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An exploratory study of number sense acquisition in kindergarten : contributions of quantity recognition, ordinality, and counting
Full text linkThe current exploratory learning analytics study incorporated log-file data from an early number sense intelligent tutoring system: Native Numbers. The data, generated during a previous randomized wait-control study, included three competency indicators extracted from performance on Native Numbers’ five sets of quasi-summative assessment activities: an accuracy rate, the total number of tasks, and the highest level of difficulty reached for activities covering the concepts of quantity recognition, ordering, and counting. On the pre-test, a standardized and normed number sense screener, most of the 42 kindergarten participants performed at or above average. Nonetheless, the post-test scores indicated the two groups each significantly increased their performance after completing Native Numbers. Furthermore, only ten of the 29 items on the screener directly assessed concepts explicitly included in Native Numbers’ instruction; the participants appeared to generalize learning from Native Numbers’ to other concepts on the screener. The overall goal of the current study was to examine the participants’ data from the assessment activities and the responses to the items on the number sense screener, to discern possible explanations for the participants’ growth. The rational for the study was that understanding how above-average performing students increased their number sense could help inform how students who struggle with mathematics may increase their number sense. Analyses included nonparametric tests and generalized linear mixed effect logistic regression to examine if performance on the quasi-summative assessments predicted changes on the post-test; and, if the time of year of instruction was a factor in performance. Results indicated that participants had little variability in the levels of difficulty reached across the five quasi-assessment activities, some variability in their accuracy levels, and significant differences in the number of tasks they completed. Differences between the groups were not significant and the triad of performance indicators did not predict the likelihood of change on the number sense screener. One possible explanation is that log-file data performance indicators were not sufficient to predict change because all participants received both the instruction and the time needed to reach mastery. Why above-average performing participants generalized learning for concepts not included in Native Numbers remains unclear.Special Educatio
A spatiotemporal investigation of rainfall seasonality in Spain across the Pliocene-Pleistocene
Full text linkThe climate of the modern Iberian Peninsula (IP) is characterized by cool-wet winters and hot-dry summers, dubbed a Mediterranean-Type Climate (MTC), which is superimposed with a N-S latitudinal climatic gradient. Evolving from seasonally-muted subtropical conditions prior to Northern Hemisphere Glaciation (NHG), modern-like ecosystems on the IP established between 3.40 Ma – 3.25 Ma, concurrent with global cooling. To advance our understanding of the onset and evolution of the MTC across Spain we investigate two study areas: the NE Teruel Basin and the SE Guadix Basin. For NE Teruel, we present paleosol carbonate stable oxygen isotope records (δ¹⁸O[subscript c]) from 4.2 Ma – 2.4 Ma. The δ¹⁸O[subscript c] values show a negative excursion during the Marine Isotope Stage (MIS) M2 (~3.3 Ma) and a subsequent decrease during the intensification of the NHG (iNHG: ~2.73 Ma). Comparison to previously published proxy records of the region point toward the establishment of a summer drought season (less input of high-δ¹⁸O summer rainfall) as the cause for the negative δ¹⁸O[subscript c] shifts. To better constrain the hydroclimate changes associated with this δ¹⁸O[subscript c] record, we combine clumped isotope thermometry (TΔ₄₇), triple oxygen isotope data (Δ’¹⁷O), and modeled rainfall δ¹⁸O[subscript p] from a subset of Teruel soil carbonates to estimate formation temperatures and soil water isotopic compositions. This data provide evidence for a shift in the seasonal formation window of the soil carbonates from a warm-season bias (3.9 Ma – 3. 12 Ma) to a (largely) cool-season bias (3.12 Ma – 2.75 Ma) in response to a change in rainfall seasonality associated with an MTC onset. Comparatively, we present δ18O[subscript c] records of soil carbonates and palustrine limestones (δ¹⁸O[subscript PL]), constrained by a novel paleomagnetic age model, of the SE Guadix Basin from 3.7 Ma – 1.9 Ma. We find that the Guadix δ¹⁸O[subscript c] values are ~1.9‰ lower than samples from Teruel over 3.7 Ma – 1.9 Ma, which, when compared to regional proxy data, supports the existence of a summer drought in southern Spain by ~3.7 Ma. Together, these data provide evidence that the IP's hydroclimate is sensitive to global cooling events and there are likely different controls on Spanish climate in the north and south.Earth and Planetary Science
