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2020

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Articles 931 - 960 of 1559

Full-Text Articles in Chemistry

Synthesis, Characterization, Dna Binding, Topoisomerase Inhibition, And Apoptosis Induction Studies Of A Novel Cobalt(Iii) Complex With A Thiosemicarbazone Ligand, Stephen J. Beebe, Michael J. Celestine, Jimmie L. Bullock, Shayna Sandhaus, Jessa Faye Arca, Donald M. Cropek, Tekettay A. Ludvig, Sydney R. Foster, Jasmine S. Clark, Floyd A. Beckford, Criszcele M. Tano, Elizabeth A. Tonsel-White, Raj K. Gurung, Courtney E. Stankavich, Yuk Ching Tse-Dinh, William L. Jarrett, Alvin A. Holder Feb 2020

Synthesis, Characterization, Dna Binding, Topoisomerase Inhibition, And Apoptosis Induction Studies Of A Novel Cobalt(Iii) Complex With A Thiosemicarbazone Ligand, Stephen J. Beebe, Michael J. Celestine, Jimmie L. Bullock, Shayna Sandhaus, Jessa Faye Arca, Donald M. Cropek, Tekettay A. Ludvig, Sydney R. Foster, Jasmine S. Clark, Floyd A. Beckford, Criszcele M. Tano, Elizabeth A. Tonsel-White, Raj K. Gurung, Courtney E. Stankavich, Yuk Ching Tse-Dinh, William L. Jarrett, Alvin A. Holder

Faculty Publications

In this study, 9-anthraldehyde-N(4)-methylthiosemicarbazone (MeATSC) 1 and [Co(phen)2(O2CO)]Cl·6H2O 2 (where phen = 1,10-phenanthroline) were synthesized. [Co(phen)2(O2CO)]Cl·6H2O 2 was used to produce anhydrous [Co(phen)2(H2O)2](NO3)3 3. Subsequently, anhydrous [Co(phen)2(H2O)2](NO3)3 3 was reacted with MeATSC 1 to produce [Co(phen)2(MeATSC)](NO3)3·1.5H2O·C2H5OH 4. The ligand, MeATSC 1 and all complexes were characterized by elemental analysis, FT IR, UV–visible, and multinuclear NMR ( …


Plasma Krebs Cycle Intermediates In Nonalcoholic Fatty Liver Disease, Yana Sandlers, Rohan R. Shah, Ryan W. Pearce, Jaividhya Dasarathy, Arthur J. Mccullough, Srinivasan Dasarathy Feb 2020

Plasma Krebs Cycle Intermediates In Nonalcoholic Fatty Liver Disease, Yana Sandlers, Rohan R. Shah, Ryan W. Pearce, Jaividhya Dasarathy, Arthur J. Mccullough, Srinivasan Dasarathy

Chemistry Faculty Publications

Nonalcoholic liver disease (NAFLD) is manifested with a wide spectrum of clinical symptoms and is closely associated with the metabolic syndrome, inflammation, and mitochondrial dysfunction. Although the mechanism of mitochondrial dysfunction in NAFLD is still not fully elucidated, multiple studies have demonstrated evidence of molecular, biochemical, and biophysical mitochondrial abnormalities in NAFLD. Given the association between NAFLD and mitochondrial dysfunction, the aim of this study is to analyze circulating levels of Krebs cycle intermediates in a cohort of NAFLD-affected individuals and matching healthy controls and to correlate our findings with the liver function metrics. Standard serum biochemistry and Krebs cycle …


Study Of Reaction Dynamics Of Protonated/Deprotonated And Radical Cations Of Guanine In Nucleobases And Nucleosides: Singlet Oxygen Oxidation, C8-Water Addition, Cross-Linking With Lysine And Base-Pair Dissociation, Yan Sun Feb 2020

Study Of Reaction Dynamics Of Protonated/Deprotonated And Radical Cations Of Guanine In Nucleobases And Nucleosides: Singlet Oxygen Oxidation, C8-Water Addition, Cross-Linking With Lysine And Base-Pair Dissociation, Yan Sun

Dissertations, Theses, and Capstone Projects

Among the four DNA nucleobases, guanine (G) has the lowest oxidation potential and represents a preferential target for oxidation and ionization. This leads to the formation of guanine radical cation (G•+) in various oxidative environments. Of the biologically relevant oxidants, electronically excited singlet oxygen (1O2) exclusively damages the guanine bases and gives rise to mutagenesis, DNA-protein cross-linking and cellular death. Combining our home-made electrospray ionization (ESI) guided-ion-beam tandem mass spectrometer, with reaction potential surface calculations and kinetics modeling, five projects have been accomplished as described below.

