Current Program Research

Srijanee Basu

Advisor: Monica Chander

Investigation of the Role of SoxR in protection against endogenously produced antibiotics in Streptomyces coelicolor

Antibiotics are compounds that inhibit or kill bacteria. Yet, many clinically important antibiotics and other drugs are produced by bacteria themselves; the most notable of these bacteria are members of the Streptomyces genus, the majority of which are soil-dwelling organisms.  Because Streptomyces are active makers of antibiotics, or more accurately bioactive secondary metabolites, they invariably have specialised resistance mechanisms to shield themselves from these endogenously produced chemicals. Nevertheless, the intrinsic or generalized resistance mechanisms have not been well defined in Streptomyces.

SoxR is a redox-sensing transcription factor that is well-conserved among a host of bacterial species including Streptomyces. In our model organism, Streptomyces coelicolor, SoxR regulates five genes whose expression is dependent on the production of the redox-active benzochromanequinone secondary metabolite actinorhodin (Act). These SoxR-regulated genes include a membrane transporter and four putative proteins that could be involved in electron transfer reactions.

The Chander lab is interested in investigating whether the SoxR regulon protects S. coelicolor from potential toxicity of the endogenously-produced Act.  Our experiments will utilize the analysis of DsoxR mutant, Dact mutant, and DactDsoxR mutant strains and this work will thus supplement current understanding of fundamental antibiotic resistance mechanisms in bacteria that can provide insight into the evolution of antibiotic-resistant human pathogens.

Emelyn Cook

Advisor: Hannah Shoenhard

Quantifying and testing autophagy in α and β mushroom body neurons within transgenic drosophila melanogaster

Neurons must obtain energy to complete the intensive process of memory consolidation. One way to generate energy in a cell is the catabolic process of autophagy. Sleep not only regulates autophagy, but also a purpose of sleep is memory consolidation. In Drosophila Melanogaster, there are two forms of memory consolidation- one sleep dependent, and one sleep independent. Previous data from this lab has demonstrated that the neurons within Drosophila Melanogaster that mediate sleep-independent memory consolidation strongly induce autophagy when energy supplies are low, raising the possibility that this energy is used for memory consolidation. Yet to what degree do drosophila rely on autophagy during sleep independent memory consolidation, and does this energy come from autophagy?

To answer this question, we will perform two experiments using transgenic Drosophila Melanogaster. In the first experiment, we will dissect the brains of memory trained flies. Active autophagosomes will be visualized and quantified using confocal microscopy. In the second experiment we will knock down atg5, a gene that is essential to autophagy, and subsequently test their sleep independent memory abilities to determine the effect of atg5 upon memory. Should Drosophila rely on autophagy during sleep independent memory consolidation, we will see a large number of autophagosomes within sleep independent memory trained flies. Additionally, a knockdown of atg5 will cause a lack of memory in trained flies. If autophagy is not responsible for the burst in neuronal energy needed to consolidate sleep independent memory, the flies will still be able to remember when atg5 is inactive and will have a low number of active autophagosomes post memory training.

Nethmi Dharmasena

Advisor: Gregory Davis

Hope Hsu

Advisor: Tamara Davis

Analysis of 5hmC levels in Primary vs. Secondary DMRs Associated with Imprinted Genes

Our lab studies imprinted genes. Usually, mammals have two copies, or alleles, of each gene, one from each parent, and both alleles have the possibility of being expressed. However, imprinted genes silence one parent's allele and express the other. This process is very important because incorrect gene expression can cause problems like cancers or developmental disorders. Cells can determine which copy is silenced vs. expressed because one of the alleles is tagged with a chemical modification called methylation. One allele is methylated while the other is not resulting in areas called differently methylated regions (DMRs). DMRs are categorized in two ways based on time of acquisition and other characteristics. Differential methylation of the primary DMRs is inherited from the parents at fertilization, while differential methylation of secondary DMRs is gained during embryogenesis. Primary DMRs have highly consistent and symmetrical methylation. In contrast, secondary DMRs have more variable and highly asymmetric methylation on the complementary DNA strands.

During DNA replication at both primary and secondary DMRs, the maintenance methyltransferase Dnmt1 copies the methylation pattern of the template strand, which should result in symmetrical methylation, thus the high levels of asymmetry or hemimethylation observed at secondary DMRs is unexpected. Throughout these experiments our goal is to determine why there is significantly more hemimethylation at secondary DMRs as opposed to primary DMRs. We hypothesize that this difference is due to the oxidation of the methyl groups specifically at secondary DMRs. The oxidation of methylcytosine to hydroxymethylcytosine could prevent methyltransferase Dnmt1 from recognizing it thus leading to a failure in methylation maintenance, leading to asymmetry. Or 5hmC could be further oxidized leading to Dnmt1 perceiving it as damage and replacing it with an unmethylated nucleotide. To test the hypothesis that secondary DMRs are enriched for 5hmC we will use glucosylation followed by methylation-sensitive restriction digestion and quantitative PCR to determine the amount of 5hmC at secondary DMRs as compared to primary DMRs in newborn and embryonic brain/head DNA. Our preliminary research has shown that primary DMRs have little to no 5hmC while some secondary DMRs have much higher levels of 5hmC, consistent with our hypothesis.

Camilla Martin

Advisor: Tamara Davis

Analysis of Hemimethylation at Non-Imprinted Genes in Dnmt1 Mutant Mice

Generally, mammals inherit two copies (alleles) of each gene, one paternally and one maternally, and both copies are typically expressed. Certain genes in mammals, called imprinted genes, are expressed dependent upon which parent the allele was inherited from. For imprinted genes, one of these alleles, either the mother’s or the father’s copy, is silenced through methylation (the addition of -CH₃ groups to the 5’ position of cytosine). Methylation is acquired and maintained by DNA methyltransferases (Dnmts). To maintain methylation patterns in the developing embryo, Dnmt1 binds to the hemimethylated DNA produced during replication (molecules methylated only on one strand), and methylates the complementary cytosine. Imprinting is especially important for fetal development, as improper imprinting in humans can lead to disorders such as Prader-Willi and Angelman syndromes. The T. Davis lab studies how DNA methylation and gene expression are aLected in mice with reduced Dnmt1 functionality.

Previous research has shown that the Dnmt1 mutation leads to reduced methylation and increased hemimethylation at some of the regulatory elements associated with imprinted genes, but not at primary diLerentially methylated regions, which function as imprinting control regions. My research compares hemimethylation at non-imprinted genes in Dmnt1 mutant and wild-type mice. To ascertain methylation levels, I will be using bisulfite mutagenesis, a process which converts all unmethylated cytosine bases to uracil. I will be using hairpin linkers to connect the complementary strands of DNA, which will allow me to determine hemimethylation patterns. I hypothesize that the reduced methylation seen in Dnmt1 mutants is the result of increased levels of hemimethlyation, and I will find greater levels of hemimethylation in the Dnmt1 mutant mice. Additionally, I predict increased hemimethlyation will be restricted top genes previously found to be impacted by loss of Dnmt1.

Bronwyn McVeigh

Advisor: Thomas Mozdzer

Heritable trait variation in stomatal conductance and chlorophyll fluorescence in Phragmites australis

Coastal wetlands are important ecosystems due to the ecosystem services they provide, including carbon sequestration and coastal protection. Though global changes in CO₂ and nutrient enrichment continue to progress, their effects on these ecosystem services are largely unknown. The common reed, Phragmites australis, is a newly proposed model organism to study plant invasion and physiological responses to global change in coastal wetlands. Previous research in our lab has shown that Phragmites exhibits rapid evolution to global change with reductions in intraspecific genetic diversity and genotype level trade-offs to elevated CO₂ and N, but the contribution to heritable trait variation remains unknown. Two physiological traits, stomatal conductance and chlorophyll fluorescence, have been previously shown to vary at the genotype level, but it is unclear if these traits are heritable. To evaluate the heritability of plant traits, I will measure these two traits in an established a common garden of pedigreed parental and F1 Phragmites australis genotypes at Bryn Mawr College using a LiCor Li-600 porometer/fluorometer and an OptiSciences chlorophyll meter. I hypothesize that both traits will exhibit heritable trait variation, and this research is part of the C-EVO project which aims to determine whether evolutionary changes in response to global change can impact C cycling.

Mistica Mendoza Perez

Advisor: Seba De Bona

A field experiment examining the defensive coloration of spotted lanternflies and their signaling

Evolution has played a crucial role in developing anti-predator defenses that can act together or independently at various stages of the predation sequence. These traits and behaviors form a defense portfolio that an organism uses to reduce the rate of predation, increasing its chances of survival. In the case of invasive species, understanding this defense portfolio can shed light on its ability to escape from native predators.

The spotted lanternfly (Lycorma delicatula) is an invasive pest species in the United States with a broad defensive portfolio; its cryptic forewings, chemical defenses, deimatic behavior (startle displays), death feigning, and quick escapes have evolved to evade predation in its native habitat. Populations of this species have shown a rapid increase followed by a steep decline in PA, a common phenomenon in boom-and-bust dynamics.  For this project, we will investigate the role of the spotted lanternfly's cryptic coloration and deimatic behavior in evading predation in the States, enabling us to determine whether aspects of its defense strategy contribute to its spread.  Since deimatism exploits reflexive responses in predators, and does not require learning, it may provide an advantage over native predators with no experience. However, as the spotted lanternfly's deimatic behavior becomes less shocking to birds, we expect an increase in predation rates. Alternatively, the spotted lanternfly’s coloration might reflect aposematism (warning coloration paired with unpalatability). This hypothesis is supported by the fact that lanternflies can store secondary metabolites from their diet. Contrary to deimatism, aposematism is expected to increase with the experience of native predators, resulting in a decrease in predation rates as the species learns. Overall, our results can increase the potential to determine whether native communities can learn from experience to attack invasive species that rely on deimatic displays or aposematism.

Our experiments will involve both natural and altered static paper and clay models of the spotted lanternfly, which will feature variations in color and shape. Comparing the rate of attack on the different models by wild birds will inform us of the importance of detectability, familiarity, and aposematism. We will conduct experiments on the Bryn Mawr and Haverford campuses, surveying bird communities and tree species within our experimental sites. Additionally, we will deploy trail cameras to document the bird attacks and observe the behavior displayed during the attacks. Using the collected data, we will perform survival analysis and binomial generalized linear mixed models to quantify the effect of prey traits on predation rates.

With the given results, I will research whether aposematism of the spotted lanternfly is a crucial contributor to deterring native predators. Such results will highlight whether the aposematism of the spotted lanternfly is more critical in reducing predation, as the native community, through familiarity, learns that the spotted lanternfly's patterns of red as a sign of unpalatability is more impactful than the startle display through their deimatic behavior. Follow-up, longer-term studies could illuminate the importance of birds’ experience by spanning over their reproductive cycle to sample young, inexperienced birds. Furthermore, targeted studies could break down the specific sensory inputs that explain the efficacy of aposematic colorations and deimatic behaviors.

Asal Mogharehdehkordy

Advisor: Monica Chander

Exploring the Function of the Transcription Factor SoxR in Streptomyces coelicolor

SoxR is a redox-sensing transcription factor that is well-known for its role in protecting enteric bacteria, such as Escherichia coli, from global oxidative stress. In non-enteric bacteria, however, SoxR is believed to play a different role.  For instance, in Pseudomonas aeruginosa, SoxR is activated by phenazine antibiotics that the bacterium produces and regulates the expression of genes that facilitate the transport and modification of these redox-active molecules, to control their toxicity. Although SoxR is highly conserved among different bacterial species, its role remains poorly understood in the vast majority of bacteria.

Dr. Chander’s lab is interested in determining the function of SoxR in Streptomyces coelicolor, a soil-dwelling bacterium that produces several antibiotics, including actinorhodin (Act), a blue polyketide compound with redox activity. In S. coelicolor, SoxR activates the expression of five genes in stationary phase during the production of Act, and the Chander lab is interested in understanding the relationship between Act production and SoxR regulon expression.The lab hypothesizes that SoxR could protect the cell from toxicity caused by Act, which is a redox active biomolecule. Alternatively, SoxR could potentiate some beneficial effect of Act.

To investigate these models, we will study soxR and act S. coelicolor mutants strains, under different experimental conditions. Since SoxR is highly conserved in other Streptomyces as well, uncovering its function in S. coelicolor could reveal fundamental insights into bacterial regulatory networks that might apply broadly across different species. We will employ bioinformatics tools to predict SoxR regulons in other sequenced Streptomyces species. Ultimately, this research will facilitate a better understanding of the physiology of these medically important family of bacteria and could ultimately aid in the discovery of new bioactive compounds. 

Max Monks

Advisor: Thomas Mozdzer

Investigating genotype level variation in Phragmites australis seed germination under global change

Coastal wetlands are vital to the protection of our coastlines from anthropogenic change such as storms and erosion. The common reed, Phragmites australis, is considered to be a model organism for studying plant invasions and responses to global change in coastal wetlands. There is increasing evidence that global change factors can accelerate evolutionary processes, and research from our lab has demonstrated that Phragmites australis is experiencing rapid evolution in response to near-future CO₂ and nitrogen (N) enrichment conditions. Given its status as a model invasive organism, our lab has been investigating how reproductive output and seed germination of Phragmites australis vary as a function of genotype and exposure to elevated CO₂ (eCO₂) and N enrichment.

