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- All Subjects: Biology
- Creators: School of Life Sciences
- Status: Published
Description
I argued that the development of the Anterior Inferior Iliac Spine (AIIS), an entirely novel trait unique to the hominin pelvis, signaled a critical transformation from facultative (occasional) to obligate (exclusive) bipedality. The species that were considered included Homo sapiens, Australopithecus afarensis (Lucy), Ardipithecus ramidus (Ardi) and Pan troglodytes (chimpanzee); Ar. ramidus is believed to have been a facultative biped while both A. afarensis and H. sapiens were/are obligate bipeds, a stark contrast from the upright Bent-Hip Bent-Knee gait seen in chimpanzees, an organism that lacks an AIIS. It was found that the AIIS served a significant function in the advent of bipedality from Pan to Ardi because it allowed higher attachment for the rectus femoris muscle, a crucial knee extensor; however it is not heavily implicated in the transformation from facultative to obligate bipedality. Moreover, the appearance of the AIIS, first seen in Ardi, likely occurred following the lumbosacral changes that positioned the hominin body in an upright position so that the body's center of mass remained balanced over its supporting base. This provided the framework necessary to further select for organisms that had the AIIS and could walk upright, which perpetuated this change in the hominin lineage.
ContributorsGalibov, Michael (Author) / Kimbel, William (Thesis director) / Jacobs, Mark (Committee member) / School of Life Sciences (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Learning student names has been promoted as an inclusive classroom practice, but it is unknown whether students value having their names known by an instructor. We explored this question in the context of a high-enrollment active-learning undergraduate biology course. Using surveys and semistructured interviews, we investigated whether students perceived that instructors know their names, the importance of instructors knowing their names, and how instructors learned their names. We found that, while only 20% of students perceived their names were known in previous high-enrollment biology classes, 78% of students perceived that an instructor of this course knew their names. However, instructors only knew 53% of names, indicating that instructors do not have to know student names in order for students to perceive that their names are known. Using grounded theory, we identified nine reasons why students feel that having their names known is important. When we asked students how they perceived instructors learned their names, the most common response was instructor use of name tents during in-class discussion. These findings suggest that students can benefit from perceiving that instructors know their names and name tents could be a relatively easy way for students to think that instructors know their names. Academic self-concept is one's perception of his or her ability in an academic domain compared to other students. As college biology classrooms transition from lecturing to active learning, students interact more with each other and are likely comparing themselves more to students in the class. Student characteristics, such as gender and race/ethnicity, can impact the level of academic self-concept, however this has been unexplored in the context of undergraduate biology. In this study, we explored whether student characteristics can affect academic self-concept in the context of a college physiology course. Using a survey, students self-reported how smart they perceived themselves in the context of physiology compared to the whole class and compared to the student they worked most closely with in class. Using logistic regression, we found that males and native English speakers had significantly higher academic self-concept compared to the whole class compared with females and non-native English speakers, respectively. We also found that males and non-transfer students had significantly higher academic self-concept compared to the student they worked most closely with in class compared with females and transfer students, respectively. Using grounded theory, we identified ten distinct factors that influenced how students determined whether they are more or less smart than their groupmate. Finally, we found that students were more likely to report participating less than their groupmate if they had a lower academic self-concept. These findings suggest that student characteristics can influence students' academic self-concept, which in turn may influence their participation in small group discussion.
ContributorsKrieg, Anna Florence (Author) / Brownell, Sara (Thesis director) / Stout, Valerie (Committee member) / Cooper, Katelyn (Committee member) / School of Life Sciences (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The purpose of our study was to evaluate whether viewing videos of dogs had an effect on the stress response of college students. While there is strong support in the literature for demonstrating the beneficial effect of human-canine interactions on human stress indicators, there is very little to no literature on whether or not this phenomenon translates across a digital medium. We hypothesized that when exposed to a video of golden retriever puppies after a stress-inducing task, an individual would experience an increase in blood pressure recovery rate and a decline in perceived stress. In order to study this, we put together several surveys to test our participants' perceived stress, and we measured blood pressure several times in order to obtain a physiological measure of stress. Additionally, in order to produce a guaranteed stress response in our participants, we gave them 2 minutes to prepare a 4 minute video-recorded speech that they were not made aware of prior to entering the testing facility. After the speech task, the experimental group quietly viewed a pleasant 4 minute video containing imagery of dogs, while the control group sat silently for the same duration of time. During this time, the control group was asked to mentally review their performance and to focus intently on the feelings they experienced while giving their speech. Through these measures we found a significant recovery rate in systolic blood pressure and a trending difference between groups for the decline in negative affect. The data demonstrated that the experimental group had blood pressure levels that were significantly closer to their baseline levels when compared to the control group, whose blood pressure did not decline at the same rate. Additionally, the experimental group experienced a higher level of change in negative affect when asked to self-report their level of stress before the speech task and after the conditional recovery period. Interestingly, these findings can be applied to recent literature suggesting that systolic blood pressure is the most important factor of cardiac health to consider when assessing an individual for risk of heart disease or cardiac arrest. While the sample size of this study was small, the significant reduction in systolic blood pressure within the experimental group could indicate the possible efficacy of utilizing digital media containing imagery of canines as a form of therapy for systolically-hypertensive individuals as a means of managing their condition.
