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Moose (Alces Alces) Herbivory Is The Main Driver Of Spatial And Temporal Variation In The Nitrogen And Carbon Content Of Balsam Fir Foliage, Jasmine Fairbanks Terry-Shindelman

Dissertations, Master's Theses and Master's Reports

To adequately manage forested ecosystems in the face of climate change, there is an urgent need to study how tree growth and biochemistry vary in response to changes in weather and levels of herbivory across different landscape types. However, few studies have assessed how both free-ranging herbivore populations and weather influence the foliar chemistry of boreal tree species over relatively large temporal and spatial scales. In this study, I assessed the extent to which the nitrogen (N) content and the carbon-to- nitrogen (C/N) ratio in the foliage of Balsam fir (Abies balsamea), a key boreal forest species, was …

Fine Root Respiration In Quercus Rubra Is Influenced By Multidimensional Trade-Offs In Root Trait Space, Emma L. Shedd

Dissertations, Master's Theses and Master's Reports

Economic theory is often applied to plant strategies, arguing that trade-offs exist between maximizing quick returns on investment within short lifespans or producing longer-lived tissues with slower returns. While these trade-offs are well-studied aboveground, their influence on belowground traits, including root respiration, remains unclear. Resource heterogeneity and symbioses with mycorrhizal fungi may complicate root trade-off axes beyond those predicted by economics theory alone. Investigating fine root trade-offs in Quercus rubra populations along a latitudinal gradient in the Midwest, USA, we identified two distinct axes of variation in root traits: one related to a potential “fungal symbiosis” trade-off and another representing …

Statistical Methods For Gwas And The Impact Of Diabetic Medication Adherence On Healthcare Costs, Meida Wang

Dissertations, Master's Theses and Master's Reports

This dissertation includes three Chapters. In Chapter One, we develop a computationally efficient clustering linear combination approach to jointly analyze multiple phenotypes for GWAS. In this paper, based on the existing CLC method and ACAT strategy, we develop the ceCLC method to test association between multiple phenotypes and a genetic variant. In Chapter Two, we develop a novel method called sCLC for association studies of multiple phenotypes and a genetic variant based on GWAS summary statistics. Simulation results show that sCLC can control Type I error rates well and has the highest power in most scenarios. In Chapter Three, we …

Covid-19 And Pregnancy: Clinical Outcomes; Mechanisms, And Vaccine Efficacy, Deepak Kumar, Sonam Verma, Indira U Mysorekar

Faculty, Staff and Students Publications

As the COVID-19 pandemic continues into its third year, emerging data indicates increased risks associated with SARS-CoV-2 infection during pregnancy, including pre-eclampsia, intrauterine growth restriction, preterm birth, stillbirth, and risk of developmental defects in neonates. Here, we review clinical reports to date that address different COVID-19 pregnancy complications. We also document placental pathologies induced by SARS-CoV-2 infection, entry mechanisms in placental cells, and immune responses at the maternal-fetal interface. Since new variants of SARS-CoV-2 are emerging with characteristics of higher transmissibility and more effective immune escape strategies, we also briefly highlight the genomic and proteomic features of SARS-CoV-2 investigated to …

Sequencing Antisense Transcriptome Of Populus Through Antisense/Sense Transcript Pair Enrichment, Emma V. Burke

Dissertations, Master's Theses and Master's Reports

Past transcriptome research on plants focused primarily on protein coding genes, and only recently researchers began looking into the non-protein coding regions that may play significant roles in gene regulation. Antisense RNA transcripts that are found naturally in the cell share complementary sequence with sense transcripts and have been shown to regulate expression of their sense counterparts. Since antisense RNA has been largely under-studied and difficult to sequence because of their low relative abundance, new methods are needed to target antisense RNA for efficient genome-wide profiling. To address this gap in methods to efficiently and cost effectively enrich antisense RNA …

Changes In Poplar Digestibility Due To Overexpression Of Laccase Genes, Fnu Arunima

Dissertations, Master's Theses and Master's Reports

Woody biomass, particularly poplar, is a sought-after feedstock for lignocellulosic biofuels because of its year-round availability and high productivity. Because of cell wall components like lignin, poplar is inherently resistant to enzymatic saccharification. The experiment aims to determine whether the controlled overexpression of laccase genes alters the biomass composition and whether it can create poplar that is more digestible than the wildtype.