My goal is to determine if plant fecundity is driven by genotype (G), exposure to elevated CO₂ and N (E), or a combination of those factors. This summer I will build upon my work from Summer Science Research in 2024 in which I germinated over 400 seeds collected from Phragmites grown at the Smithsonian Global Research Wetland (Edgewater, MD) under elevated CO₂ and N conditions. Last summer I found significant differences in germination rate at the genotype level which may be a mechanism driving rapid evolutionary processes and may explain the ability of Phragmites australis to adapt to changing conditions. This summer I will increase statistical power by adding more replicates at the genotype level from panicles collected in 2024 that are currently being genotyped. Seed germination rate and death rates of seedlings at the G and E scale will be measured to determine if genotype and maternal treatment conditions affect the germination and growth rates of seedlings. I hypothesize that fecundity will vary at the genotype level, but that maternal plant treatment will have no effect on percent germination and early growth rates.

Kira Morozova

Advisor: Bárbara Bitarello

Evaluating equilibrium conditions of balancing selection models over varied timescales using forward simulation

Balancing selection (BLS) maintains adaptive polymorphisms in populations. It increases genetic diversity, ensuring that alleles do not go extinct. BLS can persist in a population on various timescales, and its different mechanisms - heterozygote advantage, negative frequency-dependent selection, antagonistic selection (including sexually antagonistic selection), and selection that changes across time or space in a panmictic population - exhibit distinct behaviors over time, allowing for a more definitive identification of the type of selection the population experiences.

The development of several methods for detecting BLS in the past two decades has shown that BLS has been more relevant in shaping genetic diversity in human populations than previously thought. Our focus will be on exploring BLS using SLiM, a flexible population genetic forward simulator, which allows us to model evolutionary scenarios with various parameters to evaluate the pre-existing methods of detection. These methods let us move on from a simply deterministic model, which cannot accurately represent heterozygote advantage among other factors, and add a stochastic component to the models. With new, stricter assumptions, the model becomes more realistic.

We will extend the models that have already been created by members of the lab and implement already existing packages into our work to widen the scope of relevant situations we can simulate. Other goals include working on efficiency improvement: SLiM has the capacity to interact with other simulators, which could run the neutral period of the simulation faster and allow the results to be exported for further modeling. Once a satisfactory model is achieved, we will be able to run thousands of simulations to confirm any preliminary results statistically. By integrating both computational simulations and theoretical analyses, we aim to gain a more comprehensive understanding of the effects of BLS on populations.

Mahnoor Nasir

Advisor: Adam Williamson

Investigating the Cell Biology of the Batten Disease Proteins

Batten Disease (also called Juvenile Neuronal Ceroid Lipofuscinosis, or JNCL) is a hereditary pediatric onset neurodegenerative disease impacting ~4 in 100,000 births worldwide. It is caused by mutations in one of 13 CLN genes, which lead to a suite of common symptoms that include neuronal loss, accumulation of autofluorescent material, sleep disruptions, seizures, and severe impacts on the visual system. At present, the cell biology of the 13 CLN proteins remains poorly understood. My project aims to explore these proteins and understand the mutations that can occur within them. I plan to reconstitute JNCL protein function in live cells to understand how the normal forms of these proteins help protect the nervous and visual systems. Additionally, by analyzing how this disease, which is classified as a lysosomal storage disorder, relates to phagocytosis, I hope to help pinpoint why debris buildup is a common outcome of mutations in otherwise distinct proteins. Through my work I hope to add to the existing knowledge about JNCL and contribute to ongoing efforts in the field to treat this disease.

Madeline Nobert

Advisor: Alison Weber

Insect flight requires rapid and precise sensory feedback in order to maintain balance and control. Understanding such precise information transmission is a valuable tool for exploring biological processing. It has been suggested that insect wings may also play a role in sensory feedback. The wings of insects contain special sensory receptors called campaniform sensilla, which detect strain on the surrounding cuticle as the wing deforms. The Weber Lab focuses on the hawkmoth Manduca sexta, a moth used often as a model organism due to its large size.

We aim to document how Manduca sexta responds to wing perturbation. We will monitor the activity of neurons using extracellular suction electrodes, and record how they respond to different stimuli that mimic in-flight obstacles. These perturbations will include gusts of wind and collisions aimed at different parts of the wing. We will observe activity at the wing nerve in conditions that mimic natural flight environments. By observing the processes by which these moths control their flight, we can gain insights into other complex movements like running.

Bianca Perez Ouhirra

Advisor: Hannah Shoenhard

Understanding the role of autophagy in memory consolidation and synaptic plasticity

Long-term memory consolidation is an energy intensive process, and it is hypothesized that a potential role of sleep is to relieve oxidative stress and replenish energy in neurons after long periods of consolidation. In Drosophila Melanogaster, long term memory either consolidates through a sleep dependent or sleep independent circuit, two independent pathways within the mushroom body region of the brain. While glia are a source of energy for neurons, we hypothesize that autophagy may play a large role in recycling cell resources and providing neuronal energy, as it is confirmed that starvation drives autophagy in both the sleep independent and dependent neurons. To determine whether or not autophagy is vital for memory consolidation, we will perform a necessity experiment by disrupting autophagy through knockdown of atg5 RNA post-developmentally in transgenic flies. This will be followed by a training period and appetitive memory assay to ascertain whether the performance index in the transgenic knockdown variant is significantly less than the control group. Should the transgenic variant perform worse in both sleep and wake conditions, this would suggest that autophagy is a vital energy resource for both variations of long-term memory consolidation.

Additionally, another hypothesized role of sleep is to reset synapses potentiated during wake to a baseline level. In conditions of sleep deprivation and aging, synaptic plasticity is seen to become dysregulated, over-strengthening synapses. We also aimed to discern through autophagy knockdown if brain-wide synaptic stability is dependent or supported in some form by autophagy, and evaluate how long autophagy must be knocked down in the mushroom bodies before seeing significant changes in the rest of the brain. To discern whether or not autophagy is vital for memory consolidation, we will perform necessity experiments by disrupting autophagy through atg5 RNA knockdown post-developmentally and observing changes in the synaptic marker bruchpilot (Brp). We will analyze and quantify synaptic changes using a confocal microscope to image Brp staining followed by quantifying the staining intensity using FIJI. These results are pertinent in contributing to the growing understanding of sleep and potentially contributing to research in memory and neurodegenerative diseases.

Carly Priest

Advisor: Hannah Shoenhard

Screening for Behavioral Phenotypes and Validating a Novel TBCK Mutant in Drosophila Melanogaster

TBCK syndrome is a rare but life-threatening neurodegenerative disorder caused by biallelic mutations in the TBC1-domain-containing-kinase gene (Durham et al., 2023). This mutation causes symptoms such as intellectual disabilities, hypotonia, seizures, brain atrophy, cranial deformities, and early death of the patient (Durham et al., 2023). First discovered in 2016, TBCK is severely underresearched, making it difficult to diagnose and develop treatments (TBCK syndrome, 2019). Using a Drosophila melanogaster model believed to contain a mutant allele of TBCK, TBCK^2F, developed by Dr. Hongjun Song’s laboratory at the University of Pennsylvania, this study aims to identify behavioral alterations in the TBCK^2F mutants and confirm their genetic identity to verify that we have a novel genetic mutant model for the human mutant allele TBCK. To determine behavioral alterations, we will assess sleep deficits using Drosophila Activity Monitors, hypotonia through geotaxis assays, impaired learning and memory using Y-mazes, and premature death by performing long-term survival assays. PCR genotyping will be used to genetically validate the presence of a loss-of-function mutation in the Drosophila mutants’ TBCK genomic sequence. If we confirm that both the genetic sequence and behavioral phenotypes match that of TBCK syndrome in humans, this validated model could then be used to screen for potential therapeutics. We plan to investigate a potential interaction with mTOR, a protein kinase regulating cell growth and proliferation that is found to be altered in humans with TBCK syndrome (Liu et al., 2013). If mTOR interaction is present, we will test the effects of drugs such as L-leucine or rapamycin that are known to affect this protein, and see if they ameliorate any harmful phenotypes displayed in the TBCK^2F mutants. This study aims to address the lack of research on TBCK syndrome by confirming a D. melanogaster model that will be used to investigate one possible mechanism of disease, mTOR interaction, that could point to potential therapeutics.

References

Durham, E. L., Angireddy, R., Black, A., Melendez-Perez, A., Smith, S., Gonzalez, E. M., Navarro, K. G., Díaz, A., Bhoj, E. J. K., & Katsura, K. A. (2023). TBCK syndrome: a rare multi-organ neurodegenerative disease. Trends in molecular medicine, 29(10), 783–785. https://doi.org/10.1016/j.molmed.2023.06.009

Liu, Y., Yan, X., & Zhou, T. (2013). TBCK influences cell proliferation, cell size and mTOR signaling pathway. PloS one, 8(8), e71349. https://doi.org/10.1371/journal.pone.0071349

TBCK syndrome. The TBCK Foundation. (2019). https://www.tbckfoundation.org/en/tbck-syndrome

Amelie Scalera

Advisor: Gregory Davis

Faizah Shaik

Advisor: Alison Weber

Behavioral analysis of responsive flight patterns during perturbations in Manduca Sexta

In order to maintain stable flight in a volatile environment, insects use rapid sensory feedback from mechanosensory neurons located in the halteres, antennae and wings. These neurons, called the campaniform sensilla, encode the environmental perturbations and form unique responses in order to maintain stability during flight. The Weber lab aims to study and understand this rapid and precise response in the hawkmoth, Manduca sexta on a behavioral and neuronal level.This summer, my goal is to further contribute to this understanding by characterizing the behavioral response of moths to perturbations (an example of which is wind gusts). I will record videos using a multiple high-speed camera setup to track the moths’ wing movement in response to the employed perturbation condition. The moth will be held in a stable position and destabilizing perturbations will be applied, including repeated wind gusts of different durations, pressure and frequencies which mimic environmental instability. The recorded videos would then be quantified to understand the coordinates of responsive wing movements with a software called DeepLabCut. This data, along with recorded neural responses via extracellular electrophysiology, will help us understand how sensory input is transformed into motor and behavioral output in response to external stimuli in moths. This research, along with advancing our knowledge of insect flight, will also further help in the development of technology that can benefit from rapid and precise responses to the environment.

Savannah Shaw

Advisor: Hannah Shoenhard

Energetic Cost and Source of Wake and Sleep Memory in Drosophila melanogaster

Forming a long-term memory in the fruit fly, Drosophila melanogaster costs energy and produces oxidative stress, while sleep replenishes energy and repairs oxidative damage. Flies have two different forms of memory; wake memory and sleep memory. We hypothesize that memories formed while flies are sleeping will be less energetically costly than those formed while they are awake. This will be investigated by performing a starvation survival experiment after sleep versus wake memory training. Flies will be starved for 18 hours and then memory trained using two scents in conjunction with a sucrose gel. After memory training, flies will undergo a survival assay to measure the cost of memory on their survival. Two groups of flies will be tested through this process; those who do not sleep after memory training and those who do sleep after the training. We will measure the survival curve of both groups to understand how sleep influences memory consolidation and its energetic costs.

Additionally, whether ketone supplementation improves memory in Drosophila melanogaster will also be assessed. In the absence of glucose, as in during starvation periods, ketones can be used instead of glucose to consolidate memory. This lab has found that supplying 2% ketones in starvation media boost fly survival under starvation conditions, but it does not boost memory consolidation. We will test whether a higher concentration of ketones can boost memory in flies. We will accomplish this by performing a survival curve and memory test on flies given different concentrations of ketones, with the goal of finding a concentration of ketones that optimizes fly survival. If we successfully identify an alternate concentration of ketones that boosts survival and memory, we will have have come to a better understanding of the energetic sources required for memory consolidation in flies.

Jo Smith

Advisor: Thomas Mozdzer

Heritable trait variation of herbivory among Phragmites australis genotypes from two populations

Salt marshes provide many vital ecosystem services, but their existence is threatened by accelerating global change factors, including rising sea levels, concentrations of CO2, nutrient pollution, and an increase in human infrastructure in these areas. The common reed, Phragmites australis, is a model organism for both invasive species and plant physiology.  Current research has demonstrated that exposure to both near future levels of CO2 and nutrient enrichment have reduced intraspecific levels of genetic diversity and altered plant traits suggesting that populations are rapidly evolving. Global change factors can also cause selective stressors for organisms, resulting in evolutionary responses shown in heritable trait variation responses like leaf toughness and herbivory behaviors. To evaluate the heritability of plant traits, 120 unique genotypes of P. australis were collected from two populations in MD, USA, the Smithsonian Global Research Wetland (Edgewater, MD) as well as Parker’s Creek (Prince Frederick, MD). A total of 240 genotypes were grown in a common garden at Bryn Mawr College in summer 2023. Common garden experiments allow researchers to evaluate heritable traits by removing confounding environmental factors. Common garden plants were then subjected to controlled crosses between the same population. Leaf toughness (lb/f) measures the force needed to puncture a leaf. This measurement simulates the sap sucking of aphids, the most common form of herbivory observed in Bryn Mawr’s common garden. Leaf toughness will be measured again this summer on the F1 generation of crosses from previous year’s genotypes. Data analysis comparing leaf toughness between individual genotypes and different populations will be calculated to determine if herbivory defense such as leaf toughness is a heritable trait response or an example of phenotypic plasticity in this species. 

