College of Science & Health (CSH)

Characterization of Orchil Dye-yielding Lichens in the Driftless Area  

Major:  Biology

Mentor: Dr. Anita Davelos

Abstract: As consumers rethink their relationship to waste and allergens in the textile industry, there has been a renewed interest in natural dye practices. Some species of lichen produce secondary metabolites that are known sources of dye-yielding pigment, and lichens have been used in textile dyeing for thousands of years. The identities of lichen specimens collected in the Driftless Area of western Wisconsin were confirmed using a combination of morphological characters, chemical tests and Sanger sequencing of the ITS region of the rDNA. A chemical analysis of the specimens was performed using NMR and the secondary metabolites known to create dye-yielding pigment were characterized. Dye extractions using the ammonia method were created from some species and applied to textile samples. This poster provides insight into a historically significant use of lichens and elaborates on the chemistry of orchil lichen dyes.

Quantifying Indicators of Wound Inflammation

Major:  Biology

Mentor: Dr. Cord Brundage

Abstract: The healing rate of companion animals is difficult to determine after surgery due to the lack of standard collectable data available to indicate a healthy wound site. Animals are unable to give feedback on their wound status using the pain scales that are typical in human medicine. To provide a basis for scoring healing rates this study will focus on measuring variables that correlate with the cardinal signs of inflammation including redness, skin hydration level, skin elasticity, and skin surface temperature. Measurements will be taken with dermatological tools that objectively provide numerical values for each variable. These tools have been purchased by UWL and Dr. Brundage’s lab, and they will stay with UWL at the conclusion of the project. Surgical wound sites will be analyzed on an estimated 24 cats and dogs currently residing at the Coulee Region Humane Society who are recovering from necessary procedures such as spays and neuters. Individual participants will be repeatedly measured and compared with their previous measurements every 24 hours for up to 10 days. Statistical analysis will be performed to determine significance. With objective numerical data linked to healing rates, post-operative healing treatments can be more successfully assessed. With reliable correlations established, the vast field of wound treatments in animal care can be more accurately scrutinized.

Efficient Antenna Array Designing using Reinforcement Learning

Mentor: Dr. Dipankar Mitra

Abstract: This research presents an end-to-end model for antenna array synthesis, integrating machine learning and reinforcement learning techniques. We propose a multi-stage ensemble model to predict optimal geometric parameters, leveraging data-driven methods for improved accuracy. These predicted parameters serve as inputs to a reinforcement learning (RL) -based model, enabling the design of a cognitive antenna array. To eliminate the need for real-time interactions with a physical environment, we develop an offline reinforcement learning approach based on the Deep Q-Network (DQN) algorithm. This method ensures efficient learning while reducing resource constraints. To facilitate training, we generate a static dataset using CST and COMSOL Multiphysics simulations, mimicking real-world interactions. The trained model is then applied to antenna design, demonstrating that the predicted geometric parameters align closely with simulation results. Our approach highlights the effectiveness of combining ensemble learning with reinforcement learning for scalable antenna array synthesis, particularly in resource-limited environments where real-time experimentation is impractical

Experiences of the Social Processes of Dying

Major:  Public Health and Community Health Education

Mentor: Dr. Angela Geraci

Abstract: Background: Social support is vital to the health and well-being of all individuals. Little is known about the social support experienced by individuals during the dying process. Purpose: This study will examine the social processes of dying, including the value of social relationships and changes in these social relationships, from the perspective of the dying individual. Previous research has looked at social relationships in older adults, but limited research has looked specifically during the dying process. The limited existing research around social support during the dying process has failed to look at multiple drivers for changes in social relationships during the dying process. By looking at these changes and the drivers for these changes, this study aims to identify whether or not the dying individual is solely responsible for the changes in their social relationships. Methods: Using a phenomenological study design, in-depth interviews will be conducted with 10-15 participants in order to gather qualitative data about their lived experiences. After conducting these interviews, themes among the responses will be analyzed in order to answer the research questions. Results: This research will shape how the dying process is looked at from a social perspective and will guide future research on what needs to be done in order to better support individuals during the dying process. 

Exploring camp experiences on parental subjective well-being and sense of community utilizing photovoice

Major:  Recreational Therapy

Mentor: Dr. Jennifer Taylor

Abstract: A 2024 Surgeon General Advisory Report communicated the unique stressors that affect the mental health of parents including time demands, health and safety, isolation, loneliness, and technology such as social media. The report also included a call to action to conduct additional Community-Based Participatory Research (CBPR) utilizing mixed-methods approaches to understand the experiences of parents and caregivers and their mental health challenges to determine how programs (e.g. camps) can support parental mental health and well-being. CBPR engages community members, organizational representatives, and academic researchers during the entire research process. This study will employ a CBPR approach with a convergent parallel mixed-methods design. Data will include pre-post surveys, field observations, and photovoice. Photovoice is a photography-based methodology to prompt participants to share their experiences, perspectives, and feelings after taking pictures. Participants will take photographs during a 7-day family camp experience and then be interviewed to explain the significance of the pictures they took, while exploring potential effects of the camp experience on their subjective well-being. Participants will also complete a Positive and Negative Affect Scale (SF) and Brief Sense of Community Scale before and after attending a weeklong camp in the upper Midwest. Researchers will assess changes in positive and negative emotion levels before and after attending the camp and will analyze sense of community levels experienced at camp. Results will be shared with camp administrators to identify specific elements of the camp experience (e.g. social connection, recreational activities, immersion in nature) while exploring the role that family camps parental subjective welling-being. Finally, photovoice interviews will be recorded and compiled into a video that can be used by the camp to share potential parental mental health and sense of community impacts. 

Determining Residues Important for Differentiating Mammalian and Bacterial Alkaline Phosphatase Activity

Major:  Biochemistry 

Mentor: Dr. Daniel Grilley

Abstract: Alkaline phosphatase (APase), a ubiquitously expressed enzyme, catalyzes the hydrolysis of phosphomonoester bonds, resulting in phosphate group removal from molecules. For optimal enzymatic function, two zinc ions and one magnesium ion are required. Despite conservation of the overall structure and the metal ions used, mammalian and bacterial APases have significantly different turnover rates, substrate specificity, and strength of interaction with the metal ions. A structural comparison of human placental alkaline phosphatase (HPAP) and E. coli alkaline phosphatase (EcAP) revealed that none of the ten residues that form direct contacts with the metal ions vary significantly amongst APases. However, two residues close to the magnesium binding site differ between HPAP and EcAP. These primary residues position water molecules that bind to the magnesium ion. The structural comparison also revealed three additional secondary residues that may play a role in modulating the position of the primary residues. We hypothesize that the variation in the primary and secondary residues contributes to the differences in metal ion binding and enzyme activity. To test the importance of these metal coordinating residues, we have systematically introduced site specific mutations at the five residues (two primary and three secondary) in EcAP to match the conserved residues found in mammalian enzymes. Our data show that both the primary and secondary residues affect the ability of the enzymes to bind to the correct metals. We show that these residues also affect the ability of the enzymes to exchange metals from within the active site. Finally, these residues appear to affect the ability of small molecules to interact with the metals. The results of these studies will be discussed in terms of the dynamics of the active site for mammalian versus bacterial enzymes and the implications for the environments where these enzymes are active.

Tadpole Habitat Research

Major:  Pre- Vet Biology

Mentor: Cord Brundage

Abstract: This study looked into habitat selection and behavioral patterns of tadpoles in controlled tank environments to better understand how structural features influence their spatial preferences. Two experimental tanks were set up, each containing a distinct artificial structure (one blue, one orange) to simulate environmental heterogeneity. Tadpoles were observed over multiple trials, and the time spent in proximity to each structure was recorded. Results showed a consistent preference for the blue structure, suggesting that coloration or spatial positioning may play a role in habitat selection. These findings contribute to our understanding of microhabitat preferences in early amphibian development and highlight the importance of environmental complexity in designing captive studies or conservation interventions. Future research should explore the sensory or ecological drivers underlying these preferences to inform habitat restoration and management efforts for amphibian populations.

