Gabrielle Denonno★, Kat Arrizon★, Lauren ChanDepartment of Biological Sciences, ★SpeakerThe Northern Red-legged Frog (Rana aurora) is an amphibian native to the Pacific Northwest and a surrogate species for other wetland-breeding amphibians in the area. Previous research has indicated that the species may be declining due to anthropogenic land-use changes that have destroyed and fragmented its habitat. Investigating the impacts of habitat fragmentation on the movement of individuals and the connectivity of populations across the landscape can aid conservation efforts. To examine how habitat fragmentation has affected the Northern Red-legged Frog, we evaluate genetic diversity and connectivity within and among populations in the Portland, Oregon metropolitan region. We filtered and analyzed genomic data of individuals from 29 populations. We present estimates of heterozygosity and effective population size reflecting genetic diversity within populations. We also present principle component analysis (PCA) of genomic data and estimates of pairwise differentiation to identify distinct populations and patterns of gene flow. Our next steps include combining these genomic data with geospatial data to identify which aspects of the Oregon landscape best explain genetic diversity within a site and genetic differentiation among populations. We hypothesize that populations in areas with more human interaction will have less genetic diversity and experience greater isolation. |
Sydney Gutierrez★, Daisy Wong★, Lauren ChanDepartment of Biological Sciences, ★SpeakerHuman activity has fragmented natural landscapes, disrupting population connectivity and movement. With continued anthropogenic change, it is increasingly important to understand how specific landscape changes impact populations. The Northern Red-legged Frog (Rana aurora), is an amphibian that occurs along the Pacific Northwest of North America. This species requires both terrestrial and aquatic habitats for individual growth and development. Thus, the landscape composition and habitat quality are likely important to the persistence and connectivity in this species. This study aims to investigate how particular landscape features influence genetic diversity and connectivity among Northern Red-legged Frog populations in the Portland Oregon Metropolitan Region. Using Geographic Information Systems, we are characterising the environmental conditions both within and among breeding sites and evaluating how landscape features correlate with genetic diversity metrics among Northern Red-legged Frog populations. We hypothesize that the presence of intact forests and wetlands will increase connectivity while the presence of roads, impervious surfaces, and invasive species will decrease connectivity. Our results will help us understand how human-impacted landscapes may affect Northern Red-legged Frog movement and will provide data important for the conservation of this, and other wetland and forest species. |
Katherine Rees†★, Skye Foucrier★, Ryan Sekhon★, Lauren Hinrichs★, Jason Blank†Department of Biological Sciences, †Frost Support, ★SpeakerFrogs serve as model organisms for studying physiology of nerve, skeletal muscle and the heart in undergraduate biology labs. Heretofore, induced hypothermia has been the preferred technique for pain and stress reduction prior to euthanasia by pithing. AVMA guidelines discourage hypothermia and advocate chemical anesthesia before pithing, but the primary anesthetic used in aquatic vertebrates, MS-222, blocks nerve and muscle function in leopard frogs and renders them useless for classroom experiments. Eugenol is a safe and affordable anesthetic that is effective in amphibians. We sought to test the hypothesis that eugenol anesthesia is compatible with classroom nerve and muscle experiments on frogs. Bullfrogs and leopard frogs were immersed in a eugenol bath and reflexes were periodically tested. Immediately upon loss of reflexes, or after an additional soak period, the frog was pithed and the gastrocnemius muscle prepared for force measurements. We then stimulated the sciatic nerve at regular intervals and measured the minimum threshold voltage and maximum force output of the gastrocnemius. Control frogs were immersed in ice water and pithed when reflexes were substantially weakened, and the same measurements were taken. Eugenol induces loss of reflexes in approximately 30 minutes. Eugenol increases the threshold voltage and lowers muscle force, but neuromuscular preparations still maintain the ability to respond to electrical stimulation, suggesting that it is a useful option for classroom preparations. |
Damon Lin1★, Cooper Koenig2★, Madeline Bittner2★, Sam Kaplan1★, Mayumi Paraiso2★, Nasreen Buhn2★, Emily Stokes3★, Iris Ho1, Theresa Migler1, Paul Anderson1★, Jean Davidson2†★1 Department of Computer Science and Software Engineering, 2 Department of Biological Sciences, 3 Department of Chemistry and Biochemistry, †Frost Support, ★SpeakerComputational approaches are critical when dealing with complicated biological datasets, with many variables, stages, and unforeseen but potentially useful connections. Link prediction and entity resolution play pivotal roles in uncovering hidden relationships within networks and ensuring data quality in the era of heterogeneous data integration. Our research explores the utilization of large language models to enhance link prediction, particularly through knowledge graphs derived from transdisciplinary literature. Investigating zero-shot entity resolution techniques, we examine the impact of ontology-based and large language model approaches on the stability of link prediction results. Through a case study focusing on chronic lower back pain research, we analyze workflow decisions and their influence on prediction outcomes. Chronic pain is a great topic for this study, due to the many variables associated with this condition, the lack of coordination between siloed fields, and the millions of people affected by this condition without many treatment options. Our research underscores the importance of robust methodologies in improving predictive accuracy and data integration across diverse domains. |
Morgan Boyd1★, Claire Nodine2★, Cassidy Andrasz1, Joe Simopoulos3, Liane Wong1, Paul Anderson3, Jean Davidson1, Elena Keeling11 Department of Biological Sciences, 2 Biomedical Engineering, 3 Computer Science, ★SpeakerBotrylloides violaceus is a marine invertebrate able to fully regenerate its entire body, supplied by stem cells circulating in the blood, in a process known as whole body regeneration (WBR). Gaining insight into the regulation and expression of B. violaceus gene families associated with regeneration is key to developing a comprehensive understanding of WBR mechanisms. Recently, a novel de novo hybrid (short-read Illumina and long-read Oxford Nanopore Technologies (ONT)) genome was assembled and annotated for this non-model organism. In this study, we seek to produce a complete transcriptome from direct RNA (dRNA) long-read sequences generated by ONT. RNA was isolated from dissected B. violaceus tissues collected from a local marine pier, and libraries were prepared for direct sequencing using the ONT MinION flow cell. We are developing a pipeline for basecalling and read quality control (using Guppy), and reference-free assembly (using RNA-Bloom2). Further analysis will include genome mapping, comparison to a reference-based assembly and transcript analysis with splice variants. |
Amanda Martin†★, Spencer Thurman†★, Taylor Johnson†, Jean Davidson, Christy StrandDepartment of Biological Sciences, †Frost Support, ★SpeakerPythons are useful model organisms to investigate links between physiological processes related to feeding, digestion, and growth because pythons can be fasted for long periods of time to completely isolate the post-prandial period. Thus, pythons can be used to investigate how transitions between metabolic states regulate growth and maintenance both peripherally and centrally. Some work has been done on investigating effects of feeding on gene expression and physiology of peripheral organs, but no one has looked at how feeding affects gene expression in the python brain. To investigate this, twenty-one juvenile ball pythons were fasted for four weeks. Snakes were divided into 3 groups (n=7 for each group): Fasted (control) snakes that were not fed before sacrifice (C); Fed snakes that were sacrificed 1 day after a meal (1D); Fed snakes that were sacrificed 6 days after a meal (6D). Tissue from different regions of the brain was collected and flash frozen. For all brain regions, RNA was isolated, cloned into cDNA, and long-read gene sequencing is in progress using Oxford/Nanopore MinION technology. Ongoing work in our lab has begun this process for samples acquired from the telencephalon and some stomach tissue. Future analysis will be performed on tissue collected from the liver, fat bodies, hypothalamus, and small intestine to create a more robust impression of the trends observed. Comparative differential gene expression analysis will help in determining important physiological pathways involved with regulation of cell proliferation and growth. We expect to see upregulation of genes related to satiety, growth, cell proliferation and metabolism in the fed groups compared to the fasted group. |
Mary Jane Hartman★, Olivia Ferreri★, Matthew Bobbitt★, Mallary Greenlee-WackerDepartment of Biological Sciences, ★SpeakerInflammation is the normal response to infection, but excessive inflammation can lead to tissue damage. Neutrophils are the first responders during infection, and they release products that may modulate inflammation. Our lab has shown that neutrophils release more extracellular vesicles (EVs) when exposed to bacteria, and these EVs may associate with granule proteins, such as neutrophil elastase. Elastase degrades the extracellular matrix to create a path for migrating neutrophils, but it is quickly inactivated to prevent damage. However, one study showed that when elastase was associated with the surface of EVs, it could not be inactivated and contributed to chronic inflammation in mice. To explore whether our EV subsets possess more active elastase, we isolated EVs by ultracentrifugation, and used immunoblotting to show that more elastase was present on the EVs isolated from neutrophils challenged with bacteria compared to spontaneously released EVs. A colorimetric assay was used to measure active elastase, and as a control we first tested its release from human neutrophils. Indeed, neutrophils released active elastase when stimulated with fMLF and dihydrocytochalasin B. Our next steps will be to quantify elastase activity of EV subsets, and these data will provide insights into the role of EVs during inflammation. |
Megan Seth★, Mallary Greenlee-WackerDepartment of Biological Sciences, ★SpeakerMycobacterial species cause different human diseases, including tuberculosis and leprosy, but the mycobacterial cell envelope makes it difficult to treat with antibiotics. Given natural and acquired drug resistance, a new therapeutic is urgently needed. Antibody recruiting small molecules (ARMs) may help augment the immune response against mycobacterial infections. Our collaborators engineered ARMs that contain trehalose, a mycobacteria-targeting motif, and DNP, an endogenous-antibody recruiting motif. Our group showed that ARMs and antibodies enhance phagocytosis of M. smegmatis, so next we will test the hypothesis that ARMs increase bacteria killing via phagosome-lysosome (P-L) fusion. Compared to unmodified mycobacteria, ARMs increased phagocytosis and killing of mycobacteria within 24 hours. To verify the suspected mechanism of killing, we are optimizing a P-L fusion assay using LysoTracker to fluorescently stain acidic lysosomes. For these experiments, we will be using the J774.1 cell line, a model for mouse macrophages, and we have performed growth curves on these cells as part of their characterization. For P-L fusion assays, GFP-labeled Staphylococcus aureus will be added to cells and colocalization of LysoTracker will be monitored. If successful, we plan to apply this staining technique to unmodified and ARM-modified M. smegmatis to determine P-L fusion rates. |
Ben Schiff1★, Justin Grapentine2†★, Mallary Greenlee-Wacker21 Nutrition, 2 Department of Biological Sciences, †Frost Support, ★SpeakerSepsis is a dysregulated immune response to an infection and is one of the leading causes of mortality and hospitalization globally. One of the molecular hallmarks of sepsis is increased intravascular coagulation. We showed that extracellular vesicles (EVs) from neutrophils challenged with bacteria activate the coagulation cascade. We investigated the mechanism of EV biogenesis since inhibiting their production may decrease coagulation in sepsis. As a model for human neutrophils, we challenged differentiated HL-60 cells with S. aureus and isolated EVs by ultracentrifugation. We hypothesized that EV production was dependent on nSmase, an enzyme that produces membrane curvature. To test this, we inhibited nSmase with GW4869 and assessed EV production by flow cytometry, immunoblotting, and nanoparticle tracking analysis (NTA). Compared to EVs from untreated cells, there was less of the EV markers, flotillin-1 and CD81, when EVs were recovered from cells treated with GW4869. Despite this finding, NTA showed no decrease in EVs from GW4869-treated cells. Therefore, nSmase may play a role in cargo-loading, but not in EV biogenesis. Next, we will investigate whether calpain, a cytoskeleton-remodeling protease, plays a role in this process. Overall, determining the mechanism of EV biogenesis will provide insights into the role of EVs in disease. |
Eda McColl★, Dena GrossenbacherDepartment of Biological Sciences, ★SpeakerLupine flowers such as Lupinus succulentus have been observed with the banner petals of their flowers changing colors in response to pollination, which is believed to be a means of incentivising pollinators to visit flowers that have yet to be pollinated (Gori, 1989). The nature of this color change following pollination is not thoroughly researched and it is unclear as to how dependent the color change is on the type of pollinator or how effective the color change is in informing the choice of which flowers the pollinators visit. In this project, we are conducting an observational study on a group of 100 Lupinus succulentus inflorescences, both white bannered flowers and purple bannered flowers, and separating them into 7 observation groups. These groups will stand at a distance to avoid disturbing the pollinators, and keep tally of the visitation of the pollinators to the inflorescences, making note of the banner color visited, and the pollinator type present, those being Apis melifera (honey bees), members of the Bombus genus (bumble bees), members of the Megachilidae family (solitary bees such as leafcutter and orchard bees), and members of the Vespidae family (wasps). These results will then illustrate if there is a present preference between pollinators and the state of the inflorescences they visit. |
Molly Waddington1★, Rebekah Shane1, Kathleen Kay2, Dena Grossenbacher11 Department of Biological Sciences, 2 Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, ★SpeakerIn the family Polemoniaceae more than a third of species in western North America are polymorphic for flower color, often having both pigmented and unpigmented morphs. While the anthocyanin biosynthetic pathway responsible for most floral pigments is well known to impact pollinator attraction, it is also associated with tolerance to abiotic stressors such as drought. Here we use a comparative approach to test whether climatic water deficit (an index of plant drought stress) predicts flower color across 30 polymorphic Leptosiphon, Linanthus, and Phlox species using 1000s of iNaturalist observations. We predict that pigmented morphs (pink, purple or blue petaled) will be associated with sites with higher climatic water deficit relative to unpigmented morphs (white petaled). Support for this prediction would suggest that spatial variation in drought and the pleiotropic effects of flower color on drought tolerance contribute to the clade-wide maintenance of variation, potentially over deep evolutionary scales. |
Maya Netto†★, Dena GrossenbacherDepartment of Biological Sciences, †Frost Support, ★SpeakerWhen lupines are pollinated, their flowers change from white to purple, signifying to bees and other pollinators that these flowers no longer need to be pollinated. When studying wild lupines (Lupinus perrenis), the USDA states that although the flowers can self-pollinate, most breeding occurs through cross-pollination, as it yields more fruit and seeds and has fewer aborted seeds than self-pollinated flowers (Meyers, 2006). We use data collected from lupines in Miossi Open Space, which involves bagging inflorescences and applying three treatments to newly virgin flowers in each bag: self, outcross, no pollen. Bags are left on until the flowers senesce (banner color change recorded), and then the bags are removed. Fruit set will be further tracked in the treated flowers. Because lupines prefer cross-pollination, cross-pollinated Lupinus succulentus flowers likely exhibit a faster rate of color change than those self-pollinated. This suggest an influence of pollination preference on color change for Lupinus succulentus. |
Megan Koffinke★, Payton Southwick★, Ed HimelblauDepartment of Biological Sciences, ★SpeakerPreviously, six yellow-flowered mutant lines of Brassica oleracea were identified (the wild type color is white). Four of the six lines were found to have a mutation in the gene, CAROTENOID CLEAVAGE DEOXYGENASE 4b (CCD4b), including two nonsense mutations. CCD4b is expressed in developing flowers and has been shown to catalyze the breakdown of yellow carotenoid pigments to colorless products. Taken together, these observations make CCD4b a good candidate to have a role in determining flower color in Brassica oleracea. Our goal is to sequence the 5' unsptream, coding, and downstream 3' region of CCD4b from the two remaining yellow-flowered mutant lines to determine if they too carry lesions in CCD4b. |
Odberg Evan†★, Moniz Haley†Department of Biological Sciences, †Frost Support, ★SpeakerCalifornia is home to the Pacific newt (Taricha), which migrates annually to inhabit breeding pools after utilizing terrestrial habitats during the non-breeding season. This biphasic life cycle requires that newts adapt to the needs of two environments with significantly different hydric characteristics. Many newt species adapt by changing anatomically, such as the rugosity of their skin, which is likely accompanied by physiological changes that reduce their susceptibility to desiccation in terrestrial form or make it easier to absorb oxygen through their skin when in aquatic form in breeding pools. These adjustments may also impact the organs that control internal hydration and stabilize osmotic concentrations, which is crucial for maintaining homeostasis. Physiological changes associated with adopting an aquatic form may make breeding newts particularly sensitive to current and future drought conditions if aquatic habitats dry more rapidly than newts can return to a desiccation-tolerant terrestrial form. This study investigated changes in water loss across the skin surface in different life history phases of Taricha torosa. We measured cutaneous evaporative water loss (CEWL) and the internal hydration (e.g.through dissolved solutes in the blood) in terrestrial newts, aquatic newts, and first-year post-larval newts undergoing their first aquatic-to-terrestrial transition. Preliminary CEWL findings indicate that newts in their aquatic life stage exhibit the highest CEWL levels. Recently metamorphosed newts showed intermediate CEWL levels, while those in the terrestrial adult stage exhibited the lowest CEWL levels. The results suggest that anatomical changes associated with this unique life history transition impact water loss across the skin, making aquatic and recently metamorphosed newts more susceptible to desiccation. This can help estimate crucial hydric constraints imposed by anticipated climate change. |
