Session D: 3:30PM – 5PM
Sciences. Session D – Poster Presentations, Ballroom, Union
SESSION D (3:30-5:00PM)
Location: Ballroom, A. Ray Olpin University Union
Fundamental Spectroscopic Studies of Transition Metal Nitrides and Carbides
Yexalen Barrera-Casas, University of Utah
Faculty Mentor: Michael Morse, University of Utah
SESSION D (3:30-5:00PM)
POSTER D53
The scientific exploration of the chemical bonds in transition metal nitrides (MN) is integral to a multitude of scientific fields. Some pertinent examples include the study of the Fe-Nitrogen bonds within the hemoglobin protein, electrochemical energy applications, and a deeper understanding of the complexities MN species demonstrate in organometallic chemistry. Although multiple studies have analyzed the general bonding mechanisms and schemes between transition metal and nitrogen atoms, there is a current lack of accurate and precise data on the fundamental bond dissociation energies (BDEs) for MN species. This shortage of thermochemical BDEs prevents the elucidation of quantitative and qualitative trends on the chemical bondings, electronic structures, and overall fundamental characteristics of MN species. Here, I present the predissociation thresholds of early and late 3d, 4d, and 5d MN species with the use of jet-cooled molecular beams through Resonant Two-Photon Ionization (R2PI) spectroscopy. The measured predissociation thresholds can be accurately assigned to the BDEs of the MN species studied within this work: D0(ScN) = 3.905 eV, D0(TiN) = 5.015 eV, D0(YN) = 4.125 eV, D0(MoN) = 5.220 eV, D0(RuN) = 4.905 eV, D0(RhN) = 3.659 eV, D0(HfN) = 5.374 eV, D0(OsN) = 5.732 eV, and D0(IrN) = 5.115 eV. The R2PI spectra resolve a dense manifold of molecular vibronic states at energies below the ground separated atom limit. When the MN species of interest is energetically excited to exactly the ground separated atom limit, the transition metal-nitrogen bond is broken and at energies above the predissociation threshold, a baseline of zero molecular signal is resolved. The electronic structures of the MN species can be put into context of these spectroscopically resolved thermochemical BDEs, allowing for the fundamental underpinnings of the chemical bond between transition metals and nitrogen to be illuminated.
Reactive oxygen species and methamphetamine effects on nucleus accumbens circuitry
Matthew Burris, Brigham Young University
Faculty Mentor: Jordan Yorgason, Brigham Young University
SESSION D (3:30-5:00PM)
POSTER D54
The nucleus accumbens (NAc) underlies many aspects of motivational behavior, including encoding methamphetamine reward seeking behavior. NAc circuitry is regulated by numerous excitatory and inhibitory distal and local inputs, with increasing evidence supporting a regulatory role by local microglia. Microglia are the immune cells of the brain and microglia are sensitive to ligands known to affect dopamine release, including reactive oxygen species, Nitric oxide (NO), Glutamate and lipopolysaccharide (LPS) (among others). Microglia change their morphology in response to these signaling molecules which is indicative of microglia activation levels. Microglia are diverse across brain regions and how NAc microglia surveillance (i.e., ramification) relates to dopamine terminal activity and interactions with methamphetamine are unknown. The current project examines microglia morphology and dopamine terminal activity and the effects of reactive oxygen species and methamphetamine. Methamphetamine is known to increase reactive oxygen species, which play a role in neurotransmitter release in the NAc. In order to investigate methamphetamine and reactive oxygen species effects on this circuit we took mice and followed a behavioral protocol known to cause methamphetamine locomotor sensitization. We also used a control group which were only given saline. These two groups were then used to measure inherent microglia morphology changes due to repeated methamphetamine injections. Additionally, these mice were used to look at responsivity of dopamine terminals to reactive oxygen species through dopamine and ATP release measured by fast scan cyclic voltammetry. We also looked at morphology changes of microglia from acute application of glucose oxidase, which is known to increase reactive oxygen species. Through investigations of this circuit, we can better understand how reactive oxygen species and methamphetamine affect dopamine terminals as well as microglia activity.
Taxonomic Verification of Southern Utah Bombus by of use COI sequence digestion and gel separation
Jake Olvera, Southern Utah University
Isaac Sorensen, Southern Utah University
Faculty Mentor: Jacqualine Grant, Southern Utah University
SESSION D (3:30-5:00PM)
POSTER D55
Bumblebees serve an important role as pollinators and many species are in decline. Effective conservation efforts rely on accurate species identifications which can be difficult because of morphological similarities among species. Southern Utah is home to many species – including Bombus morrisoni and Bombus nevadensis, which are challenging to morphologically differentiate despite being in different subgenera. These species may be inadequately represented in Southern Utah and other databases due to their ease of misidentification. To solve this problem of misidentification, we examined COI DNA barcodes to determine if unique restriction enzyme sites could be used to differentiate the two species. We found at least 9 unique restriction enzyme sites that could be used to distinguish Bombus morrisoni from Bombus nevadensis. Our results can be used to provide a reliable method for differentiating these two species, especially in areas where morphologically similar variants coexist.
The First SNAP Surface Brightness Fluctuation Distances
Mikaela Cowles, Utah Valley University
Faculty Mentor: Joseph Jensen, Utah Valley University
SESSION D (3:30-5:00PM)
POSTER D56
We have successfully acquired F110W (J-band) images of 68 massive elliptical galaxies in clusters and groups out to 80 Mpc by taking advantage of the efficient Hubble Space Telescope SNAP observing mode. We used the Surface Brightness Fluctuation (SBF) technique to measure distances to 44 of the galaxies so far with a typical uncertainty of ~5% in distance by implementing a new Python-based pipeline to simplify and automate the SBF analysis procedure. This new SNAP sample doubles the total number of IR SBF distances to galaxies beyond 50 Mpc. The new distances will allow for more accurate determination of the mass distribution in the local universe when combined with the Cosmicflows-4 database (Tully et al. 2022, arXiv:2209.11238). It will also provide a more precise comparison between early-type population distance indicators and distances derived from late-type galaxies via Cepheids well into the Hubble flow. These data will be combined with existing HST SBF distance measurements (Jensen et al. 2021, ApJS, 255, 21; Blakeslee et al. 2021, ApJ, 911, 65) to reduce the uncertainties in the local measurement of the Hubble Constant, which is currently at odds with the determination of the expansion rate at cosmological distances derived from cosmic microwave background fluctuations.
