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FEMINISM, SOCIALISM, AND EVOLUTIONARY BIOLOGY: UNDERSTANDING DEGENERATION IN EMMA FRANCES BROOKE’S A SUPERFLUOUS WOMAN.
No full textWith the growing concern about evolutionary degeneration in the last quarter of the nineteenth century, discussion turned to potential avenues by which society might be regenerated. For many, the new science of eugenics, built upon principles of natural and sexual selection as described by Charles Darwin, promised the answer. The predominant history of eugenics focuses on its application by white, middle class, males to maintain racial, class, and gender boundaries. However, in recent years, historians such as George Robb and Angelique Richardson have both highlighted ways that the language of evolutionary degeneration and eugenics was appropriated to counter the status quo, and call for social and political reform. While eugenics may seem at first opposed to the goals of feminism and vice versa, many feminist writers and thinkers employed eugenic principles and language in order to bolster the scientific validity and appeal of their arguments. Emma Frances Brooke, feminist, socialist, and New Woman author, used biological and eugenic language in her 1894 novel A Superfluous Woman to discuss the social and sexual boundaries that were set for women, as well as how these impacted gender relations and equality, female labor, reproductive rights, and the nature and meaning of marriage and of motherhood, ultimately leading to degeneration. An historical analysis of Brooke’s work that pays attention to the history of biology, and specifically to the history of evolutionary ideas about progress, degeneration, and their relation to eugenics, affords us a deeper insight into the social and political issues that were at stake in what was called the “woman question.” Brooke’s work is grounded in ideas of heredity, as well as natural relationships between men and women and the ways that society impacted these relationships. For Brooke, the threat of evolutionary degeneration was thwartable through the education of women, and female choice in sexual partners, a more natural attraction based alternative to the contemporary male-led “marriage market.
Characterization and Performance Evaluation of a Double Rolling Isolation System with Response-Based Adaptive Behavior
No full textStructural engineers are tasked to create devices to mitigate the catastrophic effects of natural disasters such as earthquakes. For example, seismic demands can be decreased by lengthening the natural period of a system, which can be achieve through base isolation. Rolling isolation systems (RISs) utilize rolling-pendulum isolators composed of two concave rolling surfaces and a rolling element. These systems’ performance is characterized by their displacement capacity and their ability to reduce transmitted accelerations. However, when a ground motion introduces displacements greater than that of the bearing’s capacity, then the isolation system fails to perform its function, giving rise to even higher accelerations. Methods to reduce displacement demand involve using an elastomeric material to increase rolling resistance (damping) at the expense of introducing higher accelerations into the system. These isolation systems should be designed to reduce both excessive displacements and elevated accelerations, which requires the use of a response-based adaptive behavior. Response-based adaptive behavior aims to achieve desired responses during certain levels of excitation. That is, during low-intensity (service) excitations, the system focuses on acceleration reduction so light damping and low stiffness is used, whereas stronger base excitations prompt the system to focus on displacement reduction and initiate a larger damping response and higher stiffnesses. This framework is investigated through a double RIS which has two RISs working in series, which allows for the customization of unique parameters in the subsystems that provide desired responses for the system. The rolling surfaces are modeled after a Ball-N-Cone design that allows for a parameterized design consisting of an inner radius, constant sloped length, and outer radius. Additionally, utilizing different materials for the rolling elements (steel and rubber) allows for different damping levels to be achieved. A double RIS is experimentally constructed and subjected to quasi-static and shake table tests to characterize the system and evaluate its performance through peak accelerations, respectively. To complement the experimental system, a physics-based mathematical model is derived for the system which generates the equations of motion of the system. The numerical work consisted of running simulations with this model to acquire peak responses both in displacement and acceleration. Results indicate that utilizing a double RIS to induce certain staged responses does achieve this response-based adaptive behavior. Furthermore, the performance of the double RIS maintains a wider operating range where peak accelerations are reduced. While the operating range of the double RIS improves the response when compared to its individual subsystem results, a second mode is realized at higher frequencies in the double RIS. This second mode introduces a detrimental response to the double RIS. Further optimization techniques are suggested to continue to improve the response of a double RIS using response-based adaptive behavior
