21978 research outputs found
Sort by
Early Life History Responses to Varying Hydrological Regimes in Two Endangered Vernal Pool Species
Full text link
Annual plants often rely on specific environmental cues to regulate germination and early growth during a narrow time window each year. In wetland ecosystems, hydrological dynamics often provide important cues for life stage transitions as it influences seed dormancy, germination timing, and seedling establishment. Vernal pools in California experience seasonal flooding and drying, which create unique selective pressures on species adapted to these habitats. Lasthenia burkei and Lasthenia conjugens, two endangered California winter annual wildflowers, are endemic to these seasonal wetlands. Using a controlled greenhouse experiment, I manipulated hydrological patterns to evaluate the potential effects of flooding conditions on germination and early development for both species. I found that flooding led to earlier germination phenology and increased rate of seed germination in L. burkei, but reduced the rate of growth post-germination compared to seeds that were not initially flooded in both species. Furthermore, L. burkei germination was more sensitive to flooding than L. conjugens, while L. conjugens showed evidence of population differences that were absent in L. burkei. These results are vital in understanding the drivers of life history variation in two endangered species and provide useful information for restoration plans that involve introducing seeds into created or restored vernal pool habitats. </p
Understanding the Other: Increasing Empathy through Literature and Language
Full text linkThe divisions between different populations within the US are socially constructed and perpetuated through intergroup interactions, cultural narratives, and media representation. These divisions contribute to the dehumanization of the ‘other,’ a process that facilitates the justification of violence, systemic inequity, and social exclusion. When individuals perceive members of out-groups as fundamentally different or less human, any sense of shared humanity is eroded, making discrimination and harm more acceptable. However, empathy serves as a powerful counterforce to these divisive tendencies. As an adaptable and practicable cognitive and emotional process, empathy fosters understanding and reduces inner and outer group hostility. To effectively combat violence and social fragmentation, empathy must be cultivated and extended beyond familiar in-groups to encompass those perceived as "other." One of the most compelling avenues for empathy-building is engagement with literature and language. Reading and language learning encourage perspective-taking, allowing individuals to step into the experiences of others, while also activating neural mechanisms associated with empathy. By fostering deeper emotional and intellectual connections between diverse groups, literature and language serve as critical tools in dismantling social barriers and promoting a more inclusive and equitable society. This thesis examines how, specifically, literature and language increase empathy, by analyzing interview data and literary works. While my interview sample is limited in scope, data suggest that storytelling and language learning possess a transformative power—one that can reshape perceptions, humanize the unfamiliar, and ultimately contribute to a more empathetic and connected society.</p
Expanded Research into the Relationship Between Solar Flare Magnitude and Doppler Velocities of Solar Plasma
Full text linkThe Doppler Velocities of nominal emission lines during solar flares directly correspond to the solar plasma’s velocity. Understanding potential relationships between these emission lines and solar flares is essential for refining plasma models. The EVE instrument, with its spectral resolution of 0.1 nm, enables the measurement of Doppler shifts in solar ions, allowing for the derivation of Doppler Velocities.
In this thesis, five of the seventy nominal emission lines designated by the EVE science team are analyzed in detail. An overview of the instrument’s measurements and their relevance to the central research question is also provided. Furthermore, the Doppler Velocities for the selected lines are derived. Through graphical modeling and correlation analysis, this study investigates the existence of a relationship between solar flare size and the corresponding Doppler Velocity magnitude.</p
Analyzing the Effects of Reformulated Gasoline Requirements on Ground-Level Ozone Pollution on the Colorado Front Range
Full text linkAfter classifying Denver as a “severe” nonattainment area, the Environmental Protection Agency (EPA) required Reformulated Gasoline (RFG) to be sold in the Denver Metro/North Front Range area beginning in June 2024 to reduce ozone formation. This paper evaluates the effect of RFG on ground-level ozone using both difference-in-differences and triple difference estimators. Using 8-hour maximum ozone levels from EPA monitors from 2019 to 2024, I compare counties in the nonattainment (treated) area to two control groups: other counties in Colorado and counties in similar cities in the West. Difference-in-differences models estimate that ozone increased somewhat significantly by 2.62-4.65% during the RFG implementation period. However, triple difference specifications estimate a non-significant decrease of 1.52–2.49% in ground-level ozone in the nonattainment area during the same period. This suggests that the effect of RFG was not strong enough to negate increasing ozone trends in the Denver Metro/North Front Range nonattainment area.</p