Environmental factors have little influence on drosophilid genome size.
Samantha Curnow, Utah Valley University
Faculty Mentor: Carl Hjelmen, Utah Valley University
SESSION D (3:30-5:00PM)
POSTER D57
The amount of nuclear DNA, or genome size, varies widely across the insect tree of life with no clear relationship with organismal complexity. Some insects have only 100 million base pairs, while others reach nearly 18 billion base pairs. Many hypotheses have been proposed to explain this genomic variation. Some suggest relationships to environmental adaptations, while others suggest size is driven by effective population size. To date, no single hypothesis clearly explains the genome size variation observed. In order to investigate these hypotheses, we utilize data from nearly 150 drosophilid species. With over a century’s worth of research on their genomes, life history characteristics, and behaviors, there is no shortage of available data for these organisms. We mined data from peer-reviewed papers and publicly available datasets pertaining to genome size, thermal limits, climatic variables, geographic location, haploid chromosome number, and a variety of other life-history characteristics. We then investigated the relationship of genome size to these variables using linear regression models and comparative phylogenetic analyses in R. Early work has found that while there is some relationship between genome size and climatic variables, much of these relationships are nullified when accounting for evolutionary relatedness. Since this early work, we have greatly expanded our dataset and explanatory variables. We present here the more complete and informative models of these relationships using this newly obtained data. With expanded data, we found no significant relationship between climatic variables and genome size. Future research may reveal relationships between environmental factors and genome size if running similar analyses with other groups of insects or if other variable data is published (i.e., humidity).
Placket-Burman Optimization of KAl(SO4)2
Emily Hiatt, Weber State University
Faculty Mentor: Brandon Burnett, Weber State University
SESSION D (3:30-5:00PM)
POSTER D58
KAl(SO4)2 crystals were synthesized and analyzed using Plackett – Burman Optimization, comparing the success of crystallization between viscosity, temperature, and concentration. The Plackett-Burman optimization is used for analyzing a few variables with reproducibility without having a massive amount of trials. Adapting this to experimentation and the lab is difficult, given the lack of technology available to make it accessible. For our experimentation, KAl(SO4)2 synthesis was manipulated in three ways – viscosity (water, propyl glycol, and glycerine), temperature (5C, 22C, and 45C), and concentration (0.2, 0.4, 0.6 g/mL). After a week of crystallization, the middle values of each variable performed the best and had the most measurable crystals. All crystals were measured with an optical microscope for size, and with x-ray diffraction for crystallinity. In order to make Plackett-Burman accessible, a program has been developed to automatically create the trials necessary to run any experiment necessary.
How big game animal’s hair structure helps them thermoregulate
Taylor Millett, Utah Tech University
Faculty Mentor: Samuel Tobler, Utah Tech University
SESSION D (3:30-5:00PM)
POSTER D59
The Pronghorn antelope is an animal known to have hollow hair strands among hunters and conservationists yet no one seems to know what it actually looks like on the inside. In this study, we examined what a hollow hair strand looks like under a microscope and how it helps with an animal’s thermoregulation. Thermoregulation is the ability to regulate body temperature within a livable range even when external temperatures fluctuate. We studied animals like Mule deer, Rocky Mountain elk, and Pronghorn antelope, as well as other big game animals, as they exhibit this trait in a unique manner. These animals have an adaptation more commonly known as a summer coat and a winter coat. Using a scanning electron microscope, we measured and compared an animal’s winter coat and summer coat to indicate why an animal can regulate body temperature through hot summers and cold winters. These coats of fur/hair change in thickness and length with the change of seasons. Under the microscope, we identified the different topography of the inner structure of a single hair strand. We found that the inner structure has hollow pockets in the winter coats of these animals. We then focused on the heat transfer of each individual hair and how this allows the animal to thermoregulate.
The M.A.C.H. System
Ricks Ricks, Utah Valley University
Faculty Mentor: Michael Rotter, Utah Valley University
SESSION D (3:30-5:00PM)
POSTER D60
Food insecurity is an important global challenge. As of 2020, around 282 million people in Africa suffered hunger due to this same food insecurity. We are faced with a problem that requires new techniques that can help to improve existing small scale farming. Enter the MACH system (Manageable Accelerated Community Horticulture), a mechanism that may provide a solution to communal horticulture and affordable small-scale farming. This system utilizes the elements of photosynthesis and magnifies those variables to generate produce at a much faster, and potentially larger rate. By filtering out harmful rays from the sun (namely infrared and ultraviolet), providing optimal climate conditions, and introducing supplemented concentrations of CO2 within an enclosed environment, it may be entirely possible to create a reliable source of local produce for members of a community without breaking the bank practicing traditional farming methods. Our main objective with this technology is to provide several solutions at an affordable cost of production, low maintenance, and simple upkeep and attention from its caretaker. To achieve this requires interdisciplinary cooperation with our engineering students and faculty to both test the results of the plant’s growth and develop the technology for the climate control system. With the success of this technology, we may be able to revolutionize the way that we do local farming, and may even shape the future of agricultural practices worldwide.
Investigating the role of a charge-charge interface in chromosome pairing
Jesus Aguayo, University of Utah
Faculty Mentor: Ofer Rog, University of Utah
SESSION D (3:30-5:00PM)
POSTER D61
Meiosis is a specialized cell division process whereby gametes arise in preparation for fertilization. Exploring the meiotic process has shed light on mankind’s understanding of the natural biological processes from reproduction to genetic engineering. The Synaptonemal Complex is a structure that forms during meiosis. This structure orients and aligns the two parental chromosomes which then allows for genetic exchange between them. Once germ cells have undergone meiosis, they are ready for the fertilization process which then results in offspring in ideal circumstances. Additionally, the SC allows for a precise number of gene exchanges between each set of chromosomes. Without the SC, there would be errors in the sets of chromosomes in a cell, reduced number of offspring, infertility, and more.
