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LINEAR OPERATORS WITH TWO INVARIANT SUBSPACES
No full textLet k be a field and n ∈ N. We consider the quadruples (V, U’, U”, T) where V is a finite-dimensional k-vector space, U’ and U” are subspaces of V , and T : V → V is a linear operator with Tn = 0, satisfying T(U’) ⊆ U’ and T(U”) ⊆ U”. We say U’ and U” are invariant under T and T acts nilpotently on V with nilpotent index n. These systems of quadruples form a category with the Krull-Remak-Schmidt property. Thus, classification is reduced to the classification of indecomposable systems.
By translating a seemingly intractable linear algebra problem to that of module theory and quiver representations, we are able to utilize Auslander-Reiten Theory to aid our analysis. We will give a complete classification in this work. The nilpotent index is crucial for classification of the category. For n ≤ 3, our problem is classifiable. For n \u3e 3, our category is of wild representation type, and no complete classification can be done. For n = 1, 2 we will list the finitely many indecomposables, and for n = 3, we will give a complete description.
In particular, we demonstrate that S(3) is a tubular category of type E6 and explicitly construct its exceptional tubes. We provide a complete classification of dimension triples in N3 corresponding to indecomposable quadruples in S(n), together with visualizations. Furthermore, we identify all Gorenstein-projective modules in these categories, finding 9 such modules in S(2) and 27 in S(3). Finally, we present an application of these results in the context of linear time-invariant dynamical systems
SAFETY IN STABILITY: A CDC-GUIDED EVALUATION OF HOSPITAL FALL PREVENTION PRACTICES
No full textHospital falls remain a persistent and preventable cause of patient harm, emphasizing the need for continuous evaluation of fall prevention practices. This project assessed the effectiveness of AdventHealth Orlando’s fall prevention policy using the Centers for Disease Control and Prevention (CDC) Program Evaluation Framework. A mixed-methods design incorporated quantitative analysis of 12 months of fall data and qualitative feedback from frontline staff surveys and discussions. Results demonstrated a decrease in total falls from 549 in the previous year to 528 in the current year, indicating early progress despite the incomplete reporting period. Unit-level analysis showed a mean improvement of 16.9% following the most recent intervention rollout, though variability across service lines revealed inconsistencies in policy adherence and implementation. Staff feedback highlighted barriers such as workflow challenges, inconsistent training, and patient non-compliance, as well as opportunities to enhance the use of standardized tools, proactive toileting, visual cues, and individualized care planning. Guided by Sister Simone Roach’s Six C’s of Caring and the CDC evaluation standards, this project generated evidence-based recommendations to strengthen fall prevention strategies, improve staff competency and engagement, and support organizational goals for patient safety and Magnet readiness. Findings underscore the importance of replicable program evaluation processes, continuous quality monitoring, and compassionate, evidence-driven nursing practice to reduce inpatient falls and promote a culture of safety
ASSESSING THE ROLE OF LEAD AND WAX SHIELDING IN ELECTRON BEAM DOSE TO FACIAL TISSUE
No full textExternal Beam Electron Therapy is frequently used to treat facial cancers. Wax and lead shields protect the eye lens and adjacent structures, reducing long term-complications and exposure to healthy tissues. Although these materials attenuate radiation behind the shielding, their impact on surface dose to nearby tissue requires further investigation.
