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Full-Text Articles in Physical Sciences and Mathematics

Managing Health Locus Of Control In Patient-Provider Relationships, James Wallace Sep 2021

Managing Health Locus Of Control In Patient-Provider Relationships, James Wallace

USF Tampa Graduate Theses and Dissertations

Patient locus of control is a strong determinant of health outcomes, yet health care professionals do not typically address it in care plans. In fact, management of most medical conditions is hindered because the treating physician has little information about the patient’s locus of control. This research addresses the question “How can locus of control be used to enable health care practitioners to improve medical outcomes?”

Research Methodology. Using an engaged scholarship approach incorporating the Elaborated Action Design Research methodology, the research drives the guided, emergent design of a novel protocol and two separate artifacts for management of health locus …


Environmental Factors Shaping Bacterial, Archaeal And Fungal Community Structure In Hydrothermal Sediments Of Guaymas Basin, Gulf Of California, Gustavo A. Ramírez, Paraskevi Mara, Taylor Sehein, Gunter Wegener, Christopher R. Chambers, Samantha B. Joye, Richard N. Peterson, Aurélie Philippe, Gaëtan Burgaud, Virginia P. Edgcomb, Andreas P. Teske Sep 2021

Environmental Factors Shaping Bacterial, Archaeal And Fungal Community Structure In Hydrothermal Sediments Of Guaymas Basin, Gulf Of California, Gustavo A. Ramírez, Paraskevi Mara, Taylor Sehein, Gunter Wegener, Christopher R. Chambers, Samantha B. Joye, Richard N. Peterson, Aurélie Philippe, Gaëtan Burgaud, Virginia P. Edgcomb, Andreas P. Teske

Marine Science

The flanking regions of Guaymas Basin, a young marginal rift basin located in the Gulf of California, are covered with thick sediment layers that are hydrothermally altered due to magmatic intrusions. To explore environmental controls on microbial community structure in this complex environment, we analyzed site- and depth-related patterns of microbial community composition (bacteria, archaea, and fungi) in hydrothermally influenced sediments with different thermal conditions, geochemical regimes, and extent of microbial mats. We compared communities in hot hydrothermal sediments (75-100 °C at ~40 cm depth) covered by orange-pigmented Beggiatoaceae mats in the Cathedral Hill area, temperate sediments (25-30°C at ~40 …


Genotype, Age, Genetic Background, And Sex Influence Epha2-Related Cataract Development In Mice, Alpana Dave, Jamie E. Craig, Mohammad Alamein, Karina Skrzypiec, Justin Beltz, Annalise Pfaff, Kathryn P. Burdon, Nuran Ercal, Robb U. De Iongh, Shiwani Sharma Sep 2021

Genotype, Age, Genetic Background, And Sex Influence Epha2-Related Cataract Development In Mice, Alpana Dave, Jamie E. Craig, Mohammad Alamein, Karina Skrzypiec, Justin Beltz, Annalise Pfaff, Kathryn P. Burdon, Nuran Ercal, Robb U. De Iongh, Shiwani Sharma

Chemistry Faculty Research & Creative Works

PURPOSE. Age-related cataract is the leading cause of blindness worldwide. Variants in the EPHA2 gene increase the disease risk, and its knockout in mice causes cataract. We investigated whether age, sex, and genetic background, risk factors for age-related cataract, and Epha2 genotype influence Epha2-related cataract development in mice.

METHODS. Cataract development was monitored in Epha2+/+, Epha2+/-, and Epha2-/- mice (Epha2Gt(KST085)Byg) on C57BL/6J and FVB:C57BL/6J (50:50) backgrounds. Cellular architecture of lenses, endoplasmic reticulum (ER) stress, and redox state were determined using histological, molecular, and analytical techniques.

