Barrett, The Honors College Thesis/Creative Project Collection
Barrett, The Honors College at Arizona State University proudly showcases the work of undergraduate honors students by sharing this collection exclusively with the ASU community.
Barrett accepts high performing, academically engaged undergraduate students and works with them in collaboration with all of the other academic units at Arizona State University. All Barrett students complete a thesis or creative project which is an opportunity to explore an intellectual interest and produce an original piece of scholarly research. The thesis or creative project is supervised and defended in front of a faculty committee. Students are able to engage with professors who are nationally recognized in their fields and committed to working with honors students. Completing a Barrett thesis or creative project is an opportunity for undergraduate honors students to contribute to the ASU academic community in a meaningful way.
Displaying 1 - 10 of 38
Description
The transition from high school to college is associated with considerable life strain for adolescents, including higher reported levels of daily stress and negative affect (NA), and alterations in stress physiology have been linked to poor health. The purpose of this thesis was to use an ecological momentary assessment design to study associations between momentary experiences of negative affect and cortisol levels in a sample of adolescents transitioning to college. I also examined the potential moderating effects of two potential vulnerability or protective factors, alone status and perceived social support from friends. Adolescents provided salivary samples and completed paper-and-pencil diary reports of socioemotional experiences and alone status five times per day for three consecutive weekdays, as well as completed self-report questionnaires on perceived social support from friends. Within-person increases in momentary negative affect were associated with momentary cortisol reactivity. Alone status significantly moderated this association such that the association between momentary negative affect and momentary cortisol levels was only significant when individuals were with others and not when they were alone. Perceived social support from friends did not significantly moderate the within-person associations between negative affect and momentary cortisol levels. The findings add to our understanding of physiological correlates of socioemotional experiences, as well as contexts in which these associations may be exaggerated or attenuated. The findings inform our understanding of potential pathways by which physiological reactivity to socioemotional experiences may affect the health of adolescents as well as how prevention efforts could reduce potential poor health outcomes associated with heightened stress reactivity.
ContributorsKomarnisky, Sydney-Paige Milan (Author) / Doane, Leah (Thesis director) / Knight, George (Committee member) / Luecken, Linda (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Department of Psychology (Contributor)
Created2014-12
Description
With microspheres growing in popularity as viable systems for targeted drug therapeutics, there exist a host of diseases and pathology induced side effects which could be treated with poly(lactic-co-glycolic acid) [PLGA] microparticle systems [6,10,12]. While PLGA systems are already applied in a wide variety the clinical setting [11], microparticles still have some way to go before they are viable systems for drug delivery. One of the main reasons for this is a lack of fabrication processes and systems which produce monodisperse particles while also being feasible for industrialization [10]. This honors thesis investigates various microparticle fabrication techniques \u2014 two using mechanical agitation and one using fluid dynamics \u2014 with the long term goal of incorporating norepinephrine and adenosine into the particles for metabolic stimulatory purposes. It was found that mechanical agitation processes lead to large values for dispersity and the polydispersity index while fluid dynamics methods have the potential to create more uniform and predictable outcomes. The research concludes by needing further investigation into methods and prototype systems involving fluid dynamics methods; however, these systems yield promising results for fabricating monodisperse particles which have the potential to encapsulate a wide variety of therapeutic drugs.
ContributorsRiley, Levi Louis (Author) / Vernon, Brent (Thesis director) / VanAuker, Michael (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
With an increased demand for more enzyme-sensitive, bioresorbable and more biodegradable polymers, various studies of copolymers have been developed. Polymers are widely used in various applications of biomedical engineering such as in tissue engineering, drug delivery and wound healing. Depending on the conditions in which polymers are used, they are modified to accommodate a specific need. For instance, polymers used in drug delivery are more efficient if they are biodegradable. This ensures that the delivery system does not remain in the body after releasing the drug. It is therefore crucial that the polymer used in the drug system possess biodegradable properties. Such modification can be done in different ways including the use of peptides to make copolymers that will degrade in the presence of enzymes. In this work, we studied the effect of a polypeptide GAPGLL on the polymer NIPAAm and compare with the previously studied Poly(NIPAAm-co-GAPGLF). Both copolymers Poly(NIPAAm-co-GAPGLL) were first synthesized from Poly(NIPAAm-co-NASI) through nucleophilic substitution by the two peptides. The synthesis of these copolymers was confirmed by 1H NMR spectra and through cloud point measurement, the corresponding LCST was determined. Both copolymers were degraded by collagenase enzyme at 25 ° C and their 1H NMR spectra confirmed this process. Both copolymers were cleaved by collagenase, leading to an increase in solubility which yielded a higher LCST compared to before enzyme degradation. Future studies will focus on evaluating other peptides and also using other techniques such as Differential Scanning Microcalorimetry (DSC) to better observe the LCST behavior. Moreover, enzyme kinetics studies is also crucial to evaluate how fast the enzyme degrades each of the copolymers.
