The Impact Of New Light Rail Service On Employment Growth In Portland, Oregon, Lahar Santra

Dissertations and Theses

This study quantitatively examines the impact of the new Light Rail Transit (LRT) service on employment growth in retail, knowledge, and service sectors before and after opening the LRT. At the corridor level, this study conducts a case study of Greenline in Southeast Portland, Oregon. The results of the corridor level study suggest that the new LRT service increased employment along the Greenline corridor among all the three sectors of interest- retail, knowledge, service in the long-term (ten years) while having slightly different results for the short-term (five years), likely due to the slow growth of LRT benefits. This study …

Effects Of Green Crab (Carcinus Maenas) Across Variable Densities Of Eelgrass (Zostera Marina), Kimberly Alexis Brown

Dissertations and Theses

Eelgrass (Zostera marina) plays a critical role in estuarine ecosystem function by sustaining a variety of marine and freshwater species, but it's increasingly threatened by the aggressive non-native green crab (Carcinus maenas). The abundance of C. maenas is on the rise within the coastal environment of Oregon and it is imperative to know how these populations will affect the long-term health of Z. marina. C. maenas have been linked to declines in Z. marina coverage and shellfish abundance, but there has been no research on to what extent the density of Z. marina affects its …

Spatial And Seasonal Variations Of Microplastic Concentrations In Portland's Freshwater Ecosystems, Rebecca Talbot

Dissertations and Theses

Microplastics are a pollutant of growing concern and are ubiquitous in a variety of environmental compartments. The majority of microplastics research to date has been conducted in marine waters, and less is known regarding the sources and delivery pathways of microplastics in urban rivers. The first chapter is comprised of a review of the scientific literature regarding the spatial and temporal factors affecting global freshwater microplastic distributions and abundances. Microplastic spatial distributions are heavily influenced by anthropogenic factors, with higher concentrations reported in regions characterized by urban land cover, high population density, and wastewater treatment plant effluent. Temporal variables of …

The New Shiny Penny? Regenerative Agriculture Beliefs And Practices Among Portland's Urban Agriculturalists, Melia Ann Chase

Dissertations and Theses

Regenerative agriculture (RA) is a set of farming and land management practices intended to support or enhance soil health and carbon sequestration potential of soils while producing food, fiber, or other agricultural products. It has received broad acclaim from scholars, corporations, and governmental bodies as a potential means of sequestering carbon and mitigating climate change impacts. It has also received critique and pushback for its vague definition, shifting metrics, and lack of acknowledgement of the Indigenous practices underlying the modern suite of regenerative practices. The purpose of this research is to investigate the beliefs Portland, Oregon urban agricultural practitioners hold …

Materials And Methodologies For Spectroscopic And Optical Analytical Applications In Cultural Heritage Conservation Science, Lyndsay Nichole Kissell

Dissertations and Theses

The field of conservation science falls in the intersection of science and art. The work of conservation scientists may include any single subdiscipline of chemistry, though it is most commonly a highly interdisciplinary field taking skills from analytical, organic, and inorganic chemistry, as well as surface and materials science. The aims of conservation scientists are to answer questions about the production and aging of material cultural heritage. Knowing the materials used by an artist can lead to insight about the intentions of the object and knowing how those materials degrade will enable the use of preventative measures to ensure the …

Inverse Modeling Of Atmospheric Ch4 And Δ13C-Ch4 Measurements From Surface Observation Sites To Understand Trends In Global Methane Emissions Over More Than Three Decades, Sayantani Karmakar

Dissertations and Theses

Methane (CH₄) is the second most important greenhouse gas with a radiative forcing of 0.97 W/m² including both direct and indirect effects and a global warming potential of 28 over a 100-year time horizon. Unlike CO₂ whose rate of growth in the atmosphere has remained positive and increased in recent decades, the behavior of atmospheric methane is considerably more complex and is much less understood on account of the spatiotemporal variability of its emissions which include biogenic (e.g., wetlands, ruminants, rice agriculture), thermogenic (fossil fuels), and pyrogenic (i.e., biomass burning) sources. After sustained growth during most …