Three sets of transgenic poplar (Populus tremula x alba) samples were evaluated: laccase 18, laccase 27, and STTM. Laccase 18 samples, an target of miRNA397a was overexpressed along with Laccase 27. Short Tandem target Mimic (STTM) technology …

Study Of Nanocomposite Materials Using Molecular Dynamics, Prashik Sunil Gaikwad

Dissertations, Master's Theses and Master's Reports

There is an increase in demand for new lightweight structural materials in the aerospace industry for more efficient and affordable human space travel. Polymer matrix composites (PMCs) with reinforcement material as carbon nanotubes (CNTs) have shown exceptional increase in the mechanical properties. Flattened carbon nanotubes (flCNTs) are a primary component of many carbon nanotube (CNT) yarn and sheet materials, which are promising reinforcements for the next generation of ultra-strong composites for aerospace applications. These flCNT/polymer materials are subjected to extreme pressure and temperature during curing process. Therefore there is a need to investigate the evolution of properties during the curing …

Comprehensive Analysis Of Seismic Signals From Pacaya Volcano Using Deep Learning Event Detection, Jessica L. Devlieg

Dissertations, Master's Theses and Master's Reports

Pacaya volcano located 30 km SW of Guatemala City, Guatemala, has been erupting intermittently since 1961. Monitoring of seismicity is crucial to understanding current activity levels within Pacaya. Traditional methods of picking these small earthquakes in this noisy environment are imprecise. Pacaya produces many small events that can easily blend in with the background noise. A possible solution for this problem is a machine learning program to pick first arrivals for these earthquakes. We tested a deep learning algorithm (Mousavi et al., 2020) for fast and reliable seismic signal detection within a volcanic system. Data from multiple deployments were used, …

Treating Contaminated Water: Predicting Reactivities Of Aqueous Organic Contaminants With Hydrated Electrons, And Development Of A Biogarden To Manage Greywater Discharge In Monteverde, Costa Rica, Rose C. Daily

Dissertations, Master's Theses and Master's Reports

Advanced reduction processes (ARPs) that generate highly reactive solvated electrons (e^-_aq) are a promising method for the destruction of conventional and emerging aqueous organic contaminants. While there is a large database of contaminant reactivity with e^-_aq in the literature, there is little information on the detailed elementary mechanisms for reduction of multifunctional group compounds and the impact of those functional groups on reactivity. As it is difficult to determine specific mechanisms through experiments and time consuming to measure reactivity, the development of computational approaches to elucidate mechanisms and predict reactivity is becoming increasingly important. In …

Machine Learning And Deep Learning Approaches For Gene Regulatory Network Inference In Plant Species, Sai Teja Mummadi

Dissertations, Master's Theses and Master's Reports

The construction of gene regulatory networks (GRNs) is vital for understanding the regulation of metabolic pathways, biological processes, and complex traits during plant growth and responses to environmental cues and stresses. The increasing availability of public databases has facilitated the development of numerous methods for inferring gene regulatory relationships between transcription factors and their targets. However, there is limited research on supervised learning techniques that utilize available regulatory relationships of plant species in public databases.

