Presentation Days 2024 Abstracts

Biology

Cevi Bainton

Advisors: Matina Donaldson-Matasci, associate professor of biology; Cathy McFadden, Vivian and D. Kenneth Baker Professor in the Life Sciences

Spatially Modeling Gene Enrichments from Cell Morphology in Breast Cancer

Breast cancer is a highly damaging disease that is hard to predict. One can better understand cancer development by considering the genetic heterogeneity of tumor cells, but the new techniques that make this possible are expensive and hard to scale. This thesis predicts genetic status in space within a tumor based on cell images from a spatial transcriptomics data set in breast cancer.

Clements Evans

Advisors: Jae Hur, associate professor of biology; Danae Schultz, associate professor of biology

SPG7, Protein Degradation and Longevity in Drosophila

This thesis is focused on the gene SPG7 and its relation to protein degradation and aging. SPG7 codes for paraplegin, a mitochondrial protease. Previous work in the Hur lab marked it as a gene of interest for longevity studies, and a study by Pareek et al found that knocking out SPG7 negatively impacts the longevity, health and stress resistance of flies. We will over-express SPG7 in drosophila and measure the effects on protein degradation and lifespan. This thesis will be the first overexpression study of SPG7 with a focus on longevity. We will address whether an overexpression of SPG7 leads to improved health, stress resistance and longevity in flies.

Evan Kim

Advisors: Danae Schulz, associate professor of biology; Matina Donadlson-Matasci, associate professor of biology

Sufficiency of Bromodomain Protein 3 in Initiating Transcription of Procyclin Genes During Differentiation of African Trypanosomes From the Bloodstream to the Procyclic Form

Trypanosoma brucei causes fatal diseases such as Human African Trypanosomiasis. The parasite cycles between a bloodstream form in mammals and a procyclic form in its fly host vector. The procyclic form, characterized by invariant procyclin, is expressed via transcription of EP genes. However, the mechanism by which EP transcription is activated during differentiation is not well understood. The Schulz Lab previously showed de novo occupancy of Bdf3 at EP regions as the parasite differentiates from the bloodstream to the procyclic form. We aim to show that Bdf3 is sufficient for activating transcription of EP by utilizing a CRISPR system to artificially tether Bdf3 to the EPI locus in bloodstream parasites in order to give insight to common transcriptional controls for early eukaryotes.

Chadinthon Minnie Kittivorawong

Advisor: Jae Hur, associate professor of biology

Mitochondrial Activity of Mild ClpXP Overexpression Drosophila Melanogaster

The cellular metabolism results in the production of reactive oxygen species, which could damage proteins involved in cell activities. As a part of the protein homeostasis (proteostasis) mechanism, protease will destroy the damaged protein and balance the ratio of damaged and working proteins. In 2019, Goldman found that with low levels of ClpXP overexpression, female D. melanogaster life span increases. Over the past summer, I helped show that overexpressing the ClpXP at high levels results in higher protein degradation and lower complex II activity. Therefore, this thesis aims to study the mitochondrial protein degradation and mitochondrial complex activity by applying the assay protocols I helped optimize over the summer to the mildly ClpXP overexpression flies that were shown to have extended longevity in Goldman’s study.

Kenneth Mitchell

Advisor: Matina Donaldson-Matasci, associate professor of biology

Deep Learning Pipeline for Extracting Tree Flowering Phenology From NEON Remote Sensing Imagery

Phenological mismatches driven by anthropogenic climate change pose threats to mutualistic species, such as pollinators and pollinator-dependent plants. Intraspecific phenological variation could mitigate these risks, yet its causes are not well understood—partially due to a lack of phenological data on a fine spatial scale, which is labor-intensive to produce. Remote sensing imagery, such as those generated by the National Ecological Observatory Network (NEON), presents an untapped potential for vast amounts of phenological data. Leveraging advances in computer vision and remote sensing technologies, I developed a novel pipeline to extract individual-level tree flowering phenology data at a large scale. The pipeline incorporates existing tree detection algorithms as well as a novel architecture for an attention-aided convolutional neural network for species and phenophase classification from hyperspectral imagery.

Lucia Morales

Advisors: Steven Santana, Iris and Howard Critchell Assistant Professor of Engineering; Steve Adolph, Stuart Mudd Professor of Biology

Interrogating the Relationship Between Extracellular Vesicle miRNA Contents and Matrix Stiffness

Extracellular vesicles (EVs) are membrane enclosed particles excreted by the cell in response to changes in cell microenvironment, such as matrix stiffness and peptide concentration. While we know that these changes are prompting EV secretion, we do not know the exact signaling pathways that lead to the secretions. In this project, I am investigating the relationship between EV miRNA contents and hydrogel matrix stiffness at a constant peptide concentration. Using next generation sequencing to find specific miRNAs contained in the EVs, we can then use gene ontology and literature reviews to identify potential pathways that are being activated in EV secretion. Additionally, we will be using nanoparticle tracking analysis and western blotting to verify the existence of EVs in our samples. 

Paul Oh

Advisors: Jae Hur, associate professor of biology; Eliot Bush, professor of biology

Effects of Independent ClpX and ClpP Overexpression on Proteolysis, Mitochondrial Function and Health in Drosophila Melanogaster

Protein degradation in the mitochondria is thought to regulate aging. ClpXP is a mitochondrial protease complex consisting of ClpX and ClpP subunits and degrades misfolded proteins generated from metabolic pathways. Past studies from the Hur Lab show significant effects of simultaneously overexpressing ClpX and ClpP on Drosophila melanogaster’s ability to degrade substrates and to regulate mitochondrial activities. However, any complex-independent activities of ClpX and ClpP that particularly pertain to aging have not been studied in Drosophila melanogaster. Therefore, my research addresses these limitations by characterizing the effects of independent overexpression of ClpX and ClpP in D. melanogaster on proteolysis, mitochondrial activities, and health.

