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Item Mi casa es tu casa: Investigating Cohabitation and Inflation Rates in Gran Buenos Aires(Rice University, 2024) Frizzell, Brendan; Bratter, JeniferOver the past few decades, cohabitation in Latin America has increased. The rise of cohabitation, defined as a non-married couple living together in one household, has been attributed to cultural shifts in openness to alternative methods of family formation, economic hardships, and the belief that cohabitation can serve as a logical precursor to marriage. Studies on cohabitation have not conclusively attributed a single cause to this trend; however, I theorize that the rise of cohabitation in Latin America occurs primarily because of economic conditions. Given the rapid inflation and increasing cost of living in Gran Buenos Aires (GBA), I investigate cohabitation in relation to the current socioeconomic context. Using individual and household datasets collected by el Instituto Nacional de Estadísticas y Censos (INDEC) on a quarterly and monthly basis from 2017-2023, I employ a quantitative approach to evaluate how rising inflation in Argentina affects residents of GBA. From 2017-2023, the quarterly inflation rate maintained similar trends as the quarterly cohabitation rate. Binomial logistic regression finds that inflation was not a significant predictor of cohabitation; however, when evaluating households with only two residents, there was a 1.1% increased likelihood they were cohabiting. In two-person households, across all five age groups, there was a significantly positive relationship, indicating as inflation rose so did the prevalence of cohabitation amongst two-person households across age. Future research should continue to investigate cohabitation in relation to economics, as it informs how and when families form and the way economic hardship affects families. More should be done to include qualitative methodologies and additional measures alongside inflation indicating economic stability to create a more comprehensive measure of economic circumstances influencing family formation and cost-sharing.Item Final Report on Degradation of "Scholar's Way" for the Museum of Fine Arts, Houston(2023-05-02) Rajan, Bavan; Siebach, KirstenThe purpose of this project is to understand the chemical processes that contribute to the degradation of “Scholar’s Way,” a trio of heavily altered basalt sculptures at the Museum of Fine Arts, Houston (MFAH). They were installed at the MFAH in 2020 after their creation in 2018 by South Korean artist Byung Hoon Choi. The work sits in a shallow pond in the museum’s sculpture garden, exposed to Houston’s warm humid climate and regular HCl from treatments to prevent algae growth. After less than 3 years, fragments of the sculptures have been lost, the surfaces have altered in coloration, and salt-like minerals regularly precipitate on the sides of the sculptures. The mineralogy of the sculptures and associated precipitates can inform the MFAH of how and why “Scholar’s Way”, as well as other outdoor sculptures, might be degrading, as well as what steps they can take to preserve their artwork. Visual and Near Infrared Spectroscopy, speciation modeling from the pond’s water chemistry, Electron Dispersive X-ray spectroscopy, and Electron Probe Microanalysis were used to determine 1) the chemical composition of the water features and sculptures, which reveal plausible degradation mechanisms, 2) potential ongoing mineral dissolution, and 3) the drivers of salt precipitation from the pond. These results, along with recommendations to preserve the work, have since been presented to the MFAH in the attached executive summary and technical report.Item Phases in Ultracold Interacting Rydberg Atom Systems With The Su-Schrieffer-Heeger Model Engineered On A Synthetic Dimension(Rice University, 2023) Dyall, Charles; Hazzard, KadenSynthetic dimensions encoded into atomic states have emerged as a powerful tool for engineering new phases of matter. These synthetic dimensions are helpful in accessing confgurations that are difcult or impossible to simulate using real space alone. Using Rydberg states to encode these synthetic dimensions allows a high level of control over system parameters. Here we use a mean-feld theory approach to investigate phases of matter that occur in Rydberg atoms with attractive interaction in real space with the synthetic dimension encoded such that it emulates a Su-Schriefer-Heeger (SSH) model lattice. We fnd that this model displays both two and three-site quantum strings in the ground state that demonstrate substantial crossover with larger strings and two-site string phases, respectively.Item Differences between modern and ancient Martian grain size distributions may reveal different paleoatmospheric conditions and provenance(Rice University, 2023) Preston, Sarah Lucille; Siebach, KirstenGrain size distributions in eolian (wind-blown) deposits encode information about the atmospheric conditions that