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Evolving Your Relationship with AI by the Creative AI Academy
No full textThis session will bridge the gap between AI curiosity and AI utility. We will deep dive into the practical aspects of AI, demonstrating methods for educational innovation, strategic research, and the AI communication techniques that elevate outcomes and improve workflows. Please bring your laptop as this will be a hands-on session
Proximal Carceral Contact: The Relationship Between Parental Incarceration and Children’s Political Participation
No full textM.P.P.The United States has the highest prison population rate in the world, and approximately half of all people incarcerated in the United States are parents to children under 18 years old. As a result, more than five million children, or one in fourteen, have experienced parental incarceration at some point in their lifetime. Incarceration not only has impacts on the individuals incarcerated but also on their close contacts, friends, and family members. Existing studies indicate that having been incarcerated is negatively associated with political participation. Some research has begun to look at the impact of having proximal carceral contact with someone involved in the criminal legal system on one’s own political participation, but very little has focused specifically on the impact of parental incarceration on the political participation of their children. Using data from the National Longitudinal Survey of Youth 1997, my results suggest that parental incarceration has a negative relationship with children’s interest in following government and public affairs as well as their likelihood of voting, but is unrelated to children’s likelihood of attending public meetings and making public monetary donations
Methylation Patterns of Cell-Free DNA in the Circulation Reveal Tissue-Specific Cellular Damage
No full textPh.D.DNA methylation is an epigenetic regulatory mechanism that dictates chromatin organization and transcriptional programs to establish the landscape of cellular identity. This work centers on revealing fundamentals of cell-type-specific DNA methylation through generation of atlases using methylation-sequencing data from 40 purified cell-types in 30 distinct healthy tissues, for mouse and human species. Unsupervised clustering analysis reveals that developmental lineage primarily drives the relationship between methylomes. Surprisingly, methylation patterns are highly conserved amongst replicates of the same cell-type, despite heterogeneity of sample sources representing over 350 individuals. Cell-type-specific DNA blocks were mostly hypomethylated and located at intragenic enhancer regions, coinciding with other cell-type-specific epigenetic marks. Further, binding sites for pioneer transcription factors were enriched demonstrating that methylation blocks in the atlases reflect programmed changes established during development that are stably maintained in terminally differentiated cell-types. The atlases serve as a valuable resource for many applications, including translational use to indicate tissue turnover from cell-free DNA (cfDNA) in blood samples. Liquid biopsies are emerging as a minimally-invasive, complementary approach to traditional tissue biopsies. DNA methylation can be used to trace the tissue and cellular origins of cfDNA fragments released into the circulation from dying cells. Changes in cfDNA can be due to physiologic or disease-driven tissue remodeling or induced by tissue damages from different treatments. We established a protocol whereby cfDNA fragments were captured from serum samples by hybridization to CpG-rich DNA panels and mapped to the DNA methylation atlases to derive their tissue origin. The first chapter uses this approach to reveal tissue-specific, cellular damage from radiation treatment, using serial samples collected before and after therapy in breast cancer patients and also using a mouse model. The second chapter uses the same approach to monitor cellular damages post-liver transplant impacting the graft tissue as well as host organs to identify causes of graft injury.
In sum, this dissertation describes a comprehensive approach that can reveal the cellular level of tissue damages from a wide-range of interventions detectable from blood samples
Impact of an Open Access Scheduling System on No-Show Rates in an Urban Federally Qualified Health Center
No full textD.N.P.No-show medical appointments lead to health disparities and threaten the financial survival of Federally Qualified Health Centers (FQHCs). Open access scheduling eliminates long lead times, a common reason for no-show visits. Preventive health screenings and chronic disease management were drastically reduced during the COVID-19 pandemic, requiring innovative methods to increase access to care. The purpose of this quality improvement (QI) project was to measure the impact of an open access scheduling system on no-show rates in an urban FQHC. A pre-post observational design compared two days per week of no-show data for a span of 10 weeks between two family medicine physicians’ schedules. No-show data from the pre-intervention group (N = 175) was collected from October 17, 2022–December 20, 2022 and compared to no-show data from the open access post-intervention group (N = 82) collected from October 16, 2023–December 19, 2023. No-show rates were significantly lower in the open access post-intervention group (3.5%) compared to the traditional pre-intervention group (36%),
Examining the Equity of FEMA’s Individuals and Households Program
No full textM.P.P.Disasters often have a disproportionately negative impact on vulnerable social and economic communities, which can lead to slower recovery times relative to more affluent populations. Historically, disaster assistance distributed by the Federal Emergency Management Agency (FEMA) has maintained or exacerbated these gaps. In September 2021, FEMA published an amendment to the Individual Assistance Program and Policy Guide 1.1, which introduced policy changes to FEMA’s Individuals and Households Program (IHP) intended to make post-disaster assistance more accessible to historically underserved populations. This paper analyzes applicant-level FEMA data and demographic data from the U.S. Census Bureau to determine whether eligibility rates increased for a greater proportion of low-income and Black Americans following the 2021 policy changes. My analysis finds mixed results: Post-policy change eligibility rates for applicants from counties with higher percentages of Black residents did increase relative to applicants from counties with higher percentages of White residents, but eligibility rates for low-income applicants did not increase relative to higher income applicants. This research has important implications for the efficacy of using policy design to achieve equity outcomes, and is especially timely as FEMA continues to implement new policy changes to the IHP that are further intended to advance the Agency’s equity goals
