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Front Matter

Comparative Civilizations Review

No abstract provided.

Paleolimnology And Diatom Taxonomy From Lake Tanganyika, Sristika Adhikari

All-Inclusive List of Electronic Theses and Dissertations

Lake Tanganyika is one of the world's largest freshwater ecosystems, supporting rich aquatic biodiversity and providing several ecosystem services to surrounding communities. Environmental changes such as rising lake surface temperatures, pollution, and land-use alterations threaten the lake’s sustainability. This research examines spatial and temporal variations in nutrient dynamics and primary productivity of Lake Tanganyika using diatom assemblages from multiple locations. Our findings indicate reduced nutrient levels and longer stratification periods in the lake’s central basin during most of the Common Era, as indicated by a remarkable increase in the relative abundance of long, needle-shaped planktonic Nitzschia species. In the southern …

Closer Than They Appear: Parasocial Relationships, Social Processes, And Emotional Intimacy, Paige Bedore

All-Inclusive List of Electronic Theses and Dissertations

Decades of research have attempted to clarify the mechanisms underlying parasocial relationships, or one-sided relationships. Yet, relatively little empirical attention has been given to the subjective experiences of intimacy that occur in these relationships or to making direct comparisons between social and parasocial relational processes within individuals. The present study aimed to address these gaps and to investigate whether selected variables associated with social relationships similarly predicted parasocial relationship strength. Adult participants identified both a meaningful social relationship target and a parasocial target before completing measures of relationship strength, intimacy, attachment style, and cumulative exposure for each relationship type. Hypotheses …

Defining The Value Of Elective Lumbar Fusion: A Systematic Review Of Existing Methodologies And Framework For The Operative Value Index, Advith Sarikonda, Anthony Chen, Theo S. Biddle, Danyal A. Quraishi, Preston Carey, Arbaz A. Momin, Matthews Lan, Dwight Mitchell Self, Ashmal S. Kabani, Ahilan Sivaganesan

Department of Neurosurgery Faculty Papers

BACKGROUND: Despite wide variation in the outcomes and costs of lumbar fusion, few studies have integrated these domains together within a single metric to assess "value" (outcomes achieved per dollar spent). In this review, we sought to 1) characterize existing metrics of cost-effectiveness for lumbar fusion, 2) evaluate all applications of time-driven activity-based costing (TDABC) in spine surgery, and 3) outline the conceptual foundation for a standardized Operative Value Index (OVI).

METHODS: Two PRISMA-concordant systematic reviews were performed on PubMed and Scopus databases. The first review examined all studies which reported a cost-effectiveness metric for lumbar fusion. The second review …

Parent Emotion Socialization And The Influence On Child Emotion Regulation In A Clinical Sample, Crystal Tracy

All-Inclusive List of Electronic Theses and Dissertations

This study aimed to contribute to existing literature by examining parent emotion socialization (i.e., parent orientation to child emotion) and its influence on child internalizing symptoms. Prior research suggests that parent emotion socialization impacts child emotion regulation and internalizing symptoms; however, there is little research at present focused specifically on the influence of parent orientation to child emotion on child internalizing symptoms through child emotion dysregulation. This study adds to the literature by considering the association between parent orientation to child emotion and internalizing symptoms in a sample of children referred for an ADHD evaluation. Participants included 161 children ages …

Storm Surge And Tides In Convergent Estuaries: The Case Of Extratropical Storm Merbok In Alaska, Steven Dykstra, Stefan Talke, David A. Jay, Matthew Lobo, Silvia Innocenti, Pascal Matte

Civil and Environmental Engineering Faculty Publications and Presentations

Coastal floods are composed of multiple drivers that interact with coastline geometries and are difficult to differentiate. To investigate the effects of basin shapes on storm surge and tides, we study the landfall of ex-Typhoon Merbok in the east Bering Sea, Alaska. Water levels at 34 stations are detided with a new tide wavelet tool, CWT_Multi (Lobo et al., 2024), and the spatial and temporal shifts in tides and surge are interpreted via long-wave theory. Results show nonstationary semiannual trends in tidal constituents due to ice effects and large interannual variability in mean-sea level (20-40 cm). After removing non-stationary tidal …

