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Description
The purpose of this study was to observe the effectiveness of the phenylalanyl arginine β-naphthylamide dihydrochloride inhibitor and Tween 20 when combined with an antibiotic against Escherichia. coli. As antibiotic resistance becomes more and more prevalent it is necessary to think outside the box and do more than just increase the dosage of currently prescribed antibiotics. This study attempted to combat two forms of antibiotic resistance. The first is the AcrAB efflux pump which is able to pump antibiotics out of the cell. The second is the biofilms that E. coli can form. By using an inhibitor, the pump should be unable to rid itself of an antibiotic. On the other hand, using Tween allows for biofilm formation to either be disrupted or for the biofilm to be dissolved. By combining these two chemicals with an antibiotic that the efflux pump is known to expel, low concentrations of each chemical should result in an equivalent or greater effect on bacteria compared to any one chemical in higher concentrations. To test this hypothesis a 96 well plate BEC screen test was performed. A range of antibiotics were used at various concentrations and with varying concentrations of both Tween and the inhibitor to find a starting point. Following this, Erythromycin and Ciprofloxacin were picked as the best candidates and the optimum range of the antibiotic, Tween, and inhibitor were established. Finally, all three chemicals were combined to observe the effects they had together as opposed to individually or paired together. From the results of this experiment several conclusions were made. First, the inhibitor did in fact increase the effectiveness of the antibiotic as less antibiotic was needed if the inhibitor was present. Second, Tween showed an ability to prevent recovery in the MBEC reading, showing that it has the ability to disrupt or dissolve biofilms. However, Tween also showed a noticeable decrease in effectiveness in the overall treatment. This negative interaction was unable to be compensated for when using the inhibitor and so the hypothesis was proven false as combining the three chemicals led to a less effective treatment method.
ContributorsPetrovich Flynn, Chandler James (Author) / Misra, Rajeev (Thesis director) / Bean, Heather (Committee member) / Perkins, Kim (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The purpose of this research is to explore Latina/o students' involvement at Arizona State University West and how it affects their sense of belonging, and thereby, their retention. I operationalize a "sense of belonging" as being able to express and feel comfortable with one's ethnic identity in the context of a higher education institution (Hurtado, 1997). I operationalize student involvement by the extent to which an individual student is devoted to their academic experience, invests time studying on campus, participates in student organizations, and interacts with faculty and their peers (Astin, 1984). I draw from Astin's theory of student involvement and Hurtado's sense of belonging as a base for this inquiry because they are critical components to understanding retention among the Latino/a community at Arizona State University West.
ContributorsGuerra, Luis D. (Author) / Cuadraz, Gloria (Thesis director) / Aska, Cassandra (Committee member) / School of Social and Behavioral Sciences (Contributor) / School of Humanities, Arts, and Cultural Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
An in-depth analysis on the effects vortex generators cause to the boundary layer separation that occurs when an internal flow passes through a diffuser is presented. By understanding the effects vortex generators demonstrate on the boundary layer, they can be utilized to improve the performance and efficiencies of diffusers and other internal flow applications. An experiment was constructed to acquire physical data that could assess the change in performance of the diffusers once vortex generators were applied. The experiment consisted of pushing air through rectangular diffusers with half angles of 10, 20, and 30 degrees. A velocity distribution model was created for each diffuser without the application of vortex generators before modeling the velocity distribution with the application of vortex generators. This allowed the two results to be directly compared to one another and the improvements to be quantified. This was completed by using the velocity distribution model to find the partial mass flow rate through the outer portion of the diffuser's cross-sectional area. The analysis concluded that the vortex generators noticeably increased the performance of the diffusers. This was best seen in the performance of the 30-degree diffuser. Initially the diffuser experienced airflow velocities near zero towards the edges. This led to 0.18% of the mass flow rate occurring in the outer one-fourth portion of the cross-sectional area. With the application of vortex generators, this percentage increased to 5.7%. The 20-degree diffuser improved from 2.5% to 7.9% of the total mass flow rate in the outer portion and the 10-degree diffuser improved from 11.9% to 19.2%. These results demonstrate an increase in performance by the addition of vortex generators while allowing the possibility for further investigation on improvement through the design and configuration of these vortex generators.
