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Design, Construction, And Characterization Of A Combined Mini-Co₂/Voc Sensor And Gas Chromatograph For Field Research, Rishi Basdeo, Michael Hampton 2020 University of Central Florida

Design, Construction, And Characterization Of A Combined Mini-Co₂/Voc Sensor And Gas Chromatograph For Field Research, Rishi Basdeo, Michael Hampton

Digital Repository: Showcase of Undergraduate Research Excellence

No abstract provided.


Gc-Ms Analysis Of Synthesized Biodiesel, Courtney R. Whetstine 2020 State University of New York College at Buffalo - Buffalo State College

Gc-Ms Analysis Of Synthesized Biodiesel, Courtney R. Whetstine

Forensic Science Master's Projects

Biodiesel is an alternative energy resource that can replenish depleting natural petroleum storage. Synthesis of biodiesel is cost-efficient as it can be chemically converted from renewable wastes, such as vegetable oil or animal fat. These fuels are also biodegradable and the exhaust emissions from biodiesel are non-toxic and environmentally-friendly. Biodiesel is a stable fuel that performs reliably in all diesel engines. Biodiesel is also easy to synthesize, safe to handle, and works with diesel fuel storage and pumping systems. The United States has an abundance of vegetable oils that have not been widely used to our advantage. Additionally, fast-food restaurants …


Capillary Electrophoresis Analysis Of Proteins Using Phospholipid Based Materials, Cassandra L. Crihfield 2020 West Virginia University

Capillary Electrophoresis Analysis Of Proteins Using Phospholipid Based Materials, Cassandra L. Crihfield

Graduate Theses, Dissertations, and Problem Reports (ETD)

Capillary electrophoresis has many advantages that make it a powerful technique for the analysis of proteins, which is challenging due to the natural heterogeneity of proteins. The small sample volume required for each analysis (nano- and pico-liter), fast separation times (<30 >min), and ability to couple the separation to mass spectrometry are all factors that make capillary electrophoresis an ideal technology for protein separations. Capillary zone electrophoresis and capillary gel electrophoresis are the two most commonly employed modes for protein analysis and allow for rapid, high resolution separations that can be automated. This makes capillary electrophoresis ideal for meeting the …


Development And Implementation Of A Novel Voltage-Free Interface For Capillary Electrophoresis-Mass Spectrometry Separations Of Proteins, Courtney J. Kristoff 2020 West Virginia University

Development And Implementation Of A Novel Voltage-Free Interface For Capillary Electrophoresis-Mass Spectrometry Separations Of Proteins, Courtney J. Kristoff

Graduate Theses, Dissertations, and Problem Reports (ETD)

Capillary electrophoresis-mass spectrometry is a powerful technique for high-throughput and high efficiency separations combined with structural identification. Electrospray ionization is the primary interface used to couple capillary electrophoresis to mass analyzers; however, improved designs continue to be reported. A new interfacing method based on vibrating sharp-edge spray ionization is presented in this work to overcome the challenges of decoupling applied voltages and to enhance the compatibility with separations performed at near-neutral pH. The versatility and ease of use of this ionization source is demonstrated using β-blockers, peptides, and proteins. The cationic β-blocker pindolol was injected electrokinetically and detected at concentrations …


Genetic And Biochemical Characterization Of Ergot Alkaloid Synthesizing Fungi And Their Symbionts, Matthew Duane Maust 2020 West Virginia University

Genetic And Biochemical Characterization Of Ergot Alkaloid Synthesizing Fungi And Their Symbionts, Matthew Duane Maust

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ergot alkaloids are fungal tryptophan derived toxins which affect mammalian circulation and neurotransmission. These compounds are biosynthesized by a conserved genetic pathway, known as the ergot alkaloid synthesis (EAS) pathway by fungi belonging to the ascomycete families Trichocomaceae and Clavicipitaceae. Several Ipomoea species and related plants in the morning glory family harbor vertically transmitted symbiotic fungi in the genus Periglandula, also members of Clavicipitaceae, that produce ergot alkaloids. Metabolomic analysis of seeds identified a previously uncharacterized glycoside form of the pharmaceutically important ergot alkaloid, ergonovine. Several species belonging to the fungal genus Metarhizium have recently been shown to have the …


Protein/Peptide Characterization Using Mass Spectrometry And Molecular Dynamics Simulations, Ahmad Kiani Karanji 2020 West Virginia University

Protein/Peptide Characterization Using Mass Spectrometry And Molecular Dynamics Simulations, Ahmad Kiani Karanji

