Category: Poster Presentation

Exploring the effect of bacterial signaling pathways on zebrafish neuro-immune development

Presenter: Dana Zaidan – Neuroscience

Faculty Mentor(s): Joseph Bruckner, Judith Eisen

Session: (In-Person) Poster Presentation

The gut microbiota has been linked to human health and development. We found that the gut microbiota is required for normal zebrafish social behavior, but how it influences the brain development required for social behavior is not well understood. We previously identified a population of zebrafish forebrain neurons that are also required for normal social behavior. By raising zebrafish “germ-free”, we found that the microbiota is required for normal forebrain neuronal arborization.

Microglia are brain-resident immune cells that remodel neurons and are excellent candidates for mediating interactions between the microbiota and the brain. We previously discovered that the microbiota promotes forebrain microglial abundance. We also found that neuronal arborization and microglial abundance are restored in germ-free fish after colonization with several different zebrafish-associated bacterial strains, suggesting that the microbiota might influence social neurodevelopment by a mechanism common to many bacteria. One pathway we explored involves a class of host proteins that receive bacterial signals called the Toll-like receptor (TLR) proteins. We also explored if and how proteins present in bacterial cell walls are sensed by host mechanisms in the brain. Identifying the signaling components that link the microbiota and brain development will clarify our understanding of how host-microbe interactions can influence human health.

Determining How S100A9 Activates TLR4 Using Evolutionary and Biochemical Approach

Presenter: Jiayi Yin – Biochemistry

Faculty Mentor(s): Mike Harms, Sophia Phillips

Session: (In-Person) Poster Presentation

The immune system activates inflammation in response to both foreign pathogens and internal damage. Dysregulated inflammation can lead to many chronic diseases such as arthritis, inflammatory bowel disease, and some cancers. S100A9, a protein expressed in immune cells, has been found in high concentration in inflamed tissue of many of these chronic diseases. S100A9 strongly activates TLR4, a proinflammatory receptor, and thus activates pathological inflammation. Understanding how S100A9 interacts with TLR4 would be useful to create therapeutics to treat these diseases. My project is to use evolutionary and biochemical techniques to find out what sequence changes to S100A9 were important in its evolutionary history that led to greater proinflammatory activity. I will continue to characterize modern mammalian S100A9s that diverged more distantly from humans such as koala, platypus, and echidna, using recombinant protein expression and purification of S100A9 proteins from Escherichia coli followed by functional assays in human embryonic kidney cells. I will also couple these studies with further characterization of how TLR4 specificity and activity for endotoxin, the pathogenic ligand for which TLR4 evolved to recognize, changed in different species. These data will help us understand how the host protein S100A9 evolved inflammatory activity, and how TLR4 evolved to activate with a variety of ligands.

Wearable Microfluidic Colorimetric Sweat Sensors for Real-Time Personalized Hydration Monitoring

Presenter: Albert Yim – Neuroscience

Faculty Mentor(s): Jonathan Reeder

Session: (In-Person) Poster Presentation

Continuous, real-time sweat analysis is an underdeveloped field with promising applications ranging from aiding clinical health care to tracking athletic performance. Noninvasive, biochemical metrics indicative of physical exertion, hydration, and injury risk are highly sought-after. Currently, microfluidic devices allow for noninvasive collection and storage of sweat through precisely engineered microchannels but lack a method to record continuous sweat rates. Sweat rate and biomarker composition are highly variant between individuals, requiring a personalized hydration feedback approach. The biomarker variance is significantly attributed to sweat rate, making rate normalized biomarker concentrations from recorded continuous sweat rates indicative of performance metrics. Photolithography was used to create molds with designed microchannels. SIS was used to create a soft, flexible device to collect, store, and analyze sweat. UVO treatment increased efficiency of device bonding and fabrication. Colorimetric reagents were used as the basis for a gradient system to characterize a continuous sweat rate. This was analyzed using video documentation and a pressure-driven flow pump at set flow rates to emulate sweating. Data obtained was suggestive this system was able to measure a continuous sweat rate but was not conclusive. Further research as the sources of inconsistency in results would be required before this would become a feasible method to measure biomarker changes.

