Physical Sciences and Mathematics Commons^™

Ultrafine Black Carbon: A Cumulative Assessment On The Physiology Of Lung - Derived Cells, M Esther Salinas

Open Access Theses & Dissertations

Combustion-derived nanomaterials are noxious ultrafine (<100 nm) aerosolized by-products generated by human activity. They pose threats to pulmonary health due to their small size, allowing them to penetrate deep into the alveolar regions causing detrimental responses downstream. Indeed, an examination between nanocarbon particle exposure and poor pulmonary health via cellular behavior was needed. I hypothesized that low-dose and long-term administrations of carbonaceous nanoparticles contribute to respiratory conditions by irritating lung-derived cells. Responses to ultrafine black carbon (UBC), a key component of airborne pollutants, by human lung A549 and murine lung LA4 epithelial cells, human peripheral-blood monocytes THP1, and murine macrophages RAW264.7 were investigated. These lines were chosen because epithelial cells and mononuclear cells (monocytes and macrophages) are the first to come in contact with inhaled particulate matter (PM) and contribute to stress and inflammation of pulmonary tissues. The cells were first plated on day zero and fed fresh UBC suspended in culture media on days one, four, and seven. The exposure regimen included three different low-level concentrations of UBC. On day ten, all cells were prepared for subsequent assays. Effects on cellular viability revealed that UBC was modestly cytotoxic while ATPase and esterase activity (termed enzyme vitality for the purpose of this study) were significantly diminished in a dose-dependent manner. Additionally, beta-galactosidase proportionally increased with UBC concentration compared to untreated cells, indicating that cellular senescence was promoted across all cell types. Multiple markers of oxidative stress were subsequently measured, showing non-uniform trends and displaying moderate accumulation of oxidative damage, contingent upon cell line and UBC treatment. However, a significant induction of inner mitochondrial membrane depolarization of human UBC-treated cells was observed; an aberrant cell-cycle progression was found across all cells. The implemented regimen of UBC exposure elicited an imbalance of free (reduced) glutathione, altered mitochondrial potential, and abnormal cell-cycle activity. This method demonstrated that modifications across both species induced changes to cellular fitness overall. The data supported that compounding nanosized black carbon exposure could negatively affect overall pulmonary cell health by distinctively modifying intracellular activity. Additionally, we further surmised that sustained exposure to nanocarbon could impair innate immunity. Therefore, reactive oxygen species (ROS), reactive nitrogen species (RNS), and cytokine levels upon continuous administrations to 3.0 μg/mL UBC after brief challenges to microbial proxies were assessed; on day 9, the cells were succumbed to three different microbial insults (LPS, Poly I:C, and Zymosan). On day 10, measurements demonstrated a moderate accumulation of oxidative stress, conditional to each cell type. Thus, UBC plus microbe approach triggered pro-oxidant levels and cytokine production across different cell types and diminished phagocytic response by murine macrophages. Based on the results, ultrafine-PM exposure may impair inflammatory function in response to pathogenic infections. In summation, our findings indicated that additive nanosized UBC in combination with microbe-like challenges may compromise cellular behavior, suggesting potential ways by which inhalation of ultrafine-PM may contribute to or exacerbate poor pulmonary health.

Exploring Paths For Water Services And Human Capabilities In U.S.-Mexico Border Colonias, Chilton Tippin

Open Access Theses & Dissertations

This Thesis examines causes and consequences of water insecurity in colonias on the U.S.-Mexico border and explores potential pathways for improving situations wherein low-income households lack reliable access to water and sewer services. Colonias are low-income, rural and/or semi-rural communities that lack basic services, such as paved streets, water, and sewer. Through in-depth interviews, surveys, and ethnographic observations, the research presented here describes needs, desires, and capabilities of residents in two high-needs Texas colonias. First, findings elucidate the lived experiences of water insecurity in colonias households, leading to an argument that lacking water access constitutes a nexus, wherein water insecurity …

Manfreda Maculosa Leaf Extracts And Their Effects On Whole And Selected Myotoxic Components In Crotalid Venom, Charles Steven Gilbert

Open Access Theses & Dissertations

Manfreda spp have been used for the treatment of snakebite by several cultures in North and Central America (Austin & Honychurch, 2004, Johnson, 1999, Moerman, 2008, Verhoek, 1978a). There has been no systematic study of the genus Manfreda for its usefulness in the treatment of snakebite.

