Matching Items (95)
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Description
ABSTRACT Peptide microarrays may prove to be a powerful tool for proteomics research and clinical diagnosis applications. Fodor et al. and Maurer et al. have shown proof-of-concept methods of light- and electrochemically-directed peptide microarray fabrication on glass and semiconductor microchips respectively. In this work, peptide microarray fabrication based on the

ABSTRACT Peptide microarrays may prove to be a powerful tool for proteomics research and clinical diagnosis applications. Fodor et al. and Maurer et al. have shown proof-of-concept methods of light- and electrochemically-directed peptide microarray fabrication on glass and semiconductor microchips respectively. In this work, peptide microarray fabrication based on the abovementioned techniques were optimized. In addition, MALDI mass spectrometry based peptide synthesis characterization on semiconductor microchips was developed and novel applications of a CombiMatrix (CBMX) platform for electrochemically controlled synthesis were explored. We have investigated performance of 2-(2-nitrophenyl)propoxycarbonyl (NPPOC) derivatives as photo-labile protecting group. Specifically, influence of substituents on 4 and 5 positions of phenyl ring of NPPOC group on the rate of photolysis and the yield of the amine was investigated. The results indicated that substituents capable of forming a π-network with the nitro group enhanced the rate of photolysis and yield. Once such properly substituted NPPOC groups were used, the rate of photolysis/yield depended on the nature of protected amino group indicating that a different chemical step during the photo-cleavage process became the rate limiting step. We also focused on electrochemically-directed parallel synthesis of high-density peptide microarrays using the CBMX technology referred to above which uses electrochemically generated acids to perform patterned chemistry. Several issues related to peptide synthesis on the CBMX platform were studied and optimized, with emphasis placed on the reactions of electro-generated acids during the deprotection step of peptide synthesis. We have developed a MALDI mass spectrometry based method to determine the chemical composition of microarray synthesis, directly on the feature. This method utilizes non-diffusional chemical cleavage from the surface, thereby making the chemical characterization of high-density microarray features simple, accurate, and amenable to high-throughput. CBMX Corp. has developed a microarray reader which is based on electro-chemical detection of redox chemical species. Several parameters of the instrument were studied and optimized and novel redox applications of peptide microarrays on CBMX platform were also investigated using the instrument. These include (i) a search of metal binding catalytic peptides to reduce overpotential associated with water oxidation reaction and (ii) an immobilization of peptide microarrays using electro-polymerized polypyrrole.
ContributorsKumar, Pallav (Author) / Woodbury, Neal (Thesis advisor) / Allen, James (Committee member) / Johnston, Stephen (Committee member) / Arizona State University (Publisher)
Created2013
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Description

Background

The transition from the home to college is a phase in which emerging adults shift toward more unhealthy eating and physical activity patterns, higher body mass indices, thus increasing risk of overweight/obesity. Currently, little is understood about how changing friendship networks shape weight gain behaviors. This paper describes the

Background

The transition from the home to college is a phase in which emerging adults shift toward more unhealthy eating and physical activity patterns, higher body mass indices, thus increasing risk of overweight/obesity. Currently, little is understood about how changing friendship networks shape weight gain behaviors. This paper describes the recruitment, data collection, and data analytic protocols for the SPARC (Social impact of Physical Activity and nutRition in College) study, a longitudinal examination of the mechanisms by which friends and friendship networks influence nutrition and physical activity behaviors and weight gain in the transition to college life.

Methods

The SPARC study aims to follow 1450 university freshmen from a large university over an academic year, collecting data on multiple aspects of friends and friendship networks. Integrating multiple types of data related to student lives, ecological momentary assessments (EMAs) are administered via a cell phone application, devilSPARC. EMAs collected in four 1-week periods (a total of 4 EMA waves) are integrated with linked data from web-based surveys and anthropometric measurements conducted at four times points (for a total of eight data collection periods including EMAs, separated by ~1 month). University databases will provide student card data, allowing integration of both time-dated data on food purchasing, use of physical activity venues, and geographical information system (GIS) locations of these activities relative to other students in their social networks.

Discussion

Findings are intended to guide the development of more effective interventions to enhance behaviors among college students that protect against weight gain during college.

