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The role of pubertal hormones on female rats\u27 sensitivity to acute ketamine treatment in an early-life-adversity model
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Eroding the Bedrock: The Future of Public Administration Without \u3ci\u3eChevron\u3c/i\u3e Deference
Full text linkWhen Congress passes a bill, it produces words on a page. Who decides what those words mean? Historically, the onus of a statute’s interpretation has rested with the federal agencies charged with its implementation. The Chevron doctrine, a two-step standard that affords federal agencies significant latitude in interpreting their own enabling legislation, has been the applicable deference regime in statutory interpretation cases since 1984. Contrary to this tradition, recent Supreme Court jurisprudence has reasserted the primacy of the judiciary in statutory interpretation cases, often ignoring Chevron entirely. In 2023, the Court granted certiorari to Loper Bright Enterprises v. Raimondo, a case that explicitly asked the Court to consider overruling Chevron vs. NRDC, a foundational case in the field of administrative law. This thesis explores the implications of eroding deference to federal agencies through a case study of the Food and Drug Administration and two of its responsibilities. Ultimately, there are potentially negative consequences to limiting agency jurisdiction via eviscerating judicial deference that counsel a more discerning approach
East End Eden: The Gentrification of Portland’s Munjoy Hill
Full text linkThis thesis explores the gentrification of Munjoy Hill, a neighborhood on the northeast end of Portland, Maine from 1990-2024. Once the industrial hub of the city filled with factories and an industrial shipping port in the late 1800s and early 1900s, Munjoy Hill is now the most desirable neighborhood in the city with expensive, high-end condos, water views, ocean access, and hip restaurants and breweries. I argue that Munjoy Hill’s industrial past and strong connection to the local environment has made it unique, however the recent gentrification also makes Munjoy Hill a place that resembles, gentrified neighborhoods in cities around the country. This thesis studies Munjoy Hill’s change through three lenses: environment, housing, and food and drink. In the environment chapter I argue that the Hill’s natural beauty and connection to Maine’s scenic coastline primed it for gentrification once the area deindustrialized in the 1990s. In the housing chapter I explore the dramatic increase in housing prices and three ways residents are attempting to control the changes: affordable housing development, zoning, and historic designation. In my final chapter I analyze the role of new food establishments in transforming the Hill’s culture and cementing it as a neighborhood that feels, in part, like gentrified neighborhoods around the country
Three-Year-Old Agents of Social Change: How aeioTU Educators Build on Children’s Agency
Full text linkaeioTU is a Colombian organization that works to enact social change through the field of early childhood education. In collaboration with the Colombian government, aeioTU oversees several public centers located in socioeconomically vulnerable municipalities in Colombia. This thesis analyzes the aeioTU curriculum and the practices of several aeioTU teachers through the theoretical lens of Freire’s critical pedagogy. This thesis argues that by fostering critical awareness of the world from an early age, as well as by collaborating closely with mothers and the communities at large, aeioTU teachers equip children with the tools to become social agents who can challenge and positively change their lived realities. The research presented in this thesis affirms the potential of aeioTU teachers to enact social change in socioeconomically vulnerable communities by building on young children’s social agency
Neural compensation in response to salinity perturbation in the cardiac ganglion of the American lobster, \u3ci\u3eHomarus americanus\u3c/i\u3e
Full text linkCentral pattern generator (CPG) networks produce the rhythmic motor patterns that underlie critical behaviors such as breathing, walking, and heartbeat. The fidelity of these neural circuits in response to fluctuations in environmental conditions is essential for organismal survival. The specific ion channel profile of a neuron dictates its electrophysiological phenotype and is under homeostatic control, as channel proteins are constantly turning over in the membrane in response to internal and external stimuli. Neuronal function depends on ion channels and biophysical processes that are sensitive to external variables such as temperature, pH, and salinity. Nonetheless, the nervous system of the American lobster (Homarus americanus) is robust to global perturbations in these variables.
The cardiac ganglion (CG), the CPG that controls the rhythmic activation of the heart in the lobster, has been shown to maintain function across a relatively wide, ecologically-relevant range of saline concentrations in the short-term. This study investigates whether individual neurons of the CG sense and compensate for long-term changes in extracellular ion concentration by controlling their ion channel mRNA abundances. To do this, I bathed the isolated CG in either 0.75x, 1.5x, or 1x (physiological) saline concentrations for 24 h. I then dissected out individual CG motor neurons, the pacemaker neurons, and sections of axonal projections and used single-cell RT-qPCR to measure relative mRNA abundances of several species of ion channels in these cells.