In project 1, the reactions of deuterated water …


Leveraging Antibodies For Positron Emission Tomography And Near-Infrared Fluorescence Imaging Of Cancer, Kimberly C. Fung Feb 2020

Leveraging Antibodies For Positron Emission Tomography And Near-Infrared Fluorescence Imaging Of Cancer, Kimberly C. Fung

Dissertations, Theses, and Capstone Projects

The high specificity and affinity of antibodies make them attractive for developing drugs to diagnose and treat cancer. The overarching goal of this work is to explore the synthesis and use of antibody-based imaging agents in preclinical models of cancer. This work can be described as two-fold. In the first part, we investigated how the use of a glycans-specific bioconjugation strategy affects Fc gamma RI binding and why it results in improved in vivo performance of immunoconjugates. To do so, we used the clinically relevant positron emission tomography (PET) imaging agent, 89Zr-DFO-pertuzumab, in mouse models of human breast cancer. …


Computational Modeling Of Charge And Excitation Energy Transfer Dynamics In Complex Environments, Ning Chen Feb 2020

Computational Modeling Of Charge And Excitation Energy Transfer Dynamics In Complex Environments, Ning Chen

Dissertations, Theses, and Capstone Projects

This thesis describes computational simulations of charge and exciton dynamics and quantum calculations of organic conjugated oligomers. A comprehensive computational study of charge hopping dynamics was conducted for a model of disordered chain of sites coupled to quantum environments. Time-dependent mean square displacement, diffusion constant, and mobility were calculated by three different computational methods for solving the master equation, which validate the accuracy of calculations. Approximate rate kernels were also tested to understand the effects of approximations in representing quantum environments. In addition to the effects of temperature and disorder, different values of the gradient in the site energy were …


The Use Of A Modified Hess’ Cognitive Rigor Matrix To Assess Students’ Depth Of Knowledge In Key Concepts Of Gas Stoichiometry And Chemical Equilibrium, Maria Greene Feb 2020

The Use Of A Modified Hess’ Cognitive Rigor Matrix To Assess Students’ Depth Of Knowledge In Key Concepts Of Gas Stoichiometry And Chemical Equilibrium, Maria Greene

Dissertations, Theses, and Capstone Projects

The research presented as part of this dissertation is a combination of two separate studies conducted to assess and evaluate undergraduate general chemistry students’ understanding and depth of knowledge (DOK) of concepts in gas stoichiometry and chemical equilibrium. The two separate studies were conducted using a modified Hess Cognitive Rigor Matrix (CRM) to analyze students’ responses to multiple-choice questions (MCQ) and their written rationales to their answer choices. The Hess Cognitive Rigor Matrix, which is an incorporation and coordination of both Bloom’s and Webb’s DOK taxonomies, allowed the facilitation of the opportunity to code students’ written responses across the four …


Hydrophobic Fluoropolymer Nano-Coatings: Study Of Anti-Reflective And Anti-Soiling Properties And Applications, Illya Nayshevsky Feb 2020

Hydrophobic Fluoropolymer Nano-Coatings: Study Of Anti-Reflective And Anti-Soiling Properties And Applications, Illya Nayshevsky

Dissertations, Theses, and Capstone Projects

Anti-reflective, anti-soiling and self-cleaning coatings are currently of interest for photovoltaic (PV) cover glass applications due to their potential to increase the amount of light transmitted through the glass and improve efficiency by reducing the number of contaminants bound to the surface of the glass (soiling). Naturally occurring dew is known to exacerbate soiling via cementation of dust on the glass surface. To address these challenges, fluorinated ethylene-propylene (FEP) polymer coatings were formed on solar cover glass using a lamination-peeling technique. This process forms a thin (thick) polymer coating on the glass with a nano-texture that can be controlled by …