The SC is a highly conserved structure that is found in simple sexual reproducing organisms as well as complex multicellular organisms such as humans. If the SC were better understood, the quality of life of humans could be improved. Whether it’s helping an infertile individual receive treatment to be able to reproduce or to better understand conditions that result from aneuploidy in humans and other creatures, it’s undeniable that researching the SC is worthwhile. Using CRISPR/Cas9 technology, progeny and male count methods, immunofluorescent staining, and confocal imaging, I was able to obtain insights as to how the SC functions within the nematode Caenorhabditis elegans. Specifically, I focused on conditions that suppress a temperature sensitive mutation, syp-1 K42E. The data from progeny counts indicates that mutating certain specific proteins within the SC (syp-3 D62V, syp-3 D62N, and syp-4 E90K) can suppress the temperature sensitive mutation when they are each found in the same SC structure as the syp-1 K42E strain but they are unable to significantly cause any change when the temperature sensitive mutation is not present in the same structure. Immunofluorescent imaging also indicated that there was no significant difference between the suppressor strains and the wildtype strain. The findings from testing the individual strains without the suppressor strain gave insight as to the importance of charged interactions between the proteins within the SC. Since Lysine (K) was replaced by Glutamic acid (E) in the SYP-1 K42E protein, there was a significant difference between the wildtype C. elegans strain and the syp-1 K42E strain. However, the suppressor proteins were able to restore the phenotype of the C. elegans that had both the suppressor protein and the SYP-1 K42E protein.
Creation and Characterization of Electropolymerized Organic Mixed Ionic-Electronic Conductors
Arnel Besic, University of Utah
Faculty Mentor: Connor Bischak, University of Utah
SESSION D (3:30-5:00PM)
POSTER D62
Organic mixed ionic electronic conductors (OMIECs) are conjugated polymer systems that conduct both ions and electrons. They are promising materials for biosensors, neuromorphic computing platforms, and energy storage devices. An obstacle for these new materials is the lack of understanding of the fundamental processes that underlie operation, namely the coupled dynamics of ion motion, electron transport, and structural changes. This work presents the electropolymerization and characterization of thiophene-based polymers and copolymers. One advantage of electropolymerized materials is that they do not require bulky side chains to dissolve in organic solvents, allowing them to hold more charge per volume. Using electropolymerization, we synthesize several polythiophenes with different side chain chemistries. We investigate ion injection kinetics in these materials using spectroelectrochemistry and find that injection kinetics depend on the identity of the electrolyte. We also characterize their morphology with atomic force microscopy (AFM) and scanning electron microscopy (SEM). Electropolymerized OMIECs may play an important role in the advancement of OMIEC-based technologies due to their unique morphologies and ease of synthesis.
Carbon isotopic variability in paleosols and its effects on reconstructing pCO2: insights from the Upper Triassic Chinle Formation
Aiden Beukema, University of Utah
Faculty Mentor: Randall Irmis, University of Utah
SESSION D (3:30-5:00PM)
POSTER D63
Carbon isotope values from paleosols are an important proxy for atmospheric pCO2, providing clues to deep time paleoclimate. In modern soils, δ13Ccarb values typically reach equilibrium between 30-50 cm depth from the top of the soil profile (usually in the B horizon), so workers have assumed this to be true for paleosols as well. As a result, most paleosol carbonate pCO2 proxy data derive from point samples taken from the B horizon. However, few paleosol studies have examined the variability of δ13C down profile and within a single sampling horizon. Therefore, it is unclear whether taking a point sample at or below 50 cm is sufficient to recover the isotopic value at equilibrium for every paleosol, and how this sampling strategy affects subsequent reconstructed pCO2 values.
To investigate this problem further, we sampled calcic paleosols from the upper Chinle Formation of southeastern Utah, sampling every 10 cm along the soil profile. Multiple carbonate nodules were taken from each depth and were analyzed for δ13Ccarb and δ18Ocarb. Mudstone matrix from each depth was also analyzed for δ13Corg. Down-profile δ13Ccarb values rarely fit well to a theoretical vertical slope representing equilibrium, with variation of up to -3.6‰, often below the 50 cm depth. At any single sampling horizon within a paleosol, we observe variation of up to -4‰ between individual carbonate nodule δ13Ccarb values. This range of variation can significantly affect the pCO2 estimations; a difference of -4‰ in δ13Ccarb values (assuming the same δ13Corg value) can result in up to ~3605.4 ppm difference in reconstructed pCO2. Thus, we suggest that characterization of down-profile and within-horizon variability is critical for obtaining more accurate atmospheric pCO2 values from paleosols.
Exploring species boundaries in a widespread army ant genus using DNA barcodes
Megan DuVal, University of Utah
Faculty Mentor: John Longino, University of Utah
SESSION D (3:30-5:00PM)
POSTER D64
Army ants (Hymenoptera: Formicidae: Dorylinae) are keystone predators throughout most of the tropical and subtropical regions of the world. One of the most wide-ranging and ecologically important army ant genera is Labidus, which has a broad dietary niche and often high local abundance in the Neotropical region. Labidus taxonomy at the species level is in need of revision. Currently, seven valid species are recognized based on the morphology of workers and/or males, but little information on cryptic species within or phylogenetic relationships among them is available. Here, we attempt to define species boundaries within the genus by reconstructing its phylogeny using DNA “barcodes” (a segment of the mitochondrial COI gene) from 2,513 specimens, ultra-conserved element (UCE) data from six Labidus specimens plus two outgroup taxa, and COI barcodes extracted from UCE contigs. Phylogenies were reconstructed with Maximum Likelihood analyses, and based on a reconstructed UCE topology, a constraint tree topology was obtained with 74 specimens. Our analyses revealed at least seven COI clusters, with three of the species mainly characterized by the worker caste corresponding to multiple putative cryptic species. Our phylogeny also allowed us to associate two species known only from males with their respective workers. With the addition of more UCE data, morphological data, and species delimitation analyses, a reliable updated taxonomy of Labidus will emerge.
Detecting Black Holes in Omega Centauri
Zack Freeman, University of Utah
Faculty Mentor: Anil Seth, University of Utah
SESSION D (3:30-5:00PM)
POSTER D65
My project focuses on trying to detect some of the thousands of stellar mass black holes suspected to be present at the center of Omega Centauri through gravitational lensing. Omega Cen is the most massive globular cluster in the Milky Way, therefore making it a good candidate for detection of stellar mass black holes. Past studies have shown the need for a single Intermediate Mass Black Hole (IMBH) at the center of this cluster (e.g. Noyola et al., 2010), although more recent studies have disputed this claim. Instead, Baumgardt et al. (2019) favors the presence of a cluster of stellar mass black holes near the center of Omega Cen; so far, there is no direct evidence for even a single black hole. Omega Cen is a calibration target for the Hubble Space Telescope, and thus there is extensive imaging taken over the last 12 years. Within a single filter centered at 606 nanometers, this dataset provides about 160,000 stars with more than 100 measurements (an entire set of measurements for one star is called a lightcurve). Within these lightcurves, I am searching for a microlensing event caused by a stellar mass black hole. When a black hole (the lens) is lined up between us (the observer) and a star (the source), it causes an increase in the star’s brightness; this is the microlensing event I am searching for. My work this far has been modeling the lightcurves, including testing using synthetic microlensing events that I inserted into the data. I present a first search for potential events in this data.