Charting The Martian Future: Long-Term Space Policy Planning Of Nasa’S Human Spaceflight Program, 1957-1988, Angel J. Peralta

Electronic Theses and Dissertations

From the late 1950s to the early 1990s, NASA’s human spaceflight programs repeatedly encountered political and bureaucratic pressures that prioritized short-term interests over long-term planning. These constraints shaped the development of the Apollo, Space Shuttle, Space Station, and other human spaceflight programs, limiting NASA’s ability to pursue a sustained strategic vision. This thesis traces the evolution of long-term human spaceflight policy through documents and memos produced by advisory committees, research councils, and key individuals during this period. Despite shifting administrations and their respective politics, these sources reveal a consistent goal of human spaceflight ultimately leading beyond Earth to the Moon …

Lessons From The Club Homeschool Capstone: Testing, Data Discipline, And The Computer Science Curriculum, Shane Brown

University Honors Theses

This thesis looks at the CLUB Homeschool Capstone project to argue that Portland State University's Computer Science curriculum should introduce testing and data quality discipline earlier and more intentionally than it does now. As team lead of a seven-person team, I coordinated sprint planning, communicated with the sponsor, and developed custom Discourse plugins that enhanced an existing forum platform instead of creating a separate application database, as requested by the sponsor. The project's requirements document called for a formal testing plan, but our team lacked the practical experience to implement one. This gap became evident through my internships as a …

Ranger Ferdinand Castillo: His Life And Legend, David Carle

Eastern Sierra History Journal

Park Ranger Ferdinand Castillo welcomed visitors to Yosemite National Park from his station at the Tioga Pass gate for 38 years, from 1954 to 1993. The warmth of his greeting, which might include a serenade with his guitar, captivated thousands, a memorable moment. Using hitherto unseen documents and images, David Carle does justice to this public servant.

Managing Inventory In The Supply Chain, Matthew J. Drake

Open Education Materials

Inventory represents a significant investment for most organizations and enables its operations to fulfill customer requirements. Effective inventory management frees critical working capital that the organization can use elsewhere while making sure products and services are available for customers. This book discusses the fundamental concepts of managing inventory within the supply chain and also describes methods for making inventory decisions in a variety of business scenarios.

Evaluating The Motivations Of Participants In Online Equine Extension Courses, Sarah Vos

Department of Animal Science: Dissertations, Theses, and Student Research

Traditional program evaluations emphasize participant demographics, knowledge gain, behavior change, and program impact. However, evaluating participant motivation can provide addition insight into why participants enroll in extension programs and help explain participant engagement and persistence throughout a program. The purpose of this study was to evaluate participant motivation in two online equine extension courses and examine potential relationships between motivation, demographics, and course delivery method, and describe participant engagement in Virtual Horse Judging Camp (VHJC). This cross-sectional study utilized convenience sampling of participants in two online equine extension courses, Horse Adult Leader Training and Educational Resource (HALTER) and VHJC. The …

Iniciativas Transfronterizas Informe De Border Fellows 2025-2026, Elise Free Ma, Tori Luna Ma, Jonathan De Vicente Encarnación Mtro., Yolanda Viridiana Chávez Flores Dra., Korina Odet Cortés Uribe Dra., Jessie Valcin, Cristina Solano Díaz, Etienne Mulumeoderhwa Mufungizi Dr.

Kroc IPJ Research and Resources

El Informe Border Fellows 2025–2026 documenta seis proyectos comunitarios realizados en la región Tijuana–San Diego en el marco del Programa Border Fellows del Kroc Institute for Peace and Justice. Desde la academia, la sociedad civil y el sector público, las y los fellows abordaron retos distintos atravesados por un mismo contexto: el tráfico de armas y la violencia armada contra mujeres y personas LGBTQIA+; la violencia juvenil y el riesgo suicida en una secundaria pública; la discriminación en una preparatoria federal con más de 4,300 estudiantes; la capacidad organizativa y los derechos lingüísticos de comunidades indígenas en Baja California; el …

Cross-Border Initiatives Border Fellow Report 2025-2026, Elise Free Ma, Tori Luna Ma, Jonathan De Vicente Encarnación Ma, Yolanda Viridiana Chávez Flores Phd, Korina Odet Cortés Uribe Edd, Jessie Valcin, Cristina Solano Díaz, Etienne Mulumeoderhwa Mufungizi Phd