Synthesis And Antitumor Activity Of Potentially Tumor Targeting Analogues Of The Tetrahydrofuran Containing Acetogenins, Patricia Gonzalez Periche Feb 2020

Synthesis And Antitumor Activity Of Potentially Tumor Targeting Analogues Of The Tetrahydrofuran Containing Acetogenins, Patricia Gonzalez Periche

Dissertations, Theses, and Capstone Projects

The tetrahydrofuran containing acetogenins (THF-ACGs) are a naturally occurring class of compounds with potent toxicity against a broad range of tumors, including multidrug resistant (MDR) strains. However, the equally high toxicity to normal cells presents a hurdle for their clinical advancement. This study entails synthetic and tumor targeting strategies that are relevant to their therapeutic development.

Chapter 1 presents a review of the synthesis and biological activity of the THF-ACGs. Chapter 2 covers a modular approach for the synthesis of libraries of THF-ACGs. This strategy is illustrated in the synthesis of C-10 epimers of 4-deoxyannonomontacin (4-DAN), one of the more …


Effects Of Molten-Salt Processing Parameters On The Structural And Optical Properties Of Preformed La2zr2o7:Eu3+ Nanoparticles, Mitzy A. Penilla Garcia, Santosh K. Gupta, Yuanbing Mao Feb 2020

Effects Of Molten-Salt Processing Parameters On The Structural And Optical Properties Of Preformed La2zr2o7:Eu3+ Nanoparticles, Mitzy A. Penilla Garcia, Santosh K. Gupta, Yuanbing Mao

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Molten-salt method has been used to synthesize various functional materials, but it has not been employed to adjust the structure, particle size, and properties of preformed particles. To fill the knowledge gap, in this study, we use a molten-salt medium to reprocess preformed La2Zr2O7:5%Eu3+ nanoparticles which were already formed by a molten-salt synthesis (MSS) method. The molten-salt processing is conducted under various conditions in terms of processing time, temperature, and medium. Specifically, within the studied molten-salt processing time (0 h–24 h) at 800°C, 3 h was found to offer the best optical output. In terms of the investigated molten-salt processing …


Ph-Controlled Preferential Binding Of Cucurbit[7]Uril-Coated Iron Oxide Nanoparticles To 6-Mercaptonicotinic Acid For Fluoroscent Detection Of Cadmium Ions In The Solid State, Reem H. Alzard Feb 2020

Ph-Controlled Preferential Binding Of Cucurbit[7]Uril-Coated Iron Oxide Nanoparticles To 6-Mercaptonicotinic Acid For Fluoroscent Detection Of Cadmium Ions In The Solid State, Reem H. Alzard

Chemistry Theses

A host-guest complex of 6-mercaptonicotinic acid (MNA) and cucurbit [7] uril (CB7) was prepared and conjugated to γ-Fe₂O₃ nanoparticles (NPs) to detect toxic cadmium ions in water as a solid-state sensor. The formation of an inclusion host−guest complex with CB7 was confirmed by UV−vis absorption and proton NMR spectroscopy. CB7 preferentially binds the protonated MNA form compared to the neutral form, demonstrated by a binding constant for the protonated form that is four orders of magnitude higher than the neutral form. An increase in the pKa of MNA by 1.2 units was demonstrated after the addition of CB7, …


Unraveling The Intermediate Species Of Co3O4 Hollow Spheres For Co2 Photoreduction By In Situ X-Ray Absorption Spectroscopy, Peilei He, Sizhou Yang, Wenhui Hu, Sungsik Lee, Jier Huang Feb 2020

Unraveling The Intermediate Species Of Co3O4 Hollow Spheres For Co2 Photoreduction By In Situ X-Ray Absorption Spectroscopy, Peilei He, Sizhou Yang, Wenhui Hu, Sungsik Lee, Jier Huang

