Matching Items (123)
Description
Fruit flies show a strong attraction to fruit odors. Most fruit odors, including strawberry scent, are complex multimolecular mixtures comprised of many chemically distinct constituents. How animals are able to process these mixtures and derive behaviorally relevant information is largely unknown. A new procedure was created to test odor preference for Heisenberg canton-s strain of Drosophila melanogaster. 30 flies were cold anesthetized at 4.2°C for 30 minutes and then placed in a testing arena. After acclimating for 45 minutes, the flies were exposed to two sources of air, one with ripe strawberry odor and one with only humidified air. Images were captured every minute for an hour and a preference index was calculated for every 10th image. The Drosophila had a positive average preference for the strawberry odor. Five out of six trials showed a general increase in odor preference over the course of the trial. While there was a generally positive trend for average preference over time, there was not a significant increase in average odor preference from time 1 to time 60. The data indicates that Drosophila show a preference for strawberry odor over humidified air, and we propose to extend this test to investigate how Drosophila process and react to complex odors and their chemical constituents.
ContributorsSteinmetz, Kyle J (Author) / Smith, Brian (Thesis director) / Jernigan, Chris (Committee member) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Recent data suggests that olfactory input is important for antennal lobe development in honey bees. Chronic association of a single odor to food resources during crucial stages of development results in delayed antennal lobe development for mature foraging bees. The antennal lobes of these bees instead closely resemble an immature network observed in young, newly emerged bees. Using an odor stimuli variance assay, learning and memory tests can be used to explore how well honey bees discriminate single odors within complex odor mixtures. Here we are validating two different odor mixtures, a Brassica rapa floral blend and a second replicate mixture composed of common molecularly dissimilar odors. Odors in each mixture are either held constant or varied in concentration over 16 conditioning trials. Subsequent memory tests are performed two hours later to observe the ability of bees to distinguish and recognize specific odor components in each mixture. So far in our assay we find high rates of generalization for both odor mixtures. In general, more bees responded to all odors in the replicate treatment group over the Brassica treatment group. Additionally, bees in the Brassica treatment group did not respond to the target odor. More data is being collected to validate this assay. In future studies, I propose to apply this behavioral assay to bees with an altered olfactory developmental in order to see the functional impacts of this chronic odor association treatment.
ContributorsHalby, Rachael (Author) / Smith, Brian (Thesis director) / Jernigan, Christopher (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Asperger's syndrome is a high-functioning subset of Autism Spectrum Disorders (ASD). Diagnosed patients often lack refined social skills but possess a normal level of cognitive skills without delay in language development. These deficient social skills can impact the ability to find and maintain a job, which can be burdensome for all individuals involved in the patient's life. Although the causes of this condition are largely unknown, a wide variety of social and cognitive therapies have been used to reduce symptom severity, one of which is Mindfulness-Based Stress Reduction (MBSR). Mindfulness is the act of being aware on purpose to whatever is being experienced in the present moment with non-judgment and receptivity. MBSR has been used to bring greater awareness to sensations, thoughts and emotions with the result being reduced reactivity and increased purposeful responsiveness. It is therefore the aim of this study to address the use of an 8-week Mindfulness-Based Stress Reduction in adolescents with clinical Asperger's Syndrome to reduce reactive tendencies. This study will utilize a randomized control group of waitlisted participants given MBSR informational material and a practicing MBSR group. Post-MBSR Parent Global Impressions-III (PGI-III) and Social Responsiveness Scale scores are hypothesized to be improved in MBSR group and unaffected in the control for behavioral markers with no change in core autistic symptoms. Daily average cortisol response is also expected to decrease in the experimental group with unaffected levels in the control.
ContributorsBrzezinski, Molly Alexandra (Author) / Smith, Brian (Thesis director) / Sebren, Ann (Committee member) / School of Music (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The mammalian olfactory system is commonly studied by using the mouse as a model system. Odor habituation is used to investigate odor perception and learning processes. Most previous experimental preparations have been tedious, requiring a researcher to manually change odorants, record investigation time and duration at each odorant, or physical alteration on the mice to enable video tracking. These limitations were overcame by creating an odorized hole-board to allow for systematic and automatic recording of olfactory behavior in mice. A cohort of five male mice were utilized in these experiments and the responses to the odor of strawberries, a diet staple of wile mice, were examined. Experiment 1 showed that free-feeding mice exhibit a preference to locations with strawberry (over control locations), even when these locations can only be identified using olfaction. This preference habituates within a trial but not across days. Experiment 2 showed that strawberry odor without reward causes habituation or extinction to the odor both within trials and across days. From these experiments, it can be concluded that mice innately explore strawberry odor and this can be exploited to the study odor habituation using an odorized hole-board.
