Emissions of methane, non-methane hydrocarbons (NMHC), and carbon dioxide (CO2) at 27 natural gas well pads, 11 non-well locations in oil and gas fields, and 7 hydrocarbon-bearing outcrops in eastern Utah between 2013 and 2016 were measured using a dynamic flux chamber (DFC) in effort to answer the following questions: What effect does the development of oil and gas have on the observed air quality (increased ozone, CO2, volatile organic compounds (VOCs), and/or methane emissions) in northeastern Utah? What percentage of these gases is due to natural background emissions, and what percentage is due to oil and gas development in the region? Methane emissions were the focus of this study, but emissions of other compounds were also measured to better understand the sources and characteristics of emissions. Background methane fluxes were all (mg) meter (m)-2 hour (h)-1. Methane emissions from well pad soils were commonly higher closer to the wellhead, though exceptions existed. Methane fluxes from well pad soils ranged from -5.6 to 70,000 mg m-2h-1. Based on analysis of NMHC emissions data, emissions from 68% of the sampled well pad soils were due to leaks of raw natural gas, whereas the remaining emissions were likely from a combination of raw gas leaks, liquid hydrocarbon spills, and/or methanogenic processes. CO2 emissions were higher than methane emissions 92% of the time at well sites, possibly due to CO2 in natural gas, and/or CO2 emitted from bacterial decomposition of soil organic matter and/or fossil hydrocarbons. Total combustible soil gas concentrations were measured at 21 wells. In summer 2015, soil properties were also analyzed to better understand well leakage. Wells categorized as shut-in had the highest average methane fluxes. Measured methane soil emissions were scaled-up for the entire Uinta Basin to estimate the overall emission from well pad soils, and to compare soil emissions with other natural gas-related sources. Producing and shut-in gas wells were estimated to emit 16.1 ± 4.3 and 8.6 ± 3.2 (90% confidence interval) t y-1 (tonne/year) of methane in the Uinta Basin, respectively, which is

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We report a rare case of Wells syndrome in which a 61-year-old Caucasian male presented with three distinct skin lesions including a cutaneous bulla, an erythematous plaque, and a linear streak located on the patient’s left anterior thigh, left dorsal wrist, and left anterior forearm, respectively. Histologic examination revealed diffuse and interstitial eosinophilic infiltrate admixed with lymphocytes and macrophages that predominantly involve the dermis. Nodular aggregates of eosinophils surrounding dermal collagen fibers suggestive of ‘flame figures’ were identified. Luna histochemical stain was used and highlighted the deposition of eosinophilic granules over the collagen bundles confirming the presence of flame figures. Laboratory workup revealed peripheral eosinophilia, but a comprehensive clinical evaluation failed to reveal a systemic disease and ultimately the diagnosis of eosinophilic cellulitis ‘Wells Syndrome’ was rendered. After a short course of immunosuppressive therapy, the patient experienced a complete resolution of the skin lesions on his last follow-up visit several weeks from the initial diagnosis. This case highlights the various clinical forms that Wells syndrome may present with and may serve as a good example for the use of Luna stain as a simple and cost-effective diagnostic tool that can help to arrive at the accurate diagnosis and inform therapy.

The purpose of this study was to determine whether emphasis on aesthetic development appeared to foster educational growth and desirable behavior development to a greater degree than did participation in a traditional-type program.

<p>Asymmetric multiple quantum wells (AMQWs) can provide broad and flat gain spectra. Broadly tunable diode lasers can be realized with AMQW active regions and without the need for antireflection coatings on cleaved facets.</p> <p> This thesis reports the application of AMQW broadly tunable lasers with uncoated facets for Fourier domain and synthesized optical coherence tomography (OCT). A depth resolution of 13 μm in air was obtained with a test bed OCT system that used diffractive optical elements, short external cavities, and AMQW InGaAsP/InP broadly tunable lasers as the light sources for the Fourier domain and the synthesized OCT measurements. The centre wavelengths of the broadly tunable sources were 1550 nm and the tunable ranges were ≤ 117 nm.</p> <p>The features of broad and flat gain spectra of AMQWs also make AMQWs ideal candidates for broad spectral width superluminescent diodes (SLDs). 1300 nm AMQW InGaAsP/InP SLDs were designed and fabricated for application to time domain OCT. For the design of the active region, it was found by simulation of gain and the comparison of two growths that the transition carrier density (TCD) has to be reasonably high to achieve high power SLDs. A transfer matrix method was used to solve for the modes of planar optical waveguides with arbitrary layers and the thicknesses of these layers were optimized with a Marquardt nonlinear fitting method. With the optimization of the optical waveguide and with AMQWs with high TCDs, the output power of SLDs could reach 2 mW with > 90 nm spectral width. It is shown by time domain OCT measurements that the depth resolution of the OCT measurements could reach 7.85 μmin air with double section SLDs.</p> <p>Two dimensional OCT images of a glass cover slip were built with the imageSC function in Matlab™. Image enhancement with blind/not-blind deconvolution was performed based on the measured point spread function (PSF) of the OCT setup. A Richardson-Lucy algorithm was used as the blind deconvolution method and a not-blind version of a Jansson-Van Cittert method was used.</p> / Thesis / Doctor of Philosophy (PhD)

