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- All Subjects: Chemistry
- Creators: Arizona State University
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
This study explored female identity formation, of Ethiopian women and women of Ethiopian heritage as they participate in a coffee (buna) ceremony ritual. The study is anchored in the theoretical framework of a sociocultural perspective which enabled an examination of culture as what individuals do and believe as they participate in mutually constituted activities. Participants in Ethiopia were asked to photograph their daily routine beginning from the time they awoke until they retired for the night. Thematic analysis of the photographs determined that all participants depicted participation in the Ethiopian coffee ceremony in their photo study. Utilizing the photographs which specifically depicted the ceremony, eight focus groups and one interview consisting of women who have migrated from Ethiopia to Arizona, responded to the typicality of the photographs, as well as what they liked or did not like about the photographs. Focus groups were digitally recorded then transcribed for analysis. A combination of coding, extrapolation of rich texts, and identifying themes and patterns were used to analyze transcripts of the focus groups and interview. The findings suggest that this context is rich with shared meanings pertaining to: material artifacts, gender socialization, creation of a space for free expression, social expectations for communal contributions, and a female rite of passage.
ContributorsPlatt, Jennifer Brinkerhoff, 1971- (Author) / Arzubiaga, Angela (Thesis advisor) / Nakagawa, Kathryn (Thesis advisor) / Warriner, Doris (Committee member) / Arizona State University (Publisher)
Created2011
Description
This dissertation examines associations between religious affiliation, religious community context and health of women and their children in Mozambique focusing on the following issues: (1) attending prenatal consultations and delivering children in a health facility; (2) women's symptoms of STDs; and (3) under-five mortality. Estimation of random intercept Poisson regression for the outcome about attending prenatal consultations demonstrated a favorable effect of affiliation to Catholic or Mainline Protestant and Apostolic religious groups. The concentration of Zionist churches in the community had a negative influence. Random intercept logistic regression was used to estimate the relationship between religion and institutional child delivery. Affiliation to Catholic or Mainline Protestant denominations as well as concentration of Catholic or Mainline Protestant churches in the community had some beneficial effect on giving birth in health clinics. The presence of Zionist churches in the community had some negative effect and that of other groups no significant influence. Random intercept logistic regression was also employed for investigating the influence of religion on women's symptoms of STDs. Belonging to the Catholic or Mainline Protestant church had some protective effect on reporting symptoms of STDs. There was no effect of religious context, except that the concentration of Other Pentecostal churches had a positive effect on reporting symptoms of SDTs. Event-history analysis was conducted for examining relationships between maternal religious affiliation with under-five mortality. Affiliation to Catholic or Mainline Protestant churches and to Apostolic denominations increased the odds of child survival, although, the influence of having a mother belonging to Catholic or Mainline Protestant churches lost statistical significance after accounting particularly for the average level of education in the community, for the period of 5 years preceding the survey date. Taken together, the results in this dissertation show some protective effect of religion that varies primarily by denominational group to which women are affiliated. They also indicate that religious community context may have some negative effect on health of women and children. The nature of the effect of religious community context varies with the type of outcome considered and the type of religious mixture in the community.
ContributorsCau, Boaventura Manuel (Author) / Agadjanian, Victor (Thesis advisor) / Hayford, Sarah (Committee member) / Yabiku, Scott (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
Description
Historians often characterize first ladies in the Progressive Era as representatives of the last vestiges of Victorian womanhood in an increasingly modern society. This dissertation argues that first ladies negotiated an image of themselves that fulfilled both traditional and modern notions of womanhood. In crafting these images, first ladies constructed images of their celebrity selves that were uniquely modern. Thus, images of first ladies in the Progressive Era show them as modest and feminine but also autonomous, intelligent, and capable. Using the historian Charles Ponce de Leon's research on modern human-interest journalism, I contend that first ladies in the Progressive Era worked with the modern press in a symbiotic relationship. This relationship allowed the press exclusive access to what was, ostensibly, the first lady's private, and therefore authentic, self. By purporting to reveal parts of their private lives in the press, first ladies showed themselves as down-to-earth despite their success and fulfilled by their domestic pursuits despite their compelling public lives. By offering the press exclusive access to their lives, first ladies secured the opportunity to shape specific images of themselves to appeal, as broadly as possible, to their husbands and parties' constituents and the American public. First ladies in the Progressive Era thus acted as political figures by using both public and private, or what historian Catherine Allgor terms, "unofficial spaces" to support and reflect their husbands and parties' political agendas. In examining representations of first ladies in popular magazines and newspapers from 1901 to 1921 in tandem with letters, memoirs, and other personal papers from these women, a clear pattern emerges. Despite personal differences, first ladies in the Progressive Era represented themselves according to a specific formula in the modern press. The images, constructed by first ladies in this time period, reflect shifts in economic, social, and political life in Progressive Era America, which called for women to be independent and intelligent yet still maintain their femininity and domesticity.
