ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.
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Description
This dissertation explores the use of bench-scale batch microcosms in remedial design of contaminated aquifers, presents an alternative methodology for conducting such treatability studies, and - from technical, economical, and social perspectives - examines real-world application of this new technology. In situ bioremediation (ISB) is an effective remedial approach for many contaminated groundwater sites. However, site-specific variability necessitates the performance of small-scale treatability studies prior to full-scale implementation. The most common methodology is the batch microcosm, whose potential limitations and suitable technical alternatives are explored in this thesis. In a critical literature review, I discuss how continuous-flow conditions stimulate microbial attachment and biofilm formation, and identify unique microbiological phenomena largely absent in batch bottles, yet potentially relevant to contaminant fate. Following up on this theoretical evaluation, I experimentally produce pyrosequencing data and perform beta diversity analysis to demonstrate that batch and continuous-flow (column) microcosms foster distinctly different microbial communities. Next, I introduce the In Situ Microcosm Array (ISMA), which took approximately two years to design, develop, build and iteratively improve. The ISMA can be deployed down-hole in groundwater monitoring wells of contaminated aquifers for the purpose of autonomously conducting multiple parallel continuous-flow treatability experiments. The ISMA stores all sample generated in the course of each experiment, thereby preventing the release of chemicals into the environment. Detailed results are presented from an ISMA demonstration evaluating ISB for the treatment of hexavalent chromium and trichloroethene. In a technical and economical comparison to batch microcosms, I demonstrate the ISMA is both effective in informing remedial design decisions and cost-competitive. Finally, I report on a participatory technology assessment (pTA) workshop attended by diverse stakeholders of the Phoenix 52nd Street Superfund Site evaluating the ISMA's ability for addressing a real-world problem. In addition to receiving valuable feedback on perceived ISMA limitations, I conclude from the workshop that pTA can facilitate mutual learning even among entrenched stakeholders. In summary, my doctoral research (i) pinpointed limitations of current remedial design approaches, (ii) produced a novel alternative approach, and (iii) demonstrated the technical, economical and social value of this novel remedial design tool, i.e., the In Situ Microcosm Array technology.
ContributorsKalinowski, Tomasz (Author) / Halden, Rolf U. (Thesis advisor) / Johnson, Paul C (Committee member) / Krajmalnik-Brown, Rosa (Committee member) / Bennett, Ira (Committee member) / Arizona State University (Publisher)
Created2013
Description
In the last years of the twentieth century, while the narrative of women in other Latin American countries has received critical attention, Bolivian women's narrative has been widely ignored. The fact that the voice of Bolivian women in Latin American feminist discourse is rarely discussed in Latin American criticism is enough to justify the present study. This work focuses on three prominent Bolivian writers: Gaby Vallejos, Giovanna Rivero Santa Cruz, and Erika Bruzonic. The short stories of these three authors are characterized by accentuating certain telluric features revealed in the background of their feminine/feminist narratives. At the same time, based on the American and European feminist literary critique, this work analyzes the feminine/feminist themes mounted in the narrative of these authors. Gaby Vallejos, with a cinematic style, chronicles the life and customs of the "valluno" context, building a mosaic of different voices in dialogue. Her topics revolve around binaries: life-death, and pain and pleasure, voicing condemnation for a patriarchal society. Ericka Bruzonic deals with women and identity, memory and the breaking of lineage as an imposing structure. Her themes are built around the cosmopolitism of "paceña" urban life, and her voice transgresses the binomials established by a patriarchal society. Finally Giovanna Rivero Santa Cruz takes the life and customs of the Santa Cruz and the Guarani culture and her plots weave these elements reaching for myths and taboos, involving the reader into her stories. In this manner, her narrative makes an incursion into the conscious and unconscious realm of the readers questioning their wealth of moral and social values, their notions of heterosexuality, and sexual taboos. The three writers, with different narrative styles yet dialogical, narrate various experiences of women from different regions, social classes, ages, education, and sexual orientations. Our authors give high value to the word and the body embedded in the culture, thereby affirming their woman's voice as Bolivians and their literary presence in the context of Latin American literature.