Sydney Porto

Advisor: Danae Schulz, associate professor of biology

Generating a Modified T. Brucei Cell Line for Investigating the Role of Acetylation in Facilitating an Increase in BDF3 Occupancy at the EP1 Locus During Differentiation

Trypanosoma brucei, the causative agent of sleeping sickness, exists in bloodstream form in the mammalian bloodstream and procyclic form in the body of the tsetse fly. When the parasite differentiates into procyclic form, it begins expressing an invariant surface protein encoded by EP1. The Schulz Lab has previously shown that a chromatin-interacting protein, BDF3, is not found at the EP1 promoter in bloodstream parasites, but the occupancy at this locus increases during differentiation. This suggests that BDF3 may contribute to the increase in EP1 transcription. However, we do not know what facilitates the increase in occupancy by BDF3 at this locus. Therefore, I generated a cell line with a histone acetyltransferase 2 (HAT2) RNAi knockdown and HA-tagged BDF3 to be used in future experiments to test if acetylation at the EP1 promoter facilitates the increase in BDF3 occupancy. 

Phia Riberio

Advisors: Steven Santana, Iris and Howard Critchell Assistant Professor of Engineering; Steve Adolph, Stuart Mudd Professor of Biology

Extracellular Vesicle Biogenesis and its Relation to Cell Matrix Binding

There are several types of cell communication, often involving secreting biomolecules to interact with other cells. One type of cell communication involves secreting extracellular vesicles (membrane-bound vesicles filled with biomolecules) that are taken up by other cells in different parts of the human body. Little is known about the biogenesis of extracellular vesicles (EVs). Cells are known to be affected by their binding to the cell-matrix. They are bound via clusters of binding to peptides embedded in extracellular matrix proteins. I am investigating the effect of modulating peptide concentration in the cell matrix on EV biogenesis.

Karen Snyder

Advisors: Karl Haushalter, Seeley W. Mudd Professor of Chemistry and Biology; Anna Ahn, professor of biology

p53-OGG1 Interaction for Survivin Transcriptional Repression 

This project tests the DNA binding proteins p53, a transcription factor and tumor suppressor, and OGG1, a glycosylase and DNA repair protein, for cooperative or competitive binding to the enhancer region of the gene survivin. Survivin is an inhibitor of apoptosis, an important pathway for preventing cancers. The enhancer region of the survivin gene contains a p53 binding site that prevents transcription of survivin. This project uses competitive electrophoretic mobility shift assay to test the binding of p53 and OGG1 to the enhancer region of survivin in vitro. Three different variations of the survivin enhancer region are used, one with no modifications and two with an abasic site replacing one of the guanine bases.

Matea Zelich

Advisors: Karl Haushalter, Seeley W. Mudd Professor of Chemistry and Biology; Cathy McFadden, Vivian and D. Kenneth Baker Professor in the Life Sciences

Adapting a Protocol for Observing Protein-DNA Interactions to Study the Epigenetic Role of DNA Base Modifications

Epigenetics refers to changes in DNA which regulate gene expression but are not a change in its sequence. This can result in the winding and unwinding of DNA around histone proteins, affecting the accessibility of DNA to transcription factors, proteins which regulate transcription. DNA base modifications have been known to be a potentially mutagenic result of oxidative stress; however, recently base modifications have also been shown to have epigenetic roles. This thesis aims to study the DNA-protein interaction of base modification deoxyuracil (dU) and its repair enzyme SMUG1 with well-known transcription factor p53. By observing the impact of dU and SMUG1 on p53 DNA binding, this thesis aims to learn whether the presence of dU and its repair machinery can lead to transcriptional changes.

Chemistry

James Barrett

Advisor: Sarah Kavassalis, assistant professor of chemistry and climate   

Forest Fires in Flux: Analyzing Trends and Influences on Oceanic Temperate Forests in a Changing Climate

Climate change has significantly transformed fire regimes. Using satellite data and climate models, this thesis identifies fire incidence and severity trends in oceanic temperate forests—biomes once shielded from climate change due to their coastal location. The study considers climatic and human influences on forest fires. Data visualization, statistical analysis, and policy quantification clarify the relationship between climate extremes, human activity and fire. Understanding these interactions enhances predictions of future fire activity and air quality impacts, informing forest management policies to safeguard these crucial ecosystems.

Jesse Chen

Advisors: Karl Haushalter, Seeley W. Mudd Professor of Chemistry and Biology; Mark Ilton

Elucidating the Competitive Dynamics of p53 and AP Endonuclease 1 on Abasic DNA Promoter

The tumor suppressor p53 is a multifunctional protein that plays essential roles in regulating cell-cycle progression and DNA repair. Thus, p53 plays essential roles in regulating cell-cycle progression and repair. While the upregulation of p53 drives apoptosis or programmed cell death, a competing path is to repair damaged DNA sites with the BER pathway with AP Endonuclease 1 (APE1). Since APE1 also has functions of transcriptional regulation and controlling responses to oxidative stress, cells “choose” between pathways of death (p53) or repair (APE1) depending on the severity and location of DNA damage. This project shows experimentally and computationally how p53 may compete or cooperate with APE1 for damaged DNA regions depending on the order at which they arrive at DNA damage.

