• Migrant Itinerancy: The Hemispheric Politics of Contemporary Undocumented Migration

      Acosta, Abraham; Bejar Lara, Adolfo; Murphy, Kaitlin; Huizar-Hernandez, Anita; Morales, Monica (The University of Arizona., 2020)
      Migrant Itinerancy: The Hemispheric Politics of Contemporary Undocumented Migration analyzes contemporary literary production on the recent intensification of migration patterns in Latin America and the United States. I engage with Latin American and Chicano cultural criticism to examine the neoliberal re-structuration of the nation-state under neoliberalism and its effects on the politics of migration in the region. Migrant Itinerancy argues that undocumented migration exposes the unfounded nature of any figuration of community and reveals the exclusionary logics of contemporary discourses of resistance. I propose the concept of migrant itinerancy as a method of analysis to highlight tensions that reveal how undocumented migration problematizes forms of political subjectivity premised upon notions of identity and belonging. Rather than merely reflecting on the effects of the exclusionary logics of immigration discourse in the region, Migrant Itinerancy asks how the tensions and contradictions at the heart of the politics of migration in the hemisphere open a space of reflection to rearticulate a sense of community premised upon practices of communal care. Through readings of Antonio Ortuño’s La fila india, Luis Alberto Urrea’s The Devil’s Highway, Óscar Martínez’s The Beast, and Valeria Luiselli’s Los niños perdidos, I demonstrate how undocumented migration disrupts residual postcolonial configurations of power, emerging as a political force that demands the redrawing of our current social order. By foregrounding questions of identity, national belonging, human rights, immigration and asylum discourse in a hemispheric context, Migrant Itinerancy reassess the status of the nation-state as principle of social and political organization in times of global migrations.
    • Corporations and Shareholder Political Transparency Activism in the United States

      Earl, Jennifer; Galaskiewicz, Joseph; Zhang, Yongjun; Breiger, Ronald; Fiel, Jeremy (The University of Arizona., 2020)
      Scholars from sociology, political science, management, and economics have long debated the causes and consequences of business in politics. The controversy of corporate money in politics was amplified by the Supreme Court’s landmark 2010 Citizens United decision on electioneering communications. Policymakers, the public, and activists are worried that this might open the corporate campaign spending floodgates, and corporate America may abuse its political power over democracy. Many concerned primary and secondary stakeholders have tried to advocate for corporate political transparency and accountability. This dissertation examines the antecedents and consequences of primary shareholder activists that seek to improve corporate political transparency in the United States from 2000-2018. Using big data and web-scraping techniques, this dissertation offers several large-scale, novel datasets on U.S. public firms and addresses how shareholder activists select corporate targets, how corporate elites manage shareholder threats, and whether shareholder activists can disrupt corporate financial and political outcomes. Integrating both social movements and organizational theories, this dissertation shows that shareholder activists target corporate political activities not only because of managers not maximizing shareholder value but also due to the co-existence of corporate opportunities and threats that motivate activists promoting liberal causes. Corporate elites’ political ideology serves as a critical component that drives the emergence of shareholder political transparency activism. This dissertation also reveals that corporate elites tend to use multiple tactics such as political disclosure, board oversight, and policy reform to manage the challenges associated with potential or actual shareholder threats. This dissertation also demonstrates that shareholder activism can disrupt corporate political activities, but not financial outcomes.
    • She Works Hard for No Money: Understanding Women's Participation in Multi-Level Marketing Organizations

      Roth, Louise M.; Frederico, Krista Marie; Abramson, Corey; Leahey, Erin E. (The University of Arizona., 2020)
      Over 13 million U.S. women participate in the controversial multi-level marketing (MLM) industry. Advocates claim that the $36 billion industry provides flexible work opportunities for individuals interested in selling reputable consumer products as a licensed distributor within a sales network. Critics, including the U.S. Federal Trade Commission, warn that these companies often have convoluted compensation structures designed to enrich only those at the top of the pyramid-shaped recruitment scheme. With hefty required expenses of overpriced products to maintain an active distributorship, over three-quarters of sellers fail to turn a profit and most report either breaking even or losing money. Given these odds, why do women join an MLM? And why do women stay involved long-term, even if they fail to reach their expected earnings goals? Drawing on participant observation, as well as 59 in-depth interviews with women affiliated with one of three fictionally-named focal MLMs (DermaDynamix, BeautifOil, and Cute Couture), this dissertation illuminates the impressive hard work—and dismaying lack of compensation—for women enrolled as sellers in the highly stigmatized MLM industry. In particular, this study explores the contradictory expectations faced in motherhood: the cultural ideals of “stay-at-home” motherhood, but also the need and desire of many women to generate an income and have career fulfillment, all in a neoliberal context of minimal governmental supports for families (e.g., paid parental leave and low cost child care) and protections against victimization by predatory organizations (e.g., punitive action against deceptive practices by MLMs). To straddle the cultural contradictions within motherhood, these MLM selling women intentionally brought paid work into the home, but then often endeavored to separate their paid work from their household work through various boundary work. For example, rather than work a simultaneous shift, or perform both care work and MLM work at the same time, 76.2% of mothers of young children reported using a temporal boundary of a “sleep shift” to meet their MLM work requirements once children were asleep. This gave them the opportunity to appear to be stay-at-home mothers while still pursuing MLM work, yet this exacted a toll on their sleep and self-care. Using a panel design, consisting of one interview within an average of just over two months since joining an MLM, then a second interview at approximately one year after joining, I found that none of the women reached their expected earnings. Women in the two focal MLMs with a less burdensome investment ($1,500 or less) earned $1.71 per hour, while women with much greater investment requirements of nearly $7,000 earned $10.36 per hour. The high upfront cost in one and the low earnings in the other left all women struggling for any realized earnings beyond their initial investment, leading 44.44% of women to leave the MLM by their second interview. To entice women to remain involved despite both the unmet earnings and unanticipated costs, organizations deployed neoliberal positivity messages, or messages that merge the free-enterprise, low-governmental-regulation emphasis on workers themselves to secure their own employment actualization with the self-help optimism of positive psychology. Women differentially drew upon these same frames in explaining their own behavior within the MLM, with upper-income women more likely to prioritize their personal development and reject responsibility for their failure, and lower-income women more likely to internalize and attribute self-blame to their lack of success. This study concludes that women, especially mothers, are highly interested in reliable and well-paid work-from-home opportunities. As more companies recognize women’s interest in flexible time and work-from-home arrangements, and harness available technologies to offer these options, they will marshal a determined and productive work force—much to their mutual advantage. Further, they may turn the tide away from the alluring, ephemeral promises of the MLM industry, finally delivering a decisive blow to largely unregulated “product-based pyramid schemes” in favor of dependable, well-paid, flexible work.
    • Up Against an (Imaginary) Wall? Economic Insecurity and the White Working-Class in Contemporary America

