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.
Much of Nepal lacks access to clean drinking water, and many water sources are contaminated with arsenic at concentrations above both World Health Organization and local Nepalese guidelines. While many water treatment technologies exist, it is necessary to identify those that are easily implementable in developing areas. One simple treatment that has gained popularity is biochar—a porous, carbon-based substance produced through pyrolysis of biomass in an oxygen-free environment. Arizona State University’s Engineering Projects in Community Service (EPICS) has partnered with communities in Nepal in an attempt to increase biochar production in the area, as it has several valuable applications including water treatment. Biochar’s arsenic adsorption capability will be investigated in this project with the goal of using the biochar that Nepalese communities produce to remove water contaminants. It has been found in scientific literature that biochar is effective in removing heavy metal contaminants from water with the addition of iron through surface activation. Thus, the specific goal of this research was to compare the arsenic adsorption disparity between raw biochar and iron-impregnated biochar. It was hypothesized that after numerous bed volumes pass through a water treatment column, iron from the source water will accumulate on the surface of raw biochar, mimicking the intentionally iron-impregnated biochar and further increasing contaminant uptake. It is thus an additional goal of this project to compare biochar loaded with iron through an iron-spiked water column and biochar impregnated with iron through surface oxidation. For this investigation, the biochar was crushed and sieved to a size between 90 and 100 micrometers. Two samples were prepared: raw biochar and oxidized biochar. The oxidized biochar was impregnated with iron through surface oxidation with potassium permanganate and iron loading. Then, X-ray fluorescence was used to compare the composition of the oxidized biochar with its raw counterpart, indicating approximately 0.5% iron in the raw and 1% iron in the oxidized biochar. The biochar samples were then added to batches of arsenic-spiked water at iron to arsenic concentration ratios of 20 mg/L:1 mg/L and 50 mg/L:1 mg/L to determine adsorption efficiency. Inductively coupled plasma mass spectrometry (ICP-MS) analysis indicated an 86% removal of arsenic using a 50:1 ratio of iron to arsenic (1.25 g biochar required in 40 mL solution), and 75% removal with a 20:1 ratio (0.5 g biochar required in 40 mL solution). Additional samples were then inserted into a column process apparatus for further adsorption analysis. Again, ICP-MS analysis was performed and the results showed that while both raw and treated biochars were capable of adsorbing arsenic, they were exhausted after less than 70 bed volumes (234 mL), with raw biochar lasting 60 bed volumes (201 mL) and oxidized about 70 bed volumes (234 mL). Further research should be conducted to investigate more affordable and less laboratory-intensive processes to prepare biochar for water treatment.
Heron Lodge is the hybrid product of sciences, (pre) medicine, and the humanities throughout four years of an undergraduate degree in Medical Studies.
Executive functioning (EF) is the cognitive processing of goal-oriented actions that are predictive of important life functioning skills. Middle childhood is an important time for academic achievement and social development. Positive and negative parenting practices were examined in the prediction of several child executive functioning outcomes in middle childhood, this thesis further examined whether early life socioeconomic status moderated such associations. This sample consisted of 708 twins (32% monozygotic, 36% same-sex dizygotic, and 32% opposite-sex dizygotic) with ethnically and socioeconomically diverse backgrounds at two age points, 12 months old (M = 12.5 months, SD = 1.06) and 8 years old (M = 8.41, SD = .40).There was a significant negative main effect between negative parenting and CPT. Further, positive parenting interacted with SES to predict CPT and Digit Span Forward. A significant positive effect was identified between positive parenting and CPT in low SES families, but not high SES families. Interestingly, greater positive parenting was associated with lower Digit Span Forward in high SES families, but not low SES families. These findings suggest that while negative parenting was associated with worse EF across the entire sample, the relationship between positive parenting practices and executive functioning outcomes differed based on early life socioeconomic status. Future research should examine whether various domains of executive functioning may follow different developmental patterns.
Participants were 475 twins and their primary caregivers (mean age=8.48; Primary caregivers: 64% White, 36% Hispanic; 53.8% middle class or above). I found no main effects between parental cultural values and child cortisol outcomes and no main effects between parenting behaviors and child cortisol outcomes. However, when exploring the moderating role of race/ethnicity, it was found that, as compared to children of White primary caregivers, children of Hispanic primary caregivers who had higher levels of parental authoritarianism had steeper PM slopes, indicating more adaptive cortisol outcomes. This suggests that the adaptiveness of certain parenting behaviors may differ across racial/ethnic groups such that what is considered to be “good parenting” may not translate across differing racial/ethnic groups. Ultimately, further research should be conducted in order to further explore the impact of race/ethnicity in the outcomes of our children.