Cultivating a National Awareness: Colombian Nationalism in the Music of Guillermo Uribe Holguín and Antonio María Valencia During the First Half of the Twentieth Century
No full textThroughout its extensive history marked by multiculturalism and foreign influences, Colombia has continually embarked on a quest to define its identity. The significant rise in cultural and musical development during the latter part of the nineteenth century prompted the need to establish Colombia’s own musical voice. This posed a monumental challenge for composers of that era, who had to forge an artistic national identity amidst competing ideals. On the one hand, the judgment and value of musical works during the first half of the century were based on folk-inspired art. On the other, a modern approach sought to assimilate Western musical conventions into national compositions to broaden the music's international appeal. Central to this discourse were Guillermo Uribe Holguín (1880–1971) and Antonio María Valencia (1902–1952), two leading composers of their generations who emerged as pivotal figures in defining a Colombian national musical identity. They are revered as some of the pioneering professionals advancing composition and music education methods in the country. The analysis of their works Sinfonía No. 2 Del Terruño op. 15 (Uribe Holguín) and Emociones Caucanas (Valencia) will provide a deeper understanding of each composer’s perspective on the subject, as these pieces distinctly illustrate the articulation between European and nationalist elements. This analysis will also offer insight into how both composers navigated a predominantly European music scene, allowing for a greater appreciation of the enduring nationalist influence in Colombian music
APPLICATION OF SUPERVISED CLASSIFICATION AND TIME-SERIES MODELS ON PREDICTION OF UNDESIRABLE EVENTS IN OFFSHORE OIL PRODUCTION
No full textAbstractOffshore oil production is faced with critical challenges due to rare but high-impact undesirable events that disrupt well operations. The early prediction of events such as sudden water breakthroughs, valve failures, flow instabilities, and blockages is considered essential for preventing production losses, environmental incidents, and safety hazards. Traditional physics-based models are often limited in handling the complex, multivariate nature of these problems, whereas supervised machine learning and time-series modeling are increasingly applied to provide data-driven solutions for detecting subtle patterns that occur before failure. In this thesis, the application of supervised classification algorithms and temporal models has been investigated for the purpose of predicting undesirable events in offshore oil wells. A publicly available dataset (3W), which contains over 50 million sensor readings from an offshore field with eight documented types of production anomalies, has been used as a benchmark. A detailed study of the production challenges represented in the data has been carried out, including anomalies such as Abrupt Increase of BSW (Basic Sediment and Water), Spurious DHSV closures, Severe Slugging, Flow Instability, Rapid Productivity Loss, Quick Choke Restrictions, Scaling, and Hydrate formation, along with their operational relevance. The structure of the dataset, the origins of the sensor measurements, and the labeling of instances have been reviewed in order to inform feature engineering and model development strategies. Several supervised learning methods – including k-Nearest Neighbors (KNN), Decision Trees (DT), Random Forests (RF), and Artificial Neural Networks (ANN) – have been implemented and compared. Additional classifiers such as Support Vector Machines (SVM) and ensemble boosting methods have also been used to evaluate classification accuracy and robustness. In parallel, time-series modeling techniques have been applied to capture the temporal dependencies present in sensor data. Approaches such as recurrent neural networks (e.g. LSTM autoencoders) have been examined for their ability to predict the early stages of events based on time-dependent sensor information. To support the development of realistic time-series models, simulated datasets have been transformed using autoencoder-based distortion techniques. These distortions have been learned from real well signals and applied to simulated data in order to preserve the dynamic characteristics of operational behavior while introducing realistic anomalies. Recurrent neural network models, including Long Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) architectures, have been applied under both multiclass classification and regression-based frameworks. In particular, a regression-based approach has been used to forecast class transitions by treating normal (class 0), transient (class 101), and anomaly (class 1) states as sequential time steps—representing past, current, and future behavior. This structure has been designed to simulate the natural progression of events in the wells. Instead of directly classifying the well state, the model has been trained to predict a numerical value representing the next probable class, which has then been post-processed and mapped back to discrete class labels. By adopting this method, a forward-looking prediction of system behavior has been made possible, offering the potential for earlier anomaly detection. The findings highlight the advantages of integrating supervised classification with time-series modeling and realistic data transformation. The combination of these methods has contributed to a more complete understanding of offshore well conditions and provided a practical foundation for building intelligent systems capable of monitoring operations and supporting decision-making in oil production environments