Raman Spectroscopy Characterization of Antibody-Ligand Association at Supported Phospholipid Bilayers
Clista Galecki, University of Utah
Faculty Mentor: Joel Harris, University of Utah
SESSION D (3:30-5:00PM)
POSTER D66
There are fundamental questions about the chemistry of antibody-ligand interactions, Antibodies are proteins generated by the immune response to target pathogens through their specific binding to proteins or other ligands on cell membranes. One of the fundamental questions that is being addressed in this research is to determine how the accessibility of ligands at supported-lipid bilayers (models of cell membranes) varies with ligand coverage, thereby impacting their association with antibodies in solution. We detect the binding of proteins by measuring inelastic light scattering from their characteristic molecular vibrations using Raman microscopy. The use of Raman spectroscopy allows label-free and quantitative analysis of antibody-to-ligand binding. We are able to determine the concentration of antibody that has accumulated on the surfaces of supported-lipid bilayers. Unlike current methodologies, Raman spectroscopy can detect changes in the binding state of the targeted ligand. Understanding the binding state is crucial in assessing how ligand accessibility may influence its interaction with solution-phase proteins. We prepare lipid bilayers on the interior surfaces of porous silica particles, whose high surface area provides a sufficiently high concentration of both ligand and its antibody to allow detection of quite modest mol-fractions (2-mol%) of ligand-modified (2,4-dinitrophenylated) lipid. Capture of antibodies requires the presence of ligand in the bilayer, where lipid bilayers prepared without dinitrophenylated-lipid produce no detectable signal from the antibody. By varying the dinitrophenylated-lipid density, the surface concentration of captured antibody increases proportionally to a level that is limited by antibody size and packing density of antibody at the lipid-bilayer surface. After establishing specific protein accumulation and detectable changes in ligand state following binding, we plan to determine how the coverage of antibody impacts the binding state of the recognition ligands at supported lipid-bilayer interfaces and determine the stoichiometry of ligand-to-antibody binding.
Coinfection of Malaria and Gammaherpesvirus
Erin Garzella, University of Utah
Faculty Mentor: Tracey Lamb, University of Utah
SESSION D (3:30-5:00PM)
POSTER 67
Malaria kills more than 400,000 people a year. 67% of those deaths are children under five. Some children get malaria, but they do not die. The reasons for this are not completely understood. Malaria is caused by the Plasmodium parasite, in particular Plasmodium falciparum. Co-infection of malaria with gammaherpesviruses, such as Epstein Barr Virus (EBV), is common in young children under five in countries where malaria is present. Data from children living in Cameroon in Central Africa shows that children who have EBV and malaria are more likely to be hospitalized due to malaria complications than children who do not have EBV. Antibodies are one of the main weapons the immune system uses to fight malaria. EBV antagonizes antibody production, possibly by induction of IL-10, a molecule that prevents B cells from producing antibodies. EBV induces IL-10 production in infected cells and can synthesize a homolog of IL-10. We hypothesize that the IL-10 induced during EBV infection results in lower antibody titres in children who are infected with both the virus and Plasmodium parasites that cause malaria. The first goal of this research is to identify which cell types produce IL-10. VertX reporter mice will be used to determine this in a mouse model of EBV-malaria co-infection. Once specific cell types are identified genetically modified mice will be used to observe what happens during co-infection when those cell types have the IL-10 gene knocked out.
The Cause of Excess Magmatism in the Northern Atlantic Margin
Autumn Hartley, University of Utah
Faculty Mentor: Emily Cunningham, University of Utah
SESSION D (3:30-5:00PM)
POSTER D68
Excess magmatism is a common occurrence near areas of tectonic rifting, but a region off the coast of Norway was found to have a much greater degree of magmatism than typical circumstance permits. To investigate the cause of this excess magmatism, the International Ocean Discovery Program (IODP) launched Expedition 396 to take drill core samples from ocean floor basalts that erupted about 56 million years ago. There are three leading hypotheses for the source of excess magmatism in the Northern Atlantic: a thermal anomaly caused by an interaction with the Icelandic mantle plume, small-scale convection at the base of the lithosphere, heterogeneities in the mantle source, or a combination of all three. Through the use of thermobarometry (Lee et al. 2009), we have determined that a thermal anomaly was present at the time of emplacement. However, it is not the sole contributor to the sheer amount of erupted material present. As such, we have begun our investigation into the other two hypotheses by modifying the excel software package Melt-PX (Lambart et al. 2016) to model an active upwelling region and analyzing samples to determine what role convection and composition play in this system.
References:
Lambart, S., Baker, M. B., Stolper, E. M., (2016). The role of pyroxenite in basalt genesis: Melt‐PX, a melting parameterization for mantle pyroxenites between 0.9 and 5 GPa: Journal of Geophysical Research: Solid Earth, 121(8), 5708-5735. doi: 10.1002/ 2015JB012762.
Lee, C., Luffi, P., Plank, T., Dalton, H., Leeman, W. (2009). Constraints on the depths and temperatures of basaltic magma generation on Earth and other terrestrial planets using new thermobarometers for mafic magmas. Earth and Planetary Science Letters, 279(1-2), 20-33. 10.1016/j.epsl.2008.12.020
Reconstruction of fire and vegetation history by analysis of charcoal morphometrics from known Utah plants
Amy Harvey, University of Utah
Faculty Mentor: Stella Mosher, University of Utah
SESSION D (3:30-5:00PM)
POSTER D69
Fire is one of the major forces that influences vegetation type and ecosystem dynamics of an area. Reconstructing past fire regimes can help us understand not only about the type of plants that were once in an area and how they responded to fire, but also how best resource and landscape management practices can be employed to preserve present ecosystems under a changing climate. This research contributes to the reconstruction of a mid-Holocene fire record from Verlorenvlei, South Africa, a dry west coast site in South Africa’s Fynbos biome. The paleofire reconstruction provides insight into fire frequency, fire intensity, and fuel type, and the study of charcoal morphology (the shape of the particles) and morphometry (length:width ratio of the particles) is a method used to determine the types of vegetation that were burned. In this project, the morphometric analysis of macroscopic charcoal particles from lake sediments in tandem with the analysis of charcoal particles collected from experimental burning of modern plant reference material was used to understand vegetation change around Verlorenvlei, and may shed light on other metrics of interest to the paleofire community, such as wildfire temperature and intensity. Work is underway to experimentally burn fynbos vegetation at the Natural History Museum of Utah.This research adds to a developing body of work exploring charcoal morphometry and fire history in South Africa, and will be compared to charcoal morphometrics from a more humid and wet portion of South Africa’s Fynbos biome along the southern coast. Together, these findings will help us understand how the vast diversity of plants in South Africa’s Fynbos biome is reflected in the charcoal record.
