2022 Whitman Undergraduate Conference Poster Presentations

This poster was only available for viewing at the in-person event.

The hormone auxin plays an important role during the processes of growth and development in plants. In corn, one essential part it plays is to facilitate the proper development of the plant's reproductive parts: ears and tassels. Two main protein types, repressors and receptors, are used by a plant cell to detect auxin and respond to its presence. By experimentally mutating and cutting off regions of repressor proteins, we identified important regions of the protein sequences that control the speed of repressor degradation when auxin is introduced to the system, and we were able to show that these same regions are found across different plant species. Our findings could assist genetic engineers seeking to fine-tune crop development.

Faculty Sponsor: Brit Moss
Research Funding Source: National Science Foundation

The body’s ability to sense and regulate nutrient states is essential for maintaining energy homeostasis. Disruptions to this process can cause disorders in bioenergetic balance, including obesity and anorexia. Unpaired2 (Upd2) — the Drosophila ortholog of the human fat hormone leptin — modulates energy intake by signaling satiety during nutrient-rich conditions. Phosphatidylethanolamine (PE), the second-most abundant membrane lipid in eukaryotic cells, has recently been shown to modulate Upd2 release via conjugation with Atg8, an autophagic protein involved in the turnover of membrane-bound organelles. Using fat body-specific gene modulation, our work explored the impact of diet and PE biosynthesis on feeding behavior and starvation response in Drosophila flies.

Faculty Sponsor: Jim Russo
Research Funding Sources: Fred Hutchinson Cancer Research Center, National Institutes of Health

This poster was only available for viewing at the in-person event.

In spring of 2021, only 1.2% of surveyed American college students reported experiencing no stress. Due to the prevalence of stress and its demonstrated negative impact on memory retrieval, we aim to explore how stress affects the process of learning. Zebra finches are an appropriate model for our research because they utilize similar processes as humans do, during vocal learning. In this project, we test the effects of corticosterone (a stress-related hormone) on song learning in adult birds, adapting a protocol by Tumer and Brainard (2007) that involves shifting the pitch of birds’ songs via negative reinforcement in the form of white noise. We predict that birds receiving corticosterone manipulation will have impaired learning. Such an effect would imply a moral imperative on colleges to prioritize the reduction of students’ stress levels and/or find methods of buffering the effect due to its inhibition on students’ ability to learn.

Faculty Sponsor: Nancy Day

Our research was centered around modeling the patterns of vibrations that occur on a guitar top plate at different stages of assembly. We used a computational technique, finite element method, to model the frequencies and shapes of standing wave vibrations of a guitar top plate. Proper modeling required measuring the shape of the top plate, tone hole, and bracing pieces, and their grain orientation. In addition, the calculations required obtaining the stiffness matrix of the wood. The model identified both the shape of the standing wave vibrations and their frequency. These results were compared to experimental measurements of the frequency and vibrational shapes of several  guitar top plates during each step of assembly. Good agreement between the model and the measured data was obtained at the lowest frequencies, but as the frequency increased and the vibration patterns became more complex, the model results no longer matched well with experimental data.

Faculty Sponsor: Kurt Hoffman
Research Funding Source: Department of Physics

This poster was only available for viewing at the in-person event.

Extreme oxidative stress alters basic cellular function and causes DNA mutations that lead to increased risk for cancers, inflammatory diseases, and other illnesses. Dietary sulfur-containing amino acids have been identified as a starting point in biochemical pathways that protect against oxidative damage. For my study I used genetically modified mice, lacking NADPH-dependent disulfide reductases that normally prevent oxidative stress, as a model system. I found that the mice were able to survive without these enzymes, indicating an alternative mechanism for combating oxidative stress: specifically, via the catabolism of methionine. I synthesized and purified stable, heavy-isotope, sulfur-labeled versions of two sulfur-containing amino acids, methionine and cysteine. I used these labeled isotopes and mass spectrometry to track and compare the metabolism of sulfur through the livers of both genetically modified and wildtype mice. A better understanding of this biochemical pathway will suggest therapeutic targets for improving cell robustness under oxidative stress.

Faculty Sponsor: Dan Vernon
Research Funding Source: Whitman Internship Grant

This poster was only available for viewing at the in-person event.