Helen Chen

Advisor: Sarah Kavassalis, assistant professor of chemistry and climate

Preparatory Work for Long-term Greenhouse Gas Flux Measurements at the Robert J. Bernard Field Station, Claremont, California

California’s intensifying fire seasons, worsening drought, and swift vehicle emissions shifts underscore an urgent need for improved atmospheric data and models. This thesis introduces a new observational site within the AmeriFlux network, located at the Robert J. Bernard Field Station, within the endangered California coastal sage scrub. In this presentation, I describe utilizing wind direction and HYSPLIT back-trajectories to establish this flux tower, sharing preliminary data from our setup calibration. This endeavor aids the development of advanced atmospheric chemistry models and refines climate predictions. Furthermore, it enriches AmeriFlux’s data, contributing to global CO₂ budget estimation and future atmospheric CO₂ projections.

Natalie Couch

Advisor: Alicia Hernandez-Castillo, assistant professor of chemistry

Rotational Spectroscopy of Water-Ketone Clusters

Gas phase microwave spectroscopy is a powerful tool for investigating intermolecular interactions such as hydrogen bonding. These weak interactions are difficult to investigate in solution, where they are constantly broken and reformed. In the ultrahigh vacuum inside our microwave spectrometer, clusters of molecules connected with hydrogen bonds exist long enough for us to probe their rotational transitions and giving precise information on the structure of the cluster. I specifically looked at interactions of water and 2-methylcyclopentanone, which can act as a hydrogen bond acceptor. I created a system for mixing the two chemicals before as they enter the instrument and took a spectrum of the mixture.

Jovin Ho

Advisor: Hal Van Ryswyk, John Stauffer Professor of Chemistry

Orthogonal Chemistry in Third-Gen Photovoltaics

Perovskite-clad lead sulfide quantum dots solar cells (PQDs) are third-generation photovoltaics offering improved efficiencies, cost effectiveness, and ease of scalability over previous generations. The Van Ryswyk lab constructs PQDs by suspending photoactive quantum dots in a 2,6-difluoropyridine (DFP) solvent and depositing the layer atop a zinc oxide (ZnO) electron transport layer via blade coating. The use of DFP is a new development within the field. There is a concern that DFP may erode the ZnO as the orthogonal interactions between layers have not been established. Changes in surface morphology were investigated by optical and atomic force microscopies, showing that DFP had no measurable impact on the ZnO layer. Given these findings, complete PQDs were constructed and evaluated.

Aech Loar

Advisor: Spencer Brucks, assistant professor of chemistry

Controlling Plastic Properties Through Stereochemistry

As global plastic production continues to increase, plastic waste management is failing to keep up. Current infrastructure best supports mechanical recycling, but only plastic types 1 and 2 are typically curbside recyclable. This project aims to improve the applicability of mechanical recycling across different plastics by studying the relationship between backbone stereochemistry and degradability. I used different catalysts, solvents, and temperatures to create polymers with different structures, then tracked how they changed as they were systematically degraded to compare how these structures affect their degradation.  

Sydney Neibert

Advisor: David Vosburg, professor of chemistry

Mild, Green Acylation of Carbon Nucleophiles Using TCFH–NMI

The combination of the coupling reagent N,N,N’,N’-tetrachloroformamidinium hexaflourophosphate (TCFH) and the nucleophilic base N-methylimidazole (NMI) has recently been shown to be effective for the preparation of amides, esters, and thioesters. We have extended this chemistry to the synthesis of ketones by acylating electron-rich carbon nucleophiles with TCFH–NMI. This greener protocol avoids corrosive acid chlorides and sensitizing coupling reagents such as EDAC, DCC, and HBTU. We have identified optimal reaction conditions, initial scope, and HPLC method conditions thus far such that the scope of the products will be expanded further.

James Nicholson

Advisor: Colm Healy, visiting assistant professor of chemistry    

Incorporating Redox-Active Metal Oxides Into Amorphous MOFs

Metal-organic frameworks (MOFs) are a class of materials composed of metal ions connected by organic linkers. Recent evidence suggests that glass-phase (or amorphous) MOFs can be better redox catalysts than their crystalline counterparts. To create redox-active glass MOFs, we aimed to synthesize glassy ZIF-62 (ZnC6.48H6.24N4) doped with a redox-active molybdenum oxide (K6Mo7O24). We mixed crystalline ZIF-62 with molybdenum oxide and heated the physical mixture above ZIF-62’s melting point. When studied by PXRD, SEM and PLM, the cooled product appeared to be a glassy MOF with unidentified, potentially mixed-metal, crystalline products embedded within the glass. We believe the metal oxide dissolved in the liquid MOF and subsequently re-precipitated as an unidentified crystalline product.

Caetano Pérez-Marchant

Advisors: Spencer Brucks, assistant professor of chemistry; Mark Ilton, assistant professor of phsics

Developing Polynorbornene Bottlebrush Sidechain and Crosslinker Monomers for Stereospecific Polymerization

The overarching goal of my research is to examine how backbone stereochemistry influences the material properties of a bottlebrush gel. We are curious what differences cis (Z) and trans (E) backbone configurations of polynorbornene will have on the macro-properties of a bottlebrush gel containing polyethylene glycol (PEG) sidechains and crosslinkers. My thesis has focused on the synthesis of the necessary polymerizable monomers. Currently I have synthesized norbornene imide sidechain and crosslinker monomers by reacting PEG amine and diamines to a norbornene anhydride derivative. A majority of the work has focused on purifying the monomers and improving the reaction yield. The next step in my this research is to polymerize the monomers using stereospecific catalysts and measuring their Young’s Modulus and elastic efficiency using dynamic mechanical analysis (DMA).