ContributorsLopez, Norma (Author) / Urioste-Ascorra, Carmen (Thesis advisor) / Tompkins, Cynthia (Committee member) / Rosales, Jesus (Committee member) / Arizona State University (Publisher)
Created2013
Description
Reductive dechlorination by members of the bacterial genus Dehalococcoides is a common and cost-effective avenue for in situ bioremediation of sites contaminated with the chlorinated solvents, trichloroethene (TCE) and perchloroethene (PCE). The overarching goal of my research was to address some of the challenges associated with bioremediation timeframes by improving the rates of reductive dechlorination and the growth of Dehalococcoides in mixed communities. Biostimulation of contaminated sites or microcosms with electron donor fails to consistently promote dechlorination of PCE/TCE beyond cis-dichloroethene (cis-DCE), even when the presence of Dehalococcoides is confirmed. Supported by data from microcosm experiments, I showed that the stalling at cis-DCE is due a H2 competition in which components of the soil or sediment serve as electron acceptors for competing microorganisms. However, once competition was minimized by providing selective enrichment techniques, I illustrated how to obtain both fast rates and high-density Dehalococcoides using three distinct enrichment cultures. Having achieved a heightened awareness of the fierce competition for electron donor, I then identified bicarbonate (HCO3-) as a potential H2 sink for reductive dechlorination. HCO3- is the natural buffer in groundwater but also the electron acceptor for hydrogenotrophic methanogens and homoacetogens, two microbial groups commonly encountered with Dehalococcoides. By testing a range of concentrations in batch experiments, I showed that methanogens are favored at low HCO3 and homoacetogens at high HCO3-. The high HCO3- concentrations increased the H2 demand which negatively affected the rates and extent of dechlorination. By applying the gained knowledge on microbial community management, I ran the first successful continuous stirred-tank reactor (CSTR) at a 3-d hydraulic retention time for cultivation of dechlorinating cultures. I demonstrated that using carefully selected conditions in a CSTR, cultivation of Dehalococcoides at short retention times is feasible, resulting in robust cultures capable of fast dechlorination. Lastly, I provide a systematic insight into the effect of high ammonia on communities involved in dechlorination of chloroethenes. This work documents the potential use of landfill leachate as a substrate for dechlorination and an increased tolerance of Dehalococcoides to high ammonia concentrations (2 g L-1 NH4+-N) without loss of the ability to dechlorinate TCE to ethene.
ContributorsDelgado, Anca Georgiana (Author) / Krajmalnik-Brown, Rosa (Thesis advisor) / Cadillo-Quiroz, Hinsby (Committee member) / Halden, Rolf U. (Committee member) / Rittmann, Bruce E. (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2013
Community-based development: scaling up the correct use of misoprostol at home births in Afghanistan
Description
Globally, more than 350 000 women die annually from complications during pregnancy and childbirth (UNFPA, 2011). Nearly 99% of these, according to World Health Organization (WHO) trends (2010) occur in the developing world outside of a hospital setting with limited resources including emergency care (WHO, 2012; UNFPA, 2011). The most prevalent cause of death is postpartum hemorrhage (PPH), accounting for 25% of deaths according to WHO statistics (2012). Conditions in Afghanistan are reflective of the scope and magnitude of the problem. In Afghanistan, maternal mortality is thought to be among the highest in the world. The Afghan Mortality Survey (AMS) data implies that one Afghan woman dies about every 2 hours from pregnancy-related causes (AMS, 2010). Lack of empowerment, education and access to health care resources increase a woman's risk of dying during pregnancy (AMS, 2010). This project aims to investigate the prospects of scaling-up the correct use of misoprostol, a prostaglandin E1 analogue, to treat PPH in developing countries where skilled assistance and resources are scant. As there has been little published on the lessons learned from programs already in place, this study is experience-driven, based on the knowledge of industry experts. This study employs a concurrent triangulation approach to synthesize quantitative data obtained from previous studies with qualitative information gathered through the testimonies of key personnel who participated in pilot programs involving misoprostol. There are many obstacles to scaling-up training initiatives in Afghanistan and other low-resource areas. The analysis concludes that the most crucial factors for scaling-up community-based programs include: more studies analyzing lessons learns from community driven approaches; stronger partnerships with community health care workers; overcoming barriers like association with abortion, misuse and product issues; and a heightened global and community awareness of the severity of PPH without treatment. These results have implications for those who actively work in Afghanistan to promote maternal health and other countries that may use Afghanistan's work as a blueprint for reducing maternal mortality through community-based approaches. Keywords: Afghanistan, community-based interventions, community-driven, maternal mortality, MDG5, misoprostol, postpartum hemorrhage, reproduction, scale-up