Random Lasing In Nano-Crystalline Zinc-Oxide Films, Benito Reynaldo Resendiz

Dissertations and Theses

In this thesis, we explore the preparation of random lasers (RLs) using solution-deposited, randomly packed nano-particle films of zinc oxide (ZnO) impregnated with silicon dioxide (SiO₂) nanospheres. RLs have their scatterers randomly oriented, while their lasing comes from light propagating along closed paths through the scattering environment. It is shown here that random lasing is readily observed in films made of submicron sized ZnO particles. Adding transparent SiO₂ nanospheres to the films, we show there is an effective improvement of the lasing that is observable in all of the samples spectra. Specifically, we found that the lasing …

Heat, Wildfire And Energy Demand: An Examination Of Residential Buildings And Community Equity, Chrissi Argyro Antonopoulos

Dissertations and Theses

Extreme heat and wildfire events are becoming more prolific and exacerbated by climate change, carrying significant implications for environmental and social systems. Residential buildings play a central role in protecting people from heat and pollutant exposure during extreme weather events, but the level of protection varies dramatically depending on building energy efficiency and technology availability. Low-income and communities of color have higher energy burdens compared to affluent populations, and underserved communities often do not have financial resources for, or access to, advanced building technologies. This dissertation explores the impacts of extreme heat and wildfire on residential buildings, focused specifically on …

More Than Words: Articulating The Multisensory Experiences Of Protected Area Visitors In Southern Nevada, Sara Nicole Temme

Dissertations and Theses

The complex sensory experiences of visitors to U.S. protected areas are not well understood. Previous research investigates visitor activities, motivations, and the ways place attachment cultivates support for conservation activities and other pro-environmental behavior. However, it is unclear how protected area visitor sensory experiences contribute to these behaviors. This study aims to articulate the multisensory experiences of visitors to the Desert National Wildlife Refuge Complex and the Spring Mountains National Recreation Area in southern Nevada, U.S.A. Specifically, it demonstrates the complexity of these experiences as present, intertwined, and embodied in all visit phases: before, during, and after. Utilizing a mixed-method …

Geographies Of Urban Unsafety: Homeless Women, Mental Maps, And Isolation, Jan Radle Roberson

Dissertations and Theses

This study explores the intersection of urban unsafety and the marginalized population of homeless women. Specifically, it investigates how homeless women identify/perceive and navigate unsafe urban space. Specific research questions include:

1. What does housing insecurity look like for an unhoused woman?

2. In what ways is mental mapping a robust tool for gathering the stories (data) of vulnerable populations such as unhoused women?

3. What does the spatialization of unsafe locations look like and are demographic groupings dissimilarly affected?

4. What are the critical reasons for unsafety identified by participants?

5. How do homeless women respond to urban unsafety; …

Measuring Morality In The 2020 Us Presidential Election, Scott Edward Atkins

Dissertations and Theses

This study explores the moral content evident in speeches by 2020 US Presidential Candidates Joe Biden and Donald Trump. Drawing on Moral Foundations Theory (Haidt, 2013), I test the hypotheses that each candidate's moral content, as measured by the use of certain morally salient keywords, will fall along patterns based on their political affiliation. In testing these hypotheses, I also present a comparison of keyword analysis methods. The first uses a simple word count procedure alongside the Moral Foundations Dictionary 2.0, developed by Frimer et al. (2017), which scores a document based on the presence of words from each of …

Use Of Threat Assessment In South Dakota Schools, Damon Alvey

Dissertations and Theses

Student safety is a priority of administrators today and schools use a variety of threat assessment protocols to reduce potential violence in schools. Risk factors and crisis planning are essential components in building effective school safety plans. Research on mass school shootings identifies practices that when used appropriately may serve as a warning for future acts of violence. This descriptive quantitative study examined South Dakota school superintendents’ perceptions of threat assessment. This study also sought to identify barriers to effective threat assessments. The results of this research study show that superintendents in South Dakota view threat assessments as important. Superintendents …

The Impact Of Using Pow+ Tree With High School Students With Adhd: Story Writing And Perceptions, Katie Page Kroeze

Dissertations and Theses

Only limited research has been completed that examines the impact of teaching outlining on improving ADHD students’ writing skills and perceptions about writing. An abundance of research demonstrates high school students with ADHD struggle with writing and organization skills. This study investigated the impact of using the POW + TREE outlining strategy on high school students with ADHD preparing a composition and how using this strategy impacted a high school student with ADHD’s perception of writing. To answer the first research question, high school students with ADHD were given the task to write an Opinion Story without the use of …