ContributorsMa, Jason (Author) / Smith, Brian (Thesis director) / Gerkin, Richard (Committee member) / Oddo, Salvatore (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Animals must learn to ignore stimuli that are irrelevant to survival, a process referred to as latent inhibition. The Amtyr1 gene has been shown through quantitative trait loci mapping to be linked to strong latent inhibition in honey bees. Here we implicate this G-protein coupled receptor for the biogenic amine tyramine as an important factor underlying this form of learning in honey bees. We show that dsRNA targeted to disrupt the tyramine receptors, specifically affects latent inhibition but not excitatory associative conditioning. Our results therefore identify a distinct reinforcement pathway for latent inhibition in insects.
ContributorsPetersen, Mary Margaret (Author) / Smith, Brian (Thesis director) / Wang, Ying (Committee member) / Sinakevitch, Irina (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
In injection molded plastic parts, knit lines occur where opposing streams of material fuse together while the mold cavity fills. When parts with knit lines experience external loading, the knit lines cause areas of mechanical weakness. This weakness is especially drastic in fiber-reinforced polymers due to an unfavorable orientation of fibers at the knit line. A possible way to reduce the impact of knit lines is to incorporate overflow tabs into the mold design. An overflow tab is a chamber attached to the mold cavity that provides an extra space for the end of material flow to occur. Research shows that overflow tabs improve the fiber orientation at the knit line, resulting in increased mechanical strength. The goal of this study is to utilize overflow tabs to optimize the knit line strength of nylon 6-6 that is 30% carbon fiber reinforced. In this project, an initial overflow tab is first designed. Then four modifications are made to the tab design, each altering a separate variable while holding the others constant. The design changes explored for the tab in this project include adding radii to the inlet, shifting the inlet location, increasing the inlet cross-sectional area by 50%, and increasing the tab chamber volume by 50%. Specimens were molded using the initial tab design and the modified tab designs. Testing for this experiment consists of three specimens of each type for three-point bending tests, and five specimens of each type for tensile tests. The material properties analyzed are the flexural modulus, flexural strength, tensile modulus, and tensile strength. From the testing, the tab with the 50% increased volume consistently yielded the highest results and showed large improvement from the initial tab design. However, the other three tab modifications either showed negative change or slight improvement from the initial tab design. Based on the results of this study, the overflow tab volume is the most beneficial design parameter to adjust.
ContributorsJones, Justin Michael (Author) / Adams, James (Thesis director) / Wamsley, Steven (Committee member) / Computer Science and Engineering Program (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The purpose of this honors project is to analyze the difference between different powder separation techniques, and their suitability for my capstone project – ‘Effect of Powder Reuse on DMLS (Direct Metal Laser Sintering) Product Integrity’. Due to the nature of my capstone project, my group needs to characterize foreign contaminants in IN 718 (Ni-based superalloy) powder with a mean diameter around 40um. In order to clearly analyze the contaminants and recycle useful IN 718 powders, powder separation is favorable since the filtered samples will be much easier to characterize rather than inspect all the powders at once under microscope. By conducting literature review, I found that powder separation is commonly used in Geology, and Chemistry department. To screen which combination of techniques could be the best for my project, I have consulted several research specialists, obtained adequate knowledge about powder separation. Accordingly, I will summarize the pros and cons of each method with regard the specific project that I am working on, and further explore the impacts of each method under economical, societal, and environmental considerations. Several powder separation techniques will be discussed in details in the following sections, including water elutriation, settling column, magnetic separation and centrifugation. In addition to these methods, sieving, water tabling and panning will be briefly introduced. After detailed comparison, I found that water elutriation is the most efficient way to purity IN718 powder for reuse purpose, and recovery rate is as high as 70%, which could result in a significant reduction in the manufacturing cost for Honeywell since currently Honeywell only use virgin powders to build parts, and 90% of the leftover powders are discarded.
ContributorsLuo, Zheyu (Author) / Adams, James (Thesis director) / Tasooji, Amaneh (Committee member) / Materials Science and Engineering Program (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Honeywell is currently extending the reach of additive manufacturing (AM) in its product line and expects to produce as much as 40% of its inventory through AM in five years. Additive manufacturing itself is expected to grow into a $3.1 billion dollar industry in the next 5 to 10 years. Reusing IN 718 powder, a nickel-based super alloy metal powder, is an ideal option to reduce costs as well as reduce waste because it can be used with additive manufacturing, but the main obstacles are lack of procedure standardization and product quality assurances from this process. The goal of the capstone project, "Effect of Powder Reuse on DMLS (Direct Metal Laser Sintering) Product Integrity," is to create a powder characterization protocol in order to determine if the IN 718 powder can be reused and what effect the IN 718 reused powder has on the mechanical properties of the products Honeywell fabricates. To provide context and impact of this capstone project, this paper serves to identify the benefits of AM for Honeywell and the cost effectiveness of reusing the powder versus using virgin powder every time. It was found that Honeywell's investment in AM is due to the cost effectiveness of AM, versatility in product design, and to ensure Honeywell remains competitive in the future. In terms of reducing expenses, reusing powder enables costs to be approximately 45% less than using virgin powder. With these key pieces of information, the motivations for this capstone project are understood to a fuller and more profound degree.
