ABOUT THE COLLECTION

The UA Dissertations Collection provides open access to dissertations produced at the University of Arizona, including dissertations submitted online from 2005-present, and dissertations from 1924-2006 that were digitized from paper and microfilm holdings.

We have digitized the entire backfile of master's theses and doctoral dissertations that have been submitted to the University of Arizona Libraries - since 1895! If you can't find the item you want in the repository and would like to check its digitization status, please contact us.

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Please refer to the Dissertations and Theses in the UA Libraries guide for more details about UA Theses and Dissertations, and to find materials that are not available online. Email repository@u.library.arizona.edu with your questions about UA Theses and Dissertations.

Recent Submissions

  • The Application of Lower-Cost Perchlorate Remediation Methods and of Community-Engagement Efforts to Enhance Management of Superfund Sites

    Roundhill, Patrick (The University of Arizona., 2018)
    The US EPA states Community Advisory Boards (CAB’s) have proven to be effective forms of engaging communities in the geographic areas of a Superfund site. When local residents along with local scientists, engineers, community members and concerned citizens become engaged in the assessment and remediation of a US EPA Superfund site, many effects may be observed.In this study, measurements of change were taken along with observations made regarding the participants’ involvement, attitude and activities. The outcomes are defined and measured at the Apache Nitrogen Products Incorporated (ANPI). This site was studied and the community was engaged using various educational methods. The hypothesis was that if there is strong engagement of participants in various activities implemented at this contamination site, there would be a strong impact on their involvement in, and understanding of informational meetings, remediation activities, and regulatory choices. The results indicated that strong engagement and participation by the community members at contamination sites has a significant impact on their involvement, and in some cases even improving remediation efforts, and success. In parallel to the proposed community engagement activities, a novel technology was employed to treat groundwater contaminated with perchlorate and competing oxidized species such as nitrates. . The treatment of groundwater containing perchlorate by a water treatment reactor employing ZVI processes was improved with new pre-treatments by purging oxygen, removing competing oxidized materials, increasing media contact surface area, increasing residence time, and treating the iron by washing with HCl solution. This research indicates that community engagement activities may influence many aspects of Superfund site management, participants’ behaviors, decisions, and their understanding and that the regulatory decisions may be affected by CE activities coupled with a demonstration that there is an alternative remediation available.
  • The Role of CASK in Neuronal Morphogenesis and Brain Size in Drosophila: A Genetic Model of Human Intellectual Disability with Microcephaly

    Tello Vega, Judith Arane (The University of Arizona., 2018)
    CASK is a highly conserved gene with major roles in brain development and function. CASK encodes a multi-domain synaptic protein that interacts with numerous binding partners in at least three different subcellular regions. CASK is a member of the MAGUK protein family, defined by its carboxy-terminal end, which includes a guanylate kinase, PDZ and SH3 protein-interaction domains. CASK amino-terminal end, in turn, contains the CaMKinase-like domain, known as a pseudokinase. Highly expressed in neurons, CASK is localized to both pre- and post-synaptic zones, as well as to the nucleus. Mutations in human CASK cause X-linked intellectual disability (ID). There is a phenotypic spectrum of brain-development disorders caused by CASK mutations, that has been divided in two diagnostic categories. Microcephaly with pontine-cerebellar hypoplasia is the most severe, whereas FG syndrome-4 or X-linked ID with or without nystagmus cause the milder phenotype. Both of these phenotypes are accompanied by short stature. Because the CASK-mutant phenotypes in humans, I hypothesized that CASK is essential for neuronal morphogenesis. Therefore, I studied the role of Drosophila CASK in neuronal differentiation and brain development. I used the Drosophila CASK mutation, ∆18, an imprecise-excision allele that eliminates the full-length CASK protein, and the corresponding precise-excision control, Ex33. I examined neuronal morphogenesis in vitro by using primary cultures prepared from the whole CNS of wandering third instar larvae. Morphological parameters of neurite-arbor size and shape were quantified using NeuronMetricsTM software for semi-automated image analysis. CNS neurons lacking full-length CASK grew small arbors in vitro with an altered shape. This phenotype, called “bushy” combines small size (reduced length, higher-order branches, and area) with increased branch density. In addition, I found that CASK has a semi-dominant phenotype, by introducing a transgene with a WT copy of CASK the bushy phenotype was improved. To investigate whether CASK controls brain size, I studied brain morphology of Δ18 homozygous flies by histological examination of serial sections of osmium-stained, plastic-embedded pharate-adult heads. The volumes of brain and head were estimated using Olympus cellSens software. Brain and head estimated total volumes were significantly reduced in Δ18 homozygotes. Reduction in both brain and head indicates that flies have both microencephaly and microcephaly. In addition, I analyzed body size by measuring the pupal case length as a proxy for adult body size. CASK mutants have reduced body size. The small brain and reduced head found in Drosophila CASK mutants provide evidence that this is a good genetic model that parallels the CASK phenotypes in humans. In conclusion, these data suggest that the “small-brain” phenotype, associated with CASK-mutations in flies and microcephaly in children, results from decreased neuronal size and defective formation of dendritic arbors and axonal projections, rather than to a reduced number of neurons. These data strengthen the use of the Drosophila as a genetic model organism for modeling human developmental brain disorders. It would be reasonable to adapt the insights gained to develop new strategies in the field of human medicine, and its special significance regarding human CASK mutations. For instance, by performing a screen for drugs that can normalize disrupted neurons due to CASK disease-causing mutations, potential treatment strategies could be discovered.
  • Desalination in the Holy Land: Putting Ecomodernism to the Test