Non-intrusive methods for assessing microbial and chemical contaminants in residential buildings
Full text linkIndoor environments are where we spend nearly 90% of our time, and thus, exposures to the elevated contaminant concentrations frequently found indoors can impact our well-being and health. Dust samples from the floor and heating, ventilation, and air conditioning system (HVAC) filters can be used to investigate microbial and chemical contaminants within indoor environments. During the COVID-19 pandemic, indoor air quality was crucial to understanding and mitigating the spread of the virus. However, access to these spaces was often limited due to building occupancy restrictions and residents isolating at home. Non-intrusive methods of collecting indoor dust samples are helpful for investigating and monitoring these indoor spaces, particularly during public health crises. More broadly, the ability to efficiently collect and analyze samples from a wide variety of residences is needed to accurately assess our everyday exposures to the broad range of microbial and chemical contaminants present indoors. This dissertation details three studies conducted with the aim of evaluating non-intrusive techniques for residential dust collection and analysis to provide a more comprehensive compositional analysis of both microbial and chemical contaminants in the indoor environment. The first study investigates the use of community science and participant-collected samples as an alternative to researcher-collected samples, allowing building occupants to collect their own dust samples and ship them to the laboratory for analysis. The sampling kit developed in this study was also subsequently used to collect samples in a COVID-19-positive household to investigate SARS-CoV-2 concentrations at various locations within the home. The second study investigates the use of HVAC filter dust in centralized air handling units in multi-residential settings where far more occupants contribute to and are exposed to the indoor environment than in a single-family setting. Sampling from a centralized air handling unit (AHU) is potentially useful for identifying zones within a building to prioritize for further investigation rather than having to sample every individual residential space within these larger buildings. Finally, a third study explores the development of a method to explore a broader composition of chemical contaminants present in residential dust samples with PTR-ToF-MS, in comparison to traditional GC-MS methods. Together, these studies provide insights into indoor environmental contaminant detection, monitoring, and management strategies. With these techniques, participant-collected dust and centralized AHUs filter dust are used to efficiently investigate the microbial and chemical composition of single-family and multi-residence spaces. Information collected from studies such as these has been and can be used to identify more sources and drivers of microbial and chemical contaminants in residential environments. These insights are crucial for advancing our understanding of air quality in not only residential but all indoor spaces and for implementing effective strategies to promote healthier indoor environments globally.Civil, Architectural, and Environmental Engineerin
UT Symphony Orchestra Collection finding aid
No full textThe UT Symphony Orchestra collection spans nearly 40 years (1955-1991_ and includes original concert recordings, primarily on reel-to-reel tape with some content on VHS. Conductors represented in the collection include Alexander von Kreisler, Walter Ducloux, Cornelius Eberhardt, and A. Clyde Roller. A range of soloists are featured, including Gregory Allen, Paul Olefsky, Vincent Frittelli, Georges-Henri Pantillon and Susan Hickok. Many of the recordings have limited program information beyond the concert date.UT Librarie
Exploring the emotion of hope and how it impacts consumer choices through construal level
Full text linkThis dissertation explores the relationship between the emotion of hope and construal level in the context of consumer behavior domains of decision making and persuasion. An exploratory study determined that hope induces a more abstract construal level mindset compared to a control condition. An abstract construal mindset focuses on why a behavior is accomplished, compared to a concrete construal mindset, which focuses on how a behavior is accomplished. Study 1 sought to explore incidental hope’s relationship with construal level in a consumer decision making context. Participants rated their preference between two option choices, one high in desirability and low in feasibility (considered a representation of abstract construal level) and one high in feasibility and low in desirability (considered a representation for concrete construal level). Study 1 showed support for hope’s ability to induce abstract thinking, as hopeful participants (compared to a control condition) preferred a hotel option with high desirability and low feasibility over an option with high feasibility and low desirability. Study 2 focused on the compatibility between integral