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Bottom-Up Lignomics: Towards The Development Of Adduct Electrospray Ionization Mass Spectrometric Methods To Characterize And Sequence Lignin Oligomers, Shardrack O. Asare

Theses and Dissertations--Chemistry

Lignin, the second most abundant naturally occurring polymer found in plant cell wall has the potential of becoming an alternative source for the production of chemical synthons for the pharmaceuticals and other chemical industries. While much gain has been made towards the development of degradation methods to break down lignin, effective analytical methods are still required to rapidly and accurately identify the products of lignin breakdown experiments. The goal of this work was to develop mass spectrometric methods for the characterization of lignin oligomers based on the study of model lignin compounds.

Unlike peptides and oligosaccharides, lignin model compounds that …

Studies Of Oxidative Damage, Brain Proteome, And Neurochemical Metabolites In Cognitive And Neurodegenerative Disorders: (1) Chemotherapy-Induced Cognitive Impairment; (2) Parkinson Disease Rat Model, Xiaojia Ren

Theses and Dissertations--Chemistry

The rate of cancer patients is increasing as the development of science and technology. Twenty million cancer survivors are estimated living in the United States by 2025. However, many cancer survivors show cognitive dysfunction, negatively affecting the quality of life. These cognitive impairments are recognized as chemotherapy-induced cognitive impairment (CICI), also called "chemo brain" by cancer survivors, including the diminished ability of memory and learning, hard to concentrate and focus, as well as diminution of executive function and processing speed. The etiologies and pathologies of CICI are complicated, especially in most cases the anti-cancer drug cannot cross the blood-brain barrier …

Synthesis And Characterization Of Carbonaceous Particles From Xylose And Soybean Residuals, Shanshan Wang

Theses and Dissertations--Chemistry

Carbonaceous materials, especially in micro and nanoscale, are useful in optical, energy storage, electronic, and biomedical devices or technologies. Techniques have been developed for preparation and modification of the carbonaceous materials, while it is still challenging to tailor the properties of carbonaceous materials effectively and economically. Laser is a powerful tool in academic and industrial laboratories, which also plays important roles in the preparation and modification of high-performance carbonaceous nanomaterials.

In this study low-cost hydrothermal synthesis, high-temperature annealing, and Laser ablation (LAL) methods are developed to prepare functionalized carbon nanomaterials and modify their electrochemical and optical properties.

Sub-micro hollow carbon …

Investigation Of Amyloid Β Oligomer Dissociation Mechanisms By Single Molecule Fluorescence Techniques, Hope Cook Abdalla

Theses and Dissertations--Chemistry

Alzheimer’s disease (AD) is currently considered the most prevalent neurodegenerative disease and places a large financial burden on society as healthcare resources are limited and the disease does not have a cure. Alzheimer’s disease is characterized by the presence of amyloid beta (Aβ) plaques and neurofibrillary tangles; however current literature suggests Aβ oligomers are the main aggregating species leading to AD symptoms. Therefore, the underlying cause of Alzheimer’s, accumulation of amyloid beta, is currently being studied in hopes of developing treatment options. Our research aims at determining the mechanism and kinetics of Aβ oligomer dissociation into non-toxic monomers in the …

Biomass-Derived Activated Carbons For Electrical Double Layer Supercapacitors: Performance And Stress Effect, Wenxin Cao

Theses and Dissertations--Chemical and Materials Engineering

The vigorous development of human civilization has significantly increased the energy consumption in recent years. There is a great need to use renewable energy sources to substitute the depleting traditional fossil fuels, such as crude oil, natural gas and coal. The development of low-cost and high-performance energy storage devices (ESDs) and systems have drawn great attention due to their feasibility as backup power supply and their applications in portable electronics and electric vehicles. Supercapacitors are among the most important ESDs because of their long charging-discharging cycle life, high power capability and a large operating temperature range. In this thesis, high-performance …

Towards The Rational Design And Application Of Polymers For Gene Therapy: Internalization And Intracellular Fate, Landon Alexander Mott

Theses and Dissertations--Chemical and Materials Engineering

Gene therapy is an approach for the treatment of acquired cancers, infectious disease, degenerative disease, and inherited genetic indications. Developments in the fields of immunotherapies and CRISPR/Cas9 genome editing are revitalizing the efforts to move gene therapy to the forefront of modern medicine. However, slow progress and poor clinical outcomes have plagued the field due to regulatory and safety concerns associated with the flagship delivery vector, the recombinant virus. Immunogenicity and poor transduction in certain cell types severely limits the utility of viruses as a delivery agent of nucleic acids. As a result, significant efforts are being made to develop …

