Matching Items (238)
Filtering by

Clear all filters

151929-Thumbnail Image.png
Description
The entire history of HIV-1 is hidden in its ten thousand bases, where information regarding its evolutionary traversal through the human population can only be unlocked with fine-scale sequence analysis. Measurable footprints of mutation and recombination have imparted upon us a wealth of knowledge, from multiple chimpanzee-to-human transmissions to patterns

The entire history of HIV-1 is hidden in its ten thousand bases, where information regarding its evolutionary traversal through the human population can only be unlocked with fine-scale sequence analysis. Measurable footprints of mutation and recombination have imparted upon us a wealth of knowledge, from multiple chimpanzee-to-human transmissions to patterns of neutralizing antibody and drug resistance. Extracting maximum understanding from such diverse data can only be accomplished by analyzing the viral population from many angles. This body of work explores two primary aspects of HIV sequence evolution, point mutation and recombination, through cross-sectional (inter-individual) and longitudinal (intra-individual) investigations, respectively. Cross-sectional Analysis: The role of Haiti in the subtype B pandemic has been hotly debated for years; while there have been many studies, up to this point, no one has incorporated the well-known mechanism of retroviral recombination into their biological model. Prior to the use of recombination detection, multiple analyses produced trees where subtype B appears to have first entered Haiti, followed by a jump into the rest of the world. The results presented here contest the Haiti-first theory of the pandemic and instead suggest simultaneous entries of subtype B into Haiti and the rest of the world. Longitudinal Analysis: Potential N-linked glycosylation sites (PNGS) are the most evolutionarily dynamic component of one of the most evolutionarily dynamic proteins known to date. While the number of mutations associated with the increase or decrease of PNGS frequency over time is high, there are a set of relatively stable sites that persist within and between longitudinally sampled individuals. Here, I identify the most conserved stable PNGSs and suggest their potential roles in host-virus interplay. In addition, I have identified, for the first time, what may be a gp-120-based environmental preference for N-linked glycosylation sites.
ContributorsHepp, Crystal Marie, 1981- (Author) / Rosenberg, Michael S. (Thesis advisor) / Hedrick, Philip (Committee member) / Escalante, Ananias (Committee member) / Kumar, Sudhir (Committee member) / Arizona State University (Publisher)
Created2013
156824-Thumbnail Image.png
Description
Recent technology advancements in photovoltaics have enabled crystalline silicon (c-Si) solar cells to establish outstanding photoconversion efficiency records. Remarkable progresses in research and development have been made both on the silicon feedstock quality as well as the technology required for surface passivation, the two dominant sources of performance loss via

Recent technology advancements in photovoltaics have enabled crystalline silicon (c-Si) solar cells to establish outstanding photoconversion efficiency records. Remarkable progresses in research and development have been made both on the silicon feedstock quality as well as the technology required for surface passivation, the two dominant sources of performance loss via recombination of photo-generated charge carriers within advanced solar cell architectures.

As these two aspects of the solar cell framework improve, the need for a thorough analysis of their respective contribution under varying operation conditions has emerged along with challenges related to the lack of sensitivity of available characterization techniques. The main objective of my thesis work has been to establish a deep understanding of both “intrinsic” and “extrinsic” recombination processes that govern performance in high-quality silicon absorbers. By studying each recombination mechanism as a function of illumination and temperature, I strive to identify the lifetime limiting defects and propose a path to engineer the ultimate silicon solar cell.

This dissertation presents a detailed description of the experimental procedure required to deconvolute surface recombination contributions from bulk recombination contributions when performing lifetime spectroscopy analysis. This work proves that temperature- and injection-dependent lifetime spectroscopy (TIDLS) sensitivity can be extended to impurities concentrations down to 109 cm-3, orders of magnitude below any other characterization technique available today. A new method for the analysis of TIDLS data denominated Defect Parameters Contour Mapping (DPCM) is presented with the aim of providing a visual and intuitive tool to identify the lifetime limiting impurities in silicon material. Surface recombination velocity results are modelled by applying appropriate approaches from literature to our experimentally evaluated data, demonstrating for the first time their capability to interpret temperature-dependent data. In this way, several new results are obtained which solve long disputed aspects of surface passivation mechanisms. Finally, we experimentally evaluate the temperature-dependence of Auger lifetime and its impact on a theoretical intrinsically limited solar cell. These results decisively point to the need for a new Auger lifetime parameterization accounting for its temperature-dependence, which would in turn help understand the ultimate theoretical efficiency limit for a solar cell under real operation conditions.
ContributorsBernardini, Simone (Author) / Bertoni, Mariana I (Thesis advisor) / Coletti, Gianluca (Committee member) / Bowden, Stuart (Committee member) / Alford, Terry (Committee member) / Arizona State University (Publisher)
Created2018
137224-Thumbnail Image.png
Description
The ability to edit chromosomal regions is an important tool for the study of gene function and the ability to engineer synthetic gene networks. CRISPR-Cas systems, a bacterial RNA-guided immune system against foreign nucleic acids, have recently been engineered for a plethora of genome engineering and transcriptional regulation applications. Here

