Chemistry Commons^™

The Effects Of Molecular Chaperones On Tau Fibril Assembly, Ahmed Omran

Electronic Theses and Dissertations

The accumulation of microtubule-associated protein tau into fibrillar aggregates is the hallmark of Alzheimer’s disease and other neurodegenerative disorders, collectively referred to as tauopathies. Fibrils can propagate from one cell to the next and spread throughout the brain. However, a study shows that only small aggregates can be taken up by cultured neuronal cells. The mechanisms that lead to the breakage of fibrils into smaller fragments remain unknown. In yeast, the AAA+ chaperone HSP104 processes the reactivation of protein aggregates and is responsible for fragmentation of fibrils. This study focused on investigating the effects of molecular chaperones on tau fibrils …

Photogenerated O-Azaxylylenes: Mechanistic Studies And Synthetic Applications, William Cole Cronk

Electronic Theses and Dissertations

This research sets out to build upon excited state o-azaxylylene cycloaddition. The mechanism behind the excitation and cycloaddition process of photogenerated o-azaxylylenes was determined experimentally. Time-correlated single-photon counting, steady-state spectroscopy, triplet quenching experiments, and quantum yield studies provided evidence suggesting that excited state intramolecular proton transfer is followed by intersystem crossing and stepwise addition to the tethered unsaturated pendant.

In keeping with the principles of diversity oriented synthesis, a modular approach was taken to gain access to a diverse array of N,O,S-Polyheterocycles which were modified postphotochemically via Suzuki coupling to yield fused biaryls. Cycloaddition products, outfitted with halogens …

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2014, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Reactive Nitrogen Species Emission Trends In Three Light-/Medium-Duty United States Fleets, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

Repeated, fuel specific, emission measurements in Denver (2005/2013), Los Angeles (2008/2013) and Tulsa (2005/2013) provide long-term trends in on-road reactive nitrogen emissions from three light/medium duty U.S. fleets. Reductions in oxides of nitrogen (NO_x) emissions ranged from 21% in Denver (5.6 ± 1.3 to 4.4 ± 0.2 gNO_x/kg of fuel) to 43% in Tulsa (4.4 ± 0.3 to 2.5 ± 0.1 gNOx/kg of fuel) since 2005 while decreases in fleet ammonia (NH₃) emissions ranged from no change in Denver (0.45 ± 0.09 to 0.44 ± 0.02 gNH₃/kg of fuel) since 2005 to …

Applications Of Epr With An Emphasis On Tau Fibril Structure, Virginia Meyer

Electronic Theses and Dissertations

Substances containing unpaired electrons have been studied by electron paramagnetic resonance (EPR) for nearly 70 years. With continual development and enhancement of EPR techniques, questions have arisen regarding optimum method selection for a given sample based on its properties. In this work, radiation defects, natural lattice defects, solid organic radicals, radicals in solution, and spin-labeled proteins were analyzed using CW, pulse, and rapid scan EPR to compare methods. Studies of solid BDPA, E' in quartz, N_s⁰ in diamond, and a-Si:H, showed that rapid scan could overcome many obstacles presented by other techniques, cementing rapid scan as an effective …

Heavy Duty Truck Emissions (Presentation), Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2013, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

The Recession Of 2008 And Its Impact On Light-Duty Vehicle Emissions In Three Western Us Cities, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

The global economic recession of 2008 - 2010 severely depressed light-duty vehicle sales in the United States. On-road fleets observed with a remote vehicle exhaust sensor in 2013 at three historical sampling locations in Denver, Los Angeles and Tulsa showed large reductions in the fleet fractions of 2009 model year vehicles of 40%, 38% and 35% respectively when compared to prerecession 2007 levels with the light-duty truck category suffering the largest percentage declines. The fleet fraction for these ~5 year old vehicles is normally reserved for vehicles more than twice their age. This resulted in a significant increase in the …

On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2013, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Rsd Basics (Presentation), Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

Colorado Long Term Light-Duty Vehicle On-Road Emission Trends (Presentation), Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Feat Math Ii And A Discussion Of Negative Measurements, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

The Removal Of Pharmaceuticals From Wastewater By Wet-Air Oxidation, Miao Sun

Electronic Theses and Dissertations

The ubiquitous occurrence of pharmaceuticals and personal care products (PPCPs) in aquatic environments has raised concerns about potential adverse effects on aquatic ecology and human health. Certain pharmaceuticals have recently become a major focus of research to better understand the routes and persistence of these compounds once they enter into aquatic system.

