Theses and Dissertations
This collection includes both ASU Theses and Dissertations, submitted by graduate students, and the Barrett, Honors College theses submitted by undergraduate students.
Displaying 1 - 10 of 130
Description
Interior design continues to re-define itself as a discipline that presents designers with new problems that require innovative solutions. This is particularly true in the case in office design. The transformation of the office environment from the standard bullpen configuration to today's dynamic, flexible, and open floor plans has required new design methodologies that incorporate tools and technologies that are readily available to interior designers. Today, increased use of teams in the workplace challenges interior designers to create environments that accommodate both group and individual tasks (Brill, Weidermann & BOSTI associates, 2001). Collaboration has received considerable attention as organizations focus on productivity and reducing costs to compete in a global economy (Hassanain, 2006). Designers and architects should learn to create environments that respond to dynamic, moveable, and flexible work methods. This web-based research study explores the use of pattern language as a new tool for designing collaborative work environments. In 1977, Christopher Alexander and his associates developed `Pattern language' (Alexander, Ishikawa & Silverstein, 1977) as a design formulation methodology. It consists of a series of interrelated physical elements combined to create a framework for design solutions. This pattern language tool for collaborative work environments was created based on research by Lori Anthony (2001). This study further builds upon current trends and research in collaborative work environments. The researcher conducted a pilot test by sending the web-based tool and an online questionnaire to all graduate students and faculty members in the fields of interior design and healthcare and healing environment (HHE). After testing its validity in The Design School at Arizona State University, the same tool and questionnaire was sent to the employees of one of the leading architecture and interior design firms in Phoenix, AZ. The results showed that among those design professionals surveyed, the majority believe pattern language could be a valuable design tool. The insights obtained from this study will provide designers, architects, and facility managers with a new design tool to aid in creating effective collaborative spaces in a work environment.
ContributorsSangoi, Deepika (Author) / Bender, Diane (Thesis advisor) / Brandt, Beverly (Committee member) / Heywood, William (Committee member) / Arizona State University (Publisher)
Created2011
Description
The concept of vaccination dates back further than Edward Jenner's first vaccine using cowpox pustules to confer immunity against smallpox in 1796. Nevertheless, it was Jenner's success that gave vaccines their name and made vaccinia virus (VACV) of particular interest. More than 200 years later there is still the need to understand vaccination from vaccine design to prediction of vaccine efficacy using mathematical models. Post-exposure vaccination with VACV has been suggested to be effective if administered within four days of smallpox exposure although this has not been definitively studied in humans. The first and second chapters analyze post-exposure prophylaxis of VACV in an animal model using v50ΔB13RMγ, a recombinant VACV expressing murine interferon gamma (IFN-γ) also known as type II IFN. While untreated animals infected with wild type VACV die by 10 days post-infection (dpi), animals treated with v50ΔB13RMγ 1 dpi had decreased morbidity and 100% survival. Despite these differences, the viral load was similar in both groups suggesting that v50ΔB13RMγ acts as an immunoregulator rather than as an antiviral. One of the main characteristics of VACV is its resistance to type I IFN, an effect primarily mediated by the E3L protein, which has a Z-DNA binding domain and a double-stranded RNA (dsRNA) binding domain. In the third chapter a VACV that independently expresses both domains of E3L was engineered and compared to wild type in cells in culture. The dual expression virus was unable to replicate in the JC murine cell line where both domains are needed together for replication. Moreover, phosphorylation of the dsRNA dependent protein kinase (PKR) was observed at late times post-infection which indicates that both domains need to be linked together in order to block the IFN response. Because smallpox has already been eradicated, the utility of mathematical modeling as a tool for predicting disease spread and vaccine efficacy was explored in the last chapter using dengue as a disease model. Current modeling approaches were reviewed and the 2000-2001 dengue outbreak in a Peruvian region was analyzed. This last section highlights the importance of interdisciplinary collaboration and how it benefits research on infectious diseases.