Expression of FGF Signaling Genes during Threespine Stickleback Development

Presenter: Micah Woods – Environmental Science

Co-Presenter(s): Vithika Goyal

Faculty Mentor(s): Hope Healey, William Cresko

Session: (In-Person) Poster Presentation

The fibroblast growth factor (fgf) signaling pathway is essential to vertebrate craniofacial development. Alterations in fgf receptors and ligands can lead to craniofacial disorders. While deleterious effects are observed in response to pathway mutations in many vertebrates, syngnathid fishes (pipefishes, seahorses, seadragons) have lost several of these genes (fgf3, fgf4, and others). Syngnathids have also evolved unique craniofacial features, such as an elongated snout, important to suction feeding, and absence of teeth. Since fgf3 and fgf4 are involved in craniofacial development, it is possible that their loss in syngnathids is related to the family’s unique faces. Our lab is investigating the developmental impact of the loss of fgf3 and 4 in syngnathids. To establish the ancestral expression patterns of fgf genes, we studied stickleback fishes due to their recent divergence from syngnathids. Using in situ hybridization, we assessed the spatial localization of fgf expression in stickleback embryos through development. Embryos were imaged and fgf/fgfrs staining patterns were compared to zebrafish. We observed expression of fgfr1a and fgf3 in the pharyngeal arches of stickleback embryos, paralleling zebrafish. Understanding the ancestral expression patterns of genes in the fgf signaling pathway reveals the deep conservation of the fgf signaling pathway in stickleback and provides opportunities for better interpreting the impact of the losses of these genes in syngnathids.

The relationship between prison work and education programs and employment post incarceration

Presenter: Max Wilson – Family and Human Services

Co-Presenter(s): Hannah Volker

Faculty Mentor(s): Miriam

Session: (In-Person) Poster Presentation

Study Purpose: Individuals who were formerly incarcerated have a more difficult time gaining employment than those who weren’t. Education programs offered in prisons are meant to help reintegrate individuals back into society once they are released. These programs include educational resources that cover basic education, GED certification, degree programs, trade training, and more. The purpose of this study is to examine the relationship between prison education or work programs and employment post incarceration.

Study Design: Using data from the Life Study, a dataset consisting of 411 individuals reentering their communities after incarceration, we conducted a Pearson’s Correlation to determine the correlation between any participation in prison education or work programs, and employment post incarceration.

Findings: Our findings suggest that there is no statistically significant correlation between participating in a prison education or work program and employment post incarceration.

Conclusion: These results may indicate that variables beyond education are involved in limiting the ability to find employment after serving one’s sentence. They could also indicate that the current way these programs are run is ineffective at preparing individuals for finding jobs. Future research should further examine this relationship and explore how to make prison education programs more effective at educating incarcerated individuals and preparing them for the workforce at reentry.

Methane Emissions in Hydropower Reservoirs

Presenter: Ashia Wilson – Environmental Studies

Faculty Mentor(s): Alai Reyes

Session: (Virtual) Poster Presentation

The Klamath Hydroelectric Project (FERC No.2082) does not track or manage their methane production and emissions related to their hydropower projects . Methane is a potent greenhouse gas resulting from the decomposition of organic material in environments with no oxygen; it has 80x the warming power compared to carbon dioxide during the first twenty years of being emitted into the atmosphere (contributes to climate change). PacifiCorp, owners, and operators of the Klamath Hydroelectric Project control 169-megawatt project located in a predominantly rural area in Southern Oregon. The project includes; Link River Dam, Keno Dam, J.C. Boyle Dam, Copco No. 1 Dam, Copco No. 2 Dam, and Iron Gate Dam. PacifiCorp states, “The project generates approximately 716 gigawatt- hours of emissions-free electricity on an annual basis – enough power to supply the energy needs of approximately 70,000 households.”

Dam construction has significantly altered water, nutrient, and ecosystem dynamics and fluxes in river networks and is linked to the amplification of methane emissions in deep-water hydropower reservoirs . From the very beginning of these projects, the emission of methane is present . The United Nations, many individual countries, and western states classify hydropower projects as “clean energy.” Under the United Nations’ Clean Development Mechanism, dams are one of the most common projects funded with carbon offset funds.

The Role of Ribosome-Associated Protein Quality Control in a Prion-Based Epigenetic State

Presenter: Phaedra Whitty – Biochemistry

Faculty Mentor(s): David Garcia

Session: (In-Person) Poster Presentation

A prion that has been discovered in yeast, [BIG+], allows cells to adopt a ‘live fast, die young’ strategy, accelerating growth rate at the cost of a shortened lifespan. Prions are heritable, alternatively- structured proteins that are implicated in many mammalian neurodegenerative diseases. However, they can also act as a beneficial epigenetic mechanism by altering gene expression in cells. The [BIG+] prion is a form of Pus4, an RNA-modifying enzyme conserved throughout nature, and has been shown to affect protein synthesis. The epigenetic state induced by it is characterized by accelerated cell proliferation, increased cell size, shortened lifespan, and increased translation activity. The mechanism of the [BIG+] prion remains unknown. This project investigates the ribosome-associated protein quality control pathway (RQC), a cellular system to monitor issues in translation, as a potential contributor to the [BIG+] phenotype. A genetic approach was taken to knock out each of four genes coding for proteins involved in RQC. These strains were used in luciferase reporter assays to examine the difference in translation phenotypes between mutant naïve and mutant [BIG+] strains. A notable change in the [BIG+] translation phenotype of mutants as compared to wild-type strains suggested the involvement of at least two RQC proteins, Hbs1 and Rli1, in the prion phenotype. These results are some of the first mechanistic insights into how this prion affects translation.