ContributorsBruening, Meg (Author) / Ohri-Vachaspati, Punam (Author) / Brewis, Alexandra (Author) / Laska, Melissa (Author) / Todd, Michael (Author) / Hruschka, Daniel (Author) / Schaefer, David (Author) / Whisner, Corrie M (Author) / Dunton, Genevieve (Author)
Created2016-08-30
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Computational models have long been used to describe and predict the outcome of complex immunological processes. The dissertation work described here centers on the construction of multiscale computational immunology models that derives biological insights at the population, systems, and atomistic levels. First, SARS-CoV-2 mortality is investigated through the lens of

Computational models have long been used to describe and predict the outcome of complex immunological processes. The dissertation work described here centers on the construction of multiscale computational immunology models that derives biological insights at the population, systems, and atomistic levels. First, SARS-CoV-2 mortality is investigated through the lens of the predicted robustness of CD8+ T cell responses in 23 different populations. The robustness of CD8+ T cell responses in a given population was modeled by predicting the efficiency of endemic MHC-I protein variants to present peptides derived from SARS-CoV-2 proteins to circulating T cells. To accomplish this task, an algorithm, called EnsembleMHC, was developed to predict viral peptides with a high probability of being recognized by CD T cells. It was discovered that there was significant variation in the efficiency of different MHC-I protein variants to present SARS-CoV-2 derived peptides, and countries enriched with variants with high presentation efficiency had significantly lower mortality rates. Second, a biophysics-based MHC-I peptide prediction algorithm was developed. The MHC-I protein is the most polymorphic protein in the human genome with polymorphisms in the peptide binding causing striking changes in the amino acid compositions, or binding motifs, of peptide species capable of stable binding. A deep learning model, coined HLA-Inception, was trained to predict peptide binding using only biophysical properties, namely electrostatic potential. HLA-Inception was shown to be extremely accurate and efficient at predicting peptide binding motifs and was used to determine the peptide binding motifs of 5,821 MHC-I protein variants. Finally, the impact of stalk glycosylations on NL63 protein dynamics was investigated. Previous data has shown that coronavirus crown glycans play an important role in immune evasion and receptor binding, however, little is known about the role of the stalk glycans. Through the integration of computational biology, experimental data, and physics-based simulations, the stalk glycans were shown to heavily influence the bending angle of spike protein, with a particular emphasis on the glycan at position 1242. Further investigation revealed that removal of the N1242 glycan significantly reduced infectivity, highlighting a new potential therapeutic target. Overall, these investigations and associated innovations in integrative modeling.
ContributorsWilson, Eric Andrew (Author) / Anderson, Karen (Thesis advisor) / Singharoy, Abhishek (Thesis advisor) / Woodbury, Neal (Committee member) / Sulc, Petr (Committee member) / Arizona State University (Publisher)
Created2022
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Description
Social norms are unwritten behavioral codes. They direct individual behaviors, facilitate interpersonal coordination and cooperation, and lead to variation among human populations. Understanding how norms are maintained and how they change is critical for understanding human evolutionary psychology, social organization, and cultural change. This dissertation uses a mathematical model and

Social norms are unwritten behavioral codes. They direct individual behaviors, facilitate interpersonal coordination and cooperation, and lead to variation among human populations. Understanding how norms are maintained and how they change is critical for understanding human evolutionary psychology, social organization, and cultural change. This dissertation uses a mathematical model and a field study to answer two questions: First, what factors determine the content and dynamics of a social norm? Second, how do people make decisions in a normative context? The mathematical model finds that contrary to the popular belief that even arbitrary or deleterious social norms can be maintained once established because deviants suffer coordination failures and social sanctions, norms with continuously varying options cannot be maintained by the pressure to do what others do. Instead, continuous norms evolve to the optimum determined by environmental pressure, individual preferences, or cognitive processes. Therefore, the content of norms across human societies may be less historically constrained than previously assumed. The field study shows that unlike what rational choice theory predicts, people in a small-scale subsistence society do not calculate the ecological and social payoffs of different behaviors in a normative context, even when they have the information to do so. Instead, they rely heavily on social information about what others do. This decision-making algorithm, together with mental categorization that ignores small deviations, and cognitive biases that favor the division prescribed by the norm, maintain an ecologically inefficient and widely disliked cooperative surplus division norm in a Derung village, Dizhengdang, in Yunnan, China.
ContributorsYan, Minhua (Author) / Boyd, Robert (Thesis advisor) / Mathew, Sarah (Thesis advisor) / Hruschka, Daniel (Committee member) / Arizona State University (Publisher)
Created2023
Description

Existing research has shown that both ethnic discrimination and household wealth can shape child well-being and development. However, little work examines ethnic discrimination and its relation to income in predicting childhood health globally. This study explores two possible explanations for disparities in infant mortality between ethnic groups across countries worldwide.

