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Electrochemical Performance Of Biomass-Derived Activated Carbon Supercapacitor Under Compression, Yulin Zhang

Theses and Dissertations--Chemical and Materials Engineering

Supercapacitors are important energy storage device of high-power density, fast charge/discharge rate, environmental friendliness and long service life. Currently, flexible supercapacitors have attracted widespread interest in academia and industry. Supercapacitors under the action of external force will inevitably cause structural changes, performance degradation and even loss of energy storage and supply functionalities. As the most abundant renewable resource so far, biomass is an important energy source for human survival and development. Most electrode materials for supercapacitors are porous activated carbons, which can be derived from abundant renewable biomass, contributing to the sustainable development of society and environmental protection. This thesis …

Interactions Of Lignin Dimers With Engineered Surfaces And Model Cell Membranes For Design Of Lignin-Based Materials, Mahsa Moradipour

Theses and Dissertations--Chemical and Materials Engineering

Capitalizing on byproducts of industrial and agricultural economies is among the utmost goals of sustainability. Of particular interest for commercial upgrading is lignin, a phenolic biopolymer found in the cell walls of plants which is the second most abundant biopolymer on Earth after cellulose. Due to its heterogeneous structure, deconstructing lignin to selected small molecules for use as chemicals or advanced materials has been elusive. This work capitalizes on a “bottom up” approach to the synthesis of lignin oligomers of known bond chemistry to better understand their interfacial interactions.

The potential pharmacological mechanism of lignin deconstruction components and their toxicological …

Clpxp Degradation System In Escherichia Coli, A Study Of Its Energy Sources And Its Applications In Managing The Expression Levels Of Targeted Membrane And Soluble Proteins, Thilini Abeywansha

Theses and Dissertations--Chemistry

ClpXP is an Escherichia coli protease that carries out energy-dependent intracellular proteolysis. In recent years, this system has been widely studied due to its importance as protein regulatory machinery and a virulence factor. Protein substrates of ClpXP contain degrons with a specific protein sequence. SsrA tag is one of the five degrons known to designate proteins for ClpXP degradation. SsrA is an 11 amino acid peptide added to the C-terminus of nascent polypeptide chains translated from aberrant messenger RNAs lacking stop codons via a process called trans-translation.

ClpXP was known to targets only cytosolic proteins with degrons until recently, …

Rational Design Of Small Molecule Disruptors Of Protein-Protein Interactions: Pd-1/Pd-L1; C-Myc, Arid4b, Samuel Ofori

Theses and Dissertations--Chemistry

Protein-protein interactions (PPIs) are vital to many biological processes, including gene expression, and immune reactions to pathogens. There are approximately 650,000 PPIs in humans with pertinent physiological functions. Aberrant expression of PPIs lead to improper function and contribute to a plethora of disease conditions including cancer. Thus, PPIs represent an enormous target space for drug discovery and chemical probes. Direct targeting of clinically relevant PPIs with small molecules remains an unmet medical need. Development of small-molecule inhibitors of PPIs is a challenging enterprise and in most cases considered undruggable due to large protein surfaces, lack of deep binding pockets and …

Investigation Of Multidrug Efflux Transporter Acrb In Escherichia Coli: Assembly, Degradation And Dynamics, Prasangi Irosha Rajapaksha

Theses and Dissertations--Chemistry

The Resistant Nodulation Division (RND) super family member, tripartite AcrA-AcrB-TolC efflux pump, is a major contributor in conferring multidrug-resistance in Escherichia coli. The structure of the pump complex, and drug translocation by functional rotation mechanism have been widely studied. Despite of all these data, the dynamics of the assembly process of the pump and AcrB during functional rotation in the process of drug efflux remains poorly understood. My thesis focuses on understanding the pump assembly process, dynamics of AcrB in functional rotation mechanism, and also investigate the mechanism of degradation of AcrB facilitated by a C-terminal ssrA tag.

