• 

  Utilizing a Reminder To Improve Childhood Obesity Screening in Native American Children

  Kiser, Lisa H.; Newton, Tarnia; Gutierrez, Kirby Ann; Nechiporenko, Claire (The University of Arizona., 2024)

  Improving the screening and management of childhood obesity among Native American children is critical in addressing the significant health disparities in this population. This quality improvement project implemented a pediatric obesity screening reminder and provided targeted education to healthcare providers. Childhood obesity is a significant public health concern, with the Native American population being disproportionately affected. The quality improvement project measured the impact of the two interventions through pre- and post- intervention self-administered questionnaires and chart audits. The findings showed a slight increase in the detection rate of obesity at well-child visits and increased referral to the registered dietitian (RD). However, there were issues, such as culture, practicality, and patients’ involvement. The outcomes of the project demonstrated that the interventions were effective in increasing the rate of obesity screening and RD referral, but highlighted the need for another PDSA cycle with modifications. The results of the project revealed that childhood obesity is not easily manageable, especially where the community is culturally diverse. A higher rate of declined RD referrals further necessitates enhanced engagement strategies such as improved patient education, motivational interviewing, and family involvement. Subsequent endeavors should include collaborating with obesity specialists and community resources. Providing walk-in or same day access to the RD and increased telehealth services can also assist in navigating logistical challenges that may hinder families from receiving initial and ongoing nutritional education.
• 

  Understanding the Stellar Mass Growth and Quenching of Massive Galaxies

  Rieke, Marcia; Woodrum, Charity; Kennicutt, Robert; Hainline, Kevin; Egami, Eiichi; Straughn, Amber (The University of Arizona., 2024)

  One of the first remarkable studies in the field of galaxy evolution determined that there are two distinct types of galaxies based on their morphologies: spirals and ellipticals. We’ve since found that spirals tend to be blue, lower-mass, gas-rich, star-forming galaxies. On the other hand, ellipticals tend to be red, massive, gas-poor, quiescent galaxies. This “galaxybimodality” is still being studied today, as we have many unanswered questions about the origin of its existence. For example, how do star-forming galaxies grow in stellar mass? And what physical processes are responsible for the cessation of star formation in quiescent galaxies? In this dissertation, I explore the stellar mass growth and quenching of massive galaxies. I use a sample of high redshift (6.7 < z < 13.2) galaxies to study how varying the initial mass function (IMF) changes their inferred stellar masses, showing that a redshift-dependent IMF infers reduced stellar masses in the high redshift universe. Next I explore the heterogeneity ofmolecular gas reservoirs in quiescent galaxies, showing that quiescent galaxies with detectable gas reservoirs have evidence of secondary bursts of star formation, likely driven by gas-rich minor mergers. Furthermore, I explore the connection between active galactic nuclei (AGN) activity and suppressed star formation, and show that even with high quality data and gold-standard star formation history (SFH) modeling, it is difficult to find observational evidence of AGN-driven quenching. Finally, I investigate the star formation and chemical enrichment histories of massive, quiescent galaxies as a function of their structural and environmental properties, finding that galaxies are quenched through a complex interplay of physical mechanisms.
• 

  Undergraduate Research and Students with Learning Disabilities: Tensions Between the Exclusivity And Promise Of The Experience

  Rhoades, Gary; Mason, Laurel; Kraus, Amanda; Haeger, Heather (The University of Arizona., 2024)

  Undergraduate Research (UR) is a high-impact practice that results in positive outcomes for participants, such as improved academic skills and intellectual development as well as higher graduation rates and graduate school attendance. This research project compares the UR participation patterns of students with learning disabilities (LD) and their experiences engaging in UR settings to the signals displayed on UR websites. The project utilizes a mixed-methods design comprising four data sources and several analytical methods: content analysis of UR websites, quantitative analysis of institutional UR course data, and quantitative and qualitative analysis of survey data from 50 LD students and interview data from 4 LD students. UR websites feature text and imagery associated with prestige (achievement and competition), personal investment (commitment and unique benefits), and STEM fields. Students’ perceptions of UR participants and their course taking patterns mirrored those signals in some ways but not others. Students viewed UR as an activity for smart students who are involved and good at school, and the majority of actual participants were high achieving. Survey and interview respondents corroborated the benefits listed on UR websites. While participants with LD were underrepresented as UR participants, they reported positive experiences in UR settings, Their LD impacted their work to some extent, yet none disclosed their disability status or requested accommodations to avoid the stigma associated with learning disabilities. Non-participants with LD reported a lack of awareness, time, and confidence as the main reasons for not participating. These findings indicate the need to revise and expand the signals about UR to define it as an active learning process for students in all fields of study, not just STEM. Website content and outreach should specifically include representation of students who do not fit the traditional, high achieving norm. Additionally, faculty and staff should receive training on bias related to disability, Universal Design for Learning to create a more inclusive experience for LD students. Lastly, other university personnel and peer ambassadors should be trained to promote UR experience to a wider range of students.
• 

