Summer Science Research | 2021 Program

Mortimer Cavanah

Advisor: Maja Šešelj

Exploring the Applications of Deep Learning in Dental Anthropology

The identification of dental growth stages in immature individuals is widely used to estimate chronological age and/or assess skeletal maturity in many academic and professional fields (e.g., forensic anthropology, bioarchaeology, biomedicine). The current process used for identifying these dental stages involves individual assessors hand-scoring dental development based on non-metric, qualitative criteria-- consuming large amounts of both time and human labor. Much of this time and labor consumption could be reduced by using deep learning techniques to develop a program capable of identifying dental growth stages. By using Google’s deep learning framework TensorFlow, this research project will focus on developing and curating a dataset of jaw radiographs and then utilizing this dataset to train a deep learning algorithm to recognize dentition and dental growth stages via supervised learning. This project is an exploration into determining how to make qualitative methods of scoring ‘digestible’ and recognizable to artificial intelligence in order to produce results consistent with human scoring, while ideally reducing time and labor costs, as well as improving reproducibility and accuracy.

Lana Giha

Advisor: Tamara Davis

Exploration of Methylation Maintenance at Imprinted Genes in Methyltransferase Mutant Mice

Our lab explores imprinted genes which are exclusively expressed from one inherited allele despite inheriting two alleles. The expression of one allele depends on its parental origin. In some cases, the maternally inherited copy may be expressed and in other cases the paternally inherited copy may be expressed. DNA methylation, the addition of a methyl (CH3) group by DNA methyltransferase, impacts the ability of the DNA to be transcribed. As a result, differential methylation of the DNA determines the expression of imprinted genes and creates differentially methylated regions commonly referred to as DMRs. There are primary DMRs which are inherited from gametes at fertilization and secondary DMRs at which differences in methylation are acquired during embryo development.

Previous work done by our lab has suggested that methylation is better maintained and more consistent at primary DMRs in comparison to secondary DMRs. DNA methyltransferase is responsible for maintaining methylation and promoting its stability, yet it appears to function differently at primary versus secondary DMRs. We would like to continue looking into methylation maintenance at imprinted and non-imprinted genes to understand why that is the case.

This project focuses on the methylation patterns of primary DMRs versus secondary DMRs in Dnmt 1 mutant mice. This will be explored using the methods of bisulfite mutagenesis, PCR, gel electrophoresis, DNA extraction, and DNA sequencing. Bisulfite mutagenesis converts unmethylated cytosines to uracil, allowing them to be distinguished from methylated cytosines which would remain unchanged. The mutagenized DNA can be used in PCR, Polymerase Chain Reaction, to amplify specific primary or secondary DMRs. The product of the PCR is analyzed by gel electrophoresis to confirm we amplified the sequence of interest. A gel extraction is performed to purify the final product. The purified final products will be pooled and submitted for Next Generation amplicon sequencing. I will then analyze the resulting sequences to determine how the Dnmt 1 mutation impacts the methylation at primary versus secondary DMRs, as well as at non-imprinted genes.  

Keywords: Imprinted genes, DNA methylation, DNA methyltransferase, primary DMR, secondary DMR, bisulfite mutagenesis

Madison Kearns

Advisor: Crystal Reynaga

Comparative Analysis Of Quadrupedal Anuran Limb Morphology and Forward Walking Locomotion

In the Reynaga Lab we are studying the changing morphology and locomotion patterns in two species of quadrupedal anurans, Phyllomedusa hypochondrialis and Phrynomantis bifasciatus. This research analyzes the ways in which varying limb dimensions affect the way a frog accelerates and decelerates to move their center of mass. Anurans have many features that enable them to jump efficiently, such as strong back legs and smaller bodies. In addition, previous work suggests walking frogs have evolutionarily altered their body composition, creating a more even ratio between fore- and hind limb length. However, in order to compensate for slight limb asymmetry some frogs maintain a more extended forelimb and a crouched hindlimb posture. In comparison to the crouched limb posture found in some walking frogs, certain species adopt a more sprawled posture when moving. However, it is unclear how sprawled or crouched postures may affect walking, as opposed to a more upright and erect posture.We use 3D high speed videography coupled with 3D ground reaction force plates to measure the forelimb and hindlimb reaction forces. The raw data is then contrasted against other species to understand the function of each limb during the stride. Using measurements of center of mass displacement, force during forward locomotion, and change in joint angles within the fore- and hindlimb we can compare the variation across species that have evolved the ability to walk quadrupedally. Overall, the research conducted this summer will continue to expand on the understanding of how quadrupedal gaits can be achieved despite the fact that the anuran morphology is specialized for jumping.

Isabelle Kuszyk

Advisor: Crystal Reynaga

Investigating How Limb Length Disparities Affect Red-Banded Rubber (Phrynomantis Bifasciatus) Frogs Walking Gait

Frogs are mostly known for their magnificent jumping ability; however, some species walk quadrupedally, such as the red-banded rubber frog. A previous study analyzed the walking and running gaits of a specialized quadrupedal walking frog species and noticed depending upon which metric they used, it was hard to classify whether their gait was indeed a walk or not. The results suggested that the quadrupedal frogs could use a walking or running gait depending on what factors were studied. For instance, when the researchers calculated the kinetic and potential energies of the frogs, it showed the frogs used a running gait but when examining the footfall patterns, the frogs used a walking gait. However, previous studies have not analyzed the difference in forces applied by the fore- and hindlimbs, so it is not clear how those limbs affect propulsion. We will study how the forces applied are characterized relative to limb morphology. Other organisms, such as geckos, have developed quadrupedal gaits despite slight uneven limb lengths. Researchers have shown how the forces and limb function can differ between the fore- and hindlimb in the lateral and fore-aft direction of geckos limbs. Generally, frogs have a greater disparity between limb lengths than geckos, which is why we will test how substantially longer hindlimbs affect frogs’ gait. Our research will determine if quadrupedal frogs have adapted into efficient walkers based on their anatomical constraints. I hypothesize that the force exerted from the front and back limbs will be similar. To test this hypothesis, we will study frogs walking across 3D ground reaction force plates while recording them with high-speed video analysis. We will digitize videos to help us determine if the front or hind limbs exert different forces or similar amounts. Our research can help us understand how different species of frogs have developed the ability to walk independently from their ancestors.