In the …

Probing The Assembly, Functional Relevance, And Dynamics Of Acra In Multi Drug Efflux In Escherichia Coli, Isoiza Ojo

Theses and Dissertations--Chemistry

Efflux pumps and low permeability of the outer membrane of gram-negative bacteria are major culprits in drug resistance. The most studied of these multidrug efflux pumps is the AcrAB-TolC, a complex of three proteins, the inner membrane transporter AcrB, the periplasmic adaptor AcrA and outer membrane factor TolC. This pump exports a wide range of molecules such as dyes, detergents, and antibiotics out of the bacteria system into the external environment. AcrB and TolC exist as obligate trimers, but the structure of AcrA during the assembly process is not well defined. My research aims to explore the functional and structural …

Design, Synthesis, And Anticancer Properties Of Ru(Ii) Complexes With Organometallic, “Expanded” Bipyridine, And O,O’-Chelating Ligands, Raphael Ryan

Theses and Dissertations--Chemistry

Cancer is a worldwide public health crisis that requires new and improved drugs to be developed to extend survival rates and improve quality of life for the patient. Platinum-based drugs are used in approximately 50% of cancer treatment regimens. These drugs are highly effective in many kinds of cancer; however, cancers can develop platinum resistance and these drugs have troubling side effects that reduced their use and efficacy. To overcome these disadvantages, many other metals have been studied for their anticancer properties. Notably, the anticancer properties of ruthenium-based agents have drawn considerable attention with multiple ruthenium complexes entering clinical trials. …

Synthesis Of Dual Small Molecule Hybrids To Probe The Synergy Between Dna Repair Enzymes And Ido1, Nathaniel George

Theses and Dissertations--Chemistry

Indoleamine 2 3-dioxygenase (IDO) has recently been highlighted as a promising target for small molecule based immunotherapy. IDO is often coopted by various cancer cells to promote an immune-suppressive environment around tumors. DNA damage repair (DDR) enzymes have recently been targeted for inhibition to promote genetic instability and bolster immune recognition. DDR enzymes such as PARP and POLγ are common inhibition targets due to their direct effects on cellular function. In the process of designing conjugate inhibitors of IDO and DDR enzymes, novel synthetic methodology was developed for the mild deprotection of N-Tert-butyloxycarbonyl (N-BOC) group from various amines. Conjugate …

Tailoring Thermoresponsive Poly(N-Isopropylacrylamide) Toward Sensing Perfluoroalkyl Acids, Dustin Thomas Savage

Theses and Dissertations--Chemical and Materials Engineering

Widespread distribution of poly- and perfluoroalkyl substances (PFAS) in the environment combined with concerns for their potentially negative health effects has motivated regulators to establish strict standards for their surveillance. The United States Environmental Protection Agency issued a cumulative domestic threshold of 70 ppt for water supplies, and this bar is even lower in some local districts and other countries. Monitoring PFAS consequently requires sensitive analytical equipment to meet regulatory specifications, and liquid chromatography with tandem mass spectroscopy (LC/MS/MS) is the most common technique used to satisfy these requirements. Though extremely sensitive, the instrument is often burdened by pretreatment regimens, …

Development Of Novel Polymeric Materials For Their Application In Monitoring And Remediation Of Environmental Pollutants, Rishabh Shah

Theses and Dissertations--Chemical and Materials Engineering

Remediation of environmental pollutants from water is one of the major challenges in the 21st century. Utilizing novel polymeric materials to accomplish this challenge has garnered a lot of interest in recent times. Flexibility in synthesizing as well as functionalizing makes them attractive for their application in pollutant remediation. This work is based on development and characterization of novel crosslinked polymeric as well as linear polymeric materials from biphenyl-based monomers, biphenyl based crosslinker and a temperature responsive monomer (Nisopropylacrylamide (NIPAAm)) for their application in remediation of toxic pollutants such as polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs) and iron oxide nanoparticle …

Determining Material Structures And Surface Chemistry By Genetic Algorithms And Quantum Chemical Simulations, Josiah Jesse Roberts

Theses and Dissertations--Chemistry

With the advent of modern computing, the use of simulation in chemistry has become just as important as experiment. Simulations were originally only applicable to small molecules, but modern techniques, such as density functional theory (DFT) allow extension to materials science. While there are many valuable techniques for synthesis and characterization in chemistry laboratories, there are far more materials possible than can be synthesized, each with an entire host of surfaces. This wealth of chemical space to explore begs the use of computational chemistry to mimic synthesis and experimental characterization. In this work, genetic algorithms (GA), for the former, and …

Developing Synthetic Strategies For Multifaceted Applications Of Stable Gold-Based Complexes, Randall Tyler Mertens