This project evaluated how shielding materials influence surface dose to facial structures using MOSFET detectors on a paraffin wax phantom developed from a patient’s Dot Decimal compensator. Relative surface doses were compared for 6MeV and 9MeV electron beams under varying wax and lead shielding configurations. Results indicate that while wax and lead eye shields reduce dose to the eye, they can increase dose to the ala. Gamma putty nose plugs increased the dose up to 91% to the anterior nostril and reduced dose to the posterior nostril by 87% as compared to no shielding
INTERPRETABLE MACHINE LEARNING FRAMEWORKS FOR DETECTING AND CHARACTERIZING ADAPTIVE PROCESSES IN GENOMIC DATA
No full textDetecting genomic regions influenced by adaptive processes is fundamental to understanding adaptation and its connection to modern human traits. Traditional summary-statistic and likelihood methods capture only simple evolutionary scenarios, while deep learning models such as convolutional neural networks, though powerful, often lose spatial information and lack interpretability. This dissertation introduces three complementary frameworks that overcome these limitations by integrating interpretable machine learning with spatially structured genomic data. The first framework, T-REx employs tensor decomposition to extract informative features from haplotype alignment images, enabling accurate classification of selective sweeps with classical learning models. The second framework, α-DAWG applies wavelet and curvelet decompositions to capture directional and frequency-based signatures of selection, achieving performance comparable to convolutional neural networks while remaining interpretable and robust. The third framework, SKINET introduces a trend-filtered kernel within a support vector machine, preserving spatial autocovariation and extending to quantitative inference of adaptive parameters. Applied to human genomic data, these frameworks not only detect classical signature of selective sweeps such as LCT and MCM6 but also uncover novel candidates including FAM177A1 and PTPRJ that reveal interesting disease associations. Collectively, these methods demonstrate that interpretable, structure-aware machine learning frameworks can advance the frontier of adaptive inference by combining predictive power with evolutionary insights
SAMPLING GEAR PERFORMANCE AND ELASMOBRANCH DISTRIBUTIONS IN THE UPPER FLORIDA KEYS
No full textElasmobranchs (sharks, skates, and rays) are vital marine predators, yet many populations are declining from overfishing and habitat loss. Marine protected areas like the Florida Keys National Marine Sanctuary (FKNMS) can support recovery, but knowledge gaps remain in habitat-specific community structure and survey effectiveness. I surveyed inshore (seagrass, hardbottom) and offshore (patch reef, bank reef) habitats in the Upper Florida Keys using longlines, drumlines, baited remote underwater video (BRUVs), and unmanned aerial vehicles (UAVs). Inshore assemblages showed strong habitat-driven patterns, with Ginglymostoma cirratum dominating seagrass sites, whereas offshore reefs were more homogeneous. UAVs captured the highest inshore richness, and drumlines outperformed BRUVs offshore, highlighting complementary strengths of multi-method approaches. These findings provide critical baselines and emphasize the need for long-term, spatially extensive monitoring that incorporates seasonal dynamics and the movement ecology of large, threatened elasmobranchs
INVESTIGATING HOW EVOLUTION HAS AFFECTED THE NEUROANATOMY OF ADULT ASTYANAX MEXICANUS
No full textThe topology of the brain is highly conserved across phyla, yet the evolutionary processes driving anatomical divergence remain poorly understood. The fish Astyanax mexicanus, which exists in both surface- and cave-dwelling morphs within the same species, provides a powerful model for studying brain evolution. While previous studies have focused on larvae, imaging adult brains has been challenging due to their size and opacity. This study overcame these limitations using tissue clearing, light sheet imaging, and computational analysis to generate a comprehensive adult brain atlas. Using nuclear staining and antibody labeling, brain-wide 3D maps were created to compare regional size, shape, and molecular identity across surface fish, cavefish, and F2 hybrids. In parallel, behaviorally induced neuronal activity was mapped using pS6 immunolabeling following a stress-based novel tank diving assay. These findings reveal how genetic and environmental factors shape adult brain structure and activity, offering new insights into the evolution of neuroanatomy and behavior
DOES THE ACQUISITION OF SPANISH AFFECT THE ACQUISITION OF ENGLISH? A LONGITUDINAL STUDY OF MINORITY-MAJORITY SIMULTANEOUS BILINGUAL DEVELOPMENT FROM 2.5 TO 12 YEARS
No full textPast work with bilinguals suggests that the acquisition of one language has an impact on the acquisition of another. What is unclear is the direction and strength of the relation between the two languages and whether the relation changes with age. Participants were children in South Florida who heard both Spanish and English at home. They were assessed in expressive (from 2.5 to 12 years) and receptive vocabulary (from 4 to 12 years). Both concurrent bivariate correlations and bivariate splines were used to evaluate the cross-language relations. Results suggest that early in acquisition the two languages compete for resources, but after the age of 4 years, the only observed negative relations between one language and the other was a negative effect of growing expressive English skill on the future growth of Spanish expressive skill. English and Spanish receptive vocabulary growth are consistently positively related from 4 to 12 years
SAFE AND SOUND: A POLYVAGAL INTERVENTION FOR TRAUMA AND THERAPEUTIC ENGAGEMENT
No full textPosttraumatic Stress Disorder (PTSD) affects approximately 5 to 8 percent of the U.S. population annually, contributing to significant healthcare costs and high psychotherapy dropout rates (Kessler et al., 2005; Kilpatrick et al., 2013; National Center for PTSD, 2023a). Understanding the factors that contribute to treatment attrition and identifying effective interventions that promote safety, engagement, and sustained participation in therapy are critical priorities in trauma counseling.