In this research, two model compounds were selected to represent pharmaceuticals that have been identified by recent research as being persistent; specifically, these compounds were trimethoprim (TMP, a basic antibiotic) and gemfibrozil (GEM, an acidic lipid regulator). Treatment of synthetic wastewater that contained these drugs was accomplished using …

Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 5, 2012, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Yellowstone Over-Snow Vehicle Emission Tests – 2012, John D. Ray, Gary A. Bishop, Brent G. Schuchmann, Chris Frey, Gurdas Sandhu, Brandon Graver

Fuel Efficiency Automobile Test Publications

No abstract provided.

Emission Trends In Heavy-Duty Trucks In The South Coast Air Basin (Presentation), Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Heavy-Duty Truck Emissions In The South Coast Air Basin Of California, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

California and Federal emissions regulations for 2007 and newer heavy-duty diesel engines require an order of magnitude reduction in particulate matter and oxides of nitrogen spurring the introduction of new aftertreatment systems. Since 2008 four emission measurement campaigns have been conducted at a Port of Los Angeles location and an inland weigh station in the South Coast Air Basin of California. Fuel specific oxides of nitrogen emissions at the Port have decreased 12% since 2010 while infrared opacity (a measure of particulate matter) remained low, showing no diesel particulate filter deterioration. The weigh station truck’s fuel specific oxides of nitrogen …

Plasma Spectroscopic Techniques Applied To Biological And Environmental Matrices, Morgan Steele Schmidt

Electronic Theses and Dissertations

The purpose of this research was to apply the use of direct ablation plasma spectroscopic techniques, including spark-induced breakdown spectroscopy (SIBS) and laser-induced breakdown spectroscopy (LIBS), to a variety of environmental matrices. These were applied to two different analytical problems. SIBS instrumentation was adapted in order to develop a fieldable monitor for the measurement of carbon in soil. SIBS spectra in the 200 nm to 400 nm region of several soils were collected, and the neutral carbon line (247.85 nm) was compared to total carbon concentration determined by standard dry combustion analysis. Additionally, Fe and Si were evaluated in a …

Structural Polymorphism In Tau Filaments: An Implication For Neurodegenerative Diseases, Ayisha Siddiqua

Electronic Theses and Dissertations

Tau filaments are the pathological hallmark of >20 neurodegenerative diseases including Alzheimer's disease, Pick's disease, and progressive supranuclear palsy. In the adult human brain, six isoforms of tau are expressed that differ by presence or absence of the second of the four semiconserved repeats. As a consequence, half of the tau isoforms have three repeats (3R tau), whereas the other half has four repeats (4R tau).

Site-directed spin labeling of recombinant tau in conjunction with electron paramagnetic resonance spectroscopy was used to obtain structural insights into tau filaments. The studies showed that the filaments of 4R tau and 3R tau …

Emission Changes Resulting From The San Pedro Bay, California Ports Truck Retirement Program, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman, Douglas R. Lawson

Fuel Efficiency Automobile Test Publications

Recent US EPA emissions regulations have resulted in lower emissions of particulate matter and oxides of nitrogen from heavy-duty diesel trucks. To accelerate fleet turnover the State of California in 2008 along with the Ports of Los Angeles and Long Beach (San Pedro Bay Ports) in 2006 passed regulations establishing timelines forcing the retirement of older diesel trucks. On-road emissions measurements of heavy-duty diesel trucks were collected over a three-year period, beginning in 2008, at a Port of Los Angeles location and an inland weigh station on the Riverside freeway (CA SR91). At the Port location the mean fleet age …

Multi-Species Remote Sensing Of Vehicle Emissions On Sherman Way In Van Nuys California, Gary A. Bishop, Brent G. Schuchmann, Donald H. Stedman, Douglas R. Lawson