En omfattande multiproxyanalys har utförts på provtagningar från två vattenhål belägna i Skåneregionen i Sverige. Denna mångsidiga analys involverade flera aspekter, inklusive markkemi, entomologi, mikrofossiler och makrofossiler. Resultaten från markkemianalysen avslöjade betydande skillnader mellan de två vattenhålen. Vattenhål 1 uppvisade en högre halt av organiskt material, vilket tyder på högre glödförluster och högre värden av maximal magnetisk susceptibilitet (MS550) och totalfosfat (CitPOI). För att ytterligare karakterisera egenskaperna hos vattenhålen användes även analyserna infrarödspektroskopi (NiR) och röntgenfluorescens (XRF).   Vattenhål 2 visade tecken på att ha fyllts med bosättningsavfall från platsen. Detta stöddes av markkemiresultaten som visade en lägre halt av organiskt material samt närvaron av antropogena material, såsom förkolnade frön, träkol, bränd lera, ben och keramikfragment.   Makrofossilanalysen avslöjade intressanta fynd. I vattenhål 1 hade växter som etternässla (Urtica urens) och kråkklöver (Comarum palustre) deponerats, tillsammans med enstaka exemplar av Thrips major Uzel. I kontrast bestod de förkolnade fröna från vattenhål 2 huvudsakligen av ogräs, inklusive svinmålla (Chenopodium album) och nattskatta (Solanum nigrum). Det fanns även spår av sädeskorn som korn (Hordeum vulgare), samt oidentifierade fragment av sädeskorn. Resultaten från makrofossilanalysen indikerade att materialet från vattenhål 1 härstammar troligtvis från forntida mänskliga aktiviteter, som odling.   Mikrofossilanalysen visade att det inte fanns några kiselalger (diatoméer) i något av vattenhålen. Sammantaget antyder resultaten från multiproxyanalysen att vattenhål 1 hade genomgått minst tre olika faser i sin historia, medan vattenhål 2 hade fyllts med jord och material från en bosättningsliknande plats, vilket gjorde det svårt att entydigt tolka själva vattenhålets historia och funktion.

Hydraulic fracturing has been increasingly used in the USA to economically extract natural gas and oil from newly discovered shale plays. Despite new, more severe, and long term impacts of hydraulic fracturing compared to conventional drilling, regulatory practices are mostly implemented by states that regulate with older regulations that were were written before the widespread use of hydraulic fracturing. This dissertation presents three essays on the economics of hydraulic fracturing. A standard renewable lease in hydraulic fracturing runs for a five-year primary term. The first essay examines the effect of initial contract length on extraction behavior and social costs. It finds that the rate of extraction decreases over time for both, the social planner and the private extractor. In addition, the social planner has a more stable extraction path compared to the private extractor. Holding other things equal, if the social planner seeks to induce a private extractor to leave a higher in situ stock un-extracted, then the optimal contract duration is longer. Simulations illustrate the magnitude of social costs inherent in hydraulic fracturing and non-optimal fixed contract lengths. The second essay investigates the impact of the significantly increased bonding requirements for horizontal wells introduced in West Virginia in December, 2011, on the probability of violation committed by those wells. Results suggest that the increased bonding requirement has reduced the probability of violation by 2.6 to 3.2 percentage points. Moreover, it slightly reduces the number of violations done by horizontal wells. Finally, the third essay explores several aspects of Act-13, introduced on February 14, 2012, by Pennsylvania. This act imposes new fees that are assessed annually for fifteen years, on all unconventional gas wells in Pennsylvania. This chapter explores the impacts of Act-13 on the likelihood of an unconventional well's shut-down, rate of extraction, and probability of violation. Results suggest that wells incurring this increased fee schedule have a significantly higher likelihood (more than three times) of shut-down. Also, Act-13 have reduced the extraction rate, and the probability of violation committed by unconventional wells in Pennsylvania. / Ph. D.

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