Drug-resistant pathogens are one of the most challenging issues in public health. Many species of bacteria have developed strong resistance to several groups of antimicrobial agents due to the widespread utilization of antibiotics. Thus, searching for new sources of antimicrobial agents to address this problem is urgent. The human gut microbiome may represent a new alternative source of therapeutic drugs for the next era as it contains trillions of microorganisms that have co-evolved with the human host, some of which have probiotic effects. In this study, we used probiotic capsules as a model system of the gut microbiome to test the hypothesis that microbes found in the gut could inhibit the drug-resistant Pseudomonas aeruginosa. Some isolated bacterial species from the capsules showed small zones of inhibition, suggesting potentially modest antimicrobial activity. Further studies of the gut microbiome could yield new clinical treatments against chronic and infectious diseases.

Faculty Sponsor: Ginger Withers
Research Funding Sources: Faculty-Student Summer Research Award, M.J. Murdock Charitable Trust

This poster was only available for viewing at the in-person event.

Auxin is a hormone known to affect development in maize ears and tassels by inducing repressor degradation, but the full picture of repressor and receptor interaction remains unclear. Transport Inhibitor Response 1 (TIR1) is the receptor protein that initiates repressor degradation in response to auxin. Previous studies identified several amino acid residues in Arabidopsis TIR1 that significantly affect repressor degradation. We made analogous mutations in maize TIR1 (ZmTIR1) and confirmed similar effects. Mutations disrupting sidechain chemical properties showed a drastic drop in degradation rate; mutations causing minor changes resulted in little to no effect. Since these mutations are distal to the binding site, they are likely affecting interactions with the disordered parts of repressors flanking the auxin-binding region, disrupting dimerization of ZmTIR1, or causing a larger structural change affecting repressor-receptor binding. The result furthers understanding of the signaling pathway at the molecular level, contributing to future improvements in corn production.

Faculty Sponsor: Brit Moss

This poster was only available for viewing at the in-person event.

Plants, like animals, are able to sense and respond to the presence of small-molecule hormones, such as auxin, that help the organism to grow and develop. When the hormones are not present, the organism arrests development to conserve its resources, using a tightly controlled regulatory system. When mutations are introduced into the proteins that normally detect these hormones and perform the corresponding regulatory functions, the organism's speed of growth and development may be significantly affected. In my study, I quantified the effects of this hormone at the molecular level, using a yeast model to express auxin-detection proteins with altered binding sites, and then studying their breakdown. I intend to assess the impacts of these altered proteins in growing corn crops, with the hope of discovering more about this elegant system.

Faculty Sponsor: Brit Moss
Research Funding Source: Arnold and Mabel Beckman Foundation

Alzheimer’s Disease (AD) is a neurodegenerative disease that impacts the lives of millions in the United States. AD is characterized by the formation of amyloid plaques in the brain that disrupt neuronal function. The accumulation of amyloid beta (Aβ), a byproduct of the breakdown of amyloid precursor protein, leads to the development of these plaques. Previous research has shown that peripheral organs such as the liver play an essential role in clearing circulating Aβ and preventing early-onset AD. We hypothesized that damage to the liver caused by alcohol would lead to an increase in circulatory Aβ and thus, possible early-onset progression of AD. From our experimental analysis involving two proteins that are involved in Aβ clearance, we found that alcohol damage decreases the liver’s ability to take up and hold Aβ, suggesting that alcohol-related liver damage and dysfunction may be a factor in the early development of AD.

Faculty Sponsor: Jim Russo
Research Funding Source: Whitman Internship Grant

Complex posttraumatic stress disorder (cPTSD) has several detrimental consequences and can be linked to adverse childhood experiences (ACEs). Toxic stress theory posits that exposure to persistent ACEs without the presence of a supportive caretaker chronically activates the stress-response system; this exposure causes cPTSD and leads to flashbacks of traumatic events, avoidance behaviors, and paranoia. The theoretical model I have developed explores the mechanism through which ACEs lead to the development of cPTSD, and whether the most effective cPTSD treatment would involve the use of psychedelic drugs. Psychedelic drugs work to reduce negative self-concept and dysregulated emotions, which are both characteristic of cPTSD. Treatments for cPTSD involving psychedelic drugs are potentially beneficial, but are unfortunately understudied in psychology labs due to their classification as a Schedule I substance. Thus, theoretical work is needed to explain the potential mechanisms involved in such treatment programs.

