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Estimated Amounts of Terrestrial Carbon Mobilized and Sequestered by the 1980 Mount St. Helens Eruption, Washington State, USA
No full textVolcanic eruptions significantly influence the geologic carbon cycle by emitting CO2 and mobilizing terrestrial carbon pools. The 1980 Mount St. Helens (MSH) eruption offers a unique case study, triggering a massive landslide that displaced 2.7 km3 of sediment, buried 600 km2 of forest, and disrupted regional carbon dynamics. Pre-eruption terrestrial carbon stocks, including aboveground biomass (AGB), dead biomass (D), and soil organic carbon (S), averaged 209.5 tC/ha. Post-eruption, total carbon density fell to 118.7 tC/ha, driven mainly by a 51% reduction in AGB, modest declines in D, and redistribution of S. Over 36 years, ecosystem recovery increased AGB to 118.7 tC/ha by 2016, consistent within measurement uncertainty with the original levels. However, D and S pools remained lower, as inferred from modeling.
Recovery rates of AGB varied by disturbance zone, with the Standing Dead Forest and Scorched Area zones showing the highest regrowth rates (8.72 and 4.40 tC/ha/year, respectively), which we infer to have benefited from residual structures and minimal soil disruption. Debris avalanche and pyroclastic flow zones recovered more slowly, likely due to sediment instability and soil sterilization. Despite full AGB recovery within error, persistent deficits in modeled D and S resulted in a net carbon loss of 25.2 tC/ha across the study area. Still, modeled fluxes indicated that all zones functioned as net carbon sinks during recovery.
This research illustrates volcanic landscapes\u27 potential transition from initial carbon sources to long-term sinks under suitable conditions. It emphasizes accounting for all carbon pools in post-disturbance assessments and highlights site-specific ecological processes critical for enhancing global carbon models and informing climate mitigation strategies
The Geologic History of the Chehalis Forearc Basin, Washington State, USA
No full textThe Chehalis Basin, in southwest Washington, is one of a series of forearc basins between the Cascade Arc and the Coast Range in the Pacific Northwest. While the Seattle basin to the north, and the Portland-Tualatin basins to the south are both relatively well studied, the geologic evolution of basins in between is poorly constrained. The Chehalis basin is underlain by accreted Eocene oceanic basalt of the Crescent Formation. The basin fill consists of sedimentary rocks and volcanic rocks deposited throughout the Cenozoic. It has undergone N-S shortening driven by transpressional stress from oblique subduction of the Juan de Fuca plate under North America and clockwise rotation of the Oregon forearc block. Local subsidence is driven by deformation on W and NW striking faults that bound and intersect the basin. Quaternary activity on these faults is possible but unconfirmed.
To better constrain the development of the Chehalis Basin, I model three key subsurface horizons: the top of the Eocene Basement, the top of the Oligocene Skookumchuck Formation, and the top of the Neogene Lincoln Creek Formation. Isochore (vertical thickness) maps constrain the Chehalis Basin depocenter (the location of maximum sediment accumulation) during the Eocene (47.6 - 36.8 Ma), the Oligocene (36.8 - 20 Ma), and the Neogene (20 - 0 Ma). Results show a northward migration of the depocenter, which I interpret as a shift in basin deformation from the NW striking Cedar Creek Fault to the E-W striking Doty Fault. Clockwise rotation data in the area indicate the Cedar Creek Fault was preferentially aligned with N-S shortening, through the Eocene, but was deprioritized as the Doty Fault rotated to an E-W orientation by the Neogene. Sediment accumulation rates in the basin decreased drastically over time as late Eocene uplift of the Cascade Arc and Miocene uplift of the Coast Range limited accommodation space and shifted the depositional environment from deep marine to fluvial. Paleogene (~40 - 20 Ma) sediment accumulation rates averaged 196 m/Myr, comparable to the Seattle Basin to the north and Portland-Tualatin Basin to the south. Neogene (~20 - 0 Ma) rates averaged 27 m/Myr, similar to the Portland-Tualatin Basin, but an order of magnitude slower than the Seattle Basin. Due to a relatively steep subduction angle under Oregon and southern Washington, the Coast Range emerged (post ~20 Ma) in proximity to the Cascade magmatic arc, leaving minimal space for basin formation in the forearc. Comparatively, shallow subduction to the north resulted in more separation between the Olympic Mountains and Cascade magmatic arc leading to relatively high sediment accumulation rates in the Seattle Basin during Neogene time
Unsupervised OCT Image Interpolation Using Deformable Registration and generative models