Chemistry Faculty Research and Publications

Nanostructured hollow materials have emerged as a promising class of materials for energy conversion and storage. In this work, we report a Co3O4 hollow sphere nanostructure that can serve as a CO2 reduction catalyst to form CO with high selectivity upon visible-light illumination in the presence of a [Ru(bpy)3]2+ molecular photosensitizer. Using in situ X-ray absorption spectroscopy, we not only showed that the Co center in the Co3O4 hollow sphere is the active site for CO2 reduction but also identified a key intermediate species, that is, a reduced Co …


Development Of An Electrochemical Immunosensor For Direct Detection Of Acrylamide In Food Samples, Pei Ying Lau Feb 2020

Development Of An Electrochemical Immunosensor For Direct Detection Of Acrylamide In Food Samples, Pei Ying Lau

Student Works (2020-2029)

Acrylamide, a potential carcinogen which is mainly found in plant-based food such as potato chips, French fries, bread, biscuit, coffee and coco, after undergoing heating process at temperature above 120°C. The permissible maximum intake of acrylamide is 2.6 μg kg−1 of body weight per day to prevent cancer risk. Due to its neurotoxicity and carcinogenicity, a rapid detection method for acrylamide is strongly needed in food safety concern. Herein, a sample pre-treatment free electrochemical immunosensor was developed based on a displacement assay. In a displacement assay format, an antibody is initially bound to the surface immobilized hapten (analyte analogue) and …


Investigation On The Potential Of Dried Blood Stain For The Detection Of Amphetamine Type Stimulants By Enhanced Methods Of Liquid Chromatography Tandem-Mass Spectrometry, Ahmad Zubaidi Fathiah Feb 2020

Investigation On The Potential Of Dried Blood Stain For The Detection Of Amphetamine Type Stimulants By Enhanced Methods Of Liquid Chromatography Tandem-Mass Spectrometry, Ahmad Zubaidi Fathiah

Student Works (2020-2029)

The investigation on the potential of dried blood stain for Amphetamine Type Stimulants (ATS) has been divided into four major parts, from which independent conclusions are drawn. The first part is the development and validation of a novel method for the simultaneous determination of the drugs using liquid chromatography with electrospray ionization tandem mass spectrometer (LC-ESI-MS/MS). The method is enhanced from normal Multi-Reaction Mode (MRM) to Multi-Reaction Mode-Enhanced Product Ion Mode- Multi-Reaction Mode 3 (MRM-EPI-MRM3) and tested in whole blood specimens (WBS), dried blood stain (DBS) and urine specimens as well as applied to real forensic cases in Malaysia. The …


Td-Dft Spin-Adiabats With Analytic Nonadiabatic Derivative Couplings, Nicole Bellonzi, Ethan Alguire, Shervin Fatehi, Yihan Shao, Joseph E. Subotnik Jan 2020

Td-Dft Spin-Adiabats With Analytic Nonadiabatic Derivative Couplings, Nicole Bellonzi, Ethan Alguire, Shervin Fatehi, Yihan Shao, Joseph E. Subotnik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

We present an algorithm for efficient calculation of analytic nonadiabatic derivative couplings between spin-adiabatic, time-dependent density functional theory states within the Tamm-Dancoff approximation. Our derivation is based on the direct differentiation of the Kohn-Sham pseudowavefunction using the framework of Ou et al. Our implementation is limited to the case of a system with an even number of electrons in a closed shell ground state, and we validate our algorithm against finite difference at an S1/T2 crossing of benzaldehyde. Through the introduction of a magnetic field spin-coupling operator, we break time-reversal symmetry to generate complex valued nonadiabatic derivative …


Differential Mobility Spectrometry-Mass Spectrometry (Dms-Ms) For Forensic And Nuclear-Forensic Applications, Ifeoluwa Ayodeji Jan 2020

Differential Mobility Spectrometry-Mass Spectrometry (Dms-Ms) For Forensic And Nuclear-Forensic Applications, Ifeoluwa Ayodeji

