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An exploratory study of number sense acquisition in kindergarten : contributions of quantity recognition, ordinality, and counting
Get PDFThe 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
Get PDFThe 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
Get PDFIndoor 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
More than sum of its parts : investigating episodic memory as a multidimensional cognitive process
Get PDFThere are many events we experience in our daily lives, only some of which we later remember. It remains unclear why some events are better remembered than others. While there have been numerous studies attempting to predict memory success using brain activity recorded from electroencephalography (EEG), memory prediction success has been mediocre. In this dissertation, I aimed to improve our ability to predict memory success by investigating the multiple underlying processes involved in encoding. Specifically, in Study 1, I optimized neural classification methodology to more accurately predict memory performance. Even though choosing the optimal classification methodology improved the performance, there remained room for further improvement. Along these lines, memory is a multidimensional process in which various cognitive functions contribute to memory formation. Consequently, in Study 2, I measured the contribution of visual perception, sustained attention, and selective attention (i.e., the “sources”) to encoding-related activity. I recorded EEG while 47 participants performed perception, sustained attention, selective attention, and episodic memory tasks. For each source, I designed a high vs. low performance classifier and leveraged the information about the brain states associated with low and high levels to predict memory performance from encoding-related brain activity. Results showed that this multidimensional assessment of the underlying processes happening during encoding improved memory decoding performance relative to evaluating episodic encoding as a unidimensional process. While the prediction performance improved, questions remained about the variation of involvement of these cognitive functions over time, over spatial location, based on time-on-task, and the encoding success history. Investigating these questions, in Study 3, I found successful encoding was associated with higher levels of each source than unsuccessful encoding regardless of encoding time period. As time-on-task increased, neural evidence associated with high levels of each source decreased, suggesting possible increases in fatigue and/or efficiency. Furthermore, the involvement of these cognitive functions fluctuated depending on the previous event’s memory success. Together, these studies provide invaluable insight into the underlying characteristics of successful memory encoding.Psycholog
The Dominant Major-Ninth Chord in Treatises and Textbooks
Get PDFIn connection with my blog On the Dominant Ninth Chord, I read in and put up posts about a number of treatises and textbooks. These posts are gathered here, with some additional material focused on repertoire. The survey is meant to complement my documentation of the treatment of the dominant major-ninth chord and the upper tetrachord of the major keyMusi
The homeless civic society : a study of liminal citizenship
Get PDFIn the seemingly exceptional American democracy—a country that prides itself as a beacon of progress, technology, and prosperity—millions of Americans experiencing homelessness are deprived of the most basic human needs of shelter and safety and subjected to severe economic, social, and civic exclusion. Existing approaches to this problem address the economic exclusion of people experiencing homelessness but fail to attend to their civic exclusion. This dissertation offers an alternative by exploring the potential contribution of civic participation in addressing homelessness. Considering homelessness as a civic and political problem comes to terms with the severe civic exclusion it entails. Despite being legal citizens, people experiencing homelessness are commonly excluded from enacting their citizenship or from any meaningful participation in civic, democratic life, and are considered unworthy of civic belonging. As such, they occupy what I refer to as liminal citizenship. In this dissertation, I ask how civic participation contributes to alleviating homelessness and explore how homeless individuals negotiate their liminal citizenship through daily practices of civic participation. Based on rhetorical field methods — including six months of ethnographic fieldwork and rhetorical analysis of homeless advocacy products — I explore the communicative dynamics between various housed and homeless actors and analyze their public rhetoric. Specifically, I ask what homeless individuals do to participate civically and discuss how they come to acknowledge the structural causes of their homelessness, form a shared identity, maintain social support networks, leverage their embodied knowledge, and advocate for their community. My findings indicate that civic participation is a site where homeless individuals continuously negotiate their liminal citizenship — where they are subjected to social powers and discourses while also re-affirming their civic agency. Participating civically, they undergo a process of “political healing” that facilitates restoring a diminished sense of civic efficacy and agency. Their participation grants homeless individuals a sense of meaning and belonging lacking in existing housing solutions and therefore promotes homing rather than just housing.Communication Studie
Resource allocation & estimation algorithms for improved positioning in wireless OFDM networks
Get PDFPrecise and robust positioning is a key technology enabling the next generation of connected devices, intelligent vehicles, and air mobility platforms. To achieve the high precision demands of these applications, devices are increasingly focusing on the use of orthogonal frequency-division multiplexing (OFDM) signals due to their widespread availability in existing cellular network infrastructure and efficient spectral usage. However, traditional positioning methods rely on the presence of known reference signals which the user may correlate against. While existing cellular OFDM signals contain such reference signals, increased positioning accuracy may be desired and require resources or power to be diverted from the communication link, thereby decreasing data throughput. This tradeoff in communication throughput and positioning accuracy can be balanced through intelligent resource allocation and through estimation algorithms that exploit data resources without requiring the allocation of additional reference signals.
