Physical Sciences and Mathematics Commons^™

An Experimental And Computational Evaluation Of The Importance Of Molecular Diffusion In Gas Gravity Currents, Jeremy Jac Herman

Graduate Theses and Dissertations

The accidental release of hazardous, denser-than-air gases during their transport or manufacture is a vital area of study for process safety researchers. This project examines the importance of molecular diffusion on the developing concentration field of a gas gravity current released into a calm environment. Questions which arose from the unexpectedly severe explosion in 2005 at Buncefield, England were of particular interest. The accidental overfilling of a large tank with gasoline on a completely calm morning led to a massive open air explosion. Forensic evidence showed that at the time of ignition, a vapor cloud, most of which now appears …

Consumer Adoption Of Health Information Systems, Sankara Subramanian Srinivasan

Graduate Theses and Dissertations

At nearly 18 percent of the country's GDP, the U.S. healthcare industry continues to wrestle with growing cost and a quality of care that does not match the increased spending. The dominant focus to date has been on promoting Health IT (HIT) system implementation and digitizing health records at the provider's end, with scant attention to the role of the patient in the healthcare process. The source of inefficiency in the healthcare system is not only on account of shortcomings at the provider's end but also due to non-compliance (such as failing to adhere to medication advice and follow-up visits) …

Assessment Of The Predictive Reliability Of A Swat Flow Model And The Evaluation Of Runoff Generation And Bmp Effectiveness In A Shale-Gas Impacted Watershed Using A Modeling Approach, Kwasi Asante

Graduate Theses and Dissertations

In order to ensure a harmonious harness of shale-gas resources while ensuring minimal damage to the environment, it is imperative that studies to conduct to inform various aspects of managing the environment. This includes the development of reliable hydrologic models to inform in decisions concerning water and the environment.

The first objective of this study was to evaluate the predictive reliability of the Soil and Water Assessment Tool (SWAT) model based on respective methods of LULC data classification and data type spatial resolution. Results showed that the high-resolution data classified with object-oriented image method does not provide any significant advantage …

Oxidation Of Dibenzothiophene To Dibenzothiophene Sulfone Using Tungsten (Vi) Oxide, Alejandrina Rivera

Theses and Dissertations - UTB/UTPA

The oxidation of dibenzothiophene (DBT) to dibenzothiophene-sulfone has been considered as an alternate method to remove sulfur from crude oil. This study demonstrates that the oxidative desulfurization (ODS) of DBT to DBT-sulfone occurs using WO3 as a catalyst. WO3 was synthesized and characterized using X-ray diffraction to determine the phase of WO3. Each reaction was refluxed and run for four hours using WO3 as a catalyst, dibenzothiphene, and four different solvents: decahydronapthalene, n-dodecane, decalin, and dodecane. The reactions were performed at temperatures ranging from 120 oC to 150 oC. Aliquots were taken at 30 minutes for up to four hours …

Remediation Of Copper(Ii) And Lead(Ii) From Aqueous Solution Using Engineered Iron Oxide And Manganese Oxide Nanomaterials, Carlos Tamez Jr.

Theses and Dissertations - UTB/UTPA

Nano-sized Fe3O4, Fe2O3, Mn3O4, and MnO2 were synthesized by titration/precipitation and characterized using powder XRD. pH assays determined that optimum binding occurred at pH 4 for Fe3O4 and Fe2O3 and pH 3 for Mn3O4 and MnO2. Maximum adsorption of Cu(II) and Pb(II) occurred within 20 min or less of contact with the nanomaterials. The synthesized nanomaterials showed a binding preference for Pb(II) over Cu(II) at concentrations above 50 ppm. Batch studies also showed no significant reduction in the binding of copper and lead to either Fe3O4, Fe2O3, Mn3O4, or MnO2 in the presence of Na+ , K+ , Mg2+ or …

A Survey Of Heavy Metals In Water, Soil And The Surrounding Plants In The Lower Rio Grande Valley, Erving W. Morelius

Theses and Dissertations - UTB/UTPA

Heavy metal pollution of the environment in recent years has become a major issue of importance for both human and environmental health. Samples were investigated for the potential pollution of the area as it is a vital produce producing area. During the study plant, soil and water samples were collected from the Donna Reservoir and Canal System to test the concentration of various heavy metals. The heavy metals tested included both potentially toxic and micronutrients in the samples which included arsenic, cadmium, chromium, copper, iron, lead, nickel and sulfur. During the study, a sixty day sampling period was used to …

