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Magma Evolution and Eruptive History of Three Fingered Jack: A Mafic Composite Volcano in the Central High Cascades of Oregon
No full textThe central High Cascades graben in Oregon has been a center for mafic volcanism since its initiation. Three Fingered Jack is one of the larger mafic composite cones in the graben, located 20km south of Mount Jefferson. Three Fingered Jack erupted between 142.1 - 150.8ka, based on Ar40/Ar39 age dates. This study provides stratigraphic, compositional and petrographic evidence to understand the eruptive history of Three Fingered Jack and the processes involved in generating compositionally diverse basaltic andesites here.
The basaltic andesites of Three Fingered Jack show three compositional trends of magma evolution: 1) enrichment, 2) depletion and 3) neutral trends. Based on compositional and petrographic data, we propose two different conceptual models for the petrogenesis of all Three Fingered Jack basaltic andesites. A single-source model proposes that a primitive LKT parent supplied magma that fractionated to produce the depleted basaltic andesites. This parent also supplied magma that underwent repeated fractionation and recharge to produce the enriched basaltic andesites. A two-source model suggests that a primitive LKT parent supplied magma that produced the depleted basaltic andesites. A second, primitive calc-alkaline basaltic parent supplied magma that fractionated to produce the enriched basaltic andesites. Petrographic similarities amongst compositional trends suggest that magma mixing occurred at near constant pressure and under similar H2O conditions.
Three Fingered Jack has produced both enriched and depleted varieties of regionally occurring basaltic andesites. It shows compositional similarities and differences to other vents, acting as a piece in our overall understanding of basaltic andesite volcanism in central Oregon High Cascades
Little Did I Know
No full textChristopher Hollister, co-founder and co-editor-in-chief, reflects on his time with CIL in this farewell editorial
A Capstone Review: Strategic Solutions for a Small Macrame Business
No full textThis essay presents an overview of the Business Capstone project, focusing on a macramé business currently facing a $10,000 debt due to limited marketing and financial management skills. The purpose of the project is to support the business in developing an effective elevator pitch, improving its social media presence, strengthening its financial statements, and enhancing both personal and business financial practices. The essay explores the company\u27s strengths, weaknesses, opportunities, and threats, as well as the team\u27s collaborative approach to addressing these challenges. It outlines the goals established for the company, the strategies selected based on our academic backgrounds and business experience, and the outcomes of these efforts. Additionally, the essay reflects on my personal experience in the capstone course and highlights how prior coursework equipped me to complete the project successfully and efficiently
Decomposition Processes and Insect Indicators in Forensic Investigations
No full textInsects play an essential biological and ecological role in human life, and their predictable relationship with decomposing remains has positioned them as a cornerstone of modern forensic science. Since the early 20th century, forensic entomology has provided critical evidence for estimating the postmortem interval (PMI), relying on patterns of colonization, species succession, and insect developmental timelines. Accurate PMI estimations are vital to medicolegal investigations, influencing the interpretation of biological evidence, guiding resource allocation, and informing determinations of cause and manner of death. However, insect activity is profoundly shaped by environmental and ecological variables, including temperature, humidity, seasonal shifts, and geographic context, all of which can alter species availability and developmental rates. This study examines how these abiotic factors affect insect succession and, consequently, the reliability of PMI estimations across diverse environments. Ultimately, forensic entomology\u27s strength lies in its integration of insect biology, ecology, toxicology, and traditional forensic methodologies. As analytical techniques continue to advance, entomological evidence will remain a scientifically grounded and ethically informed tool for reconstructing death events and strengthening the accuracy of criminal investigations
Exploring Underrepresented STEM Undergraduates\u27 STEM Identity Development: The Role of Social Partners
No full textThis dissertation employs a three-study qualitative design to investigate the role of mentorship and social interaction in the identity development of racial minority undergraduate students in STEM disciplines. Grounded in Communities of Practice theory, this research amplifies student narratives to elucidate the relational and contextual factors that inform science identity, belonging, competence, and persistence in higher education. Study One draws upon interview data from fifteen participants in the BUILD program to analyze the role of recognition, particularly from expert scientists--in students\u27 science identity development. This study aims to understand how racial and ethnic identity intersections influence the processes and impact of mentor recognition. Study Two explores the mentor attributes and practices that shape the science identity trajectories of Latine STEM undergraduates. Utilizing semi-structured interviews with eleven students at an emerging Hispanic-Serving Institution in the Pacific Northwest, this study examines how faculty mentorship facilitates or constrains students\u27 engagement, felt competence, and sense of belonging within scientific communities. Study Three investigates the influence of peer interactions on the persistence of Latine students in STEM fields. Employing the same dataset as Study One, this study extends the Communities of Practice framework to examine how peer networks and practices function as affordances or barriers to identity development and academic continuity. Collectively, these studies aim to generate a student-informed mentor manual that offers empirically grounded recommendations for faculty and institutional programs to enhance mentoring practices. By centering the lived experiences of minority students, this dissertation contributes to a more nuanced understanding of identity development in STEM and advances equity-oriented strategies to support the success of underrepresented populations in higher education
Modeling Effective Shade for Oregon Streams Using Satellite Derived Vegetation Structure Metrics
