Physical Sciences and Mathematics Commons^™

Fulleretic Well-Defined Scaffolds: Donor–Fullerene Alignment Through Metal Coordination And Its Effect On Photophysics, Derek E. Williams, Ekaterina A. Dolgopolova, Danielle C. Godfrey, Evgeniya D. Ermolaeva, Perry J. Pellechia Dr., Andrew B. Greytak Prof. Dr., Mark Smith Dr., Stanislav M. Avdoshenko, Dr., Alexey A. Popov Dr., Natalia B. Shustova Prof. Dr.

Faculty Publications

Herein, we report the first example of a crystalline metal–donor–fullerene framework, in which control of the donor–fullerene mutual orientation was achieved through chemical bond formation, in particular, by metal coordination. The 13C cross-polarization magic-angle spinning NMR spectroscopy, X-ray diffraction, and time-resolved fluorescence spectroscopy were performed for comprehensive structural analysis and energy-transfer (ET) studies of the fulleretic donor–acceptor scaffold. Furthermore, in combination with photoluminescence measurements, the theoretical calculations of the spectral overlap function, Förster radius, excitation energies, and band structure were employed to elucidate the photophysical and ET processes in the prepared fulleretic material. We envision that the well-defined fulleretic donor–acceptor …

Iron Uptake And Accumulation Is A Target Of Nickel Toxicity During The Lag Phase In Escherichia Coli, Geoffrey Tuttle Ford

Theses and Dissertations

Various transition metals are essential to all forms of life, and are only required in trace amounts. But this dependence comes as a double-edged sword. All organisms must maintain a careful intracellular quota that does not traverse outside an acceptable range. One transition metal in particular is nickel. The importance of this transition metal has been debated widely and its function varies greatly between organisms, including bacteria. However, the adverse effects caused by over exposure to this metal have been the center of much experimentation in recent years. Still, the mechanisms of nickel toxicity and the subsequent effects on cellular …

Ligand-Induced Magnetic Changes In Metal Thin Films, Fiona Senta Oberbeck-Oxsher

Theses and Dissertations

The investigation of magnetic properties of thin films whose surfaces were modified by organic molecules shows that the addition of any functional group to the surface measurably changes the magnetic properties. The effect often scales with ligand strength and is not limited to surfaces with ferromagnetic properties. Improving upon the technique developed by Knaus et al. [1], a stable and sensitive device was developed to measure this magnetic effect using the planar Hall effect (PHE) in order to shed light onto controversial questions of purported paramagnetism of thiolated gold. There is a measureable non-diamagnetic response of thin gold layers when …

Structural And Functional Studies Of Nicotinamide Adenine Dinucleotide And Streptolysin S Biosynthesis Proteins From Streptococcus Pyogenes, William T. Booth

Theses and Dissertations

Invasive infections caused by Streptococcus pyogenes, also known as Group A Strep (GAS), results in approximately 600,000 deaths annually. With evidence of antibiotic-resistant strains of this bacterium on the rise, there is a need for the identification of new drug targets to control these infections. In our approach we target the quinolinate-salvage pathway (QSP) and the streptolysin S (SLS) biosynthesis pathway. The QSP provides a secondary pathway for NAD+ biosynthesis within this organism; the SLS pathway leads to the formation of a quorum sensing molecule (SLS). We hypothesize that inhibition of the pathways will lead to GAS cell death or …

The Development Of A High Resolution Deep-Uv Spatial Heterodyne Raman Spectrometer, Nirmal Lamsal

Theses and Dissertations

Raman spectroscopy is a light scattering technique that has a huge potential for standoff measurements in applications such as planetary exploration because a Raman spectrum provides a unique molecular fingerprint that can be used for unambiguous identification of target molecules. For this reason, NASA has selected a Raman spectrometer as one of the major instruments for its new Mars lander mission, Mars 2020, in the search for biomarkers that would be the indicators of past or present life. Raman scattering is strongest at UV wavelengths because of the inherent increase in the Raman cross section at shorter wavelengths and because …

Quantum Dot Metrics For Preparative Chemistry And Fluorescence Applications, Yi Shen

Theses and Dissertations

Colloidal semiconductor quantum dots (QDs) are considered to be a promising candidate for bio-imaging and solar cells because of their extraordinary photo-physical properties. The ultimate goal of this dissertation is to design a reliable matrix and a reproducible method to prepare QDs-based biocompatible probe for fluorescence applications. Synthesis of quantum dots requires a large amount of ligands to improve the stability at high temperature. However, for further application and surface modification of QDs, excess ligands must be removed. In this dissertation, I will first describe using gel permeation chromatography (GPC) as a media to purify different types of QDs. A …