Previous research shows plants exposed to elevated nitrogen have an increased relative growth rate as well as a higher number of aphids per plant. Major results show SERC plants have tougher leaves, suggesting greater resistance to herbivory. Findings also indicate that taller plants (according to max height of the growing season) are shown to have tougher leaves and therefore higher herbivory defense. These findings hypothesize that genotypes that were treated by nitrogen will have a higher growth rate and aphid density than plants that were not exposed to elevated nitrogen. This research aims to provide insights into which traits are heritable, to provide further insight to the evolutionary ecology of salt marshes as a whole. 

Tabia Tahsin

Advisor: Alison Weber

Electrophysiological mapping of wing sensor responses to perturbations in moths

Flying insects like Manduca sexta are very skilled at staying balanced mid-air, even when hit by a gust of wind or facing sudden disturbances. One of the major ways this is achieved is through the tiny sensory receptors on their wings called campaniform sensilla (CS). These mechanoreceptors detect when the wing bends, helping the insect make split-second adjustments. While many past behavioral studies support this idea, we are still not entirely aware of how these sensors behave at the neural level during real flight and also when the wing is suddenly disturbed. In this project, we are focusing on how those wing sensors respond when the moth is flying and encounters different types of perturbations, specifically wind gusts. In order to explore this we will be using a multisite probe (a very thin metal wire with multiple recording sites) and inserting it into the wing nerve. To figure out what kinds of wing movements trigger neural responses, we will move the wing to mimic natural flight and also introduce light wind gusts to simulate real-world perturbations. By doing this while recording from the wing nerve, we can start to see when and how often the neurons spike, and whether they respond at specific phases of each wingbeat. We are especially looking for how many times the neurons fire per wingbeat and whether certain neurons are tied to specific kinds of movements or reactions. We aim to understand how a small group of wing sensors can give the moth enough information to make fast, accurate adjustments mid-flight.

Raina Teter

Advisor: Adam Williamson

Functional Studies of the Batten Disease Genes

Batten disease is a family of 13 lethal neurodegenerative lysosomal storage diseases characterized by an array of symptoms including seizures, vision loss, cognitive decline, and movement disturbances. Batten disease is the most common pediatric onset neurodegenerative disease in the United States, and is worldwide the most commonly inherited pediatric neurodegenerative disease. Batten disease symptoms worsen over time, and ultimately lead to an early death for affected people. Batten disease is associated with mutations in 13 ceroid lipofuscinosis (CLN) genes. This summer, I will validate and continue to produce genetic knockout cell lines harboring mutations in each CLN gene to recapitulate this disease in vitro. When I have confirmed successful CLN gene inactivation, the knockout cell lines will be evaluated to determine the significance of these genes on key aspects of cell behavior that exhibit acute dysfunction in neurodegenerative diseases. In the long term, these cell-based assays could provide a new drug discovery platform to inform  approaches to therapy and treatment for this poorly understood and devastating disease.

Camille Veron

Advisor: Seba De Bona

Bluff or honest signaling: a field experiment to study the defensive coloration of spotted lanternflies

The spotted lanternfly, Lycorma delicatula, is an invasive planthopper that has rapidly colonized much of the Northeast United States over the past decade. In southeast PA, the lanternfly colonization has displayed a boom-bust dynamic, where rapid growth has been followed by a visible decrease in population size, a pattern common to invasive species. While the mechanisms by which this occurs are still underexplored, the predator-release hypothesis suggests that the absence of natural predators who have coevolved with the invader could favor a population boom. As native predators, initially naive to the invader’s appearance and behavior, gain more exposure and thus experience, predation pressure on the invasive species is expected to increase.

While relying on crypsis as a primary source of defense, spotted lanternflies possess a bright red pair of secondary wings, which are thought to have evolved as a form of antipredator defense. The efficacy of the coloration could be rooted in its sudden reveal, producing what is known as a deimatic display, a bluff that exploits hesitation by the predator. Alternatively, the wing coloration could represent aposematism, where a warning signal is paired with toxins or unpalatability. This study aims to examine the detection and signaling impacts of red coloration in lanternflies, within the context of the predator-release hypothesis. Clay and paper models of spotted lanternflies will be deployed, with four different colorations: (a) a natural, cryptic, closed-winged prey; (b)  an open-winged model, displaying the natural coloration of the hindwings; (c) an altered model with closed wings, but recolored to replicate the hindwing pattern; and (d) an altered model with opened wings, recolored to be entirely cryptic. The paper wings of the model will show differing shapes and coloration, while the clay records predator attacks. If deimatism is at play, it is expected that detection probability alone impacts attack rate, causing cryptic and/or closed-winged models to suffer fewer attacks. Alternatively, a marked decrease in attacks on brightly colored models, regardless of wing shape, would suggest aposematism plays a central role.

Because aposematism relies on predators learning to associate a warning signal with a consequence, predator experience will play a role in attack rates, with naive predators lacking exposure to the signal, and thus displaying higher attack rates. If the defense mechanism employed by the spotted lanternflies is deimatism, naive bird populations are hypothesized to have lower attack rates, being more susceptible to the shock caused by a deimatic display. Future studies could compare bird populations as the seasons progress, and new naive birds hatch, or spatially between areas that have and have not yet been colonized by spotted lanternflies.

Lia Wong-Fodor

Advisor: Tamara Davis

Analyzing DNA Methylation Patterns in WT and Dnmt1 Mutant Mice

One of the primary ways in which gene expression is regulated is via DNA methylation, a process in which methyl groups are covalently bound to CpG dinucleotides. Gene-specific methylation patterns are established in early embryogenesis via de novo methylation and are subsequently maintained, though they are not fixed and can be influenced by various environmental factors. The enzyme responsible for the maintenance of methylation is DNA methyltransferase 1 (Dnmt1), which adds methyl groups to the unmethylated strand of hemi-methylated DNA post-replication.

The T.Davis lab studies a mouse strain with a mutation in the intrinsically disordered domain of Dnmt1 with the goal of understanding the maintenance and stability of DNA methylation patterns, specifically at imprinted genes. While most genes are biallelically expressed in mammals, imprinted genes are monoallelically expressed in a parent-of-origin specific manner, meaning only the maternally- or paternally-inherited allele is expressed. The expression of the maternal vs. paternal allele of imprinted genes is regulated by DNA methylation at imprinting control regions. Dysregulation of these genes can result in developmental disorders, thus methylation maintenance at these loci is critical for normal development.

Over the summer, my research will focus on analyzing methylation at two genes: Zdbf2 and Gpr1. While most imprinted genes that have been studied are maternally methylated, these genes are part of the small group of imprinted genes that are paternally methylated, and thus merit further study. Using a bisulfite mutagenesis approach, I will analyze overall methylation levels as well as hemimethylation levels in both WT and Dnmt1 P/P mutant 18.5dpc mouse embryos. This will allow us to develop an understanding of the epigenetic regulation of Zdbf2 and Gpr1, as well as how the Dnmt1 mutation impacts the methylation levels and patterns of these paternally methylated genes.

Anna Gray Ashton

Advisor: Jonas Goldsmith

Synthesis and Assembly of Polymeric Transition Metal Complexes for use in the Production of Clean Hydrogen Fuel

Fossil fuel consumption has rapidly increased over the past century and, as a result, anthropogenic climate change threatens the health of our planet. It is imperative that we pursue alternative energy sources to eliminate the use of greenhouse gases. One promising alternative fuel is hydrogen gas which is storable and does not release harmful byproducts when combusted. One sustainable method for creating hydrogen fuel is photocatalytic water splitting (WS) which occurs naturally in photosynthesizing plants and can be mimicked with transition metal catalysts. The goal of this research is to develop a novel method for WS using a polymer composed of transition metal complexes (TMCs). This polymer will contain a photosensitizer (PS) complex and an electron relay (ER) complex. When the PS is excited by a light source, it can pass electrons to the ER, which then relays electrons to reduce the hydrogen atoms in water and generate hydrogen gas. The proposed energetic advantage of this process is that linking the metals together in a polymer film will allow for efficient electron transfer. Iridium and ruthenium TMCs are commonly used PS complexes due to their relatively long-lasting excited state and stability with rhodium commonly acting as their ER. This research aims to synthesize ruthenium, iridium, and rhodium polymers by linking the metals together with vinyl bipyridine ligands and to use potential-step chronoamperometry and photoinduced chronoamperometry to assess the light harvesting capabilities of the TMC polymer system.

Ellie Berry

Advisor: Bill Malachowski

A new synthetic route for cytisine 

Cytisine is a naturally occurring compound that is found in some species of plants. It has been proven to be effective as a smoking cessation drug, as it behaves as a partial agonist of nicotinic acetylcholine receptors, thus mimicking the effects of nicotine and reducing the cravings for nicotine stimulation. This summer in the Malachowski lab, we will investigate a new route to synthesize cytisine. The first step involves a double Mannich reaction with N-Boc-4-piperidone, which creates a second nitrogen-containing ring in the molecule. The ketone is then reduced with a Wolff-Kishner reduction. From here, we will be trying a range of photoredox reactions, and will run different analogs from these reactions to eventually create cytisine derivatives. This will likely involve new chemistry to create these derivatives. Any new cytisine derivatives that we may make will be tested for nicotine receptor bioactivity.

Sahana Datar

Advisor: Bill Malachowski

Synthesis of Cytisine and Related Heterocyclic Compounds to Advance Smoking and Vaping Cessation Therapies

Cytisine is a smoking cessation drug that acts as a partial agonist of the nicotinic acetylcholine receptors in the brain. We explored existing synthetic methods to make cytisine and combined these with alternative strategies. We designed a synthetic pathway to optimize the process starting with a double Mannich reaction followed by a Wolff-Kishner reduction and finally an organic photoredox catalysis step. We will explore different photocatalysts and reaction conditions to efficiently synthesize cytisine. Once cytisine has been successfully made, we hope to synthesize new analogs which may help advance smoking and vaping cessations therapies.

Virginia Durcan

Advisor: Ashlee Plummer-Medeiros

E. coli’s Paraquat Inducible (Pqi) Lipid Transport System

The double membrane of Gram-negative E. coli bacteria contains a protein system known as the paraquat inducible (Pqi) pathway. This protein system is comprised of an inner membrane protein (PqiA), a periplasmic protein (PqiB), and an outer membrane lipoprotein (PqiC), which function together as a channel to transport lipids between the inner and outer membrane of E. coli. Previous studies have examined the role of each protein in lipid transportation. However, interactions between proteins and their impact on lipid movement have yet to be tested in a systematic, controlled way. This research studies the function of the Pqi proteins by analyzing lipid trafficking; examining how each protein impacts the lipid transport rate and specificity will contribute to further understanding how and why lipid trafficking occurs in E. coli. Because lipid transport is essential for E. coli’s survival, knowing how this process ensues will contribute to developing more effective antibiotics that interrupt the lipid-transfer mechanisms and effectively kill E. coli bacteria.

The role of the Pqi proteins in this research will be examined through in vitro transfer assays, which will monitor the movement of fluorescently tagged lipids between donor and acceptor vesicles containing different combinations of the Pqi proteins. The proteins will be expressed in E. coli, purified through affinity chromatography, and analyzed by Size Exclusion Chromatography and SDS-PAGE.

From previous work, it is hypothesized that PqiC is needed to move lipids, but movement likely requires the presence of the additional Pqi proteins. Additionally, PqiA and PqiC likely play equally important roles in anchoring PqiB, and this work will investigate these specific roles. Future studies will analyze the effects of lipid movement in the presence of ATP and probe the transport rate of different types of lipids.

Carmen Gitchell

Advisor: Jonas Goldsmith

The Synthesis of Bimetallic Catalysts and Their Uses in Hydrogen Based Energy

The way that energy is created in the US usually produces carbon dioxide as a byproduct which is harmful to the atmosphere. Hydrogen energy can be made in a more green process though. The goal of the experiment in the future is renewable hydrogen-based energy as opposed to carbon-based energy. This project is focused on synthesizing a bimetallic molecule which works as a catalyst for the reduction of water using light energy, which produces hydrogen gas. One of the metal centers works as a photosynthesizer (absorbs energy and gets excited) which then transfers the electron to the electron relay. The electron is then transferred to an acid creating hydrogen gas. The transition metal complexes need to be close together for this to happen. One of the complexes will have an amine on it and the other will have a carboxylic acid. The two complexes are then connected through an amide bond. Previously this amide bond was formed using COMU as the coupling reagent; this work will focus more on a B(OCH₂CF₃)₃ as the coupling reagent as it has been shown to work well with more sterically hindered acids and bases. The work will involve synthesizing bipyridine molecules with amines and carboxylic acids to connect the transition metal complexes (which will be synthesized as well). In order to show proof of concept, both complexes will have ruthenium centers as the price of rhodium is quite high.

