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Phylogenetic Comparative Analyses of Avian Elevational Ranges, Sex Differences, and Symbionts
No full textIn this dissertation, I investigate drivers of adaptive evolution across spatial, temporal, and phylogenetic scales. Using a blend of fieldwork, morphological and physiological data, comparative analyses, and evolutionary modeling, I identify hidden constraints and eco-evolutionary signatures shaping avian diversity. In Chapter 1, I examine how Neotropical bird elevational ranges have shifted over deep time. Chapter 2 explores sexual dimorphism in Sandhill Cranes, showing how interactions between natural and sexual selection can modulate sex differences. Chapter 3 focuses on a novel form of cryptic sexual dimorphism, asking how different axes of sex-based trait divergence interact. Chapter 4 shifts to the community scale, treating biotic communities as host traits by characterizing the lung mycobiome of a North American bird assemblage and assessing patterns of host-microbe association. Together, these chapters offer an integrative view of how selection and constraint shape phenotypic and ecological diversity in birds
UPCYCLING OF POLYDICYCLOPENTADIENE (pDCPD) VIA DYNAMIC BONDS
No full textThermoset polymers are valued for their exceptional mechanical strength and thermal stability, but suffer from irreversibility due to permanent covalent crosslinks, limiting recyclability. Polydicyclopentadiene (pDCPD), a widely used thermoset, exemplifies this limitation despite its excellent mechanical properties. In this study, we report an upcycling strategy for pDCPD through the incorporation of dynamic imine bonds. The successful integration of imine bonds was confirmed by ¹H NMR spectroscopy. Mechanical testing revealed that the modified pDCPD (pDCPD-imine) exhibits enhanced tensile strength and maintains its performance across multiple reprocessing cycles. Moreover, the dynamic nature of the imine bonds imparts healability to the network. This approach addresses a key limitation of conventional thermosets and offers a pathway to extend their functionality and service life through dynamic covalent chemistry
Effect of tRNA synthetase inhibitors on aging in Caenorhabditis elegans
No full textAging is a multifaceted biological process characterized by the progressive decline in physiological integrity, ultimately leading to impaired function and increased vulnerability to disease. One emerging aging intervention involves the modulation of the Integrated Stress Response (ISR) via the transcription factor ATF-4, a conserved regulator of longevity across species. This dissertation investigates the effects of tRNA synthetase inhibitors- compounds that activate ATF-4 signaling- on lifespan and healthspan in Caenorhabditis elegans. I hypothesize that tRNA synthetase inhibition will lead to increased lifespan, healthspan, and autophagy in C. elegans in an atf-4-dependent manner. This work supports a conserved mechanism of longevity via translational control of ATF-4 and highlights tRNA synthetase inhibitors as a promising new class of geroprotective compounds
LOCALIZATION OF ALPHA POWER DEFICITS IN FIRST EPISODE PSYCHOSIS
No full textThe purpose of this study was to determine where in the brain there may be a difference in brain activity in patients during their first episode of psychosis (FEP) compared to healthy controls (HCs) while performing an auditory oddball task. Time-frequency analysis allows for spectral decomposition where the signal measured by magnetoencephalography (MEG) is used to characterize changes in neural oscillations and their synchronization over time and region. Previous EEG studies report reduced alpha (8-12Hz, 70-160ms) power but most studies focused on patients with chronic schizophrenia and with limited source localization
Leveraging Attention Mechanism to Unlock Gene and Protein Attributes
No full textAdvancing personalized medicine depends on effectively integrating and interpreting the vast, heterogeneous landscape of biological data, from genomic sequences and transcriptomics to the insights embedded in scientific literature. Current machine learning models often focus on single data modalities, limiting their capacity to capture the multifaceted nature of biological systems. We address this gap by developing three attention-based machine-learning models integrating diverse data modalities. Firstly, DeepVul is a multi-task model that leverages cancer transcriptome data to predict genes critical for cancer survival and their corresponding drugs. Subsequently, LitGene refines gene representations by integrating textual information from the scientific literature. Finally, Protein2Text is a large language model that translates protein sequences into natural language descriptions, making complex biochemical data accessible and interpretable. These models echo a comprehensive approach to integrating various data modalities to provide an alternative view of biological systems, paving the way for truly personalized medicine for everyone
Seeking Structure in Complex Systems: From Feature Analysis to Space-Time Causal Discovery with Earth Science Applications
No full textComplex systems are difficult to study because of their many interacting parts, emergent phenomena, and feedback loops. These systems underpin all life on Earth. We need improved tools for seeking an understanding of them. This body of research presents my investigations into data-driven methods for understanding complex systems, including my invention of a novel causal discovery meta-algorithm for space-time gridded data. I demonstrated machine learning feature importance and causal discovery capabilities for comparing simulated and observed climate data. I developed a new benchmark for modeling space-time dynamics of locally driven phenomena and examined a prominent causal discovery algorithm. Finding that contemporary causal discovery struggles with the high-dimensionality of space-time gridded data, I developed CaStLe, a causal discovery meta-algorithm for recovering the space-time evolution of advective phenomena. Finally, I extended CaStLeto recover multivariate space-time dynamics. This research enhances scientists\u27 capabilities to explore and understand complex systems in our universe
Composition Portfolio
No full textTo fulfill the requirements of the UNM Master Theory-Composition Program, this thesis portfolio includes the following pieces:
Eco IV, for oboe, Bb clarinet, alto saxophone, bass clarinet, and bassoon. This piece explores my concept of meta-instrument, which combines two or more
instruments to create a new one. In Eco IV I explored proportional notation, impulses, attacks, elision in gestures, pitch order, transitions, and noise. The piece was
performed by Splinter Reeds at the 2023 John Donald Robb Composer´s Symposium. With this work, I fulfill the requirement of a work using orchestra, chamber
orchestra, or wind ensemble.
