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- Creators: School of Life Sciences
Description
Experimentation with glaze materials resulted in 2 functional and interesting base glazes with multiple color variants each. A semi-matte stoneware glaze was created, however after being unable to replicate a specific coloring without drying out the glaze, it was discovered that using this glaze to spray over specific studio glazes produced a more pleasant color effect than the glaze by itself. A glossy clear glaze was created. The glaze crazed minimally, and color variants were created with the rare earth metals erbium, praseodymium, and neodymium, resulting in celadon-like glazes that were pink, green, and bluish purple respectively. Finally, A semi-matte stoneware glaze with high spodumene content was created with two specific color variations
ContributorsVilen, Zachary Kwochka (Author) / Beiner, Susan (Thesis director) / Steimle, Timothy (Committee member) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
In vitro gametogenesis (IVG) research has been growing in countries like Japan, US, and China after the development of stem cell research and other scientific advancements as well as because of the perception of infertility as a domestic and international problem. IVG research’s progress has been deliberated internationally, with discussion of questions, challenges, and possibilities that have arisen and may arise in the future as the technology is adopted by different countries. The first section introduces the meaning of IVG, explains the importance of review by scientists and citizens for IVG, and describes a rise in infertility reported in multiple developed countries that could be addressed by IVG. The second section discusses IVG’s applications and implications using 5 ethical categories articulated by Obama’s Presidential Commission for the Study of Bioethical Issues: Public Beneficence, Responsible Stewardship, Intellectual Freedom and Responsibility, Democratic Deliberation, and Justice and Fairness. These five ethical principles were intended for analysis of emerging technologies, and IVG is an emerging technology with possible integration into clinical settings. Among the principles, it seemed that a major weak point of inquiry concerns LGBT+ and disability inclusion, especially of gender dysphoric and transgender people who may experience higher rates of infertility and have a harder time conceiving due to a mix of discrimination, gender dysphoria, and infertility due to hormone replacement therapy (HRT) treatment or gender/sex reassignment surgeries (GRSs/SRSs) that may impair or remove reproductive body parts. A number of other ethical considerations arise about this technology.
ContributorsVillarreal, Lance Edward (Author) / Maienschein, Jane (Thesis director) / Ellison, Karin (Committee member) / Wilson-Rawls, Jeanne (Committee member) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Fusion protein immunotherapies such as the bispecific T cell engager (BiTE) have displayed promising potential as cancer treatments capable of engaging the immune system against tumor cells. It has been shown that chlorotoxin, a 36-amino peptide found in the venom of the deathstalker scorpion (Leiurus quinquestriatus), binds specifically to glioblastoma (GBM) cells without binding healthy tissue, making it an ideal GBM cell binding moiety for a BiTE-like molecule. However, chlorotoxin’s four disulfide bonds pose a folding challenge outside of its natural context and impede production of the recombinant protein in various expression systems, including those relying on bacteria and plants. To overcome this difficulty, we have engineered a truncated chlorotoxin variant (Cltx∆15) that contains just two of the original eight cystine residues, thereby capable of forming only a single disulfide bond while maintaining its ability to bind GBM cells. We further created a BiTE (ACDClx∆15) which tethers Cltx∆15 to a single chain ⍺-CD3 antibody in order to bring T cells into contact with GBM cells. The gene for ACDClx∆15 was cloned into a pET-11a vector for expression in Escherichia coli and isolated from inclusion bodies before purification via affinity chromatography. Immunoblot analyses confirmed that ACDClx∆15 can be expressed in E. coli and purified with high yield and purity; moreover, flow cytometry indicated that ACDClx∆15 is capable of binding GBM cells. These data warrant further investigation into the ability of ACDClx∆15 to activate T cells against GBM cells.
ContributorsSchaefer, Braeden Scott (Author) / Mor, Tsafrir (Thesis director) / Mason, Hugh (Committee member) / Cook, Rebecca (Committee member) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Infectious disease in wild animals has historically been a challenge that is difficult to overcome, primarily because isolating a disease outbreak to prevent further transmission in these types of populations is nearly impossible. Wild animals are free to roam, and humans often have limited means of tracking infection in populations. Vaccines and treatments can be formulated but are often somewhat impractical for wild populations because it is not feasible to vaccinate or treat every member in a susceptible community. One such pathogen, Batrochochytrium dendrobatidis (Bd) is infecting amphibian populations around the world to the point where many species are already extinct. Even though finding an effective preventative for the fungal pathogen may not mean that I am able to reach every member in a population, it may mean the difference between extinction and eventual release back into the wild for threatened populations.
In this study I hoped to create an attenuated version of Batrochochytrium dendrobatidis, by using a novel laser technology: SEPHODIS. This laser technology disrupts hydrogen bonds between proteins in the lumen of the cell while simultaneously preserving the membrane and associated proteins on the outside of the cell. This process ultimately affects the pathogenicity of the target but leaves identity markers intact so that the host immune system may recognize the pathogen and create antibodies against it. The laser was ultimately effective at killing Bd fungal cells, and I did observe a significant change in the appearance of the cells. However, samples obtained after exposure to the laser were contaminated and more research is needed to determine if SEPHODIS could be a feasible method for vaccine production.
