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Mexico City has an ongoing air pollution issue that negatively affects its citizens and surroundings with current structural disconnections preventing the city from improving its overall air quality. Thematic methodological analysis reveals current obstacles and barriers, as well as variables contributing to this persistent problem. A historical background reveals current

Mexico City has an ongoing air pollution issue that negatively affects its citizens and surroundings with current structural disconnections preventing the city from improving its overall air quality. Thematic methodological analysis reveals current obstacles and barriers, as well as variables contributing to this persistent problem. A historical background reveals current programs and policies implemented to improve Mexico’s City air quality. Mexico City’s current systems, infrastructure, and policies are inadequate and ineffective. There is a lack of appropriate regulation on other modes of transportation, and the current government system fails to identify how the class disparity in the city and lack of adequate education are contributing to this ongoing problem. Education and adequate public awareness can potentially aid the fight against air pollution in the Metropolitan City.
ContributorsGarcia, Lucero (Author) / Duarte, Marisa E. (Thesis advisor) / Arzubiaga, Angela (Committee member) / Richter, Jennifer (Committee member) / Arizona State University (Publisher)
Created2018
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Description
The Santa Cruz River Basin shared by Northern Sonora and Southern Arizona is one example of transboundary water resources in the borderlands region that accurately portrays the complexities of binational management of common pool resources, such as water. Industrialization fueled by trade liberalization has resulted in migration to and urbanization

The Santa Cruz River Basin shared by Northern Sonora and Southern Arizona is one example of transboundary water resources in the borderlands region that accurately portrays the complexities of binational management of common pool resources, such as water. Industrialization fueled by trade liberalization has resulted in migration to and urbanization along the border, which have created human rights issues with the lack of water and sanitation, groundwater overdraft of the shared aquifers, and contamination of these scarce resources. Effluent from wastewater treatment plants continues to play increasingly important roles in the region, the use of which has been a source of tension between the two countries. Contributing to these tensions are the strains on binational relations created by border militarization and SB 1070. A shift in water management strategies to increase pubic participation within decision-making, increase the flexibility of the water systems, and increase cross-border collaboration is needed to ensure human and ecological sustainability in the Santa Cruz River Basin. By incorporating direct communication and local capacity as per common pool resource theory, recognizing the connections and implications of management actions through socio-ecological systems understanding, and promoting the organic drivers of change through ecologies of agents, just and vigorous futures can be envisioned and advanced.
ContributorsEppehimer, Drew (Author) / Haglund, LaDawn (Thesis advisor) / Richter, Jennifer (Committee member) / Smith, Karen (Committee member) / Arizona State University (Publisher)
Created2015
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Description
Northeastern Arizona has experienced a recent increase in helium extraction activity. This qualitative case study articulates and explores various sociotechnical imaginaries – or, collectively produced social justifications for technological decisions and systems – that inform this new stage of underground helium extraction. Leveraging two years of interviews, document analysis, and

Northeastern Arizona has experienced a recent increase in helium extraction activity. This qualitative case study articulates and explores various sociotechnical imaginaries – or, collectively produced social justifications for technological decisions and systems – that inform this new stage of underground helium extraction. Leveraging two years of interviews, document analysis, and participant observations to understand and interrogate the political and cultural origins of perceptions around helium extraction, I examined how these imaginaries and associated power dynamics influenced communication within and between stakeholder groups. In order to mitigate the power differentials between stakeholder groups, and put these imaginaries in conversation with each other, I led the development of a series of short videos that explain controversial technoscientific concepts from this research. These videos were produced in continuous collaboration with multiple disparate stakeholders, including activists, regulators, and industry members, in order to create a space for a productive conversation and reflection to explore tensions between conflicting points of view between stakeholders. This iterative work used the imaginaries of helium extraction in Arizona to produce a space for collective deliberation that can result in negotiated shared knowledge through brokered dialogue amongst these disparate groups and their competing visions of Arizona’s helium futures.
ContributorsBruhis, Noa (Author) / Jalbert, Kirk (Thesis advisor) / Richter, Jennifer (Thesis advisor) / Williams, Wendy R (Committee member) / Jenkins, Lekelia (Committee member) / Arizona State University (Publisher)
Created2022
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Description
Since its first report in 1976, many outbreaks linked to Legionella have been reported in the world. These outbreaks are a public health concern because of legionellosis, which is found in two forms, Pontiac fever and Legionnaires disease. Legionnaires disease is a type of pneumonia responsible for the majority of

Since its first report in 1976, many outbreaks linked to Legionella have been reported in the world. These outbreaks are a public health concern because of legionellosis, which is found in two forms, Pontiac fever and Legionnaires disease. Legionnaires disease is a type of pneumonia responsible for the majority of the illness in the reported outbreaks of legionellosis. This study consists of an extensive literature review and experimental work on the aerosolization and UV inactivation of E.coli and Legionella under laboratory conditions. The literature review summarizes Legionella general information, occurrence, environmental conditions for its survival, transmission to human, collection and detection methodologies and Legionella disinfection in air and during water treatment processes.

E. coli was used as an surrogate for Legionella in experimentation due to their similar bacterial properties such as size, gram-negative rod-shaped, un-encapsulated and non-spore-forming bacterial cells. The accessibility and non-pathogenicity of E. coli also served as factors for the substitution.

Three methods of bacterial aerosolization were examined, these included an electric spray gun, an air spray gun and a hand-held spray bottle. A set of experiments were performed to examine E. coli aerosolization and transport in the aerosolization chamber (an air tight box) placed in a Biological Safety Cabinet. Spiked sample was sprayed through the opening from one side of the aerosolization chamber using the selected aerosolization methods. The air sampler was placed at the other side to collect 100 L air sample from the aerosolization chamber. A Tryptic Soy Agar plate was placed inside the air sampler to collect and subsequently culture E. coli cells from air. Results showed that the air spray gun has the best capability of aerosolizing bacteria cells under all the conditions examined in this study compared to the other two spray methods. In this study, we provide a practical and efficient method of bacterial aerosolization technique for microbial dispersion in air. The suggested method can be used in future research for microbial dispersion and transmission studies.

A set of experiments were performed to examine UV inactivation of E. coli and Legionella cells in air. Spiked samples were sprayed through the opening from one side of the aerosolization chamber using the air spray gun. A UV-C germicidal lamp inside the Biological Safety Cabinet was turned on after each spray. The air samples were collected as previously described. The application of UV-C for the inactivation of bacterial cells resulted in removing aerosolized E. coli and Legionella cells in air. A 1 log reduction was achieved with 5 seconds UV exposure time while 10 seconds UV exposure resulted in a 2 log bacterial reduction for both bacteria. This study shows the applicability of UV inactivation of pathogenic bacterial cells in air by short UV exposure time. This method may be applicable for the inactivation of Legionella in air ducts by installing germicidal UV lamps for protecting susceptible populations in certain indoor settings such as nursing homes or other community rooms.
ContributorsYao, Wei (Author) / Abbaszadegan, Morteza (Thesis advisor) / Fox, Peter (Committee member) / Alum, Absar (Committee member) / Arizona State University (Publisher)
Created2015