No full textIn the Pacific Northwest, rising stream temperatures threaten the survival of cold-water species, such as salmonids. The Oregon Department of Environmental Quality (DEQ) regulates stream temperature statewide through Total Maximum Daily Loads (TMDLs). To do this, the DEQ uses stream shade as a surrogate measurement for heat, as stream shade and stream temperature have a well-known strong relationship. This project focused on developing effective shade modeling and monitoring methods that increase the pace and scale of temperature TMDL implementation and tracking in Oregon. Stream shade can be measured in the field and modeled with computer models such as HeatSource, which require canopy height data. DEQ sources this data from airborne LiDAR or hand digitization of aerial photography. However, LiDAR canopy height data is not available in a large portion of the state and can be outdated depending on the location. Additionally, hand digitization of canopy height is time consuming and not practical on a large, repeatable scale. An organization, Planet Labs, developed a proprietary model that provides statewide canopy height estimates at higher temporal frequency and lower cost than LiDAR. This study evaluated the usage of canopy height data derived from satellite imagery for modeling effective shade with the HeatSource model in comparison to LiDAR derived effective shade. The performance of the effective shade values derived from satellite image canopy height data varied across land (Spearman’s Rank Correlation Coefficient (ρ) = 0.57). The highest correspondence was in forested areas (ρ = 0.75) and the lowest in agricultural areas (ρ = 0.15). Canopy structure was the driver behind this pattern, as homogeneous canopy structures had higher correspondence between satellite image and LiDAR derived effective shade, while heterogeneous canopy structures had lower correspondence. Additional field research is needed to evaluate the correspondence between field measured and satellite image derived effective shade because equipment failure precluded the direct comparison. For increasing the pace and scale of field measurements of effective shade, the DEQ plans to add an additional field method, hemispherical photography, which captures 360-degree canopy images to measure and document shade, alongside the current effective shade method, the solar pathfinder. This study evaluated the correspondence between the two field methods. The results of this study show that the two effective shade field methods produced comparable results in streams with moderate to high shade coverage. The DEQ will move forward with adopting hemispherical photography as an approved field method. By improving shade modeling and monitoring processes, this project seeks to aid in accelerating riparian restoration efforts and improve water quality management across Oregon
Framing Narratives About Policy: Character Race Impact on Welfare Support, Stereotypes, and NIMBYism
No full textAs the wealth gap in the US continues to grow, many struggle financially. Resistance to policy intended to provide relief, including NIMBY (not in my backyard) beliefs toward affordable housing, is often linked to racial attitudes. This project utilized an experimental design to investigate whether narrative can be used to overcome resistance in the context of government assistance programs. Black (n = 269) and white (n = 272) adults in the US were recruited with an online survey platform, Prolific. Participants were randomly assigned to one of three conditions (narrative with a Black character, with a white character, or no narrative). As hypothesized, participants who saw a narrative had higher welfare support, lower negative welfare stereotypes, and lower NIMBY attitudes than participants who did not see a narrative. Participants who saw the condition with a white character had significantly higher welfare support, lower negative welfare stereotypes, and lower NIMBY attitudes compared to the control, partially supporting hypotheses. There was no significant difference between the condition with a Black character and other conditions. Predictions regarding causal attribution of poverty and racial perceptions were not supported. Results provide support for the use of narrative as a tool for policy advocacy. Future research should further study the impact of character demographics on audience attitudes
Framework and Methodology for Risk-Based Bridge and Tunnel Asset Management: Risk-Based Asset Ranking and Corridor Prioritization
No full textThis report presents the results of Phase II of the project, Framework and Methodology for Risk-based Bridge and Tunnel Asset Management . The research was carried out at Portland State University in collaboration with engineers and officials at the Oregon Department of Transportation (ODOT) and Federal Highway Administration (FHWA). Using the framework and methodology developed in Phase I of the project, the primary goal of Phase II is to showcase the practical application in risk-based asset management. In particular, the report includes the following two case studies: Case Study I — Weighted hazard scenarios for seismic risk assessment of Oregon Highway Bridges, and Case Study II — Accessibility risk assessment and corridor prioritization for Portland bridge network under a scenario Cascadia Subduction Zone (CSZ) earthquake. Each case study focuses on a specific method proposed in the Phase I of the project
Assessing Older Adult Behavioral Health Diagnoses in Oregon by Geographical Area, Physical Disability Status, and Age.
No full textThis repeated cross-sectional study aims to assess potential differences among behavioral health (BH) diagnoses for older adults. Differences in services across urban versus rural/remote areas may contribute to deeply entrenched barriers to improved BH for this population
Applications of Artificial Intelligence in Dental Malocclusion: A Scoping Review of Recent Advances (2020-2025)
No full textIntroduction:
Dental malocclusion affects more than half of the global population, causing significant functional and esthetic consequences. The integration of artificial intelligence (AI) into orthodontic care for malocclusion has the potential to enhance diagnostic accuracy, treatment planning, and clinical efficiency. However, existing research remains fragmented, and recent advances have not been comprehensively synthesized. This scoping review aimed to map the current landscape of AI applications in dental malocclusion from 2020 to 2025. Methods: The review followed the Joanna Briggs Institute methodology and the PRISMA-ScR guidelines. The authors conducted a systematic search across four databases (PubMed, Scopus, Web of Science, and IEEE Xplore) to identify original, peer-reviewed research applying AI to malocclusion diagnosis, classification, treatment planning, or monitoring. The review screened, selected, and extracted data using predefined criteria. Results: Ninety-five studies met the inclusion criteria. The majority employed convolutional neural networks and deep learning models, particularly for diagnosis and classification tasks. Accuracy rates frequently exceeded 90%, with robust performance in cephalometric landmark detection, skeletal classification, and 3D segmentation. Most studies focused on Angle’s classification, while anterior open bite, crossbite/asymmetry, and soft tissue modeling were comparatively underrepresented. Although model performance was generally high, study limitations included small sample sizes, lack of external validation, and limited demographic diversity. Conclusions: AI offers the potential to support and enhance the diagnosis and management of malocclusion. However, to ensure safe and effective clinical adoption, future research must include reproducible reporting, rigorous external validation across sites/devices, and evaluation in diverse populations and real-world clinical workflows