      Galaskiewicz, Joseph; Kenworthy, Lane; Bjorklund, Eric; Leahey, Erin; Carlson, Jennifer (The University of Arizona., 2020)
      Economic insecurity has grown in the United States since the 1970s. This reflects extensive structural change across key social institutions, like the market, family, and the state. The experience and impact of rising insecurity has fallen disproportionately on the working-class (i.e., those without a four-year college degree). This includes previously insulated members of the working-class, like white non-Hispanics and men. Thus, for much of the white working-class the last fifty years has been a scenario of relative decline. The social, cultural, and economic position of the white working-class—relative to its peers—has generated a potentially distinct set of responses across multiple dimensions. This analysis focuses on two possible ramifications of white working-class economic insecurity: deaths of despair (suicide, drug overdose, alcohol) and reactionary politics. Using a combination of linear modeling and in-depth interviews I assess the relationship between economic insecurity, class position, deaths of despair, and reactionary politics in contemporary America. This research builds up theories of economics and health, class politics, and social inequality. It also provides insight into two highly topical events in modern America: rising deaths of despair and the (re)emergence of white reactionary politics.
    • Remaking Collective Identities: Statistical Statecraft, Indigenous Erasure, and Tribal Citizenship

      Cornell, Stephen; Leahey, Erin; Small-Rodriguez, Desi; Martinez, Daniel E.; Zavisca, Jane (The University of Arizona., 2020)
      In the social sciences, the identification of a population of interest is central to any research, policy, or program. Defining, counting, and classifying populations, however, are not objective. Rather, they are catalyzed by boundary making processes that are deeply embedded in social and political structures. In the United States (US), population classification and enumeration have long served the aims of American statecraft while disenfranchising certain populations. Racial and ethnic minorities, for example, share historical legacies of statecraft determining whose bodies are counted, whose views are official, and which knowledge corpora are privileged. As US demographics shift toward a majority minority population, there is growing need to understand the nature of boundary change, particularly with regard to intraracial heterogeneity and the intersection of citizenship and race. I use the case of American Indians and Alaska Natives (AIANs) to examine how the race-making and nation-making instruments of statecraft control the boundaries of indigeneity and threaten the sustainability of tribal populations. The AIAN case provides broad insight into how the American settler colonial ideology of erasure is reproduced in population statistics and how it can be challenged by marginalized populations who are rapidly becoming the majority in the US. I situate this inquiry within several bodies of literature, including the sociology of race and ethnicity, social stratification, state formation, and critical demography. While prior research on these topics has rarely examined the AIAN population, AIANs are an unusually rich case for analysis due to their concurrent straddling of race, ethnicity, and nationality boundaries. By centering tribal sovereignty, I demonstrate how the ongoing colonial realities of Native nations reflect the dialectical relationship between statecraft and AIAN population statistics. Drawing on an original database of tribal citizenship criteria, US Census data, and a tribal case study, I explore two central research questions. First, how have the data practices of colonial statecraft been utilized to construct and control Indigenous Peoples in the US? Second, how are Native nations reclaiming some measure of control over these data practices to reconstruct their group boundaries? I answer these research questions in three empirical studies that explore the nuances of tribal enumeration and classification. In the first study, I delve into the US Census as the official statistics context to explore how the federal government’s data collection efforts both challenge and support the sovereignty of Native nations. I find the intersection of census self-identification and tribal sovereignty problematic with implications for the utility of official US data on tribal populations. In the second study, I examine the racialization of tribal identity in a cross-national context by analyzing variation in tribal citizenship criteria. Using original data from more than 80 percent of Native nations in the contiguous US, I find that tribal blood quantum persists as a durable boundary of colonial control. In the third study, I focus on the nation state context by partnering with a Native nation to evaluate the extent to which blood quantum policy and demographic realities threaten the sustainability of tribal populations. This final study advances the case for more research in tribal demography to support Indigenous futures. As a whole, this dissertation reveals that the data practices of settler statecraft retain a strong hold on the collective boundaries of AIAN identity and that Native nations have various degrees of control over these boundaries depending on the context. I posit that the colonial imperative of Indigenous erasure is antithetical to the sustainability of tribal peoples and tribal sovereignty. Ultimately, to prevent erasure, Native nations must reclaim their boundaries of belonging.
    • Use of Advanced Microbiological Tools to Assess Surface Waters Used for Produce Production in Arizona Coupled with Innovative Outreach and Education

