ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.
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Description
Random peptide microarrays are a powerful tool for both the treatment and diagnostics of infectious diseases. On the treatment side, selected random peptides on the microarray have either binding or lytic potency against certain pathogens cells, thus they can be synthesized into new antimicrobial agents, denoted as synbodies (synthetic antibodies). On the diagnostic side, serum containing specific infection-related antibodies create unique and distinct "pathogen-immunosignatures" on the random peptide microarray distinct from the healthy control serum, and this different mode of binding can be used as a more precise measurement than traditional ELISA tests. My thesis project is separated into these two parts: the first part falls into the treatment side and the second one focuses on the diagnostic side. My first chapter shows that a substitution amino acid peptide library helps to improve the activity of a recently reported synthetic antimicrobial peptide selected by the random peptide microarray. By substituting one or two amino acids of the original lead peptide, the new substitutes show changed hemolytic effects against mouse red blood cells and changed potency against two pathogens: Staphylococcus aureus and Pseudomonas aeruginosa. Two new substitutes are then combined together to form the synbody, which shows a significantly antimicrobial potency against Staphylococcus aureus (<0.5uM). In the second chapter, I explore the possibility of using the 10K Ver.2 random peptide microarray to monitor the humoral immune response of dengue. Over 2.5 billion people (40% of the world's population) live in dengue transmitting areas. However, currently there is no efficient dengue treatment or vaccine. Here, with limited dengue patient serum samples, we show that the immunosignature has the potential to not only distinguish the dengue infection from non-infected people, but also the primary dengue infection from the secondary dengue infections, dengue infection from West Nile Virus (WNV) infection, and even between different dengue serotypes. By further bioinformatic analysis, we demonstrate that the significant peptides selected to distinguish dengue infected and normal samples may indicate the epitopes responsible for the immune response.
ContributorsWang, Xiao (Author) / Johnston, Stephen Albert (Thesis advisor) / Blattman, Joseph (Committee member) / Arntzen, Charles (Committee member) / Arizona State University (Publisher)
Created2013
Description
Community college students are attracted to courses with alternative delivery formats such as hybrid courses because the more flexible delivery associated with such courses provides convenience for busy students. In a hybrid course, face-to-face, structured seat time is exchanged for online components. In such courses, students take more responsibility for their learning because they assume additional responsibility for learning more of the course material on their own. Thus, self-regulated learning (SRL) behaviors have the potential to be useful for students to successfully navigate hybrid courses because the online components require exercise of more personal control over the autonomous learning situations inherent in hybrid courses. Self-regulated learning theory includes three components: metacognition, motivation, and behavioral actions. In the current study, this theoretical framework is used to examine how inducing self-regulated learning activities among students taking a hybrid course influence performance in a community college science course. The intervention for this action research study consisted of a suite of activities that engage students in self-regulated learning behaviors to foster student performance. The specific SRL activities included predicting grades, reflections on coursework and study efforts in course preparation logs, explanation of SRL procedures in response to a vignette, photo ethnography work on their personal use of SRL approaches, and a personalized study plan. A mixed method approach was employed to gather evidence for the study. Results indicate that community college students use a variety of self-regulated learning strategies to support their learning of course material. Further, engaging community college students in learning reflection activities appears to afford some students with opportunities to refine their SRL skills and influence their learning. The discussion focuses on integrating the quantitative and qualitative data and explanation of the findings using the SRL framework. Additionally, lessons learned, limitations, and implications for practice and research are discussed. Specifically, it is suggested that instructors can foster student learning in hybrid courses by teaching students to engage in SRL processes and behaviors rather than merely focusing on delivery of course content. Such SRL behaviors allow students to exercise greater control over the autonomous learning situations inherent in hybrid courses.
ContributorsManuelito, Shannon Joy (Author) / Buss, Ray R. (Thesis advisor) / Smith, Rachel (Committee member) / Barnett, Joshua (Committee member) / Arizona State University (Publisher)
Created2013
Description
This study examined the experiences of first-generation college students who were enrolled in online degree programs at a traditional brick-and-mortar university located in the western United States. These students were viewed as "double first-generation" because they were not only the first in their family to pursue a bachelor's degree, but were also among the first generation in the history of American higher education to pursue public, postsecondary education in an entirely online format. The research was designed as a multiple methods case study that emphasized qualitative methods. Being exploratory in nature, the study focused on participant characteristics and the ways that they responded to and persisted in online degree programs. Data was collected through research that was conducted entirely online; it included an e-survey, two asynchronous focus groups, and individual interviews that were conducted via Skype. Grounded theory served as the primary method for data analysis, while quantitative descriptive statistics contextualized the case. The results of this study provide a window into the micro- and macro-level tensions at play in public, online postsecondary education. The findings indicate that these pioneering and traditionally underserved students drew from their diverse backgrounds to persist toward degree completion, overcoming challenges associated with time and finances, in hopes that their efforts would bring career and social mobility. As one of the first studies to critically examine the case of double first-generation college students, this study extends the literature in meaningful ways to provide valuable insights for policymakers, administrators, faculty, and staff who are involved with this population.