Electrochemical Investigation of a Modified Iron Phthalocyanine Catalyst for Green Oxidation Reactions

Major:  Chemistry

Mentor: Dr. Rob McGaff

Abstract: Catalysis, a central principle of the growing field of green chemistry, reduces waste and enhances reaction efficiency by enabling chemical transformations without the need for large amounts of reactants. This project investigates the redox behavior and catalytic mechanism of an iron phthalocyanine derivative, FeLX, designed for the oxidation of alcohols to aldehydes or ketones—valuable transformations for industrial chemistry and sustainable feedstock utilization. The iron center in FeLX is redox-active. Meaning it has the ability to gain or lose electrons which is the heart of chemical reactions. Electrochemical techniques, including cyclic voltammetry and square wave voltammetry, were employed to probe its electronic properties. Preliminary results confirm that FeLX undergoes redox transitions, although these events occur at more extreme potentials compared to typical iron-based complexes. This suggests that the ligand environment stabilizes the iron center, possibly inhibiting certain electron transfer processes. Moreover, the redox inactivity implies a more complex mechanism by which the transformation occurs, not a simple electron transfer but a possible rearrangement of the FeLX structure. Interestingly, FeLX also shows signs of aggregation, the clumping of many FeLX molecules, in solution. While aggregation is typically undesirable in homogeneous catalysis, it presents an opportunity to develop a heterogeneous catalytic system (e.g., solid phase FeLX and liquid alcohol). Future work aims to exploit this behavior by immobilizing FeLX onto conductive surfaces, enabling surface-controlled catalysis under applied potential, opening the possibility for green, electrochemically-driven oxidation reactions.

 Green and Economical Catalytic Processes for the Oxidation of Alcohols

Major:  Biochemistry

Mentor: Dr. Rob McGaff

Abstract: Green chemistry is a developing practice within the larger chemistry community whose main goals are to reduce the use and production of harmful compounds and to decrease energy usage. Traditional alcohol oxidations do not follow these guidelines as they use toxic reagents such as chromate species, which are carcinogenic and incredibly hard to dispose of. Other less toxic reagents can provide ways to oxidize alcohols but suffer from requiring harsh reaction conditions or poor specificity. To tackle these issues, we have utilized an iron-based catalyst known as FeLX in combination with various thiols to achieve alcohol oxidation under mild reaction conditions. Alcohols are a versatile building block and can be oxidized to create many classes of compounds such as aldehydes, carboxylic acids, and esters, all of which have unique relevance in manufacturing and industry. In creating these compounds, we can both provide greener procedures for synthesis as well as lay the framework for other types of oxidation reactions like epoxidation.

Characterizing the biochemical properties of a potential oxygen-binding hemerythrin in the soil bacterium Myxococcus xanthus

Major:  Microbiology

Mentor: Dr. Daniel Bretl

Abstract: Myxococcus xanthus is a ubiquitous soil bacterium that requires oxygen for energy production and growth. However, since the concentration of oxygen in the soil is highly variable, M. xanthus must have mechanisms to sense and respond to this changing concentration, and to have proteins and enzymes that allow for efficient storage and use of oxygen. The Bretl Lab has identified that M. xanthus encodes six distinct oxygen-binding proteins belonging to a protein family called hemerythrins. In general, hemerythrins are small, soluble proteins predicted to help bacteria survive periods of low oxygen. Previous work in the Bretl Lab, carried out by M.S. student Mason Stenzel, sought to functionally characterize the six predicted M. xanthus hemerythrins, of which four were confirmed. However, one of the predicted hemerythrins (MXAN_7402) could not be purified and remains uncharacterized. This may be due to a significant discrepancy between this protein’s predicted structure and the other hemerythrins’ predicted structures. Specifically, MXAN_7402 is predicted to have a long unstructured tail on both the N- and C-terminus that may decrease the solubility. To increase the solubility of MXAN_7402, we have truncated the protein, retaining only the functional region of the protein, which is distinct from the unstructured tails. This should not affect the structure or function of the domain of the protein that binds oxygen, allowing for the characterization by UV-spectroscopy as a hemerythrin. Overall, we expect that removing the unstructured tails of MXAN_7402 will increase its solubility, enhance purification success, and enable characterization as a hemerythrin. 

All Optical Switching with ZnO Thin Films

Major:  Applied Physics

Mentor: Dr. Eric Gansen

Abstract: In this work I report on the development of an All-Optical Switch based on ZnO/ZnMgO quantum wells, that operates in the UV spectral region. This switch is similar to a light switch, except instead of modulating the flow of electricity using mechanical control lever it modulates the flow of light using and optical control. This work builds on previous studies by Dr. Eric Gansen and Dr. Seth King that demonstrated how the Quantum-Confined Stark Effect can be used to modulate the transmission of signal pulses using stronger control pulses of light. However, in that work the turn-off time of the switch was observed to be relatively slow (~100 ns) limiting the overall speed of the switch. Here I study the effect quantum-well width has on the turn-off time of the switch and the overall effectiveness of the switching action.

Using RT-qPCR to Measure the Impact of the Bottleneck Effect on Influenza A Replicative Fitness

Major:  Microbiology

Mentor: Dr. Peter Wilker

Abstract: Influenza A virus (IVA) has high genetic diversity and mutates rapidly but the population is heavily influenced by bottleneck events, or when population sizes is suddenly reduced, occurring when the virus is transmitted between hosts. To determine the impact of these events, an influenza virus, A/Victoria/361/2011 (H3N2), was repeatedly exposed to bottleneck events with strict bottlenecks producing a virus with dilapidated viral fitness, referred to as the “dilapidated virus” (DV). The DV was passed through a series of larger bottlenecks which produced a “recovered virus” (RV). To characterize the RV, next-generation sequencing (NGS) is used. NGS is more sensitive than Sanger sequencing, giving a higher discovery capacity. Sequences from the RV, DV, and parent virus are compared to understand any mutational pattern. To assess the viral fitness, I am developing a reverse-transcription quantitative polymerase chain reaction (RT-qPCR). Plaque assays are typically used to assess quantity of infectious viral particles. This method is both cost and time consuming. Results from the RT-qPCR will be compared to results from the plaque assay. If both produce proportional results, RT-qPCR will be used to quantify virions moving forward. This work will improve our understanding on the impact of serial bottleneck events on the evolutionary trajectory of influenza viruses.

Characterization of Presumptive Antibiotic-Resistant Bacterial Isolates from Irrigation Water

Major:  Biology

Mentor: Dr. Xinhui Li

Abstract: Antibiotic resistance has become a major public health crisis. Beta-lactam antibiotics are the most commonly used class in the U.S. However, some bacteria produce β-lactamases, including extended-spectrum β-lactamases (ESBLs), which degrade a broad range of β-lactam antibiotics. Carbapenems, a subclass of β-lactams, are often used as “last-resort” antibiotics, but some bacteria have developed resistance to them by producing carbapenemases. ESBL-producing Enterobacterales, as well as carbapenem-resistant bacteria, including carbapenem-resistant Enterobacterales (CRE), are of particular concern. Many of them are opportunistic pathogens and can transfer resistance genes to other bacteria. Both ESBL-producing Enterobacterales and CRE are listed as urgent and serious threats by the CDC. Our studies have found these resistant bacteria in fresh vegetables, therefore, identifying potential sources of contamination, including irrigation water, is essential. As part of a field trial in California, we collected irrigation water used to grow carrots and lettuce. Samples were processed through filtration, enrichment and selective media to isolate presumptive ESB-producing Enterobacterales and carbapenem-resistant bacteria. With the presumptive isolates, disk diffusion assays will be used to confirm ESBL production, as well as carbapenem resistance, and antimicrobial susceptibility profiles of confirmed isolate. Carbapenemase production and typing will be assessed using mCIM and eCIM tests. Selected confirmed isolates will undergo whole genome sequencing. Species will then be identified through rMLST, resistance genes will be identified with CARD, mobile genetic elements will be analyzed to determine if resistance genes are plasmid-borne, and conjugation experiments will be conducted using E. coli DH5α as the recipient. This project aims to assess and characterize ESBL-producing Enterobacterales, as well as carbapenem-resistant bacteria from irrigation water for vegetables to determine potential contributing factors to antibiotic resistance in vegetables.

