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"I have no idea really what's going on": teachers' self-efficacy and executive function implementation during the COVID-19 recovery year
No full textBarnes, Tia N.This thesis examines teacher perceptions of their self-efficacy in implementing executive function instruction during the 2020–2021 school year, described here as the COVID-19 recovery year. Executive function skills—including inhibitory control, emotional control, working memory, cognitive flexibility, and organizational skills— are often supported through consistent classroom routines. The disruptions caused by the pandemic required teachers to rebuild these routines across in-person and virtual settings. These disruptions resulted in challenges that could potentially influence teacher self-efficacy. Using teacher self-rating and qualitative interviews, this study explored how learning environments influenced teacher perceptions of self-efficacy in supporting student executive function development. Findings suggest that the classroom setting and teacher perceptions of self-efficacy influenced executive function instruction, particularly in the domains of emotional and inhibitory control. Student-teacher relationships emerged in the qualitative data as a key support for teacher self-efficacy, aligning with existing literature (Boe et al., 2008; Sharpe & Strosnider, 2022). These results indicate that, beyond instructional mode, multiple factors shape teacher self-efficacy in executive function instruction, extending the relevance of these findings beyond the COVID-19 context.University of Delaware, Department of Human Development and Family SciencesM.S
Where the sidewalk starts: the effects of privatized development on local political behavior in U.S. rural communities
No full textRedlawsk, David P.This dissertation draws on fieldwork across two U.S. counties—Huntingdon County, PA and Litchfield County, Connecticut—to explore the effects of privatized development on local political behavior in rural communities. Employing in-depth, semi-structured interviews and archival research, I show how for-profit development in rural communities can have economically, politically, and socially divisive repercussions for rural residents—particularly along class lines. Throughout my research, such polarization not only dictated where residents lived geographically, but also determined who had access to local political resources and decision-making structures. I further couch these findings in a broader analysis of capitalism, detailing the manner in which capitalistic logics tend to inform rural development processes, neoliberal governance within rural communities, and rural residents’ engagements with local political institutions. Collectively, I endeavor to describe how rising socioeconomic inequality and sociopolitical polarization across rural America can be catalyzed through private development efforts—arguing that this relationship perniciously limits rural working-class residents’ local political agency.University of Delaware, Department of Political Science and International RelationsPh.D
VERTICAL MOTIONS IN THE SOUTHERN OCEAN
No full textenterVertical motions (upwelling and downwelling) play an essential role in the
vertical transport of oceanic properties and materials. While past studies have reported
intense upwelling and downwelling in the Southern Ocean, a comprehensive analysis
dedicated to these vertical motions in the Southern Ocean remains to be accomplished.
Here, we analyze vertical velocity estimates in the Southern Ocean from the ocean
synthesis product ECCOv4, focusing on its spatial and temporal variability. We find a
general upwelling pattern from the Antarctic continent to around 55 °S and increasing
average vertical velocity estimates with increasing depth and near bathymetry features,
the Antarctic perimeter, and rough topography. Large temporal variations are observed
around the perimeter of the continent and near large bathymetric features (e.g., the
Campbell and Kerguelen Plateaus). Exploring links between interannual variations
and climate modes reveals a statistically significant moderate positive correlation
between vertical velocity and SAM from Antarctica to around 60 degrees S and a
negative correlation from 60 degrees S and northward. The results also show a
moderate negative correlation between the Niño3.4 Index and vertical velocity in most
of the Pacific sector of the Southern Ocean from Antarctica to 50 degrees with some
positive correlation northward of 50 degrees S. This study has implications that ENSO
and SAM could be anticorrelated and have opposing effects on vertical velocities in
the Southern Ocean. These results also confirm the connection between intense
vertical motions and topography. This paper builds on previous work by illustrating
how local dynamics in the Southern Ocean affect vertical motions and may have
implications for the climate system.ente
An active inference account of stuttering behavior
No full textThis article was originally published in Frontiers in Human Neuroscience. The version of record is available at: https://doi.org/10.3389/fnhum.2025.1498423
© 2025 Usler. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) (https://creativecommons.org/licenses/by/4.0/). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.This paper presents an interpretation of stuttering behavior, based on the principles of the active inference framework. Stuttering is a neurodevelopmental disorder characterized by speech disfluencies such as repetitions, prolongations, and blocks. The principles of active inference, a theory of predictive processing and sentient behavior, can be used to conceptualize stuttering as a disruption in perception-action cycling underlying speech production. The theory proposed here posits that stuttering arises from aberrant sensory precision and prediction error dynamics, inhibiting syllable initiation. Relevant to this theory, two hypothesized mechanisms are proposed: (1) a mistiming in precision dynamics, and (2) excessive attentional focus. Both highlight the role of neural oscillations, prediction error, and hierarchical integration in speech production. This framework also explains the contextual variability of stuttering behaviors, including adaptation effects and fluency-inducing conditions. Reframing stuttering as a synaptopathy integrates neurobiological, psychological, and behavioral dimensions, suggesting disruptions in precision-weighting mediated by neuromodulatory systems. This active inference perspective provides a unified account of stuttering and sets the stage for innovative research and therapeutic approaches.The author(s) declare that no financial support was received for the research and/or publication of this article
Characterizing Hey2 as a Six1-Interacting Protein
No full textenterBranchio-oto-renal spectrum disorders (BORSD) are a type of congenital
hearing loss disorders found in roughly 2% of profoundly deaf children. BORSD not
only affects ear development, but also has the potential to cause other developmental
defects such as branchial fistulae and cysts in the neck, as well as renal abnormalities.
