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Over the past century in the southwestern United States human actions have altered hydrological processes that shape riparian ecosystems. One change, release of treated wastewater into waterways, has created perennial base flows and increased nutrient availability in ephemeral or intermittent channels. While there are benefits to utilizing treated wastewater for environmental flows, there are numerous unresolved ecohydrological issues regarding the efficacy of effluent to sustain groundwater-dependent riparian ecosystems. This research examined how nutrient-rich effluent, released into waterways with varying depths to groundwater, influences riparian plant community development. Statewide analysis of spatial and temporal patterns of effluent generation and release revealed that hydrogeomorphic setting significantly influences downstream riparian response. Approximately 70% of effluent released is into deep groundwater systems, which produced the lowest riparian development. A greenhouse study assessed how varying concentrations of nitrogen and phosphorus, emulating levels in effluent, influenced plant community response. With increasing nitrogen concentrations, vegetation emerging from riparian seed banks had greater biomass, reduced species richness, and greater abundance of nitrophilic species. The effluent-dominated Santa Cruz River in southern Arizona, with a shallow groundwater upper reach and deep groundwater lower reach, served as a study river while the San Pedro River provided a control. Analysis revealed that woody species richness and composition were similar between the two systems. Hydric pioneers (Populus fremontii, Salix gooddingii) were dominant at perennial sites on both rivers. Nitrophilic species (Conium maculatum, Polygonum lapathifolium) dominated herbaceous plant communities and plant heights were greatest in effluent-dominated reaches. Riparian vegetation declined with increasing downstream distance in the upper Santa Cruz, while patterns in the lower Santa Cruz were confounded by additional downstream agricultural input and a channelized floodplain. There were distinct longitudinal and lateral shifts toward more xeric species with increasing downstream distance and increasing lateral distance from the low-flow channel. Patterns in the upper and lower Santa Cruz reaches indicate that water availability drives riparian vegetation outcomes below treatment facilities. Ultimately, this research informs decision processes and increases adaptive capacity for water resources policy and management through the integration of ecological data in decision frameworks regarding the release of effluent for environmental flows.
ContributorsWhite, Margaret Susan (Author) / Stromberg, Juliet C. (Thesis advisor) / Fisher, Stuart G. (Committee member) / White, Dave (Committee member) / Holway, James (Committee member) / Wu, Jianguo (Committee member) / Arizona State University (Publisher)
Created2011
Description
Driven by concern over environmental, economic and social problems, small, place based communities are engaging in processes of transition to become more sustainable. These communities may be viewed as innovative front runners of a transition to a more sustainable society in general, each one, an experiment in social transformation. These experiments present learning opportunities to build robust theories of community transition and to create specific, actionable knowledge to improve, replicate, and accelerate transitions in real communities. Yet to date, there is very little empirical research into the community transition phenomenon. This thesis empirically develops an analytical framework and method for the purpose of researching community transition processes, the ultimate goal of which is to arrive at a practice of evidence based transitions. A multiple case study approach was used to investigate three community transitions while simultaneously developing the framework and method in an iterative fashion. The case studies selected were Ashton Hayes, a small English village, BedZED, an urban housing complex in London, and Forres, a small Scottish town. Each community was visited and data collected by interview and document analysis. The research design brings together elements of process tracing, transformative planning and governance, sustainability assessment, transition path analysis and transition management within a multiple case study envelope. While some preliminary insights are gained into community transitions based on the three cases the main contribution of this thesis is in the creation of the research framework and method. The general framework and method developed has potential for standardizing and synthesizing research of community transition processes leading to both theoretical and practical knowledge that allows sustainability transition to be approached with confidence and not just hope.
