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- All Subjects: Chemistry
- All Subjects: Communication
- Genre: Doctoral Dissertation
- Creators: Arizona State University
- Creators: Hayes, Mark A.
Description
Bioparticles comprise a diverse amount of materials ubiquitously present in nature. From proteins to aerosolized biological debris, bioparticles have important roles spanning from regulating cellular functions to possibly influencing global climate. Understanding their structures, functions, and properties provides the necessary tools to expand our fundamental knowledge of biological systems and exploit them for useful applications. In order to contribute to this efforts, the work presented in this dissertation focuses on the study of electrokinetic properties of liposomes and novel applications of bioaerosol analysis. Using immobilized lipid vesicles under the influence of modest (less than 100 V/cm) electric fields, a novel strategy for bionanotubule fabrication with superior throughput and simplicity was developed. Fluorescence and bright field microscopy was used to describe the formation of these bilayer-bound cylindrical structures, which have been previously identified in nature (playing crucial roles in intercellular communication) and made synthetically by direct mechanical manipulation of membranes. In the biological context, the results of this work suggest that mechanical electrostatic interaction may play a role in the shape and function of individual biological membranes and networks of membrane-bound structures. A second project involving liposomes focused on membrane potential measurements in vesicles containing trans-membrane pH gradients. These types of gradients consist of differential charge states in the lipid bilayer leaflets, which have been shown to greatly influence the efficacy of drug targeting and the treatment of diseases such as cancer. Here, these systems are qualitatively and quantitatively assessed by using voltage-sensitive membrane dyes and fluorescence spectroscopy. Bioaerosol studies involved exploring the feasibility of a fingerprinting technology based on current understanding of cellular debris in aerosols and arguments regarding sampling, sensitivity, separations and detection schemes of these debris. Aerosolized particles of cellular material and proteins emitted by humans, animals and plants can be considered information-rich packets that carry biochemical information specific to the living organisms present in the collection settings. These materials could potentially be exploited for identification purposes. Preliminary studies evaluated protein concentration trends in both indoor and outdoor locations. Results indicated that concentrations correlate to certain conditions of the collection environment (e.g. extent of human presence), supporting the idea that bioaerosol fingerprinting is possible.
ContributorsCastillo Gutiérrez, Josemar Andreina (Author) / Hayes, Mark A. (Thesis advisor) / Herckes, Pierre (Committee member) / Ghrilanda, Giovanna (Committee member) / Arizona State University (Publisher)
Created2011
Description
The United States is facing an emerging principal shortage. This study examines an intervention to deliver professional development for assistant principals on their way to becoming principals. The intervention intended to boost their sense of efficacy as if they were principals while creating a supportive community of professionals for ongoing professional learning. The community was designed much like a professional learning community (PLC) with the intent of developing into a community of practice (CoP). The participants were all elementary school assistant principals in a Title I district in a large metropolitan area. The researcher interviewed an expert set of school administrators consisting of superintendents and consultants (and others who have knowledge of what a good principal ought to be) about what characteristics and skills were left wanting in principal applicants. The data from these interviews provided the discussion topics for the intervention. The assistant principals met regularly over the course of a semester and discussed the topics provided by the expert set of school administrators. Participant interaction within the sessions followed conversation protocols. The researcher was also a participant in the group and served as the coordinator. Each session was recorded and transcribed. The researcher used a mixed methods approach to analyze the intervention. Participants were surveyed to measure their efficacy before and after the intervention. The session transcripts were analyzed using open and axial coding. Data showed no statistically significant change in the participants' sense of efficacy. Data also showed the participants became a coalescing community of practice.
ContributorsRichman, Bryan (Author) / Puckett, Kathleen (Thesis advisor) / Smith, Jeffery (Committee member) / Foulger, Teresa (Committee member) / Arizona State University (Publisher)
Created2011
Description
This dissertation explores the rhetorical significance of persecution claims produced by demonstrably powerful publics in contemporary American culture. This ideological criticism is driven by several related research questions. First, how do members of apparently powerful groups (men, whites, and Christians) come to see themselves as somehow unjustly marginalized, persecuted, or powerless? Second, how are these discourses related to the public sphere and counterpublicity? I argue that, despite startling similarities, these texts studied here are best understood not as counterpublicity but as a strategy of containment available to hegemonic publics. Because these rhetorics of persecution often seek to forestall movements toward pluralism and restorative justice, the analysis forwarded in this dissertation offers important contributions to ongoing theoretical discussions in the fields of public sphere theory and critical cultural theory and practical advice for progressive political activism and critical pedagogy.