ContributorsDiModugno, Maria (Co-author) / Barbera, Joseph (Co-author) / Luecken, Linda (Thesis director) / Lemery-Chalfant, Kathryn (Committee member) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Bexarotene (Bex) is a FDA-approved drug used to treat cutaneous T-cell lymphoma (CTCL). It binds with high affinity to the retinoid-X-receptor (RXR), a nuclear receptor implicated in numerous biological pathways. Bex may have the potential to attenuate estrogenic activity by acting as an estrogen receptor alpha (ERα) signaling antagonist, and can therefore be used to treat ERα-positive cancers, such as breast cancer. Using dual luciferase reporter assays, real-time qRT-PCR, and metabolic proliferation assays, the anti-estrogenic properties of Bex were ascertained. However, since Bex produces numerous contraindications, select novel RXR drug analogs were also evaluated. Results revealed that, in luciferase assays, Bex could significantly (P < 0.01) inhibit the transcriptional activity of ERα, so much so that it rivaled ER pan-antagonist ZK164015 in potency. Bex was also able to suppress the proliferation of two breast cancer cell models, MCF-7 and T-47D, and downregulate the expression of an estrogen receptor target gene (A-myb), which is responsible for cell proliferation. In addition, novel analogs A30, A33, A35, and A38 were evaluated as being more potent at inhibiting ERE-mediated transcription than Bex at lower concentrations. Analogs A34 and A35 were able to suppress MCF-7 cell proliferation to a degree comparable to that of Bex. Inhibition of T-47D cell proliferation, by contrast, was best achieved by analogs A34 and A36. For those with ERα – positive breast cancer who are refractory to current chemotherapeutics used to treat breast cancer, Bex and its analogs may prove to be useful alternative options.
ContributorsBains, Supreet (Author) / Jurutka, Peter (Thesis director) / Hackney Price, Jennifer (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Student to Student: A Guide to Anatomy is an anatomy guide written by students, for students. Its focus is on teaching the anatomy of the heart, lungs, nose, ears and throat in a manner that isn't overpowering or stress inducing. Daniel and I have taken numerous anatomy courses, and fully comprehend what it takes to have success in these classes. We found that the anatomy books recommended for these courses are often completely overwhelming, offering way more information than what is needed. This renders them near useless for a college student who just wants to learn the essentials. Why would a student even pick it up if they can't find what they need to learn? With that in mind, our goal was to create a comprehensive, easy to understand, and easy to follow guide to the heart, lungs and ENT (ear nose throat). We know what information is vital for test day, and wanted to highlight these key concepts and ideas in our guide. Spending just 60 to 90 minutes studying our guide should help any student with their studying needs. Whether the student has medical school aspirations, or if they simply just want to pass the class, our guide is there for them. We aren't experts, but we know what strategies and methods can help even the most confused students learn. Our guide can also be used as an introductory resource to our respective majors (Daniel-Biology, Charles-Speech and Hearing) for students who are undecided on what they want to do. In the future Daniel and I would like to see more students creating similar guides, and adding onto the "Student to Student' title with their own works... After all, who better to teach students than the students who know what it takes?