Understanding the Multifaceted Nature of the pasTI Toxin-Antitoxin System
Sam Hendry, University of Utah
Faculty Mentor: Mathew Mulvey, University of Utah
SESSION D (3:30-5:00PM)
POSTER D70
Toxin-Antitoxin (TA) systems are common bipartite operons in prokaryotes. TA systems are composed of two genes adjacent to one another in which one encodes a protein toxic to the bacteria while the later provides the antitoxin. While TA systems are not well understood they have been implicated in phage resistance, biofilm production and persister cell formation which helps bacteria survive antibiotics and cause recurrent infection. One such system, PasTI, has been shown to be important for Extraintestinal pathogenic Escherichia coli (ExPEC) survival in the kidney and bladder and promotes the formation of persister cells when exposed to antibiotics. To better understand the pasTI system, strains lacking the TA operon were grown under oxidative and nitrosative stress conditions and shown to respond significantly worse than wild-type E. coli. Additionally pasT clones from other bacterial species with different pasT N-termini sequences: Y. pestis and N. meningitidis, were generated. When expression of PasT was induced in these clones and the wild-type, only the wild-type pasT proved to be toxic to the cell. Meanwhile, the clones continued to grow to an equal or better level than the wild-type. The clones also responded to stress conditions to equal or greater than wild-type abilities. Together the results suggest that the pasTI TA system plays a role in bacterial persistence and stress response and that the toxic effects observed in E. coli are the result of the N-terminal domain of the protein while differences in this protein region appear to relieve the toxicity of PasT while maintaining persistance and stress resistance abilities. The PasT protein’s ability to aid in stress response and persistance could make it a target for antibiotic therapies against ExPEC and other pathogenic prokarya that have the gene.
The identification and characterization of an autosomal gene that works in association with Overdrive to create hybrid incompatibility within Drosophila pseudoobscura subspecies.
Caroline Keller, University of Utah
Faculty Mentor: Nitin Phadnis, University of Utah
SESSION D (3:30-5:00PM)
POSTER D71
The evolution of reproductive barriers is essential for speciation – the process by which one species splits into two. One of the fastest barriers to evolve between species is the sterility of hybrid males. With a speciation event of 175,000 years ago, the USA and Bogota subspecies of the fruit fly Drosophila pseudoobscura are among the youngest pair of species to be studied genetically. Crosses between Bogota females and USA males results in sterile hybrid males. Rarely, these hybrid males are able to produce offspring, but when they are successful all offspring are female, a process known as sex-ratio distortion. The hybrid incompatibility system of Drosophila pseudoobscura is the premier system to study the role of selfish genetic elements such as segregation distortion in the evolution of new species. The genetic architecture underlying both sterility and segregation distortion in this system is complex. One of these components has been identified so far – Overdrive (Ovd), located on the X chromosome of Bogota is required for both sterility and distortion. Ovd, however, has no effect on its own and requires an interaction with a dominant autosomal gene. Previous mapping suggests that this gene, whose interaction with Ovd is essential for both hybrid phenomena, is located on the second chromosome of USA. My goal is to identify this autosomal factor using an approach that combines an X-ray mutagenesis screen with whole genome sequencing. Identification of this final component of the Drosophila pseudoobscura hybrid incompatibility system will provide key information on the genes underlying segregation distorters and hybrid sterility between species, and open the door to understanding molecular mechanisms of selfish genes.
Dalekin Signaling: Genetic Analysis of Suppressors
Haylee Mathews, University of Utah
Faculty Mentor: Leslie Sieburth, University of Utah
SESSION D (3:30-5:00PM)
POSTER D72
Dalekin is a novel plant hormone that is made in the plant roots; it moves through the plant to signal the perception of drought and salt stress. These stresses are known to repress growth, and dalekin does this by repressing WUS expression (which is necessary for shoot stem cells that allow for plant growth). Because dalekin is over-produced in bps1 mutants, the loss-of-function bps1 mutant is believed to normally function to regulate the synthesis of dalekin. The phenotype that results from the excess of dalekin in bps1 mutants is that both shoots and roots are highly abnormal. However, a cold-sensitive suppressed line was isolated after bps1 was crossed to a different accession (Apost-1). These plants, which we call Red4A bps1, produce normal-looking shoots and roots that are somewhat short and highly branched when grown at warm temperatures. Because drought stress is an urgent problem, my project is to identify additional genes that function through dalekin signaling. To identify genes that function in dalekin synthesis or response, I am characterizing suppressor mutants. Mutagenesis was carried out using Red4A bps1 seeds, and the mutagenized seeds were grown at warm temperatures to collect self-pollinated seedlings. The resulting self-pollinated seeds were then grown at the restrictive temperature (16˚C), and suppressors (called RT lines) were identified because they, but not the parental Red4A bps1, were able to flower and set seeds. My goal is to identify one of the genes that, when mutated, allowed bps1 suppression. Identifying suppressor genes will help us understand the dalekin signaling and biosynthesis pathway. Because mutagenesis leads to many mutations across the genome, the RT lines were then backcrossed to Red4A bps1, F1 seeds were grown and allowed to self-pollinate, and F2 seeds recovered. The F2 seeds are homozygous for bps1 but segregate for the RT suppressor. I am currently characterizing the phenotypes and segregation ratios of the
Natural Variability of the Pre-Aksumite Afromontane: a control for deforestation analysis
Corinna McMurtrey, University of Utah
Faculty Mentor: Mitchell Power, University of Utah
SESSION D (3:30-5:00PM)
POSTER D73
The Aksumite Empire was a prosperous African civilization that thrived on the Tigray Plateau in modern-day Ethiopia between c. 50 BCE and 700 CE. Their advanced agriculture techniques and fertile volcanic soils aided in productive yields able to support their population. Located on the East African Rift Zone, the Tigray Plateau was formed from ancient volcanic activity. Because of this geologic history, the deposition of volcanic ash provided a resource that ultimately improved soil quality for agricultural use. However, volcanic activity can also produce short-term climate changes that severely hinder agricultural activities. As the impact of volcanism on the Aksumite Empire has yet to be explored, my proposed Undergraduate Research Opportunity aims to understand the impact of volcanism on the Aksumite Empire’s agricultural production and if volcanic activity played a role in their ultimate collapse. This research will be conducted by processing and analyzing sediment samples previously collected from a valley system near the modern town of Adigrat, on the Tigray Plateau, Ethiopia. These sediment samples will be analyzed using X-ray fluorescence (XRF), which can detect and measure most soil elements providing insight on mineralogical content, including elements that will aid in identifying periods of volcanic ash or tephra fallout. This research will also explore the evidence of fire activity from charcoal analysis of sediment samples to examine potential links among climate, fire, volcanism, and agriculture. Although fire may be both natural and human-caused, this analysis will provide an opportunity to explore if fire was used as tool during Aksumite agricultural production.