Jenna Mackenroth

Advisor: Ashlee Plummer-Medeiros

Computational investigations of lipid binding and movement in Escherichia Coli

Analyses of membrane maintenance and integrity have significant implications within targeted drug design and with particular respect to treatment-resistant bacteria. Research on mechanisms of maintenance, like intermembrane lipid transport, contributes to a deeper understanding of E. coli and other gram-negative bacteria’s mechanisms of survival. My research focuses on analyzing the role played by the inner membrane protein PqiA within Escherichia coli (E. coli) lipid trafficking. This work builds upon previous research implicating the PqiABC system within lipid movement between E. coli’s inner and outer membranes, grounded in past computational work performed on the membrane protein YebS by analyzing homologous/conserved residues in PqiA. Protein structures, generated by AlphaFold, and bilayer systems will be built using the modeling program CHARMM-GUI. Timed simulations of lipid-protein dynamics will then be run, allowing for visualization of interactions between PqiA and inner membrane lipids over a timeframe of ~500 nanoseconds. These visible interactions will be quantified based on bond distances, angles, and dynamics, while lipid behavior will be characterized through measurements such as order parameter, tilt, and interdigitation. While most of this research focuses on distinct molecular interactions, it is also more broadly concerned with the role PqiA plays as a member of the PqiABC transport complex. My research will work to argue that the interactions between lipids and this protein are enzymatic in nature, and that they contribute specifically to lipid shuttling between E. coli’s inner and outer membranes.

Sang Ngo

Advisor: Patrick Melvin

Novel Synthesis of Nitriles Using Sulfone Iminium Fluoride (SIF) Reagent

In medicinal chemistry and drug design, nitriles are significant due to their ability to enhance metabolic stability, which makes it an important scaffolding in drug design. The nitrile group’s small size and high polarity also allows it to have strong dipole interactions with proteins while fitting into tight binding pockets, as well as increasing its solubility and pharmacokinetics favorably. Nitriles can also mimic carbonyls or carboxylic acids, allowing a molecule’s electronic properties to be modified while maintaining the same conformation, which optimizes selectivity and potency. Sulfone iminium fluorides (SIF), a sulfur(VI) reagent designed in the Melvin Group, has traditionally been used in fluorination methodologies to produce high yields of fluorinated products with short reaction times (60s) at room temperature. Using this SIF reagent, I will study the possibility of the rearrangement of aldoxime substrates to synthesis aryl nitriles. We will also be looking into expanding the applications of these nitrile products.

Chi Nguyen

Advisor: Bill Malachowski

Synthesis of Nitrogen-Containing Bicyclic Structures with Quaternary Centers through Hydroxylamine Derivatives

Nitrogen-containing rings and quaternary centers are structures that are very commonly found in successful drug candidates. Thus, developing efficient, enantioselective methods to synthesize these structures is highly valuable. My research will be focusing on the synthesis of nitrogen-containing bicyclic structures bearing a quartenary center, potentially with enantioselelctive control. This will be achieved through the transformation of ethyl benzoate into a hydroxylamine derivative via the Birch reduction-alkylation reaction and S_N2 reactions, followed by the functionalization of the hydroxylamine oxygen and cyclization via a transition metal catalyzed hydroamination. This synthesis, if successful, will demonstrate how important drug-like moieties can be accessed by the methods developed in the Malachowski lab. This work could contribute valuable information for chemists working in drug development and synthetic organic chemistry.

Mina Rothberg

Advisor: Bill Malachowski

Enantioselective desymmetrizing hydroamination to synthesize complex all-carbon quaternary stereocenter containing saturated heterocyclic structures

Chiral carbons and tetrahedral carbons are useful in small molecule drugs because they provide more opportunities for intermolecular forces and interactions and promote better drug- protein affinity. Tetrahedral carbons also create more selective reactions with targets, which can aid in the reduction of side effects due to less interactions with other biomolecules. I will be working on a synthesis pathway involving a Birch reduction- alkylation followed by a desymmetrizing hydroamination cyclization reaction in order to generate . The initial compounds will be made using ethyl benzoate and a Birch reduction- alkylation will be conducted to create a symmetrical cyclohexadiene. The desymmeterizing hydroamination cyclization reaction, which will utilize a chiral copper or palladium catalyst, then generates a heterocyclic compound with a bridgehead quaternary carbon. The focus of my summer research project will be to test a range of conditions for this hydroamination cyclization reaction to find an efficient process and to then make the reaction enantioselective.

Keira Smith

Advisor: Jonas Goldsmith

Synthesis and Photoreductive Analysis of Electropolymerized Metal Complexes for Light Energy Harvesting

Current energy production methods rely on processes that emit harmful green house gases like carbon dioxide, contributing to environmental degradation and climate change. This research aims to develop a more sustainable and cost-effective method for hydrogen gas production through photocatalytic water electrolysis. The approach involves designing a bimetallic catalyst polymer to facilitate the reduction of water using light energy. This system consists of two key components - a photosensitizer (PS) that captures light and an electron relay (ER) that transfers the absorbed energy. To enable efficient light transfer, the goal is to create a polymer film consisting of alternating layers of the photosensitizer and electron relay. This will be done with ruthenium, iridium, and rhodium-centered complexes containing vinyl-bipyridines. The system will be powered by light energy, allowing the transfer of electrons from the photosensitizer to the electron relay. It will be tested with both cyclic voltammetry and potential-step and photoinduced chronoamperometry to test its effectiveness. This research has the potential to drive sustainable energy production while significantly reducing greenhouse gas emissions.

Sarah Walker

Advisor: Patrick Melvin

Exploring the Capabilities of Sulfone Iminium Fluoride Reagents in the Synthesis of Various Organic Products

Fluorine is an element that is of great commercial interest in the pharmaceutical industry, specifically due to its ability to change key properties of drug targets compounds, such as the stability, selectivity, and lipophilicity. However, transfer of a fluorine atom into organic molecules remains a difficult challenge. Our group utilizes a new class of sulfur(VI) reagent, called sulfone iminium fluorides (SIFs), to add fluorine atoms onto a chemical compound in as little as sixty seconds. This summer, my work aims to explore what compounds can act as a substrate for deoxyfluorination reactions using SIF in order to synthesize organic products. Along with deoxyfluorination reactions, we are also exploring the SIF reagent’s ability to facilitate interesting rearrangement chemistry.

Clara Fee

Advisor: Elizabeth Dinella

Test Oracle Generation for Real-World Bugs with Regression Oracle Editing

In software engineering and development, testing is widely used as an important stage to ensure correctness and proper behavior. Effective testing can find bugs, prevent regression to previous error states, and provide documentation. Unit testing is one type of testing in which the developer attempts to express a unit's intended functionality through a small test. Such tests consist of a test prefix, which calls or brings the unit under test into an interesting state, and a test oracle, usually expressed as a condition. The test oracle documents the intended behavior of the unit given the prefix.

However, writing these tests manually is time consuming and, ironically, may be a source of error. There is a need to reduce the effort of unit testing manually through an automated pipeline for unit test generation. Previous work has shown sucess in generating bug-finding prefixes. However, synthesizing a correct test oracle is a challenging problem as it must capture the intended behavior of the unit under test, not the current behavior. Some automated methods may succeed in generating interesting test prefixes but are only able to generate regression oracles that capture current behavior. Neural methods for automated test oracle generation show promise but often result in false positive and/or fail to catch real-world bugs. 

Our project proposes a new pipeline for stronger and more correct test oracle generation. We leverage previous work in test prefix generation to generate interesting prefixes for real-world bugs, along with regression oracles that only capture current behavior. Then, we use a pretrained neural editing model to transform the regression oracles into correct test oracles that will capture intended, not current, behavior.

In order to evaluate our project, we will investigate its bug-finding capabilities against a dataset of 854 real-world bugs in Java from various open-source projects, Defects4j. Our pipeline will provide better performance than state-of-the-art test oracle generation, EditAs2, measured by number of bugs caught from the dataset.

Our pipeline will help software developers and engineers to unit test their code, ensuring correctness and proper behavior. It will assist in the creation of safer, more stable, and more correct code in various fields of software development.

Ferida Mohammed

Advisor: Elizabeth Dinella

CRQBench: A Benchmark of Code Reasoning Questions

The prevalent use of Large Language Models (LLMs) for coding tasks necessitates robust evaluation metrics to analyze and improve their code reasoning ability. Existing benchmarks are often synthetic, relying on isolated functions that fail to reflect real-world programming. They also measure reasoning ability indirectly, making it difficult to attribute results specifically to LLMs’ code reasoning ability. CRQbench addresses these limitations by providing a real-world, contextualized benchmark for directly evaluating LLMs' code reasoning ability. This project builds on CRQbench by extending it to include contextualized code reasoning questions in Python and Java, offering a more comprehensive and multilingual evaluation. To achieve this, we will extract relevant data from the CodeReviewer dataset, which contains GitHub pull request comments, and replicate CRQbench’s LLM-assisted benchmark curation methodology. We will then evaluate different LLMs on the expanded benchmark and use these results to develop a system that employs program analysis tools to verify the correctness of LLM-generated answers to the CRQbench questions. This system will be further extended to explore fine-tuning LLMs to better utilize such tools and improve their responses. By addressing gaps in how code reasoning is currently evaluated, this project contributes to the development of more reliable, transparent, and effective AI tools for real-world software engineering. By the end of this project, we expect to have a multilingual, real-world, contextualized benchmark, a thorough analysis of LLMs’ code reasoning ability, and a practical framework for verification and improvement.

Lucy Brannon & Kaia Susman

Advisor: Don Barber

Exploring and expanding the methodology for the use of Environmental DNA in overwash deposits for past storm events

Environmental DNA (eDNA) is being investigated for its potential to be used as a proxy for identifying Nor’easters in sediment records. Currently, we are unable to distinguish between overwash deposits from hurricanes and Nor’easters in the sediment record through sedimentological analysis due to overlapping sediment characteristics. Our work aims to solve that by utilizing Environmental DNA (eDNA) to characterize microbial changes in the overwash deposits left behind by these powerful storms. Due to the unique seasonality of Nor’easters we hypothesize there will be distinct microbial communities in the North Atlantic Ocean during Nor’easter season (November – March) compared to during hurricane season (June – November) due to the inherent temporal differences. To explore the possibility of utilizing eDNA as a proxy for identifying Nor’easter overwash deposits, eDNA samples were collected after the occurrence of two Nor’easters from coastal New Jersey (NJ) salt marshes during the 2023-24 Nor’easter season. By sampling both before and immediately after storm events, we aim to capture the full spectrum of microbial community changes. Sediment cores containing known overwash deposits from a Nor’easter and Hurricane were collected from various sites across NJ coastal salt marshes in order to validate this technique. Over the course of the past year (2024-25) we have worked to extract eDNA samples and refine this technique. In summer 2025 we will continue to process samples from these well established overwash deposits as well as explore overwash deposits that are unknown to test the capabilities of eDNA as a proxy. This project aims to offer new insights into the history and frequency of Nor’easters. We hope our work will help fill that gap by establishing an accurate record of historical Nor’easters past the instrumental period.

Ellirene Fleming

Advisor: Pedro Marenco

Charlize Hoeun

Advisor: Don Barber

Analyzing the effects of salinity on carbon sequestration in North Carolina’s coastal salt marshes

Along the coast of North Carolina exists an abundance of estuarine salt marsh environments that harbor significant amounts of carbon within the sediment. The carbon in coastal wetland soils was removed from the atmosphere during photosynthesis of carbon dioxide by salt marsh plants (Spartina sp. and Juncus r.). As tidal marsh sediment accumulates over time, large stocks of organic carbon are sequestered below ground, and that carbon may remain buried for thousands of years. In this way, tidal wetlands function as carbon sinks while also providing other valuable ecosystem services; these services include buffering upland environments from storms and providing nursery habitat for organisms that are important marine seafood resources. Therefore, despite being threatened by sea-level rise, coastal development, and other land-use trade-offs, the maintenance of tidal wetlands is a resilience priority for coastal communities. However, the effectiveness of coastal wetland carbon sinks varies depending on estuarine environmental variables including salinity and tidal amplitude. The influence of these factors on marsh carbon stocks must be quantified to inform decisions about the preservation, restoration and enhancement of salt marshes in North Carolina.

My research this summer consists of mapping and assessing buried carbon stocks in estuarine salt marshes with a range of salinities and tidal amplitudes. My analyses will identify changes in carbon burial rates during the recent geological past (the last several hundred to 1,000 years). We will obtain new core samples from several North Carolina locations along a low- to high-salinity gradient. I will analyze and compare the bulk density, organic matter content, and carbon isotopic composition of the samples in Bryn Mawr’s sedimentology and geochemistry labs.

