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- Creators: School of Molecular Sciences
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Description
Isotopic analyses of archaeological and modern materials are commonly used to reconstruct diet, climate, and habitat. This study analyzes 15 camelid samples from three sites (two archaeological, one modern) in South America to determine their carbon and nitrogen isotopic values to further explore the relationship between stable isotopes and environments. Camelid individuals in the modern site of Cuenca, Ecuador had a diet of almost entirely C3 vegetation, while those in Chen Chen, Peru had slightly higher values, still consistent with C3 plants. Those in the higher altitude site of Pumapunku, Bolivia had higher δ13C values than expected, indicating they may have been foddered with a mixed diet. These isotopic data indicate that vegetation, and therefore herbivore diets, are influenced by altitude. Additionally, it was found that a positive linear relationship exists between δ15N values and aridity of a site. Results indicate that aspects of the environment such as aridity are reflected in isotopic signatures. These results contribute to the increasing amount of data on isotopic variation in South American camelids, both modern and archaeological.
ContributorsSpencer, Katherine Clare (Author) / Knudson, Kelly (Thesis director) / Reed, Kaye (Committee member) / School of Human Evolution and Social Change (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
In our modern world the source of for many chemicals is to acquire and refine oil. This process is becoming an expensive to the environment and to human health. Alternative processes for acquiring the final product have been developed but still need work. One product that is valuable is butanol. The normal process for butanol production is very intensive but there is a method to produce butanol from bacteria. This process is better because it is more environmentally safe than using oil. One problem however is that when the bacteria produce too much butanol it reaches the toxicity limit and stops the production of butanol. In order to keep butanol from reaching the toxicity limit an adsorbent is used to remove the butanol without harming the bacteria. The adsorbent is a mesoporous carbon powder that allows the butanol to be adsorbed on it. This thesis explores different designs for a magnetic separation process to extract the carbon powder from the culture.
ContributorsChabra, Rohin (Author) / Nielsen, David (Thesis director) / Torres, Cesar (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2015-05
Description
This project was generated out of a desire to understand and explore a novel twist on a well-traversed route to happiness. I set out looking for a new perspective on fulfillment and found sustainable, everyday joy through gratitude. In doing so, I created a space where a group of people could practice and share gratitude as a community. Gratitude is familiar to most as a feeling, but putting intention behind gratitude turns it into an action, and even a virtue. In fact, Roman philosopher Cicero says, "Gratitude is not only the greatest of virtues, but the parent of all others." I created a Facebook community called Marvel at The Ordinary (MATO) applying principles rooted in the Theory of Change to express this greatest virtue. I found both success and earnest support from others in this novel approach to current gratitude practices. Defined by Dr. Robert Emmons, an expert in the science of gratitude, practicing gratitude is a two-step process: "(1.) affirming goodness in one's life, and (2.) recognizing that the sources of this goodness lie at least partially outside of the self." There is substantial research touting the worth of gratitude journaling, in fact, few things have been more repeatedly and empirically vetted than the connection between gratitude and overall happiness and well-being. Yet there is one facet ubiquitously overlooked in current gratitude research: what happens when gratitude journaling is shared with others? With anecdotal evidence, short-form interview analysis, thematic analysis of journaling lexicon, and a case study on the growth and engagement of Marvel at The Ordinary as a social movement, there is reason to believe that a social media-based community centered around gratitude may support and even enhance the practice of gratitude, which is typically practiced in isolation. It was also found that communities of this sort are highly sought after, based on the engagement within and growth of the Facebook group from 50 to 600+ members in a period of 2 months. MATO set out with the aspirations of creating a community which encourages others to gratitude journal, raising awareness about gratitude journaling, and building a community which fosters empathy, optimism, and awareness in an everyday sense. In each of these goals, overwhelming success was found.
ContributorsMccawley, Kevin William (Author) / Mokwa, Michael (Thesis director) / Huerta, Mark (Committee member) / Micevic, Vid (Committee member) / School of International Letters and Cultures (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Metalloporphyrins serve important roles in biological processes and in emerging technologies with applications to energy conversion. When electrochemically activated in solution, metalloporphyrins have the ability to catalyze the conversion of protons into hydrogen fuels. In this report, the synthesis and characterization of zinc, nickel, cobalt and copper analogs of 5,10,15,20-tetrakis(pentafluorophenyl) porphyrin (PF20) and 5,10,15,20-tetra-p-tolyporphyrin (TTP) are described. All target compounds are characterized with UV-Vis spectroscopy and MALDI-TOF mass spectrometry. The freebase porphyrins and non-paramagnetic metalloporphyrins are further characterized by proton nuclear magnetic resonance spectroscopy and all proton resonances are assigned. Electrochemical measurements show the reduction potential of the fluorinated phenyl substituted porphyrins is shifted to less negative values as compared to the reduction potential measured using non-fluorinated analogs. These results illustrate the ability to use fluorine as a synthetic tool for altering the electronic properties of metalloporphyrins. Further, these findings serve a critical role in choosing metalloporphyrin electrocatalysts with the appropriate energetic and optical properties for integration to semiconductors with applications to solar-to- fuels technologies.