ContributorsQuigley, Elizabeth (Co-author) / Luo, Zheyu (Co-author) / Murella, Anoosha (Co-author) / Lee, Wey Lyn (Co-author) / Adams, James (Thesis director) / Tasooji, Amaneh (Committee member) / Materials Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Autism Spectrum Disorder is a disorder that makes learning, socializing and daily living much more challenging for affected children and adults because of their atypical behaviors. A few examples of these behaviors are repetitive movements, impulsive actions, inability to communicate in a social setting, and many more. There is a stigma behind autism that is caused by those who are not well informed on the disorder. These people lack information, and in the past, it was assumed that the disorder is caused by "bad parenting." The parents are then afraid of social shame brought upon them by their child and neglect or avoid a diagnosis for their child's disorder. This becomes a vicious cycle that has negative effects on the affected individuals and their loved ones. Neglect of a diagnosis may also be caused by misinformation interpreted by the parents as their child develops. The parents do not realize this child developing outside of normal behavioral patterns. Years of research have been done to attempt to alleviate the symptoms of autism and cure the disorder. The Autism and Asperger's Program at ASU has developed a year-long dietary plan that increases supplementation to alleviate nutritional deficiencies in participants with autism. These deficiencies include vitamins, minerals, essential fatty acids, sulfate, carnitine, and digestive enzymes such as sucrase, maltase, and lactase. The participants were also put on a gluten-free casein-free diet toward the end of the study. To test the effectiveness of the treatment, the Severity of Autism Scale (SAS) and Social Responsiveness Scales (SRS) were used. The SAS tested the overall severity of ASD participants by rating them from one to ten, ten being "very severe" in terms of ASD symptoms. The results of this scale were compared at the beginning of the study (day 0) and at the end of the study (day 365). The SRS tested the social responsiveness of participants in the form of overall SRS and five subscales that included awareness, cognition, communication, motivation, and mannerisms. These results were also compared at the beginning and end of the study. After analysis of the data, there seemed to be no correlation between age and severity of autism/social responsiveness of participants. There was also no statistically significant data to suggest that there was a correlation between gender and severity of autism/social responsiveness of participants. However, there was statistically significant evidence that the treatment group did improve over the non-treatment/delayed treatment group in both the SAS and SRS. Neither age nor gender had a significant effect on the effectiveness of the treatment. These positive findings suggest that the integrated dietary
utritional therapy was beneficial, and future research on dietary treatments for autism and other disorders is recommended. This may also further discoveries of affected epigenomes with regards to nutritional treatments in disorders like ASD. The epigenome is the methylation and demethylation of the genome that mediates gene expression.
utritional therapy was beneficial, and future research on dietary treatments for autism and other disorders is recommended. This may also further discoveries of affected epigenomes with regards to nutritional treatments in disorders like ASD. The epigenome is the methylation and demethylation of the genome that mediates gene expression.
ContributorsGutgsell, Crystal Megan (Author) / Adams, James (Thesis director) / Pollard, Elena (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
A novel approach, the Invariant Based Theory of Composites and the "Trace" method it proposes, has the potential to reduce aerospace composite development times and costs by over 30% thus reinvigorating the development process and encouraging composite technology growth. The "trace" method takes advantage of inherent stiffness properties of laminates, specifically carbon fiber, to make predictions of material properties used to derive design allowables. The advantages of the "trace" theory may not necessarily be specific to the aerospace industry, however many automotive manufacturers are facing environmental, social and political pressure to increase the gas mileage in their vehicles and reduce their carbon footprint. Therefore, the use of lighter materials, such as carbon fiber composites, to replace heavier metals in cars is inevitable yet as of now few auto manufacturers implement composites in their cars. The high material, testing and development costs, much like the aerospace industry, have been prohibitive to widespread use of these materials but progress is being made in overcoming those challenges. The "trace" method, while initially intended for quasi-isotropic, aerospace grade carbon-fiber laminates, still yields reasonable, and correctable, results for types of laminates as well such as with woven fabrics and thermoplastic matrices, much of which are being used in these early stages of automotive composite development. Despite the varying use of materials, the "trace" method could potentially boost automotive composites in a similar way to the aerospace industry by reducing testing time and costs and perhaps even playing a role in establishing emerging simulations of these materials.
ContributorsBrown, William Ross (Author) / Adams, James (Thesis director) / Anwar, Shahriar (Committee member) / Krause, Stephen (Committee member) / Materials Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05