Development Of Novel Temperature Responsive Polymeric Sorbents And Their Applications In Water Remediation, Shuo Tang

Theses and Dissertations--Chemical and Materials Engineering

Water remediation utilizing sorption has found strong interest due to its inexpensiveness, universal nature and ease of operation. In particular, thermo-responsive sorbents consisting of N-isopropylacrylamide (NIPAAm) offer significant potential as “smart” and advanced materials to remove multiple aqueous pollutants. NIPAAm exhibits excellent thermo-responsiveness, which senses the external temperature variation and changes its swelling and sorption behaviors in a sharp and rapid manner. At the beginning of this work, an extensive review of literature has been compiled to provide a summary of NIPAAm-based thermo-responsive sorbents in water/wastewater remediation applications.

Initially, we developed a novel approach to synthesize and characterize NIPAAm copolymeric …

Functionalization Of Iron Oxide Nanoparticles And The Impact On Surface Reactive Oxygen Species Generation For Potential Biomedical And Environmental Applications, Trang Mai

Theses and Dissertations--Chemical and Materials Engineering

Iron oxide nanoparticles (IONPs) have been widely studied for a variety of applications, from biomedical applications (e.g., cell separation, drug delivery, contrast agent for magnetic resonance imaging and magnetically mediated energy delivery for cancer treatment) to environmental remediations (e.g., heavy metal removal and organic pollutants degradation). It has been demonstrated that IONPs can induce the production of reactive oxygen species (ROS) via Fenton/Haber-Weiss reactions which has been shown to be one of the key underlying mechanisms of nanoparticles toxicity. This inherent toxicity of nanoparticles has been shown to enhance the efficacy of traditional cancer therapies such as chemotherapy and radiation. …

Cell Surface Coatings For Mammalian Cell-Based Therapeutic Delivery, Pei-Jung Wu

Theses and Dissertations--Chemical and Materials Engineering

The cell plasma membrane is an interactive interface playing an important role in regulating cell-to-cell, cell-to-tissue contact, and cell-to-environment responses. This environment-responsive phospholipid layer consisting of multiple dynamically balanced macromolecules, such as membrane proteins, carbohydrate and lipids, is regarded as a promising platform for various surface engineering strategies. Through different chemical modification routes, we are able to incorporate various artificial materials into the cell surface for biomedical applications in small molecule and cellular therapeutics.

In this dissertation, we establish two different cell coating techniques for applications of cell-mediated drug delivery and the localization of cell-based therapies to specific tissues. The …

Impact Of Conformational Change, Solvation Environment, And Post-Translational Modification On Desulfurization Enzyme 2'-Hydroxybiphenyl-2-Sulfinate Desulfinase (Dszb) Stability And Activity, Landon C. Mills

Theses and Dissertations--Chemical and Materials Engineering

Naturally occurring enzymatic pathways enable highly specific, rapid thiophenic sulfur cleavage occurring at ambient temperature and pressure, which may be harnessed for the desulfurization of petroleum-based fuel. One pathway found in bacteria is a four-step catabolic pathway (the 4S pathway) converting dibenzothiophene (DBT), a common crude oil contaminant, into 2-hydroxybiphenyl (HBP) without disrupting the carbon-carbon bonds. 2’-Hydroxybiphenyl-2-sulfinate desulfinase (DszB), the rate-limiting enzyme in the enzyme cascade, is capable of selectively cleaving carbon-sulfur bonds. Accordingly, understanding the molecular mechanisms of DszB activity may enable development of the cascade as industrial biotechnology. Based on crystallographic evidence, we hypothesized that DszB …

Targeted Illumination Strategies For Hydrogen Production From Purple Non-Sulfur Bacteria, John D. Craven

Theses and Dissertations--Chemical and Materials Engineering

The movement towards a more sustainable energy economy may require not only the generation of cleaner fuel sources, but the conversion of waste streams into value-added products. Phototrophic purple non-sulfur bacteria are capable of metabolizing VFAs (volatile fatty acids)and generate hydrogen as a byproduct of nitrogen fixation using energy absorbed from light. VFAs are easily produced from dark anaerobic fermentation of food, agricultural, and municipal wastes, which could then be fed into photobioreactors of purple bacteria for hydrogen production.