ContributorsHolechek, Susan A (Author) / Jacobs, Bertram L (Thesis advisor) / Castillo-Chavez, Carlos (Committee member) / Frasch, Wayne (Committee member) / Hogue, Brenda (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2011
Description
HIV/AIDS is the sixth leading cause of death worldwide and the leading cause of death among women of reproductive age living in low-income countries. Clinicians in industrialized nations monitor the efficacy of antiretroviral drugs and HIV disease progression with the HIV-1 viral load assay, which measures the copy number of HIV-1 RNA in blood. However, viral load assays are not widely available in sub-Saharan Africa and cost between 50-$139 USD per test on average where available. To address this problem, a mixed-methods approach was undertaken to design a novel and inexpensive viral load diagnostic for HIV-1 and to evaluate barriers to its adoption in a developing country. The assay was produced based on loop-mediated isothermal amplification (LAMP). Blood samples from twenty-one individuals were spiked with varying concentrations of HIV-1 RNA to evaluate the sensitivity and specificity of LAMP. Under isothermal conditions, LAMP was performed with an initial reverse-transcription step (RT-LAMP) and primers designed for HIV-1 subtype C. Each reaction generated up to a few billion copies of target DNA within an hour. Presence of target was detected through naked-eye observation of a fluorescent indicator and verified by DNA gel electrophoresis and real-time fluorescence. The assay successfully detected the presence of HIV in samples with a broad range of HIV RNA concentration, from over 120,000 copies/reaction to 120 copies/reaction. In order to better understand barriers to adoption of LAMP in developing countries, a feasibility study was undertaken in Tanzania, a low-income country facing significant problems in healthcare. Medical professionals in Northern Tanzania were surveyed for feedback regarding perspectives of current HIV assays, patient treatment strategies, availability of treatment, treatment priorities, HIV transmission, and barriers to adoption of the HIV-1 LAMP assay. The majority of medical providers surveyed indicated that the proposed LAMP assay is too expensive for their patient populations. Significant gender differences were observed in response to some survey questions. Female medical providers were more likely to cite stigma as a source problem of the HIV epidemic than male medical providers while males were more likely to cite lack of education as a source problem than female medical providers.
ContributorsSalamone, Damien Thomas (Author) / Jacobs, Bertram L (Thesis advisor) / Marsiglia, Flavio (Committee member) / Stout, Valerie (Committee member) / Johnson, Crista (Committee member) / Arizona State University (Publisher)
Created2011
Description
Rhodoferax antarcticus strain ANT.BR, a purple nonsulfur bacterium isolated from a microbial mat in Ross Island, Antarctica, is the first described anoxygenic phototrophic bacterium that is adapted to cold habitats and is the first beta-proteobacterium to undergo complete genome sequencing. R. antarcticus has unique absorption spectra and there are no obvious intracytoplasmic membranes in cells grown phototrophically, even under low light intensity. Analysis of the finished genome sequence reveals a single chromosome (3,809,266 bp) and a large plasmid (198,615 bp) that together harbor 4,262 putative genes. The genome contains two types of Rubiscos, Form IAq and Form II, which are known to exhibit quite different kinetic properties in other bacteria. The presence of multiple Rubisco forms could give R. antarcticus high metabolic flexibility in diverse environments. Annotation of the complete genome sequence along with previous experimental results predict the presence of structural genes for three types of light-harvesting (LH) complexes, LH I (B875), LH II (B800/850), and LH III (B800/820). There is evidence that expression of genes for the LH II complex might be inhibited when R. antarcticus is under low temperature and/or low light intensity. These interesting condition-dependent light-harvesting apparatuses and the control of their expression are very valuable for the further understanding of photosynthesis in cold environments. Finally, R. antarcticus exhibits a highly motile lifestyle. The genome content and organization of all putative polar flagella genes are characterized and discussed.