While the annual incidence of snakebite in the United States is relatively low (approximately 8,000 - 10,000), with a low mortality rate of 5 - 6 cases per year, there is still significant morbidity associated with snakebite (CDC - NIOSH, 2018, Springhouse Corp (eds), 2005). Worldwide numbers of the cases of snakebite can only …

Near Room Temperature Magnetocaloric Materials For Magnetic Refrigeration, Eduardo Martinez Teran

Open Access Theses & Dissertations

Magnetic refrigeration (MR) is a cooling process based on the magnetocaloric effect (MCE) that is present to some extent in all magnetic materials, and the ones in which this effect is more appreciable are called magnetocaloric materials (MCM). The implementation of new designs and materials for the construction of cooling systems is a must do, being essential that these improved designs will reduce the environmental impact and increase the efficiency of their predecessors. In this thesis, the magnetocaloric effect theory is presented from a thermodynamic point of view and also the synthesis and study to a new Heusler alloy (MnFe2Ga) …

The Rhetoric Of Low Carbon Energy Technology Scientists And Engineers, Nicolas Cesar Hernandez

Open Access Theses & Dissertations

Scholars in the burgeoning field of Energy Communication have successfully contributed to communication studies and environmental communication practice. However, energy communication scholars have largely focused on energy of media coverage, corporate communication and decision making in the context crisis. While rich and informative, this tendency has left quotidian aspects of energy communication rather understudied. As such, this Thesis contributes to the understanding of the internal, non-untechnical rhetoric of low carbon energy technology (LCET) scientists and engineers (herein LCET professionals). Textual analysis was used to examine LCET professionals' internal rhetoric at professional trade conferences and through long form, semi-structured interviews. Wind …

Investigation Into The Effects Of Copper Based Nanoparticles On Sugarcane (Saccharum Officinarium) And Zucchini (Cucurbita Pepo), Carlos Tamez

Open Access Theses & Dissertations

The widespread use of copper-based nanomaterials has been accompanied by an increasing interest to understand their potential risks. Due to high surface area to volume properties, nanomaterials are more reactive than their bulk counterparts. Copper nanoparticles are used in numerous products, and could enter the environment through their synThesis or incidental use. It is essential to understand the effects of nanoparticles on edible crops by performing both short-term and long-term experiments at relevant exposure concentrations. In order to evaluate biochemical and physiological effects crops, sugarcane and zucchini, were grown in soil amended with: Kocide 3000 (copper-based fungicide), nano-sized CuO (nCuO), …

Potential Of Nanoscale Elements To Control Fusarium Wilt Disease In Tomato (Solanum Lycopersicum), Enhance Macronutrient Use Efficiency, And Increase Its Yield, Ishaq Olarewaju Adisa

Open Access Theses & Dissertations

Nanotechnology has a great potential in ensuring food production, security and safety globally. Over the past decade, research on the use of nanomaterials to supply nutrient elements and protect plants from pest and diseases has significantly increased. Tomato (Solanum lycopersicum) is one of the most consumed vegetables in the world and United State is one of its largest producers globally generating billions of dollars annually in revenue.. Tomato plants are affected worldwide by Fusarium wilt caused by Fusarium oxysporum f. sp. Lycopersici. There is growing concern about excessive use of conventional pesticides in controlling Fusarium and other diseases in tomato …

Creating Spaces For Conversations On Conservation: A Case Study Of Joint Forest Management In East Sikkim, India., Paulami Banerjee

Open Access Theses & Dissertations

Successful community-based natural resource management should include both resource professionals and local communities. Recognizing this fact, my research seeks to encourage more locally adaptive and collaborative forest governance that facilitates sustainable development by enabling grassroots participation. Specifically, I explore opportunities for developing a more sustainable relationship between India's Joint Forest Management (JFM) program and rural forest-dependent communities in Sikkim-a remote, northeastern state of India bordering Nepal to the west, the Tibet Autonomous region of China to the north and northeast, and Bhutan to the southeast. As an instrument for sustainable forestry management, JFM seeks to develop partnerships between forest user …