    Isaak, Marissa Tamar (The University of Arizona., 2018)
    In the last 15 years, Israel has built the largest seawater reverse osmosis desalination plants in the world. The plants satisfy increased demand from population and economic growth. Desalination, the removal of salts and other minerals from water in order to render it useful for drinking, irrigation, or industrial purposes, holds the promise of a reliable, high quality water source unaffected by changing climate or shifting geopolitics. Desalination appears to solve one of the world's most intractable problems: freshwater scarcity. This dissertation will use Israel as a test case to examine underlying theoretical and empirical challenges associated with implementing desalination, asking the question, “Does desalination accomplish all that it promises?” The introductory chapter situates the Israeli case in the larger global trends toward water augmentation through desalination. Chapter two contextualizes the research in the existing literature of ecomodernism, wherein technology is marshaled to solve environmental issues, new “post-political” institutions manage resources, and consensus can facilitate win-win solutions. The chapter also addresses the contribution of science and technology studies, political ecology, and political geography, each of which raises important questions to be addressed by the dissertation. This dissertation then applies ecomodernism to the case of desalination in Israel, asking the following questions: 1. How did Israel become ecomodern? What changes in the water sector over the course of the country’s history brought it to its current status? 2. With the implementation of ecomodern ideals, has Israel accomplished its environmental goals in the water sector? 3. How did political and institutional shifts enable ecomodern desalination to flourish in Israel? To answer these questions, chapter three traces a synthetic history of Israeli water, examining how a sector driven by socialist and Zionist ideology, transitioned into an ecomodern one based on the principles of economic efficiency and rational decisionmaking. Chapter four considers how Israeli environmental non-governmental organizations came to support desalination on environmental grounds despite evidence questioning the efficacy of the “substitution effect,” or the ability for desalinated water to substitute for natural sources. Chapter five points to advent of a new institution, the Israeli Water Authority, and its approach to ensuring post-political consensus in the sector. The dissertation concludes with lessons that other nations might consider when considering a desalination strategy, including environmental and transparency safeguards.
  • Adaptation to Global Change in Farmer-Managed Irrigation Systems of the Gandaki Basin in Nepal

    Thapa, Bhuwan (The University of Arizona., 2018)
    The food security and livelihood of millions of marginal farmers depend on the productivity of smallholder farms that account for 50 percent of global farmland production. However, these farms are increasingly under stress from global change, including climate change, market integration, and international out-migration. In addition, there is limited information on how farmers and local irrigation institutions cope with and adapt to these multilevel changes. Using the case of 379 farmers located in 12 farmer-managed irrigation systems (FMIS) in the Gandaki Basin of Central and Western Nepal, this study explores how FMIS and farmers cope with and adapt to water stress. Drawing on empirical evidence of these FMIS, I build on the understanding of adaptive capacity -- a central aspect of institutional adaptation -- based on five capitals (human, social, physical, natural and financial) and two governance attributes. The institutional adaptation of FMIS can be broadly categorized into structural (e.g. canal lining, temporary dams) and operational measures (e.g. water allocation rules). Some of the factors that facilitate effective adaptation include collective action, leadership, and good governance as well as physical attributes including the presence of an economically feasible alternative water source. At the farmers’ level, I studied crop choice, which emerged as one of the common adaptation strategies to global change, by incorporating multilevel drivers at household, institution, and regional level. The household attributes included farmer’s demographic and socioeconomic characteristics, institutional information focused on irrigation system attributes, and regional variables included precipitation and temperature variables. The study showed that crop choice is driven by biophysical system, (measured by the size of the river that feeds the irrigation system), market integration, and farmer’s age. Climate change and variability act as a threat multiplier because they compound the existing impacts the system faces from social, economic and biophysical changes. Overall, the dissertation helps us better understand the institutional adaptive capacity that incorporates both the assets and governance-based dimensions, expands the typology of irrigated agriculture to include both the structural and operational measures. Further, the multilevel modeling adds as a quantitative tool to assess the effects of global change. The dissertation, therefore, makes theoretical, empirical, and methodological contributions to the literature on adaptation and resilience.
  • Perpendicular Magnetic Tunnel Junctions with Unconventional Tunneling Barriers

    Newhouse-Illige, Ty Alexander (The University of Arizona., 2018)
    Spintronics has become an area of interest for future computing beyond the transistor. Of particular interest is the storage of data in magnetic states with the use of Magnetic Tunneling Junctions (MTJs). An MTJ consists of two ferromagnetic layers seperated by a thin insulating barrier, the standard stucture being CoFeB/MgO/CoFeB. One focus of current spintronics research is lowering the switching energy of nanomagnets in MTJs. A nanomagnet can be switched by a magnetic field governed by Ampere’s law, or by current-induced spin transfer torques and spin-orbit torques. For future spintronic applications, it is highly desirable to accomplish magnetization switching with voltage, which, by eliminating Joule heating, could dramatically reduce the switching energy. In this work two new MTJ barrier materials are investigates with a focus on the unique voltage controllable magnetic properties they bring to MTJs with perpendicular magnetic anisotropy (pMTJs). For the first-time voltage controllable interlayer coupling (VCIC) has been experimentally demonstrated with the use of a GdOX tunneling barrier. Due to the interfacial nature of the magnetism, the ability to move oxygen vacancies within the barrier, and a large proximity-induced magnetization of GdOx, both the magnitude and the sign of the interlayer coupling in these junctions can be directly controlled by voltage. In the final portion of this dissertation pMTJs with an antiferromagnetic CrOx tunneling barrier are explored. Due to the unique properties of CrOX the direction of the exchange bias between it and the bottom CoFeB FM layer can be changed thus modifying the hysteretic properties of the MTJ.
  • Analytical Investigation of The Behavior of Seismic Collectors in Steel Building Structures