No full textOptical coherence tomography (OCT) images are often acquired as highly anisotropic volumes, where the scanning step is dense along the fast axis but sparse along the slow axis. This affects image analysis, such as image registration for longitudinal alignment. To create more isotropic volumes, bicubic interpolation can be used along the slow axis, but it generally produces blurry features. Registration-based interpolation can reduce blurriness, but often fails to generate realistic OCT images. Deep generative models can sample realistic images, but lack the structural consistency constraints required for interpolation. In this paper, we propose an unsupervised image interpolation method that combines registration-based interpolation with a deep generative model to overcome their individual limitations and improve the structural accuracy and realism of interpolated OCT images. We compare the proposed method with both bicubic and registration-based interpolation on real OCT datasets, and show that it achieves the best interpolation performance
A Quantitative and Analytical Study of Light Atmospheric Hydrocarbons in Remote and Urban Environments
No full textAtmospheric non-methane hydrocarbons (NMHCs) are relevant to both short-term environmental and long-term climate changes. NMHCs are emitted from fossil fuels, and the burning of biomass and biofuels. The global annually averaged lifetime of C2 NMHCs ranges from two months for ethane (C2H6), to two days for ethylene (C2H4). C2H6 is the most abundant NMHC in the atmosphere due to annual emissions of roughly 10–20 Tg (1 Tg = 1012 g), and its relatively long atmospheric lifetime. Multi-decadal trends of atmospheric C2H6 have been used to understand changes in fugitive fossil fuel emissions and the resulting implications for methane (H4) emissions. Prior studies of C2H6 identified a correlation between global C2H6 mole fractions and CH4 growth rate. Since there are relatively few time-series measurements of atmospheric NMHC mole fractions prior to the 1990s, new measurements and analysis of historic trends are restricted to ice core, firn air, or archived air samples. Work presented here contains a three-part study to investigate historic NMHC trends. This study includes analysis of prior datasets, the development of an NMHC analytical system and its application to urban air, and the quantification and analysis of the OHSU-PSU Air Archive-a rare collection of air samples collected at remote locations from 1978-1997.
Analysis of prior datasets includes the presentation of previously unpublished whole air sample measurements of NMHCs collected at approximately weekly intervals from 1982-1987 at six stations spanning the Northern and Southern Hemispheres. Samples originated from remote sites that primarily received Pacific Basin air masses, as determined by back-trajectory analysis. The four alkanes in this dataset, C2H6, C3H8, i- and n-butane (C2H4) had a mean measured mole fraction of (712 ± 22) ppt, (245 ± 13) ppt, (55.2 ± 4.4) ppt, and (87.6 ± 8.7) ppt, respectively. No discernible global secular trend for these NMHCs was found over this five-year period, but significant trends at some individual sites may have been influenced by fugitive fossil emissions in the Northern Hemisphere. A large multi-year enrichment anomaly occurs at all sites that is likely associated with the strong El Niño of 1982-1983, and appears to influence trends observed in the Southern Hemisphere. A comparison of measured and GEOS-Chem simulated C2H6 mole fractions estimated global emissions of (13.4 ± 0.4) Tg/yr. Despite interannual variability, the average global mole fraction determined from these measurements during the five-year span corroborates a multi-decadal decline in NMHCs from the 1980s into the early 2000s, when compared with recent datasets.
The development of an NMHC analytical system was part of a pilot study that included hourly mole fractions of GHGs: CO2, H4, N2O, and select NMHCs: C2H6, C2H4, C3H8, i-C4H10, and n-C4H10. Measurements took place in Portland, Oregon (OR), USA in the summer of 2024. Portland, OR is a medium sized urban center, located approximately 100 km from the Pacific Coast. Analytical systems were fully automated: CO2 was measured using a non-dispersive infrared gas analyzer; H4 and NMHCs were measured using gas chromatographs (GC) equipped with a flame ionization detector; and N2O was measured with a GC equipped with an electron capture detector. The NMHC system used a custom front-end pre-concentration system. NMHCs showed high variability, with C2H6 varying from 1.9 ppb at the beginning of summer to 4.1 ppb by the end of September. Each species had a pronounced diurnal cycle, generally reaching a maximum during 6 AM, and a minimum during 4 PM. Various time periods showed strong enhancements that were most often related to wildfire emissions transported by easterly wind trajectories. A comparison of the atmospheric H4 to C2H6 ratio (MER) outside wildfire events to the MER of regional natural gas samples indicated (37.8 ± 3.2) % of CH4 enhancement in Portland during the summer of 2024 was attributable to natural gas.