USF Tampa Graduate Theses and Dissertations

In forensics and nuclear-forensics, the current lab-based analytical technique employed can be laborious, time consuming, and less suitable for in-situ and real time screening. However, it is important to develop fast and fieldable instrumental technique, without a tradeoff for its high throughput, for drug screening and radionuclear analysis. The underlying factors to be considered in the instrument development ranges from: high potency of samples, even at very low concentration; complex nature of samples in the surrounding environment; real-time chemical composition variation; and instrument size, weight and power (SWAP) consideration. Differential mobility spectrometry (DMS), also known as field asymmetric waveform ion …


Physico-Chemical Regularities Of Chromatographic Retention Of Some Derivatives Of The Isoquinoline Series, I. X. Ruziyev, Sh. N. Jurakulov Jan 2020

Physico-Chemical Regularities Of Chromatographic Retention Of Some Derivatives Of The Isoquinoline Series, I. X. Ruziyev, Sh. N. Jurakulov

Scientific Journal of Samarkand University

The chromatographic retention of the derivatives of pyrimidinone and isoquinolinewas studied under conditions of reversed-phase variant of HPLC. The retention factors were determined for various eluent compositions (CH3CN, CH3OH, and H2O). The relationship between the structure, properties and chromatographic retention of isoquinoline derivatives has been investigated


Excited State Lifetimes Of Sulfur-Substituted Dna And Rna Monomers Probed Using The Femtosecond Fluorescence Up-Conversion Technique, Matthew M. Brister, Carlos E. Crespo-Hernández Jan 2020

Excited State Lifetimes Of Sulfur-Substituted Dna And Rna Monomers Probed Using The Femtosecond Fluorescence Up-Conversion Technique, Matthew M. Brister, Carlos E. Crespo-Hernández

Faculty Scholarship

Sulfur-substituted DNA and RNA nucleobase derivatives (a.k.a., thiobases) are an important family of biomolecules. They are used as prodrugs and as chemotherapeutic agents in medical settings, and as photocrosslinker molecules in structural-biology applications. Remarkably, excitation of thiobases with ultraviolet to near-visible light results in the population of long-lived and reactive triplet states on a time scale of hundreds of femtoseconds and with near-unity yields. This efficient nonradiative decay pathway explains the vanishingly small fluorescence yields reported for the thiobases and the scarcity of fluorescence lifetimes in the literature. In this study, we report fluorescence lifetimes for twelve thiobase derivatives, both …


Can Aromaticity Be A Kinetic Trap? Example Of Mechanically Interlocked Aromatic [2-5]Catenanes Built From Cyclo[18]Carbon, Nikita Fedik, Maksim Kulichenko, Dmitriy Steglenko, Alexander I. Boldyrev Jan 2020

Can Aromaticity Be A Kinetic Trap? Example Of Mechanically Interlocked Aromatic [2-5]Catenanes Built From Cyclo[18]Carbon, Nikita Fedik, Maksim Kulichenko, Dmitriy Steglenko, Alexander I. Boldyrev

Chemistry and Biochemistry Faculty Publications

The unusual stability of cyclo[18]carbon arising from its aromaticity might be used to provide the kinetic trapping needed in the design of interlocked systems. The kinetic barrier separating the interlocked rings and the chemically bonded complex is about 30 kcal mol−1. In addition, the rings can slide freely, which is a promising property for the design of molecular gears and motors.


Molecular Composition And Photochemical Lifetimes Of Brown Carbon Chromophores In Biomass Burning Organic Aerosol, Lauren T. Fleming, Peng Lin, James M. Roberts, Vanessa Selimovic, Robert Yokelson, Julia Laskin, Alexander Laskin, Sergey A. Nizkorodov Jan 2020

Molecular Composition And Photochemical Lifetimes Of Brown Carbon Chromophores In Biomass Burning Organic Aerosol, Lauren T. Fleming, Peng Lin, James M. Roberts, Vanessa Selimovic, Robert Yokelson, Julia Laskin, Alexander Laskin, Sergey A. Nizkorodov