enabled their transport and deposition, and grain shape encodes information about provenance and postdepositional processes. Gale crater is a ~3.7 Ga impact crater with a vast diversity of exposed sedimentary strata indicative of a varied depositional history during the ear ly Hesperian epochs (Banham et al., 2018). The Stimson sandstone is a ~3 Ga unit of eolian sandstone in Gale crater that appears to have a coarser grain size distribution than the nearby Bagnold Dunes, an active dune field (Banham et al., 2018; Weitz et al., 2018). In this work, I hypothesize that the Martian paleoatmosphere had a different density than Mars’ current atmosphere, and that the source of the Stimson sandstone may have been more coarse than the source of the Bagnold dunes, leading to ancient sandstones with different grain size distributions than modern active sand dunes. To approach this question, I analyze images from the Mars Science Laboratory (MSL) Curiosity’s Mars Hand Lens Imager (MAHLI) and Remote Micro Imager cameras to determine the grain size distribution of targets. Additionally, I qualitatively describe grain shape and appearance, including roundedness, sphericity, pitting, and color, along with chemical composition where possible, to determine whether differences in grain size distributions can be attributed to provenance. From these results, I explore the role of paleoclimate and provenance in generating the grain size distribution seen in the Stimson. These results will help determine the provenance of the Stimson, as well as ancient Martian atmospheric conditions, in turn providing insights into the wet-to-dry transition and, potentially, the habitability of ancient Mars.Item The Effect of Nitrate Availability on Oxygen Isotope Fractionation During Cyanobacterial Photosynthesis(Rice University, 2023) Guo, Lingkun; Yeung, LaurenceMarine primary productivity supports food webs and ecosystem health, driving large-scale animal distribution patterns in the ocean. Primary productivity is also a fundamental process in the biological pump, which sequesters inorganic carbon from the atmosphere through photosynthesis and transports it to the ocean interior where it can be stored for millennial or greater timescales. Presently, different methods for quantifying productivity disagree with each other, presenting a major research challenge. To understand how climate change may impact the biosphere, it is necessary to continuously improve methods for quantifying primary productivity. The isotopic composition of dissolved oxygen in the ocean can be used as a constraint on oxygen production and therefore, be used to quantify marine primary productivity through the carbon-oxygen stoichiometry of photosynthesis. To distinguish newly produced O2 from O2 already present in the atmosphere, the 18O/16O and 17O/16O ratios of dissolved oxygen can be used. This approach is termed the “triple-oxygen isotope (TOI) method” and it relies on laboratory studies of the behavior of oxygen isotope ratios during photosynthesis to constrain field measurements. Despite the potential of the TOI method, major knowledge gaps remain. For example, nutrient availability affects the photosynthesis activity of microorganisms and is heterogeneous across global oceans. Therefore, understanding how oxygen isotope fractionation may vary under nutrient str ess is crucial for correctly interpreting field measurements. To address this knowledge gap, this study examines the effect of nitrate availability on the isotopic composition of cyanobacterial photosynthetic oxygen. Freshwater cyanobacteria Synechocystis PCC 6803 are inoculated in media with different nitrate concentrations. The cyanobacterial photosynthetic oxygen is collected and its TOI composition is analyzed. Additionally, this study generates new data on the clumped isotope composition of photosynthetic oxygen, which is a parameter describing the degree of randomness in the distribution of rare oxygen isotopes (17O and 18O) in O2 molecules. Results suggest that there is larger oxygen isotope fractionation when cyanobacteria experience more nitrate limitation, and that the TOI and clumped isotope composition of photosynthetic oxygen can be utilized together to constrain gross oxygen production and provide information on the mechanism of cyanobacterial photosynthesis.Item Understanding Phosphorus Mobility in Arclogites(Rice University, 2023) Potemkin, Stella; Cin-ty LeePhosphorus (P) is an essential nutrient for life. Throughout geologic time, availability of this element has limited primary productivity. Therefore, understanding how the phosphorus moves through Earth system has important implications for understanding life history. While surface fluxes of phosphorus are well studied, less attention has been given to understanding how P is recycled and moves through igneous systems. This thesis uses arclogites, a type of garnet pyroxene xenolith, as a tool to better understand P mobility in continental arc settings. We collected quantitative