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- Creators: School of Life Sciences
- Creators: Prokofiev, Sergey, 1891-1953
Description
Species survive by adapting to what is demanded by their environment. In constant and fluctuating environments, specialist and generalists should be favored, respectively. However, the costs and benefits of adaptation can depend on a variety of factors that alter the intensity of the specialist-generalist trade-off. We examined flight performance to determine how well flies that evolved in constant and fluctuating temperatures acclimated to hot and cold temperatures. We predicted that flies would perform best at temperatures most similar to the ones the flies evolved at. Best performance was found when rearing and testing temperatures aligned with the temperature at which a genotype had evolved, with the generalist sharing the best and worst performance combination with the constant thermally evolved flies. Interestingly, evolved and reared temperatures had equal impact on flight performance. It was also observed that rearing at 25°C resulted in flies with the best fitness. These results contribute to the specialist-generalist theory and the idea that long term cold development is restricting in terms of range for thermal performance.
ContributorsLe Vinh Thuy, Jacqueline (Author) / Angilletta, Michael (Thesis director) / VandenBrooks, John (Committee member) / Czarnoleski, Marcin (Committee member) / School of Molecular Sciences (Contributor) / Economics Program in CLAS (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Nitrous oxide (N2O) is a major contributor to the greenhouse effect and to stratospheric ozone depletion. In soils, nitrogen reduction is performed by biotic and abiotic processes, including microbial denitrification and chemical denitrification. Chemical denitrification, or chemodenitrification, is the abiotic step-wise reduction of nitrate (NO3-), nitrite (NO2-), or nitric oxide (NO) to N2O in anoxic environments, with high turnover rates particularly in acidic soils. Chemodenitrification was identified in various environments, but the mechanism is still not understood. In this study, the factors influencing abiotic reduction of NO2- to N2O in acidic tropical peat soil are examined. These factors include pH, organic matter content, and dissolved ferrous iron. Anoxic peat soil from sites located in the Peruvian Amazon was used for incubations. The results show that peat soil (pH ~4.5) appears to reduce NO2- more quickly in the presence of lower pH and higher Fe(II) concentrations. NO2- is completely reduced in excess Fe(II), and Fe(II) is completely oxidized in excess NO2-, providing evidence for the proposed mechanism of chemodenitrification. In addition, first order reaction rate constants kFe(II) and kNO2- were calculated using concentration measurements over 4 hours, to test for the hypothesized reaction rate relationships kFe(II): kFe(II) kFe(II)~NO2- > kFe(II)>NO2- and kNO2-: kFe(II)NO2-. The NO2- k values followed the anticipated pattern, although the Fe(II) k value data was inconclusive. Organic material may also play a role in NO2- reduction through chemodenitrification, and future experimentation will test this possibility. How and to what extent the pH and the concentrations of organic matter and Fe(II) affect the kinetic rate of chemodenitrification will lend insight into the N2O production potential of natural tropical peatlands.
ContributorsTylor, Kaitlyn Marie (Author) / Cadillo-Quiroz, Hinsby (Thesis director) / Day, Thomas (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The Paradise Valley Family Resource Center (PVFRC) is a not for profit, community based organization funded by First Things First and a part of the Paradise Valley Unified School District (PVUSD) in Phoenix, Arizona. The mission of this organization is to connect and strengthen families with children from birth to five years old in the Phoenix valley. The PVFRC longed to be more cognizant of what the needs of the community they serve are, and how they, as an organization, can administer programs of value to the community. Hence, the PVFRC entered a partnership with the Community Action Research Experiences (CARE) program at Arizona State University to develop a research proposal to improve their effectiveness and efficiency at achieving their mission. The purpose of this research project was to identify and evaluate the needs of the families with children ages birth to five within the community, to improve upon existing programs and services or to implement new programs, and to discover more effective modes of awareness and advertisement to the community about the programs and services the PVFRC provides. The main research questions of the experiment included asking participants about what programs and services they need, wish, or want to exist at the PVFRC, what barriers or gaps they see or experience regarding attending the PVFRC, how did participants learn about the PVFRC, and what are the best ways to contact families in their community. The methods of the research included conducting focus group interviews with families who utilize the programs and services at the PVFRC and with early childhood professionals in the Paradise Valley Unified School District (PVUSD), which included social workers and preschool teachers. A total of 25 participants were interviewed (10 families, 6 social workers, and 9 preschool teachers) and responses from the interviews were coded by the researcher. The results of the research was that the PVFRC is meeting many needs and current families are satisfied, participants desire some changes to current programs and services, and the best modes of advertisement and awareness were "word of mouth" and the internet. It was recommended that in order to better achieve their mission, it is advised that the PVFRC make appropriate changes to programs and services as suggested by the participants, connect with mom's or parents groups in the community, collaborate with preschool teachers on the front line, and increase their online presence through the use of social media and their website.