Luke Hansen1★, Kellie Hintzoglou1★, Michael Jones21 Department of Kinesiology and Public Health, 2 Department of Biological Sciences, ★SpeakerThe posterior cervical and retropharyngeal regions are often overlooked and understudied in undergraduate human Anatomy and Physiology courses. The aim of this experiential Senior Project was to gain a deeper understanding of the gross anatomy in these regions through the processes of (a) human cadaver dissection and (b) review of primary literature on pathologies related to these regions. The dissection was performed on a male cadaver in the prone position, by progressively reflecting all posterior muscle layers of the cervical and posterior thorax regions. Major neurovascular structures were also identified, and all structures recorded in photography. The literature review provided clinical context for the importance of select structures that were revealed by this dissection. The deep posterior neck layer revealed the posterior suboccipital triangle including the rectus capitis posterior minor, a common source of cervicogenic tension headaches. Revealing this triangle ultimately allowed for removal of the head from the axial skeleton for posterior entry into the internal pharynx and larynx. As part of this advanced dissection, key spinal ligaments were revealed including the posterior longitudinal ligament which can become ossified, reducing cervical stability and increasing injury susceptibility. Performing advanced human cadaver dissection in conjunction with review of clinical literature provides pre-health students with unique and authentic opportunities to develop a deep understanding of human form in the context of dysfunction. |
Chloe D. Mickelsen1★, Jasmine C. Wong1★, Michael W. Jones DPT MS21 Department of Kinesiology and Public Health, 2 Department of Biological Sciences, ★SpeakerThe hidden nature of human pelvic anatomy has extended past its literal location and structure, and figuratively into societal stigmas. As a result of historical cultural norms and biases there has been a lack of public discourse, and a multitude of barriers to access and progress in pelvic health medicine. The aim of this Senior Project was to reveal male and female pelvic structures in a clinical context, for educational purposes. Pelvic health is equally important for both biologic sexes, so male and female specimens were included in this study. For investigation of female reproductive anatomy as related to aging and pelvic floor dysfunction, a hysterectomy was performed. The extracted organs and tissues were labeled and mounted for educational display. A male hemipelvis provided a unique opportunity for a deep pelvic floor dissection. Skillful display of the delicate male pelvic floor required removal of pre-existing internal organs and extensive comparative study using virtual atlas software, anatomical models, and primary resources. Clinically relevant findings from this study included evident muscular atrophy in the male, notably the puborectalis, and deterioration of reproductive organs in the female. These findings have clinical implications as pelvic atrophy can cause sexual and urinary dysfunctions, prolapse, pain, and negatively affect quality of life. This investigation of pelvic anatomy highlighted the importance of destigmatizing the human pelvis, directing efforts towards education, and removing the systemic barriers preventing access to pelvic health resources. Social stigmas surrounding pelvic health combined with a lack of comprehensive public education have contributed to keeping these structures hidden, both literally and figuratively. |
Ryan Anderson1★, Peter Felt2★, Michael Jones11 Department of Biological Sciences, 2 Department of Kinesiology and Public Health, ★SpeakerDeep within the back, hidden within an intricate framework of muscles and bones, is the spinal cord. This elaborate collection of cells (gray matter) and axonal tracts (white matter) works in conjunction with the brain to transmit impulses to and from the peripheral nervous system as an "information superhighway". This project's purpose was to perform a laminectomy procedure for the study of spinal and nervous system anatomy. The dissection involved various techniques, beginning with the reflection of the three layers of back muscles. Subsequently, a series of precise cuts were performed to remove the vertebral column and access the spinal cord. This approach provided detailed insight into the layered nature of the region and demonstrated the collaborative relationship of the nervous and musculoskeletal systems. A primary literature review of related pathologies was also conducted, providing clinical context for the anatomical structures revealed. Further exploration of the region defined the vital roles the back and spine play in posture and transmission of sensory and motor impulses. This hands-on experience provided an opportunity for an authentic interaction with the anatomical structures of a generous-willed body donation. |
Nell Shorin1★, Olivia Ortiz2★, Michael Jones21 Department of Kinesiology and Public Health, 2 Department of Biological Sciences, ★SpeakerThe purpose of this project was to perform a regional study of the intrinsic plantar foot, and to review current literature on related clinical conditions affecting this anatomical region. Performing a layered dissection of plantar foot structures allowed for a deep understanding of structures involved in foot biomechanics. It also provided a unique opportunity to learn about the authentic plantar abnormalities that impacted the life experience of this individual donor. Dissection of the four plantar foot muscle layers was conducted over five weeks in the Winter 2023 quarter at Cal Poly - SLO. The first intrinsic muscle layer contains larger prime movers of the toes, important for producing acceleration of the body during movement. The second layer transmits plantar neurovascular bundles to the many foot structures and musculotendinous structures responsible for metatarsophalangeal (lumbrical) flexion. The deepest two layers contain deeper neurovascular bundles and musculotendinous structures which collectively are involved in ground reaction force transfer and unilateral stance balance. The authors ultimately marveled at the astounding relationship between the structures of an anatomical region and how the form of those kinetically linked structures confer the many important mechanical functions that human feet perform. |
Pejalyn Balanon★, Lauren Emigh★, Claire Nodine, Keona Fernandez, Rachel Koinigsberg, Elena Keeling, Zane Sieger★Department of Biological Sciences, ★SpeakerBotrylloides violaceus is a marine invertebrate with close evolutionary ties to vertebrates and whole-body regenerative capabilities. Previous students obtained a draft genome for B. violaceus; this allows us to investigate specific genes in the Wnt signaling pathway, known for its evolutionary conservation and pivotal role in cell communication during development and regeneration. Using the draft genome, we found sixteen Wnt genes encoding signaling proteins and five Fzd genes encoding their receptors. We designed primers for each and have optimized PCR conditions for all the Wnt primers and most Fzds. We also refined DNA and RNA extraction methods, and cDNA synthesis. Our current focus is on using these primers to quantify relative gene expression via quantitative PCR (qPCR) in tissue from adult colonies. In the future, we will also investigate relative expression during different stages of development. Overall, these gene expression patterns can provide insight into possible roles of different Wnts in the development, function, and regeneration of B. violaceus. |
Anoushka Samuel★, Carolina Altbaum★, Rebecca Weber★, Elena KeelingDepartment of Biological Sciences, ★SpeakerTelomeres are repetitive DNA sequences at the ends of chromosomes that serve as protection from degradation by ensuring the maintenance of proper length during cell division. Telomere size decreases with age which limits the number of cell divisions and increases the risk of degenerative diseases; in various animals, stress is also a cause of telomere shortening. Our study focuses on the possible effects of noise and light stress on telomeres in Western bluebird nestlings. DNA was extracted from bluebird blood samples and purified, and qPCR was used to determine relative telomere length. Additionally, PCR and gel electrophoresis procedures have been conducted to ensure primer viability. Data thus far has revealed no significant correlation between relative telomere length and stress. Analysis of further bluebird blood samples may reveal an association. |
Olivia Watt1★, Gabriella Richardson1†, Kathryn Hutchinson1, Hanna Jaynes1†, Benjamin Daniels1, Daniel Peterson2, Elena Keeling1, Jean Davidson1, Crow White11 Department of Biological Sciences, 2 Animal Science, †Frost Support, ★SpeakerKellet's whelk, Kelletia kelletii, a kelp forest gastropod, fisheries species, and historical non-model species, is increasingly becoming a subject of research for understanding its ecology and management. A method for determining Kelletia kelletii sex non-invasively (e.g., without dissection) is needed to support cross-mating experiments and other research on this species. Genomics and molecular biology techniques were used to sex Kelletia kelletii non-invasively using a small sample of foot tissue. Dissection of whelks yielded samples for RNA extractions as well as physiological sexing for validation. Putatively sex-determining genes SOX9, FOXL2, WNT4, SRY, and DMRT1 were found through analysis of a previously assembled transcriptome, then aligned with sequences from model species to design primers for use in RT-qPCR to test for quantitative differential gene expression between males and females. Results found SOX9, WNT4, and DMRT1 showed significant differences in expression between male and female foot tissue. However, expression levels in confirmatory sex organ (i.e. penis (M) or egg capsule gland (F)) tissues showed no relationship of significant gene expression between males and females. These results were not conclusive, as the genes selected may not be direct indicators of sex determination in the foot tissue of marine mollusks. Current directions of this project include replicating the procedure with an increased sample size of foot and gonad tissue to verify results, as well as designing primers for and performing RT-qPCR on genes involved in the whelk endocrine system (estrogen, androgen, and testosterone receptors), as these genes are more likely to be functioning as direct indicators of sex determination in whelk foot tissue. |
Breanne Evans1★, Marin Vargas2★, Maria Shea2★, Luc Chone3★, Elena Keeling21 Department of Physics, 2 Department of Biological Sciences, 3 electrical engineering, ★SpeakerWith growing interest in alternative fuels, the potential for algae cell cultures to be used as a biofuel source has become a focus for experimental research. This multidisciplinary research project focuses on strategies for using electric fields to lyse algae cells through collaboration between the Biological Sciences, Physics, and Electrical Engineering departments at California Polytechnic State University, San Luis Obispo. As the biology team, we are particularly interested in 2 species of algae, Dunaliella salina and Chlorella vulgaris (which are saltwater and freshwater respectively). These two species of algae have different shapes, which may affect the electrical parameters for proper lysis in a pulsed electric field (PEF). We are studying the growth patterns of these two algae species with the end goal of creating cultures with uniform shapes and sizes in order to use energy more efficiently to lyse and harvest lipids. To measure the growth, we use direct counting and spectroscopy. Fiji: ImageJ is used to quantify uniformity and shape measurements. Learning more about the algae species will allow us to more efficiently and effectively use algae as a biofuel source. One method to achieve efficient lysis of algae cells involves the use of microfluidics. By directing algae through electrodes within a microfluidic circuit and consistently pulsing it with high voltage, you can ensure consistent and reliable lysis of the algae. |
Andy Aldecoa★, Brooke Fujioka★, Sarah Lord★, Azul Weldon★, Gita R. KolluruDepartment of Biological Sciences, ★SpeakerThe recent implementation of policies restricting funds for diversity, equity, inclusion, and justice (DEIJ) initiatives on college campuses has put these programs at the forefront of public discourse. Although the purpose of DEIJ is to correct inequities, criticism from some legislators has called the effectiveness of DEIJ in higher education into question. Our team conducted a literature review that emphasized the importance of DEIJ programs in supporting marginalized populations in university campuses, and consequently, the dangers of limiting them. These articles highlight the significance of affording every student an inclusive, equitable environment to further their personal growth and education. The Cal Poly Biological Sciences DEIJ committee recognizes the disparity in the effect of these policy changes on students' outcomes as evidenced by this research, and continuously supports the implementation of DEIJ programs given their success in reducing bias and barriers on our campus. |
Madeleine S. Kwon1†★, Sophia H. Hosmer-Hughes2†★, Tiffany A. Kwan2†★, Lena Kimura1†★, Zoe K. Lucchesi1†★, Gita R. Kolluru1†★1 Department of Biological Sciences, 2 Animal Science, †Frost Support, ★SpeakerMany species use UV reflectance patterns in communication. Fish have been shown to use UV reflectance patterns to identify conspecifics, make mate choice decisions, and find shoals (groups of conspecifics). Shoaling benefits fish by protecting them from predators and dilutes the risk of mating harassment. Our lab addressed whether females use UV patterns to shoal in the live-bearing fish Girardinus metallicus. We demonstrated that this fish exhibits UV reflectance patches compounded with iridescent, vertical barring that can be seen by humans. This signal may serve as a private communication channel because it may be invisible to predators. We tested whether females choose shoals behind UV+ barriers more often than behind UV- barriers. |
Sophie Short1†★, Adelle Wilkin1†★, Isaiah Orlando1, Lucy Nosbisch1, Heather Liwanag1, Maddie Schroth-Glanz21 Department of Biological Sciences, 2 Department of Statistics, †Frost Support, ★SpeakerPassive acoustic monitoring (PAM) efforts are essential to marine mammal conservation. Bioacoustic techniques can be preferred as visual surveys are time intensive, costly, and limiting. California's coastline is a biodiversity hotspot and a known migration corridor of multiple cetacean species, including gray whales, according to stock assessments provided by NOAA. Certain studies have indicated that gray whales vocalize during migration which can help confirm cetacean presence throughout the year. Off the coast of San Luis Obispo, California in an area that overlaps with the gray whale's southern migration, our team detected an unidentified knocking noise. Although gray whale vocalizations can be difficult to confirm, we believe these knocks are produced by this transient species. In order to determine the source of these knocking sounds, the goals of this project are to (1) classify the repetitive noise as biotic or abiotic, (2) perform a comparative analysis of various species to narrow down possible biotic candidates, (3) utilize records from local whale watching companies for more accurate evidence of species presence at the time of our deployment, and (4) examine temporal variation in the occurrence of this knocking sound. Acoustic monitoring provides information about migration of gray whales necessary for conservation efforts. |
Kseniya Krayeva†★, Sean Lema†Department of Biological Sciences, †Frost Support, ★SpeakerWarmer temperatures from climate change threaten to impact fish reproduction. For female fishes, changes in HPG axis endocrine signaling under high temperatures often leads to inhibited oocyte development, ultimately resulting in lower ovary mass, fewer or smaller eggs, and decreased egg viability. Some of those oogenesis effects materialize from diminished liver synthesis of vitellogenin egg yolk and choriogenin egg envelope proteins. However, it is unclear if changes in vitellogenin and choriogenin production arise solely from lower blood 17$\beta$-estradiol (E2), or if the liver itself becomes less sensitive to E2 at elevated temperature. Here, adult female Amargosa pupfish (Cyprinodon nevadensis) maintained at 20 C, 28 C or 36 C for 14 d were either collected directly from their tanks (baseline control), administered a single intraperitoneal injection of E2 (5 $\mu$g/g body mass), or given vehicle solution only (injection control). Both ovarian mass and plasma E2 were lower in females at 36 C compared to those from lower temperatures. Plasma E2 concentrations increased in females given exogenous E2 at all temperatures. However, E2 only upregulated liver vitellogenin and choriogenin gene transcripts in females at 28 C and 36 C, and not in females at 20 C. Those findings provide evidence that insufficient E2 stimulation of liver egg yolk and envelope protein synthesis contributes to impaired reproduction at elevated temperatures, but that diminished liver sensitivity to E2 may limit reproductive performance at low temperatures. |
Zoe Bixby†★, Lena Kimura†★, Adam Marin★, Serena Jenson★, Libby Hodge★, Daniel Cianchetti†★, Pahul Dhoat†★, Sean Lema★, Alejandra Yep★, Gita Kolluru★Department of Biological Sciences, †Frost Support, ★SpeakerMycobacterium spp. cause a common but untreatable bacterial infection in fish that is often fatal. We used a Mycobacterium outbreak in our fish colony as an opportunity to study the effects of infection on the behavior, physiology, and morphology of Girardinus metallicus, a livebearing fish. Our interdisciplinary study yielded for our collaborative team of behavioral ecologists and microbiologists to examine the effects of infection on the integrated phenotype. We compared the boldness, activity, and metabolic rate of infected and uninfected G. metallicus, prior to dissecting and staining their spleens to determine infection status. We hypothesized that a bacterial infection would alter phenotypic traits because infected fish must devote energy to fighting the infection. Interestingly, infected fish did not exhibit reduced body condition, suggesting that infection status cannot be accurately assessed using body condition. Furthermore, although infected fish tended to emerge from shelter faster, suggesting they are bolder, they took longer to recover from freezing when presented with a simulated predator, suggesting they are less bold. Our findings suggest that emergence tests may measure general activity rather than boldness, and that Mycobacterium may reduce fitness. These results may benefit fish labs and aquarium facilities. |
