Matching Items (43,913)
Description
Health-related quality of life (HR-QOL) is a significant treatment outcome for persons with end-stage renal disease (ESRD); however, little is known about the HR-QOL of Mexican patients with ESRD. This pilot study describes relationships between demographics, sleep disorders, spirituality, mood, folk practices and dialysis modality on the HR-QOL of patients with ESRD residing in Guanajuato, Mexico. Mexican patients receiving continuous ambulatory peritoneal dialysis (CAPD), automated peritoneal dialysis (APD) and hemodialysis (HD) provided information on demographics, clinical health data including body mass index (BMI), and folk health practices. Measures included the Short Form (SF)-36 HR-QOL survey, Sleep Habits Questionnaire, Latin Spirituality Perspective Scale and Hospital Anxiety and Depression Scale. Data were analyzed using SAS software (V9.1). Signifi¬cance level for this pilot study was set at p<0.10. The Quality-Adjusted Life Year method was utilized to examine cost effectiveness for each dialysis modality. Demographics and clinical data showed participants (N=121) to be 59 (SD=13) years, predominantly men (55.4%), married (66.9%), Catholic (92.6%), and not currently working (78.3%). The majority were diabetic (72%) and slightly overweight (BMI M=26.1; SD=5.1). The CAPD group (n=39) demonstrated significantly lower HR-QOL scores compared to the APD (n=42) and HD (n=40) groups. Patients on HD reported higher rates and greater numbers of sleep disorders, including insomnia symptoms, non-restorative and insufficient sleep, and daytime somnolence compared to patients on CAPD and APD. Patients on CAPD reported more anxiety and depression compared to patients on HD and APD. Overall linear regression for HR-QOL found dialysis type, sleep disorders and income to be significant predictors and the model accounted for 31% of the variance. Cost analysis indicated APD as the preferred treatment because it is less costly and results in the best HR-QOL compared to the other treatment modalities. Findings provide the first SF-36 norms for Mexicans with ESRD. Sleep disorders and dialysis type greatly impinge on the HR-QOL of these patients, particularly their mental health. APD was identified as the preferred treatment based on low cost and improved HR-QOL. Results can inform clinical care and health policy for Mexican patients with ESRD.
ContributorsReynaga-Ornelas, Luxana (Author) / Baldwin, Carol M. (Thesis advisor) / Quan, Stuart F (Committee member) / Arcoleo, Kimberly (Committee member) / Arizona State University (Publisher)
Created2011
Description
This thesis explores the implications that the outcome of a certain U.S. lawsuit involving antiquities could have on practices and programs in the United States, related to cultural heritage and history. This paper examines the Rubin et al case, which sought to attach a collection of ancient Persian artifacts (known as The Persepolis Tablets) as a source of legal compensation. Presented as a case study, and using primary and secondary research sources, this paper analyzes the Rubin et al lawsuit and the factors that led to its initiation, and seeks to determine how and why adverse consequences could result from its final ruling. This thesis demonstrates that the final decision in the lawsuit could leave a negative impact on a number of practices related to cultural heritage in the United States, especially with regards to cultural and academic institutions such as museums and universities.