ContributorsNanyangwe, Sylvia Kapya (Author) / Moore, Gary (Thesis director) / Van Horn, Wade (Committee member) / School of Criminology and Criminal Justice (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Recent evidence suggests that youth from affluent and upper-middle-class, white collar families are at high risk for maladaptive behaviors, such as aggression, rule breaking, and substance use. A major hypothesized underlying factor is lax parental discipline that involves low repercussions for errant behaviors such as substance use—also known as perceived parents’ “containment” of such behaviors. In this study, the focus is on multiple dimensions of perceived containment among parents and school authorities, in relation to both externalizing problems and drug use behaviors. These associations are examined in four different schools: two boarding schools and two day schools. Results show much stronger links with maladjustment for perceived containment by parents as opposed to perceived containment by school. The largest significant effects within the containment indices were found to be between parent containment of drug use and the levels of substance use behaviors reported by students. These effects were found across gender and all schools, indicating robust links. Overall, the most robust index studied was the perceived parental monitoring variables; monitoring effects were stronger than effects from any containment variables. Students who perceived the highest levels of parental monitoring exhibited the least amount of externalizing behaviors across all schools and genders. A possible explanation includes students perceiving that their parents monitor their behavior due to caring on the behalf of the parent, which then leads to fewer externalizing outcomes. These results suggest that the most effective means of decreasing substance use levels seem to lie within the parents of the students and not the schools.
ContributorsHudson, Johnny (Author) / Luthar, Suniya (Thesis director) / Glenberg, Arthur (Committee member) / Cavanaugh Toft, Carolyn (Committee member) / School of Molecular Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
Cancer is a disease that occurs in many and perhaps all multicellular organisms. Current research is looking at how different life history characteristics among species could influence cancer rates. Because somatic maintenance is an important component of a species' life history, we hypothesize the same ecological forces shaping the life history of a species should also determine its cancer susceptibility. By looking at varying life histories, potential evolutionary trends could be used to explain differing cancer rates. Life history theory could be an important framework for understanding cancer vulnerabilities with different trade-offs between life history traits and cancer defenses. Birds have diverse life history strategies that could explain differences in cancer suppression. Peto's paradox is the observation that cancer rates do not typically increase with body size and longevity despite an increased number of cell divisions over the animal's lifetime that ought to be carcinogenic. Here we show how Peto’s paradox is negatively correlated for cancer within the clade, Aves. That is, larger, long-lived birds get more cancer than smaller, short-lived birds (p=0.0001; r2= 0.024). Sexual dimorphism in both plumage color and size differ among Aves species. We hypothesized that this could lead to a difference in cancer rates due to the amount of time and energy sexual dimorphism takes away from somatic maintenance. We tested for an association between a variety of life history traits and cancer, including reproductive potential, growth rate, incubation, mating systems, and sexual dimorphism in both color and size. We found male birds get less cancer than female birds (9.8% vs. 11.1%, p=0.0058).
ContributorsDolan, Jordyn Nicole (Author) / Maley, Carlo (Thesis director) / Harris, Valerie (Committee member) / Boddy, Amy (Committee member) / School of Molecular Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The primary objective of this project is to further the knowledge about SCL26 family of anion transporters. The goals of the experiment were to find the lowest sulfate concentration where the yeast without Sulp1 and Sulp2 is able to grow, but it grows very slowly, and to find a higher sulfate concentration where the yeast grows quickly, with or without the sulfate transporters. The lowest sulfate concentration where the yeast without the sulfate transporters is able to grow was determined to be 2-4 mM, however, this range can likely be refined by more quantitative analytical methods. At a sulfate concentration of 20 mM sulfate or higher, the yeast is able to grow quickly without high-affinity sulfate transporters. The next step in the project is to re-introduce the Sulp1 and Sulp2 genes into the yeast, so that growth in low and high sulfate conditions can be compared with and without the Sulp1 and Sulp2 proteins. The long-term goals of the project are to bring experience with yeast to Dr. Nannenga’s structural discovery lab, to determine if yeast sulfate transporters respond in the same way to drug candidates as human sulfate transporters, and to determine the structure of the proteins using cryo-electron microscopy.