Lily Yenovkian, Heather LiwanagDepartment of Biological SciencesCalifornia has been experiencing record-breaking storms along its coasts in recent years, associated with both El Nino events and global climate change. The current literature for pinniped populations suggests that coastal storms like these are a leading cause of mother-pup separation. Indeed, there have been multiple accounts of northern elephant seal (Mirounga angustirostris, NES) pups becoming separated from their mothers during intense wave action periods, and this separation is often lethal for the pups. To evaluate how these recent storms have impacted our local NES population in San Simeon, California, I will analyze a seven-year database including climatic factors (wind, tidal levels, and precipitation) in relation to NES distribution and population size at the Piedras Blancas NES breeding site. I will model how the abundance of each age class differs among beaches throughout the breeding season, both before and after the storm events. Furthermore, I will assess the influence of climatic changes on pup mortality by comparing abundance of NES pups and weanlings in years prior to and during more extreme weather conditions. Pup mortality has also been correlated to beach population density in other studies. To verify if this same relationship is true at our breeding site, I will conduct a regression analysis between population density and the abundance of pups that successfully survive to weaning across beaches at our site. By identifying how large-scale climatic events are impacting our local NES population, we can inform management decisions for the continued conservation of this ecologically important marine predator. |
Claire Savage†★, Heather LiwanagDepartment of Biological Sciences, †Frost Support, ★SpeakerHarbor seals (Phoca vitulina) are coastal marine mammals that haul out close to areas of human activity, but they are notoriously reactive to human disturbance. Because their overall population is doing well, there is currently no monitoring program documenting the occurrence of harbor seals along the central coast of California. Plans for a windfarm offshore of Morro Bay are likely to increase ship traffic and other human activity in the Morro Bay area. The goal of this project is to document the location and timing of harbor seal haulout behavior in Morro Bay and surrounding areas. To do this, we will use binoculars and a spotting scope to conduct frequent ground surveys of harbor seals in Los Osos, Estero Bay, and Estero Bluffs. We will relate harbor seal haulout behavior to abiotic factors, including tide level, air temperature, and wind, and we will also note harbor seal reaction to human presence, when applicable. This information will generate baseline data regarding harbor seal presence on our local shores, and will investigate what factors most influence harbor seal haulout behavior in our area. In the future, these data will be used to understand the impacts of the increased activity associated with the offshore windfarm on our local harbor seals. |
Enrique Lecha★, Liv Springer, Heather LiwanagDepartment of Biological Sciences, ★SpeakerPiedras Blancas in San Simeon, CA is home to the largest mainland breeding colony of northern elephant seals (Mirounga angustirostris), estimated at over 25,000 seals. The Vertebrate Integrative Physiology (VIP) lab at Cal Poly conducts regular surveys of the seals, to estimate the population and track trends throughout the year. Accurately estimating population numbers using ground surveys is a challenge. The natural camouflage with the environment allows for seals to hide from view when a researcher may be counting from a peripheral or level perspective. The use of an unmanned aerial vehicle (UAV) can improve the accuracy and efficiency of our population census for the Piedras Blancas colony. When deployed, the UAV follows a pre-programmed flight pattern to take overlapping aerial photos of the entire beach. Once these photos are collected, they need to be stitched together to create a single image per beach before they can be analyzed to generate seal counts. Since 2021, the VIP lab has collected hundreds of aerial photos, and our team has gone through a stitching and tagging process to create an overall census of the Piedras Blancas northern elephant seal colony. We are analyzing the images for comparison to our concurrent ground surveys, to determine whether the use of a UAV is in fact increasing the accuracy of our seal counts. We are generating data for the development of recognition software that will use artificial intelligence (AI) to enable automated surveys of these tagged drone images. |
Emily Prince★, Serena Jenson★, Adam Marin★, Chris Athens, Alejandra YepDepartment of Biological Sciences, ★SpeakerUrinary tract infections (UTIs) are the second most common bacterial infection, primarily affecting women. As increases in antibiotic resistance complicate therapy, our research aims to discover a novel approach targeting the high-affinity iron acquisition systems of uropathogenic Escherichia coli (UPEC). Iron acquisition is an attractive target as iron is essential for bacterial growth and is limited in the urinary tract. We assessed a library of 12 compounds synthesized by Dr. Eagon's lab, including a previously studied parent compound, for their efficacy at inhibiting UPEC growth. We generated growth curves of UPEC CFT073 with and without 3$\mu$M iron to ensure that iron was both an essential and limiting nutrient for bacterial growth. Subsequently, each compound was assessed via dose-response curves against UPEC strain CFT073 WT and $\Delta$tolC mutant to reveal their relative inhibitory abilities. Five compounds inhibited growth under iron-limiting conditions, two of which revealed improved IC50 values (1.93 $\pm$ 0.05 and 1.7 $\pm$ 0.1 $\mu$M) compared to the parent compound (8 $\pm$ 2 $\mu$M). We will continue this lead optimization approach and explore a second library of compounds. This research validates iron acquisition as a viable target for antibacterial strategies against UTIs. |
Serena Jenson1★, Sienna Stromberg2★, Jackson Baldis2★, Alejandra Yep11 Department of Biological Sciences, 2 Department of Chemistry and Biochemistry, ★SpeakerOur project studies growth inhibition of uropathogenic Escherichia coli (UPEC), the main cause of urinary tract infections, to explore novel treatments. Specifically, we target the TonB system, responsible for powering multiple outer membrane receptors in UPEC that bind required nutrients, such as cobalamin and iron. Currently, we are adapting and improving activity assays for characterizing TonB inhibitors. The first assay will require making a mutant UPEC strain with a deletion in the metE gene, which encodes a cobalamin-independent methionine synthase, forcing the strain to become cobalamin-dependent for growth. Therefore, we can directly correlate growth to TonB activity and measure it under variable concentrations of cobalamin, to compare with similar conditions when a TonB inhibitor is added. Another assay measures iron uptake by fluorescently labeling FepAS271C, a TonB-dependent receptor which transports ferric enterobactin (FeEnt) into E. coli. Fluorescence is quenched when FeEnt binds to FepAS271C, but rebounds as FeEnt enters the cell. Fluorescence is expected to decline with TonB inhibition because FeEnt will stay bound to FepAS271C rather than entering the cell. We describe the process of generating the mutant strains and other reagents required for these assays. The assays will be instrumental for discovery and development of novel inhibitors of the TonB system that can inhibit growth of UPEC. |
Ana Banuelos1†★, April Valdez-Garcia1†★, Natali Ceja2†★, Alexis Espinoza3†★, Alexi Ringler4★, Bianca Cruz1★, Xavier Aguilar1★, Ariela Rugendorf5, Dayanara Ramirez1†, Alejandra Yep6†, Jasmine Nation1†1 Department of Liberal Studies, 2 Biomedical engineering, 3 Industrial Technology & Packaging, 4 Computer Science, 5 Nutrition, 6 Department of Biological Sciences, †Frost Support, ★SpeakerWe describe the university-school partnership Nuestra Ciencia, which tackles two parallel sets of challenges: 1) recruitment and retention of Latinx people into STEM professions, and 2) microbiology misconceptions, such as how vaccines work and preventing food contamination. Nuestra Ciencia addresses both, as we develop engaging experiments for elementary school students that illustrate microbiology concepts by visiting bilingual classrooms and hosting field trips to lead experiments in Spanish. We also provide bilingual instructional materials to take home and pre-activity questionnaires that involve families in science discussions. In this poster, we outline the program's background, goals and components, activities developed, potential impact, and lessons learned. Our research questions include what are elementary students' microbiology preconceptions, their relevant ideas from everyday life, what are elementary and undergraduate students' attitudes towards science and scientists, as well as whether participation in Nuestra Ciencia impacts those preconceptions and attitudes. Our ongoing work focuses on developing and piloting a set of activities related to food safety for grades 4-6. In this lesson we focus on the four steps to avoid food contamination: chill, separate, cook, and clean through interactive, hands-on activities. This lesson has two parts, one where students rotate through four stations, each focusing on a different step, and another where students learn how food can become contaminated by unclean hands. We have developed and piloted these lessons for over one-hundred bilingual 4th and 6th grade students in the Learn by Doing Lab. |
Sophia Brooks1†★, Kelsey Cliburn1†★, Kassandra Gonzales1†★, Brooke Imamoto1†★, Marissa Young2†★, Alejandra Yep1†1 Department of Biological Sciences, 2 Department of Animal Sciences, †Frost Support, ★SpeakerThe bacterial movements swimming and swarming are powered by proton-motive force and flagella. Swimming is individual bacterial movement through semi-solid media while swarming is coordinated movement on solid media. Various uropathogenic microbes are capable of swarming, a virulence factor in catheter-associated urinary tract infections. The uropathogenic strain Escherichia coli CFT073 is capable of both swimming and swarming. The CFT073 $\Delta$tolC mutant can swim, but loses swarming capability. TolC is an efflux pump in the outer membrane of bacterial cells. We hypothesize that TolC is required to secrete a substance that helps in swarming such as a surfactant or quorum sensing molecule. Swapping supernatants of the $\Delta$tolC and WT strains grown in liquid has no significant results, however when swapping the supernatant of the WT strain grown on solid media, swarming of $\Delta$tolC is induced. We are currently experimenting with adding external surfactants (Triton-X100, SDS, bile salts) to test whether they rescue the non-swarming phenotype of the $\Delta$tolC mutant. Future areas of experimental exploration include metabolomic analysis of supernatants to compare the composition of WT and $\Delta$tolC grown in swarming agar and a study of whether secretion of a molecule(s) required for swarming motility is lost in the $\Delta$tolC mutant. Our research contributes to the understanding of regulation of swarming motility in uropathogenic E. coli. |
Lucia Mendoza†★, Jin Ko†★, Jean Sharmaine Paclibare†★, Alejandra Yep†Department of Biological Sciences, †Frost Support, ★SpeakerUropaghotenic Escherichia coli (UPEC) is the most common cause of urinary tract infections (UTIs). Motility is a major virulence factor of UPEC, in particular flagella-powered movement in liquid (swimming) or solid (swarming) media. Working with UPEC strain CFT073, we have identified an efflux mutant, tolC, which loses the ability to swarm while retaining the ability to swim. TolC is the main efflux pump of Gram-negative bacteria, and its link with swarming is not understood. Ongoing results from our lab suggest that a molecule(s) secreted when UPEC CFT073 grows in swarming agar may be able to rescue the $\Delta$tolC phenotype. We hypothesize that this molecule(s) functions either as a surfactant or as a signaling factor. In an effort to understand this phenotype, we looked at other gene deletions that result in the same phenotype. A systematic single-gene deletion study on a commensal strain of E. coli (Inoue et al., 2007, J. Bacteriol. 189:950-7) uncovered 216 such genes. We focused on a subset of 68 genes with unknown functions at the time of publication and used NCBI databases to look for their function. Based on this information, we propose potential linkages between $\Delta$tolC phenotype and these other non-essential E. coli genes, specifically, tonB, macA, yfgL, mdtH, fadK, nlpl, and LPS genes. The genes mentioned function in iron acquisition, efflux, cell division, and LPS. Furthermore, we outline future plans to determine these relationships experimentally. |
Sophia Brooks1†★, Kelsey Cliburn1†★, Kassandra Gonzalez1†★, Brooke Imamoto1†★, Marissa Young2†★, Alejandra Yep1†1 Department of Biological Sciences, 2 Department of Animal Sciences, †Frost Support, ★SpeakerUrinary tract infections are common bacterial infections primarily affecting women. Swimming, the ability of bacteria to move in liquid, and swarming, a collective movement on solid surfaces, are two flagella-driven types of motility that contribute to virulence of uropathogenic Escherichia coli. In the model uropathogenic strain CFT073, the $\Delta$tolC mutant lacks the main outer membrane efflux pump. CFT073 $\Delta$tolC loses the ability to swarm, but retains the ability to swim in semisolid media. TonB is part of the transmembrane complex TonB-ExbBD, which transduces energy generated by the proton-motive force across the cell membrane to activate outer membrane receptors, most notably, iron acquisition receptors. Interestingly, the double mutant CFT073 $\Delta$tonB/$\Delta$tolC can both swim and swarm, similar to the WT strain. Because iron deprivation is known to increase motility, and a $\Delta$tonB mutant lacks the ability to import most iron sources, we hypothesize that iron limitation rescues the non-swarming phenotype of the $\Delta$tolC mutant. We are currently testing a variety of iron conditions including iron supplementation to the media and iron deprivation by addition of the fungal siderophore deferoxamine mesylate. Our results will contribute to the understanding of swarming motility regulation in uropathogenic E. coli, particularly under iron deprivation conditions that mimic the urinary tract environment. |
Jacqueline Pickel★, Kamille Peralta★, Julia Johnson†★, Alejandra YepDepartment of Biological Sciences, †Frost Support, ★SpeakerAntimicrobial resistance (AMR) is one of the most pressing modern public health threats. The World Health Organization estimates AMR contributed to 4.95 million deaths in 2019 and the World Bank estimates $1trillion additional healthcare costs due to AMR by 2050. Emergence of AMR as a result of misuse and overuse of antibiotics is well studied, yet the contribution of biocide exposure via cross-resistance mechanisms remains understudied. We adapted commensal and uropathogenic strains of Escherichia coli to three widely used food preservatives on solid and liquid media. We confirmed stability of adaptation and quantified susceptibility to the food preservative in an adapted MIC assay. From this series of adaptations, we identified five isolates with sustained resistance to their subsequent biocide. Adapted isolates were then tested in MICs against an antibiotic panel, from which two isolates showed increased resistance to multiple antibiotics.These isolates exhibiting cross-resistance to antibiotics have been sent out for genome sequencing to identify mutations, and we are currently in the process of finding Single Nucleotide Polymorphisms (SNPs) through variant calling analysis. This work will identify pathways of resistance to commonly used biocides that contribute to antibiotic cross-resistance. |
Kamille Peralta1★, Jackie Pickel2★, Julia Johnson3★, Juli Bishop1★, Angelina Peralta3★, Yesenia Ceja3★, Kathryn Hutchinson3★, Suzanne Phelan1, Alejandra Yep31 Department of Kinesiology and Public Health, 2 Nutrition , 3 Department of Biological Sciences, ★SpeakerUncomplicated urinary tract infections (UTIs) are the second most common microbial infection, affecting up to 60% of women. There is very limited research on occupational risk hazards for UTIs, but long shifts, poor access to toilets, low water intake, and extended time in crouched positions have been proposed to increase UTI risk. Although multiple reports link farm working to an increased risk for UTIs, there has been no study specifically focused on this risk in farm working populations. Cal Poly's Mobile Health Unit (MHU) provides free non-emergent medical and preventive health services to uninsured women in Santa Maria and Guadalupe, CA. We propose to develop a multilingual survey to investigate whether specific farm working conditions increase the likelihood of UTIs. Additionally, pesticide exposure is another common hazard of farmwork and 53% of MHU patients report prevalent exposure. We propose to investigate whether adaptation to commonly used pesticides in Santa Barbara county can lead to antibiotic resistance in uropathogenic strains. Our research will contribute to the limited knowledge we have regarding the adverse health effects that farmwork, including pesticide exposure, can have on underrepresented community members. |
Abbi Bennitt†★§, Ashley Adams, Nikki AdamsDepartment of Biological Sciences, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerPlastic pollution and its effects on marine organisms has been documented since the mid-1900s. Microplastics, fragments or fibers of plastic smaller than 5mm, are pervasive throughout marine ecosystems and have been found in the guts of the smallest marine organisms causing deleterious effects. Suspension feeders, like Pacific Oyster, Crassostrea gigas, that accumulate these microplastics on and in their gills and guts, may be at the highest risk of physiological distress. C. gigas is an ecologically and economically important aquaculture species and a part of a multibillion dollar per year fishing industry. Oysters are susceptible to anthropogenic pollutants, like microplastics, which may alter their immune function. To test the effects of microplastics on the C. gigas immune system, I exposed oysters to variable concentrations of microplastic spheres (mps) (0 mps/L, 1*10$^4$ mps/L, 1*10$^5$ mps/L, 1*10$^6$ mps/L) for one week. After exposure, I extracted, preserved, and counted hemocytes from the oysters to quantify their immune response. The average number of hemocytes in oysters exposed to the highest concentration of microplastic spheres was significantly higher than the average number of hemocytes in the control oysters (p<0.05). There were no significant differences in the concentration of hemocytes among the lower microplastic and high or control exposures. Our results reveal a positive trend of increasing concentration of microplastic spheres and the average number of hemocytes in C. gigas, indicating oysters may become more immunocompromised when there is a higher concentration of microplastics in the environment. |
