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Cliques of Orthogonal Bases in the E8 Root System
Full text linkQuantum information theorists have recently shown interest in quantum isomorphisms [1],a weaker form of isomorphism between graphs. Naturally, we might look for examplesof graphs that are quantum isomorphic, but not isomorphic. One such example of thisappears in Schmidt [7]: a certain graph ¯Γ1 is quantum isomorphic, but not isomorphic, tothe orthogonality graph ΓE8 of the E8 root system. The orthogonality graph ΓE8 has the120 positive roots in type E8 as vertices, and adjacency is determined by orthogonality.However, the construction of ¯Γ1 given by Schmidt does not use the E8 root system. If thegraphs ¯Γ1 and ΓE8 are related somehow, there should be an expression of ¯Γ1 that is relatedto E8. Green and Xu [3] addressed this by giving an explicit description of ¯Γ1 as the graphΓ ∼= ¯Γ1 in terms of the E8 root system. The central object in this construction is the setX of orthogonal bases of positive roots in E8. This set has a rich combinatorial structure,including a partial order and a quasiparabolic structure. We will use quasiparabolic setsin the sense of Rains and Vazirani [6], where a quasiparabolic set is a set with a specialinteger-valued function and an action of a Weyl group. Using this structure, we can createa subset Xe I ⊆ X of 120 specific bases of roots. The graph Γ has the bases in XeI as vertices, and two vertices are adjacent when these bases are disjoint.</p
A Republican Empire: The Dual Legacy of Simón Bolívar
Full text linkGran Colombia was once one of the Americas’ largest and most promising states. A giant on thecontinent, it spanned from Venezuela to Ecuador, held client states in Peru and Bolivia, andexpelled the Spanish and their Royalist allies from the Northern Andes. It began in 1819, withthe Congress of Angostura, and fell in 1831 with the death of its most prominent figure, SimónBolívar. Bolívar's tenure as president presents us with a view of Gran Colombian politics, wherean elite Creole class of whites born in America became the inheritors of colonial power andstruggled to reconcile their liberal and Enlightenment ideals with their self-interest and resistancefrom subaltern classes. This new Creole ruling class led Gran Colombia through a successfulrevolution, but their prejudices and self-interest, coupled with the hardships of war, posed aserious barrier to a lasting social revolution.
The period between 1810-1849 is the foundation of Latin American politics. Many of the normsset for political action find their origins in the period between 1810-1831, when humanist liberalgoals were challenged by the realities of local interests and where idealists sought to maintaintheir vision through a tightening grip. The political legacy of the Spanish colonial system shapedboth the brightest and darkest sides of these flawed, but well meaning figures. Indigenous andAfrican communities played large roles as political actors, and often shaped the opposition toliberals and Revolutionaries when their policies were ill-conceived. Simón Bolívar's politicalproject resulted in both his liberal humanism and his paternalistic push for autocracy in differentstates at different times. For Indigenous and African communities, the authoritarian states thatemerged oftentimes meant stagnation in the name of stability, leading to further struggle in thewake of the failed Bolivarian social revolution.</p
Comparison of Climate Variability and Mean Temperature as Expressed in Water Isotopes from Two High-Resolution Greenland Ice Cores
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Ice cores contain a continuous record of past climatic conditions that can date back tens of thousands of years, and in some cases millions of years. In this study, water isotope records - a proxy for local temperature - are analyzed for the Greenland Ice Sheet Project 2 (GISP2) ice core and the East Greenland Ice Core Project (EGRIP) ice core. These records extend into the last glacial period. Spectral analysis techniques are used in climate research to observe the variability of the climate system on specific time scales (e.g. decadal, as used in this study) compared to the mean temperature over windows of time (e.g. 200 year windows, as used in this study). Understanding how temperature variability and other climate influences evolve over time compared to the mean temperature can provide insight into climatic drivers. Prior studies have shown larger amount of decadal-scale temperature variability observed during colder climates of the glacial period, which points to the potential impacts of sea ice fluctuation on climate, a hypothesis put forward by Brashear et al. (2025) based on results from the EGRIP ice core. In this study, I use new data from the GISP2 ice core to test the replicability of the Brashear et al. (2025) results. I compare the decadal-scale variability between the two high-resolution ice cores to determine if climate is expressed differently at two locations in Greenland, the ice sheet summit (GISP2) and the northeast flank of the ice sheet (EGRIP). Brashear et al. (2025) found a multi-hundred year offset between declines in decadal water-isotope variability and abrupt temperature increases in the glacial period for EGRIP. I test whether this phase offset is also present for GISP2 for two abrupt warming events, the Bolling-Allerod and the end of the Younger Dryas. I finally interpret decadal-scale variability for the deuterium excess parameter, a proxy for moisture source conditions (e.g. sea surface temperature) of the snow that falls at an ice core site and post-depositional sublimation of that snow. The two ice core sites reveal notable differences in the deuterium excess variability at certain times.</p