  Transitional Shock Wave Boundary Layer Interactions and Surface Heat Transfer on a Hollow-Cylinder/Flare at Mach 5

  Threadgill, James A. S.; Roskelley Garcia, Alejandro Hamilton; Little, Jesse C.; Craig, Stuart A. (The University of Arizona., 2024)

  A hollow-cylinder model with a 15◦ half-angle flare is tested at Mach 5 for fivedifferent Reynolds numbers ranging from 4.10 × 105 < ReL < 1.62 × 106 . The laminar boundary layer separates due to the shock-induced pressure rise and reattaches downstream of the flare corner. Reattachment is associated with transition to turbulence and the formation of hot streaks. Surface heat transfer is measured using a FLIR infrared camera and five custom Ahmic thin-film gauges while pressure fluctuations are measured with two Kulites and three PCBs. For sufficiently transitional cases, heat transfer reaches a maximum near reattachment and moves upstream for increasing Reynolds number. Steady heat transfer trends along x/L between IR and thin-film gauges match qualitatively and the discrepancies between each diagnostic are discussed. In the premultiplied pressure spectra, two peaks were identified at f ≈ 14 kHz and f ≈ 100 kHz and their potential sources are discussed. Unsteady heat transfer measurements are discussed in regards to their viability for detecting reattachment and transition.
• 

  Traditional and Novel Hippocampally Mediated Cognitive Tasks in Typically and Atypically Developing Youth

  Edgin, Jamie O.; Lovos, Annalysa Kelly; Tzuyin Lai, Vicky; Andrews Hanna, Jessica (The University of Arizona., 2024)

  The hippocampus is known to help in the recall of associations and episodes from the past. This is a form of mental representation, and other forms of mental representation may be associated with the hippocampus as well. Five candidate complex cognitive functions involving suspected hippocampal involvement are discussed in the theoretical part of this dissertation, and a case is made for integration of the hippocampus into developmental theory. As the hippocampus is a gradually developing structure, we must consider how its slow course affects the development of cognitive functions that seem to involve it, at various stages. Following on this call to update developmental theory with integration of the hippocampus to account for a broad range of representational cognitive processes in Chapter 2, I introduce preliminary models in Chapter 3 in which I seek to test this for the case of creativity. Forty-three youth participated in cognitive data collection (21 with Down syndrome), and 38 of these participants (18 with Down syndrome) also underwent MR imaging. In modeling creativity as a function of memory and executive control, I seek to discover the extent to which memory contributes to creativity. Significant results were found for the group with Down syndrome, with associative memory and executive function emerging as predictors of creative performance. Surprisingly, these associations were absent in the typically developing group, for which the model and the variables were not significant. I also predicted that creativity and adaptive behavior would be positively correlated as representational functions that seem to have mnemonic contributions. Results included a positive correlation for creativity and adaptive behavior in the group with Down syndrome, while these functions were negatively correlated in the typically developing sample. In Chapter 4 I turn to examining the hippocampus itself. Previous studies have examined the hippocampus at the level of its subfields in adults with Down syndrome but not in youth, and while automated segmentation studies have been done with typically developing youth, there is little information on whether automated and manual methods agree for this age group. In the current study, subfield segmentations were made for youth with Down syndrome and typically developing youth using both methods in order to determine what group differences characterize the development of subfields, how well the methods concur with typical and atypical samples, and whether specific subfields relate to specific cognitive functions. The two methods showed small to moderate correlations across the subfields tested. The anterior hippocampus was correlated with associative memory in both groups and the CA1 subfield with adaptive behavior in both groups. Creativity did not show a correlation with hippocampal subfield volumes. Altogether group differences were more profound than expected in the studies described in chapters 3 and 4. Creativity, putatively linked to the hippocampus in Chapter 3, was well described by memory and executive control in the DS sample only. Possible explanations for this difference and the directionality difference between groups in the creativity to adaptive behavior study are offered. In Chapter 4, volumetric results largely supported hypotheses, but the methods produced less similar segmentations than anticipated, suggesting that continued caution is warranted in using automated methods with youth and special populations. Memory was similarly correlated with anterior hippocampus in both groups, but CA1 was only significantly related to CA1 in the DS group after correction, and creativity as a whole bore no significant relationships to subfields, although the creativity domain of flexibility was significantly related to CA and DG subfields in typically developing youth. In total, this dissertation explored hippocampal development and the concurrent development of “hippocampal” representational skills. More work is needed in order to understand how the developing hippocampal subfields interact with other brain regions and networks, how this changes across developmental time and how it may differ in various models of hippocampal impairment.

View more