    Agarwal, Anshul (The University of Arizona., 2018)
    This dissertation describes an analytical examination on the fundamental behavior of seismic collectors in steel building structures. Seismic collectors are key elements that collect the inertial forces that are generated in the floor mass in an earthquake and transfers them to the vertical elements of the seismic force resisting system (e.g. braced frames, shear walls, etc.). Collectors, while playing a vital role in seismic load path, have not been given proper attention in research. The fundamental behavior of seismic collectors is not clearly understood. Seismic collectors in a steel building are part of a composite floor with steel deck and concrete slab connected typically using shear studs. In an earthquake, the primary collector forces acting on a collector are axial forces. A key design of collectors includes: (1) designing the collector connections for tension; and, (2) collector members for compression, which involves stability of the collector member. In addition to the axial collector forces, the seismic collector also carries shear due to gravity load and forces due to frame drift. The fundamental behavior of collector connections under combination of load (tension, gravity and frame action) and collector members under compression is addressed in this dissertation. The analytical research covered in this dissertation includes three major parts: (1) The collector load path in a composite floor system is evaluated (horizontal plane) using 3D models of a floor. The examination includes elastic behavior to ultimate. The analytical results are compared with the current design practices. The models are based on an evaluation structure designed for the project. (2) The fundamental behavior of collector connection is examined primarily under axial load using 2D plane stress models. Collector connections are also evaluated for loads due to frame action in combination with axial load. Load path in the vertical plane of the collector is evaluated. Parametric study of key design parameters on the behavior of collector connection is also evaluated. Analytical work performed for large scale testing for collector connections is included. (3) The stability limit states of collector members is examined with 3D models of the collector and the gravity system. The analytical work to support large scale testing of collector members is also included. This dissertation describes the concept and scope of analytical research, analytical results, conclusions, and suggests future work. The conclusions include analytical results for the behavior of collector connections, collector load path in a composite steel deck diaphragm and stability modes of collector. The effect of various parameters on the behavior of collector connection is included in the results. Design recommendations are provided for collector connections.
  • The Role of Nebulin and Its C-terminus in Sarcomeric Structure, Function, and Disease

    Li, Frank W. (The University of Arizona., 2018)
    Nebulin is a large skeletal muscle protein wound around the thin filaments, with its C-terminus embedded within the Z-disk and its N-terminus extending out towards the thin filament pointed end. Studies into nebulin’s function have been limited by the conventional knockout model’s fragility and nebulin’s role in adult muscle remains poorly understood. Therefore, a nebulin knockout model that survives into adulthood is needed. Additionally, a domain-specific study of nebulin’s C-terminus would allow for a better understanding of changes at the Z-disk and how that could contribute to nemaline myopathy. This dissertation examines two novel models in order to address these points. Characterization of a conditional nebulin knockout model (Neb cKO), which delayed nebulin deletion using a MCK-Cre transgene, found severe myopathy and a persistent force deficit. Changes in MHC isoform elucidated the biological causes of these deficits. The nebulin truncation model removed the final two unique C-terminal domains, the serine-rich region and the SH3 domain (NebΔ163-165). Homozygous NebΔ163-165 mice that survive past the neonatal stage exhibit a mild weight deficit. Characterization of these mice revealed that the truncation caused a moderate myopathy phenotype reminiscent of nemaline myopathy despite the majority of nebulin being localized properly in the thin filaments. This phenotype included muscle weight loss, changes in sarcomere structure, as well as a decrease in force production. GST pulldown experiments found novel binding partners with the serine-rich region, several of which are associated with myopathies. The comparison of these two models emphasizes the role of nebulin’s C-terminus in the muscle sarcomere, finding that this small region is necessary for proper sarcomeric development and shows that its loss is sufficient to induce myopathy.
  • The Children of the Cosmic Race: The Planning and Celebration of the 1968 Cultural Olympics in Mexico City

    Huntley, Allison (The University of Arizona., 2018)
    In his seminal 1925 essay, Mexican educator José Vasconcelos argued that his nation was a product of the biological and cultural union of the indigenous and the European after whom he named his work: the cosmic race (la raza cósmica).  This idea became the backbone of national identity in the years to come, and it influenced art, education, and architecture in the country.  A generation later, those who were born, received their educations, and began their professional lives in that cultural milieu planned the 1968 Summer Olympics in Mexico City where they sought to put this vision of their identity and nation on display.  As a part of this effort, the Organizing Committee of the XIX Olympiad held a yearlong festival called the Cultural Olympics that brought dancers, musicians, architects, artwork, and scientific exhibits to Mexico from around the world. The goal of the cultural program was to allow participants the opportunity to present their national histories, art, and research to a global audience in an atmosphere of cooperation and friendship.   With these events, the planners sought to establish their contributions to the Olympic Movement as well as to the international community.  Thus, understanding them offers a way to consider the lasting impact of Vasconcelos’s work and contextualize the legacies of the 1968 Games that occurred in a year fraught with political and social upheaval.  My research focuses on archival and published sources such as the brochures, pamphlets, and reports produced by the Department of Artistic and Cultural Activities. I also utilized periodicals, published research, and an interview that capture the reactions of coordinators, participants and spectators.
  • Empire, Province, and Power: Chorbadzhi (Çorbacı) Networks in the Ottoman Empire, 1790s-1860s