From The Sewing Room To The Ballroom, The Evolution Of Ballroom Dance Costumes, Jessica Marie Russell

Senior Theses

Although I have danced all my life, I only began to ballroom dance and dance socially after starting college at the University of South Carolina. While dancing with the Carolina Ballroom Club, I learned some of the history of ballroom dance from our instructors, but I never quite understood how we went from having very conservative court dances to the wide variety of ballroom dances where dancers wear extravagant costumes. I also have been sewing since I was a child; I helped do minor repairs in the costume room for ballet productions, and recently began making clothing for myself. I …

The Chemistry Of Photography, Nichole Marie Witten

Senior Theses

People nowadays are used to instant gratification when it comes to taking photographs. They look at a digital display, click a button, and get a perfectly focused and lighted picture that they can see right away. New technologies enable people to have pocket-sized digital cameras, their smart phones, with them at all times, and they’re easy convenient, and fast. Behind a single lens reflex (SLR) film camera, the scenario is much different. More time is needed in framing the image and adjusting the aperture and shutter speed to get the correct exposure, and the film must be processed darkroom before …

Xenoestrogens From Household Plastics Bind Estrogen Receptors And Affect Cell Proliferation, Susan G. Hurley, Brett R. Lackey, Patricia L. Tate, Sandra L. Gray

Journal of the South Carolina Academy of Science

Xenoestrogens are “foreign” chemicals or compounds that interact with estrogen receptors as either agonists or antagonists to interfere with endocrine system function. Xenoestrogens include phytoestrogens, pesticides, industrial by- products and synthetic estrogens. In this study, consumer plasticware, including baby bottles and food storage containers, were found to release xenoestrogenic compounds that bound to ERα and ERβ and affected cell proliferation.

High Temperature Electrochemical Engineering And Clean Energy Systems, Brenda L. Garcia-Diaz, Luke Olson, Michael Martinez-Rodriguez, Roderick Fuentes, Hector Colon-Mercado, Josh Gray

Journal of the South Carolina Academy of Science

Global power demand is projected to more than double by 2050 and meeting this increased power demand will require maintaining or increasing power output from all existing energy sources while adding a large amount of new capacity. The power sources that have the greatest opportunity to fulfill this demand gap over this time period are clean energy sources including solar and nuclear power. One of the areas of expertise that SRNL has been applying to help with a variety of clean energy technologies is in high temperature electrochemistry. Savannah River National Laboratory (SRNL) in collaboration with industrial and university partners …

Physical Property Control In Core/Shell Inorganic Nanostructures For Fluorescence And Magnetic Targeting Applications, Stephen K. Roberts

Theses and Dissertations

Nanomaterials show immense promise for the future in numerous areas of application. Properties that are unique from the bulk material and are tunable allow for innovation in material design. This thesis will focus on controlling the physical properties of core/shell nanostructures to enhance the utility of the materials.

The first focus is on the impact of different solvent mixtures during the shell growth phase of SILAR based core/shell quantum dot synthesis is studied. Gaining insight into the mechanism for SILAR growth of core/shell nanoparticles allows improved synthetic yields and precursor binding, providing enhanced control to synthesis of core/shell nanoparticles. The …

Investigating The Effects Of Glutathione And Other Key Proteins On Iron Homeostasis And Subcellular Redox Balance In Yeast Model Systems, Kirsten Renee Collins

Theses and Dissertations

Iron homeostasis in Saccharomyces cerevisiae is controlled through several pathways and is important because too much iron can cause cellular damage. Iron homeostasis in yeast is primarily controlled by transcription factors Aft1 and Aft2 which bind to the iron regulon to induce iron uptake when iron levels are low. When iron levels are sufficient, Aft1 and Aft2 are bound and inhibited by monothiol glutaredoxins (Grxs) Grx3 and Grx4. These Grxs are also involved in iron trafficking in the cell and bind to and deliver iron-sulfur clusters to multiple proteins.