Chemistry and Biochemistry Faculty Publications

To better understand the effects of wildfires on air quality and climate, it is important to assess the occurrence of chromophoric compounds in smoke and characterize their optical properties. This study explores the molecular composition of light-absorbing organic aerosol, or brown carbon (BrC), sampled at the Missoula Fire Sciences laboratory as a part of the FIREX Fall 2016 lab intensive. A total of 12 biomass fuels from different plant types were tested, including gymnosperm (coniferous) and angiosperm (flowering) plants and different ecosystem components such as duff, litter, and canopy. Emitted biomass burning organic aerosol (BBOA) particles were collected onto Teflon …


Aromatic Ouroboroi: Heterocycles Involving A Sigma-Donor-Acceptor Bond And 4n+2 Pi-Electrons, Kelling J. Donald, William Tiznado, Rodrigo Baez-Grez, Diego Inostroza Jan 2020

Aromatic Ouroboroi: Heterocycles Involving A Sigma-Donor-Acceptor Bond And 4n+2 Pi-Electrons, Kelling J. Donald, William Tiznado, Rodrigo Baez-Grez, Diego Inostroza

Chemistry Faculty Publications

The aromaticity and dynamics of a set of recently proposed neutral 5- and 6-membered heterocycles that are closed by dative (donor–acceptor) or multi-center s bonds, and have resonance forms with a Hu¨ckel number of p-electrons, are examined. The donors and acceptors in the rings include N, O, and F, and B, Be, and Mg, respectively. The planar geometry of the rings, coupled with evidence from different measures of aromaticity, namely the NICSzz, and NICSpzz components of the conventional nucleus independent chemical shifts (NICS), and ring current strengths (RCS), indicate non-trivial degrees of aromaticity in certain cases, including the cyclic C3B2OH6 …


Aromatic Hydrazide Compounds That Inhibit The Growth Of Mycobacterium Tuberculosis, Ronald Bartzatt, Preeti Sule, Thushara Galbadage, Jeffrey D. Cirillo Jan 2020

Aromatic Hydrazide Compounds That Inhibit The Growth Of Mycobacterium Tuberculosis, Ronald Bartzatt, Preeti Sule, Thushara Galbadage, Jeffrey D. Cirillo

Chemistry Faculty Publications

Aims: To demonstrate the efficacy of aromatic hydrazide compounds to inhibit growth of Mycobacterium tuberculosis.

Study Design: To synthesize tuberculostats and test their antibacterial activity in-vitro.

Place and Duration of Study: University of Nebraska, Durham Science Center, 6001 Dodge Street, Omaha NE 68182, and Texas A&M Health Science Center, Department of Microbial Pathogenesis and Immunology, 8447 State Hwy 47, Medical Research and Education Building, Room #3012, Bryan, TX 7780. From March 2019 to October 2019.

Methodology: Hydrazide functional groups were formed by covalently bonding hydrazine onto a carbonyl carbon that is a substituent of a single aromatic …


Resolving The Puzzle Of Single-Atom Silver Dispersion On Nanosized Γ-Al2o3 Surface For High Catalytic Performance, Fei Wang, Jinzhu Ma, Shaohui Xin, Qiang Wang, Jun Xu, Changbin Zhang, Hong He, Xiao Cheng Zeng Jan 2020

Resolving The Puzzle Of Single-Atom Silver Dispersion On Nanosized Γ-Al2o3 Surface For High Catalytic Performance, Fei Wang, Jinzhu Ma, Shaohui Xin, Qiang Wang, Jun Xu, Changbin Zhang, Hong He, Xiao Cheng Zeng

Department of Chemistry: Faculty Publications

Ag/γ-Al2O3 is widely used for catalyzing various reactions, and its performance depends on the valence state, morphology and dispersion of Ag species. However, detailed anchoring mechanism of Ag species on γ-Al2O3 remains largely unknown. Herein, we reveal that the terminal hydroxyls on γ-Al2O3 are responsible for anchoring Ag species. The abundant terminal hydroxyls existed on nanosized γ-Al2O3 can lead to single-atom silver dispersion, thereby resulting in markedly enhanced performance than the Ag cluster on microsized γ-Al2O3. Density-functional-theory calculations confirm that Ag atom is mainly anchored by the terminal hydroxyls on (100) surface, forming a staple-like local structure with each Ag …


