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Description
Newer communication technologies (CTs) will always vie with more mature technologies for the attention of time-constrained legislators. As continual advances in CT make new methods of communication available to legislators, it is important to understand how newly introduced CTs influence novel and changing legislator behaviors. The mixed-method research presented in this study provides deep insights into the relationships between legislators and the CTs they use. This study offers many contributions, among them: it effectively bridges a gap between existing Internet Enabled CT (IECT) behavioral studies on non-legislators by expanding them to include legislator behavior; it expands existing narrowly focused research into the use of CT by legislators by including both IECT and mature CTs such as face-to-face meetings and telephone; it provides a fresh perspective on the factors that make CTs important to legislators, and it uncovers legislator behaviors that are both useful, and potentially harmful, to the process of democracy in the United States. In addition, this study confirms and extends existing research in areas such as minority party constituent communication frequency, and extends the topic of legislator CT behavior into some unanticipated areas such as constituent selective behaviors and the use of text messaging during floor debates which effectively enable lobbyists and paid consultants to participate real-time in floor debates in the Arizona House and Senate.
ContributorsWest, Joe, 1959- (Author) / Corley, Elizabeth A (Thesis advisor) / Johnston, Erik W., 1977- (Committee member) / Svara, James H. (Committee member) / Arizona State University (Publisher)
Created2014
Description
In the countries of Eastern Europe, the recent history of the communist regimes creates a context rich in various and often times contradictory remembering practices. While normative discourses of memory enacted in official forms of memory such as museums, memorials, monuments, or commemorative rituals attempt to castigate the communism in definite terms, remembering practices enacted in everyday life are more ambiguous and more tolerant of various interpretations of the communist past. This study offers a case study of the ways in which people remember communism in everyday life in Romania. While various inquiries into Eastern Europe's and also Romania's official and intentional forms of memorializing communism abound, few works address remembering practices in their entanglements with everyday life. From a methodological point of view, this study integrates a grounded methodology approach with a rhetorical sensitivity to explore the discourses, objects, events, and practices of remembering communism in Bucharest, the capital city of Romania. In doing so, this inquiry attends not only to the aspects of the present that animate the remembering of communism, but also and more specifically to the set of practices by which the remembering process is performed. The qualitative analysis revealed a number of conceptual categories that clustered around three major themes that describe the entanglements of remembering activities with everyday life. Relating the present to the past, sustaining the past in the present, and pursuing the communist past constitute the ways in which people in Romania live their relationships with the communist past in a way that reveals the complex interplay between private and public forms of memory, but also between the political, social, and cultural aspects of the remembering process. These themes also facilitate a holistic understanding of the rhetorical environment of remembering communism in Romania.
ContributorsPaulesc, Marie-Louise (Author) / de la Garza, Sarah Amira (Thesis advisor) / Brouwer, Dan (Thesis advisor) / Gereboff, Joel (Committee member) / Arizona State University (Publisher)
Created2014
Description
Alzheimer's disease (AD) is the most common type of dementia, affecting one in nine people age 65 and older. One of the most important neuropathological characteristics of Alzheimer's disease is the aggregation and deposition of the protein beta-amyloid. Beta-amyloid is produced by proteolytic processing of the Amyloid Precursor Protein (APP). Production of beta-amyloid from APP is increased when cells are subject to stress since both APP and beta-secretase are upregulated by stress. An increased beta-amyloid level promotes aggregation of beta-amyloid into toxic species which cause an increase in reactive oxygen species (ROS) and a decrease in cell viability. Therefore reducing beta-amyloid generation is a promising method to control cell damage following stress. The goal of this thesis was to test the effect of inhibiting beta-amyloid production inside stressed AD cell model. Hydrogen peroxide was used as stressing agent. Two treatments were used to inhibit beta-amyloid production, including iBSec1, an scFv designed to block beta-secretase site of APP, and DIA10D, a bispecific tandem scFv engineered to cleave alpha-secretase site of APP and block beta-secretase site of APP. iBSec1 treatment was added extracellularly while DIA10D was stably expressed inside cell using PSECTAG vector. Increase in reactive oxygen species and decrease in cell viability were observed after addition of hydrogen peroxide to AD cell model. The increase in stress induced toxicity caused by addition of hydrogen peroxide was dramatically decreased by simultaneously treating the cells with iBSec1 or DIA10D to block the increase in beta-amyloid levels resulting from the upregulation of APP and beta-secretase.