Charles Barthauer1★, Grace LeGassick2, Maya Lavorando2, Lois Petty2, Candace Winstead1★1 Department of Biological Sciences, 2 SLO Bangers, ★SpeakerPeople using intravenous drugs are at high risk for acquiring Hepatitis C Virus (HCV) making syringe services programs ideal locations for screening and linkage to care. We will describe our incentivized program along with several years of program data demonstrating the many barriers faced by our participants who test positive for HCV in accessing treatment. These data include field notes and forms collected during test counseling conversations as we help HCV positive participants navigate the healthcare system. This research will forward our goal to streamline our linkage process, advocate for creative solutions to reduce barriers and provide treatment and a cure for all. |
Ella Leback★§, Zoey Wall★§, Leah Hawkins★§, Danielle DeBrine, Nikki Adams§Department of Biological Sciences, §Santa Rosa Creek Foundation Support, ★SpeakerMicroplastics (plastic fragments or fibers smaller than 5mm) are pervasive throughout global ecosystems, having been detected in water, sediments and both aquatic and terrestrial organisms. For the past two years, the Adams lab has been monitoring microplastics in the sediments and oysters of the Morro Bay Estuary. Our results indicate that oysters contain microplastics in their gills and digestive tracts, that microfibers are the most abundant type of microplastic, and that the abundance of microplastics in the sediments may be impacted by seasonality and water flow. Therefore, it is important for us to quantify microplastics in the water column. We are supplementing our ongoing microplastic monitoring efforts by examining the concentrations and types of microplastics in seawater every two weeks at six well-established field sites within the Morro Bay Estuary watershed (including an upstream freshwater stream, Chorro Creek). We are currently processing samples using KOH digestion of organic material, filtration, staining and identifying plastics using fluorescence microscopy. We will analyze our results using R to compare microplastics across parameters. We hypothesize that microplastics will vary among sites and be highest in the back bay where microplastics may originate from terrestrial and agricultural sources and linger for longer periods in the slower-moving water. This project will establish a long-term monitoring effort that will help us understand the sources and movements of microplastics we have identified in the Morro Bay Estuary. We hope to inform stakeholders about sources of microplastics and ways to avoid further contamination in the future. |
Stella Raymond1†★, Dana Twisk2, Allyson Taylor2†, Heather Liwanag11 Department of Biological Sciences, 2 Graduated Cal Poly, †Frost Support, ★SpeakerWeddell seals (Leptonychotes weddellii) are the southernmost breeding mammal on Earth and therefore face extremely cold and windy conditions from birth. Like other phocid (true seal) pups, Weddell seals are born with lanugo (neonatal fur) and no substantial blubber layer. Unlike many phocid pups, however, Weddell seals begin swimming in polar waters at around two weeks of age, often before they have fully molted their lanugo. Due to the high thermal conductivity of seawater relative to air, this is thermally challenging for young pups; indeed, Weddell seal pups with lanugo exhibit higher metabolic rates in water than in air. We hypothesized that the lanugo of Weddell seals would be morphologically distinct from adult pelage, and that these differences would make lanugo pelts superior insulators in air and in water, compared to adult pelts. To test this, we compared morphological characteristics (hair length, circularity, and density) of Weddell seal lanugo (n=6) and adult pelts (n=5), and we measured the thermal function (thermal resistance) of both pelt types in air and water. We found that lanugo hairs were longer and more circular compared to adult hairs, and lanugo pelts had a higher fur density compared to adult pelts. As expected, both pelt types had reduced thermal resistance in water compared to air. Additionally, neonate pelts had higher thermal resistance than adult pelts in both conditions. These results demonstrate the importance of the lanugo coat for thermoregulation in Weddell seal pups, while they develop their blubber layer. This has implications for how climatic changes that accelerate melting of the fast ice, where Weddell seals breed, could impact pup energetics and survival. |
Emma Garrison★§, Schuyler Gooley★§, Emma Buckley§, Travis Mallory§, Clinton Francis§Department of Biological Sciences, §Santa Rosa Creek Foundation Support, ★SpeakerThe Black Oystercatcher, Haematopus bachmani, is an intertidal obligate bird species found along the West Coast of North America. Listed by the U.S. Fish and Wildlife Service as a "focal species for conservation", there is concern that the species is at risk for endangerment due to anthropogenically induced factors. Over the past decade, monitoring efforts by the Black Oystercatcher Monitoring Project across the Central Coast have found relatively low nest-success rates, averaging at around 22% per attempt, which raises concerns for population persistence. In 2023, we monitored nests along the coast of San Luis Obispo to determine nest fate, overall productivity, and sources of failure. We monitored 25 breeding pairs across 32 nesting attempts. Fifty-seven eggs were laid, 14 of which were successfully hatched, and ten chicks successfully fledged across seven nests. Additionally, we compiled photographs of Black Oystercatcher eyes from individuals within their breeding territories because female eye-fleck patterns appear to be individually identifiable. This means that eye-fleck patterns may be a novel tool for resighting and identifying the same individual over time. Our database of eye-fleck photos associated with territorial breeding pairs may serve as a valuable and non-invasive way to monitor the longevity, success, and movement of Black Oystercatchers. |
Elizabeth Norris★, Clara Mcmahon★, Dr. Larisa VredevoeDepartment of Biological Sciences, ★SpeakerThe microflora of insects and other arthropods may provide a novel source of antibiotic-producing bacteria. Ticks and other blood-feeding arthropods harbor a unique array of symbiotic bacteria in their gut, including their core microbiome and microbes acquired while feeding on hosts, which may colonize these arthropods for a period of time. Tick-borne pathogens circumvent such responses to replicate and subsequently be transmitted to humans and other animals. Other potential colonizers derived from the host may be thwarted by the core tick microbiome via competition and production of antimicrobial compounds. Such antimicrobial compounds produced by tick native microflora may be of interest to combat medically-important pathogens. In this project, we investigated local tick species as a source of antibiotic-producing bacteria. Several species of adult ticks were collected from Poly Canyon at Cal Poly. Ticks were surface sterilized and homogenized to cultivate endosymbiotic bacteria on culture media using standard microbiological procedures. Antibiotic sensitivity assays were run to identify isolates capable of inhibiting a range of human-associated bacterial species, suggesting production of antimicrobial compounds. Assays revealed four isolates that demonstrated antibiotic-producing potential. Future steps for the project include characterization and testing of these isolates against fungi to detect potential anti-fungal compounds and focused isolations of tick-derived actinomycetes because of their reputation for producing antibiotics. |
Treasure Joyce†★§, Ashley Adams§, Nikki AdamsDepartment of Biological Sciences, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerMicroplastics are defined as particles less than 5 mm in length and range in shape (fibers, spheres, particles) and chemical composition (polyethylene, polystyrene, nylon, etc.). Polyethylene is found in some of the most common plastic products including plastic bags and disposable water bottles. In studies, including those performed in Morro Bay, microfibers are found in higher concentrations than other types of microplastics. The California purple sea urchin (Strongylocentrotus purpuratus) is a model and ecological indicator organism in California ecosystems that has planktonic embryonic and larvae life stages that are sensitive to pollutants. The objective of this study was to identify whether microfibers cause abnormal and delayed development of sea urchin embryos. S. purpuratus embryos were exposed to 60 $\mu$m microfibers in a control (0 mg/L), low (0.5 mg/L) and high (1.7 mg/L) treatments. We compared timing of the first cleavage stage and whether later development was on time and normal or abnormal every 24 hours for four days after fertilization. Exposure of embryos to microfibers did not significantly affect early cleavage rates (p>0.05). Nevertheless, exposure to microfibers decreased normal development and embryos incurred increasing abnormalities over time of exposure. For example, high concentrations of microfibers caused significant abnormalities in development at 24 and 96 hours (p<0.05). Low (more environmentally relevant) microfiber concentrations caused significant abnormalities in development at 96 hours (p<0.05). Therefore, embryos exposed to microfibers experience negative consequences to development. |
Annika Sorensen†★, Amanda Martin†, Taylor Johnson†, Christi Strand†Department of Biological Sciences, †Frost Support, ★SpeakerSnakes exhibit phenotypic flexibility in their gastrointestinal organs based on different feeding patterns. The adaptation of reducing organ mass during fasting and rapid upregulation during feeding is energetically favorable and allows for minimal tissue maintenance during prolonged periods of fasting. After feeding, the luminal presence of nutrients causes enterocytes to expand along the gastrointestinal tract, while the liver mass also increases in some snake species. In this experiment, ball pythons were sacrificed at 1D and 6D post-feeding with a fasted control group. Samples from the stomach, small intestine, and liver were collected and embedded in paraffin, passed through H&E staining, and will be examined by light microscopy to quantify hypertrophy and hyperplasia for each group. The goal of this study is to confirm the pattern of phenotypic plasticity in the GI tract in response to feeding that other snakes tend to follow. |
Regan Holub★§, John Bychok★§, Carver Rodman★§, Kristin Hardy§Department of Biological Sciences, §Santa Rosa Creek Foundation Support, ★SpeakerThe Pacific Oyster (Crassostrea gigas) is the primary oyster species cultivated in aquaculture on the US West Coast. Oyster farms today experience high mortality rates - often associated with heat stress and hypoxia - with sterile triploid oysters dying in greater numbers than diploid oysters (often up to ~50% stock loss). Despite their increased rate of mortality, farmers still prefer to grow triploids as they grow faster and lack gonads, which collectively increases their commercial value. As an economically important bivalve species, it warrants understanding the physiological processes that influence oyster resiliency during environmental stress. The purpose of this research is to evaluate if sublethal stress-conditioning of juvenile C. gigas can increase their survival when they experience environmental stress during the subsequent grow-out period on commercial farms. To this end, we pre-treated juvenile oysters (<40 mm) for 5d to one of the following conditions: control (15C, 8mgO2/L, 31ppt), hypoxia (15C, 2mgO2/L, 31ppt), or heat stress (21C, 8mgO2/L, 31ppt). Pretreatments were followed by 3wks of recovery in a flow-through raw-seawater system at the Cal Poly pier. Following recovery, half of the oysters were outplanted on a commercial shellfish farm in Morro Bay, and the remaining oysters were used in lab-based stress physiology challenges. We exposed these oysters to: anoxia (15C, 0mgO2/L, 31ppt), heat-shock (35C, 8mgO2/L, 31ppt), or control (15C, 8mgO2/L, 31ppt) conditions and monitored mortality rates over time. Additionally, six individuals per replicate treatment were subsampled following 48h of exposure for comparative measurements of 1) total antioxidant capacity, 2) glycogen, and 3) microalgal feeding rates. The data from this project will provide valuable information on potential procedural options for increasing survival and stress resiliency in farmed triploid Pacific oysters. |
Libby Hodge★, Haley Russell, Jennifer VanderKelenDepartment of Biological Sciences, ★SpeakerRepeated or consistent exposure of bacteria to biocides can select for individual resistant cells giving rise to a population of biocide-adapted bacteria. We are investigating whether the adaptation of Pseudomonas fluorescens and Escherichia coli to a food preservative, diacetyl, is correlated with increased resistance to antibiotics, a phenomenon called cross-resistance. Bacteria were adapted to diacetyl by sequential exposure to the biocide using a disk diffusion method. The resulting diacetyl-adapted strains from both species were analyzed using minimal inhibitory concentration (MIC) assays for cross-resistance to various antibiotics. Cells were exposed to different concentrations of antibiotics to determine the lowest concentration (MIC) that inhibits cell growth. Resistant cells can grow in higher concentrations of antibiotics. Three of the P. fluorescens diacetyl-adapted strains consistently showed cross-resistance to both chloramphenicol and ciprofloxacin antibiotics. Compared to the wild-type response to antibiotics, 5 of the E. coli diacetyl-adapted strains showed a slight decrease in sensitivity to gentamicin. Both results indicate that adaptation to diacetyl provides a competitive advantage when exposed to antibiotics. The development of antibiotic resistance poses a huge challenge to modern healthcare so it is vital we understand all mechanisms under which it can develop. Our ongoing work includes sequencing the cross-resistant strains to determine the mechanism of cross-resistance. |
Ashley Adams1★§, Abbi Bennitt1§, Dorothy Horn2, Kristin Hardy1, Nikki Adams11 Department of Biological Sciences, 2 California State University Channel Islands, §Santa Rosa Creek Foundation Support, ★SpeakerOysters are important ecosystem engineers. They create habitat for other estuarine organisms and are capable of filtering large volumes of water, which improves bay and estuarine water quality. The Pacific Oyster, Crassostrea gigas, is a cosmopolitan and important species that may be susceptible to anthropogenic pollutants such as microplastics. Microplastics (mps, pieces of plastic smaller than 5mm) come in many shapes (fibers, angular pieces, etc.) and chemical compositions and are widely bioavailable in the marine environment. Microplastics are known to induce changes in inflammatory response and energy metabolism and reduce lysosome membrane stability in C. gigas, among other physiological responses. We investigated whether exposure to environmentally relevant concentrations (0, 10, 20, 40 mps/oyster) of low-density polyethylene microplastic fibers for two weeks would cause differences in the concentration of hemocytes. Following exposure, we collected gill and digestive gland tissue to measure microplastic consumption by treatment group over time and we preserved hemolymph and performed total hemocyte counts (THC). Oysters exposed to microfibers consumed microplastics. Exposure to microfibers caused a significant dose-dependent increase in the production of hemocytes (P<0.01). For example, exposure to 20mps/oyster and 40 mps/oyster caused a significant increase in THC compared to the controls and the 10mps/oyster (p<0.001). Exposure to 10mps/oyster did not cause a significant increase in THC compared to controls (p>0.05). To our knowledge, these data are the first to demonstrate that microfibers induce an immune response in C. gigas. |
Samantha Valentine1†★, Caroline Mackenzie2†, Tim Bean21 Animal Science, 2 Department of Biological Sciences, †Frost Support, ★SpeakerThe state and federally endangered giant kangaroo rat (Dipodomys ingens) endemic to the San Joaquin Valley of California serve as a keystone species and ecosystem engineer. Burrowing behavior and granivorous diet characteristic to the giant kangaroo rat shape the ecosystem by providing shelter for other sensitive species in the ecosystem and dispersing seeds across the landscape. However, the giant kangaroo rat is listed both federally and in California as endangered due to habitat degradation, agricultural activity, and rodenticide usage. A continued decline in population may call for ex situ conservation efforts, where understanding the quality of feed presented to the animals will become important. Additionally, investigating nutritional composition between native and invasive seeds may explain preference for native seeds observed in the literature and highlight the importance of preserving native vegetation. Kangaroo rats select for seeds high in carbohydrates as their body is adapted to their dry habitat by generating water through metabolic activity. Carbohydrates can include various components such as liganin, starch, neutral detergent fiber, and acid detergent fiber. This research will explore seed carbohydrate composition of seeds of native plants Lepidium nitidum and Lasthenia californica and invasive plants Bromus madritensis spp. Rubens and Erodium cicutarium, to determine whether the giant kangaroo rats are selecting seeds for a specific carbohydrate to generate a greater amount of metabolic water. |
Laney Hall★§, Isaac Qi-Yue Ng★§, John Paneno§, Dr. Kevin Johnson§Department of Biological Sciences, §Santa Rosa Creek Foundation Support, ★SpeakerAs climate change progresses, the increasing amount of CO2 is driving ocean acidification which has been shown to negatively impact shell and skeletal development of invertebrates, such as oysters and coccolithophores. These vital species are the foundation of food webs. Without them, coastal ecosystems will deteriorate. But macroalgae can help prevent this outcome; it increases the pH through uptake of CO2 and excess nutrients. This project focuses on designing macroalgae tumble tanks, specifically targeting growth optimization at the Cal Poly Pier. The goal of this study is to examine how different marine algae species impact seawater acidity. Determining which species has the fastest growth rates and impacts on seawater chemistry can be helpful in identifying species for culturing with integrated multi-trophic aquaculture systems (IMTA). Seaweeds integrated into IMTA systems can provide benefits to seawater pH if grown upstream of shellfish, thereby facilitating increased growth. Seaweeds can also provide benefits to seawater nutrient loads if grown downstream of organisms through the uptake of excess nitrogen. This project to date has evaluated two species and 3 tank designs and found significant changes in seawater chemistry with each seaweed species cultured. |