ContributorsForrest, Nigel (Author) / Wiek, Arnim (Thesis advisor) / Golub, Aaron (Thesis advisor) / Redman, Charles (Committee member) / White, Dave (Committee member) / Arizona State University (Publisher)
Created2011
Description
The sacred San Francisco Peaks in northern Arizona have been at the center of a series of land development controversies since the 1800s. Most recently, a controversy arose over a proposal by the ski area on the Peaks to use 100% reclaimed water to make artificial snow. The current state of the San Francisco Peaks controversy would benefit from a decision-making process that holds sustainability policy at its core. The first step towards a new sustainability-focused deliberative process regarding a complex issue like the San Francisco Peaks controversy requires understanding the issue's origins and the perspectives of the people involved in the issue. My thesis provides an historical analysis of the controversy and examines some of the laws and participatory mechanisms that have shaped the decision-making procedures and power structures from the 19th century to the early 21st century.
ContributorsMahoney, Maren (Author) / Hirt, Paul W. (Thesis advisor) / Tsosie, Rebecca (Committee member) / White, Dave (Committee member) / Arizona State University (Publisher)
Created2011
Description
Despite similar climate, ecosystem, and population size, the cities of Hermosillo, Mexico and Mesa, USA manage their water very differently. Mesa has a stable and resilient system organized around state and federal regulations. Hermosillo, after rapidly industrializing, has not been able to cope with climate change and long-term drought conditions. Water distribution statistics, stakeholders, policy structure, and government organization were combined in an organizational framework to compare the practices of the two cities. These inputs were weighed against the outcomes and the sustainability of each system. While Mesa is part of a massive metropolitan area, Hermosillo is still developing into a metropolitan center and does not have access to the same infrastructure and resources. In Hermosillo local needs are frequently discounted in favor of broad political goals.
ContributorsMoe, Rud Lamb (Author) / Chhetri, Netra (Thesis director) / White, Dave (Committee member) / Robles-Morua, Agustin (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor) / School of Sustainability (Contributor) / School of Geographical Sciences and Urban Planning (Contributor)
Created2013-05
Description
Medical practice surrounding tuberculosis (TB) treatment in two nineteenth-century Scottish charitable hospitals reveals that in developing empirically-positioned constructs of this and related diseases, medical practitioners drew upon social assumptions about women and the working classes, thus reinforcing rather than shedding cultural notions of who becomes ill and why. TB is a social disease, its distribution determined by relationships among human groups; primary among these is the patient-practitioner relationship, owing to the social role of medical treatment in restoring the ill to both health and society. To clarify the influence of cultural context upon the evolution of medical constructs of TB, I examined Glasgow Royal Infirmary (GRI) and Royal Infirmary of Edinburgh (RIE) ward journals, admissions registers, and institution management records from 1794 through 1905. Medical practice at the turn of the nineteenth century was dominated by observation and questioning of the patient, concordant with conceptions of physicians' labor as mental rather than physical. This changed with the introduction of the stethoscope in the 1820s, which together with the dissection of the poor allowed by the 1832 Anatomy Act ushered in disease concepts emphasizing pathological anatomy. Relationships between patient and practitioner also altered at this time, exhibiting distrust and medical dominance. The mid-Victorian era was notable for clinicians' increasing interest in immorality's contributions to ill health, absent in earlier practice and linked to conceptions of women and the working classes as inherently pathological. In 1882, discovery of the tubercle bacillus challenged existing nutritional, hereditary, and environmental explanations for TB. Although practitioners utilized bacteriological methods, this discovery did not revolutionize diagnosis or treatment. Rather, these older models were incorporated with perceived behavioral, environmental, and biological degradation of the working classes, rendering marginalized groups "soil" prepared for the "seeds" of disease -- at risk, but also to blame. This framework, in which marginalized groups contribute to their increased risk for disease through refusal to accord with hegemonically-established "healthy" behavior, persists. As a result, meaningful change in TB rates will need to address these longstanding contributions of social inequality to Western medical treatment.