    Uluisik, Secil (The University of Arizona., 2018)
    Provincial political culture in the Ottoman Empire went through multiple transformations and crises during the later eighteenth century leading to power reconfigurations in localities across the Empire. Although Muslim local notables (ayans) of this period have enjoyed a sustained scholarly interest, Christian provincial power holders such as the Chorbadzhis (Çorbacıs) have remained neglected despite their remarkable yet un-institutionalized roles in the Ottoman world. This dissertation examines the emergence of chorbadzhis and their rise to power through the rich web of networks they established. It explores their political, commercial, social and clerical networks, tax collection practices, identity shifts, and power negotiations with the Ottoman state that transgressed the assumed boundaries of the Millet system. Providing microhistories of individual Christian provincial actors like chorbadzhis, this dissertation offers an example of history writing that connects micro- to macro-scales. Using chorbadzhis of the Balkans in 1790s–1860s as a lens, this dissertation decenters the Ottoman Empire by shifting the focus from Istanbul to localities; from institutions to peoples; from Muslims to Christians and Jews; from communities to individuals; from official narratives to practicalities. Chapter I sets the theoretical background of the project, critically assessing the existing historiographies, paradigms, terminologies, and periodizations that neglected chorbadzhis. Providing a spatial distribution of chorbadzhis across the Empire, this dissertation demonstrates that Chorbadzhis were not confined to their local regions, but they were indeed an empire-wide phenomenon. Chapter II looks at how chorbadzhis ascended during the 1790s and consolidated their power around 1850s. Focusing on their roles in the provisioning system, this chapter argues that chronic banditry, disease epidemics, and long-lasting wars, and inter-imperial rivalry played a role in chorbadzhis’ emergence and expansion as the Ottoman Empire’s alternative local partners. Complementing the holistic analyses of the earlier chapters, Chapters III and IV bring specific chorbadzhi families into focus, exploring their local, intra- and inter-imperial, and even global commercial networks. By analyzing their encounters with various social and political actors including merchants, bandits, local priests, and state officials, these chapters reveal how these chorbadzhi families maintained their influence up until the 1860s. To achieve a multi-dimensional account, this dissertation utilizes sources from archives in Turkey, Bulgaria, Serbia, and Austria as well as published materials in a number of languages including Ottoman/Modern Turkish and Bulgarian along with major European and Slavic languages.
  • Starless Clumps and the Earliest Phases of High-mass Star Formation in the Milky Way

    Svoboda, Brian (The University of Arizona., 2018)
    High-mass stars are key to regulating the interstellar medium, star formation activity, and overall evolution of galaxies, but their formation remains an open problem in astrophysics. In order to understand the physical conditions during the earliest phases of high-mass star formation, I present observational studies of dense starless clump candidates (SCCs) that show no signatures of star formation activity. I identify 2223 SCCs from the 1.1 mm Bolocam Galactic Plane Survey, systematically analyze their physical properties, and show that the starless phase is not represented by a single timescale, but evolves more rapidly with increasing clump mass. To investigate the sub-structure in SCCs at high spatial resolution, I present an analysis of the 12 most high-mass SCCs within 5 kpc using Atacama Large Millimeter/sub-millimeter Array. I report previously undetected low-luminosity protostars in 11 out of 12 SCCs, fragmentation equal to the thermal Jeans length of the clump, and the discovery of two high-mass starless core candidates. While uncertainties remain concerning the star formation efficiency in this sample, these observational facts are consistent with models where high-mass stars form from initially low- to intermediate-mass protostars that accrete most of their mass from the surrounding clump.
  • Analytical Investigation of Floating Panel System for Seismic Resistant Precast Building Structures

    Shakya, Ulina (The University of Arizona., 2018)
    Precast concrete structures are gaining popularity due to its lesser construction time and easy constructability in the modern era. These structures are usually long span with the shear walls at the edges for a lateral support. Even though the diaphragm design forces have increased, researchers and practitioners agreed that more research on the seismic behavior of the precast concrete structures is needed. This dissertation proposal proposes an innovative connection technique in the precast concrete structures. The primary objective of the dissertation proposal is to show the performance effectiveness of the proposed system during a seismic event. To accomplish this, two- dimensional (2D), and three-dimensional (3D) numerical models of the diaphragm with shear walls have been developed using a Finite Element (FE) analysis program, ANSYS. A suite of ten spectrums-compatible earthquakes with different frequency contents are subjected to the FE models. The effective response of the proposed system is being studied.
  • Receptive Bilingual Motivational Selves: A Cross-Sectional Analysis of Heritage Language Learners’ Imagining and Creating Success

    McEvoy, Trudie Clark (The University of Arizona., 2018)
    Since it is frequently the case that receptive bilinguals of Spanish are unable to communicate comfortably with their monolingual Spanish speaking loved ones and live in a country where Spanish is a highly marketable skill, students have pressing reasons to be both personally and professionally motivated to master their Heritage language (HL). Receptive bilinguals, as a part of the Heritage Language Learner (HLL) population are unfortunately excluded from both definitions of L2 and HLLs, and understandably frequently discontinue their studies before achieving a minor in their Heritage Language (Beaudrie, 2009; Beaudrie & Ducar, 2005). While research regarding HLL experience acquiring Spanish in the United States has exploded since the 1990s (Valdés, 2001; Carreira, 2004; Lynch, 2014); more recently, and to a lesser extent, there is a growing body of research regarding HLL motivation (Ducar, 2012; Yanguas, 2010; Oh & Nash, 2014; Husseinalli, 2006; Lee, 2006). There is, unfortunately, a dearth of research regarding the language learner motivation of receptive bilinguals (Beaudrie & Ducar, 2005; Vergara Wilson, 2011; Xie, 2014). The current study seeks to fill this gap in the literature and understand the receptive bilingual experience not just as beginner learners but also as they progress throughout their university studies in a Heritage Language program. Using the L2 Motivational Self System, and more specifically the motivational selves as described by Dörnyei (2009), this study contributes a deeper understanding of how the construction of possible selves serves to create motivation in this particular population at varying points along their learning trajectories. It first describes themes present in the motivational selves of this understudied population as well as societal ideologies that are road blocks that students encounter on their way to successfully creating motivation. These common themes are then analyzed across 5 groups of participants according to the number of courses they have completed in the program, from those who have dropped the program after completing a single semester to those who have completed a minor in Spanish. It identifies several factors which trend in particular directions across participant groups, several of which reinforce the previously identified roadblocks. Finally, this study identifies strategies for coping with these road blocks. It contributes to our understanding of motivation as process, the overlap in motivational orientations, and themes within learning trajectories of receptive bilinguals. As one participant described, “I was never legitimately taught Spanish. It’s almost as though I had been sitting in a math class for years but never actually doing anything [and] one day just being able to take the test from what I had picked up in passing.” This participant’s experience, and other receptive bilingual experiences, are outside of the conventional understandings of HL or L2 labels. Therefore, this research serves to describe the hopes and dreams of this understudied population through an analysis of their motivational selves.
  • Examining Intersectional Inequality and Civic Development in Adolescence and Young Adulthood