So far, mutations in two genes, SIX1 and EYA1, have been found to be the primary
contributors to BORSD, but these still only account for 44% of those who suffer from
this disorder. In recent years, researchers have worked to identify other genes
involved in the SIX1 developmental pathway, particularly cofactors that may
modulate the activity of SIX1 and EYA1 and could contribute to the wide variability
of symptoms observed in BORSD patients. HEY2 is one of these potential cofactors
that has been identified using a yeast 2-hybrid screen, but further studies are required
to determine if it truly has a role as a SIX1 cofactor. Using Xenopus laevis as a model
organism, we conducted in situ hybridization on embryos to discover that hey2 is
partially coexpressed with six1 during larval stages of development, pointing to a
possible interaction in vivo. Additionally, luciferase assays have shown that Hey2
increases Six1 transcriptional activity in vitro, potentially by strengthening the Six1-
Eya1 interaction. Further research is needed to determine if this increase in activity is
due to direct binding of Hey2 and Six1, but our early findings show that Hey2 is a
promising Six1 cofactor that may contribute to BORSD.ente
Increased apoptosis and decreased volume in the nucleus reuniens of the midline thalamus following alcohol exposure in a third trimester model of FASDs
No full textKlintsova, Anna Y.Fetal alcohol spectrum disorders (FASDs) is a term used to encompass an array of disorders that result from the consumption of alcohol during pregnancy. Approximately 2-5% of live births in the United States are diagnosed with FASDs, despite being entirely preventable. FASDs range in symptoms, which range from facial abnormalities to cognitive deficits. While facial abnormalities do not usually extend past early trimester exposure, cognitive deficits, such as deficits in executive functioning (EF), can still occur following a third trimester alcohol exposure. EF relies on the communication between the hippocampus (HPC) and medial prefrontal cortex (mPFC) through circuitry involving the midline thalamic nucleus reuniens (Re), suggesting that deficits seen in FASDs are due in part to damage of Re. ☐ The current study used a rodent model of third trimester FASDs to examine the damage to Re following a single day alcohol exposure on postnatal day (PD) 9. Re damage was characterized in this study by the estimation of apoptotic cell number 12 hours after alcohol exposure, estimation of total cell number in adulthood, estimation of neuron and astrocyte numbers in adulthood, and estimation of volume of the region. Long Evans rats were either administered a high dose of alcohol (5.25 g/kg/day; AEhigh), moderate dose of alcohol (3.0 g/kg/day; AEmod), or were sham intubated (SI) on PD9. Rats were sacrificed either 12 hours after exposure on PD9, or on PD65. Brain sections were stained with cresyl violet or fluorescent anti-NeuN (against neurons) and anti-GFAP (against astrocytes). Cresyl violet was used to visualize and estimate total cell number (PD65) and to visualize and estimate the number of apoptotic cells (PD9) in Re. Fluorescent anti-NeuN and anti-GFAP were used to visualize and quantify mature neurons and astrocytes, respectively, in Re on PD65. ☐ The number of apoptotic cells in Re on PD9 12 hours after alcohol exposure was significantly different across postnatal treatments, such that pups in the AEhigh treatment had significantly more apoptotic cells in Re when compared to SI pups and pups in the AEmod treatment. A main effect of sex was also seen, as females showed significantly greater levels of apoptosis in Re than males. Postnatal treatment also significantly affected the volume of Re on PD9 12 hours after exposure, such that pups in the AEmod treatment had a significantly lower volume of Re when compared to SI pups and pups in the AEhigh treatment. No significant effects of alcohol exposure were seen on total cell number, neuron number, astrocyte number, or volume on PD65. These results indicate that the Re is directly damaged following alcohol exposure exemplified by higher levels of cell death and decreased volume when compared to controls, but differences in cell number and volume between conditions were not observed in adulthood, suggesting that the damage to Re directly following AE is not sustained.University of Delaware, Department of Psychological and Brain SciencesM.S
Characterization of spe-43 homologs: K05F1.1 and F57A8.6
No full textKrauchunas, AmberSexual reproduction relies on the presence of a viable sperm cell, which fuses with an egg cell in the process of fertilization. To increase understanding of the molecular processes involved in sexual reproduction, a reverse genetics method can be utilized to learn the role of specific proteins in fertility. C. elegans are an excellent organism to model these processes with, as they reproduce through sexual reproduction. C. elegans exhibits two sexes: hermaphrodites, which can self-fertilize, as well as males, which produce sperm to fertilize eggs from the hermaphrodites. Sperm activation is the process through which post-meiotic spermatids are altered to become sperm suitable for fertilization. In C. elegans, the process is triggered through two different pathways: TRY-5 and SPE-8. The TRY-5 pathway and the SPE-8 pathway are active in the male reproductive tract, while only the SPE-8 pathway is active in hermaphrodites. Hermaphrodites with mutations in genes required for the SPE-8 pathway experience self-sterility. In contrast, males