Matching Items (4)
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- All Subjects: Biochemistry
- Language: English
Description
The elaborate signals of animals are often costly to produce and maintain, thus communicating reliable information about the quality of an individual to potential mates or competitors. The properties of the sensory systems that receive signals can drive the evolution of these signals and shape their form and function. However, relatively little is known about the ecological and physiological constraints that may influence the development and maintenance of sensory systems. In the house finch (Carpodacus mexicanus) and many other bird species, carotenoid pigments are used to create colorful sexually selected displays, and their expression is limited by health and dietary access to carotenoids. Carotenoids also accumulate in the avian retina, protecting it from photodamage and tuning color vision. Analogous to plumage carotenoid accumulation, I hypothesized that avian vision is subject to environmental and physiological constraints imposed by the acquisition and allocation of carotenoids. To test this hypothesis, I carried out a series of field and captive studies of the house finch to assess natural variation in and correlates of retinal carotenoid accumulation and to experimentally investigate the effects of dietary carotenoid availability, immune activation, and light exposure on retinal carotenoid accumulation. Moreover, through dietary manipulations of retinal carotenoid accumulation, I tested the impacts of carotenoid accumulation on visually mediated foraging and mate choice behaviors. My results indicate that avian retinal carotenoid accumulation is variable and significantly influenced by dietary carotenoid availability and immune system activity. Behavioral studies suggest that retinal carotenoid accumulation influences visual foraging performance and mediates a trade-off between color discrimination and photoreceptor sensitivity under dim-light conditions. Retinal accumulation did not influence female choice for male carotenoid-based coloration, indicating that a direct link between retinal accumulation and sexual selection for coloration is unlikely. However, retinal carotenoid accumulation in males was positively correlated with their plumage coloration. Thus, carotenoid-mediated visual health and performance or may be part of the information encoded in sexually selected coloration.
ContributorsToomey, Matthew (Author) / McGraw, Kevin J. (Thesis advisor) / Deviche, Pierre (Committee member) / Smith, Brian (Committee member) / Rutowski, Ronald (Committee member) / Verrelli, Brian (Committee member) / Arizona State University (Publisher)
Created2011
Description
Identifying disease biomarkers may aid in the early detection of breast cancer and improve patient outcomes. Recent evidence suggests that tumors are immunogenic and therefore patients may launch an autoantibody response to tumor associated antigens. Single-chain variable fragments of autoantibodies derived from regional lymph node B cells of breast cancer patients were used to discover these tumor associated biomarkers on protein microarrays. Six candidate biomarkers were discovered from 22 heavy chain-only variable region antibody fragments screened. Validation tests are necessary to confirm the tumorgenicity of these antigens. However, the use of single-chain variable autoantibody fragments presents a novel platform for diagnostics and cancer therapeutics.
ContributorsSharman, M. Camila (Author) / Magee, Dewey (Mitch) (Thesis director) / Wallstrom, Garrick (Committee member) / Petritis, Brianne (Committee member) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor) / Virginia G. Piper Center for Personalized Diagnostics (Contributor) / Biodesign Institute (Contributor)
Created2012-12
Description
Time spent alone is a topic that has been studied in great detail, particularly the manner in which it is spent and the effect it has during the adolescent stage of life. Similarly, stress levels in adolescents have always been a topic of interest because of the effects they could have on the individual later in adulthood. Oddly enough however, the two areas of study have never been looked at in relation to one another. This study will look at different types of alone time as possible stressors in a community sample (N=82) of adolescents transitioning to college. The data on time alone and stress levels was collected through diary reports over a period of 3 days. The analysis only yielded significant effects for females and only for specific categories. It was found that females experience the lowest amount of perceived stress when they are alone and want to be alone, they have more negative affect when their desired environment differs from their current situation, and more positive affect in both the alone incongruence and not alone congruence situations. These results indicate that only women experience stress and affect changes when they encounter different congruent and incongruent environments.
ContributorsVanderwerf, Jennifer (Author) / Doane, Leah (Thesis director) / Knight, George (Committee member) / Arbona, P. Anita (Committee member) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor)
Created2012-12
Description
The purpose of my honors thesis project was to generate the tools needed for in vivo imaging by determining the optimal plasmid-fluorophore combination. To determine the optimal plasmid and fluorophore, asd plasmids were constructed with various promoters, origins of replications, and red fluorophores. The optimal asd plasmid for fluorescent in vivo imaging was determined by the plasmid stability, growth rate, and growth phase dependence on fluorescent intensity. The end goal is to be able to use the asd plasmid in vaccine strains for the purpose of in vivo imaging of the recombinant attenuated Salmonella vaccine (RASV).
ContributorsEudy, L. Adam (Author) / Curtiss, Roy (Thesis director) / Roland, Kenneth (Committee member) / Forbes, Stephen (Committee member) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor)
Created2012-12