Calibrating the Scanning Mobility Particle Sizer
Angelina Miller, University of Utah
Faculty Mentor: Gannet Hallar, University of Utah
SESSION D (3:30-5:00PM)
POSTER D74
Small particles suspended in the air called aerosols play important roles in radiative forcing and human health, but there is still much that is unknown about the net effect of aerosols on environmental interactions and how those will play into future climate models. In order to better understand where our earth is heading, and possibly plan for ways to mitigate this change, we need to learn more about these versatile nano-particles, how they form, and what else they can affect. One instrument used to do this is the sizing mobility particle scanner (SMPS). The SMPS measures particle size and concentrations for particles between roughly 8.51nm and 461.4nm, but its measurements can drift over time. The University of Utah has a SMPS on the top of the William Browning Building, and it is essential that this data is accurate, organized, and easy to work with so that it can be used to better understand the makeup of our atmosphere in the Salt Lake Valley. To ensure the accuracy of the measurements from the SMPS, a manual calibration and analysis of the instrument is needed to adjust for any uncertainties. Calibrations are run by running polystyrene latex micro-beads through an atomizer and into the SMPS so that any shift in the instrument’s baseline can be adjusted to match the peak particle size reading with the expected value corresponding to the bead size. For future calibrations, this process will be repeated with multiple different sizes of microbeads and finally without any added microbeads so that a statistical analysis of the data received can be completed. These calibrations will ensure that any unexpected readings are adjusted so that future and past measurements by this instrument can be validated.
Development meets Metabolism: Investigating how Diet and Nutrition Influence Developmental Decisions
Samantha Nestel, University of Utah
Faculty Mentor: Michael Werner, University of Utah
SESSION D (3:30-5:00PM)
POSTER D75
The effect of the environment on development is critical to human health, and animal and plant ecological strategies. However, the molecular mechanisms that regulate developmental (phenotypic) plasticity remain poorly understood. When exposed to different environments, the nematode Pristionchus pacificus expresses one of two possible mouth forms: either the ‘Stenostomatous’ morph with a narrow buccal cavity and one tooth-like denticle, or the ‘Eurystomatous’ morph that has a wide buccal cavity and two teeth-like denticles. In my project, I have been assessing whether morph choice, an experimentally tractable example of developmental plasticity, is mediated by nutrition. Specifically, I performed two experiments to test the putative connection between nutritional status and phenotype: 1) grew and collected P. pacificus on different environments – poor and rich nutrition – for metabolomic analysis and 2) conducted dietary restriction experiments with different Pristionchus species to assess the generality and conservation of the diet:phenotype connection. For the primary project, I initiated the growth of ten worm-pellets collected from each NGM agar and liquid culture dietary conditions, that result in differing phenotypic expression, and submitted samples to the University of Utah Metabolomics Core Facility. In the second project, I phenotyped four different species grown on high- or low-bacterial food conditions. Results thus far from the first experiment LC/GC- Mass Spectrometry metabolomics reveal that there are significant metabolite differences between conditions, specifically those related to the lipid and protein metabolic pathways. Results from the second experiment show that all four species exhibited significant differences in mouth form under dietary restrictive conditions. Collectively, these results suggest that the effect of diet on morph choice is a deeply-rooted phenomenon feasibly connected to lipid and protein catabolism. My current experimentation aims to use free fatty acid and amino acid assays on samples from the two conditions to deeper analyze differences in these pathways that could have significance in the mechanism behind chromatin modifications.
Molecular Dynamics Analysis of FMS
Taylor Ottley, University of Utah
Faculty Mentor: Dmitry Bedrov, University of Utah
SESSION D (3:30-5:00PM)
POSTER D76
The solid-electrolyte interphase (SEI) is one of the most important components of a Li-ion battery. The SEI forms from the breakdown of the electrolyte and anode during early cycling and serves as a passivating layer, leading to a longer battery lifespan. While many different compounds can form on the SEI, selective electrolyte choice can be used to control their formation. The use of fluorinated solvents allows for the formation of LiF, which allows for fast ion transport and suppresses non-beneficial reactions. The Bedrov group has conducted research on a newly proposed fluorinated solvent, 3,3,3-trifluoropropylmethyldimethoxysilane (TFPMDS). This solvent was compared to an traditional electrolyte cosolvent system using ethylene carbonate (EC) and ethyl methyl carbonate (EMC). Both solvents were studied with LiFSI molarity varying between 1 and 3 M. Molecular dynamics simulations of the systems found differing lithium-ion transport mechanisms. In the EC-EMC systems solubility of the LiFSI salt was high, leading to Li+ ions to be move highly independent of the FSI- molecules; this behavior was consistent over all concentrations. The TFPMDS systems, on the other hand, underwent a structural change as the concentration increased. At 1 M the LiFSI salt clustered together, stifling Li+ transport. However, as the concentration increased to 3 M the FSI- molecules began to form percolating ‘bridges’, creating new pathways for Li+ transport. Due to this, the conductivity of the two electrolyte systems had opposing trends. While the EC-EMC systems decreased in conductivity, from 7.59 mS/cm at 1 M to 4.22 M at 3 M, the TFPMDS systems increased in conductivity, from 0.103 mS/cm at 1 M to 0.230 mS/ cm at 3 M. These results matched well with experimental data from collaborators at South China Normal University. The understanding gained from this study will allow for further design of new fluorinated solvents utilizing this new transport method.