ContributorsCristy, Candice (Author) / Grossman, Gary (Thesis advisor) / Parmentier, Mary-Jane (Committee member) / Byrd, Denise (Committee member) / Arizona State University (Publisher)
Created2013
Description
Synechocystis sp PCC 6803 is a photosynthetic cyanobacterium that can be easily transformed to produce molecules of interest; this has increased Synechocystis’ popularity as a clean energy platform. Synechocystis has been shown to produce and excrete molecules such as fatty acids, isoprene, etc. after appropriate genetic modification. Challenges faced for large–scale growth of modified Synechocystis include abiotic stress, microbial contamination and high processing costs of product and cell material. Research reported in this dissertation contributes to solutions to these challenges. First, abiotic stress was addressed by overexpression of the heat shock protein ClpB1. In contrast to the wild type, the ClpB1 overexpression mutant (Slr1641+) tolerated rapid temperature changes, but no difference was found between the strains when temperature shifts were slower. Combination of ClpB1 overexpression with DnaK2 overexpression (Slr1641+/Sll0170+) further increased thermotolerance. Next, we used a Synechocystis strain that carries an introduced isoprene synthase gene (IspS+) and that therefore produces isoprene. We attempted to increase isoprene yields by overexpression of key enzymes in the methyl erythritol phosphate (MEP) pathway that leads to synthesis of the isoprene precursor. Isoprene production was not increased greatly by MEP pathway induction, likely because of limitations in the affinity of the isoprene synthase for the substrate. Finally, two extraction principles, two–phase liquid extraction (e.g., with an organic and aqueous phase) and solid–liquid extraction (e.g., with a resin) were tested. Two–phase liquid extraction is suitable for separating isoprene but not fatty acids from the culture medium. Fatty acid removal required acidification or surfactant addition, which affected biocompatibility. Therefore, improvements of both the organism and product–harvesting methods can contribute to enhancing the potential of cyanobacteria as solar–powered biocatalysts for the production of petroleum substitutes.
ContributorsGonzalez Esquer, Cesar Raul (Author) / Vermaas, Willem (Thesis advisor) / Chandler, Douglas (Committee member) / Bingham, Scott (Committee member) / Nielsen, David (Committee member) / Arizona State University (Publisher)
Created2013
Description
This dissertation integrates humanities with social science methodologies within a critical framework, seeking to explore the relationship between the neoliberal restructuring and the intersection of gender, class and heteronormativity in contemporary China. In this project, neoliberalism is conceptualized as an art of governance centering on the intersection of race, gender, class and sexuality to create market subjects and sustain market competition. Focusing on China's recent socio-economic and cultural upheavals, this dissertation tries to address these questions: 1. How have class inequalities, binaristic gender and heteronormative discourses been employed intersectionally by the Chinese state to facilitate China's social transformation? 2. How has this process been justified and consolidated through the intersection of gender, class, sexuality and race? 3. How do the marginalized groups respond to these material and cultural practices? Building on the discursive analysis of China's televised 60th anniversary ceremony and If You Are the One, a popular Chinese reality show, as well as the data from the interview, focus group and participant observation of more than 100 informants, it is found that the intersection of gender, class and heteronormativity is central to China's neoliberal transition. A group of flexible and cheap laborers have been disarticulated and rearticulated from the population as the voluntary servitude to China's marketization and re-integration with the global economy. New controlling images, such as the bourgeois nucleus family, are created to legitimize this process. However, these disparate material and discursive practices have entailed contradictions and conflicts within the intersectional biopolitical system, and created contingent spaces of ungovernability for the marginalized groups. Building on these discursive analyses and empirical data, I reconceptualize intersectionality as a multi-dimensional-and-directional network to regulate and manage power for social organization and regulation, which grounds the biopolitical basics for the neoliberal economy. Thus I argue that we need to engage with the dynamics between the intersectional biopolitical structure and people's emerging experiences to construct a grounded utopia alternative to the neoliberal dominance for substantive social changes.