ContributorsShea, Jennifer Dawn (Author) / Fischman, Gustavo E. (Thesis advisor) / De Los Santos Jr, Alfredo G. (Committee member) / Ewing, Kris (Committee member) / Archambault, Leanna (Committee member) / Arizona State University (Publisher)
Created2013
Description
Biological diversity is threatened by increasing anthropogenic modification of natural environments and increasing demands on natural resources. Sonoran desert tortoises (Gopherus morafkai) currently have Candidate status under the Endangered Species Act (ESA) based on health and habitat threats. To ensure this animal persists in the midst of multiple threats requires an understanding of the life history and ecology of each population. I looked at one physiological and one behavioral aspect of a population of tortoises at the Sugarloaf Mountain (SL) study site in central Arizona, USA. I used 21 years of capture-recapture records to estimate growth parameters of the entire population. I investigated habitat selection of juvenile tortoises by selecting 117 locations of 11 tortoises that had been tracked by radio-telemetry one to three times weekly for two years, selecting locations from both summer active season and during winter hibernation. I compared 22 microhabitat variables of tortoise locations to random SL locations to determine habitat use and availability. Male tortoises at SL reach a greater asymptotic length than females, and males and females appear to grow at the same rate. Juvenile tortoises at the SL site use steep rocky hillsides with high proportions of sand and annual vegetation, few succulents, and enclosed shelters in summer. They use enclosed shelters on steep slopes for winter hibernation. An understanding of these features can allow managers to quantify Sonoran desert tortoise habitat needs and life history characteristics and to understand the impact of land use policies.
ContributorsBridges, Andrew (Author) / Bateman, Heather L (Thesis advisor) / Miller, William (Committee member) / Ulrich, Jon (Committee member) / Arizona State University (Publisher)
Created2012
Description
At the heart of every eusocial insect colony is a reproductive division of labor. This division can emerge through dominance interactions at the adult stage or through the production of distinct queen and worker castes at the larval stage. In both cases, this division depends on plasticity within an individual to develop reproductive characteristics or serve as a worker. In order to gain insight into the evolution of reproductive plasticity in the social insects, I investigated caste determination and dominance in the ant Harpegnathos saltator, a species that retains a number of ancestral characteristics. Treatment of worker larvae with a juvenile hormone (JH) analog induced late-instar larvae to develop as queens. At the colony level, workers must have a mechanism to regulate larval development to prevent queens from developing out of season. I identified a new behavior in H. saltator where workers bite larvae to inhibit queen determination. Workers could identify larval caste based on a chemical signal specific to queen-destined larvae, and the production of this signal was directly linked to increased JH levels. This association provides a connection between the physiological factors that induce queen development and the production of a caste-specific larval signal. In addition to caste determination at the larval stage, adult workers of H. saltator compete to establish a reproductive hierarchy. Unlike other social insects, dominance in H. saltator was not related to differences in JH or ecdysteroid levels. Instead, changes in brain levels of biogenic amines, particularly dopamine, were correlated with dominance and reproductive status. Receptor genes for dopamine were expressed in both the brain and ovaries of H. saltator, and this suggests that dopamine may coordinate changes in behavior at the neurological level with ovarian status. Together, these studies build on our understanding of reproductive plasticity in social insects and provide insight into the evolution of a reproductive division of labor.