The final part of this work includes C2-C4 NMHC mole fraction measurements from the 1978–1997 OHSU-PSU Air Archive, including a rare collection of 154 whole air sampled at Cape Meares, OR, USA (CMO). NMHC mole fraction trends complement previous studies of the CMO archive samples which detailed mole fraction and isotopic composition of H4. Long-term trends of C2H6, C2H4, C3H8, and C4H10 were more variable during the 1980s and relatively stable during the 1990s. Secular trends of each species measured showed a multi-decadal decline of (1.9 ± 0.3) % per year for C2H6, (2.9 ± 0.5) % for C3H8, and approximately 6.7% per year for C2H4 and C4H10. Comparison of overlapping mole fraction measurements from this study with those from the Oregon Graduate Institute (OGI) suggests a 21.5% increase to OGI measured C2H6 to conform with contemporary calibration. Applying this calibration correction to OGI C2H6 increases its previous emission estimates from 13.4 Tg/yr to (16.3 ± 0.9) Tg/yr for 1982-1987
Cultural Shadows: Vampires and the Shifting Fears of the West, A Creative Exploration of Vampire Media and Its Reflection Of Evolving Social Anxieties
No full textCultural Shadows: Vampires and the Shifting Fears of the West is a creative-critical thesis that explores vampire media as a reflection of evolving social anxieties in Western culture. Focusing primarily on film and television, with reference to key literary texts, this study examines how the vampire figure is used to articulate and dramatize recurring societal fears—particularly those surrounding women\u27s sexuality and autonomy, queer identity, and class-based inequality. Through close readings of influential vampire narratives, the thesis demonstrates how these stories mirror cultural tensions and moral panics, transforming the vampire into a symbol of both fear and fascination. Drawing on gender theory, queer theory, and film critique, the research argues that vampire media serves not only as entertainment but also as a powerful commentary on the socio-political concerns of its time. The study highlights how visual and narrative representations of vampires shift in response to changing cultural landscapes, offering insight into the fears that haunt the Western imagination.
This written analysis is accompanied by a creative component: an eight-minute motion graphics video and an original book cover design, intended to make these academic insights accessible to a broader audience. Through a handmade, tactile aesthetic, the visual project invites reflection and conversation, encouraging viewers to reconsider the cultural significance of horror media and its relationship to the real-world experiences that shape it
Unsettling Home: Traces of an Unrepaired Settler-Colonial Past in Redding, California, 1846-1924
No full textThis thesis critically reads primary documents from the settler-colonial past of Redding, California, my hometown. In this paper, I sketch out a series of moments of historical trauma which continue to cry out for repair. Through a series of episodes from the mid-nineteenth through the early-twentieth centuries, I examine how original settler thirst for land wrought a contested hegemony in principally genocidal flows of power between the settler-state and its settler inhabitants and the pre-existing local Indigenous nations and peoples. In the first chapter, I argue for an understanding of the dispossession of the northern valley as genocidal. In the second chapter, I argue that genocide and its resultant settler hegemony are incomplete, contested forces in which slippages provide room for the agency of the oppressed. In the third chapter, I argue that the settler-state and settlers are not monolithic in their oppressions, but that their philanthropic, sympathetic gestures often come too late and are not enough. In the fourth chapter, I argue that these conceptions of the region’s history form a new origin story which provides room for genuine repair through truth and reconciliation. For settler-colonialism is not an event, but a structure, intricately woven into the landscape over generations of historical development
Exploring Vaccine Efficacy and Safety for MS Patients on Immunosuppressant Treatment in Light of the COVID-19 Pandemic
No full textMultiple sclerosis (MS) is a chronic neurodegenerative autoimmune disorder affecting approximately 2.8 million people worldwide. Despite decades of research to understand the molecular mechanisms of MS pathology, little is known about why the neurodegeneration caused by this illness occurs. For this reason, current treatments for MS target two broader aspects of the disease: relapse management and prevention via disease-modifying therapies. These treatments often involve immunosuppressive mechanisms, creating vulnerability to infectious diseases that became particularly concerning during the COVID-19 pandemic. This literature review examines the safety and efficacy of vaccination for MS patients on immunosuppressant therapies, highlighting the novel mRNA vaccines developed for COVID-19 and potential interactions between these vaccines and MS treatments. While mRNA vaccination is generally safe and recommended for MS patients, immunosuppressive therapies can reduce the effectiveness of vaccination, necessitating individualized vaccination timing and improved patient-provider communication. Future research should focus on improving understanding of MS pathology on a molecular level, creating personalized treatment plans, and prioritizing clear communication with patients
