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Description
Orbiting space debris is an active issue that affects the capability of space launch for future satellites, probes, and space shuttles, and it will become a nearly insurmountable problem without action. Debris of varying sizes and speeds orbit the Earth at a range of heights above the atmosphere and need to be removed to avoid damage to crucial equipment of active orbiting satellites including the International Space Station. Finding a feasible solution to space debris removal requires that several facets be covered to become a reality; these include being aware of the problem in magnitude and source. This literature assessment covers the magnitude of space debris in low-earth and geosynchronous orbit as well as collision events which have increased the amount of space debris. There have been efforts made by several space agencies to control the amount of space debris added to orbit by current and future launches over the last decade \u2014 serving as a temporary fix before removal can be executed. This paper explores known removal efforts through mitigation, projects conceived and tested by DARPA, related space policies and laws, CubeSat technology, and the cataloguing of known space debris. To make space debris removal a reality, roadblocks need to be removed to acquire permission from states or countries for space missions. For example, these restrictions are in place to protect the assets of several countries and organizations. Guidelines set to curb the growth of space debris fail to prevent the growth due to the restrictions for ownership rights making them not as effective. This paper covers space policy and laws, the economy, satellite ownership, international conflict, status of space debris, and the overall feasibility of space debris removal. It will then discuss currently proposed solutions for the removal of space debris. Finally, this paper attempts to weight the advantages and disadvantages of the idea that space debris removal should include the opportunity to recycle materials. For example, defunct satellites and other discarded space crafts could be used for future launches. It will conclude with a personal exploration of what materials can be recycled, what chemical processes can be used to break down materials, and how to combine recycling and chemical processes for space-based recycling stations between Earth and the moon. The overall question that drives the search for making space debris removal a reality is whether it is feasible in multiple areas including technologically, legally, monetarily, and physically.
ContributorsBreden, Elizabeth Catherine (Author) / Foy, Joseph (Thesis director) / Thoesen, Andrew (Committee member) / Maximon, Leonard (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Brown adipose tissue (BAT) is thought to be important in combating obesity as it can expend energy in the form of heat, e.g. thermogenesis. The goal of this study was to study the effect of injected norepinephrine (NE) on the activation of BAT in rats that were fed a high fat diet (HFD). A dose of 0.25 mg/kg NE was used to elicit a temperature response that was measured using transponders inserted subcutaneously over the BAT and lower back and intraperitoneally to measure the core temperature. The results found that the thermic effect of the BAT increased after the transition from low fat diet to a high fat diet (LFD) yet, after prolonged exposure to the HFD, the effects resembled levels found with the LFD. This suggests that while a HFD may stimulate the effect of BAT, long term exposure may have adverse effects on BAT activity. This may be due to internal factors that will need to be examined further.
ContributorsSion, Paul William (Author) / Herman, Richard (Thesis director) / Borges, Chad (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Cystic Fibrosis (CF) is a genetic disorder that disrupts the hydration of mucous of the lungs, which promotes opportunistic bacterial infections that begin in the affected person’s childhood, and persist into adulthood. One of the bacteria that infect the CF lung is Pseudomonas aeruginosa. This gram-negative bacterium is acquired from the environment of the CF lung, changing the expression of phenotypes over the course of the infection. As P. aeruginosa infections become chronic, some phenotype changes are known to be linked with negative patient outcomes. An important exoproduct phenotype is rhamnolipid production, which is a glycolipid that P. aeruginosa produces as a surfactant for surface-mediated travel. Over time, the expression of this phenotype decreases in expression in the CF lung.
The objective of this investigation is to evaluate how environmental changes that are related to the growth environment in the CF lung alters rhamnolipid production. Thirty-five P. aeruginosa isolates from Dartmouth College and Seattle Children’s Hospital were selected to observe the impact of temperature, presence of Staphylococcus aureus metabolites, and oxygen availability on rhamnolipid production. It was found that the rhamnolipid production significantly decreased for 30C versus 37C, but not at 40C. The addition of S. aureus spent media, in any of the tested conditions, did not influence rhamnolipid production. Finally, the change in oxygen concentration from normoxia to hypoxia significantly reduced rhamnolipid production. These results were compared to swarming assay data to understand how changes in rhamnolipid production impact surface-mediated motility.
The objective of this investigation is to evaluate how environmental changes that are related to the growth environment in the CF lung alters rhamnolipid production. Thirty-five P. aeruginosa isolates from Dartmouth College and Seattle Children’s Hospital were selected to observe the impact of temperature, presence of Staphylococcus aureus metabolites, and oxygen availability on rhamnolipid production. It was found that the rhamnolipid production significantly decreased for 30C versus 37C, but not at 40C. The addition of S. aureus spent media, in any of the tested conditions, did not influence rhamnolipid production. Finally, the change in oxygen concentration from normoxia to hypoxia significantly reduced rhamnolipid production. These results were compared to swarming assay data to understand how changes in rhamnolipid production impact surface-mediated motility.