Ectomycorrhizal Fungal Diversity and Functional Effects on Eastern Hemlock (Tsuga canadensis) Seedlings in the Kickapoo Valley

Major:  Plant and Fungal Biology

Mentor: Dr. Anita Davelos

Abstract: Tsuga canadensis (Eastern Hemlock) is a long-lived, shade-tolerant conifer native to northeastern North America. In southwestern Wisconsin, disjunct relict populations of old-growth Eastern Hemlock persist in Wildcat Mountain State Park within the unglaciated Kickapoo River Valley. As a foundation species, T. canadensis plays a critical role in regulating microclimates, stabilizing soils, and supporting diverse plant and animal communities. However, these populations face increasing threats from invasive pests, habitat loss, and climate change, placing the long-term stability of these ecosystems at risk. Eastern Hemlocks form obligate symbiotic relationships with ectomycorrhizal (ECM) fungi, which enhance water and nutrient uptake in exchange for photosynthetically derived carbohydrates. ECM fungi also contribute to seedling establishment, pathogen resistance, and nutrient cycling. Despite their ecological importance, little is known about the diversity and distribution of ECM fungi associated with T. canadensis in disjunct Midwestern populations. This study assesses both the morphological diversity of the ECM fungi associated with Eastern Hemlocks in the Kickapoo Valley as well as how well seedlings of T. canadensis develop and grow under different ECM treated soils. Soil cores were collected from three sampling points at each of nine hemlock-dominated sites. Root tip samples were analyzed to quantify ECM diversity using metrics such as species richness and Shannon diversity index. This research aims to identify how ECM fungal communities vary across fragmented habitats and how these communities may influence the survival and regeneration of T. canadensis. In addition, seeds were obtained from the Wisconsin DNR, Hayward State Nursery for an experiment to examine seedling performance in different ECM treated soils. These findings will contribute to a better understanding of symbiotic relationships in fragmented old-growth forests and provide valuable information for future conservation and restoration efforts. 

Understanding how Mammalian Alkaline Phosphatases Target Proinflammatory Factor

Major:  Biochemistry

Mentor: Dr. Dan Grilley

Abstract: Alkaline phosphatases (ALPs) are enzymes that are critical for different organisms’ phosphate metabolism, with mammalian and bacterial forms exhibiting distinct substrate specificities. Mammalian ALPs come in multiple varieties with specialized functions. The placental ALP (e.g. human placenta alkaline phosphatase – HPAP), is important for antibody transfer from mother to fetus. While intestinal alkaline phosphatase (e.g. calf intestinal alkaline phosphatase – CIAP), is important for dephosphorylating lipopolysaccharides and thus modulating intestinal inflammation response. These two mammalian ALPs specifically target nonpolar (greasy) molecules. Escherichia coli alkaline phosphatase (EcAP) lacks this targeting of nonpolar molecules and works as a more general phosphate scavenging enzyme. This project aims to determine the molecular basis of these differences in specificity by comparing structural and biochemical properties of CIAP, HPAP, and EcAP. Initial structural and conservation analysis of the mammalian enzymes suggested four residues that potentially determined the differences in specificity for nonpolar molecules. By systematically introducing these residues to EcAP, we have determined the importance of these residues for inducing binding of nonpolar molecules to EcAP. To determine the molecular basis for nonpolar molecule binding, we have systematically tested closely related small molecules. Finally, we are using protein crystallography and x-ray diffraction to determine the structures of the variant proteins in the presence and absence of the nonpolar molecules that inhibit the enzymatic function. This research contributes to the understanding of enzyme specificity and may have broader implications for drug design and inflammatory disease treatment and management.

Patterns of DOC Biodegradation and Composition Shifts in Stratified Lakes of the Northern Lakes and Forest Ecoregion

Major:  Biology

Mentor: Dr. Eric Strauss

Abstract: Dissolved organic carbon (DOC) is a vital component of the global carbon cycle and plays an essential role in freshwater biogeochemical processes. DOC can originate from within the system (autochthonous), primarily produced by photosynthetic organisms and generally more bioavailable, or from external terrestrial sources (allochthonous), which tend to be less bioavailable due to their complex, aromatic structures. DOC is microbially degraded via respiration, producing carbon dioxide, a greenhouse gas contributing to climate warming. This study investigates the biodegradability of DOC across nine lakes in the Northern Lakes and Forest Ecoregion, located on the University of Notre Dame Environmental Research Center (UNDERC) property. The project explores how DOC biodegradability varies (1) across lakes with different DOC concentrations, (2) between epilimnetic and hypolimnetic layers, and (3) over time. Incubation experiments were conducted for 28 days using water samples collected in triplicate from both the epilimnion and hypolimnion of each lake. Lakes were categorized as having low (0–10 mg/L) or high (10–30 mg/L) DOC concentrations. Samples were analyzed at five time points (days 0, 2, 7, 14, and 28) to track temporal changes. DOC concentrations were quantified via high-temperature combustion, while composition was assessed using spectrophotometric proxies—specific ultraviolet absorbance at 254 nm (SUVA254) and the E2:E3 ratio. I expect that lakes with low DOC will contain primarily autochthonous DOC that is highly bioavailable compared to lakes with high DOC, that are likely to have more autochthonous and less bioavailable compositions. I further expect that generally, epilimnion waters will contain more bioavailable DOC than hypolimnetic waters. Finally, I expect that biodegradation will result in a shift in DOC composition characterized by increased molecular weight molecules and larger aromatic structures, with the most rapid shift occurring early as more bioavailable carbon is consumed preferentially, which is supported by preliminary results.

Expression of NmpR-dependent promoters in Myxococcus xanthus under hypoxic conditions

Major:  Microbiology

Mentor: Dr. Daniel Bretl

Abstract: Myxococcus xanthus is a gram-negative, rod-shaped bacterium that exhibits extensive cooperative social behaviors, including type IV pili (T4P)-dependent motility, also known as social (S) motility. Other complex behaviors, like multicellular development and microbial predation, require S-motility. The NmpRSTU multi-component regulatory system is involved in T4P-dependent motility and has been implicated in oxygen utilization. Notably, M. xanthus is an obligate aerobe, suggesting that gene regulation by the NmpRSTU system may be critical for survival in low-oxygen soil environments. The current model proposes that in hypoxic conditions, NmpS, a hybrid sensor kinase, detects low oxygen and phosphorylates the response regulator NmpR, which then activates transcription of genes involved in oxygen utilization. To investigate this regulation, in vivo transcription from NmpR-dependent promoters was analyzed using a lacZ reporter in strains grown under hypoxic conditions. Preliminary results indicate that at least two promoters demonstrate increased transcription under hypoxic conditions compared to ambient oxygen levels. Further investigation will provide insight into which genes are particularly important for the M. xanthus response to low oxygen.

