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Fluorinated Carbocations: Design, Synthesis, and Applications in Low-energy Photoredox Catalysis
No full textVisible-light photoredox catalysis has reshaped modern organic synthesis by enabling single electron pathways under mild conditions; however, many widely used systems still depend on high-energy blue light with limited photostability and narrow redox windows, constraints that can curtail functional-group tolerance, scalability, and compatibility with sensitive substrates. This dissertation addresses these limitations by introducing difluorinated carbocations as a tunable platform for low-energy photoredox catalysis. We have developed modular synthetic routes to fluorinated triaryl carbenium frameworks, including acridinium, helicenium, and triangulenium scaffolds that exhibit bathochromic shift in absorption and emission, useful excited-state lifetimes, and widened excited-state redox windows. Comprehensive characterization of the difluorinated azadioxotriangulenium 2FADOTA⁺, including steady-state absorption/emission, quantum yield, fluorescence lifetimes, cyclic voltammetry, and excited-state thermodynamics (Rehm-Weller analysis), establishes it as a strong orange-light photooxidant for organic transformations. The utility of 2FADOTA⁺ is demonstrated in two synthetically distinct and practically relevant transformations. First, we use 2FADOTA⁺ as a photocatalyst for the direct conversion of substituted furans to the corresponding pyrroles using readily available primary amines under orange-light irradiation (595 nm). Mechanistic evidence is consistent with initial photooxidation of the furan to its radical cation, nucleophilic capture by the amine, and subsequent Paal-Knorr condensation to deliver pyrroles under mild conditions. Second, we have developed an orange-light mediated direct arene C-H amination strategy that constructs aryl C-N bonds via arene radical-cation chemistry, enabling late-stage diversification of complex scaffolds under low energy conditions using 2FADOTA⁺. Across representative scopes, 2FADOTA⁺ mediates efficient conversions with predictable site-selectivity patterns characteristic of arene radical-cation intermediates, and the platform accommodates diverse amine partners and electron-rich arene/heteroarenes without requiring precious metals. Together, these studies establish fluorinated carbocations, exemplified by 2FADOTA⁺, as a general, designable platform for low-energy photoredox catalysis that decouples strong excited-state oxidizing ability from the need for high-energy excitation. Finally, we present preliminary results on red-light mediated C-H functionalization of furans using organic helicenium (nPr-DMQA⁺) as the photocatalyst
Improving Mental Health Provider Knowledge of Implicit Bias and Its Impact Through Trauma-Informed Learning
No full textBackground: Implicit bias, unconscious, negative attitudes toward marginalized populations, significantly contributes to disparities in mental health care. Mental health providers (MHPs) are particularly vulnerable to these effects, as psychiatric diagnosis and treatment rely heavily on subjective judgment. Bias can result in misinterpretation of symptoms, misdiagnosis, and reduced access to care, particularly among people of color, veterans, immigrants, and the unhoused. Trauma-informed care (TIC) provides a supportive framework for addressing bias by fostering provider self-awareness and promoting culturally responsive, equitable treatment. Educational strategies that attend to providers’ cognitive and emotional needs can increase receptivity to learning and applying bias-mitigation techniques. Purpose: This Doctor of Nursing Practice (DNP) project aimed to enhance MHPs’ knowledge, awareness, and attitudes related to implicit bias through a TIC training at a Tucson outpatient psychiatric clinic. In a racially and culturally diverse state such as Arizona, implicit bias contributes to diagnostic disparities and poor therapeutic outcomes. This project implemented an evidence-based educational intervention to help MHPs recognize and mitigate unconscious bias, improve cultural responsiveness, and promote health equity. The project evaluated changes in MHPs’ understanding of implicit bias before and after the intervention, with the goal of informing future practice integration and advancing trauma-informed, bias-aware care. Methods: This quality improvement project utilized a pre-/post-survey design to evaluate the impact of an asynchronous, trauma-informed implicit bias training for MHPs. The intervention included an evidence-based presentation addressing implicit bias, its clinical implications, and trauma-informed strategies. Surveys administered via Qualtrics measured changes in knowledge, awareness, attitudes, and intent to apply TIC principles. Data were analyzed using descriptive statistics and paired t-tests within a Plan-Do-Study-Act (PDSA) framework. Results and Conclusions: Of six eligible providers, three psychiatric mental health nurse practitioners completed both surveys. While knowledge scores remained uniformly high, significant improvements (p < .001) were observed in awareness, attitudes, and intent, with the largest gains in awareness. Findings suggest that brief, trauma-informed implicit bias training can strengthen reflective practice and reinforce providers’ commitment to equitable psychiatric care