    Shramko, Maura Elizabeth (The University of Arizona., 2018)
    Youth civic engagement is beneficial to young people, their communities, and U.S. democracy. Yet, societal marginalization (i.e., discrimination, differential access to civic resources) may influence youth civic engagement. Guided by intersectionality and sociopolitical development frameworks, the three studies in this dissertation investigated how intersectional inequality relates to youth civic engagement. The first study estimated latent profiles of discrimination and attributions among adolescents. Associations between profile membership and later civic engagement (critical social analysis, civic agency, sociopolitical action) were examined. Findings indicate intersectional discrimination predicted higher levels of civic engagement. The second study identified latent profiles of civic resources across contexts (family, school, extracurricular) among Latina/o adolescents, and investigated whether access to resources varied by intersections with ethnicity: age, gender, immigrant generational status, and socioeconomic status. Latent transition analysis assessed the stability of profile membership over time by each intersection. Latina/o youths’ access to contextual civic opportunities and resources varied from low to medium to high resources. Latina/o youth more frequently maintained or gained access, rather than lost access, to civic resources. The third study examined whether young adults’ experience of intersectional discrimination affected their civic engagement during and after the 2016 presidential election. As in study 1, latent profiles of discrimination were identified. Growth models of civic engagement (critical social analysis, sociopolitical action) were estimated, and interactions between intersectional discrimination and time, and between civic agency, discrimination, and time were tested. Discrimination was not associated with civic engagement. Overall, findings provide evidence that marginalized young people may show resilience in their access to civic resources and opportunities, and via civic engagement as they work to address injustice in their contexts of development.
  • Planning and Operational Analyses for A New Intercity Transit Service

    Ranjbari, Andisheh (The University of Arizona., 2018)
    Intercity travel has been on the rise in the last few decades, resulting in severe congestion on intercity freeway corridors. Existing modes such as air, rail, and bus services have respective limitations and have not been effective in alleviating the present and future intercity travel challenges. Our proposed solution is ‘Flexpress’, a flexible and express intercity transit service that is conceived and designed to accomplish three major operating characteristics: high speed, high capacity and high accessibility. Flexpress will offer service in tire-based low-profile transit vehicles, capable of cruising at up to 150 mph on a dedicated lane on freeways, and will have multiple terminals in urban areas to provide passengers with higher levels of accessibility to their origin and destination. In the urban area, the vehicles will be driven by a driver at regular traffic speeds while picking up/dropping off passengers at terminals, but once entering the dedicated lane, the driver initiates the auto-pilot mode and the vehicle will travel with maximum speed, until reaching the metro area, where the driver regains control. This dissertation is focused on planning and operational analyses for the proposed Flexpress service. As a case study, Flexpress is considered as an intercity transit service between the metropolitan areas of Tucson and Phoenix, in Arizona, USA. A demand analysis study is conducted to model the mode choice behavior of individuals when making intercity travel and to identify the significant factors influencing their mode choices. The feasibility and potential market of Flexpress is studied in competition with other intercity travel modes such as drive, rail, regular bus, and demand-responsive shuttle service. To collect the behavioral data, an interactive Stated Preference survey is employed that estimates the respondent-specific attribute values in a real-time manner, customized to the individual information provided by the respondents. Such a process helps present a choice set that reflects each individual’s travel context more realistically. The collected data showed that a transportation option with the characteristics of Flexpress has the potential to take up a considerable market share, even larger than driving. Having estimated a discrete choice model, the significant factors influencing the choice preference were recognized, and the analysis provided insightful findings toward intercity mode choice behavior and improving intercity transit services. As a side study, an analysis is conducted to investigate the effects of alternatives’ labels on people’s choice making behaviors and also to understand how and why the respondents change their choices once they learn about alternatives’ labels. To design the Flexpress network, a network design problem formulation and solution procedure is presented for intercity transit services that have multiple routes and serve multiple terminals in the origin and destination cities. The proposed solution procedure consists of three steps: 1) a set of candidate terminals are selected; 2) candidate routes are generated between those terminals using a k-shortest path algorithm; 3) a mixed-integer linear optimization model finds the optimal routes, terminals, frequencies, fleet size and depot locations, given a set of constraints and the objective of minimizing total passenger travel time and vehicle deadheading time. The solution procedure was implemented for Flexpress service in the study corridor. The final routes found by the model looked reasonable, and the sensitivity analysis showed that the objective function is most sensitive to changes in the minimum demand satisfaction ratio and then to the maximum number of routes and the maximum fleet size. A solution framework is also proposed for operational analysis and financial assessment of transit services that considers the passenger behavior and the elasticity of transit demand to service characteristics. The proposed solution framework integrates a dynamic transit passenger assignment model with the intercity mode choice model and an adopted service design module, and iterates these methods until an equilibrium between fares and frequencies is reached. The transit assignment model, called Fast-Trips, is a schedule-based and capacity-constrained model that considers hyperpaths in transit route choice and captures passenger behavior at a high resolution. The solution framework was implemented for Flexpress service in the study corridor, and the system performance is studied for multiple fare policy and frequency design scenarios. The results showed that the scenarios with designed-oriented frequencies had lower ratios of revenue to operating cost (R/C ratio), compared to those where frequencies were set based on the passenger path choice behaviors and route usage. The R/C ratio increases with an increase in fares and a decrease in frequencies, but the sensitivity analysis indicated that there are multiple ways to achieve a certain R/C ratio. So, it would be the other objectives and the operator’s priorities that define the final design and service characteristics. Moreover, it was shown that if frequencies are designed efficiently, not only will the system be profitable, but also with an increase in fares, it may be possible to achieve high R/C ratios to account for the capital costs as well.
  • Experimental and Computational Analysis of Bioethanol Production from Sweet Sorghum

