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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
As a result of the district program evaluation, a follow up on teacher perceptions of an online collaboration versus face to face collaboration approach was deemed necessary. The interviews were conducted with eight teachers from a suburban southwest K-8 public school district. After all teachers had participated in a 10 week program evaluation comparing online team teacher collaboration with face-to-face team teacher collaboration, the interview process began. One teacher from each grade level team was randomly selected to participate in the interview process. Analysis of the interview responses was inconclusive. Findings were confounded by the apparent lack of understanding of major concepts of Professional Learning Communities on the part of the participants. Assumptions about participant knowledge must be tested prior to investigations of the influence of either face to face or online format as delivery modes.
ContributorsTucker, Pamela K (Author) / McCoy, Kathleen (Thesis advisor) / Gehrke, Rebecca (Committee member) / Ham, Timothy (Committee member) / Arizona State University (Publisher)
Created2013
Description
Performance is a public speech act that can present the experience of difference and generate relations across lines of difference. In personal narrative performance, performers do not just tell stories, the stories they tell are strategic hailings that call attention to discourses that produce the conditions of their exclusion and form intimate relations in public. Personal narrative performance renders the private public. Performers take to the stage, the space of the public, to offer their stories, their bodies, and their relations to audiences for collective consideration. In turn, the act of performance generates further relations: among performers and audiences, and between performance and discourse. This study analyzes these two layers of relation in performance through looking at the ways neoliberalism and performance interanimate one another. Through looking at three sites of neoliberal relationality--same-sex marriage, family, and immigration and multiculturalism, it asks questions of how performers narrate and represent non-normative experiences within neoliberalism, the historical and cultural context through which they are living and narrating. In order to understand the cultural work, the resistive and relational potential, of the relations that occur in and through personal narrative performance, we also need to understand the political, cultural, and historical conditions under which narratives in performance are produced. My argument is that in and through performance intimacy is queered: it takes the private--the stuff of the personal presented as aesthetic communication--and renders that private very public. In public and through relations, performance can raise awareness and shift consciousness, reify orders of relation or generate alternate imaginaries. This is to say that a lot of different types of work are done in performance, and although performance is often seen as resistance, under the weight of neoliberalism, it is important to tend to what arguments performances are making and how in turn that shapes the relations that occur in the site of performance. Queer intimacy offers a way of engaging performance, an analytic that considers the text of performance as well as the relational context among performers and audiences, and turns back on larger cultural questions of belonging. The potential of performance, of the concept of queer intimacy, provides a lens to read performance, to tend to the conditions that give rise to and inform performance in the current historical moment. It brings together the critical impulse of intercultural communication and cultural studies with performance studies. From a critical cultural perspective, it tends to the structural in performance, and through performance emphasizes the lived experience as narrated and embodied as and through communication. Coupled with the impulses of queer theory, queer intimacy offers both resisting normativity and imagining beyond it. To consider queer intimacy in performance is not only to recognize that relations are made possible, but to tend closely to the belongings we are making.
ContributorsPérez, Kimberlee (Author) / Corey, Frederick C. (Thesis advisor) / Brouwer, Daniel C (Committee member) / Honegger, Gitta (Committee member) / Langellier, Kristin M (Committee member) / Arizona State University (Publisher)
Created2014
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
Description
Mathematical modeling of infectious diseases can help public health officials to make decisions related to the mitigation of epidemic outbreaks. However, over or under estimations of the morbidity of any infectious disease can be problematic. Therefore, public health officials can always make use of better models to study the potential implication of their decisions and strategies prior to their implementation. Previous work focuses on the mechanisms underlying the different epidemic waves observed in Mexico during the novel swine origin influenza H1N1 pandemic of 2009 and showed extensions of classical models in epidemiology by adding temporal variations in different parameters that are likely to change during the time course of an epidemic, such as, the influence of media, social distancing, school closures, and how vaccination policies may affect different aspects of the dynamics of an epidemic. This current work further examines the influence of different factors considering the randomness of events by adding stochastic processes to meta-population models. I present three different approaches to compare different stochastic methods by considering discrete and continuous time. For the continuous time stochastic modeling approach I consider the continuous-time Markov chain process using forward Kolmogorov equations, for the discrete time stochastic modeling I consider stochastic differential equations using Wiener's increment and Poisson point increments, and also I consider the discrete-time Markov chain process. These first two stochastic modeling approaches will be presented in a one city and two city epidemic models using, as a base, our deterministic model. The last one will be discussed briefly on a one city SIS and SIR-type model.
