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Effect Of Electron Demand On Sensing Behavior Of Carbazolopyridinophanes, Grace Abban

Theses and Dissertations

Hydrazine (HZ), monomethylhydrazine (MMH), and 1,1-dimethylhydrazine (UDMH) are widely used as high energy rocket propellants in bipropellant rocket engines. However, hydrazine and its derivatives are highly flammable and carcinogenic. Currently, hydrazine sensors used for detection are irreversible which makes them costly. Two proposed carbazolopyridinophanes containing intramolecular hydrogen bonds were synthesized to detect hydrazine as real-time reversible sensors. However, their thresholds for detection (100 and 25 ppb for CPand 22OMeCPrespectively) were above the regulatory limit of 10 ppbdue to background fluorescence. It was established that the quenching of carbazole in the presence of the CP system has a direct correlation to …

Mechanical And Material Properties Of Nitinol And Its Application To Stents, Ariana Solis Eichler

Theses and Dissertations

Nitinol is a functional material with superelastic and shape memory properties derived from its unique molecular structure. The purpose of this thesis is to explore how the material and mechanical properties of self-expanding Nitinol stents affects the forces applied to arterial walls during stent deployment compared to the traditional balloon-expanding stainless steel stents, in addition to contrasting thin and thick-walled pressure vessel mathematical models. Nitinol’s mechanical properties can be optimized for stent applications by tailoring its processing procedures. Nitinol stents demonstrated a reduced circumferential hoop stress on the vessel wall and greater factor of safety with respect to vessel rupture …

Using Disruptive Coloration And Ultraviolet Light To Prevent Barnacle Settlement, Kailey Nicole Richard

Theses and Dissertations

Biofouling or the accumulation of unwanted micro and macro organisms is problematic for the shipping industry. Barnacles are one of the most abundant fouling organisms and their settlement on ship hulls can result in costly damage. Several methods have been developed to prevent the formation of biofouling, including antifouling coatings and mechanical techniques, but the search for more effective and environmentally friendly solutions is still ongoing. This thesis investigated two methods aimed at barnacle prevention: color patterning and the application of ultraviolet light. The first method utilized disruptive coloration, a common mechanism observed in nature by terrestrial organisms (i.e. butterflies) …

Organic Sediment Impacts On Seagrasses And Their Associations With Benthic Fauna, Sean Matthew Crowley

Theses and Dissertations

Human-population growth and rapid rates of urbanization have led to eutrophic conditions in estuaries throughout the world. Effects often include severe algal blooms, decreased dissolved oxygen levels, and the accumulation of fine-grained organic-rich sediments. One frequent negative consequence of eutrophication is the decline of seagrasses, a vital component of coastal ecosystems. Seagrasses provide shelter from predation, serve as nursery habitat, stabilize sediments, act as a sink for excess carbon, produce oxygen, and are a food source for many herbivores. Seagrasses are also sensitive to environmental changes, such as declining water quality and increased sedimentation rates. This study examines the impacts …

Multiple Cold Tolerance Trait Phenotyping Reveals Shared Quantitative Trait Loci In Oryza Sativa, Naoki Shimoyama, Melineeh Johnson, André Beaumont, Michael Schläppi

Biological Sciences Faculty Research and Publications

Background

Developing chilling tolerant accessions of domesticated Asian rice is a potential source of significant crop improvement. The uniquely chilling sensitive nature of the tropically originating Oryza sativa make it the most important cereal crop that can gain significantly from improved tolerance to low temperatures. However, mechanisms underlying this complex trait are not fully understood. Oryza sativa has two subspecies with different levels of chilling tolerance, JAPONICA and INDICA, providing an ideal tool to investigate mechanistic differences in the chilling stress tolerance responses within this important crop species.

Results

The Rice Diversity Panel 1 (RDP1) was used to investigate …

Versatile Catalytic Processes By Metal Oxide Nanomaterials With Tunable Porosity, Shanka Dissanayake

Doctoral Dissertations

Research on novel highly active mesoporous metal oxides by an inverse micelle method dubbed University of Connecticut (UCT) materials for versatile catalytic reactions is reported. The first section discusses the synthesis of highly active mesoporous cobalt oxide for the elimination of 2-propanol. The superior activity is correlated to better low temperature reducibility, large pore volumes, higher Co3+/Co2+ ratios, and higher number of surface-active oxygen species. Reaction forms carbonyl and carbonate species on the surface of the catalysts before complete oxidation. The second section is devoted to the synthesis of high surface area cerium oxide and zirconium oxide catalysts for self-condensation …