This dissertation is divided into three studies. The first study explores the design tradeoffs of OFDM signals used for both communications and ranging using traditional estimation techniques. The second study analyzes how the power and resource allocations of OFDM signal can be efficiently optimized to minimize ranging errors. The third study proposes bounds, estimators, and signal design strategies for exploiting data resources in time-of-arrival estimation, improving positioning accuracy without the allocation of any additional reference signals and minimizing overhead requirements by the network.Electrical and Computer Engineerin
Veteran teachers' perceptions of novice teacher types and their impact on working conditions in a high-poverty urban school district
Get PDFThis qualitative case study explored how veteran teachers perceive novice teachers and how the presence of novice educators influences their working conditions in high-poverty secondary schools, because much of the existing research on teacher turnover focused on novice educators and the factors contributing to novice teacher attrition rather than the effects of the increasing presence of novice teachers on veteran educators in high-poverty secondary schools. The research was carried out in the North Texas School District (NTSD) secondary schools, a large, urban public school district known for ongoing high teacher turnover rates. The teacher turnover problem had worsened in the aftermath of the COVID-19 pandemic, not only in NTSD but also across the state. As a result of widespread staffing shortages, urban schools increasingly depended on alternatively certified or non-certified novice teachers with limited pedagogical training or experience in urban school settings. A single large and urban school district, NTSD, bounded the qualitative single-case study. The data collection was guided by six domains of the workplace conditions framework developed by Leiter and Maslach: workload, control, reward, community, fairness, and values. The application of interpretivist epistemology also immersed me in the participants' subjective experiences during analysis. Semistructured interviews represented the primary source of data collection. The interview protocol was used to gather detailed narratives from the veteran teacher participants.
Along with interviews, institutional documents related to teacher retention data, professional development records, and school policies were reviewed to gain a contextual understanding of the veteran teachers’ data and support data triangulation. Interview transcripts were analyzed using deductive coding to ensure alignment with the study’s workplace conditions framework, while inductive coding allowed for the emergence of unanticipated themes directly from participants’ responses. Six main themes emerged that depicted how secondary school environments rely on veteran teachers to uphold school culture, maintain instructional consistency, and adapt continuously with limited systemic support. Theme 1 addressed novice teacher preparedness and entry pathways. Theme 2 referred to classroom management and professional boundaries. Theme 3 focused on veteran identity, professionalism, and retention. Theme 4 described the impact of novice teachers on veteran workload. Theme 5 examined shifts in student behavior post-COVID and their effects. Theme 6 highlighted policy and legal mandates that worsen veteran teacher workloads. The study offers implications for policymakers, school districts, and school leaders, along with recommendations for future research.Educational Leadership and Polic
Understanding school based mental health professionals' experiences post Covid-19 with African American and Latinx adolescents
Get PDFAfrican American and Latinx adolescents are disproportionately impacted by mental health wellness due to social and external factors, such as exposure to poverty and a general lack of access to resources, including mental health resources. Mental health challenges adversely impact these communities in a way that other racial and ethnic groups do not experience. Yet, little is known about whether school-based mental health professionals (SBMHP) are well equipped to deal with the current mental health challenges experienced by youth in schools. Thus, the purpose of my study is to analyze how SBMHPs, which includes social workers, psychologists, and psychiatrists, feel the training they receive equips them to address the current mental health needs of African American and Latinx youth, post Covid-19. With this focus, the reality of the impact of social and cultural mental health challenges can inform future training and development of SBMHPs.Educational Leadership and Polic