Theses and Dissertations--Chemistry

Development of stable gold-based complexes has been a rapidly advancing field due to the popularity of gold complexes, particularly for use in biomedical research and catalytic transformations. Given that auranofin, a gold(I) complex with FDA approval for the treatment of rheumatoid arthritis is used in the clinic, the development of stable gold-based molecules of clinical relevance is urgently needed. Herein are reported, synthetic strategies used for the development of new classes of gold(I) and gold(III) complexes for advancement in mitochondrial modulation for use as chemotherapeutics as well as application to gold catalysis due to the unique geometry of complexes presented …

Computational Insights On Medicinal Chemistry Targeting Cyp450s, Alexander D. Fenton

Theses and Dissertations--Chemistry

Modern-day medicinal chemistry has provided researchers with a wide variety of tools to not only gather greater insight from their data, but also to generate data in new ways. One such tool is the construction of computational protein models from crystallographic datasets, and their subsequent use to understand the structure-activity relationships of protein-ligand complexes. These models can be utilized for their predictive power to inform the synthesis of, and improvement of, lead compounds. It is the goal of this work to employ such models to the CYP450 enzyme system such that potent and selective inhibitors can be designed, evaluated biologically, …

Plasmon Enhanced Single Molecule Fluorescence In Zero Mode Waveguides (Zmws), Abdullah Masud

Theses and Dissertations--Chemistry

Plasmonic nanostructures are an extensive research focus due to their ability to modify the photophysical properties of nearby fluorophores. Surface plasmons (SP), defined as the collective oscillation of delocalized electrons, are the fundamental characteristic primarily responsible for altering those photophysical properties. Studying fluorophores at the single-molecule level has received significant attention since more specific information can be extracted from single molecule-based studies, which otherwise could be obscured in ensemble studies. However, single-molecule studies are inherently challenging because the signal from a single molecule is usually dim, making it difficult to detect. The situation is even worse in a crowded environment …

Mass Spectrometry Method Development For The Discovery And Characterization Of Secondary Metabolites, Zachary Kelley

Theses and Dissertations--Chemistry

Secondary metabolites are organic compounds produced by an organism for reasons other than growth and development. In plants, secondary metabolites generally act as defense agents produced to deter predators and inhibit other competitive species. For humans, these compounds can often have a beneficial effect and are pursued and utilized as natural pharmaceuticals. The development of sensitive, high-throughput analytical screening methods for plant derived metabolites is crucial for natural pharmaceutical product discovery and plant metabolomic profiling. Here, metabolomic profiling methods were developed using a microfluidic capillary zone electrophoresis device and evaluated against traditional separation approaches. An alkaloid screening assay was constructed …

Flavin Modification And Redox Tuning In The Bifurcating Electron Transfer Flavoprotein From Rhodopseudomonas Palustris: Two Arginines With Different Roles, Nishya Mohamed-Raseek

Theses and Dissertations--Chemistry

Electron bifurcation is considered as a third fundamental mode of energy conservation mechanism in addition to two well-known mechanisms, substrate level phosphorylation and Oxidative phosphorylation, in electron bifurcation endergonic and exergonic redox reactions are coupled. The newly discovered flavin based electron bifurcation in electron transfer flavoproteins (ETFs) helps to reduce low potential ferredoxin, which provides electrons to drive biologically demanding reactions such as atmospheric dinitrogen fixation in diazotroph and methane production in methanogens.

Current research demonstrates the capacity for electron bifurcation in the Rhodopseudomonas palustris ETF (RpalETF) system. RpalETF contains two chemically identical but functionally different FADs: …

Understanding The Role Of Charge On Particle Transport Within Semidilute And Concentrated Biopolymer Solutions And Tau Protein Condensates, Kanthi Nuti

Theses and Dissertations--Chemistry

Biological polymer networks such as mucus, extracellular matrix, nuclear pore complex, and bacterial biofilms, play a critical role in governing the transport of nutrients, biomolecules and particles within cells and tissues. The interactions between particle and polymer chains are responsible for effective selective filtering of particles within these macromolecular networks. This selective filtering is not dictated by steric alone but must use additional interactions such electrostatics, hydrophobic and hydrodynamic effects to control particle transport within biogels. Depending on chemical composition and desired function, biogels use selective filtering to allow some particles to permeate while preventing others from penetrating the biogel. …

The Effects Of Escalated Cocaine Intake On Decision-Making Dynamics, Mcallister Stephens

Theses and Dissertations--Psychology

Cocaine Use Disorder (CUD) is characterized partly by the use of cocaine at the expense of other alternatives, in other words, it is a decision-making pathology (Kalivas & Volkow, 2005). Concurrent choice tasks assess decision-making in a dynamic scenario that more closely resembles real life. Value-based decision-making is an important facet of understanding the addictive properties of drugs of abuse. In order to compare two value-based theories of addiction (habit theory and relative value theory), a concurrent choice task was run in tandem with an escalation procedure. First, animals were trained on a choice task until stable, then trained on …