I found that the CG maintained stable output with 24 h exposure to altered saline concentrations (0.75x and 1.5x), and that this stability may indeed be enabled by changes in mRNA abundances and correlated channel relationships
Modulation of the crustacean cardiac neuromuscular system by the SLY neuropeptide family
Full text linkCentral pattern generators (CPGs) are neuronal networks that produce rhythmic motor output in the absence of sensory stimuli. Invertebrate CPGs are valuable models of neural circuit dynamics and neuromodulation because they continue to generate fictive activity in vitro. For example, the cardiac ganglion (CG) of the Jonah crab (Cancer borealis) and American lobster (Homarus americanus) contains nine electrochemically coupled neurons that fire bursts of action potentials to trigger a heartbeat. The CG is modulated by neuropeptides, amines, small molecule transmitters, gases, and mechanosensory feedback pathways that enable flexibility and constrain output. One such modulator, the SLY neuropeptide family, was previously shown to be expressed in hormonal release sites and within the CG itself and has unusual processing features. However, its physiological effect was unknown. Here, I performed dose-response experiments in the crab and lobster whole heart and isolated CG to determine the threshold concentration of SLY neuropeptides to which these systems respond. The crab isoform had strong, excitatory effects in the crab whole heart and weakly modulated the crab CG. The lobster isoform weakly modulated the lobster whole heart and CG. Surprisingly, the crab isoform exerted large, variable effects on the lobster system, which suggests that SLY neuropeptides, their receptors, and their signaling pathways may be evolutionarily conserved across these two species. This research contributes to our understanding of how neural circuits can generate flexible output in response to modulation. It may also offer insight into processes influenced by peptidergic neurotransmission in the nervous systems of other animals, including mammals
Deciphering Policymaking—The Enigma of the 2003 Iraq War
Full text linkThis thesis examines the forces shaping the United States’ decision to initiate the 2003 Iraq War. It argues that while the Bush administration had vested interests in disarming Iraq to eliminate Saddam Hussein’s military threat and to secure stable global oil supplies, the decision-making process leading to the Iraq War was heavily influenced by domestic politics, such as bureaucratic bargaining, CIA intelligence collections, and interest group competition. In addition, individual-level factors, such as top officials’ personal beliefs and psychologies, also shaped the decision to intervene in Iraq. By explaining how strategic, domestic, and personal factors interacted to shape the decision to launch the Iraq War, my study underscores the impact of less obvious micro-level dynamics on international politics and the multi-layered nature of foreign policymaking
The Things We Carried: Effect of Exogenous Government Spending Shocks on Wartime Inflation, Evidence from the U.S. and the World
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Basins of Attraction and Metaoptimization for Particle Swarm Optimization Methods
Full text linkParticle swarm optimization (PSO) is a metaheuristic optimization method that finds near- optima by spawning particles which explore within a given search space while exploiting the best candidate solutions of the swarm. PSO algorithms emulate the behavior of, say, a flock of birds or a school of fish, and encapsulate the randomness that is present in natural processes. In this paper, we discuss different initialization schemes and meta-optimizations for PSO, its performances on various multi-minima functions, and the unique intricacies and obstacles that the method faces when attempting to produce images for basins of attraction, which are the sets of initial points that are mapped to the same minima by the method. This project compares the relative strengths and weaknesses of the Particle Swarm with other optimization methods, namely gradient-descent, in the context of basin mapping and other metrics. It was found that with proper parameterization, PSO can amply explore the search space regardless of initialization. For all functions, the swarm was capable of finding, within some tolerance, the global minimum or minima in fewer than 60 iterations by having sufficiently well chosen parameters and parameterization schemes. The shortcomings of the Particle Swarm method, however, are that its parameters often require fine-tuning for different search spaces to most efficiently optimize and that the swarm cannot produce the analytical minimum. Overall, the PSO is a highly adaptive and computationally efficient method with few initial restraints that can be readily used as the first step of any optimization task
Policy Making, Decision Making, and Advocacy: The U.S. Asylum System Since 9/11
Full text linkImmigration justice advocates and immigration restrictionists alike are unhappy with the way that the U.S. asylum system functions. This project seeks to develop a better understanding of policy changes and the politicized influence of the president and executive authorities over the asylum system since 9/11—in particular, these individuals’ ability to implement their policy preferences through the hiring and instruction of Asylum Officers and Immigration Judges. Through case studies of nonprofit organizations, it identifies the key points in the asylum process where asylum has been restricted, and the ways in which these restrictions can be responded to. On the basis of these factors, this project identifies four key changes, made by Congress, through which the asylum system could be improved: the establishment of an Article I immigration court, encoded testimonial and credibility standards, universal representation, and an end to asylum seeker detention. These changes are asserted to depoliticize the asylum process and to create a stable asylum system in which those that should qualify for asylum do qualify