ContributorsUwiringiyimana, Mahoro Marie Chantal (Author) / Vernon, Brent (Thesis director) / Nikkhah, Mehdi (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This report provides information concerning qualities of methylcellulose and how those properties affect further experimentation within the biomedical world. Utilizing the compound’s biocompatibility many issues, ranging from surgical to cosmetic, can be solved. As of recent, studies indicate, methylcellulose has been used as a physically cross-linked gel, which cannot sustain a solid form within the body. Therefore, this report will ultimately explore the means of creating a non-degradable, injectable, chemically cross-linking methylcellulose- based hydrogel. Methylcellulose will be evaluated and altered in experiments conducted within this report and a chemical cross-linker, developed from Jeffamine ED 2003 (O,O′-Bis(2-aminopropyl) polypropylene glycol-block-polyethylene glycol-block-polypropylene glycol), will be created. Experimentation with these elements is outlined here, and will ultimately prompt future revisions and analysis.
ContributorsBundalo, Zoran Luka (Author) / Vernon, Brent (Thesis director) / LaBelle, Jeffrey (Committee member) / Overstreet, Derek (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2013-05
Description
Cerebral aneurysms, also known as intracranial aneurysms, are sac-like lesions in the arteries of the brain that can rupture to cause subarachnoid hemorrhaging, damaging and killing brain cells. Metal coil embolization has been traditionally used to occlude and treat cerebral aneurysms to limited success, but polymer embolization has been suggested, because it can provide a greater fraction of occlusion. One such polymer with low cytotoxicity is poly(propylene glycol)diacrylate (PPODA) crosslinked via Michael-type addition with pentaerythritol tetrakis(3-mercaptopropionate) (QT). This study was performed to examine the behavior of PPODA-QT gel in vitro under pulsatile flow emulating physiological conditions. An idealized cerebral aneurysm flow model was designed based on geometries associated with an increase in rupture risk. Pressure was monitored at the apex of the aneurysm dome for varied flow rates and polymer filling fractions of 32.4, 78.2, and 100%. The results indicate that the amount of PPODA-QT deployed into the aneurysm decreases the peak-to-peak oscillation in pressure at the aneurysm wall by an inverse proportion. The 32.4 and 78.2% treatments did not significantly decrease the mean pressure applied to the aneurysm dome, but the 100% treatment greatly reduced it by diverting flow. This study indicates that the maximum filling fraction after swelling of PPODA-QT polymer should be deployed into the aneurysmal sac for treatment.
ContributorsWorkman, Christopher David (Author) / Vernon, Brent (Thesis director) / Frakes, David (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Biofilm derived orthopedic infections are increasingly common after contamination of an open bone fracture or the surgical site pre- and post-orthopedic prosthetic insertion or removal. These infections are usually difficult to eradicate due to the resistant nature of biofilms to antimicrobial therapy. Difficulty of treatment of biofilm derived infections is also partly due to the presence of persister cells in the biofilm matrix. Persister cells are tolerant to antimicrobial therapy delivered via the systemic route. It is thus possible for these cells to repopulate their environment once systemic antimicrobial delivery is discontinued. The antimicrobial concentration required to eradicate bacterial biofilms, minimum biofilm eradication concentration (MBEC), can be determined in vitro by exposing biofilms to different regimens of antimicrobial solutions. Previous studies have demonstrated that values of the MBEC vary depending on the material and surface the biofilm grows on. This study investigated the relationship between antimicrobial susceptibility and antimicrobial exposure time, and the effects of surface material type on the antimicrobial susceptibility of staphylococcal biofilms. It was concluded that antimicrobial susceptibility increases with increased antimicrobial exposure time, and that the investigated surface and material properties did not have an effect on the susceptibility of staphylococcal biofilms to antimicrobial therapy. Further investigation is however necessary to confirm these results due to some inconsistent data obtained over the course of the trials.
