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- Member of: Artivate: A Journal of Entrepreneurship in the Arts
Description
The presence of inclusions embedded within a polymer matrix significantly influences the macro- and nano-scale properties of the matrix. Characterizing the mechanical properties of such inclusion-embedded matrices is crucial for their diverse applications. Atomic force microscopy (AFM) has the unique ability to nondestructively characterize local modulus and height contours of nanocomposite surfaces. While previous studies have established a strong correlation between nanoparticle dispersion and the mechanical properties of nanocomposites, the combined influence of structural effects and material properties convolutes precise characterization. This study aims to deconvolute the effects of the nanoparticle’s embedment depth and damaged polymer on force-displacement curves using finite element analysis (FEA) to simulate the probe-matrix interactions in AFM. Validation of the FEA models was conducted using the Derjaguin-Muller-Toporov (DMT) and Hertzian contact mechanics models. Indentations were modeled for polymer matrices with inclusions embedded at varying depths and damaged polymer to analyze linear and nonlinear material, geometric, and contact mechanics effects. Nonlinear material behavior was characterized using a bilinear elastoplastic stress-strain curve and yield strength derived from Hertzian contact theory and Tresca’s yield criterion. Results revealed that inclusion depth and damaged polymer have distinct and measurable impacts on force-displacement curves retrace slopes, offering insights to identifiable patterns in mechanical behavior.
ContributorsChurch, Jett (Author) / Wilbur, Joshua (Thesis director) / Yekani Fard, Masoud (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2025-05
Description
As climate change intensifies, behavioral flexibility is becoming an increasingly important strategy for ectothermic animals facing rising temperatures and environmental variability. Desert ecosystems, characterized by extreme temperatures, scarce water, and wide daily thermal fluctuations, push many organisms close to their physiological limits. In these environments, surface activity must be carefully balanced with refuge use to avoid overheating and dehydration. This study investigates the influence of seasonal and spatial variation on the activity patterns of two desert-dwelling rattlesnake species, Crotalus atrox and Crotalus pyrrhus, across Sonoran Desert sites with differing climatic conditions. Using Temperature-Based Activity Estimation (TBAE), we assessed surface activity in relation to temperature and rainfall. Our findings reveal that rainfall, rather than temperature, is the primary driver of rattlesnake surface activity, with C. atrox showing marked increases in activity following precipitation. Crotalus pyrrhus exhibited activity patterns similar to C. atrox populations in more arid regions, suggesting water availability may override species-level differences in shaping behavior. These findings provide insight into how environmental moisture influences the behavior and thermoregulation of desert ectotherms and may inform predictions of reptile responses to ongoing climate change.
ContributorsMiller, Carol (Author) / DeNardo, Dale (Thesis director) / Benson, Derek (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Sanford School of Social and Family Dynamics (Contributor)
Created2025-05
Description
Ecosystems are a community of living organisms interacting with their surrounding environment, working together as a functional unit of the biosphere. Ecosystems are complex and sensitive; a good example of this complexity is trophic cascades, a phenomenon where a shift in one species' population ends up affecting the lower trophic levels, creating a ripple effect (Carpenter). The loss of a "keystone" species, in particular, can drastically change the natural processes and the species makeup within an ecosystem. Apex predators, often seen as keystone species, have a major influence, especially over prey populations that would otherwise grow unchecked in their absence and everything below it in the food web, creating a domino effect.
One way to counteract these changes is through the introduction of an animal species into the ecosystem. However, this process must be done with thorough scientific research and should be approached carefully to ensure it benefits the environment rather than harms it. A strong example of this is the reintroduction of gray wolves into Yellowstone National Park after a fifty-year absence. Their disappearance had caused major problems—the elk population exploded, beaver numbers dropped, and vital plant life like aspen and willow trees became scarce. Once the wolves were reintroduced, the public was able to witness the benefits firsthand: the elk population was brought under control, foliage regrew, and habitats for lower trophic levels recovered. It’s important to recognize that introducing species doesn't always work out. In some cases, it leads to invasive species, like the feral pigs on Hawaiian islands or invasive bees in numerous countries, which cause even greater disruption. This only highlights the importance of extensive research and careful monitoring to counteract any potential harm caused.