The process of photofermentation by purple bacteria for hydrogen production remains attractive due to the capability of reaching high substrate conversions …

Development Of Magnetic Nanocomposite Materials As Reusable Adsorbents For Chlorinated Organics In Contaminated Water, Angela Gutierrez

Theses and Dissertations--Chemical and Materials Engineering

The constant growth in population worldwide over the past decades continues to put forward the need to provide access to safe, clean water to meet human needs. There is a need for cost-effective technologies for water and wastewater treatment that can meet the global demands and the rigorous water quality standards and at the same maximizing pollutant efficiency removal. Current remediation technologies have failed in keeping up with these factors without becoming cost-prohibitive. Nanotechnology has recently been sought as a promising option to achieve these goals. The use of iron oxide magnetic nanoparticles as nanoadsorbents has led to a new …

Nanoharvesting And Delivery Of Bioactive Materials Using Engineered Silica Nanoparticles, Md Arif Khan

Theses and Dissertations--Chemical and Materials Engineering

Mesoporous silica nanoparticles (MSNPs) possess large surface areas and ample pore space that can be readily modified with specific functional groups for targeted binding of bioactive materials to be transported through cellular barriers. Engineered silica nanoparticles (ESNP) have been used extensively to deliver bio-active materials to target intracellular sites, including as non-viral vectors for nucleic acid (DNA/RNA) delivery such as for siRNA induced interference. The reverse process guided by the same principles is called “nanoharvesting”, where valuable biomolecules are carried out and separated from living and functioning organisms using nano-carriers. This dissertation focuses on ESNP design principles for both applications. …

The Fabrication And Characterization Of Metal Oxide Nanoparticles Employed In Environmental Toxicity And Polymeric Nanocomposite Applications, Matthew Logan Hancock

Theses and Dissertations--Chemical and Materials Engineering

Ceria (cerium oxide) nanomaterials, or nanoceria, have commercial catalysis and energy storage applications. The cerium atoms on the surface of nanoceria can store or release oxygen, cycling between Ce³⁺ and Ce⁴⁺, and can therefore act as a therapeutic to relieve oxidative stress within living systems. Nanoceria dissolution is present in acidic environments in vivo. In order to accurately define the fate of nanoceria in vivo, nanoceria dissolution or stabilization is observed in vitro using acidic aqueous environments.

Nanoceria stabilization is a known problem even during its synthesis; in fact, a carboxylic acid, citric acid, is …

Oleic Acid Vesicles: Formation, Mechanisms Of Reactivity, And Uses In Determination Of Terpene Activity, Laura A. Walther

Theses and Dissertations--Chemistry

This dissertation will focus on the volatile compounds released upon the burning of incense which are numerous and varied. The first part of this dissertation is the gas chromatography-mass spectral (GC-MS) analysis of burning incense collected via solid phase microextraction (SPME) with the aim of developing a library of compounds found in incense as used in the Orthodox church.

The second part of this dissertation has the aim of developing a method for forming oleic acid bilayer vesicle membranes and a fluorescence spectroscopy method by which the reactivities of these vesicles can be analyzed. These reactivities include permeability, fluidity, aggregation, …

Illuminating Dna Packaging In Sperm Chromatin: How Polycation Lengths, Underprotamination And Disulfide Linkages Alters Dna Condensation And Stability, Daniel Kirchhoff

Theses and Dissertations--Chemistry

During spermiogenesis, somatic chromatin is remodeled and a vast majority (> 90%) of DNA histones are replaced by short arginine-rich peptides called protamines. This compaction is immense, with protamine-DNA self-assembly in sperm chromatin resulting in a final volume roughly 1/6th of a somatic nucleus. This near crystalline organization of the DNA in sperm is thought crucial both for the transport of the paternal genes as well as for the protection of genetic information as sperm chromatin is transcriptionally inactive and all DNA repair mechanisms are shut down.

Chapter 1 will include an overview of the topics discussed in this document, …

Modeling The Condensed-Phase Behavior Of Π-Conjugated Polymers, Walker Mask

Theses and Dissertations--Chemistry

It is well established that the morphology and physical properties of an organic semiconducting (OSC) material regulate its electronic properties. However, structure-function relationships remain difficult to describe in polymer-based OSC, which are of particular interest due to their robust mechanical properties. If relationships among the molecular and bulk levels of structure can be found, they can aid in the design of improved materials. To explore and detail important structure-function relationships in polymer-based OSC, this work employs molecular dynamics (MD) simulations to study various π-conjugated polymers in different environments. Two independent investigations are discussed in this work. One investigation examines how …