Windows of Opportunity: Exploring How Home Practices Reframe Knowledge About High-Performance Retrofits
No full textIn hot, dry climates with older, uninsulated homes, high-performance windows can double or triple the effective insulation of the building enclosure and substantially reduce cooling loads from solar gain. Yet many households who choose to replace windows select lower-performing options, locking in higher energy use, reduced comfort, and greater carbon emissions. Previous work has sought to address this issue by developing a tool that quantifies personalized energy and non-energy benefits of high-performance window retrofits for consumers, based on the assumption that more information will shift consumer decisions. This study explores how different frameworks for understanding household window-replacement decisions can generate insights to inform the development of interventions that might effectively support higher-performance choices. Using interpretive analysis of fourteen semi-structured interviews with households in Tucson, Arizona considering window replacement, the study situates window replacement within the habitual, patterned performances of home improvement practices. A circuit-of-practice approach identifies three ways households integrate homes as material objects into daily life — domestication, configuration, and stewardship — and shows how each reconfigures the organizing principles through which consumers build knowledge about home projects. Analysis using concepts from Legitimation Code Theory reveals a code clash between these knowledge-building practices and the way the calculator frames its claims. The findings suggest pathways for resolving this clash and broadening the adoption of higher-performance window retrofits. The study contributes theoretical insight into how shifting social practices reshape knowledge practices and provides practical direction for developing interventions that more effectively support high-performance window retrofits and related home energy upgrades
Optimizing Membrane Processes for Sustainable Water and Wastewater Treatment
No full textWater scarcity is one of the most critical global challenges. However, there are also critical water challenges that are deeply connected to food and energy, as these resources are integral components of growth and human life. This dissertation focuses on developing simulation models to demonstrate membrane capabilities of a multitude of applications, including integration of solar energy with nanofiltration membranes to produce standalone fit-for-purpose systems for off-grid water and energy co-production, selective ammonia recovery via humidity-assisted sweeping gas membrane distillation (SGMD), and synthesizing membranes to improve ion selectivity. Off-grid solar nanofiltration units with co-production of water and energy was capable of achieving higher cost reduction compared to when having separate units for energy and water production. SGMD offers a compact, efficient alternative to air stripping for ammonia recovery in wastewater treatment, while minimizing energy loss (86% reduction) and enhancing ammonia recovery and reuse. Simulations of a hypothetical calcium-permeable reverse osmosis carrier-based membrane show that selective Ca²⁺ transport mitigates gypsum scaling and extends the achievable water recovery ratio. These advancements highlight the versatility of membrane processes in addressing critical challenges in resource recovery, decentralized water treatment, and optimized desalination processes. Additionally, the study critically evaluates the theoretical assumptions of the Donnan Steric Pore Model with dielectric exclusion in nanofiltration, enabling the development of a simplified predictive model. By advancing our understanding of membrane transport and properties, we can improve the design of membranes and increase the adoption of membrane technologies with sustainable systems, resource recovery, and water recovery.Release after 12/01/203
Spatial Awareness Integrated EHR: Effects on Nurse Usability, Efficiency, and Cognitive Load
No full textBackground: EHR usability challenges continue to impose cognitive strain and workflow inefficiencies on nurses in high-acuity settings. Poorly designed interfaces fragment data and increase documentation burden, contributing to fatigue and errors. Spatially aware EHRs (interfaces that visually align digital elements with the physical clinical environment) may enhance usability by promoting intuitive interaction, reducing mental effort, and improving accuracy and efficiency in nursing documentation.Purpose: This study evaluated how different EHR interface designs affect nurse usability, cognitive load, and documentation performance impact in simulated critical care settings. It aimed to compare the influence of interface design on task performance and cognitive burden for experienced ICU nurses. Methods: Thirty-six experienced ICU nurses participated in a randomized crossover study, completing