Jocelyn Sabin

Advisor: Adam Johnson, professor of chemistry 

Synthesis of Chiral Titanium Complexes

The Johnson lab has been interested in studying titanium-based catalysis because it has the potential to replace catalysts that rely on more expensive, less abundant metals like ruthenium, rhodium, and palladium. This year we’ve synthesized 8 new titanium complexes using 4 different amino-acid-derived ligands with a ferrocene core, all similar to the one shown in the figure. Due to the structure of the ligands, the products have interesting geometry and chirality.  

Connor Seto

Advisor: Lelia Hawkins, professor of chemistry, Hixon Professor of Climate Studies

Investigating the Relative Performance of PurpleAir and QuantAQ Modulair™-PM Sensors in Claremont, CA, as a Function of Aerosol Properties and Meteorology

Low-cost sensors (LCSs) have been increasing in popularity for measuring air quality with finer spatial and temporal resolutions. LCSs for PM typically rely on calibrated light scattering response and assumptions of particle composition, shape, and size distribution to predict ambient mass concentrations of PM. In this study, we deployed multiple units of two different types of LCS, PurpleAir Flex and QuantAQ Modulair™-PM. We characterized the aerosol population chemically and physically to determine if correlations between the LCSs were attributed to certain aerosol types or meteorological conditions. Our results indicate that ambient relative humidity plays a larger role in agreement between the two sensors than aerosol properties.

Luke Stemple

Advisor: David Vosburg, professor of chemistry

Diversifying a Complex Pyridine Cyclization Cascade

The Reisman group recently reported an elegant reaction cascade in which pyridine and glutaryl chloride combine to give a complex, dearomatized tetracyclic product. This tetracycle possesses the skeletal framework of the medicinally important matrine-class alkaloids. We have developed a greener modification of this cascade and have found that novel tetracyclic products can be formed by varying the starting materials, with varying purities and success rates.

Mathematics

Niles Babin

Advisors: Lisette de Pillis, professor of mathematics and Norman F. Sprague, Jr. Professor of Life Sciences; Kelvin Quiñones-Laracuente, NYU Langone

Information and Neural Mechanisms of Social Learning

The animal brain is capable of performing vast computations at low energy costs, ranging from balancing hormones to encoding spatial information of surrounding environments. A crucial aspect of the brain’s dynamic performance is its capacity to learn, facilitated by the generation, termination, and tuning of connections between neural cells. This thesis investigates the mechanisms by which the mouse brain encodes socially relevant information to learn new maternal processes, specifically pup-retrieval. By modeling the neural activity of the mouse PVN at the single-cell, cell-population, and connectomic (i.e., pairwise connections between neurons) level, this thesis draws insights into the dynamic neural representations the PVN utilizes to encode socially relevant information.

Clay Adams

Advisors: Konrad Aguilar; Alfonso Castro, McAlister Professor of Mathematics

Explorations in Nonstandard Analysis

Nonstandard analysis is a field which introduces rigorous ways to reason about infinite and infinitesimal quantities for the study of calculus. With the ability to study “calculus without limits,” the field is known for more intuitive descriptions of familiar concepts like differentiation and convergence. For instance, to tell if a function converges to a certain point, we just “plug in infinity.” In my project, I dove deep into this field and the formal logic that underpins it, and even produced some nonstandard proofs of familiar theorems from analysis.

Toby Anderson

Advisors: Dagan Karp, professor of mathematics; Siddarth Kannan, UCLA

The Dual Boundary Complex of the Moduli Space of Cyclic Compactifications

Moduli spaces provide a useful method for studying families of mathematical objects. We study certain moduli spaces of algebraic curves, which are generalizations of familiar lines and conics. This presentation focuses on the dual boundary complex of the moduli space of genus-zero cyclic curves. This complex is itself a moduli space of graphs and can be investigated with combinatorial methods. Remarkably, the combinatorics of this complex provides insight into the geometry and topology of the original moduli space. I will present my investigation into two topologically invariant properties of this space: its Euler characteristic and homotopy type.

Jasper Bown

Advisors: Javier González Anaya, visiting assistant professor of mathematics; Patricio Gallardo

Connecting Graphs, Polytopes, and Moduli Spaces

Polytopes play a central role in a connection between moduli spaces and graphs. For my thesis, moduli spaces motivate the study of these connections. In a moduli space, each point corresponds to a geometric object. When geometers study these spaces, they often care about compactifying the space. A technique introduced by Hassett for the moduli space M0,n is to compactify according to a set of weights. For certain toric weights, the resulting space corresponds to a polytope. On the other hand, the notion of a graph associahedron gives a way of constructing a polytope using a graph. Motivated by a result of Jensen, Ranganathan, and Da Rosa which specifies the set of weights and set of graphs which result in the same polytopes, my thesis studies how to extend this result using nestohedron.

Tian Dong

Advisors: Heather Zinn-Brooks, assistant professor of mathematics; Andrew Bernoff professor of mathematics

A Foray into Opinion Dynamics: Exploring Sigmoidal Bounded Confidence Models with Mean Field Methods

Models of opinion dynamics seek to describe how opinions in a group of people change over time, which can yield insight into the mechanisms behind phenomena like polarization and consensus. In these models, mathematicians represent the community as a graph, where nodes represent agents and edges represent possible interactions. Opinion updates are modeled with a system of differential equations (ODEs). Our work focuses on the sigmoidal bounded confidence model (SBCM), where agents update their opinion toward a weighted average of their neighbors’ opinions by weighting similar opinions more heavily. Using tools developed in physics (mean-field theory), we derive a continuity equation from the system of ODEs to further analyze the model’s steady states and compare with numerical simulations.