Soil Chemistry Analysis to Assess Early American Fur Trade Activities at Madeline Island Archeological Site

Major:  Chemistry with an emphasis in Environmental Science

Mentor: Dr. Kristofer Rolfhus and Heather Walder

Abstract: Prior studies at the Grand Portage fur trade site in northeastern Minnesota suggested that elevated soil mercury (Hg) concentration was likely associated with the trade of vermilion, a pigment known as “cinnabar” or mercuric sulfide (HgS). To test this relationship at another trade location, soil cores from Madeline Island at the 1793-1835 CE Northwest Company and American Trade Post archeological site (47-As-0007) were analyzed to determine if mercury can be used as a tracer of historically documented late eighteenth to early nineteenth century fur trade activity at this site. The core samples were examined for archaeological artifacts that would aid in detecting human presence. Then, the site sediments were homogenized and tested for mercury using atomic absorption spectroscopy. Concentrations of copper, lead, arsenic, and iron were also obtained using ICP spectroscopy to help identify any patterns relating to past human activity at the site. A loss on ignition test was also performed to estimate the amount of organic matter in the soil and its influence on metal concentration. Any elevated Hg concentration found could indicate that historic vermilion trade occurred at this trade post.

Open-Eye EEG for Biometric Security: A Deep Learning Approach

Major:  Computer Science & Computer Engineering

Mentor: Dr. Rig Das

Abstract:

Traditional biometric systems are increasingly vulnerable to spoofing attacks, motivating the exploration of electroencephalogram (EEG) signals as a more secure alternative. EEG patterns are inherently unique to individuals and difficult to replicate, making them promising for authentication applications. However, developing reliable EEG-based systems faces challenges including cross-session variability and high-dimensional data processing.

This research develops a deep convolutional neural network (CNN) for EEG-based biometric authentication across different recording sessions. We collected EEG data from 21 subjects during two separate sessions, each containing 40 five-second templates recorded during eyes-closed, eyes-open, and motor imagery states. Data preprocessing employed 8-12 Hz bandpass filtering to isolate alpha rhythms, which exhibit strong subject-specific characteristics.

Our CNN architecture utilises a separable convolution approach: temporal convolutions first extract patterns within individual EEG channels, followed by spatial convolutions that learn inter-channel relationships. The network progressively downsamples temporal information whilst extracting increasingly complex features, ultimately producing a 128-dimensional biometric embedding. To combat overfitting inherent in high-dimensional EEG data with limited samples, we implemented aggressive regularisation including dropout rates up to 70%, L2 penalties, and batch normalisation throughout the network.

The authentication system employs majority voting across multiple templates to enhance reliability. Key innovations include the temporal-spatial separation strategy and extensive regularisation techniques tailored for small-sample, high-dimensional biometric data. This work advances cognitive biometrics by demonstrating how deep learning can extract persistent neural signatures across recording sessions, with implications for developing secure, continuous authentication systems. Future work will investigate larger participant pools and extended time intervals between sessions to further validate the approach's real-world applicability.

Biodiversity and Biogeography of Hawaiian Fungi

Mentor: Dr. Todd Osmundson

Abstract: In the Hawaiian archipelago, fungi play roles along all points of the symbiotic spectrum. From mutualists with plants, to parasites of the culturally significant 'Ōhi'a lehua trees. While species of fauna and flora are still being described from Hawaii, rigorous and nearly complete species inventories exist. For funga, no such baseline knowledge has been achieved. General biodiversity, as well as biogeographic status of species of are foundations for conservation work. In the Hawaiian archipelago, previous biogeographic work of fauna and flora has informed both conservation and the cultural stories of the Kamaʻāina, the Hawaiian people. Through the molecular and traditional study of fungal collections from the islands of Hawaii, Maui, Kauai and Oahu, this research pairs traditional taxonomic methods with modern tools of DNA sequencing to generate a baseline knowledge of fungal biodiversity and biogeography in the archipelago. DNA sequences of the nr(ITS) region will be compared to publicly available sequences and against null-model to assess the biogeographic signal. Through understanding the diversity and biogeographic signal of Hawaiian fungi, we can better steward Hawaiian ecosystems under threats of development and invasive species.

Interactions Between the Gut-Microbiome and Circadian Rhythm in Drosophila melanogaster

Major:  Biology

Mentor: Dr. Alder Yu

Abstract: Circadian rhythms are internal biological cues that regulate behavior and physiology over a roughly 24-hour period and are observed across a wide range of organisms. These rhythms persist independently of environmental stimuli but are also influenced by external signals such as light and food availability. Metabolites produced by the gut microbiome influence the circadian rhythm through changes in gene expression. At the same time, the circadian rhythm influences the composition of bacteria found within the gut microbiome throughout the day. In this research, the effects of the gut-microbiome on the circadian rhythm were observed in the fruit fly (Drosophila melanogaster). We compared axenic (germ-free) flies, which lack a gut microbiome, with conventionally raised flies that maintain a typical microbial community. Feeding activity, a behavior regulated by circadian rhythms, was monitored to determine differences in timing and pattern between the two groups. This approach allowed us to isolate the contribution of the microbiome to the regulation of circadian-driven behaviors. Our preliminary results suggest that the presence of a gut microbiome affects temporal regulation of feeding behavior in Drosophila. These preliminary findings support the idea that gut microbes play a functional role in modulating circadian behaviors and highlight the importance of microbial-host interactions in circadian homeostasis. 

Stability and function of Salmonella copper resistance protein with changes to non-polar residues

Major:  Biochemistry

Mentor: Dr. John May

Abstract: Copper ions are widely used as antimicrobial agents to kill bacteria since high levels are toxic to living cells. However, some bacteria have evolved mechanisms to survive copper exposure. In Salmonella enterica, a lipoprotein called DcrB has been found to show resistance to high levels of copper ions. The goal of this research is to investigate the specific structural features of DcrB that allow it to enable copper resistance. Previous research has shown that mutations to the N-terminal beta hairpin region of DcrB decrease the overall function of the protein. For current experimentation, we mutated several non-polar residues within the beta-hairpin to either medium length or short length residues. To investigate the stability of these non-functional mutants, we used circular dichroism with and without copper added to the protein. We will also be analyzing the oligomerization of the DcrB mutants with gels and cross-linking assays. These findings will help us understand how the DcrB protein functions to resist the antimicrobial properties of copper ions. Ultimately, this will be the first step to developing strategies to overcome bacterial resistance to metal ions such as copper. 

Using target capture to resolve species complexes within the genus Aphyllon (Orobanchaceae)

Major:  Biology

Mentor: Dr. Adam Schneider

Abstract: Aphyllon are a group of flowering plants that live as parasites, attaching to the roots of other plants to obtain nutrients. Many Aphyllon species look very similar, which has made it difficult for botanists to clearly define species boundaries or understand how they are related to each other. This summer, I did work to help advance my project of building a phylogenetic tree for this genus. This included reaching out to herbaria and users of the citizen science website iNaturalist to request plant tissue samples, performing DNA extractions, and preparing DNA libraries for a method called target capture. Target capture will allow us to isolate 353 specific genes of interest from all the DNA. I also reviewed scientific literature and tested different software tools that I can use for data analysis. The DNA sequencing step (target capture) will be completed before the end of the summer. This project will generate new genetic data that can help clarify how Aphyllon species are related and improve our understanding of their evolution.