The ability to edit chromosomal regions is an important tool for the study of gene function and the ability to engineer synthetic gene networks. CRISPR-Cas systems, a bacterial RNA-guided immune system against foreign nucleic acids, have recently been engineered for a plethora of genome engineering and transcriptional regulation applications. Here we employ engineered variants of CRISPR systems in proof-of-principle experiments demonstrating the ability of CRISPR-Cas derived single-DNA-strand cutting enzymes (nickases) to direct host-cell genomic recombination. E.coli is generally regarded as a poorly recombinogenic host with double-stranded DNA breaks being highly lethal. However, CRISPR-guided nickase systems can be easily programmed to make very precise, non-lethal, incisions in genomic regions directing both single reporter gene and larger-scale recombination events deleting up to 36 genes. Genome integrated repetitive elements of variable sizes can be employed as sites for CRISPR induced recombination. We project that single-stranded based editing methodologies can be employed alongside preexisting genome engineering techniques to assist and expedite metabolic engineering and minimalized genome research.
ContributorsStandage-Beier, Kylie S (Author) / Wang, Xiao (Thesis director) / Haynes, Karmella (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
147879-Thumbnail Image.png
Description

Extreme heat is the deadliest weather and climate-related hazard in the United States, and the threat it poses to urban residents is rising. City planners increasingly recognize these risks and are taking action to mitigate them. However, the COVID-19 pandemic has disrupted many plans. Building on a

Extreme heat is the deadliest weather and climate-related hazard in the United States, and the threat it poses to urban residents is rising. City planners increasingly recognize these risks and are taking action to mitigate them. However, the COVID-19 pandemic has disrupted many plans. Building on a previous survey which queried city planners from across the United States about how concerned they were about extreme heat, and their heat management efforts. This thesis examines how these perceptions and efforts have changed in the face of the COVID-19 pandemic. In general, it was found that public spaces which would typically have been used to shelter individuals from extreme heat conditions were closed to mitigate close-contact and to encourage social distancing. Furthermore, priorities were changed as the presence of the virus became commonplace, with plans being altered, delayed, or shelved to diverge more time and effort towards the crisis at hand. Working environments and conditions also changed, which in several cases led to technological shortcomings, resulting in further delays. Finally, most planners had attained a surface-level understanding of which socio-economic groups were most impacted by both COVID-19 and extreme heat, in congruence with the current literature written on the topic. Generally, it appears that planners feel that the impact of COVID-19 on heat planning efforts has been limited.

ContributorsNorris, Walker Yale (Author) / Meerow, Sara (Thesis director) / Keith, Ladd (Committee member) / Dean, W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
147893-Thumbnail Image.png
Description

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts and aspects. The business agility of the lab and it’s quickness to innovation has allowed the lab to enjoy great success. Looking into the future, the laboratory has a promising future and will need to answer many questions to remain the premier COVID-19 testing institution in Arizona.

ContributorsQian, Michael (Co-author) / Cosgrove, Samuel (Co-author) / English, Corinne (Co-author) / Agee, Claire (Co-author) / Mattson, Kyle (Co-author) / Compton, Carolyn (Thesis director) / Schneller, Eugene (Committee member) / School of Accountancy (Contributor) / Department of Finance (Contributor) / Department of Information Systems (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
147895-Thumbnail Image.png
Description

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts and aspects. The business agility of the lab and it’s quickness to innovation has allowed the lab to enjoy great success. Looking into the future, the laboratory has a promising future and will need to answer many questions to remain the premier COVID-19 testing institution in Arizona.

ContributorsEnglish, Corinne (Co-author) / Cosgrove, Samuel (Co-author) / Mattson, Kyle (Co-author) / Agee, Claire (Co-author) / Qian, Michael (Co-author) / Compton, Carolyn (Thesis director) / Schneller, Eugene (Committee member) / Department of Information Systems (Contributor) / Department of Supply Chain Management (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
147906-Thumbnail Image.png
Description

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts and aspects. The business agility of the lab and it’s quickness to innovation has allowed the lab to enjoy great success. Looking into the future, the laboratory has a promising future and will need to answer many questions to remain the premier COVID-19 testing institution in Arizona.

