Matching Items (106)
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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
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Ecology has been an actively studied topic recently, along with the rapid development of human microbiota-based technology. Scientists have made remarkable progress using bioinformatics tools to identify species and analyze composition. However, a thorough understanding of interspecies interactions of microbial ecosystems is still lacking, which has been a significant obstacle

Ecology has been an actively studied topic recently, along with the rapid development of human microbiota-based technology. Scientists have made remarkable progress using bioinformatics tools to identify species and analyze composition. However, a thorough understanding of interspecies interactions of microbial ecosystems is still lacking, which has been a significant obstacle in the further development of related technologies. In this work, a genetic circuit design principle with synthetic biology approaches is developed to form two-strain microbial consortia with different inter-strain interactions. The microbial systems are well-defined and inducible. Co-culture experiment results show that our microbial consortia behave consistently with previous ecological knowledge and thus serves as excellent model systems to simulate ecosystems with similar interactions. Colony patterns also emerge when co-culturing multiple species on solid media. With the engineered microbial consortia, image-processing based methods were developed to quantify the shape of co-culture colonies and distinguish microbial consortia with different interactions. Factors that affect the population ratios were identified through induction and variations in the inoculation process. Further time-lapse experiments revealed the basic rules of colony growth, composition variation, patterning, and how spatial factors impact the co-culture colony.
ContributorsChen, Xingwen (Author) / Wang, Xiao (Thesis advisor) / Kuang, Yang (Committee member) / Tian, Xiaojun (Committee member) / Brafman, David (Committee member) / Plaisier, Christopher (Committee member) / Arizona State University (Publisher)
Created2022
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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Annually, approximately 1.7 million people suffer a traumatic brain injury (TBI) in the United States. After initial insult, a TBI persists as a series of molecular and cellular events that lead to cognitive and motor deficits which have no treatment. In addition, the injured brain activates the regenerative niches of

Annually, approximately 1.7 million people suffer a traumatic brain injury (TBI) in the United States. After initial insult, a TBI persists as a series of molecular and cellular events that lead to cognitive and motor deficits which have no treatment. In addition, the injured brain activates the regenerative niches of the adult brain presumably to reduce damage. The subventricular zone (SVZ) niche contains neural progenitor cells (NPCs) that generate astrocytes, oligodendrocyte, and neuroblasts. Following TBI, the injury microenvironment secretes signaling molecules like stromal cell derived factor-1a (SDF-1a). SDF-1a gradients from the injury contribute to the redirection of neuroblasts from the SVZ towards the lesion which may differentiate into neurons and integrate into existing circuitry. This repair mechanism is transient and does not lead to complete recovery of damaged tissue. Further, the mechanism by which SDF-1a gradients reach SVZ cells is not fully understood. To prolong NPC recruitment to the injured brain, exogenous SDF-1a delivery strategies have been employed. Increases in cell recruitment following stroke, spinal cord injury, and TBI have been demonstrated following SDF-1a delivery. Exogenous delivery of SDF-1a is limited by its 28-minute half-life and clearance from the injury microenvironment. Biomaterials-based delivery improves stability of molecules like SDF-1a and offer control of its release. This dissertation investigates SDF-1a delivery strategies for neural regeneration in three ways: 1) elucidating the mechanisms of spatiotemporal SDF-1a signaling across the brain, 2) developing a tunable biomaterials system for SDF-1a delivery to the brain, 3) investigating SDF-1a delivery on SVZ-derived cell migration following TBI. Using in vitro, in vivo, and in silico analyses, autocrine/paracrine signaling was necessary to produce SDF-1a gradients in the brain. Native cell types engaged in autocrine/paracrine signaling. A microfluidics device generated injectable hyaluronic-based microgels that released SDF-1a peptide via enzymatic cleavage. Microgels (±SDF-1a peptide) were injected 7 days post-TBI in a mouse model and evaluated for NPC migration 7 days later using immunohistochemistry. Initial staining suggested complex presence of astrocytes, NPCs, and neuroblasts throughout the frontoparietal cortex. Advancement of chemokine delivery was demonstrated by uncovering endogenous chemokine propagation in the brain, generating new approaches to maximize chemokine-based neural regeneration.
ContributorsHickey, Kassondra (Author) / Stabenfeldt, Sarah E (Thesis advisor) / Holloway, Julianne (Committee member) / Caplan, Michael (Committee member) / Brafman, David (Committee member) / Newbern, Jason (Committee member) / Arizona State University (Publisher)
Created2021
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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 RNA editing enzyme adenosine deaminase acting on double stranded RNA 2 (ADAR2) converts adenosine into inosine in regions of double stranded RNA. Here, it was discovered that this critical function of ADAR2 was dysfunctional in amyotrophic lateral sclerosis (ALS) mediated by the C9orf72 hexanucleotide repeat expansion, the most common

