• Defect quantification in metal halide perovskites: the solid-state electrochemical alternative

  De Keersmaecker, Michel; Armstrong, Neal R.; Ratcliff, Erin L.; Department of Chemical and Environmental Engineering, The University of Arizona; Department of Chemistry and Biochemistry, The University of Arizona; Department of Materials Science and Engineering, The University of Arizona (Royal Society of Chemistry, 2021-07-24)

  Electrochemical methodologies are routinely used to determine energetics and defect density in semiconductor materials under operando conditions. For metal halide perovskites, electrochemical methods are restricted to a limited group of non-solvent electrolytes. This challenge is circumvented via a ”peel and stick” solid electrolyte that can contain redox active species, is transparent to visible and X-ray photons for simultaneous characterizations, and can be removed for quantification of near-surface composition and energetics using photoelectron spectroscopies. Defects are qualified for both near-stoichiometric and over-stoichiometric MAPbI3 films using controlled hole and electron injection, afforded through potential modulation with respect to a calibrated internal reference. Inclusion of mid-gap redox probes (ferrocene) allows for probing density of states, whereby electron transfer reversibility is shown to be dependent upon the number of ionized defects at the perovskite's band edges. A detailed Coulombic analysis is provided for determination of defect energetics and densities, with a near-stoichiometric film exhibiting a defect density of ∼2 × 1017 cm−3 at 0.1 eV above the valence band. We predict that this easily implemented three-electrode platform will be translatable to operando characterization of a range of semiconductor materials, including thin film perovskites, (in)organic semiconductors, quantum dots, and device stacks, where the removable solid electrolyte functions as the “top contact”.
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  The Wikipedia Global Consciousness Index: A Measurement of the Awareness and Meaning of the World-as-a-Whole

  Mitchneck, Beth; Jones, J.P.; Stieve, Thomas; Ortiz, David; Surdeanu, Mihai (The University of Arizona., 2021)

  To supplement current globalization indexes, I propose a new index, the Wikipedia Global Consciousness Index (WikiGCI). Available indexes that measure globalization rely on network definitions for their theoretical frameworks and count objects crossing borders. The WikiGCI, defined as a measure of awareness and meaning of the world-as-a-whole, is founded on Robertson’s (1992, 2009, 2011) suggestion of global consciousness. The first research objective is to construct the new index as an empirical assessment of global consciousness by applying the top 100 global articles as the empirical units. Global articles are the Wikipedia articles edited in the most countries, identified by geolocating the IP address edits. Furthermore, I discursively analyze how these Wikipedia articles express global consciousness by statements of global wholeness in their narratives. I also apply Steger and James’ (2013, 2019) analysis of global social meaning to the global articles to identify how editors express ideology, imaginaries, and categories of the being-in-the-world. The second research objective is to discursively analyze regional patterns in Wikipedia’s global and local articles. I performed a mixed method, multilingual discursive analysis to examine how four globalizing discourses (references to the countries in the world’s economic core, the use of English in citations, references to international media institutions, and the monetization of commodities) can distinguish place representations between two groups of articles. One group of articles edited only in Peru, Russia and the U.S. were local articles with local representations. The other group consisted of the global articles edited in those three countries as well as the rest of the world that contained the widest, shared representation of the world. This discourse analysis reveals that the representation of the world is not strictly determined by the core. While the socio-economic power in the core creates the globalizing discourses, non-core editors engage with the discourses to depict the world based on the socio-historic conditions of their countries.
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  College, Chronic Illness, and COVID-19: It’s Complicated

  Rhoades, Gary; Mohr, Whitney C.; Kraus, Amanda; Lee, Jenny (The University of Arizona., 2021)

  This dissertation explores literature related to disability, university communication, andinequality regimes to understand the conceptualization of the ideal college student and how COVID-19 disrupted and enforced the systemic ideals of who belongs at and in the rhetoric of institutions of higher education. This study investigated how university leadership, public briefings, and email communication during the COVID-19 era were (or were not) inclusive of students with chronic illness and/or immunodeficiencies. A qualitative case study and qualitative methodologies were used to explore the communication of one university to and about the chronically ill population for 1 year as it reacted and responded to the Coronavirus (COVID-19) pandemic. My analysis found that university leadership communicated in a way that excluded students with chronic illness from the college experience, and when this population was included, the rhetoric was problematic, blaming, and shaming. University communications, media, and marketing are focused on the “ideal” college student and the “ideal” college experience. Higher education institutions need to reconceptualize their perception of who and what is ideal. Inclusive communications and marketing are key in reflecting the college’s commitment to the chronically ill. It was through this dissertation, the related research and recommendations, and my own lived experiences that I began to reconceptualize the idea of being immunocompromised in college and begin to understand it as being immunocomplicated.
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  Re-membering Jalal Al-E Ahmad and His Intimate Circle: The Possibility of Rupture and Reinforcement in the Hegemonic Masculinity of the Pahlavi Era