Exploring the Effect of Social Media Popularity Metrics on Curiosity

Presenter: Erica Waldron – Psychology, Sociology

Faculty Mentor(s): Dare Baldwin

Session: (In-Person) Poster Presentation

Social media inundates us with information about popularity; for example, social media posts are accompanied by a number of likes and comments. Dubey and colleagues (2020) recently demonstrated that such indicators of popularity influence people’s curiosity to learn more about specific topics. If so, this is one unexpected, beneficial side effect of social media popularity metrics. However, the way in which they manipulated popularity via Reddit-like “upvotes” may have introduced a confound into their findings. In particular, people were asked to report about an item’s popularity immediately before reporting on their curiosity regarding that item. The immediate juxtaposition of these two questions may have led participants to assume that popularity was relevant to curiosity, thereby creating what is called a demand characteristic that contaminated their findings. My thesis research attempts to replicate Dubey and colleagues’ research while avoiding this potential demand characteristic. People rated curiosity first and were asked about popularity only at the end of the survey. Analyses on preliminary findings modeled after Dubey et al. suggest that their findings are not replicating. That is, people are no more curious about items with a high number of upvotes than those with a low number of upvotes. To the extent that my full data set is consistent with this non-replication, these new findings bring into question whether popularity has any relationship to curiosity.

Geometric and Thermal Constraints on the Timing of Alaskan Tidewater Glacier Retreat

Presenter: Lucy Waghorn – Earth Sciences

Faculty Mentor(s): Dave Sutherland, Alex Hager

Session: (In-Person) Poster Presentation

Glaciers around the world are retreating at increasing rates, prompting concerns over sea level rise and the future of the cryosphere. In southern Alaska, some have retreated while their neighbors have advanced, indicating that local atmospheric conditions are not the only influence on glacial retreat. One possible factor is the interaction of ocean water with the glacier at the terminus. However, fjord geometry can alter the ocean water that interacts with the terminus, and the interaction of fjord geometry and ocean temperature anomalies has not been investigated in Alaska thus far. To investigate the interaction of fjord geometry and glacier retreat, we used bathymetry, air temperature (AT), sea surface temperature (SST), and terminus position data. Here we show that high SST anomalies may enhance glacial retreat in fjords with shallow sills. During a high SST anomaly, some glaciers in shallow-silled fjords retreated rapidly from a point of relative stability. Many glaciers also showed enhanced retreat in the two years after a high AT anomaly. It is possible that shallow sills influence fjord water circulation where only the warmest part of the water column can enter the near terminus region, potentially leading to enhanced glacier retreat after high SST anomalies. Though other factors can also contribute, understanding these processes and interactions that lead to glacier retreat is becoming increasingly important as climate change alters the atmosphere and environment.

Utilizing real time strain to modulate patient-specific rehabilitation optimizing bone recovery

Presenter: Alyssa Vongphachanh – Human Physiology

Co-Presenter(s): Walker Rosenthal

Faculty Mentor(s): Kylie Nash

Session: (In-Person) Poster Presentation

Severe bone injuries often result in high complication rates and poor functional recovery. Mechanical loading through rehabilitation is a longstanding treatment for these injuries, but current practices are still challenged with variable healing, limiting this promising therapeutic [1,2]. Recent advancements in implantable strain sensors may promote better understanding of how rehabilitation induced loads contribute to healing outcomes [1]. Our lab uses this idea in a rat femoral segmental model stabilized with an internal fixation plate embedded with an implantable strain sensor to analyze the mechanical environment throughout healing for different loading conditions. Past work has found that load-sharing (compliant) fixation devices exhibited improved healing outcomes when compared to load-shielding (non-compliant) fixation plates [3]. We investigated the effects of rehabilitation on bone volume by using a wireless compliant fixation device capable of acquiring real-time micro-strain measurements on a segmental defect in the femur. We found that bone union occurred in 3/3 rehabilitated rats and only 2/4 in non-rehabilitated, sedentary counterparts. Rehabilitated rats experienced a higher mean strain amplitude and their bones bridged earlier than their sedentary counterparts. Our findings suggest a relationship between strain and bone healing outcomes. We hope to further explore the effects of rehabilitation intensity on local defect strain and thus bone healing outcomes.