Faculty Sponsor: Erin Pahlke

Oncolytic virotherapy is an emerging cancer treatment strategy involving the use of viruses that have been genetically engineered to preferentially infect and kill tumor cells. An advantage of this treatment strategy, compared to conventional methods of chemotherapy and radiation, is that it offers a high level of precision for eliminating tumors while avoiding causing harm to bodily organs or prompting debilitating side effects. Mengovirus is a type of picornavirus that offers promise as an oncolytic virotherapy agent, but due to its propensity to negatively impact or even kill small mammals like mice, performing pre-clinical trials has been a challenge for researchers. In my project, a newly engineered strain of mengovirus (MC0-R) was evaluated for safety in different types of cell cultures, with the aim of determining whether it may successfully avoid toxicities in mice during pre-clinical trials. If successful, this mengovirus strain may become a new oncolytic virotherapy agent.

Faculty Sponsor: Jim Russo
Research Funding Source: Mayo Clinic

As the world has seen a push toward sustainable development, chemists have answered the call by creating more environmentally friendly laboratory processes. Biocatalysis is an example of an eco-friendly process because it enables the use of mild reaction conditions. Our present study focused on the dioxygenase biocatalysis system. Ralstonia eutropha B9 is a mutant soil bacterium that expresses an enzyme within the dioxygenase system called benzoate dioxygenase (BZDO). BZDO catalyzes the oxidation of benzoates to form important synthetic molecular building blocks. Given that many of the most desirable BZDO substrates are commercially unavailable, we attempted to access them via chemical synthesis. We used quantitative nuclear magnetic resonance (NMR) spectroscopy to evaluate the transformation of non-native substrates of BDZO, then described the preparation of these compounds and evaluated their suitability as substrates for BZDO. This work allowed us to examine the impact of substrate electronic and steric properties on enzymatic activity.

Faculty Sponsor: Jon Collins

Studying evolution of anthocyanin pigmentation may show how genetic changes influence phenotype. Previous studies on monkeyflowers show that the gene MYB5 is sufficient and necessary for solid petal lobe anthocyanin (PLA) pigmentation in Mimulus luteus var. variegatus. Two RNA sequence variants were discovered in M. l. variegatus MYB5 exon 4, possibly due to RNA editing. I cloned and sequenced MYB5 exon 4 to confirm this. Then, I investigated the parts responsible for PLA evolution in M. l. variegatus. I attached both variegatus and M. luteus var. luteus coding regions to the same promoter, predicting that the variegatus transgene would result in stronger expression of anthocyanin if the pigment gain was a result of alterations on both coding regions and cis-regulatory modules. I found that the coding sequence change in luteus resulted in more vivid anthocyanin, and therefore variegatus evolved PLA only by cis-regulatory changes, which affect gene expression.

Faculty Sponsor: Arielle Cooley
Research Funding Source: National Science Foundation

This poster was only available for viewing at the in-person event.

Antibiotics are naturally produced by many species of bacteria and fungi. However, decades of heavy clinical antibiotic use have led to the rise of multidrug-resistant bacteria ("superbugs") that continue to proliferate in the face of current-generation antibiotics. A better understanding of the bacteria that naturally reside in our gastrointestinal tract (GI, or gut) and the antibiotics they produce could pave the way for a new generation of antibiotics. Our research studied whether species of bacteria that commonly reside in the human gut microbiome are capable of producing antibiotics against common pathogenic strains of bacteria, specifically, Staphylococcus aureus. We found that at least one strain of bacteria native to the human gut is capable of producing an antibiotic compound that inhibited S. aureus. This bacterial model system could be a good approach for identifying other novel compounds with antibiotic potential that are produced by our gut microbes.

Faculty Sponsor: Ginger Withers
Research Funding Source: Department of Biology

Nickel can be deposited into the environment via trash incinerators, mining operations, and smokestacks in metal alloy factories, and can be toxic to living organisms at trace concentrations. To determine the bioavailability of the metal to plants and other organisms in the environment, the rate of nickel uptake into a binding gel can be calculated. This rate is directly impacted by the presence of binding ligands in a solution. In this study, an environmental chemistry technique referred to as diffusive gradients in thin films (DGT) was used to measure the impacts of nickel uptake in binding gels. Using DGT, the mass of nickel accumulated in the binding gels was compiled and then used to generate models with various concentrations of both nickel and NTA, a binding ligand, at multiple pH levels. As predicted, NTA inhibited nickel uptake into the gels with varying efficiencies across the pH levels examined.

Faculty Sponsor: Nate Boland
Research Funding Source: National Science Foundation

Economic theory predicts self-interested agents will seek to benefit from the provision of public goods without helping to fund their provision; this is known as the “free-riding” problem. In real life, however, we see that public goods are plentiful. In this study, we extend the public goods literature on the dimensions of punishment and leadership. We show that sustained contributions to a public good are possible when agents do not know for how long they will interact, and that a leader with the ability to punish its constituents can serve as a coordinating device. In a pilot experiment that directly implements the theory, we find that participants may still fall into a free-rider equilibrium even with strong incentives to contribute. We also examine participants' beliefs regarding the contributions of other players and find differences related to demographic variables.

