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Ismar / Rmcmr 2017 Abstract Book - Joint Conference Of The International Society Of Magnetic Resonance, The Rocky Mountain Conference On Epr, And The Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Abstracts from the 59th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, hosted jointly with the International Society of Magnetic Resonance and the Rocky Mountain Conference on EPR. Held in Quebec City, Canada, July 23-28, 2017.

Improved Characterization And Analysis Strategies For Uv-Lif Bioaerosol Instrumentation: Lab And Field Application, Nicole Justine Savage

Electronic Theses and Dissertations

Atmospheric particles of biological origin, also referred to as bioaerosols or primary biological aerosol particles (PBAP), are important to various human health and environmental systems. There has been a recent steep increase in the frequency of published studies utilizing commercial instrumentation based on ultraviolet laser/light-induced fluorescence (UV-LIF), such as the WIBS (wideband integrated bioaerosol sensor), for bioaerosol detection both outdoors and in the built environment. Significant work over several decades supported the development of these technologies, but efforts to systematically characterize the operation of new commercial sensors has remained lacking. Specifically, there are gaps in the understanding of how different …

Quantification Of Airborne Fungal Spores Comparing Molecular Tracers Via Ion Chromatography And Uv-Lif Methods, Marie Ila Gosselin

Electronic Theses and Dissertations

Fungal spores represent an understudied subcategory of bioaerosols that can impact human health as pathogenic and allergenic particles. Fungal spores also have been shown to act as effective ice nuclei and giant cloud condensation nuclei in some cases. This has implications on the hydrological cycle on local and regional scales by impacting the formation and evolution of clouds and precipitation. The quantification of fungal spores has been limited in the past due to methods that were costly and that suffered from poor time resolution. The most commonly applied methods for airborne fungal spore analysis have traditionally included microscopy and culturing, …

Mechanistic Insights Into The Radical S-Adenosyl L-Methionine Enzyme Mftc, Bulat Khaliullin

Electronic Theses and Dissertations

Mycofactocin is a putative peptide-derived redox cofactor in Mycobacterium family. Its putative biosynthetic pathway is encoded by the operon mftABCDEF. The initial step of this pathway is a posttranslational modification of a peptide precursor MftA, which is catalyzed by MftC enzyme. This modification only occurs in the presence of chaperone MftB. Here, we demonstrate that MftC is a radical S-adenosyl L-methionine (SAM) enzyme and we examine its catalytic mechanism. We show that the modification of MftA requires two equivalents of SAM and is implemented in two steps: (i) the decarboxylation of a C-terminal tyrosine, resulting in formation of an …

Sequential Growth Of Molecular Complexity Via Alternating Ground State And Photochemical Reactions, Haibo Li

Electronic Theses and Dissertations

A new strategy of increasing molecular complexity by post photochemical oxidation followed by secondary intramolecular photochemical reaction is developed. It is based on the mild oxidation of photochemical generated alcohol by primary intramolecular cycloaddition of aromatic o-aminoaldehydes and a secondary intramolecular cycloaddition of aromatic o-aminoketone. Both cycloadditions are triggered via excited-state intramolecular proton transfer (ESIPT). Additionally, an efficient continuous reaction of photocatalyzed 2-nitrobenzyl alcohol intramolecular reduction and aryl nitroso Diels-Alder (NDA) reaction was discovered.

Repeat Fuel Specific Emission Measurements On Two California Heavy-Duty Truck Fleets, Molly J. Haugen, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

The University of Denver repeated its 2013 fuel specific gaseous and particle emission measurements on two California heavy-duty vehicle fleets. In 2015 1,457 measurements at the Port of Los Angeles and 694 measurements at the Cottonwood weigh station in northern California were collected. The Port fleet changed little since 2013, increasing the average age (+1.8 years), accompanied by an increase in particle mass (PM) by +266% (0.03 ± 0.01 to 0.11 ± 0.01 gPM/kg of fuel) and black carbon (BC) by +300% (0.02 ± 0.003 to 0.08 ± 0.01 gBC/kg of fuel). Particle number (PN) also increased (1.5 x 10 …

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2016, Gary A. Bishop, Molly J. Haugen

Fuel Efficiency Automobile Test Publications

No abstract provided.