hope (a hope emotional appeal) and abstract construal (through desirable product features) in an advertising context. A 2 (emotional appeal: hope, control) x 2 (product feature emphasized: high desirability, high feasibility) between-subjects experiment was conducted, with participants viewing three advertisements from the same experimental condition. Advertising effectiveness was measured as the outcome. The results found no effect for the emotional appeal, the product feature emphasis, or their interaction on advertising effectiveness. Overall, this dissertation shows support for hope’s ability to induce an abstract construal mindset, as well as incidental hope’s ability to influence consumer option preference. There was no support for the compatibility of a hope appeal with high desirability product features in advertisements. The findings of the three experiments are discussed, along with practical implications, limitations, and future research.Advertisin
"Hell no, we won't go!" : Black draft resistance and grassroots prison organizing during the Vietnam War
Full text linkIn 1969, Walter Collins, a Black civil rights and anti-war activist, appeared in court on charges of draft evasion. The jury convicted Collins on five counts, and the district judge sentenced him to five years in prison. In response, Collins’ family members, colleagues, and other supporters mobilized on his behalf. They drew from existing networks and created new organizations like the International Committee for Black Resisters (ICBR) to support his legal defense and publicize his case. By examining Collins’ legal case and the dynamic campaign that developed around it, this report explores how the draft affected Black activists and, furthermore, how these activists navigated the criminal legal system and appealed their sentences. Drawing from newspaper articles, court records, oral histories, and organizational papers, I argue that defense campaigns around the cases of Black draft resisters were important sites where civil rights, anti-war, and prison organizing converged. Studying these grassroots efforts, alongside the critiques and arguments that participants developed, furthers our understandings of these movements.Histor
The operationalization of equity in the provision of water infrastructure services
Full text linkThe provision of water services in the US were designed to increase access to safe and reliable water for all populations. However, historic investments with regards to water sector services (e.g., 1974 Safe Drinking Water Act) limited access to certain populations, primarily racial minorities and low-income communities. Such disinvestments have cascading consequences, including water quantity issues (e.g., shut-offs) and water quality issues (e.g., lead contamination). Currently there is limited for integrating equity into the design and management functions of water providers. Similarly, there is a dearth of literature that explores practical equitable water infrastructure provision. By analyzing water providers perceived equity definitions, considerations, and barriers, practical paths forwards can be documented in literature. This dissertation examines the opportunities and barriers to operationalize equity in water provision services using three studies targeting different management functions of water providers – (1) day-to-day operations (2) adopting new technology (3) communicating during disasters. Currently, how equity is defined in water-sector infrastructure services is inconsistent across literature and practice, making it challenging to hold water providers accountable to achieving equity. Therefore, as a first step, survey, interview, and media data are used from water providers across the US to define equity. From this dataset common considerations and stated barriers to equity were analyzed, and key thematic codes emerged to supplement the definition. Next, the second study examines how equity can be incorporated in the process of adopting new water technologies. An equity framework for the implementation of building-scale onsite non-potable water systems is developed. This was accomplished using interview data from subject matter experts in San Francisco and New York where such systems are actively being adopted, however still lack regulatory frameworks that incorporate equity. Lastly, the final study examines the equity implications of social media communications by water providers during a protracted crisis, the COVID-19 pandemic. Twitter data from water utilities during the pandemic was analyzed to identify whether equitable communication occurred between utilities and end-users. This was measured by interactions with social media posts written in multiple languages and those discussing financial assistance in disadvantaged communities. This dissertation provides practical and theoretical contributions to help shape how water providers, community organizers, policy makers, and disaster managers approach and operationalize equity in the water sector as part of their daily functions. For instance, results show that some respondents indicated that they do not consider equity at all, making the implementation of equity in their functions challenging. Others stated that they did not understand how the socio-demographic fabric of their communities can serve as a technical metric in their design and management processes. This dissertation captures such perceptions and synthesizes them for both practical and theoretical applications to assist organizations in improving their equity efforts.Civil, Architectural, and Environmental Engineerin