ContributorsPenick, Clint A (Author) / Liebig, Jürgen (Thesis advisor) / Brent, Colin (Committee member) / Gadau, Jürgen (Committee member) / Hölldobler, Bert (Committee member) / Rutowski, Ron (Committee member) / Arizona State University (Publisher)
Created2012
Description
In somatic cells, the mitotic spindle apparatus is centrosomal and several isoforms of Protein Kinase C (PKC) have been associated with the mitotic spindle, but their role in stabilizing the mitotic spindle is unclear. Other protein kinases such as, Glycogen Synthase Kinase 3â (GSK3â) also have been shown to be associated with the mitotic spindle. In the study in chapter 2, we show the enrichment of active (phosphorylated) PKCæ at the centrosomal region of the spindle apparatus in metaphase stage of 3T3 cells. In order to understand whether the two kinases, PKC and GSK3â are associated with the mitotic spindle, first, the co-localization and close molecular proximity of PKC isoforms with GSK3â was studied in metaphase cells. Second, the involvement of inactive GSK3â in maintaining an intact mitotic spindle was shown. Third, this study showed that addition of a phospho-PKCæ specific inhibitor to cells can disrupt the mitotic spindle microtubules. The mitotic spindle at metaphase in mouse fibroblasts appears to be maintained by PKCæ acting through GSK3â. The MAPK pathway has been implicated in various functions related to cell cycle regulation. MAPKK (MEK) is part of this pathway and the extracellular regulated kinase (ERK) is its known downstream target. GSK3â and PKCæ also have been implicated in cell cycle regulation. In the study in chapter 3, we tested the effects of inhibiting MEK on the activities of ERK, GSK3â, PKCæ, and á-tubulin. Results from this study indicate that inhibition of MEK did not inhibit GSK3â and PKCæ enrichment at the centrosomes. However, the mitotic spindle showed a reduction in the pixel intensity of microtubules and also a reduction in the number of cells in each of the M-phase stages. A peptide activation inhibitor of ERK was also used. Our results indicated a decrease in mitotic spindle microtubules and an absence of cells in most of the M-phase stages. GSK3â and PKCæ enrichment were however not inhibited at the centrosomes. Taken together, the kinases GSK3â and PKCæ may not function as a part of the MAPK pathway to regulate the mitotic spindle.
ContributorsChakravadhanula, Madhavi (Author) / Capco, David G. (Thesis advisor) / Chandler, Douglas (Committee member) / Clark-Curtiss, Josephine (Committee member) / Newfeld, Stuart (Committee member) / Arizona State University (Publisher)
Created2012
Description
Immigration status and educational opportunities are at the forefront of the current national conversation regarding "DREAMers": children of immigrants brought to the United States at a young age who lack legal status but are raised and educated in the American system. In 2006, Arizona voters passed Proposition 300, in part prohibiting in-state tuition for state colleges and universities to individuals who cannot provide proof of citizenship or legal residency. For those DREAMers who hoped to attend college following high school, this policy affected their ability to enroll because of the increased tuition and lack of eligibility for state-sponsored financial aid. This law's impact is also present in Arizona's public high schools. High schools, in partnership with community colleges, have created a robust system of dual or concurrent enrollment courses: college classes offered to high school students as a means of accelerating their learning. In this arrangement, full payments for tuition are required by families or by the programs that support the students, creating a system in public schools where some students are able to participate while others cannot due to their residency status. The aim of this study was to determine the educational, social, and emotional effects of Proposition 300 upon undocumented secondary students. Through qualitative analysis, this study relies upon focus group interviews with high school graduates impacted by Proposition 300 before graduation. Interviews were also conducted with parents and with educators representing both secondary and higher education. A total of nine students, two parents, and four education professionals participated in semi-structured conversations over the course of several months in the fall of 2012. The data was collected, analyzed, and coded, extrapolating common themes related to the review of literature and information from the participants. The findings describe the effects Proposition 300 has had as it pertains to undocumented students, their experience of their unequal access to dual or concurrent enrollment, the disconnect they have felt from their "documented" peers, and the emotional impact they have felt as a result of this law. Among the findings, the potential impact of Deferred Action for Childhood Arrivals (DACA), enacted in August 2012, is explored.
ContributorsLaurin, Joel (Author) / Barnett, Joshua (Thesis advisor) / Heck, Thomas (Thesis advisor) / Langley, Janet (Committee member) / Arizona State University (Publisher)
Created2013
Description
The purpose of this study was to investigate whether an alignment exists between the mission of Puente de Hozho Magnet School and the visualization of how current Navajo students view their education at the school. Qualitative research was used as an opportunity to explore the significance and to gain an in-depth understanding of how Navajo students view their education in the context of their personal experiences. The population consisted of six Navajo fifth grade students who lived outside the boundaries of their Indian reservation and attended school at Puente de Hozho Magnet School. The six student participants were asked to respond to the question, "What does your education look like at Puente de Hozho Magnet School?" through the pictures they took with a camera in and around the school. After the pictures were developed, students were individually interviewed by utilizing selected pictures to prompt their memory in eliciting descriptions and meanings of the images they captured. The students' responses generated a data set for coding and analysis, from which a wealth of data yielded prominent themes as to their education at Puente de Hozho Magnet School. Analysis of this research concluded that the students' visualization of their education at Puente de Hozho is aligned with the original mission and vision of the school. The student voices represent a relationship of natural connections to their cultural heritage as experienced in their school by disregarding stereotypes and rising above the expected.