United States Light And Heavy -Duty Fuel Specific On -Road No And No X Emission Factor Trends And Their Importance In Inventory Calculations (Presentation), Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

58th Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 58th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Breckenridge, Colorado, July 17-21, 2016.

C-Reactive Protein Interactions With Cellular Membranes And Supported Lipid Bilayers, Aml Abd Alhamed Alnaas

Electronic Theses and Dissertations

C-reactive protein (CRP) is a serum protein that binds to damaged membranes and initiates the complement immune response. Different forms of CRP are thought to alter how the body responds to inflammation and the degradation of foreign material. Despite knowing that a modified form of CRP(mCRP) binds to downstream protein binding partners better than the native pentameric form, the role of CRP conformation on lipid binding is yet unknown. In this work, three main assays were performed to characterize how conformation affects CRP-membrane interactions. The first assay utilized supported lipid bilayers that mimic the plasma membrane of apoptotic cells. The …

Source Apportionment Of Atmospheric Particulate Matter In Developing Countries Using Trace Elements And Stable Metal Isotope Ratios, Nitika Dewan

Electronic Theses and Dissertations

The work presented herein details the source apportionment of atmospheric particulate matter in developing countries (Kyrgyzstan in Central Asia, metropolitan cities in Northern India, and Shenzhen in China) using trace elements and stable metal isotope ratios. The first study focused on the development of a novel method for the concomitant separation of rare-earth elements in environmental samples of any geological origin. The separation procedure is based on three extraction chromatographic materials, referred to as Sr.Spec, TRU.Spec, and Ln.Spec. This triple column arrangement enables the simultaneous isolation of pure Sr and Nd fractions in less than one day and with great …

Relaxation Of Metals And Their Impact On Nitroxides, Priyanka Aggarwal

Electronic Theses and Dissertations

Pulsed and continuous wave electron spin resonance were used to characterize the relaxation rates of selected paramagnetic metals at 5 to 15 K or 80 K, measure the impact of these rapidly relaxing metals on the relaxation rates of nitroxide radicals in glassy mixtures and in discrete complexes, and characterize novel iron-sulfur proteins.

Spin echoes were observed at 5 to 7 K in 1:1 water:glycerol for Er(diethylenetriamine pentaacetic acid)^2- (Er(DTPA)^2-), Co(DTPA)^3- and aquo Co²⁺ with relaxation times that are strongly temperature dependent. Deep proton modulation was present on spin echo decays (Ch. 3). For Gd …

Quinolines: Novel Synthesis And Derivatives Of Heterocyclic Bioactive Agents, Ginelle A. Ramann

Electronic Theses and Dissertations

Tuberculosis is a pulmonary disease that has ravaged the world throughout history. Even today, many developed and developing countries are experiencing this plight, made worse by the scourge of antibiotic-resistant bacteria.

Mycobacterium tuberculosis's class II fructose-1,6-bisphosphate aldolase presents an interesting target in the design of new therapies against this disease. Previous attempts to construct an inhibitor to this enzyme fell short due to poor selectivity or poor cellular uptake. However a new class of noncompetitive inhibitor based on 8-hydoxyquinoline-2-carboxylic acid presents a fresh approach. Preliminary studies indicate various modifications to this scaffold could be beneficial to its inhibitory efficacy.