Quotations, for flute, alto saxophone, baritone saxophone, tuba, percussionist, two pianos, voice, viola, two violoncellos, and double bass. This piece sets
text by Latin American writers such as: Alejo Carpentier, Juan Rulfo, Augusto Monterroso, Gabriel García Marquez, and Julio Cortázar. In Quotations I develop
my concept of meta-instrument in coherence with the lyrics. The piece was performed by the New Music New Mexico ensemble in the Fall of 2024. With this
work, I fulfill the requirement of a work using sung or spoken voice.
Metamorphosis, for flute and max. This piece uses buffer sounds to create a dialogue with the solo instrument. In order to do this, I created a Max patch. The
piece is dedicated to Jesse Tatum, and it will be premiered in the Spring of 2025. With this work, I fulfill the requirement of a work using electronics.
The Five Gazes of the Phoenix for film and fixed media. The piece transforms into sound as a natural reaction of the movements of the images. The piece
uses sounds made by a synthesizer. I wrote this piece in the Latin American Electronic Music Composition in the Spring of 2024. With this work, I fulfill the
requirement of a work that is inter-disciplinary
A COMPARATIVE SUBNATIONAL POLICY ANALYSIS OF STATE COVID-19 VACCINE POLICIES AND APPLICATION OF THE POLITICAL DETERMINANTS OF HEALTH MODEL
No full textA COMPARATIVE SUBNATIONAL POLICY ANALYSIS OF STATE COVID-19 VACCINE POLICIES AND APPLICATION OF THE POLITICAL DETERMINANTS OF HEALTH MODEL
By
Demetrius Cianci Chapman
Associate of Science Nursing, Jewish Hospital College of Nursing and Allied Health, 1998
Bachelor of Science of Nursing, Saint Louis University, 2000
Master of Public Health, Saint Louis University, 2004
Master of Science Nursing (Research), Saint Louis University, 2004
Doctor of Philosophy, Nursing, University of New Mexico, 2025
ABSTRACT
This study uses the political determinants of health (PDoH) framework to analyze state-level COVID-19 vaccine policies and their impact on population health. The PDoH model examines how structured relationships, resource distribution, and power dynamics shape health equity. The analysis compares policies mandating vaccines for state workers, banning mandates, and regulating vaccine passports. Data were drawn from public sources, excluding human subjects. Findings show that lower voter turnout and Democratic Electoral College votes increased the likelihood of vaccine mandates and decreased the likelihood of passport bans. States with Medicaid expansion were less likely to ban mandates, though policy variables did not reliably predict mandate bans. Democratic control raised the odds of vaccine mandates by 13.57 times, but did not affect passport policy adoption. Higher median income was the only consistent predictor of both vaccine mandates and administration rates. State party control, income, and rural population percentages were key influencing factors
Exploring the very early cosmological history with dark matter and primordial black holes
No full textWe explore the possibilities of nonstandard early cosmological histories and their potential roles to explain DM. We study how particle DM is produced with scenarios of early matter domination (EMD), how primordial black holes (PBHs), which could also be a DM candidate in certain mass ranges, are formed with enhanced curvature perturbation or FOPT and the corresponding gravitational wave (GW) signals, how PBHs could increase their mass by accretion during EMD and the corresponding GW signals
A Systematic Approach to the Characterization of Liquid-Vapor Coexistence in Platinum
No full textPlatinum is a material standard used in high pressure and shock compression experiments at Sandia National Laboratories. During experiments, materials are subjected to a very large range of thermodynamic conditions, during which materials regularly enter the liquid-vapor coexistence region. Despite its status as a standard, the region around the liquid-vapor critical point is poorly understood for platinum, with reported critical temperatures spanning approximately 7000 K. In this dissertation we conduct density functional theory based molecular dynamics (DFTMD) simulations for platinum for a range of temperatures and densities near liquid-vapor coexistence. The phase diagram for platinum is refined near the critical point using two independent techniques for analyzing the DFTMD data. We find that the two approaches result in a critical point and liquid-vapor phase boundary that agree well. Additionally, our analyses agree within error with recent experimental measurements of the liquid side of the phase boundary of platinum