Based on preliminary studies that suggest higher carbon content in low-salinity and tidally restricted marshes, I hypothesize that environments with higher salinity and larger tidal amplitudes will be less effective as carbon sinks. The implications of my research, i.e., what kinds of salt marshes retain carbon better, will help address the pressing question of where and how best to protect tidal wetlands in coastal North Carolina.

Serena Liventals

Advisor: Pedro Marenco

Sonia Nicholson

Advisor: Don Barber

Assessing Saltwater Intrusion Through Storm Ditch and Groundwater Monitoring in Davis, NC

Saltwater incursion–the movement of saline water into ground and surface water–is intensified by sea level rise and is an issue in low-lying coastal communities. While saltwater incursion is a natural phenomenon, rising sea levels and physical anthropogenic influences, such as groundwater extraction and land-use changes, accelerate the process. Like many other coastal communities, Davis, North Carolina, is experiencing saltwater incursion alongside tidal inundation. In response to frequent flooding, local agencies have cleared and deepened storm drainage ditches in an attempt to mitigate water accumulation. However, it remains unclear whether this strategy effectively drains freshwater from the land or inadvertently allows marine tidal waters to flow further inland–particularly during high-water events–potentially exacerbating local saltwater incursion. While previous research has documented high water levels on roads in this area, the salinity of the drainage ditches and shallow groundwater has not been studied.

By installing a series of conductivity, temperature, and depth (CTD) sensors in drainage ditches and a groundwater monitoring well, this project aims to identify patterns of water movement and determine whether the ditches primarily drain freshwater or facilitate the inland intrusion of saltwater. Additionally, we plan to install two shallow groundwater monitoring wells to assess the relationship between groundwater levels and tidal fluctuations. By integrating data from the CTD sensors and groundwater well monitors, a high-resolution digital elevation model (DEM), precipitation and tide gauge records, and sedimentary particle size analysis, we hope to evaluate interactions between saline and fresh groundwater in this low-lying coastal community. The results of this study will provide insight into how water management strategies and climate change interact to influence the magnitude, extent, and duration of saltwater incursion. Furthermore, our findings will help inform potential community responses aimed at mitigating saltwater intrusion while also managing flooding events.

Sofia Prieto

Advisor: Katherine Marenco

Comparing Metazoan Contributions to Early-Middle Ordovician Reef and Non-Reef Sediment Textures Using Thin Section Point Counting

Reef ecosystems of the Early to Middle Ordovician Period (~485 to 460 million years ago) underwent a significant ecological transition. Reef structures once dominated by microbial frameworks shifted to include more complex metazoans. Understanding the distribution of metazoans within and around these reefs may clarify how they contributed to Ordovician marine ecosystems. As part of an ongoing study of Ordovician reefs in western Utah, my research will focus on thin section analysis of samples from the Ibex region. This project specifically compares the composition of samples collected from within fossil reef mounds to those from adjacent non-reef sediment and strata that overlie and underlie the reefs. By analyzing the distribution and abundance of metazoans, I aim to better understand how reef and surrounding environments differed during this transitional phase.

To analyze the composition of these reefs at the microscale, I will use a technique called point counting. This method quantifies the proportions of different components within a thin section sample by systematically recording the material present at a series of marked points. A grid will be superimposed over the thin section in order to identify components of the sediment texture. The thin sections I will be analyzing were prepared from samples collected in previous years from within fossil reef mounds and from adjacent non-reef areas. This approach allows for an accurate comparison between mound and non-mound settings, and complements existing spatial data collected in past years. The goal of this study is to assess how the composition of these reefs varies at a fine scale and to examine how metazoan contributions differ within and between reef mounds and surrounding sediment. These results will provide insight into ecological dynamics during the Ordovician reef transition and lay the groundwork for future comparisons with similar datasets from other regions.

Shuwen (Shera) Duan

Advisor: Olivia Chu

Matching Minds and Metrics: An Adaptive Approach to Stable Relationships

This paper explores an adaptive stable marriage model inspired by real-world relationship dynamics, where individuals evaluate partners based on personal preferences and weighted trait values—specifically appearance, wealth, and education. Each agent begins with randomly assigned preferences and weights, and iteratively adjusts them based on payoff satisfaction. To address the risk of infinite loops caused by extreme preference rigidity or mismatched priorities, we integrate the Roth-Vande Vate (RV) mechanism, a classical method that identifies and resolves blocking pairs in each round. By combining adaptive learning with RV’s deterministic improvement strategy, our model ensures convergence toward stable matchings while allowing for personal growth and evolving preferences. The results highlight how integrating structure into an otherwise flexible matching system can balance individual freedom with global stability—offering a more realistic and robust approach to modeling human pair formation.

Mei Gordon Washington

Advisor: Olivia Chu

Modelling population dynamics relating to the evolution of generalized reciprocity in female Norway rats (Rattus norvegicus)

Though rats are an often-disdained species, they are extremely sophisticated creatures. Female Norway rats (Rattus norvegicus), in particular, are highly cooperative and are known to live in structured colonies, demonstrate “affiliative behaviors” like allogrooming (grooming of an individual by a conspecific–a member of the same species), maintain social hierarchy, and engage in helping behaviors aligning with patterns of both direct and generalized reciprocity (Schweinfurth, et al. 2017).

Direct reciprocity is a cooperative mechanism where one individual, at some cost to themself, acts to benefit another with the expectation that the recipient will return the favor in a subsequent encounter. Hence, cooperation via direct reciprocity is inherently incentivized—“I help you, if you help me when we meet again.” In contrast, generalized reciprocity is not motivated by any such incentive and is not contingent upon the donor knowing anything about or having any relation to the recipient. In other words, generalized reciprocity is the evolutionary expression of generosity. Female Norway rats’ observed propensity for this behavior is hence a surprising result (Rutte & Taborsky 2007).

 Motivated by this intriguing behavior, our research will primarily model population dynamics of female Norway rats to attempt to answer the following questions: is there something about the social structure and hierarchy of Norway rat populations that is conducive to their evolution of generalized reciprocity? What social mechanisms are unique to female rat colonies that might explain why the same behavior has not been observed in males of the same species? Our work will make use of tools from evolutionary game theory (EGT)—a robust and rapidly expanding field of applied mathematics that adapts notions from classical game theory to study the evolution of populations. In EGT, instead of economic payoffs, biological fitness is considered, while rationality is replaced with natural selection, making it a useful framework for studying the evolution of traits and behaviors in animal populations over time. Our investigation will employ and build upon existing game-theoretic modelling and analytical techniques and be complemented by simulation studies.

The evolution of group interactions and the effects of conflict, cooperation, conformity, exploitation, and socio-cultural mechanics (e.g. behavioral reinforcement and punishment) on the adoption, rejection, and socio-spatial distributions of behavior and beliefs is a widely applicable area of study. In humans, for example, these evolutionary phenomena have been found to predict patterns of complex issues like collective interest networks, economics, and public policy, among many others.

Lily Hauck & Linnea Siderhurst

Advisor: Leslie Cheng

Fingerprint Data Compression Using Wavelets and Scalar Quantization

Since the establishment of its fingerprint archives, the Federal Bureau of Investigation of the United States has collected over 200 million sets of fingerprints. When scanned and digitized, each fingerprint image totals 1.5 inches by 1.6 inches. Each square inch requires 2 million bits of storage space. Considering that each bit is equivalent to one byte of memory, a single fingerprint card requires approximately 10 megabytes of memory to store. After limiting the database to 29 million sets, about 2x10¹⁴ bytes or 60,000 three-gigabyte computers are needed to store the system. There remains the process of transmitting this data to soliciting parties within a reasonable time frame. To remedy this problem, methods of data compression are used.

Wavelet-based compression is a powerful technique for efficiently encoding high-resolution images while preserving critical details. This research project will focus on applying the wavelet/scalar quantization method, developed in 1995 by a group at Los Alamos National Laboratory, to compress FBI fingerprint files, aiming to balance storage efficiency with forensic accuracy. The research will involve learning about different wavelet families and determining their suitability for preserving overall fingerprint characteristics. A key component of the study will be evaluating the pros and cons of different wavelet compression techniques to identify an optimal trade-off between compression ratio and biometric accuracy.

By implementing wavelet-based compression algorithms and comparing them against traditional methods, this project aims to assess performance and matching accuracy in fingerprint recognition systems. The results will contribute to optimizing fingerprint storage and transmission protocols for forensic and law enforcement applications.

Lucia Moscola

Advisor: Leslie Cheng

Predicting Stock Prices for American and Chinese Lithium-Ion Battery Firms

I will research stock prices for American and Chinese lithium-ion battery firms such as CATL, BYD, EnerSys, Enovix, and other major players. Lithium-ion batteries are efficient and long-lasting solutions for electricity storage, so their rise has corresponded closely with that of electric vehicles. Renewable energy sources, such as solar panels, also rely heavily on lithium-ion batteries to balance out uneven natural energy production.

Thus, understanding these stocks will give us valuable information about this increasingly important market sector, as well as clues toward the future of electric vehicles and renewable energy at large. I will utilize mathematical tools, including the Hull-White Algorithm for predictions in the Generalized Binomial Model and Geometric Brownian Motion in the Black-Scholes Model, to analyze historical stock data and create predictions of future stock movements.

China and the U.S. are the top two producers of lithium-ion batteries, although China is currently far ahead. Comparing battery companies based in the U.S. against those based in China will give us insights for the prospects of each country in our increasingly electricity-dependent world.

Lordina Oduro

Advisor: Leslie Cheng

Using Mathematical Pricing Modeling to Evaluate and Predict the Stock Performance of Zoom Video Communication Inc.

My research will focus on predicting the stock performance of Zoom Video Communications Inc., a company that became globally prominent during the COVID-19 pandemic. As video conferencing became a necessity for work, school and social interactions, Zoom’s stock increased. However, as life gradually returned to in-person norms, its stock experienced a sharp decline. This rise and fall make Zoom an interesting and relevant subject for analyzing stock price movements.

The second part of my research will examine option valuation on Zoom stock. Options are the right to sell or buy an asset and, in this case, a shared Zoom stock, for a predetermined price at predetermined date.

In this project, I will use real financial data and apply some of the math tools I learned in Introduction to Financial Mathematics course. To predict future stock prices, I will use the Hull-White Algorithm in the Multi-Period Binomial Model. In addition, I will use software tools such as R or Excel to help with simulations and data visualization, such as plotting stock paths and creating histograms. I am interested in how external factors, such as company earnings, industry competition, and broader economic indicators influence stock prices and investor behavior.

This research will allow me to bridge theory and practice by applying mathematical models to a real company with fluctuating stock prices. My goal is to gain a deeper understanding of how financial tools can be used to forecast market trends and support better decision making in investing.

Quynh-Chi Tran

Advisor: Leslie Cheng

The Mathematics of Merger Arbitrage as Event-Driven Investing Under Uncertainty

My research project investigates merger arbitrage as an event-driven investment strategy. Arbitrage is the practice of identifying and taking advantage of price discrepancies in financial markets to make risk-free profits. Meanwhile, merger arbitrage is an investment strategy striving to leverage from successfully completed mergers or takeovers. When an acquisition is announced, the target’s stock typically trades at a discount to the offer price, reflecting the market’s assessment of deal risk. This study aims to model and interpret that arbitrage spread as a function of deal structure, regulatory complexity, and broader domestic and global events.

My plan is to collect a sample of historical merger and acquisition (M&A) deals using public sources like Yahoo Finance and SEC EDGAR, track stock prices over the period between announcement and deal closure, and model the expected arbitrage return based on deal uncertainty. Some potential mathematical models that can be employed are expected value modeling, time discounting, stochastic processes, binomial models and basic regression techniques. Throughout this process, I will use software tools such as Excel, R-studio or Python to simulate returns and visualize price movements over the life of a deal. With reference to existing literature on merger arbitrage and the Wiley finance series, I want to expand further on how deal characteristics and external events, both domestic or global, influence spread behavior and deal timelines.

By comparing merger arbitrage opportunities across different geographies, sectors, and time periods, the project aims to highlight the interplay between financial modeling and real-world risk factors. This applied analysis contributes to a deeper understanding of event-driven investing and demonstrates how mathematical reasoning can inform portfolio strategy and capital allocation in uncertain market environments.

Kate Cheville & Alyssa Ya

Advisor: Michael Noel

Constructing a magneto-optical trap for ultracold Rydberg atoms

Our goal is to study highly excited ultracold atoms. To achieve this, we construct a magneto-optical trap to slow down and hold the Rubidium atoms. After the atoms have been trapped, we excite their valence electron to a higher energy level, turning them into Rydberg atoms. In this state, they exhibit exaggerated properties such as increased sensitivity to electric fields. This allows atoms to exchange energy over long distances through dipole-dipole interactions. The study of Rydberg atoms has important applications within quantum mechanics and quantum information science.