ContributorsTavaziva, Gamuchirai Clinton (Author) / Vernon, Brent (Thesis director) / Overstreet, Derek (Committee member) / Castaneda, Paulo (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Research has shown that environmental stressors that occur during childhood and early adolescence are associated with multiple deficits in physiological and psychological functioning later in life. The hypothalamic-pituitary-adrenal (HPA) axis has been proposed as a potential biological mechanism through which these phenotypic alterations occur as studies have shown a link between early life adversity and altered diurnal cortisol patterns (Goldman-Mellor, Hamer, & Steptoe, 2012; Gunnar & Quevedo, 2008). Given research has shown that diurnal cortisol levels are influenced by genetic factors (Veen et al., 2011), but that a majority of differences across subjects can be attributed to the environment (Schreiber et al., 2006), phenotypic associations were explored between the quality of the home environment and children's diurnal cortisol patterns. The first aim of this study was to determine the level of genetic and environmental contributions to different parameters of diurnal cortisol rhythm. The second aim of this study was to examine whether the quality of the home environment, particularly indicators involving parenting and the physical environment, was associated with these same diurnal cortisol measures. A diverse sample of 320 twin children were assessed at 8 years using gold standard home environment interviews and a measure of diurnal cortisol rhythm across three days with three samples taken from each twin every day. Twin intraclass correlations indicated high levels of heritability for the morning to afternoon diurnal cortisol slope as well as the afternoon to evening slope, while measures of cortisol in the afternoon, evening, and across the day showed low levels of heritability, which suggested that differences in the environment were a more influential factor. Multilevel regression analyses showed that the overall quality of the home environment was found to be significantly negatively associated with cortisol levels at bedtime and negatively associated across the morning to afternoon slope at a trend level. The physical environment and emotional climate of the home were not significantly associated with any indicators of the diurnal cortisol pattern. A unique seasonality effect was noted as cortisol measurements taken from participants during the summer were significantly increased when compared to participants throughout the rest of the year. Overall, these findings showed a unique association between the quality of the home environment and diurnal cortisol levels at bedtime and perhaps the change in cortisol levels across the morning to afternoon, as well as a possible seasonal covariate which may affect diurnal cortisol measurements and one which often goes overlooked in cortisol research.
ContributorsSmith, Trevor James (Author) / Doane, Leah (Thesis director) / Lemery-Chalfant, Kathryn (Committee member) / School of Molecular Sciences (Contributor) / Arizona State University. College of Nursing & Healthcare Innovation (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Cultural beliefs and behaviors can serve as both risk and protective processes for Latino adolescents, with some recent empirical work suggesting the important protective role of bicultural values (e.g., endorsing high levels of both mainstream culture and culture of origin). We expanded on past research to explore whether bicultural values were associated with internalizing (depressive, anxiety, stress) symptoms and externalizing (alcohol use) symptoms among a sample of Latino adolescents preparing to begin college. We hypothesized biculturalism to protect against all negative outcomes. Our sample consisted of 209 college-bound Latino adolescents (65% female; 85.1% Mexican descent; 10.6% 1st generation, 62% 2nd generation) who were enrolled in university for the coming fall. All multivariate models included sex, ethnicity, parent education, and immigrant generation status as covariates. Correlations and multivariate analyses revealed that higher bicultural values were associated with lower depressive symptoms, lower anxiety symptoms, lower stress, and greater alcohol use. Gender was shown to moderate the relationship between biculturalism and alcohol use. Overall, findings suggested that greater bicultural values were associated with lower endorsement of internalizing symptoms for all participants, but higher endorsement of alcohol use over the last year for the highly bicultural females. Biculturalism may be particularly protective for Latino adolescents who are preparing to attend college given the need for them to transition into an environment with high acculturative demands. However, our results also highlight that these bicultural females may be at greater risk for alcohol use and related problems.