When the healer is sick and tired : antecedents of psychosomatic symptoms in minority medical students
Full text linkDue to a significant dearth in extant literature, the purpose of this study was to explore psychosocial precipitants of psychosomatic symptoms in racial and/or ethnic minority medical students. This study was exploratory in nature, as very few researchers have examined possible contributors to the mental and physical health of this population. Secondary goals of this study included an examination of (1) between-group differences in reports of medical school stressors and psychosomatic symptoms (2) the association between racialized stressors and psychosomatic health and (3) the association between psychosomatic symptoms and suicidal ideation. Participants included a sample of 320 African American, Asian American and Latinx American medical students. Results indicated (1) that racialized stressors were significant contributors to psychological distress, somatic distress, and burnout, over and above the normative stressors associated with medical training (2) that significant between-group differences in reports of minority status stress and perceived discrimination were found, such that African American medical students reported significantly higher rates (3) that significant between-group differences in reports of psychosomatic symptoms were found, such that Asian American medical students reported significantly higher rates of psychological distress, anxiety, and depression, while African American students reported significantly higher rates of burnout and (4) that burnout, psychological distress, and somatic distress were significant predictors of suicidal ideation, with somatic distress serving as the strongest predictor. Theoretical and practical implications of these findings are discussed.Educational Psycholog
Advancements in single- and multi-target filtering : using posterior estimates to update Gaussian mixture weights
Full text linkA major focus of this thesis is on computing the weights of Gaussian mixtures for single- and multi-target filtering methods alike. Computing the weights is a crucial part of the filtering process because they determine the contribution of each Gaussian mixture component to the overall distribution. Traditionally, weights are approximated by linearizing the nonlinear measurement model about the prior estimates. But, in nonlinear measurement scenarios, using the prior estimates to compute the weights is only an approximation, and one that ignores the latest information available, which can lead to subpar filtering performance and inconsistent state estimates. Therefore, this thesis argues that the weights should instead be computed using posterior estimates because the posterior provides a better characterization of the system after receiving the latest measurement data. In this thesis, some new weight formulations using posterior estimates are proposed, as well as a new kernel-based multi-target filtering algorithm. The organization of this thesis is structured such that each chapter builds off one another, telling a cohesive story.Aerospace Engineerin
Three essays on nuclear proliferation
Full text linkFar from fading with the end of the Cold War, the specter of nuclear weapons proliferation continues to loom as nuclear-armed states attempt to prevent their spread. States like Iran and North Korea continue to pursue or improve their nuclear programs. Yet others with the technical capacity to acquire such weapons with relative ease, like Japan or Brazil, have chosen to refrain from doing so, but continue to maintain their “almost nuclear” status in lieu of further developing or dismantling their programs, suggesting that there are benefits beyond those accruing only to states with a working weapon. Further, states that do acquire nuclear weapons may use them strategically in ways that are not always as straightforward as one might expect, such as Israel’s “Samson Option” or South Africa’s strategy of “catalytic deterrence.” These circumstances call for a broader examination of the proliferation process, as states may be able leverage their nuclear capability in ways that consider how their development is likely to influence not just opponents, but also potential protectors, in the future. To consider the motivations for nuclear capability, in this project I take a more expansive view of nuclear power beyond weapons possession and potential use alone. I look at the relationships between proliferators and their allies, as well as their adversaries, considering how those relationships may shape and be shaped by decisions in the nuclear sphere.
