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
Cell adhesion is an important aspect of many biological processes. The atomic force microscope (AFM) has made it possible to quantify the forces involved in cellular adhesion using a technique called single cell force spectroscopy (SCFS). AFM based SCFS offers versatile control over experimental conditions for probing directly the interaction between specific cell types and specific proteins, surfaces, or other cells. Transmembrane integrins are the primary proteins involved in cellular adhesion to the extra cellular matix (ECM). One of the chief integrins involved in the adhesion of leukocyte cells is αMβ2 (Mac-1). The experiments in this dissertation quantify the adhesion of Mac-1 expressing human embryonic kidney (HEK Mac-1), platelets, and neutrophils cells on substrates with different concentrations of fibrinogen and on fibrin gels and multi-layered fibrinogen coated fibrin gels. It was shown that multi-layered fibrinogen reduces the adhesion force of these cells considerably. A novel method was developed as part of this research combining total internal reflection microscopy (TIRFM) with SCFS allowing for optical microscopy of HEK Mac-1 cells interacting with bovine serum albumin (BSA) coated glass after interacting with multi-layered fibrinogen. HEK Mac-1 cells are able to remove fibrinogen molecules from the multi-layered fibrinogen matrix. An analysis methodology for quantifying the kinetic parameters of integrin-ligand interactions from SCFS experiments is proposed, and the kinetic parameters of the Mac-1 fibrinogen bond are quantified. Additional SCFS experiments quantify the adhesion of macrophages and HEK Mac-1 cells on functionalized glass surfaces and normal glass surfaces. Both cell types show highest adhesion on a novel functionalized glass surface that was prepared to induce macrophage fusion. These experiments demonstrate the versatility of AFM based SCFS, and how it can be applied to address many questions in cellular biology offering quantitative insights.
ContributorsChristenson, Wayne B (Author) / Ros, Robert (Thesis advisor) / Beckstein, Oliver (Committee member) / Lindsay, Stuart (Committee member) / Ugarova, Tatiana (Committee member) / Arizona State University (Publisher)
Created2016
Description
A dental exam in twenty-first century America generally includes the taking of radiographs, which are x-ray images of the mouth. These images allow dentists to see structures below the gum line and within the teeth. Having a patient's radiographs on file has become a dental standard of care in many states, but x-rays were only discovered a little over 100 years ago. This research analyzes how and why the x-ray image has become a ubiquitous tool in the dental field. Primary literature written by dentists and scientists of the time shows that the x-ray was established in dentistry by the 1950s. Therefore, this thesis tracks the changes in x-ray technological developments, the spread of information and related safety concerns between 1890 and 1955. X-ray technology went from being an accidental discovery to a device commonly purchased by dentists. X-ray information started out in the form of the anecdotes of individuals and led to the formation of large professional groups. Safety concerns of only a few people later became an important facet of new devices. These three major shifts are described by looking at those who prompted the changes; they fall into the categories of people, technological artifacts and institutions. The x-ray became integrated into dentistry as a product of the work of people such as C. Edmund Kells, a proponent of dental x-rays, technological improvements including faster film speed, and the influence of institutions such as Victor X-Ray Company and the American Dental Association. These changes that resulted established a strong foundation of x-ray technology in dentistry. From there, the dental x-ray developed to its modern form.
