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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.
This dissertation describes three studies examining how people with developmental disabilities (DD) experience social capital from childhood to young adulthood. The first study follows PRISMA standards for scoping literature review to investigate social capital in DD research from childhood to emerging adulthood. Results describe social capital definition, measurement and application in DD research and identify gaps in the literature. The second study describes extracurricular activity (EA) participation of children with and without DD and the associations of childhood EA with mental health in young adulthood. Results show: differences in EA participation of children with and without DD; EA is associated with lower psychological distress and greater flourishing among people with and without DD. The third study uses photovoice to address the meaning of interdependence for college students with DD. Participants described their experiences using photos and stories. Themes included: openness to being helped, foundational role of families, experiencing new and challenging things, and tension between wanting to help and vulnerability of being a helper. Understanding social capital in the lives of people with DD can guide policies and supports, promoting improved quality of life. This research is a steppingstone toward a more inclusive and supportive society for people with DD.
This dissertation aims to contribute to our understanding of Chinese government engagement on social media platforms. In the first section, this dissertation proposes a fresh framework for identifying persuasive techniques in textual posts. In the second section, the dissertation investigates the similarities and differences in the Chinese government's posts across various platforms, each targeting distinct audiences. The final section of this dissertation provides a quantitative analysis of users' opinions towards the content produced by the Chinese government on online social networks.
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.
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.
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.
Chapter 2 explores the feasibility, requirements, and challenges associated with integrating AI capabilities into AR systems to enhance the safety of highway work zones. This chapter delves into the feasibility, requirements, and challenges associated with incorporating AI capabilities into the AR system to develop a predictive safety system that can proactively identify potential hazards and issue timely warnings to workers. The outcomes of this chapter indicate that the real-time communication latency and AI execution latency meet the tight timing constraints of a real-time safety system. The early user research demonstrates positive reception and acceptance of the proposed safety framework and interface by highway maintenance and operation professionals across multiple states in the US.
Chapter 3 focuses on conducting a mixed-method usability investigation of the proposed AR-based safety system using a high-fidelity prototype. The investigation assesses aspects such as user interface design, interaction patterns, and user feedback to evaluate the overall usability and effectiveness of the technology in enhancing roadway work zone safety. The findings indicate that participants rated the usability of the system above average in both indoor and outdoor settings and perceived a reasonable level of mental effort. Perceived trust was found to be significantly correlated with usability, underscoring its importance in user experience.
Chapter 4 examines the impact of different sensory modalities on worker reaction times in augmented reality warnings within roadway work zones. The analysis of data from experiments provides insights into the effectiveness of various warning modalities, including visual, audiovisual, haptic visual, and combined haptic audiovisual cues, in improving worker response times. The findings indicate that the haptic visual design elicited the fastest response on average among the participants, and its performance was comparable to that of the audio haptic visual design. Furthermore, both of these designs demonstrated significantly faster reaction times compared to visual and audiovisual warnings. The results also indicate that reaction times to augmented reality warnings in real-world outdoor scenarios were generally longer and exhibited greater variability compared to baseline desktop warnings and simulated AR in virtual reality. Surprisingly, VR simulated warnings did not show statistically significant shorter reaction times compared to their real-world counterparts. These observations suggest that simulating AR in virtual reality may not accurately replicate the reaction times observed in real-world situations.
Collectively, the results from these chapters demonstrate the usability, perceived safety benefits, and potential for timely notifications offered by the proposed AR-based safety system. This research also contributes to establishing best practices for designing time-sensitive safety systems, prioritizing situational awareness, and implementing worker-centered design principles in AR safety systems. Ultimately, the findings have the potential to significantly enhance the safety of highway workers and the broader workforce operating in roadway work zones.
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.
In recent decades, the demand for ultra-precise optical components with intricate geometric profiles has increased dramatically. Traditionally, polymer-based lenses have dominated the industry, but due to the benefits of using glass components, the demand for ultra-precision glass aspherical components has been rising consistently. When producing aspherical glass components, however, conventional manufacturing processes become time-consuming and expensive. Precision glass molding (PGM) technology offers an alternate method of production for aspherical glass lenses and irregular optical products. Compared to the conventional manufacturing process, it has the advantages of high forming accuracy, short manufacturing cycles, low cost, and high-volume production. However, the process has a few drawbacks, such as lens profile deviations, stress birefringence, etc. Before the glass molding process can be a viable option for mass-producing optical components, these drawbacks must be addressed. As such, a coupled thermo-mechanical finite element model is developed in this dissertation to simulate the precision glass molding process on two distinct glass varieties, D-ZK3 (CDGM) and P-SK57 (Schott). A novel testing method is developed to precisely characterize the viscoelasticity of the glass material. It is demonstrated that the obtained material parameters accurately depict the experimental data at various molding temperatures. In addition, the material testing experiments are designed to be implemented on a glass molding machine, simplifying the development and characterization of different moldable glass materials. The obtained material parameters are implemented in the finite element model to predict the profile deviation in the molded lens and compared with experimental results. A mold compensation technique is used to correct the mold profiles. The lens molded on the modified molds is shown in fall within the tolerance specifications. However, it was observed that the process parameters used during the molding process have an influence on the deviations and the stresses in the molded lens. Therefore, it is essential to optimize the molding process prior to implementing mold compensation techniques. The developed numerical model is used to analyze the impact of various process stages and parameters on the optical quality of molded lenses. Based on the observations, a modified molding process was developed which is shown to minimize the influence of the molding parameters on the deviations and the residual stress. In addition, it was demonstrated that the modified manufacturing process reduces the total cycle time for producing a glass lens of comparable optical quality by more than 50%, reducing the manufacturing cost of a molded glass lens.