Novel Modulation Of Adenylyl Cyclase Type 2, Jason Michael Conley

Open Access Dissertations

Adenylyl cyclase isoforms are distinctly modulated by G protein subunits and are therefore hypothesized to be uniquely regulated by proteins that influence G protein signaling. Activator of G protein signaling 3 (AGS3) is a G protein modulator that binds Gαi subunits in the GDP-bound state, implicating AGS3 as an important regulatorof Gi-coupled receptor signaling. We studied the ability of AGS3 to modulate recombinant adenylyl cyclase(AC) type 1 and 2 signaling in HEK293 cells following both acute and persistent activation of the D _2Ldopamine receptor (D_2L DR). AGS3 expression modestly enhanced the potency of acute quinpirole-induced D _2LDR …

Evaluation Of Broiler Litter Heat Production During Windrowing & Nitrogen Based Gas Emission Mitigation Using Biofilter, Min Lei

Graduate Theses and Dissertations

Ammonia emission from animal feeding operations (AFOs) has negative effects on environment and animals' health. Thus measuring and mitigating ammonia emission from AFOs is important for environmental protection. In chapter I, different ammonia measurements were discussed and a mitigation technology- biofilter was represented.

In-house windrowing of built-up litter has been used by broiler producers to reduce pathogen loads and rejuvenate litter for the next flock. When litter is piled up for an extended period during downtime, heat generated by the litter pile can become a substantial heat source due to the metabolism of microorganisms. In chapter II, heat production rates …

Understanding User Resistance To Information Technology: Toward A Comprehensive Model In Health Information Technology, Madison N. Ngafeeson

Theses and Dissertations - UTB/UTPA

The successful implementation of health information systems is expected to increase legibility, reduce medical errors, boost the quality of healthcare and shrink costs. Yet, evidence points to the fact that healthcare professionals resist the full use of these systems. Physicians and nurses have been reported to resist the system. Even though resistance to technology has always been identified as key issue in the successful implementation of information technology, the subject remains largely under-theorized and deficient of empirical testing. Only two proposed model have been tested so far. Hence, though user resistance is clearly identified and defined in literature, not very …

Student Motivation For Pursuing A Minor In Environmental Sustainability, Luanne Woods Lewis

Graduate Theses and Dissertations

Environmental sustainability dominates the global conversation seeking to increase awareness and change the culture of thinking concerning the relationship between humans and the Earth. Because many universities offer programs relative to environmental sustainability, a need exists to understand why students pursue these programs. This study examined student motivation for pursuing an environmental sustainability minor in one institution of higher education. Career, learning, monetary, and Social responsibility were the motivational factors considered in this study. The results of this study indicated significant differences among the motivational factors for pursuing a minor in sustainability among those students surveyed. Significant differences existed for …

Litter Conditioning Is Differentially Affected By Leaf Species, Phosphorus Enrichment, And Light Availability, Erin E. Scott

Graduate Theses and Dissertations

Anthropogenic enrichment of nitrogen and phosphorus is one of the most pervasive and detrimental threats to aquatic ecosystems worldwide. In streams that rely on allochthonous basal food resources, such as leaves, nutrient pollution can result in altered food quality and decreased carbon (C) standing stocks. However, the magnitude and mechanisms of this change in quality are poorly understood. Laboratory microcosm studies were conducted to 1) quantify the response of litter C:P to a gradient of phosphorus (P) enrichment (0, 0.05, and 0.5 mg SRP/L) across leaf species with variable levels of degradability (sugar maple and oak), and 2) quantify the …

The Consciousness Of Water: Narrative Flows, Environmental Change, And The Voice Of Yemen, Tricia Nellessen

Graduate Theses and Dissertations

Icebergs are melting in the Arctic. The Gulf of Mexico is warming and producing hurricanes such as Katrina. The delta of the southern United States is drying. And, Yemen will be the first country in modern history to experience a lack of accessible ground water, as soon as 2017 possibly. Yemen's situation has been tracked by scholars and governments since the 1960s. Despite this fact, cities have expanded in Yemen and the population has increased its use of water while little has been invested in desalination or infrastructure to offset growth. Climate change has affected humans for thousands of years; …

Modeling Greenhouse Gas Emissions And Net Return Implications For Cow-Calf Producers In The Ozark Highlands, Stephen Aaron Smith

Graduate Theses and Dissertations

Cow-calf producers in the Ozark Highlands region are under continuous pressure to improve economic efficiency. Additionally, estimating greenhouse gas (GHG) emissions from cow-calf and forage production processes may become increasingly important as policy makers seek to mitigate or reduce agriculture's role in climate change. As such, this analysis had three objectives. Objective 1: Provide a model that could be used by cow-calf producers, extension agents, and researchers to evaluate GHG and net return (NR) repercussions when modifying site characteristics, production methods, and inputs. Objective 2: Develop a user guide such that the methodology for estimating cow-calf GHG emissions and NR …