This study examined the impact of a polyvagal theory-informed intervention, the Safe and Sound Protocol (SSP), on trauma symptoms, autonomic reactivity, and the quality of the therapeutic relationship in adult clients diagnosed with trauma- and stressor-related disorders. The SSP is a non-invasive acoustic vagal nerve stimulation intervention designed to regulate the autonomic nervous system and support a neurophysiological state of safety (Unyte Health, 2023a). A single-case research design was utilized to evaluate outcomes across a baseline, intervention and maintenance phase. Standardized measures of trauma symptomology, autonomic nervous system functioning, and therapeutic engagement were administered at multiple time points to assess change over time. Visual analysis and Tau-U effect size calculations indicated clinically meaningful improvements in trauma symptom reduction and autonomic regulation during and after the intervention. SSP did not appear to impact the quality of the therapeutic relationship.
Findings from this study provide preliminary evidence that polyvagal-informed interventions such as the SSP may reduce trauma symptoms, improve autonomic regulation, and enhance treatment retention. By supporting clients in achieving a regulated physiological state, the SSP may serve as a valuable adjunct to trauma counseling, mitigating dropout risk and promoting sustainable therapeutic change
MICROCRYSTALLINE WAX LAB SCALE ASSESSMENT AS CORROSION PROTECTION IN POST TENSIONING CONSTRUCTION SYSTEMS
No full textThe primary focus of this project is to assess the effectiveness of five different flexible fillers in preventing corrosion-induced failures, particularly when exposed to water and chloride containing solutions. The specimens tested are single steel wires that ranged from (12-16cm) in length and 7 mm in diameter.
Samples are monitored to study the impact of factors like water and chloride solution concentration to identify when and which one could cause corrosion to initiate when the steel wires are coated with different flexible fillers. The goal is to identify the types of flexible fillers that protect the steel wires from corroding for better durability and safety of post-tensioned structures in various industries
THEY WHISPERED, HANDS OVER THEIR MOUTHS: STORIES
No full textThe stories in this collection are a mixture of explorations into the ineffable nature of memory and time, and reflections on such themes as redemption, loyalty, institutional and political violence, power and oppression, loss, regret, and exile.
The characters are at times disaffected, at times hopeful, at times oblivious to the causes of their plight. They are marginal, and struggling to keep head above water, on the edge of despair, holding tightly to the lifesaver thrown by a word, a memory, an image of solace. Above all, they are the estranged, the economically and emotionally vulnerable, yet resilient, fighters, faithful, believers in the power of redemption. These characters do their best to finish the day unscathed, and whatever realization they happen to stumble upon after the day is done, are enigmas in whose company they learn to live.
The settings of most stories are sometimes sketched, barely outlined, enveloped by the fog of remembrance. Sometimes, they are concrete, grounded, commonplace, quotidian and familiar, evoking a silent camera panning on landscape scenes taken from a documentary. Most of the scenes take place in small, unnamed Andean towns, but the narrative elements, themes and motifs, suggests a Latin-American country; however, the scenes and characters could be taken from anywhere else –the reader decides.
During the time I was writing these stories, I lost my mother, and she lost her mother and sister. During this time, my daughter was born miles away from them. So, it was unavoidable that the meditations on life, time, exile, and redemption work their way into the worlds of some of the stories presented here. With this in consideration, one may say that the stories in They Whispered, Hands Over Their Mouths: Stories are also a reflection on the fleeting nature of existence and change, personal and collective