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Internal structure and chemical composition of arthropods from Early Miocene Dominican Republic amber
No full textSubmission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-08-01The student, Cariad Williams, accepted the attached license on 2025-07-17 at 13:27.The student, Cariad Williams, submitted this Thesis for approval on 2025-07-18 at 11:34.This Thesis was approved for publication on 2025-07-21 at 14:58.DSpace SAF Submission Ingestion Package generated from Vireo submission #22640 on 2025-10-21 at 10:06:11Amber is a remarkable mode of fossil preservation, often capturing fine anatomical details such as coloration, three-dimensional morphology, internal structures, and even ecological interactions. This fidelity enables reconstructions of ancient ecosystems and evolutionary pathways. Among global deposits, Early Miocene amber from the Dominican Republic (DRA) is considered among the most exceptional in quality. In the introductory chapter of this thesis, I review the current state of knowledge on the taphonomic pathways involved in the preservation of insects in amber. In Chapter Two, I apply complementary microscopy (light and electron) and elemental analysis (energy dispersive X-ray analysis) to investigate the internal structures of five arthropods preserved in DRA—two Coleoptera and three Hymenoptera, including two Formicidae. Mummified internal tissues were preserved in several specimens, including sclerotized tubes identified as tracheae, an organ interpreted as the crop, and Malpighian tubules. Elemental analysis of the preserved arthropods revealed consistently high levels of carbon and oxygen, indicating organic preservation. Surprisingly, silica and phosphorus were also detected—anomalous for amber fossils, which typically preserve through resin polymerization rather than mineral replacement. This suggests some degree of permineralization occurred within the amber matrix. These findings underscore the exceptional preservation potential of DRA and its value for reconstructing arthropod physiology and Miocene biodiversity. Further analysis of additional elements (e.g., aluminum, calcium, potassium) is warranted. Future work should include gas chromatography–mass spectrometry (GC-MS) of extant Hymenaea resin to assess the compositional relationship between modern and fossilized resin. Microscopy and elemental analysis of amber inclusions provide critical tools for paleoentomology, advancing understanding of fossilization pathways, organismal biology, and ancient environments
Syntactic adaptation and word learning across contexts and development
No full textSubmission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-08-01The student, Yukun Yu, accepted the attached license on 2025-07-04 at 14:12.The student, Yukun Yu, submitted this Dissertation for approval on 2025-07-04 at 14:20.This Dissertation was approved for publication on 2025-07-08 at 12:54.DSpace SAF Submission Ingestion Package generated from Vireo submission #22411 on 2025-10-25 at 15:30:49Children acquire language in the face of pervasive ambiguity, relying not only on innate biases but also on their ability to learn from linguistic experience. This dissertation examines syntactic adaptation as a mechanism through which children revise their expectations about the syntactic behavior of familiar words based on recent experience and use these updated expectations to support novel word learning. Building on research in syntactic bootstrapping and structural priming, I investigate whether syntactic adaptation reflects a form of long-term, implicit, error-driven learning that emerges early in development and generalizes beyond specific contexts. Across four preferential-looking experiments, children from three age groups (3-year-olds, 24-month-olds, 18-month-olds) received induction exposure in which a familiar ambiguous phrase, the baby, was consistently followed by either nouns (e.g., “the baby elephants”) or verbs (e.g., “the baby draws”). In subsequent test trials, children heard novel words following this phrase (e.g., “the baby gorps”). Findings revealed significant adaptation effects across all age groups: Children who received the verb induction exposure were more likely to interpret the novel words as verbs compared to those who received the noun induction exposure. These effects persisted over a one-day delay (Experiment 1), generalized in the absence of visual referential overlap (Experiment 2), and were observed even in 24- and 18-month-olds (Experiments 3 and 4). Among 3-year-olds, adaptation was stronger when the induction structure was less common in child-directed speech, suggesting a surprisal effect consistent with error-based learning accounts. In 24-month-olds, adaptation effects also varied by induction condition, but in a reversed way, raising questions about potential developmental differences in how children track and adapt to syntactic patterns. Possible explanations for these differences are discussed, along with broader developmental trends across the three age groups. Together, the findings demonstrate that children use recent input to update syntactic predictions about familiar content words and use these expectations to support word learning. This work advances our understanding of syntactic adaptation as a powerful mechanism in language development
Exploring trauma and trauma-informed care with Black special educators and general educators: a qualitative study