DIY Music Career
No full textAs we know, the music industry is changing. Where artists once needed access to extremely expensive gear, we now have access to tech that can create professional quality music at a fraction of the price. And where artists once needed labels to back and distribute their music, we\u27re entering into an age where anyone can upload a song directly to the primary platforms consumers use to listen to music. This has led to an era where songs written and recorded in bedrooms are winning grammys (Billie Eilish). But for all the upsides of anyone being able to make and release music… well… anyone can make and release music. Every day, over 100,000 songs are uploaded to the internet. The question of how do I succeed as an artist? is intimately intertwined with the question how do I stand out from the crowd? . Traditionally, artists had to play a lot of shows to build a fanbase large enough to catch people’s attention. Which is unfortunate for an introvert like myself. However, with the rise of social media, there is now a precedent for artists building full scale careers from the comfort of their homes. This project is an overview of the steps taken to build a DIY music career, including; the process of creating music, mixing and mastering, creating marketing material, creating a post schedule, distribution, and royalty collection
Beyond the Bickering: Examining Event, Victim, and Offender Characteristics for Sibling Abuse Incidents in Oregon
No full textSibling violence (SV) is the most prevalent form of intrafamilial and domestic violence, yet it remains underrecognized and lacks the systematic attention given to other forms of family violence. Often minimized or misclassified as typical sibling rivalry, SV can inflict serious and lasting physical, emotional, and psychological harm on its victims. This study explores the characteristics of sibling violence incidents reported to law enforcement in Oregon between 2016 and 2023, using data from the National Incident-Based Reporting System (NIBRS). Through an analysis of 5,793 single-victim, single-offender incidents, the research examines demographic patterns among victims and offenders, incident dynamics, and typological distinctions between juvenile and adult cases. Findings reveal that most SV incidents involved physical assault, occurred in residential settings, and were perpetrated by male siblings. Juvenile victims were disproportionately represented in sexual offenses, while adult victims experienced more physical assaults. The study also highlights disparities by race and ethnicity and underscores the limitations of current legal and social frameworks in addressing sibling violence. By proposing a detailed typology of SV incidents, this research advocates for a reframing of sibling abuse as a serious public health issue requiring focused policy, legal, and clinical interventions
Small Molecule Inhibitor 3i-1000 Dosed During Bouts of Anoxia Increases Survivability of \u3ci\u3eAustrofundulus limnaeus\u3c/i\u3e Embryos
No full textThe annual killifish Austrofundulus limnaeus possesses exceptional tolerance to prolonged anoxia, offering a unique vertebrate model for investigating cardiac resilience and survival under metabolic stress. This study tested whether inhibition of the GATA4–NKX2-5 transcriptional axis with the small molecule 3i-1000 enhances post-anoxic survival. WS40 embryos were exposed to 50 µM 3i-1000 during anoxia and early aerobic recovery. Outcomes were assessed across two independent experimental cohorts. Treated embryos exhibited higher survivability during reoxygenation: in the October cohort, survival increased from 76.0% in vehicle controls (n = 25) to 91.7% in treated embryos (n = 24); in the November cohort, survival improved from 65.9% (n = 56) to 79.2% (n = 52). No significant differences in heart rate were detected between groups, though violin plot distributions did indicate heterogeneity in physiological responses. Post-anoxic survival can be parsed into three distinct cohorts—hatching, diapause, and arrested—across both experimental and control groups. No treatment-induced differences were observed in developmental timing. Together, these findings support the hypothesis that pharmacological disruption of GATA4-NKX2-5-promoted gene transcription enhances survivability under metabolic stress, though current endpoints remain coarse. Future work should incorporate higher-resolution metrics such as electrocardiography, TUNEL staining, and transcriptomic profiling to more precisely characterize potential cardioprotective mechanisms and improve translational relevance to mammalian systems. This work provides new insight into how modulating conserved transcriptional pathways intersects with natural survival strategies and lays the groundwork for future exploration of cardiac regeneration in anoxia-tolerant vertebrates