      Rock, Channah; McLain, Jean; Joe-Gaddy, Valerisa; Gerba, Charles; Cooper, Kerry (The University of Arizona., 2020)
      Background: The need for new pathogen testing methods and for individualized food and water safety curricula are becoming more evident, based on the number of outbreaks in the last decade. Water quality standards are continuously evolving, from shifts in monitoring regulations to increases in approved testing methods, it can be difficult for water professionals to stay abreast of current standards. This dissertation will highlight several primary issues, and will examine possible resolutions, for current concerns related to food and water safety in Arizona, US. Though Arizona is located in the arid Southwestern US, the state is a primary producer of leafy greens and other fresh produce and as such, it is a strong location for the work described herein. Study Aims: The following research and case studies aim to: (1) Establish the utility of a novel indicator organism, Bacteroides sp. to correlate with pathogen presence in agricultural irrigation water samples collected in Southern Arizona; (2) Explore the use of a cutting-edge molecular technology, droplet digital Polymerase Chain Reaction (ddPCR), for accurate analysis of environmental samples, using laboratory experimentation and a review of current literature; and (3) Develop and deliver an innovative food safety and water quality curriculum based on the Food Safety Modernization Act Produce Safety Rule (PSR), that will meet the unique needs of American Indian farmers in Arizona and New Mexico. Methods: Aim (1) focused on comparing concentrations of the currently regulated indicator organism, Escherichia coli (E. coli) to a novel indicator Bacteroides sp. to ascertain whether the novel indicator could overcome some of the known deficiencies related to generic E. coli. Irrigation water samples (n=98) were collected from Southern Arizona farms and analyzed for both indicators at the University of Arizona in Tucson. A comprehensive dataset was collected using several methods, including Real-Time Polymerase Chain Reaction (RT-qPCR), IDEXX Colilert® enzyme substrate technology, bacterial culturing techniques, and field analyses. Data from RT-qPCR (Bacteroides sp.) was compared to Colilert® results (generic E. coli) to evaluate any relationship between the two data sets, while both methods were also compared to bacterial molecular results for pathogen (E. coli O157:H7 and STEC and Salmonella) presence. Aim (2) examined the innovative technology ddPCR using recent published studies across multiple disciplines to evaluate its effectiveness for use in environmental samples on eDNA. Ultimately, a set of considerations were developed for analysis of environmental DNA samples. Lastly, Aim (3) developed a food safety and water quality curriculum based on American Indian cultural narratives using Universal Learning Design methodologies. The curriculum was successfully utilized in three trainings across Arizona and New Mexico for American Indian communities. Qualitative analysis of participant feedback was used to determine the effectiveness of the trainings and key learnings. Results: Aim (1) data suggests that Bacteroides sp., performed equally to generic E. coli in assessing water quality, but not to the extent of proposing Bacteroides sp., as a new indicator. The data did show that generic E. coli is an unsuitable fecal indicator organism, due to an 80.6% false negative rate; furthermore, neither indicator, generic E. coli or Bacteroides sp., correlated with pathogen presence. Thus, the search for other bacteria species for accurate water quality analysis continues. Aim (2) identified areas of environmental research in which ddPCR may be useful, such as marine research. However, the larger dynamic scale of RT-qPCR compared to ddPCR indicates that RT-qPCR would be the preferred method for accurate and reproducible results. Additionally, the cost of ddPCR is greater than RT-qPCR. Lastly, the classes conducted to realize Aim (3) were deemed successful by the surveys conducted and the positive feedback provided by participants. Discussion: The multi-project approach addresses three unique research and extension efforts under the main overarching question: How can water quality evaluation strategies and education in Arizona be improved to aid in the protection of public health? All three aims identified gaps in assessment of food safety and water quality in Arizona. The outstanding false negative rate found using approved methodology for E. coli found in Aim (1) suggests that the current water quality monitoring method is not accurate and this not protective of public health. This finding is supported by recent foodborne outbreaks in the US that may be related to agricultural irrigation water quality. Aim (2) showed that, although ddPCR does provide absolute quantification, the expense of the equipment and reagents as well as the confounding of data due to the complex nature of environmental samples are problematic. Thus, using RT-qPCR in lieu of ddPCR will provide similar, or even improved, results for a fraction of the cost. Aim (3) confirmed, through the development of culturally appropriate materials and deployment of trainings to AI participants, that inclusion of tribal producers though all steps is critical to the development of food safety guidelines that will be useful to all sectors of agricultural producers. By not including tribal produces into the conversation, critical perspectives about agriculture and culture are lost. While this work only touches the surface of the inclusion of tribal growers to the development of governmental regulations, it brings attention to the unique perspectives and traditions that indigenous cultures bring to the conversation.
    • Social Semiotics and Literacy: How Refugee-Background Adult Second Language Learners With Emerging Literacy Make Meaning in Multimodal Assessment Texts

      Warner, Chantelle; Altherr Flores, Jenna Ann; Fielder, Grace; Gilmore, Perry (The University of Arizona., 2020)
      This dissertation contributes to the fields of applied linguistics and literacy studies by considering the complex meaning-making processes of adults from refugee backgrounds as they navigate new textual, linguistic, and educational landscapes. Meaning-making as it is understood here involves both perception and production; it is inherently dialogical, and bound in social semiotic systems, which are not only linguistic but multimodal (Kress, 1994). Making meaning from multimodal texts requires understanding headings, directions, images, graphic devices, top/down and left/right organization, and the relationships among such elements. Taking these complications as a starting point, this research focuses on refugee-background adult second language learners, specifically, those with emerging literacy or who (have) experienced interruptions in their formal, school- based education. Such learners are becoming literate while simultaneously learning the language their literacy is developing in. For these reasons, the texts that are central to their experiences as learners of a new language – particularly language and literacy assessments – are of considerable importance for understanding the intersecting dimensions at play when people learn how to make meaning in a new language. While there is a growing body of research that has examined the psycholinguistic aspects of adult second language learners’ literacy development (e.g., Kurvers, 2002; Tarone et al., 2009; Young-Scholten & Naeb, 2010), many questions remain about the social semiotics of literacy – the interplay of context, culture, history, text, and meaning-making – for adults with emerging literacy or interruptions in their education. Moreover, little research to-date investigates the connections between social semiotics and the visual and multimodal literacies of this population (Altherr Flores, 2017; Bruski, 2012; Whiteside, 2008). This is problematical because many materials designed for beginning second language learners rely heavily on visual cues; without a comprehensive understanding of how such cues are being interpreted, the field’s understanding of how diverse populations make meaning from multimodal texts is compromised. Such knowledge is crucial for designing tests and other materials that aim to support learning. Building on prior scholarship, including an earlier pilot study by the author (Altherr Flores, 2017), this dissertation focuses on the role of visual literacy, language, and lived experience in multimodal texts that are used with adult second language learners with emerging literacy or interrupted education backgrounds. The core data for this research were: 1) English language and English literacy assessments – both in-house assessments used by a local program, and two experimental versions of assessments, created through iterative design as part of the research, 2) textual artifacts, and 3) semi-structured interviews with participants enrolled in community language and literacy classes. The analyses use a critical multimodal social semiotic approach (Kress, 2010; Kress & van Leeuwen, 2006; Pennycook, 2001) to examine the underlying assumptions presented in key texts’ visual and linguistic design, and investigate how this population understands and engages with these multimodal texts. The findings showed assumptions of multimodal design and visual literacy, and assumed content and referential background schemata in the design of the original assessment texts. In particular, the study exposed tensions between participants’ responses to textual and visual prompts and the expectations of test designers. The interview data further revealed the self-articulated strategies participants use to make meaning in multimodal texts, often relying on their lived experiences. By approaching the participants’ meaning-making practices as creative and complex, the research was able to show that the participants often relied on multimodal aspects of the test design that were taken for granted by the test designers. The participants often drew from their lived experiences, and also approached the assessments as a dialogue with the instructor, thus bringing shared frames of reference into play that would potentially be missed by an external evaluator. This study provides insight into how beginning language and literacy learners from refugee backgrounds make meaning from the verbal and visual aspects of assessment materials, and demonstrates how both textual composition and assessment practices may be inadvertently biased against individuals with vastly different literacy experiences. In addition to potentially helping test and materials developers to rethink their design choices, this study expands understandings of what it means to be literate by laying bare the creative and multimodal dimensions of engagement with even the most quotidian types of texts. The study’s results are beneficial for multimodal materials development and assessment practices in learning environments. The results also highlight sociopolitical issues in assessment of this population, and raise questions to be considered concerning assessment in higher stakes environments such as the U.S. naturalization test.
    • Machine Learning and Deep Phenotyping Towards Predictive Analytics and Therapeutic Strategy in Cardiac Surgery