No full textSubmission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-08-01The student, Alexandra Richmond, accepted the attached license on 2025-07-16 at 13:39.The student, Alexandra Richmond, submitted this Dissertation for approval on 2025-07-16 at 13:46.This Dissertation was approved for publication on 2025-07-17 at 11:48.DSpace SAF Submission Ingestion Package generated from Vireo submission #22603 on 2025-10-25 at 15:31:02The empirical research for trauma-informed care in schools is growing, yet there continues to be little to no research conducted on how trauma and trauma-informed care may differ based on racial and cultural differences. The purpose of this study was to explore how Black educators understand trauma and experience trauma-informed practices in their classrooms. Across four focus groups, 28 Black educators discussed their understanding of trauma and trauma-informed care, current trauma-informed practices, and the supports that they have and need to successfully implement trauma-informed care. To achieve a deeper understanding, general educators and special educators were initially analyzed separately through a critical lens, and then a comparative analysis was conducted to examine similarities and differences across both groups. The implications for research, practice, and policy are discussed
Finishing school: analysis of the “Complete to Compete” completion grant program at Elgin Community College
No full textSubmission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-08-01The student, David Davin, accepted the attached license on 2025-07-16 at 18:55.The student, David Davin, submitted this Dissertation for approval on 2025-07-16 at 19:01.This Dissertation was approved for publication on 2025-07-17 at 16:41.DSpace SAF Submission Ingestion Package generated from Vireo submission #22619 on 2025-10-25 at 15:31:03This dissertation investigates the Complete to Compete (C2C) completion grant program at Elgin Community College (ECC), specifically targeting community college students facing financial barriers to graduation. Utilizing simple data analysis and a qualitative approach, the study analyzes institutional graduation data, survey responses, and student interviews to examine how direct financial support influenced student persistence and degree completion. Results from the institutional data indicate that the C2C program was associated with higher graduation outcomes, with 82.5% of participating students completing their degrees compared to the institution’s historical average of 47.5%. Survey and qualitative findings revealed that the C2C program provided critical financial relief, reduced students' stress, enhanced academic engagement, increased institutional validation, and encouraged future-oriented planning. These holistic supports contributed substantially to the students’ improved academic outcomes. The research also critically examines the broader equity implications of such programs within higher education frameworks. Applying the concept of Whiteness as property (Harris, 1993), the study highlights how traditional institutional structures disproportionately disadvantage racially and socioeconomically marginalized students. In doing so, this dissertation argues for reimagining higher education equity through a "queering" lens—questioning conventional norms and advocating for systemic change in policy and practice
Statistical inference in complex networks: community detection, change-point detection, link prediction, and two-sample testing
No full textSubmission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-08-01The student, ByeongJip Kim, accepted the attached license on 2025-06-27 at 12:20.The student, ByeongJip Kim, submitted this Dissertation for approval on 2025-06-27 at 12:40.This Dissertation was approved for publication on 2025-06-30 at 13:32.DSpace SAF Submission Ingestion Package generated from Vireo submission #22376 on 2025-10-25 at 15:52:51Network data are non-Euclidean relational data that consist of vertices (nodes) and edges (links). Such relational data are ubiquitous in everyday life, appearing in systems like public transportation networks, social relationships on platforms such as social networking services, and user-generated reviews on websites like Yelp. Beyond these familiar examples, networks also span a wide range of domains\textemdash from macroscopic systems like the World Wide Web to microscopic ones like gene interactions. In the era of the Fourth Industrial Revolution and big data, the statistical analysis on network data has the power to intellectually inspire other related disciplines, as well as the statistical society. The cutting-edge data storage and acquisition in this era enable us to access massive network datasets from various academic domains. Given the wide variety of networks in the world, diverse theories and methods are required to study their unique characteristics. For example, networks can exhibit different types of nodes, e.g., both human nodes and product nodes in review networks like Yelp. In addition to heterogeneous node types, we often observe different link types frequently; for example, yeast networks can exhibit multiple link (interaction) types among genes. Networks can also evolve over time. For instance, online dynamic networks involve streaming datasets where graph snapshots arrive sequentially in real time, while offline dynamic networks capture historical data through a series of graph snapshots that are fully available at the time of analysis. The vast and varied landscape of network types, combined with the growing availability of complex network data, requires the development of novel theories and methodologies tailored to each context. However, traditional methods and theories are often not directly applicable to these new network data or leave spaces for significant improvement. This dissertation aims to extend existing theories and methods to more complex networks. Moreover, this dissertation develops new theories and methods for key statistical challenges in dynamic networks, including discovering the latent network structure (communities), detecting the structural changes (change points in dynamic networks), predicting the future networks when there is no change point in dynamic networks, and comparing different networks. The first three problems focus on a single network, which may be a uni-layer, multi-layer, or dynamic network. In contrast, the fourth problem focuses on the joint analysis of two multi-layer networks