ContributorsAhouraiyan, Taraneh (Author) / Warren-Findley, Jannelle (Thesis advisor) / Warrren-Findley, Jannelle (Committee member) / Thompson, Victoria (Committee member) / Smith, Louis (Committee member) / Arizona State University (Publisher)
Created2011
Description
Thin film transistors (TFTs) are being used in a wide variety of applications such as image sensors, radiation detectors, as well as for use in liquid crystal displays. However, there is a conspicuous absence of interface electronics for bridging the gap between the flexible sensors and digitized displays. Hence is the need to build the same. In this thesis, the feasibility of building mixed analog circuits in TFTs are explored and demonstrated. A flexible CMOS op-amp is demonstrated using a-Si:H and pentacene TFTs. The achieved performance is ¡Ö 50 dB of DC open loop gain with unity gain frequency (UGF) of 7 kHz. The op-amp is built on the popular 2 stage topology with the 2nd stage being cascoded to provide sufficient gain. A novel biasing circuit was successfully developed modifying the gm biasing circuit to retard the performance degradation as the TFTs aged. A switched capacitor 7 bit DAC was developed in only nMOS topology using a-Si:H TFTs, based on charge sharing concept. The DAC achieved a maximum differential non-linearity (DNL) of 0.6 least significant bit (LSB), while the maximum integral non-linearity (INL) was 1 LSB. TFTs were used as switches in this architecture; as a result the performance was quite unchanged even as the TFTs degraded. A 5 bit fully flash ADC was also designed using all nMOS a-Si:H TFTs. Gray coding was implemented at the output to avoid errors due to comparator meta-stability. Finally a 5 bit current steering DAC was also built using all nMOS a-Si:H TFTs. However, due to process variation, the DNL was increased to 1.2 while the INL was about 1.8 LSB. Measurements were made on the external stress effects on zinc indium oxide (ZIO) TFTs. Electrically induced stresses were studied applying DC bias on the gate and drain. These stresses shifted the device characteristics like threshold voltage and mobility. The TFTs were then mechanically stressed by stretching them across cylindrical structures of various radii. Both the subthreshold swing and mobility underwent significant changes when the stress was tensile while the change was minor under compressive stress, applied parallel to channel length.
ContributorsDey, Aritra (Author) / Allee, David R. (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Garrity, Douglas A (Committee member) / Song, Hongjiang (Committee member) / Clark, Lawrence T (Committee member) / Arizona State University (Publisher)
Created2011
Description
Advancements in computer vision and machine learning have added a new dimension to remote sensing applications with the aid of imagery analysis techniques. Applications such as autonomous navigation and terrain classification which make use of image classification techniques are challenging problems and research is still being carried out to find better solutions. In this thesis, a novel method is proposed which uses image registration techniques to provide better image classification. This method reduces the error rate of classification by performing image registration of the images with the previously obtained images before performing classification. The motivation behind this is the fact that images that are obtained in the same region which need to be classified will not differ significantly in characteristics. Hence, registration will provide an image that matches closer to the previously obtained image, thus providing better classification. To illustrate that the proposed method works, naïve Bayes and iterative closest point (ICP) algorithms are used for the image classification and registration stages respectively. This implementation was tested extensively in simulation using synthetic images and using a real life data set called the Defense Advanced Research Project Agency (DARPA) Learning Applied to Ground Robots (LAGR) dataset. The results show that the ICP algorithm does help in better classification with Naïve Bayes by reducing the error rate by an average of about 10% in the synthetic data and by about 7% on the actual datasets used.
ContributorsMuralidhar, Ashwini (Author) / Saripalli, Srikanth (Thesis advisor) / Papandreou-Suppappola, Antonia (Committee member) / Turaga, Pavan (Committee member) / Arizona State University (Publisher)
Created2011
Description
There is an inexorable link between structure and stress, both of which require study in order to truly understand the physics of thin films. To further our knowledge of thin films, the relationship between structure and stress development was examined in three separate systems in vacuum. The first was continued copper thin film growth in ultra-high vacuum after adsorption of a sub-monolayer quantity of oxygen. Results showed an increase in compressive stress generation, and theory was proposed to explain the additional compressive stress within the films. The second system explored was the adsorption of carbon monoxide on the platinum {111} surface in vacuum. The experiments displayed a correlation between known structural developments in the adsorbed carbon monoxide adlayer and the surface stress state of the system. The third system consisted of the growth and annealing stresses of ice thin films at cryogenic temperatures in vacuum. It was shown that the growth stresses are clearly linked to known morphology development from literature, with crystalline ice developing compressive and amorphous ice developing tensile stresses respectively, and that amorphous ice films develop additional tensile stresses upon annealing.