standardized documentation tasks using both a Spatial Awareness Integrated Electronic Health Record (SAI) prototype and a linear interface design (LID). Paired t-tests and linear mixed-effects models analyzed within-subject differences. Quantitative measures included task completion time, accuracy, cognitive workload (NASA-TLX), usability (System Usability Scale [SUS]), perceived usefulness (TAM-PU), and behavioral intention to use (TAM-BI). Results: The SAI significantly reduced documentation time by 177 seconds per task (d = 0.88) and lowered NASA-TLX workload by about 19 points, exceeding the 10–15-point threshold considered practically meaningful. Accuracy rates were comparable across systems. Though not statistically significant, mean SUS scores favored SAI (77.99 ± 18.23) over LID (71.60 ± 20.82; p = .155). Perceived usefulness (TAM-PU) trended higher for SAI (3.72 ± 1.21 vs. 3.38 ± 1.14; p = .184). Behavioral intention (TAM-BI) was significantly greater for SAI (4.72 ± 0.93 vs. 3.76 ± 0.95; Δ = 0.96, 95% CI [0.55, 1.36]; p < .001; d = 0.72). Lower workload correlated with a stronger intention to adopt (r = – .64, p < .001). Conclusions: Spatially congruent interface design was associated with lower workload scores on the NASA-TLX, improved task efficiency, and higher ratings of usability and acceptance. By aligning the display with the clinical workspace and simplifying documentation pathways, spatially organized EHR layouts may help reduce documentation burden, enhance situational awareness, and support safer care in critical care environments.Release after 12/01/202
To Belief or Not to Belief: Educator Perspectives on Diversity
No full textThe purpose of this study was to examine how teachers’ political orientation (PO) and years of teaching experience relate to their personal and professional diversity beliefs. By examining these demographic variables, this research can contribute to the field by highlighting the central role of political orientation in shaping teachers’ diversity beliefs, suggesting that future studies should further explore how underlying belief orientations interact with political ideology to influence classroom practice and professional practice. Using a mixed-methods design, data were collected through surveys from active educators (n = 92) that included items on beliefs about diversity and through semi-structured interviews (n = 15). Results indicated that political orientation, rather than years of teaching, was most consistently associated with both personal and professional diversity beliefs. Qualitative findings reinforced these patterns, illustrating that teachers’ political worldviews shaped how they conceptualized and enacted diversity, equity, and inclusion (DEI) practices. These results highlight the centrality of underlying belief orientations in shaping educators’ perspectives on diversity. Implications for practice, limitations of the study, and recommendations for future research are discussed
Evolutionary Landscapes and Resurfacing Processes of Planetary Surfaces
No full textGeomorphology is the study of features on the surface of Earth and other planetary bodies. It is an important tool to study the evolution of solar system bodies, and how they relate to what we know about Earth. Spacecraft exploration has provided high-quality data leading to unprecedented discoveries about the geological inner-workings of other planets, moons, and bodies of the solar system. This dissertation presents a multi-faceted study of current geomorphology on planetary surfaces and how it can be used to determine past geologic history where little or no field data exists. This includes (1) using imagery to observe types of surface features, (2) analyzing how features are distributed over a planetary surface, (3) identifying processes that can cause local resurfacing on planetary surfaces, and (4) modeling how such processes may have altered the appearance of planetary surfaces. This dissertation has two main planetary focuses: (1) Mars, specifically the northern lowlands, and (2) Europa and the icy satellites. In Chapter 1, I summarize the state of knowledge about the northern plains on Mars and their past geologic history. I also summarize the current knowledge about Europa and the processes suggested to be active on the icy satellites. In Chapter 2, I present a study of pitted cones and their population alignments within Utopia Planitia (a northern plains’ basin) on Mars, along with a local geomorphologic map. In Chapter 3, I present the first global dataset of pitted cones on Mars using a deep learning technique. In Chapter 4, I study band-like features on the surface of Mars and use modeling to explore how they may have formed. In Chapter 5, I investigate how seismic shaking may be resurfacing local regions on icy satellites. In Chapter 6, I present the conclusions of this dissertation research and its implications for the remaining questions about planetary surfaces. Chapter 7 contains appendices and author contributions. Chapter 8 contains references
Investigating the Contributing Factors of Eye Movements and Stress on Navigation and Spatial Memory