ContributorsDuerringer, Christopher (Author) / Brouwer, Daniel (Thesis advisor) / Carlson, Cheree (Committee member) / McDonald, Kelly (Committee member) / Arizona State University (Publisher)
Created2011
Description
Applications of non-traditional stable isotope variations are moving beyond geosciences to biomedicine, made possible by advances in multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) technology. Mass-dependent isotope variation can provide information about the sources of elements and the chemical reactions that they undergo. Iron and calcium isotope systematics in biomedicine are relatively unexplored but have great potential scientific interest due to their essential nature in metabolism. Iron, a crucial element in biology, fractionates during biochemically relevant reactions. To test the extent of this fractionation in an important reaction process, equilibrium iron isotope fractionation during organic ligand exchange was determined. The results show that iron fractionates during organic ligand exchange, and that isotope enrichment increases as a function of the difference in binding constants between ligands. Additionally, to create a mass balance model for iron in a whole organism, iron isotope compositions in a whole mouse and in individual mouse organs were measured. The results indicate that fractionation occurs during transfer between individual organs, and that the whole organism was isotopically light compared with food. These two experiments advance our ability to interpret stable iron isotopes in biomedicine. Previous research demonstrated that calcium isotope variations in urine can be used as an indicator of changes in net bone mineral balance. In order to measure calcium isotopes by MC-ICP-MS, a chemical purification method was developed to quantitatively separate calcium from other elements in a biological matrix. Subsequently, this method was used to evaluate if calcium isotopes respond when organisms are subjected to conditions known to induce bone loss: 1) Rhesus monkeys were given an estrogen-suppressing drug; 2) Human patients underwent extended bed rest. In both studies, there were rapid, detectable changes in calcium isotope compositions from baseline - verifying that calcium isotopes can be used to rapidly detect changes in bone mineral balance. By characterizing iron isotope fractionation in biologically relevant processes and by demonstrating that calcium isotopes vary rapidly in response to bone loss, this thesis represents an important step in utilizing these isotope systems as a diagnostic and mechanistic tool to study the metabolism of these elements in vivo.
ContributorsMorgan, Jennifer Lynn Louden (Author) / Anbar, Ariel D. (Thesis advisor) / Wasylenki, Laura E. (Committee member) / Jones, Anne K. (Committee member) / Shock, Everett (Committee member) / Arizona State University (Publisher)
Created2011
Deviant bodies resisting online: examining the intersecting realities of women of color in Xbox Live
Description
Employing qualitative methods and drawing from an intersectional framework which focuses on the multiple identities we all embody, this dissertation focuses on oppressions and resistance strategies employed by women of color in Xbox live, an online gaming community. Ethnographic observations and narrative interviewing reveal that women of color, as deviants within the space, face intersecting oppressions in gaming as in life outside the gaming world. They are linguistically profiled within the space based off of how they sound. They have responded with various strategies to combat the discrimination they experience. Some segregate themselves from the larger gaming population and many refuse to purchase games that depict women in a hyper-sexualized manner or that present people of color stereotypically. For others, the solution is to "sit-in" on games and disrupt game flow by 'player-killing' or engage in other 'griefing' activities. I analyze this behavior in the context of Black feminist consciousness and resistance and uncover that these methods are similar to women who employ resistance strategies for survival within the real world.
ContributorsGray, Kishonna (Author) / Anderson, Lisa M. (Thesis advisor) / Cheong, Pauline (Committee member) / Lim, Merlyna (Committee member) / Arizona State University (Publisher)
Created2011
Description
The electrode-electrolyte interface in electrochemical environments involves the understanding of complex processes relevant for all electrochemical applications. Some of these processes include electronic structure, charge storage, charge transfer, solvent dynamics and structure and surface adsorption. In order to engineer electrochemical systems, no matter the function, requires fundamental intuition of all the processes at the interface. The following work presents different systems in which the electrode-electrolyte interface is highly important. The first is a charge storage electrode utilizing percolation theory to develop an electrode architecture producing high capacities. This is followed by Zn deposition in an ionic liquid in which the deposition morphology is highly dependant on the charge transfer and surface adsorption at the interface. Electrode Architecture: A three-dimensional manganese oxide supercapacitor electrode architecture is synthesized by leveraging percolation theory to develop a hierarchically designed tri-continuous percolated network. The three percolated phases include a faradaically-active material, electrically conductive material and pore-former templated void space. The micropores create pathways for ionic conductivity, while the nanoscale electrically conducting phase provides both bulk conductivity and local electron transfer with the electrochemically active phase. Zn Electrodeposition: Zn redox in air and water stable N-ethyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, [C2nmm][NTf2] is presented. Under various conditions, characterization of overpotential, kinetics and diffusion of Zn species and morphological evolution as a function of overpotential and Zn concentration are analyzed. The surface stress evolution during Zn deposition is examined where grain size and texturing play significant rolls in compressive stress generation. Morphological repeatability in the ILs led to a novel study of purity in ionic liquids where it is found that surface adsorption of residual amine and chloride from the organic synthesis affect growth characteristics. The drivers of this work are to understand the processes occurring at the electrode-electrolyte interface and with that knowledge, engineer systems yielding optimal performance. With this in mind, the design of a bulk supercapacitor electrode architecture with excellent composite specific capacitances, as well as develop conditions producing ideal Zn deposition morphologies was completed.