    Ebrahimiaqda, Elham (The University of Arizona., 2018)
    Environmental, economic and energy security aspects of relying on fossil fuels motivate research on alternative fuel sources such as biofuel. Sweet sorghum, with high productivity and low production cost, has enormous potential as a bioenergy crop. The use of energy, water, land, equipment, labor and other resources are factors affecting final cost of bioethanol production from sweet sorghum. Fermentation, distillation and dewatering are main chemical processes involved in production of 99.8 wt% dehydrated ethanol from sweet sorghum juice. Distillation and dehydration are final stages of the production and demand high amount of cost and energy. One of the goals of this research is optimization and comparison of two main commonly used dehydration technologies of extractive distillation and pressure swing adsorption (PSA) alongside with distillation step. ASPEN PLUS software version 11.1 and MATLAB programming language were used to find the optimized cost and energy usage for both dehydration methods. Our results show applying extractive distillation using ethylene glycol as entrainer leads to a total annualized cost that is 12% less than that of PSA with molecular sieve. The other goal of this project is evaluation and optimization of the fermentation process that yields bioethanol from sweet sorghum juice. The effect of three main factors of temperature, pH and dissolved oxygen (DO) on ethanol yield efficacy was studied. Fermentation experiments were done on sweet sorghum juice from M81E cultivar, grown in the University of Arizona West Campus Agricultural Center in Tucson, Arizona. A full factorial design with center points were applied to study the influence of the main factors and their binary and ternary interactions on ethanol yield produced from sweet sorghum juice fermented by Saccharomyces cerevisiae (Ethanol Red). Maximum ethanol yield efficiency of 0.74 was obtained at pH (5.5), temperature 6 (28 °C) and a zero dissolved oxygen conditions. This value has good agreement with maximum experimental yield efficiency of 0.75 for bioethanol produced from the M81E variety.
  • Organizational Form Emergence and the Rise of Vendor Management Organizations

    O'Brien, Laureen K. (The University of Arizona., 2018)
    This dissertation examines the emergence and consequences of a new organizational form, the Vendor Management Organization (VMO), a type of employment broker specializing in large-scale sourcing of contingent workers. The project follows the phenomenon from its beginnings as a disparate practice to its emergence into a well-established form. The project addresses two main research questions: 1) how did VMOs emerge as a form, spread, and become a powerful player in contingent staffing?; and 2) how did the emergence of VMOs restructure and transform interorganizational relationships between three groups of actors: client companies, VMOs, and temporary help agencies? Chapter 1 introduces vendor management and VMOs and provides an overview of the research. Chapter 2 presents the available body of literature on form emergence and the entrepreneurial, technological, and population-based directions of that strain of research. It then introduces resource dependence, transaction cost economics, and corporate control views of the firm as theories that could aid our understanding of organizational form emergence. Chapter 3 describes the study’s research methodology and details data collection strategies, sampling procedures, and research implementation. Chapter 4 provides an analysis of the archival data and describes the emergence of the VMO form. Chapter 5 lays out the consequences of VMOs emergence for interorganizational relationships between related entities. Chapter 6 concludes the dissertation with an overview of study results and findings, research insights, theoretical implications, limitations, and directions for future research. The dissertation is built upon two streams of data: an archival analysis of media accounts of vendor management and VMOs over a 20-year period; and semi-structured interviews with 45 executives and managers of temporary help agencies, VMOs, and client companies. The archival data covers 1995-2015, a period within which VMOs emerged as an identifiable, though fledgling, organizational form and later expanded to become a global force in contingent staffing. Interviews with representatives from the three groups offered detailed information on VMOs and vendor management. The observations and attitudes that emerged during the interviews contributed context and nuance to the archival data. I investigated and analyzed the VMO phenomenon incorporating grounded theory methodology and organizational theories of external environment. By combining the two approaches, I created a view of organizational emergence that stresses the relational, structural, and pragmatic aspects of form emergence. I found that interactive engagements between organizations contributed to the emergence and rise of VMOs, and suggest that relational activities between organizations, such as information asymmetry, transaction cost concerns, power dynamics, and prevailing corporate values, are powerful and often overlooked components of organizational form emergence. VMOs, which evolved over three phases – inception, mobilization, and institutionalization – reflected larger economic, corporate, and technological changes that 1) changed power dynamics between the organizational actors, 2) facilitated the creation and rise of the VMO form, and 3) helped construct the strategies VMOs used to promote and legitimate their roles as intermediaries. The rise of VMOs also had profound implications for interorganizational relationships in contingent staffing. The presence of a VMO eliminated direct relationships, and created mediated relationships, between the client companies and temporary help agencies, and established new direct relationships between VMOs and client companies. This dissertation contributes to the theoretical perspectives that inform the emergence of new organizational forms by focusing on the role of relational activities and theories of organizational environment. VMOs are a new phenomenon, and the study of their emergence is a unique case within which to trace an organizational field’s inception, growth, and movement from a practice into a legitimate industry. I suggest that an important but understudied way in which new organizational forms are created occurs when economic conditions, changes in corporate values, and the involvement of different organizational actors provide the opportunity for a new form to emerge.
  • New Approaches to Advance Ion Channel Sensor Development

