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Autism Spectrum Disorder (ASD) is a lifelong neurodevelopmental disorder that is becoming increasingly common. Autism does not yet have a known etiology, nor a definitive diagnostic test, thus making diagnosis a difficult and rarely uniform task. Currently, ASD is behaviorally diagnosed based on criteria defined by the American Psychiatric Association

Autism Spectrum Disorder (ASD) is a lifelong neurodevelopmental disorder that is becoming increasingly common. Autism does not yet have a known etiology, nor a definitive diagnostic test, thus making diagnosis a difficult and rarely uniform task. Currently, ASD is behaviorally diagnosed based on criteria defined by the American Psychiatric Association in the Diagnostic and Statistical Manual of Mental Disorders (DSM). Recently, a change was made in the criteria from more lenient criteria in DSM-IV-TR, to more narrow criteria laid out by the DSM-V, which supersedes the DSM-IV-TR. This drastic change raised many questions and debates about which set of criteria are better. The more lenient criteria offers a more inclusive diagnosis giving greater access to therapies; while the narrow diagnostic criteria excludes some individuals, creating a more uniform diagnosis that's easier to use in research. This thesis analyzes the change in diagnostic criteria from the DSM-IV-TR to the DSM-V and the effects of these changes on the practices of diagnosis. In addition, it explores the implications of this change for the families of children with autism and for those involved in autism research, examining their respective opinions and interests pertaining to narrow verses broad diagnostic criteria. Building on this analysis, the thesis offers recommendations about diagnostic criteria should be set. It argues that the wellbeing of patients takes priority over the interests of researchers, and thus diagnosis should be done in a way that offers the best prognosis for all children who suffer from autistic symptoms.
ContributorsBremer, Michelle Nichole (Author) / Hurlbut, Ben (Thesis director) / Robert, Jason (Committee member) / Brian, Jennifer (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
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Lithium ion batteries are quintessential components of modern life. They are used to power smart devices — phones, tablets, laptops, and are rapidly becoming major elements in the automotive industry. Demand projections for lithium are skyrocketing with production struggling to keep up pace. This drive is due mostly to the

Lithium ion batteries are quintessential components of modern life. They are used to power smart devices — phones, tablets, laptops, and are rapidly becoming major elements in the automotive industry. Demand projections for lithium are skyrocketing with production struggling to keep up pace. This drive is due mostly to the rapid adoption of electric vehicles; sales of electric vehicles in 2020 are more than double what they were only a year prior. With such staggering growth it is important to understand how lithium is sourced and what that means for the environment. Will production even be capable of meeting the demand as more industries make use of this valuable element? How will the environmental impact of lithium affect growth? This thesis attempts to answer these questions as the world looks to a decade of rapid growth for lithium ion batteries.

ContributorsMelton, John (Author) / Brian, Jennifer (Thesis director) / Karwat, Darshawn (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Lithium conducting garnets in the family of Li7La3Zr2O12 (LLZO) are promising lithium conductors for solid-state batteries, due to their high ionic conductivity, thermal stability, and electrochemical stability with metallic lithium. Despite these advantages, LLZO requires a large energy input to synthesize and process. Generally, LLZO is synthesized using solid-state reaction

Lithium conducting garnets in the family of Li7La3Zr2O12 (LLZO) are promising lithium conductors for solid-state batteries, due to their high ionic conductivity, thermal stability, and electrochemical stability with metallic lithium. Despite these advantages, LLZO requires a large energy input to synthesize and process. Generally, LLZO is synthesized using solid-state reaction (SSR) from oxide precursors, requiring high reaction temperatures (900-1000 °C) and producing powder with large particle sizes, necessitating high energy milling to improve sinterability. In this dissertation, two classes of advanced synthesis methods – sol-gel polymer-combustion and molten salt synthesis (MSS) – are employed to obtain LLZO submicron powders at lower temperatures. In the first case, nanopowders of LLZO are obtained in a few hours at 700 °C via a novel polymer combustion process, which can be sintered to dense electrolytes possessing ionic conductivity up to 0.67 mS cm-1 at room temperature. However, the limited throughput of this combustion process motivated the use of molten salt synthesis, wherein a salt mixture is used as a high temperature solvent, allowing faster interdiffusion of atomic species than solid-state reactions. A eutectic mixture of LiCl-KCl allows formation of submicrometer undoped, Al-doped, Ga-doped, and Ta-doped LLZO at 900 °C in 4 h, with total ionic conductivities between 0.23-0.46 mS cm-1. By using a highly basic molten salt medium, Ta-doped LLZO (LLZTO) can be obtained at temperatures as low as 550 °C, with an ionic conductivity of 0.61 mS cm-1. The formation temperature can be further reduced by using Ta-doped, La-excess pyrochlore-type lanthanum zirconate (La2Zr2O7, LZO) as a quasi-single-source precursor, which convert to LLZTO as low as 400 °C upon addition of a Li-source. Further, doped pyrochlores can be blended with a Li-source and directly sintered to a relative density up to 94.7% with high conductivity (0.53 mS cm-1). Finally, a propensity for compositional variation in LLZTO powders and sintered ceramics was observed and for the first time explored in detail. By comparing LLZTO obtained from combustion, MSS, and SSR, a correlation between increased elemental inhomogeneity and reduced ionic conductivity is observed. Implications for garnet-based solid-state batteries and strategies to mitigate elemental inhomogeneity are discussed.
ContributorsWeller, Jon Mark (Author) / Chan, Candace K (Thesis advisor) / Crozier, Peter (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created2021
Description
Current Li-ion battery technologies are limited by the low capacities of theelectrode materials and require developments to meet stringent performance demands for future energy storage devices. Electrode materials that alloy with Li, such as Si, are one of the most promising alternatives for Li-ion battery anodes due to their high capacities. Tetrel (Si,