ContributorsKiermayr, Jonathan Patrick (Author) / Bean, Heather (Thesis director) / Misra, Rajeev (Committee member) / Haydel, Shelley (Committee member) / School of International Letters and Cultures (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The Beauty Within is a ceramics show displaying human body anatomy, which seeks to bridge aspects of my biological sciences major in the School of Life Sciences with aspects of my studio art minor in the Herberger Institute for Design and the Arts. My goal in creating the show was to change the opinion of people on human body organs from unease to admiration by recreating these organs in an artistic light. By stylizing the construction of the pieces and bringing in the contemporary form of art \u2014 makeup art \u2014 I hoped to bring a new light to the pieces and highlight the beauty within the human body. By leaving the pieces partly unfinished I further hoped to draw attention to the natural beauty within the pieces regardless of the makeup that covers them. By holding the show in the human anatomy lab room on campus and having both animal and human organs on display I was able to create that sense of disgust toward the organs in the viewers. The beauty of my created pieces was then directly contrasted with the disgust felt about the real organs by displaying each of my pieces next to a real organ. The reactions of the viewers reflected a change in view from the actual organs to my re-created organs, and therefore the goal of the show was achieved.
ContributorsThomas, Brandon Lee (Author) / Weiser, Kurt (Thesis director) / Chung, Samuel (Committee member) / School of Art (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The Mexican gray wolf (Canis lupus baileyi) is a genetically distinct subspecies of the gray wolf (Canis lupus) that was driven to the brink of extinction as a result of human persecution. The wolf is listed as Endangered under the Endangered Species Act, and a recovery program is underway in Arizona and New Mexico to restore its population. However, the wolf is struggling to recover due to high mortality, which is a result of continued human hostility toward it. This thesis examines historical and current human attitudes toward the wolf and the implications that they have had on the extermination and recovery of the subspecies. An overview is given of wolf biology, the history of wolf extermination and recovery, and recent events relating to the recovery of the wolf. Negative impacts on ranching, hunting, and human safety are the main reasons for opposition toward wolves and wolf recovery; these concerns are analyzed, and solutions to them are proposed, with the goal of addressing them while fostering non-lethal coexistence with the wolf. In addition, opposition to wolves and wolf recovery is tied in with larger socio-political issues and is influenced by the representation of the wolf in culture; these issues in the context of wolves are also analyzed.
ContributorsLenk, Heather Nicole (Author) / Smith, Andrew (Thesis director) / Minteer, Ben (Committee member) / Brown, David E. (Committee member) / School of Life Sciences (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Limited research has analyzed how culture might influence the utilization of social support. To address this deficiency, the present study investigated preferences for social support among East-Asian, Hispanic, and White participants. In this set of studies, a comprehensive social support taxonomy was constructed in order to better identify and conceptualize the various support subtypes found in the literature. Based on the taxonomy, a questionnaire measure for preferences of different types of social support was developed. Participants were asked to rate how helpful they would find each supportive action made by a friend or family member on a seven-point Likert scale. Based on the responses of 516 Amazon Mechanical Turk workers, a five-factor solution for an 18-item scale emerged from a factor analysis. The social support subscales supported by the factor analysis were emotional, tangible, self-referencing, reappraisal, and distraction. The questionnaire was used to assess similarities and differences among East-Asian, Hispanic, and White participants in terms of preferences for providing and receiving social support. Based on the results of 299 college-age students, an analysis of variance on individually standardized ("ipsatized") responses was conducted in order to eliminate the positioning effect of culture. A main effect of ethnicity (p=.05) and an interaction between ethnicity and sex (p=.02) were significant for the preference of tangible social support. A main effect of ethnicity (p=.04) and an interaction between ethnicity and sex (p=.05) were significant for the preference of reappraisal social support. Clinical implications of our research findings are discussed.