ContributorsZhang, Charlie Yi (Author) / Quan, H. L. T. (Thesis advisor) / Fonow, Mary Margaret (Thesis advisor) / Martinez, Jacqueline M. (Committee member) / Lee, Charles T. (Committee member) / Arizona State University (Publisher)
Created2013
Description
The purpose of my dissertation project is to understand how Same-Gender Loving (SGL) Black Christian men negotiate their sexuality and spirituality in spaces that are not always accepting of SGL people, by examining on how Black SGL men perform their sexual identities within hegemonic institutions that often deny their existence or outwardly seek to exclude them from their communities. I have identified three scripts that Black SGL men often follow within Black religious settings. The first script that SGL people often follow in the church is that of deliverance-- confessing their same-gender desires and maintaining that they have been delivered from those desires The second is "don't ask don't tell" performed by men who many believe and suspect of being SGL; so long as they do not publicly affirm these beliefs they are able to hold a variety of positions in their religious communities.. The last script involves accepting one's same-gender desires and also affirming one's Christian beliefs, proclaiming that the two are not at odds with one another. I examine how these scripts and/or others are performed by and on the bodies of Black SGL males in two distinct sites. The first is the career and music of former gospel star Anthony Charles Williams II (Tonex / B. Slade), who has utilized the three scripts at various times in his career. The next site is that of theatre, where I explore how these scripts have been employed in dramatic texts. By reading Christian Black SGL performance through its theological parameters, I aim to discern the avenues in which Black people in the United States are able to perform same-gender sexual identities in spaces that are constructed as "homophobic," and in so doing combat the narrative of hyper-homophobia in Black communities.
ContributorsChester, Tabitha Jamie Mary (Author) / Anderson, Lisa (Thesis advisor) / Leong, Karen J (Committee member) / Honegger, Gitta (Committee member) / Arizona State University (Publisher)
Created2013
Description
Human activity has increased loading of reactive nitrogen (N) in the environment, with important and often deleterious impacts on biodiversity, climate, and human health. Since the fate of N in the ecosystem is mainly controlled by microorganisms, understanding the factors that shape microbial communities becomes relevant and urgent. In arid land soils, these microbial communities and factors are not well understood. I aimed to study the role of N cycling microbes, such as the ammonia-oxidizing bacteria (AOB), the recently discovered ammonia-oxidizing archaea (AOA), and various fungal groups, in soils of arid lands. I also tested if niche differentiation among microbial populations is a driver of differential biogeochemical outcomes. I found that N cycling microbial communities in arid lands are structured by environmental factors to a stronger degree than what is generally observed in mesic systems. For example, in biological soil crusts, temperature selected for AOA in warmer deserts and for AOB in colder deserts. Land-use change also affects niche differentiation, with fungi being the major agents of N2O production in natural arid lands, whereas emissions could be attributed to bacteria in mesic urban lawns. By contrast, NO3- production in the native desert and managed soils was mainly controlled by autotrophic microbes (i.e., AOB and AOA) rather than by heterotrophic fungi. I could also determine that AOA surprisingly responded positively to inorganic N availability in both short (one month) and long-term (seven years) experimental manipulations in an arid land soil, while environmental N enrichment in other ecosystem types is known to favor AOB over AOA. This work improves our predictions of ecosystem response to anthropogenic N increase and shows that paradigms derived from mesic systems are not always applicable to arid lands. My dissertation also highlights the unique ecology of ammonia oxidizers and draws attention to the importance of N cycling in desert soils.