Discovery Of Selective Probes Targeting Rna Polymerase I, Xiao Tan

Theses and Dissertations--Chemistry

RNR Polymerase I (RNA Pol I) is a “factory” that orchestrate the transcription of ribosomal rRNA for constructing ribosomes as a primary workshop for protein translation to sustain cell growth. Misregulation of RNA Pol I can cause uncontrolled cell proliferation, which leads to the development of cancer. Yeast (Saccharomyces cerevisiae) is a valuable model system to study RNA Pol I. Recently, the X-ray crystal structure of the yeast homologue of RNA Pol I was elucidated, offering the structural basis to selectively target this transcriptional machinery. The approach to selective RNA Pol I targeting was to disrupt the interaction …

Investigation Of Thiol-Containing Biomarkers And Their Role In The Exposome, Tracy Gastineau-Stevens

Theses and Dissertations--Chemistry

Exposomics is an emerging area of study that looks at how the environment around a person or persons affects their overall health. Biomarkers have emerged as useful tools to better understand how the exposome affects a person. In this work, we investigate two potential endogenous biomarkers, homocysteine and glutathione that have been previously implicated in a number of diseases that have been linked to environmental causes. We also investigated an environmental exposure, the fungicide Ziram, which epidemiologically has been linked to diseases. In our investigation, we utilized capillary electrophoresis and capillary electrophoresis-mass spectrometry to develop a method for homocysteine and …

Multi-Scale Computational Studies Of Calcium (Ca2+) Signaling, Bin Sun

Theses and Dissertations--Chemistry

Ca²⁺ is an important messenger that affects almost all cellular processes. Ca²⁺ signaling involves events that happen at various time-scales such as Ca²⁺ diffusion, trans-membrane Ca²⁺ transport and Ca²⁺-mediated protein-protein interactions. In this work, we utilized multi-scale computational methods to quantitatively characterize Ca²⁺ diffusion efficiency, Ca²⁺ binding thermodynamics and molecular bases of Ca²⁺-dependent protein-protein interaction. Specifically, we studied 1) the electrokinetic transport of Ca²⁺ in confined sub-µm geometry with complicated surfacial properties. We characterized the effective diffusion constant of Ca²⁺ in a cell-like environment, which helps to understand …

Empirical Assessment Of Callous-Unemotional Traits In Preschool: A Comparison Of Confirmatory Factor Analysis And Network Analysis, Pevitr Singh Bansal

Theses and Dissertations--Psychology

Callous – unemotional (CU) traits are a key factor in understanding the persistence and severity of conduct problems. The factor structure of CU traits has been primarily examined through confirmatory factor analysis (CFA) in childhood and adolescent samples, yet little research has examined the structure of CU traits in preschool. Further, current CFA models have yielded poor – to – marginally acceptable fit, suggesting the need for a more nuanced approach in understanding the structure of CU traits in early childhood using an interitem approach (i.e., network analysis). Within a sample of 109 preschool children (M age = 4.77, …

The Effect Of Posttraumatic Stress And Trauma-Focused Disclosure On Experimental Pain Sensitivity Among Trauma-Exposed Women, Caitlyn Olivia Hood

Theses and Dissertations--Psychology

Previous studies evaluating the impact of trauma history and PTSD on pain sensitivity yield inconsistent findings; the presence of trauma-related negative affective states may account for these discrepancies. Therefore, the proposed study aimed to evaluate the effect of trauma-related negative affect and PTSD symptoms on sensory and affective components of pain sensitivity among trauma-exposed women. Adult women (N = 87) with low and high PTSD symptoms underwent an emotional disclosure paradigm, during which they wrote about a traumatic event or a neutral topic. Participants then completed a pain induction procedure. Compared to women with low PTSD symptoms, women with …

Examining The Utility Of Behavioral Economic Demand In Addiction Science, Justin Charles Strickland

Theses and Dissertations--Psychology

The marriage of perspectives from behavioral economic theory and learning theory has the potential to advance an understanding of substance use and substance use disorder. Behavioral economic demand is a central concept to this interdisciplinary approach. Evaluating demand in the laboratory and clinic can improve previous research on the relative reinforcing effects of drugs by accounting for the multi-dimensional nature of reinforcement rather than viewing reinforcement as a unitary construct. Recent advances in the commodity purchase task methodology have further simplified the measurement of demand values in human participants. This dissertation project presents a programmatic series of studies designed to …

Cognition, Repetitive Thought, And Systemic Inflammation In The Midlife In The United States Study, Elana M. Gloger