with non-functional TRY-5 pathway components show no fertility defect unless the SPE-8 pathway is also disabled. spe-43 is a protein-encoding gene required for sperm activation through the SPE-8 pathway. spe-43 has three different paralogs: K05F1.1, F57A8.6, and T10E9.4. All three paralogs are protein-encoding genes hypothesized to be involved in sperm activation. To study the role of K05F1.1 and F57A8.6 in C. elegans fertility, deletion mutants were made to knock out the genes’ function. Quantitative experiments, including hermaphrodite self-fertility assays and male fertility assays, display no significant difference in progeny produced by K05F1.1(syb4161) deletion mutants compared to wild type organisms. Similarly, imaging such as DAPI staining and sperm dissections have shown that loss of K05F1.1 has no visible impact on sperm production, localization, and sperm morphology. When knocking out K05F1.1 and spe-8 together, males were able to produce viable progeny. The result implies that the K05F1.1 protein is neither part of the TRY-5 pathway, nor the SPE-8 pathway. In contrast, F57A8.6(syb4189) deletion mutants had significantly fewer progeny produced compared to wild type organisms in quantitative experiments.Senior Thesis Progra
Body composition in patients with obesity‐related heartfailure with preserved ejection fraction: A comparison study
No full textThis is an open access article under the terms of the Creative Commons Attribution‐Non Commercial License (https://creativecommons.org/licenses/by-nc/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.© 2025 The Author(s). Journal of Parenteral and Enteral Nutrition published by Wiley Periodicals LLC on behalf of American Society for Parenteral and Enteral Nutrition.Hannah Salmons and Syed Imran Ahmed contributed equally to this work.
This article was originally published in Journal of Parenteral and Enteral Nutrition. The version of record is available at: https://doi.org/10.1002/jpen.70013Background: Appendicular lean mass index is a major determinant of cardiorespi-ratory fitness in patients with obesity‐related heart failure with preserved ejectionfraction (HFpEF). Moreover, appendicular lean mass index can be used to diagnosesarcopenia and sarcopenic obesity in this population. We aimed to validate theability of segmental single‐frequency bioelectrical impedance analysis (SF‐BIA) toassess body composition compared with dual‐energy x‐ray absorptiometry (DXA) inpatients with HFpEF and obesity, with a focus on appendicular lean mass index forits critical role in diagnosing sarcopenia and sarcopenic obesity.This study was partially supported by a Career Development Award 19CDA34660318 from the American Heart Association to Salvatore Carbon
Machine learning for pediatric healthcare
No full textBeheshti, RahmatollahRecent ML advances have shown significant promise in assisting clinical decision-making in healthcare. In particular, the integration of ML predictive models into clinical settings has the potential to transform patient care through more personalized, timely, and effective interventions. Despite extensive research on ML for health in adults, there is a research gap regarding its application within pediatric populations. Children are not just "small adults"; they differ from adults in many ways that could affect the performance of ML models. These differences underscore the importance of tailoring ML approaches to pediatric care. ☐ In this work, we focus on two major pediatric health issues—obesity and sleep apnea—and explore ML applications in these domains. First, we propose a multi-task deep learning model that predicts BMI trajectory and attrition patterns among weight management program participants using EHR data. Second, we target sleep apnea detection using polysomnography (PSG) signals in children. We present a transformer-based architecture to detect apnea using multimodal biosignals. Subsequently, we investigate the contribution of each signal for apnea detection and identify a subset of signals that achieves a performance comparable to the complete set. We also study the effect of missing and noisy signals (a phenomenon commonly observed in pediatric settings) in apnea detection and present a tailored ML architecture and training algorithm that yields a robust apnea detector model. ☐ In this talk, we additionally cover two recent projects in more detail. The first one relates to extending the obesity case study above, where we develop an end-to-end pipeline following FHIR (Fast Healthcare Interoperability Resources) standards to predict patients' risk of obesity at different future ages. We also use a rigorous uncertainty quantification method to measure the uncertainty of our prediction. Our ML pipeline targets maximizing interoperability across various EHR formats and designing a user (provider)-centric UI to enable effective integration of our tools into clinical practice. ☐ Recognizing the growing influence of LLMs in healthcare, in the second project, we aim to address the need for scalable evaluation of fairness in LLMs. We propose a greatly customized RAG-based pipeline to generate synthetic red-teaming patient scenarios (vignettes) to evaluate social biases in medical LLMs. We merge an auxiliary generator LLM with medical knowledge graphs and a post hoc fact checker module in our design to minimize hallucination patterns when using an LLM-based pipeline and to follow an evidence-based scenario generation approach.University of Delaware, Department of Computer and Information SciencesPh.D