Kai Rajesh

Advisors: Peter Kagey, visiting assistant professor of mathematics; Arthur Benjamin, Smallwood Family Professor of Mathematics

A Proof of Robert Wilson’s t≠2 Conjecture on Ron Graha’s Sequence

We prove that for every interval (n,m) of positive integers where n and m have the same squarefree part, there exists a subset of the interval whose product also has the same squarefree part. This resolves a 2002 conjecture by Robert Wilson regarding Ron Graham’s sequence, a surprising bijection between the positive integers and the non-primes.

Physics

Svetlana Altshuler

Advisor: Nicholas Breznay, assistant professor of physics  

Investigating Quantum Electrical Properties Through Low-Temperature Characterization

Like the flow of a river, we expect electrical current to flow continuously. However, when some special materials get very cold, this “flow” becomes stepwise, producing quantum electronic effects. Notable quantum effects include superconducting transitions or the quantum Hall effect (QHE). As part of setting up a new low-temperature cryostat, I took electrical measurements of two Nobel Prize-winning materials, yttrium barium copper oxide (YBCO) and graphene. YBCO is a well-studied superconductor with a high critical temperature, and graphene has been shown to exhibit QHE at liquid nitrogen temperatures. I will discuss our latest measurements of the electrical conductivity and magnetotransport properties of both materials and summarize our lab’s new quantum electrical transport capability.

Matthew Chalk

Advisors: Nicholas Breznay, assistant professor of physics ; Joseph Falson, CalTech

Characterizing Even-Order Nonlinear Effects Arising From Symmetry Breaking and Geometrical Phase in Graphene

Graphene’s high electron mobility, mechanical strength, and capacity to host exotic electronic states have attracted wide interest since its isolation in 2004. However, even-order nonlinear effects (for instance, the conversion of light to DC current necessary for a photovoltaic effect) are disallowed by the symmetries of graphene’s crystal structure. Here, we study a novel method of inducing asymmetry in exfoliated graphene using substrate-induced strain. We probe the resulting optical and electrical behavior using low-temperature transport apparatuses set up over the course of this thesis. We will present preliminary measurements of a nonlinear anomalous Hall effect and bulk photovoltaic effect in our devices, as well as several other unconventional effects not seen in pristine graphene.

Audrey Cole

Advisors: Alfredo Gurrola, Vanderbilt University; Francesco Romeo, CERN  

Novel Technique for Low-Mass Type I Heavy Majorana Neutrino Searches

With the absence of new physics in searches at higher masses at the LHC, there is an increased emphasis on investigating lower mass regimes. We propose a new technique specifically designed to explore particles with masses below 200 GeV, particularly those produced in association with a high-pT lepton and exhibiting Lorentz boosting. We apply this approach to the search for Type I heavy Majorana neutrinos and compare our results with other techniques employed to investigate this phase space.

Kaeshav Danesh

Advisor: Rajiv Singh, UC Davis

Mean-Field Insights into Phase Transitions in the Transverse-Field Ising Model

The transverse-field Ising model is a simple model of quantum phase transitions. Studying these phase transitions could help explain interesting electronic phases in many materials. I studied an approximate version of the model based on mean-field theory and characterized the energy gaps of excited states at the phase transition. Lattice vibrations as an order parameter are also considered. 

Freya Derdeyn

Advisor: Theresa Lynn, professor of physics

Toward a Uniform Distribution of Two-Qubit Mixed States

In quantum information, operations often work as expected only for some quantum states. But it cannot be accurately determined for what fraction of two-qubit quantum states a particular operation works because there is no known uniform distribution over mixed states. The Bloch sphere provides a uniform distribution for one-qubit states, but this representation is not extensible to higher dimensions. Many authors have explored representations of two-qubit quantum states, but they have limited their attention to only pure states or subsets of mixed states. We use a parametrization of two-qubit mixed states introduced by Kong and Ting (2021) to move toward a uniform distribution over all two-qubit quantum states.

Ellen Ferranto

Advisor: Nicholas Breznay, assistant professor of physics   

Structural, Spectroscopic, and Electrical Characterization of Crystalline Sodium Rhodate Na(1-x)RhO2

Rhodates are a class of materials with potential novel crystal structures or superconductive properties. While some studies investigate single-crystal rhodates, here I report on the properties of Na(1-x)RhO2 created by oxidizing NaRhO2 powders. As sodium content decreases, we expect our compounds to evolve from insulators to electrical conductors. However, our samples do not undergo this metal-insulator transition, instead exhibiting mixed insulator-semiconductor behavior. In addition, changes in powder x-ray diffraction patterns indicate the emergence of novel compounds. I will present electrical transport properties like the semiconducting bandgap and localization length of these samples. The phases created by oxidizing NaRhO2 give insight into multi-phase rhodates and their byproducts.

Lucas Grandison

Advisor: Nicholas Breznay, assistant professor of physics

Exploring Techniques to Mitigate Voltage Noise in the Electrical Characterization of Large Area Graphene Field-Effect Transistor Sensors

Using graphene as a demonstration material, I have created graphene field-effect transistors (gFETs) to refine and develop methods to increase the precision of electrical conductivity measurements, including the resistivity and Hall Coefficient. Increasing the precision of gFET device characterization will allow us to use them as sensors capable of detecting the proximity effect of small-scale entities, such as single molecules or even photons. I’ve chosen to improve these delicate and small-scale gFET devices by creating new Hall Bar geometries to evaluate the variation in sample contact placement, by using sputtered gold electrical contacts a gold sputter to reduce electrical contact resistances, and by building a new measurement circuit with an external potentiometer to mitigate the effect of longitudinal resistance input.  