Theses and Dissertations--Psychology

Segerstrom et al. (2017) found that more repetitive thought (RT) was related to lower interleukin-6 (IL-6), in older adults at average IQ. This study aimed to replicate and extend this finding in midlife adults, with a daily measure of RT, and additional inflammatory biomarkers. 153 participants were drawn from the Midlife in the United States (MIDUS) Refresher project; ages 25-70 (M = 45.07, SD = 10.96), 50.3% female, and 83% Caucasian. Cognition was assessed via the Brief Test of Adult Cognition by Telephone, biological data via fasted blood draw, and RT data were collected as part of the National …

When And Why We Protect Our Honor, Brian Michael Enjaian

Theses and Dissertations--Psychology

Men from a culture of honor often use physical aggression in response to threats as a way of restoring lost honor. Threats can range from being called an offensive name to someone flirting with their romantic partner. On the other hand, women from a culture of honor are expected to be submissive and avoid situations that can result in harm to their reputation. However, a recent meta-analytic review of the literature suggests that women do not always avoid situations that can harm their reputation. Rather, women in a culture of honor also use physical aggression in response to threats. In …

Posttraumatic Stress And Risky Sex In Trauma-Exposed College Students: The Role Of Personality Dispositions Toward Impulsive Behavior, Jessica Flores

Theses and Dissertations--Psychology

Posttraumatic stress disorder (PTSD) has been linked to heightened engagement in risky sexual behavior (RSB) across diverse samples, and impulsivity has been postulated as a potential linkage (Weiss et al., 2012). Limited information has been published on the role that impulsivity can play in strengthening the relationship between PTSD and RSB in college students. The current study examined the moderating role of impulsivity dispositions: negative/positive urgency, (lack of) perseverance, sensation seeking, and (lack of) premeditation on the association between PTSD symptoms and past-year RSB among a sample of 221 undergraduate students (77.4% female) with at least one DSM-5 defined traumatic …

Do Bulimic Behaviors Increase Shame? Toward An Understanding Of Transdiagnostic Risk, Heather A. Davis

Theses and Dissertations--Psychology

Binge eating is a harmful, maladaptive behavior associated with comorbid psychopathology. Theory posits that increases in maladaptive, transdiagnostic emotions following binge eating in individuals with BN may predict the experience of comorbid symptoms. The current study served as a laboratory test of the first part of this theory: whether state increases in maladaptive emotions occur following engagement in binge eating behavior in women with BN compared with healthy controls. Women (n = 51) were recruited from the community if they met DSM-5 criteria for BN or OSFED BN (of low frequency) (n = 21) or were free of lifetime disordered …

Neurobehavioral Measurements Of Natural And Opioid Reward Value, Aaron Paul Smith

Theses and Dissertations--Psychology

In the last decade, (non)prescription opioid abuse, opioid use disorder (OUD) diagnoses, and opioid-related overdoses have risen and represent a significant public health concern. One method of understanding OUD is as a disorder of choice that requires choosing opioid rewards at the expense of other nondrug rewards. The characterization of OUD as a disorder of choice is important as it implicates decision- making processes as therapeutic targets, such as the valuation of opioid rewards. However, reward-value measurement and interpretation are traditionally different in substance abuse research compared to related fields such as economics, animal behavior, and neuroeconomics and may be …

Measuring Glutamate And Oxygen In Brain Reward Circuits In Animal Models Of Cocaine Abuse And Decision-Making, Seth Richard Batten

Theses and Dissertations--Psychology

Drug-specific reward and associated effects on neural signaling are often studied between subjects, where one group self-administers drug and a separate group self-administers a natural reinforcer. However, exposure to drugs of abuse can cause long-term neural adaptations that can affect how an organism responds to drug reward, natural reward, and their reward-associated stimuli. Thus, to isolate drug-specific effects it is important to use models that expose the same organism to all of the aforementioned. Multiple schedules provide a means of dissociating the rewarding effects of a drug from the rewarding effects of food within a single animal. Further, drug users …

Development Of A Translational Model Of Co-Use Of Alcohol And Nicotine For Testing Potential Pharmacotherapies, Sarah Elizabeth Maggio

Theses and Dissertations--Psychology

Co-users of alcohol and nicotine are the largest group of polysubstance users worldwide. Although pharmacotherapies are available for alcohol (EtOH) or tobacco use disorders individually, it may be possible to develop a single pharmacotherapy to treat heavy drinking tobacco smokers through capitalizing on the commonalities in their mechanisms of action. Towards this goal, several models of concurrent access to EtOH and nicotine were explored as potential preclinical models of co-use using female alcohol-preferring (P) rats. Additionally, potential pharmacotherapeutics for the treatment of EtOH and nicotine co-use disorder were tested using different variations of our model. Treatments tested included (1) varenicline, …