Elucidation of genetic targets and high throughput phenotyping methods for improvements to crop sustainability
No full textSubmission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-08-01The student, Robert Twohey III, accepted the attached license on 2025-06-29 at 20:02.The student, Robert Twohey III, submitted this Dissertation for approval on 2025-06-29 at 20:17.This Dissertation was approved for publication on 2025-07-16 at 09:37.DSpace SAF Submission Ingestion Package generated from Vireo submission #22382 on 2025-10-25 at 15:52:53As climate change causes sporadic rainfall patterns and increased drought, there is a greater need to develop new Zea mays lines with improved water use efficiency. Identifying genetic targets and improving our understanding of the mechanisms driving variation within individual traits will provide the opportunity to breed crops for increased water use efficiency. This dissertation investigates a subset of component traits related to water use efficiency and aims to improve our understanding of the variation present within traits related to water use efficiency and use quantitative genetic approaches as an attempt to identify genetic targets that will allow for the future development of climate resilient crops. First, a Z. mays line with a highly negative carbon isotope signature was used to develop a biparental mapping population to identify a single large effect QTL. Further investigation revealed a large deletion in the carbonic anhydrase 1 gene. This mutation led to a decoupling of carbon isotope signature and intrinsic water use efficiency suggesting a better understanding of this relationship is necessary before carbon isotope signatures can be used as a proxy measurement of intrinsic water use efficiency in C4 species. Next, a slac1-2 mutant hybrid with stomata that were always open was grown across multiple field environments for physiological and agronomic characterization. The relationship between stomatal conductance, photosynthesis, and yield was dissected and provides evidence to support an opportunity to improve intrinsic water use efficiency with further reductions in stomatal conductance while maintaining photosynthetic productivity. Wild-type Z. mays hybrids did not show any photosynthetic or yield reduction due to decreased stomatal conductance when compared to the slac1-2 open stomata phenotype hybrid. Next, a new high throughput phenotyping protocol measuring limited transpiration response to increasing vapor pressure deficit was developed and tested. Significant variation was observed in stomatal response and vapor pressure deficit sensitivity traits when gas exchange was collected from the Nested Association Mapping Founders under high vapor pressure deficit. Chamber and field measurements of transpiration response under increased vapor pressure deficit were compared and while vapor pressure deficit breakpoints were seen in both environments, differences were observed in the rate of stomatal response and vapor pressure deficit sensitivity. Finally, a large QTL associated with specific leaf area was identified in two Nested Association Mapping Recombinant Inbred Line populations. Further investigation of the QTL interval was unsuccessful in identifying a refined interval or candidate genes; however, this work provides a new genomic target for future studies. These objectives describe the use of genetic variation within several water use efficiency component traits combined with leveraging new screening protocols and genetic tools to improve our understanding of the mechanisms controlling water use efficiency in Z. mays. The findings described in this dissertation can act as a foundation for future studies leading to lines with improved sustainability traits
Development of spatial and single-cell omics methods for biochemical profiling of the brain
No full textSubmission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-08-01The student, Marisa Asadian, accepted the attached license on 2025-07-08 at 21:47.The student, Marisa Asadian, submitted this Dissertation for approval on 2025-07-08 at 22:34.This Dissertation was approved for publication on 2025-07-14 at 11:30.DSpace SAF Submission Ingestion Package generated from Vireo submission #22436 on 2025-10-25 at 15:53:16Understanding the molecular basis of brain function and dysfunction requires analytical tools with both spatial precision and cell-type specificity, along with the ability to profile the diverse chemical composition underlying cellular heterogeneity. The brain is composed of diverse cell types, with molecular identities shaped by spatial context, dynamic metabolic states, and complex intercellular signaling. To dissect these layers of complexity, this dissertation presents the development and application of spatial and single-cell omics approaches for multiscale biochemical profiling of the brain across species and disease. In the first study (Chapter 2), expansion microscopy was integrated with multiplexed error-robust fluorescence in situ hybridization (MERFISH) to characterize the spatial transcriptome of the honeybee (Apis mellifera) brain. This approach enabled the mapping of aggression-associated genes linked to social behavior in this eusocial insect. The combined technique also demonstrated the feasibility of