This summer, we will work on building another magneto-optical trap. To construct the trap, we will use a series of optical instruments and lasers to effectively slow down and hold the Rubidium atoms. We will also assemble the system of lasers and optics necessary to move the atoms into weakly bound Rydberg states.

Kaizhe (Kath) Cui & Ruimin Li

Advisor: Michael Schulz

Disorder in the One Dimensional Random Field Ising Model

The Ising model, originally developed to describe magnetic systems, has become a fundamental tool for studying complex behavior in disordered media. This project investigates the one-dimensional Random Field Ising Model, where each spin interacts with its neighbors and is also subjected to a local random magnetic field. Our focus is on the system’s entropy and energy as functions of the ratio r = 2J/h, where J denotes the interaction strength and h the field strength. Previous studies have identified a distinctive increase in entropy when r is an integer—referred to as the “on-spike” regime—contrasting with smoother behavior in the “off-spike” (non-integer r) case. Using tools from statistical mechanics and numerical methods, we reproduce known results in the off-spike regime by implementing a transfer matrix approach. We extend the analysis to estimate entropy in the on-spike regime and investigate how computational error scales with system size. These questions are not only mathematically rich but also deepen our understanding of how disorder influences physical systems. The insights gained may inform broader applications, including the design of materials and optimization in complex environments.

Marie-Claire Davenport

Advisor: David Schaffner

Investigating Turbulent Plasma Behavior

Plasma is a state of matter that governs nearly 99% of space. With the current state of research, it is impossible to have a model which perfectly encapsulates plasma. With its relevance in nearly all areas of STEM research, particularly to fusion energy, it is worthwhile to investigate plasma (to the best of our ability) to learn more about this state of matter. One notable behavior of plasma in the world of physics is turbulence.

The Bryn Mawr Experiment (BMX) is a chamber and vacuum system with a magnetized plasma gun source. The system has three sections: a copper section, where plasma plumes are shot out, an aluminum section for flux conservation, and a stainless-steel section for flux dissipation. Single-loop three-axis magnetic wire coils (b-dot probes) are used to measure fluctuating magnetic fields within the system. The BMX is a model used to study the behavior of plasma in space, specifically the interactions between the sun and the moon regarding plasma travel.

This research investigates the turbulent behavior of plasma by placing a semicircle-shaped ceramic Macor tile within the BMX plasma machine, like previous research projects. Contrary to the Macor ceramic tile used in previous research, the shape of the new tile should reduce the degrees of freedom of which plasma can behave and provide data on the fluctuating behavior of plasma.  

Anvita Deshpande, Bronwyn Hall & Ethan Furman

Advisor: Xuemei Cheng

Sputter Deposition of CoₓFe_1-x Films with Tunable Magnetic Damping via Composition Variation

Magnetic skyrmions, tiny and stable spin textures with topological protection, have recently been theoretically proposed as candidates for qubits in quantum information processing [1]. The estimated long coherence time (~ 10^-3 seconds) for the proposed skyrmion qubit is based on the assumption of ultra-low Gilbert damping of α=10^-5 and low temperature of T=100mK  [1]. However, achieving ultra-low damping in metallic ferromagnets is constrained by the scattering of magnons by conduction electrons. We plan to optimize a binary alloy of cobalt and iron to overcome this obstacle. This summer, we will apply the co-sputtering method to deposit Co_xFe_1-x films with Cu buffer and Ta capping layers on Silicon wafers. Deposition parameters like the sputtering gun tilt and sputtering voltage will be optimized to tune the Co concentration x, achieving low Gilbert damping. The structure and magnetic properties of these films will be characterized by X-ray diffraction and vibrating sample magnetometry.  Our results expect to further enhance our understanding of the mechanism for Gilbert damping, leading to the development of quantum materials for skyrmion qubits.

Rachel Friedman

Advisor: Asja Radja

Computational Model for Stimulus-Induced Motion of the Drosera capensis leaf

The carnivorous plant Drosera capensis captures prey on the surface of its leaves by catching it with sticky tentacles and subsequently folding over the prey creating an “outer stomach”. Both the phenomenology and mechanism underpinning this behavior are currently unknown. This summer, I will model the biophysical mechanisms underlying this folding behavior using computational models that I will develop in Python. Initial imaging experiments have shown that folding dynamics and final leaf conformation depend on food stimulus size and location on the leaf. Therefore, I will develop a numerical model that solves for the dynamics and final conformation of folding and will explore how our model parameters match experimental imaging. Our model will subsequently allow us to understand how the leaf’s proprioception, a known factor that affects plant motion generally, affects the motion of prey capture.

Marley Gerhart

Advisor: Michael Schulz

Gray Body Factors for Hawking Radiation from a Schwarzschild Black Hole

We will compute the gray body factors of a Schwarzschild black hole by analyzing the Klein-Gordon equation in the Schwarzchild spacetime. The Schwarzschild black hole is an electrically neutral, non-rotating, spherically symmetric black hole. The gray body factor of a black hole is the ratio of its (non thermal) Hawking radiation spectrum at large distance to the thermal black body spectrum emitted at its event horizon. Classically, nothing can escape from within a black hole’s event horizon. However, quantum mechanically, particles do escape via Hawking radiation. The transmission probability for this emission is determined by the Klein-Gordon equation, the relativistic counterpart of the Schrödinger equation. This transmission probability is the black hole gray body factor. We will show that the radial equation is a linear ordinary differential equation with four regular singular points known as the Heun equation. Computing the transmission probabilities is the same as matching the small and large radius limits of the solutions to the Heun equation. In these limits the radial equation simplifies to familiar equations of mathematical physics with fewer regular singular points (for example the hypergeometric equation) whose properties are well understood.

Maimoona Irfan

Advisor: David Schaffner

Plasma, an ionized state of matter governed by electric and magnetic fields, exhibits complex turbulent behavior that remains an active area of research in laboratory and astrophysical contexts. In the Bryn Mawr Experiment (BMX), turbulent plasma flows through a vacuum chamber, where various physical obstacles are placed in its path to simulate interactions akin to those between the solar wind and planetary magnetospheres. This setup enables the study of how magnetized plasma responds to localized magnetic perturbations and allows us to identify magnetic turbulence and wave fluctuations. My role centers on developing coding tools to analyze diagnostic data collected during these experiments. I will be working on coding signal processing techniques such as Fast Fourier Transforms (FFTs), band-pass filtering, and time series analysis to extract quantitative insights from the raw data. Additionally, I will contribute to PlasmaPy, an open-source Python library for plasma physics, by extending its magnetics analysis module through the addition of new functionality, comprehensive testing, and documentation, with the aim of supporting reproducible and accessible plasma data analysis.

Catie Kirk

Advisor: Asja Radja

Investigating the Flow Fields Surrounding Gorgonian Corals with Particle Image Velocimetry Analysis

Coral cover has dropped by 30-50% since the industrial revolution due primarily to warming oceans induced by climate change. While most coral species are declining in numbers, octocorals are an exception. These animals are in the same Class (Anthozoa) as threatened scleractinian corals, but they belong to a distinct evolutionary lineage with significant differences in morphology, skeletal structure, and biology. In the Caribbean, octocoral populations have increased since the 1980s while scleractinians have sharply declined. However, the mechanism underlying octocoral resilience is unknown. Understanding how these corals resist effects of climate change could provide insight into protecting coral species that are suffering population decline. We investigate how Gorgonians, a subclass of octocorals, influence flow fields surrounding them to effectively feed in the face of bleaching events or decline of food sources caused by climate change. We hypothesize that the geometric structure of a Gorgonian coral creates turbulent flow that promotes food capture. We use a flow tank built in-house to perform experiments simulating ocean flow fields. We image tracer particles surrounding the coral in the tank as a proxy for the water flow, and use a software tool from MatLab called PIVLab to quantitatively analyze the flow fields surrounding corals. By understanding the physical behavior that allows corals to feed, we will gain a deeper understanding of how they resist warming ocean conditions that otherwise harm other coral types.

Jordyn Strunk

Advisor: Michael Noel

Precision Mapping of the Stark Manifold

When Rubidium 85 atoms with a highly excited valence electron (n ≈ 33), called Rydberg atoms, are excited to a particular state in the middle of a harmonic ladder of energy levels, we see an increase in population of nearby energy states as the system evolves with time due to the dipole-dipole interactions with nearby Rydberg atoms. To make this harmonic ladder, we apply a static electric field to separate degenerate states into distinct energy levels that are nearly equally spaced, known as a Stark manifold. Our goal is to develop a technique to more precisely excite and resolve a desired state within the Stark manifold using microwave and laser pulses. This technique can be applied to the further and more precise collection of data regarding the interaction of Rydberg atoms that can aid in the development and research in the field of quantum information.

Annick van Blerkom

Advisor: Asja Radja

The plant Drosera Capensis is a carnivorous species that catches prey using their sticky tentacles, which contain digestive enzymes, located on the adaxial (upper) surface of its leaves. Over the course of several hours, these leaves fold or roll over the prey and entrap the prey creating an “outer stomach”. My goal this summer is to understand the phenomenology and underlying mechanism of this folding process. I will use time-lapse photography to identify the different folding movements and how these vary with prey location, size and spread. We will also use confocal microscopy to observe cellular changes as the leaf is folding, specifically measuring the sizes of cells before and after folding to understand how microscopic changes integrate to cause macroscopic folding motion. By combining macroscopic analysis and cellular observations, we hope to gain a comprehensive understanding of the folding behavior of Drosera capensis.

Tina Zhao

Advisor: Michael Noel

Measuring ultracold Rydberg atom density using 2-body and 3-body dipole-dipole interactions

Measuring Rydberg atom density is key to advancing research and can contribute to fields like quantum computing. We excite Rubidium-85 atoms to a Rydberg state where they can exchange energy through 2-body and 3-body dipole-dipole interactions. By looking at the time evolution and fitting our results to a simulation, we can determine the density of the cold Rydberg atom sample and compare to other methods to verify our technique.

Arshia Dolwani

Advisor: Cora Mukerji

The Role of Peer-Related Positive Childhood Experiences in Mitigating the Impact of Childhood Adversity on Self-Esteem in Adulthood 

Exposure to adverse childhood experiences (ACEs) is associated with a variety of negative impacts on health and psychological outcomes (Annett et al., 2023; Han et al., 2023; Narayan et al., 2018; Tan & Mao, 2023), including the development of self-esteem (Zhang et al., 2023; Yan et al., 2024). Recent studies suggest that pathways from childhood adversity to negative mental health outcomes in adulthood may be mediated in part through self-esteem (Kim et al., 2021; Sakyi et al., 2015; Wong et al., 2019). Emerging literature has begun to examine the impact of positive childhood experiences (PCEs) on adult outcomes, demonstrating preliminary evidence that PCEs are associated with better mental health outcomes and greater resilience, even among individuals who have experienced significant exposure to ACEs (Han et al., 2023; Scholtes & Cederbaum, 2024). However, much of the literature on PCEs is focused on experiences with parents or other caregivers; there is a significant gap in understanding how positive experiences with close friends may protect against the harmful effects of ACEs. Research has consistently shown that positive peer attachments have a strong association with self-esteem (Bishop & Inderbitzen, 1995; Harris & Orth, 2020; Wilkinson, 2004) and are also considered crucial for the development of self-worth (Sakyi et al., 2015). These relationships can be especially important for children experiencing ACEs in relation with parents or caregivers (Greenberg et al., 1983; Kim et al., 2021) and adolescents whose anchor for attachment shifts from parents toward peers (Wilkinson, 2004). In the present study, I will investigate how ACEs and PCEs involving peer relationships contribute to variation in self-esteem in adulthood. I will use data from an online study of a large, nationally representative United States sample. Participants retrospectively reported on their adverse (Philadelphia ACEs Survey; Cronholm et al., 2015) and positive childhood experiences (POS-DEV Retrospective Scales; Lopez et al., in prep) and completed self-report measures of their current self-esteem (Rosenberg Self-Esteem Scale; Rosenberg, 1965). I will test whether PCEs with close friends contribute independently to reducing the negative effects of ACEs on adult self-esteem or moderate the effects of ACEs on adult self-esteem. Additionally, I will explore how peer relationships at different stages of development (childhood versus adolescence) influence adult self-esteem. I hypothesize that PCEs with peers will have an independent protective effect on adult self-esteem: that is, higher levels of peer-related PCEs will be associated with greater self-esteem in adulthood, even after controlling for exposure to ACEs. This research aims to explore the potential protective role of peer relationships in the development of resilience. Given that self-esteem plays a critical role as mediator between childhood experiences and various mental health outcomes throughout life, the results of this study could provide insights into how social relationships can be leveraged to help support individuals who have experienced childhood adversity. 

Tanu Erdembileg

Advisor: Yeon Soon Shin

How does curiosity predict exploration and navigation performance?