Faculty Sponsor: Jason Ralston
Research Funding Source: Department of Economics

This poster was only available for viewing at the in-person event.

Little is published on the insect diversity in the Blue Mountains of southeastern Washington/northeastern Oregon. The purpose of this study was to document the insect fauna on two Whitman College properties in the Blue Mountains foothills: Johnston Wilderness Campus (JWC) and College Cabin (CC). Insects were collected every week from early June to mid-August 2021 using handheld nets, pitfall traps, and night lights; most insects were collected on flowers. A total of 2,500 specimens were collected, representing 15 insect orders. Based on specimen identification to at least family level, approximately 345 insect species were found at JWC and 93 at CC. The order that encompasses bees, wasps, and ants was most prevalent, representing 47% of all species found at JWC and 54% at CC. Future studies that expand to include observations in early spring and late summer/fall will provide a more complete understanding of the insect fauna in this region.

Faculty Sponsor: Heidi Dobson

The "road movie" is a film genre defined as a “fictional narrative governed by movement, usually via car/road. The road movie tends to display a certain metaphysical or existential bent, via themes of rebellion, escape, discovery, and transformation” (Oxford). For this project, I analyze the film Ya no estoy aquí by Fernando Frías and argue that the film contributes to the road movie genre by choosing to narrate movement through the utilization of cumbia music and dance. The addition of cumbia personalizes the singularity in the movie's representation of "journey'': the travels of the fleeing immigrant. The road movie often features mobility and change along with a return; similarly, Ya no estoy aquí, along with cumbia music, holds connotations of nostalgic longing, isolation from one's home, and a growing melancholy that are crucial when depicting the journey of an immigrant's escape.

Faculty Sponsor: Aaron Aguilar-Ramirez

In this desperate time of COVID-19, can we still safely do the things we love—like play music together? During the past academic year, efforts to maintain health in schools during music rehearsals and performances have included various safeguards, such as singing with masks and covering openings on musical instruments with cloth barriers, in order to limit the flow of exhaled droplets into the air. In this study, I assembled a Schlieren system to test the effects of these different adaptations, measuring the resulting modification of flow of air from assorted instruments, including the voice. I found that with increasing layers in masks and instrument coverings comes greater restriction of forward air movement. As new questions are raised about safety and exposure to breakthrough infections of COVID-19, studies such as this one are critical in ensuring that audience members and performers are not exposed to undue risk of infection.

Faculty Sponsor: Kurt Hoffman

(Alternate Title:  Is Thermolysin Salt Activation a Story of Ion Binding and Hinge Bending?)

Thermolysin is a thermostable zinc metalloprotease excreted by the bacteria Bacillus thermoproteolyticus that catalyzes the hydrolysis of peptide bonds containing hydrophobic amino acids. It is used in industry for the production of a number of useful chemicals including a precursor (ZDFM) of the artificial sweetener aspartame, and it is studied extensively as a model metalloprotease. Previous research has established that thermolysin activity is increased by high concentrations of certain salts, but no mechanism has been identified for this activation. Separately, it has been observed that thermolysin undergoes a hinge-bending conformation change, characterized by a rotation of its two domains between an open conformation and closed conformation. Here, we use molecular dynamics simulations to observe how thermolysin behaves over time in solutions with different ion types and concentrations, in order to determine whether there is a link between thermolysin hinge bending and salt activation.

Faculty Sponsor: Douglas Juers
Research Funding Source: Faculty-Student Summer Research Award

Breast density is a known contributor to breast cancer risk. Studies examining the factors that impact breast density — specifically, the role of diets — have inconsistent results and focus mainly on older women (aged 40+). For this pilot study, we examined whether a 12-week dietary intervention improved the Alternative Healthy Eating Index (AHEI) scores for women aged 18–30 and, in turn, if AHEI scores impacted breast density. We also investigated the consistency of dual-energy X-ray absorptiometry (DXA) scan measurements both between and within DXA scan scorers, as DXA is a possible alternative to current methods of measuring breast density. We found significant changes in AHEI scores and significant correlations both between and within DXA scorers. Therefore, the results indicate dietary intervention was successful in changing participants' eating habits, and DXA scores are valid and reproducible within and between readers, supporting its use for measuring breast density in younger populations.