Yeipyeng Kwa

Advisor: Gregory Davis

The Role of JH Signaling Aphid Reproduction Polymorphism

Aphids are known to exhibit reproductive polyphenism, a type of plasticity which allows them to switch between cyclical parthenogenesis (asexual) and sexual reproduction. Female asexual viviparous aphids, called virginoparae, when exposed to short nights (and long days) and higher temperature (summer) conditions, produce female embryos that are likewise asexual and viviparous. However, when these females are exposed to long nights (and short days) and cooler temperatures (fall conditions), a special asexual and viviparous female known as the sexupara is produced, and this female produces the single generation of sexual females and males in the aphid lifecycle; these sexual females lay eggs that are able to withstand winter tempertures, an advantage for aphid species in regions known to have severe winters. Although photoperiod is known to be the environmental cue that specifies reproductive fate, received by mothers and transmitted to embryos, the nature of this maternal signal has yet to be identified.

What we do know is that this maternal signal is an asexual promoting signal, and although the identity of this signal is not yet known, Juvenile Hormone (JH) is considered one of the leading candidates based on correlative data as well as results from tests of sufficiency: Asexual aphids express higher levels of JH than sexual aphids; JH and JH analogs, when topically applied to sexuparae, are sufficient to induce her embryos to take on an asexual fate. However, further investigations have shown that maternal JH is not necessary to specify asexual fate. My hypothesis, therefore, is that embryonic JH functions to specify fate in aphid embryos during embryogenesis and is induced by a different signal which is transmitted from the mother to the embryos.

 To better understand the role that JH plays in specifying reproductive fate, I will first be determining a reliable method for measuring JH expression in pea aphids (Acyrthosiphon pisum), which will then enable me to measure JH signaling in embryos of asexual aphids versus embryos of sexual aphids. A possible outcome is that embryos of asexual aphids express higher levels of JH than embryos of sexual aphids, which will establish JH as a signaling molecule that specifies fate in embryos during embryogenesis.

Rebecca Li

Advisor: Gregory Davis

Establishing a Neurophysiological Basis for the Reproductive Polyphenism in Pea Aphids

The pea aphid, Acyrthosiphon pisum, exhibits a reproductive polyphenism wherein the species is cyclically parthenogenetic due to seasonal changes in photoperiod. Under summer's short-night conditions, A. pisum displays viviparous parthenogenesis (i.e. asexual females give live birth to another generation of asexual females). In the fall, in response to long nights, viviparous asexual females give birth to sexuparae, which are a form of viviparous asexual female that gives birth to sexual females and sexual males. These sexual females later reproduce by mating with males and laying fertilized eggs that can overwinter.

We seek to investigate the nature of the maternal signal that specifies sexual versus asexual fate during the embryonic development of A. pisum. It is hypothesized that this signal is asexual-promoting and originates in Group I neurosecretory cells (Group I NSCC), which are found in the dorsal anterior region of the brain.

Previous investigations have demonstrated that it is the photoperiod-induced state of the asexual mother, experienced pre- and post-natally, that determines the reproductive fate of her own offspring. For example, an aphid becomes a sexupara if it is exposed to long night conditions just prior to birth. Evidence indicates that the sexupara’s developing progeny then become sexual because they are not instructed to become asexual (i.e., sexual fate is the default). Neural microcautery experiments in the aphid Megoura viciae suggest that Group I cells are necessary to specify asexual offspring (i.e. in the absence of this signal, sexual offspring are produced), and thus that the signal is asexual-promoting.

Given that these experiments were performed over four decades ago — and in a different aphid species — we aim to establish the existence of an asexual-promoting maternal signal in A. pisum through functional disruption of the signal. A variety of techniques will be explored, including electrocautery and surgical ablation of the Group I NSC, and blocking light to the head capsule.

Penelope Northing

Advisor: Thomas Mozdzer

Mapping Functional Traits to Genotypes of P. australis in a Common Garden

Coastal wetlands are important to study in the context of global change because they sequester more carbon than any other ecosystem while simultaneously being influenced by sea level rise, species invasion, and other effects. Recent advancements in the field of coastal wetland ecology indicate that the invasive Eurasian perennial grass, Phragmites australis, may experience selective pressure from different global change factors, causing rapid evolution. This finding indicates that rapid evolution on a population-level could be an important process to consider when employing restoration and management strategies to remove P. australis in the coastal wetlands of eastern North America. In order to determine whether or not populations of P. australis are evolving due to global change, it is necessary to determine the relative plasticity and heritability of functional traits. This summer, my project seeks to answer the question of how different genotypes of P. australis correspond to functional traits by mapping the relationship between traits and genotype, the data from which will inform the long-term heritability study that Dr. Mozdzer is conducting over the next few years. This project utilizes an experimental common garden set-up with 300 unique genotypes of P. australis harvested from the Smithsonian Environmental Research Center, Parker’s Creek, and the Global Change Research Wetland in Edgewater, Maryland. I will be measuring the height, basal diameter, photosynthetic rate, nitrogen and carbon content, specific leaf area, and other functional traits of the P. australis plants in the garden. Ultimately, the results of this project will help contribute to a growing body of knowledge about P. australis' impact as an invasive species in the marshes of eastern United States, which could aid scientists and policymakers in improving practices and policies for restoring and managing our precious wetlands. Proper management of P. australis has the potential to not only save coastal wetland ecosystems, but help fight climate change by making the most of their carbon capturing abilities and other vital ecosystem services.

Camille Pastrana

Advisor: Sydne Record

Host-Parasite Dynamics of the Mistletoe Viscum alba

Parasitism is a form of species-species interaction in which one species benefits from the other species at the expense of the other species. Certain plants are considered parasitic based on their ability to feed directly on the nutrients and water from either the roots or the shoots, the xylem, of a host plant. By observing the population dynamics of the parasitic plant, one can gain general knowledge about the host plant and its relationship with the parasite. In this study, we specifically look at a species of the parasitic plant that is mistletoe, Viscum alba, in a research forest located in Silwood Park, England. We ask how the positioning of V. alba on the host plant influences the mistletoe survival, growth, and reproduction. We hypothesize that the lower the mistletoe is on the host plant, the better access it would have to the water and nutrients in the host plant based on hydraulic constraints. From 2014 to 2021, digital images were taken of various trees containing V. alba on their branches and each image was digitized, taking measurements on the number of individuals on each tree, the size of each individual, whether or not individuals were reproductive, and how high up on the tree each individual was. From this information, integral projection models will be made to look at population projections of mistletoe. Through these models, we can learn about the varying population dynamics of V. alba, and gain general knowledge of host-parasite dynamics.