      Konhilas, John P.; Skaria, Rinku; Runyan, Raymond B.; Antin, Parker B.; Langlais, Paul R.; Churko, Jared (The University of Arizona., 2020)
      Introduction: Myocardial infarction (MI) secondary to coronary artery disease (CAD) remains the most common cause of heart failure (HF), costing over $30 billion in healthcare costs. Although early revascularization is the most effective therapy to restore blood flow and salvage myocardium, to date, there are no available treatments to attenuate ischemia-reperfusion injury (IRI). Moreover, post-operative atrial fibrillation (POAF) continues to be a devastating complication following cardiac surgery, affecting 25-40% CABG and 30-40% valve patients. Human placental amniotic (HPA) tissue is known to have anti-inflammatory and wound healing properties and therefore may promote anti-arrhythmic and cardioprotective effects in patients undergoing cardiac surgery. The central hypothesis of this study is the use of predictive modeling in conjunction with HPA application improves cardioprotection against IRI and POAF following cardiac surgery. Methods: We developed predictive models for POAF using machine learning to characterize 340,860 isolated CABG patients from 2014 to 2017 from the national Society of Thoracic Surgeons database. The support-vector machine (SVM) models were assessed based on accuracy, sensitivity, and specificity, and the neural network (NN) model was compared to the currently utilized CHA2DS2-VASc score. Additionally, using a clinically relevant model of IRI, we performed an unbiased, non-hypothesis driven transcriptome and proteome analysis to elucidate cellular and molecular mechanisms of HPA xenograft-induced cardioprotection against IRI. Swine (n=3 in MI only and MI+HPA groups) were subjected to a 45-minute percutaneous IRI protocol followed by HPA placement in the treated group. Cardiac function was assessed, and tissue samples were collected post-operative day 14. Results were further supported by histology, RT-PCR, and Western blot analyses. Lastly, a retrospective study of 78 isolated CABG and 47 isolated valve patients were evaluated to determine if HPA use on the epicardial surface decreases incidence of POAF. Results: Predictive modeling using neural networks demonstrated to outperform the CHA2DS2-VASc score in predicting POAF in CABG patients. Second, we present the first comprehensive transcriptome and proteome profiles of the ischemic, border, and remote myocardium during the proliferative cardiac repair phase with HPA allograft use in swine. Our results establish HPA limited the extent of cardiac injury by 50% and preserved cardiac function. Spatial dynamic responses, as well as coordinated immune and extracellular matrix remodeling to mitigate injury, were among the key findings. Changes in protein secretion, mitochondrial bioenergetics, and inflammatory responses were also noted to contribute to cardioprotection. Third, peri-operative HPA allograft placement has demonstrated a strong reduction in the incidence of POAF following CABG and valve surgery. Discussion: We provide convincing evidence that HPA has beneficial effects on injured myocardium and POAF and can serve as a new therapeutic strategy in cardiac patients. Additionally, we were also able to demonstrate predictive modeling using machine learning holds promise in improving the incidence of POAF in cardiac surgery patients.
    • Racial and Ethnic Disparities Among Minority Geriatric Trauma Patients in the United States: An Analysis of Data From a National Sample Using the Trauma Quality Improvement Program Database

      Gerald, Joe K.; Rosales, Cecilia; Saljuqi, Abdul Tawab Kawa; Gerald, Joe; Joseph, Bellal; Fain, Mindy; Hsu, Paul (The University of Arizona., 2020)
      For this dissertation, I completed three manuscripts with the common overall aim of assessing health disparities among geriatric trauma patients in the U.S. The first manuscript reports on a structured narrative review of the literature comprised of three approaches that ensure comprehensive and targeted research: a scoping review, an exploratory search, and a citation review. The second manuscript is a descriptive analysis of one-year (2016) of data from the American College of Surgeon’s Trauma Quality Improvement Program (ACS-TQIP) with a focus on older adults aged 65 and older who have had an injury. The population was stratified into four groups: Non-Hispanic Whites (NHWs), African Americans, Hispanics, and Other races. For each group, I conducted a simple univariate tabulation for key demographic characteristics and injury-related variables. I also assessed comorbidities, insurance type, and regional differences. Finally, in manuscript three, I performed a one-year analysis of the ACS-TQIP dataset and included all adult trauma patients aged 65 and older who were admitted in 2016. My primary aim was to understand health disparities regarding in-hospital health measures, such as in-hospital mortality, length of stay (LOS), and in-hospital complications. I conducted multivariable regression analysis controlling for age, gender, injury severity, comorbidities, insurance status, calendar year, and type of trauma center. I argue that racial/ethnic disparity exists for GTPs in terms of in-hospital mortality, in-hospital complications, and LOS. Type of injury, severity of injury, and age group are critical predictors of different health outcomes among minority GTPs. Minimizing disparities in GTPs care is crucial to reducing morbidity and mortality. More focused primary research is needed to expand our knowledge of racial/ethnic disparities among GTPs. It is critical that future research stratify each minority group by differences in injury type, injury severity, and age group.
    • Grounding and Rationality

      Cohen, Stewart; Siscoe, Robert Weston; Comesana, Juan; Turner, Jason; Schechter, Joshua (The University of Arizona., 2020)
      Modal metaphysics consumed much of the philosophical discussion at the turn of the century, yielding a number of epistemological insights. Modal analyses were applied within epistemology, yielding sensitivity and safety theories of knowledge as well as counterfactual accounts of the basing relation. The contemporary conversation has now turned to a new metaphysical notion -- grounding -- opening the way to insights by bringing grounding into epistemology. In this dissertation, I attempt to apply insights about grounding within epistemology, opening up a new fruitful exchange between metaphysicians and epistemologists.
    • Environmental Degradation of Aflatoxins and Genetic Diversity of Aspergillus Section Flavi with a Focus on Mozambique