ContributorsKennedy, Jordan (Author) / Friesen, Cody (Thesis advisor) / Sieradzki, Karl (Committee member) / Crozier, Peter (Committee member) / Arizona State University (Publisher)
Created2011
Description
In this thesis the performance of a Hybrid AC System (HACS) is modeled and optimized. The HACS utilizes solar photovoltaic (PV) panels to help reduce the demand from the utility during peak hours. The system also includes an ice Thermal Energy Storage (TES) tank to accumulate cooling energy during off-peak hours. The AC runs continuously on grid power during off-peak hours to generate cooling for the house and to store thermal energy in the TES. During peak hours, the AC runs on the power supplied from the PV, and cools the house along with the energy stored in the TES. A higher initial cost is expected due to the additional components of the HACS (PV and TES), but a lower operational cost due to higher energy efficiency, energy storage and renewable energy utilization. A house cooled by the HACS will require a smaller size AC unit (about 48% less in the rated capacity), compared to a conventional AC system. To compare the cost effectiveness of the HACS with a regular AC system, time-of-use (TOU) utility rates are considered, as well as the cost of the system components and the annual maintenance. The model shows that the HACS pays back its initial cost of $28k in about 6 years with an 8% APR, and saves about $45k in total cost when compared to a regular AC system that cools the same house for the same period of 6 years.
ContributorsJubran, Sadiq (Author) / Phelan, Patrick (Thesis advisor) / Calhoun, Ronald (Committee member) / Trimble, Steve (Committee member) / Arizona State University (Publisher)
Created2011
Description
ABSTRACT The behavior of the fission products, as they are released from fission events during nuclear reaction, plays an important role in nuclear fuel performance. Fission product release can occur through grain boundary (GB) at low burnups; therefore, this study simulates the mass transport of fission gases in a 2-D GB network to look into the effects of GB characteristics on this phenomenon, with emphasis on conditions that can lead to percolation. A finite element model was created based on the microstructure of a depleted UO2 sample characterized by Electron Backscattering Diffraction (EBSD). The GBs were categorized into high (D2), low (D1) and bulk diffusivity (Dbulk) based on their misorientation angles and Coincident Site Lattice (CSL) types. The simulation was run using different diffusivity ratios (D2/Dbulk) ranging from 1 to 10^8. The model was set up in three ways: constant temperature case, temperature gradient effects and window methods that mimic the environments in a Light Water Reactor (LWR). In general, the formation of percolation paths was observed at a ratio higher than 10^4 in the measured GB network, which had a 68% fraction of high diffusivity GBs. The presence of temperature gradient created an uneven concentration distribution and decreased the overall mass flux. Finally, radial temperature and fission gas concentration profiles were obtained for a fuel pellet in operation using an approximate 1-D model. The 100 µm long microstructurally explicit model was used to simulate, to the scale of a real UO2 pellet, the mass transport at different radial positions, with boundary conditions obtained from the profiles. Stronger percolation effects were observed at the intermediate and periphery position of the pellet. The results also showed that highest mass flux happens at the edge of a pellet at steady state to accommodate for the sharp concentration drop.