detecting and decoding mRNA fluorescence spots in the densely packed honeybee brain, which contains approximately one million neurons in a 1 mm³ volume, highlighting its ability to map molecular activity in small, compact brains. Importantly, this study establishes a framework for investigating the spatial molecular basis of social behavior using the honeybee as a model organism. The second study focuses on lipidomics, a key omics field given that lipids account for over 50% of the brain’s dry weight and play vital roles in maintaining homeostasis and cellular signaling. Presented in Chapter 3, a high-throughput sequential single-cell workflow was developed by leveraging the untargeted capability of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to obtain lipid signatures across thousands of cells. This was combined with multiplex antibody labeling using photocleavable mass-tags for cell classification. Applied to isolated hippocampal cells from the rodent brain, this approach demonstrated the feasibility of performing cell-type- and cell-state-specific lipidomic analyses in this functionally complex brain region, revealing lipid enrichments specific to both cell type and neuronal cell state. Finally, Chapter 4 presents a multimodal spatial lipidomic workflow that combines salt doping with MALDI-2 post-ionization for enhanced detection of neutral lipid remodeling associated with Alzheimer’s disease (AD) in postmortem human brain tissue. This method, combined with post–MS imaging immunohistochemistry (MSI-IHC) of amyloid-beta plaques and phosphorylated tau in neurofibrillary tangles, enabled the detection of lipids colocalized with AD pathology. Additionally, a correlation analysis of lipid changes in human AD tissue compared with the 5xFAD mouse model is presented, supporting the translational relevance of the mouse model for future AD studies. Together, this dissertation presents omics approaches that advance our understanding of spatial molecular activity in the brain, as well as subcellular biochemical diversity that contributes to cell heterogeneity, brain function, and disease processes
Endometrial extracellular vesicles during pregnancy: their regulation by transcription factor RUNX1 and dysregulation by phthalate exposure
No full textSubmission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-08-01The student, Jacob Beal, accepted the attached license on 2025-07-16 at 14:47.The student, Jacob Beal, submitted this Dissertation for approval on 2025-07-16 at 14:54.This Dissertation was approved for publication on 2025-07-17 at 16:33.DSpace SAF Submission Ingestion Package generated from Vireo submission #22587 on 2025-10-25 at 15:54:09During early pregnancy, endometrial stromal cells in the maternal uterus play a crucial role in coordinating significant events necessary for reproductive success by secreting paracrine factors, including extracellular vesicles (EVs) that contain diverse molecular cargo, facilitating critical processes such as embryo implantation, uterine neoangiogenesis, and trophoblast differentiation. The secretion of EVs from endometrial stromal cells is regulated by a conserved pathway involving hypoxia-inducible factor HIF2α, which controls the expression of RAB27B, a vesicular trafficking protein necessary for the release of EVs into the extracellular space. In human endometrial stromal cells (HESCs), runt-related transcription factor RUNX1 has been identified to act upstream of HIF2α to facilitate proper EV secretion and the inclusion of specific protein cargoes, including insulin-like growth factor IGF2. Consequently, EVs collected from HESCs with reduced RUNX1 or IGF2 expression were less effective in promoting angiogenesis or trophoblast differentiation. In a conditional knockout mouse model in which the gene encoding IGF2 was ablated in the maternal uterus, we observed a reduction in litter size and smaller offspring, attributed to defective placental development. Understanding the regulation of the EV signaling pathway and how it can be disrupted is critical, as impairment of cell-to-cell communication within the uterus during early pregnancy can significantly affect placental development and fetal growth. Our study demonstrated that exposure to an environmentally relevant concentration of phthalates, well-known endocrine disruptors, disrupts the EV secretion pathway in HESC by inducing abnormal DNA methylation, which impairs the estrogenic promotion of HIF2α expression. Collectively, these findings highlight the essential role of the RUNX1-HIF2α-RAB27B pathway in mediating the regulation of EV secretion from endometrial stromal cells, emphasizing that disruptions caused by environmental insults or diminished expression of upstream factors or essential protein cargoes can impair EV secretion and hinder key processes vital for placental development and reproductive success
“Value-laden”: exploring constructivist values in the design and implementation of digital inquiry modules for middle school science classrooms