mineral chemistry for four thin sections using wavelength-dispersive spectroscopy (WDS). Additionally, we analyzed existing whole-rock major element compositions for our four thin sections and additional arclogite samples with bulk rock P2O5 greater than 0.2 wt%. Mineral volumes were estimated using Image-J and existing point count data. The culmination of these data allowed us to investigate what contributions different mineral phases make towards bulk rock P2O5. Our research suggests that titanite and apatite are the main carriers of P in these rocks, however, questions remain about whether these minerals are primary features. This work expands our understanding of P mobility in arclogites and could have implications for our understanding of how the global P cycle has evolved throughout Earth history.Item Changes in Atlantic Tropical Cyclones and the Bermuda High: Clues from the Last Millennium to Inform the Future(Rice University, 2023) Pitchon, Emilia; Dee, SylviaCurrent anthropogenic climate change is expected to increase hurricane intensity, with stronger winds, higher rainfall, and increased flooding, all of which pose a major threat to coastal communities. However, climate models vary in their predictions of how climate change will impact hurricane frequency and tracks, and 20th century data sources are limited given the brevity of the satellite era. To address this knowledge gap, we study the strength and position of the Bermuda High and how it has changed over the past millennium. The Bermuda High is a semipermanent high-pressure system over the Atlantic Ocean which impacts hurricane tracks and steering currents. To study its behavior, we evaluate two climate products with sea level pressure data spanning the past 1000 years: the Last Millennium Reanalysis and the Community Earth System Model. We compare various Bermuda High indices (BHI) as defined by previous studies, representing different measures of position and strength of the high-pressure system. Maps of sea level pressure anomalies and hurricane tracks are generated during years with high vs. low BHI values. This allows us to better understand the relationship between the Bermuda High and hurricane characteristics over the last 1000 years, providing important context for the future. This work is critical to better constrain hurricane risks under anthropogenic climate change and may help protect the people and environments at risk.Item Environmental Control in Appalachia: Politics of the Red River Gorge Dam Controversy, 1962-1975(Rice University, 2022-03-30) Cook, Kamil; Hall, RandalIn 1962, Congress approved the building of a dam on the Red River in Eastern Kentucky because of recurring floods affecting Powell County, Kentucky. This dam threatened a beautiful and ecologically unique part of the Red River, and, in response, in 1967 a group of environmental activists gathered together to challenge the building of this dam. After a contracted battle involving the Army Corps of Engineers, environmental activists, politicians, and local people, the dam was never built. Along with chronicling this controversy, my thesis explores the changing conceptions of the environment through the 1960s and 1970s and illustrates that Appalachian environmental activism not only existed, but was contemporary with national movements. I do this with the support of newspapers, letters, legal records, bureaucratic reports and more gathered from the Red River Gorge archive at the University of Kentucky and an online newspaper database.Item Freedom’s Archive: Slavery, Emancipation, & Reconstruction in Fort Bend County(Rice University, 2022-05) Schachter, Ben; McDaniel, CalebThis thesis tells the story of the Wheat family from their enslavement in Fort Bend County by Frederick Allen Rice through their experiences during emancipation, Reconstruction, and Jim Crow. It studies questions of change and continuity and grapples with the inadequacies of traditional sources to try and tell a rich, colorful story of one Black family's life. The thesis finds that while there was certainly some progress from slavery, one family member's gains might be weighed down by setbacks for another. It also argues that freedom's archive is not well-suited to answering the sort of broad, overarching questions historians of this time period often ask when searching for a definitive answer to how revolutionary Reconstruction was. This thesis also asserts the importance of attempting to reconstruct just a few people's lives and their genealogies, emphasizing enslaved people's claims on the present.Item Silences on the Strand: Contesting Public Memories of Slavery and Freedom in Galveston’s Civic Historical Landscape (1871-2021)(Rice University, 2022-05) Landry, Katelyn; McDaniel, CalebOn June 19, 2021, a mural was unveiled in Galveston, TX titled Absolute Equality. It depicts several scenes representative of enslavement and freedom and it is located at the former site of the Union Army Headquarters and where U.S. Gen. Granger read