ContributorsCruz-Aponte, Maytee (Author) / Wirkus, Stephen A. (Thesis advisor) / Castillo-Chavez, Carlos (Thesis advisor) / Camacho, Erika T. (Committee member) / Kang, Yun (Committee member) / Arizona State University (Publisher)
Created2014
Description
Family caregivers are a quickly growing population in American society and are potentially vulnerable to a number of risks to well-being. High stress and little support can combine to cause difficulties in personal and professional relationships, physical health, and emotional health. Siblings are, however, a possible source of protection for the at-risk caregiver. This study examines the relational and health outcomes of gratitude exchange between caregivers and their siblings as they attend to the issue of caring for aging parents. Dyadic data was collected through an online survey and was analyzed using a series of Actor-Partner Interdependence Models. Intimacy and care conflict both closely relate to gratitude exchange, but the most significant variable influencing gratitude was role. Specifically, caregivers are neither experiencing nor expressing gratitude on the same level as their siblings. Expressed gratitude did not relate strongly or consistently to well-being variables, though it did relate to diminished negative affect. Implications for theory, the caregiver, the sibling, the elder, the practitioner, and the researcher are addressed in the discussion.
ContributorsAmaro, Lauren M (Author) / Miller, Katherine I. (Thesis advisor) / Alberts, Janet K. (Thesis advisor) / Updegraff, Kimberly (Committee member) / Arizona State University (Publisher)
Created2014
Description
The explicit role of soil organisms in shaping soil health, rates of pedogenesis, and resistance to erosion has only just recently begun to be explored in the last century. However, much of the research regarding soil biota and soil processes is centered on maintaining soil fertility (e.g., plant nutrient availability) and soil structure in mesic- and agro- ecosystems. Despite the empirical and theoretical strides made in soil ecology over the last few decades, questions regarding ecosystem function and soil processes remain, especially for arid areas. Arid areas have unique ecosystem biogeochemistry, decomposition processes, and soil microbial responses to moisture inputs that deviate from predictions derived using data generated in more mesic systems. For example, current paradigm predicts that soil microbes will respond positively to increasing moisture inputs in a water-limited environment, yet data collected in arid regions are not congruent with this hypothesis. The influence of abiotic factors on litter decomposition rates (e.g., photodegradation), litter quality and availability, soil moisture pulse size, and resulting feedbacks on detrital food web structure must be explicitly considered for advancing our understanding of arid land ecology. However, empirical data coupling arid belowground food webs and ecosystem processes are lacking. My dissertation explores the resource controls (soil organic matter and soil moisture) on food web network structure, size, and presence/absence of expected belowground trophic groups across a variety of sites in Arizona.
ContributorsWyant, Karl Arthur (Author) / Sabo, John L (Thesis advisor) / Elser, James J (Committee member) / Childers, Daniel L. (Committee member) / Hall, Sharon J (Committee member) / Stromberg, Juliet C. (Committee member) / Arizona State University (Publisher)
Created2014
Description
The purpose of this paper is to introduce a new method of dividing wireless communication (such as the 802.11a/b/g
and cellular UMTS MAC protocols) across multiple unreliable communication links (such as Ethernet). The purpose is to introduce the appropriate hardware, software, and system architecture required to provide the basis for a wireless system (using a 802.11a/b/g
and cellular protocols as a model) that can scale to support thousands of users simultaneously (say in a large office building, super chain store, etc.) or in a small, but very dense communication RF region. Elements of communication between a base station and a Mobile Station will be analyzed statistically to demonstrate higher throughput, fewer collisions and lower bit error rates (BER) with the given bandwidth defined by the 802.11n wireless specification (use of MIMO channels will be evaluated). A new network nodal paradigm will be presented. Alternative link layer communication techniques will be recommended and analyzed for the affect on mobile devices. The analysis will describe how the algorithms used by state machines implemented on Mobile Stations and Wi-Fi client devices will be influenced by new base station transmission behavior. New hardware design techniques that can be used to optimize this architecture as well as hardware design principles in regard to the minimal hardware functional blocks required to support such a system design will be described. Hardware design and verification simulation techniques to prove the hardware design will accommodate an acceptable level of performance to meet the strict timing as it relates to this new system architecture.