ContributorsHoran, Mary Jensen (Author) / Foster, Stacie (Thesis director) / Brougham, Jennifer (Committee member) / Dumka, Larry (Committee member) / T. Denny Sanford School of Social and Family Dynamics (Contributor) / School of Molecular Sciences (Contributor) / School for the Science of Health Care Delivery (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Triops (Branchiopoda: Notostraca) and Streptocephalus (Branchiopoda: Anostraca) are two crustaceans which cohabitate in ephemeral freshwater pools. They both lay desiccation resistant eggs that disperse passively to new hydrologically isolated environments. The extent of genetic distance among regions and populations is of perennial interest in animals that live in such isolated habitats. Populations in six natural ephemeral pool habitats located in two different regions of the Sonoran Desert and a transition area between the Sonoran and Chihuahuan Deserts were sampled. Sequences from Genbank were used for reference points in the determination of species as well as to further identify regional genetic distance within species. This study estimated the amount of within and between genetic distance of individuals from each region and population through the use of a neutral marker, cytochrome oxidase I (COI). We concluded that, although the method of passive dispersal may differ between the two genera, the differences do not results in different patterns of genetic distances between regions and populations. Furthermore, we only found the putative species, Triops longicaudatus "short", with enough distinct speciation. Although Triops longicaudatus "long" and Triops newberryi may be in the early stages of speciation, this study does not find enough support to conclude that they have separated.
ContributorsMurphy Jr., Patrick Joseph (Author) / Rutowski, Ronald (Thesis director) / Cartwright, Reed (Committee member) / Lessios, Nikos (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Dogs' health and wellbeing is of great importance to their owners. The most common nutritional problem for pet dogs is obesity, with 22-40% of pet dogs being classified as overweight or obese. With many adverse health effects associated with obesity, this is a major concern for owners and veterinarians. The degree to which dogs enjoy consuming certain foods can have substantial implications for their body weight, so it is important to understand which aspects of foods make them appealing to dogs. This study aimed to determine whether nutritional aspects of commercial dog foods predict dogs' preferences for those foods. It was found that consumption preference is positively correlated with protein content (p < .001), therefore implying that the protein content of commercial dry dog foods may predict dogs' consumption preferences. Consumption preferences were not predicted by other available measures of food content or caloric value. Dogs' preference for foods high in protein content may be due to the satiating effect of protein. Since foods high in protein both reduce the amount of energy consumed and are found to be palatable to dogs, high-protein dog foods may offer a way for dog food manufacturers, veterinarians, and pet owners to combat obesity in pet dogs.
ContributorsPrevost, Emily Danielle (Author) / Wynne, Clive (Thesis director) / Hall, Nathaniel (Committee member) / School of Life Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Breast cancer is the leading cause of cancer-related deaths of women in the united states. Traditionally, Breast cancer is predominantly treated by a combination of surgery, chemotherapy, and radiation therapy. However, due to the significant negative side effects associated with these traditional treatments, there has been substantial efforts to develop alternative therapies to treat cancer. One such alternative therapy is a peptide-based therapeutic cancer vaccine. Therapeutic cancer vaccines enhance an individual's immune response to a specific tumor. They are capable of doing this through artificial activation of tumor specific CTLs (Cytotoxic T Lymphocytes). However, in order to artificially activate tumor specific CTLs, a patient must be treated with immunogenic epitopes derived from their specific cancer type. We have identified that the tumor associated antigen, TPD52, is an ideal target for a therapeutic cancer vaccine. This designation was due to the overexpression of TPD52 in a variety of different cancer types. In order to start the development of a therapeutic cancer vaccine for TPD52-related cancers, we have devised a two-step strategy. First, we plan to create a list of potential TPD52 epitopes by using epitope binding and processing prediction tools. Second, we plan to attempt to experimentally identify MHC class I TPD52 epitopes in vitro. We identified 942 potential 9 and 10 amino acid epitopes for the HLAs A1, A2, A3, A11, A24, B07, B27, B35, B44. These epitopes were predicted by using a combination of 3 binding prediction tools and 2 processing prediction tools. From these 942 potential epitopes, we selected the top 50 epitopes ranked by a combination of binding and processing scores. Due to the promiscuity of some predicted epitopes for multiple HLAs, we ordered 38 synthetic epitopes from the list of the top 50 epitope. We also performed a frequency analysis of the TPD52 protein sequence and identified 3 high volume regions of high epitope production. After the epitope predictions were completed, we proceeded to attempt to experimentally detected presented TPD52 epitopes. First, we successful transduced parental K562 cells with TPD52. After transduction, we started the optimization process for the immunoprecipitation protocol. The optimization of the immunoprecipitation protocol proved to be more difficult than originally believed and was the main reason that we were unable to progress past the transduction of the parental cells. However, we believe that we have identified the issues and will be able to complete the experiment in the coming months.