Faculty Sponsor: Leena Knight
Research Funding Sources: Breast Cancer Research Foundation, Fred Hutchinson Cancer Research Center

This poster was only available for viewing at the in-person event.

The element boron is able to bond to itself to form polyhedral cluster molecules, which have a variety of practical applications based on what atoms or groups are attached to the cluster. Heavily cyanated boron clusters—those with a CN group (carbon and nitrogen) attached to them—have been calculated to be highly effective electrolytes in metal-ion batteries. Unfortunately, only one heavily cyanated boron cluster has ever been synthesized. I present a synthesis of the second heavily cyanated boron cluster, the carborane CsCB₁₁H₆(CN)₆. The synthesis was completed using the parent boron cluster (CB₁₁H₁₂-), crystal iodine, glacial acetic acid, copper cyanide, palladium acetate, N,N-dimethylformamide, and microwave irradiation. The product CsCB₁₁H₆(CN)₆ was verified by nuclear magnetic resonance (NMR) and liquid chromatography mass spectrometry (LC-MS). This work has applications in improving metal-ion batteries and reducing their environmental impact.

Faculty Sponsor: Mark Juhasz
Research Funding Source: National Science Foundation

Educators are focused on finding ways to keep students’ academic motivation high. Driven by past research that indicates a link between parental involvement and academic motivation, many efforts to boost student motivation have been focused on engaging parents in schools. While some of these efforts have been effective, in reality some families do not have the ability to maintain a high level of involvement in their children’s academics. Thus, the goal of this study was to explore if another factor, such as self-efficacy, serves to increase academic motivation even in children with under-involved parents. I examined this question by recruiting a sample group of adolescents and their parents to complete online surveys focused on family involvement, self-efficacy, and motivation. Study results revealed positive effects of self-efficacy on motivation, and no effect of family involvement. My findings will help inform meaningful interventions for increasing motivation in children with low parental participation.

Faculty Sponsor: Erin Pahlke

This study investigated cognitive flexibility in monolingual and bilingual college students. We distributed a Qualtrics survey through email to Whitman College and Walla Walla Community College students that contained a language questionnaire as well as a Simon Task and categorization task, which are both established measures of cognitive flexibility. The language questionnaire consisted of 19 questions regarding language ability and history. Our Simon Task consisted of 28 congruent and incongruent trials in which the difference in response times would generate a Simon Effect. The categorization task asked individuals to rank strong, moderate, and weak exemplars based on how well they fit into certain categories (clothing, transportation etc.). We predict that bilingual individuals will demonstrate higher cognitive flexibility than monolinguals on both tasks. This finding, in collaboration with past research, will have implications for the development of cognitive flexibility, as well as further knowledge about the advantages of bilingualism.

Faculty Sponsor: Wally Herbranson
Research Funding Source: Department of Psychology

Unlike magnesium, manganese is toxic to humans at relatively low levels when consumed in drinking water. Manganese is especially toxic for children and infants; long-term low-level exposure has been linked to lower IQ levels, speech and memory issues, and behavioral changes in children. In the groundwater of the Shenandoah Valley region of Virginia, manganese is mostly natural, but it is difficult to predict whether water from a particular well or spring contains unsafe levels of manganese. Through my research, I aim to better understand how certain factors, such as proximity to surface water and faults, aquifer material, and interactions with other chemical constituents, affect manganese concentrations in groundwater. Given that most residents of the area rely on wells and springs for domestic water, understanding the factors that put a water source at risk of contamination is a public health imperative.

Faculty Sponsors: Nick Bader, Frank Dunnivant and Kirsten Nicolaysen
Research Funding Source: Keck Geology Consortium

Autonomous Sensory Meridian Response (ASMR) is a sensory phenomenon in which people experience a physiological response to specific audio and visual stimuli. Our study aims to test whether ASMR affects the rate of false memory production using the Deese-Roediger-McDermott (DRM) paradigm. The DRM paradigm is a procedure that elicits and measures false memories by providing participants with a list of semantically related words followed by asking them whether a related but absent word appeared. We also tested whether verbal vs. non-verbal material within the audio stimuli changed false memory production rates. We predict that ASMR audio will decrease the rate of production of false memories. Meanwhile, we predict that participants who examine DRM word lists with verbal audio will produce more false memories compared to non-verbal audio conditions. Our study expands on previous false memory research to explore whether sounds affect false memories of words that have not been examined.

Faculty Sponsors: Matthew Prull and Wally Herbranson