Sarah Lord†★, Zane Warsen, Evan Odberg, Brandon Kong, Haley Moniz, Emily TaylorDepartment of Biological Sciences, †Frost Support, ★SpeakerCalifornia newts (Taricha torosa) are a species of salamander endemic to California and are currently threatened due to factors such as habitat loss and extended duration of drought. Although they are terrestrial for a good portion of the year, these newts become aquatic when breeding. Thus, newt populations often reside near freshwater habitats such as ponds and streams and typically return to the same sites annually. Their breeding season spans from 6-12 weeks in mid- to late winter, and females lay gelatinous egg masses on submerged objects such as vegetation or rocks. The choice of oviposition site by the female is key to her reproductive success, yet very little research has highlighted the microhabitat preferences of California newts, and there are no published descriptions of site choice for T. torosa. To examine microhabitat selection of egg mass deposition, we conducted field surveys observing egg deposition sites across several ponds, measuring variables including relative temperature, dissolved oxygen, depth in water column, distance from pond edge, height from pond bottom, substrate type, and substrate width. Additionally, we conducted surveys on newt breeding behaviors to gauge relative activity across the ponds. Results of this work will help identify important freshwater habitat features to preserve for the future of this species. |
Tatum Schneider1★§, Kevin Johnson1§, Greg Schwartz2§1 Department of Biological Sciences, 2 Bioresources Agricultural Engineering, §Santa Rosa Creek Foundation Support, ★SpeakerCultivation of seaweed in recirculating aquaculture systems provides many benefits when co-cultured in multi-trophic systems. One species that is currently gaining commercial interest for co-culture in such systems is seaweed with a herbivore (e,g purple sea urchins or abalone). Cultivation of urchins and abalone can successfully be done with artificial seawater; however, there is limited data on the viability of these artificial salts for the cultivation of marine seaweeds. To address this gap, I have developed a mobile recirculating aquaculture system (MRAS). In the development of the MRAS, I have tested the potential to cultivate Ulva sp., and Gracilaria sp. using artificial seawater. To date, our trials have revealed growth rates ranging from a 30% to 90% increase in biomass over 3-day intervals, with fluctuations linked to nutrient concentrations and the health of the seaweed. Through testing different species, I determined the optimal stocking density to be 1 gram per liter, with nitrate concentration ranging from 40 to 20 ppm. Here I will present the system design and share data from 6 trials conducted to date, made possible by the generous support of the Santa Rosa Creek Foundation. A future phase of this system will include the addition of sea urchins or abalone to the MRAS tanks to evaluate gonad production in a mobile system when fed each species. |
Lily Nielsen★, Tyler Cannon★, Hannah Peter★, Michael Black PhDDepartment of Biological Sciences, ★SpeakerSaccharomyces cerevisiae is a cost-effective model to study HIV assembly. Expression of HIV Gag in S. cerevisiae results in virus-like particle (VLP) formation; VLPs can be isolated via ultracentrifugation and analyzed for HIV gRNA content via RT-PCR. Previous experiments in this lab have indicated successful VLP isolation and gRNA recovery. However, following a recent retransformation of yeast strains, the same VLP recovery has not been observed. This project seeks to investigate which altered variable(s) could be resulting in poor VLP/gRNA yield. The spheroplasting enzyme, the media used for yeast propagation, and the selectable marker (changed from ClonNAT to TRP1 upon retransformation) are three variables of interest. To test the spheroplasting enzyme, a VLP formation/gRNA isolation procedure was completed with the enzyme previously used, and the enzyme used following retransformation of experimental strains; western blot results indicated slightly increased VLP recovery with the original enzyme, yet no gRNA was isolated. To test the media and selectable markers, new media will be prepared and yeast will be transformed with the ClonNAT plasmid. A VLP isolation in both current (low yield) and previous conditions will be performed for both variables. VLP and gRNA recovery levels will be compared via western blot and RT-PCR. |
Zoey Dale†★§, Janae Shew, Henry Marden, Hayley Mapes, Sean Lema§Department of Biological Sciences, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerPhysiological responses to stressors commonly include elevations in glucocorticoid hormones. Those increased glucocorticoids alter energy allocation and utilization through effects on glycolysis and gluconeogenesis. As part of that change, energy is typically shifted away from somatic growth. However, the specific mechanisms whereby elevations in glucocorticoids affect growth are not fully understood. Here, we examined effects of handling stress on glycemic status and endocrine growth pathways in juvenile olive rockfish (Sebastes serranoides). Olive rockfish were netted to create an acute 'handling stressor', and a blood sample was rapidly taken for a 'baseline' (0 hour) time sample. Handled fish were then returned to their holding tanks for 2 hours, after which time fish were recaptured and liver tissue and blood collected. Fish exposed to the 'handling stressor' showed increases in plasma cortisol and glucose from the 0 hour baseline to the 2 hour 'post-stressor' sampling period. Accompanying those changes, liver mRNAs for insulin-like growth factor binding proteins (Igfbp)-1a and -1b were elevated at the 2 hour sampling time in handled fish. In fishes, type 1 Igfbps inhibit Igf1 action, and the up regulation of liver igfbp1a and igfbp1b gene expression suggests that increased type 1 Igfbp levels may act to inhibit growth following handling stress. These findings suggest some of the effects of glucocorticoids on growth may occur via Igfbp1 modulation of Igf1 availability. |
Jasmine Wu†★, Marie YeungDepartment of Biological Sciences, †Frost Support, ★SpeakerCitrus fruits are enjoyed worldwide due to their delicious flavor, beneficial nutritional compounds and antioxidant properties. However, they are susceptible to mold contamination during postharvest stages, which leads to huge economic losses in the agricultural industry. Synthetic fungicides, such as tebuconazole and strobilurin are commonly used to combat this. However, consumer concerns regarding potential health risks and environmental impacts, such as reported human liver toxicity and water system contamination, have sparked interest in natural preservatives. This study assesses essential oils (EO) and chitosan's effectiveness against molds, particularly Geotrichum spp. and Penicillium spp, affecting postharvest citrus fruits. Spores were harvested and purified after 5 days of incubation on PDA or SAB agar at 25 degrees Celsius. Initial spore counts were determined using TEMPO with the most-probable-number based method . We isolated 1.8 x 10$^8$ MPN/g and 3.0 x 10$^7$ MPN/g of spores from Penicillium and Geotrichum, respectively. These initial spore counts are needed for evaluating fungicide efficacy. Clove bud EO, oregano EO, and 1% chitosan were chosen as alternative fungicidal agents as previous literature suggests they may act on fungal cell walls and membranes. Well established in vitro methods, such as the agar well diffusion assay and minimum inhibitory concentration (MIC), will be used to study their efficacy on inhibiting Penicillium and Geotrichum. To assess real-world applications of natural fungicide and possible interactions with produce, Citrus tangerina will be treated with at least 10$^7$ MPN/g spore inoculum, followed by EOs and/or chitosan. After incubation, mold growth will be quantified in homogenized Citrus tangerina. The initial and final spore count will be compared. Our findings will contribute to the development of safer fungicide alternatives for the agricultural industry, promoting both food safety and human safety. |
Halley Carson†★§, Heather Liwanag†§Department of Biological Sciences, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerUnlike most mammals, northern elephant seals (Mirounga angustirostris) exhibit an unusual physiological phenomenon known as a catastrophic molt, which involves the shedding of patches of skin and fur in the process of replacing their pelage annually. Remarkably, they undergo this energetically costly process while fasting. Although several studies have examined the timing and environmental influences on the molt in southern elephant seals, this process remains understudied for northern elephant seals. This project will document the timing of the molt in different age classes of northern elephant seals and will provide novel information regarding how the catastrophic molt affects thermoregulation in these large marine endotherms. To do this, we will conduct ground surveys during the annual molt, noting the number of seals by age class at the beaches of the Piedras Blancas elephant seal colony. Because adult females and juveniles haul out for their molt at a different time than the adult males, these surveys will document the phenology of the molt according to age class. To investigate how the molt affects thermoregulation, we will take infrared thermal images of the animals at different stages of the molt. These images will quantify the surface temperature of the animals across the body, before, during, and after the catastrophic molt. In addition, we will document abiotic weather factors, including air temperature, wind, and sunlight levels, to provide context for these thermal measurements. This will be the first study to document the timing and thermal consequences of the catastrophic molt in northern elephant seals. |
Hayden Dillon1†★§, Jake Roth2†, Katie Saenger2§, Heather Liwanag2§1 Animal Sciences, 2 Department of Biological Sciences, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerThe northern elephant seal (Mirounga angustirostris, NES) is a well-known polygynous breeding species, with males defending harems including as many as 100 females. Male-male competition during the breeding season is well documented in NES, but there very little information about this behavior at the Piedras Blancas rookery, the largest NES mainland breeding colony. This study aimed to better understand the dominance relationships among male NES at the Piedras Blancas rookery and how these relationships affect mating and aggression behavior. The goals of this study were to (1) establish dominance rankings for focal NES males based on their displacement interactions and (2) correlate aggressive behaviors and copulations with those different dominance rankings. To do this, we tracked individual males (n=114) throughout the breeding season, identified by a unique hair dye mark on their side, and observed their behavioral interactions via visual surveys twice per week during the 2021-2023 breeding seasons. For each observation, we recorded the specific dominance behaviors (e.g., vocalization, rearing up, chasing) of each focal seal, as well as factors such as the age class of the seal, mating attempts, and mating success. At the end of each season, we assigned a dominance ranking to each focal seal based on the number of males he displaced, and we assigned a submissiveness ranking to each focal seal based on the number of times he was displaced by another male. We found that aggressive behaviors and copulations were positively correlated with dominance ranking (P<0.001), but dominance ranking did not correlate significantly with age class (P=0.1706) . Interestingly, dominance rank and submission rank were not inversely correlated, indicating that the dominance hierarchy is complex. Characterizing behavioral dynamics during the breeding season will provide insight into this complexity and help us understand what makes individual male NES successful in this polygynous breeding system. |
Zoe Chevalier1★§, Maria Lopez Neri2★§, Sage Mayer1★§, Reena Nagra3★§, Andrea Diaz2★§, Ethan Landry2§, Leslie Aguilar2§, Avery Schurhoff3§, Ella Schoenwetter1§, Natalie Almeria2§, Abbey Huff2§, Zoe Bixby2§, Gena Bentall4, Lisa Needles2§1 Natural Resources, 2 Department of Biological Sciences, 3 Animal Sciences, 4 Sea Otter Savvy, §Santa Rosa Creek Foundation Support, ★SpeakerLong-term ecological monitoring can help inform potential factors influencing recovery of at-risk species. The southern sea otter (Enhydra lutris nereis) remains at risk despite intensive management efforts. Re-establishment of sea otters into historically occupied habitats is of primary interest to managing agencies and understanding changes in otter prey composition can provide information about the diet, health and carrying capacity of otter populations. While there is substantial data on sea otter foraging in coastal habitats, little is understood about characteristics of foraging during expansion into estuaries. In Morro Bay, CA, the otter population has increased in the last twenty years. However, until recently, otters primarily occupied the region towards the mouth of the bay and were infrequently observed in the back part of the bay. To understand spatial and temporal patterns in sea otter foraging, we conducted foraging observations of otters at different areas within Morro Bay. We found differences in prey composition between the mouth and back bay with crabs comprising a greater percentage of sea otter diet in the back bay. These findings are consistent with other studies in which otter diet shifts from primarily epifaunal invertebrates to more infaunal species as otter populations in an area increase. As otters expand into the salt marsh, we are also assessing their foraging behavior in this novel habitat. Our study can help inform managers by predicting sea otter foraging behavior during natural or facilitated range expansion into estuarine habitats. |
Nick Gammal†★§, Lucy Nelson★, Alexis PasulkaDepartment of Biological Sciences, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerEpifluorescence microscopy is an important tool for characterizing the abundance, size structure, and composition of marine plankton. It provides a means for quantitative measurements of size, shape, and trophic mode. By linking phytoplankton data with measurements of environmental parameters, we can gain a better understanding of how plankton communities vary in respsonse to environmental change. We used epifluorescence data from a time series collected at the Cal Poly Pier to design and construct a robust pipeline for sample collection, microscopy, image analysis, and data analysis/integration. This pipeline for analyzing plankton with epifluorescence was then used in a study focused on characterizing the spatial variability of phytoplankton within the Morro Bay Estuary. Samples were collected along transects within Morro Bay to link changes in plankton community with environmental gradients. We found that the environemental conditions within the bay were distinct between May and August. The differences reflected stratified conditions in May (reflecting more typical summer conditions) and a late Summer upwelling event in August. Community composition among plankton were also distinct between the two transects, with a greater plankton abundance in May driven by a cryptophyte bloom and a lower abundance in August with greater proportions of diatoms. Size spectra were correlated with silicate concentration and temperature, but not nitrate concentration. By continuing to integrate the plankton community structure with environmental parameters, we aim to better understand the factors influencing their distribution patterns within the estuarine ecosystem. |
Jaden Hansen★§, Alexis Pasulka§Department of Biological Sciences, §Santa Rosa Creek Foundation Support, ★SpeakerThe dinoflagellate species Akashiwo sanguinea is an increasingly recurrent harmful algal bloom former present in warming oceans globally. Under optimum environmental conditions, A. sanguinea blooms can have deleterious impacts on marine ecosystems and cause harm to organisms including shellfish, birds, fish, and zooplankton. To understand A. sanguinea bloom dynamics along the central coast of California, we isolated three strains from the Cal Poly Pier in San Luis Obispo Bay (CP1 and CP2) and the T-pier in Morro Bay Estuary (MB1). We characterized A. sanguineas growth dynamics at varying temperatures (14, 16, 18 degrees C) in vitro (e.g., growth rates and maximum densities). Further, we investigated the bacteria associated with A. sanguinea cultures at exponential growth and explored A. sanguineas allelopathic effects on a model green algal species, Dunaliella tertiolecta. Our results showed that the growth dynamics of A. sanguinea strains varied among selected temperatures. CP1 and CP2 exhibited higher exponential phase growth rates and reached higher cell concentrations than MB1 across all temperatures. Additionally, CP1 inhibited growth of D. tertiolecta at both 1:1 and 4:1 CP1 and D. tertiolecta ratios, respectively, with a higher inhibition rate at 4:1. A. sanguinea strains displayed distinct bacterial communities; CP1 and CP2 were dominated by the Rhodobacteraceae family, particularly Pseudophaeobacter and Ruegeria, respectively, while MB1s bacterial associates were more diverse and contained several genera from both the Rhodobacteraceae and Flavobacteriaceae families. |
Zach Hunter★, Marie YeungDepartment of Biological Sciences, ★SpeakerStandard plate count (SPC) is frequently used to quantify bacterial cells. While culturable cells presumably form the majority of viable cells in a sample, cultures in stationary phase contain many viable but non-culturable (VBNC) cells, which culture-dependent methods like SPC cannot detect. This study intends to optimize a workflow for quantification of Vibrio parahaemolyticus using quantitative polymerase chain reaction (qPCR) and DNA spectrophotometry. The speed and specificity of qPCR make it attractive for cell quantification, but this application requires a set of standards of known quantity from which to create a standard curve. In lieu of SPC for this step, we developed a culture-independent workaround suited to small operations with limited resources. After V. parahaemolyticus RIMD2210633 was grown to stationary phase, DNA was extracted with the Qiagen DNeasy PowerSoil Pro kit. Using the SpectraMax Plus spectrophotometer, $\mu$g/mL DNA was calculated from OD$_{260}$ readings, and our strains sequence data was used to convert $\mu$g/mL DNA to genome copy number. Serial dilutions of these DNA extracts were amplified by qPCR (Rotor-Gene Q by Qiagen) using a primer set targeting the thermolabile hemolysin gene characteristic of the species. We were thus able to correlate cell count with threshold cycle (Ct). 10, 100 and 1000-fold dilutions of whole-cell suspension (n=3) exhibited an average Ct of 10.1, 13.3, and 16.5 cycles, respectively. Using the OD$_{260}$-derived standard curve, the average density of V. parahaemolyticus in overnight culture was calculated as 9.16*10$^8$ cells/mL, which correlated well with SPC-based predictions. While preliminary results are promising, more testing is needed to substantiate the accuracy and precision of this procedure. Additionally, digital PCR and propidium monoazide are emerging culture-independent methods that we will be investigating to amend this workflow for greater reliability and reproducibility. |