Refinement of Deep Learning Models for Inventorying Endangered Hill Prairie Ecosystems

Major:  Biology

Mentor: Dr. Adam Schneider

Abstract: Hill prairies are unique, rare remnants of a once expansive prairie landscape and are crucial habitats for rare and endangered species. Land-use changes, urbanization, and invasive species have severely encroached on these prairies, yet comprehensive inventories to inform conservation remain scarce. Manual surveys, though useful, are time-consuming, expensive, and often impractical on large scales. To address this gap a Convolutional Neural Network (CNN) classification model was created for detecting remnant hill prairies in satellite imagery. Preliminary results show that this method achieves high overall accuracy yet struggles in balancing false positives and false negatives: refined CNNs tend to reduce over-classification but risk missing more prairie sites. Despite these trade-offs, our findings underscore the potential of deep-learning approaches to rapidly and repeatedly map hill prairies over wide areas. Future refinements—such as integrating additional environmental data layers, using dimensionality reduction techniques, and expanding the training dataset—could further enhance classification performance. Ultimately, these enhancements aim to support more efficient, data-driven approaches to prairie conservation and management.

Comparative immunotoxicity of PFHxS and PFOS in larval zebrafish and fathead minnows

Major: Biology Aquatic Science

Mentor: Tisha King-Heiden

Abstract: We continue to learn about the effects of per and polyfluoroalkyl substances (PFAS) on the health of humans and wildlife.  The negative health effects of these “forever chemicals” used in multiple consumer product range from cancer, neurotoxicity, and reduced vaccine response. The impact of exposure to these contaminants on the immune system remains poorly understood.  The innate immune system is the body’s first line of defense against pathogens such as viruses, bacteria or fungi. The innate immune system responds by producing a “respiratory burst” of reactive oxygen species (ROS) that function to kill the pathogen. Suppression of this response could be detrimental for an organism by increasing its susceptibility to disease. The focus of my research this summer is to assess and compare the effects of chronic exposure to various PFAS on the innate immune response in two species of fish used in environmental toxicology, zebrafish (Danio rerio) and fathead minnows (Pimephales promelas). Fish are exposed to environmentally relevant concentrations of PFAS via waterborne exposure beginning just after fertilization through completion of early larval development. A standardized tail wounding assay will be used to count neutrophils, the immune cells response for ROS production, in the caudal fin of fish after being wounded. This endpoint is closely linked to my previous work that quantified ROS through the respiratory burst assay. I hypothesize that PFAS will cause a dose-dependent suppression of neutrophil recruitment in both zebrafish and fathead minnow larvae with zebrafish being more sensitive. An increased susceptibility to disease is one consequence of a suppression of the innate immune response. Findings from my studies aim to bridge the gaps of knowledge regarding innate immune health and PFAS, and will provide data for regulatory agencies to use for setting water quality standards.

The Biogeography and Systematics of Xylariaceous Fungi on Polynesian Islands

Major:  Biology

Mentor: Dr. Todd Osmundson

Abstract: The xylariaceous fungi are an enigmatic group of macrofungi that are important wood decomposers, but they also live in plant leaves as endophytes with unknown effects on the host. Currently, there is nearly no knowledge of their biodiversity and evolutionary origins in remote areas of the world like Polynesia. Dried specimens of xylariaceous fungi from Mo’orea (n=35), Kaua’i (n=25), Oahu (n=13), and Hawai’i (n=9) were borrowed from herbaria. All specimens were morphologically identified to species when possible. DNA extractions were performed for all specimens and two genetic loci (ITS and alpha-actin) were PCR-amplified with Illumina tagged primers. The final PCR products were purified through bead-cleaning and pooled into a DNA library sequenced by the University of Wisconsin-Madison using the Illumina MiSeq. The forward and reverse reads were joined, primer tags were removed, and highly similar sequences were grouped into variants through shell scripts in BASH. The sequence reads still need to be aligned and run through a maximum likelihood simulation before the phylogenetic tree can be generated. The phylogenetic tree will provide insight into the evolutionary relatedness among xylariaceous fungi from Polynesia. 

Effect of PFAS on Jaw Structure and Prey Capture in Zebrafish (Danio rerio)

Major:  Microbiology

Mentor: Dr. Tisha King-Heiden

Abstract: Per- and poly-fluoroalkyl substances (PFAS), otherwise known as “forever chemicals”, are one of the major classes of pollutants found in fish. PFAS is persistent within the environment due to the strong carbon-fluorine bonds that make them resistant to degradation. Previous research has determined that exposure to relatively high concentrations of PFAS results in craniofacial malformations and reductions in foraging success. However, it is unclear whether exposure to environmentally relevant concentrations would result in similar craniofacial malformations, and whether this is correlated with impaired feeding. To address this, I will expose zebrafish larvae to 800 ng/L of PFOS or PFHxS for the first 5 days of embryonic development. A feeding assay will be performed with six-day old zebrafish larvae to determine the proportion of prey items they can capture. This will be correlated with assessment of the ultrastructure of the jaw and other potential malformations. Our findings will tell us about potential impacts on the foraging success of early larval fishes, which if reduced, could impact recruitment of fish, posing a risk to fish populations.

Exercise-Induced Extracellular Vesicle Effect on Immune Response

Major: Biology

Mentor: Dr. Jennifer Klein

Abstract: Macrophage immune cells play critical roles in the repair process of muscular damage resulting from exercise, especially heavy lifting. To accomplish this, macrophages will switch states, referred to as polarizations, changing their morphology, behavior, and surface marker expression. First, macrophages will polarize towards an inflammatory state to clear away debris from the injured tissue and inflame the area. Later, macrophages polarize to an anti-inflammatory state to initiate the healing process of the tissue that results in a larger and stronger muscle. Despite knowing that macrophages polarize towards these states during the muscular repair process, the agents that cause this change in macrophage behavior is not entirely known. One hypothesis is that lipid-enclosed packages of information known as extracellular vesicles (EVs) are released into the bloodstream from various cell types during exercise. EVs contain nucleic acids, proteins, and lipids and function as a form of cell-to-cell communication. EVs may also have a part in the changes that a body experiences as it ages, as individuals who exercise regularly have healthier immune system function; lower risk of developing autoimmune disease, cancer, and dementia; and a prolonged lifespan. To ascertain what changes in macrophage polarization may occur with exercise and increasing age, we have EV samples from volunteers taken before and after exercise and from various age groups. We exposed a human macrophage cell line to these EVs and measured their surface marker expression using flow cytometry and their morphological changes using DIC microscopy. This project aims to provide insight into the factors that cause declines in health with increasing age, particularly exercise.

xCT Regulation of Epstein-Barr Virus Reactivation: Insights into Mechanisms of Viral Control

Major:  Biochemistry

Mentor: Dr. Kelly Gorres

Abstract: The Epstein-Barr virus (EBV), one of the most common viruses in the world, is a member of the herpesvirus family and causes infectious mononucleosis (“mono”). Furthermore, EBV is associated with several cancers, including Burkitt lymphoma, nasopharyngeal cancer, and stomach cancer. EBV can reside in human cells for a lifetime in its inactive state, evading the immune system. When EBV is reactivated into its active cycle it can spread to other cells and cause symptoms and potential disease progression. Understanding the causes of EBV reactivation is important, as human host genes and proteins play a key role in EBV reactivation. To understand how EBV gets reactivated, this study investigated gene expression in EBV-infected human cancer cells treated with activators and inhibitors of EBV reactivation. Cells treated with inhibitors showed increased expression of the gene responsible for producing xCT, a protein that transports the amino acid, cystine, across cell membranes. xCT is known to regulate programmed cell death, a process, when disrupted, that can lead to tumor growth. Additionally, xCT reduces the amount of reactive oxygen species, which are known to induce EBV reactivation. These findings suggest that xCT could play a regulatory role in EBV reactivation. To investigate the significance of xCT in EBV reactivation, xCT protein expression was examined under conditions of promotion or suppression of EBV reactivation. Understanding how xCT influences EBV reactivation provides valuable insight into preventing reactivation and the development of possible treatments for EBV-associated cancers.