Urban Water Demand In Arid-Regions: Modeling And Forecasting Climatic And Economic Effects, Tallen Ashley Capt

Open Access Theses & Dissertations

Water demand is an ever-growing concern for many municipalities around the world and understanding the driving forces of demand is critical to ensure sustainability. The goal of this research was to develop mechanistic models of urban water demand that could be used as decision support tools for regional water managers. This Dissertation research focused on modeling water consumption in El Paso, Texas at the daily and annual time scale for use in a long-term forecast. The Dissertation is divided into three major chapters: the first two chapters describe independent models on (1) meteorological and (2) economic effects, respectively. The third …

Mesacs: A Multi-Method Environmental Study Over The Arctic Chukchi Sea, Julio Eduardo Ceniceros

Open Access Theses & Dissertations

The Arctic environment is a dynamic part of Earth’s natural system and is currently undergoing rapid increasing air temperature and decreasing sea ice extent, leading to more open ocean waters. As open water areas become more prevalent, phytoplankton communities near the surface of the ocean can proliferate earlier in the year and are apt to reach higher concentrations by the end of the summer season. Phytoplankton biomass around the world has been known to produce a microscopic biofilm at the surface of the ocean composed of biogenic and biological particles which then become airborne and work as both cloud condensation …

Strategies To Improve The Electrochemical Of Performance Transition Metal Compounds As Anode Materials For Li-Ion Batteries, Noemi Dominguez

Open Access Theses & Dissertations

Nowadays, our society depends on fossil fuels as the main energy source. However, depletion, price fluctuations, and other concerns, such as global warming, have led to an exhaustive research for renewable energy resources. Here is where electrochemical energy systems play a critical role since they can provide power when renewable energy is not available. Among these electrochemical energy storage systems Li-ion batteries (LIBs) have shown higher volumetric, gravimetric, and power density capacities over other battery systems.

However, commercial LIBs are still relying on graphite base materials for the anode. However, graphite possesses a low specific capacity. Recently, transition metal compounds …

The Illusion Of An Abundant End- A Phenomenological Approach To Sustainability: The Progress Trap And The Transformative Potential Of Dialogue, Shantanu Rojatkar

Open Access Theses & Dissertations

Abundance is a concept according to which a thing is deemed to be in plenty. The feeling of satisfaction and assurance, arising from something that is concretely abundant, serves as a material reason for motivation of a desired action. Just like the stock of food lying in our fridge, ensuring more than just the needs of the moment, the abundance cooks the taste of freedom, freedom from worrying about tomorrow. However, over consumption out of greed as a potential outcome of abundance, could result in the increased capacity of a person in order to reach the initial level of satisfaction. …

A Study Of Solvent Effects On The Ground And Excited States Of Endohedral Tri-Scandium Nitride C80 Fullerene Coupled With Zinc Phthalocyanine And Metal-Free Phthalocyanine Using Dft-Pcm Method, Timilsina Prasad Timlsina

Open Access Theses & Dissertations

The photovoltaic active materials composed of endohedral metafullerene and phthalocyanine derivatives are known as excellent electron donor-acceptor pairs. The tri-metallic nitride endohedral C80 fullerene exhibits high absorption coefficients in the visible region of the spectrum and has similar electron-accepting abilities as that of C60 fullerene, which can allow for higher efficiencies in OPV devices. In this study, we examine the effect of solvent on the charge transfer excitation energies of Sc3N@C80-ZnPc and Sc3N@C80-H2Pc donor-acceptor molecular complexes. Three different solvents with different polarity - water, toluene, and acetone are used. The solvent is modeled as a polarizable continuum as implemented in …

Energy Efficiency And Fatigue Failure On Gears And Bearings For Processing Rebar Steel, Jesus Gabriel Garcia