While the positive effects of reintroducing a species can be significant, ecosystems take time to recover, and sometimes, they may never fully return to their original state—a process called hysteresis (Estes et al., 2011). Even if an ecosystem reaches a tipping point and shifts, the management of animal populations remains a key element in ecological restoration. By understanding these complex relationships and effects, we can create stronger conservation plans to minimize risks and support a healthier, more balanced environment.
ContributorsAlvarado, Ashley (Author) / James, Samantha (Thesis director) / Murphree, Julie (Committee member) / Barrett, The Honors College (Contributor) / School of Applied Sciences and Arts (Contributor)
Created2025-05
Description
Due to the natural abundance of sodium in the Earth’s crust and its low specific cost, new research has shown that Sodium Ion Batteries (SIBs) are an increasingly viable solution for sustainable energy storage. SIBs have the potential to be a more cost-effective alternative to Li-Ion batteries. However, there are several performance issues that hinder their charge capacity and capacity retention, largely attributed to electrode-electrolyte side reactions. In order to be effectively commercialized, these issues must be investigated, understood, and improved upon. It has been observed that the electrode-electrolyte interface (EEI) has a large impact on the overall cell performance in SIBs. While EEI layers are still trying to be fully understood, there is evidence that suggests electrolyte additives may assist the formation of synergistic EEI layers that can improve these major capacity issues in SIBs. Here, the use of three electrolyte additives (FEC, TMSB, and VC) with the MuNC cathode material is reported. From electrochemical cycling data, it was found that these additives greatly extend the lifetime of the MuNC cathode material. Further analysis is performed to understand the effectiveness of electrolyte additives as a solution to stability issues in Na-ion batteries.
ContributorsJacobs, Matthew (Author) / Mu, Linqin (Thesis director) / Chan, Candace (Committee member) / Barrett, The Honors College (Contributor) / Materials Science and Engineering Program (Contributor)
Created2025-05
Description
Fad diets are trendy, and come and go. They are a very profitable business to take part in. It is common for people to be against fad diets, yet so many people still try them. The people who try these diets are often vulnerable, trying to lose weight or to improve their health, and lack a foundation in nutrition knowledge. This makes them easy targets for the marketing of fad diets, which target people's fears and give them hope of improving their health. The people selling these diets misuse their credentials and data to provide their diets credibility that they are helpful and can do more than they do. People's cultures can also play into fad diets, especially with many cultures having a pressure to be thin.
ContributorsMorlock, Alexis (Author) / Connell, Janice (Thesis director) / McMullen, Mary (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor) / School of Social and Behavioral Sciences (Contributor) / School of Molecular Sciences (Contributor)
Created2025-05
Description
This study presents a novel approach to 4D printing by employing surface tension-assisted additive manufacturing to fabricate multi-material structures with tunable surface roughness in response to humidity. Poly(ethylene glycol) diacrylate (PEGDA) was selected as the material due to its hygro-responsive and photocurable properties. The photocurable resin was prepared by varying concentrations of PEGDA, deionized (DI) water, and photoinitiator (PI). The optimized curing and drying times on swelling behavior were studied. The optimal material—mixture of 30 wt% DI water and 0.1 wt% PI—demonstrated the highest swelling ratio while maintaining structural integrity. Vat photopolymerization (VPP) printing method was used to create mesh designs and surface tension-assisted manufacturing was utilized to suspend films of hygro-responsive material. Retentiveness testing showed that circular holes with smaller diameters retained the most material due to uniform tension distribution. The structures exhibited increased surface roughness upon swelling which confirmed the feasibility of the manufacturing methodology. This research suggests the potential for adaptive applications such as responsive grippers or movements with different patterned surface roughness. Future work will focus on improving mechanical properties such as adhesion between different materials and structural brittleness and optimizing fabrication processes through the usage of hydrophobic coatings.