ContributorsAgee, Claire (Co-author) / English, Corinne (Co-author) / Mattson, Kyle (Co-author) / Qian, Michael (Co-author) / Cosgrove, Samuel (Co-author) / Compton, Carolyn (Thesis director) / Schneller, Eugene (Committee member) / Department of Finance (Contributor) / Department of Supply Chain Management (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
147907-Thumbnail Image.png
Description

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts

For our project, we explored the growth of the ASU BioDesign Clinical Testing Laboratory (ABCTL) from a standard university research lab to a COVID-19 testing facility through a business lens. The lab has pioneered the saliva-test in the Western United States. This thesis analyzes the laboratory from various business concepts and aspects. The business agility of the lab and it’s quickness to innovation has allowed the lab to enjoy great success. Looking into the future, the laboratory has a promising future and will need to answer many questions to remain the premier COVID-19 testing institution in Arizona.

ContributorsMattson, Kyle (Co-author) / Agee, Claire (Co-author) / English, Corinne (Co-author) / Cosgrove, Samuel (Co-author) / Compton, Carolyn (Thesis director) / Schneller, Eugene (Committee member) / Department of Marketing (Contributor) / Department of Supply Chain Management (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
148381-Thumbnail Image.png
Description

Healthcare facilities are essential for any community, and they must stay up-to-date with the latest equipment and technology. They provide necessary resources for keeping populations healthy and safe. In order to provide healthcare services, these healthcare facilities must be adequately equipped with appropriate physical capital as well as software to

Healthcare facilities are essential for any community, and they must stay up-to-date with the latest equipment and technology. They provide necessary resources for keeping populations healthy and safe. In order to provide healthcare services, these healthcare facilities must be adequately equipped with appropriate physical capital as well as software to meet the demands of their patients. Healthcare capital equipment planning involves building up a facility with all it’s equipment and is a part of the healthcare supply chain. Attainia is a healthcare capital equipment planning software used to assist equipment planners in organizing the procurement of equipment for their projects. Attainia has a large amount of data about the capital equipment supply chain through the Attainia equipment catalog. Analysis of this catalog data reveals different patterns in the spending patterns of capital equipment planners as well as trends in the supplier offerings. Since Attainia itself is a software, Attainia’s users have experience with implementing and integrating software into healthcare IT solutions. Their experiences give some insight into the complex nature of software implementations at healthcare facilities. The COVID-19 pandemic has affected healthcare facilities all over the world. Impacting the supply chain and hitting hospitals’ finances, COVID-19 has drastically changed many parts of the healthcare system. This paper will examine some of these ongoing effects from COVID-19 along with analysis on capital equipment planning, supply chain, and healthcare software implementation.

ContributorsShah, Shailee (Author) / Pye, Jessica (Thesis director) / Roumina, Kavous (Committee member) / School of International Letters and Cultures (Contributor) / Department of Information Systems (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
148391-Thumbnail Image.png
Description

The SARS-CoV-2 (Covid-19) virus has had severe impacts on college students' ways of life. To examine how students were coping and perceiving the Covid-19 pandemic, a secondary analysis of an online survey across the three Arizona public universities investigated students’ knowledge about Covid-19, engagement with preventive strategies, pandemic preparedness and

The SARS-CoV-2 (Covid-19) virus has had severe impacts on college students' ways of life. To examine how students were coping and perceiving the Covid-19 pandemic, a secondary analysis of an online survey across the three Arizona public universities investigated students’ knowledge about Covid-19, engagement with preventive strategies, pandemic preparedness and gauged their risk perception. Results from our analysis indicate that the students were knowledgeable about Covid-19 and were changing their habits and engaging with preventive measures. Results further suggest that students were prepared for the pandemic in terms of resources and were exhibiting high-risk perceptions. The data also revealed that students who were being cautious and engaging with preventive behaviors had a higher risk-perception than individuals who were not. As for individuals who were prepared for the pandemic in terms of supplies, their risk perception was similar to those who did not have supplies. Individuals who were prepared and capable of providing a single caretaker to tend to their sick household members and isolate them in a separate room had a higher risk perception than those who could not. These results can help describe how college students will react to a future significant event, what resources students may be in need of, and how universities can take additional steps to keep their students safe and healthy. The results from this study and recommendations will provide for a stronger and more understanding campus community during times of distress and can improve upon already established university protocols for health crises and even natural disasters.

ContributorsNaqvi, Avina Itrat (Co-author) / Shaikh, Sara (Co-author) / Jehn, Megan (Thesis director) / Adams, Marc (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05