Lauren Henson

Advisors: Peter Senchyna, Carnegie postdoctoral fellow; Ann Esin, associate professor of physics

Investigating UV Nebular Emission in the Lowest Metallicity Dwarf Galaxies

Certain galaxies over 12 billion lightyears away were found to have unusual features in the ultra-violet (UV) part of their spectrum, including strong emission from triply-ionized carbon (C IV). We cannot resolve these galaxies directly, but they have features in their spectra that are consistent with star-forming dwarf galaxies. The goal of this research is to see if this emission can be found in the local universe by studying nearby dwarf galaxies. Models show that the strength of C IV emission scales inversely with a galaxy’s age and metallicity, so we study three young dwarf galaxies with less than 5% solar metallicity. We find significant C IV emission in all three galaxies, with one of our galaxies having C IV emission strength comparable to that measured in distant galaxies. 

Tanvi Krishnan

Advisors: Vatche Sahakian, professor of physics; Gianluca Petrillo, Stanford University

Trigger Simulation Analysis in the ICARUS Neutrino Detector

I have worked to validate the performance of the trigger simulation for the ICARUS neutrino detector, in comparison to the hardware trigger. By comparing simulation results and analyzing raw detector data, I have found several disagreements between the hardware and simulated trigger, which must be better understood in order for the simulation to provide an accurate model of the hardware. Through modifications of the trigger simulation to better match the hardware trigger, we are able to obtain more accurate estimations of the performance of the trigger system. 

Lucien Mallett

Advisors: Subramania Athiray Panchapakesan, university of Alabama; Ann Esin, associate professor of physics

DEM Inversion Failures During Solar Flares

Differential emission measure (DEM) inversion is a method of analyzing images of the Sun to characterize plasma temperatures in the solar atmosphere. However, during large solar flares, it becomes challenging or impossible to derive DEM solutions for all pixels in an image and during all time steps in an observation: the sudden brightness of these events results in instrumental artifacts; additionally, plasma in solar flares occurs at a wide range of temperatures and is expected to depart from equilibrium conditions. In this thesis, I present DEM analysis for two large solar flares. After removing instrumental artifacts, I demonstrate when and where DEM inversion methods fail, and suggest that these failures could be used to investigate non-equilibrium conditions in solar flares.

Arianna Meinking

Advisor: Theresa Lynn, professor of physics    

Improving Adaptive Quantum Entanglement Witnessing

Understanding whether a quantum state is entangled is imperative for both near and far term quantum communication. An entanglement witness is an observable whose expectation value is negative only for entangled states. We develop two-qubit entanglement witnessing protocols that use a subset of the measurements needed to characterize a state. When entanglement is not witnessed by a first set of measurements, we propose additional steps in an adaptive protocol with the goal of witnessing entanglement in a limited set of measurements. We present strategies, including one based on training a neural network, to make the optimal choices at each step in the witnessing protocol. With 56% of the measurements from an exhaustive set, we witness more than 72% of randomly generated entangled states. 

Catherine Phillips

Advisor: Theresa Lynn, professor of physics

Lessons From a Teaching Internship

This semester I did a teaching internship with a physics teacher at a local public high school. I worked with AP Physics 1 and AP Physics C students, both observing the class and leading certain days myself. I’ll discuss what my goals were going into this internship, the pedagogy behind them, and how I attempted to implement them. Then I’ll talk about how things actually worked in the classroom, what challenges I faced, and the things I learned.

Chris Ranlett

Advisor: James Eckert, professor of physics   

Synthesis and Resistivity Measurements of Lithium Purple Bronze

This project discusses the physical properties of lithium purple bronze including the quasi-1d behavior of the compound and how this is reflected in resistivity measurements through solid single-crystal samples. We discuss crystal lattices and the physical properties caused by the structure of the purple bronze, and the theory and procedure of back-reflected Laue diffraction, using this technique to orient the crystalline axes to perform resistance measurements along the proper dimensions of the material. We derive van der Pauw’s equation for resistivity of an isotropic solid and the elements of the resistivity tensor in anisotropic solid. We conclude with the results of attempted resistivity calculations using van der Pauw’s method and assess necessary procedural improvements.

Inq Soncharoen

Advisor: Rahulkumar Solanki, visiting professor of physics

Light Propagation in Cylindrically Symmetric Static (CSS) Gravitational Fields

In general relativity, gravity affects the path of light. For instance, light rays passing by a massive star bend due to the star’s gravitational field. In this project, we found cylindrically symmetric static (CSS) gravitational fields for which light ray trajectories coincide by examining the necessary and sufficient conditions for geodesics on one surface to remain a geodesic when parallel-projected onto the other CSS surface.

Lucien Tsai

Advisor: Lori Bassman, professor of engineering

The Impact of Atomic Ordering on the Ductility of Compositionally Complex Alloys

In alloy design, ductility is a macroscopic mechanical property that defines the capability of an alloy to undergo significant deformation. In this work, we investigate the correlation between atomic ordering, the arrangement of different atomic species on a crystal lattice, and ductility for compositionally complex alloys that have significant fractions of multiple atomic species. In particular, we study the CuZnMn brass alloy system with a known increase in ductility past a critical Mn concentration. By comparing this experimental observation with changes in the system’s atomic ordering from an increasing Mn concentration obtained using computational simulations, we aim to unravel the connection between atomic ordering and ductility.

Eritas Yang

Advisor: Daniel Tamayo, assistant professor of physics   

Secular Dynamics of Compact Three-Planet Systems

The final stage of terrestrial planet formation takes place after the protoplanetary disk dissipates. The ensuing giant impact phase of collisions and gravitational scatterings determines the planetary masses and orbital architectures that we see today. Understanding the chaotic dynamics driving these instabilities is therefore crucial for connecting disk formation models to observations.

