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NMR Measurements of Intramolecular Hydrogen Bonding in 1,3-Disiloxanediols and 1,6-Diols
No full textMethanol titrations of partially deuterated diols dissolved in non-polar solvents such as CD2Cl2 and C6D6 provide 1H NMR measurements of OH/OD isotope shifts, diagnostic for the presence or absence of intramolecular hydrogen bonds under increasing protic solvent conditions. Understanding how intramolecular OH/OH bonds respond to solvent perturbations is important for advancing models of non-covalent interactions in catalysis. While conformationally rigid 1,3- and 1,4-diols have been extensively studied, the behavior of systems with labile intramolecular hydrogen bonds remains unexplored. A series of 1,6 diols (1-3) were synthesized from 2-adamantanone (4) and structurally confirmed via ¹H NMR and GCMS. These compounds, models for distal hydrogen bonds, were titrated with deuterated methanol to track isotope shifts indicative of relatively weak, non-persistent OH/OH interactions. These 1,6-diols act differently than rigid diols, whose intramolecular OH/OH hydrogen bonds persist in the presence of excess methanol. Specifically, these 1,6-diols exhibit a positive, non-persistent isotope shift mapped alongside the mole ratio of CD3OD/diol. Similar experiments are underway involving 1,3-disiloxanediols for a comparative analysis (7 – 8)
Consciousness Unbound: Ketamine and the Limits of the Global Neuronal Workspace Theory
No full textThis thesis critically evaluates the Global Workspace Theory (GWT) and its neuroscientific extension, the Global Neuronal Workspace Theory (GNWT), by examining how each attempts to explain the mechanisms underlying consciousness. GWT frames consciousness as a functional system that globally broadcasts information across distributed cognitive processes, while GNWT grounds this model with key neural signatures such as long-range frontoparietal connectivity, ignition, and P3 wave formation. Both theories primarily define consciousness in terms of access—the availability of information for verbal report, memory, and voluntary action—while sidestepping the subjective, phenomenal counterpart emphasized in philosophical accounts, particularly those by Ned Block.
Building on the distinction between access and phenomenal consciousness and the challenge posed by Chalmers’ “hard problem,” I argue that treating access as equivalent to consciousness leaves these models empirically vulnerable. By looking at recent studies involving general anesthetic agents—particularly propofol and ketamine—I demonstrate that while both propofol-induced unconsciousness and unresponsiveness align with what GNWT predicts, sub-anesthetic doses of ketamine have led subjects to report vivid, dream-like experiences despite an absence of behavioral responsiveness.
These findings potentially suggest that phenomenal consciousness persists without access consciousness, revealing a central limitation under GNWT’s framework. I argue that this dissociation under ketamine poses a challenge to how theories such as GNWT define and measure consciousness. Ultimately, this thesis aims to bridge philosophy and neuroscience, calling for a more nuanced understanding of conscious experience beyond access-based models, and proposes a “dual-state” brain hypothesis to account for preserved phenomenal content
El impacto de la Influencia Continua del Colonialismo en cómo las Comunidades en Jujuy, Argentina y Amazonas, Brasil Experimentan y Responden a la Violencia contra la Mujer
No full textEl colonialismo es un proceso intrínsecamente discriminatorio y violento. Se basa en la idea de que hay grupos superiores que tienen el derecho de controlar al otro, y esta dominación requiere fuerza. No puede suceder en paz. Mi investigación analiza cómo esta lógica colonial se manifiesta en las sociedades poscoloniales contemporáneas. En concreto, indaga su influencia en cómo las comunidades en Jujuy, Argentina y Amazonas, Brasil experimentan y responden a la violencia contra la mujer. Realicé este trabajo a través de diez entrevistas en profundidad con profesionales que tratan los temas de la violencia contra la mujer o los estudios poscoloniales en Argentina y Brasil. También analicé varios anuncios de servicio público y productos culturales de Jujuy y Amazonas para fortalecer mi perspectiva regional. Desde aquí, saqué las conclusiones siguientes: El programa colonial de dominación y las desigualdades que produce aumenta la prevalencia de la violencia contra la mujer, obstaculiza las redes de apoyo para las víctimas, y disuade a estas mujeres a buscar ayuda. Las mujeres en Jujuy y Amazonas, dos regiones predominantemente originarias, sufren aún más en este contexto poscolonial por la doble opresión que enfrentan por ser una mujer y por ser originaria. Pero, esta discriminación historica también inspira una cultura de resistencia contra las violaciones de los derechos como la violencia contra la mujer que poblaciones han sufrido desde siglos