ContributorsHorohoe, Jill (Author) / Gullett, Gayle (Thesis advisor) / Longley, Rodney K (Committee member) / Warren-Findley, Jannelle (Committee member) / Arizona State University (Publisher)
Created2011
Description
This study examines the differences in demographic and life characteristics between transgender and female prostitutes in a prostitution diversion program and identifies specialized treatment and exiting strategies for transgender prostitutes. The purpose of this study was to develop a better understanding of the transgender experience in prostitution and to contribute to the descriptive literature. Participants were 465 individuals who were arrested for prostitution and attended a prostitution-focused diversion program. Differences found to be significant between transgender and female prostitutes included demographic characteristics, history of childhood sexual abuse, and experience of violence in prostitution. Implications for treatment, exiting strategies and future research are discussed.
ContributorsSchepel, Elizabeth (Author) / Roe-Sepowitz, Dominique (Thesis advisor) / Krysik, Judy (Committee member) / Androff, David (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
The AIDS epidemic has tremendously impacted the population of Mozambique. The rate of newly infected young women continues to grow disproportionately which is why consideration of health interventions specific to this population to combat the spread of the disease is critical. The Health Belief Model emphasizes the importance of self efficiency in the process of health related behavioral changes. Previous research has found that low levels of autonomy increase one's risk of contracting HIV/AIDS. This research uses data from a study conducted in 2006 in Mozambique to test whether higher levels of autonomy are associated with the practice of self protective behaviors related to the contraction of HIV/AIDS. Results suggest that some measures of autonomy such as education are positively associated with the practice of self protective behaviors. However, higher levels of decision making powers were negatively associated with the practice of self protective behaviors.
ContributorsWilliams, Kelli (Author) / Hayford, Sarah (Thesis advisor) / Agadjanian, Victor (Committee member) / Yabiku, Scott (Committee member) / Arizona State University (Publisher)
Created2011
Description
This thesis examines the 1994 Rwandan genocide with a specific emphasis on the rape of Tutsi women as a weapon of genocide. From the perspective of scholarship in trauma studies, an account of the conflict and colonialism leading up to the genocide is offered in order to demonstrate the historical making of the ground of collective trauma in Rwanda. Further, this thesis examines the discursive means of the perpetuation of collective trauma in the form of the Hutu demonization of Tutsi women. Shortcomings in the justice system emerging from the genocide are also discussed as a perpetuation of trauma. Finally, projects of justice and healing among Tutsi women are examined in an account of survival and resiliency. In conclusion, women that survived the genocide have navigated through societal and governmental systems to provide better lives for themselves, their families and the society.
ContributorsArmitage, Rebecca Lainé (Author) / Stancliff, Michael (Thesis advisor) / Casper, Monica (Committee member) / Simmons, William (Committee member) / Arizona State University (Publisher)
Created2011
Description
Despite the extensive research on the consequences of migration, little is known about the effects of seasonal migration on fertility, contraception and sexually transmitted diseases in the countries of former Soviet Union, that have undergone vast demographic changes in the last two decades. Using cross-sectional data from two surveys conducted in Armenia in 2005 and 2007, this dissertation is exploring the effects of seasonal migration on reproductive behavior and outcomes, as well as sexual health among women left-behind. The dissertation is constructed of three independent studies that combined draw the broad picture of the consequences of seasonal migration in this part of the world. The first study, "Seasonal migration and fertility in low-fertility areas of origin" looks at the effect of seasonal migration on yearly pregnancy rates, lifetime fertility, and fertility preferences among women and their husbands. The models are fitted using discrete-time logistic regression, and random-intercept logistic regression for negative binomial and binary outcomes, correspondingly. The findings show that seasonal migration in low-fertility settings does not further disrupt fertility levels in a short-, or long-run, contradicting to the findings from high-fertility settings. However, the study provides some evidence that seasonal migration is associated with increased fertility preferences among migrant men. The second study, "Seasonal migration and contraception among women left-behind", examines the associations between migration and modern contraceptive use, by looking at current contraceptive use and the history of abortions. A series of random-intercept logistic regression models reveal that women with migrant partners are significantly less likely to use modern contraceptives, than women married to non-migrants. They also have higher rates of abortions; however this effect is moderated by the socioeconomic status of the household. The third study, "Seasonal migration and risks of sexually transmitted diseases (STDs) among women left-behind", looks at the effects of seasonal migration on the diagnosed STDs in the last three years, and self reported STD-like symptoms in the last twelve months. The results of random-intercept logistic regression for negative binomial and binary outcomes provide strong evidence of increased STD risks among migrants' wives; however, this effect is also moderated by the household income.
ContributorsSevoyan, Arusyak (Author) / Agadjanian, Victor (Thesis advisor) / Haas, Steven (Committee member) / Yabiku, Scott (Committee member) / Arizona State University (Publisher)
Created2011