It has long been known that the chaotic boundary for a pair of planets on closely spaced orbits is determined by mean motion resonances (MMRs). In particular, as one varies the separation between the two planets, one encounters MMRs whenever the orbital periods form integer ratios. Each of those resonances has a finite width, and the stability boundary is at the orbital separation where adjacent resonances start to overlap one another. However, the theoretical picture remains unclear when introducing even one additional planet, and empirical scaling laws for instability times from numerical simulations over the past three decades have had limited success.

Recent work suggests that instabilities in compact systems of three or more planets are still driven by the same MMR overlap mechanism, but one needs to additionally account for long-term secular dynamics. These secular perturbations lead to expansion and contraction in the MMR widths, thereby modulating the location where MMR overlap occurs. While the leading-order Laplace-Lagrange solution for the secular dynamics is well known, the requisite matrix diagonalization needs to be solved numerically, defying a closed-form solution for the stability boundary. However, in the so-called Hill limit where orbits are closely spaced, several simplifications make it possible to make analytical progress.

We present an analytical model for the secular dynamics of compact, co-planar three-planet systems. This provides not only analytical expressions, but also geometric intuition into the conserved Laplace-Lagrange modes driving the dynamics. In particular, we show that the Laplace-Lagrange modes are simple compositions of the eccentricity combinations that set the MMR widths. We will additionally present a simple expression for the expansion and contraction of MMRs and discuss its applications to obtaining a simple stability boundary for compact multi-planet systems.

Class Presentations

CLES 120: Games for Climate Change Literacy

Student presenters: Abraham Arias, Arjun Asija, Natalie Joy Burton, Harrison H. Chapin, Callie Dawson, Ally Dye, Ammar Fakih, Devanshi Guglani, Sadie Heckman, Julia Hsing, Savva Ignatov, Zeneve Jacotin, Jocelyn Livier, Emma Mohs, Chris Morales, Claire E. Partridge, Vani Sachdev, Connor Seto, Michelle Tran, YJ Tsai, Claire Vlases, Joan Wang, Allyson Yao

Advisor: Lynn Kirabo, Maria M. Klawe Assistant Professor of Climate and CS

In this course, students learned to use human-computer interaction methodologies, behavioral theories and the transformational framework to design three climate change literacy games to inspire positive behavior change in players.

CS186: Spatial Vision Tool Development

Student presenters: Isaac Chung, Joshua Garcia-Kimble, Larry Wang

Advisor: Calden Wloka, assistant professor of computer science

Spatial vision involves the recovery of three-dimensional information from two-dimensional images. This project involved building demonstrations and tutorials in topics foundational to spatial vision, including image correspondence and homographies, and stereo disparity and depth calculations.

E4 Introduction to Engineering Design and Manufacturing

Student Presenters

Aiming for the Stars Section 1: Thiven Anderson, James Cassidy, Ever Diaz-Ramos, Soon Young Kwon

The Current Conundrum Section 1: Nataly Mayison, Morgan Pulling, Jade Wong, Christian Wu

The Current Conundrum Section 2: Nicole Balsz, Allison Barker, Nicholas Dass, Luke Vlases

Hygiene Huts Section 1: Max Buchanan, Mia Celeste, Andre Mendoza, Eoin O’Connell, Jonathan Tabb

Hygiene Huts Section 2: Jula Gong, Tracy Han, Ivy McFetridge

Load ’Em Up Section 1: Imani Hernden, Carlos Ojeda de Silva, Samantha Riter, John Simon, Mayu Tatsumi

Load ’Em Up Section 2: Michelle Bazan, Jadyn Long, Abraham Rock, Stryker Scales, Raymond Siguencia

Reel Deal Section 1: Clara Caspard, Sheridan Dorsey, Cole Ellsworth, Quinn Miyamoto, Elodie Serres

Reel Deal Section 2: Kyra Burns, Hugo Guckert, Katie Latvakoski, Gavin Netherton, Adam Vanluvanee

Scratching Each Other’s Backs Section 2: Gabe Menendez de Alencar, Cooper Mixon, Jacob Sesate, Evan Siegel

Thru the Thick of It Section 1: Brock Bownds, Annette Chang, Sebastian Heredia, Gabrielle Reynolds

Thru the Thick of It Section 2: Broderick Bownds, Drake Gonzales, Joshua Ikehara, Josue Meraz

Advisors: Whitney Fowler, assistant professor of engineering; Mark Gale, visiting assistant professor of engineering; Qimin Yang, professor of engineering

E4 (Introduction to Engineering Design and Manufacturing) situates student teams as engineers contracted to work on a design project provided by an external client. These projects are open-ended and ill-defined and require students to employ conceptual design. Students work closely with clients, instructors, and the makerspace and machine shop to conceive of and develop a design solution as they navigate the complexity of the design process. These presentations represent the culmination of their work.

E80: Experimental Engineering

Student presenters:

Abdelmalek, Joseph
Alemayehu, Fanuel
Allgor, Ella
Anderson, Avery
Andrade Fernandes, Felipe
Angel, Emma
Arce, Natalie
Barr, Emily
Bellido, Marina
Blackett, Andrew
Brako, Adne
Brandt, Miranda
Brewer, Samuel
Burgos-Fallon, Santiago
Carlin, Jordan
Carreno, Jared
Coggshall, Caiya
Colorado, Haley
Cox, Jasper
Dada, Damilola
Davis, George
De Santos, Roman
Deng, XiaoLan
Dey, Kavi
Diaz Ruiz, Covi
Didrickson, Bryce
Dorsey, Sheridan
Elkaslasy, Leilani
Fain, Jacob
Fattahi, Abdullah
Gruian, Audrey
Han, Tay
Heathwood, Henry
Heinstein, Joshua
Hernandez, Cameron
Hickson, Corey
Horiguchi, Naomi
Hottenrott, Isabella
Hu, Leran
Huefner, Kathryn
Ihs, Massin
Jampana, Shreya
Jenkins, Maya
Jesse, Gaven
Jeter, Isaiah
Jobanputra, Nina
Kan, Madeleine
Kaufman, Troy
Kendrick, Emily
Kho, Megan
Knolton, Hailey
Kolt, Julia
Kotkosky, Daniel
Krasner, Alicia
Krishna, Vikram
Lambert, Charles
Lemos, Lucas
Liu, Amy
Liu, Jessica
Long, Kayla
Lopez, Vanessa
Lorenzana, Luis
Lu, Selina
Luu, Julien
Magdaleno, Celeste
Maguire, Noona
Manese, Julia
Mateo, Michael
McMurray, McKenna
Molinar, Matthew
Ngoga, Josaphat
Nguyen, Katrina
Osborne, Ian
Parizot, Victoria
Parker, Kanoa
Perry, Caden
Pham, Warren
Pratt, Delaney
Ragnartz, Marika
Robertson, Alex
Romanowski, Kala
Rosas, Rodrigo
Sedo, Will
Shaw, Katy
Smith, Avery
Smith, Ian
Smith, Natalie
Spoor, Slader
Stolzoff, Isabel
Stralka, Emmett
Tzunun Palomo, Cristina
Wang, Erin
Wexler, Sara
Williams, Andrew
Wu, Betsy
Zambrano, Wilson
Zheng, Richard

Advisors: Matthew Spencer, associate professor of engineering;  Josh Brake, assistant professor of engineering; Dre Helmns, assistant professor of engineering; Ethan Ritz, assistant professor of engineering; Qimin Yang, professor of engineering

Experimental Engineering is an engineering project course where students design robotic boats and submarines to carry out experiments of their choosing in a deployment in the ocean. The experiments range from engineering measurements of sensor accuracy to scientific measurements of healthy conditions for aquatic life.

ENG190 Sustainable Design / Special Topics in Engineering

Student presenters: Ayman Abdellatif, Holly Chen, Cheyenne Foo, Brayden Hedrick, Claudia Nanez, Claire Rafferty, May Ling Roberts

Advisor: Gordon Krauss, Fletcher Jones Professor of Engineering Design

The Sustainable Design course is designed to prepare students for the challenges and opportunities in the field of sustainable engineering and in design more generally. This course integrates practical methodologies with an understanding of environmental, societal, and economic impacts, emphasizing a holistic approach to design and decision-making.

Structured around project-based learning, the course encourages students to engage in life cycle assessments of real products, analyzing and proposing improvements that balance environmental responsibility with societal needs and financial viability. Through a curriculum that covers key concepts such as resource conservation, eco-toxicity, human toxicity, energy systems, and life cycle costing, students develop a robust framework for assessing the sustainability of engineering projects.

A distinguishing feature of the program is its use of the SimaPro software, enabling students to perform detailed life cycle assessments. This hands-on experience is complemented by lectures, case studies, and project work that foster an environment of active learning and collaboration. Reflective of its commitment to practical application, the course culminates in a final project where teams present their assessments and recommendations for sustainable design solutions, showcasing their ability to integrate environmental, financial, and societal considerations into engineering projects.

E191: Advanced Problems in Engineering

Student presenters: Caiya Coggshall, Elle Marsyla; Itzel Hernandez, Josiah Garan, Sara Wexler; Ruby Peterman; Clay Briggs, Gabriel Klinger, Sam Brewer, Rodrigo Rosas; Arya Mididaddi, Alex Martin, Joseph Abdelmalek, Marika Ragnartz; Mikayla Mann, Emily Kendrik, Izze Stolzoff

Advisor: Steven Santana, Iris and Howard Critchell Assistant Professor of Engineering

Members of the CuTE Lab present their findings and results from the 2023/24 Academic Year.

HSA 10

This seminar course introduces students to inquiry, writing, and research in the Humanities, Social Sciences, and the Arts, through focused exploration of a particular topic selected by the instructor in each section. To encourage reflection on the place of HSA within the Harvey Mudd curriculum, the course begins with a brief unit on the history and aims of liberal arts education. Writing assignments include a sub­stantial research paper on a topic of interest chosen by the student in consultation with their instructor. The course ends with student research presentations in each section, followed by a Presentations Days event featuring the best presentations from across all sections.

Shanahan Project: Smoke Mask Rescue Drone

Student presenters: Dominick Quaye, Victor Shia

Developing a drone to deliver smoke inhalation masks to people in apartment building fires through windows.

Making Monsters (exhibition in Sprague Gallery)

Student presenters: Sarah An, Brandon Bonifacio, Eloise Burtis, James Clinton, Kaeshav Danesh, Leilani Elkaslasy, Zeneve Jacotin, Elena Kryukova, Noah Gabor, Golda Gene Grais, Beatrice Rose Hruska, Noah Limpert, Kaliyah Keita, Kenneth Mitchel, Maria Jose Najas, Anna Shobe, Jordan Stone, Mikayla Spencer Stout, Emmett Stralka, John Tjaard van Loben Sels, Ethan Vazquez, Jasper Wood, Trinity Zhang

Advisors: Ken Fandell, professor of art; Kyle Thompson, assistant professor of philosophy; Ambereen Dadabhoy, associate professor of literature

Physics 64: Mathematical & Computational Physics

Advisor: Vatche Sahakian

Thirty-one students present their final computational projects on a topic at the interface of physics, mathematics and computer science.