ContributorsKennedy, Charles (Co-author) / McDermand, Daniel (Co-author) / Kingsbury, Jeffrey (Thesis director) / Washo-Krupps, Delon (Committee member) / Department of Speech and Hearing Science (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The International Space Station (ISS) utilizes recycled water for consumption, cleaning and air humidity control. The Environmental Control and Life Support Systems (ECLSS) have been rigorously tested at the NASA Johnson Space Center. Despite the advanced engineering of the water recovery system, bacterial biofilms have been recovered from this potable water source. Microbial contamination of potable water poses a potential threat to crew members onboard the ISS. Because astronauts have been found to have compromised immune systems, bacterial strains that would not typically be considered a danger must be carefully studied to better understand the mechanisms enabling their survival, including polymicrobial interactions. The need for a more thorough understanding of the effect of spaceflight environment on polymicrobial interactions and potential impact on crew health and vehicle integrity is heightened since 1) several potential pathogens have been isolated from the ISS potable water system, 2) spaceflight has been shown to induce unexpected alterations in microbial responses, and 3) emergent phenotypes are often observed when multiple bacterial species are co- cultured together, as compared to pure cultures of single species. In order to address these concerns, suitable growth media are required that will not only support the isolation of these microbes but also the ability to distinguish between them when grown as mixed cultures. In this study, selective and/or differential media were developed for bacterial isolates collected from the ISS potable water supply. In addition to facilitating discrimination between bacteria, the ideal media for each strain was intended to have a 100% recovery rate compared to traditional R2A media. Antibiotic and reagent susceptibility and resistance tests were conducted for the purpose of developing each individual medium. To study a wide range of targets, 12 antibiotics were selected from seven major classes, including penicillin, cephalosporins, fluoroquinolones, aminoglycosides, glycopeptides/lipoglycopeptides, macrolides/lincosamides/streptogramins, tetracyclines, in addition to seven unclassified antibiotics and three reagents. Once developed, medium efficacy was determined by means of growth curve experiments. The development of these media is a critical step for further research into the mechanisms utilized by these strains to survive the harsh conditions of the ISS water system. Furthermore, with an understanding of the complex nature of these polymicrobial communities, specific contamination targeting and control can be conducted to reduce the risk to crew members. Understanding these microbial species and their susceptibilities has potential application for future NASA human explorations, including those to Mars.
ContributorsKing, Olivia Grace (Author) / Nickerson, Cheryl (Thesis director) / Barrila, Jennifer (Committee member) / Ott, Mark (Committee member) / School of Sustainability (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
Rhesus (Macaca mulatta) and cynomolgus (M. fascicularis) macaques are the most commonly used nonhuman primate models in biomedical research. It is therefore critical to correctly infer each study animal's ABO blood group phenotype to prevent fatal transfusion- and transplantation-induced immune responses. While most macaques can be efficiently and accurately phenotyped using a DNA-based assay, we have identified some animals that are unable to be classified as type A, B, or AB and therefore exhibit an indeterminate phenotype. The purpose of this study was to develop a protocol for resolving indeterminate blood group phenotypes and consequently determine if these animals do indeed belong to an O blood phenotype. We attempted both direct and cloning-based sequencing of 21 animals phenotyped as A, B, AB, or indeterminate in order to assess variation at the functional mutation site in exon 7 of the macaque ABO gene. Although direct-from-PCR Sanger sequencing was unable to generate reliable sequence results, our cloned plasmid protocol yielded high quality sequences consistent with known blood group-specific alleles and as such can be used to identify informative polymorphisms at this locus.
ContributorsVizor, Choice Popsira (Author) / Kanthaswamy, Sreetharan (Thesis director) / Oldt, Robert (Committee member) / Department of Information Systems (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
As a biology major, many of my classes have included studying the fundamentals of genetics or investigating the way genetics influence heritability of certain diseases. When I began taking upper-division psychology courses, the genetic factors of psychological disorders became an important part of the material. I was exposed to a new idea: that genes were equally important in studying somatic diseases as they were to psychological disorders. As important as genetics are to psychology, they are not part of the required courses for the major; I found many of my peers in psychology courses did not have a grasp on genetic fundamentals in the same way biology majors did. This was a disconnect that I also found in my own life outside the classroom. Growing up, my mother consistently reminded me to limit my carbs and watch my sugars. Diabetes was very prevalent in my family and I was also at risk. I was repeatedly reminded of my own genes and the risk I faced in having this biological disorder. However, my friend whose father was an alcoholic did not warn her in the same way. While she did know of her father's history, she was not warned of the potential for her to become an alcoholic. While my behavior was altered due to my mother's warning and my own knowledge of the genetic risk of diabetes, I wondered if other people at genetic risk of psychological disorders also altered their behavior. Through my thesis, I hope to answer if students have the same perceived genetic knowledge of psychological diseases as they do for biological ones. In my experience, it is not as well known that psychological disorders have genetic factors. For example, alcohol is commonly used by college students. Alcohol use disorder is present in 16.2% of college aged students and "40-60% of the variance of risk explained by genetic influences." (DSM V, 2013) Compare this to diabetes that has "several common genetic variants that account for about 10% of the total genetic effects," but is much more openly discussed even though it is less genetically linked. (McVay, 2015)This stems from the stigma/taboo surrounding many psychological disorders. If students do know that psychological disorder are genetically influenced, I expect their knowledge to be skewed or inaccurate. As part of a survey, I hope to see how strong they believe the genetic risk of certain diseases are as well as where they gained this knowledge. I hypothesize that only students with a background in psychology will be able to correctly assign the genetic risk of the four presented diseases. Completing this thesis will require in-depth study of the genetic factors, an understanding of the way each disease is perceived and understood by the general population, and a statistical analysis of the survey responses. If the survey data turns out as I expect where students do not have a strong grasp of diseases that could potentially influence their own health, I hope to find a way to educate students on biological and psychological diseases, their genetic risk, and how to speak openly about them.