Numerical Simulation Of Low Reynolds Number Locomotion In Viscoelastic Media, Nesreen Abdulrahim Althobaiti

Theses and Dissertations

We use computational models to investigate 2D swimmers within various fluid media with low Reynolds Number. Extensions of the standard Immersed Boundary (IB) Method are proposed so that the fluid media may satisfy no slip, partial slip or free-slip conditions on the moving boundary. The fluid equations are solved through a Multigrid preconditioned GMRES solver. Our numerical results indicate that slip may lead to substantial speed enhancement for swimmers in a viscoelastic fluid, as well as in a viscoelastic two-fluid mixture. Under the slip conditions, the speed of locomotion is dependent in a nontrivial way on both the viscosity and …

The Origin Of Usurpation And Tyranny: Nonagentic Anti-Imperialism Of The Twenty-First Century And The Legacy Of Chavismo, Juan Bustillo

International Studies (MA) Theses

As Venezuela’s Chavista regime presides over the country’s descent into Latin America’s worst refugee and humanitarian crisis in modern times, a mass exodus of nearly five million Venezuelans since 2015, the rhetoric of Western anti-imperialists and the regime itself has absolved it of any responsibility for the crisis and the increasing authoritarianism that led to it by abdicating the regime's agency to act according to its own free will. This paper develops the discursive concept of nonagentic anti-imperialism, a rhetoric that effectively absolves self-declared anti-imperialist regimes, from Castro’s Cuba to Rajapaksa’s Sri Lanka, of human rights abuses and democratic erosions …

Reproductive Health In The Philippines: Poverty, Religiosity, And Navigating Reproductive Choices, Allison Goncena

International Studies (MA) Theses

This dissertation centers the Philippines as a case study in which quantitative and qualitative data from empirical studies, science journal articles, social science texts, and interviews are cross-examined to ascertain two main areas of interest. The first incentive is to identify and analyze the Catholic Church’s resources in perpetuating moral male-dominant rhetoric that have delayed efforts supporting reproductive health intended to aid low-income women concerning their sexual and reproductive health. The second incentive is to detect how low-income women’s thoughts and behaviors in making reproductive decisions are resonant or not of the Church’s moral rectitude over SRH through their demonstrations …

The Influence Of An Educational Intervention In Developing The Interprofessional Values And Behaviors Of Doctor Of Physical Therapy Students, Jennifer C. Fay

Education Doctoral

Interprofessional collaboration is a key component of the provision of high quality, safe, and effective healthcare. The complex needs of patients demand that healthcare professionals demonstrate competency within their particular discipline, and in interprofessional collaboration. The programs that educate healthcare professionals, including physical therapy programs, are obliged to provide students interprofessional education (IPE) to meet accreditation guidelines and to prepare students for professional practice. The literature lacks evidence on the ability of IPE to impact higher level learning outcomes, such as students’ interprofessional behaviors. The purpose of this study was to understand the influence of an IPE experience on Doctor …

The Investigation Of Group 1 Late Embryogenesis Abundant Protein 6 And Its Role In Arabidopsis Thaliana Desiccation Tolerance, Joann Eise Thomson

Masters Theses

Like most seeds, Arabidopsis thaliana seed development is divided into three major phases: morphogenesis, storage deposition, and maturation drying. During maturation drying the seed becomes desiccation tolerant (DT) at some point and the seed rapidly loses water until its moisture level is approximately 10% on a fresh weight basis. The ability of the seeds to withstand this extreme water loss is hypothesized to be due, in part, to the accumulation of late embryogenesis abundant (LEA) proteins. In A. thaliana, there are 51 LEA proteins which are divided into seven groups based on amino acid sequence similarities. Group 1 LEA …

Bloom Or Bust: Search For Phytoplankton Community Drivers Using Long-Term Time-Series Observations And Field Measurements In A Model Great Lakes Estuary, Jasmine Mancuso

Masters Theses

As sentinels of climate change and other anthropogenic effects, freshwater lakes are experiencing ecosystem disruptions at every level of the food web, beginning with the phytoplankton. One of the major threats to waterbodies around the world are cyanobacterial harmful algal blooms (HABs) resulting from anthropogenic eutrophication and exacerbated by climate change. Muskegon Lake, a drowned river mouth Great Lakes estuary on the east coast of Lake Michigan, is no exception and was declared an Area of Concern by the EPA in 1987 with nuisance algal blooms cited as a beneficial use impairment. Using long-term data and additional 2019 sampling, we …