ContributorsSanchez, Zachary Daniel (Author) / Takahashi, Timothy (Thesis director) / Herrmann, Marcus (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The objective of this project was to design an electrically driven centrifugal pump for the Daedalus Astronautics @ASU hybrid rocket engine (HRE). The pump design was purposefully simplified due to time, fabrication, calculation, and capability constraints, which resulted in a lower fidelity design, with the option to be improved later. The impeller, shroud, volute, shaft, motor, and ESC were the main focuses of the pump assembly, but the seals, bearings, lubrication methods, and flow path connections were considered as elements which would require future attention. The resulting pump design is intended to be used on the Daedalus Astronautics HRE test cart for design verification. In the future, trade studies and more detailed analyses should and will be performed before this pump is integrated into the Daedalus Astronautics flight-ready HRE.
ContributorsShillingburg, Ryan Carl (Author) / White, Daniel (Thesis director) / Brunacini, Lauren (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
In today’s economy, advertisers understand that sex sells. The foundations of this concept, however, are influenced by patriarchal expectations that women are first and foremost sexual objects for men. Women are sold beauty and demeanor expectations for them to utilize when making themselves attractive for men and men are sold the idea of beautiful, docile women. This dynamic perpetuates strict definitions of acceptable gender displays and reinforces socially permitted gendered behavior. As a society in the 21st century, we understand the damage of sexist ideals, but where we fall short is in the monitoring of channels that perpetuate and maintain those stereotypes and how affected the public really is by the male gaze, and lack of a female gaze, in media. In this paper, I search for a female gaze, but in doing so recognize the inequalities inherent in yet another gendered practice of looking and instead steer the conversation towards personalized perspectives informed by an understanding of the dominant practice of looking and its inverse.
The primary perspective from which people are depicted in media today is shaped by the male gaze. The male gaze is comprised of patriarchal ideals and relies on the understanding that the spectator or viewer is a standard human being, which heteronormativity tells us is a man. From this perspective, the scope of visual representations of men and women in media has been molded after the hierarchized gender displays within which masculinity has primacy over femininity. By presenting a limited spectrum of behavior acceptable for men and women, the media hegemonically manipulates the social constructs of gender and gendered behavior across all levels of society.
This honors thesis applies semiotic and feminist methodologies to engage visual forms of media through art, film, and social media to challenge the social constructs of gender perpetuated and reinforced by dated stereotypes of gender and gendered behavior. First, the theoretical foundation will provide a framework for semiotic and feminist analysis of visual representations of gender in media. Then, I will present data representing the real-world impact that this social construction of gender has on adolescents in America using The State of Gender Equality for U.S. Adolescents, published by Plan International Inc. I will then bring together the explicated methodologies and evidential data alongside my own experiences as a female consumer of visual media to reveal alternative practices of looking that do not revolve around patriarchal norms, looking for a female gaze. In doing so, I hope to present recourse in the face of persistent use of sexist imagery across all levels of our culture and every medium of visual self-expression by providing tools that can be used to interrogate gendered perceptions and inform self-examination in pursuit of a feminist practice of looking.
The primary perspective from which people are depicted in media today is shaped by the male gaze. The male gaze is comprised of patriarchal ideals and relies on the understanding that the spectator or viewer is a standard human being, which heteronormativity tells us is a man. From this perspective, the scope of visual representations of men and women in media has been molded after the hierarchized gender displays within which masculinity has primacy over femininity. By presenting a limited spectrum of behavior acceptable for men and women, the media hegemonically manipulates the social constructs of gender and gendered behavior across all levels of society.
This honors thesis applies semiotic and feminist methodologies to engage visual forms of media through art, film, and social media to challenge the social constructs of gender perpetuated and reinforced by dated stereotypes of gender and gendered behavior. First, the theoretical foundation will provide a framework for semiotic and feminist analysis of visual representations of gender in media. Then, I will present data representing the real-world impact that this social construction of gender has on adolescents in America using The State of Gender Equality for U.S. Adolescents, published by Plan International Inc. I will then bring together the explicated methodologies and evidential data alongside my own experiences as a female consumer of visual media to reveal alternative practices of looking that do not revolve around patriarchal norms, looking for a female gaze. In doing so, I hope to present recourse in the face of persistent use of sexist imagery across all levels of our culture and every medium of visual self-expression by providing tools that can be used to interrogate gendered perceptions and inform self-examination in pursuit of a feminist practice of looking.