Fuel Efficiency Automobile Test Publications

As part of the 2010 Van Nuys tunnel study, researchers from the University of Denver measured on-road fuel-specific light-duty vehicle emissions from nearly 13,000 vehicles on Sherman Way (0.4 miles west of the tunnel) in Van Nuys, CA with its multi-species FEAT remote sensor a week ahead of the tunnel measurements. The remote sensing mean gram per kilogram carbon monoxide (CO), hydrocarbons (HC), and oxides of nitrogen (NO_x) measurements are 8.9% lower, 41%, and 24% higher than the tunnel measurements respectively. The remote sensing CO/NO_x and HC/NO_x mass ratios are 28% lower and 20% higher than …

Zirconium Mediated One-Pot Synthesis Of Γ-Amino Acids From Carbon Dioxide, Diego A. Pedroza ^, Shizue Mito *

COURI Symposium Abstracts, Summer 2011

No abstract provided.

Fullerene-Based Organized Self-Assembled Photoactive Layer, Marcelo A. Yates ^, Danisha M. Rivera, Luis Echegoyen *

COURI Symposium Abstracts, Summer 2011

No abstract provided.

Endohedral Derivatives For Bulk Heterojunction Organic Photovoltaic Devices, Gustavo Hernandez^, Michael D. Irwin*

COURI Symposium Abstracts, Summer 2011

No abstract provided.

Octaethyl-Nickel-Porphyrin Functionalized Silica For Fullerene Separation, Adriana Rodríguez^, Danisha M. Rivera, Luis Echegoyen*

COURI Symposium Abstracts, Summer 2011

No abstract provided.

Triphenylamine-Fullerene Dyads As Photoactive Layers In Photovoltaic Cells, Luis F. Gardea^, Mahsa Hosseini, Luis A. Echegoyen*

COURI Symposium Abstracts, Summer 2011

No abstract provided.

Synthesis Of The Precursors For A New Covalent Organic Framework With Triangular Shaped Pores, Fernando J. Correa ^, Venkata P. Neti, Luis A. Echegoyen *

COURI Symposium Abstracts, Summer 2011

No abstract provided.

Electronic States In Layered Si/Sio2/Mos2 Nanostructures, Luis Edgardo Luciano^, Domingo Ferrer, Russell R. Chianelli, Manuel Ramos*

COURI Symposium Abstracts, Summer 2011

No abstract provided.

Trypanosoma Cruzi - Derived Sugar Epitopes - Synthesis And Immunology, Erika Y. Monroy^, Roger A. Ashmus, Jamal Khamsi, Andrew Pardo, Nathaniel S. Schocker, Rosa A. Maldonado, Kayla Vasquez, Alexandre F. Marques, Igor C. Almeida, Katja Michael*

COURI Symposium Abstracts, Spring 2011

The protozoan parasite Trypanosoma cruzi is the causative agent of Chagas disease. As of today no effective vaccine has been developed for it. Certain developmental stages of T.cruzi express cell surface oligosaccharides with terminal alpha-galactosyl and rhamnosyl residues, which are believed to be highly immunogenic in humans. The exact structures and sizes of these epitopes are still unknown. Our quest is to shine light on the chemical structures of immunogenic alpha-Gal and alpha-Rha containing mono-, di-, and trisaccharides that are conjugated to a keyhole limpet hemocyanin (KLH) carrier protein through a combination of chemical synthesis and immunological studies. The compounds …

Dna-Inks For 3-D Printing: Dna Composites For The Rapid Prototyping Of Scaffold In Bioengineering Applications, Jimena I. Aguirre^, Ryan B. Wicker, Mireya A. Perez, Juan C. Noveron*, Juan M. Sanchez

COURI Symposium Abstracts, Spring 2011

Rapid-prototyping has become an incredible technique that manufactures three-dimensional objects with intricate complexity down to 8µm of resolution. We are developing materials that can be used by rapid-prototyping instruments to make scaffolds for bioengineering applications. Our molecular design involves the polymerization of a  (vinylbenzyl)trimethyl-ammonium chloride and DNA solution. Upon UV illumination, the composite polymerizes and forms DNA-hybrid materials.  The end result becomes a ductile transparent material with a thin cross-section. The synthesis, characterization and application of rapid prototyping will be described. Scanning Electron Microscopy (SEM), Light Scattering Detector (LDS), Nuclear Magnetic Resonance (NMR), and Infrared Spectroscopy indicate the structure, characteristics, …