Characterization of Escherichia coli CheA Linker Mutants and their Effects on Intracellular Signaling
Savannah Romney, University of Utah
Faculty Mentor: Sandy Parkinson, University of Utah
SESSION D (3:30-5:00PM)
POSTER D77
Every motile cell and organism is able to monitor and track its chemical environment, a behavior known as chemotaxis. The chemotaxis machinery of bacterial cells like Escherichia coli enables them to move toward beneficial chemicals (attractants) and away from harmful ones (repellents). The “central processing unit” of the E. coli chemotaxis machinery is the CheA signaling protein. In my project, I created mutant CheA proteins in a 6-residue domain linker that is important for CheA signaling activity. I assessed the CheA mutant chemotaxis phenotypes on soft agar plates. Some residues supported chemotaxis; others did not. I plan to evaluate the cellular amounts and stability of CheA protein in each mutant. Stable CheA proteins were tested for their ability to regulate intracellular signaling activity in response to chemical stimuli. Further characterization of the functional defects of the mutated CheA domain will enable me to test a working model of CheA signaling.
An Instrument (TEOM™) Validation Study Using Air Quality Data from a Wildfire Smoke Event
Nancy Sohlberg, University of Utah
Faculty Mentor: A. Gannet Hallar, University of Utah
SESSION D (3:30-5:00PM)
POSTER D79
This study uses air particulate mass concentration data taken during a 5-day smoke event (9/9/2022-9/14/2022) in Salt Lake City (SLC) to demonstrate the functionality of a re-engineered 1405-DF TEOM™ instrument. The TEOM is designed to be set-up outside with a PM10 inlet head that removes particles above 10 μm in diameter out of a sample air stream, from which PM2.5 is then subsampled. This allows the instrument to take continuous mass concentration measurements of PM2.5 (particles with a diameter of 2.5 μm or less) and PMCoarse (particles with a diameter of ~10 μm or less) in the ambient air. We have re-engineered our TEOM to allow for a larger range of measurements for coarse mode particles by using a different inlet head that has been shown to sample particles up to 13 μm in diameter (Petersen et al., 2019). This inlet is located on the roof of University of Utah’s William Browning Building (WBB) and is connected to the TEOM via a large pipe that comes down into our lab where the instrument is located. Hawthorne Elementary school, located about 3 miles south west of the University of Utah, contains a 1405 series TEOM that follows the set-up laid out in the instrument’s standard operating procedure (Ray et al., 2009). This instrument is maintained so that its data can be reported to the EPA, and its PM2.5 mass concentration data is made publicly available. A comparison was done between the PM2.5 mass concentration data from the WBB TEOM and the Hawthorne Elementary TEOM for the period of 9/9/2022-9/14/2022 (fig. 1), which was characterized by a significant presence of smoke in the Salt Lake Valley due to wildfires in the western US. This period was chosen because of its prominent impact on PM2.5 levels, which makes for a more obvious data comparison. Strong correlation was found between the two data sets, suggesting a high degree of performance for the WBB TEOM. This result allows for more confident use of the WBB TEOM’s data, and with the instrument’s site located up near the Salt Lake Foothills, this data can contribute towards prevalent questions surrounding elevation impact on air quality differences in SLC. This result also opens up opportunity for more TEOM instruments sampling outdoor air to use an indoor instrument location coupled with a broader particle size range inlet. This unique set-up has the potential to extend instrument lifetime, increase instrument accessibility, and enhance instrument ability to sample larger particles like dust (a prominent coarse mode particle with significant environmental impacts).
REFERENCES
Petersen, R. C., Hallar, A. G., McCubbin, I. B., Ogren, J. A., Andrews, E., Lowenthal, D., … & Novosselov, I. (2019). Numerical, wind-tunnel, and atmospheric evaluation of a turbulent ground-based inlet sampling system. Aerosol Science and Technology, 53(6), 712-727.
Ray, A. E., & Vaughn, D. L. (2009). Standard operating procedure for the continuous measurement of particulate matter. Thermo Scientific TEOM.
Avalanche Activity and Plant Biodiversity in the Wasatch Mountains, Utah
Macey Tilk, University of Utah
Faculty Mentor: Mitch Power, University of Utah
SESSION D (3:30-5:00PM)
POSTER D81
The Wasatch Mountains of Utah are widely known for their steep vertical relief and significant seasonal snowpack. These two factors create dangerous conditions during winter storms in which the probability of an avalanche occurring increases. Physical factors such as temperature, snowpack depth, amount of relief and slope orientation are important considerations for avalanche risk, however, what’s happening below the snow on the ground may be just as important. Limited research has been conducted on the impact to plant diversity and how seasonal avalanche cycles may influence biodiversity over space and time. This study explores several well-known avalanche chutes to see if avalanche frequency plays a role in biodiversity. To study this, vegetation communities were studied through line transects perpendicular to avalanche paths. Species inventories were collected along each transect and were categorized into six dominant vegetation types (herb, forb, grass, shrub, juvenile tree, adult tree) to provide an index of community diversity. Maps were then created to capture the frequency of avalanches in each research site. Surprisingly, data analysis of community plant diversity in three study sites suggest that the higher frequency avalanche chutes contain higher biodiversity while less active chutes had lower biodiversity.
Accumulated Damage and Recovery in Drought-Stressed P. tremuloides
Hailey Wells, University of Utah
Faculty Mentor: Willliam Anderegg, University of Utah
SESSION D (3:30-5:00PM)
POSTER D83
Past research has demonstrated that multiple droughts can lead to accumulated hydraulic damages within plants, which has been a major contributor to large-scale quaking aspen die-off events in recent decades (Anderegg et al. 2013). This research project aims to better understand these compounded hydraulic changes resulting from repeated droughts and whether aspen are more susceptible to other stressors, particularly pathogen invasion, during or after a drought season. Over a two year-period, aspen propagules were raised in an experimental garden under four different treatment conditions: true-drought, recovering, once-treated, and control. In 2022, we measured drought stress responses throughout the growing season and took mortality surveys at the end of the season. We will now be quantifying and characterizing leaf microbiomes in each of the plants in an attempt to identify recognizable pathogens. We will then be analyzing whether water stress is potentially linked to increased pathogen vulnerability. This research will begin to answer larger questions about how plants allocate their resources under stress, and how compounded stressors can affect overall forest health year to year.