Risk And Protective Factors For Psychological Distress Following A Morally Injurious Event In Combat Veterans, Aaron Keating

Dissertations

Morally injurious events have been shown to increase the likelihood of experiencing anxiety, depressive, and posttraumatic stress symptoms of combat veterans. Research has found that guilt and shame are associated with higher levels of symptomology following morally injurious events. Similarly, individuals who are high in trait proneness to guilt and shame may be at higher risk for developing symptoms following a morally injurious event; however, no research to date has examined this possibility. In addition, acts that go against what one considers morally right bring about cognitive dissonance which then leads to anxiety. In order to reduce anxiety caused by …

Characterization Of Treatment Planning System Photon Beam Modeling Errors In Iroc Houston Phantom Irradiations, Mallory Glenn

Dissertations and Theses (Open Access)

In radiation therapy, proper commissioning of the treatment planning system’s (TPS) dose calculation algorithm is critical because any errors in this process impact all treatment plans prepared in the system. Previously, TPS errors have been identified as a major cause for poor phantom irradiation performance, which may also mean that patients are treated suboptimally. The purpose of this work was to investigate the TPS beam modeling developed by the radiotherapy community to understand where inconsistencies may arise, which variables are most susceptible to variations, and in what way changing these variables can alter dose calculations.

Using the Imaging and Radiation …

Modulating Avidity Of H8f4-Car By Regulation Of Expression Via Codon Modification, Rolando Vedia

Dissertations and Theses (Open Access)

Despite recent advances in the field of cancer immunotherapy and chimeric antigen receptor (CAR) therapies for the treatment of acute myeloid leukemia (AML), there is a need for more unique and innovative modalities to improve these therapies. Our group has extensively studied and demonstrated the potential of targeting the leukemia-associated antigen PR1 in the setting of AML. PR1 is an HLA-A2-restricted nonameric peptide derived from serine proteases neutrophil elastase and proteinase 3, is overexpressed on myeloid leukemia cells, and expressed at normal low levels in healthy hematopoietic cells. We have demonstrated efficacy in targeting PR1/HLA-A2 via the novel development of …

Directed Evolution Of Macrocyclic Peptides For Inhibition Of Autophagy, Joshua Gray

Dissertations and Theses (Open Access)

In recent decades it has become increasingly clear that induction of autophagy plays an important role in the development of treatment resistance and dormancy in many cancer types. Chloroquine (CQ) and hydroxychloroquine (HCQ), two autophagy inhibitors in clinical trials, suffer from poor pharmacokinetics and high toxicity at therapeutic dosages. This has prompted intense interest in the development of targeted autophagy inhibitors to re-sensitize disease to treatment with minimal impact on normal tissue. We utilized Scanning Unnatural Protease Resistant (SUPR) mRNA display to develop macrocyclic peptides targeting the autophagy protein LC3. The resulting peptides bound LC3A and LC3B—two essential components of …

Investigating The Role Of Quaking In Antigen Uptake And Cross-Presentation By Dendritic Cells, Yating Li

Dissertations and Theses (Open Access)

Dendritic cells (DCs) are considered the most potent antigen presenting cells (APC) due to their superior capability of cross-presenting exogenous antigens to CD8⁺ T cell for strong adaptive immune responses. They internalize foreign antigens by phagocytosis, endocytosis or macropinocytosis, which are then processed in endosomal compartments and loaded onto MHC Class I molecules. However, the molecular mechanisms regulating exogenous antigen uptake and cross-presentation by DCs are not fully understood.

In this study, we discovered that an RNA-binding protein, Quaking (QKI) plays a pivotal role in antigen uptake by DCs. Our previous studies in neural stem cells and microglia have …

Active Magnetic Radiation Shielding For Long-Duration Human Spaceflight, Kristine Ferrone

Dissertations and Theses (Open Access)

Exploration of interplanetary space presents dramatic hazards to human survival.