Clementine Payne

Advisor: Tamara Davis

Comparison of Methylation at Imprinted and Non-Imprinted Gene

During development, both maternal and paternal DNA contributes to an embryo's genome. Much of the development of an organism is regulated by both the maternal and paternal copies of these genes. However, when a gene is imprinted, only one of these two parental copies is expressed. Imprinted expression is regulated through epigenetic modification or DNA methylation, the addition of a methyl group (-CH3) to cytosine in a CpG dinucleotide. This change in DNA chemistry affects the expression of the gene. The methylated copy is typically silent while the unmethylated copy is expressed. Parent of origin-specific differential methylation patterns acquired during gametogenesis, primary differentially methylated regions (DMRs), are maintained throughout development by DNA methyltransferase 1 and have proven to be stable across development. In contrast, methylation patterns are less stable and asymmetric at secondary DMRs, sites at which methylation is acquired during embryonic development. These results suggest that epigenetic modifications acquired during post-implantation development are maintained differently suggesting DNA methyltransferase 1 works less consistently at these sites.

To assess whether the variability in DNA methylation patterns at secondary DMRs are a unique feature of these loci, it is important to assess the methylation at both imprinted and non-imprinted loci.  The aim for this study is to analyze DNA methylation at non-imprinted sequences to be compared to the profiles which have been observed at imprinted loci. Our hypothesis is that these non-imprinted sequences will have similar methylation profiles to the primary, gametic, DMRs, consistent with what is known about DNA methyltransferase activity, while looking different from the secondary, post implantation, DMRs.

We are characterizing the methylation dynamics at non-imprinted genes. Of the three genes analyzed thus far, two, ZFP553 and Hnf4a, have methylation patterns consistent with our hypothesis; both have very stable methylation patterns similar to primary DMRs associated with imprinted genes. In contrast, Glut3 exhibited methylation patterns which were less consistent than primary DMRs while being more consistent than secondary DMRs. These data suggest the need for broader analysis therefore we are analyzing additional loci to further inform our study.

Lili Randolph

Advisor: Thomas Mozdzer

Quantifying Genotypic Recovery of a Foundational Wetland Plant Species

Wetlands are one of the most effective biomes for carbon sequestration and provide valuable ecosystem services that make their welfare valuable to the environment and its inhabitants. Biodiversity of different species within these wetland ecosystems and within the species itself (intraspecific diversity) promotes a healthy biome and fluctuates greatly depending on external factors like climate change, introduction of invasive species, and nutrient enrichment. In 2004, researchers working on the TIDE project began adding nitrogen to each incoming tide of two field sites to simulate coastal eutrophication. In 2009 an additional field site was added. Samples were collected from two additional unfertilized sites to act as controls. During this process of eutrophication, researchers expected to see phenotypic responses in the Spartina such as a shallower root structure and increased height above ground. In addition to these phenotypic responses, researchers also noticed that the genotypic diversity of these plants decreased. Researchers have since stopped adding additional nitrogen to these sites with the expectation of stopping the eutrophication process, allowing Spartina’s genetic diversity to increase in the affected areas. I will be quantifying how much the genetic diversity of Spartina alterniflora has shifted in our field sites during the recovery from excessive nitrogen enrichment using microsatellites, analyzed in Geneious, to identify Spartina genotypes, and using GenAlEx calculate genetic relatedness of all Spartina samples. We will then use ANOVAs to compare genotypic diversity and genetic relatedness across fertilized and unfertilized creeks. We will also compare genetic diversity and relatedness before fertilization, at the end of fertilization, and after three years of recovery without nitrogen addition. By doing this, we can quantify the rate and level at which Spartina recovers from nitrogen excess and how to proceed with the management of nutrient enrichment in wetland areas.

Frances Romero

Advisor: Thomas Mozdzer

Re-evaluating Phragmites and Phragmites management in terms of coastal resilience

The question of my SSR research project is how management of the invasive marsh grass Phragmites australis affects coastal marsh resilience. Marshes are some of the most effective ecosystems at storing carbon. Climate change is increasing sea level rise at a rapid pace, and marshes need to keep pace with this rise in order to continue functioning as a carbon sink.  Phragmites australis is a grass species that is invasive to North America and has been linked to biodiversity loss in marshes as well as changes in biogeochemical cycling. The United States spends over $4.6 million on Phragmites management yearly, primarily via the spraying of glyphosate. While there are many studies on the role that Phragmites plays in marsh ecosystems, there is little known about the effectiveness of spraying glyphosate for Phragmites management and how it affects marsh resilience to sea level rise. The focus of this study is to assess the management practices of Phragmites australis in terms of coastal marsh resilience to determine if we need to re-evaluate when and where we treat Phragmites. My hypothesis is that Phragmites will increase blue carbon pools as well as ecosystem resilience in comparison to the native grass species. In addition, we hypothesize that Phragmites invasion will increase decomposition rates and methane emissions which could offset these predicted carbon gains. Taking both of these predictions into account, I hypothesize that management of Phragmites will decrease soil carbon pools and that restored wetlands will have the lowest resilience to sea level rise and lowest blue carbon pools. The broader impacts of this research are crucial because we spend millions of dollars a year on phragmites management, and re-evaluating how we manage Phragmites in a way that effectively restores marsh resilience, is crucial for maintaining marshes ability to store carbon in the face of climate change.

Amara Saha

Advisor: Adam Williamson

Molecular Insight into the Initiation of Phagocytosis

Transmembranal engulfment receptor proteins such as Draper in Drosophila melanogaster and its mammalian homolog Megf10 act as molecular bridges which connect phagocytes with their targets through ligands. The activation of these receptors initiates a cytosolic signaling program that ultimately leads to engulfment of the target cells. However, the molecular geometry of these receptors is not well understood. Such knowledge of receptor configurations may provide critical insights into their function and enhance our understanding of how they interact with other proteins to initiate phagocytosis. In order to define the geometry of the receptors, I will conduct a dimerization experiment to understand whether Draper/Megf10 molecules interact with each other in cis, i.e. on the same cell. To study this protein-protein interaction, I will perform a co-immunoprecipitation of modified Draper-GFP and Draper-FLAG proteins using GFP and FLAG specific antibodies. If Draper dimerizes in cis, the anti-GFP western blot would show a band for FLAG and an anti-FLAG blot would show one for GFP.