Curiosity is an intrinsic drive for information (Kidd & Hayden, 2016) even in the absence of immediate rewards (Gottlieb & Oudeyer, 2018). Previous studies have shown that states of curiosity enhance memory for incidental information (i.e. minor details) encountered during states of higher rather than lower curiosity (Murphy et al., 2021; Cen et al., 2021), highlighting curiosity as a motivator of learning and enhancer of memory. Exploration is the process by which animals and humans gather information from novel surroundings, a form of spontaneous, uncoerced behavior (Renner, 1990). A recent study found higher pre-room curiosity states were associated with higher path roaming entropy (i.e. more spatial exploration) and found that individual differences in trait curiosity influenced the strength of this association, such as greater self-reported stress tolerance boosted curiosity-driven exploration (Cen et al., 2024). While previous work shows that curiosity correlates with greater exploration or path roaming entropy during navigation, it remains unclear how curiosity relates to the underlying decision-making process that guides exploration during navigation. Our research aims to investigate the relationship between curiosity and exploration through varying conditions (e.g. the weighting of entropy) and environments using a two-dimensional grid navigation and memory retrieval task. We aim to better understand how individual differences in curiosity across different types of environments can inform decision-making. We expect higher curiosity levels to predict increased deviation from reward-optimal paths and less structured, non-sequential memory retrieval patterns. This project may further explore how factors such as stress tolerance relate to variability in curiosity, spatial exploration, and navigation.

Ciara Grimes & Lisa Kim

Advisor: Anjali Thapar

ERP Correlates of Deception in Memory Retrieval

As opposed to the traditional polygraphic measures, the use of electroencephalography (EEG) and event-related potentials (ERPs) as a method to identify deception have become increasingly popular (Ambach & Gamer, 2018). EEG and ERPs are noninvasive and provide high temporal resolution of underlying cognitive processes applicable in the forensic, legal, and clinical fields (Luck, 2012). Due to the advantages of EEG and ERP techniques, the goal of this study is to observe the behavior and neural correlates of deception using an object recognition task and ERP components. Two phases of this experiment will be conducted, including the memory encoding phase and the memory retrieval phase. The memory encoding phase involves participants navigating a simulated apartment and locating target objects. The memory retrieval phase is an object recognition task, where participants are asked to tell the truth or lie regarding their memory of the target objects while wearing an EEG cap to record brain activity. We hypothesize deceptive responses will elicit a stronger response than the truthful condition. These results can provide valuable insight regarding the value of ERP techniques in the real world. For example, the memory testing paradigm in this study concerns target object recognition, which can be adapted to test crime-related knowledge through a Concealed Information Test (CIT) (Rosenfeld, 2019). Future research could measure deception detection by combining polygraphic measures with EEG techniques. These findings may further enhance the ability to detect deception in our society.

Daisy Hand

Advisor: Ariana Orvell

Assessing the Role of Physical Rituals and Distraction Techniques on Focus and Persistence in Young Children

Children are constantly in situations in which they must practice self-control–the ability to regulate one’s behavior to meet distal goals–but often struggle to do so. However, children can benefit from strategies that harness their attention or cognition in ways that help them focus on their long-term goal. For example, during waiting (delay of gratification paradigms), strategically redirecting attention by focusing on a fun toy, singing, or talking to oneself, helps children wait (Mischel et al., 1972). It is also possible that engaging in certain behaviors, before starting a self-control task, could be beneficial. Research with adults indicates that rituals—a fixed series of intentional, physical movements that is repeated several times—can improve behavioral self-control (Tian et al., 2018). Rituals are rigid and promote obedience to a set structure, which heightens self-discipline. Rituals have also been shown to work for children—regardless of whether their culture typically values them— one intervention delivered over the course of three months found that exposing children to games with a ritualized framing improved their ability to delay gratification, which was explained by increases in executive function (Rybanska et al., 2018). However, whether engaging in a short, novel ritual leads to improved self-control for children in a subsequent task is unknown.  The current research aims to investigate this issue to discover whether rituals benefit children in persisting at a boring work task. In our study,  children ages 6-9 are tasked with helping the researcher with an important job by playing a boring online peg-board game. They are shown a more fun game and told that they can take breaks from the important task at any point to play the other game. Children assigned to the ritual condition are shown a set combination of physical movements they must complete three times before starting the task. Framing the behaviors as conventional and rigid is theorized to help promote children’s self-control in the working task. In the control condition, children are prompted to create their own sequence of movements and only perform them once. We will then measure the time they spend on the peg-turning task, number of pegs dropped on the board, and the number of pegs locked onto the peg-board. We primarily hypothesize that children will work on the important task for longer after performing the ritual. Linking back to Mischel’s canonical findings, we will also assess whether children–regardless of condition–employ strategies spontaneously to help them persist in the boring task. For example, organizing the pegs by color or into shapes, as a way to make the task more fun. Therefore, we also predict that children who employ any type of persistence strategy will last playing the peg-board task for longer than those who don’t. Findings from this research will reveal useful methods for persistence and self-control in children. These methods can then be taught, improving young children’s capacity for focusing on any task.

Clare Hann

Advisor: Cora Mukerji

Associations Between Positive Childhood Experiences and Self-Esteem in LGBTQ Adults

Previous research has shown that LGBTQ adults report higher levels of adverse childhood experiences (ACEs) than cisgender, heterosexual adults (Schneeberger et al., 2014). ACEs have been associated with negative mental and physical health outcomes in both LGBTQ and non-LGBTQ samples (Felitti et al., 1998; Tran et al., 2022), which presents a challenge for LGBTQ adults who are already at risk of mental illness (Chakraborty, 2011). Research has been done showing that positive childhood experiences (PCEs) may promote psychological resilience by contributing to greater self-esteem in the general population (Kocatürk & Çiçek, 2023). However, associations between different types of positive childhood experiences and self-esteem among LGBTQ adults remain unclear. It is especially important to investigate PCEs during adolescence because this is when queer identity emerges and LGBTQ people begin to rely on community rather than family (Wilkerson et al., 2017).This study will test whether PCEs are associated with greater self-esteem in an LGBTQ population and explore the extent to which positive experiences specifically with caregivers, close friends, and/or adult role models in adolescence contribute to variation in LGBTQ adults’ self-esteem. We will use data from LGBTQ adults who participated in an online study that recruited a nationally-representative US sample. Participants self-reported demographics and completed questionnaires assessing their positive childhood experiences with caregivers, close friends, and other supportive adults (POS-DEV Retrospective Scales; Lopez et al., in prep) and their current self-esteem (Rosenberg Self Esteem Scale; Rosenberg, 1965). In line with previous studies in the general population, we hypothesize that the PCEs and self-esteem will be positively correlated among LGBTQ adults. As an exploratory aim, we will then characterize the relative contributions of PCEs from different support systems to self-esteem in adulthood. Findings from this study can help understand the impact that positive experiences in childhood have on the self-esteem of sexual and gender minority adults, and identify which social support systems might be particularly important in contributing to healthy development of self-esteem.

Masa Hasegawa

Advisor: Cora Mukerji

Assessing gender differences in the association between childhood unpredictability and mental health outcomes

Adverse Childhood Experiences (ACEs) refer to stressful and traumatic events that occur during childhood, such as abuse, neglect, and household dysfunction. Exposure to ACEs has been linked to long-term negative impacts on mental health and well-being in adulthood. Prior studies have revealed that the relationships among ACEs categories and resilience to internalising disorders differed by gender (Chen et al, 2021) and that gender could moderate the effects of childhood sexual abuse on risk of developing depression and PTSD (Gotschall et al, 2021). However, few studies have tested whether the interactions between specific dimensions of childhood adversity and psychological well-being in adulthood differ by gender. One of the key dimensions of ACEs is childhood unpredictability, which is characterised by instability and uncertainty in a child’s environment, often reflected in unstable social networks, inconsistent parenting, frequent moves etc. A recent study on Chinese adolescents found that gender moderates the relationship between environmental unpredictability and depressive symptoms, such that the association was stronger for women than men (Wang et al, 2024). This is likely due to gender differences in the kinds of survival strategies individuals employ under high-risk environments (Wang et al, 2024). In the current study, I will investigate whether there are gender differences in the associations between childhood unpredictability and mental health outcomes in a large, nationally-representative sample of US adults. Using data from self-report measures administered online, I will evaluate whether gender moderates the associations between childhood unpredictability and symptoms of depression and anxiety. Given prior research on gender disparities, I hypothesise that women who have experienced high levels of childhood unpredictability are more vulnerable to poor mental health outcomes than their male counterparts.

Lianna Pan

Advisor: Zhenlan Wang

A Cross-Cultural Study of Dialectical Themes in Chinese and U.S. Storybooks for Early Childhood

Children’s storybooks are cultural artifacts that distill simple moral truths and transmit values across generations. A large body of Western research has highlighted the influence of cultural artifacts—books, shows, and Disney stories—on children’s moral thinking and behavior (e.g., Lamoureux & Morling, 2012; Towbin et al., 2002). Moral development, however, has largely been formalized by Western theorists like Piaget and Kohlberg. While the stages of development are often considered universally applicable across cultures (Moon, 1986), there is a growing need to account for cultural variation in moral reasoning and its underlying psychology. Our project examines the philosophical differences in the moral lessons of Chinese versus U.S. children’s storybooks, focusing on dialectical thinking—a concept coined by Peng and Nisbett (1999) rooted in Chinese traditional thought. They identify three core principles of dialectics: change (ever-shifting states of being), contradiction (coexisting opposites), and holism (the whole is greater than the sum of its parts), which contrast with the three laws of Western logic: identity, noncontradiction, and the excluded middle. Dialectical thinking has broad implications for moral values and behavior: it influences conflict resolution, with dialectical cultures favoring mutual compromise and harmony, while Western approach leans toward retribution and one-sided resolutions (Leung, 1987); and it enables more holistic integration of attention, memory, and emotion during moral decision-making (Cheon, 2018).

Our study analyzes over 280 children’s storybooks, including a substantial number from China and the U.S., as well as others from broader Eastern and Western countries. We compare books along two axes: first, across the cultural-geographical divide of East and West, which represent differing degrees of dialectical versus formal logic, and second, over time within Chinese books, tracing from ancient myths and proverbs to contemporary stories to observe how moral values have evolved and how globalization has influenced them. These books, gathered from award winning lists, iRead foundation, and Chinese parent’s surveys, are intended for 3–5-year-olds. To investigate dialectical themes, we use qualitative coding conducted by trained bicultural coders who first identify each book’s moral lesson, then confirm them through intercoder reliability. From this, we developed a coding scheme based on dialectical principles: consistency or change in moral standards (reflecting contradiction and change), verbal and non-verbal feedback, outcomes of morally right behavior (measuring tolerance for social contradiction), and the clarity of proposed solutions.

In the future, we aim to move beyond storybook content (“what”) to explore children’s moral internalization (“how”). While children often focus on storybook’s surface features and overlook abstract themes (Walker & Lombrozo, 2016), research highlights effective interventions—using real-life stories, prompting explanation, and guided parental instruction. Our follow-up experiment will involve guided parent-child reading sessions to examine different forms of interaction shaping morality.

Carly Penn

Advisor: Anjali Thapar

Investigating Emotion Recognition Decline in Older Adults

As life expectancy increases in the United States, so do issues with cognitive ability experienced in later stages of life. An important area of cognitive decline is emotion recognition. Emotion recognition is the ability of individuals to recognize and process emotions, and is a crucial aspect of nonverbal communication. Difficulties in emotion recognition can significantly impact an individuals’ overall communication skills. Previous research has shown that emotion recognition decline within older adults is substantial for negative emotions, (i.e. sadness, anger) in comparison to positive emotions, in which little or no decline is often reported (i.e. happiness) (Murphy & Isaacowitz, 2010). Based on current research it is unclear why this decline in emotion recognition is seen. Many theories have been proposed however, they are frequently contradictory. Additionally, previous studies had several limitations. One major issue was that many studies utilized static images of facial expressions to test emotion recognition. This is not a realistic representation of how emotions are displayed and interpreted within the real world, as emotion recognition often involves other factors beyond simply a static facial expression. An additional limitation of previous studies is the fact that they in large part used images of younger adults, this could potentially be what has been leading to younger adults scoring higher in emotion recognition studies. The current study will examine these limitations and look into factors beyond age such as personality and IQ scores, to get a better understanding of why emotion recognition decline is seen in older adults.

Priyanka Regmi

Advisor: Thomas Le

Gendered racism, conformity to masculine norms, and Asian American men’s sexual assault perpetration

Sexual assault is an alarming issue worldwide, including in the United States. Data collected by The Rape, Abuse & Incest National Network (RAINN) reveals that, as of 2020, every 68 seconds, another American is sexually assaulted. While individuals of all genders, races, and ages are affected by sexual assault, CDC data shows that over half of women (53%) report experiencing sexual violence in particular. 

To address this issue, researchers have examined possible contributors to sexual assault. One important sociocultural, psychological factor associated with sexual assault perpetration is conformity to masculine norms. Masculine norms include ideas that men should have dominance over women (power over women) or possess multiple sexual partners (playboy).