This study investigates the potential of machine learning (ML), deep learning (DL), and hybrid approaches for constructing GRNs in plant species, specifically Arabidopsis thaliana, …

Rain-Induced Hazards In Remote, Low-Resource Communities: A Case Study Of Flash Flooding In The Usulután Department, El Salvador, Natalea Cohen

Dissertations, Master's Theses and Master's Reports

Rain-induced natural hazards can lead to devastating and potentially life-threatening impacts. Understanding areas susceptible to flash flooding and characterizing the intensity of flash flood events is critical in improving the mitigation and emergency preparedness of vulnerable communities. Flash floods occur on small spatial scales and for short durations making it challenging to classify flash flood susceptibility and forecast events. Modeling flash flooding becomes even more difficult when focusing on data-poor regions. This study is based in California, El Salvador, an agricultural community located in the Central American Dry Corridor (CADC), a region experiencing the impacts of climate change and associated …

Collagen V Promotes Fibroblast Contractility, And Adhesion Formation, And Stability, Shaina P. Royer-Weeden

Dissertations, Master's Theses and Master's Reports

Ehlers-Danlos syndrome, classical type, (cEDS) is a hereditary connective tissue disorder causing excessive elasticity and fragility of the connective tissue and problems with wound healing. Most cases of cEDS are caused by haploinsufficiency for collagen V. Collagen V regulates collagen fibril diameter. In cEDS fibroblast migration is impaired and integrin expression is altered.

The effects of collagen V on collagen gel ultrastructure and how it alters its mechanical properties were measured using scanning electron microscopy (SEM) and rheology respectively. Fibroblast contractility and adhesion dynamics were investigated to better understand the role of fibroblast disfunction in wound healing in cEDS. To …

Has Bollywood Lost The Plot? Analyzing The Influence Of Item Songs On Rape Culture In India, Donna Susan Mathew

Dissertations, Master's Theses and Master's Reports

An item song is a provocative musical song and dance sequence that appears in Bollywood films that have little to no connection to the film’s plot, performed by an item girl for the male gaze. Contemporary Bollywood item songs have become highly contested social and political texts in the discourse surrounding rape culture in India. This research explores the socio-cultural context of rape culture in India and examines what makes item songs a popular and acceptable form of entertainment in a patriarchal, conservative society where sexualized violence against women is a major cause for concern.

The study also addresses the …

Wavelet-Based Real-Time Harmonic Phasor Estimation In Complex Signals With Inter-Harmonics And Transient Events, M A Aziz Jahan

Dissertations, Master's Theses and Master's Reports

Addressing the evolving challenges in modern power systems induced by the integration of Inverter Based Resources (IBRs), such as solar inverters, wind turbine converters, electric vehicle charging stations etc is the main goal of this research. The study focuses on the critical task of harmonic phasor estimation in the presence of sub-harmonics, inter-harmonics, time-varying harmonics, DC offset, transient events, and other power quality disturbances. A novel wavelet-based harmonic phasor estimation method is proposed to enhance accuracy, particularly during transient events, ensuring a nuanced understanding of phase angle variations. The research emphasizes the versatility of wavelet analysis for both steady-state and …

White-Tailed Deer In A Winter-Wonderland: Long-Term Deer Yard Use And Methodological Considerations For Ungulate Fecal Dna Metabarcoding, Melanie A. Ottino

Dissertations, Master's Theses and Master's Reports

Northern white-tailed deer (Odocoileus virginianus) mitigate the increased energetic costs of severe winter conditions through obligate migration to densely congregated areas with abundant conifer cover, a behavior referred to as yarding. “Deer yards” in the Western Upper Peninsula (UP) of Michigan are principally located within the reduced snowpack and increased ambient temperature microclimates of densely canopied eastern hemlock (Tsuga canadensis) stands, but specific drivers of long-term site fidelity and utilization are largely uncharacterized. As an important game species of high economic and cultural value and a keystone herbivore with critical impact of plant community composition and structure, identifying winter yarding …

Effects Of Aging On Urinary Tract Epithelial Homeostasis And Immunity, Marianne M Ligon, Chetanchandra S Joshi, Bisiayo E Fashemi, Arnold M Salazar, Indira U Mysorekar