Behavioral Assessment of Carabid Beetles Hosting Laboulbenian Fungi

Major:  Biology

Mentor: Dr. Barrett Klein

Abstract: The Laboulbeniales are a poorly known group of microscopic fungi that associate only with arthropods (mainly insects) by attaching to their exoskeleton. Laboulbenian fungi are especially common in ground-dwelling beetles known as Carabidae. Yet, there remains a lack of understanding as to the behavioral impact these fungi have on carabid hosts. In this project, carabid beetles will be collected by hand from Myrick Park, scanned for infection, and then placed into individual 5.1 x 1.9 cm acrylic terraria. The Beetles (15 infected, 15 uninfected) will be given 24 hours to acclimate to a 12-h light 12-h dark cycle while being fed ad libitum. Each beetle will be analyzed after the acclimation period over three-days for the number and duration of self-grooming bouts using a Lorex security camera system, as well as for behavioral indications of sleeping. Their total food and water intake during the filming period will be tracked by weighing both nutrient sources before and after each day of feeding. After behavior has been fully assessed in each beetle, the fungal thalli from five infected beetles will be isolated and undergo DNA extraction for species specification and to test different extraction procedures. This study holds value in being the first to examine the relationship between the carabid beetles and Laboulbenian fungi from a behavioral perspective.

Synthesis of Novel Anti-Melanoma Drug, A-11

Major:  Chemistry

Mentor: Dr Aaron Monte

Abstract:The indigenous peoples of Wisconsin have long relied upon surrounding flora and fauna for medicinal and healing resources. For centuries, the Red Cliff Band of the Ojibwe Tribe have utilized leaves of the bushy shrub, Comptonia peregrina (“Sweet Fern”), as part of their traditional medicinal practices. Sweet Fern leaves have been used to line food-gathering baskets and applied to wounds to prevent infection. Working closely with Ojibwe faculty and student members, our research team acquired samples of this plant. A prior NSF-funded program identified a new molecule, CL-3, that showed anti-microbial activity versus Gram (+) bacterial growth and bacteria resistant to first-line antibiotics. An iterative synthetic-medicinal chemistry research program led to over 250 unique chemical entities. From this work, three compounds were discovered: SK-03-92, CL-5, and A-11. A-11 has been shown to significantly inhibit melanin production, indicating use as a skin-lightening agent. Studies showed A-11 is ~20,000 times more potent than arbutin, with less toxicity. Further studies found A-11 dramatically inhibits proliferation of melanoma tumour cells. A-11 tested in a transgenic zebrafish line reliably producing melanoma cancers showed inhibition of melanoma formation and recovery. Examining its mechanism of action showed A-11 to be more effective and less toxic than FDA-approved drugs cobimetinib and decarbazine. A-11 is a prime candidate for further pharmacological studies and potentially Phase I clinical trials. However, only a tiny amount was synthesized, insufficient for future studies. The main objective is to synthesize larger quantities using a refined synthetic scheme for higher yields and lower production costs. Successful completion will enable extensive R&D, mammalian studies, and preclinical evaluations. This may attract larger pharmaceutical companies to produce A-11 commercially and generate funds to advance research on its oncological properties and its potential as a future melanoma treatment.

Novel Species and Geographic Range Extensions in the Fungal Family Hygrophoraceae from Western North America

Major:  Biology - Master of Science 

Mentor: Dr. Arthur C. Grupe

Abstract: Fungi in the family Hygrophoraceae are widely known for their often vibrant coloration, diverse ecological roles, and conservation significance. Despite their showy nature, the extent of their global diversity has yet to be catalogued. Over the last 10 years, collaborative efforts between academic and community scientists have contributed extensive, high-quality vouchered collections and DNA sequences of members of this family. These contributions have extended known biogeographic ranges and elucidated phylogenetic relationships. This project highlights several species that are hypothesized to be new to science, particularly in Western North America. 

Optimizing electro-polymerization methods to create selective polymer co-catalysts for the CO2 reduction reaction.

Major:  Biochemistry

Mentor: Dr. Sujat Sen

Abstract: Carbon Dioxide (CO2) is abundant in our atmosphere, and its conversion to value added chemicals (such as ethylene) using renewable electricity is an active area of investigation. Previous research has shown that copper-based catalysts can aid in producing a wide range of hydrocarbons through the electrochemical reduction of CO2. Herein, I report on the synthesis of polypyrrole (PPy) thin films on the surface of copper. PPy is an important topic of research because it has the ability to conduct electricity and can also be modified to have different properties through traditional organic synthesis. When electrodeposited on solid copper, this polymer has a co-catalytic effect that can create selectivity and efficiency variations during CO2 conversion. I report on the use of electrochemical techniques such as cyclic voltammetry and chronoamperometry to deposit films of varying thicknesses and assess surface morphologies. Preliminary results show that varying the voltage used to create the polymer and the concentration of the monomer (pyrrole) create disparity in the superstructure of the polymer film. I also report on the use of various analytical techniques such as x-ray diffraction (XRD), scanning electron microscopy (SEM), and capacitance testing to characterize these thin film catalysts with respect to size, composition, and surface roughness, as well as preliminary tests on their performance as a catalyst for CO2 conversion. 

Truffles of the Midwest

Major:  M.Sc. in Biology

Mentor: Dr. Arthur C. Grupe

Abstract:  Truffle fungi are a cryptic yet charismatic group including genera with rich culinary and ecological histories. Because their sequestrate spore-forming bodies are often found below ground, their distribution ranges can be less well-documented than other macrofungi. While there is a strong record of truffle documentation in certain parts of North America, there is still a need to fill in sampling gaps. One such area that has been comparatively under-sampled for truffle fungi is the Upper Midwest region. We present here a summary of truffle fungal diversity data for this region. The genera Elaphomyces, Genea, Geopora, Hymenogaster, Pachyphlodes, Rhizopogon, and Tuber are included among others. Sources for this data include MycoPortal, GlobalFungi, Mushroom Observer, iNaturalist, and surveys with academic and community scientists. The results are presented here to convey the state of our knowledge and to dig deeper into any patterns that can be discerned in the data.

Influence of water temperature and dissolved oxygen on aquatic invertebrate emergence in Pool 8 of the Upper Mississippi River

Major:  Environmental Science with emphasis in Biology (BS)

Mentor: Dr. Ross Vander Vorste

Abstract: Aquatic insects are crucial organisms for maintaining freshwater ecosystem health as they contribute significantly to the decomposition of organic material and nutrient cycling (Malmqvist 2002). Juvenile stages are spent in aquatic habitats before emerging from the water as flying adult insects. Aquatic insects are highly sensitive to changes in their environment and are used as bioindicators for ecosystem health (Bonacina 2022). Water temperature and dissolved oxygen are known to influence insects in their juvenile and adult stages (Croijmans et al. 2021). Previous studies identified critical values of these environmental factors, triggering certain invertebrate species to emerge. For example, water temperatures ≥ 20ºC were noted for optimal emergence of mayflies on Lake Erie (Corkum et al. 2006). Increased temperature above this value can lead to pre-emergence and smaller-bodied insects, potentially reducing species fitness (Atkinson 1994 and Brown et al. 2010). Abundance and emergence patterns are negatively affected by dissolved oxygen below 8 mg/L (Voigt et al. 2023). While critical values of temperature and dissolved oxygen have been observed in some species, temperature-resistant species instead displayed typical body size during earlier emergence (Hogg and Williams 1996). Inconsistent results and a lack of standard monitoring in numerous river systems (Appel et al. 2019) highlight the need for more research. My project will examine the relationship between emergence patterns of aquatic invertebrate species collected in the Upper Mississippi River (UMR) with water temperature and dissolved oxygen. I hypothesize the highest rate of emergence will occur when water temperature reaches 25ºC with dissolved oxygen content above 8 mg/L, marking the optimal threshold. Other environmental factors may influence emergence, and this data will be collected as well. Determining optimal emergence thresholds improves understanding of insect species' responses to environmental change and better conclusions on the effects of warming climates through the study of these bioindicators’ emergence patterns.