ContributorsEngstrom, Erika (Author) / Friesen, Cody (Thesis advisor) / Buttry, Daniel (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created2011
Description
Dangerous drinking on college campuses is a significant public health issue. Over the last decade, the National Institute on Alcohol Abuse and Alcoholism and the U.S. Department of Health and Human Services have called on universities, community leaders, policymakers, parents and students to work together to develop effective, research based alcohol prevention and/or intervention programs. Despite such calls, parent-based prevention programs are relatively rare on college campuses, and there is a paucity of research on the ways in which parents influence their emerging adult children's drinking behaviors. The present project is designed to help address this need. Grounded in social cognitive theory, this exploratory study focuses on alcohol communication and poses numerous questions regarding the alcohol messages exchanged between college students and their parents, as well as how such messages associate with college students' dangerous drinking. Undergraduate students ages 18 to 25 who were enrolled in communication classes were recruited for the study and asked to recruit a parent. The sample included 198 students and 188 parents, all of whom completed an online survey. Results indicated the majority of college students have had alcohol conversations with a parent since the student graduated from high school. Parents viewed such conversations as significantly more open, direct, and ongoing than did students; though both generally agreed on the content of their alcohol communication, reporting an emphasis on the negative aspects of drinking, particularly the dangers of drinking and driving and the academic consequences of too much partying. Frequent discussions of drinking risks had significant, positive associations with students' dangerous drinking, whereas parents' reports of discussing rules about alcohol had a significant negative association with students' alcohol consumption. There were strong significant associations between the types alcohol topics discussed and students' perception that their parents approved of their drinking, as well as parents' actual approval. Perceived approval had a significant, positive association with students' dangerous drinking; however, actual parental approval was not a significant predictor of students' drinking outcomes. Parents' alcohol consumption had a significant positive association with students' alcohol consumption. Implications for parents, public health practitioners, and future research are discussed.
ContributorsMenegatos, Lisa Marie (Author) / Floyd, Kory (Thesis advisor) / Lederman, Linda C. (Thesis advisor) / Valiente, Carlos (Committee member) / Arizona State University (Publisher)
Created2011
Description
As digital technology promises immediacy and interactivity in communication, sight and sound in motion graphics has expanded the range of design possibilities in advertising, social networking, and telecommunication beyond the visual realm. The experience of seeing has been greatly enriched by sound as visual solutions become dynamic and multi-dimensional. The ability to record and transfer sight and sound with new media has granted the designer more control in manipulating a viewer's experience of time and space. This control allows time-based form to become the foundation that establishes many interactive, multisensory and interdisciplinary applications. Is conventional design theory for print media adequate to effectively approach time-based form? If not, what is the core element that is required to balance the static and dynamic aspects of time in new media? Should time-related theories and methodologies from other disciplines be adopted into our design principles? If so, how would this knowledge be integrated? How can this experience in time be effectively transferred to paper? Unless the role of the time dimension in sight is operationally deconstructed and retained with sound, it is very challenging to control the design in this fugitive form. Time activation refers to how time and the perception of time can be manipulated for design and communication purposes. Sound, as a shortcut to the active time design element, not only encapsulates the structure of its "invisible" time-based form, but also makes changes in time conspicuously measurable and comparable. Two experiments reflect the influence of sound on imagery, a slideshow and video, as well as how the dynamics in time are represented across all design media. A cyclical time-based model is established to reconnect the conventional design principles learned in print media with time-based media. This knowledge helps expand static images to motion and encapsulate motion in stasis. The findings provide creative methods for approaching visualization, interactivity, and design education.