Open Access Theses & Dissertations

Steel industry is a major emitter of air pollutants, a leading industrial consumer of water, a minor source of contaminated liquids, a massive producer of solid waste, and a significant source of CO2. The objective on this thesis work is to minimize the greenhouse gas emissions when processing steel. Gears and bearings were evaluated based on their performance when exposed to cyclic stresses. The importance for having a proper set up on rolling mills to increase efficiency for processing rebar steel has been detailed on paper. In contrast, mechanical vibration has been measured on gears and bearings to determine efficiency …

Fishers' Ecological Knowledge And Stable Isotope Analysis: A Social-Ecological Systems Approach To Endangered Species Conservation, Kathryn Rose Wedemeyer-Strombel

Open Access Theses & Dissertations

Identifying developmental habitat is essential for understanding population structure and species resiliency, especially for critically endangered species. In long-lived, oceanic, migratory animals such as sea turtles, elucidating developmental grounds is particularly difficult. When data are deficient or challenging to acquire, scientists often lean towards traditional quantitative methods when a social-ecological systems approach could better provide crucial baseline data and guiding information. Fishers’ ecological knowledge (FEK), the combination of experiential and culturally transmitted knowledge, is expert knowledge and should be treated as such. In 2008, FEK led to the “rediscovery” of the critically endangered eastern Pacific (EP) population of hawksbill sea …

A Coupled Modeling Framework For Allocation Design In Land-Use And Land-Cover Changes To Optimize Biofuel Feedstock Production, Ana C. Cram

Open Access Theses & Dissertations

Environmental awareness has increased the demand for renewable energy. Notably, the production of biofuels from feedstock is gaining interest as a viable measure to reduce fossil fuels consumption. Nevertheless, it is crucial to identify the trade-offs between bioenergy crop cultivation and the environmental impact on land, water, and atmosphere.

Intensifying biofuel cultivation trigger effects associated with Land Use and Land-use-change, which are complex to assess. While hydrological models had been used to investigate the environmental impacts of land-use changes on water and soil quality, their quantitative assessment is often incomplete. Changes in land use and agricultural activities also contribute to …

A Quantitative Assessment Of Trace Metals In Subsurface Soils And Groundwater In Agricultural Fields Of El Paso, Texas, Emmanuel Sosa

Open Access Theses & Dissertations

Intensive agricultural practices such as irrigation, application of pesticides and the use of fertilizers, as well as contamination from urban settings and industrial activities contribute to the input of trace metals onto soils and groundwater. Consequentially, biological uptake and accumulation concentrate these toxic metals in fruits, vegetables, and grains that will be used for human consumption. In southern New Mexico and western Texas, cropland is developed along the Rio Grande valley. These farmers are concerned about the quality of their irrigation water and soils in order to produce adequate crops and maintain healthy soils to maximize revenue. To evaluate loading …

Stratigraphic And Structural Characterization And Evolution Of Exposed Megaflaps Flanking Salt Diapirs, Cora Evelyn Gannaway Dalton

Open Access Theses & Dissertations

A Neoproterozoic salt system exposed in the Willouran Ranges of South Australia and a Mesozoic salt system in the south-central Pyrenees of Spain provide natural laboratories to investigate the stratigraphic and structural development of megaflaps flanking salt diapirs. Megaflaps are near-vertical to overturned, deep minibasin stratal panels that extend far up the flanks of steep diapirs or their equivalent welds. Megaflaps can form by halokinetic drape-folding, contraction, or a combination of these processes. The existing models of megaflap development are based primarily on seismic data, well penetrations, cross-section restorations, and numerical and analog modeling. Investigation of the sedimentology, stratigraphy, and …

Deciduous Shrub Encroachment Effects On Tundra Soil Properties, Daniela Aguirre

Open Access Theses & Dissertations

Deciduous shrub abundance is increasing in tundra ecosystems as an effect of rising temperatures which may change tundra physical properties and, in turn, microbial communities and biogeochemical processes. Two mechanisms through which shrub presence may affect tundra ecosystems were examined in this study; the physical presence of the shrubs and effects of increasing shrub litter inputs. In a sub-arctic alpine tundra ecosystem, dominated by the deciduous shrub Betula glandulosa, both shrub presence (shrub present and removed) and litter quantity (no litter/litter removed, ambient litter, and twice ambient litter) were manipulated; multiple ecosystem properties where measured within the treatment plots over …