Tag: Poster 27

Hold the Door! Preventing Mildew in a Shower Room

Presenters: Tyler Mavichien and Regan Greenhill

Mentor: Matt Hogan

AM Poster Presentation

Poster 27

When a sign stating to leave the door open after showers to prevent mildew was placed on the door to the shower room in a cam- pus residence hall, residents wondered why it was necessary especially because of the multiple air vents located in the shower room. The question formed from this observation and the basis of our case study was: would leaving the door to the shower room open lower the rate of humidity more than leaving the door closed? We tested the intake rate of the vents and measured the humidity the showers created with Hobo U12 Datalogger. After surveys of the residents were conducted to find the average length of the shower, 12.5 minutes, three scenarios were tested. First, running the shower for 12.5 minutes with the door closed the entire time and leaving the door closed 30 minutes after water has stopped. Second, running the shower for 12.5 minutes with the door closed the entire time then opening the door for 30 minutes after water has stopped. Third, a worst-case scenario of running all three shower heads at the hottest setting for 15 minutes with the door closed the entire time and leaving the door closed 40 minutes after water had stopped. Finally, a long term test was conducted over five day measuring regular usage. Our results showed that humidity levels did not stay above 60% for more than an hour, the level at which mildew starts to grow. Our case study proved the intake vents are effective in preventing mildew from growing and the added sign is unnecessary.

Deciduous Teeth Show Close Relationships Between Oreodont Genera (Eucrotaphus, Merycochoerus and Promerycochoerus)

Presenter : Kendra Walters

Mentor : Edward Davis

Major : Biology

Poster 27

Oreodonts lived during the Cenozoic Era, particularly from the Eocene to Miocene Epochs. They were abundant in the past but have no modern descendants. Classifying oreodonts is a difficult task because there is disagreement on the species, genus and subfamily classifications of many individual oreodont groups. The three genera of oreodonts we examined (Promerycochoerus, Merycochoerus, and Eucrotaphus) have experienced this problem and are divided between two to three different subfamilies. Our examination of the deciduous teeth of four individuals from these three genera found great morphological similarity, indicating a closer relationship than is currently recognized. We examined two individuals of Eucrotaphus trigonocephalus, one individual of Merycochoerus sp., and one of Promerycochoerus carrikeri from the collection at the University of California Museum of Paleontology. The deciduous premolars from all three genera are tellingly similar, varying only in size, and match previous descriptions of Promerycochoerus carrikeri. Simi- larities are especially evident in the last two deciduous premolars. These similar characters contradict the current subfamily divisions, indicating a close relationship between all three genera. We propose a re-division of oreodont subfamilies that reflects this close deciduous morphology. We also recognize synonymy of Promerycochoerus and Merycochoerus, as our examination primarily found size differences between them that we do not accept as genus-level distinctions.

CO2 Got Me Feeling So Blue?

Presenter: Lindsay Rasmussen

Co-Presenters: Katie Bushman, Parisa Motahari-asl

Mentor: Alison Kwok

Poster: 27

Major: Architecture 

This case study measures the carbon dioxide levels in the Architectural Design Studios of Pacific Hall, focusing on room 223. The current number of occupants in this room exceeds the original design intent; nevertheless, the original variable-air-volume ventilation system continues to be used. This case study investigates whether a larger occupancy number raises the carbon dioxide levels past the ventilation system’s capacity to function at ASHRAE Standards. For a contextual comparison a control room in a newly renovated building was also studied. The principal hypothesis for this case study is that the amount of CO2 in Room 223 of Pacific Hall exceeds the maximum levels as defined by ASHRAE Standard 62.1-2010. Three CO2 monitors were placed directly at the primary vent, at desk level, and outside at the air-intake system. CO2 levels were recorded at the same time for 30 minutes in 30-second increments. This experiment was repeated twice per room, once with high-occupancy and once with low-occupancy. Our results show that CO2 levels did not exceed maximum levels in either room. Instead of being an air quality issue, we found there to be a thermal comfort issue in Pacific Hall. However, due to the state of the building and its prior use as a chemical lab, we still believe there to be an air quality issue that we could not account for in this experiment. Carbon dioxide is measured as an indicator of building air quality; however, the results of our experiment lead us to question whether or not CO2 is an accurate representative of overall indoor air quality. This experiment serves as a strong foundation for further research into indoor air quality.

Rotational Properties of the Extraordinary Multi-tailed Asteroid P/2013 P5

Annika Gustafsson

Mentor: Scott Fisher, Physics

Poster: 27

Majors: Physics and Mathematics 

Observations made with the Hubble Space Telescope in September 2013 revealed that the asteroid known as P/2013 P5 appeared to have six comet-like tails. Jewitt et al. (2013) concluded that this extraordinary structure and activity cannot be explained by traditional near-surface ice sublimation or collision events ejecting particles from the asteroid’s surface. Instead, the most likely explanation is that this unusual object has been spun-up by solar radiation forces to a critical limit that resulted in the rotational disruption of the asteroid causing the unique six-tail structure. This interpretation predicts that the nucleus of this comet-like asteroid should be in rapid rotation as a result of spin- up caused by the solar radiation forces. In November 2013, Dr. Stephen Levine obtained broadband photometry of P/2013 P5 for a duration of 4 hours using Lowell Observatory’s 4.3-meter Discovery Channel Telescope with the Large Monolithic Imager to investigate the possibility of rapid rotation. After performing differential photometry on P/2013 P5, the resulting light curves were analyzed to search for periodicity of 2.2 hours, an easy indicator of rapid rotation. While the variation in the rotational light curve from these data was too small to be justifiable, morphological changes in the nucleus-coma system were observed.