Marissa Bills1†★§, Ryan Bloom1★, Carolyn Key1★, Isa Mattioli2★, Laney Hall1★, Gabe Anderson1★, Ethan Fernandez3★, Sage Mayer3★, Anna Foer3★, Megan Emi3★, Alexa Cango Ruiz3★, Sasha Evans1★, Jacob Hinshaw1★, Lucy Thackray1★, Madeleine Yang1★, Ben Ruttenberg11 Department of Biological Sciences, 2 Cal Poly Animal Science, 3 Cal Poly NRES, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerPismo clams (Tivela stultorum) are an iconic shellfish species particularly important to the California Central Coast. They can be found from Monterey Bay, CA to Baja California, MX but the epicenter of their population in California was Pismo Beach, or the "Clam Capital of the World". They supported a brief commercial fishery in the first half of the 1900s and then a robust recreational fishery up until the early 1980s when their populations declined to levels that functionally closed the recreational fishery. Populations on Pismo Beach remained low until clams began reappearing in 2015. This coincided with the Ruttenberg Lab's creation of the Pismo Clam Project; a collaborative project to monitor Pismo clam populations locally to increase our understanding of their current status, possible reasons for their decline and what management could help support their recovery. With a decade of data later, we've documented an incredible change in their population and contributed significantly to our understanding of this iconic intertidal clam. This poster highlights some of our findings from the past decade and the work being done in our lab currently. |
Amoreena Adams★, Isabella Simpson★, Marie YeungDepartment of Biological Sciences, ★SpeakerVibrio parahaemolyticus is a bacterium of public health concern due to its potential to cause foodborne illness. Warming ocean temperatures enable these mesophilic bacteria to thrive better in their native marine environment. In recent years, there has also been a rising concern in the level of microplastics in the environment. We hypothesized that microbes can colonize microplastics; and thus, the accumulation of microplastics by filter-feeders would further enhance the proliferation of V. parahaemolyticus in seafood, posing health hazards to consumers. The objective of this study was to investigate the impact of microplastics (polyethylene) on the growth of a cocktail of two V. parahaemolyticus strains in oysters (Crassostrea gigas). Oysters were purchased from Giovanni's fish market and maintained in a glass tank with artificial seawater circulating at 19-21C. High concentrations of V. parahaemolyticus (2.1 x 10$^9$ CFU) and two different amounts of polyethylene beads (200 or 800 mg/10 L) were added into the tank containing 15 oysters. Cell counts of V. parahaemolyticus in water and oyster tissues were determined over several days using a selective medium thiosulfate-citrate-bile salts-sucrose agar. Preliminary results showed that the number of V. parahaemolyticus increased over time. The homogenized oyster tissues contained about 5.0x10$^3$ to 7.6x10$^3$ CFU/g after 24 h. By 72 h, oysters exposed to lower and higher microplastic levels contained 1.6x10$^4$ and 1.5x10$^4$ CFU/g, respectively. The similar microbial load was also observed in water, which yielded 2.1x10$^3$ and 2.4x10$^3$ CFU/mL after 96 h between the two microplastic levels. Therefore, our current data suggest that the presence of up to 800 mg/10L polyethylene does not affect the growth of V. parahaemolyticus in oysters. More research will need to be done to test the effect of higher concentrations of microplastics for longer time period. |
Maya Netto1†★, Danika Cornejo1†§, Nikki Arm2, Crow White11 Department of Biological Sciences, 2 Mechanical Engineering, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerA Federally-designated Wind Energy Area (WEA) has been created off the coast of Morro Bay in anticipation of a deepwater offshore floating wind energy farm. Because this type of renewable energy system is new and has not been well-tested, questions remain about the potential environmental impacts of this technology. Under the advising of Dr. Crow White, we have worked to develop methods to conduct biological surveys in the WEA before and after the development of the wind energy farm. We specifically focused on Baited Remote Underwater Video (BRUV) surveys, conducted using a deep ocean lander, which is fitted with a camera and bait system to attract and record benthic marine life, such as sharks, flounder, fish, crab, and octopus. Throughout the summer of 2023, I worked alongside Danika Cornejo, a marine science undergraduate, developing a Before-After-Control-Impact (BACI) experimental statistical study; and Nikki Arm, a mechanical engineering graduate student, working to develop and fit a deep ocean lander for BRUV survey purposes. We developed the methods necessary to complete a BRUV survey in the WEA and optimize the results of the deep water benthic marine life surveys in coastal California. The lander underwent modifications and field testing involving altering light wavelength emission, video/image capturing, soak time, and bait systems. We were able to collaborate with NOAA to deploy the lander from the R/V Fulmar and Shearwater in August and November. Through these deployment attempts, further useful modifications were discovered in areas such as deployment/retrieval methods and upgraded GPS location systems. |
Jacob Landa†★, Erin Ituralde†★, Sonia Patil†★, Daniel Bercovici†Department of Chemistry and Biochemistry, †Frost Support, ★SpeakerYlidenenorbornadienes (YNDs) are bridged bicyclic molecules that can be created from [4 + 2] cycloaddition reactions between fulvene and acetylene derivatives. YNDs can undergo a Michael addition with a thiol nucleophile, yielding 4 diastereomers. Each diastereomer has been found to fragment at a different rate via a retro-[4 + 2] cycloaddition reaction when heated. Our goal is to study the kinetics of this retro-[4 + 2] cycloaddition fragmentation with diastereomers of YND-Propanethiol (YND-PT) that have been prepared with dimethyl fulvene and acetylene mono- and dicarboxylate esters, in order to better understand how differences in the stereoelectronics of YND-PTs with carboxylate ester substituents effect the rates of their decomposition. |
Angelo LaCommare-Soto1★§, Erik Smith2†★, Kel Mussetter1§, Brent Boone2†§, Daphne Moon2†§, Emily Bockmon2†§1 Department of Biological Sciences, 2 Department of Chemistry and Biochemistry, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerEstuaries are dynamic environments that exhibit large natural variability and often have complex carbonate chemistry due to their many biogeochemical and physical drivers. Starting in 2019 monthly discrete samples were collected in the Morro Bay estuary to monitor seawater chemistry conditions and later nutrient concentrations. Recently the estuary has experienced large fluctuations in its biogenically critical eelgrass population, which likely changes short-term seawater biogeochemical variability. Throughout the year, high alkalinity is observed in the back bay due to freshwater input and long flushing times, which buffers the estuary, maintaining less acidic seawater conditions. Freshwater also brings high concentrations of dissolved inorganic carbon into the back bay in the winter months, along with higher concentrations of nitrate and silicate, which are otherwise generally low in the front bay. Analysis of seawater alkalinity and pH, paired with salinity, temperature, nutrient, and tidal data, contributes to an understanding of the biological and physical drivers of the observed carbonate variability. This understanding may provide clues to the causes and effects of observed changes to the bay coinciding with seagrass habitat changes and a clearer understanding of how the estuarine environment will respond to future carbon dioxide emissions and resulting acidification. |
Patrick Harmon★, Jennifer CarrollDepartment of Chemistry and Biochemistry, ★SpeakerSynthesis of 1,1-diphenylpropan-1-ol via a solvent free mechanochemical Grignard reaction. Patrick Harmon, Cole Sanchez, Jennifer A. Carroll 1. California Polytechnic State University - San Luis Obispo While pivotal to the field of organic chemistry as one of the few carbon-carbon bond forming reactions, the traditional method of Grignard reagent synthesis has disadvantages. One main shortcoming is the use of anhydrous diethyl ether as a solvent which is a known neurotoxin, forms dangerous peroxides, and is highly flammable. Recent literature in the use of mechanochemistry in Grignard reactions suggests a more safe and cost-effective synthesis. In this work, the tertiary alcohol, 1,1-diphenylpropan-1-ol was synthesized via a ball mill grinder without the use of anhydrous diethyl ether. The final product was characterized by both infrared and nuclear magnetic resonance spectroscopy. This indicates a successful alternative to the long-established method of running Grignard reactions. The complete results of the synthesis will be presented. |
Daphne Mood1★§, Brent Boone1§, Kel Mussetter2§, Emily Bockmon1†§1 Department of Chemistry and Biochemistry, 2 Department of Biological Sciences, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerPreserving seawater with mercury (II) chloride (HgCl$_2$) is the standard procedure for discrete carbonate chemistry sampling to halt biological activity and eliminate any resulting change in seawater chemistry. However, the innate toxicity of this compound has raised concerns about the safety of using mercury as a preservation tool, and especially when using HgCl$_2$ in the field. Additionally, in estuarine systems there is the possibility of mercury complexation changing the composition of the sample and impacting the value of total alkalinity. As a result, scientists may forgo preservation with HgCl$_2$ or delay the addition until it can be done safely in a fume hood. To quantify these effects, we investigated the acceptable length of time before preserving estuarine samples and the impact of mercury addition. Samples were collected across varying seasons and seawater conditions from Morro Bay Estuary, then were analyzed spectrophotometrically for pH and using an acid titration for total alkalinity. Measurable changes to seawater pH were identified beginning at four hours when unpreserved. Total alkalinity was found to decrease substantially in organic-rich estuarine creek waters due to the addition of HgCl$_2$ and filtration also decreased total alkalinity by removing inorganic carbon containing particles. These results indicate the need for specific considerations when sampling in estuarine systems and modification to the standard sampling protocols for total alkalinity. |
Franklin Ng1★, Trevor Cardinal2, Philip Costanzo11 Department of Chemistry and Biochemistry, 2 Biomedical Engineering, ★SpeakerPeripheral Artery Disease (PAD) is a vascular disease characterized by a buildup of plaque occluding the peripheral arteries, interrupting blood flow to downstream tissue. PAD currently affects an estimated 200 million people, and severe cases of PAD are the leading cause of amputation in the US. While there are modern surgical procedures that can restore blood flow to affected arteries, these methods pose major health concerns for half of affected patients. Given the significant demographic of patients lacking treatment options, there is a clear demand for a new method of treatment. A therapeutic target for PAD is expanding collaterals, smaller blood vessels that can grow to compensate for loss of blood flow caused by the occlusion of larger blood vessels, a process known as arteriogenesis. Myoblasts, muscle progenitor cells shown to promote arteriogenesis, are studied for their effectiveness as a cell therapy to stimulate arteriogenesis. Myoblasts are delivered using Poly(N-isopropylacrylamide) (pNIPAM), a thermo-responsive polymer that transitions from liquid-like to a solid-like form at body temperature to inject myoblasts in a target area. Due to a lack of methods to obtain quantitative data of the polymer construct, development of characterization methods began, starting with quantifying cell viability using a bioluminescence assay. |
Brenna Bradfield★, Addison Sampietro★, Scott EagonDepartment of Chemistry and Biochemistry, ★SpeakerLeishmaniasis is a disease caused by several Leishmania parasites and transmitted by infected female phlebotomine sandflies. The most prevalent disease types include the disfiguring cutaneous and mucocutaneous forms, and the visceral form, which is fatal if untreated. Leishmaniasis is considered a neglected global infectious disease and it is estimated that 700,000 to 1 million new infections occur each year. Currently, the only available drugs used to treat Leishmaniasis are very toxic, present severe side effects, and have declining efficacy due to resistance. Our poster will discuss the discovery of a new class of isoflavone-based antileishmanials and our current synthetic work to prepare a library of these new potential therapeutics. |
Salvatore Deguara†★, Ishita Patel★, Scott EagonDepartment of Chemistry and Biochemistry, †Frost Support, ★SpeakerCathepsin B is a cysteine protease that is found in the lysosomes of animal cells and proper activity of cathepsin B is essential for normal biological functions. However, both Anthrax and the Ebola virus exploit this protein during the infection process. Anthrax produces a protein that is not toxic until a portion of the protein is cleaved by cathepsin B, initiating a cascade that ultimately results in cell death. Ebola proceeds through a similar mechanism in that it requires the action of cathepsin B to activate a protein that is essential to the mechanism of viral replication. Thus, by targeting cathepsin B, we hope both diseases may be treated without relying on pathogen-specific methods. |
Abby McQuaid†★, Ian Hutt★, Victor Sepulveda★, Audrey Beaver★, Scott EagonDepartment of Chemistry and Biochemistry, †Frost Support, ★SpeakerUrinary tract infections (UTIs) are one of the most common bacterial infections caused by Uropathogenic Escherichia coli (UPEC), with approximately 10.5 million annual cases in the United States alone. UTIs are fairly ubiquitous in the clinic with about 50% of women suffering at least one infection episode in their lifetime. Moreover, approximately one third of those previously infected will experience a reoccurrence of the infection. Antibiotics have been effective at treating UTI, but their effectiveness is waning due to the surging resistance to antibiotics in causative bacteria. Our goal is to prevent the uptake of iron by UPEC by inhibiting TonB, an iron transport protein which is critical to E. coli survival in iron deficient environments such as the urinary tract. This treatment method is expected to leave beneficial E.coli strains in other regions of the body like the gut unharmed. Moreover, there is no TonB homolog found in humans, reducing the possibility of toxic side effects. |
Slade Schemmer★, Adam Ordaz★, Katherine Le★, Justin Wang★, Scott EagonDepartment of Chemistry and Biochemistry, ★SpeakerWe report the synthesis of a benzoxazole compound that targets the kinase protein CK2 (Casein Kinase 2). CK2 is a serine-threonine kinase that is ubiquitously expressed in all tissues and is known to phosphorylate more than 700 different residues. CK2 is also known to be upregulated in a number of cancers. By developing a procedure for the synthesis of drugs targeting this kinase, we hope to develop a library of potent and selective compounds that can later be screened as potential treatments for CK2-associated cancers. |
Hannah Negri†★, Leslie HamachiDepartment of Chemistry and Biochemistry, †Frost Support, ★SpeakerNetwork polymers are thermosets which are a non-recyclable class of polymer. They are non-recyclable because the long polymer chains are covalently crosslinked. Isocyanurates are a common cross-link in things like foams, varnishes, and paints. Our goal of dynamic covalent bonding is to use covalent bonds' capability of exchanging between molecules to allow for reprocessing of materials while maintaining important characteristics under thermal stimuli. Usually the cross links are permanent, and we want to make them reversible and dynamic. We do this by performing small molecule studies where we synthesize isocyanurates and attempt to optimize conditions for functional group exchange. Preliminary results demonstrated exchange, but further quantization has encountered obstacles. Developing covalent adaptable networks using isocyanurates would improve recyclability and benefit the environment by reducing non-biodegradable polymer waste. |
Mateo Wolfe1★, Elle Fishwick2★, Kate Morris1★, Carson Hasselbrink11 Department of Chemistry and Biochemistry, 2 Department of Biological Sciences, ★SpeakerXe-129 Hyperpolarized Chemical Exchange Saturation Transfer (HyperCEST) MRI is an imaging technique that utilizes xenon gas and chemical contrast agent used to bind the xenon. Organic macrocycles have been the typical class of molecules used for contrast agents; however, these candidates still have various issues that prevent them from reaching clinical use. Cyptophanes and cucurbriturils have shown HyperCEST effect and biocompatibility, but they remain difficult to synthesize and functionalize to biological tags. This project focuses on the macrocycle Noria-trisresorcinarene (R3) and its synthetic derivatives as contrast agents. R3 has shown promise for its strong HyperCEST effect with Xe-129, and thus, a linker molecule has been designed to covalently attach the macrocycle to a biological affinity tag, such as an antibody. These biosensor molecules will be utilized for targeted clinical imaging for the detection of breast cancer tissue. |
Finn Butler★, Madison Hathaway★, Joshua Giuliani★, Colin Thompson, Micheal HeyingDepartment of Chemistry and Biochemistry, ★SpeakerFermentation has been used for hundreds of years as a technique to preserve food while also facilitating a variety of changes to the product being fermented. The fermentation of wort, the starting material used to make beer, follows a highly complex, multi-step reaction mechanism in which yeast added to nutrient-rich wort facilitates changes in this starting material to produce by-products including ethanol, diacetyl, and 2,3-pentanedione. Due to the intricacies of this reaction, it is difficult to accurately predict the final alcohol by volume (ABV) and other characteristics of the end product. Instead, the fermentation reaction is simplified to yeast producing ethanol and other compounds while the yeast also reproduces and dies off, allowing a more predictive model to be made. These simpler models can then be generalized in attempts to predict the end ABV of different strains of yeast fermentation on their own. Once a model can be applied to a single strain of yeast, it is hypothesized that said model can be expanded to apply to a fermentation that uses a mixture of multiple strains of yeast, allowing for a greater understanding of the kinetic parameters. The hypothesis and predictive models' robustness can be determined by comparing them to generated experimental results across multiple different trials and yeast mixture percentages. |
Kay Herlihy1†★, Emma Langworthy2†★, Sophia Yurchenko2†★, Eva Voss1†★, Arianna Ortiz1†★, Kaitlyn Hand1†★, Eric Kantorowski1†1 Department of Chemistry and Biochemistry, 2 Department of Biological Sciences, †Frost Support, ★SpeakerOur research is focused on determining ring-opening regioselectivity of benzofused 1-arylbicyclo[n.1.0]alkane derivatives. Cyclopropanes are highly strained structures frequently used in drug development. Understanding their reactivity improves their reliable application in organic chemistry research. Our studies aim to understand how varying the ring size (n) influences the rate and direction of bond fragmentation. The target cyclopropane derivatives can be prepared by a four-step synthetic pathway. Heating these compounds in acidic conditions (AcOH, pTsOH, or HCl) induces the ring opening. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (NMR) are the primary instrumentation tools for following the ring opening reaction. Our analyses track reaction progress over time and determine major and minor products for each reaction. The goal of the investigation is to optimize the conditions for these ring-opening reactions and to exercise control over the direction of fragmentation. |