ContributorsFarnbach Pearson, Amy Walker (Author) / Buikstra, Jane E. (Thesis advisor) / Fuchs, Rachel G (Committee member) / Brewis Slade, Alexandra (Committee member) / Roberts, Charlotte A. (Committee member) / Arizona State University (Publisher)
Created2013
Description
Food deserts are the collection of deprived food environments and limit local residents from accessing healthy and affordable food. This dissertation research in San Lorenzo, Paraguay tests if the assumptions about food deserts in the Global North are also relevant to the Global South. In the Global South, the recent growth of supermarkets is transforming local food environments and may worsen residential food access, such as through emerging more food deserts globally. This dissertation research blends the tools, theories, and frameworks from clinical nutrition, public health, and anthropology to identify the form and impact of food deserts in the market city of San Lorenzo, Paraguay. The downtown food retail district and the neighborhood food environment in San Lorenzo were mapped to assess what stores and markets are used by residents. The food stores include a variety of formal (supermarkets) and informal (local corner stores and market vendors) market sources. Food stores were characterized using an adapted version of the Nutrition Environment Measures Survey for Stores (NEMS-S) to measure store food availability, affordability, and quality. A major goal in this dissertation was to identify how and why residents select a type of food store source over another using various ethnographic interviewing techniques. Residential store selection was linked to the NEMS-S measures to establish a connection between the objective quality of the local food environment, residential behaviors in the local food environment, and nutritional health status. Using a sample of 68 households in one neighborhood, modeling suggested the quality of local food environment does effect weight (measure as body mass index), especially for those who have lived longer in poorer food environments. More generally, I find that San Lorenzo is a city-wide food desert, suggesting that research needs to establish more nuanced categories of poor food environments to address how food environments emerge health concerns in the Global South.
ContributorsGartin, Meredith (Author) / Brewis Slade, Alexandra (Thesis advisor) / Boone, Christopher (Committee member) / Wutich, Amber (Committee member) / Arizona State University (Publisher)
Created2012
Description
Background: Human papillomavirus (HPV) is the cause of 99.7% of cervical cancers. Research of cervical cancer has made this disease mostly curable in the developing world. Head and neck cancer, which is increasingly caused by HPV, still is associated with a mortality rate of 50,000 in the US annually. This study proposed to evaluate the biology of HPV-16 in head and neck tumors by using RT-qPCR to measure the RNA expression and its relation to physical status of the virus. Methods: This study was to develop an assay that uses RT-qPCR to determine the quantitative expression of HPV-16 RNA coding for proteins E1, E2, E4, E5, E6, and E7 in tumor samples. The assay development started with creation of primers. It went on to test the primers on template DNA through traditional PCR and then on DNA from HPV-16 positive cell lines, SiHa and CaSki, using RT-qPCR. This paper also describes the troubleshooting methods taken for the PCR reaction. Once the primers are verified, the RT-qPCR process can be carried out on RNA purified from tumor samples. Results: No primer sets have been confirmed to produce a product through PCR or RT-qPCR. The primer sequences match up correctly with known sequences for HPV-16 E1, E2, E4, E5, E6, and E7. RT-qPCR showed results consistent with the hypothesis. Conclusion: The RT-qPCR protocol must be optimized to confirm the primer sequences work as desired. Then primers will be used to study physical status and RNA expression in HPV-positive and HPV-negative head and neck tumor samples. This assay can help shed light on which proteins are expressed most in tumors of the head and neck and will aid in the development of future screening and treatment options.
ContributorsKhazanovich, Jakob (Author) / Anderson, Karen (Thesis director) / Mangone, Marco (Committee member) / Sundaresan, Sri Krishna (Committee member) / Barrett, The Honors College (Contributor)
Created2015-05
Description
Duchenne Muscular Dystrophy (DMD) is an X-linked recessive disease characterized by progressive muscle loss and weakness. This disease arises from a mutation that occurs on a gene that encodes for dystrophin, which results in observable muscle death and inflammation; however, the genetic changes that result from dystrophin's dysfunctionality remain unknown. Current DMD research uses mdx mice as a model, and while very useful, does not allow the study of cell-autonomous transcriptome changes during the progression of DMD due to the strong inflammatory response, perhaps hiding important therapeutic targets. C. elegans, which has a very weak inflammatory response compared to mdx mice and humans, has been used in the past to study DMD with some success. The worm ortholog of the dystrophin gene has been identified as dys-1 since its mutation phenocopies the progression of the disease and a portion of the human dystrophin gene alleviates symptoms. Importantly, the extracted RNA transcriptome from dys-1 worms showed significant change in gene expression, which needs to be further investigated with the development of a more robust model. Our lab previously published a method to isolate high-quality muscle-specific RNA from worms, which could be used to study such changes at higher resolution. We crossed the dys-1 worms with our muscle-specific strain and demonstrated that the chimeric strain exhibits similar behavioral symptoms as DMD patients as characterized by a shortened lifespan, difficulty in movement, and a decrease in speed. The presence of dys-1 and other members of the dystrophin complex in the body muscle were supported by the development of a resulting phenotype due to RNAi knockdown of each component in the body muscle; however, further experimentation is needed to reinforce this conclusion. Thus, the constructed chimeric C. elegans strain possesses unique characteristics that will allow the study of genetic changes, such as transcriptome rearrangements and dysregulation of miRNA, and how they affect the progression of DMD.