Studies in the field suggest that Draper is phosphorylated by kinases such as Src42A to become activated and initiate phagocytosis. I will use biochemical assays to understand aforementioned receptor interactions that can further give insight into events such as post-ligation microclustering that favor the activation. In addition, other molecules such as Shark, a non-receptor Tyrosine kinase, can recognize activated Draper to commence downstream signaling processes and complete phagocytosis. The initial dimerization study can enable room for experiments to understand Draper’s interaction with Shark and provide a platform to understand their collaboration in initiating phagocytosis. Collectively, my work will provide molecular insight into ancient mechanisms underlying receptor-mediated immunity

Katrina Sparks

Advisor: Adam Williamson

Mechanical control of phagocytosis

Mechanobiology is a field that bridges physics and biology to understand how mechanical cues instruct and regulate living systems. Phagocytosis is the process by which immune cells called phagocytes engulf their targets, including dead cells and pathogens. Well-characterized “eat me” signals on the surface of dead cells serve as chemical ingestion signals for phagocytes, but how the dynamic forces and mechanical properties of targets and the environment control phagocyte behavior remains unclear. My guiding question this summer is whether or not phagocytic eating behavior is determined by the stiffness ratio between the target and environment. Recent work points to phagocytes’ enthusiasm toward engulfing denser particles (e.g., dead cells that are denser than living cells), but I hope to learn how phagocytic proficiency changes over a range of target-to-environment stiffness ratios.

I hypothesize that larger ratios of target-to-environment stiffness will facilitate higher levels of engulfment, whereas lower ratios will inhibit engulfment. I will vary target stiffness by feeding phagocytes soft round beads with different, known densities. I will vary environmental stiffness by growing the phagocytes on substrata of different densities made from polydimethylsiloxane (PDMS), a soft elastomer. This cell biology experiment, which I will image on a confocal microscope at the University of Delaware, may provide insight into the fundamentals of how phagocytes interact with their environment. Specifically, my work will illuminate whether phagocytes discriminate between possible targets based on measurements of target stiffness alone, or, rather, the stiffness ratio between a target and their environment. This work is a collaboration between the Cheng and Williamson labs. In addition to providing insight into the mechanical control of phagocytosis, my work will also help foster a growing cross-disciplinary collaboration at ��������.

Nuan Zhang

Advisor: Crystal Reynaga

Investigating How Compliant Substrates Affect the Biomechanical Properties in Hopping Cane Toads

Cane toads, Rhinella marina, use hopping as their primary mode of movement. They can hop shorter distances over longer bouts of time. There are another species called Osteopilus septentrionalis, also known as Cuban tree frogs, that jump fast and far distances. Previous work has shown that the Cuban tree frogs do not actively change muscle activation patterns jumping off springy substrates, and can utilize the elastic energy stored in their tendons. In Dr. Reynaga’s lab, we are interested in investigating the biomechanical differences between hoppers (cane toads) vs. jumpers (Cuban tree frogs) while jumping off compliant substrates. Extensive work has shown that cane toads can modulate and tune their landing motor patterns relative to their environment. So for this project we hypothesize that: 1) cane toads may be able to adjust muscle activation patterns when jumping off different springy substrates and 2) cane toads may not be able to utilize the elastic energy stored in the substrate as effectively as the tree frogs. This research will help us to understand how different frog species utilize different muscle recruitment strategies when facing perturbations in the environment. High-speed videography is used to film the jumping performances of cane toads on a physical compliant substrate. The videos will be digitized and analyzed to characterize the crucial parameters including joint angles, the velocity of limb extension, and energy output. Moving on we will observe the muscle activation patterns and compare the results of the two species to determine the impact of perturbations in the environment.

Angie Bonanno

Advisor: Arlo Weil

Using Structural and Paleomagnetic Data to Explore Hypotheses of Mechanisms for Laramide Deformation

The Laramide belt is located in the Cordilleras of western North America and is constrained geographically from central Montana to southern New Mexico. The Laramide belt is characterized by thick-skinned, contractional deformation that is dated to the Late Cretaceous to Paleogene. Compared to other mountain ranges, the Laramide has some unusual traits: a variety of orientations to the systems individual mountain ranges, localized and isolated basins, and a location far inboard from its associated active margin. Additionally, the tectonic evolution of Laramide deformation likely involved flat-slab subduction caused by the positive buoyancy of a hypothesized oceanic plateau. I will be working with Dr. Arlo Weil and fellow student Allison Velasquez in order to better understand the deformation history of the Laramide. Our exploration will involve fieldwork in southern Montana and the “four-corners” region, looking at patterns of deformation found in individual Laramide ranges to test existing hypotheses of the tectonic evolution of the belt. We will characterize the orientation and distribution of shortening directions and how these orientations relate to the geometry of the studied Laramide structures. To do this, we will measure mesoscopic structures in the field (such as minor faults, stylolites, fractures, etc.) to estimate paleo-stress directions, as well as collect core samples to measure their anisotropy of magnetic susceptibility (AMS) as a proxy for paleo-stress directions, and paleomagnetism to constrain any vertical axis rotation. Ultimately, we hope to use this data to test hypotheses regarding mechanisms of stress transmission during Laramide deformation.

Bethan Lodge

Advisor: Pedro Marenco

Geochemical investigation of the microbialite-bearing Notch Peak Formation at Lawson Cove, Utah

The Notch Peak Formation is located in west central Utah and consists of the Hellnmaria, Red Tops, and Lava Dam members.  The formation is Late Cambrian in age (~500 million years old).  The rocks in this formation are primarily marine dolomites with intervals of poorly-exposed siliciclastics.  The Notch Peak Formation is well-known for its abundance of microbialites—rock structures built by the activities of microbial mats.  Microbialites used to be much more common before the evolution of animals, but are rare today.  The Cambrian represents a transitional period during which animals were on the rise and microbialites were on the decline. Thus, these rocks represent a record of this important change in the history of Earth’s oceans. We set out to better understand this transition by studying the geochemistry of the microbialite-bearing intervals of the Notch Peak Formation in order to investigate the marine environmental conditions that allowed for the formation of microbialites.

We collected rock samples from the upper part of the Hellnmaria and the lower and middle parts of the Red Tops Member from the Notch Peak Formation at Lawson Cove, Utah. The samples were collected in approximately 1.5 meter intervals over a total range of 56.5 metres, which will allow for the production of a high resolution elemental and carbon isotopic dataset from these rocks.  From these samples we will create a chemostratigraphic column, analysing the inorganic and organic carbon isotopic content of the samples, alongside elemental data (in particular major elements Ca, Mg; minor elements Fe, Mn, Sr; and trace elements U, Th) to interpret changing environmental conditions during this interval.  Better understanding the diagenetic processes which these rocks have undergone and their chemical composition will allow for correlations to be identified between the results and will allow us to make inferences about the environment in which the rocks were deposited.