RESULTS. Epha2-/- and Epha2+/- …


Logics Of Resource And Justification, Hirohiko Kushida Sep 2021

Logics Of Resource And Justification, Hirohiko Kushida

Dissertations, Theses, and Capstone Projects

It is a well-known result by G ̈odel in 1933 that the Intuitionistic Logic can be embedded into a system which is essentially equivalent to the modal logic S4. This can be considered to be an attempt to provide a provability semantics to the Intuitionistic Logic. This work had caused some problems: the exact arithmetical meaning of the Intuitionistic Logic and S4, the exact axiomatization of formal provability in formal arithmetic and the standard model of arithmetic. These days the arithmetical interpretation has been extended and generalized to epistemological interpretation for various modal logics, which resulted in various systems of …


Enhanced Platinum (Ii) Drug Delivery For Anti-Cancer Therapy, Marek T. Wlodarczyk Sep 2021

Enhanced Platinum (Ii) Drug Delivery For Anti-Cancer Therapy, Marek T. Wlodarczyk

Dissertations, Theses, and Capstone Projects

Over the years, anti-cancer therapies have improved the overall survival rate of patients. Nevertheless, the traditional free drug therapies still suffer from side effects and systemic toxicity, resulting in low drug dosages in the clinic. This often leads to suboptimal drug concentrations reaching cancer cells, contributing to treatment failure and drug resistance. Among available anti-cancer therapies, metallodrugs are of great interest. Platinum (II)-based agents are highly potent and are used to treat many cancers, including ovarian cancer (OC). Cisplatin (cis-diaminedichloroplatinum (II)) is the first Food and Drug Administration (FDA)-approved metallodrug for treatment of solid tumors, and its mechanism …


Evaluation Of The Potential Of Automated Sem-Eds Analysis For The Discrimination Of Inorganic Soil Particles, Anna S. Duggar Sep 2021

Evaluation Of The Potential Of Automated Sem-Eds Analysis For The Discrimination Of Inorganic Soil Particles, Anna S. Duggar

Dissertations, Theses, and Capstone Projects

Soil, that complex mixture of minerals, organic particles, chemicals, and anthropogenic materials, is ubiquitous and easily transferred, which gives it forensic relevance. Forensic soil analysis has traditionally included the identification and comparison of both organic and inorganic components, the inorganic portion being most commonly examined by light microscopy and other instrumental techniques. Predominantly, the inorganic materials in soil are naturally-occurring minerals, contributed as grains from the surrounding bedrock, which gives a soil its regional character. That parent material then undergoes physical, chemical, and anthropogenic changes producing wide geographic variation within a single region. This variation forms the basis for potential …


Connecting Communities To Coastal Resilience: Enhancing Sustainability Through Public Participation In Salt Marsh Management And Restoration In Suffolk County, Ny, Jennifer L. Mcgivern Sep 2021

Connecting Communities To Coastal Resilience: Enhancing Sustainability Through Public Participation In Salt Marsh Management And Restoration In Suffolk County, Ny, Jennifer L. Mcgivern

Dissertations, Theses, and Capstone Projects

Coastal resiliency is becoming significantly more critical to the livelihood of coastal communities as the frequency and intensity of storm events increases and is exacerbated by rising sea levels due to climate change. In October 2012 Superstorm Sandy impacted the New York-New Jersey area costing over $70 billion in storm damages and 147 lives lost, as storm surges surpassed record highs for the region. Protruding more than 100 miles into the Atlantic Ocean with over 1,000 miles of shoreline, Long Island is particularly vulnerable to the increasingly ferocious and numerous storms as well as the rising sea levels that climate …


Wave Excitation And Dynamics In Disordered Systems, Yiming Huang Sep 2021

Wave Excitation And Dynamics In Disordered Systems, Yiming Huang

Dissertations, Theses, and Capstone Projects

This thesis presents studies of the field and energy excited in disordered systems as well as the dynamics of scattering.