ContributorsParasher, Nisha (Author) / Amdam, Gro (Thesis director) / Toft, Carolyn Cavaugh (Committee member) / Ostwald, Madeleine (Committee member) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Sleep is imperative for health and wellness with direct impacts on brain function, physiology, emotional well-being, performance and safety when compromised. Adolescents and young adults are increasingly affected by factors affecting the maintenance of regular sleep schedules. College and university students are a potentially vulnerable population to sleep deprivation and sleep insufficiency. Possible factors that could contribute to poor sleep hygiene include, but are not limited to, academic pressures, social activities, and increased screen time. Arguably, students are still experiencing bone mineralization, until the age of 30 or even 40 years old, which makes it more important to understand the effects that altered sleep patterns could have on continued development of bone health. It is our understanding that to date, studies assessing the risk of sleep insufficiency on bone mineral density in college students have not been conducted. We hypothesized that college-aged students, between the ages of 18-25 years, with shorter sleep durations, greater sleep schedule variability, and poorer sleep environments will have significantly lower bone mineral density. ActiGraph monitoring, via a wrist ActiWatch was used to quantitatively measure sleep habits for up to 7 consecutive days. During the week-long study participants also captured their self-reported sleep data through the use of a sleep diary. Participants were measured one time within the study for bone mineral density of the lumbar spine and total hip through a dual energy x-ray absorptiometry. This was a preliminary analysis of a larger cross-sectional analysis looked at 17 participants, of which there were 14 females and 3 males, (n=5, 1 and 11 Hispanic, Black and White, respectively). The mean age of participants was 20.8±1.7 y with an average BMI of 22.9±3.2 kg/m2. ActiWatch measurement data showed a mean daily sleep duration of participants to be 437.5 ± 43.1 (372.5 – 509.4) minutes. Mean sleep efficiency (minutes of sleep divided by minutes of time in bed) and mean number of awakenings were 87.4±4.3 (75.4-93.4) minutes and 32.1±6.4 (22.3-42.7) awakenings, respectively. The median time for wake after sleep onset (WASO) was 34.5±10.5 (18.3-67.4) minutes. The mean bone mineral density (BMD) for the hips was 1.06±0.14 (0.81-1.28) g/cm2 with a mean BMD of the lumbar spine being 1.24±0.12 (0.92-1.43) g/cm2. Age-matched Z-scores of the hips was 0.31±0.96 (-1.6-2.1) and lumbar spine was 0.53 (IQR: 0.13, 0.98; -2.25-1.55). Neither sleep duration nor sleep efficiency was significantly correlated to BMD of either locations. While WASO was positively associated with hip and spine BMD, this value was not statistically significant in this population. Overall, associations between sleep and BMD of the femur and spine were not seen in this cohort. Further work utilizing a larger cohort will allow for control of covariates while looking for potential associations between bone health, sleep duration and efficiency.
ContributorsEsch, Patricia Rose (Author) / Whisner, Corrie (Thesis director) / Petrov, Megan (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Dire wolves have recently risen to fame as a result of the popular television program Game of Thrones, and thus many viewers know dire wolves as the sigil and loyal companions of the Stark house. Far fewer recognize dire wolves by their scientific name, Canis dirus, or understand the population history of this ‘fearsome wolf’ species that roamed the Americas until the megafaunal mass extinction event of the Late Pleistocene. Although numerous studies have examined the species using morphological and geographical methods, thus far their results have been either inconclusive or contradictory. Remaining questions include the relationships dire wolves share with other members of the Canis genus and the internal structure of their populations. Advancements in ancient DNA recovery methods may make it possible to study dire wolf specimens at the molecular level for the first time and may therefore prove useful in clarifying the answers to these questions. Eighteen dire wolf specimens were collected from across the United States and subjected to ancient DNA extraction, library preparation, amplification and purification, bait preparation and capture, and next-generation sequencing. There was an average of 76.9 unique reads and 5.73% coverage when mapped to the Canis familiaris reference genome in ultraconserved regions of the mitochondrial genome. The results indicate that endogenous ancient DNA was not successfully recovered and perhaps ancient DNA recovery methods have not advanced to the point of retrieving informative amounts of DNA from particularly old, thermally degraded specimens. Nevertheless, the ever-changing nature of ancient DNA research makes it vital to continually test the limitations of the field and suggests that ancient DNA recovery methods will prove useful in illuminating dire wolf population history at some point in the future.
ContributorsSkerry, Katherine Marie (Author) / Stone, Anne (Thesis director) / Amdam, Gro (Committee member) / Larson, Greger (Committee member) / School of Human Evolution and Social Change (Contributor) / School of Nutrition and Health Promotion (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05