ContributorsMartinez, Britta (Author) / Ellison, Karin (Thesis advisor) / Maienschein, Jane (Thesis advisor) / Hurlbut, Ben (Committee member) / Arizona State University (Publisher)
Created2013
Description
Emerging pathogens present several challenges to medical diagnostics. Primarily, the exponential spread of a novel pathogen through naïve populations require a rapid and overwhelming diagnostic response at the site of outbreak. While point-of-care (PoC) platforms have been developed for detection of antigens, serologic responses, and pathogenic genomes, only nucleic acid diagnostics currently have the potential to be developed and manufactured within weeks of an outbreak owing to the speed of next-generation sequencing and custom DNA synthesis. Among nucleic acid diagnostics, isothermal amplification strategies are uniquely suited for PoC implementation due to their simple instrumentation and lack of thermocycling requirement. Unfortunately, isothermal strategies are currently prone to spurious nonspecific amplification, hindering their specificity and necessitating extensive empirical design pipelines that are both time and resource intensive. In this work, isothermal amplification strategies are extensively compared for their feasibility of implementation in outbreak response scenarios. One such technology, Loop-mediated Amplification (LAMP), is identified as having high-potential for rapid development and PoC deployment. Various approaches to abrogating nonspecific amplification are described including a novel in silico design tool based on coarse-grained simulation of interactions between thermophilic DNA polymerase and DNA strands in isothermal reaction conditions. Nonspecific amplification is shown to be due to stabilization of primer secondary structures by high concentrations of Bst DNA polymerase and a mechanism of micro-complement-mediated cross-priming is demonstrated as causal via nanopore sequencing of nonspecific reaction products. The resulting computational model predicts primer set background in 64% of 67 test assays and its usefulness is illustrated further by determining problematic primers in a West Nile Virus-specific LAMP primer set and optimizing primer 3’ nucleotides to eliminate micro-complements within the reaction, resulting in inhibition of background accumulation. Finally, the emergence of Orthopox monkeypox (MPXV) as a recurring threat is discussed and SimCycle is utilized to develop a novel technique for clade-specific discrimination of MPXV based on bridging viral genomic rearrangements (Bridging LAMP). Bridging LAMP is implemented in a 4-plex microfluidic format and demonstrates 100% sensitivity in detection of 100 copies of viral lysates and 45 crude MPXV-positive patient samples collected during the 2022 Clade IIb outbreak.
ContributorsKnappenberger, Mark Daniel (Author) / Anderson, Karen S (Thesis advisor) / LaBaer, Joshua (Committee member) / Roberson, Robert (Committee member) / Lindsay, Stuart (Committee member) / Arizona State University (Publisher)
Created2023
Description
In the US, menstrual education, which provides key information about menstrual hygiene and health to both young girls and boys, historically lacks biologically accurate information about the menstrual cycle and perpetuates harmful perceptions about female reproductive health. When people are unable to differentiate between normal and abnormal menstrual bleeding, based on a lack of quality menstrual education, common gynecological conditions often remain underreported. This raises a question as to how girls’ menstrual education experiences influence the ways in which they perceive normal menstrual bleeding and seek treatment for common abnormalities, such as heavy, painful, or irregular menstrual bleeding. A mixed methods approach allowed evaluation of girls’ abilities to recognize abnormal menstrual bleeding. A literature review established relevant historical and social context on the prevalence and quality of menstrual education in the US. Then, five focus groups, each including five to eight college-aged women, totaling thirty-three participants, allowed for macro-level analysis of current challenges and gaps in knowledge related to menstruation. To better examine the relationship between menstrual education and reproductive health outcomes, twelve semi-structured, one-on-one interviews allowed micro-level analysis. Those interviews consisted of women diagnosed with endometriosis and polycystic ovary syndrome, common gynecological conditions that include abnormal menstrual bleeding. Developing a codebook of definitions and exemplars of significant text segments and applying it to the collected data revealed several themes. For example, mothers, friends, teachers, the Internet, and social media are among the most common sources of information about menstrual hygiene and health. Yet, women reported that those sources of information often echoed stigmatized ideas about menstruation, eliciting feelings of shame and fear. That poor quality of information was instrumental to women’s abilities to detect and report abnormal menstrual bleeding. Women desire and need biologically accurate information about reproductive health, including menstruation and ovulation, fertility, and methods of birth control as treatments for abnormal menstrual bleeding. Unfortunately, menstrual education often leaves girls ill-equipped to identify and seek treatment for common gynecological conditions. Those findings may influence current menstrual education, incorporating biological information and actively dismissing common misconceptions about menstruation that influence stigma.
ContributorsSantora, Emily Katherine (Author) / Maienschein, Jane (Thesis advisor) / Ellison, Karin (Committee member) / Hurlbut, Ben (Committee member) / Arizona State University (Publisher)
Created2021