No full textNavigation is a complex process that humans rely on daily, from driving to work to finding cereal in the grocery store. Successful navigation usually requires that one accurately remembers spatial information stored in spatial memory. Many factors can contribute to increasing or decreasing navigating success and forming spatial memory; the factors that are the focus of this dissertation were chosen for their pervasiveness in the human experience. The purpose of this dissertation was to investigate the factors of vision, aging, and stress to understand how each may help or hinder navigation. We were particularly interested in how much spatial information is encoded with the eyes and if any additional information can be learned by also moving one’s body, how this relationship changes with age, and how stress affects navigation in larger environments. We also aimed to capture the complex nature of navigation and spatial memory by designing experiments with more naturalistic paradigms to represent behaviors humans do everyday. In Chapter 2, we used mobile eye tracking glasses in a small real-world environment with younger adults to show that vision is sufficient to accurately remember object relationships when the room can be viewed from a single viewpoint. Self-motion cues from walking around the room did not help participants form more accurate spatial memories. Spatial memory of object locations also benefited from longer gaze times at encoding and the presence of nearby landmarks. In Chapter 3, we show how some of these relationships change with age and how some relationships remained the same in a cohort of older adults. For older adults, vision was also sufficient to form spatial memories, although older adults were less accurate in replacing objects than younger adults. However, longer times gazing at objects during encoding and the presence of landmarks near objects did not appear to benefit older adults’ spatial memory, in contrast to results obtained with younger adults. In Chapter 4, we discuss how eye movements during retrieval may play an active role in memory retrieval. Finally in Chapter 5, we investigate how stress affects navigation strategies in a large virtual environment that addresses limitations from past research that limit navigation choices. We taught participants two paths that differed in length and familiarity, administered a stressor, and measured navigation strategies. We successfully induced stress and found that navigation strategies were not altered by our stressors. Participants most often chose to navigate using the shorter learned path but did show a bias toward the more familiar path as well. These results show the importance of vision to form spatial memories and retrieve them, the changes in visual strategies with age, and the resilience of navigation strategies to our stressors.Release after 01/14/202
Transient and Persistent Dynamics of CEA PKC-δ Neurons
No full textThe central amygdala (CeA) has been shown to mediate a wide range of survival behaviors, but the circuitry that drives any specific behavior has remained elusive. Work manipulating genetically defined subsets of CeA neurons has proven fruitful for producing organized changes in behavior and is thought to define functional subsets in the CeA. Our work here focuses on the eating regulating Protein kinase C-delta (PKC-δ) expressing neurons. Proper regulation of eating behaviors is critical for survival, requiring both appropriate promotion and inhibition of food intake. PKC-δ neurons have been identified as a key regulator for eating suppression in anorexigenic conditions. However, not knowing the dynamics of these neurons during eating left a major knowledge gap in understanding how these neurons regulate food intake. Here, using in vivo microendoscope calcium imaging, we found that a subset of CeAPKC-δ neurons show a surprising transient activation that lasts only a few seconds during food approach. This transient activation is required for normal food intake in eating bouts. We also found that a subset of CeAPKC-δ neurons show persistent activation that lasts many minutes in response to satiation, either induced by intraperitoneal injection of cholecystokinin (CCK) or refeeding after fasting. The persistent neurons activated by CCK significantly overlap with those activated by LiCl, suggesting that some persistent populations might overlap. Our results also showed that these two subsets of CeAPKC-δ neurons with different dynamics are not related, suggesting that transient and persistent dynamics are represented by distinct neural ensembles that may play different roles in eating regulation. Finally, we show that these transient and persistent populations can be differentially regulated in two models of disordered eating, and that they may play a causative role in the connection between activity-based anorexia and wheel running.Release after 07/05/202
Your Home in the West: An Honest Telling of Farming Opportunities in Coconino County, Arizona
No full textThis manuscript is also subtitled: "The Land of Desire for the Man With Small Capitol", azu_azhs_ephemera_3, 8 pagesThis item is part of the Arizona Agriculture and Rural Life, 1820-1945 collection. For more information about this collection, email [email protected]