The first part of this thesis focuses on determining if excess …

Forensic Characterization Of Dyes From Synthetic Textile Fibers Exposed To Outdoor And Laundering Effects By Ultra Performance Liquid Chromatography And Spectral Analysis, Molly Rebecca Burnip

Theses and Dissertations

Textile fibers found in an investigation are trace evidence that can connect a suspect to a victim or crime scene. Examination involves comparison of the color and morphology of a questioned fiber to a known fiber with optical spectroscopy. Fibers are considered class evidence, so evaluating more characteristics increases their significance as evidence if a match cannot be excluded. Acrylic, nylon, and polyester are textile polymers that require different extraction solvents based on the polymer chemistry. Methods have been developed for UPLC analysis of basic dyes on acrylic, acid on nylon, and disperse dyes on polyester. After microextraction from single …

From Model Systems To Real Catalysts: Bridging The Pressure And Materials Gaps, Audrey S. Duke

Theses and Dissertations

For decades a fundamental understanding of heterogeneous catalysts has been pursued for rational catalyst design using model systems under ultrahigh vacuum (UHV) conditions; however, there exist stark differences between the simplified models investigated under UHV and the industrial catalysts used at high pressures. To bridge these gaps, it becomes essential to utilize progressively more complex materials and to correlate their surface structure and activity using incrementally higher pressure techniques. In this work, both model Pt-Re catalysts and powdered metal-organic frameworks (MOFs) were studied using a suite of traditional UHV surface science techniques in addition to ambient pressure X-ray photoelectron spectroscopy …

Cdk8 And Cdk19 As Novel Regulators Of Bmp4 Induced Emt In Cancer, Anne Elizabeth Serrao

Theses and Dissertations

Bone morphogenetic protein 2/4 (BMP2/4), members of the transforming growth factor β (Tgf-β) superfamily, play a dichotomous role in the progression of cancers through cell growth suppression and the enhancement of tumorigenesis in a variety of cancers. Cyclin dependent kinase 8 (CDK8), a protein kinase that regulates gene transcription, is involved in a variety of cancers including breast and pancreatic cancers as well as in mediating BMP2 signaling via its canonical Smad1 pathway. Our studies show that BMP4 induced EMT signals primarily though Smad1 and that Yap1, a transcriptional co-activator, is necessary for BMP4 induced EMT. Using a highly specific …

Virus Particles Provide Nanotopographical Cues For Osteogenic Differentiation Of Mesenchymal Stem Cells, Kamolrat Metavarayuth

Theses and Dissertations

One key aspect of tissue engineering is to develop biomimetic scaffolding materials that can modulate the proliferation, self-renewal and differentiation of multipotent stem cells into different lineages. Bone marrow derived mesenchymal stem cells (BMSCs) can differentiate into several target cells such as osteoblasts, chondrocytes, adipocytes, and smooth muscle cells. BMSCs are commonly used for in vitro osteogenesis studies in bone tissue engineering field. However the mechanisms and signaling pathways that these cells use to recognize and response to biomaterial surface are still unclear. This dissertation focuses on investigating the effect of chemical and physical cues introduced by virus nanoparticles on …

Using Synthetic Lectins To Investigate Metastatic Potential In Colon Cancer, Erin E. Gatrone

Theses and Dissertations

Cancer is a disease that affects millions of people each year and it is well established that early diagnosis is a key factor towards improving survival rate, with that in mind there is a great need for better diagnostics. From the earliest onset of cancer, changes can be detected in the type and amount of carbohydrates expressed by the cancer cells, i.e., aberrant glycosylation. This process results in differing glycosylation patterns that can be used to detect cancer. Aberrant glycosylation can also greatly affect the potential of cancer cells to metastasize and can be used to stage the disease as …

Synthesis And Utility Of Bis-Urea Macrocycles As Nanoreactors And As Ligands For Metal Organic Materials, Sahan R. Salpage

Theses and Dissertations

“Supramolecular chemistry” powered by non-covalent interactive forces forms the crux in the area of host-guest chemistry. Supramolecular assemblies often have different chemical and physical properties than that of its individual molecular entities and are used to develop novel functional materials. Our expertise involves making functional materials from macrocycles, which contain two urea groups and two rigid C shaped spacer groups. These individual macrocyclic components can self-assemble through hydrogen bonding and other non-covalent interactions to form porous supramolecular assemblies that can be used as confined reaction environments and as ligands to synthesize novel metal organic materials.