Kroc IPJ Research and Resources

The 2025–2026 Border Fellows Report documents six community-led projects carried out across the Tijuana–San Diego region under the Kroc Institute for Peace and Justice's Border Fellows Program. Working in academia, civil society, and the public sector, the fellows addressed distinct challenges shaped by a common context: firearms trafficking and armed violence against women and LGBTQIA+ people; youth violence and suicide risk in a public middle school; discrimination in a federal preparatory school serving more than 4,300 students; the organizational capacity and language rights of Indigenous communities in Baja California; academic accompaniment for Haitian adolescents excluded from formal schooling; and intercultural …

Survival First: How Citizens Prioritize Competing Climate-Health Risk Countermeasures Under Fiscal Constraints, Katsuya Tanaka, Kazuhide Akaishi

Center for Public Service Publications and Reports

When governments must allocate limited resources among competing climate-health countermeasures, citizen risk priorities determine political feasibility—yet whether those priorities translate into fiscal support remains poorly understood. This study develops a hybrid best–worst scaling and contingent valuation framework that integrates individual-level priority parameters into an acceptance model, enabling direct testing of whether preference intensity predicts willingness to pay. Applied to a largesample survey of residents in Yokohama, Japan—a rapidly aging metropolis facing escalating heat emergencies—the analysis reveals three findings. First, citizens exhibit a survival-first hierarchy, decisively prioritizing immediate protective measures over long-term structural interventions, with consensus varying sharply across countermeasure types. …

Staff Education On The Implementation Of An Evidence-Based, Suicide-Risk-Assessment Education Program For Psychiatric Staff, Yemurai Emily Dzikiti

Walden Dissertations and Doctoral Studies

Suicide is a major public health concern, and consistent suicide risk assessment is essential for patient safety in psychiatric settings. This Doctor of Nursing Practice staff education project addressed a knowledge gap in evidence-based suicide risk assessment among psychiatric clinicians in an outpatient mental health setting. The practice-focused question examined whether an evidence-based suicide risk assessment education program would improve clinicians' knowledge from pre- to post-education. The educational intervention consisted of a 60-minute in-person training session on evidence-based suicide risk assessment using the Columbia-Suicide Severity Rating Scale (C-SSRS) and the Suicide Assessment Five-Step Evaluation and Triage (SAFE-T) framework. Ten psychiatric …

August 2026, Office Of Research

Research Update

No abstract provided.

Modulating Linear Frequency Modulated Pulses To Send Communications Data In A Bistatic Sar Scenario, Jarren T. Worthen

All Graduate Theses and Dissertations, Fall 2023 to Present

Synthetic aperture radar (SAR) is the technology that enables the creation of images using radar waves, allowing images to be formed regardless of weather. In bistatic SAR a radar platform uses a radar pulse from a separate platform to form an image. It is important that these radar systems are able to communicate with each other. Rather than wasting energy and space flying with a separate communication system, the radar systems could use the already existing SAR system to send data between each other while still forming SAR images. The work of this thesis is to show how very simple …

Fibrous Protein Biomaterials: Characterization Of Solitary Bee Silk And Cocoons, And Development Of Recombinant Hagfish And Bee Silk Materials, Oran Wasserman

All Graduate Theses and Dissertations, Fall 2023 to Present

This dissertation explores two complementary aspects of fibrous protein biomaterials: the characterization of understudied naturally occurring solitary bee silk and cocoons; and recombinant expression and biomaterial formation of recombinant hagfish intermediate filaments (rHIF) and a single Osmia lignaria Say (Hymenoptera: Megachilidae) silk protein. Some solitary bee species, which make up about 75% of all bee species, spin silk to construct protective cocoons during development. Despite the importance of silk and cocoons to the solitary bees' life history, their properties remain largely unexplored. This dissertation presents a novel method for isolating and testing individual silk fibers without interfering with the development …

Multispecies Weed Detection Using Unmanned Aerial Vehicles And Deep Learning Object Detection Models In Utah Forage Crop Corn Field, Utsav Bhandari