ContributorsDilgert, Janice (Author) / Doane, Leah (Thesis director) / Thompson, Daisy (Committee member) / Department of Psychology (Contributor) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
The objective of the current study was to examine sleep and academic functioning during middle childhood. More specifically, the twin design was used to determine the heritability of academic competence and sleep. Phenotypic analyses using multi-level mixed model regressions were performed to predict academic functioning from sleep. Lastly, socioeconomic status was tested as a moderator in the associations between sleep and academic functioning. Participants included twins (N = 191 families; Mage = 8.47 years) recruited from Arizona birth records at 12 months of age. Sleep duration, latency, onset, efficiency, variability, and sleep problems were assessed using actigraph watches and the Child Sleep Habits Questionnaire. Academic functioning was assessed using subtests of the Woodcock Johnson Cognitive Test of Achievement-IV (picture vocabulary, passage comprehension, and applied problems) and the MacArthur Health and Behavior Questionnaire. As determined by twin intraclass correlations, the heritability of academic competence ranged from 51-76%. Sleep heritability ranged from 14-80%. In addition, phenotypic analyses only showed a significant association between sleep latency and WJ picture vocabulary scores. More specifically, sleep latency was negatively associated with the picture vocabulary subtest. Additional models were run to examine if any interactive effects were present between early SES and the various sleep parameters. Several significant associations were observed with applied problems scores and parent-reported academic competence. Specifically, for children of low SES, a significant positive association was observed for sleep duration and WJ applied problems scores, as well as for sleep efficiency and WJ applied problems scores. No significant associations were observed for sleep efficiency and HBQ scores with children of any SES. Also, no significant relationships were observed with children of high SES for any of the academic measures.
ContributorsVakulskas, Emily (Author) / Doane, Leah (Thesis director) / Lemery-Chalfant, Kathryn (Committee member) / Breitenstein, Reagan (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Higher education institutions have increasingly sought to diversify the ethnic makeup of freshmen classes (Covarrubias, Herrmann, & Fryberg, 2016) and rates of Latinx college attendance have been rising (Hall, Nishina, & Lewis, 2017). However, despite comparable levels of earned-credits, Latinx students have lower rates of college completion (Contreras & Contreras, 2015). One potential explanation may be disproportionate increases in stress, and in particular, discrimination experiences reported by Latinx students during the transition from high school to college (Hunyh & Fuligni, 2012). As such, the aim of the current study was to examine whether everyday discrimination in high school and college were associated with changes in adolescent well-being and academic adjustment over the college transition in a sample of Latinx adolescents. Study participants were 209 Latinx adolescents (85.1% Mexican descent, 62.1% 2nd generation; 35.6% male; Mage= 17.59) who completed questionnaire assessments during the spring or summer before entering college (T1) and again during the first semester of college (T2; 88.5% retention). In both high school and college, participants completed a modified version of the Everyday Discrimination Scale (T1 α=.88, T2 α=.89; Williams et al., 1997). Dependent variables included internalizing symptoms in college (depressive symptoms {α = .95}, anxiety symptoms {α = .88}, stress symptoms {α = .94}; DASS; Lovibond & Lovibond, 1995), and institutional records of college GPA. Correlation and regression analyses were conducted in SPSS 23 to examine associations between discrimination experiences (high school and college) and college internalizing symptoms and GPA, controlling for high school levels. Other covariates included immigrant generation status, sex, parent education (as a proxy for socioeconomic status), and whether the participant attended the focal higher education institution. Zero order correlations (Table 1) revealed that greater reports of discrimination in high school and college were associated with higher depressive symptoms, higher anxiety symptoms, higher stress, but not GPA in college (Table 1; all ps <.05). In multivariate analyses and after adjusting for covariates similar patterns emerged (Table 2). Greater reports of discrimination in college were associated with higher depressive symptoms (β = .18, p < .05), anxiety symptoms (β = .19, p <.05) and stress (β = .18, p <.05), but not GPA (β = -.04, ns). Everyday experiences of discrimination in high school were not significantly associated with college outcomes. In summary, our findings suggest that discrimination experiences among Latinx students in college, but not high school, are associated with increases in internalizing symptoms, including depression, anxiety and stress. Interestingly, discrimination experiences in high school and college were not associated with academic achievement in the first semester of college. Such findings suggest that higher education institutions should focus on global indicators of well-being during the Latinx college transition and seek to implement programs to: a) reduce stress associated with engaging in diverse college environments and b) reduce discrimination experiences on college campuses. Future research is needed for replication of these results and should also seek to further explore the trajectories of internalizing symptoms beyond the first semester of college.
ContributorsSills, Jessica (Author) / Doane, Leah (Thesis director) / Perez, Marisol (Committee member) / Castro, Saul (Committee member) / Department of English (Contributor, Contributor) / Department of Psychology (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05