This dissertation focuses on studying …

Investigating Structure-Activity Relationships Of Sl11 To Develop A Better Prostate Cancer Diagnostic, Rong Huang

Theses and Dissertations

Prostate cancer is now the second leading cause of cancer death in American men. Since many of the diagnostics either have high false results or risky, it’s important to have better diagnostics and earlier diagnosis of prostate cancer. Aberrant glycosylation is a hallmark of cancer. When cancer occurs, aberrant glycosylation occurs, therefore, glycosylation patterns may provide information about different cancer types and metastatic potential. In order to study and use these glycosylation patterns, the boronic acid functionalized synthetic lectins that can interact with glycans have been developed. The work described here focuses on 1) the structure activities of synthetic lectins …

The Development Of A Miniature Spatial Heterodyne Raman Spectrometer For Applications In Planetary Exploration And Other Extreme Environments, Patrick Doyle Barnett

Theses and Dissertations

Space exploration is arguably one of the most important endeavors our species has ever undertaken. Rapid advances in rocketry and robotics in recent years has allowed for positioning of complex scientific instruments on other planets with a precision that was previously thought impossible. This, along with the need for more sophisticated chemical measurements to achieve the goals of new, more ambitious missions and recent advances in in-situ and remote spectroscopic techniques, has led to a boom in the use of spectroscopic instruments for space exploration. However, future missions to the moons of Jupiter and Saturn, along with other planetary bodies …

Materials Discovery By Crystal Growth: Synthesis, Structure Determination, Magnetic, And Optical Properties Of Complex Lanthanide Containing Oxides, Oxyhydroxides, And Oxyfluorides, Allison Marie Latshaw

Theses and Dissertations

Exploratory crystal growth is a versatile technique and one that can advance materials discovery. Through exploratory crystal growth, it is possible to synthesize many new materials that can have applications in many fields, including solid-state lighting. There exist many adaptations for exploratory crystal growth, including the use of alkali halide flux growth and hydroflux growth, both reported herein. By changing variants in these techniques like reactant ratios, temperature, reaction profile, and, most importantly here, the flux compositions, it is possible to change the products formed or fine tune reactions for product purity.

For solid-state lighting applications, compounds that adopt colorless …

Characterization Of 1-Deoxy-D-Xylulose 5-Phosphate Reductoisomerase (Dxr) From Vibrio Vulnificus, Nikita K. Ussin

Theses and Dissertations

Vibrio vulnificus, a gram-negative bacterium, is the leading cause of seafood-borne illnesses and mortality in the United States. Previous studies of bacterial pathogens have identified a metabolite essential to V. vulnificus growth and function. 1-deoxy-D-xylulose 5-phosphate reductoisomerase (Dxr) is an essential enzyme in the viability of many bacteria and catalyzes the rearrangement of 1-deoxy-D-xylulose 5-phosphate (Dxp) to 2-C-methylerythritol 4-phosphate (MEP) within the MEP pathway found in plants and bacteria. Previous studies have been conducted to characterize Dxr homologs from other pathogens including E. coli, M. tuberculosis, and P. falciparum. Information on the structural and enzymatic characteristics of Dxr from Vibrio …

Applications Of Disposable Pipette Technologies With Lc-Ms/Ms For Forensic And Clinical Analyses Of Biological Matrices, Kaylee R. Mastrianni

Theses and Dissertations

Efficiently hydrolyzing glucuronide metabolites is an important step in the analysis of drugs in urine. Amitriptyline and cyclobenzaprine are both tricyclic compounds with tertiary aliphatic amine groups that are subsequently metabolized to a less common form of glucuronide metabolite, quaternary ammonium linked glucuronides (N+- glucuronide). A collaborative study was conducted to investigate discrepancies in recoveries of these two commonly prescribed compounds in patient urine samples when hydrolyzed with different enzyme from four different commercially available β-glucuronidase sources.

Similarly, there is potential for 6-monoacetylmorphine to be converted to morphine during β-glucuronidase hydrolysis of urine samples. 6-monoacetylmorphine is a unique metabolite of …

Mechanistic Investigation And Potential Application Of A Fatty Acid Decarboxylating Cytochrome P450 Peroxygenase, Chun H. Hsieh

Theses and Dissertations

OleT (CYP152L1) is a recently discovered cytochrome P450 that is structurally similar to peroxide dependent P450s that catalyze fatty acid hydroxylations. OleT has been shown to catalyze the cleavage of n chain length fatty acids to form n-1 alkenes through C-C bond scission of the terminal carboxylate. Using headspace GC-MS and FTIR with isotopically labeled substrates, we have confirmed that OleT metabolizes eicosanoic acid to 1-nonadecene, forming carbon dioxide (CO2) as a co-product of the reaction. No oxygen deriving from peroxide is observed in either product. In order to probe the mechanistic deviation of OleT from P450 peroxygenases, we have …