In this study I hoped to create an attenuated version of Batrochochytrium dendrobatidis, by using a novel laser technology: SEPHODIS. This laser technology disrupts hydrogen bonds between proteins in the lumen of the cell while simultaneously preserving the membrane and associated proteins on the outside of the cell. This process ultimately affects the pathogenicity of the target but leaves identity markers intact so that the host immune system may recognize the pathogen and create antibodies against it. The laser was ultimately effective at killing Bd fungal cells, and I did observe a significant change in the appearance of the cells. However, samples obtained after exposure to the laser were contaminated and more research is needed to determine if SEPHODIS could be a feasible method for vaccine production.
ContributorsRidley, Kylie Madison (Author) / Collins, James (Thesis director) / Tsen, Kong-Thon (Committee member) / Brus, Evan (Committee member) / School of Art (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Colorectal cancer is the third most common type of cancer that affects both men and women and the second leading cause of death in cancer related deaths[1, 2]. The most common form of treatment is chemotherapy followed by radiation, which is insufficient to cure stage four cancers[3]. Salmonella enteric has long been shown to have inherent tumor targeting properties and have been able to penetrate and exist in all aspects of the tumor environment, something that chemotherapy is unable to achieve. This lab has developed a genetically modified Salmonella typhimurium (GMS) which is able to deliver DNA vaccines or synthesized proteins directly to tumor sites. These GMS strains have been used to deliver human TNF-related apoptosis inducing ligand (TRAIL) protein directly to tumor sites, but expression level was limited. It is the hope of the experiment that codon optimization of TRAIL to S. typhimurium preferred codons will lead to increased TRAIL expression in the GMS. For preliminary studies, BALB/c mice were subcutaneously challenged with CT-26 murine colorectal cancer cells and treated with an intra-tumor injection with either PBS, strain GMS + PCMV FasL (P2), or strain GMS + Pmus FasL). APC/CDX2 mutant mice were also induced to develop human colon polyps and treated with either PBS, strain GMS + vector (P1), P2, or P3. The BALB/c mouse showed statistically significant levels of decreased tumor size in groups treated with P2 or P3. The APC/CDX2 mouse study showed statistically significant levels of decreased colon polyp numbers in groups treated with P3, as expected, but was not significantly significant for groups treated with P1 and P2. In addition, TRAIL was codon optimized for robust synthesis in Salmonella. The construct will be characterized and evaluated in vitro and in vivo. Hopefully, the therapeutic effect of codon optimized TRAIL will be maximal while almost completely minimizing any unintended side effects.
ContributorsCrawford, Courtney Rose (Co-author) / Crawford, Courtney (Co-author) / Kong, Wei (Thesis director) / Shi, Yixin (Committee member) / Fu, Lingchen (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Amphibians around the world are suffering the effects of the chytrid fungus, Batrachochytrium dendrobatidis (Bd). Whenever amphibians are housed in captivity, they must go through a decontamination protocol to ensure they are not infected with diseases such as Bd. Itraconazole is the most commonly used fungicide used in these protocols. This study set out to determine if Bd could develop resistance or tolerance to itraconazole. Two 24 well plates were prepared with different concentrations of itraconazole with Bd zoospores added. Plate 1 had concentrations similar to what animals are currently being treated with in decontamination protocols. Plate 2 had concentrations at and below the published minimum inhibitory concentration values (MIC). Plate 1 displayed the ability of itraconazole to kill Bd sporangia with higher concentrations and Plate 2 showed that even under published MIC values, Bd still struggled to complete its reproductive cycle. I find the evolution of a resistant/tolerant strain of Bd unlikely given the efficacy of this drug, the sensitivity of Bd to itraconazole, and the lack of evidence of the completion of Bd’s reproductive cycle under the conditions used in this study.
ContributorsSommer, Bradley Dean (Author) / Collins, James (Thesis director) / Roberson, Robert (Committee member) / Brus, Evan (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Anthropogenic land-use change, and its resulting habitat fragmentation, have restricted and isolated jaguar (Panthera onca) populations across their historic range of South, Central, and North America. As a result, jaguar are now globally listed as Near Threatened by the IUCN Red List of threatened species (Quigley et al., 2017). Southwestern Costa Rica maintains two distinct jaguar populations: a small relictual “sink” population in Corcovado National Park on the Osa Peninsula and a larger but marginalized “source” population in the La Amistad International Park in the Talamanca mountains to the Northeast. The small and highly restricted population located between Corcovado (425 km²) and Piedras Blancas (140 km²) National Parks has been isolated for more than 50 years, while La Amistad International Park (2306 km²) in the north contains a significantly larger population, but in suboptimal montane habitat. A mosaic of pastures, coffee plantations, African oil palm groves, pineapple plantations, and human communities separate these two populations. My paper offers an analysis of the habitat suitability between the montane forest of the Talamanca Mountains and the coastal forest of the Osa Peninsula for jaguars within a proposed conservation corridor. While forest was determined to be the most optimal habitat type for jaguar, mangroves and small scale coffee were also found to be suitable in the context of a corridor. Palm was identified as having marginal suitability, while pasture and pineapple appeared poorly suited for jaguar, particularly due to the lack of prey species and vegetation cover. Urban areas were found to be entirely unsuitable. While human activities have highly fragmented the study area, my analysis suggests that human-dominated landscapes, such as agriculture, can still maintain connectivity, especially when paired with actions to improve conservation, education, and sustainable practices. My research will further support the establishment of a proposed wildlife corridor, which could greatly improve connectivity for wildlife across the region and facilitate movement of jaguar and prey species between the isolated Talamancan and Osa populations.
