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There have been an increasing number of materials developed that show multifunctional chromogenic properties (such as electrochromism, electrofluorochromism, or photochromism), but to date, few materials have shown all three properties. Materials that are electrochemically and optically active are attractive for a diverse set of applications that include smart-windows, lighting, sensing, energy production, and conservation. Achieving systems made from organic, cost-effective, readily synthesized materials would make them easy to utilize in a variety of fields. Multifunctional chromogenic dipyridinium thiazolo(5,4-d)thiazole (TTz) show promise in achieving these needs as they offer high contrast color change, high fluorescent quantum yields above 90%, and water processability while made from inexpensive starting materials. The planar, rigid, heterocyclic TTz core improves stability and reversibility as the TTz reduces from yellow TTz2+ to purple TTz•+ to blue TTz0 compared to other viologen systems.
When implemented in a low-cost poly(vinyl alcohol) (PVA)/borax hydrogel device using conductive glass electrodes, the TTz can change color and fluorescence intensity with applied voltage or light exposure. The electrochromism offers 75% transmittance contrast that is stable for 250 on/off cycles and electrofluorochromism with >90% contrast. By adjusting gel components and coating/drying the hydrogel, a variety of photochromic thin films were produced. Remarkably, the TTz-embedded films retain their high contrast chromogenic properties showing photochromism (yellow TTz2+ to blue TTz0 color change) and photofluorochromism after only one minute of light exposure. After turning blue, the oxidation back to yellow occurs through interactions with oxygen. This is potentially an effective way to optically gauge the presence of oxygen which is useful for a variety smart packaging applications for food, pharmaceuticals, and electronics. The color change speed and contrast can be tuned by adjusting borax and TTz concentrations. Because the TTz’s show multifunctional capabilities, photo-charging battery devices are tested to indicate the creation and storage of electrical charge when illuminated. When paired with the appropriate catholyte and membrane, TTz shows evidence of photocharging in hydrogel and film devices. Comparing charge discharge curves of the battery devices, illumination can increase voltages by 0.2 V and improve charging capacity. This work shows the remarkable multifunctional electroactive and photoactive properties of dipyridinium thiazolothiazole materials as well as their implemented to yield reversible, high contrast electrochromism, electrofluorochromism, photochromism, photofluorochromism, and light responsive charging.
In contemporary society, individuals with substance abuse histories face a multitude of challenges that extend far beyond the physical and psychological effects of addiction. As they embark on the path of recovery and strive for reintegration into society, they are confronted with an additional formidable barrier: the pervasive stigma and discrimination that persistently accompany their past struggles. This dissertation seeks to illuminate the profound impact of stigma and discrimination on individuals with substance abuse histories, exploring the underlying factors that perpetuate these harmful attitudes, and proposing potential strategies to alleviate their burden. Comprised of three interconnected papers, this research analyzes trust dynamics, stigma, and social support towards this population, offering valuable insights for combating stigma and fostering a more inclusive and compassionate society.
The first paper focuses on the power of positive information to counteract negative stereotypes and enhance trust in everyday interactions involving individuals with substance abuse histories. By examining the ways in which positive information can mitigate stigmatizing perceptions, this paper uncovers strategies to promote understanding and empathy in social encounters, paving the way for more meaningful connections and reduced discrimination.
Moving forward, the second paper explores participants' perceptions of trust and trustworthiness when engaging with partners who possess varying substance abuse histories in a trust game. By investigating how participants' knowledge of their partners' backgrounds influences expectations of reciprocity and trustworthiness, this paper unravels the complex dynamics that shape interpersonal relationships. The findings shed light on the potential for shifting perceptions and dismantling biases, ultimately fostering an environment where trust can flourish. Lastly, the third paper investigates the social and relational factors that influence cooperation and support for individuals with substance abuse histories within familial and friendship networks. By identifying the barriers that hinder cooperation and providing recommendations for creating supportive environments, this paper aims to strengthen social support networks and facilitate a more compassionate and inclusive community for individuals in recovery.