Modifications …

Development Of Palladium Catalyzed Alkene Difunctionalization On Vinyl-Quinoline Type Substrate And Isolation Of Pd-Alkyl Intermediate, Lusha Xu

Electronic Theses and Dissertations

The synthesis of quinoline derivatives is a continuing issue facing organic chemists in both academia and industry. To address this problem, palladium-catalyzed alkene difunctionalization was developed to be a powerful and straightforward strategy of synthetic transformations for adding diversity to organic molecules. In this thesis, Pd-catalyzed olefin difunctionalization reactions of vinyl-quinoline type substrate via generating Pd-alkyl intermediates were mainly described. The reactions described herein are pursuing three significant goals: 1) to isolate and recrystallize Pd-alkyl complexes; 2) to achieve oxidation reactions on Pd-alkyl intermediate; and 3) to investigate stereochemistry of nucleopalladation step on vinyl-quinoline starting materials.

Photoassisted Generation Of Complex N, O, S Polyheterocycles, Weston James Umstead

Electronic Theses and Dissertations

This research set out to continue the exploration and diversification of excited state o-azaxylylene cycloadditions, utilizing both pre-photochemical and post-photochemical modifications.

Pre-photochemical modifications came through the addition of heteroatoms, namely nitrogen and oxygen, to the tether that links the unsaturated photopendant to the photogenerated o-azaxylylene. Photochemistry resulted in the formation of new, interesting N, O, S polyheterocycles.

Post-photochemical modifications took place through several different cycloaddition reactions, including a [4+2] hetero-Diels Alder reaction, a [4+2] Povarov cyclization, a [3+2] nitrile oxide addition, and a [3+2] nitrone cyclization. These reactions were applied first to a model system, and then to …

On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2015, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Measuring Real-World Emissions From The On-Road Passenger Fleet, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

Donald H. Stedman 50 Years Of Air Quality Instrument Inventions And Measurements (Presentation), Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

High-Mileage Light-Duty Fleet Vehicle Emissions: Their Potentially Overlooked Importance, Gary A. Bishop, Donald H. Stedman, Daniel A. Burgard, Oscar Atkinson

Fuel Efficiency Automobile Test Publications

No abstract provided.

57th Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 57th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Snowbird, Utah, July 26-31, 2015.

On-Road Heavy-Duty Vehicle Emissions Monitoring System, Gary A. Bishop, Rachel Hottor-Raguindin, Donald H. Stedman, Peter Mcclintock, Ed Theobald, Jeremy D. Johnson, Doh-Won Lee, Josias Zietsman, Chandan Misra

Fuel Efficiency Automobile Test Publications

The introduction of particulate and oxides of nitrogen (NO_x) after-treatment controls on heavy-duty vehicles has spurred the need for fleet emissions data to monitor their reliability and effectiveness. The University of Denver has developed a new method for rapidly measuring heavy-duty vehicles for gaseous and particulate fuel specific emissions. The method was recently used to collect 3,088 measurements at a Port of Los Angeles location and a weigh station on I-5 in northern California. The weigh station NO_x emissions for 2014 models are 73% lower than 2010 models (3.8 vs. 13.9 gNO_x/kg of fuel) and …

Rapid Scan Electron Paramagnetic Resonance (Epr) And Digital Epr Development, Zhelin Yu

Electronic Theses and Dissertations

Rapid scan electron paramagnetic resonance (EPR) was developed in the Eaton laboratory at the University of Denver. Applications of rapid scan to wider spectra, such as for immobilized nitroxides, spin-labeled proteins, irradiated tooth and fingernail samples were demonstrated in this dissertation. The scan width has been increased from 55 G to 160 G. The signal to noise (S/N) improvement for slowly tumbling spin-labeled protein samples that is provided by rapid scan EPR will be highly advantageous for biophysical studies. With substantial improvement in S/N by rapid scan, the dose estimation for irradiated tooth enamels became more reliable than …

Measurement Of Particulate Transition Metals And Atmospheric Processing Of Iron, Benton T. Cartledge