ContributorsWilson, Eric Andrew (Author) / Anderson, Karen (Thesis director) / Borges, Chad (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Learning how to manage time efficiently is something that many people struggle with, college students in particular. The purpose of this study was to examine if personalization via self-experimentation of strategies to improve time management skills is a useful strategy for achieving this goal. This study used a multiple baseline approach with three phases: phase one, the baseline, phase two, which included individuals receiving examples of plausible strategies to improve time management skills, and phase three, which involved the self-experimentation component. Results of this study suggest no significant changes in time management based on self-reported completion of tasks but do indicate a trend towards improved time management skills overall based on the time management questionnaire taken at the beginning and end of the study. These results suggest that further exploration in the use of self-experimentation strategies for improving time management is likely warranted but that current strategies likely require additional research. Results from the interviews indicate that the self-experimentation strategy, as delivered via PACO does increase awareness and thinking about time management.
ContributorsCope, Breanna (Author) / Hekler, Eric (Thesis director) / Buman, Matthew (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Transient Receptor Potential (TRP) ion channels are a diverse family of nonselective, polymodal sensors in uni- and multicellular eukaryotes that are implicated in an assortment of biological contexts and human disease. The cold-activated TRP Melastatin-8 (TRPM8) channel, also recognized as the human body's primary cold sensor, is among the few TRP channels responsible for thermosensing. Despite sustained interest in the channel, the mechanisms underlying TRPM8 activation, modulation, and gating have proved challenging to study and remain poorly understood. In this thesis, I offer data collected on various expression, extraction, and purification conditions tested in E. Coli expression systems with the aim to optimize the generation of a structurally stable and functional human TRPM8 pore domain (S5 and S6) construct for application in structural biology studies. These studies, including the biophysical technique nuclear magnetic spectroscopy (NMR), among others, will be essential for elucidating the role of the TRPM8 pore domain in in regulating ligand binding, channel gating, ion selectively, and thermal sensitivity. Moreover, in the second half of this thesis, I discuss the ligation-independent megaprimer PCR of whole-plasmids (MEGAWHOP PCR) cloning technique, and how it was used to generate chimeras between TRPM8 and its nearest analog TRPM2. I review steps taken to optimize the efficiency of MEGAWHOP PCR and the implications and unique applications of this novel methodology for advancing recombinant DNA technology. I lastly present preliminary electrophysiological data on the chimeras, employed to isolate and study the functional contributions of each individual transmembrane helix (S1-S6) to TRPM8 menthol activation. These studies show the utility of the TRPM8\u2014TRPM2 chimeras for dissecting function of TRP channels. The average current traces analyzed thus far indicate that the S2 and S3 helices appear to play an important role in TRPM8 menthol modulation because the TRPM8[M2S2] and TRPM8[M2S3] chimeras significantly reduce channel conductance in the presence of menthol. The TRPM8[M2S4] chimera, oppositely, increases channel conductance, implying that the S4 helix in native TRPM8 may suppress menthol modulation. Overall, these findings show that there is promise in the techniques chosen to identify specific regions of TRPM8 crucial to menthol activation, though the methods chosen to study the TRPM8 pore independent from the whole channel may need to be reevaluated. Further experiments will be necessary to refine TRPM8 pore solubilization and purification before structural studies can proceed, and the electrophysiology traces observed for the chimeras will need to be further verified and evaluated for consistency and physiological significance.
ContributorsWaris, Maryam Siddika (Author) / Van Horn, Wade (Thesis director) / Redding, Kevin (Committee member) / School of Molecular Sciences (Contributor) / Department of English (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Space microbiology, or the study of microorganisms in space, has significant applications for both human spaceflight and Earth-based medicine. This thesis traces the evolution of the field of space microbiology since its creation in 1935. Beginning with simple studies to determine if terrestrial life could survive spaceflight, the field of space microbiology has grown to encompass a substantial body of work that is now recognized as an essential component of NASA' research endeavors. Part one provides an overview of the early period of space microbiology, from high-altitude balloon and rocket studies to work conducted during the Apollo program. Part two summarizes the current state of the field, with a specific focus on the revolutionary contributions made by the Nickerson lab at the Biodesign Institute at ASU using the NASA-designed Rotating Wall Vessel (RWV) Bioreactor. Finally, part three highlights the research I've conducted in the Nickerson lab, as well as continuing studies within the field of space microbiology.
ContributorsMcCarthy, Breanne E. (Author) / Lynch, John (Thesis director) / Foy, Joseph (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Musical interpretation is challenging when one's goal is to evoke an emotional response from an audience. In order to develop a well-informed interpretation of Mozart's Fantasia in D minor K. 397, a study was conducted on the historical background of the piece and various performances by well-regarded performers. Fantasias are written works, but improvisatory by nature. Mozart's fantasias were influenced by C. P. E. Bach's, which included sudden changes in emotion. An Emil Gilels performance provided a classically trained approach, while Mitsuko Uchida's performance provided an emotional approach. Colin Tilney and John Irving performances elucidated the sound of the instruments that Mozart would have been composing with. Altogether, the research culminated in an interpretation of the D minor Fantasia that endeavored to capture the essence of fantasy, improvisation and emotion.
ContributorsMo, Gina Nan (Author) / Emmery, Laura (Thesis director) / Creviston, Hannah (Committee member) / Department of Psychology (Contributor) / School of International Letters and Cultures (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05