Collectively, these three papers contribute to the broader goal of combating stigma, building trust, and fostering cooperation towards individuals with substance abuse histories. The findings underscore the pivotal role of positive information, perceptions of warmth and trustworthiness, and the significance of individual attitudes and social support networks in reducing stigma and cultivating an environment that embraces recovery. By revealing the complexities of stigma and discrimination, this dissertation aspires to inform policies, interventions, and societal attitudes that empower individuals with substance abuse histories to thrive and reintegrate into society with dignity and respect.
Global warming and climate change keep causing a catastrophic impact on the natural, social, economic, and political environment in many parts of the world. The urgency for the transition to a low-carbon economy through CO2 emissions reduction calls for innovative methods to harvest renewable energy sources to displace unsustainable fossil fuel power in North America. This work presents proposed methods for marine hydrokinetic and solar renewable power generation. On another front, since addressing the causes of global warming and climate change is not timely enough, this author proposes technologies to minimize their effects, which manifest through extreme weather events. Since renewables harvesting generates variable power profiles during extreme weather events, this work investigates high voltage interconnectors to smooth the total power variability of wind power farms far distant between themselves under hurricane events. Another effect of climate change is the increasing frequency of failures on overhead transmission lines due to extreme weather events. The author thus proposes a wide-area controller with phasor measurement and battery actuator to minimize the post-fault transients.
At-home DNA testing and sharing in public genealogy databases are becoming widespread. This will facilitate finding out ancestry, genetic relatives, biological parents, making new connections, advancing medicine, and determining predisposition to various diseases and health issues. While the biomedical community glorifies the uses of the genomics revolution, the expanded obtainability of such sensitive data has substantial implications for individual privacy as genes carry sensitive personal information about human traits and predispositions to any diseases. Furthermore, DNA data has identification capability (e.g., forensics) as well as reveals familial interconnections. However, commercial DNA testing is not vigorously governed by any laws and policies. The privacy implications of public DNA data sharing remain largely unexplored. This dissertation explores users' privacy concerns and proposes a method for communicating the risks to users to inform users when sharing their DNA data.
In the first study, we explored users' perceptions regarding DNA data. We asked about their views of at-home DNA testing and sharing, followed by their expected benefits and concerns. We also talked about public genealogy databases like GEDmatch. We focused on understanding the users' preferences and perceptions on the disclosure of their genetic information under the different types of platforms and entities. Our results show that users are mostly unaware and uncomprehending of the interconnected nature of genetic data. We noted users' general perceptions and focused on understanding their preferred privacy controls while sharing their DNA data, their desired settings, policies, and rules.
From this study, we identified the need to develop a privacy-enhancing technology such that the users can make an informed choice while sharing DNA data. We also found that several policies and settings should be to preserve the privacy of sensitive data. With these findings in mind, the ultimate objective of this dissertation is to design and implement privacy risk communication methods that aid users in comprehending the risks and benefits associated with sharing DNA data, as well as enhancing transparency in access control. To evaluate the effectiveness of our developed risk communication approach, we deployed it within an existing platform, allowing us to assess users' decision-making processes and gain a deeper understanding of the nature of DNA data.