Dynamic and steady state aspects of wave propagation are deeply connected in lossless open systems in which the scattering matrix is unitary. There is then an equivalence among the energy excited within the medium through all channels, the Wigner time delay, which is the sum of dwell times in all channels coupled to the medium, and the density of states. But these equivalences fall away in the presence of material loss or gain. In this paper, we use microwave measurements, …


Assessing The Water Quality Of Three Bar-Built Estuaries In The Central Coast Of California, Micaelina Sarmiento Martinez Sep 2021

Assessing The Water Quality Of Three Bar-Built Estuaries In The Central Coast Of California, Micaelina Sarmiento Martinez

Master of Science in Environmental Sciences and Management Projects

Estuaries are coastal confluences with innumerable ecosystem services. With the continuous change in land use including the increasing number of people moving to live in coastal areas and on-going agricultural operations, these coastal systems are being adversely impacted. Climate change is also negatively affecting estuaries. Subsequently, this research study assessed the water quality, monthly, at three different locations of three bar-built estuaries in the Central Coast of California. Water quality was evaluated by the change in chlorophyll-a, nitrogen, phosphorus, pH, temperature, dissolved oxygen, and specific conductivity over the course of 19 months. The eutrophication potential and the role of open …


Detecting Stance On Covid-19 Vaccine In A Polarized Media, Rodica Ceslov Sep 2021

Detecting Stance On Covid-19 Vaccine In A Polarized Media, Rodica Ceslov

Dissertations, Theses, and Capstone Projects

The growing polarization in the United States has been widely reported. Media coverage plays an important role in shaping public opinion and influences public debates on complex and unfamiliar topics. There are some benefits to individuals and society from political polarization and conflict between opposing viewpoints. However, recent research has primarily highlighted the negative consequences of polarization which reached an all-time high. One such topic is the Covid-19 vaccine which was developed in record time, and the public learned about its safety and possible risks through the media coverage.

In this capstone, we examine U.S. news media coverage on the …


Instabilities Of Overturned Traveling Waves, Tyler B. Pierce Sep 2021

Instabilities Of Overturned Traveling Waves, Tyler B. Pierce

Theses and Dissertations

The instabilities of overturned traveling waves are determined by the use of spectral methods. Two separate numerical methods, Spectral Stability Analysis and Dynamic Stability Analysis, are used to assess the instabilities of branches of waves solved from conformally-mapped Euler equations. The branches of waves with Bond number less than two were found to be spectrally stable to super-harmonic perturbations. The branches of waves with Bond number in [2,3) had some waves that were stable and some that were unstable. All overturned waves with Bond number greater than or equal to two were unstable.


Analysis Of Space To Ground Ladar Performance With Non-Traditional Optics, Prayant P.S. Hanjra Sep 2021

Analysis Of Space To Ground Ladar Performance With Non-Traditional Optics, Prayant P.S. Hanjra

Theses and Dissertations

Two major obstacles to space-based LADAR systems are low power returns from targets and limitations on size and weight for transporting large optics into orbit. Signals incur significant losses during roundtrip propagation through the atmosphere and from diffuse scattering off of targets. Models, such as the Laser Environmental Effects Definition and Reference (LEEDR) simulator and High Energy Laser End to End Operational Simulation (HELEEOS) can predict these losses due to the atmosphere and optical components for a variety of atmospheric and environmental conditions across the globe. A transmissometer is used to validate these models. These losses are used to determine …


In-Game Social Interactions To Facilitate Esl Students' Morphological Awareness, Language And Literacy Skills, Yolanda A. Rankin, Sana Tibi, Casey Kennington, Na-Eun Han Sep 2021

In-Game Social Interactions To Facilitate Esl Students' Morphological Awareness, Language And Literacy Skills, Yolanda A. Rankin, Sana Tibi, Casey Kennington, Na-Eun Han

Computer Science Faculty Publications and Presentations

Video games that require players to utilize a target or second language to complete tasks have emerged as alternative pedagogical tools for Second Language Acquisition (SLA). With the exception of vocabulary acquisition, much of the prior research in game-based SLA fails to gauge students' literacy skills, specifically their morphological awareness or understanding of the smallest meaningful linguistic units (e.g., prefixes, suffixes, and roots). Given this shortcoming, we utilize a two-player online game to facilitate social interactions between Native English Speakers (NES) and English as a Second Language (ESL) students as a mechanism to generate ESL students' written output in the …