Designing a Flexible Antenna Array to Enable IoT Solutions for Smart Farming in Wisconsin

Major:  Computer Engineering 

Mentor: Dr. Dipankar Mitra

Abstract: This research presents a low-cost, flexible antenna array designed to improve Internet of Things (IoT) connectivity for smart farming in Wisconsin. Prototyping includes the use of consumer-grade 3D printing to fabricate antennas with a conductive filament and flexible base. The elastic properties of the filament enable the antenna to be securely mounted on pipes, weather stations, or vehicle panels without compromising signal strength. Simulations were performed in CST to ensure optimal performance over a range of bending. The reduction in manufacturing costs and simplification of installation make it practical to deploy in outdoor conditions or hard-to-reach areas. In turn, farmers can utilize IoT devices, such as moisture sensors and pest-monitoring cameras, to enhance resource utilization and optimize yields. 

Structure, stability, and function of a Salmonella copper resistance protein with changes to a linker region

Major:  Biochemistry

Mentor: Dr. John May

Abstract: Copper ions are used in a variety of ways for their antimicrobial properties. However, bacteria can resist copper’s antimicrobial properties using several mechanisms. In Salmonella enterica, a protein named DcrB aids in copper resistance. Previous research indicates that mutating two residues in DcrB in a region that links a small N-terminal beta hairpin to its core structure results in altered stability, and decreased function of the protein. This change may be a result of the loss of a salt bridge involving this linker region of the protein. To investigate the role of this salt bridge, the interaction will be probed by designing a series of mutant variants and investigating their structure, stability, and function. Protein structure was investigated by circular dichroism, cross-linking assays, and protein crystallography. Stability was investigated by circular dichroism and differential scanning fluorimetry. Protein function was investigated by copper spot-dilution assay using S. enterica. Previous experimentation to probe the salt bridge was done using an N-terminal poly-histidine tag to purify the protein, however, future characterization will be done with a different tag which is not known to interact with metal ions. Identifying residues in the linker region of DcrB as a critical element of its functionality would provide a greater understanding of how the copper resistance protein works. This research was made possible by grants from UWL’s Undergraduate Research and Creativity program.

Occurance and Cooccurrence patterns of Mottled Sculpin and Slimy Sculpin in the Kickapoo River Drainage

Major:  Biology

Mentor: Dr. David Schumann

Abstract: Freshwater sculpins play important roles as both predators and prey in coldwater stream systems worldwide. Historically, Mottled Sculpin (Cottus bairdii) and Slimy Sculpin (Cottus cognatus) were abundant throughout Wisconsin Driftless Area streams. However, past land management practices altered these ecosystems and caused the extirpation of sculpin from the many coldwater streams. Some sculpin populations have since recovered in many streams from natural recolonization and reintroduction efforts. Due to their high sensitivity to environmental changes, sculpins are used as an indicator species of anthropogenic impact in stream systems. Despite their known importance, little is known about their basic ecology in the Wisconsin Driftless Area leaving knowledge gaps that could inform better management practices. Our goal is to gather an understanding of the occurrence and cooccurrence patterns of mottled and slimy sculpin within the Wisconsin Driftless Area to support future management and reintroduction efforts. We sampled 60 randomly selected cold and coolwater streams across the Kickapoo River Drainage. The allocation of streams to each watershed was based on areas where sculpins have been identified in previous WDNR stream surveys. Sampling reach lengths were determined by multiplying the mean stream wetted width by 35. Fish assemblages were sampled using backpack and barge electrofishing units with modified 3-pass depletion and single pass approaches. Instream habitat measurements were collected at three points along 15 equally spaced transects, measuring depth (mm), bottom and average current velocity (m/s), percent substrate embeddedness, and substrate composition. Additional observations and measurements of instream macrohabitat, water temperature (°C), riparian and streambank vegetation, streambank slope, and streambank substrate composition were collected at every transect. The information gathered from this study will describe mottled and slimy sculpin distributions, along with fish assemblage and habitat associations, providing valuable insight for future conservation and management efforts.

Engineering Nanofluids for electrochemical applications: Thermophysical properties of surface modified silica nanoparticle suspensions

Major: Chemistry

Mentor: Dr. Sujat Sen

Abstract: Colloidal suspensions of nano-sized particles (NP) in aqueous media have been historically investigated for their superior thermal properties. Multi-functional suspensions of nanosized particles (nanofluids) have also been investigated as catalytic media for chemical reactions, solar harvesting, and battery applications. Complex and novel behaviors exhibited by such fluids have resulted in theories proposed to explain their thermophysical properties such as viscosity and thermal conductivity, but their use in electrochemical systems remains relatively novel.  Here, we report on the use of silica-based NPs and their surface modification using functionalized silanes to prepare stable nanofluids in aqueous base fluids. Nanofluid preparation of both pristine and surface-modified NPs uses a temperature-controlled high-intensity horn sonicator, which uses ultrasonic waves to separate aggregates of NPs in solution. Particle size, morphology, grain size, colloidal stability and crystallinity of the nanoparticle were confirmed through various analytical methods such as electron microscopy (SEM), sedimentation tests, dynamic light scattering (DLS), and X-ray diffraction (XRD). Furthermore, we report on the surface modification, which aims to decrease the intermolecular attraction between individual NPs by introducing the silane graft. Grafts presence is expected to minimize the formation of aggregates after sonication and for the suspension to not settle under gravity over time.

Effects of Real-time Impact Force-based Augmented Feedback on Running Patterns of Novice Recreational Runners

Major:  Dual Degree Biology Pre-PT

Mentor: Dr. Thomas Kernozek

Abstract: Running related injuries may be related to excessive ground reaction forces (GRF). The study’s purpose was to see if participants could lower their peak GRF via concurrent augmented feedback while running on an instrumented treadmill. We examined healthy male and female novice runners ages 19-23. Retro-reflective markers were placed on fifty-four selected body segments. After a standardized warmup, running data were collected for baseline peak GRF to determine 5% and 10% reduction goals. They received concurrent augmented visual feedback while running to provide a visual representation of whether they were above or below their 5% and 10% peak GRF reduction goals. We removed the visual display and examined their short-term retention. Kinematics were measured with 3D motion capture and kinetics were measured on the instrumented treadmill. All data were compared from the stance phase of running. Statistical differences were obtained in the following variables for both the 5% and the 10% reduction goals: center of mass vertical excursion (decreased by 15%), hip extension moment (increased by 6.5% and 11.5%), knee extension moment (decreased by ≈11%), ankle plantarflexion moment (decreased by 8.3%), hip flexor extensor range of motion (increased by 4.3% and 6.4%), foot reach (increased by ≈16%), cadence (increased by 4.3%), peak vertical GRF (decreased by 9.5% and 11.7%), peak anterior posterior GRF braking (decreased by ≈12%), and peak anterior posterior GRF propulsion (decreased by ≈4%). Providing augmented feedback may be effective in reducing variables relevant to running related injury. This may be relevant in the rehabilitation of injured runners.