River Dolan★, Gabbi Hartmann★, Emily Satterthwaite★, Eric KantorowskiDepartment of Chemistry and Biochemistry, ★SpeakerThe hydroboration-oxidation reaction is a cornerstone reaction in the world of organic synthesis for its regioselectivity of placing an alcohol on the anti-Markovnikov position of an alkene. This makes it a necessary reaction in undergraduate organic chemistry curriculum. We propose a new hydroboration-oxidation reaction for organic chemistry teaching labs that puts more focus on the mechanistic possibilities of the reaction at high temperatures. Using allylbenzene, we showcase during the hydroboration step at 162$^o$C that higher temperatures allows for reversibility of addition and access to all positions along the alkyl chain. This reaction is followed via Gas Chromatography Mass Spectrometry (GC-MS) to see the rate of formation of all 3 products and determine the final percent composition of each product. This experiment allows for students to expand their understanding of the hydroboration-oxidation mechanism and gain experience with more complex reaction procedures and GC-MS analysis. |
Evelyn Jaminet★, Katy Byron★, Joanna LairdDepartment of Chemistry and Biochemistry, ★SpeakerMonitoring cellular migration is critical for understanding the development of diseases and immune function. One way to effectively track cells utilizes an "off the shelf" bioluminescent probe, a bioluminescent enzyme that can be added directly to the cell surface without the need for genetic encoding. This study aimed to synthesize a fluorescent probe to test a sortase-mediated labeling mechanism for attachment of our bioluminescent probe to the cell surface. A rhodamine probe with three glycines was organically synthesized and covalently bonded to the bioluminescent enzyme, NanoLuciferase using bacterially-expressed sortase A. The success of the reaction was determined by SDS-PAGE gel. In vivo testing is on-going to determine the efficacy of this attachment strategy for cellular monitoring. |
Alyssa Pama★, Christy Liao★, Ulises Frick, Andres MartinezDepartment of Chemistry and Biochemistry, ★SpeakerMicrofluidic paper-based analytical devices, also known as microPADS, are small, inexpensive and portable devices that can be used to manipulate and analyze small volumes of fluid. MicroPADs have potential applications ranging from point-of-care (POC) medical diagnostics to environmental monitoring. A standard approach for signal generation and amplification on microPADs is the use of enzymes and chromogenic substrates, which produce colored products and enable the qualitative and quantitative detection of analytes. A significant limitation to this approach is that enzymes are unstable on microPADs and degrade on the devices over time leading to poor performance. POC diagnostic devices with a short shelf-life are not ideal for use in resource-limited areas because continuously replacing expired diagnostic devices can be costly and is unsustainable for many areas. To address this issue, compounds with potential enzyme-stabilizing properties were systematically evaluated and compared on microPADs to determine the best stabilizer formulations. Bovine serum albumin (BSA) and sucralose were found to be effective stabilizers of the enzyme horseradish peroxidase. The results of this work will facilitate the development of shelf-stable microPADs suitable for global use. |
Cameron Causey★, Erik SapperDepartment of Chemistry and Biochemistry, ★SpeakerThe goal of service life prediction is to accurately predict the useful lifetime of a coating system in a typical service environment. Field testing is the most true-to-life form of service life testing but requires long exposure times, often not quick enough to readily aid redesign in the product development cycle. As an alternative, accelerated weathering chambers are used to speed up coating failure in a laboratory setting. These devices do indeed accelerate failure, but often produce failure modes that are not seen in actual service or produce material rankings that are not reproducible. This work explores the principle of cumulative stressor damage for an exterior architectural coating being exposed to outdoor conditions in San Luis Obispo, California, as well as an accelerated UV/moisture protocol. The accelerated UV/moisture protocol is executed first by ASTM D4587, and then by creating a custom exposure test cycle based on locally observed weather. Comparison of failure mode and quantification of failure is determined by gloss and spectral reflectance measurements. Finally, acceleration factor determination for the new SLO-in-a-box protocol is outlined, with a discussion of preliminary results. |
Zacharie Danega★, Olivia Everitt★, Simran Singh★, Lia Roccucci, Erik Sapper, Ray FernandoDepartment of Chemistry and Biochemistry, ★SpeakerDue to the heightened awareness on global warming and ever rising energy costs, there is a need to extend solar reflective technologies beyond roofs and pavements to other surfaces such as exterior walls. The initial focus of this study is to understand and quantify the heat reflective performance of conventional exterior architectural coatings and optimize such formulations for solar reflectance, without the use of specialty heat reflective materials. The optimized formulations are then used to quantify the enhancement of solar reflectance when formulated with commercial materials such as hollow-spherical inorganic and organic particulate fillers that are designed for this this purpose. In addition to solar reflectance, other key properties of the coatings both at wet state and as dry films are monitored. Results of this research should enable formulators to select solar reflective materials that will allow retention of important coating properties while providing the benefit of solar reflectance. |
Miles Brockman★, Zoe Bryan★, Wyatt Goldman★, Tristan Strom★, Erik SapperDepartment of Chemistry and Biochemistry, ★SpeakerVolatile organic compounds (VOCs) are evaporative molecules that react with nitrogen oxides in the atmosphere to produce tropospheric ozone. Increased tropospheric ozone levels result in smog pollution and respiratory issues. Even worse, some VOCs are recognized as hazardous air pollutants (HAPs) which can cause more severe health issues, reproductive effects, or birth defects. Chromatography methods existing for measuring the VOC content in commercial products such as paints and cleansing solutions. However, standard chromatographic methods do not assess how VOCs exit a polymer matrix that is slowly evolving, for example a crosslinking film that is curing on a substrate while simultaneously off-gassing volatiles. This study combines quantitative structure-property relationship modeling with hierarchical diffusion and transport studies to arrive at a better understanding of small molecule volatility in polymer matrices. Successful development and implementation of these models will enable novel material development that offers improved performance while also following current best practices of environmental stewardship and public health policy awareness. |
Ava Sanderson★, Katharine Watts†Department of Chemistry and Biochemistry, †Frost Support, ★SpeakerCarfilzomib is a synthetically produced multiple myeloma therapeutic with a structure derived from the proteosome inhibitor Epoxomicin, found in Actinobacteria. It is hypothesized that if the Epoxomicin biosynthetic pathway is deconstructed and altered, YU-101 - a Carfilzomib precursor - can be produced as a natural product, an approach that would decrease drug costs for patients. The Epoxomicin pathway is a three-gene cluster, the first of which encodes for the Non-Ribosomal Peptide Synthetase (NRPS) that synthesizes the tetrapeptide backbone of Epoxomicin. By expressing the four NRPS modular proteins individually, the three catalytic domains can be modified and analyzed. Since the Adenylation Domain determines the amino acids incorporated into the Epoxomicin backbone, modification of this catalytic domain allows for changes to the amino acid specificity of each NRPS. While expressing each NRPS module individually the modified amino acid specificity, retention of activity, and the ability of recombined NRPS modules to synthesize the modified Epoxomicin backbone must be monitored. To assess enzyme activity, an Adenylation assay has been developed to monitor the selectivity of each NRPS for the amino acid it is specific for. The adenylation reaction is catalyzed in-vitro, and a coupled Pyrophosphate (PPi)/NADH detection assay has been developed where PPi production is linked to the oxidation of NADH, a process observable spectroscopically. To determine if NRPS modules can communicate, a second assay has been developed. Since the NRPS protein has been separated into modules, communication domains have been installed on each module to facilitate recombinant peptide formation. The Product Formation assay combines NRPS modules with the amino acids they are specific for in-vitro, with dipeptide formation observed via HPLC. Each assay's effectiveness is currently demonstrated through analysis of previously characterized NRPS modules Gramicidin S Synthetase (GrsA) and Tyrocidine synthetase 1 (TycB1). |
Chris Cummings★, Samuel Catania★, Katharine WattsDepartment of Chemistry and Biochemistry, ★SpeakerEpoxomicin is a natural proteasome inhibitor and the structural inspiration for the multiple myeloma drug Carfilzomib. While Carfilzomib is produced through chemical synthesis, epoxomicin is produced by Actinobacteria in nature via a biosynthetic pathway including a nonribosomal peptide synthetase (NRPS). NRPSs are massive modular enzymes used by bacteria to build anticancer, antibiotic, and other bioactive peptides in an assembly-line fashion. By modifying the gene sequence of the epoxomicin NRPS and expressing the engineered enzymes in E. coli, we propose that the pharmacophore of Carfilzomib can be created biosynthetically, hopefully lowering cost and increasing efficiency. To express the large (>150 KDa) engineered NRPS enzymes in E. coli, we tested protein overexpression under the control of three different inducible promoters (araBAD, T7, trc). Plasmids were cloned via Gibson Assembly containing NRPS-encoding genes with each of the promoters, and transformed into BAP1, a derivative of E. coli BL21 . Some cloning work was done by students in a molecular biology lab course in an experiment-based independent project. Students took the same pre- and post-questionnaire to determine their understanding of molecular cloning concepts, terms, and techniques before and after the project. Both conceptual questions and attitudinal questions showed statistically significant increases. Protein expression tests were analyzed via SDS-PAGE and Western Blot to compare expression of NRPS enzymes in terms of inducer control and amount of overexpression. We found loose inducer control of expression in multiple vectors, even those under control of the arabinose operon. Additionally, high titers of full-length protein were correlated with expression of other protein fragments. With optimized expression, we will purify these enzymes and test their ability to biochemically produce the Carfilzomib pharmacophore. Continued optimization of modular protein expression and purification in E. coli can provide new insight on natural product bioengineering in a heterologous host. |
Tamara Nadjsombati1★, Kent Kashiyama1★, Katrina Culman2★, Steven Wilkinson11 Department of Chemistry and Biochemistry, 2 Department of Biological Sciences, ★SpeakerMultiple antibiotic resistance regulator (MarR) family proteins are commonly found in bacteria and archaea where they serve as transcriptional regulators of the expression of a variety of genes, including antibiotic resistance genes. They largely serve as repressors when bound to the promoter region and are responsive to natural ligands which modulate the affinity of the MarR homolog for its cognate DNA site. While much is known, biochemically, in regards to the DNA-binding properties of MarR proteins, less is known in regards to the structures of these interactions, and even less is known about the thermodynamics of these binding interactions. We are investigating two well studied MarR proteins: HucR from Deinococcus radiodurans, and MarR from Escherichia coli to determine the thermodynamics of the binding interactions of these proteins with their respective DNA sequences. Electrophoretic mobility shift assays (EMSA) were performed to measure the dissociation constant (Kd) of the protein-DNA binding interactions and to optimize buffer conditions for isothermal titration calorimetry (ITC). ITC is being used to determine the thermodynamic parameters, such as change in enthalpy ($\Delta$H), entropy ($\Delta$S), and free energy ($\Delta$G) of MarR protein binding to DNA. Ultimately, this information will be used in combination with structural analyses to build a comprehensive structural and energetic description of these protein-DNA interactions. |
Jason Lin†★, Emily Stokes, Shanju ZhangDepartment of Chemistry and Biochemistry, †Frost Support, ★SpeakerConductive polymers offer high electrical conductivity due to conjugation of its chain or through inclusion of heteroatoms (often Nitrogen or Sulfur). However, conductive polymers have significantly worse mechanical properties compared to non-conducting polymers and lose much of their conductivity when mechanically deformed. Here, a novel approach was used in maintaining the conductivity while allowing mechanical deformation. An emulsion of known structural (co)polymers were used as a matrix in housing the conductive polymer with the amount added based on the emulsion solid content. The mechanical, thermal and conductive properties of the resulting composite were examined. |
Riya Nigudkar★, Kelsey Blechen★, Karalee Webb★, David Zigler, Taylor HaynesDepartment of Chemistry and Biochemistry, ★SpeakerThe excited electronic states of dithiocarboxylate salts have a higher state density than the better studied thiocarbonyl analogs, leading to questions about their relative photochemistry. The solution phase photochemistry of various dithiocarboxylate salts was investigated using a combination of electronic spectroscopy and structural characterization, including electronic absorption, femtosecond transient absorption, 1H- and 13C-NMR, mass spectrometry, IR, and EPR. The photochemical quantum yields were studied for a set of dithiocarboxylates under various conditions to understand the impact of each condition on the photochemistry of dithiocarboxylates. Substituent groups, solvent, excitation wavelength, and addition of reactive substrates all affect the photochemistry of dithiocarboxlates. |
Quinn Casey★, Riley O'Malley★, Clara McMahon†★, Jane Nakamura, Todd Dr. Hagobian†, Adam Dr. SealDepartment of Kinesiology and Public Health, †Frost Support, ★SpeakerBisphenol A (BPA) is a synthetic chemical used in consumer goods and is linked to Type 2 diabetes progression in observational studies. No experimental studies have examined whether BPA promotes reductions in peripheral insulin sensitivity. To determine the effects of oral BPA administration on peripheral insulin sensitivity. Forty non-habitually active, healthy adults completed a 2-day baseline energy balance diet low in bisphenols during which urine, blood, and peripheral insulin sensitivity (i.e., glucose infusion rate/steady-state plasma insulin) via 120 min euglycemic hyperinsulinemic clamp technique were assessed. Participants were then randomly assigned, in a double-blinded fashion, to a 4-day energy balance diet plus oral BPA administration at 50 ug/kg body weight (BPA-50) or 4-day energy balance diet plus oral placebo (PL) administration. Outcomes were reassessed using a repeated measures ANOVA adjusting for baseline sex, BMI, physical activity, and ethnicity. Results From baseline to 4-days, body weight was not significantly (P>0.05) different between PL and BPA-50. From baseline to 4-days, fasting blood glucose was not significantly (P > 0.05) different between PL and BPA-50. Compared to PL urine BPA was statistically significantly higher (P<0.05) following BPA-50. From baseline to 4-days, peripheral insulin sensitivity significantly (P=0.01) decreased in BPA-50 and remained stable in PL. Conclusion BPA administration decreased peripheral insulin sensitivity after four days. These data provide the first experimental evidence that BPA administration may increase Type 2 diabetes risk. Supported by American Diabetes Association grant #1-19-ICTS-044. |
Sarah Blankespoor1†★, Raji Kachana1★, Emily Robles1★, Alison Smith1★, Shin Liow1★, Kara Samaniego2, Christine Hackman1†, Beth Chance3, Joni Roberts11 Department of Kinesiology and Public Health, 2 Campus Health & Wellbeing, 3 Department of Statistics, †Frost Support, ★SpeakerThe safety of abortion is heavily questioned in the United States despite available evidence. Hypothetical pregnancy choice (the decision to obtain or not obtain an abortion in a hypothetical situation of unplanned pregnancy) is a minimally studied variable. This study aims to assess perceived safety of medication abortion (MAB) as a predictor for hypothetical pregnancy choice. An online survey was sent out to a stratified random sample of Cal Poly students in Spring 2023, which assessed perceived safety of MAB, hypothetical pregnancy choice, and demographics for students identifying as biological females. Of 257 participants, the majority responded they would have an abortion in the case of an unplanned pregnancy (73.2%) and considered MAB to be moderately to very safe (90.3%). Logistic regression analysis revealed that, after adjusting for political and religious affiliation, those with lower perceived safety of MAB were about 15 times as likely as those with higher perceived safety to say they would continue an unplanned pregnancy rather than have an abortion (OR: 15.12; 95% CI: 3.723, 61.23). Perceived safety of MAB may play a role in students' reproductive health decisions. Future research will explore additional implications of perceived safety and its association with other reproductive health behaviors. |
Alexander J Kappos1★, Jack B Reed1★, Maya Groh1★, Sofia Alvarez1★, Kara Samaniego2, Christine L Hackman1★, Joni K Roberts11 Department of Kinesiology and Public Health, 2 Campus Health and Wellbeing, ★SpeakerBackground: California Senate Bill 24 (SB24) is meant to increase access to reproductive healthcare, particularly medication abortion (MAB) on public college campuses in California. Understanding student perceptions of the implementation and implications of SB24 is essential for shaping policy, reproductive access, and public discourse. Purpose: The purpose of this research project is to explore student perceptions and experiences of SB24 and MAB at California Polytechnic State University, San Luis Obispo. Methods: Through recruiting in general education courses, snowball sampling, contacting previous participants, and Campus Health and Wellbeing's secure messaging service, we are in the process of conducting one-on-one qualitative interviews with biological males, biological females, and individuals who have received MAB at Cal Poly's Campus Health and Wellbeing. We aim to conduct between 40 and 60 interviews during Spring 2024. Results: We anticipate a better understanding of student perceptions and experiences about MAB services on campus. Discussion: This research project highlights the importance of considering diverse viewpoints and perceptions regarding SB24. Understanding student perceptions can aid in the implementation of policies that support students' reproductive health needs. |