THREE ESSAYS ANALYZING THE IMPACT OF GLOBALIZATION ON MEXICO'S DEVELOPMENT
No full textThe first chapter studies the impact of the U.S-Mexico avocado trade on Mexico's crime. The grip of drug cartels in Mexico casts a dark shadow over the nation, fueling rampant violence, fierce territorial disputes, and widespread regional instability. Mexican politicians and international spectators alike are becoming increasingly aware of a troubling trend: cartels are diversifying their operations into the avocado industry, a lucrative market they exploit to finance their violent agendas. Using data from 460 Mexican municipalities over the period 1997 to 2019, this study exploits exogenous weather changes in U.S. avocado-producing regions to show that increased Mexican avocado producer prices decreased homicide in Mexican municipalities more climatically suited to grow avocados, likely due to increased agricultural employment there. However, after the War on Drugs began in 2006, higher avocado prices \emph{increased} homicide, property crime, and cattle theft in those same municipalities. This time heterogeneity likely stems from drug cartels more aggressively diversifying their portfolios to the avocado industry to fund violence against Mexico's government and competing cartels. The second chapter investigates how U.S.-Mexico avocado trade has affected Mexico's surface water quality. This chapter provides empirical evidence that the 2016 Mexican Hass Avocado Import Program amendment led to improved water quality likely due to Mexican avocado farmers incorporating cleaner production methods and applying less harmful pesticides to their avocados. Two-way fixed effects difference-in-differences analysis shows that the policy improved surface water quality, reducing biochemical oxygen demand (BOD) by approximately 12 percent and chemical oxygen demand (COD) by 11 percent. The third chapter examines the impact of foreign direct investment inflow on Mexico's gender wage gap. There is an ongoing discussion of the numerous effects of trade openness on Latin America’s economy. In this study, I evaluate the impact of the Mexico-EU Free Trade Agreement (FTA) of 2000 on Mexico’s gender wage gap. For Mexico, the policy encouraged FDI inflow from Europe; however, 91.5 percent of this FDI went to the Mexico City Federal District or the states of Mexico, Nuevo Leon, Jalisco, and Puebla. FDI inflow tends to benefit foreign manufacturing companies' wages in the host country. I use survey data from 1995 to 2004 and apply a difference-in-differences model to assess the policy's effect on gender wage inequality. The empirical findings indicate an increased disparity in men’s average monthly earnings and hourly wages compared to women after the enactment of the trade policy in these 5 states. The empirical evidence also indicates no change in the average hours worked by both genders after the policy. The findings suggest that one contributing factor to the increase in the gender wage gap in this region may be the highly concentrated inflow of foreign direct investment from the European Union
Application of Nuclear Magnetic Resonance to Investigate Enhanced Oil Recovery and Geostorage of CO2 and H2
No full textThe global energy transition demands innovative technologies to address growing energy needs while mitigating environmental impact. Nuclear Magnetic Resonance (NMR) relaxometry has emerged as a powerful tool for characterizing reservoir properties and fluid behavior, offering significant potential for applications in enhanced oil recovery (EOR), carbon capture and storage (CCS), and underground hydrogen storage (UHS). This study explores the capabilities of NMR in addressing the critical challenges associated with these energy transition technologies.First, NMR was applied to evaluate fluid recovery during Huff-n-Puff (HnP) EOR in shale reservoirs on preserved samples from the Eagle Ford and Wolfcamp using a mixture of C1:C2 (72:28) gas. Pressure stepped saturation using 2.5% KCl brine and dodecane was used to understand organic versus inorganic pore throats connectivity. Results show that oil production in Eagle Ford and Wolfcamp formations using C1:C2 (72:28) is primarily driven by the vaporization of lighter hydrocarbons (below C₁₃), while free water production is controlled by wettability and pore connectivity. The Eagle Ford formation exhibited continuous oil production (25% recovery) and moderate water recovery (15%), attributed to its well-connected organic pore network (pseudo parallel connectivity). In contrast, the Wolfcamp formation, characterized by high clay content (serial flow connectivity), showed limited oil recovery (10%) and higher water recovery (27%), with episodic water breakthrough after early oil production. These findings highlight the critical role of pore structure and connectivity in governing recovery behavior during EOR. For CCS applications, NMR was employed to assess the integrity of Class G