ContributorsJohnson, Annie Laura (Author) / Lewis, Jesse (Thesis director) / Schipper, Gerrit (Committee member) / School of Politics and Global Studies (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The prevalence of excessive weight gain (obesity) has steadily increased since about 1980. Excessive weight gain is associated with many comorbidities; thus, a successful treatment is needed. The most common form of non-surgical treatment for excessive weight gain is caloric restriction with the intent to reduce body weight by 10%. Though this treatment is successful at reducing body weight, it often fails at maintaining the weight loss. Dietary menthol has been suggested as a possible treatment for excessive weight gain and has produced promising results as a preventative method for excessive weight gain. Our studies aimed at reducing weight regain and maintaining caloric restriction by feeding male Sprague-Dawley rats 0.5% dietary menthol during a period of caloric restriction, aimed at reducing their body weight by 10%, following an experimental period where the rats were fed a high-fat diet (HFD) or low-fat diet (LFD). The effects of the dietary menthol were observed during the weight regain period following the caloric restriction period. Two studies were conducted, and both were unable to achieve a maintenance of weight loss following caloric restriction, although our first study was able to produce a delay in weight regain and did not show any evidence of increased thermogenesis in menthol-treated rats. Our findings differ from the findings of previous studies on dietary menthol which could possibly be due to species effects, differences in procedures, age effects, or effects of different fatty acid compositions. The contrasting results in our studies could be due to genetic differences between litters used or a difference in manufacturing of the menthol diet between studies. Given the partial response to menthol in the first study, it can be suggested that the concentration of 0.5% may be below the threshold of menthol sensitivity for some rats. Future research should focus on increasing the concentration of dietary menthol from 0.5% to 1%, since the current concentration did not yield a reduction in weight regain or maintenance of caloric restriction.
ContributorsRascon, Kasandra (Author) / Herman, Richard (Thesis director) / Sweazea, Karen (Committee member) / Kim, Minjoo (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
According to Jean Piaget, a prominent cognitive development psychologist in 1954, infants should have an understanding of object permanence at 12 months of age. Current research has backed this idea and shown that children younger than 2 years of age understand object permanence- shown through their increased looking times to inconsistent displays in which a moving object appears to have fallen through a solid shelf. However, current research used active search tasks with 2 year olds and found that they failed to search for the object consistently. My thesis explores why 2 year olds are failing search tasks if infants are appearing the understand object permanence with their looking responses. The Theory of Mind Lab at ASU designed a simple two door/two room apparatus to test 2 year olds’ ability to search for an object once it goes out of sight. Two doors open to two rooms separated by a green wall that extends above the front wall. Results showed that 2-year-olds randomly searched for the object. Perhaps children were not able to clearly differentiate the two separate spaces and ultimately started guessing because they assumed both doors go to the same room. Therefore, my thesis involved adding a ‘hallway’ between the two rooms to help children mentally separate the two spaces by showing them the bottom of the barrier. Despite the hallway, results showed that 2-year-olds again hardly performed above chance across all 6 trials. To remove the social aspects and the need to coordinate motor movement with knowledge of the object’s location, I designed a Visual Anticipation Task with automatic doors that required 2-year olds to merely look at the correct door for the hidden object. Results showed that children looked correctly at the first location correctly but when hidden in a new location in the second trial, perseverated and looked back at the first location. These results showed that 2-year olds do not understand object permanence at this age when it comes to both searching and looking.
ContributorsVirani, Sanya Z (Co-author) / Virani, Sanya (Co-author) / Fabricius, William (Thesis director) / Kupfer, Anne (Committee member) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Human activity produces ambient noise that potentially alters species’ abilities to communicate with each other—among other impacts. Given that birds are known to be sensitive to structural changes in habitat and highly communicative through sound, it is beneficial to understand how changing acoustic ecologies and ambient noise impact birds’ ability to communicate in their respective environments. In this study, mockingbird calls from an urban, desert, and intermediate study site were recorded and analyzed for differences in acoustic properties. Acoustic properties such as frequency and amplitude differed significantly across sites as it was determined that mockingbirds in urban areas increase both the peak frequency and amplitude of their calls in order to communicate. This study identifies what these changes in acoustic properties mean in relation to the survival and conservation of birds and concludes with recommendations for novel research.
ContributorsReynolds, Bailey Susana (Author) / Pearson, David (Thesis director) / Walters, Molina (Committee member) / School of Sustainability (Contributor) / School of Life Sciences (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05