The Double Edged Sword: The Economic and Environmental Impact of China’s 2018 Imported Plastics Ban on U.S.-Asia Relations
Full text linkThe global waste trade has historically allowed wealthier nations to offload plastic waste to developing countries, exacerbating environmental degradation and economic dependency. Until 2018, China imported nearly half of the world’s plastic waste, primarily from the United States. However, the Operation National Sword policy banned 24 plastic imports into China, triggering a dramatic restructuring of global waste trade flows, with U.S. plastic exports shifting to being processed domestically, but with a rise in Southeast and South Asia exports, particularly Malaysia, India, Vietnam, and Indonesia. This thesis quantitatively analyzes international trade data from 2013 to 2024, revealing that while China and Hong Kong once accounted for 87% of U.S. plastic waste exports in 2010, this figure plummeted to 0% in 2020, forcing waste redirection to alternative destinations, such as Malaysia, Indonesia, Vietnam, and India– although this spike in imports to developing nations was not long-term. This study also cross-analyzes waste import data with air quality trends at key recycling centers in China and Malaysia. Findings indicate that China’s air pollution (PM2.5 levels) declined by 34% from 2014 to 2024, correlating with its sharp reduction in plastic imports; conversely, Malaysia’s PM2.5 pollution increased by 31% during the same period, with a notable spike in 2019 following its peak plastic waste imports. This correlation, while not statistically significant, still suggests that while China’s ban improved its own air quality, the environmental burden of plastic processing was simply transferred elsewhere, a continuation of the neocolonial power dynamics from before.</p
Structural Characterization of Tau Fibrils with N410M Modification: Comparative Analysis of CryoSPARC and RELION in Neurodegenerative Disease Research
Full text link
Neurodegenerative diseases affect approximately 15% of the global population, yet their underlying causes largely remain unknown. A common feature of these disorders, including Alzheimer’s Disease (AD), is the accumulation of misfolded proteins in the brain. One protein that readily forms these aggregates is Tau. Tau is associated with the assembly and stabilization of microtubules, which maintain the structure and function of neurons. Tau exhibits noticeable structural variance due to factors such as fibrillization and post-translational modifications, including glycosylation. Glycosylation, specifically N-glycosylation at the N410 position on Tau, has been shown to be altered in AD brain and not in healthy brain. Our lab has investigated synthetic Tau, N410M, using cryo-electron microscopy (cryo-EM) to determine its structural characteristics. This study provides a comparative analysis of cryo-EM software programs, CryoSPARC and RELION, in obtaining helical reconstructions of N410M, offering insights into the advantages and limitations of each for structural determination.
</div
Development of the Checklist for Assessing Antisocial Resilience in Ecological Systems (CAARES): A Strengths-Based Assessment Tool for Antisocial Youth in Poverty
Full text linkAntisocial Personality Disorder (ASPD) is a severe mental disorder which is associated with criminality and societal harm. ASPD is defined by the violation of the rights of others, impulsivity and thrill seeking, criminality, and a lack of remorse. While ASPD is a psychological construct, it is associated with many societal factors, including poverty. Therefore, conceptualizing and treating ASPD and antisocial behavior from a combined psychological and sociological perspective proves useful from both an assessment and treatment standpoint. Despite the efforts of researchers and clinicians, treatment of ASPD remains challenging and inconsistent. Thus, early intervention may be the most effective way to prevent the harmful effects of ASPD. Many interventions have been developed which focus on preventing or reducing antisocial behavior in youth and typically aim to address risk factors faced by the individual. However, many strength factors that protect against the development of ASPD and antisocial behavior have also been identified. By overlooking the presence and potential of these strength factors, treatment options may be underutilized. The present review identifies key strength factors associated with the development of ASPD among youth in poverty, using Bronfenbrenner’s Bioecological Model, which conceptualizes human development through increasingly larger ecological systems, as an organizing guide. The review contributed to the development of a novel strengths-based assessment tool, the Checklist for Assessing Antisocial Resilience in Ecological Systems (CAARES), the purpose of which is to inform the selection of evidence-based interventions for antisocial youth in poverty. The implementation and potential benefits of the CAARES is illustrated through a series of case vignettes. The CAARES can be used by clinicians to identify strengths at both psychological and societal levels, allowing ASPD and antisocial behavior to be conceptualized and treated through an interdisciplinary lens.</p