Space radiation hazards outside the protection of the Earth’s magnetosphere can

produce both acute and chronic health risks and thus become limiting factors for

NASA’s planned mission to Mars by the 2030s. Radiation exposure on a Mars mission

is delivered primarily by high energy ions from galactic cosmic rays and moderate

energy protons from solar particle events. The chronic radiation dose due to galactic

cosmic rays on a typical Mars mission is on the order of 1 Sv, and additional acute

radiation dose from solar flares can reach over 4 …

Mutations Within And Between Early Cell Division Proteins And Their Effects On Division Regulation In Escherichia Coli, Kara Schoenemann

Dissertations and Theses (Open Access)

Cell division is a highly regulated process that must coordinate multiple implicit activities in different locations in the cell simultaneously. E. coli utilizes a macromolecular machine known as the divisome to accomplish cytokinesis. Assembly of the divisome begins with the assembly of a simpler structure known as the proto-ring. The proto-ring consists mainly of three essential proteins: FtsZ and its membrane tethers FtsA and ZipA. In this work, I aimed to understand the early regulation of division in E. coli by investigating the structure/function relationships of the proto-ring proteins, as well as their interactions with one another and how these …

Targeting Unique Domains Of Lsd1 Regulates Pediatric Glioma Innate Immunity And Nk Cell Metabolism, Cavan Bailey

Dissertations and Theses (Open Access)

Regulation of chromatin accessibility is a key mechanism of cellular identity, allowing different tissues to develop using the same DNA template. Cancers will often hijack these epigenetic pathways, reactivating developmental genes to drive growth and deactivating tumor suppressor and immune recognition genes. Chromatin-modifying proteins deposit and remove chemical moieties from histone tails to aid in governing gene expression, and these proteins have become a new therapeutic target in cancer. Traditional chemotherapeutics aim to damage DNA, dysregulate cell division, or block hormonal growth signals, but epigenetic therapy can target vulnerabilities specific to cancer cells and broadly change gene expression patterns that …

Elevated Cochlear Adenosine Causes Hearing Loss Via Adora2b Signaling, Jeanne Manalo

Dissertations and Theses (Open Access)

Over 538 million people in the world have been diagnosed with hearing loss (HL). Current treatments for the most common type of HL, sensorineural HL, are limited to hearing aids and cochlear implants with no FDA-drugs available. The hearing process demands an abundance of ATP and HL is often attributed to a disruption in this metabolic energy currency. Patients who lack adenosine deaminase (ADA), the enzyme that irreversibly metabolizes adenosine, have high levels of adenosine that yield severe health problems, including HL; however, the pathogenic mechanisms behind HL and adenosine remain elusive. Our lab has found a HL phenotype in …

Methods To Investigate Hyperthermia Induced By Tumor Treating Fields, Ruchi Singh

Dissertations and Theses (Open Access)

Tumor Treating Fields (TTFields) are an antineoplastic treatment delivered via application of alternating electric fields using insulated transducer arrays placed directly on the skin in the region surrounding the tumor. TTF’s is a non-invasive application of low-intensity (1-3 V/cm), intermediate-frequency (100-500 kHz) alternating electric fields. The predominant mechanism by which TTFields are thought to kill tumor cells is the disruption of mitosis through the depolymerization of microtubules and interruption of the spindle structure leading to mitotic catastrophe and the formation of non-viable daughter cells. Tumor Treating fields do not stimulate nerves and muscle because of their high frequency, and do …

Putative Roles Of Cd200 In The Leukemogenesis And Immune Evasion Of Leukemia Stem Cells, Shelley Herbrich

Dissertations and Theses (Open Access)

Acute myeloid leukemia (AML) stem cells (LSC) are capable of surviving current standard chemotherapy and are the likely source of deadly, relapsed disease. While stem cell transplant serves as proof-of-principle that AML LSCs can be eliminated by the immune system, the translation of existing immunotherapies to AML have been met with limited success. Consequently, understanding and exploiting the unique immune mechanisms of AML LSCs is critical. To identify novel immunotherapeutic targets, we sourced multiple large, publicly available datasets and identified CD200 as a potential stem-cell specific immune checkpoint in AML. We hypothesized that CD200 was a stem-cell specific mechanism of …

Histological And Functional Characterization Of Cervical Spinal Cord Injury After Graded Contusion, Chrystine Gallegos

Dissertations and Theses (Open Access)

Most spinal cord injuries (SCIs) are cervical contusions and result in deficits for both locomotion and reaching and grasping functions. Previous studies have characterized histological and functional deficits in locomotion using primarily thoracic contusions, but most patients have cervical injuries. Damage to descending long spinal tracts (dLSTs) is one well-established cause of functional loss after SCI and has been explored in laceration and transection models, but these are not clinically relevant. In this study, I will explore the histological and functional deficits after graded cervical hemicontusion SCI and examine the potential contribution of different histological deficits to forelimb function after …