ContributorsZhao, Tingting, M.S (Author) / Touchman, Jeffrey (Thesis advisor) / Rosenberg, Michael (Committee member) / Redding, Kevin (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2011
Description
The oceans play an essential role in global biogeochemical cycles and in regulating climate. The biological carbon pump, the photosynthetic fixation of carbon dioxide by phytoplankton and subsequent sequestration of organic carbon into deep water, combined with the physical carbon pump, make the oceans the only long-term net sink for anthropogenic carbon dioxide. A full understanding of the workings of the biological carbon pump requires a knowledge of the role of different taxonomic groups of phytoplankton (protists and cyanobacteria) to organic carbon export. However, this has been difficult due to the degraded nature of particles sinking into particle traps, the main tools employed by oceanographers to collect sinking particulate matter in the ocean. In this study DNA-based molecular methods, including denaturing gradient gel electrophoresis, cloning and sequencing, and taxon-specific quantitative PCR, allowed for the first time for the identification of which protists and cyanobacteria contributed to the material collected by the traps in relation to their presence in the euphotic zone. I conducted this study at two time-series stations in the subtropical North Atlantic Ocean, one north of the Canary Islands, and one located south of Bermuda. The Bermuda study allowed me to investigate seasonal and interannual changes in the contribution of the plankton community to particle flux. I could also show that small unarmored taxa, including representatives of prasinophytes and cyanobacteria, constituted a significant fraction of sequences recovered from sediment trap material. Prasinophyte sequences alone could account for up to 13% of the clone library sequences of trap material during bloom periods. These observations contradict a long-standing paradigm in biological oceanography that only large taxa with mineral shells are capable of sinking while smaller, unarmored cells are recycled in the euphotic zone through the microbial loop. Climate change and a subsequent warming of the surface ocean may lead to a shift in the protist community toward smaller cell size in the future, but in light of these findings these changes may not necessarily lead to a reduction in the strength of the biological carbon pump.
ContributorsAmacher, Jessica (Author) / Neuer, Susanne (Thesis advisor) / Garcia-Pichel, Ferran (Committee member) / Lomas, Michael (Committee member) / Wojciechowski, Martin (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2011
Description
Pathogenic Gram-negative bacteria employ a variety of molecular mechanisms to combat host defenses. Two-component regulatory systems (TCR systems) are the most ubiquitous signal transduction systems which regulate many genes required for virulence and survival of bacteria. In this study, I analyzed different TCR systems in two clinically-relevant Gram-negative bacteria, i.e., oral pathogen Porphyromonas gingivalis and enterobacterial Escherichia coli. P. gingivalis is a major causative agent of periodontal disease as well as systemic illnesses, like cardiovascular disease. A microarray study found that the putative PorY-PorX TCR system controls the secretion and maturation of virulence factors, as well as loci involved in the PorSS secretion system, which secretes proteinases, i.e., gingipains, responsible for periodontal disease. Proteomic analysis (SILAC) was used to improve the microarray data, reverse-transcription PCR to verify the proteomic data, and primer extension assay to determine the promoter regions of specific PorX regulated loci. I was able to characterize multiple genetic loci regulated by this TCR system, many of which play an essential role in hemagglutination and host-cell adhesion, and likely contribute to virulence in this bacterium. Enteric Gram-negative bacteria must withstand many host defenses such as digestive enzymes, low pH, and antimicrobial peptides (AMPs). The CpxR-CpxA TCR system of E. coli has been extensively characterized and shown to be required for protection against AMPs. Most recently, this TCR system has been shown to up-regulate the rfe-rff operon which encodes genes involved in the production of enterobacterial common antigen (ECA), and confers protection against a variety of AMPs. In this study, I utilized primer extension and DNase I footprinting to determine how CpxR regulates the ECA operon. My findings suggest that CpxR modulates transcription by directly binding to the rfe promoter. Multiple genetic and biochemical approaches were used to demonstrate that specific TCR systems contribute to regulation of virulence factors and resistance to host defenses in P. gingivalis and E. coli, respectively. Understanding these genetic circuits provides insight into strategies for pathogenesis and resistance to host defenses in Gram negative bacterial pathogens. Finally, these data provide compelling potential molecular targets for therapeutics to treat P. gingivalis and E. coli infections.