Dynamic Light Scattering from Ferroelectric Liquid Crystals
Full text linkWithin the vast landscape of ordered fluids, the long theorized but only recently discovered ferroelectric liquid crystals, exhibiting spontaneous polar order with magnitude comparable to solid state ferroelectrics, have carved their way into the forefront of soft matter research. With high sensitivity to electric fields and striking optical behavior, these materials could prove extremely useful in a broad range of applications. Among the soft materials demonstrating ferroelectricity, of particular interest to this work is the molecule DIO [2,3',4',5'-tetrafluoro-[1,1'-biphenyl]-4-yl 2,6-difluoro-4-(5-propyl-1,3-dioxane-2-yl) benzoate], which has been found to exhibit an antiferroelectric smectic-Z and ferroelectric nematic phase. These novel phases have previously been characterized by optical and SHG microscopy, x-ray diffraction, calorimetric studies, and capacitance studies. Dynamic light scattering can be used to probe the Frank elastic constants and viscosity coefficients directly. I have carried out dynamic light scattering experiments to investigate the phases and phase transitions of DIO, studying its viscoelastic properties in order to gain insight into the physical mechanism that drives the transitions and help validate theoretical models describing the ferroelectric phases.</p
Elucidating Streptococcus agalactiae and Staphylococcus aureus Polymicrobial Interactions in Diabetic Wound Infections
Full text linkDiabetic foot ulcers (DFUs) are a leading complication of diabetes mellitus due to theirpropensity for infection and poor healing, which results in significant morbidity and financialburden for patients. Various pathogenic species, representing several bacterial and fungal genera,perpetuate polymicrobial infections within the wound environment. Particularly prevalentspecies include Streptococcus agalactiae, or Group B Streptococcus (GBS), and Staphylococcusaureus, which serve as the focus of this study. Preliminary data suggest that S. aureus maycontribute to an increased burden of GBS in diabetic wounds through synergistic interactions,enhancing the overall severity of infection. This study examines mono- and dual-species biofilmassays, bacterial growth curves, and investigation of nutrient sharing between GBS and S. aureusin clinical DFU isolate samples collected at the University of Colorado Anschutz. These methodsserve to elucidate the mechanisms driving polymicrobial synergy between GBS and S. aureuswithin the DFU environment. Moving forward, the dynamics of these interactions could informthe development of novel DFU infection management approaches that inhibit polymicrobialpathologies, ultimately improving patient outcomes.</p
Theatre as Revolution: Popular Theatre and Anti-Imperialism in the Dominican Republic (1960s-Present)
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This paper explores the role of popular theatre as a tool for anti-imperialism in the Dominican Republic, tracing its evolution from the oppressive political climate under Rafael Trujillo’s dictatorship to the post-revolutionary era marked by United States intervention and political upheaval. The study investigates how theatre became a medium for resistance and social critique, particularly following the rise and fall of President Juan Bosch in the 1960s. Despite the brief nature of Bosch’s presidency, it sparked an artistic renaissance, which was abruptly interrupted by a military coup and United States intervention. However, the ideals of the 1965 April Revolution—though politically thwarted—continued to fuel the development of popular theatre. This type of theatre, defied state censorship and promoted anti-imperialist themes. This research employs qualitative methods, including textual analysis of plays such as Espigas Maduras by Franklin Dominguez, and conversations with key figures such as Manuel Chapuseaux and Clara Morel to examine the strategies and evolution of popular theatre as a tool for anti-imperialist activism. Ultimately, the paper argues that Dominican popular theatre has played a critical role in challenging power structures, fostering cultural identity, and contributing to the broader struggle for social and political change in the Dominican Republic, in opposition to the lasting impacts of US imperialism on the Dominican nation. </p
The Co-Production of an Apparatus of State Coercive Necropower: Understanding the Relationship between the Department of Homeland Security and Border Civilian Patrol Group “Arizona Border Recon”