Current Li-ion battery technologies are limited by the low capacities of theelectrode materials and require developments to meet stringent performance demands for future energy storage devices. Electrode materials that alloy with Li, such as Si, are one of the most promising alternatives for Li-ion battery anodes due to their high capacities. Tetrel (Si, Ge, Sn) clathrates are a class of host-guest crystalline structures in which Tetrel elements form a cage framework and encapsulate metal guest atoms. These structures can form with defects such as framework/guest atom substitutions and vacancies which result in a wide design space for tuning materials properties. The goal of this work is to establish structure property relationships within the context of Li-ion battery anode applications. The type I Ba 8 Al y Ge 46-y clathrates are investigated for their electrochemical reactions with Li and show high capacities indicative of alloying reactions. DFT calculations show that Li insertion into the framework vacancies is favorable, but the migration barriers are too high for room temperature diffusion. Then, guest free type I clathrates are investigated for their Li and Na migration barriers. The results show that Li migration in the clathrate frameworks have low energy barriers (0.1- 0.4 eV) which suggest the possibility for room temperature diffusion. Then, the guest free, type II Si clathrate (Na 1 Si 136 ) is synthesized and reversible Li insertion into the type II Si clathrate structure is demonstrated. Based on the reasonable capacity (230 mAh/g), low reaction voltage (0.30 V) and low volume expansion (0.21 %), the Si clathrate could be a promising insertion anode for Li-ion batteries. Next, synchrotron X-ray measurements and pair distribution function (PDF) analysis are used to investigate the lithiation pathways of Ba 8 Ge 43 , Ba 8 Al 16 Ge 30 , Ba 8 Ga 15 Sn 31 and Na 0.3 Si 136 . The results show that the Ba-clathrates undergo amorphous phase transformations which is distinct from their elemental analogues (Ge, Sn) which feature crystalline lithiation pathways. Based on the high capacities and solid-solution reaction mechanism, guest-filled clathrates could be promising precursors to form alloying anodes with novel electrochemical properties. Finally, several high temperature (300-550 °C) electrochemical synthesis methods for Na-Si and Na-Ge clathrates are demonstrated in a cell using a Na β’’-alumina solid electrolyte.
ContributorsDopilka, Andrew (Author) / Chan, Candace K (Thesis advisor) / Zhuang, Houlong (Committee member) / Peng, Xihong (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created2021
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Passed in April of 2010, Arizona Senate Bill 1070 is nationally recognized as the first state-level anti-immigration legislation of its kind that deputized local police officers to enforce immigration laws. Though response strategies varied widely across activists and organizations, many community organizations devised strategies specifically aimed to protect and assist

Passed in April of 2010, Arizona Senate Bill 1070 is nationally recognized as the first state-level anti-immigration legislation of its kind that deputized local police officers to enforce immigration laws. Though response strategies varied widely across activists and organizations, many community organizations devised strategies specifically aimed to protect and assist the undocumented community during the reign of terror that accompanied SB 1070. In looking at the reflections of activists and organization leaders on their own actions and decision-making rationale, I analyze how their strategies and tactics worked to both counter and reconceptualize hegemonic notions of citizenship, belonging, and community through the creation of networks and knowledge funds. By specifically examining the efforts made by No Mas Muerte, Puente Human Rights Movement, and the Calle Dieciseis Mural Project, I show that efforts that go beyond voter mobilization and legal action, which not only work to combat dominant rhetoric but also center the voices of the targeted population through disrupting public space, are essential to responding to political efforts designed to target vulnerable communities. Given their necessity, academics and institutional actors must acknowledge the importance of grassroots efforts in contributing to inter-institutional strategies and ensure that a ground-up analysis of community-based organizations informs their actions taken against state-level anti-immigration laws.

ContributorsMorris, Jordan (Author) / Gomez, Alan (Abridger) / Brian, Jennifer (Committee member) / Barrett, The Honors College (Contributor) / School of Social Transformation (Contributor) / Historical, Philosophical & Religious Studies, Sch (Contributor)
Created2022-05