Improving Energy Intensity in the Automobile Manufacturing Sector
No full textWhile energy usage supports modern life, it is important to recognize that it comes with environmental costs. These costs include pollution impacts, social impacts, and global warming impacts from greenhouse gas emissions. While some of the associated costs are linked to energy use, such as through nonrenewable fuel consumption, many are still attributed to building energy production infrastructure. Considering that energy consumption is not likely to slow down in future years, it is therefore essential to improve energy efficiency in consumption to reduce or avoid building new energy infrastructure. This cannot be managed with broad solutions, but through industry-by-industry analysis, opportunities for improving energy efficiency appear. Through my research, I examine the automobile manufacturing industry and propose methods to reduce energy intensity in car production. This is accomplished through using publicly available information from research papers, corporate sustainability reports, and other datasets. In this thesis, I find that energy efficiency can be improved by substituting materials within passenger vehicles, optimizing the supply chain transportation steps, making specific policy changes, and employing new manufacturing philosophies modeled after lean manufacturing procedures. Although some of the findings are only applicable to the automobile sector, many could be used for the whole industrial manufacturing industry. These recommendations would allow for continued development and expansion while reducing the incremental energy requirements, with the aim of stopping further total energy consumption completely
GaloisTheory and the Arithmetic-Geometric Series
Get PDFMotivated by classical works of Gauss and Euler on the AGM, Ono and his
collaborators Griffin et al. (2023); McSpirit and Ono (2023) have investigated
the union of AGM sequences over finite fields , where ≡3 mod 4. A
recent preprint Kayath et al. (2024) extends some of their results to all finite
fields with odd characteristic. We refine these works when ≡5 mod 8. In
particular, we explicitly determine the components of these graphs and their
total population. We also use Galois-theoretic results to make progress in
the search for cycles over finite fields with odd characteristic
Accounting Metrics and Stock Sensitivity: A Comparative Analysis between Small Cap and Large Cap Companies
Get PDFThis study examines whether the cumulative abnormal returns (CARs) of small-cap companies are more sensitive to accounting metrics such as return on assets (ROA), return on investment (ROI), return on equity (ROE), and the debt-to-equity (D/E) ratio compared to large-cap companies. Using a sample of firms from the S&P 500 and S&P 600, moderated linear regression models were applied to test the relationship between profitability, leverage, and stock price reactions. The models include interaction terms with firm size and control for time-fixed effects. The results show that while profitability metrics are positively and significantly associated with CARs for large-cap firms, small-cap firms exhibit weaker sensitivity, and the D/E ratio has no significant effect for either group. Overall, accounting metrics explain only a small portion of variation in CARs, suggesting that other factors such as analyst coverage and broader market conditions play a larger role in influencing investor responses
Pacification in Rio de Janeiro Comunidades: Perceptions of Militarized Public Security
Get PDFBrazil’s history of militarization in public policy has led to the adoption of new models centered around crime intervention and community growth. Rio de Janeiro’s 2008 Comunidade (Favela) Pacification Program was one of the most notable policies reflective of these goals. Rio’s state government implemented Pacifying Police Units (UPPs) that would be permanently stationed in comunidades, driving out criminal organizations and promoting socioeconomic development.
The program was recognized as a symbol of reform in urban security thanks to initial crime reductions in pacified communities. However, testimonies reveal patterns of physical and institutional violence at the hands of UPPs and continued control through militarization. This thesis examines how narratives challenge the perceived successes of the Pacification Program and the broader concept of militarized public security.
