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OCCUPANCY AND ECOLOGICAL INFLUENCE OF SEMI-AQUATIC MAMMALS IN SOUTHERN ILLINOIS
No full textSemi-aquatic mammals play important ecological roles at the interface of terrestrial and aquatic systems. Specifically, beavers (Castor canadensis) and muskrats (Ondatra zibethicus) can modify habitat through ecosystem engineering behaviors whereas the presence of river otters (Lontra canadensis) and mink (Neovison vison) can be indicative of overall habitat quality. Given these roles, advancing our understanding of how environmental factors shape their occupancy and how semi-aquatic mammals themselves may influence surrounding communities would strengthen conservation efforts. To address this, I surveyed 67 sites across four counties in southern Illinois, USA from March – May 2023 for American beaver, muskrat, river otter, and American mink. Sites were distributed evenly between waterbody type and size. Given the elusive nature of these species, I combined two detection methods, sign surveys and camera traps, to increase detection. In chapter 1, I applied a Bayesian multi-method occupancy model that incorporates both detection methods to estimate a single occupancy probability for each target species to determine the relative importance of terrestrial and aquatic environments to semi-aquatic mammal distributions. I built candidate models of aquatic and terrestrial covariates separately to identify the most important covariates of each category. The individual top model varied by species, but a combined additive model of the top aquatic and terrestrial models provided the best overall predictions for each species. Beaver, otter, and mink occupancy showed positive associations with large waterbodies, while muskrat occupancy was positively linked to lotic systems. Additionally, muskrat and mink occupancy were positively related to increasing distance from roads. These results suggest that while aquatic and terrestrial factors have varying influences in predicting semi-aquatic mammal occupancy, considering both yields the most accurate results. All four semi-aquatic mammal species I studied were impacted by aquatic type, highlighting the importance of considering both waterbody types to better understand their distribution. In chapter 2, I quantified measures of alpha and beta diversity of terrestrial mammals detected by camera traps to measure the influence of beaver and muskrat on species diversity. I then used distance-based redundancy analysis to model diversity as a function of beaver and muskrat occupancy probability, as well as the presence of a beaver dam. The basic measure of alpha diversity, species richness, was not influenced by beaver, beaver dams, or muskrat occupancy in any of the models. Beaver dams and muskrat occupancy had a negative effect on total beta diversity and the species turnover component of beta diversity. This suggests that both beaver dams and muskrat are influential in maintaining consistent species compositions, perhaps due to the habitat modifications both enact on the landscape. Overall, this work contributes to a greater understanding of how semi-aquatic mammals interact with the landscape and surrounding communities
TOO BIG TO FAIL? USING MICROSATELLITES TO EXAMINE THE POPULATION GENETICS OF FLATHEAD CATFISH (PYLODICTIS OLIVARIS) IN MISSOURI IMPOUNDMENTS
No full textFlathead Catfish (Pylodictis olivaris) is a popular sportfish managed for recreational and commercial uses. Currently, managers in Missouri have implemented various reservoir-specific bag and length limits for P. olivaris to create sustainable populations of quality-sized individuals available for anglers to capture. In conjunction with field studies to estimate growth rates and size/age distributions, I developed and scored 15 microsatellite markers to estimate the effective population (Ne) and population structure within 10 Missouri reservoirs. I assessed the power of the markers to get acceptably precise estimates of Ne using NEoGen assuming life-history parameters (e.g., age at maturity, longevity and fecundity) estimated from the literature. I then used the individuals collected from a single reservoir to conduct a sibship and parentage analysis. These results combined with previously published life-history parameters were used to conduct population models to estimate the effects of fishing mortality and changes to length limit regulations. Results from the simulations run in NEoGen indicated that genotypes from at least 60 catfish were required to attain precise estimates of Ne when the true Ne was 30 while Ne values of 100 or more were estimated to require sample sizes \u3e100. Current Ne results show that smaller sampled reservoirs have an Ne of less than 50 while larger reservoirs had an estimated Ne of \u3e100. Results also suggest there is little population structure within larger reservoirs (Table Rock: FST = 0.025, Truman: FST = 0.024) indicating that a single estimate of Ne is sufficient for the entire reservoir. Results from the sibship and parentage analysis suggest there is a higher reproductive variance for male than female P. olivaris. Finally, the modelling results indicated that minimum length limits resulted in the largest total population size (N) and Ne; while increases in fishing mortality resulted in decreases in the N and Ne. The results of this study will help managers choose the best strategies for specific reservoirs to maintain flathead catfish populations with desirable size structure
The Epistemological Dimension of Dewey’s Emergentist Metaphysics: Sense and Signification