      Orbach, Marc J.; Maxwell, Lourena Arone; Arnold, Anne E.; Bandyopadhyay, Ranajit; Xiong, Zhongguo; Hu, Jiahuai (The University of Arizona., 2020)
      Aflatoxins are potent hepatotoxic, carcinogenic, genotoxic secondary metabolites produced by species in Aspergillus section Flavi that contaminate foods and feeds worldwide. Aflatoxin contamination of staple crops is endemic in Mozambique, and the country has one of the highest rates of liver cancer in the world. Groundnut exportation has been reduced due to contamination above the regulatory limits. However, there are few studies that detail the etiological agents of aflatoxin contamination in Mozambique. In addition, both in developed and developing countries there is a need for sustainable methods to manage crops already contaminated with aflatoxin in the environment of which, the practice of plowing crops under the soil to manage large fields with high levels of aflatoxin has raised concerns about the persistence in the soil of aflatoxins and the aflatoxin-producing fungi of the crop debris. In chapter one, a literature review of aflatoxins, important hosts and taxonomic classification of the major aflatoxin producing fungal groups is presented. Furthermore, the role of the environment, methods of control and management of aflatoxin is discussed. In chapter two, an analysis of fungi of S morphology isolated from maize and groundnuts from the northern region of Mozambique is presented. Fungi of the S morphology generally produce very high levels of aflatoxin and are important causal agents of contamination. A polyphasic approach was taken combining morphological and phylogenetic analysis, comparing the Aspergillus section Flavi fungi of Mozambique with previously described species with similar morphology. This defined the S morphology isolates of Mozambique as members of an A. minisclerotigenes complex. Within the complex, a group of these Mozambique isolates with a 30bp aflR deletion, resulting in an internal 10 amino acid deletion, are potentially important causal agents of aflatoxin contamination of maize and groundnuts. These isolates produce both B and G aflatoxins. These insights provide the basis for understanding the aflatoxin contamination of crops in Mozambique. The findings of this chapter will be submitted for publication in the journal Phytopathology. In chapter three, a new mechanism by which commercial atoxigenic A. flavus biocontrol agents limit aflatoxin levels in crops is presented. We report that these agents are able to degrade up to 82% of the aflatoxins in contaminated maize. Degradation by these isolates was independent of the presence or absence of aflatoxin biosynthesis cluster genes, in contrast to previous data indicating an association of aflatoxin degradation with an isolates’ ability to produce aflatoxin. This insight will provide methods for in crop assessment of degradation and identifies an additional trait for the selection of optimal atoxigenic biocontrol isolates. The results of this chapter has been submitted for publication in the journal Toxins. In chapter four, the persistence in soil of aflatoxins and aflatoxin-producing fungi, following the incorporation of a contaminated crop into the soil is determined. An in vitro analysis suggests that aflatoxins in contaminated crops are significantly degraded and the Aspergillus section Flavi population is reduced when incorporated into the soil via both soil chemical processes and the presence of soil microbes. The observations of this chapter will be submitted as a short communication to the journal Soil Microbiology and Biochemistry. The results of these chapters contribute to insights of etiological agents of contamination of crops in Mozambique and methods to control and manage aflatoxins of contaminated crops to help in the development of rational farming practices that result in improved food safety.
    • Native Spirit: Development, Implementation, and Evaluation of a Culturally-Grounded After-School Program for American Indian Adolescents in an Urban Setting

      Yuan, Nicole P.; Hunter, Amanda Marie; Nuno, Velia L.; Carvajal, Scott C.; Fox, Mary Jo (The University of Arizona., 2020)
      BACKGROUND: Indigenous youth experience disparities in health and education that lead to long-term hardship and poor health. Having a strong sense of cultural identity has been identified as a protective factor for Indigenous youth, although there is a need for empirical studies to further understand the relationship between cultural identity and health. Culturally-based after-school programs (ASPs) provide a valuable service that promotes health and wellbeing for Indigenous adolescents in an accessible setting. OBJECTIVES: The purpose of this dissertation was to investigate the relationship between cultural identity and health among American Indian adolescents. This investigation included the development, implementation, and evaluation of a culturally-grounded ASP located on an urban-based reservation community in Arizona. METHODS: The first stage consisted of a systematic review that identified culturally-based ASPs for Indigenous youth and synthesized evidence on reported health outcomes and outcomes related to intrapersonal constructs. The second stage focused on the formation and implementation of a culturally-grounded ASP, Native Spirit (NS), in partnership with the Boys & Girls Clubs of Greater Scottsdale (BGC) and the Salt River Pima-Maricopa Indian Community (SRPMIC). The third stage used a mixed methods approach to evaluate the impact of participation in the NS program on cultural identity, self-esteem, and resilience in American Indian (AI) adolescents (grades 7-12). RESULTS: The systematic review identified 9 articles representing 9 different ASPs that met the inclusion criteria and then were critiqued. Primary outcomes included substance abuse, cultural identity, and intrapersonal constructs including self-efficacy, self-concept, and self-esteem. The NS partnership, described in stage two, resulted in the development of a 13-session culturally-grounded ASP that focuses on local cultural values and practices. Each session is facilitated by 1-2 local cultural practitioners and community leaders. The stage three evaluation showed increases in mean strength in cultural identity, resilience and self-esteem between baseline and posttest evaluation. Themes related to benefits of participating in the program included curiosity and commitment to cultural identity, increases in confidence and self-esteem, and ability to overcome challenges and build resilience. CONCLUSIONS: The current study provided additional evidence of the positive impact that strength in cultural identity imparts on the health and wellbeing of AI adolescents. These findings also highlighted unique opportunities for health promotion with collaborations with BGCs and after-school programs.
    • Quantitative Exploration of Nurses’ Task-Technology Fit within the Electronic Health Record Using Regression and Data Mining: An Ehr Workflow Analysis