and cellular UMTS MAC protocols) across multiple unreliable communication links (such as Ethernet). The purpose is to introduce the appropriate hardware, software, and system architecture required to provide the basis for a wireless system (using a 802.11a/b/g
and cellular protocols as a model) that can scale to support thousands of users simultaneously (say in a large office building, super chain store, etc.) or in a small, but very dense communication RF region. Elements of communication between a base station and a Mobile Station will be analyzed statistically to demonstrate higher throughput, fewer collisions and lower bit error rates (BER) with the given bandwidth defined by the 802.11n wireless specification (use of MIMO channels will be evaluated). A new network nodal paradigm will be presented. Alternative link layer communication techniques will be recommended and analyzed for the affect on mobile devices. The analysis will describe how the algorithms used by state machines implemented on Mobile Stations and Wi-Fi client devices will be influenced by new base station transmission behavior. New hardware design techniques that can be used to optimize this architecture as well as hardware design principles in regard to the minimal hardware functional blocks required to support such a system design will be described. Hardware design and verification simulation techniques to prove the hardware design will accommodate an acceptable level of performance to meet the strict timing as it relates to this new system architecture.
ContributorsJames, Frank (Author) / Reisslein, Martin (Thesis advisor) / Ying, Lei (Committee member) / Zhang, Yanchao (Committee member) / Arizona State University (Publisher)
Created2014
Description
Foraging has complex effects on whole-organism homeostasis, and there is considerable evidence that foraging behavior is influenced by both environmental factors (e.g., food availability, predation risk) and the physiological condition of an organism. The optimization of foraging behavior to balance costs and benefits is termed state-dependent foraging (SDF) while behavior that seeks to protect assets of fitness is termed the asset protection principle (APP). A majority of studies examining SDF have focused on the role that energy balance has on the foraging of organisms with high metabolism and high energy demands ("high-energy systems" such as endotherms). In contrast, limited work has examined whether species with low energy use ("low-energy systems" such as vertebrate ectotherms) use an SDF strategy. Additionally, there is a paucity of evidence demonstrating how physiological and environmental factors other than energy balance influence foraging behavior (e.g. hydration state and free-standing water availability). Given these gaps in our understanding of SDF behavior and the APP, I examined the state-dependency and consequences of foraging in a low-energy system occupying a resource-limited environment - the Gila monster (Heloderma suspectum, Cope 1869). In contrast to what has been observed in a wide variety of taxa, I found that Gila monsters do not use a SDF strategy to manage their energy reserves and that Gila monsters do not defend their energetic assets. However, hydration state and free-standing water availability do affect foraging behavior of Gila monsters. Additionally, as Gila monsters become increasingly dehydrated, they reduce activity to defend hydration state. The SDF behavior of Gila monsters appears to be largely driven by the fact that Gila monsters must separately satisfy energy and water demands with food and free-standing water, respectively, in conjunction with the timescale within which Gila monsters balance their energy and water budgets (supra-annually versus annually, respectively). Given these findings, the impact of anticipated changes in temperature and rainfall patterns in the Sonoran Desert are most likely going to pose their greatest risks to Gila monsters through the direct and indirect effects on water balance.
ContributorsWright, Christian (Author) / Denardo, Dale F. (Thesis advisor) / Harrison, Jon (Committee member) / McGraw, Kevin (Committee member) / Sullivan, Brian (Committee member) / Wolf, Blair (Committee member) / Arizona State University (Publisher)
Created2014
Description
The &ldquoMormon; Colonies” in Chihuahua, northern Mexico, boast a sizable population of women originally from the United States who have immigrated to these small Mexican towns. This ethnographic study of the immigrant women in the area focuses on questions of citizenship and belonging, and bolsters the scholarship on U.S. American immigrants in Mexico. Using data from 15 unstructured interviews, the women&rsquos; experiences of migration provide a portrait of U.S. American immigrants in a Mexican religious community. Analysis of this data using grounded theory has revealed that these U.S. American women have created a third social space for themselves, to a large degree retaining their original culture, language, and political loyalty. Their stories contribute to the literature on transnational migration, providing an account of the way migrants of privilege interact with their society of settlement.
ContributorsNielsen, Vanessa (Author) / Mean, Lindsey (Thesis advisor) / Téllez, Michelle (Committee member) / Gruber, Diane (Committee member) / Arizona State University (Publisher)
Created2013