Statistical Mechanics Of One-Dimensional Quantum Droplets, T. Mithun, Simeon I. Mistakidis, P. Schmelcher, P. G. Kevrekidis Sep 2021

Statistical Mechanics Of One-Dimensional Quantum Droplets, T. Mithun, Simeon I. Mistakidis, P. Schmelcher, P. G. Kevrekidis

Physics Faculty Research & Creative Works

We Study The Statistical Mechanics And The Dynamical Relaxation Process Of Modulationally Unstable One-Dimensional Quantum Droplets Described By A Modified Gross-Pitaevskii Equation. To Determine The Classical Partition Function Thereof, We Leverage The Semi-Analytical Transfer Integral Operator (TIO) Technique. The Latter Predicts A Distribution Of The Observed Wave-Function Amplitudes And Yields Two-Point Correlation Functions Providing Insights Into The Emergent Dynamics Involving Quantum Droplets. We Compare The Ensuing TIO Results With The Probability Distributions Obtained At Large Times Of The Modulationally Unstable Dynamics As Well As With The Equilibrium Properties Of A Suitably Constructed Langevin Dynamics. We Find That The Instability Leads …


Detrital Zircon Record Of Magmatism And Sediment Dispersal Across The North American Cordilleran Arc System (28–48°N), T. M. Schwartz, Kathleen D. Surpless, J. P. Colgan, S. A. Johnstone, C. S. Holm-Denoma Sep 2021

Detrital Zircon Record Of Magmatism And Sediment Dispersal Across The North American Cordilleran Arc System (28–48°N), T. M. Schwartz, Kathleen D. Surpless, J. P. Colgan, S. A. Johnstone, C. S. Holm-Denoma

Earth and Environmental Geosciences Faculty Research

As zircon U-Pb geochronology has become a leading method in sediment provenance studies and basin analysis over the past 20 years, the volume of detrital zircon data made available in published literature has enabled researchers to go beyond source-to-sink provenance studies to explore increasingly complex geologic problems. In this review, we utilize the growing body of detrital zircon data acquired from Jurassic-Paleocene forearc and foreland basin strata of the North American Cordillera to investigate the Mesozoic to earliest Cenozoic evolution of the arc and its associated basins between 28°N and 48°N. Our compilation includes 830 detrital zircon samples (101,898 individual …


Catastrophic Beach Sand Losses Due To Erosion From Predicted Future Sea Level Rise (0.5–1.0 M), Based On Increasing Submarine Accommodation Spaces In The High-Wave-Energy Coast Of The Pacific Northwest, Washington, Oregon, And Northern California, Usa, Curt D. Peterson, Don Joseph Pettit, Kara E. P. Kingen, Sandy Vanderburgh, Chuck Rosenfeld Sep 2021

Catastrophic Beach Sand Losses Due To Erosion From Predicted Future Sea Level Rise (0.5–1.0 M), Based On Increasing Submarine Accommodation Spaces In The High-Wave-Energy Coast Of The Pacific Northwest, Washington, Oregon, And Northern California, Usa, Curt D. Peterson, Don Joseph Pettit, Kara E. P. Kingen, Sandy Vanderburgh, Chuck Rosenfeld

Geology Faculty Publications and Presentations

The U.S. Pacific Northwest (PNW) coastline (1000 km) has been analyzed for conditions that could impact beach erosion from potential near-future (100 year) sea level rise (SLR). Heavy mineral analysis of river, beach, and shelf samples (n = 105) establish the sources of the beach deposits. River bedload discharge and intervening estuarine sinks for river sand supplies (n = 31) were normalized to the one century time interval. Twenty-six subcell beaches (657 km in combined length) were surveyed (153 profiles) for beach sand widths (20–412 m) and sand cross-sectional areas (20–1810 m2 ) above wave-cut platforms and/or 0 m tidal …


Dissecting Monomer-Dimer Equilibrium Of An Rnase P Protein Provides Insight Into The Synergistic Flexibility Of 5’ Leader Pre-Trna Recognition, Danyun Zeng, Ainur Abzhanova, Benjamin P. Brown, Nicholas J. Reiter Sep 2021