      Gephart, Sheila M.; Tolentino, Dante Anthony; Insel, Kathleen; Carrington, Jane; Subbian, Vignesh (The University of Arizona., 2020)
      BACKGROUND: As we continue to progress with the use of Electronic Health Records (EHR), there is a need to improve nurses’ user experience (UX). An understanding of nurses’ task-technology fit (TTF) with EHR performance and an examination of nurses’ navigational behaviors within the EHR is warranted. PURPOSE: To quantify nurses’ TTF and describe their navigational patterns in the EHR to provide pragmatic solutions to improving nurses’ UX with the EHR. METHODS: Using a cross-sectional quantitative design, the first phase of the study examined the relationship between individual, task, and technology characteristics to subjective workload, EHR efficiency, and composite performance. The second phase of the study used computational ethnography using EHR audit logs as an in-situ data source. Sequential Pattern Mining (SPM) and Markov chain Analysis (MCA) were used to examine the audit logs. RESULTS: In a sample size of 95 nurses, 50% were white, 84% were females, 83% considered themselves as EHR proficient, and 34% worked in a Medical/Surgical unit. The first phase of the study revealed age and nursing experience were negatively correlated to ease of use/training, workload, and efficiency. Regression analysis also showed that the relationship with informatics staff was a strong predictor of nurses’ EHR workload. The second phase of the study was from a random sample size of 20 nurses from the Phase I participant pool. “Documentation” was the most frequent EHR event that was used by nurses accounting for 28% of their EHR time. SPM revealed that “query clinician” – “documentation” was the most frequent sequential pattern. In reviewing the transition probability matrix, nurses were most likely to navigate launching an application after logging in. Two different models were presented, showing the primary and secondary navigational pathways that nurses would traverse when using the EHR. CONCLUSION: The study identified the different TTF characteristics that may impact nurses’ performance within the EHR. Healthcare organizations need to deliver a good TTF to attain an effortless UX. Unmasking time-based navigation behavior of nurses using computational ethnography can assist in the redesign of EHR screens to the right nurse, at the right time, and in the right sequence.
    • The Iranian Perception of Europe During the Early Decades of the Nineteenth Century

      Talattof, Kamran; Ebrahimian, Mojtaba; Noorani, Yaseen; Betteridge, Anne; Raval, Suresh (The University of Arizona., 2020)
      Up until the turn of the nineteenth century, the Iranian knowledge of Europe was very limited. Iranians considered Western Europe with the generic term, “Farangistan,” equated Farangistan with the lands of Christendom, regarded Russians as uncouth people of Asia, and harbored stereotypical images of Europeans for centuries. However, with the intensification of European presence in Asia, mainly due to the colonial rivalries of France, England, and Russia, Iranians began to pay renewed and earnest attention to European countries. The present dissertation, "The Iranian Perception of Europe during the Early Decades of the Nineteenth Century" examines the nature of the Iranians' “discovery” of Europe during the early nineteenth century. By close analysis of five prominent early-nineteenth-century Persian travelogues of Europe, it demonstrates that even as the Iranians assumed and accepted the superiority of European military technology, mode of government, and educational system, they did not have a favorable approach to European gender relations and religious practices when they intensified their attention to Europe. Thus, it argues that, during the early nineteenth century, the Iranian perception of Europe was pragmatic yet ambivalent, and that this ambivalence can explain why the Iranian court did not endorse full-scale European-style military, administrative, political, and educational reforms in this period.
    • Social Context Differences in Activation of Synaptic Plasticity Pathways in Birdsong

      Miller, Julie E.; So, Lisa Yong; Fuglevand, Andrew; Rance, Naomi; Falk, Torsten (The University of Arizona., 2020)
      Vocal communication is critical for survival and is used by humans and animals for many reasons including socialization, and the inability to communicate is detrimental to one’s life. The neural mechanisms underlying vocal communication are poorly understood leading to poor therapeutic options when a dysfunction arises. In humans, Kuhl hypothesized that social interactions enhance the ability to learn speech and language (Kuhl, 2007). The circuitry that encodes for social behavior may gate the acquisition of speech making it important to understand social behaviors and the underlying mechanisms. Songbirds have been used as a model system to gain insight into the central brain mechanisms of vocal communication, particularly the study of behavior in different social contexts. In chapter two, I focused on the role of dopamine (DA) in social context-dependent differences in song. DA is an important neuromodulator of motor control across species. In zebra finches, DA levels vary in song nucleus Area X depending upon social context. DA levels are high and song output is less variable when a male finch sings to a female (female directed, FD) compared to when he is singing by himself (undirected, UD). DA modulates glutamatergic input onto cortico-striatal synapses in Area X via N-methyl-D-aspartate (NMDA) and DA receptor mechanisms, but the relationship to UD vs. FD song output is unclear. I investigated the expression of molecular markers of dopaminergic and glutamatergic synaptic transmission (tyrosine hydroxylase – TH, alpha-synuclein – α-syn) and plasticity (NMDAR2B – GRIN2B) following singing (UD vs. FD) and non-singing states to understand the molecular mechanisms driving differences in song output. With higher UD song amount, there were increases in TH, α-syn, and NMDAR2B protein levels. By contrast, the amount of FD song did not have a relationship with TH and NMDAR2B expression. Levels of α-syn showed differential expression patterns based on UD vs. FD song, consistent with its role in modulating synaptic transmission. I proposed a molecular pathway model to explain how social context and amount of song are important factors for molecular changes required for synaptic transmission and plasticity. In chapter three, I honed in on synaptic plasticity molecular pathways as mediators of social context differences in song output. Based on chapter two results, NMDARs were strong targets suggesting the role of synaptic plasticity in social context differences. In addition, a secondary synaptic plasticity pathway involving brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) was chosen since a rise in BDNF levels in a cortical song nucleus increased song learning. Therefore, I identified four molecules downstream of NMDAR and TrkB activation and determined their expression in Area X after UD and FD song: calcium/calmodulin dependent protein kinase II beta (CaMKIIB), homer scaffold protein 1 (HOMER1), serine/threonine protein kinase (Akt), and mechanistic target of rapamycin kinase (mTOR). My hypothesis was that all four protein levels would increase with more UD song in line with the more variable UD song and decrease with more FD song. My findings show that strong relationships between social context-dependent singing and protein levels for these key molecules do occur although not all results are in line with my hypothesis. As predicted, HOMER1 protein levels increased with the amount of UD song but decreased with the amount of FD song. Protein levels of mTOR decreased with the amount of FD song but showed no change with UD singing, the latter finding contradicting my hypothesis that mTOR levels would increase with UD singing. CaMKIIB protein levels fluctuated depending on the time spent singing UD song, and Akt protein levels trended downward with more time spent singing UD song. Both molecules showed no change with FD song. Therefore, my results support involvement of the synaptic plasticity pathways, but it may not be as straightforward as up and down regulation but suggests more complexity. In chapter four, I probe at the significance of the results from chapters two and three as well as address potential future directions based on my findings.
    • A Multigenerational Investigation of Voice Onset Time in English-Hebrew Heritage Speakers