cement exposed to supercritical CO₂ (scCO₂). The results showed that scCO₂ exposure led to precipitation and dissolution of calcium carbonate, leading to a reduction of porosity from 37% to 33% over five weeks. Notably, diffusional tortuosity increased sixfold after two weeks but later decreased to threefold after five weeks, suggesting an initial sealing stage followed by a dissolution phase. The extent of reaction was found to be pore-size dependent: in smaller pores (<30 nm), carbonate dissolution dominated, while in larger pores (30–200 nm), both precipitation and dissolution were observed. These findings indicate that scCO₂ exposure can alter the flow path in cement, potentially limiting CO₂ migration and leakage over time. In the UHS study, NMR was used to investigate hydrogen solubility in organic and inorganic bulk fluids. Experiments revealed that hydrogen remains primarily in the free phase in water and hydrocarbons, with negligible solubility observed in dodecane, dead oil, and ozokerite wax. However, fluorinert HT-230 (used as confining fluid for NMR plug measurement) exhibited measurable hydrogen solubility (4–6 cc of H₂ per 100 cc of fluorinert at 1800 psi). Additionally, long-term experiments in cyclohexane demonstrated progressive hydrogen dissolution over 32 days, increasing the hydrogen index (HI) by 3.42%, confirming slow but measurable uptake. These results highlight caution during signal processing and interpretation using hydrogen gas. Further, NMR was applied to assess hydrogen storage in rocks, including organic-rich shales (Eagle Ford, Duvernay, Marcellus) and partially brine-saturated Berea sandstone. Results indicated that hydrogen occupied the entire pore network in shales, with minimal interaction with the organics and clays, regardless of maturity. In sandstones, hydrogen storage capacity was also directly proportional to available pore space, with no significant hysteresis observed, confirming full recovery potential. Overall, this study demonstrates that NMR provides critical insights into fluid transport, phase behavior, and storage mechanisms relevant to EOR, CCS, and UHS. By quantifying fluid-rock interactions with high precision, NMR enhances our ability to optimize energy storage and recovery strategies in the subsurface, contributing to the development of sustainable energy solutions
EXPLORATION OF CHAOTIC ORBITS IN THE NEPTUNE-TRITON SYSTEM FOR ENHANCED SPACECRAFT CAPTURE
No full textThis work examines chaotic regions of orbits in the Neptune/Triton system to affect Δv savings during spacecraft capture around Triton. The Neptune/Triton system is represented with an n-body model in a Neptunian Equatorial reference frame. The model includes the Sun, Neptune, Triton, and the J2 perturbation of Neptune and Triton. A matrix of Initial Conditions is analyzed to discover regions of chaotic motion using Perturbation Maps and orbital deviation methods. Once chaotic regions are located, a technique of evaluating the orbits of spacecraft by integrating time backward to an escape, then using the end state vector of the reverse time integration as initial conditions of forward integration of time to capture are run. This study shows where chaotic regions can be used to affect the capture of a satellite around Triton with less than zero two-body energy with respect to Triton, and hence less Δv than a traditional capture technique. Examples of the potential chaotic regions and the reverse and forward time integration capture trajectories are shown
Modeling of Inflation Rates and Mechanical Creation of Reflective Sphere to Harness Solar Radiation Pressure for Medium Earth Orbit Satellites
No full textThis study proposes a dynamic model for the trajectory of a non-functional satellite with an inflatable spherical solar sail that acts as a de-orbiting device by harnessing Solar Radiation Pressure (SRP) and varying area-to-mass ratios. The model mimics real-world behaviors by using equations of motion that feature natural perturbations and SRP calculations using the cannonball model and shadow function. The time needed for the proposed balloon to push medium Earth orbit space debris back into the atmosphere is calculated for various binary and linear inflation methods. The results indicate that for satellites in near-circular orbits with an initial semi-major axis of 22,000 km, the solar sail can be deployed to push them into atmospheric re-entry within about 34.96 or 50.14 years for initial orbital inclinations of 0.001 or 56.06 degrees, respectively. For a GPS satellite with a semi-major axis of 26,560 km and inclination of 55 degrees, de-orbiting occurs within 61.3602 years. There is a potential for the improvement of these times by using a larger balloon or more reflective material. Alternative materials and compressor specifications are explored, though future advancements in these technologies are required to prove the feasibility of a mechanical model
Advanced Organic Chemistry
No full textThis lecture slides set cover the fundamentals of organic structures, reactions, and mechanisms. This course is designed to instruct first-year graduate students who are interested in the research of organic chemistry. Topics include molecular structures and orbital theory, aromaticity and antiaromaticity, isomerism and stereochemistry, and active reaction intermediate.The University of Oklahoma Libraries' Alternative Textbook Gran