Using empirical data that shows changes in different crime rates, both violent and nonviolent, I examine the short-term outcomes of the policy. In tandem with this, through the use of testimonial accounts, this project explores the gaps between official portrayals of the UPPs and lived experiences on-the-ground. I find that during its most active years (2008-2018), the policy led to drops in crime that were acclaimed as successes, but were unsustainable and lacked social integration strategies. Through strict policing methods, the UPPs ultimately contributed to the intensification of order through militarized control, furthering a culture of distrust between police and civilians
An Associative Account of Political Obligation and Its Implications for Global Justice
Get PDFIn this thesis I explore a theory of political obligation and justice described by Thomas Nagel, and examine the implications of his account for the demands of global justice. I begin by defining political obligation and outlining three families of morally relevant duties, voluntary duties, associative duties, and general duties, and explain how political obligation can be thought of as each type of duty. I claim that political obligation is best thought of as an associative duty, and present an associative account of political obligation and justice articulated by Nagel. After analyzing Nagel’s account, I suggest that an adherence to his theory of justice may justify global demands for justice. In particular, using analysis from Olúfẹ́mi Táíwò I suggest that the extreme level of global interdependence makes the rules of global institutions coercively imposed, and justifies subjects of those rules in demanding that those rules treat them fairly. Next, I consider how demands for global justice grounded in an associative approach differ from those grounded in a general duties approach. Finally, I argue that the associative approach offers a richer and more acceptable justification for why demands of justice are global
Faltered States: The Rise, Fall, and Containment of Psychedelic Science in the United States
Get PDFThis thesis traces the history of psychedelic science in the United States and its implications for policymaking. In the postwar period, psychedelic researchers were enabled by a unique convergence of optimism in medical science and structural flexibility. But their hope blinded them to the deeper tensions of their field. As institutions grew increasingly rigid and risk-averse, the space for psychedelics began to close. Some scientists responded by fortifying the walls around them, developing socially and professionally acceptable research methods. Others tried to escape these walls entirely. But neither approach could prevent psychedelics from being squeezed out of formal inquiry. Yet at the margins, exploration continued and expanded. These explorers gradually wedged themselves back inside the bounds of legitimacy. Still, even as new pioneers broadened the scope of sanctioned investigation, they faced a terrain shaped by old boundaries. Science remained beholden to the state, which continued to determine what knowledge could be pursued and who could pursue it.
Seventy-five years after their introduction into mainstream science, and fifty years since their criminalization, psychedelics have once again garnered widespread attention. As we develop new policies regarding substances with complex histories, tales of the past become ever more important. The history of psychedelic science in the United States reveals the epistemic and human costs of institutional conservatism. Democratized experimentation offers alternative paths for healing–a fundamental right and an urgent need in an era of widespread mental distress
Geometric Optics of the Human Eye: From Thin Lenses to Spherocylindrical Corrections
No full textVision correction sits at the intersection of physics and physiology. This thesis explores how the principles of geometric optics not only explain visual defects but also provide the framework for their correction. Beginning with foundational concepts in the electromagnetic spectrum and the physics of light propagation, I establish how visible light\u27s behavior underpins all visual processes. The thin lens approximation serves as an entry point to optical modeling, offering simplified but powerful tools for initial understanding of image formation and correction. I expand the analysis to include multisurface and thick lens systems that more accurately represent the complex optical structures found in the human eye. This realistic optical model incorporates the eye\u27s anatomical structures and their respective refractive indices to explain both normal vision and common aberrations. I provide an analysis of refractive errors including myopia, hyperopia, and presbyopia, using lens equations to quantify correction strategies with eyeglasses. A special focus is given to cylindrical lenses and the geometric principles behind the correction of astigmatism, including the interval of Sturm, circle of least confusion, and spherocylindrical prescriptions. Throughout, I emphasize the clinical relevance of geometric modeling, highlighting how optical principles directly inform diagnostic techniques, the design and fitting of corrective devices, and surgical interventions. By bridging physical theory and physiological application, this thesis emphasizes the value of geometric optics in both understanding visual disorders and guiding their correction in clinical practice