All Graduate Theses and Dissertations, Fall 2023 to Present

Weeds cost global agriculture over $32 billion annually and reduce crop yields by nearly one-third. Current weed control relies heavily on spraying herbicides uniformly across entire fields, leading to herbicide-resistant weeds, environmental harm, and increasing costs for farmers. A smarter approach is detecting weeds from the air and spraying only where they are present. This could dramatically reduce herbicide use while protecting crop yields. This thesis developed a complete system for identifying weeds in corn fields using drone-captured images and artificial intelligence. Working in commercial forage corn fields in Cache Valley, Utah, high-resolution aerial images were collected and used to …

Visualizing The Phase Space Of Two Interacting Spherical Magnets Via Lagrangian Descriptors, Matthew Pontius

All Graduate Theses and Dissertations, Fall 2023 to Present

This thesis studies the motion of one spherical magnet sliding on another fixed spherical magnet. Although the setup is simple, the resulting motion can range from regular and predictable to chaotic as the energy increases. To understand this behavior, mathematical tools are used to visualize how all possible motions are organized in phase space. These methods reveal patterns such as stable regions, repeating motions, and chaotic trajectories. The results show how order and chaos coexist in this system and provide insight into how small changes in the initial conditions can lead to very different outcomes.

Comparing Error Correction Strategies In Discrete Trial Training For Children With Autism, Rachael Litchford

All Graduate Theses and Dissertations, Fall 2023 to Present

Children diagnosed with Autism Spectrum Disorder (ASD) often require structured, evidence-based teaching methods to promote skill acquisition. Discrete Trial Training (DTT) is one such approach widely used in Applied Behavior Analysis (ABA) to teach skills through repeated learning opportunities. However, limited research has compared the efficiency of specific error correction procedures within DTT. This study examined the comparative effectiveness of two error correction strategies, Active Student Response (ASR) and Model-Only, when acquiring tacting skills for children ages 2-10 with ASD. An alternating treatments design (ATD) was used to evaluate each strategy’s impact on skill acquisition, as measured by the percentage …

The Influence Of Shape Complexity And Exploratory Behavior On Grasping, Mckenzie Gunter

Dissertations

People can orient and configure their hands in many ways in order to grasp objects. The current study investigates how object shape and hand placement influence graspability of objects, and how experimentally imposed constraints on grasping type alter grasping behavior. In a recent study, Gunter and Hajnal (under review) found that the ratio of object curvature and maximal handspan is the variable that defines the affordance of graspability. The current study aims to extend these findings by employing a more precise measurement of finger placement in two experiments using 3D printed objects as stimuli. To capture varying complexities of object …

Vulnerability In The Dark Triad: Insecure Attachment And Relational Aggression In The Peer Relationships Of College Students, Summer Boggs

Dissertations

Research on relational aggression (i.e., a type of aggression in which the aggressor harms others by damaging their relationships, reputation, and/or feelings of social acceptance) with college students has identified several important correlates, including anxious and avoidant attachment styles. Moreover, the personality traits captured by the Vulnerable Dark Triad (VDT; i.e., borderline, the antisocial component of psychopathy, and vulnerable narcissism; Miller et al., 2010) have demonstrated positive relationships with both relational aggression and insecure attachment. This study examined the relationship between insecure attachment and relational aggression among college students (N = 560), testing VDT traits as partial mediators of …

Implementation Of Phq-9 To Improve Depression Identification In Icu, Jenny C. Manoly Bsn, Rn

Doctor of Nursing Practice Final Project Abstract

PURPOSE This quality improvement project aimed to improve depression identification by screening 80% of eligible adults admitted to two heart failure intensive care units (ICU) using the Patient Health Questionnaire-9 (PHQ-9).

RESULTS Screening compliance increased from 42.1% to 85% by Week 13, exceeding the project goal. Of 101 patients screened, 16.8% screened positive for depression. Workflow changes, leadership support, and peer engagement improved compliance, though psychiatric referrals remained inconsistent.