ContributorsPreston, Phoebe Jane (Author) / Gaffney, Cynthia (Thesis director) / Kirsch, Sharon (Committee member) / School of Humanities, Arts, and Cultural Studies (Contributor) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Human habitation of other planets requires both cost-effective transportation and low time-of-flight for human passengers and critical supplies. The current methods for interplanetary orbital transfers, such as the Hohmann transfer, require either expensive, high fuel maneuvers or extended space travel. However, by utilizing the high velocities of a super-geosynchronous space elevator, spacecraft released from an apex anchor could achieve interplanetary transfers with minimal Delta V fuel and time of flight requirements. By using Lambert’s Problem and Free Release propagation to determine the minimal fuel transfer from a terrestrial space elevator to Mars under a variety of initial conditions and time-of-flight constraints, this paper demonstrates that the use of a space elevator release can address both needs by dramatically reducing the time-of-flight and the fuel budget.
ContributorsTorla, James (Author) / Peet, Matthew (Thesis director) / Swan, Peter (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The purpose of this project is to raise awareness for children with social anxiety. As a book directed to children around the age of 12, it will give them a character they can relate to, so they can feel less alone. Throughout the story, the main character experiences symptoms of social anxiety and is subject to events that exacerbate those symptoms. Despite her challenges, the main character is able to effectively cope with her social anxiety through her own hard work, and help from her family members, teachers, and peers. The intent is to show children with social anxiety that, contrary to what their disorder makes them feel, they are special and have the capacity to develop skills that are relevant to their talents and interests, and overcome their fears. They should know that parents, teachers, and peers will be there to help and support them and will not judge them as harshly as they suspect. The supporting characters in this story show how a strong support base can influence the success of children with social anxiety. By the end of the story, the main character still has social anxiety, but has gained confidence and her symptoms are less severe. This illustrates that, although social anxiety cannot simply be overcome—that is, it doesn’t go away completely—it can be effectively managed with assistance from close others, and perseverance.
ContributorsDillard, Bethlehem (Author) / Lewis, Stephen (Thesis director) / Gaffney, Cynthia (Committee member) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This thesis evaluates the viability of an original design for a cost-effective wheel-mounted dynamometer for road vehicles. The goal is to show whether or not a device that generates torque and horsepower curves by processing accelerometer data collected at the edge of a wheel can yield results that are comparable to results obtained using a conventional chassis dynamometer. Torque curves were generated via the experimental method under a variety of circumstances and also obtained professionally by a precision engine testing company. Metrics were created to measure the precision of the experimental device's ability to consistently generate torque curves and also to compare the similarity of these curves to the professionally obtained torque curves. The results revealed that although the test device does not quite provide the same level of precision as the professional chassis dynamometer, it does create torque curves that closely resemble the chassis dynamometer torque curves and exhibit a consistency between trials comparable to the professional results, even on rough road surfaces. The results suggest that the test device provides enough accuracy and precision to satisfy the needs of most consumers interested in measuring their vehicle's engine performance but probably lacks the level of accuracy and precision needed to appeal to professionals.
ContributorsKing, Michael (Author) / Ren, Yi (Thesis director) / Spanias, Andreas (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
As climate change and air pollution continue to plague the world today, committed citizens are doing their part to minimize their environmental impact. However, financial limitations have hindered a majority of individuals from adopting clean, renewable energy such as rooftop photovoltaic solar systems. England Sustainability Consulting plans to reverse this limitation and increase affordability for residents across Northern California to install solar panel systems for their energy needs. The purpose of this proposal is to showcase a new approach to procuring solar panel system components while offering the same products needed by each customer. We will examine market data to further prove the feasibility of this business approach while remaining profitable and spread our company's vision across all of Northern California.
ContributorsEngland, Kaysey (Author) / Dooley, Kevin (Thesis director) / Keahey, Jennifer (Committee member) / Department of Supply Chain Management (Contributor) / School of Social and Behavioral Sciences (Contributor) / W.P. Carey School of Business (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This research project will test the structural properties of a 3D printed origami inspired structure and compare them with a standard honeycomb structure. The models have equal face areas, model heights, and overall volume but wall thicknesses will be different. Stress-deformation curves were developed from static loading testing. The area under these curves was used to calculate the toughness of the structures. These curves were analyzed to see which structures take more load and which deform more before fracture. Furthermore, graphs of the Stress-Strain plots were produced. Using 3-D printed parts in tough resin printed with a Stereolithography (SLA) printer, the origami inspired structure withstood a larger load, produced a larger toughness and deformed more before failure than the equivalent honeycomb structure.
ContributorsMcGregor, Alexander (Author) / Jiang, Hanqing (Thesis director) / Kingsbury, Dallas (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05