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mass spectrometry (MS) based-techniques and molecular dynamics (MD) simulations have been used to characterize protein/peptide structure as well as their interactions with lipid vesicles and detergents. Chapter 1 introduces an introduction to the concepts and tools that were used in this work. In Chapter 2, the dominant gas-phase conformer of [M+3H]3+ ions of the model peptide Acetyl-PSSSSKSSSSKSSSSKSSSSK are examined with ion mobility spectrometry (IMS), gas-phase hydrogen deuterium exchange (HDX), and mass spectrometry (MS) techniques. This section furthers the development of a protein structural prediction tool by providing information about gas-phase ion conformers of two model peptides having different solution conformational …


The Effects Of Membrane Physicochemical Properties On Huntingtin Membrane Association And Downstream Aggregation, Maryssa Beasley 2020 West Virginia University

The Effects Of Membrane Physicochemical Properties On Huntingtin Membrane Association And Downstream Aggregation, Maryssa Beasley

Graduate Theses, Dissertations, and Problem Reports (ETD)

Huntington’s Disease (HD) is a fatal neurodegenerative disorder caused by an expanded glutamine repeat region (polyQ) within the huntingtin protein (htt). As a result of the expanded polyQ domain, htt associates into a variety of toxic aggregate species. The polyQ domain of htt is flanked at the N-terminal end by 17 amino acids (Nt17) that adopt an amphipathic α-helical structure in the presence of binding partners such as lipid membranes. In addition to comprising a lipid binding domain, the Nt17 amphipathic α -helix has been directly implicated in htt aggregation initiation via self-association with other Nt17 α -helices. Due to …


Effects Of Nutrient Overload And Environmental Conditions On Algal Bloom Formation: A Case Study Of Water Sources In Eastern Kentucky, Lauren Sutton 2020 Eastern Kentucky University

Effects Of Nutrient Overload And Environmental Conditions On Algal Bloom Formation: A Case Study Of Water Sources In Eastern Kentucky, Lauren Sutton

Online Theses and Dissertations

Eastern Kentucky is home to many private ponds used for agricultural and recreational purposes. Each year, the owners of these ponds observe harmful algal blooms (HABs) that release toxins into the water, potentially limiting the use of these ponds. A pilot study in summer 2018 observed a harmful algal bloom (HAB) occurring in one pond in Madison Country that roughly correlated with a rise in water sulfate levels with no detectable levels of nitrate or phosphate present. A follow-up study of this pond and others in the area was conducted during Summer 2019. The purpose of this project was three-fold: …


Development Of Novel Analytical Methods For Detection And Determination Of Tamoxifen In Oral Fluid And Discrimination Between Regioisomeric Aromatase Inhibitors For Doping Control Purposes, Brooke A. Sutton 2020 Eastern Kentucky University

Development Of Novel Analytical Methods For Detection And Determination Of Tamoxifen In Oral Fluid And Discrimination Between Regioisomeric Aromatase Inhibitors For Doping Control Purposes, Brooke A. Sutton

Online Theses and Dissertations

The use of SERMs (Selective Estrogen Receptor Modulators) – most notably the drug Tamoxifen – has significantly increased among athletes over the past decade to enhance athletic performance and/or negate certain side effects of using anabolic steroids. This “doping” is always banned by WADA (World Anti-Doping Agency) for all athletes, but SERMs can naturally increase testosterone production so they are a tempting alternative to using steroids or androgenic supplements that can cause significant health problems (e.g. acne, breast development, frequent urge to urinate, low libido, etc.). Similarly, the use of AIs (Aromatase Inhibitors) has also increased among athletes for identical …


Development Of A Method For The Detection And Quantification Of Various Benzodiazepines And Z-Drugs In Human Blood And Qualitative Identification In Urine Samples Using Liquid Chromatography Mass Spectrometry (Lc-Ms/Ms), Haley Michel 2020 The University of Akron

Development Of A Method For The Detection And Quantification Of Various Benzodiazepines And Z-Drugs In Human Blood And Qualitative Identification In Urine Samples Using Liquid Chromatography Mass Spectrometry (Lc-Ms/Ms), Haley Michel

Williams Honors College, Honors Research Projects

This method developed in the toxicology department at the Cuyahoga County Medical Examiner’s Office (CCMEO) detects 40 benzodiazepines and metabolites along with several z-drugs in blood and urine by liquid chromatography tandem mass spectrometry. A sample amount of 0.5 mL was used to detect analytes in postmortem drug facilitated sexual assault and impaired driving cases. Twenty-nine analytes met criteria for quantification while the remaining 14 were used as qualitative indicators. Bias and precision results for quality controls met criteria, staying within ±15% except for clonazolam and etizolam which were within ±20%. Quantitative reporting criteria which included dilution integrity was met …


Surface Modification Of Silicon Nanowire Based Field Effect Transistors With Stimuli Responsive Polymer Brushes For Biosensing Applications, Stephanie Klinghammer, Sebastian Rauch, Sebastian Pregl, Petra Uhlmann, Larysa Baraban, Gianaurelio Cuniberti 2020 Institute for Materials Science and Max Bergmann Center of Biomaterials