Electronic Theses and Dissertations

The work presented herein details the measurement of particle-bound metals in environmental samples with specific interests in iron (Fe) in atmospheric particulate matter. Metals were measured in ambient PM_2.5 to study the effects and contributions of a light rail system on the concentrations of metals in atmospheric particles. Particulate matter samples were collected on board trains, near the tracks, and at an urban background location in Denver, CO. Metals were found to be enriched in particles collected on board the trains more so than at the other locations. Fe speciation was also measured in the soluble fraction of the …

Fluorescent Biological Aerosol Particles In Coastal Canada And The Link To Atmospheric Ice Nuclei, Jixiao Li

Electronic Theses and Dissertations

Bioaerosols are a subgroup of atmospheric aerosols and are often linked to the spread of human, animal and plant diseases. Bioaerosols also may play an indirect effect on environmental processes, including the formation of precipitation and alteration of the global climate through their role as nuclei for cloud droplet formation. Several types of biological organisms (e.g., fungi and bacteria) have been shown to be effective ice nuclei (IN) and cloud condensation nuclei (CCN).

During 21 days in August 2013 we participated in a collaborative international campaign at a rural, coastal site near the village of Ucluelet on the west coast …

New Methods For Measuring Transient Interactions Between Proteins And Curved Membranes, Philip P. Cheney

Electronic Theses and Dissertations

Variations in the physical deformation of the plasma membrane play a significant role in the sorting and behavior of the proteins that occupy it. Determining the interplay between membrane curvature and protein behavior required the development and thorough characterization of a model plasma membrane with well defined and localized regions of curvature. This model system consists of a fluid lipid bilayer that is supported by a dye-loaded polystyrene nanoparticle patterned glass substrate. As the physical deformation of the supported lipid bilayer is essential to our understanding of the behavior of the protein occupying the bilayer, extensive characterization of the structure …

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 …

Regional-Scale Simulations Of Fungal Spore Aerosols Using An Emission Parameterization Adapted To Local Measurements Of Fluorescent Biological Aerosol Particles, Matthias Hummel, Corinna Hoose, M. Gallagher, D. A. Healy, J. Alex Huffman, D. O'Connor, U. Pöschl, C. Pöhlker, N. H. Robinson, M. Schnaiter, J. R. Sodeau, M. Stengel, E. Toprak, H. Vogel

Chemistry and Biochemistry: Faculty Scholarship

Fungal spores as a prominent type of primary biological aerosol particles (PBAP) have been incorporated into the COSMO-ART (Consortium for Small-scale Modelling- Aerosols and Reactive Trace gases) regional atmospheric model. Two literature-based emission rates for fungal spores derived from fungal spore colony counts and chemical tracer measurements were used as a parameterization baseline for this study. A third, new emission parameterization for fluorescent biological aerosol particles (FBAP) was adapted to field measurements from four locations across Europe. FBAP concentrations can be regarded as a lower estimate of total PBAP concentrations. Size distributions of FBAP often show a distinct mode at …

The Micro-Orifice Uniform Deposit Impactor–Droplet Freezing Technique (Moudi-Dft) For Measuring Concentrations Of Ice Nucleating Particles As A Function Of Size: Improvements And Initial Validation, R. H. Mason, C. Chou, C. S. Mccluskey, E. J. T. Levin, C. L. Schiller, T. C. J. Hill, J. Alex Huffman, P. J. Demott, A. K. Bertram

Chemistry and Biochemistry: Faculty Scholarship

The micro-orifice uniform deposit impactor– droplet freezing technique (MOUDI-DFT) combines particle collection by inertial impaction (via the MOUDI) and a microscope-based immersion freezing apparatus (the DFT) to measure atmospheric concentrations of ice nucleating particles (INPs) as a function of size and temperature. In the first part of this study we improved upon this recently introduced technique. Using optical microscopy, we investigated the non-uniformity of MOUDI aerosol deposits at spatial resolutions of 1, 0.25 mm, and for some stages when necessary 0.10 mm. The results from these measurements show that at a spatial resolution of 1mm and less, the concentration of …

Real ‐ World Vehicle Emissions Measurements (Presentation), Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.