Full text linkThis thesis combined two theoretical frameworks of Achille Mbembe’s Necropolitics and Antonio Gramsci’s understanding of Cultural Hegemony and applied them to examine the relationship and negotiation between state and nonstate actors at the border. My thesis sought to analyze how interests around “securing” the border between state actors within the Department of Homeland Security (DHS), specifically Customs and Border Protection (CBP), and nonstate actors of border civilian patrol groups, specifically the group Arizona Border Recon (AZBR), may intersect and/or diverge. I leaned on Alfonso Gonzales’ (2014) application of Gramscian theory to DHS actions and his larger argument situating “anti-migrant hegemony” as the current-day ideological leadership in the US. Policy and media analyses were performed to analyze this relationship. I found that the interests of state and nonstate actors both intersect and diverge but display more sites of intersection than divergence. Interests between the groups intersect around perceived missions/goals as protection of a “way of life/worldview” and around perceptions of the US as in a state of crisis, while a divergence of interests can be seen in behavioral discrepancies between actors, such as promptness of reporting migrant bodies. These intersections in light of the formal partnership between these groups should be used to consider how DHS and AZBR use this shared framing to deploy an apparatus of state coercive necropower against all who do not consent to notions of common sense. This is important as this co-produced apparatus of state necropower impacts everyone in society in differential ways. My findings may be used by various scholars, such as those in disciplines of immigration, border politics, international affairs, and sociology, or additionally by NGOs or governmental agencies such as CBP.</p
Exploring the Moderating Role of Socioeconomic Status in the Relationship Between Inflammation and Cognitive Function
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This study examines the interaction between inflammation, socioeconomic status (SES), and cognitive performance, focusing on working memory as a key cognitive domain. Using data from the Effects of Stress on Cognitive Aging, Physiology, and Emotion (ESCAPE) project, we investigated the moderating role of both objective and subjective SES in the relationship between C-reactive protein (CRP) levels and working memory performance. The sample consisted of 202 adults aged 25-65 (M = 46.46, SD = 11.08) from Bronx County, New York, with varying levels of SES. Multiple regression analyses revealed that lower subjective SES, as measured by the US ladder, combined with higher CRP levels, was associated with improved working memory performance. This effect was not observed for objective SES indicators, such as income and education. Further analyses explored the moderating roles of age, sex, and ethnicity, revealing that low education and higher CRP were linked to better working memory in younger individuals. However, post-hoc adjustments for multiple comparisons rendered most of these effects non-significant. Additional follow-up analyses showed that high income and low basal cytokines predicted better working memory performance, while low subjective SES combined with low stimulated cytokines predicted better working memory in younger individuals. No significant findings were observed for episodic memory. These results suggest that the relationship between inflammation, SES, and cognitive function is complex and may be influenced by both biological and psychosocial factors.</p
A System Stacked Against Them: A Quantitative Analysis of Misconduct among Incarcerated Men with and without Intellectual or Developmental Disabilities
Full text linkThis study examines whether incarcerated men with intellectual and/or developmental disabilities in a western U.S. state prison system receive a higher proportion of disciplinary infractions compared to those without such disabilities, while also investigating racial disparities. Using administrative data from 93,587 incarcerated persons collected between 2008-2020, the study employed chi-squared tests to analyze differences in misconduct proportions. The research draws on both general strain theory and the focal concerns framework to understand how disability characteristics and officer discretion may influence disciplinary outcomes. Results indicate that incarcerated men with intellectual or developmental disabilities were ticketed at higher proportions across specific infraction categories (property, violent, threat, security, and defiance), though differences in broader misconduct categories were not statistically significant. Drug-related infractions presented an exception, with higher proportions among those without disabilities. Significant racial disparities were observed among incarcerated men with intellectual or developmental disabilities, with Black men generally receiving the highest proportion of infractions across most categories and Hispanic men receiving the fewest. These disparities may result from how symptoms of intellectual and developmental disabilities manifest in prison settings, particularly regarding social communication difficulties and needs for routine and predictability. Institutional factors, including limited officer training on recognizing disability-related behaviors and the absence of formal processes to evaluate whether behaviors stem from disabilities, likely contribute to these disparities. This research highlights the need for improved staff training, specialized accommodation procedures, and potentially the implementation of manifestation determination processes similar to those used in educational settings for incarcerated persons with intellectual and developmental disabilities.</p
Norwegian Newspaper Coverage of Climate Change or Global Warming, 2000-2025 - May 2025
No full textThe Media and Climate Change Observatory Data monitors 131 sources (across newspapers, radio and TV) in 59 countries in seven different regions around the world. Data is assembled by accessing archives through the Lexis Nexis, Proquest and Factiva databases via the University of Colorado libraries. More information may be found at: http://mecco.colorado.edu.</p
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