ContributorsSuryadi, Vicky (Author) / Sierks, Michael (Thesis advisor) / Nielsen, David (Committee member) / Dai, Lenore (Committee member) / Arizona State University (Publisher)
Created2014
Description
The aim of this study is to test the feasibility of building a storytelling system for older adults to tell and share their life stories based on email. It is measured by the level of participation and people's acceptance of the system. The central goals were to empower people over 60 years old by providing a platform for them to share their wonderful life experience and perspectives on life and lead social services into the digital age by bridging traditional roundtable interaction and modern digital communication. A prototype was built to test the level of participation of the system and follow-up interviews were conducted in order to deeply understand people's acceptance. Content analysis was used to analyze the stories to ascertain what common themes were present. Key design considerations and key factors that affect the feasibility of storytelling system were discussed. This research expands on current research and implementation of Internet-based storytelling system and shed light on the future of combining storytelling with older adults' existing Internet knowledge. Key findings of this research are :(1) Frequency of reminiscence trigger and the number of active participants affect the level of participation collectively. Frequency is considered to be a key determinant. High frequency indicates high level of participation. (2) Categories of topics do not affect the level of participation significantly but serve as key attractions that enhance people's acceptance of the system. (3) Older adults highly accept and get involved in the new email storytelling system. This storytelling program helps them recall their memories and have a profound effect on their own introspection.
ContributorsLi, Yuanyi (Author) / Giard, Jacques R (Thesis advisor) / Margolis, Eric (Committee member) / Larkin, Kyle (Committee member) / Arizona State University (Publisher)
Created2014
Description
Flow measurement has always been one of the most critical processes in many industrial and clinical applications. The dynamic behavior of flow helps to define the state of a process. An industrial example would be that in an aircraft, where the rate of airflow passing the aircraft is used to determine the speed of the plane. A clinical example would be that the flow of a patient's breath which could help determine the state of the patient's lungs. This project is focused on the flow-meter that are used for airflow measurement in human lungs. In order to do these measurements, resistive-type flow-meters are commonly used in respiratory measurement systems. This method consists of passing the respiratory flow through a fluid resistive component, while measuring the resulting pressure drop, which is linearly related to volumetric flow rate. These types of flow-meters typically have a low frequency response but are adequate for most applications, including spirometry and respiration monitoring. In the case of lung parameter estimation methods, such as the Quick Obstruction Method, it becomes important to have a higher frequency response in the flow-meter so that the high frequency components in the flow are measurable. The following three types of flow-meters were: a. Capillary type b. Screen Pneumotach type c. Square Edge orifice type To measure the frequency response, a sinusoidal flow is generated with a small speaker and passed through the flow-meter that is connected to a large, rigid container. True flow is proportional to the derivative of the pressure inside the container. True flow is then compared with the measured flow, which is proportional to the pressure drop across the flow-meter. In order to do the characterization, two LabVIEW data acquisition programs have been developed, one for transducer calibration, and another one that records flow and pressure data for frequency response testing of the flow-meter. In addition, a model that explains the behavior exhibited by the flow-meter has been proposed and simulated. This model contains a fluid resistor and inductor in series. The final step in this project was to approximate the frequency response data to the developed model expressed as a transfer function.
ContributorsHu, Jianchen (Author) / Macia, Narciso (Thesis advisor) / Pollat, Scott (Committee member) / Rogers, Bradley (Committee member) / Arizona State University (Publisher)
Created2013
Description
A noninvasive optical method is developed to monitor rapid changes in blood glucose levels in diabetic patients. The system depends on an optical cell built with a LED that emits light of wavelength 535nm that is a peak absorbance of hemoglobin. As the glucose concentration in the blood decreases, its osmolarity also decreases and the RBCs swell and decrease the path length absorption coefficient. Decreasing absorption coefficient increases the transmission of light through the whole blood. The system was tested with a constructed optical cell that held whole blood in a capillary tube. As expected the light transmitted to the photodiode increases with decreasing glucose concentration. The average response time of the system was between 30-40 seconds. The changes in size of the RBC cells in response to glucose concentration changes were confirmed using a cell counter and also visually under microscope. This method does not allow measuring the glucose concentration with an absolute concentration calibration. It is directed towards development of a device to monitor the changes in glucose concentration as an aid to diabetic management. This method might be improvised for precision and resolution and be developed as a ring or an earring that patients can wear.