ContributorsLim, Harn Chyi (Author) / Peralta, Pedro (Thesis advisor) / Dey, Sandwip (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created2011
Biological and immunological characterization of plant-produced HIV-1 Gag/dgp41 virus-like particles
Description
Anti-retroviral drugs and AIDS prevention programs have helped to decrease the rate of new HIV-1 infections in some communities, however, a prophylactic vaccine is still needed to control the epidemic world-wide. Despite over two decades of research, a vaccine against HIV-1 remains elusive, although recent clinical trials have shown promising results. Recent successes have focused on highly conserved, mucosally-targeted antigens within HIV-1 such as the membrane proximal external region (MPER) of the envelope protein, gp41. MPER has been shown to play critical roles in the viral mucosal transmission, though this peptide is not immunogenic on its own. Gag is a structural protein configuring the enveloped virus particles, and has been suggested to constitute a target of the cellular immunity potentially controlling the viral load. It was hypothesized that HIV-1 enveloped virus-like particles (VLPs) consisting of Gag and a deconstructed form of gp41 comprising the MPER, transmembrane, and cytoplasmic domains (dgp41) could be expressed in plants. Plant-optimized HIV-1 genes were constructed and expressed in Nicotiana benthamiana by stable transformation, or transiently using a tobacco mosaic virus-based expression system or a combination of both. Results of biophysical, biochemical and electron microscopy characterization demonstrated that plant cells could support not only the formation of HIV-1 Gag VLPs, but also the accumulation of VLPs that incorporated dgp41. These particles were purified and utilized in mice immunization experiments. Prime-boost strategies combining systemic and mucosal priming with systemic boosting using two different vaccine candidates (VLPs and CTB-MPR - a fusion of MPER and the B-subunit of cholera toxin) were administered to BALB/c mice. Serum antibody responses against both the Gag and gp41 antigens could be elicited in mice systemically primed with VLPs and these responses could be recalled following systemic boosting with VLPs. In addition, mucosal priming with VLPs allowed for a robust boosting response against Gag and gp41 when boosted with either candidate. Functional assays of these antibodies are in progress to test the antibodies' effectiveness in neutralizing and preventing mucosal transmission of HIV-1. This immunogenicity of plant-based Gag/dgp41 VLPs represents an important milestone on the road towards a broadly-efficacious and inexpensive subunit vaccine against HIV-1.
ContributorsKessans, Sarah (Author) / Mor, Tsafrir S (Thesis advisor) / Matoba, Nobuyuki (Committee member) / Mason, Hugh (Committee member) / Hogue, Brenda (Committee member) / Fromme, Petra (Committee member) / Arizona State University (Publisher)
Created2011
Description
Africa is misrepresented and mis-imaged in the western media. Because of this, notions and beliefs about atrocities that take place on the continent lack context, leaving people to think that Africa is a place of misery, darkness and despair; a monolithic land where evil resides. The image of Africa as the "heart of darkness" was conjured following the Joseph Conrad novel and the idea of Africa as the "Dark Continent" still pervades Western thought. This is an inadequate understanding of Africa, and lacks the context to comprehend why many of the atrocities in Africa occur. I will explore two atrocities in Africa, the 1994 Rwanda Genocide and child slavery on Lake Volta in Ghana. I believe that both these examples reflect how the label of evil is insufficient to describe the circumstances around each atrocity. In order to understand such events we must understand the part that colonialism and poverty play in the disruption of pan-African culture. The "evils" of these two phenomenon, are in many cases the result of the Western world's past involvement in Africa and are remnants and extensions of the disruption caused.
ContributorsBork, Paul (Author) / Simmons, William P (Thesis advisor) / Erfani, Julie (Committee member) / Anokye, Duku A (Committee member) / Arizona State University (Publisher)
Created2011
Description
One in six children in the developing world is engaged in Child labor. Child labor is considered an issue that violates children's rights in many countries and Iraq is no exception. In 2004, Iraq had 1,300,000 children between the ages of eight and sixteen years engaged in work (UNICEF.com, 2004). This study identifies the major causes of child labor in Iraq and investigates the consequences of this issue. In this thesis I draw on the comparison of former regimes in Iraq and Egypt and how those regimes were mistreating their citizens by making them live under poverty and oppression while they were receiving support from the U.S. Poverty is the major cause behind Iraqi children engaging in work. I used the data I collected in Iraq, in the city of Nasiriyah, of 28 working children to explain the relationship between poverty, students drop out of school, family attitude towards education and the child engagement in work. At the end of the thesis I offer a list of recommendations to try to address the problem of child labor in Iraq. The recommendations and regulations are for Iraqi government and the NGOs to take into consideration in trying to resolve and regulate the issue of child labor to rescue the children in Iraq from more exploitation in the future.
ContributorsAl-Taee, Hawraa F (Author) / Elenes, C (Thesis advisor) / Erfani, Julie M (Committee member) / Ali, Souad (Committee member) / Arizona State University (Publisher)
Created2011