  Darling, Linda; Ghoreishian, Ana; Darling, Linda; Ortiz, David; Pieper Mooney, Jadwiga; Talattof, Kamran (The University of Arizona., 2021)

  My research examines the impacts of Jalal Al-e Ahmad, Simin Daneshvar and a selection of theirintimate intellectual circle on the hegemonic masculinity of their era as it approached the “unthinkable” Iranian Revolution of 1979. Given that Al-e Ahmad became so profoundly influential as it relates to the emergence of the post-revolutionary Perso-Islamic identity, my dissertation focuses primarily on Al-e Ahmad’s life, letters and literary work. More specifically, I am interested in examining the gender practices among this selection of Pahlavi-era Iranian intellectuals in their personal lives and their literary works. Since the reconfiguration of gender practice is influenced by multiple actors in both state and civil society, my analysis utilizes a Gramscian framework of cultural change which carefully explores the significant role that intellectuals can play in the continuous renegotiations of gender practices. After establishing a working structure of Iranian hegemonic masculinity in the Pahlavi Era, Ioffer six areas of inquiry. Chapter 1 gives a brief overview of the 19th-20th century intellectuals in modern Iran and locates Al-e Ahmad in that context. Chapter 2 establishes the framework for hegemonic masculinity during the Pahlavi Era by examining the driving forces of Iran’s reconfigurations of hegemonic masculinity including the state and religious patriarchy as well as the Iranian women’s rights movement. Chapter 3 focuses on how Al-e Ahmad's relationship to Daneshvar challenged and reinforced hegemonic masculinity. Chapter 4 explores a selection of Al-e Ahmad’s short stories in the context of violence and injustice under religious and state patriarchy. Chapter 5 delves into Al-e Ahmad’s Westoxification as it relates to hegemonic masculinity and silence. Chapter 6 examines Al-e Ahmad, sex, sexuality and gendered renegotiations in the context of religiosity, secularism, and the unfulfilled rupture of sexual taboos. This research concludes by noting that while Al-e Ahmad and his intimate circle reinforced hegemonic masculinity, if we are to look at gendered performativity as something that needs repeated performance, these disruptions - however unintentional or fleeting - bring us one step closer toward a sustainable rupture of hegemonic masculinities.
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  Maturing Engineered Heart Tissues for Titin-Based Disease Modeling

  Granzier, Hendrikus L.; Keschrumrus, Vic P.; Tardiff, Jil C.; Konhilas, John P.; Colson, Brett A. (The University of Arizona., 2021)

  Engineered heart tissues (EHTs) are three-dimensional, fibrin-based heart muscle constructs developed as an advanced disease modeling tool for therapeutic development and personalized medicine, but at a fraction of the time and cost of traditional animal models. EHT maturity can be evaluated by identifying the isoforms of titin, a giant filamentous protein that regulates sarcomere organization and provides passive stiffness to cardiomyocytes, and has been implicated in cardiomyopathies. For example, dilated cardiomyopathy (DCM) patients have been shown to undergo eccentric remodeling with a switch from a stiffer N2B isoform to a more compliant N2BA isoform. Current neonatal rat EHTs express immature titin isoform expression patterns and require additional maturation to improve clinical relevancy. This dissertation examines different approaches to maturing titin isoform expression in EHTs using angiotensin II and triiodothyronine supplementation, chronic electrical stimulation, and extracellular matrix (ECM) modifications. Angiotensin II supplementation at 20 µM significantly increased mature N2B titin isoform expression while triiodothyronine supplementation had no significant effect. Chronic electrical stimulation at 0.5 Hz significantly enhanced the force production, fractional shortening, and contraction velocity in EHTs. However, paced EHTs exhibited a negative force-frequency relationship indicating other factors like calcium handling should also be considered for maturation. Surprisingly only N2BA titin isoform expression was significantly increased in paced EHTs. Sarcomere width and ECM, myofiber, mitochondria, and void fractional area were also significantly increase in paced EHTs while significant reduction was observed in Z-disk width, sarcomere length, collagen fibril width, and cytoplasm, cardiomyocyte, and empty fractional area. Decreasing the fibrinogen concentration lowered the Young’s Modulus of the initial fibrin gel used for generating EHTs. This change in extracellular matrix stiffness enhanced contraction kinetics during development and significantly increased the mature N2B titin isoform expression. Finally, EHTs generated from human induced pluripotent stem cells differentiated into cardiomyocytes were examined for maturity level. Contraction kinetics reveal significantly lower values in comparison to neonatal rat EHTs and only fetal cardiac titin isoform was detected in titin analysis. Overall, these findings have only scratched the surface of the intricate overlap of biological, mechanical, and electrical cues necessary to fully mature EHTs.

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