Associations Between Identity And Future Parenthood Among Lgbtq+ Asian/Pacific Islander Americans, Kay Simon

Theses and Dissertations--Psychology

In recent years, the number of lesbian, gay, bisexual, transgender, and queer (and additional identities; LGBTQ+) identified people and the number of Asian Pacific Islander Americans (APIA) have been increasing in the United States (Movement Advancement Project 2019; Newport, 2018). As the individuals in these demographic groups develop over their lifespan, many will become parents and form families, but little work is currently available on the experiences of LGBTQ+ APIA individuals and future parenthood. Here, I report findings on the perceptions and importance of future parenthood, identity development, identity integration, and microaggressions and/or discrimination (as they relate to racial-ethnic and …

Physiological Stress Responding During Negative Memory Recollection And The Habitual Use Of Psychological Coping Strategies, Kyle P. Rawn

Theses and Dissertations--Psychology

Coping represents an important process for stress: how effectively one copes dictates how a person experiences stress. However, research has not yet examined how a person’s long-term coping habits are related to their physiological stress responding during a particular situation. The current study addresses this through examination of skin conductance level (SCL) trajectories and coping tendencies (i.e. habitual use of coping strategies) during an autobiographical interview. 167 college students completed questionnaires assessing their demographics and their frequency of use for fourteen coping strategies. SCL was collected while participants recalled and discussed a negative family memory from their childhood. Multilevel modeling …

Pharmacokinetics And Reward-Related Behaviors Of Ethanol In Male And Female Japanese Quail (Coturnix Japonica), Shannon Eaton

Theses and Dissertations--Psychology

Ethanol is one of the most widely used and abused drugs. Problem use is associated with many different health problems and the economic burden is in the billions of dollars. Additionally, many people have difficulty controlling their ethanol consumption and about 5% of adults end up with an alcohol use disorder (AUD). Many people with an AUD often find themselves in a cycle of binge, remission, and relapse.

Following ethanol consumption ethanol enters the bloodstream from the small intestine where it gets distributed to peripheral tissues. Ethanol in the bloodstream is cleared from the system by the liver. The primary …

Parent School Involvement, Student School Engagement, And Academic Achievement In Children Adopted From Foster Care By Lesbian And Gay Parents, Cassandra P. Vazquez

Theses and Dissertations--Psychology

Sparse research has examined academic outcomes of children adopted from foster care by lesbian and gay (LG) parents. Children who have experienced foster care are at greater risk for negative outcomes, but investment in academic achievement could help buffer potential adversity. Parent and student engagement with school peaks in middle childhood, so this may be an important period for understanding processes that influence academic achievement. This study explores how LG parents (N = 57) of school-aged children (Mage = 10.56 years) adopted from foster care in the U.S. involve themselves in their child’s school, how this involvement may …

Altering The Distance: Using Construal Level Theory To Examine Conciliatory Policy Support, Brandon Reinkensmeyer

Theses and Dissertations--Psychology

Distancing—a cognitive reappraisal strategy—increases conciliatory policy support (i.e., policies redressing inequity) by reducing anger. Related but distinct research has used construal level theory (CLT), which explains the relationship between psychological distance and mental representations (e.g., events and attitudes), to explore intergroup relations. CLT demonstrates increased psychological distance induces abstract thinking, which leads to high-level construal (HLC) mindsets. HLC mindsets, like distancing, decrease political polarization and prejudice toward out-groups. As both distancing (an appraisal technique) and HLC mindsets (a potential outcome of appraisal techniques) may decrease political polarization and prejudice toward outgroups, across two experiments, the present work investigated whether …

Predicting Material Properties: Applications Of Multi-Scale Multiphysics Numerical Modeling To Transport Problems In Biochemical Systems And Chemical Process Engineering, Tom Pace

Theses and Dissertations--Physics and Astronomy

Material properties are used in a wide variety of theoretical models of material behavior. Descriptive properties quantify the nature, structure, or composition of the material. Behavioral properties quantify the response of the material to an imposed condition. The central question of this work concerns the prediction of behavioral properties from previously determined descriptive properties through hierarchical multi-scale, multiphysics models implemented as numerical simulations. Applications covered focus on mass transport models, including sequential enzyme-catalyzed reactions in systems biology, and an industrial chemical process in a common reaction medium.