ContributorsRajan, Shiny Amala Priya (Author) / Towe, Bruce (Thesis advisor) / Muthuswamy, Jitendran (Committee member) / LaBelle, Jeffrey (Committee member) / Arizona State University (Publisher)
Created2013
Description
The economic crisis in 2008 triggered a global financial shockwave that left many wondering about the origins of the crisis. Similarly, in the early twentieth century, Wall Street faced catastrophic losses that set the stage for the Great Depression, which resulted in a decade of economic depression, leaving millions of people out of work. Using discourse analysis to understand how economic crisis is framed through the mainstream press, this research project analyzed the stock market crash of 1929-1932 and the mortgage-backed financial crisis of 2007-2009 through the lens of two mainstream publications, The New York Times and The Wall Street Journal. Comparative analysis focused on explanations for the causes of the crises, attributions of blame, culprits, and proposed solutions emerging in news coverage of the 1929 panic and the 2007-2009 financial crises. Mainstream media accounts of the 2007-2009 crisis are then compared with `alternative media' accounts of crisis causes, culprits, and solutions. These comparative analyses are contextualized historically within economic paradigms of thought, beginning with the classical economists led by Adam Smith and transitioning to the Chicago School.
ContributorsPrice, Eun (Author) / Nadesan, Majia (Thesis advisor) / Gruber, Diane (Committee member) / Ramsey, Ramsey E (Committee member) / Arizona State University (Publisher)
Created2013
Description
Coronary heart disease (CHD) is the most prevalent cause of death worldwide. Atherosclerosis which is the condition of plaque buildup on the inside of the coronary artery wall is the main cause of CHD. Rupture of unstable atherosclerotic coronary plaque is known to be the cause of acute coronary syndrome. The composition of plaque is important for detection of plaque vulnerability. Due to prognostic importance of early stage identification, non-invasive assessment of plaque characterization is necessary. Computed tomography (CT) has emerged as a non-invasive alternative to coronary angiography. Recently, dual energy CT (DECT) coronary angiography has been performed clinically. DECT scanners use two different X-ray energies in order to determine the energy dependency of tissue attenuation values for each voxel. They generate virtual monochromatic energy images, as well as material basis pair images. The characterization of plaque components by DECT is still an active research topic since overlap between the CT attenuations measured in plaque components and contrast material shows that the single mean density might not be an appropriate measure for characterization. This dissertation proposes feature extraction, feature selection and learning strategies for supervised characterization of coronary atherosclerotic plaques. In my first study, I proposed an approach for calcium quantification in contrast-enhanced examinations of the coronary arteries, potentially eliminating the need for an extra non-contrast X-ray acquisition. The ambiguity of separation of calcium from contrast material was solved by using virtual non-contrast images. Additional attenuation data provided by DECT provides valuable information for separation of lipid from fibrous plaque since the change of their attenuation as the energy level changes is different. My second study proposed these as the input to supervised learners for a more precise classification of lipid and fibrous plaques. My last study aimed at automatic segmentation of coronary arteries characterizing plaque components and lumen on contrast enhanced monochromatic X-ray images. This required extraction of features from regions of interests. This study proposed feature extraction strategies and selection of important ones. The results show that supervised learning on the proposed features provides promising results for automatic characterization of coronary atherosclerotic plaques by DECT.