Existing research has shown that both ethnic discrimination and household wealth can shape child well-being and development. However, little work examines ethnic discrimination and its relation to income in predicting childhood health globally. This study explores two possible explanations for disparities in infant mortality between ethnic groups across countries worldwide. The first is an explanation based on wealth differentials across ethnic groups. The second is the impact of forms of ethnic discrimination such as past lethal violence or forced labor experienced by the group. This study examines the correlation between ethnic discrimination and infant mortality using household wealth as a covariate. Analyses focused on 266 ethnicities in 40 low- and middle-income countries globally, drawing on infant mortality data from Demographic and Health Surveys and data on ethnic discrimination compiled by the Inclusive Human Learning Lab at Arizona State University. Findings without the inclusion of household wealth show that ethnic groups that predominantly spoke the state language had significantly lower rates of infant mortality. However, this trend disappears when income is added as a covariate. No other measures of discrimination or privilege were associated with infant mortality. Across all analyses, the wealth of the ethnic group was a significant predictor of infant mortality. Future studies should examine whether these trends persist in high-income countries, and whether the general lack of association of discrimination and privilege variables with infant mortality is influenced by how the variables were coded.

ContributorsUn, Anthony (Author) / Hruschka, Daniel (Thesis director) / Drake, Alexandria (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Human Evolution & Social Change (Contributor)
Created2023-05
Description

For African countries during the 1960s and 70s, decolonization marked the first step in a slow crawl toward complete independence. For Western powers and the Soviet Union, however, decolonization presented an opportunity to exert new influence over countries in desperate need of aid, investment, experts, and trade. Amidst the backdro

For African countries during the 1960s and 70s, decolonization marked the first step in a slow crawl toward complete independence. For Western powers and the Soviet Union, however, decolonization presented an opportunity to exert new influence over countries in desperate need of aid, investment, experts, and trade. Amidst the backdrop of increasing Cold War tensions, the US and USSR used foreign aid to pressure development according to either capitalist or Marxist agendas. Thus, sub-Saharan Africa became a battleground of proxy wars and neocolonialism. The Cold War superpowers would back opposing regimes in Angola and prop up, oust, or assassinate leaders in Ghana, Democratic Republic of the Congo, and Tanzania. This disrupted natural political development and created instability and violence, which was compounded by the arrival of the AIDS epidemic in the mid-1980s. AIDS ravaged African societies and destroyed the remaining fibers of leadership. The disease illuminated harsh historical realities as it spread among the conflict-stricken countries of sub-Saharan Africa. The goal of this thesis is to analyze the motivations behind US and USSR foreign aid during the Cold War, understand how their involvement halted the natural progression of pan-Africanism and leadership in newly-independent African countries, and link the resulting violence to the devastation of the AIDS crisis twenty years later. It begins with a look at European colonization in sub-Saharan Africa and traces the legacy of western influence in the region. The paper will then analyze specific examples of the consequences of historical interference, such as in the Angolan Civil War, the Congo Crisis, and the Rwandan genocide. It will introduce the AIDS crisis—coincident with major civil conflict and the end of the Cold War—and reveal the foreign aid response of the international community in the late 1990s and early 2000s, once Cold War-era pressures were gone. Through realizing the continued impact and spread of HIV/AIDS, the objective of this paper is to present a comprehensive view of the modern-day consequences of historical interference.

ContributorsStaker, Gabrielle (Author) / Niebuhr, Robert (Thesis director) / Hruschka, Daniel (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Human Evolution & Social Change (Contributor)
Created2023-05
Description

The electronic dance music (EDM) rave community prides itself in fostering an all- accepting subculture for people to unite in style, song, and dance. Based on the principles of Peace, Love, Unity, and Respect (PLUR), rave events have unique and colorful themes, bass levels you can feel in your heart,