The Antithesis Of ‘Business As Usual’: Youth, Class, And Volunteer Organizations In Dar Es Salaam, Tanzania, Chelsea Cutright

Theses and Dissertations--Anthropology

Youth in Tanzania make up the majority of the current growing population and therefore are increasingly a focus of local and international development concern, specifically as the rates of urban growth and unemployment are also increasing. This research builds upon existing anthropological literature, which largely addresses contemporary and urban African youths as “problems” in dire need of governmental intervention and international solutions. Through explorations of the ways in which Tanzanian youth are actively and creatively working to improve their own futures, utilizing their own agency to create opportunities, and solving their own problems in the absence of successful external intercessions, …

"It's About More Than Just Animals": Environmental Politics Of Zoo-Adjacent Conservation(Ists) In The U.S., Dayton D. Starnes Ii

Theses and Dissertations--Anthropology

This research explores the influences of diverse environmental politics in shaping zoo-adjacent conservation activities in the United States. Based upon 13 months of multi-sited ethnographic research, conducted with conservation actors across six states, the researcher investigates and documents how conservation professionals—operating in contexts adjacent to zoological institutions—experience and respond to the socio-environmental implications associated with the cascading effects of global environmental change. In the face of current challenges and uncertain environmental futures—shaped by habitat alterations, ecological transitions, and species declines/extinctions—conservationists are undergoing their own processes of reassessment and reconfiguration of their underpinning philosophies and body of practices that inform their …

Reimagining Care: Surviving And Thriving Among Lgbtq African Americans In Birmingham, Alabama, Stacie Lynn Hatfield

Theses and Dissertations--Anthropology

This dissertation draws on fieldwork with Black LGBTQ identifying individuals and communities in Birmingham, Alabama conducted from 2015-2019 as part of a project that reimagines theories of care. Informed by scholars of Black and feminist studies, I conceive of forms of care as negotiations of survival and tactics of thriving that are worked out in everyday practices and discourses among LGBTQ African Americans. I show how histories of racial inequality and centuries of resistance, surviving, and thriving among communities of African descent intersect with LGBTQ politics, space, and identity to create strategies and places of individual and community care. My …

Social Differentiation Among Rural Maya Households In Chunhuayum, Yucatan, Mexico, During The Late Preclassic Through The Early Classic (300 B.C. – A.D. 600), Céline Lamb

Theses and Dissertations--Anthropology

This dissertation addresses social differentiation among rural residents of Chunhuayum, an ancient Maya village in northwest Yucatan, from the Late Preclassic to the Late Early Classic (300 B.C. – A.D. 600/630). The three axes of social differentiation investigated are household wealth, occupation, and social connectivity to external networks. Using a practice theory approach, my research seeks to identify how material and social practices shaped and expressed social differentiation among Chunhuayum households, as well as how these may have shaped the particular history of Chunhuayum within its regional context. Throughout Chunhuayum’s occupation, residential architecture was the most salient marker of wealth …

"My Gender Is Lesbian": Community Building And The Endurance Of The Lesbian In Queer Times, Adriana Sisko

Theses and Dissertations--Gender and Women's Studies

During 2016, the same year news of lesbian bar closures hit mainstream media, a small cluster of Tumblr users began to discuss a new gender and sexual identity, nonbinary lesbian, to describe those who identify both as nonbinary and as lesbian. Nonbinary lesbians stand at the crossroads of modern and postmodern identity constructs, engaging in contradictions and ambiguities for the sake of authentic self-expression. What does this demonstrate about the evolution of lesbian identity, particularly as lesbian bars continue to close around the United States? This dissertation explores this question by comparing and contrasting the discursive practices and strategies of …

Beyond Choice: An Intersectional Analysis Of Identity And Labor In Online Sex Work, Shawna F. Felkins

Theses and Dissertations--Gender and Women's Studies

This intersectional project seeks to understand the complex labor, social lives, and community building of online sex workers. Building on the work of foundational sex work researchers, this project utilizes in-depth interviews, a survey, social media posts, and published writing and research from online sex workers to understand how marginalization and identity impacts participation and success in online sex work. Providing analysis on how race, gender, class, and ability intersect in the digital sexual marketplace, this project critiques the rise of neoliberal feminism in sex work spaces that stems from the centering of white and otherwise privileged sex workers using …