Risk Factors For Traumatic Bonding And Associations With Ptsd Symptoms, Emma Virginia Shaughnessy

Dissertations and Theses

What could lead individuals to become attached to people who cause them harm? Traumatic bonding, a construct similar to, yet distinct from, Stockholm syndrome, offers one possible psychological explanation as to why many people with abusive romantic partners do not break off these relationships. But the question remains: when comparing individuals with abusive romantic partners, what individual-level factors make some of these people more likely than others to develop traumatic bonding toward their current partners? A path model tested the associations among childhood maltreatment, attachment insecurity, traumatic bonding, and PTSD symptoms in a sample of 354 participants in abusive relationships. …

Investigation Of Nuclear Envelope-Associated Progeria Proteins During Nuclear Envelope Rupture, Rhiannon Marie Sears

Dissertations and Theses

The nuclear envelope (NE) is a specialized extension of the endoplasmic reticulum critical for the proper protection and organization of the genome. This interphase-only structure is host to several proteins and their interacting constituents that have various and diverse cellular roles. Mutations in NE constituents are associated with several human diseases. A subset of these diseases, known as progeria syndromes, are characterized by the premature presentation of physiological aging in a variety of tissues. Mutations in the genes LMNA and BANF1, which encode the A-type lamins and barrier-to-autointegration factor (BAF), can lead to these multisystem progeroid diseases. Though the underlying …

Exosomes Derived From Metastatic Colorectal Cancer Mediate Perineural Invasion: Implications For Therapeutic Intervention, Cole Knoblich

Dissertations and Theses

Colorectal cancer (CRC) is one of the most globally diagnosed cancers and a leading cause of cancer-related mortality. Metastatic CRC (mCRC) significantly impacts patient outcome and diminishes overall survival outcomes. Despite advances in therapeutic treatment, the 5-year survival rate for mCRC is < 20% and several patients fail to have a beneficial response to available treatments. This could be attributed to alternative routes of mCRC in which current treatments are unable to block these routes of cancer spread. One such alternative route involves the spread of cancer along the nerve termed perineural invasion (PNI) which is an independent prognostic factor in CRC. The tumor microenvironment (TME) is comprised of several different cell types that have been investigated for their role in cancer pathogenesis. Several studies have shown that cells of the TME can provide a supportive environment that allows for the growth and spread of cancer. Primary focus has been placed on cancer, stromal, and immune cells in the TME, but the role of neuronal cells in cancer pathogenesis is still unknown. Since cells of the TME can communicate through the secretion of exosomes, cancer-derived exosomes have gained widespread interest for their role in cancer pathogenesis. This study investigated how CRC-derived exosomes prime neuronal cells and contribute to PNI. By utilizing transwell co-culture systems and conditioned media experiments, we were able to determine that CRC cells secrete extracellular vesicles (EVs) that induce neuronal cell differentiation and growth, and inhibit apoptosis. Furthermore, utilization of an exosome inhibitor revealed that blocking exosome production in CRC cells could attenuate these affects. CRC- derived exosomes were collected utilizing a modified-iodixanol gradient technique and further characterization revealed an enriched pool of exosomes in fractions. Furthermore, proteomic analysis showed several proteins contained in CRC-derived exosomes that were involved in neuronal cell differentiation and growth. Lastly, treatment of CRC cells with the pharmacological tool Veratridine (VTD) was able to attenuate neuronal cell differentiation and growth and alter the proteomic profiles found in CRC-derived exosomes. In addition, VTD treatment slowed the spread of CRC along the sciatic nerve of an NIH-III nude mouse model of PNI.

