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The ringtail (Bassariscus astutus), a member of the Procyonidae, is capable of 180 degrees of hindlimb reversal during headfirst descent down a vertical substrate. The goal of this study was to determine the presence or absence of myological adaptations related to hindlimb reversal in the ringtail. Data for B. astutus are presented, including muscle weights and muscle maps ascertained from the dissection of four hindlimbs. Data from the current study were compared to published accounts of other species capable of hindlimb reversal, including procyonids (raccoon, coati, kinkajou, olingo), a mustelid (marten), palm civet, mongoose, tree squirrel, common tree shrew, and slow loris. Muscle mass data from this study demonstrate that the hip adductors of scansorial mammals are significantly more robust than those of terrestrial mammals, indicating a myological adaptation for climbing, but not necessarily hindlimb reversal. Among hindlimb reversers, the majority exhibit one belly of m. sartorius, the presence of m. extensor digiti I longus, and a fibular origin for m. fibularis longus. These characteristics indicate an emphasis on hip extension, ankle plantarflexion, and pes inversion. However, these characteristics are more likely due to phylogeny than hindlimb reversal because of their presence in closely-related non-reversers. Additional data on families outside of Carnivora may help determine if these myological traits are indeed due to phylogeny. Other myological data, such as moment arms and cross sectional areas, may provide evidence of adaptations for hindlimb reversal.
ContributorsLiu, Margaret Chuan (Author) / Fisher, Rebecca (Thesis director) / Hinrichs, Richard (Committee member) / Kusumi, Kenro (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
Multiple myeloma is a genetically heterogeneous disease, which can be divided into several genetic subtypes based upon gene expression profiles and chromosomal abnormalities. Unlike older techniques employed in myeloma research, such as cytogenetics, FISH, and microarray technologies, RNA sequencing offers a unique approach to examine the aforementioned genetic characteristics in that it allows for gene expression profiling and the detection of novel fusion transcripts arising from chromosomal rearrangements. This study utilized RNA sequencing to analyze the transcriptomes of 84 multiple myeloma patients and 69 human myeloma cell lines. FCHSD2 was found to be involved in five novel fusion events along with known oncogenes, MMSET and MYC, as well as three previously unreported genes in myeloma, including CHMP4B, NCF2, and CARNS1. An analysis of FCHSD2 expression within myeloma cell lines indicated that it is highly expressed in comparison to other tissues, suggesting that FCHSD2 translocations could lead to promoter replacement events in which the expression of partnering genes is dysregulated. The presence of the five FCHSD2 hybrid transcripts was confirmed by reverse transcription-PCR and Sanger sequencing. Overexpression of the FCHSD2 fusion transcripts in HEK293 cells resulted in the production of N-terminally truncated fusion partner proteins and a novel FCHSD2-CARNS1 fusion protein.
ContributorsMurray, Christopher William (Author) / Wilson-Rawls, Jeanne (Thesis director) / Carpten, John (Committee member) / Keats, Jonathan (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
Morbid obesity is associated with cardiovascular and metabolic disorders. A major contributor to the pathogenesis of these diseases is impaired vasodilation resulting from elevated reactive oxygen species (ROS). This is because certain ROS such as superoxide are raised with obesity and scavenge the endogenous vasorelaxant nitric oxide, resulting in hypertension. The objective of this study was to measure the ability of genistein to quench superoxide in the vasculature of ob/ob mice, an animal model of obesity and type 2 diabetes. Genistein is an isoflavonic phytoestrogen naturally found in soy products. While genistein has documented antioxidant and anti-inflammatory properties, it is not known whether this protects the vasculature from oxidative stress. Genistein was hypothesized to reduce superoxide in arteries from female ob/ob mice. The superoxide indicator dihydroethidium (DHE) [2µL/mL HEPES buffer] was added to isolated aortae and mesenteric arteries from mice fed either a control (standard rodent chow containing 200-300 mg genistein/kg) or genistein-enriched (600mg genistein/kg rodent chow) diets for 4 weeks. Frozen tissues sections were collected onto glass microscope slides and examined using confocal microscopy. Contrary to the hypothesis, a diet containing twice the amount of genistein found in standard chow did not significantly reduce superoxide concentrations in aortae (p=0.287) or mesenteric arteries (p=0.352). Superoxide dismutase, an antioxidant enzyme that breaks down superoxide, was significantly upregulated in the genistein-enriched diet group (p=0.004), although this elevation did not promote the breakdown of superoxide. In addition, the inflammatory marker iNOS was not downregulated in the genistein-enriched diet group (p>0.05). The results indicate that high amounts of isoflavones, like genistein, may not exhibit the purported antioxidant effects in the vasculature of obese or diabetic subjects. Further studies examining arteries from ob/ob mice fed a genistein-free diet are needed to elucidate the true effects of genistein on oxidative stress.