ContributorsNguyen, Thuy-Duyen Cao (Author) / Mangone, Marco (Thesis director) / Newbern, Jason (Committee member) / Duchaine, Thomas (Committee member) / School of Social Transformation (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The storm events of summer 2014 proved to be some of the highest on record for Maricopa County. Flash flooding has been an ongoing issue within Arizona during the monsoon season due to the remnants of hurricanes that result in short, high intensity storms. The proximity of these intense storm events and their corresponding flooding structures is imperative in reducing the impact of these events on the community. The analysis of the maximum precipitation events for Tempe, Scottsdale, Phoenix, Mesa, Chandler, Goodyear, Peoria, Avondale and Glendale during the summer of 2014 proved that there were many events that had a calculated recurrence of 100 years or greater. The storm event with the most precipitation events with a recurrence of 100 years or greater was September 8, 2014. This storm event also produced a streamflow response that had the highest recorded streamflow at gages near the events with a 100 year recurrence. These intervals represent a larger amount of rain during a precipitation event and this correlation suggests that short burst of extreme weather was not a trend in this data. Rather, high storm events occurred over the span of 24 hours. The most frequent response of the stream gage to this rain event was a streamflow event that has a recurrence of 2-5 years. This suggests that the channels and flooding structures used to contain the rain events were effective in reducing the amount of water and therefore effectively managing the flooding response. An analysis of newspaper commentary and an interview with a representative from the Flood Control District of Maricopa County (FCDMC) indicated that there is a disconnect between public perception and the structure of FCDMC. Through this analysis a better understanding of the FCDMC as well as the impact of severe storm events in Maricopa County was found.
ContributorsBrancati, Olivia Anne (Author) / Vivoni, Enrique (Thesis director) / White, Dave (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
microRNAs (miRNAs) are short ~22nt non-coding RNAs that regulate gene output at the post-transcriptional level. Via targeting of degenerate elements primarily in 3'untranslated regions (3'UTR) of mRNAs, miRNAs can target thousands of varying genes and suppress their protein translation. The precise mechanistic function and bio- logical role of miRNAs is not fully understood and yet it is a major contributor to a pleth- ora of diseases, including neurological disorders, muscular disorders, and cancer. Cer- tain model organisms are valuable in understanding the function of miRNA and there- fore fully understanding the biological significance of miRNA targeting. Here I report a mechanistic analysis of miRNA targeting in C. elegans, and a bioinformatic approach to aid in further investigation of miRNA targeted sequences. A few of the biologically significant mechanisms discussed in this thesis include alternative polyadenylation, RNA binding proteins, components of the miRNA recognition machinery, miRNA secondary structures, and their polymorphisms. This thesis also discusses a novel bioinformatic approach to studying miRNA biology, including computational miRNA target prediction software, and sequence complementarity. This thesis allows a better understanding of miRNA biology and presents an ideal strategy for approaching future research in miRNA targeting.
ContributorsWeigele, Dustin Keith (Author) / Mangone, Marco (Thesis director) / Katchman, Benjamin (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Life Sciences (Contributor)
Created2014-12