Dissecting Monomer-Dimer Equilibrium Of An Rnase P Protein Provides Insight Into The Synergistic Flexibility Of 5’ Leader Pre-Trna Recognition, Danyun Zeng, Ainur Abzhanova, Benjamin P. Brown, Nicholas J. Reiter

Chemistry Faculty Research and Publications

Ribonuclease P (RNase P) is a universal RNA-protein endonuclease that catalyzes 5’ precursor-tRNA (ptRNA) processing. The RNase P RNA plays the catalytic role in ptRNA processing; however, the RNase P protein is required for catalysis in vivo and interacts with the 5’ leader sequence. A single P RNA and a P protein form the functional RNase P holoenzyme yet dimeric forms of bacterial RNase P can interact with non-tRNA substrates and influence bacterial cell growth. Oligomeric forms of the P protein can also occur in vitro and occlude the 5’ leader ptRNA binding interface, presenting a challenge in accurately defining …


Electronic Structures And Spectroscopic Signatures Of Diiron Intermediates Generated By O2 Activation Of Nonheme Iron(Ii)–Thiolate Complexes, Danushka M. Ekanayake, Dao Pham, Andrew L. Probst, Joshua R. Miller, Cordina V. Popescu, Adam T. Fiedler Sep 2021

Electronic Structures And Spectroscopic Signatures Of Diiron Intermediates Generated By O2 Activation Of Nonheme Iron(Ii)–Thiolate Complexes, Danushka M. Ekanayake, Dao Pham, Andrew L. Probst, Joshua R. Miller, Cordina V. Popescu, Adam T. Fiedler

Chemistry Faculty Research and Publications

The activation of O2 at thiolate–ligated iron(II) sites is essential to the function of numerous metalloenzymes and synthetic catalysts. Iron–thiolate bonds in the active sites of nonheme iron enzymes arise from either coordination of an endogenous cysteinate residue or binding of a deprotonated thiol-containing substrate. Examples of the latter include sulfoxide synthases, such as EgtB and OvoA, that utilize O2 to catalyze tandem S–C bond formation and S-oxygenation steps in thiohistidine biosyntheses. We recently reported the preparation of two mononuclear nonheme iron–thiolate complexes (1 and 2) that serve as structural active-site models of substrate-bound EgtB …


Towards Cnl-Based Verbalization Of Computational Contracts, Inari Listenmaa, Maryam Hanafiah, Regina Cheong, Andreas Kallberg Sep 2021

Towards Cnl-Based Verbalization Of Computational Contracts, Inari Listenmaa, Maryam Hanafiah, Regina Cheong, Andreas Kallberg

Centre for Computational Law (2022-2025)

We present a CNL, which is a component of L4, a domain-specific programming language for drafting laws and contracts. Along with formal verification, L4’s core functionalities include natural language generation. We present the NLG pipeline and an interactive process for ambiguity resolution.


Classroom And Computational Investigations Of Camel Up, Thomas J. Clark Sep 2021

Classroom And Computational Investigations Of Camel Up, Thomas J. Clark

Faculty Work Comprehensive List

Camel Up is a popular board game in which players score points by betting on camels which move randomly via a dice mechanic. The game is available both as a board game [1], as well as an IOS App [2]. Because of the random nature of the camels it is generally difficult to play optimally, but one can nevertheless develop various strategies. Probabilistic knowledge proves helpful in assigning relative value to potential game choices. We discuss how this game can be used to motivate and provide context for learning about the concepts of conditional probability and expected value. Also we …


Robust And Ethical Data Governance Critical To Growth In Digital Age, Themin Suwardy, Melvin Yong Sep 2021

Robust And Ethical Data Governance Critical To Growth In Digital Age, Themin Suwardy, Melvin Yong

Research Collection School Of Accountancy

With increasing digitalisation, and companies collecting an ever-increasing amount of their customer and business data, organisations have to become more accountable to stakeholders such as regulators, customers and investors on the issue of data. Observers say expectations are also increasing, with incidents of data breaches capturing much media attention. Just as corporate governance encompasses more than just compliance, experts say data governance is more than just data protection and security but also about creating value.