Access to inclusive school settings is associated with many benefits for students with intellectual and developmental disabilities in the areas of academics (Agran et al., 2020; Kurth & Mastergeorge, 2010), social skills (Kleinert et al., 2015; Lyons et al., 2011; Schwab et al., 2015), and communication skills (Ballard & Dymond, 2017; Kleinert et al., 2015), among others. However, challenging behavior serves as a major barrier to inclusive school settings for some students with IDD (Agran et al., 2020; Gee, 2020; Giangreco, 2020; Kleinert, 2020). Given the benefits associated with access to inclusive school settings, it is critical that this barrier is addressed. One way in which challenging behavior can be addressed in school settings, including inclusive school settings, is through the use of function-based interventions. Function-based interventions are targeted interventions that are based on the results of a functional behavior assessment and are aligned with the function of a student’s challenging behavior (Gage et al., 2012; Jeong & Copeland, 2020). It is critical that the contextual fit of a function-based intervention is considered, as interventions that take contextual fit into consideration are more effective than those that do not (Monzalve & Horner, 2021). Functional communication training is an example of a highly effective function-based intervention that is implemented to teach functionally equivalent, socially appropriate communication skills and address challenging behavior. The literature on the effectiveness of functional communication training spans across age groups, settings, interventionists, and disability categories (Cooper et al., 2020; Hume et al., 2021), including students with intellectual and developmental disabilities (Andzik et al. 2016; Walker, Lyon, et al., 2018). Although there is emerging evidence demonstrating the effectiveness of functional communication training implemented with students with intellectual and developmental disabilities in inclusive school settings (Masud et al., 2022), the research is very limited. Further, there are no functional communication training studies that focus on a peer as an interventionist. The current study extends the literature on functional communication training for students with intellectual and developmental disabilities by demonstrating implementation by a peer mentor in an inclusive high school setting. The purpose of this study was to examine the effects of peer-delivered functional communication training on the functionally equivalent communication responses and challenging behavior of a high school student with intellectual and developmental disabilities, the collateral effects of the intervention on various student communication behaviors, and the degree to which educator team member participants and student participant found the intervention to be socially valid. Results of this study indicated that the functional communication training intervention had no effect on student functionally equivalent communication responses or challenging behavior. However, there is evidence of positive collateral effects as the student participant’s rates of various communication behaviors increased after the intervention was implemented. Finally, all participants found the intervention to be socially valid across most measures, though there were some concerns about the limited amount of time and potential student discomfort. The dissertation includes a discussion of each of the research questions, limitations of the study, directions for future research, and implications for practice.
Plant-specialized metabolites play pivotal roles in adapting to dynamic environments and promoting human health. Among these metabolites, glyceollins and soyasaponins hold particular importance in responding to environmental stresses and contributing to sustainable human nutrition, including the development of novel pharmaceuticals. Glyceollins are phytoalexins induced in legume species, derived from the isoflavonoid branch of the phenylpropanoid pathway, while soyasaponins belong to the triterpenoid class and are naturally abundant in legume species without requiring induction. Despite their significance, the genetic basis underlying glyceollin induction and soyasaponin biosynthesis remains poorly understood. Furthermore, previous studies on their genetic basis have primarily focused on model or major crop species, with limited research on wild crop species, such as wild soybean. To address these knowledge gaps, our study utilized wild soybeans, known for their abundant and unexplored genetic diversity compared to cultivated soybeans, to unravel the genetic basis of glyceollin induction and soyasaponin production. We employed a metabolite-based genome-wide association (mGWA) approach and identified eight SNPs on chromosomes 3, 9, 13, 15, and 20 significantly associated with glyceollin induction. Six genes near a significant SNP (ss715603454) on chromosome 9 formed two clusters, encoding enzymes of the glycosyltransferase class. Furthermore, we discovered transcription factor genes, such as MYB and WRKY, within the linkage disequilibrium of the significant SNPs on chromosome 9. Epistasis and strong selection signals were also detected for the four significant SNPs on chromosome 9, indicating their role as major evolutionary factors influencing glyceollin variation in natural populations. Moreover, to investigate the genetic basis of phytochemical diversity, we conducted comprehensive phenotyping using LC-MS analysis on an association panel of 190 wild soybean ecotypes from diverse natural environments. Among the 874 metabolite peaks detected, we successfully annotated 485 metabolites. We identified 1155 SNPs significantly associated with 359 metabolites by performing a genome-wide association study. Clustering analysis revealed eight QTLs, named QTL-multiple metabolite clusters, showing significant associations with identified metabolites. By mining data within the linkage disequilibrium blocks encompassing these QTLs, we identified 612 annotated genes. From this set, we selected 16 candidate genes based on their relevance to the triterpenoid and phenylpropanoid-derived isoflavonoid biosynthetic pathways. Among these 16 candidate genes, UDP-dependent glycosyltransferase (UGT) was considered a promising candidate gene. Sequence analysis of this UGT gene in 46 wild soybean ecotypes unveiled two haplotypes with three SNPs on exon-1, leading to amino acid changes. The following association analysis showed these two haplotypes were significantly associated with high and low soyasaponin production. These two haplotypes also exhibited notable differences in expression levels. Our findings contribute valuable insights into the genetic mechanisms underlying phytochemical diversity, specifically the induction of glyceollins and the production of soyasaponins. This knowledge is instrumental in developing climate-resilient, high-value crops with enhanced medicinal properties, ultimately benefiting both plant and human health.