Intratumor Heterogeneity Drives the Evolution of Multiple Populations with Metastatic Initiating Capabilities in a Genetically Engineered Mouse Model of Triple Negative Breast Cancer
No full textPh.D.Heterogeneity within primary tumors allows cancer cells to acquire traits advantageous to their survival and growth, but a better understanding of how this heterogeneity influences metastasis is required. Using a genetically engineered mouse model (GEMM) of triple negative breast cancer (TNBC), we investigated the evolution of tumor heterogeneity during disease progression, and its contribution on metastasis. Here, we show that late malignant tumors (LM) have an enhanced ability to invade and form pulmonary metastases compared to early malignant (EM) tumors. To understand the changes taking place during progression to promote this enhanced metastatic capability, we employed bulk RNA-sequencing (RNA seq) and single cell RNA-sequencing (scRNA-seq). RNA-seq revealed that LM tumors are enriched in programs that contribute to invasion and metastasis such as epithelial-mesenchymal-transition (EMT), hypoxia, and ECM-receptor interactions. Even though the contribution of EMT on metastasis is unclear, the significant upregulation of EMT genes in LM tumors led us to assess experimental lung metastases for two canonical EMT markers, EpCAM and Vimentin. We found that lung metastases formed from LM tumors expressed varying levels of Vimentin, which did not always mirror the EMT phenotype of the primary tumor. scRNA-seq revealed the transcriptional heterogeneity that exists between and within LM and EM tumors, showing subpopulations with unique molecular signatures. During tumor progression, LM tumors experience a loss of mammary epithelial lineage as observed by the downregulation in luminal genes such as Krt8, Wfdc18, Ptn, Kit, Barx2, and Prom1. However, LM tumors did not exhibit a gain in basal features (Trp63, Col17a1, and Krt14). To better understand the contribution of tumor heterogeneity on metastasis, we identified three subpopulations that were unique to LM tumors including EpCAM low, EpCAM high Itga2 low, and EpCAM high Itga2 high tumor cells. While EpCAM low subpopulations exhibited an enhanced ability to invade in vitro, EpCAM high subpopulations displayed a greater ability to form lung metastases. Importantly, we found that multiple subpopulations are comprised of metastasis-initiating cells (MICs), and this metastatic capability was independent of their EMT status. Additionally, our findings suggest that mesenchymal-epithelial-transition (MET) is not required for tumor cells to survive and proliferate after the colonization of a secondary site. Collectively, our findings reveal the existence of MICs in multiple tumor subpopulations, and provides insight to the contribution of heterogeneity and EMT on metastasis
The Skin of Sensation: Permeability, Corporeality, and Subjectivity in Victorian Sensation Fiction
No full textM.A.Though often experienced as a static, unchanging organ, skin in the Victorian era was rife with both medical and symbolic meaning. Depictions and descriptions of skin within Victorian sensation fiction provide an avenue for understanding the inner mechanisms of the novels as they present characters in relation to one another as each perceives the other and are perceived in return. By examining skin within the sensation novels Lady Audley’s Secret by M. E. Braddon, East Lynne by Mrs. Henry Wood, and The Moonstone: A Romance and Poor Miss Finch: A Domestic Story by Wilkie Collins, this study shows how the novels depict the processes of gendering and racialization through skin, show the prejudices and beliefs of their characters, and infuse a sense of queerness into narratives often framed as conservative and serving a normative social function. As characters within the novels interpret each other and present themselves through skin, the narratives reveal how skin becomes a mediator between ‘surface’ and ‘depth,’ allowing for an interplay between expectation based on factors such as gender, race, ability, etc. and self-construction. Through this mediation, characters are made visible and readable to each other, allowing the novels to abide by or subvert wide societal ideologies and narrative conventions of sensation fiction and the novels of the mid-Victorian era at large
Identity Ruptures & Community Fragmentation: Afghans Resettling in the U.S. after the Taliban Takeover
No full textAn Investigation of the Neural Dynamics Underlying Speech Perception and Production: EEG Evidence for Internal Inverse and Forward Models
No full textPh.D.Dual stream models of language processing provide a functional neuroanatomical model for auditory speech processing, however, the neural dynamics underlying speech processing as well as the sensorimotor transformations in these pathways are still poorly understood. Internal models predict the interaction between sensory and articulatory representations: forward internal models predict sensory outcomes of speech production, linking motor areas to perceptual areas; inverse internal models, on the other hand, link speech outcomes to motor plans by bridging sensory to articulatory representations during speech perception. In this study, I used electroencephalography (EEG), carefully designed behavioral stimuli, and multivariate analysis techniques to systematically investigate the nature of neural representations and their predicted dynamic interactions during speech perception and production. First, I validated the approach by replicating prior electrocorticography (ECoG) findings regarding the latency and organization of speech information during perception. I then found that the sensorimotor transformation between different neural representations during speech perception and production corresponded to the hypothesized internal model framework. Specifically, I found evidence for an inverse model from perceptual representations in temporal channels to articulatory representations in superior frontal channels during speech perception, and for a predictive forward model from frontal to temporal channels active during speech production. Intriguingly, this forward model appeared to include the anteroventral stream. In addition, I found evidence that the organization of speech representations in different parts of the brain’s speech network is task-dependent and dynamic