Data-Driven Management—A Dynamic Occupancy Approach To Enhanced Rabies Surveillance Prioritization, Amy J. Davis, Jordana D. Kirby, Richard B. Chipman, Kathleen M. Nelson, Amy T. Gilbert Sep 2021

Data-Driven Management—A Dynamic Occupancy Approach To Enhanced Rabies Surveillance Prioritization, Amy J. Davis, Jordana D. Kirby, Richard B. Chipman, Kathleen M. Nelson, Amy T. Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

Rabies lyssavirus (RABV) is enzootic in raccoons across the eastern United States. Intensive management of RABV by oral rabies vaccination (ORV) has prevented its spread westward and shown evidence of local elimination in raccoon populations of the northeastern US. The USDA, Wildlife Services, National Rabies Management Program (NRMP) collaborates with other agencies to implement broad-scale ORV and conducts extensive monitoring to measure the effectiveness of the management. Enhanced Rabies Surveillance (ERS) was initiated during 2005 and updated in 2016 to direct surveillance efforts toward higher-value specimens by assigning points to different methods of encountering specimens for collection (strange-acting, roadkill, surveillance-trapped, …


Piecewise Linear Manifold Clustering, Artyom Diky Sep 2021

Piecewise Linear Manifold Clustering, Artyom Diky

Dissertations, Theses, and Capstone Projects

This work studies the application of topological analysis to non-linear manifold clustering. A novel method, that exploits the data clustering structure, allows to generate a topological representation of the point dataset. An analysis of topological construction under different simulated conditions is performed to explore the capabilities and limitations of the method, and demonstrated statistically significant improvements in performance. Furthermore, we introduce a new information-theoretical validation measure for clustering, that exploits geometrical properties of clusters to estimate clustering compressibility, for evaluation of the clustering goodness-of-fit without any prior information about true class assignments. We show how the new validation measure, when …


Developing Dynamical Probes Of Quantum Spin Liquids Inspired By Techniques From Spintronics, Joshua Aftergood Sep 2021

Developing Dynamical Probes Of Quantum Spin Liquids Inspired By Techniques From Spintronics, Joshua Aftergood

Dissertations, Theses, and Capstone Projects

We theoretically study low dimensional insulating spin systems using spin fluctuations as a probe of the spin dynamics. In some systems, low dimensionality in conjunction with other quantum fluctuation enhancing effects impedes spontaneous generation of long range magnetic ordering down to zero absolute temperature. In particular, we focus on exotic spin systems hosting mobile, fractionalized spin excitations above their ground state, and ultimately show that techniques already commonplace in spintronics can be utilized in the context of quantum magnetism to develop probes of exotic ground states.

We initially consider quantum spin chains (QSCs), and examine a system of two exchange-coupled …


A Geometric Model For Real And Complex Differential K-Theory, Matthew T. Cushman Sep 2021

A Geometric Model For Real And Complex Differential K-Theory, Matthew T. Cushman

Dissertations, Theses, and Capstone Projects

We construct a differential-geometric model for real and complex differential K-theory based on a smooth manifold model for the K-theory spectra defined by Behrens using spaces of Clifford module extensions. After writing representative differential forms for the universal Pontryagin and Chern characters we transgress these forms to all the spaces of the spectra and use them to define an abelian group structure on maps up to an equivalence relation that refines homotopy. Finally we define the differential K-theory functors and verify the axioms of Bunke-Schick for a differential cohomology theory.