Human-AI co-creativity involves a human and an AI collaborating as partners on creative tasks such as generating music or art. This research domain is particularly timely as AI becomes increasingly prevalent in collaborative spaces. With the availability of ChatGPT, DALL.E 2 and other generative AI tools, co-creative AI is gaining increased popularity. Unlike general human-computer interaction, human-AI co-creation establishes a complex relationship where AI actively contributes, assumes human-like roles, and generates novel content blended with the user's contribution. Therefore, designing engaging and ethical co-creative systems poses challenges due to the open-ended nature of human-AI interaction. This dissertation contributes empirically and theoretically to the design of engaging and ethical human-centered co-creative AI. It focuses on four main areas: designing interaction, the impact of AI-to-human communication, ethical guidelines and understanding users' mental models of co-creative AI in human-AI co-creation. Firstly, this dissertation introduces the Co-Creative Framework for Interaction Design (COFI), which describes the broad range of possibilities for designing interactions in co-creative AI. Additionally, an analysis of 92 existing co-creative AI identifies common interaction design trends and research gaps. The analysis reveals a notable gap in commonly employed interaction designs: the absence of two-way communication between humans and AI, where AI cannot communicate with humans, limiting their potential as partners. Inspired by the research gap identified, this dissertation delves into examining the impact of AI-to-human communication on user experience and perception of co-creative AI. Two prototypes of a co-creative system, with and without AI-to-human communication, were developed to facilitate a comparative study. The results show improved collaborative experience and user engagement with the AI that can communicate. Moreover, the results shed light on emerging ethical concerns alongside increased user engagement. Inspired by the findings, this dissertation further explores the ethical challenges in human-AI co-creation by taking a human-centered approach. A design fiction study is presented to explore several ethical dilemmas and challenges in human-AI co-creation from the perspective of potential users. Findings provide potential users' perspectives, stances, and expectations, serving as a foundation for designing human-centered ethical AI partners in human-AI co-creation. Finally, this dissertation investigates users' mental models of co-creative AI, a crucial aspect of designing human-centered co-creative AI. A survey study is used to delve into users' mental models of co-creative AI and their association with user demographics to identify ways to design value-sensitive co-creative AI. The results also lay the groundwork for future research on personalized and adaptive co-creative AI in human-AI co-creativity.
The need for ultra-precision optical components with intricate geometric profiles has grown rapidly in the last few decades. Applications of precision optical lenses range from consumer electronic products to optical sensing instruments, microscopy, astronomy, etc. Typically, polymer-based lenses have been used and have dominated the industry so far, but due to the advantages of using glass components, the demand for ultra-precision glass aspherical components has been steadily raising. In fact, it is estimated that the demand for aspherical glass lenses will grow at a rate of 6.5% in the next five years. However, the conventional manufacturing processes when used for producing aspherical glass components become time-consuming and expensive.