the orders that abolished America’s last vestige of slavery. The mural was unveiled with effervescent local pride in the wake of federal recognition of Juneteenth as a national holiday just two days before. U.S. politicians gave impassioned speeches to a huge crowd and media outlets about the historical and political relevance of celebrating Juneteenth and Galveston’s role in the story of freedom. Six blocks away, in front of the Galveston County Courthouse, the 22 ft. tall Dignified Resignation monument depicts a Confederate soldier. Unveiled in 1911 by the city’s local chapter of the United Daughters of the Confederacy (UDC), the statue’s plaque reads: “There has never been an armed force which in purity of motives intensity of courage and heroism has equaled the Army and Navy of the Confederate States of America.” About ten months before Absolute Equality was unveiled, a motion to remove the Dignified Resignation monument was presented by one county commissioner but it quickly died after no other commissioner seconded the motion, and the issue has yet to be publicly debated again. The coexistence of these two sites is emblematic of the polarized narratives regarding Galveston’s history of slavery and freedom that have jockeyed for influence in the city’s civic historical landscape since the end of the Civil War. For people who are just learning about Juneteenth and registering Galveston as a place that is significant in the national story of slavery, it is easy to get the impression that Juneteenth has always been a well celebrated occasion by the city writ large. This is only partially true -- African Americans in Galveston and beyond have celebrated emancipation on June 19 since 1866, however their collective and cultural memories of emancipation and the preceding centuries of enslavement have only very recently become incorporated into Galveston’s civic historical landscape and made more widely known to the public. Rather than seeing this as a simple story of progress or diversification, this observation led me to ask: Why has it taken so long for this significant piece of Galveston’s history to come to light, and why now? Through my primary source research I have found that Local practices of memorialization and historic preservation have been constructed and enforced in ways that granted white collective memories more visibility and perceived authority in Galveston, and thus marginalized or silenced narratives that would trouble those memories such as a more honest history of slavery on the island.Item Negotiating Mexican Foreign Policy on Cuba: Between Domestic Interests and the United States: 1959-1964(Rice University, 2022-05) Saeki-Serna, Victoria; López Alonso, MoramayThis thesis analyzes Mexico's foreign policy regarding Cold War era developments in Cuba and the United States' response to said policy. It finds that while Mexico oftentimes defied the anticommunist agenda the United States pushed on to Latin America during this period, it did so not as an immediate affront to the United States, but rather to keep a fragile balance among a broad domestic coalition vital to the Institutional Revolutionary Party (PRI). The United States - though initially upset by the foreign policy of Mexico - eventually understood and accepted the domestic considerations behind its neighbor's foreign policy, as it secured the hold of the PRI in Mexico and thus excluded communists from holding significant political power in that country.Item Machine Learning Detection of P-Waves in Laboratory Acoustic Emission Events to Understand Deep-Focus Earthquakes(Rice University, 2022) Sheehan, Jack; Niu, FenglinThe mechanisms of deep-focus earthquakes (DFEQs)—those between 350 and 700 km depth—remain poorly understood due to our inability to directly measure their fault properties in situ. One potential explanation for DFEQ nucleation is the transformational faulting hypothesis, which theorizes mineral transformations initiate the faults. To analyze these structures in more detail, deformation events were conducted in a controlled laboratory environment on 2.1x3.0mm Mg¬2GeO4 samples, the leading mineralogical candidate of the transformational faulting hypothesis. Six orthogonally oriented sensors recorded Acoustic Emission (AE) events to detect P-wave arrival times, returning event-trigger waveform data at 50 MHz and continuous data for 42.4 minutes at 10 MHz. The experiment returned 3,901 event-trigger SAC files and 19,280 continuous SAC files, totaling just over one billion data points. To analyze this large quantity of raw waveforms, this study introduces machine learning as a tool to automate the detection process. A deep-learning-based detector called EqTransformer (EqT; Mousavi et al., 2020) was trained on global seismic data from the Stanford Earthquake Dataset (Mousavi et al., 2019) and applied to the experimental data to perform P-wave detection and arrival time picking. The short-term goal of this project is to determine the robustness of EqT on microseismic data in both event-trigger and continuous forms. Preliminary results indicate the application of EqT on the event-trigger data was successful. EqT detected 93.4% of the events identified manually, as well as 57.3% additional events missed by the human analysts. The long-term goal is to create a definitive catalog of the AE events that occurred in this experiment, using EqT on the continuous dataset. This could potentially offer key insights into the scaling properties of seismic experiments.Item When is Drone Photogrammetry Useful for Flood Risk Assessment?