ContributorsSimperova, Anna Marie (Co-author) / Al-Nakkash, Layla (Co-author) / Ricklefs, Kristin (Co-author) / Faust, James J. (Co-author) / Sweazea, Karen L. (Co-author) / Sweazea, Karen (Thesis director) / Gonzales, Rayna (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / T. Denny Sanford School of Social and Family Dynamics (Contributor)
Created2014-05
Description
This study examines the one month retention of executive function benefits gained by adolescents with Down syndrome after an 8-week aerobic exercise intervention. Sixteen participants were randomly divided between voluntary (VC) (i.e., self-selected cadence) and assisted (AC) (i.e., 30% faster than self-selected cadence accomplished by a motor) cycling groups, with one participant used as a control (NC). Both cycling groups rode a stationary bicycle, for 30 minutes, three times a week, for eight weeks. At the beginning (i.e., pretest) and end (posttest) of the 8-week session, three executive functions including: set-switching, inhibition, and cognitive planning, were tested. Approximately one month after the posttest, all participants underwent the cognitive testing again. The results showed that for the AC group cognitive planning improved after eight weeks of assisted cycling and these improvements were maintained after one month of no cycling. However, no significant differences were found between the cycling groups for our measure of inhibition. Set-switching appeared to be improved by both types of exercise, rather than only assisted, but the improvements were not maintained during the one month retention period for either group. Thus, our results suggest that Assisted Cycling causes potentially permanent changes in the brain in regards to cognitive planning.
ContributorsRichter, Madeline B. (Author) / Ringenbach, Shannon (Thesis director) / Amazeen, Eric (Committee member) / Maraj, Brian (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
The nonmedical use of prescription ADHD medications by American college students for the purpose of enhancing academic performance has been well-documented for more than a decade. A closer look at this trend through the lens of biomedicalization theory shows us that this behavior, which is often dismissed as a simple abuse of the system by deviant young people, is consistent with broader trends in post-modern medicine and health. The goal of this project was to describe the biomedicalization of studying by illustrating the historical, sociocultural, and politico-economic roots of nonmedical stimulant use by college students in the United States. An online survey was administered to students at ASU and responses from students studying in the College of Liberal Arts and Sciences (n=233) were analyzed. A 12.4% lifetime prevalence of illicit stimulant use was found among the sample population. Thematic analysis was performed on students' open-ended commentary and several themes related to the biomedicalization framework were uncovered including Necessity, Identity, Inextricability from academia, and Trust in the system. Through these themes it was found that many of the theorized transitions of biomedicalization were visible in the data set, confirming the idea that nonmedical stimulant use is embedded in the complex network of processes that represents post-modern medicine today.
ContributorsStevenson, Christine Renee (Author) / Brian, Jennifer (Thesis director) / Robert, Jason (Committee member) / Caniglia, Guido (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2014-05
Description
Ephemeral and intermittent streams are valuable sources of surface water support in the arid ecosystems of the Southwestern United States. These streams account for over 80% of the streams in the American Southwest and their importance has been indicated in many studies. Ephemeral and intermittent streams support a wide range of plant and animal species in both continuous and episodic fashions. This study aimed to gain a better understanding of the relationship between streamflow permanence and patterns of biomass and secondary production of the riparian fauna these ecosystems support. This was accomplished through a yearlong survey in the Huachuca Mountains of Southeastern, Arizona where macroinvertebrates were collected at various sites along a gradient of streamflow permanence before, during, and after the three month monsoon season that supplies most of the annual rainfall in this region. The results of my surveys indicate that 1) Sites characterized by low streamflow permanence were more responsive to changes in precipitation than sites characterized by relatively high streamflow permanence 2) In ephemeral streams, there is a significant peak in terrestrial macroinvertebrate production and biomass both during and after the monsoon season 3) streamflow permanence may convey consistent but not exceptional secondary production whereas seasonality in rainfall may convey exceptional but episodic secondary production—more so in sites where streamflow is not consistent.