First, I consider the effect of nuclear weapons acquisition on the reliability of great power protectors. In addition to the natural deterrent effects typically ascribed to nuclear weapons possession, I show that in some cases, acquisition can draw a great power patron closer and make a previously incredible commitment credible. When patrons also expect to pay increased costs for a nuclear-armed ally’s participation in a war, their incentives may be changed, such that they may prefer to come to that ally's aid where they would otherwise choose abandonment in the absence of a nuclear weapon. Consequently, states contemplating nuclear pursuit may take into account the potential such weapons have to tighten an alliance relationship in times of war. This increased reliability of a patron’s protection could improve a state's chances of prevailing in a conflict, but it could also increase the deterrent power of the alliance, suggesting further, less directly observable benefits of acquisition. In this way, nuclear weapons’ ability to rearrange patron preferences creates a new incentive for proliferation, complementing and compounding the benefits of an improved military capability of one's own.
Second, I look at nuclear latency as a strategy in its own right, in order to consider the incentives for states to remain near the nuclear threshold without crossing over it. I show that states may begin nuclear programs for the purposes of improving their bargaining position, even if they know that actually acquiring a weapon is beyond their reach. By considering both that nuclear programs have ongoing costs and that a latency capability may itself be a goal, rather than a stepping-stone along a path leading directly to weapons acquisition, I show that the bargaining concessions offered to states on the brink of acquisition may also be available to those states whose capabilities fall slightly shy of that threshold. Buying off these less-capable states can still be in a bargaining partner’s best interests if doing so would also buy off a truly capable proliferator. States may move along the proliferation path but plan to stop shy of weapons acquisition, showing not only that “almost nuclear” status can have bargaining benefits, but also that these benefits themselves may be the goal. Because of this incentive, there may exist a population of states for whom nuclear progress to the point of latency is a viable strategy, even in the face of prohibitive costs for a weapon. This strategy can also allow states with high levels of technical capacity to commit to reining in their own nuclear pursuit short of a weapon while maintaining a credible threat to acquire one, allowing them to receive the bargaining concessions such a weapon would bring without becoming more immediately threatening to their opponents. In this way, latency can help stave off preventive wars while still allowing highly-capable states to bargain as such.
Finally, I look at what affects states’ movements into and out of latency, as well as from latency into nuclear weapons possession. Since nuclear latency itself can have benefits, and since nuclear weapons come with costs, we should not assume that all who begin a nuclear program will necessarily attempt to develop that program into a weapon. The motivations for beginning a nuclear program and acquiring a nuclear weapon can differ in important ways, and therefore we should expect the factors affecting them to also differ significantly. Further, states can and do reverse existing programs, choosing to move away from nuclear weapons rather than toward them. By considering the steps of nuclear proliferation as a process through which states may choose to move, rather than considering program initiation or weapons acquisition in isolation, I show that the effects of security variables on proliferation differs in interesting and sometimes unexpected ways when progress and reversals are considered as part of the same, integrated process.
Together, the project argues for a careful study of the less-explored aspects of what it means to pursue and possess nuclear weapons and for the need to consider the proliferation path in its entirety. Beyond the deterrent or defensive benefits a state expects to accompany weapons possession, there are less obvious but no less important consequences that can accrue at different points along the process, from the bargaining concessions that may accompany a latent capability, to the potential tempering of the incentives for preventive strikes against a nuclear-adjacent power, to the possibility of improving a patron’s reliability via acquisition. Improving our understanding of these benefits should also inform how we approach empirical studies of the determinants of nuclear proliferation, as a process with differing and sometimes countervailing effects of the same factors at different steps along the way. In this project, I examine some of these more indirect benefits of nuclear pursuit and begin the work of taking a more integrated approach to the empirical study of the process in light of these new considerations.Governmen