No full textI argue that Dewey had a kind of naturalistic or pragmatic epistemology already in his Experience and Nature which constitutes the Pragmatic Epistemology View. Dewey’s naturalistic epistemology is exemplified by his theory of “sense” and “signification” and as such is the first order consequence of Dewey’s second order qualitative naturalism. Instead of the classical epistemological question, “How is knowledge possible anyway, überhaupt?”, Dewey’s pragmatically reconstructed version of it would be “How do we make sense of the world that is around us?” Instead of the classical “theory of knowledge,” Dewey’s pragmatic epistemology can be seen as a theory of sense-making
Some explicit descriptions of characters stabilizing smooth complex representations of GL(r, D) with a p-adic division algebra D
No full textFor a positive integer r and a central division algebra D over a non-archimedean field F of characteristic zero, we provide an explicit and precise description of (the number of) characters that stabilize irreducible smooth complex representations of GL(r,D). The works of Gelbart-Knapp and Hiraga-Saito on L-packets for inner forms of SL(n) over the p-adic field are being mainly applied, and we also explicitly discuss that there are some representations that have multiplicity that are different than 1
Mapping Cardiac Adipose Tissue Using Spectral Analysis of Ultrasound Radiofrequency Data and Machine Learning
No full textCardiovascular disease (CVD) remains the leading cause of mortality worldwide, accounting for over 20 million deaths annually. Among these, coronary artery disease (CAD) is responsible for approximately 9.44 million deaths in 2023 alone, and its prevalence is expected to increase from 48% in 2022 to over 50% in 2030. With CVD affecting nearly one in two individuals in the United States, there is an urgent need for accessible, non-invasive diagnostic tools to support early detection and risk stratification.Cardiac adipose tissue (CAT), the visceral fat surrounding the myocardium, has emerged as a promising biomarker for both CVD and CAD. Elevated CAT depositions near the coronary arteries is linked to plaque formation and adverse cardiovascular events. Although magnetic resonance imaging (MRI) offers accurate visualization of CAT, its high cost and limited availability restrict its widespread clinical use. In contrast, standard echocardiography or ultrasound (US) is more accessible and cost-effective but currently limited to linear measurements of CAT on the right ventricular free wall, lacking the capability for comprehensive assessment. This dissertation investigates the hypothesis that spectral analysis of raw US radiofrequency (RF) data can be used to identify and map CAT in echocardiograms. To test this hypothesis, we propose a fully automated, low-cost imaging framework that integrates RF data analysis with machine learning (ML) and deep learning (DL) techniques. The approach enables segmentation of epicardial contours from parasternal short-axis (PSAX) US images, classification of CAT regions using spectral features, and mapping of CAT distribution around the heart’s perimeter. To validate the segmentation component, state-of-the-art DL models—including the Segment Anything Model (SAM), Detectron2, and U-Net with ResNet backbones—were evaluated. These models achieved an average Dice Similarity Coefficient of 0.82 and a Hausdorff Distance of 4.93, indicating strong performance in delineating epicardial boundaries. For CAT mapping, ground truth labels were derived by intersecting 3D heart models reconstructed from MRI data with corresponding US scans. The heart perimeter was divided into regions of interest (ROIs), which were labeled based on varying CAT thresholds from MRI-derived maps. ML classifiers were trained to predict CAT presence in each ROI using spectral parameters extracted from the RF data. The highest classification precision of 74.22% was achieved using RUSBoosted tree ensembles at a CAT threshold of 85%. Our findings demonstrate that DL models are effective for segmenting left and right ventricular contours in PSAX echocardiograms. Specifically, models trained on domain-specific datasets, such as U-Net with ResNet, outperform general-domain models when applied to small, locally acquired datasets. Furthermore, the proposed CAT mapping approach significantly enhances the identification of CAT in regions not typically visible in grayscale US images. By leveraging spectral information, this method enables a more comprehensive assessment of CAT using US alone. This research contributes a radiation-free, MRI-independent technique for CAT quantification, making it suitable for patients with metal implants (e.g., pacemakers, joint replacements) and those in resource-limited settings. Ultimately, the proposed framework supports improved risk stratification for heart attacks and lays the groundwork for future studies exploring the relationship between CAT distribution and coronary plaque characteristics in CAD progression
School Attendance in Southern Illinois: A Mixed Methods Analysis of Trends and Implications
No full textThe purpose of the study was to examine the demographic data reported on the Illinois School Report Card within the four southernmost Regional Offices of Education to determine the rates of chronic absenteeism. Following the identification of chronic absenteeism numbers, this study sought to analyze the relationships between subgroups to determine correlations within data sets. In order to develop an understanding of potential interventions, interviews were conducted with districts that were both successfully addressing absenteeism and those not experiencing success within each of the Regional Offices of Education. The findings of the study aim to contribute insights for educators and administrators to establish robust attendance policies and programs at the younger grades to impact future attendance trends
