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Morphology of AGN Host Galaxies During Cosmic Noon With JWST
No full textIn this project, we studied active galactic nuclei (AGN) host galaxies during cosmic noon (z ∼ 2) using data from the Cosmic Evolution Early Release Science (CEERS) Survey with the James Webb Space Telescope (JWST) cross-matched with X-ray luminosity data from the Chandra X-ray Observatory. We modeled the rest 9600Å wavelength morphology using the GALFIT software that fits two models: 1) a single Sérsic component and 2) a two-component model that included a point spread function (PSF) component to better fit the central AGN. We compared the effectiveness of the two models by calculating the residual flux fraction of each galaxy with both models to create a quantitative metric. We found that about 33% were above the cut-off point, which we classified as “heavily improved”. We also calculated an AGN-Host flux ratio for each galaxy using the two-component model values for flux. Using values from our morphological fitting, we found that using a best-fit approach for each galaxy resulted in a more disk-like trend than previously observed with a single-component model, finding a median value of 3.4 for the single-component model and 2.83 for the two-component model. Additionally, we found clear relationships between AGN fraction and X-ray luminosity. Future work on this population of galaxies may include a comparison to SED plots and a broader sample size using other JWST fields matched to known X-ray sources
Shouting Down Democracy: The Role of the Deeply Engaged in American Political Discourse
No full textIn an age of heightened polarization and increasing incivility in politics, a small but influential subset of Americans, known as the deeply engaged have emerged as dominant voices in political dialogue. This thesis investigates who these individuals are, what drives them, and how their behavior impacts democratic participation in the United States. Through a combination of theoretical analysis and original survey data, this study constructs a profile of the deeply engaged and distinguishes them from the general electorate. Drawing on foundational concepts of free speech, including isegoria and parrhesia, and the philosophies of John Stuart Mill and Karl Popper, this work situates the deeply engaged within broader historical and ethical frameworks. Empirical findings suggest that these individuals are typically younger, more educated, Democrat, and more likely to be male and financially secure. They are characterized by high levels of media consumption, frequent public political expression, and a confrontational rhetorical style. Their understanding of free speech often aligns more with parrhesia, which values unrestrained expression even if it means others are unable to share their own views. Their deep engagement can strengthen democracy, but it can also hinder fair debate and social unity. This thesis argues that the deeply engaged differ from other Americans and wield disproportionate influence over public narratives and political culture – an influence that may undermine the egalitarian ideals central to American democracy
Are Cities Still Liberal? An Analysis of Post-Pandemic Political Change in American Cities
No full textThis thesis investigates whether American cities are experiencing a political shift to the right in the wake of the COVID-19 pandemic, as suggested by recent media narratives. Drawing on an original national survey of 2,385 respondents conducted in early 2025, the study examines attitudinal and demographic changes among urban residents, with a particular focus on ideology, trust in local government, economic perceptions, and views on race and immigration. Despite anecdotal evidence of conservative gains in urban elections, the findings show no significant trend toward conservatism among urban residents overall. In fact, urban respondents were slightly more likely than their non-urban counterparts to report becoming more liberal. The thesis also tests competing hypotheses for localized shifts: that urban Democrats are becoming more conservative, that newcomers to cities are ideologically distinct, and that rising diversity may produce backlash consistent with racial threat theory. Across these tests, little evidence supports a broad ideological transformation. However, respondents who reported becoming more conservative expressed stronger support for neoliberal economic ideas, particularly regarding poverty and government regulation. A logistic regression model confirms that these economic beliefs—not race or crime-related concerns—best predict attitudinal shifts. Ultimately, the study concludes that while cities are not becoming more conservative in aggregate, subtle ideological currents—especially related to neoliberalism—are shaping perceptions of change. The paper calls for more longitudinal and policy-specific research to distinguish between actual shifts in voter ideology and changes in urban policy driven by broader structural or partisan forces
Affine Groups: A Functorial Perspective
No full textA familiar construction associated to any commutative ringRwith1is its group of units, traditionally denoted by Rx= {u in R | uv = 1 for some v in R}. This is but one out of many ways to get a group from a ring. To see at least one other way, we need a mild change in perspective: units may instead be characterized as elements for which the linear transformation f(r) = u ⋅ r is an isomorphism of R as a module over itself. That is to say, Rx = GL(1, R). We now have the “first” general linear group over R, so we can keep going: GL(2, R), GL(3, R), GL(4, R)and so on are naturally the 2x2, 3x3, 4x4, etc. matrix groups with invertible determinants. In general, GL(n) is an instance of an affine group. This thesis aims to present the beginnings of the theory behind such objects. To do so, we will take a top-down approach. The first section will introduce the category-theoretic underpinnings of the subject to make sense of the discussion that follows. This section is concluded with the Yoneda lemma and the corresponding embedding. The subsequent section introduces affine groups and Hopf algebras, followed by a discussion of some classic examples of both. Lastly, we will look at the tiniest bit of representation theory of affine groups, culminating with proof that every affine algebraic group over a field embeds into some GL(n)
Why Community: The Potentials and Limitations of Community Engagement in Restorative Justice