Precision glass molding (PGM) technology provides an alternative manufacturing technique to fabricate aspherical glass lenses and irregular optical products. It has the advantages of high forming accuracy, short manufacturing cycles, low cost, and high volume production compared to the traditional manufacturing process. However, the process has a few drawbacks such as lens profile deviations, stress birefringence, etc. Typically, the mold surfaces are machined to be exact negatives of the required lens profile, assuming the lens would take the shape of the molds. But in reality, the complex mechanical behavior of the glass and its high-temperature dependence affects the final lens profile at room temperature. In addition to geometric deviations, the rapid temperature changes, often as much as several hundreds of degrees, in a short time affect the performance of the molded lens. These drawbacks need to be addressed before the glass molding process can be used as a viable option for mass-producing optical components.
As such, in this dissertation, a coupled thermo-mechanical finite element model is established to simulate the precision glass molding process on two different glass types, D-ZK3 (CDGM) and P-SK57 (Schott). The glass is modeled as a thermo-viscoelastic material by defining the stress and structural relaxation parameters. A new testing technique based on the cylinder compression test is developed in this study to extract the viscoelastic parameters at different temperatures. The obtained material parameters when used in the numerical simulations showed a good agreement with the experimental data throughout the testing temperature range. Further, the viscosity of the glass (a highly sought-after property of glass in precision molding) is obtained as a by-product of the proposed material calibration test. Finally, the structural relaxation parameters are obtained from the impulse excitation test based on ASTM standard E1876. All the experiments required for fully calibrating the viscoelastic response of the glass are performed on a precision glass molding machine, Moore Nanotech GPM170 machine. The obtained material parameters are used in the finite element model to predict the lens deviations and the stresses in the molded lens. A mold compensation technique is used to correct the mold profiles for any deviations. The lens molded using the corrected molds is shown to fall within the designer's specifications.
The process parameters used during the molding process play a vital role in determining the profile accuracy and the optical quality of the molded lens. Hence, it is important to determine an optimal parameter set before applying any mold compensation techniques. But due to the obscure and complex nature of the process, determining the parameter sets empirically is a tedious process. As such, in this study, the developed numerical model is used to individually analyze the different process steps and the corresponding process parameters on the profile deviations and the residual stresses in the molded lens. The results obtained in this study can be used as a reference to fast-track the manufacturing process.
Learning prepositions is very important for students with an intellectual disability to engage in functional communication behaviors. In addition, it is important for the students with intellectual disability to engage in physical activity at school because they spend the majority of their waking hours during weekdays at school. One way to increase both academic learning and physical activity level is to combine academic core content learning with physical activity. Simultaneous prompting is one of the response prompting procedures, which are evidence-based practices, and has been used as an effective way to teach both academic core contents and functional skills to students with intellectual disability. Peer tutoring also has been an effective teaching strategy to increase social aspects as well as academic learning for students with intellectual disability. In this study, I used a single-case multiple probe across participants design to examine the effects of a peer-delivered simultaneous prompting procedure in teaching locative prepositions combined with movement skills to students with intellectual disability. Five elementary school students with a mild to moderate intellectual disability participated in this study as the target participants. One peer without a disability enrolled in the same school with the target participants was the peer tutor and a data collector. The special education teacher participated in social validity data collection. Results of the study demonstrated a functional relation between the first primary dependent variable (i.e., action of prepositions to verbal prompt) and the intervention. Three out of five target participants showed some improvement in responding to nontargeted information (i.e., labeling of prepositions). For the movement skills measured by the Test of Gross Motor Development (TGMD; Ulrich, 2000), all target participants acquired higher scores in the posttest compared to their pretest scores. Further, four out of five target participants demonstrated some improvement in generalizing their knowledge of action of prepositions to verbal prompt to other materials and three target participants showed improvement in generalizing their knowledge of labeling of prepositions to other materials. Social validity data collected from the special education teacher, the peer tutor, and the target participants showed that they agreed the intervention was beneficial to all participants academically and socially. In addition, throughout the study, the peer tutor conducted both probe and training sessions with high procedural fidelity data. Limitations of the current study and suggestions for future research are discussed.