Monte Carlo, Molecular Dynamics And Network Analysis Of The Gramicidin Water Channel And Proton Transfer Pathways To Qb In Photosynthetic Reaction Centers, Yingying Zhang Sep 2021

Monte Carlo, Molecular Dynamics And Network Analysis Of The Gramicidin Water Channel And Proton Transfer Pathways To Qb In Photosynthetic Reaction Centers, Yingying Zhang

Dissertations, Theses, and Capstone Projects

Water molecules play a key role in all biochemical processes. They help define the shape of proteins, and they are reactant or product in many reactions and are released as ligands are bound. They facilitate transfer of protons through transmembrane proton channel, pump and transporter proteins. Continuum electrostatics (CE) force fields such as used in MCCE (Multi-Conformation Continuum Electrostatics) capture electrostatic interactions in biomolecules with an implicit solvent, to give the averaged solvent water equilibrium properties. Hybrid CE methods can use explicit water molecules within the protein surrounded by implicit solvent. These hybrid methods permit the study of explicit hydrogen …


Carbon And Nitrogen Dynamics Of A Lagoon Salt Marsh In Davenport, California, Mark D. Gormley Sep 2021

Carbon And Nitrogen Dynamics Of A Lagoon Salt Marsh In Davenport, California, Mark D. Gormley

Dissertations, Theses, and Capstone Projects

Wetlands are complex environments that play a critical role in regulating the global biogeochemical cycle of carbon (C) and nitrogen (N). Wetlands are critical contributors to global climate change and atmospheric chemistry since they store as much as 33% of the world’s soil organic carbon (SOC), release more than 20% of the atmospheric methane (CH4), and produce nitrous oxide (N2O), an extremely potent greenhouse gas (GHG). Despite the enormous radiative forcing potential of carbon dioxide (CO2), CH4 and N2O derived from wetlands, uncertainties over the rates of C sequestration and GHG …


Don't Sell Them Short, There's More To Bacterial Natural Products Than Antibiotics, Alison Clare Domzalski Sep 2021

Don't Sell Them Short, There's More To Bacterial Natural Products Than Antibiotics, Alison Clare Domzalski

Dissertations, Theses, and Capstone Projects

Recent genomic studies of microbiomes have revealed an overwhelming number of biosynthetic genes of unknown function. Most of these “cryptic” biosynthetic genes are not expressed in laboratory monocultures of individual microbes. Thus, there remains tremendous untapped potential for natural products discovery. Here we employ mixed microbial culture (MMC) as a simple yet powerful approach to awaken cryptic biosynthetic gene clusters. Our preliminary studies demonstrated that arrays of metabolites could be induced in MMCs upon environmental cues, such as surface adhesion. Using this system, we have screened, identified, and isolated bioactive bacterial metabolites, which were characterized structurally and biologically. Of the …


Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles Sep 2021

Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles

Dissertations, Theses, and Capstone Projects

Hypersurface Photolithography (HP) is a printing method for fabricating structures and patterns composed of soft materials bound to solid surfaces and with ~1 micrometer resolution in the x, y, and z dimensions. This platform leverages benign, low intensity light to perform photochemical surface reactions with spatial and temporal control of irradiation, and, as a result, is particularly useful for patterning delicate organic and biological material. In particular, surface- initiated controlled radical polymerizations can be leveraged to create arbitrary polymer and block- copolymer brush patterns. Chapter 1 will review the advances in instrumentation architectures from our group that have made these …


Nonlinear Optical Studies Of Interfacial Ferroelectricity And Strain Distribution In Perovskite Dielectric Films, Tony Le Sep 2021

Nonlinear Optical Studies Of Interfacial Ferroelectricity And Strain Distribution In Perovskite Dielectric Films, Tony Le

Dissertations, Theses, and Capstone Projects

Dielectric and ferroelectric perovskite films have been model energy storage structures for their low-dielectric loss, extremely high charge-discharge speed, and good temperature stability, yet there is still much to understand about the material’s limitations. This dissertation presents a detailed understanding of the strain-induced ferroelectricity at the boundary between a strontium titanate (SrTiO3) ultrathin film epitaxially grown on a germanium (Ge) substrate through optical second harmonic generation (SHG), and the polydomain distribution in the Zr-doped BaTiO3 (BZT) films by time-resolved pump-probe spectroscopy.

First, SHG measurements were performed to reveal interfacial ferroelectricity in the epitaxial SrTiO3/Ge (100) …