Surface Modification Of Silicon Nanowire Based Field Effect Transistors With Stimuli Responsive Polymer Brushes For Biosensing Applications, Stephanie Klinghammer, Sebastian Rauch, Sebastian Pregl, Petra Uhlmann, Larysa Baraban, Gianaurelio Cuniberti

Department of Chemistry: Faculty Publications

We demonstrate the functionalization of silicon nanowire based field effect transistors (SiNW FETs) FETs with stimuli-responsive polymer brushes of poly(N-isopropylacrylamide) (PNIPAAM) and poly(acrylic acid) (PAA). Surface functionalization was confirmed by atomic force microscopy, contact angle measurements, and verified electrically using a silicon nanowire based field effect transistor sensor device. For thermo-responsive PNIPAAM, the physicochemical properties (i.e., a reversible phase transition, wettability) were induced by crossing the lower critical solution temperature (LCST) of about 32 ◦C. Taking advantage of this property, osteosarcomic SaoS-2 cells were cultured on PNIPAAM-modified sensors at temperatures above the LCST, and completely detached by simply cooling. Next, …


A Luminescence-Based System For Identification Of Genetically Encodable Inhibitors Of Protein Aggregation, Travis J. Nelson, Shuo Liang, Cliff I. Stains 2020 University of Nebraska - Lincoln

A Luminescence-Based System For Identification Of Genetically Encodable Inhibitors Of Protein Aggregation, Travis J. Nelson, Shuo Liang, Cliff I. Stains

Department of Chemistry: Faculty Publications

Molecules that disrupt protein aggregation represent potential tool compounds for the investigation of numerous human disease states. However, the identification of small molecules capable of disrupting protein aggregation has proven challenging. Larger biomolecules such as antibodies and proteins are promising alternatives due to their increased size. Despite the promise of protein-based inhibitors, generalizable assays are needed to more readily identify proteins capable of inhibiting aggregation. Herein, we utilize our previously reported self- assembling NanoLuc luciferase fragments to engineer a platform in which both detection reagents are expressed from the same plasmid, enabling facile co-transformation with a genetically encodable inhibitor. This …


Domain Wall Conduction In Calcium-Modified Lead Titanate For Polarization Tunable Photovoltaic Devices, Chong-Xin Qian, Hong-Jian Hong-Jian, Qiang Zhang, Jiawei He, Zi-Xuan Chen, Ming-Zi Wang, Xiao Cheng Zeng 2020 Northwest University, Xi’an

Domain Wall Conduction In Calcium-Modified Lead Titanate For Polarization Tunable Photovoltaic Devices, Chong-Xin Qian, Hong-Jian Hong-Jian, Qiang Zhang, Jiawei He, Zi-Xuan Chen, Ming-Zi Wang, Xiao Cheng Zeng

Department of Chemistry: Faculty Publications

Ferroelectric domain wall (DW) conduction, confirmed in recent experiments, has attracted intense attention due to its promising applications in optoelec- tronic devices. Herein, we provide theoretical evidence of electric conduction in Pb0.8Ca0.2TiO3 (PCT) DWs. The separation of charge accumulation in DWs, corresponding to the electronic conduction-band minimum (CBM) and valence-band maximum (VBM), weakens the tendency for the electron-hole recombination, thereby providing more efficient channels for charge transfer. We fabricate PCT-based functional photovoltaic devices with polarization tunable charge transfer to exploit the combined conduction and ferroelectric properties of the DW. The photovoltaic performance of the devices can be regu- lated by …


Determination Of Samarium And Dysprosium Solubility, Seana Brennan 2020 Wilfrid Laurier University

Determination Of Samarium And Dysprosium Solubility, Seana Brennan

Theses and Dissertations (Comprehensive)

In recent years, the use of Rare Earth Elements (REE) has rapidly increased, resulting in numerous potential anthropogenic inputs to the environment. As a result, these metals are emerging as microcontaminants and pose a potential threat to aquatic life. However, the toxicity of REE are largely unknown due, in part, to the limited information on their chemical speciation. The purpose of this project was to gain an understanding of REE precipitate formation and solubility as the foundation for the development of the chemical equilibrium component of toxicity prediction models. Solubility experiments were conducted with Samarium, (Sm), a light REE, and …


Fabrication And Characterization Of Multicomponent Gradients Containing Weakly Acidic And Basic Functional Groups, Kallol Roy 2020 Virginia Commonwealth University

Fabrication And Characterization Of Multicomponent Gradients Containing Weakly Acidic And Basic Functional Groups, Kallol Roy