Sandra Melgar

Advisor: Katherine Marenco

Fossil Communities Associated with Microbialites in the late Cambrian Notch Peak Formation, Utah

My project will focus on microbialites that are preserved in rocks of the Notch Peak Formation, which formed in a shallow-water marine environment during the late Cambrian (~500 million years ago). During this time photosynthetic microbes lived on the seafloor forming sticky mats. As sediment accumulated on top of the mats it prevented sunlight from reaching them, and the mats grew over the sediment. This process of upward growth formed thin layers of sediment that became cemented together by crystals that precipitated under the conditions of the growing mats. Over time these layers accumulated into dome and branching structures, known as microbialites, that are preserved as rocks. Living nearby and in association with the microbial mats were multicellular organisms. When these organisms died their shells accumulated along with the sediment on and around the microbial mats. In my research I will test the hypothesis that some organisms interacted directly with the mats and others lived independently of the mats on the surrounding seafloor. In order to do this, I will compare the fossils that are preserved within the microbialites to those preserved in the surrounding sediment. I collected samples from four distinct microbialite units in the Notch Peak Formation in western Utah in June 2021. I will use a variety of lab techniques to compare the microbialite and non-microbialite portions of my samples. For example, I will prepare thin sections and acetate peels to look at microscopic fossils and sedimentary features. I will also use polished slabs and rock cores drilled vertically into the samples to look at larger scale features. Studying the characteristics of the fossils and sediment grains will allow me to interpret the relationship between environmental conditions and animal diversity/microbial mat growth among the four microbialite units. My data will help uncover small and large scale changes over time in both the community of multicellular organisms and the microbialites that developed during the deposition of the Notch Peak Formation.

Kirtee Ramo

Advisor: Selby Hearth

Addressing the discontinuities in the geologic time of the Jezero Crater

In February 2021, NASA landed the much-awaited Perseverance rover at Jezero Crater on Mars. It is thought that the crater was an ancient lake and, therefore, it has the potential to give information about possible life on the planet. In order to learn about the geologic history of the Jezero Crater, I’ll be working with Dr. Selby Hearth this summer to go through the available literature about the crater and find discontinuities in the geologic timeline.  Then, we will design and execute a research project to address this gap. To analyze the surface of the crater, we are planning to use publicly released data from the Mars Reconnaissance Orbiter and the Perseverance Mars Rover. Additionally, I am planning for this project to lead into my senior capstone for my major in geology.

Zoe Shinefield

Advisor: Don Barber

The Impact of Land-Use Patterns on Carbon Sequestration in North Carolina Salt Marshes

Salt marsh ecosystems help mitigate emission-driven climate change by absorbing large amounts of carbon dioxide from the atmosphere and sequestering it in coastal sediments. Rates of carbon uptake can be altered by land-use patterns in and around ecosystems. Carteret County, North Carolina contains a range of estuarine, intertidal and upland environments, including carbon-sequestering wetlands, active agricultural land, and agricultural land that has been recently restored to wetlands. This project uses sediment core analyses to examine how sedimentation rates and plant community compositions over the past 150 have been impacted by adjacent upland land-use patterns in coastal North Carolina. Sediment core analyses of carbon density and isotopic composition of sediments are indicators of carbon storage and plant community composition, respectively. When compared with recorded changes in land-use over time, sediment core analyses can be used to reconstruct a history of carbon sequestration. Preliminary studies suggest that less belowground carbon storage occurs in marshes that are exposed to agricultural runoff than in undisturbed marshes. I hypothesize that there is a significant difference in carbon storage between marshes that are adjacent to upland agricultural areas and those that are not.

Understanding the past and present conditions of these wetland sites has important implications for both coastal management and the broader field of climate change research. The data compiled in this research will contribute to broader efforts within the scientific community to compile and share coastal wetland data. Human land-use patterns combined with altered precipitation and accelerated sea-level rise due to climate change are likely to alter carbon sequestration rates in coastal wetlands. Understanding these relationships will inform adaptation and management efforts to maximize carbon sequestration while maintaining these important ecosystems.

Allison Velasquez

Advisor: Arlo Weil

Exploring Laramide Deformation in the Four Corners Region

The Rocky Mountains of western North America is a large-scale tectonic system that has been deformed into various ranges that extend from arctic Canada to Mexico. In the western region of this system is the Laramide belt, which is restricted to the area from central Montana to New Mexico. The Laramide belt is unusual compared to other known mountain systems in that its main ranges have odd orientations and its location is far inland relative to the ancient plate boundary. These atypical characteristics have inspired many questions regarding how and why these mountains formed. There have been several hypotheses over the past century that have been proposed to explain the phenomenon of the Laramide Orogeny. Presently, the most accepted model is that the main tectonic driver for the Laramide was flat-slab subduction. However, identifying a mechanism of the Laramide does not provide an answers as to why individual Laramide mountain ranges have the orientation they do, and why the Laramide does not appear similar to other known and studied mountain ranges.

In an effort to answer these questions, I will be working along side Dr. Weil to gather and collect field data from the four corners region and parts of southern Montana. The goal is to search and identify patterns of deformation, specifically the orientations of shortening directions, found in Laramide ranges to test hypotheses of the region’s tectonic evolution. We will collect core samples to measure the anisotropy of magnetic susceptibility and measure mesoscopic-scale structures like minor faults, stylolites, fractures etc., in order to estimate paleo-shortening directions. Ultimately, these data will allow us to further study Laramide deformation as well as help us to better understand the mechanisms behind their present structures.

Riley Zheng

Advisor: Pedro Marenco

Microbialites are rocks produced through the activities of ancient microbial communities, whose buildups are sometimes large enough to be classified as reefs. They are distinguished by their round shapes and the specific lamination patterns. Microbialites are rare today, but were much more common in the oceans for the ~3 billion years before the advent of abundant animal life. It is possible that some combination of animal grazing activity and changing environmental conditions led to the pronounced decrease in microbialite abundance through time. Studying the geochemistry of microbialites can help us understand the environmental conditions that favor their formation.

My project is mainly based on two sets of microbialite samples found from different formations separated by about 250 million years. One set of samples is from the Lower Triassic Virgin Limestone Formation of Nevada (~250 Ma). These rock samples have clear laminations alternating between dark grey and light brown. My previous stable isotopic results show a relatively large difference in the carbon isotopic composition of dark versus light laminations in which the brown layer is about 1.6 ‰ lighter than the grey layer on average. X-Ray Diffractometer and petrographic analyses reveals that the light brown laminations contain more quartz and exhibit increased porosity than the darker laminations.  These mineralogical and geochemical differences likely represent fluctuating environmental conditions that affected microbial mat growth.