No full textSubmission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-08-01The student, McKenna Lane, accepted the attached license on 2025-07-16 at 15:50.The student, McKenna Lane, submitted this Dissertation for approval on 2025-07-16 at 16:12.This Dissertation was approved for publication on 2025-07-18 at 05:51.DSpace SAF Submission Ingestion Package generated from Vireo submission #22611 on 2025-10-25 at 15:54:15Science education reforms in the United States emphasize student-centered inquiry and engagement with authentic disciplinary practices. Guided by the Next Generation Science Standards (NGSS), these reforms are grounded in constructivist theories of learning that position students as active meaning makers. However, little is known about how constructivist values are interpreted and enacted during the design of digital inquiry modules, or the impact of these values on the experience of students and teachers who use them. In this study, I describe the design and implementation of a digital inquiry module created by an interdisciplinary, museum-based design team for use by students and teachers in middle school science classrooms, focusing on how constructivist theories of teaching and learning are embedded in the design process and experienced by teachers and students who use the module. To do this, I conducted a sequential mixed methods study that uses Reflexive Thematic Analysis (Braun & Clarke, 2022) and descriptive statistics to explore the perspectives of the a) module designers and the b) teachers who used a related digital inquiry module in their classrooms, and c) “students” as described by their teachers. The study is guided by the following questions: 1) To what extent are constructivist values toward teaching and learning applied to the collaborative design of an NGSS-aligned digital inquiry module created by an interdisciplinary design team for use in science classrooms? 2) How are constructivist values experienced by teachers who use the digital inquiry module in their science classes? 3) What are teachers’ perspectives of their students’ experiences with the digital inquiry module? My findings describe how the design team and teachers valued authenticity and accuracy of module materials and activities, matching the design to students’ abilities, supporting student engagement, providing meaningful learning experiences, and connecting to the broader classroom context, albeit with slightly different emphases for these themes. I discuss the similarities and differences between these perspectives and end with implications for museums, design teams, and educators
Impact of communication competence on acceptance, performance perception, and career development: a mixed methods study of the experiences of non-native English-speaking employees in corporate America
No full textSubmission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2027-08-01The student, Adetutu Fabusoro, accepted the attached license on 2025-07-18 at 09:12.The student, Adetutu Fabusoro, submitted this Dissertation for approval on 2025-07-18 at 10:08.This Dissertation was approved for publication on 2025-07-18 at 11:48.DSpace SAF Submission Ingestion Package generated from Vireo submission #22652 on 2025-10-25 at 15:54:21Multilingual employees have become an integral component of organizations in the United States (U.S.). This has made English Language communication competence an essential skill in U.S. organizations. There are Non-native English-speaking (NNE-speaking) employees from Global South countries who are experts in what they do, but not fluent in English language use or accented. There is limited empirical research in the field of Human Resource Development (HRD) that examines how everyday communication influences the workplace experiences and career development of NNE-speaking employees. Therefore, this study examined how the communicative competence of NNE employees is used to gauge the performance of NNE-speaking employees despite their level of expertise, the acceptance of the employees, stereotypes towards the employees, organizations' interventions, and the effectiveness of the interventions on NNE-speaking employees’ inclusion and career development. This research is situated in Critical HRD, using critical perspectives in HRD and guided by stigma theory. Critical perspectives in HRD are theoretical viewpoints that challenge traditional approaches to HRD by focusing on issues of power, inequality, and social justice, advocating for systemic change. An explanatory sequential mixed-methods design was used for this study. For the quantitative phase of the research, survey data of 163 NNE-speaking employees who work in Fortune 500 Organizations, from Global South countries, and who had migrated to the U.S. as adults, that measured the impact of communicative competence on workplace acceptance, performance perception, career development, perceived stereotypes, and impact of training was collected and analyzed. Multiple linear regression analysis showed that communicative competence scores were significant positive predictors of acceptance, performance perception, and self-reported career progression of NNE-speaking employees in these organizations. For the qualitative phase, in-depth interviews were conducted with 20 purposively selected survey respondents. Reflexive thematic analysis was used to analyze data. Findings revealed that the communication competence of NNE-speaking employees was interpreted as reduced professional competence, and NNE-speaking employees experienced partial acceptance, exclusion, stereotypes, underestimation, and low performance expectations, which often led to participants resorting to engagement in extra self-development, code-switching, or accent softening, and NNE-speaking employees working twice as hard to prove expertise. Integration showed that communication competence impacts NNE speakers’ career development in both phases, with qualitative findings corroborating the quantitative findings and contextualizing it through rich narrated experiences, and culturally matched mentorship, standing out as the most valuable intervention. This study advances HRD scholarship by offering practitioner-aligned implications for practice aimed at fostering more equitable workplaces and positively influencing the career trajectories of NNE-speaking employees in corporate America. It also provides implications for research that contribute to the advancement of communication-focused and linguistically inclusive critical HRD research