ContributorsYamak, Didem (Author) / Akay, Metin (Thesis advisor) / Muthuswamy, Jit (Committee member) / Akay, Yasemin (Committee member) / Pavlicek, William (Committee member) / Vernon, Brent (Committee member) / Arizona State University (Publisher)
Created2013
Description
Controlled release formulations for local, in vivo drug delivery are of growing interest to device manufacturers, research scientists, and clinicians; however, most research characterizing controlled release formulations occurs in vitro because the spatial and temporal distribution of drug delivery is difficult to measure in vivo. In this work, in vivo magnetic resonance imaging (MRI) of local drug delivery is performed to visualize and quantify the time resolved distribution of MRI contrast agents. I find it is possible to visualize contrast agent distributions in near real time from local delivery vehicles using MRI. Three dimensional T1 maps are processed to produce in vivo concentration maps of contrast agent for individual animal models. The method for obtaining concentration maps is analyzed to estimate errors introduced at various steps in the process. The method is used to evaluate different controlled release vehicles, vehicle placement, and type of surgical wound in rabbits as a model for antimicrobial delivery to orthopaedic infection sites. I are able to see differences between all these factors; however, all images show that contrast agent remains fairly local to the wound site and do not distribute to tissues far from the implant in therapeutic concentrations. I also produce a mathematical model that investigates important mechanisms in the transport of antimicrobials in a wound environment. It is determined from both the images and the mathematical model that antimicrobial distribution in an orthopaedic wounds is dependent on both diffusive and convective mechanisms. Furthermore, I began development of MRI visible therapeutic agents to examine active drug distributions. I hypothesize that this work can be developed into a non-invasive, patient specific, clinical tool to evaluate the success of interventional procedures using local drug delivery vehicles.
ContributorsGiers, Morgan (Author) / Caplan, Michael R (Thesis advisor) / Massia, Stephen P (Committee member) / Frakes, David (Committee member) / McLaren, Alex C. (Committee member) / Vernon, Brent L (Committee member) / Arizona State University (Publisher)
Created2013
Description
Cell-cell interactions in a microenvironment under stress conditions play a critical role in pathogenesis and pre-malignant progression. Hypoxia is a central factor in carcinogenesis, which induces selective pressure in this process. Understanding the role of intercellular communications and cellular adaptation to hypoxia can help discover new cancer biosignatures and more effective diagnostic and therapeutic strategies. This dissertation presents a study on transcriptomic and metabolic profiling of pre-malignant progression of Barrett's esophagus. It encompasses two methodology developments and experimental findings of two related studies. To integrate phenotype and genotype measurements, a minimally invasive method was developed for selectively retrieving single adherent cells from cell cultures. Selected single cells can be harvested by a combination of mechanical force and biochemical treatment after phenotype measurements and used for end-point assays. Furthermore, a method was developed for analyzing expression levels of ten genes in individual mammalian cells with high sensitivity and reproducibility without the need of pre-amplifying cDNA. It is inexpensive and compatible with most of commercially available RT-qPCR systems, which warrants a wide applicability of the method to gene expression analysis in single cells. In the first study, the effect of intercellular interactions was investigated between normal esophageal epithelial and dysplastic Barrett's esophagus cells on gene expression levels and cellular functions. As a result, gene expression levels in dysplastic cells were found to be affected to a significantly larger extent than in the normal esophageal epithelial cells. These differentially expressed genes are enriched in cellular movement, TGFβ and EGF signaling networks. Heterotypic interactions between normal and dysplastic cells can change cellular motility and inhibit proliferation in both normal and dysplastic cells. In the second study, alterations in gene transcription levels and metabolic phenotypes between hypoxia-adapted cells and age-matched normoxic controls representing four different stages of pre-malignant progression in Barrett's esophagus were investigated. Through differential gene expression analysis and mitochondrial membrane potential measurements, evidence of clonal evolution induced by hypoxia selection pressure in metaplastic and high-grade dysplastic cells was found. These discoveries on cell-cell interactions and hypoxia adaptations provide a deeper insight into the dynamic evolutionary process in pre-malignant progression of Barrett's esophagus.
ContributorsZeng, Jia (Author) / Meldrum, Deirdre R (Thesis advisor) / Kelbauskas, Laimonas (Committee member) / Barrett, Michael T (Committee member) / Bussey, Kimberly J (Committee member) / Zhang, Weiwen (Committee member) / Arizona State University (Publisher)
Created2014