Faculty, Staff and Students Publications

A global increase in older individuals creates an increasing demand to understand numerous healthcare challenges related to aging. This population is subject to changes in tissue physiology and the immune response network. Older individuals are particularly susceptible to infectious diseases, with one of the most common being urinary tract infections (UTIs). Postmenopausal and older women have the highest risk of recurrent UTIs (rUTIs); however, why rUTIs become more frequent after menopause and during old age is incompletely understood. This increased susceptibility and severity among older individuals may involve functional changes to the immune system with age. Aging also has substantial …

Design And Implementation Of A Graphql Mesh Gateway: Federating Api Endpoints Based On A Defined Data Model, Marcus D. Scese

Dissertations, Master's Theses and Master's Reports

This paper introduces the GraphQL Mesh federated API (Application Programming Interface) gateway project, a comprehensive initiative implemented using GraphQL Mesh to solve data related issues within the USW-DSS (Undersea Warfare - Decision Support System). The project contributes to the evolving discourse on the pivotal role of Data Fabrics and Data Meshes in dismantling the barriers imposed by digital data silos. The project is a collaboration between researchers at Michigan Technological University, and engineers at ARiA (Applied Research in Acoustics LLC). The aim of the project is to resolve difficulties in understanding a large collection of API endpoints. By navigating the …

Engaging Patients In Antimicrobial Stewardship: Co-Designed Educational Tool To Improve Periprocedural Care Through De-Implementation Of Guideline-Discordant Antimicrobial Use, Hawra Al Lawati, Marlena Shin, Rebecca Lamkin, Tyler Thompson, Isabella Epshtein, Hillary Mull, Dipandita Basnet Thapa, Dimitri Drekonja, Maria C Rodriguez-Barradas, Teena Huan Xu, Howard Gold, A Rani Elwy, Judy Strymish, Westyn Branch-Elliman

Faculty, Staff and Students Publications

Effective de-implementation models often include replacement of an ineffective practice with an alternative. We co-developed patient education materials as a replacement strategy for inappropriate post-procedural antibiotics in cardiac device procedures. Lessons learned and developed materials may be used to promote infection prevention in other periprocedural settings.

Combining Charlson Comorbidity And Vacs Indices Improves Prognostic Accuracy For All-Cause Mortality For Patients With And Without Hiv In The Veterans Health Administration, Kathleen A Mcginnis, Amy C Justice, Vincent C Marconi, Maria C Rodriguez-Barradas, Ronald G Hauser, Krisann K Oursler, Sheldon T Brown, Kendall J Bryant, Janet P Tate, Veterans Aging Cohort Study Affiliations

Faculty, Staff and Students Publications

INTRODUCTION: As people age with HIV (PWH), many comorbid diseases are more common than among age matched comparators without HIV (PWoH). While the Veterans Aging Cohort (VACS) Index 2.0 accurately predicts mortality in PWH using age and clinical biomarkers, the only included comorbidity is hepatitis C. We asked whether adding comorbid disease groupings from the Charlson Comorbidity Index (CCI) improves the accuracy of VACS Index.

METHODS: To maximize our ability to model mortality among older age groups, we began with PWoH in Veterans Health Administration (VA) from 2007-2017, divided into development and validation samples. Baseline predictors included age, and components …

Knowledge Discovery On The Integrative Analysis Of Electrical And Mechanical Dyssynchrony To Improve Cardiac Resynchronization Therapy, Zhuo He

Dissertations, Master's Theses and Master's Reports

Cardiac resynchronization therapy (CRT) is a standard method of treating heart failure by coordinating the function of the left and right ventricles. However, up to 40% of CRT recipients do not experience clinical symptoms or cardiac function improvements. The main reasons for CRT non-response include: (1) suboptimal patient selection based on electrical dyssynchrony measured by electrocardiogram (ECG) in current guidelines; (2) mechanical dyssynchrony has been shown to be effective but has not been fully explored; and (3) inappropriate placement of the CRT left ventricular (LV) lead in a significant number of patients.