      Farwaneh, Samira; Jones, Kyle Stewart; Hudson, Leila; Azaz, Mahmoud; Ussishkin, Adam (The University of Arizona., 2020)
      This study investigates the speech acoustics of two generations of U.S. olim (immigrants) in Israel, first generation immigrants, whose first language (L1) is American English (AE), and their second-generation children, for whom English is a heritage language (HL), as well as L1 Modern Hebrew (MH) speakers. A specific HL accent has been demonstrated in the studies that have investigated the phenomenon, showing that heritage speakers have good control of phonetic/phonological contrasts between their two languages but demonstrate distinct patterns from both native speakers (NS) and second language (L2) learners (who both show L1 influence) (Godson 2004; Chang et al. 2009, 2011; Kupisch et al. 2014; Lein et al. 2016). The research focuses on issues of heritage language phonology and intergenerational multilingualism: What is the speech of HL speakers of AE in Israel like? How does this speech compare to the speech of their parents (their main source of input for AE)? How does MH, their L2 or primary language, respectively, affect their AE? These questions are investigated through a language questionnaire and a picture naming task targeting voice onset time (VOT) in the AE and MH stops /bdg ptk/, which differ in how phonological voicing/voicelessness is cued phonetically by VOT: AE voiced stops /bdg/ have short lag VOT (< 40 ms), while voiceless stops /ptk/ have long lag VOT (> 40 ms) (Lisker and Abramson 1964). In MH, voiced stops /bdg/ exhibit prevoicing (sometimes up to -100 ms or more), while /pt/ have short lag VOT (< 40 ms) and /k/ exhibits long lag VOT (often greater than 60 ms) (Laufer 1998). A total of 7 HS of AE; 10 American olim (immigrants; native speakers of AE); and 5 NS of MH participated in the experiment. Acoustic analysis demonstrates that HL speakers, echoing previous studies, have excellent control over phonetic and phonological contrasts in salient distinctions between their two languages, despite greater overall variability. VOT is within MH norms when speaking MH and within AE norms when speaking AE, results in line with Flege (1995)’s Speech Learning Model (SLM), which predicts that the younger the age of acquisition, the better phonetic discernment between the two languages will be, resulting in the formation of distinct phonetic categories for both languages. The American olim, rather than exhibiting purely L1 influence on the L2, show some L2 (MH) influence on the L1 (AE): Voiced stops, even in AE, tend to be produced as prevoiced, rather than short lag, a shift phenomenon that has been documented for other languages (Pavlenko 2000). This is especially apparent for /b/, but some speakers produce /dg/ with prevoicing as well. Language questionnaires taken by olim participants suggest that this L2 influence is the result of both extensive use of the L2 and cultural identification with their fellow Israeli Jews. NS of MH demonstrate typical L1 MH influence on their AE, but produce native-like AE values for voiceless stops /ptk/, likely because MH has long lag for /k/.
    • Understanding Atmosphere-Ocean-Land-Ice Interactions in the Earth System

      Zeng, Xubin; Reeves Eyre, James Edward Jack; Behrangi, Ali; Castro, Christopher L.; Russell, Joellen L. (The University of Arizona., 2020)
      As numerical models of the Earth system become more sophisticated – in terms of number of component models and the complexity of physical processes simulated – it becomes more difficult to understand their biases. This is especially true for near-surface quantities such as 2-meter temperature and wind speed that are influenced by interface processes. This dissertation consists of four studies that address this difficult problem. All span multiple components of the Earth system and are global in scope, making use of global observational data sets and Earth system models (ESMs). Earth system models parameterize ocean surface fluxes of heat, moisture and momentum with empirical bulk flux algorithms, which introduce biases and uncertainties into simulations. We compare, for the first time, the effects of three different algorithms in both atmosphere and ocean model simulations using E3SM. Flux differences between algorithms are larger in atmosphere simulations (where wind speeds can vary) than ocean simulations (where wind speeds are fixed by forcing data). Surface flux changes lead to global scale changes in the energy and water cycles, notably including ocean heat uptake and global mean precipitation rates. Compared to the control algorithm, both the Coupled Ocean-Atmosphere Response Experiment (COARE) and University of Arizona (UA) algorithms reduce global mean precipitation and top of atmosphere radiative biases. Ocean barrier layers (BLs) separate the mixed layer from the top of the thermocline and are able to insulate the mixed layer from entrainment of cold thermocline water. Here, we provide the first global BL assessment in three ESMs. Compared to observations, models reproduce the global distributions as semipermanent features in some tropical regions and seasonal features elsewhere. However, model BLs are generally too thin in tropical regions and too thick in higher latitudes. BL thickness biases are related to atmosphere biases in the tropics, but at higher latitudes biases are dominated by ocean circulation errors. Global and regional water cycle is a crucial component of the Earth system, and numerous studies have addressed the individual components (e.g., precipitation). Here we assess, for the first time, if remote sensing and reanalysis data sets can accurately and self consistently portray the Amazon water cycle. This is further assisted with satellite ocean salinity measurements near the mouth of the Amazon River. Ensemble means, which are widely used for individual components, are found to produce large biases in water cycle closure. Closure is achieved with only a small subset of data combinations, which rules out the lower precipitation and higher evaporation estimates. The common approach of using the Obidos stream gauge (located hundreds of kilometres from the river mouth) to represent the entire Amazon discharge is found to misrepresent the seasonal cycle, and this can affect the apparent influence of Amazon discharge on tropical Atlantic salinity. Near-surface air temperature (SAT) over Greenland has important effects on mass balance of the ice sheet. Here, extensive in situ SAT measurements (~1400 station-years) are used to assess monthly mean SAT from sixteen global and regional products. Ice sheet-average annual mean SAT from different data sets are highly correlated in recent decades, but their long term means and trends differ enough to affect results of ESM evaluations. Compared with the best observational estimate, thirty-one ESM historical runs from the CMIP5 archive reach ~5 degrees Celsius for 1901–2000 average bias and have opposite trends for a number of sub-periods. In the course of the above studies, my other research contributions have included model development and evaluation activities for the DOE E3SM Coupled Model Version 1, analysis of subtropical cloud errors in the E3SMv1 Atmosphere Model, and analysis of Greenland ice sheet surface interface processes in the Regional Arctic System Model.
    • Comprehensibility of Game Rulebooks: Perspectives from a Community of Practice