    Wang, Xuemin (The University of Arizona., 2018)
    Cellular secretion regulates cell communication and function. The ability to detect and quantify the release of hormones and neurotransmitters provides deeper understanding of cell signaling pathways. Ion channel sensors demonstrate a high potential for detecting cellular secretion with high sensitivity and selectivity, as well as adequate spatial and temporal resolution for real-time subcellular detection. Ion channel sensors utilize ligand-gated ion channels (LGICs) as recognition elements, enabling detection of ligand-receptor binding with high specificity. LGICs serve as signal transducers that transduce ligand binding events into highly sensitive current measurements, allowing label-free detection of hormone and neurotransmitters that are neither optically, nor electrochemically active. The work within this dissertation describes three new approaches to further advance ion channel sensor development. First, in vitro expression of eGFP-Kir6.2 was explored and verified using fluorescence microscopy, SDS-PAGE and dot blot. Electrophysiological measurement confirmed the successful expression of functional ion channels with expected pore conductance and antagonist sensitivity. The new expression method allowed fast and purification-free protein production, greatly reducing the time and technical barrier for ion channel sensor fabrication. Second, a dual-barrel ion channel probe was described to provide precise positioning of sniffer sensor using access resistance as feedback signal. Selective formation of polymer scaffold stabilized black lipid membrane across one barrel was confirmed and enabled membrane protein insertions. Precise positioning of the sensor will increase sensor reproducibility, thus providing accurate measurements of cellular release. Finally, a surface modified microfluidic valve was fabricated with > 70 fold enhancement in electrical resistance, enabling the isolation of ion channel signals in pA regime. The microfluidic valve provides a simple but cost-effective alternative for high throughput parallel electrophysiology. The efforts to advance the development of ion channel sensors will greatly improve our understanding of the biological system, benefiting disease diagnosis and treatment.
  • The Research Problem of Research Obstacles

    McBee, David Jeremy (The University of Arizona., 2018)
    Problem solving is regarded as an essential to scientific work, yet remains a curiously understudied topic. This is due, in part, to the different meanings attributed to the word ‘problem’ by different lines of research and different disciplines. While scientists do choose research topics, battle for control of their jurisdictions, and have opportunities to apply their abstract knowledge, they also face research obstacles – problems that must be overcome in order to fulfill the aims of research. A lot can – and does – go wrong during the course of innovative scientific work. In fact, many of the most innovative scientific fields have high failure rates. This is very apparent in the biopharmaceutical field, the field that I chose to study. Biopharmaceutical scientists must often deal with research-related obstacles that crop up during the course of their work if their projects are to move forward. Fortunately, these biopharmaceutical scientists do not face such obstacles alone but have the support and backing of their organizations, project teams, and social networks. Thus, problem solving in the realm of biopharmaceutical science involves social processes. My dissertation seeks to provide an understanding of these social processes through three studies. The first study investigates how biopharmaceutical scientists deal with research obstacles by interviewing 36 core scientists working on biopharmaceutical research and development. These conversations reveal that personal jurisdictions, functional area teams, and multifunctional project teams provide a template of action for biopharmaceutical scientists that draws upon specialist knowledge and interdisciplinary teamwork. Additionally, scientists’ accounts of legal boundaries associated with utilizing interorganizational network ties suggests the biopharmaceutical field relies on formal authority structures to organize scientists’ problem solving efforts. The second study asks what kind of social network contacts facilitate problem solving. Recent work on social networks and creative innovation claims that social network contacts with different types of characteristics will prove useful for different innovation phases. Because problem solving moves through similar phases, I argue by analogy that different types of social network contacts will prove useful for different problem solving phases. Further, I test whether path dependence exists between problem solving phases. To address these questions, I utilize a multi-level path model to model survey data from members of the American Association of Pharmaceutical Scientists. Results indicate that biopharmaceutical scientists associate the characteristics of strong social network ties, leadership relationships, and competence-based trust with problem solving. Additionally, social network contacts that provide useful assistance at an earlier problem solving phase are more likely to provide useful assistance at a later problem solving phase. Thus, path dependence exists between phases of problem solving. The third study asks why some biopharmaceutical scientists are more effective at problem solving than others. To ask this question, I draw upon research on the strength of ties, the knowledge components of networks, individual job performance, team science, and problem solving. To address this question, I utilize the same survey of biopharmaceutical scientists affiliated with the American Association of Pharmaceutical Scientists. Results of a structural equation model show two pathways. The first emphasizes social networks. The influence of the strength of ties on scientists’ problem solving effectiveness is mediated by the knowledge components of networks. The second path emphasizes performance. The influence of team performance runs through the job performance of individual scientists. These studies build a holistic understanding of the social processes associated with problem solving in the field of biopharmaceutical science.
  • Multilevel Optimization for Resilient Planning and Operations of Interdependent Infrastructures