In terms of mechanical dyssynchrony, we utilize an …

Advancing Vehicular Communication Systems: An Evolution From Dsrc To 5g Nr C-V2x Technology For Enhanced Safety, Reliability, And Efficiency In Intelligent Transportation Systems, Mehnaz Tabassum

Dissertations, Master's Theses and Master's Reports

This work focuses on the evolution of connected vehicles communication technologies and performance evaluation of vehicular communication systems, specifically in the context of Cellular Vehicle-to-Everything (C-V2X) technology and the Third Generation Partnership Project (3GPP) specifications. The dissertation also discusses the evolution of vehicle communication systems from Dedicated Short-Range Communication (DSRC) through 5G technologies. It examines the motivation for this shift, which are the growing demand for transportation safety, low latency, high data rate, low energy use, and seamless inter connectivity. The research delves into the greater capabilities and improved performance that 5G offers for direct V2V communications by analyzing the …

Development And Verification Of Automated Fixtures For Functional Testing Of Space Grade Printed Circuit Board Assemblies, Nicholas A. Wylie

Dissertations, Master's Theses and Master's Reports

Orbion Space Technology is a developer and manufacturer of electric propulsion systems for military and commercial spacecraft. Orbion’s products include a Power Processing Unit (PPU) which is utilized for power and control of the satellite propulsion system. These PPUs are complex electro-mechanical assemblies that include multiple Printed Circuit Board Assemblies (PCBA) and are built to IPC standards. To ensure smooth fabrication and to reduce the risk of complications from in-process rework of PCBAs, comprehensive electrical functional testing at the board-level is required before higher- level assembly. Electrical functional testing provides verification of quality, workmanship, and manufacturing defects of the PCBAs. …

Clinical Approach To Evaluation Of Underlying Cardiac Device Infection In Patients Hospitalized With Bacteremia, Dierdre B Axell-House, Sarwat Khalil, M Rizwan Sohail

Faculty, Staff and Students Publications

More than 400,000 cardiac implantable electronic devices (CIEDs), including permanent pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy devices, are implanted every year in the United States (US). Infection is a serious complication of CIED therapy and is associated with high morbidity and mortality. While CIED pocket infection can be diagnosed based on clinical exam findings, positive blood culture may be the only manifestation of CIED lead infection. Thus, management of bacteremia in patients living with CIEDs requires special consideration. This review summarizes contemporary data in the context of the recently updated 2023 Duke-International Society for Cardiovascular Infectious Diseases Criteria for …

On The Gaussian-Core Vortex Lattice Model For The Analysis Of Wind Farm Flow Dynamics, Apurva Baruah

Dissertations, Master's Theses and Master's Reports

Wind power science has seen tremendous development and growth over the last 40 years. Advancements in design, manufacturing, installation, and operation of wind turbines have enabled the commercial deployment of wind power generation systems. These have been due, in a large part, to the expertise in the simulation and modeling of individual wind turbines. The new generation of wind energy systems calls for a need to accurately predict and model the entire wind farm, and not just individual turbines. The commercial deployment of these wind farms depends on model's ability to accurately capture the different physics involved, each at its …

Nanomaterials For Cardiovascular Engineering, Roya Bagheri

Dissertations, Master's Theses and Master's Reports

Cardiovascular diseases and disorders (i.e., those related to heart and blood vessels) are the main reasons for mortality worldwide. Nanomaterials, with their unique morphologies and properties, have a great potential for advancing cardiovascular engineering to treat diseases and disorders. In this dissertation, several cardiovascular applications of conductive nanomaterials were investigated. First, a conductive nanomaterial was explored to fabricate biohybrid nanomaterial-cardiomyocyte (CM – heart muscle cell) systems. Using Carbon Nanotube (CNT) forest as a 3D porous and conductive scaffold was investigated. The influence of the CNT forest on the viability, attachment, and spreading of CMs and their genetic information was …