ContributorsYoo, Minju (Author) / Li, Cindy (Thesis director) / Tang, Tengteng (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / The Design School (Contributor)
Created2025-05
Description
The influence of TV shows on career interest is a topic that has little been studied. This experiment tested the hypothesis that exposure to a TV genre increases career interests in related fields. Participants (N = 272) were randomly assigned to one of three conditions that manipulated their exposure to a TV genre. In one condition, participants (N = 96) watched a video clip of CSI: Miami, which was selected to represent TV genres related to careers in forensic science. In a second condition, participants (N = 93) watched a video clip of Suits, which was selected to represent TV genres related to careers in corporate law. In a third, control condition, participants (N = 83) did not watch a video. Participants in the CSI and Suits conditions reported their career interests before and after watching the video clip. Because participants in the control did not watch a video clip, they only reported their career interests once. The results found partial evidence that TV shows influence career interests. Methodological and conceptual explanations for the nonsignificant effects are discussed.
ContributorsSimonson, Colin (Author) / Madon, Stephanie (Thesis director) / Ranadive, Anjali (Committee member) / Barrett, The Honors College (Contributor) / School of Interdisciplinary Forensics (Contributor)
Created2025-05
Description
The rise of generative AI and large language models in the past couple of years has impacted various industries. This study investigates how generative artificial intelligence has transformed the landscape of phishing attacks, reshaping both the methods employed by attackers and the strategies required for defense. Through in-depth interviews with five cyber security experts, the research explores how generative AI enhances the sophistication, scalability, and personalization of phishing campaigns, enabling attackers to craft highly convincing messages that bypass traditional detection methods. On the defensive side, the study highlights both the capabilities and limitations of current tools and emphasizes that continuous employee training and a strong cybersecurity culture remain essential components of an effective defense strategy. This research contributes to the understanding of how generative AI amplifies both the threat and the defense in modern phishing, offering key insights for organizations aiming to adapt to an evolving cyber threat landscape.
ContributorsSakalkale, Reva (Author) / Sopha, Matthew (Thesis director) / Sulla, Chistopher (Committee member) / Barrett, The Honors College (Contributor) / The Design School (Contributor) / Department of Information Systems (Contributor)
Created2025-05
Description
This thesis project utilizes value investing principles to compare the financial success of Walmart and Costco. These principles are used to compare the performance of two similar business models in the retail industry by comparing Sam’s Club and Costco. Lastly, this thesis project explores which valuation method, among those commonly used in value investing, performs most reliably in reflecting the intrinsic value of Costco and Walmart
ContributorsOnat, Can (Author) / Liu, Carol (Thesis director) / Rykaczewski, Maria (Committee member) / Barrett, The Honors College (Contributor) / School of Accountancy (Contributor) / Department of Information Systems (Contributor)
Created2025-05
Description
Anne-Marie Slaughter’s “Why Women Can't Have It All” argues that structural barriers hinder women from balancing career and family life. This study challenges the idea that women can freely define and achieve “having it all,” highlighting the societal expectations and limitations still placed on working mothers. Through interviews with ten mother-daughter pairs, the research explores how mothers navigated work-life balance and societal criticism, and how their choices shaped their daughters’ views on womanhood, work, and family. The study emphasizes that “having it all” is a personal and evolving concept, shaped by individual experiences and cultural shifts. By capturing these intergenerational perspectives, this thesis aims to empower women to define success on their own terms, resisting narrow societal norms and embracing a broader, more inclusive vision of fulfillment.
ContributorsEubank, Cara (Author) / Woodall, Gina (Thesis director) / Lennon, Tara (Committee member) / Barrett, The Honors College (Contributor) / School of Politics and Global Studies (Contributor) / School of Criminology and Criminal Justice (Contributor)
Created2025-05