Photoluminescence and Electronic Energy Structures of Exfoliated and CVD-Grown Single-Layer Molybdenum Disulfide

Presenter: Josiah Makinster

Faculty Mentor: Hailin Wang

Presentation Type: Poster 27

Primary Research Area: Science

Major: Physics

Funding Source: UROP Mini-Grant, University of Oregon, $1000

The electronic energy structures of exfoliated and chemical vapor deposition (CVD) grown single-layer Molybdenum Disulfide (MoS2) are investigated via photoluminescent spectroscopy to illuminate its potential in future semiconductor technology. Single-layer direct bandgap materials like MoS2 have applications in numerous areas, including light-emitting-diodes, flexible electronics, and solar cells, all of which will further advance through an understanding of its novel properties. Recently, it has been discovered that MoS2 is a material that can be cleaved into a microscopic sheet that is a single molecular layer thick, and shows novel physical properties that bulk MoS2 does not, including a strong photoluminescence (PL) that only emerges in the single-layer material due to a change in the electronic energy structure from an indirect bandgap to a direct bandgap. Here, PL spectra of exfoliated MoS2 and CVD-grown MoS2 are compared to assess the quality of the CVD-grown material, which tends to have a lower quality than exfoliated MoS2. Also, the PL spectrum of single-layer MoS2 is measured at cryogenic temperatures, because higher temperatures cause an increase in non-radiative recombination of excitons, which can potentially obscure important spectral features. We find that another PL peak emerges in the spectrum, indicating a high dependence of the electronic energy structure on temperature. All in all, theoretical results from literature that propose that single-layer MoS2 is a direct bandgap material are confirmed.

Dual-Task Gait Stability Assessment Utilizing a 180° Turn

Presenter(s): Emma Silverman − Human Physiology

Faculty Mentor(s): Will Pitt, Li-Shan Chou

Poster 27

Research Area: Biomechanics

The purpose of this study is to determine if a 180° turn is a useful metric for assessment of dynamic instability. 15 healthy subjects were recruited for this study. Angular velocity around a vertical axis was measured with a sensor over the L5 vertebrae. Utilizing that data, total medial-lateral center of mass deviation during a 180o turn was compared between conditions. All subjects performed a walking task at a self-selected pace, which consisted of an 8m walk, a 180 degree turn, and a return to the starting position. This walking task was performed under three different conditions (single-task walking and two dual-task conditions), in two different environments (laboratory and a hallway stimulating a medical clinic), over two testing days (approximately 7-10 days apart), and by two different raters. Currently, data collection has been completed. Data is currently being processed and thorough statistical analysis will begin shortly. Initial data analysis suggests a trend for significance (p=0.072), indicating that a 180° turn may be an additional useful metric for assessment of dynamic instability.

The effects of leucine, arginine and lysine, and HMB stimulation of anabolic and catabolic mechanisms on myoblasts

Presenter(s): Lillian Wheary

Co Presenter(s): Sam Kirby, Nick Belair

Faculty Mentor(s): Hans Dreyer & Doug Foote

Poster 27

Session: Sciences

Total knee arthroplasty (TKA) procedures are projected to increase nearly seven-fold to 3.4 million per year in the U.S. by 2030. Nearly all patients undergoing this surgery experience some degree of muscle loss during the first two weeks after surgery. Although effective at eliminating osteoarthritic pain, muscle atrophy and functional deficits persist. Essential amino acid (EAA) supplementation has been successful used by us in mitigating muscle atrophy after TKA. To understand how EAAs work at the cellular level, we isolated myoblasts from biopsies. Our goal was to model the cellular responses to anabolic stimuli using cell culture methods. Our objectives were: 1) isolate myoblasts from biopsies with >80% purity, 2) measure changes in anabolic mTORC1 response to anabolic amino acids (leucine, lysine and arginine (LRK)) ± insulin, and 3) measure changes to the leucine metabolite hydroxy-beta-methylbutyrate (HMB). Cells were seeded and myogenic purity confirmed via immunocytochemistry (ICC). Phosphorylation status of anabolic and catabolic signaling were determined. Preliminary results: isolating myoblasts from older muscle is more difficult than young controls. LRK+I produced a significant increase in rpS6 and Akt phosphorylation while no change was detected when myoblasts were incubated with HMB. Additional research is needed to refine our isolation methods and to better understand the mechanism(s) through which amino acids can help to maximally preserve muscle mass after common orthopedic procedures in older adults. If successful, recovery strategies such as amino acid supplementation will improve functional mobility following surgery and enhance long-term quality of life for these older individuals.