Current Behavior Analytic Research on Assent and Assent Withdrawal of Students with Disabilities
No full textThe field of behavior analysis is ever-evolving, just as the seven dimensions of applied behavior analysis have instructed it to (Baer et al., 1968). Over time, certain procedures, such as electric shock, spanking, and restriction of movement (Leaf et al., 2021), have become unethical, which has resulted in modifications to the Ethics Code for Behavior Analysts (Behavior Analyst Certification Board, 2020), as well as everyday practice to ensure these unethical interventions are no longer utilized. Despite these advances, there are still areas that are lacking in the field. Therefore, the current paper will review the literature in behavior analysis that relates to assent, autonomy, self-determination, trauma-informed care, and various areas that branch from those topics, such as adverse childhood experiences, compassion, coercion, and more. To date, the literature is scarce and underscores the need for more research to be conducted related to the topics of assent and assent withdrawal from a behavior analytic perspective
U.S. Bison Industry: An Analysis of Production, Health, and Market Dynamics
No full textThe bison market has been becoming increasingly popular within recent years. However, this market is challenging for producers due to disease concerns, aggressive bison behaviors, nutritional and facility requirements and market risks for bison operations. Since most bison data began in 2020, forecasting bison meat prices remains difficult. This raises an important question: can bison meat cut prices be effectively hedged by using live cattle futures prices? This paper examines USDA bison meat cut price data and live cattle futures prices to determine potential correlations. A regression analysis, along with a dummy variable approach is utilized to evaluate the relationship. The results suggest that bison producers may be able to mitigate price changes by using live cattle futures as a hedging tool
DECOLONIZING EDUCATION: TRACING THE DEWEYAN ROOTS OF KWAME NKRUMAH’S EDUCATION POLICIES IN GHANA, 1951-1966
No full textThe mid-twentieth century marked a watershed in the history of African education. The period saw a movement by African nationalists to liberate education from European colonial rule, particularly in territory known as the Gold Coast, present-day Ghana. Kwame Nkrumah, a leading nationalist who later became the national leader of the country, first articulated a radical departure from colonial policy in Ghana, which became the blueprint for similar structures in other colonial areas across the continent. This study examines the colonial education system established by the British authorities. This system was designed to produce individuals who would assist in British administration, speak English, and perform basic arithmetic. Influenced by Dewey’s broader goals of national development, this study investigates the impact of Dewey on Nkrumah’s philosophy. Nkrumah believed that his system was appropriate for fostering self-determination and sought to create an education system that would cultivate independent thinking, responsibility, and challenge the authority of colonial Indirect Rule. Using archival materials, textbooks, and online articles, the study examines British colonial education in Nkrumah’s post-colonial education policies. Additionally, the study examines the influence of Deweyan thought on Nkrumah’s educational policies, their implementation, and the impact of Nkrumah’s reforms
Mechanobiological Regulation of NF-κB in Innate Immunity
No full textMechanotransduction is a process through which cells sense and respond to mechanical stimuli, converting them to biochemical signals. The innate immune system plays a role by integrating biochemical signals through cell signaling pathways to safeguard against viral infections. One of these pathways is the mechanosensitive NF-κB signaling pathway. Although this pathway has been widely studied in immunology, its regulation through mechanotransduction has been largely unexplored. Recent work from our group explains the mechanotransduction of the RIG-I pathway upstream of the NF-κB pathway. This study aims to find the role of NF-κB mechanotransduction in innate immune antiviral signaling. We hypothesize that there is a crosstalk between this pathway and the RhoA/ROCK pathway, controlling the immune response based on substrate stiffness. To maintain the mechanical response of the cells, we seeded HeLa cells on polyacrylamide (PAA) hydrogels with stiffness levels of 0.6 kPa and 8.5 kPa. We used Poly (I:C), a synthetic viral mimic, to transfect the cells, triggering the NF-κB and RIG-I pathways. We also used Shikonin (SHK), a suppressor of NF-κB, to study its role in mechanotransduction. A series of traction force microscopy (TFM) experiments were performed. Preliminary data show that SHK suppresses the stress response from the cells, indicating a reduction in viral immune response. This finding, supported by an immunofluorescence study with NF-κB p65 antibody, demonstrates that the NF-κB acts as a mechanotransduction pathway, creating a homeostasis between mechanical and chemical immune responses