ContributorsYazzie, Lamont L (Author) / Spencer, Dee Ann (Thesis advisor) / Appleton, Nicholas A (Committee member) / Gilmore, Treva C (Committee member) / Arizona State University (Publisher)
Created2012
Description
This study examined the intended and unintended consequences associated with the Education Value-Added Assessment System (EVAAS) as perceived and experienced by teachers in the Houston Independent School District (HISD). To evaluate teacher effectiveness, HISD is using EVAAS for high-stakes consequences more than any other district or state in the country. A large-scale electronic survey was used to investigate the model's reliability and validity; to determine whether teachers used the EVAAS data in formative ways as intended; to gather teachers' opinions on EVAAS's claimed benefits and statements; and to understand the unintended consequences that occurred as a result of EVAAS use in HISD. Mixed methods data collection and analyses were used to present the findings in user-friendly ways, particularly when using the words and experiences of the teachers themselves. Results revealed that the reliability of the EVAAS model produced split and inconsistent results among teacher participants, and teachers indicated that students biased the EVAAS results. The majority of teachers did not report similar EVAAS and principal observation scores, reducing the criterion-related validity of both measures of teacher quality. Teachers revealed discrepancies in the distribution of EVAAS reports, the awareness of trainings offered, and among principals' understanding of EVAAS across the district. This resulted in an underwhelming number of teachers who reportedly used EVAAS data for formative purposes. Teachers disagreed with EVAAS marketing claims, implying the majority did not believe EVAAS worked as intended and promoted. Additionally, many unintended consequences associated with the high-stakes use of EVAAS emerged through teachers' responses, which revealed among others that teachers felt heightened pressure and competition, which reduced morale and collaboration, and encouraged cheating or teaching to the test in attempt to raise EVAAS scores. This study is one of the first to investigate how the EVAAS model works in practice and provides a glimpse of whether value-added models might produce desired outcomes and encourage best teacher practices. This is information of which policymakers, researchers, and districts should be aware and consider when implementing the EVAAS, or any value-added model for teacher evaluation, as many of the reported issues are not specific to the EVAAS model.
ContributorsCollins, Clarin (Author) / Amrein-Beardsley, Audrey (Thesis advisor) / Berliner, David C. (Committee member) / Fischman, Gustavo E (Committee member) / Arizona State University (Publisher)
Created2012
Description
Infertility has become an increasing problem in developed countries and in many cases can be attributed to compromised sperm quality. Assessment of male fertility typically utilizes semen analysis which mainly examines sperm morphology, however many males whose sperm appear normal are sub- or infertile, suggesting that sperm from these males may be deficient in a protein or suite of proteins. To date, very little is known about the composition of sperm or the complex maturation process that confers motility and fertilization competency to sperm. Chapter 1 discusses the use of whole cell mass spectrometry to identify 1247 proteins comprising the Rhesus macaque (Macaca mulatta) sperm proteome, a commonly used model of human reproduction. This study provides a more robust proxy of human sperm composition than was previously available and facilitates studies of sperm using the rhesus macaque as a model. Chapters 2 & 3 provide a systems level overview of changes in sperm proteome composition that occurs during epididymal transit. Chapter 2 reports the proteomes of sperm collected from the caput, corpus and cauda segments of the mouse epididymis, identifying 1536, 1720 and 1234 proteins respectively. Chapter 3 reports the sperm proteome from four distinct segments of the Rhesus macaque epididymis, including the caput, proximal corpus, distal corpus and cauda, identifying 1951, 2014, 1764 and 1423 proteins respectively. These studies identify a number of proteins that are added and removed from sperm during epididymal transit which likely play an important role in the sperm maturation process. To date no comparative evolutionary studies of sperm proteomes have been undertaken. Chapter 4 compares four mammalian sperm proteomes including the human, macaque, mouse and rat. This study identified 98 proteins common to all four sperm proteomes, 82 primate and 90 rodent lineage-specific proteins and 494, 467, 566, and 193 species specific proteins in the human, macaque, mouse and rat sperm proteomes respectively and discusses how differences in sperm composition may ultimately lead to functional differences across species. Finally, chapter 5 uses sperm proteome data to inform the preliminary design of a rodent contraceptive vaccine delivered orally using recombinant attenuated Salmonella vaccine vectors.
ContributorsSkerget, Sheri Jo (Author) / Karr, Timothy L. (Thesis advisor) / Lake, Douglas (Committee member) / Petritis, Konstantinos (Committee member) / Arizona State University (Publisher)
Created2013