ContributorsCampagna, Allegra Xiu Hong (Author) / Shiota, Michelle N. (Thesis director) / Campos, Belinda (Committee member) / Yee, Claire (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
This study focused on the connection between the EnvZ/OmpR two-component regulatory system and the iron homeostasis system in Escherichia coli, specifically how a mutant form of EnvZ11/OmpR is able to reduce the expression of fepA::lacZ, a reporter gene fusion in E. coli. FepA is one of several outer membrane siderophore receptors that allow extracellular siderophores bound to iron to enter the cells to power various biological processes. Previous studies have shown that in E. coli cells that expressed a mutant allele of envZ, called envZ11, which led to altered expression of various iron genes including down regulation of fepA::lacZ. The wild type EnvZ/OmpR system is not considered to regulate iron genes, but because these envz11 strains had downregulated fepA::lacZ, this study was undertaken to understand the connection and mechanisms of this downregulation. A large number of Lac+ revertants were obtained from the B32-2483 strain (envz11 and fepA::lacZ) and 7 Lac+ revertants that had reversion mutations not directly correcting the envZ11 allele were further characterized. With P1 phage transduction genetic mapping that involved moving a kanamycin resistance marker linked to fepA::lacZ, two Lac+ revertants were found to have their reversion mutations in the fepA promoter region, while the other five revertants had their mutations mapping outside the fepA region. These two revertants underwent DNA sequencing and found to carry two different single base pair mutations in two different locations of the fepA promoter region. Each one is in the Fur repressor binding region, but one also may have affected the Shine-Dalgarno region involved in translation initiation. All 7 reveratants underwent beta-galactosidase assays to measure fepA::lacZ expression. The two revertants that had mutations in the fepA promoter region had significantly increased fepA activity, with the revertant with the Shine-Dalgarno mutation having the most elevated fepA expression. The other 5 revertants that did not map in the fepA region had fepA expression elevated to the same level as that found in the wild type EnvZ/OmpR background. The data suggest that the negative effect of envZ11 can be overcome by multiple mechanisms, including directly correcting the envZ11 allele or changing the fepA promoter region.
ContributorsKalinkin, Victor Arkady (Co-author) / Misra, Rajeev (Co-author, Thesis director) / Mason, Hugh (Committee member) / Foy, Joseph (Committee member) / Biomedical Informatics Program (Contributor) / School of Life Sciences (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
My passion on the importance of oral health began when I was four years old with the traumatic experience of witnessing my grandmother, my idol, with a toothless smile without her dentures in. At present, I have been a dental assistant for five years, and have heard of similar stories of people struggling with maintaining oral hygiene and having access to oral health care, including: family members, friends, patients, coworkers, and even Arizona State University faculty. Since the abolishment of emergency dental services in Arizona's Health Care Cost Containment System, dental related oral health care rates have jumped incrementally. In addition Arizona has created a dental desert, because dentists are not setting up their practices in the rural areas of the Valley, due to wanting to generate the most amount of income. Studies have also shown that dentists feel inept at treating ethnically diverse patients as well as patients from lower socioeconomic classes. These problems create a myriad of mental effects and physical ailments on the patient that are not limited to the oral cavity. In this paper, these issues in oral health care were studied along with their effects, including recommendations for resolutions.
ContributorsTaylor, Janine Marie (Author) / Ingram-Waters, Mary (Thesis director) / Ili, Joan (Committee member) / School for the Future of Innovation in Society (Contributor) / School of Film, Dance and Theatre (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Sex trafficking is an issue that is prevalent in the United States, including in Arizona. The Catholic Charities Diversion Program in Phoenix seeks to rehabilitate adults who have been involved in prostitution. The aim of this paper was to test three pilot interventions to address stress experienced by the program clients through three different techniques which was given in a workshop format. Cognitive Behavior Therapy (CBT), Dance Movement Therapy (DMT), and yoga and meditation are the three types of stress reduction techniques that have been studied in previous research and were pilot tested with adult sex-trafficked victims. This particular sections discusses the benefits of DMT and the results obtained after teaching sex-trafficked victims this therapy. The results of the pilot studies found that all three techniques reduced levels of stress significantly, and that they want further testing.
ContributorsKhanal, Garima (Co-author) / Somayaji, Vallari (Co-author) / Satapathy, Nikita (Co-author) / Sepowitz, Dominique Roe (Thesis director) / Graff, Sarah (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Sex trafficking is an issue that is prevalent in the United States, including in Arizona. The Catholic Charities Diversion Program in Phoenix seeks to rehabilitate adults who have been involved in prostitution. The aim of this paper was to test three pilot interventions to address stress experienced by the program clients through three different techniques that were given in workshop format. Cognitive Behavior Therapy (CBT), Dance Movement Therapy, and yoga and meditation are the three types of stress reduction techniques that have been studied in previous research and were pilot tested with adult sex trafficking victims. The results of the pilot studies and all three techniques reduced levels of stress significantly, and they warrant future testing.
ContributorsSatapathy, Nikita (Co-author) / Khanal, Garima (Co-author) / Somayaji, Vallari (Co-author) / Roe-Sepowitz, Dominique (Thesis director) / Graff, Sarah (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05