ContributorsLeonetti, Cori (Author) / Shi, Yixin (Thesis advisor) / Stout, Valerie (Committee member) / Nickerson, Cheryl (Committee member) / Sandrin, Todd (Committee member) / Arizona State University (Publisher)
Created2013
Description
The study of lighting design has important implications for consumer behavior and is an important aspect of consideration for the retail industry. In today's global economy consumers can come from a number of cultural backgrounds. It is important to understand various cultures' perceptions of lighting design in order for retailers to better understand how to use lighting as a benefit to provide consumers with a desirable shopping experience. This thesis provides insight into the effects of ambient lighting on product perception among Americans and Middle Easterners. Both cultural groups' possess significant purchasing power in the worldwide market place. This research will allow marketers, designers and consumers a better understanding of how culture may play a role in consumer perceptions and behavior Results of this study are based on data gathered from 164 surveys from individuals of American and Middle Eastern heritage. Follow up interviews were also conducted to examine the nuances of product perception and potential differences across cultures. This study, using qualitative and quantitative methods, was executed using a Sequential Explanatory Strategy. Survey data were analyzed to uncover significant correlations and relationships using measures of descriptive analysis, analysis of variance (ANOVA), and regression analysis. Interviews were analyzed using theme-based coding and reported in narrative form. The results suggest that lighting does in fact have an impact on product perception, however despite minor differences, this perception does not vary much between individuals from American and Middle Eastern cultures. It was found that lighting could affect price and quality perception with reference to store-image and store atmospherics. Additionally, lighting has a higher impact on subjective impressions of product (such as Freshness, Pleasantness, and Attractiveness), more than Price and Quality perceptions. This study suggests that particular lighting characteristics could be responsible for differences in product perception between these two cultures. This is important to note for lighting designers and marketers to create retail atmospheres that are preferable to both cultures.
ContributorsAlsharhan, Dalal Anwar (Author) / Kroelinger, Michael D. (Thesis advisor) / Eaton, John (Committee member) / Heywood, William (Committee member) / Arizona State University (Publisher)
Created2013
Description
A growing body of research shows that characteristics of the built environment in healthcare facilities impact patients' well-being. Research findings suggest that patients form judgments of perceived quality care based on environmental characteristics. Patient outcomes and ratings of quality of care are linked to the environments' ability to reduce patient stress as well as influence perceptions of quality of care. Historically, this research has been focused in the hospital environment. The United States healthcare system heavily relies on hospitals to treat (rather than prevent) illness, leading to a high per capita healthcare expenditure. Currently, this healthcare system is shifting to rely heavily on ambulatory care settings and primary care providers to detect, prevent, and manage expensive medical conditions. The highest rates of preventable disease and the lowest rates of primary care usage are found in the young adult population (ages 18 to 24). More than any other patient population, this segment rates their satisfaction with healthcare significantly low. For this population education, early detection, and monitoring will be key for a primary care focused model to have the greatest impact on care and long-term savings. Strong patient-physician connections ensure the success of a primary care focused model. The physical environment has the opportunity to provide a message consistent with a physician's practice values and goals. Environmental cues in the waiting area have the potential to relay these messages to the patient prior to physician contact. Through an understanding and optimization of these cues patient perception of quality of care may be increased, thus improving the patient-physician relationship. This study provides insight on how to optimize environmental impact on the healthcare experience. This descriptive exploratory study utilized a non-verbal self-report instrument to collect demographic information and measure participant's responses to two panoramic photos of primary care provider waiting areas. Respondents were asked to identify physical elements in the photos that contributed to their perceptions of the quality of care to be expected. The sample population consisted of 33, 18 to 24 year-olds leaving a total of 234 emotional markers and comments. Qualitative and quantitative revealed three key themes of appeal, comfort, and regard. Physical elements, in the photos, related to the themes include: General areas that were important to the respondents were the seating and reception areas, as well as the overall appearance of the waiting area. Key elements identified to be significant characteristics influencing perceptions of quality of care are presented in this study.