(Rice University, 2021-05) Sheldon, Jessica; Siebach, KirstenDrone technology and the high resolution datasets it enables stand to revolutionize our understanding of the Earth’s surface. This research is Houston specific, and studies how drones can be used to systematically collect photogrammic data to detect environmental changes, and how that data is valuable for flood planning purposes. This data is the culmination of three years of research. Prior to this year, the focus has been learning to fly the drone, learning the image processing Pix4D and ArcMap 10.5, and creating a workflow for accurate image collection processing. This study has collected three separate datasets of the study area at Buffalo Bayou using a DJI Phantom 4 Pro drone. This data was then processed and modeled in Pix4D to create digital elevation models (DEMs). The DEMs were calibrated and analyzed in GIS, and compared to the publicly available 2018 LIDAR data. Our research catalogs high resolution change over time of our study area, and documents the process of how drones can be used to systematically observe change over time. Additionally, our data highlights the difference in resolution between a low elevation drone flight versus a higher elevation LIDAR scan.Item Orgullo Crítico: An Anti-Capitalist Approach To Pride In Spain And The United States(Rice University, 2021-05) Lin, Amy; Sanders, PaulaEvery June, many people around the world come together to celebrate queer identities at various state-sponsored Pride events. However, given the infiltration of rainbow capitalism in mainstream Pride movements, many radical leftists within the queer community have begun to organize anti-capitalist "Critical Pride" protests. In this thesis, I trace the emergence of mainstream Pride celebrations in Spain and the United States and their role in the creation of Critical Pride movements, and I explore how academic queer theory, specifically queer Marxist theory, relates to this form of real-life praxis.Item Expression and purification of LiaX, an uncharacterized protein involved in daptomycin resistance in E. faecalis(Rice University, 2015) DeBruler, Kimberly; Shamoo, YousifItem The Impacts of Concrete on pH and Calcium Concentration in Houston’s Bayous(Rice University, 2021-05) Hale, Meagan; Torres, MarkAs the human population grows, so does the percentage of people living in urban areas. This means that an increasing amount of landmass must be used for urban infrastructure and housing to accommodate a greater number of people. The environmental impacts of urbanization are not completely understood. However, one important aspect that may be impacted is water quality. For instance, the concrete used to construct water transport and drainage systems can leach Ca2+ions into urban rivers and increase water pH. These changes are of concern because pH range is a major factor in determining the toxicity and bioavailability of chemical compounds. Additionally, many aquatic microorganisms can only thrive within certain ranges of pH and Ca concentrations. To investigate how the concrete used in urban infrastructure impacts water quality, I studied two major rivers in Houston, TX, USA. The first, White Oak Bayou, is lined with concrete; the second, Buffalo Bayou, has a natural river bottom. These two rivers were compared with the non-urban but still geographically similar Trinity River, since river chemistry may be affected by the presence of concrete anywhere within a river’s watershed. I collected water samples from Buffalo and White Oak bayous and analyzed their major anions and cations using ion chromatography (IC) and inductively-coupled plasma mass spectrometry (ICP-MS) methods, respectively. In addition, I analyzed roughly 50 years’ worth of public water quality data for each bayou and the Trinity River. The data suggest that the concrete-lined White Oak Bayou has a higher Ca concentration and pH value than Buffalo Bayou. The results of this research expand our knowledge of the environmental impacts of water transport and drainage systems.Item Affection: Essays on Affect, Empathy, and the Politics of Feeling(Rice University, 2021-05) Li-Wang, Jennifer; Comer, KristaOften, we view feelings as squishy—personal and subjective, therefore private and apolitical. Even within ourselves, our feelings can often seem reflexive and out of our own control. This thesis represents my attempt to hold these squishy feelings and look at them