No full textThis thesis explores the role of community in restorative justice through both the criminologist and practitioner perspectives. Through investigating the limitations of the U.S. penal system, which ranks highest globally in incarceration rates yet fails to ensure public safety, the research investigates restorative justice as a victim-cantered, harm-driven alternative. It emphasizes how restorative justice redefines crime by focusing on healing and accountability rather than punishment of the criminals/harm-doers. This thesis examines how communities are essential to restorative processes and how restorative justice, in turn, helps to build communities. Drawing from case studies, models, and interviews this thesis questions the assumptions underlying community participation, revealing challenges in defining community, feasibility, and dysfunction, particularly when identity-based divisions or structural inequalities are present. Interviews with practitioners supplement theoretical frameworks, offering insight into the complexities of implementing restorative practices in real-world settings. Finally, the study advocates for clearer definitions, better support mechanisms, and adaptable models that consider the diverse nature of communities. By proposing preliminary solutions and future directions, this thesis contributes to the evolving discourse on how restorative justice can more equitably and effectively serve modern society
Identifying the Spread of Invasive Jumping Worms across Maine’s Forests using Soil eDNA
No full textJumping worms of the Megascolecidae family are invasive earthworms from East Asia that have been spreading across the United States since the late 1800s (Chang et al., 2021). Recently, the earthworms have gained more attention for their expansion into northeastern states, as they are believed to have negative impacts on the soil biogeochemistry, flora, and fauna of these forest ecosystems that have had no native earthworms given the recent nature of the Last Glacial Maximum (~11,000 yrs ago; Bohlen et al. 2004; McCay et al. 2020). The earthworms are distinguished by their thrashing behaviors, milky-white smooth clitellum, and evenly spaced setae (Chang et al. 2016). But, to identify the worms by species, male genital pores are needed, requiring sampling of the worms when they are adults in the late summer and early fall (McCay et al. 2020; Chang et al. 2021). However, detecting the worms by species is also difficult because many individuals have degraded or absent male genital pores, meaning that genetic detection of the earthworms using soil eDNA could be effective in determining species presence quicker and year-round (McCay et al. 2020). While the method shows promise, little research has been done using soil eDNA earthworm identification with jumping worms in the United States, and none have occurred in Maine (Bienert et al. 2012; Kirse et al. 2021; Lilja et al. 2023).
The goal of our study was to identify the spread of jumping worms using soil eDNA metabarcoding across Maine’s forests and to identify any differences in soil chemistry or plant composition between plots with and without detected worms. To answer our research questions, we collected and analyzed soil chemistry, plant composition, and soil eDNA data from 56 plots across 16 sites in protected forests in Maine (arboretums, land trusts, state parks, botanical gardens, public reserved lands). The eDNA was amplified using COI primers and run on gels using Agar Gel Electrophoresis. Bands were isolated, purified, and sequenced using Oxford Nanopore Sequencing. We used Geneious Prime to bioinformatically detect species and R to investigate potential trends.
In the end, we found no jumping worms, but we did find European earthworms in 20 out of the 36 plots where DNA was sequenced. We also found no significant trends between plant composition, soil chemistry, and earthworm detection and species. As an incredibly invasive species that has been seen to alter forest ecosystems and is pushing north, it is vital to continue studying how jumping worms impact northeastern forest ecosystems. Future use of randomized, widespread, long-term genetic data collection on earthworm presence in relationship to ecosystem characteristics could help managers and researchers better understand the impacts of the worms in Maine and where to limit their spread
Asian American Navigation in Higher Education: Do We Belong at Colby College?
No full textThis thesis explores how Asian American students navigate their belonging at Predominantly White Institutions (PWI), specifically a case study at the higher educational institution Colby College. In understanding how Asian American students navigate the spaces around them, this thesis dives into the history of Asian immigration to the U.S., the Asian American politicized label, and the different diasporas and cultural nuances Asian Americans experience that make up the complicated, diverse, and misunderstood label. Through exploring global racializations of Asian bodies and legacies of Western imperialism and colonialism, this gives a basis of how Asian Americans understand themselves as persons living in the U.S. After establishing who Asian Americans are, there is a large focus on the concept of belonging and how Asian American students reposition themselves in different communities (academic, social) to find belonging within the larger institutional community. In this thesis, I argue it is not necessarily being a minoritized identity that influences whether one feels belonging or not in a PWI, but more so if one feels they are a marginalized identity that has greater influence on how they find belonging within the greater community. While this thesis focuses on exploring the nuances and diversities within the Asian American identity and how that fits into belonging at an institution, it is not about defining or encouraging belonging. Rather, this thesis is attempting to further understand the global processes and multiple intersectional identities individuals have that inform how we navigate our positions in historically white higher educational institutions not made for minoritized identities
Global Rate Pass Through: Impact of the Global Savings Market on Home Prices in the UK
No full textThis paper examines how changes in the global savings and investment market impact housing prices and supply in the United Kingdom. I first constructed a global interest rate using principal component analysis. Then, using structural VARs, I estimate impulse response functions to study the dynamics of housing prices and supply in the UK with an impulse in the global interest rate. The model predicts that housing prices and supply will increase immediately and then decrease after a lag. The decrease is primarily driven by the years after the stock market crash as opposed to before