      Short, Kathy G.; Niecikowski, David Matthew; Gilmore, Perry; Jaeger, Elizabeth L. (The University of Arizona., 2020)
      This qualitative study was contextually framed within a community of practice consisting of the traditional board and card game community members. The findings were developed through constructivist grounded theory and Delphi survey methodology in response to these two research questions: (1) As a community of practice made-up of traditional game players and professionals, what are their recommendations on comprehensible rulebook features to meet readers’ needs? (2) In what ways do published rulebooks reflect these identified rulebook comprehensibility features? The dissertation’s salient finding is the Comprehensible Features of Rulebooks Performance List co-constructed by members in the traditional gaming community of practice made-up of 21 solicited surveyed industry experts and informed by unsolicited public forum comments by 541 users on the website Boardgamegeek. The evaluation results of eight published rulebooks are discussed using the performance list’s 92 weighted features organized into 10 categories. Additional findings were developed from the performance list that include: Interdependence of Referencing to Support Readers’ Memory, Power Features, and Predicting Intended Audience Satisfaction with Rulebook Comprehensibility Score. The findings have immediate implications for evaluating the comprehensibility of game rulebooks and guide possible rulebook revisions and/or the creation of supplemental reader supports. These findings can also inform future research on designing comprehensible rulebooks and observing readers’ actions with rulebooks modified by the performance list to meet readers’ needs. Broader implications include employing this study’s synthesized contextual framework and research methodology to develop a solution to a community of practice’s shared concern.
    • We're All Americans Now: How Mexican American Identity, Culture, and Gender Forged Civil Rights in World War II and Beyond

      Morrissey, Katherine G.; Steptoe, Tyina; Key, Lora Michelle; Perez, Erika; Hemphill, Katie (The University of Arizona., 2020)
      “We’re All Americans Now: How Mexican American Identity, Culture, and Gender Forged Civil Rights in World War II and Beyond,” argues that World War II was a pivotal moment in the history of race formation and civil rights activism in the Southwest. This dissertation focuses on middle-class Mexican Americans in three Southwest-border cities: Los Angeles, Tucson, and El Paso and how they used wartime necessities to insert themselves into local and national politics to advocate for themselves and all Mexican Americans. These three Southwest cities provide an important case study that highlights class, gender, and race, showing the relationships between middle-class and working-class Mexican Americans, as well as their relationships with Anglos during the war. This project centers on Tucson, with its distinct construction of a historically powerful middle class, while the comparisons to El Paso and Los Angeles highlight the structural and philosophical differences that existed in Mexican-American communities across the Southwest. Divergences of segregation and discrimination in these three cities shaped Mexican Americans’ racial subjectivities and their activism during the war. Middle-class Mexican Americans used their claims to racial whiteness to establish relationships with city and state officials in order to advocate for working-class Mexican Americans. Within that representation, however, the middle class often had to defend Mexican-Americans’ relationship with Mexico and demonstrate their patriotism. Mexican-Americans’ wartime activism led directly to grassroots civil rights programs and agendas that centered squarely on each community’s needs and constraints. As a regionally centered study, this works redefines civil rights activism and the larger understandings of the Mexican-American experience.
    • The Fate of Nitroaromatic Contaminants in Anaerobic Environments: Formation of Coupling Products between Reduced Nitroaromatic Intermediates and Covalent Bonding of Aromatic Amines to Humus Model Compounds

      Sierra-Alvarez, Maria Reyes; Field, James A.; Kadoya, Warren; Farrell, James; Mash, Eugene A.; Abrell, Leif M. (The University of Arizona., 2020)
      Nitroaromatic compounds are a class of toxic, synthetic chemicals used in a variety of industries, including explosives, pharmaceuticals, and pesticides. They may enter the environment through wastewater discharge or deposition onto soil surfaces, i.e. on firing ranges. Rainwater can dissolve nitroaromatics and transport them into the subsurface, where they may encounter anaerobic conditions. There, soil microbes and/or reduced minerals may catalyze the reduction of nitroaromatics to aromatic amines via three, two-electron transfers per nitro group. This study builds on previous work on the fate of 2,4-dinitroanisole (DNAN), an insensitive munitions compound that is replacing trinitrotoluene (TNT) in explosives formulations to reduce the risk of accidental detonations. It was found that DNAN formed azo dimers and trimers, which can be more toxic than nitroaromatic compounds, when incubated in anaerobic sludge and soil. Furthermore, 14C-radiolabeled DNAN became immobilized to the insoluble fraction of soil organic matter (humus) in soil incubations, which was enhanced under reducing conditions. This could be used as a strategy to “remove” nitroaromatics from the subsurface environment. The objective of this work is to understand the mechanisms that caused DNAN to form azo compounds and become incorporated into humus in anaerobic incubations. The hypothesis was that once DNAN became reduced biologically (catalyzed by microbes), abiotic nucleophilic substitution reactions occurred, either between reduced intermediates of DNAN to form azo compounds or between humic moieties, such as quinones, and DNAN-derived aromatic amines to form “bound residues.” These reactions were originally thought to take place only under aerobic conditions, with aromatic amines forming free radical species. We conducted biological incubations of 4-nitroanisole in anaerobic granular sludge and chemical pairing experiments between reduced 4-nitroanisole intermediates, 4-nitrosoanisole and 4-aminoanisole, and between aromatic amines, including those resulting from DNAN reduction, and model quinone compounds. Using ultra-high performance liquid chromatography, UV-Vis spectroscopy, and mass spectrometry, we studied reactant disappearance and product formation. In anaerobic sludge incubations of 4-nitroanisole, azo dimer 4,4ʹ-dimethoxyazobenzene formed but was subsequently reductively cleaved. Hypothesizing that the formation of this azo dimer was due to the chemical coupling of 4-nitroanisole reduced intermediates 4-nitrosoanisole and 4-aminoanisole, we incubated these compounds in abiotic, anoxic conditions. Although 4,4ʹ-dimethoxyazobenzene formed, the major product was 4-methoxy-4ʹ-nitrosodiphenylamine, another coupling product. We studied the toxicity of these two products to Aliivibrio fischeri and found that they were orders of magnitude more toxic than reactants 4-nitrosoanisole and 4-aminoanisole. In studies chemically pairing aromatic amines, which would result from nitroaromatic reduction, with quinone compounds that model humus, we detected the formation and accumulation of covalently-bonded Michael adducts and imines resulting from nucleophilic addition pathways. These results provide insight into the mechanisms through which DNAN molecules both bind to each other and to quinone moieties present in humus as they are sequentially reduced to aromatic amines. To prevent the accumulation of toxic coupling products and enhance immobilization to humus on sites contaminated with nitroaromatics, anaerobic conditions should be created, along with the addition of electron donor and organic carbon amendments to promote reducing conditions, which both cleave coupling products and generate aromatic amines, and increase humus content, respectively.