Theses and Dissertations

Multicomponent synthetic chemical gradients containing amine (NH2) and carboxylic acid (COOH) groups have been prepared on the silanol (Si-OH) containing a base-layer substrate by the controlled-rate infusion (CRI) method. The spatial variation of weakly acidic COOH and basic NH2 functional groups on weakly acidic Si-OH surface was created in such a way that the two antagonist groups at high concentrations were in close proximity (aligned gradient) and were separated (opposed gradient). The difference in concentration of different components (acid, base, or silanol) along the length of aligned or opposed resulted in significantly different physicochemical properties …


Detection Of Biomolecules Via Ocp Measurements Using Npg Electrodes, Borkat Ullah 2020 Virginia Commonwealth University

Detection Of Biomolecules Via Ocp Measurements Using Npg Electrodes, Borkat Ullah

Theses and Dissertations

In sensing application nanoporous gold (NPG) has attracted much attention. NPG is prepared by dealloying Au:Ag alloys. Characterization was done using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV). In this work, the open circuit potential (OCP) of ferricyanide, cysteine, uric acid, and ascorbic acid was measured in phosphate buffer solution (PBS) and biofouling solution containing bovine serum albumin (BSA) at pH 7.4. OCP measurement has been hindered due to biofouling and surface passivation on the metal electrodes. By the use of the NPG electrodes, electrochemical activity can be maintained. From the OCP measurement of cysteine, …


Solid Phase Extraction And High-Precision Mass Spectrometry Analysis Methods For Crassostrea Virginica Metabolome, Alyssa Darling 2020 Virginia Commonwealth University

Solid Phase Extraction And High-Precision Mass Spectrometry Analysis Methods For Crassostrea Virginica Metabolome, Alyssa Darling

Theses and Dissertations

Metabolomics is the rapidly-growing field which focuses on the endpoints of biological processes, and has the capability to provide a snapshot of an organisms’ interaction with their environment on a molecular scale. The objective of the experiment herein was to develop a standard metabolic extraction technique coupled with ultrahigh-precision analytical tools to build a global metabolic pathway of the keystone species Crassostrea virginica. To achieve this, C. virginica whole-body samples were extracted using acetonitrile and methanol, then split into a dehydrated group and a diluted group. Following reversed-phase solid phase extraction (RP-SPE) of both groups, metabolites were identified using …


Derivatization Of Stable, Soluble Redox-Active Organic Materials For Non-Aqueous Redox Flow Batteries, Thilini Malsha Suduwella 2020 University of Kentucky

Derivatization Of Stable, Soluble Redox-Active Organic Materials For Non-Aqueous Redox Flow Batteries, Thilini Malsha Suduwella

Theses and Dissertations--Chemistry

In screening active materials for redox flow batteries (RFBs) – in which solubility is important to raise the volumetric energy density – scientists are slave to trial and error, modifying organic molecules in an attempt to optimize (increase) solubility without compromising other important properties such as stability and redox potential. A trained chemist can often predict the trends of solubility with the structural modifications in the neutral state of the materials, but when it’s come to the charged state of the materials, it doesn’t follow the same trend as the neutral species and relative values are hard to predict. The …


Applications Of Drones In Atmospheric Chemistry, Travis J. Schuyler 2020 University of Kentucky

Applications Of Drones In Atmospheric Chemistry, Travis J. Schuyler

Theses and Dissertations--Chemistry

The emission of greenhouse gases (GHGs) has changed the composition of the atmosphere during the Anthropocene. A major technical and scientific challenge is quantifying the resulting fugitive trace gas fluxes under variable meteorological conditions. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating contributions of different processes to radiative forcing. Therefore, the adverse environmental and health effects of undetected gas leaks motivates new methods of detecting, characterizing, and quantifying plumes of fugitive trace gases. Currently, there is no mobile platform able to quantify trace gases at altitudes(UASs), or drones, can be deployed on-site in …


Flavodoxin, The Hydrogen Atom Of Flavoproteins: A 19f Nmr Study Of Dynamics And Conformational Changes Utilizing Flavodoxin From Rhodopseudomonas Palustris, Taylor Varner 2020 University of Kentucky

Flavodoxin, The Hydrogen Atom Of Flavoproteins: A 19f Nmr Study Of Dynamics And Conformational Changes Utilizing Flavodoxin From Rhodopseudomonas Palustris, Taylor Varner

Theses and Dissertations--Chemistry

Flavodoxin is a small, highly stable protein that contain a single FMN cofactor used to transfer single electrons at low potentials. The organism Rhodopseudomonas palustris contains a long-chain flavodoxin. Long-chain flavodoxins are characterized by a 20 amino acid loop that is proposed to allow interactions with partner proteins. We plan to utilize this protein as a model to build our repertoire with protein fluorination and fluorine NMR in flavoproteins. This tool kit will then be applied to the study of a partner protein of interest that is capable of performing electron bifurcation. We have incorporated m-fluoro tyrosine into flavodoxin and …


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