The electronic dance music (EDM) rave community prides itself in fostering an all- accepting subculture for people to unite in style, song, and dance. Based on the principles of Peace, Love, Unity, and Respect (PLUR), rave events have unique and colorful themes, bass levels you can feel in your heart, bright and invigorating laser light shows, and in many cases, a heavy presence of both legal and illegal drug use. Because of the association with illegal substances, open discussions regarding drug presence, use, and harm reduction have been stigmatized and limited in the rave community. This study aims to evaluate the current level of knowledge and attitudes regarding drug presence and harm reduction among “ravers.” All participants were required to be of 18 years of age or older and have attended at least 1 EDM event in the past 5 years. The study involved two stages: (1) collecting qualitative data through in person, phone call, or Zoom interviews (n=14), and (2) collecting quantitative data through closed-ended, anonymous surveys via QuestionPro (n=64). The results indicate that a significant portion of participants in both stages express a desire for easily accessible harm reduction information and increased measures prior to and at EDM events. Starting an open dialogue about drug use and harm reduction efforts within this subculture could help create a safer environment and reduce the negative consequences of drug use.

ContributorsOrillo, Rebecca Marie (Author) / Hruschka, Daniel (Thesis director) / Olive, Foster (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2023-05
Description

The term “Iraqi American” defines any person of Iraqi origin who is residing in the United States. From 1960 until 2014, Iraq experienced numerous armed conflicts and international sanctions. As a result, a great surge of Iraqis migrated out of the country to seek refuge elsewhere. The United States alone

The term “Iraqi American” defines any person of Iraqi origin who is residing in the United States. From 1960 until 2014, Iraq experienced numerous armed conflicts and international sanctions. As a result, a great surge of Iraqis migrated out of the country to seek refuge elsewhere. The United States alone currently houses about 400,000+ persons of Iraqi descent, many of whom identify as its citizens. Despite that, Iraqi Americans remain severely understudied. Therefore, this study aims to understand the cultural barriers Iraqi American women face while seeking healthcare in the United States, and how these barriers can impact their behaviors. I collected data via semi-structured interviews with eight Iraqi American women. In this study, I identified five major themes that contributed to women’s healthcare seeking behaviors: societal/familial pressures, staying “pure,” shame associated with performing medical procedures, taboo surrounding discussions of female health conditions, and issues regarding being in the presence of male doctors. Many of these themes involved cultural stigmas and pointed to potential pathways to destigmatize women’s healthcare in the community. This study acts as an initiative to understanding Iraqi Americans better and lays groundwork for further research.

ContributorsRahee, Hajer (Author) / Hruschka, Daniel (Thesis director) / Drake, Alexandria (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Human Evolution & Social Change (Contributor)
Created2023-05
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Contact tracing was deployed widely during the COVID-19 pandemic to attempt to stop the spread of SARS Co-V-2. This dissertation investigates the research on contact tracing from a scientometric perspective and looks qualitatively at how case investigators and contact tracers conducted public health practice during the pandemic. Through

Contact tracing was deployed widely during the COVID-19 pandemic to attempt to stop the spread of SARS Co-V-2. This dissertation investigates the research on contact tracing from a scientometric perspective and looks qualitatively at how case investigators and contact tracers conducted public health practice during the pandemic. Through approaching the public health practice of contact tracing from both a broad, top-down angle, and an on the ground experiential approach, this dissertation provides insight into the issues facing contact tracing as a public health tool.
ContributorsWhite, Alexandra C. (Author) / Jehn, Megan (Thesis advisor) / Hruschka, Daniel (Committee member) / Gaughan, Monica (Committee member) / Arizona State University (Publisher)
Created2022
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The purpose of this report is to review the current literature concerning management of the COVID-19 pandemic in homeless populations, and to use it to analyze the specific interventions established in Maricopa County—such as those aimed at education, vaccination and testing, and maintaining continuity of care. In doing so, I

The purpose of this report is to review the current literature concerning management of the COVID-19 pandemic in homeless populations, and to use it to analyze the specific interventions established in Maricopa County—such as those aimed at education, vaccination and testing, and maintaining continuity of care. In doing so, I hope to illustrate the unique challenges faced by people experiencing homelessness, provide context for disparities in health outcome, and inform action for both the ongoing pandemic and future outbreaks
ContributorsNewell, James (Author) / Gaughan, Monica (Thesis director) / Hruschka, Daniel (Committee member) / Barrett, The Honors College (Contributor) / School of Human Evolution & Social Change (Contributor) / School of Life Sciences (Contributor) / Watts College of Public Service & Community Solut (Contributor)
Created2022-05