Encouraging Persistence Among Native American Nursing Students By Fostering Cultural Identity Development At A Predominantly White University, Valeriah Rose Bi Eagle

Dissertations and Theses

There has been a calling to promote diversity in the healthcare workforce to alleviate the health problems that currently exist among the Native American population. Minorities are disproportionately represented in the nursing workforce (Beard, 2014), especially Native Americans. Increasing the number of Native American nurses in the healthcare workforce has been found to significantly reduce these health disparities (Eddie, 2018; Eschiti, 2004; Gebbie et al., 2003), supporting the need for more Native American nursing students to graduate from college. There has been little research regarding the implications of cultural identity experienced by Native American nursing college students in higher education …

A Grounded Theory Approach To Rural Care Provider Perspectives Of Disability And Sexual Violence, Blake Elvrum Warner

Dissertations and Theses

Research involving sexual violence among individuals with disabilities is scarce despite a prevalence rate higher than the general population. The perspectives of care providers regarding their experience working with individuals with disabilities who have experienced sexual violence is even less understood. The purpose of the current grounded theory study was to better understand the experience of care providers working with individuals with disabilities who have experienced sexual violence. Care providers of individuals with disabilities were recruited from disability services agencies and interviewed by the primary researcher. There were ten participants from a variety of direct care, ancillary care, and administrative …

Deep Features To Analyze Pulmonary Abnormalities In Chest X-Rays Due To Covid-19, Supriti Ghosh

Dissertations and Theses

Artificial Intelligence (AI) has contributed a lot since the beginning. Healthcare is no exception. Detecting anomaly/abnormality in (bio)medical image is crucial. In this thesis, we aim at detecting/screening pulmonary abnormalities due to Covid-19 in chest X-rays using deep features. We study CheXNet, DenseNet169, ResNet50 and VggNet16 to analyze CXRs to detect the evidence of Covid-19 in this research. CheXNet was primarily designed for radiologist-level pneumonia detection in Chest X-rays (CXRs). We created a benchmark dataset size of 4,716 CXRs (2,358 Covid-19 positive cases and 2,358 non-Covid cases (Healthy and Pneumonia cases)) and with k(=5) fold cross-validation technique, using the DenseNet, …

A Job-Demand Resource Theory And Psychological Flexibility Integrated Model Of Police Officer Burnout, Lucas David Baker

Dissertations and Theses

Police officers encounter stressors as a result of job responsibilities that contribute to high rates of occupational burnout. Defined by three primary components (emotional exhaustion, depersonalization, and professional inefficacy), burnout is associated with health- and work-related problems among officers. In addition, police agencies incur significant costs associated with burnout due to performance decline and turnover. Officer burnout is also a matter of public interest given that burnout is associated with low prosocial behavior and high use of force. As such, research that aims to explore the formation and maintenance of officer burnout may be consequential for the profession and society …

What Is Explainable Ai?: A Focus On Ethical Theory, Casey Wall

Dissertations and Theses

A lack of a standardized set of principles within the computer science community is a major issue that impacts the entire field while also creating a level of mistrust among both practitioners of computer science as well as the public. This statement is particularly true when artificial intelligence(AI) is of concern. To create trust in anything one must show that the method of creation is done in a responsible manner. To standardize a set of principles within the computer science community would be to show that the creation of programs and AI can be done responsibly, though this standardization of …

Psychological Functioning And Community Support In Adolescents Exposed To A School Shooting, Jessica Taylor Kelly

Dissertations and Theses

This study evaluated the impact of community support, specifically the impact of a trauma-related community-led campaign, on high school youth following a school shooting. Adolescents are at risk for the adverse impacts of trauma exposure (Katsiyannis et al., 2018; Rajan et al., 2019; Heleniak et al., 2016; McDermott & Cobham, 2012; McLean et al., 2013; Schonfeld & Demaria, 2020). However, social support from one’s community has been found to protect against the psychological and functional consequences of exposure to trauma (Bal et al., 2003; Cheng et al., 2014; Derivois et al., 2014. The purpose of this study was to assess …

Athletic Training Preceptors’ Experiences Of Professional Socialization, Megan Jane Pilcher

Dissertations and Theses

The purpose of this phenomenological study is to gain an understanding of the professional socialization experiences of preceptors who serve in the same masters-level athletic training program. Professional socialization is a phenomenon that occurs as the individual begins to acquire the skills necessary within a given vocation or profession (Bierema, 2010; Merton et al., 1957). Professional socialization within athletic training occurs when the individual adopts the knowledge, skills, values, roles, and attitudes accepted by the profession (Eason, et al., 2014). Preceptors are critical in the education of athletic training students and therefore this study investigated the lived experiences of preceptors …