ContributorsMarusenko, Yevgeniy (Author) / Hall, Sharon J (Thesis advisor) / Garcia-Pichel, Ferran (Thesis advisor) / Mclain, Jean E (Committee member) / Schwartz, Egbert (Committee member) / Arizona State University (Publisher)
Created2013
Description
This study was done in collaboration with the Kino Border Initiative. The Kino Border Initiative is a Catholic, bi-national organization run by Missionary Sisters of the Eucharist, Jesuit priests and lay people. The organization is dedicated to providing services to recently deported migrants and migrants-in-transit through their soup kitchen, women's shelter and first aid station in Nogales, Sonora. Based on their experiences in the women's shelter, the Missionary Sisters of the Eucharist and researcher sought out to further understand migrant women's experiences of gender-based violence prior to migration. Using data collected by the Sisters, it was decided to use an analysis rooted in testimonio, and, in this way, use the women's words as a foundational basis for understanding the migration of women. The analysis is based on 62 testimonies related to women's histories of violence and their migration experiences, and the information from 74 intake questionnaires that were all analyzed retroactively. The analysis of data and testimonios has led to the realization that violence suffered by migrant women is not limited to the journey itself, and that 71% of women report having suffered some sort of violence either prior to or during migration. Often times, the first experiences of violence originated in their homes when they were children and continue to repeat itself throughout their lifetimes in varied forms. Their stories reveal how the decision to migrate is a consequence to the transnational and structural violence that pushes women to seek out ways to survive and provide for their families.
ContributorsConrad, Marla (Author) / Elenes, C. Alejandra (Thesis advisor) / Simmons, William P. (Committee member) / Téllez, Michelle (Committee member) / Arizona State University (Publisher)
Created2013
Description
Microbial electrochemical cells (MXCs) are promising platforms for bioenergy production from renewable resources. In these systems, specialized anode-respiring bacteria (ARB) deliver electrons from oxidation of organic substrates to the anode of an MXC. While much progress has been made in understanding the microbiology, physiology, and electrochemistry of well-studied model ARB such as Geobacter and Shewanella, tremendous potential exists for MXCs as microbiological platforms for exploring novel ARB. This dissertation introduces approaches for selective enrichment and characterization of phototrophic, halophilic, and alkaliphilic ARB. An enrichment scheme based on manipulation of poised anode potential, light, and nutrient availability led to current generation that responded negatively to light. Analysis of phototrophically enriched communities suggested essential roles for green sulfur bacteria and halophilic ARB in electricity generation. Reconstruction of light-responsive current generation could be successfully achieved using cocultures of anode-respiring Geobacter and phototrophic Chlorobium isolated from the MXC enrichments. Experiments lacking exogenously supplied organic electron donors indicated that Geobacter could produce a measurable current from stored photosynthate in the dark. Community analysis of phototrophic enrichments also identified members of the novel genus Geoalkalibacter as potential ARB. Electrochemical characterization of two haloalkaliphilic, non-phototrophic Geoalkalibacter spp. showed that these bacteria were in fact capable of producing high current densities (4-8 A/m2) and using higher organic substrates under saline or alkaline conditions. The success of these selective enrichment approaches and community analyses in identifying and understanding novel ARB capabilities invites further use of MXCs as robust platforms for fundamental microbiological investigations.
ContributorsBadalamenti, Jonathan P (Author) / Krajmalnik-Brown, Rosa (Thesis advisor) / Garcia-Pichel, Ferran (Committee member) / Rittmann, Bruce E. (Committee member) / Torres, César I (Committee member) / Vermaas, Willem (Committee member) / Arizona State University (Publisher)
Created2013