Impacts of Chronic Exposure to Environmentally Relevant Concentrations of PFAS on the Development and Growth of Zebrafish, Fathead minnow, Walleye, and Lake Sturgeon Larvae

Major:  Chemistry 

Mentor: Dr. Tisha King-Heiden 

Abstract: Per- and poly-fluoroalkyl substances (PFAS) are a group of synthetic organic chemicals that are present in many daily used products such as nonstick cookware, firefighting foam, makeup, and clothing. PFAS are known as “forever chemicals” due to their strong C-F bonds that are resistant to biodegradation, photolysis, hydrolysis, and photo-oxidation. They persist withing the environment and are found. Regulations from the Environmental Protection Agency (EPA) have been established, limit the amount of some PFAS in water systems. Recent studies have shown that PFAS are not only capable of affecting human health but also fishes. Most research examines Danio rerio (Zebrafish) larvae, observing that exposure to higher concentrations of PFAS impact developmental, survival, hatching success, behavioral, and neurological aspects. Little is understood with respect to the risks posed by exposure to environmentally-relevant concentrations of PFAS on fish development in ecologically-critical species. To address this data gap, we have exposed various species of fish to environmentally relevant concentrations (0, 0.8, 8, 80 or 800 ng/L) of PFOS or PFHxS, and assess effects on survival, hatching success, growth, inflation of the swim bladder and other developmental endpoints. Comparing common laboratory model species (zebrafish and fathead minnow) to wild-caught at-risk species (walleye and lake sturgeon) will help us better understand the risks that PFAS pose to the survival and recruitment of wild fish populations in our ecosystems. 

Does Rap1b Play a Role in Megakaryocyte Adhesion?

Major:  Clinical Laboratory Science

Mentor: Dr. Jaclyn Wisinski

Abstract: In bone marrow, hematopoietic stem cells differentiate into all blood cell types, including megakaryocytes, which are cells capable of producing platelets. During the process of differentiation, immature non-adherent megakaryocytes become adherent, increase in DNA content, and change in gene expression to accommodate platelet production. Adhesion is regulated by transmembrane proteins called integrins that attach to extracellular matrix proteins outside of the cell. The small signaling protein, Rap1b, plays a key role in platelet integrin activation. Maturing megakaryocytes increase production of proteins needed by platelets, such as the glycoprotein von Willebrand factor (vWF). We hypothesize that Rap1b signaling is important for many aspects of megakaryocyte maturation, including adhesion and expression of genes like vWF. To test our hypothesis, DAMI megakaryocytic cells with and without Rap1b were compared in adhesion assays and RNA quantification assays (termed qRT-PCR). To create DAMI cells without Rap1b, CRISPR/Cas9 was used to target and disrupt the Rap1b gene, resulting in cells with no functional Rap1b protein, termed DAMI ΔRap1b. If Rap1b is necessary for maturation, then DAMI ΔRap1b cells will be less adherent and have less vWF expression than wild type DAMI cells. This work adds to our fundamental understanding of how megakaryocytes mature into platelet-producing cells. 

Impact of β-hairpin interactions on the structure of the Salmonella copper resistance protein DcrB

Major:  Biochemsitry

Mentor: Dr. John May

Abstract: DcrB is a lipid-anchored protein expressed in a variety of Gram-negative bacteria, including a number that are known to be harmful to public health, such as Salmonella enterica. The DcrB protein is utilized by these bacteria in providing resistance to otherwise toxic concentrations of copper ions, which Salmonella may encounter in antimicrobial surfaces, CuSO4-treated agricultural land, and the immune systems of mammalian hosts. In previous experiments, DcrB has crystallized as a homodimer wherein an N-terminal β-hairpin of one dimer interacts with the hydrophobic core of the second dimer. This interaction is necessary for the protein to function in copper resistance, but the effects of β-hairpin modification on the protein as a whole are still largely unknown. Differential scanning fluorimetry, circular dichroism, and a cross-linking assay were utilized to compare Wild Type DcrB to DcrBΔ55, a non-functional mutant wherein the N-terminal β-hairpin is completely removed. These tests help to reveal the thermal stability, secondary, and quaternary structure of the protein. Investigating this mutant could help reveal the importance of the β-hairpin group in both the function and overall structure of the protein. These findings could aid in future efforts to understand copper resistance in Salmonella enterica and other pathogenic bacteria like it as well as help in the development of new antibiotics that can be used against them. 

Effect of the copper chelator, bathocuproine disulfonate (BCS), on SK-03-92 treated yeast cells

Major:  Biology with a concentration in Molecular Genetics and Cell Biology

Mentor: Dr. Anne Galbraith

Abstract: Pathogenic bacteria and fungi can become resistant to antimicrobial compounds, making it difficult to treat infections. Use of natural antimicrobials from plants has been a common practice dating back thousands of years, with an increased number of approved drugs from natural products in recent years. Researchers at UW- La Crosse and UW- Milwaukee derived a stilbenoid compound, SK-03-92, from Comptonia peregrina (sweet fern), which effectively kills several species of Gram-positive bacteria. However, the exact mechanism of action of SK-03-92 is unknown. Our lab showed that SK-03-92 affects the growth of Baker’s yeast (Saccharomyces cerevisiae), disrupting their mitochondrial morphology. Through a large-scale RNA sequence analysis done by our lab, copper homeostasis genes appeared to be dysregulated in cells treated with SK-03-92. We showed that bathocuproine disulfonate (BCS), a copper chelator, can ameliorate the effects of SK-03-92 on cell growth. In this work, BCS was used in conjunction with SK-03-92 to see if BCS also ameliorated the effects of SK-03-92 on mitochondria morphology. This project aimed to provide insight into the mechanism of action of SK-03-92 and other antimicrobials with similar stilbenoid structures. 

Effects of PFAS on the ability of larval fish to escape predation.

Major: Chemistry and Biochemistry, University of Wisconsin-Stevens Point

Mentor: Dr. Tisha King-Heiden

Abstract: PFAS (per- and polyfluoroalkyl substances) are a group of over 15,000 synthetic compounds used in thousands of everyday products and industrial applications.  Their resistance to degradation has resulted in ubiquitous contamination within aquatic ecosystems, and yet risks to wild fish populations remain unclear. Our previous work has shown that chronic exposure to environmentally relevant concentrations of two PFAS (PFOS and PFHxS) impair the startle reflex in zebrafish and fathead minnow larvae, indicating the potential to impact their ability to escape predation.  Here we test the hypothesis that chronic exposure to these PFAS will make these larvae more susceptible to predation. Preliminary findings suggest that fewer larval fish escape predation, and on-going studies will help us to better understand the risks that exposure to environmentally relevant concentrations of PFAS pose to wild fish populations.

Microplastic abundance in birds across varying trophic levels of the Upper Mississippi River

Major: M.S. General Biology 

Mentor: Dr. Eric A. Strauss and Dr. Markus Mika

Abstract: Microplastic pollution is of increasing environmental concern threatening various ecosystems and organisms. Microplastics are characterized as nonbiodegradable particles ranging from 250µm-5mm in size. To assess pollution levels in the environment, bioindicators or model organisms are useful to show exposure rates and the potential effects of pollutants on environmental and human health. Avian wildlife are good model organisms for microplastic analysis due to high mobility, their distribution across many trophic levels (categorization of organisms with similar diet composition), and as examples of biomagnification for pollutants. Plastic pollution poses numerous risks to birds, including entanglement with larger plastics resulting in suffocation, drowning, increased predation risk, along with reduced foraging and prey capture efficiency. The accidental ingestion of microplastics can lead to gut obstruction, ulcers, false satiety, and even direct mortality. Although microplastic research is increasing, a significant gap remains identifying where microplastics accumulate within the avian digestive tract and how species-specific accumulation varies with body mass and trophic position. Preliminary data shows that a total of 1338 microplastic particles were found in 83 bird digestive tracts (mean[range]=16.1[0-83] particles/bird). The results of this study will increase our knowledge of microplastic ingestion levels in avian wildlife and facilitate future research examining microplastic pollution in the environment.