Anderegg, W.R.L. et al. 2013. Drought’s legacy: multiyear hydraulic deterioration underlies widespread aspen forest die-off and portends increased future risk. Global Change Bio. 19:1188-1196.
Ethnobotany and Medicinal Chemistry Investigation Culturally Relevant Medicinal Plant Species in Southern Utah
Kaleigh Rasmussen, Southern Utah University
Maisey Peterson, Southern Utah University
Kennedi Childs, Southern Utah University
Brionna Taylor
Faculty Mentor: Guizella Roccbado, Southern Utah University
SESSION D (3:30-5:00PM)
POSTER D85
Southern Utah is a place of great geo- and biodiversity, ranging from ancient rock formations to the myriad of plant and animal species occupying the desert ecosystem. It is perhaps this biodiversity that has drawn the Paiute people to settle here since ~1100 A.D. and allowed them to live and thrive in this land. Along with the majestic mountains and arid plains, there are many species of beautiful and useful plants that have served as medicine and been used for other purposes for generations by the Paiute people in this area. Medicinal plants have been used for millennia in all areas of the world, and are a current inspiration for the creation of synthetic drugs. However, these plants have been unsustainably harvested for these purposes to the point of endangerment or extinction. In Southern Utah many of these plant species have been used medicinally by the Paiute people for centuries. However, when it comes to scientific literature, little exploration has been done on Utah medicinal plants in relation to their ethnobotanical uses. The goal of this project is to bridge the gap between the chemistry of native Utah Flora and their cultural medicinal uses by the Paiute people in an effort to conserve the species along with the rich history that accompanies them. Our group has engaged in compiling data available on the plant species in Southern Utah that are endangered and have cultural significance to the Paitute people. In addition, we are gathering information on historical medicinal uses of these plants. Put together, these data sources reveal significant gaps of knowledge about these plants, and also uncover a great need of preserving culturally meaningful species in a more holistic manner.
Seasonal changes in worker fat content of Formica obscuripes, the western thatch ant
Christian Furness, University of Utah
Faculty Mentor: John Longino, University of Utah
SESSION D (3:30-5:00PM)
POSTER D87
Formica obscuripes is a species of thatching ant that thrives in semi-arid regions of the Western United States. They create dome shaped mounds out of twigs and are common in the state of Utah. Overwintering nests of F. obscuripes contain adult workers only, with no brood, yet brood is present in the Spring before foraging commences. This suggests workers are storing fat, which they mobilize to make new workers in Spring. We measured fat storage throughout 2022’s growing season, predicting an immediate decline in worker fat shortly after snowmelt and an increase in fat through the summer. We sampled 10 ants from each of 20 nests weekly, measuring wet weight, dry weight, and “lean” weight following the extraction of fat in hexane. Fat content was measured as dry weight minus lean weight, and water content as wet weight minus dry weight. Sampling occurred from the last week of April to the last week of October. Temporal dynamics of worker fat and water content were examined, with worker size and nests as covariates.
Bulk vs Serial Sampling in δ13C, δ18O, and 87Sr/86Sr Isotopic Analysis of Fossil Herbivore Teeth
Katya Podkovyroff, University of Utah
Faculty Mentor: Kaedan O’Brien, University of Utah
SESSION D (3:30-5:00PM)
POSTER D89
Since the 1970s, the fields of archaeology and geochemistry have used stable isotope analysis for reconstructions of paleodiets and other prehistoric behaviors which have since been used as evidence for topics such as human evolution, migration research, transitions to agriculture, among other topics. Focusing on tooth enamel has allowed researchers to avoid any diagenetic alteration damage since the tissue has high resistance to such a process. However, due to cost and effort, the vast majority of studies analyzing these elements utilize cross-sectional (bulk) sampling, rather than incremental (serial) sampling. Previous studies have shown that there are systematic offsets in values between the two methods, and quantifying these differences across different taxa within an ecosystem adds valuable information for future stable isotope research. In this study, we determine the extent to which information is lost about an organism’s diet, water intake, and movement when bulk, rather than serially, sampling along the growth axis of mammalian molars. We do this through the evaluation of samples taken from bovid and equid fossils dating to the Late Pleistocene of southern and western Kenya as a part of a larger project tracking seasonality and migration in eastern Africa from 100-12 ka. Our results for carbon, oxygen, and strontium isotopic analyses indicate that caution is needed when evaluating bulk sampled isotopic samples, as the majority of information stored in each tooth either remains unsampled or is averaged into a single neutral value, erasing information about seasonality and intra-year movements. This has strong implications for both how new research should best be conducted and how paleoecologists should interpret previous studies utilizing bulk sampling.
Environmental factors needed for juvenile success
MacKenzie Woodrum, University of Utah
Faculty Mentor: Austin Green, University of Utah
SESSION D (3:30-5:00PM)
POSTER D94
Human Influence is becoming increasingly ubiquitous across most landscapes in North America, forcing wildlife to adapt to ever-changing situations in order to persist. In this light, it is critical that scientists understand how wildlife behavior and distribution is affected by human influence. Recent research suggests that wildlife adapt to human influence in different ways, largely based on evolutionary taxonomy and life history characteristics, highlighting how interspecific variation in human influence response leads to differences in wildlife community structure across a wild to urban gradient. However, there is little work done on how individual species’ responses to human influence vary across major life stages (e.g., when raising young vs. when dispersing to new environments). Therefore, in this study, we will investigate how species use their environment in different life stages. Specifically, we will elucidate what elements of the environment are utilized at different stages of life and whether or not species responses to human influence change as they raise young. We will do this by comparing the distribution and habitat preferences of lone-adult vs. young-raising individuals, discovering the difference between the environments. We hypothesize that species distributions and habitat preferences, including responses to human influence factors, will vary across life stages. We predict that the presence of juveniles will make species more likely to avoid areas of higher risk, like areas rich with human development and recreational activity. This research will highlight the importance of studying wildlife during different life stages, making it possible for wildlife managers to better understand what elements of an environment that are critical to juvenile development.