The other set of samples was collected this summer from the Notch Peak Formation in Utah. They are Late Cambrian (~500 Ma) microbialite samples which likely represent different environmental conditions than those of the Early Triassic Period. The Notch Peak microbialites exhibit similar laminated cross sections of the microbial mats with alternating colors. We have collected both float and in-situ microbialite samples from different stratigraphic horizons across the formation for detailed geochemical analysis. For my summer science research project, I will measure carbon isotopic and elemental data from these Late Cambrian microbialites to compare with those from the Lower Triassic. Comparison of the data collected from both sets of microbialites will help reveal commonalities in the environmental conditions required for the formation of microbialites.

América Nájera

Advisor: Leslie Cheng

Valuation of Options

Every day the stock market opens, and options are bought and sold. An option is the right but not the obligation to buy or sell an asset. Options are categorized as vanilla or exotic. Vanilla options include the European and American call and put options, while exotic options include barrier options (also called “knock-out'” or “knock-in” options), lookback options, and Asian options.  Our research will focus on the valuation of these options in the Generalized Binomial Model and in the Black-Scholes Model.

Veronica Wang

Advisor: Leslie Cheng

Mathematics of Hedging

We shall investigate the mathematics of hedging. Hedging is a strategy that tries to minimize risk. Investors will use hedging to reduce and control risk, but in the meantime, investors will lose some potential gains. We shall look at hedging in various mathematical models including the Binomial Model, Generalized Binomial Model, and Black-Scholes Model.

Ellie Hughes and Catie Robinson

Advisor: Michael Schulz

Equivalence of the WKB and instanton semiclassical approximations

The Wentzel–Kramers–Brillouin (WKB) method can be used to approximately solve the Schrödinger equation and find allowed energies for a given potential. Similarly, instanton methods can be used to compute energy splittings in multi-well potentials due to quantum tunneling. The WKB method and the instanton method, while unrelated, yield the same results. However, this equivalence is not obvious due to the differences in the technical details of each method. The goal of this project is to demonstrate that these two methods are indeed equivalent to the same order in ħ for a specific potential where both methods are applicable, namely a double well potential consisting of two harmonic oscillators spliced together. Showing the equivalence between the WKB approximation and the instanton method for this potential will impact our understanding of the accuracy of the two approximations, which may provide new insight into the behavior of particles in different potentials.

Queenie Jiang

Advisor: Michael Noel

We will use optics and spectroscopy to cool and trap rubidium 85 and 87 atoms. Our optics consist of mirrors, lasers, glass or plastic, wave plates, modulators, and lenses. We will then excite these atoms to Rydberg states, which have high quantum numbers (n~30-40) and are weakly bound, causing these atoms to have exaggerated properties. The electric field we apply also provokes the Stark effect, splitting the atoms into several different energy levels. Pairs of these atoms form dipoles as each atom has polarity due to their valence electrons being far from the nucleus. We will then examine the dipole-dipole interactions caused.

Lily Li, Rebecca Long and Genevieve Love

Advisor: David Schaffner

Glow Discharge Model:
The Glow Discharge model is a simplified demonstration of the �������� Experiment (BMX) which enables close observations and could be used in further undergraduate lab teachings. Through a glass chamber, the glow from a gas can be observed between the charged plates which indicates the successful creation of plasma. This experiment gives a preview of the method BMX uses to create plasma which is using a high enough electric potential to break down gas into plasma. There are characteristics of the plasma through four variables ― potential difference of the power source, distance between the electrodes (the two charged plates in this case), gas type, and the pressure of the chamber gas which is associated with the density of the molecules.

Probe Calibration for BMX:
The BMX uses small probes inserted into the main chamber to measure the magnetic field as plasma travels past them. At high enough frequencies, the probes’ induction becomes significant enough to alter the recorded data. As such we must calibrate the probes beforehand by placing them in a known constant magnetic field that oscillates in the same range of frequencies that will be present in the actual experiment so that we can calculate the probes’ error.

Catherine Opsahl

Advisor: Michael Noel

We will use optics and spectroscopy to cool and trap rubidium 85 and 87 atoms. Our optics consist of mirrors, lasers, glass or plastic, wave plates, modulators, and lenses. We will then excite these atoms to Rydberg states, which have high quantum numbers (n~30-40) and are weakly bound, causing these atoms to have exaggerated properties. The electric field we apply also provokes the Stark effect, splitting the atoms into several different energy levels. Pairs of these atoms form dipoles as each atom has polarity due to their valence electrons being far from the nucleus. We will then examine the dipole-dipole interactions caused.

Della Guo

Advisor: Heejung Park

The Association Between Peer Relationship and Psychological Adjustment Among Multicultural Adolescents in South Korea

Multicultural families, in which at least one parent is an immigrant (most commonly mother), are a minority group in South Korea that experiences high rates of psychological distress (Chung & Yoo, 2013). Some research has shown that these families experience problems such as paternal alcohol abuse (J. Lee, Lee, & Park, 2016) and acculturation stress experienced by immigrant mothers and their children (Cho, 2017; Lee & Park, 2018). Nonetheless, little is known about the nature and role of peers in the lives of multicultural adolescents when in fact, these adolescents may rely more on their peers due to insufficient parental support. Furthermore, peers can be especially influential for adolescents in Asian countries such as South Korea where adolescents commonly utilize their time after school to participate in peer-centered extracurricular activities. Thus, my project will investigate the association between peer relationships and psychological adjustments among adolescents in South Korea by utilizing data from 1,600 monocultural (n = 800) and multicultural (n = 800) adolescents in South Korea. I will examine both ingroup relationships (within multicultural/monocultural adolescents) and outgroup relationships (multicultural adolescents' relationships with monocultural adolescents and vice-versa). I predict that monocultural adolescents will demonstrate better school adjustment compared to multicultural adolescents, and this association will be partly explained by acculturation stress. Furthermore, I hypothesize that there will be a positive association between outgroup peer relationships and psychological adjustments for multicultural adolescents as outgroup peer relationships can serve as an indicator for acculturation for multicultural adolescents. The results can provide meaningful implications for helping multicultural adolescents adjust to their life in contemporary Korea.