Investigating Cross Talk Between The High And Low Iron Sensors In Saccharomyces Cerevisiae, John S. Hepburn

Theses and Dissertations

Iron is essential for nearly all life on earth. Cells must maintain sufficient levels of this important nutrient due its function as a central co-factor for many cellular processes. Although iron is extremely plentiful, its poor solubility requires specialized import. On the other side, too much iron inside the cell can lead to the generation of reactive oxygen species (ROS), which have deleterious effects on many cellular functions and have been implicated in a wide variety of diseases such as cancer and Alzheimer’s disease. Using the model eukaryote Saccharomyces cerevisiae, or budding yeast, our research group has accomplished much in …

Surface Chemistry And Transport Properties Of Ii-Vi Semiconductor Nanowires, Pravin Paudel

Theses and Dissertations

Semiconductor nanowires have been widely studied due to their unique properties such as width comparable to critical length-scales, high aspect ratio, and high carrier mobility. These unique properties make them a suitable candidate for various optical and electronic devices like photovoltaics, photodetectors, and field effect transistors. The nanowire surface plays an important role in the performance of these devices because of their high surface to volume ratio. The larger surface area of nanowires may provide better charge separation than planar heterostructures in photovoltaics by providing shorter distance to move for carrier before separation, however, presence of surface states may lead …

Classification Of Natural Phytoplankton Populations With Fluorescence Excitation-Based Imaging Multivariate Optical Computing, Shawna Kathleen Tazik

Theses and Dissertations

Phytoplankton account for the majority of the primary productivity in the ocean and contribute significantly to the global carbon cycle through photosynthesis. A quantitative characterization of phytoplankton cell size and taxonomic composition is essential for understanding marine biogeochemical cycles, quantifying carbon export, and for predicting the ocean’s response to future climate change. Our labs have developed a new instrument for this purpose that combines fluorescence excitation spectroscopy with an all-optical approach to multivariate statistics called multivariate optical computing (MOC). The instrument, known as the Shipboard Streak Imaging Multivariate Optical Computing (SSIMOC) photometer, is a simple filter photometer that images the …

Mass Spectrometry-Based Protein Profiling And Investigations Of Tgf-Ss1-Induced Epithelial-Mesenchymal Transition Signatures In Namru Murine Mammary Gland Epithelial Cells, Matsepo Ramaboli

Theses and Dissertations

Breast cancer is the second-most common cancer and the second-leading cause of cancer-related deaths in women. Despite advances in cancer early detection, prevention and treatment, breast cancer is still a major health challenge due to low survival caused by breast cancer metastasis. This warrants critical attention and intervention. From the proteomic standpoint, a protein-based multiplex system that provides large array of informative signals for cancer identification and prognosis is still limited. In this dissertation work, we developed two mass spectrometry-based strategies involving chemical biology tools for rapid protein fingerprinting of breast cancer cell lines, and for probing the O-linked N-acetylglucosamine …

Improved Systems For On-Site Raman Measurements, William Joshua Huntington

Theses and Dissertations

The need to development lightweight miniature sensors for spectrometers for use in hazardous environments such as war zones, industrial settings, and space exploration is ever growing. This thesis will present studies aimed at improving Raman instruments for such applications by reducing the size, weight, and power consumption of the instrument. The two methods described here include the utilization of a light emitting diode (LED) source for Raman spectroscopy and a new type of Raman gas sensor.

Chapter one describes a new Raman spectrometer that utilizes an LED for Raman excitation coupled to the SHRS. LEDs are highly divergent broadband , …

Estimation Of The Quantum Effects Of Nuclei In Large Molecular Systems, Bing Gu

Theses and Dissertations

Chemical dynamics, in principle, should be understood by solving the time-dependent Schrödinger equation for a molecular system, describing motion of the nuclei and electrons. However, the computational efforts to solve this partial second-order differential equation scales exponentially with the system size, which prevents us from getting exact numerical solutions for systems larger than 4-5 atoms. Thus, approximations simplifying the picture are necessary. The so-called Born-Oppenheimer approximation, separating motion of the electrons and nuclei is the central one: solution to the electronic Schrödinger equation defines the potential energy surface on which the nuclear motion unfolds, and there are standard quantum chemistry …