Dominant Negative Effects By Inactive Spa47 Mutants Inhibit T3ss Function And Shigella Virulence, Jamie L. Burgess, Heather B. Case, R. Alan Burgess, Nicholas E. Dickenson Jan 2020

Dominant Negative Effects By Inactive Spa47 Mutants Inhibit T3ss Function And Shigella Virulence, Jamie L. Burgess, Heather B. Case, R. Alan Burgess, Nicholas E. Dickenson

Chemistry and Biochemistry Faculty Publications

Type three secretion systems (T3SS) are complex nano-machines that evolved to inject bacterial effector proteins directly into the cytoplasm of eukaryotic cells. Many high-priority human pathogens rely on one or more T3SSs to cause disease and evade host immune responses, underscoring the need to better understand the mechanisms through which T3SSs function and their role(s) in supporting pathogen virulence. We recently identified the Shigella protein Spa47 as an oligomerization-activated T3SS ATPase that fuels the T3SS and supports overall Shigella virulence. Here, we provide both in vitro and in vivo characterization of Spa47 oligomerization and activation in the presence and absence …


Production Of The Polysaccharide Curdlan By Agrobacterium Species On Processing Coproducts And Plant Lignocellulosic Hydrolysates, Thomas P. West Jan 2020

Production Of The Polysaccharide Curdlan By Agrobacterium Species On Processing Coproducts And Plant Lignocellulosic Hydrolysates, Thomas P. West

Faculty Publications

This review examines the production of the biopolymer curdlan, synthesized by Agrobacterium species(sp.),on processing coproducts and plant ligno cellulosichydrolysates. Curdlanis a-(1 3)-D-glucan that has various food, non-food and biomedical applications. A number of carbon sources support bacterial curdlan production upon depletion of nitrogen in the culture medium. The influence of culture medium pH is critical to the synthesis of curdlan. The biosynthesis of the-(1 3)-D-glucan is likely controlled by a regulatory protein that controls the genes involved in the bacterial production of curdlan. Curdlan overproducer mutant strains have been isolated from Agrobacterium sp. ATCC 31749 and ATCC 31750 by chemical …


A Zinc-Responsive Fluorophore Based On 5’-(P-Hydroxyphenyl)- Pyridylthiazole, Yuichiro Watanabe, Wanna Sungnoi, Andrew O. Sartorio, Matthias Zeller, Alexander Wei Jan 2020

A Zinc-Responsive Fluorophore Based On 5’-(P-Hydroxyphenyl)- Pyridylthiazole, Yuichiro Watanabe, Wanna Sungnoi, Andrew O. Sartorio, Matthias Zeller, Alexander Wei

Department of Chemistry Faculty Publications

The synthesis and photophysical properties of an ion-sensitive fluorescent compound are described, featuring 5′-(p-hydroxyphenyl)pyridylthiazole (HPPT) as a highly emissive fluorophore. Density functional theory (DFT) calculations indicate that HPPT is capable of intramolecular charge transfer (ICT), with further polarization upon complexation with Zn(II). A 4′-picolyloxy–HPPT derivative was prepared and determined to form a 1 : 1 complex with Zn(NO3)2 in acetonitrile, with a Stokes shift of 137 nm (6323 cm−1) and a 67 nm bathochromic shift in emission relative to the neutral ligand, and a fluorescence quantum yield (ΦPL) of 92%. An X-ray crystal structure of the HPPT–Zn(II) complex confirmed a …


Pine Rosin As A Toxic Cannabis Extract Adulterant, Jiries Meehan-Attrash, Robert Strongin Jan 2020

Pine Rosin As A Toxic Cannabis Extract Adulterant, Jiries Meehan-Attrash, Robert Strongin