Keywords: multicultural family, multicultural adolescent, peer relationship, psychological adjustment

References

Cho, Y. (2017). Externalizing Behaviors in Multicultural Children of Immigrant Mothers: A Mediation Model. Journal of Family Issues, 38(7), 904–920. https://doi.org/10.1177/0192513X15592028

Chung, G. H., & Yoo, J. P. (2013). Using the Multicultural Family Support Centers and Adjustment Among Interethnic and Interracial Families in South Korea. Family Relations, 62(1), 241–253. https://doi.org/10.1111/j.1741-3729.2012.00754.x

Lee, J., Lee, R., & Park, M. (2016). Fathers’ alcohol use and spousal abuse and mothers’ child abuse in multicultural families in South Korea: The mediating role of acculturation and parenting stress. Children and Youth Services Review, 63, 28–35. https://doi.org/10.1016/j.childyouth.2016.02.003

Lee, Y., & Park, S. (2018). The mental health of married immigrant women in South Korea and its risk and protective factors: A literature review. International Journal of Social Psychiatry, 64(1), 80–91. https://doi.org/10.1177/0020764017744581

Annie Hawks

Advisor: Laura Grafe

Stress, Sleep, and the Menstrual Cycle

Stress-related psychiatric disorders such as Major Depressive Disorder (MDD) and Post Traumatic Stress Disorder (PTSD) are twice as prevalent in women than in men. One possible factor that may be associated with this difference is sex hormones, such as estrogen and progesterone. Research has shown that the disparity between men and women in the incidence rate of stress-related psychiatric disorders is associated with reproductive transitions. Specifically, these disparities often emerge with the onset of puberty and begin to fade with menopause. Sleep disturbances are a key phenotype in stress-related psychiatric disorders, and thus, sleep is an important variable to examine throughout hormone fluctuation. Another factor in the vulnerability to stress is the coping strategy adopted. In different individuals, or under different conditions, either adaptive or maladaptive coping strategies are used in response to stress. This project aims to understand how sex hormones and coping strategy may influence stress-related psychiatric disorders by studying the associations between the menstrual cycle, stress, coping strategies, and sleep. Our project will use Fitbit devices to track the menstrual cycle, stress levels, and sleep stages in female participants. We will also use a survey to investigate how coping strategies influence stress and sleep levels. In this study, we are prioritizing women’s health by conducting a study specifically in females to better understand disorders more common in women; the ultimate goal is to develop more effective treatments for stress-related disorders in women.

Sarah Luo

Advisor: Ariana Orvell

Outsourcing Reappraisal as an Emotion Regulation Strategy

Emotion regulation, the ability to exert control over one’s emotional state, is a skill critical to one’s interpersonal relationships and mental well-being. People use a variety of strategies to regulate their negative emotions (e.g., exercising, meditation, writing in a journal, etc.). Two widely studied strategies are distraction, which involves thinking about things unrelated to the emotional stressor, and reappraisal, which involves changing the way one thinks about an emotional stressor to reduce its emotional impact (Gross, 2015). These two strategies both have pros and cons: distraction is relatively easy to implement but is less helpful over time (Kross & Ayduk, 2008); on the contrary, reappraisal requires more cognitive resources but can help individuals adapt to the stressors over the long term. Based on this cost-benefit trade-off, Sheppes and his colleagues (2012) established a framework, supported by empirical evidence, that suggests while people prefer to reappraise under low emotional intensity conditions, they are more likely to distract when the emotional intensity is high.

However, in real life, the resources for emotion regulation are not limited to the individuals themselves: people can also turn to others, in other words, ‘outsource’, to help them reappraise. Unlike intrapersonal reappraisal, outsourcing reappraisal shares the workload of reinterpretation with another person. As a result, it’s potentially easy to implement, helping people regulate their thoughts, feelings, and behaviors in a relatively effortless way (Orvell, 2019). This raises the question of whether people will prefer outsourcing reappraisal over intrapersonal reappraisal and distraction because it’s not cognitively challenging.

Under the supervision of Dr. Orvell, the study I will be working on this summer will test the hypothesis that individuals prefer to outsource even when their emotional intensity is high because it’s both effortless and beneficial to their long-term adjustment. Specifically, we’ll use an experimental design to examine which strategy participants prefer among distraction, reappraisal, and outsourcing reappraisal when the emotional intensity of the stressor is high vs. low. The results of this study will help add to a growing body of work on how and when people choose different emotion regulation strategies, providing insights into which regulatory strategy is most appropriate in different situations.

Sophia Ou

Advisor: Anjali Thapar

Examining effects of aging on memory performance using Event-Related Potentials

Research on age-related changes in episodic memory has indicated that older adults, relative to younger adults, are less capable of encoding and retrieving information. Electroencephalography (EEG) and event-related potentials (ERPs) are well established methods used to associate neural activity in the brain with -behavioral differences in memory performance. In Professor Thapar’s lab, EEG data is collected from younger and older adult participants during the associative recognition memory task. My summer research project aims to examine the age-related differences in memory performance by analyzing the EEG data collected from the participants. The EEG data shows the neural activities associated with specific memory performance, such as encoding and retrieval. By manually filtering the EEG data and running the Independent Component Analysis, we could filter out irrelevant noises and artifacts such as eye and muscle movement and plot out the ERPs. ERPs are usually analyzed in the time domain, but we will use the time-frequency analysis which allows us to investigate both the frequency of an event-related oscillation and its evolution over time. The use time-frequency analysis of ERPs allows us to tie what we identify as behavioral differences to the actual brain activities. The results will provide a better understanding of episodic memory and how it changes with adult aging.

Karen Prangan

Advisor: Heejung Park

A Reckoning with Asian American Identity: Ethnicity and Panethnicity During the COVID-19 Pandemic

The racialization of the COVID-19 pandemic has brought about alarming rates of anti-Asian hate crimes and xenophobic rhetoric, a 147% increase in the last year (Jeung et al., 2021). Given that such hostile racial climates threaten the identity development and well-being of Asian Americans (Cheng, 2020; Iwamoto & Liu, 2010), my project examines racial and ethnic identity in times of COVID-19. I predict the rise of collective, panethnic Asian American identity due to increased solidarity and coalition-building between different Asian ethnic groups. Additionally, I posit that ethnic identity among Asian American emerging adults has also deepened, as a result of growing awareness of the heterogeneity of Asian American experiences. Furthermore, I aim to explore within-group differences (e.g., generation, ethnicity) in the racial and ethnic identity development. Using the qualitative approach of conducting semi-structured, narrative-based interviews, and thematic analysis (Jovchelovitch & Bauer, 2000; Braun & Clarke, 2006), I will examine the nuances and complexity of identity development in Asian American emerging adults. My study will expand the current knowledge on the identities of Asian American ethnic minorities, heighten awareness of community issues during the pandemic, and offer implications for practical tools that help promote healthy development and healing of a minoritized population.