The Contingency of Metabolic Pathway Evolution on Pre-existing Enzymes
Full text linkThe evolution of metabolic pathways has provided life an avenue to survive environmental changes and has contributed to the diversity of life present today. Metabolic pathways are responsible for all the energy processing and chemical synthesis and breakdown of compounds in an organism. The evolution of metabolic pathways is currently best characterized through bioinformatic evidence by the patchwork model. The patchwork model describes how the formation of novel metabolic pathways occurs by patching together promiscuous reactions of enzymes. Little is currently known about how the process normally occurs, why some pathways arise and not others, and what dictates the evolutionary trajectory of a novel metabolic pathway. Prior work in the Copley lab created a model system to study metabolic pathway evolution using the synthesis pathway of pyridoxal 5′-phosphate (PLP) in γ-proteobacteria. An essential gene in the pathway, pdxB, was deleted in Escherichia coli, Aliivibrio fischeri, Pseudomonas putida, Acinetobacter baylyi, and Salmonella enterica followed by laboratory evolution in minimal medium. The organisms all evolved to restore PLP synthesis. To understand the differences in PLP synthesis restoration across the organisms, I fully characterized the evolved PLP synthesis pathway in A. fischeri. This provided insight into how the mutations that arose during evolution allowed for PLP synthesis to increase to physiologically relevant levels. In collaboration with other researchers in the Copley lab, I found that organisms can take different routes to restore PLP synthesis dependent on their repertoire of enzymes. To study what factors influenced the evolutionary trajectory of the organisms, I conducted enzymatic assays of an enzyme critical in the restoration of PLP synthesis (3-phosphoglycerate dehydrogenase, SerA) in the majority of studied strains. I revealed significant differences amongst the promiscuous activities of SerA enzymes across organisms and showed that the promiscuous activities of SerA influenced the mechanism for restoration of PLP synthesis. These results provide insight into the process of metabolic pathway evolution and reinforce the contingency of metabolic pathway evolution on pre-existing enzymes.</p
Comparing 2 Behavioral Assays for Appetitive Social Motivation
Full text linkPublications on social motivations have increased steadily in the last decade, but methods that provide quantification of complex social behaviors in rodents remain limited. Historically, motivation has been split into two sequential phases: appetitive seeking followed by consummatory behavior. Using the monogamous prairie vole, I seek to expand the capabilities of the most widely used social choice task, the three-chambered partner preference test, to include measures of appetitive social motivation by requiring focal animals to traverse 7 inch barriers to gain social rewards. This project seeks to gain a better understanding of the appetitive social motivation and its role in the selective motivation phenotype seen in bonded prairie voles. We correlated results from the barrier climbing task with simultaneously tested operant behavior testing, in order to compare learning and queue-associated behaviors to a more innate effort based task. This correlation will allow us to have a deeper understanding of selective motivation as well as give insight into advantages and disadvantages of these behavioral testing paradigms for different avenues of research regarding social motivation. In this study we found that while the operant paradigm is capable of separating the appetitive and consummatory phases of social motivation, only the barrier climbing task showed robust separation of the two with easily observable and significant latency to climb over the barrier to gain social access to the partner vs the novel animal, providing an avenue for future pharmacological manipulations and easily tunable social motivation.</p
The Pope-burning of November 17th, 1677: Public Political Display in Restoration London
Full text linkThis thesis uses the Pope-burning that occurred in London on November 17th, 1677, as a public political performance to analyze the cultural and political facets of Restoration London prior to the Popish Plot and the Exclusion Crisis. This thesis provides an analysis of this specific Pope-burning that has been prior to glossed over in the historiography in favor of the larger ones during the Exclusion Crisis by using several unutilized sources and a few other Pope-burnings. This analysis shows a connection between the possible origins of this Pope-burning and the early stages of the Whig movement. By examining this seemingly strange event, from the political messaging to the involvement of cats, we can gain a better understanding of contemporary Londoners. By looking at some of the key events that were occurring in London in the decades prior, the anti-Catholic and xenophobic traditions present in England, and the pride of the City’s independence are some of the topics that will be used to examine this event. Thereby providing a comprehensive understanding of this specific event in the greater context of the Restoration period.</p
Data sources:
Access Repository Dashboard
Do you manage Open Research Online? Become a CORE Member to access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard! 👇