up close, from different angles. In doing so, I hope to see how our affects may not only be personal to ourselves, but also highly communal, performative, and regulated by and within communities. Affects—our feelings, emotions, and moods—are a matter of political and intellectual concern. Different political aims often mobilize our affects and manipulate them to conform to certain desirable shapes. Thus, paying attention to affects—the ways they are evoked, politicized, and ascribed (un)desirability—may help us stay close to our own needs and the needs of our community.Item Critical Theory, Normativity, and Catastrophe: A Critique of Amy Allen’s Metanormative Contextualism(Rice University, 2020-05) Rehman, Bilal; Crowell, StevenCritical theory is an approach to philosophical and cultural analysis that focuses on oppression and liberation. In this essay, I consider the prospect of moral-political progress in critical theory, focusing primarily on Amy Allen’s position of metanormative contextualism as described in her 2016 work, "The End of Progress." I first consider Allen’s arguments against Jurgen Habermas' theory of communicative action, and then explore how metanormative contextualism is rooted in the thought of Theodor Adorno and Michel Foucault. Lastly, by showing how postcolonial studies reminds us of the deeply political stakes of critical theory, I argue that ideas about moral-political progress can be grounded in the urgent need to “avoid catastrophe.”Item Glacially-controlled variations in the biological pump of the Ross Sea in the Mid-to-Late Pliocene(Rice University, 2020-05) Nirenberg, Jared; Ash, Jeanine; Masiello, CarrieThe mid-to-late Pliocene (~3.3 – 2.5 Ma) is an intriguing period for investigating Earth’s past climate dynamics as a potential analogue for future warmth due to anthropogenic climate change. In the Southern Ocean, the Ross Sea and the adjacent West Antarctic Ice Sheet exert significant influence on global climate through their roles in carbon cycle processes, deep ocean circulation, and eustatic sea level. Previous ocean drilling records have shown that the marine-based West Antarctic Ice Sheet exhibited highly dynamic behavior in the Pliocene and responded to cyclical variations in Earth’s orbital geometry. However, fundamental questions remain regarding the biogeochemical response of Southern Ocean marine productivity to changes in ice sheet dynamics and sea ice cover. The International Ocean Discovery Program’s Expedition 374 to the Ross Sea (2018) recovered multiple sediment cores, including those from Site U1524 on the continental rise. I present a 900,000 year record of the carbon and nitrogen content in bulk sediment in the Pliocene-aged cores from Hole U1524A. This record shows the response of carbon export from the Ross Sea continental shelf to orbital and longer-term forcings of the West Antarctic Ice Sheet and global climate. From 3.3 to 3.0 million years ago, I observe a gradual, non-monotonic increase in organic carbon to nitrogen ratios, followed by a decrease from 3.0 to 2.8 million years ago. Sediment color reflectance measurements, implying changes in surface water productivity, are tightly anti-correlated with organic carbon to nitrogen ratios between 3.3 and 3.0 million years ago, but are positively correlated between 3.0 and 2.8 million years ago. I discuss these trends in the context of concurrent sedimentology, physical oceanography, and ice-sheet dynamics. Finally, I note that potential diagenetic effects limit interpretation of this record, and I suggest that bulk carbon and nitrogen stable isotope measurements combined with compound-specific analyses may provide more insight into carbon and nitrogen cycle dynamics during the mid-to-late Pliocene.Item Competing Claims: An Analysis of References to the Past Made to Justify Ownership of the Mosque-Cathedral of Córdoba(Rice University, 2019-05) Panitz, Abigail; Wildenthal, Lora; Irish, Maya SoiferCompeting claims of ownership to the Mosque-Cathedral of Córdoba, a popular tourist site, have emerged in the twenty-first century. The Cordoban Chapter of the Catholic Church was permitted to register the space as its formal property in 2006. Some politicians, particularly members of Spain’s Socialist party, the PSOE, dispute the law that allowed this registration. In their view, the law was passed as part of the conservative People’s Party’s strategy to protect privileges afforded to the Church. The thesis analyzes two reports to demonstrate how two groups, the state and the Church, relied on distinct episodes of Spanish history to support their claims. A 2014 local Church report used nineteenth- and twentieth-century property laws to defend its claims to ownership. A 2018 local government report used the medieval legal code Las Siete Partidas to argue for restoring the space to state control. The dispute in Córdoba is a microcosm of the challenges affecting church-state relations in the post-dictatorship era of secular democracy in modern Spain.