ContributorsCheung, Hoi Yan Patrick (Author) / Giard, Jacques (Thesis advisor) / Sanft, Alfred C (Committee member) / Aisling, Kelliher (Committee member) / Arizona State University (Publisher)
Created2011
Description
The division of domestic labor has far-reaching implications for "private" life (e.g. relational satisfaction and conflict) and for "public" paid labor (e.g. time and dedication in the workplace and career advancement). Although several theories have been developed and tested, they do not sufficiently explain the consistent findings that women in mixed sex households perform a majority of the domestic labor. Without understanding the causes for differences in task performance, past research encouraging communicative solutions to ameliorate conflict was ineffective in changing task allocation and performance. Therefore, it is necessary to understand theoretical explanations that drive domestic labor behavior to develop effective solutions. The recent integrative theory of the division of domestic labor attempts to explain how individuals interact with household partners to allocate domestic tasks. Recognizing the complexity of the division of domestic labor, the integrative theory considers individual, dyadic, and societal factors that influence task allocation. Because clear differences in task performance have been found in mixed sex households, this study separates sex and gender as distinct variables by considering same-sex roommate relationships, essentially removing sex differences from the living arrangement. Furthermore, this study considers individual threshold levels as described by the integrative theory in order to test the theoretical underpinnings. Specifically, this study is designed to investigate the relationships between individual cleanliness threshold levels and gender, sex, perceptions of satisfaction, equity, and frequency of conflict in same-sex roommate relationships. Results indicate support of the integrative theory of the division of domestic labor. Regarding gender differences, partial support for the theory appeared in that feminine individuals have lower threshold levels than masculine individuals. Regarding sex differences, women possess lower individual threshold levels (i.e. more bothered when a task is undone) compared to men, which likely accounts for why existing research indicates that women spend more time performing domestic tasks. What is more, individuals with higher threshold levels report greater relational satisfaction. Further, individuals whose threshold levels differ from their living partner report lower relational satisfaction and greater conflict frequency. Finally, in terms of equity, both overbenefited and underbenefited individuals experience more conflict than those who feel their relationship is equitable. These results provide theoretical support for the integrative theory of the division of labor. Furthermore, the development and testing of a threshold measure scale can be used practically for future research and for better roommate pairings by universities. In addition, communication scholars, family practitioners and counselors, and universities can apply these theoretically grounded research findings to develop and test strategies to reduce conflict and increase relational satisfaction among roommates and couples.
ContributorsRiforgiate, Sarah (Author) / Alberts, Jess K. (Thesis advisor) / Mongeau, Paul (Thesis advisor) / Roberto, Anthony (Committee member) / Romero, Mary (Committee member) / Arizona State University (Publisher)
Created2011
Description
A new challenge on the horizon is to utilize the large amounts of protein found in the atmosphere to identify different organisms from which the protein originated. Included here is work investigating the presence of identifiable patterns of different proteins collected from the air and biological samples for the purposes of remote identification. Protein patterns were generated using high performance liquid chromatography (HPLC). Patterns created could identify high-traffic and low-traffic indoor spaces. Samples were collected from the air using air pumps to draw air through a filter paper trapping particulates, including large amounts of shed protein matter. In complimentary research aerosolized biological samples were collected from various ecosystems throughout Ecuador to explore the relationship between environmental setting and aerosolized protein concentrations. In order to further enhance protein separation and produce more detailed patterns for the identification of individual organisms of interest; a novel separation device was constructed and characterized. The separation device incorporates a longitudinal gradient as well as insulating dielectrophoretic features within a single channel. This design allows for the production of stronger local field gradients along a global gradient allowing particles to enter, initially transported through the channel by electrophoresis and electroosmosis, and to be isolated according to their characteristic physical properties, including charge, polarizability, deformability, surface charge mobility, dielectric features, and local capacitance. Thus, different types of particles are simultaneously separated at different points along the channel distance given small variations of properties. The device has shown the ability to separate analytes over a large dynamic range of size, from 20 nm to 1 μm, roughly the size of proteins to the size of cells. In the study of different sized sulfate capped polystyrene particles were shown to be selectively captured as well as concentrating particles from 103 to 106 times. Qualitative capture and manipulation of β-amyloid fibrils were also shown. The results demonstrate the selective focusing ability of the technique; and it may form the foundation for a versatile tool for separating complex mixtures. Combined this work shows promise for future identification of individual organisms from aerosolized protein as well as for applications in biomedical research.
ContributorsStaton, Sarah J. R (Author) / Hayes, Mark A. (Committee member) / Anbar, Ariel D (Committee member) / Shock, Everett (Committee member) / Williams, Peter (Committee member) / Arizona State University (Publisher)
Created2011