BACKGROUND Depression is common among critically ill patients but is frequently underrecognized because ICU care primarily focuses on physiologic stabilization. Existing admission screening was limited to suicide risk assessment, delaying identification …

Impact Of Chronic Stress And Nutrition On Functional Connectivity And Neural Networks In Young Kichwa Children From The Ecuadorian Amazon Rainforest, Matthew L. Cook

All Graduate Theses and Dissertations, Fall 2023 to Present

Early childhood is a critical period for brain development. Positive and negative experiences during this time can have lasting effects on learning, health, and well-being. However, most research on children’s brain development has been conducted in wealthy, industrialized nations, leaving important gaps in our understanding of how children develop in other cultural and environmental contexts.

This study examined brain development in Indigenous Kichwa children living in two rural communities in the Ecuadorian Amazon Rainforest. The goal was to better understand how chronic stress and nutrition may influence a child’s developing brain during early childhood. Children participated in noninvasive brain assessments …

Challenges To Longevity Among Native Americans In The Four Corner States, Ashley Lenarz

All Graduate Theses and Dissertations, Fall 2023 to Present

Previous research has shown that Native Americans within the Four Corners States of the United States experience poor health outcomes and premature mortality. The Four Corners States include Arizona, New Mexico, Colorado, and Utah. Research examining COVID-19 pandemic outcomes has also suggested that Native peoples within the Four Corners States have been especially hard hit with high rates of infection and mortality. Our research seeks to (1) understand how life expectancy trends and differences changed among non-Hispanic Native Americans and Whites in the Four Corners States during the COVID-19 pandemic and (2) examine how much of these trends and differences …

Investigating Recruitment Bottlenecks Of Juvenile Native Fish In The Colorado River Basin, Utah, Anna R. Amidon

All Graduate Theses and Dissertations, Fall 2023 to Present

The first year of life is a vulnerable period for most fish species. Whether young fish survive this early stage determines how many individuals eventually survive and grow into reproductive adults, a process called recruitment. In desert rivers like the Colorado River Basin, native fish evolved alongside extreme natural conditions but now face additional pressure from drought and water storage infrastructure, which alter the shoreline habitats on which young fish depend. Long-lived, migratory native species with complex life cycles are especially vulnerable. We used four decades of monitoring data from the Upper Colorado River Basin to evaluate whether young-of-year (YOY, …

Mindful Classrooms: Teachers Co-Designing And Implementing Mindfulness Interventions, Mary L. Phan

All Graduate Theses and Dissertations, Fall 2023 to Present

Teachers play a critical role in supporting student learning and well-being, yet many experience high levels of stress, burnout, and increasing job demands. Stress can negatively affect teachers’ mental health, job satisfaction, and classroom environments, making it important to identify practical and sustainable ways to support teacher well being. Mindfulness practices, which encourage individuals to focus on the present moment with awareness and acceptance, have shown promise for reducing stress and improving emotional well-being. However, little is known about how mindfulness programs can be adapted to fit the realities of elementary school classrooms and whether teachers can successfully implement these …

The Influence Of Habitat And Individual Specialization On Mountain Lion (Puma Concolor) Hunting Strategy In A Multi-Prey System, Hannah B. Klugman

All Graduate Theses and Dissertations, Fall 2023 to Present

There is a growing recognition that animal species considered generalists (having a broad and varied diet), are actually specialists, a collection of individuals with different preferences and strategies known as specializations. The diet of a specialist depends on the variety and quantity of available food options, and their own ability to take what they need. Mountain lions (Puma concolor) are known for their ability and tendency to hunt large prey, such as elk (Cervus canadensis) and mule deer (Odocoileus hemionus), but despite the fact they overlap with other potential large prey, like feral horses …

Cultural Humility In Motion: A Graduate Student Hybrid Immersion In Self- And Other Awareness Through Dance, Emily Jeanne Slater

All Graduate Theses and Dissertations, Fall 2023 to Present

Universities bring together people from many different backgrounds, identities, and experiences. Yet university spaces often focus on mind-centered and discussion-based learning and overlook how the body plays a role in education. When education ignores the bodily experience of learning, students lose opportunities to reflect, connect, and make meaningful change in their lives and communities. To address this gap, this dissertation designed and implemented a learning experience for graduate students that creates space from them to examine their own assumptions, engage across differences, and share in inclusive practices. The learning experience draws on and advances cultural humility theory, which understands self-awareness, …