Sexual assault has not only been linked to sexual gratification but also to asserting power and control over a vulnerable individual. Research suggests that men who experience oppression may be more likely to assert power and control over others to reclaim a sense of agency that they feel has been denied to them. However, studies related to masculine norm conformity have primarily involved samples from the WEIRD (Western, Educated, Industrialized, Rich, Democratic) population, limiting our knowledge related to sexual assault perpetration in other communities.

This study focuses on examining oppression in the form of gendered racism, which refers to the dual discrimination that Asian American men experience at the intersection of race and gender We aim to explore if gendered racism is associated with proclivity to perpetuate sexual assault, as well as if conformity to masculine norms mediates this association. These research questions will be assessed through running path analyses on previously collected survey data from a sizable sample of Asian American men.

Anadys Rodriguez

Advisor: Thomas Le

Examining the association between anti-fat bias and depression among queer men of color: Appearance comparisons as mediator

The present study aims to examine how anti-fat bias is associated with depression among queer men of color and whether this association is mediated by appearance comparisons. We hypothesize that a greater level of anti-fat bias will be associated with increased depression. We also hypothesize that appearance comparisons will mediate this association, such that greater anti-fat bias will be associated with greater appearance comparisons, which will then be associated with greater depression.

Research has shown that queer men are at increased rates of body dissatisfaction compared to straight men, with desires to be both leaner and more muscular (Tiggeman et al., 2007). Similar research has found that body image dissatisfaction has been associated with higher depressive symptoms, but it is difficult to generalize these findings to more diverse groups (Paans et al., 2018). Given the marginalization of queer men of color (Le et al., 2023), they may be even more susceptible to internalizing anti-fat bias, which may then be associated with elevated depressive symptomatology. Appearance comparisons, which are conceptualized as judgments of one’s appearance against others, including upward, downward, proximal, and distal judgments (Schaefer & Thompson, 2018), may mediate this association by supporting feelings related to anti-fatness and body dissatisfaction. These feelings may include a lack of muscularity or leanness compared to others.

Data will be collected through an online survey consisting of validated questionnaires and demographic questions. The survey will be created through Qualtrics and will also include two attention check items. Regression and mediation analyses will be executed to test the aforementioned research hypotheses.

Charlotte Scarlata

Advisor: Dustin Albert

The Gender Gap in Adolescent Internalizing Explained via Differential Susceptibility to Stress

It is well established in the existing literature on mood disorders that women and girls experience higher rates of internalizing and depression than boys and men. Longitudinal studies find that the gap in rates of internalizing reported by boys and girls emerges in early adolescence and peaks during young adulthood, before stabilizing throughout the rest of the lifespan. 

Research also suggests that increased exposure and sensitivity to various dependent and independent sources of stress is correlated with higher rates of internalizing and depression. Various theories -- including the diathesis stress model, ABC model (i.e. affective, cognitive, and behavioral), differential susceptibility to the environment theory of depression, and adaptive calibration models -- have described pathways through which stress influences an individual’s likelihood of developing psychopathology. Drawing on these models, our research aims to investigate how the interaction of stress and gender contributes to the adolescent gender gap in internalizing. After identifying a variety of stressors (e.g. social, community-level, physical, etc.), we will conduct multi-group path analyses to determine the relative strength of interaction between gender and stress susceptibility on internalizing symptoms experienced by a culturally diverse sample of adolescents. Our data will be drawn from the Parenting Across Cultures Dataset, which includes a large sample of children and adolescents from 9 countries across the globe. Identifying the mechanisms behind the gender gap in adolescent internalizing will also benefit efforts to understand the disparity between rates of depression in male and female adults, and improve treatments and interventions for mood disorders. Additionally, by utilizing a culturally diverse sample, our research will extend the existing literature to a global population, improving the generalizability and external validity of theories aimed at describing the gender gap in depression.

Maddie Seward

Advisor: Ariana Orvell

The Role of Rituals on Persistence and Self-Control in Young Children

Starting from a young age, children are required to practice self-control. Self-control refers to an individual’s capacity to prioritize more distal goals over immediate ones (Fujita, 2011). Research shows that engaging in a ritual, a sequence of specific actions that are repeated, can improve self-control in adults (Tian et al., 2018). Rituals are theorized to improve self-control by heightening the sense of self-discipline, which in turn drives a feeling of self-control. However, we do not know if exposing children to a short, novel ritual can help them exert self-control in a subsequent task. This research looks to bridge this gap by investigating the impact rituals have on children’s ability to persist during a task requiring self-control. Children ages 6-9 are asked to help the researcher with an important job by playing a boring online game where they need to drop pegs onto a virtual pegboard and lock them into place by clicking three times. They are then shown another game and told that they can take breaks from the important task to play a new, more fun game, when they want to. Children assigned to the ritual condition are shown a video where they are asked to do a set of ritual movements three times before starting the task. Children assigned to the control condition are prompted to create their own movements, which are not repeated. The time they spend on the boring task, the number of pegs dropped on the board, and the number of pegs locked into place are measured. I hypothesize that children will persist on the important task for longer and lock in more pegs after performing the ritual. There is also research that shows among 6-year-olds and 4-year-olds, older children maintain focus on a boring task for longer, demonstrating growth in self-control as they age (White et al., 2017). Given this, I predict that age will have a main effect on self-control, with children ages 8-9 exhibiting better self-control than children ages 6-7. Understanding self-control and persistence strategies could help students stay focused on tasks and persevere in school.

Mahveen Wani

Advisor: Zhenlan Wang

Evaluating Moral Development in Children’s Storybooks: A Cross-Cultural Study

Dialectical thinking, rooted in Chinese philosophical traditions, emphasises the interconnectedness of opposites and the naturalness of change. This cultural pattern has been observed in both emotional and cognitive domains: East Asians tend to show greater tolerance for emotional ambivalence (Ma & Miyamoto, 2019), and Chinese individuals are more likely to engage in holistic cognition, attending to background and context when interpreting scenes (Nisbett et al., 2001). Culture also plays a fundamental role in children’s moral development, as studies have shown that Indian and Chinese children are more likely to prioritise interpersonal obligations and social harmony over individual rights in moral dilemmas (Miller & Bersoff, 1992; Lee et al., 1997; Shweder et al., 1987).

This project explores whether portrayals of moral ambiguity in children’s storybooks reflect broader dialectical patterns in Chinese moral socialization through a cross-cultural comparison of stories authored by Chinese and Western writers. We will analyse a total of 180 storybooks (90 written by Chinese authors and 90 written by Western authors) to develop a culturally informed coding rubric that captures how dialectical thinking is reflected in the moral judgment throughout the books. We hypothesize that the moral standards in books written by Chinese authors would be more flexible/inconsistent than the moral standards in books written by American authors. Focusing initially on US-based storybooks, I am identifying themes related to moral development, including the explicit moral lesson, consistency of moral standards, verbal and non-verbal feedback following morally right behaviour, and the clarity of suggested solutions. These themes will inform the development of a coding rubric that captures culturally embedded moral messaging.  This work will shed light on how moral and cultural values are transmitted through everyday educational tools and contribute to broader research on culture and development.

Sasha Weisman

Advisor: Laurel Peterson

Exploring Smoking and Vaping Prototypes and Behavioral Willingness in Emerging Adult College Students: Applying The Prototype Willingness Model to Nicotine Prevention

Both tobacco cigarette smoking (smoking) and electronic nicotine cigarettes (vaping) have detrimental health effects. This is especially a cause for concern among emerging adults, who have particularly high prevalence rates (Patrick, Miech, Johnston, & O’Malley, 2024). Smoking and vaping are leading health concerns on college campuses as over a quarter of undergraduate students have engaged in nicotine use (American College Health Association, 2024).  Social cognitions play a role in smoking and vaping behavior. The Prototype Willingness Model provides a framework for understanding how social reactivity leads to health risk behavior via prototypes, one’s ­image of a typical person engaging in a behavior, ­and behavioral willingness, one’s openness to engaging in a behavior when a social opportunity arises. Past research demonstrates that favorability of substance use prototypes inform behavioral willingness, which in turn predicts future substance use (van Lettow et al., 2015; Todd et al. 2016). Most research has applied the Prototype Willingness Model to smoking behavior among adolescents, and additional research is needed to expand use of the model to examine vaping and smoking behavior in emerging adults. National research suggests that both smoking and vaping are sources of nicotine dependence among emerging adults, but that they perceive vaping as more socially acceptable (Romm et al. 2024). However, almost no research has directly compared the prototypes and willingness that emerging adults have regarding smoking and vaping.

My research will directly compare emerging adults’ smoker and vaper prototype favorability and smoking and vaping willingness. Additionally, I will examine the relationship of smoking and vaping prototypes on smoking and vaping willingness using a dataset of emerging adult college students. Approximately 300 college students reported their smoking and vaping prototype favorability as well as their willingness to engage in both behaviors. I hypothesize that both prototype favorability and willingness for vaping will be higher than favorability and willingness for smoking. Additionally, I hypothesize that prototype favorability for both smoking and vaping will be positively associated with willingness for the respective substance. This study will simultaneously tie together and expand upon the current research on smoking, vaping, and the Prototype Willingness Model to establish a more comprehensive understanding of emerging adults’ social cognitions regarding smoking and vaping, which in turn can better inform potential intervention strategies and college health resources.

Ariel Zhao

Advisor: Cora Mukerji

The Impact of Childhood Unpredictability on Adult Anxiety: Safety as a Moderating Factor

Anxiety is one of the most prevalent mental health issues worldwide, and early life stress plays a critical role in its development. Previous research indicates that low social support, poor family satisfaction, and high school pressure can contribute to the onset of anxiety in childhood and adolescence (Roberts et al., 2009). Additionally, parental worry, experiential avoidance, and intolerance of uncertainty can also contribute to childhood anxiety (Aktar et al., 2017), underscoring the importance of early experiences. In particular, childhood unpredictability—a form of adverse childhood experiences (ACEs) that can include housing instability (e.g., frequent relocations and unstable living arrangements)—may be linked to increased anxiety and depression throughout life (Gottfried & Hough, 2023). In contrast, higher levels of positive childhood experiences (PCEs) are associated with lower anxiety risk and may independently promote mental well-being, even in the presence of cumulative ACEs (Bunting et al., 2023; Bethell et al., 2019). Although studies have linked cumulative ACEs to adult anxiety and suggested that cumulative PCEs can mitigate these effects (Qu et al., 2022), few have focused on identifying specific dimensions of ACEs and PCEs that shape anxiety risk. In this study, I will investigate the relationship between childhood unpredictability and adult anxiety symptoms, with a focus on whether a sense of safety—a key dimension of PCEs—moderates this association. Previous findings suggest that adolescents who felt safe and protected by an adult at home reported lower levels of depression and anxiety, as well as better overall mental health (Samji et al., 2024). Based on this evidence, I hypothesize that (a) higher childhood unpredictability will be associated with greater anxiety symptoms in adulthood, and (b) that childhood safety will moderate this relationship, such that safety will buffer the negative effects of unpredictability on anxiety symptoms. Data will be drawn from the Life Experiences and Outcomes (LEO) Study.

To address my research questions, I will use hierarchical regression analysis. First, I will enter childhood unpredictability as an independent variable to assess its direct association with anxiety symptoms. Next, I will include covariates—age, gender, and current stress level—to control for potential confounding effects. Then, I will add childhood safety, a positive childhood experience (PCE), to evaluate its unique contribution to anxiety symptoms. Finally, I will test whether childhood safety moderates the effect of unpredictability on adult anxiety. This proposed study has important clinical implications, as it may help determine whether childhood unpredictability significantly predicts adult anxiety symptoms and whether fostering childhood safety could serve as a protective factor against the development of anxiety.

Gioanna Zhao

Advisor: Thomas Le

K-Pop, Asian media, and Asian American adults’ depression systems

Over the past two decades, K-pop has evolved from a niche genre to a popular trend in the global entertainment industry. For many Asian Americans, this rise in popularity has provided much-needed representation in mainstream media, offering a sense of cultural affirmation that has historically been lacking in Western entertainment. Seeing Asian artists succeed instills pride and a stronger connection to one's heritage. K-pop communities also create spaces where fans can celebrate their cultural background together, forming social bonds that further strengthen belonging. However, this representation can also present a narrow and idealized version of Asian identity, reinforcing rigid beauty standards that may contribute to psychological distress. Thus, while K-pop offers visibility, the nature of that representation can have both nuanced implications for mental health.

The way Asian Americans internalize these media portrayals is deeply connected to their sense of racial identity. The present study thus examines K-pop media consumption and Asian media consumption as independent variables, depressive symptoms as the dependent variable, and internalized racism and racial collective self-esteem as mediators. This research is crucial in understanding how cultural representation in media intersects with mental health outcomes for Asian Americans. By examining how internalized racism and racial collective self-esteem mediate the association between K-pop consumption and depression, this study will provide insight into the complexities of cultural engagement. We hypothesize that increased consumption of K-Pop and Asian media may be associated with increased racial collective self-esteem and decreased internalized racism, which would subsequently be associated with decreased depression. These research questions will be assessed utilizing regression and mediation analyses on survey data collected from a sizable sample of Asian American adults.