Chemistry Faculty Publications and Presentations

Pine rosin (colophony) has been identified as a new adulterant in cannabis oil. Its inhalation toxicity poses a significant health concern to users. For example, pine rosin fumes are released during soldering, and have been cited as a causative agent of occupational asthma. Symptoms also include desquamation of bronchial epithelium, which has also been observed in EVALI patients. The sample analyzed herein was acquired from a cannabis industry source, also contains medium chain triglycerides and oleamide, the latter of which is a hypnotic that is commonly found in the synthetic marijuana product Spice, or K2. A combination of NMR and …


Dual-Balance Electrodynamic Trap As A Microanalytical Tool For Identifying Gel Transitions And Viscous Properties Of Levitated Aerosol Particles, David S. Richards, Kristin L. Trobaugh, Josefina Hajek-Herrera, Ryan D. Davis Jan 2020

Dual-Balance Electrodynamic Trap As A Microanalytical Tool For Identifying Gel Transitions And Viscous Properties Of Levitated Aerosol Particles, David S. Richards, Kristin L. Trobaugh, Josefina Hajek-Herrera, Ryan D. Davis

Chemistry Faculty Research

The formation of gelatinous networks within an aerosol particle significantly alters the physicochemical properties of the aerosol material. Existing techniques for studying gel transitions rely on bulk rheometry, which is limited by contact with the sample, or microrheological techniques such as holographic optical tweezers, which rely on expensive equipment and high-powered lasers that can degrade light-absorbing aerosol. Here, we present a new technique to probe the microrheological characteristics of aerosol particles and explore gel formation under atmospheric conditions in a contactless environment without the need for high-power light sources. In a dual-balance quadrupole electrodynamic balance, levitated droplets of opposite polarity …


Author Correction: Closing The Nuclear Fuel Cycle With A Simplified Minor Actinide Lanthanide Separation Process (Alsep) And Additive Manufacturing, Artem V. Gelis, Peter Kozak, Andrew T. Breshears, M. Alex Brown, Cari Launiere, Emily L. Campbell, Gabriel B. Hall, Tatiana G. Levitskaia, Vanessa E. Holfeltz, Gregg J. Lumetta Jan 2020

Author Correction: Closing The Nuclear Fuel Cycle With A Simplified Minor Actinide Lanthanide Separation Process (Alsep) And Additive Manufacturing, Artem V. Gelis, Peter Kozak, Andrew T. Breshears, M. Alex Brown, Cari Launiere, Emily L. Campbell, Gabriel B. Hall, Tatiana G. Levitskaia, Vanessa E. Holfeltz, Gregg J. Lumetta

Chemistry and Biochemistry Faculty Research

No abstract provided.


Methods Of Making And Using Lignin Derivatives, Mark Alan Helle, Chin Li Cheung Jan 2020

Methods Of Making And Using Lignin Derivatives, Mark Alan Helle, Chin Li Cheung

Department of Chemistry: Faculty Publications

Materials and methods for preparing reactive lignin and for preparing a bio-based adhesive are described herein.

This disclosure generally relates to methods of making and using reactive lignin. This disclosure also generally relates to methods of making and using bio-based adhesives. Lignin is the second most abundant natural polymer behind cellulose, yet lignin has very little commercial value despite years of research. Lignin is one of the major components of the cell wall in wood and other plant based materials such as hemp or crop wastes. It is produced in enormous quantities each year, primarily as a by-product in the …


Applications Of Triplet-Photosensitizers And Development Of Photochemical Methods, Luke V. Lutkus Jan 2020

Applications Of Triplet-Photosensitizers And Development Of Photochemical Methods, Luke V. Lutkus

Dissertations and Theses

Photochemistry focuses on various aspects of the interaction of light with molecules. This work entails new methodology for fundamental measurements of photochemistry along with novel applications of triplet-photosensitizers. Herein described are two separate methodologies developed for the determination of the quantum yield. A method for the singlet oxygen quantum yield was developed that utilizes the reaction between singlet oxygen and dimethyl sulfoxide (DMSO) to produce dimethyl sulfone. The rate of the reaction is measured by the pressure decrease that results from the consumption of oxygen from the headspace of a sealed system. It was found that the rate of pressure …