The RNA editing enzyme adenosine deaminase acting on double stranded RNA 2 (ADAR2) converts adenosine into inosine in regions of double stranded RNA. Here, it was discovered that this critical function of ADAR2 was dysfunctional in amyotrophic lateral sclerosis (ALS) mediated by the C9orf72 hexanucleotide repeat expansion, the most common genetic abnormality associated with ALS. Typically a nuclear protein, ADAR2 was localized in cytoplasmic accumulations in postmortem tissue from C9orf72 ALS patients. The mislocalization of ADAR2 was confirmed using immunostaining in a C9orf72 mouse model and motor neurons differentiated from C9orf72 patient induced pluripotent stem cells. Notably, the cytoplasmic accumulation of ADAR2 coexisted in neurons with cytoplasmic accumulations of TAR DNA binding protein 43 (TDP-43). Interestingly, ADAR2 overexpression in mammalian cell lines induced nuclear depletion and cytoplasmic accumulation of TDP-43, reflective of the pathology observed in ALS patients. The mislocalization of TDP-43 was dependent on the catalytic activity of ADAR2 and the ability of TDP-43 to bind directly to inosine containing RNA. In addition, TDP-43 nuclear export was significantly elevated in cells with increased RNA editing. Together these results describe a novel cellular mechanism by which alterations in RNA editing drive the nuclear export of TDP-43 leading to its cytoplasmic mislocalization. Considering the contribution of cytoplasmic TDP-43 to the pathogenesis of ALS, these findings represent a novel understanding of how the formation of pathogenic cytoplasmic TDP-43 accumulations may be initiated. Further research exploring this mechanism will provide insights into opportunities for novel therapeutic interventions.
ContributorsMoore, Stephen Philip (Author) / Sattler, Rita (Thesis advisor) / Zarnescu, Daniela (Committee member) / Brafman, David (Committee member) / Van Keuren-Jensen, Kendall (Committee member) / Mangone, Marco (Committee member) / Arizona State University (Publisher)
Created2021
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Annually approximately 1.5 million Americans suffer from a traumatic brain injury (TBI) increasing the risk of developing a further neurological complication later in life [1-3]. The molecular drivers of the subsequent ensuing pathologies after the initial injury event are vast and include signaling processes that may contribute to neurodegenerative diseases

Annually approximately 1.5 million Americans suffer from a traumatic brain injury (TBI) increasing the risk of developing a further neurological complication later in life [1-3]. The molecular drivers of the subsequent ensuing pathologies after the initial injury event are vast and include signaling processes that may contribute to neurodegenerative diseases such as Alzheimer’s Disease (AD). One such molecular signaling pathway that may link TBI to AD is necroptosis. Necroptosis is an atypical mode of cell death compared with traditional apoptosis, both of which have been demonstrated to be present post-TBI [4-6]. Necroptosis is initiated by tissue necrosis factor (TNF) signaling through the RIPK1/RIPK3/MLKL pathway, leading to cell failure and subsequent death. Prior studies in rodent TBI models report necroptotic activity acutely after injury, within 48 hours. Here, the study objective was to recapitulate prior data and characterize MLKL and RIPK1 cortical expression post-TBI with our lab’s controlled cortical impact mouse model. Using standard immunohistochemistry approaches, it was determined that the tissue sections acquired by prior lab members were of poor quality to conduct robust MLKL and RIPK1 immunostaining assessment. Therefore, the thesis focused on presenting the staining method completed. The discussion also expanded on expected results from these studies regarding the spatial distribution necroptotic signaling in this TBI model.

ContributorsHuber, Kristin (Author) / Stabenfeldt, Sarah (Thesis director) / Brafman, David (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor) / School of Molecular Sciences (Contributor)
Created2022-05