Keywords: COVID-19, Asian American, Racial Discrimination, Identity, Emerging Adults

References

Braun, V., & Clarke, V. (2006). Using thematic analysis in psychology. Qualitative Research in Psychology, 3(2), 77–101. https://psycnet-apaorg.proxy.brynmawr.edu/doi/10.1191/    1478088706qp063oa

Cheng, H. L. (2020). Xenophobia and Racism Against Asian Americans During the COVID-19 Pandemic: Mental Health Implications. Journal of Interdisciplinary Perspectives and Scholarship, 3(1), 3. https://repository.usfca.edu/jips/vol3/iss1/3

Iwamoto, D. K., & Liu, W. M. (2010). The impact of racial identity, ethnic identity, Asian values, and race-related stress on Asian Americans and Asian international college students’ psychological well-being. Journal of Counseling Psychology, 57(1), 7991. https://doi-org.proxy.brynmawr.edu/10.1037/a0017393

Isabella Ravaglia

Advisor: Laura Grafe

Differences in the Spectral Power Density of Sleep EEG Between Male and Female Rats After Stress  

Stress-related disorders such as Major Depressive Disorder (MDD) and Post Traumatic Stress Disorder (PTSD) are more prevalent women, and disruptions in sleep quality are a common feature associated with these disorders. Specifically, insomnia and sleep fragmentation are common in both MDD and PTSD. Previous rodent research in our lab found persistent decreases in Slow Wave Sleep (SWS) and REM sleep in female rats after repeated stress. This project will expand on this research by more closely examining the electroencephalogram (EEG) from these rodents, which allows for characterization of different stages of sleep. Particularly, we will conduct spectral analysis of the frequency bands that make up the EEG signal (delta, theta, alpha, eta, and beta), which will provide insight into how changes in the power of different frequency bands impact the overall EEG signal and sleep architecture. We will compare Power Spectral Density (PSD) between males and females measured during different vigilance states before, during, and after repeated stress. While previous studies have found changes in frequency band power during REM after prolonged stress in rodents, these studies were conducted in males only. Thus, this analysis will provide novel insight to how PSD during sleep differs between the sexes during prolonged stress. This research will also advance our understanding of how neuronal oscillations contribute to sleep disruptions observed in stress related psychiatric disorders.

Rita Sabri

Advisor: Anjali Thapar

The diffusion model is a stochastic model of the cognitive processes involved in simple two-choice decisions (Ratcliff, 1978). A handful of psychologists have applied the diffusion model to study task performance associating with aging, depression and ADHD.  Although the diffusion model has been successfully applied to study both human and animal behavior, a challenge for broader adoption of the model in Psychology is that it requires advanced applied mathematical knowledge beyond that of the typical statistical training obtained in graduate programs. Over the past decade, four different “user-friendly” variants of the diffusion model have been developed for researchers hoping to use the diffusion model to fit experimental data.  My first goal for this summer is to familiarize myself with the diffusion model and with each of the four variants of the diffusion model.  Working with the four versions of the diffusion model, I will understand the similarities and differences across the four models with the goal of being able to identify the circumstances and how they differ from each other.  During my journey of understanding how those 4 models work, I will systematically test each version with simulated datasets. Finally, I will choose the best-fitting versions of the diffusion model and systematically test these models by fitting them fit to data from memory experiments collected in the Cognition and Aging lab.  

Mahek Nirav Shah

Advisor: Marc Schulz

The role of childhood family environment in shaping relationship orientation in adulthood

Individuals inhabit many relationships across their lifetime beginning with their connections to parents and siblings and extending to friends and partners. Individuals’ understanding and involvement in relationships differ in important ways. This summer research project looks to examine the role of childhood family environment in shaping the ways in which people approach their relationships later in life. Building on existing theory on attachment and relationship structures (Brennan, Clark, & Shaver, 1998) and on relationship quality (Lawrence et al., 2011), the goal is to build a model of relationship orientations that will identify and differentiate key ways in which people approach their relationships. Relationship orientation captures relationship behaviors, that range from spending time with people to allowing emotional dependence on others, through the lens of willingness, worthiness, ease, and pleasure. Data will be drawn from an 85-year-old study, the Harvard Study of Adult Development which has captured the entire lives of 268 men who went to Harvard University in the early 1940s. After developing the conceptual model of relationship orientation, a latent profile analytic approach will be used to identify groups of people who have different relationship orientations. The warmth and consistency of childhood family environment will be examined as predictors of these relationship orientation profiles. This work will enhance our understanding of the relational consequences of children’s family environment across the lifespan. 

References

Brennan, K. A., Clark, C. L., & Shaver, P. R. (1998). Self-report measurement of adult attachment: An integrative overview. In J. A. Simpson & W. S. Rholes (Eds.), Attachment theory and close relationships (p. 46–76). The Guilford Press.

Lawrence, E., Barry, R. A., Brock, R. L., Bunde, M., Langer, A., Ro, E., Fazio, E., Mulryan, L., Hunt, S., Madsen, L., & Dzankovic, S. (2011). The Relationship Quality Interview: evidence of reliability, convergent and divergent validity, and incremental utility. Psychological assessment, 23(1), 44–63. https://doi.org/10.1037/a0021096

Victoria Wei

Advisor: Ariana Orvell

“That moment when:” How context shapes people’s engagement with positive experiences

Research shows that subtle shifts in language can not only reveal how people are thinking but can also affect how people interpret a message. An often-overlooked linguistic tool that Professor Orvell’s lab has been studying is the use of generic-you (i.e., “you” that refers to people in general, rather than to a specific person, e.g., “What kills you make you stronger”). In previous work, Professor Orvell and her colleagues found that people use generic-you to make meaning out of negative experiences because it minimizes the focus on the self, allowing people to distance themselves (i.e., self-distance) from their own negative experiences and see it as part of a shared and broader phenomenon. It makes sense to self-distance from negative experiences, but might there be times when people would want to self-distance from positive experiences, which people are typically motivated to self-immerse in? Professor Orvell and colleagues reasoned that if people are sharing about a positive experience publicly (e.g. on social media), they may be motivated to de-emphasize the focus on the self – by using generic-you – to make sharing more comfortable or to project humbler image. For example, a person writing on Facebook about earning a top grade may say “That moment when you feel so accomplished,” whereas they might be more likely to say “I felt so accomplished” if writing privately, in a diary. In the present study, we are interested in how people react to social media posts with generic-you (vs. “I”) in them. We have two competing hypotheses: On one hand, we hypothesize that the writer of posts written with generic-you will be liked more, because they may seem humbler and the events sound more relatable. Alternatively, the writer of the post may be liked less because the use of generic-you may be perceived as inauthentic. In this research, we hope to shed light on how this subtle linguistic device can meaningfully influence interpersonal processes related to interpersonal connection and person perception.