ContributorsMcCartin, Michael Patrick (Author) / Sabo, John (Thesis director) / Stromberg, Juliet (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
This thesis aims to address the ethics of keeping the big cats, such as lions, tigers, and leopards, in zoos. It is a practice that has generated some controversy in light of scientific studies reporting stress among wide-ranging animals in captive enclosures, as well as in the context of wider discussions in animal welfare and conservation ethics in zoos. A driving question for this project, therefore, was "What are the arguments for and against keeping large felids in zoos/captivity?" This thesis examines the historical and current ethical approaches to evaluating the ethics of maintaining big cats in zoos. Due to many of the big cat species listed as endangered species on the IUCN redlist, the species-centered approach to zoo ethics is becoming the common viewpoint, and, as a result, zoos are deemed ethical because of their contribution to ex situ conservation practices. Further, the ethical arguments against zoos are minimized when the zoos provide suitable and appropriate enclosures for their large felids. Of course, not all zoos are created equal; the ethics of zoos need to be evaluated on a case-by-case basis, but in general, it is ethical to maintain big cats in zoos.
ContributorsZeien, Krista Marie (Author) / Minteer, Ben (Thesis director) / Smith, Andrew (Committee member) / Ellison, Karin (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
Conservation is a complicated entity consisting of a multitude of professional fields including social issues, cultural issues, and physical science. This thesis evaluates the positive and negative aspects of two broad types of conservation: top down fortress conservation and bottom up community-based conservation. Fortress conservation has many negative aspects, such as displacing human communities and preventing utilization of resources. However, it also has positive aspects, such as preventing the destruction of delicate ecosystems and slowing down extinctions. Community-based conservation is more inclusive and focuses on including the indigenous populations located within the proposed conservation site in the decision-making process. Its negatives include having an anthropocentric goal instead of valuing nature's intrinsic values. Understanding the differences inherent in these two methods is necessary in order to implement a conservation network with the highest chance for success.
ContributorsFink, Laurel Berylline (Author) / Smith, Andrew (Thesis director) / Collins, James (Committee member) / Minteer, Ben (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
In 2007, the Center for Biological Diversity (CBD) petitioned the United States Fish and Wildlife Service (USFWS) and the California Department of Fish and Wildlife (CDFW) to list the American pika (Ochotona princeps) as an endangered species. After several petition denials, the petition was evaluated during both 90-day, and 12-month reviews. Ultimately, both petitions were denied and the pika was not given protection under the Endangered Species Act (ESA). During the petitioning years, 2007 through 2013, there were many newspaper publications, press releases, and blog entries supporting the listing of the pika. Information published by these media ranged from misleading, to scientifically inaccurate. The public was swayed by these publications, and showed their support for listing the pika during the public comment period throughout the 12-month status review in California. While the majority of the public comments were in favor of listing the pika, there were a few letters that criticized the CBD for making a poster child out of a "cute" species. During the 12-month status review, the CDFW contacted pika experts and evaluated scientific literature to gain an understanding of the American pika's status. Seven years after the original petition, the CDFW denied listing the pika on the grounds that the species is not expected to become extinct in the next few decades. This case serves as an example where a prominent organization, the CBD, petitions to list a species that does not warrant protection. Their goal of making the pika the face of climate change failed when species was examined.
ContributorsBasso, Samantha Joy (Author) / Smith, Andrew (Thesis director) / Minteer, Ben (Committee member) / Angilletta, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
The NCAA recently declared sickle cell trait (SCT) to be a risk factor for sudden illness and death among student athletes. Fetal hemoglobin (HbF) concentration in adults is negatively correlated with disease severity in sickle cell anemia, although its effect on SCT is not fully understood and the concentration is found to have high variability across populations. Two single nucleotide polymorphisms (SNPs) at the human beta globin gene cluster, rs7482144 and rs10128556, contribute to the heritable variation in HbF levels and are associated with increased HbF concentrations in adults. A sample population of NCAA football student athletes was genotyped for these two polymorphisms, and their allele frequencies were compared to those of other populations. The minor allele of both polymorphisms had allele frequencies of 0.091 in the sample population, which compared closely with other populations of recent African heritage but was significantly different from European populations. The results of this study will be included in a larger study to predict whether these among other polymorphisms can be used as markers to predict susceptibility to heat-related emergencies in NCAA student athletes with SCT, although the small sample size will delay this process until participation in the study increases. Since both rs7482144 and rs10128556 exhibit high levels of linkage disequilibrium, and as their contributions to the heritable variability of HbF concentrations tend to differ greatly between populations of different ancestry, further investigations should be aimed at distinguishing between the effects of each SNP in African American, European, and other populations represented in NCAA football before conclusions can be drawn as to their practical use as genetic markers of heat susceptibility in student athletes with SCT.
ContributorsGrieger, Ryan Wayne (Author) / Stone, Anne C. (Thesis director) / Rosenberg, Michael (Committee member) / Madrigal, Lorena (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05