ContributorsCall, Nicolas I (Author) / Nannenga, Brent (Thesis director) / Wang, Xuan (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The aims of this project are: (i) to identify structural and molecular changes in the brains of 3xTg-AD mice and (ii) to determine whether decreasing S6K1 protects the brain from these changes. To achieve our goals, we decided to remove one copy of the S6K1 gene in 3xTg-AD mice by breeding them with S6K1 knockout mice (S6K1+/-). In previous studies, we have seen that reducing S6K1 levels in 3xTg-AD mice improved spatial memory and synaptic plasticity which was associated with reduced A and tau pathology. Here, we used a multiparametric MRI to assess volumetric and blood flow changes in the brain of 20-month-old 3xTg-AD mice. We found that 3xTg-AD/S6K1+/- mice had higher blood flow and cortical volume compared to 3xTg-AD mice. However, we saw no significant differences between 3xTg-AD mice and NonTg mice. We further found A levels and plaque numbers were significantly lower in 3xTg-AD/S6K1+/- mice compared to 3xTg-AD mice. This reduction in plaques could account for the improvement in blood flow in 3xTg-AD/S6K1+/- mice. To try to understand the reason behind the increase in cortical volume in the 3xTg-AD/S6K1+/- when compared to the 3xTg-AD, we measured markers of synaptic density, PSD95, and synaptophysin. We found that PSD95 levels were not different between the four groups. However, synaptophysin levels were significantly lower in 3xTg-AD mice compared to NonTg levels and returned to baseline levels in 3xTg-AD mice lacking one copy of the S6K1 gene. This difference in synaptophysin could explain, at least in part, the difference in volume between the four groups analyzed. Overall, this represents the first evidence showing that reducing mTOR signaling improves blood flow and cortical volume in a mouse model of AD.
ContributorsShukla, Prakriti (Author) / Oddo, Salvatore (Thesis director) / Caccamo, Antonella (Committee member) / Jankowsky, Joanna (Committee member) / School of Molecular Sciences (Contributor) / School of Public Affairs (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Currently, many patients suffer from post-circumcision complications caused by poor patient selection and/or poor technique of the practicing physician. In addition, the majority of medical practitioners are incapable of/unwilling to conduct specific circumcision procedures on their patients. In the end, this either results in unsatisfied patient families, who unwillingly have their children circumcised using methods contrary to their belief, or results in individuals who are not certified practitioners of medicine conducting the procedures, greatly increasing the risk of the patients experiencing preventable complications. In order to locally address the aforementioned problems, this thesis committee, consisting of Dr. Frank Infurna, Dr. Justin Ryan, and Dr. Zachary Zuniga, and I, developed a training module that standardized the instruction that interns, residents, attendings, fellows, hospitalists, and other interested physicians will receive regarding neonatal circumcision at Phoenix Children's Hospital. To begin, the pre-operative, intra-operative, and post-operative procedures related to the Gomco clamp neonatal circumcision procedure were heavily researched using literature sourced from library databases and consultation of specialists, such as Dr. Zuniga. Given that the training was developed to instruct individuals within the medical field, the material was then truncated to promote succinctness and specificity towards the targeted population. In order to convey the specific techniques that are clinically preferred to be used in the procedure, one of Dr. Zuniga's Gomco clamp neonatal circumcision procedures was recorded and converted into GIFs, with each GIF depicting a specific technique of the procedure. The aforementioned materials were then arranged into a slide deck in order to mitigate the need for future training facilitators to tamper with the material in the process of creating visuals to be used during the training. Given the sensitivity of the material included in the slide deck, it will only be available for use on Phoenix Children's Hospital premises. To incorporate instruction regarding both the traditional (Gomco clamp) and religiously-preferred circumcision techniques into the training module, appointments, consisting of discussions regarding the procedural, cultural, and social facets that must be taken into consideration when conducting a circumcision procedure on a patient from a Muslim family, were set-up with pediatric physicians, currently practicing in Abu Dhabi, United Arab Emirates, who have specialized knowledge of conducting circumcisions in the Middle East. Since Brit Milah, the Jewish circumcision ceremony, is, unlike in Islam, required to be conducted by a Mohel in either a synagogue or house, it was not covered as holistically as "Khtan", Islamic circumcision, which is less heavily regulated. Thus far, the training module has been piloted twice, once with a group of medical students and physicians and once with medical education program directors and instructors. The critique from both sessions has been used to prepare the material for use in neonatal circumcision training sessions that will be introduced in clerkship and residency curriculum. In the future, the results of this implementation can be used to prepare the module for submission to the American Academy of Pediatrics to be made a prerequisite for physicians to undergo before conducting neonatal circumcisions.
ContributorsMeraban, Amir Reza (Author) / Infurna, Frank (Thesis director) / Ryan, Justin (Committee member) / Zuniga, Zachary (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
I investigated if race/ethnicity was associated with self- and peer-reported victimization and aggression in a sample of 5th through 8th graders (N = 383, 51% males) from two schools in which Hispanic/Latino students were the ethnic-racial majority. Self-reported victimization did not differ between races. In contrast, White students often had higher peer-reported victimization relative to Hispanic and Multi-racial students. Few significant associations were found for aggression. There was some, albeit inconsistent, support for the idea that power imbalance based on race/ethnicity is shifted by numbers. In the future, researchers should conduct studies aimed verifying this notion and that are tailored toward answering questions of mechanism.
ContributorsMitiku, Helen (Author) / Wilkens, Natalie (Thesis director) / Lindstrom Johnson, Sarah (Committee member) / White, Rebecca (Committee member) / School of Molecular Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05