Fabrication And Optical Properties Of Two-Dimensional Transition Metal Dichalcogenides, Manpreet Boora

Dissertations, Master's Theses and Master's Reports

Two-dimensional layered materials such as graphene and transition metal dichalcogenides have gained a lot of attention because of their distinctive chemical, optical, and electronic properties. Transition metal dichalcogenides can have a tunable bandgap in the range of 1 − 3 eV (visible), which enables their applications in ultrathin field effect transistors, photovoltaics, sensors, and optoelectronic devices. They exhibit an indirect-to-direct band gap transition when thinned down from bulk to a single layer. They show strong photoluminescence, electron–photon interaction, valley pseudospin, nonlinear optical response, and lack of dangling bonds. Many exotic phenomena appear when materials are thinned to nanoscale size because …

Development And Testing Of A Low Mass Vibratory Lunar Compactor, Charles Carey

Dissertations, Master's Theses and Master's Reports

NASA and other agencies are working to return to the moon, with the Artemis Program [1]. As a part of this new effort, an emphasis is being placed on having a sustained presence, building lunar bases and other permanent structures. The development of such infrastructure will require the development of civil engineering structures, and site preparation becomes a necessity. The Planetary Surface Technology Development Laboratory is developing a low mass lunar compactor as part of an autonomous site preparation vehicle in partnership with Colorado School of Mines, funded by NASA’s 2021 Lunar Surface Technology Research grant. The low mass lunar …

Real-World Experience With Cefiderocol Therapy For Pseudomonas Aeruginosa And Other Multidrug Resistant Gram-Negative Infections Within The Veterans Health Administration, 2019–2022, Andrew Chou, David Ramsey, Eva Amenta, Barbara W Trautner

Faculty, Staff and Students Publications

OBJECTIVE: Single-center and regional studies have reported outcomes after treatment with cefiderocol, a novel siderophore cephalosporin. We report on real-world use, clinical outcomes, and microbiological outcomes with cefiderocol therapy within the Veterans' Health Administration (VHA).

DESIGN: Prospective, observational descriptive study.

SETTING: Veterans' Health Administration, 132 sites across the United States, during 2019-2022.

PATIENTS: This study included patients admitted to any VHA medical center who received cefiderocol for ≥2 days.

METHODS: Data were obtained from the VHA Corporate Data Warehouse and through manual chart review. We extracted clinical and microbiologic characteristics and outcomes.

RESULTS: In total, 8,763,652 patients received 1,142,940,842 prescriptions …

Bacteriuria In Older Adults Triggers Confusion In Healthcare Providers: A Mindful Pause To Treat The Worry, Eva M Amenta, Robin L P Jump, Barbara W Trautner

Faculty, Staff and Students Publications

The evidence base for refraining from screening for or treating asymptomatic bacteriuria (ASB) in older adults is strong, but both practices remain prevalent. Clinical confusion over how to respond to a change from baseline, when to order a urinalysis and urine culture, and what to do with a positive urine culture fuels unnecessary antibiotic use for ASB. If the provider can take a mindful pause to apply evidenced-based assessment tools, the resulting increased clarity in how to manage the situation can reduce overtreatment of ASB.

Physical, Optical, And Chemical Properties Of Light Absorbing Aerosols And Their Climatic Impacts, Susan Mathai

Dissertations, Master's Theses and Master's Reports

Aerosols are particles suspended in the atmosphere; they are emitted during natural phenomena such as dust storms, wildfires, and volcanic eruptions, and during anthropogenic activities like household wood burning, vehicles operations, and industrial productions, or they can form in the atmosphere from gas to particle partition. Aerosols impact earth’s weather and climate by absorbing and scattering the incoming solar and the outgoing earth thermal radiation and interacting with clouds. The optical properties of aerosols evolve as the chemical and physical properties vary during their residence in the atmosphere. In addition, the aerosols’ properties strongly depend on the vertical distribution in …