    Hou, Shanshan (The University of Arizona., 2018)
    In general, infrastructure is defined as "the physical components of interrelated systems providing commodities and services essential to enable, sustain, or enhance societal living conditions" (Fulmer, 2009). With the development of scientific technology and social economy, many infrastructures become highly interconnected and interdependent. The interdependence is the mutual reliance between two or more groups. To satisfy future human needs for a better quality of life and sustainable society development, the planning and operations or management of infrastructures should not only meet the resilience standards, but also consider the complexity factors such as interdependencies among infrastructures to achieve societal and economic goals. Interdependencies are significant at specific of hazard intensities and tend to quickly propagate the effects. An event in one system will lead vulnerabilities of the other systems, which means the failure of partial elements in one system may trigger failures of dependent elements in other systems, and this may happen recursively as cascading failures. Vulnerability analysis is helpful to detect the critical parts of infrastructures which should be protected, especially under potential cascading failures. In this study, we apply multilevel optimization approaches to model the interdependent infrastructure planning and operations or management. Multilevel optimization focuses on the hierarchy structure, in which the decisions are taken in different levels. The constraint domain associated with a multilevel optimization problem is implicitly determined by a series of optimization problems which must be solved in predetermined sequences. Generally, multilevel optimization is suitable for the problems in which each decision maker just controls part of decision variables, and there is a hierarchy of all decision makers. First, we study interdependent energy and water networks. Energy network provides power for water extraction, collection, pumping operation and water or wastewater treatment. Water network supplies water to energy generation, cooling system and equipment cleaning. These two networks comprise an interdependent network, and rely on each other. The nexus between energy and water has emerged as a significant issue concerning the economics, reliability, and resilience of both systems. Most of current approaches deal with the planning and operations or management of an isolated network as an integration, but few research on system expansion has considered the interdependence between energy and water systems, resulting in plans that might have poor performance due to water or energy availability in the future. It is the time to consider water and energy as interdependent network to make multilevel decisions in the planning and operations or management periods. We propose a long-term energy and water system expansion planning framework that not only models the operations of both systems but also captures the interdependence between the operations of energy and water systems. This is a coordinated and unified intelligent system-wide optimization approach to incorporate intra- and inter-infrastructure decisions. Second, we propose a mixed integer programming model to study the operations of power grid with renewable energy integration and water limitations. The development of the renewable energy helps decrease the energy resources shortage pressure and greenhouse gas emissions. However, the intermittency issues of renewable energy put a burden for integration. We propose the robust optimization modeling approach to deal with the uncertainty issue of the renewable energy. Considering the electricity generation, water is the most important resource. It is necessary for thermal power plants, hydropower plants, and also the renewable energy power plants. The amount of water used in the cooling system is large. But the water supply amount may be strictly limited in some areas due to the different water availability. The electricity power generation could be affected by the total water supply amount in the system. On the other hand, the water usage to generate per unit of electricity power in different types of energy sources could be changed in the future as technology develops. These are two aspects we need to consider about the water sensitivity analysis. Last, we choose the power grid and its control communication network as a case to analyze the vulnerability of interdependent infrastructures. The power grid provides power for the communication network's operation, and the communication network controls the power grid's performance. Due to the complex connections between them, the vulnerability of each network increases dramatically. The removal of critical nodes or edges in power grid will not only affect the nodes and edges in this network, but also influence the nodes and edges in the communication network. The presence of interdependencies could dramatically augment the vulnerability of infrastructures through cascading failures. The failures may initially happen in the power grid, then go through into the communication network, and go back to the power grid, repeating this process till the final steady state. This cascading failure could trigger the most severe loss in the interdependent networks. We propose integer programming models to identify the most vulnerable network elements (nodes and edges) whose removal will result in minimal survivable mutually connected components after the cascading failure process. Taking some measurements to protect the most vulnerable elements could help redesign and rebuild the networks more resilient.
  • Būr Saʿīd/Port Said, 1859-1900: Migration, Urbanization, and Empire in an Egyptian and Mediterranean Port-City

    Carminati, Lucia (The University of Arizona., 2018)
    Between the 1850s and the early 1900s, an increasing number of migrants landed on Egypt’s shores. Egypt provided an alternative to stagnant economies, offered political stability, and even granted a system of separate judicial courts for foreigners. Within Egypt itself, more and more people moved from villages to cities, such as the rapidly growing Cairo and Alexandria and the brand-new towns of Port Said and Ismailia, arising from scratch along the works for the Suez Canal. My work builds on the existing historiography on migration and urbanization in the Middle East. Scholars have accounted for migrant communities in their histories of cities in the Maghreb, the Ottoman empire, and in Egypt, paying particular attention to Alexandria and Cairo. The cities founded along the Suez Canal upon the inception of its digging in 1859 have garnered some scholarly attention, but no historical inquiry yet exists of the role of mobile individuals in their history and in Egyptian history writ large. This dissertation traces the social and cultural history of Port Said between 1859, when it was founded as the Suez Canal’s northern harbor, and the onset of the twentieth century. It focuses on the role of migrants in influencing the formation of the Egyptian state. My documentary corpus is comprised of letters, petitions, consular court records, police files, the records of religious institutions, maps, and newspapers from thirty-five archives in Egypt, Malta, Italy, Great Britain, and France. The dissertation explores the every-day life of Port Said’s residents at a time of heightened migratory influx into the city. It demonstrates that the heterogeneous workforce who started moving to the isthmus of Suez in the 1850s opened up that area to commercial exploitation and political control. It also shows that, through their mundane, often contentious, encounters with local, consular, colonial, and Egyptian state authorities, the Egyptian and foreign newcomers who peopled the emerging town shaped norms and laws governing the use of the urban space, security, public hygiene, and morality. I conclude that law-making in modern Egypt was not merely the creation of bureaucrats in Cairo but also the work of transient individuals in an utterly new provincial port-city, one called into being by forces at once local and global. My research thus contributes to the histories of Egypt, of mobility in the Middle East, and of the relationship between capitals and ostensibly “peripheral” cities in times of urban transformations.

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