Statistical Methods For Resolving Intratumor Heterogeneity With Single-Cell Dna Sequencing, Alexander Davis

Dissertations and Theses (Open Access)

Tumor cells have heterogeneous genotypes, which drives progression and treatment resistance. Such genetic intratumor heterogeneity plays a role in the process of clonal evolution that underlies tumor progression and treatment resistance. Single-cell DNA sequencing is a promising experimental method for studying intratumor heterogeneity, but brings unique statistical challenges in interpreting the resulting data. Researchers lack methods to determine whether sufficiently many cells have been sampled from a tumor. In addition, there are no proven computational methods for determining the ploidy of a cell, a necessary step in the determination of copy number. In this work, software for calculating probabilities from …

Experimental Characterization And Biological Assessments Of Polymeric Mesh Implants, Xinyue Lu

All Dissertations

In use since the 1960s, polypropylene (PP) biomaterials are common in commercially available hernia meshes due to their high tensile strength, good flexibility, and chemical resistance. The in vivo environment is highly variable, exposing mesh implants to oxidizing species and mechanical strains caused by normal healing, tissue integration, and the immediate and chronic inflammatory responses. As a result, changes in mesh implant materials can occur in vivo, including morphological changes, chemical changes and mechanical changes. The broad objective of this dissertation was to explore mechanisms of material changes in polymeric mesh implants after in vivo exposure using experimental characterization and …

Impact Of Biological Wastewater Treatment On The Reactivity Of N-Nitrosodimethylamine (Ndma) Precursors, Xiaolu Zhang

All Dissertations

N-Nitrosamines are a group of probable human carcinogens associated with 10-6 lifetime cancer risks at low ng/L levels in drinking water. N-nitrosamines can form via the reactions between chloramines (i.e., monochloramine, dichloramine) and organic precursors (e.g., secondary, tertiary and quaternary amines). Municipal wastewater effluents are considered one of the major sources of N-nitrosamine precursors that can impact downstream drinking water qualities. Although many studies have investigated the formation of N-nitrosamines in the influents and effluents of wastewater treatment plants (WWTPs), the major sources of N-nitrosamine precursors are still largely unknown. The first objective of this research was to evaluate the …

Building A Strategy For Key Energy Transitions: Modeling Biophysical Economics, John Sherwood

All Dissertations

Economists rarely model the economy as explicitly bound by Earth's ecological systems. However, ecological systems act as constraints on the economy --- constraints that have historically been too far away from economic productivity to seriously consider. These ecological or biophysical constraints have been growing closer and more prominent as natural resources are depleted and environmental impacts increase. Modeling these constraints is what defines the emerging sub-discipline of biophysical economics, BPE. The goal of this dissertation is to map out and extend current biophysical economics modeling strategies. BPE provides the ideal framework to holistically understand energy transitions towards sustainability.

In Chapter …

Diagnosis, Rupture Risk Evaluation And Therapeutic Intervention Of Abdominal Aortic Aneurysms Using Targeted Nanoparticles, Xiaoying Wang

All Dissertations

Abdominal aortic aneurysm (AAA) disease causes dilation of the aorta that can lead to aortic rupture and death if not treated early. It is the 14th leading cause of death in the U.S. and is cited as the 10th leading cause of death in men over age 55, affecting thousands of patients and their families. To date, AAA patients have minimal access to safe and efficient imaging modalities for diagnosis as well as pharmacotherapies. AAA is usually detected and monitored with ultrasonography or contrast-enhanced computed tomography (C.T.), which doesn’t provide biomechanical information of the AAAs that are essential for predicting …

Development Of Solid Sampling Modalities For The Liquid-Sampling Atmospheric Pressure Glow Discharge Microplasma, Htoo Paing

All Dissertations

Fast pretreatment of samples, low resource consumption, and high analytical throughput makes direct solid sampling techniques an attractive choice for a wide range of applications. Currently there are a plethora of analytical techniques capable of solid sampling. However, no commercial technique is available that is capable of taking advantage of the key concepts of solid samplings. General disadvantages amongst the current solid sampling instrumentation are high cost of operation, limited analyte choice, and reduced analytical performance. In that regard, it is important to develop a source that has low operation cost as well as the capability to analyze a diversity …