ContributorsBadura, Kerri (Author) / Lamb, Gerri (Thesis advisor) / Heywood, William (Committee member) / Wolf, Peter (Committee member) / Arizona State University (Publisher)
Created2012
Description
The study of bacterial resistance to antimicrobial peptides (AMPs) is a significant area of interest as these peptides have the potential to be developed into alternative drug therapies to combat microbial pathogens. AMPs represent a class of host-mediated factors that function to prevent microbial infection of their host and serve as a first line of defense. To date, over 1,000 AMPs of various natures have been predicted or experimentally characterized. Their potent bactericidal activities and broad-based target repertoire make them a promising next-generation pharmaceutical therapy to combat bacterial pathogens. It is important to understand the molecular mechanisms, both genetic and physiological, that bacteria employ to circumvent the bactericidal activities of AMPs. These understandings will allow researchers to overcome challenges posed with the development of new drug therapies; as well as identify, at a fundamental level, how bacteria are able to adapt and survive within varied host environments. Here, results are presented from the first reported large scale, systematic screen in which the Keio collection of ~4,000 Escherichia coli deletion mutants were challenged against physiologically significant AMPs to identify genes required for resistance. Less than 3% of the total number of genes on the E. coli chromosome was determined to contribute to bacterial resistance to at least one AMP analyzed in the screen. Further, the screen implicated a single cellular component (enterobacterial common antigen, ECA) and a single transporter system (twin-arginine transporter, Tat) as being required for resistance to each AMP class. Using antimicrobial resistance as a tool to identify novel genetic mechanisms, subsequent analyses were able to identify a two-component system, CpxR/CpxA, as a global regulator in bacterial resistance to AMPs. Multiple previously characterized CpxR/A members, as well as members found in this study, were identified in the screen. Notably, CpxR/A was found to transcriptionally regulate the gene cluster responsible for the biosynthesis of the ECA. Thus, a novel genetic mechanism was uncovered that directly correlates with a physiologically significant cellular component that appears to globally contribute to bacterial resistance to AMPs.
ContributorsWeatherspoon-Griffin, Natasha (Author) / Shi, Yixin (Thesis advisor) / Clark-Curtiss, Josephine (Committee member) / Misra, Rajeev (Committee member) / Nickerson, Cheryl (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2013
Description
This dissertation explores the role of smart home service provisions (SHSP) as motivational agents supporting goal attainment and human flourishing. Evoking human flourishing as a lens for interaction encapsulates issues of wellbeing, adaptation and problem solving within the context of social interaction. To investigate this line of research a new, motivation-sensitive approach to design was implemented. This approach combined psychometric analysis from motivational psychology's Personal Project Analysis (PPA) and Place Attachment theory's Sense of Place (SoP) analysis to produce project-centered motivational models for environmental congruence. Regression analysis of surveys collected from 150 (n = 150) young adults about their homes revealed PPA motivational dimensions had significant main affects on all three SoP factors. Model one indicated PPA dimensions Fearful and Value Congruency predicted the SoP factor Place Attachment (p = 0.012). Model two indicated the PPA factor Positive Affect and PPA dimensions Value Congruency, Self Identity and Autonomy predicted Place Identity (p = .0003). Model three indicated PPA dimensions Difficulty and Likelihood of Success predicted the SoP factor Place Dependency. The relationships between motivational PPA dimensions and SoP demonstrated in these models informed creation of a set of motivational design heuristics. These heuristics guided 20 participants (n = 20) through co-design of paper prototypes of SHSPs supporting goal attainment and human flourishing. Normative analysis of these paper prototypes fashioned a design framework consisting of the use cases "make with me", "keep me on task" and "improve myself"; the four design principles "time and timing", "guidance and accountability", "project ambiguity" and "positivity mechanisms"; and the seven interaction models "structuring time", "prompt user", "gather resources", "consume content", "create content", "restrict and/or restore access to content" and "share content". This design framework described and evaluated three technology probes installed in the homes of three participants (n = 3) for field-testing over the course of one week. A priori and post priori samples of psychometric measures were inconclusive in determining if SHSP motivated goal attainment or increased environmental congruency between young adults and their homes.
ContributorsBrotman, Ryan Scott (Author) / Burleson, Winsow (Thesis advisor) / Heywood, William (Committee member) / Forlizzi, Jodi (Committee member) / Arizona State University (Publisher)
Created2013