Fate Of 17Α-Estradiol, 17Β-Estradiol, And Estrone In Agricultural Soils And Sediments, Michael L. Mashtare Jr

Open Access Dissertations

The shift to concentrated animal production facilities and increasing rural-urban migration has increased the localized land application of nearly 1 billion tons of manure and biosolids annually. Although these applications provide nutrients and contribute to soil tilth, they also serve as a source for an estimated 49 tons of the natural manure-borne estrogens, 17α-estradiol (17α-E2), 17β-estradiol (17β-E2), and estrone (E1). While these estrogens are critical to endocrine systems, the low concentrations observed in the environment can disrupt endocrine function in non-target organisms, e.g., altering secondary sex characteristics which can lead to changes in wildlife communities.

Research presented here focuses on …

Developing White Ash With Resistance To The Emerald Ash Borer, Kaitlin Joy Palla

Open Access Theses

Hypocotyls isolated from mature embryos germinated on Murashige and Skoog (MS) medium supplemented with 22.2 µM 6-benzyladenine (BA) and 0.5 µM thidiazuron (TDZ) were transformed using Agrobacterium tumefaciens strain EHA105 harboring the pBI121-8D2 vector containing the neomycin phosphotransferase (nptII) gene and a full length, codon-optimized Bacillus thuringiensis Cry8Da protoxin gene (cry8D2). Explants were transformed in a bacterial suspension with 100 µM acetosyringone using 90 s sonication and 10 min vacuum-infiltration. Four independent lines of transformed shoots were selectively regenerated on MS medium with 22.2 µM BA, 0.5 µM TDZ, 50 mg L^-1 adenine sulfate, 10% …

Sanitation Infrastructure, Medicinal Plant Use And Diarrhea In Rural Costa Rican Communities, Travis Clifford Sondgerath

Open Access Theses

Diarrhea is estimated to be responsible for 3.3 million deaths a year and is particularly problematic in the developing world among children. The Millennium Development Goals established by the United Nations has set a goal of reducing mortality among children by two thirds during the new millennium. However due to the nature of diarrhea it is often difficult to study its patterns, distribution, and determinants.

This study presents an analysis of the relationship between diarrhea and sanitation infrastructure and medicinal plant use in 4 rural Costa Rican communities. Over the past few decades' access to clean drinking water and municipal …

Habitat Restoration Of A Constructed Ohio River Embayment, Caleb Michael Rennaker

Open Access Theses

Backwater habitats of large rivers provide habitat for aquatic biota and influence important predator-prey interactions in fishes and other aquatic organisms. However, these areas often exhibit turbid conditions and lack habitat complexity. Restoration of lentic habitats through direct habitat manipulations has shown success in prior efforts, but these methods have not been tested in backwater habitats of large rivers. I attempted to create habitat in an Ohio River embayment by establishing founder colonies of aquatic macrophytes coupled with the placement of underwater gravel beds. I also evaluated the effects of total suspended solids (TSS) on overwintering structures of American Pondweed …

Content Analysis Concerning State Green Lodging Certification Programs In The United States, Yue Yu

Open Access Theses

The present thesis reports a content analysis study of state green lodging certification programs (SGLCPs) in the United States. The study explores how the government and industry associations operate and maintain SGLCPs. Through online research, the researcher found that 20 states have SGLCP. There are total 21 programs in operation currently. The study focused on the textual content of the 21 programs' websites.

The study determined the rationale of SGLCPs adoption through analyzing program purposes and certification bodies. The application procedure, assessment process, participation rate, certification levels, recertification process of programs were discussed to figure out whether SGLCPs implement the …

Turning Stealth Liposomes Into Cationic Liposomes For Anticancer Drug Delivery, Vijay Gyanani

University of the Pacific Theses and Dissertations

Targeting the anticancer agents selectively to cancer cells is desirable to improve the efficacy and to reduce the side effects of anticancer therapy. Previously reported passive tumor targeting by PEGylated liposomes (stealth liposomes) have resulted in their higher tumor accumulation. However their interaction with cancer cells has been minimal due to the steric hindrance of the PEG coating. This dissertation reports two approaches to enhance the interaction of stealth liposomes with cancer cells. First, we designed a lipid-hydrazone-PEG conjugate that removes the PEG coating at acidic pH as in the tumor interstitium. However, such a conjugate was highly unstable on …