Abby Armstrong★, Madi Shaffer★, Paige Rightmire, Nicole HagobianDepartment of Kinesiology and Public Health, ★SpeakerA wide body of literature has examined coaching effectiveness (United States Olympic $\&$ Paralympic Committee, 2020). Sport literature has studied the coach-athlete relationship's effect on athlete experience (Lafreniére, et al., 2011; Jowett $\&$ Cockerill, 2003). However, there is limited research examining how a coach's purpose affects the athlete's experience (Yukhymenko-Lescroast $\&$ Sharma, 2022; Yukhymenko-Lescroast, M.A., $\&$ Gilbert, W.D., 2021). By studying the coach's purpose, we can gain a deeper understanding into their intention for coaching and how that translates to their athlete's sport experience. Comparing the coach's purpose against the established 4C's of effective coaching - competence, confidence, connection, and character - can determine how well the coach's purpose aligns with the definition of quality coaching and additionally, how that impacts athletes (Côtè $\&$ Gilbert, 2009). We will be studying the coach's purpose and its alignment with the 4C's and the impact of an athlete's understanding of their coach's purpose on their experience in sport. We aim to understand the coach's purpose; how well the purpose aligns with the 4C's and if a higher alignment means a more positive athlete experience; and if athletes that understand their coach's purpose attain the outcomes of the 4C's (Côtè $\&$ Gilbert, 2009). High school athletes and coaches will be recruited from San Luis Obispo County high schools via email. Coaches and athletes will complete anonymous validated measures that assess coaching purpose and its relationship to the 4C's. Coaches will also report their coaching purpose in their own words. Athletes will be asked how well they understand their coach's purpose using a Likert scale and to summarize their belief of their coach's purpose. |
Katie Ylarregui†, Sarah KeadleDepartment of Kinesiology and Public Health, †Frost SupportPurpose: ACT24 is a web-based previous-day recall that provides domain-specific estimates of sedentary behavior (SB) and physical activity (PA). The present study examined the feasibility and sensitivity to the change of ACT24 within an intervention study designed to reduce recreational sedentary screen time (rSST). Methods: StandUPTV is an intervention that evaluated the efficacy of three theory-based strategies for reducing rSST among adults. Participants were sent two invitations to complete the ACT24 survey on random days within each of the assessment weeks (baseline, 8-, and 16-wks) and data was summarized into overall and domain-specific time in PA and SB. Results: Participants (N=110) had a mean (SD) age of 41 (11.7)y and BMI of 29.7 (7.8) kg/m2. 80 participants completed the 16-week assessment. At week 16, there was a significant reduction in rSST of 1.2 (0.75,1.65) h/day due to significant reductions in TV viewing (0.70 [0.33, 1.1] h/day), and internet/computer use was significantly lower (0.50 [0.18,0.80)h/day). Leisure time sitting and reading increased (0.31 [0.13,0.49] h/day). Discussion: ACT24 was sensitive to changes in domains of SB that were the primary intervention target (i.e., rSST), and not in unrelated domains. Future research should compare the sensitivity of ACT24 to an objective measure of SB and examine whether there were differential changes in domain-specific PA and SB by intervention component within the optimization trial. |
Brendan Callender1★, Martin Hsu1★, Kirina Sirohi1★, Jadyn Ellis1★, Sarah Keadle2, Hunter Glanz1, Jonathan Ventura31 Department of Statistics, 2 Department of Kinesiology and Public Health, 3 Computer Science, ★SpeakerStep counting is an important measure of physical health that can be used to evaluate human activity and its relationship to cardiovascular health outcomes. Accelerometer-based wrist-worn devices are commonly used to track human activity by recording tri-axial accelerometer data to estimate steps taken throughout the day. In this study, we aim to improve the accuracy of an existing step-counting algorithm created by the UK Biobank. To serve as a benchmark for creating our own algorithm, we evaluated the accuracy of the UK Biobank algorithm compared to manually-counted steps. Adult participants (N=24) were video-recorded for two, 3-hour periods within their naturalistic environment while simultaneously wearing a wrist worn accelerometer. Posture, activity type and step counts were manually annotated by trained research assistants. Overall, the model performed well with a high correlation of 0.93 and a mean absolute percentage error of 19.6%. We found that the algorithm tended to underpredict steps during periods of modified walking (i.e. walking with load, ascending or descending stairs). For instances where the participants were walking with load, the algorithm incorrectly identified 40.6% as periods in which the participant was not walking, or had taken 0 steps. With an emphasis on improving step detection for periods of modified walking, we aim to develop our own step-counting algorithm using supervised machine learning and evaluate its effectiveness against the UK Biobank algorithm. |
Nicola Manalili★, Adrienne Lent, Julia AlberDepartment of Kinesiology and Public Health, ★SpeakerWhile Food and Drug Administration (FDA) approved medications for tobacco cessation are effective and available, they are often underutilized. The purpose of this study was to examine the association between identified barriers to accessing and reported use of FDA approved quit medications among a sample of San Luis Obispo County adults. An online survey (N =76) was conducted in March through September 2023. Logistic regression adjusted for demographic variables was used to examine how different factors (i.e. likelihood of quitting in the next month, contacting a healthcare provider about quitting, time since last healthcare visit, provider asking about tobacco/nicotine use, provider advice to quit, and provider prescription for quit medications) were associated with use of an FDA approved quit medication. Those with a high likelihood of quitting were less likely to report using a quit medication (OR = 0.14, 95% CI = 0.30, 0.73) while those who contacted a healthcare provider were more likely to report using a quit medication (OR = 15.39, 95% CI = 2.72, 87.05). While it was limited sample, there is evidence that more work is needed to encourage individuals who use tobacco products to contact their healthcare provider to support quit medication use. |
Mailee Sciocchetti★, Stefanee MauriceDepartment of Kinesiology and Public Health, ★SpeakerSport has always been a prevalent aspect of human history and has only become more popular worldwide. Understanding the factors influencing youth sports participation is essential for comprehending why children initially join sports. While parents and coaches often play a significant role in initiating participation (Danioni & Barni, 2019), research indicates that youth are primarily motivated by the enjoyment they derive from sports activities (Geidne et al., 2016). However, despite the emphasis on fun, the dropout rate remains alarmingly high, with approximately 30% of youth discontinuing at least one sport annually (Balish et al., 2014). Various factors contribute to this trend, including time constraints, academic pressures, and the demands imposed by parents and coaches (Fraser-Thomas et al., 2008). Moreover, the growing phenomenon of sports specialization poses additional challenges. Specialization, driven by the pursuit of competitive success, often leads to increased injury risk and burnout among young athletes (Campbell et al., 2021; Strachan & Deakin, 2009). As a result, many youths are forced to choose a single sport and commit to it excessively, compromising the enjoyment that initially motivated their participation. Therefore, understanding the motivations behind youth sports participation is crucial for redirecting the focus toward fostering enjoyment rather than solely prioritizing achievement (Gardner et al., 2017). The study interviewed 21 children aged 8 to 16 from roller hockey, soccer, and gymnastics, exploring their perception of fun and enjoyment in their respective sports. Through five questions, they discussed what they found fun and enjoyed about their sport. We found that children do not distinguish between fun and enjoyment but rather rope those two words together. Our results indicated five common themes that emerged: enjoyment stemmed from learning, competition, camaraderie, personal growth, and game-playing. This study highlights why children engage in sports and their perspective on fun. |
Rylie Lawrence★, Stefanee Maurice★Department of Kinesiology and Public Health, ★SpeakerThe role of physical therapists is to provide treatment and educational information to patients with the goal of recovery from injury and restoration of physical function. An important but understudied aspect of this care is psychological support. In this study, we will conduct semi-structured interviews with physical therapists and patients in two separate studies. These interviews will investigate how the social support of physical therapists is provided and its effect on the cognitive appraisal and perception of the rehabilitation process for physical therapy patients. Interviews with physical therapists will explore how they develop relationships with their patients, approaches to care with different types of patients, barriers faced, and their perspective on their role in providing support. Interviews with patients will examine their perception of the recovery experience, their relationship with the physical therapist, how they were supported during their care, and their expectations for their physical therapist. We will then use thematic analysis to identify themes in the physical therapists' and patients' experiences. The results and information from this study will identify different ways in which physical therapists support their patients throughout the rehabilitation process and in what ways patients find that helpful. |
Lindsey Fukushima★, Stefanee Maurice★Department of Kinesiology and Public Health, ★SpeakerReinjury Anxiety for Collegiate Athletes Maintaining physical, mental, social, and emotional health is important for everyone, especially collegiate athletes. However, when injuries occur, as they often do, athletes are put under pressure to rehabilitate and return to play at a quick rate and maintain the level of play that they were previously at. This and their attempt to balance their school work, athletics, and personal lives contribute to their increased stress levels. Reinjury anxiety, a predominant emotion associated with return to sport, is prevalent among many athletes following a sports injury. In this study, we will interview injured athletes from various sports teams at Cal Poly throughout their rehabilitation periods. We will take scores from multiple psychological surveys and use interviews to evaluate the relationship between perfectionism, athletic identity, and re injury anxiety. Another component of the interviews dives into the relationships between athletes and their coaches. These will reveal the impact of coaches on athletes' rehabilitation and which coaching methods/techniques athletes find most beneficial to their healing and return to sport. The results can be used to help healthcare practitioners and coaches guide injured athletes through their rehab and return to sport as they link pertinent psychological factors and coaching techniques to re-injury anxiety levels. |
Carson Crouch1★, Gavin Reed1★, Emma Davis1★, Safiya Rufino2★, Doris Cheung1★, Annie Hatzenbeler1, Annalise Vargas1, Brian Luu1, Darren Lin1, Olivia Wagner1, Sean Ryan1, Adam Seal1★1 Department of Kinesiology and Public Health, 2 Food Sciences, ★SpeakerThe global prevalence of chronic metabolic dysfunction and associated type II diabetes is increasing. Studies have shown that many factors contribute to developing type II diabetes, but none have shown if there is a direct correlation between hydration status and blood glucose. Using a randomized counterbalanced cross-over design, this study will compare the effect of high-water intake (HWI) vs. low-water intake (LWI) on blood glucose levels. Participants will be assigned to either the high-water intake group (3.7L for men, 3L for women) or the low-water intake group (1L for men, 0.7L for women) for 6 days. This will be followed by a 2-day washout period where they will drink as much water as they want. For the last 6 days, participants will complete the other condition. Participants will wear a continuous glucose monitor that collects data every 15 seconds. Urine will also be collected and analyzed for urine-specific gravity and daily volume. We hypothesize the group consuming the National Academy of Medicine's recommended water intake will have a lower blood glucose area under the curve (AUC) over 6 days. *Note* We are still collecting data for this project but we will have results by the conference date. |
Clara McMahon1†★, Riley O'Malley1★, Ethan Urbach1★, Brooke Latzke-Davis1, Zoe Maude2, Quinn Casey1, Logan Foster2, Mytam Le3, Tim Ibrahim1, Matthew Soran1, Adam Seal1, Todd Hagobian11 Department of Kinesiology and Public Health, 2 Department of Biological Sciences, 3 College of Engineering, †Frost Support, ★SpeakerPreviously non-exercising adults' adherence to exercise intervention studies is low, with only 50% meeting the national recommendations of 150 minutes/week after six months. A possible explanation of the low exercise adherence is that most interventions primarily use walking as the exercise. However, it remains unclear whether providing a variety of exercise modalities would increase adherence. This study aims to investigate the feasibility, adherence, and acceptability of various exercise interventions. Previously sedentary adults are randomized (by BMI, sex, ethnicity) to an unsupervised 1) walking intervention (control), 2) exercise variety intervention, or 3) exercise progressive intervention, for four weeks. In the exercise variety intervention, participants are prescribed a single different exercise regimen each week that includes cycling, walking/jogging, yoga/Pilates, and cross-training (kick boxing, karate, salsa dancing, circuit training) or strength training. In the exercise progressive intervention, the same exercises are included but each week get added one at a time into a growing list of options to choose from. Exercise levels are assessed by a physical activity log and accelerometry. Adherence rates will be compared across groups using a repeated measures ANOVA (group x time interaction) adjusting for BMI, ethinicity/race, income, sex, and age. |
Tori Blackburn★, Lena Demsky★, Kelsey Titterington, Adam SealDepartment of Kinesiology and Public Health, ★SpeakerBACKGROUND: The Oceano Dunes State Vehicular Recreation Area (ODSRVA) experiences an influx of hundreds of all-terrain vehicles that travel through daily during normal operations, driving sand and other small particulate matter into the air, ultimately decreasing the air quality of surrounding communities. Numerous studies have reported that exposure to poor air quality can adversely affect lung health. PURPOSE: This project aims to examine the effect of poor air quality on the prevalence of respiratory illnesses and lung function in adults residing in Oceano, Nipomo, and Grover Beach. METHODS: 571 participants were recruited using social media. An online survey was administered measuring respiratory health, physical activity, demographic information, proximity of residence to ODSVRA, and previous COVID-19 diagnoses. A multivariate regression was used to relate these factors to scores on a validated lung health questionnaire (St. George's Respiratory Questionnaire-SGRQ). RESULTS: Lung health was negatively associated with proximity to ODSRVA ($\beta$ = -0.37, p < 0.001), meaning the closer participants lived to ODSRVA, the poorer their lung health. Additionally, lung health was positively associated with education ($\beta$= 0.29, p < 0.001) and alcohol intake ($\beta$ = 0.37, p < 0.001). CONCLUSION: Residents of neighborhoods immediately surrounding ODSRVA have worse lung health compared to residents of similar neighborhoods located farther from ODSRVA. However, whether this is due to particulate matter driven in the air by recreational vehicles must be investigated further. |
Ali Willing1★, Jafra Thomas21 Department of Psychology and Child Development, 2 Department of Kinesiology and Public Health, ★SpeakerThe NFL's history includes the organization's fight against numerous lawsuits alleging excessive risk of brain injury to current and former players. We aimed to understand why, culturally, the NFL has 'failed' to avert serious harm alleged by the lawsuits, given the lawsuits' magnitude and the known brain-injury risks of playing tackle football. Using sociological theories (e.g., conflict/hegemony theory), the NFL's rhetoric towards safety concerns and recommendations for injury prevention were examined vis-a-vis qualitative analysis of its organizational and media practices (April to June 2023, Cal Poly undergrad course, KINE 324). Results showed that NFL personnel and putative experts promoted misinformation about brain injury risk (eg, pamphlets claiming players are not at serious risk of brain injury). Simultaneously, recurrent media practices, via glorified rhetoric, normalized over-conformity to a predominant sport ethic (eg, sacrifice physically, always strive to be better or risk being replaced). Organizational and media practices by, or endorsed by, the NFL culturally downplay or obscure the risk of brain deterioration from playing popularized forms of tackle football. Organizational and media practices by the NFL and others are a way to monetize conformity to a risky sport ethic. Future research into different vantage points and roles in sport is warranted. |
Yi Sheng Wu†★, Jasmine Wong†★, Jafra D. Thomas†Department of Kinesiology and Public Health, †Frost Support, ★SpeakerFew studies in kinesiology seem to report on the accessibility of survey tools before their use in research. The present study measured the accessibility of one survey website, created using Canvas, to test the comprehension of a mock physical activity promotion article written at two reading grade levels (11th and 8th grade, using the cloze procedure). Phase 1: The accessibility of the website's 10 webpages (e.g., site navigation) were rated with a valid and reliable rating form. Phase 2: after making edits based on rating form results, mock end-users (n = 12) tested the survey instrument and gave feedback on the website's usability. Ten gave feedback. Phase 1 analysis suggested most webpages (median = 80%) fully met accessibility standards. Phase 2 analysis supported most conclusions derived from rating form results (e.g., clear instructions & layout), but challenged others due to the website platform's inherent design limitations. Paradoxically, the 11th-grade material had higher comprehension, before the 8th-grade material was revised and retested in a follow-up pilot study. The findings suggest the rating form could support designing accessible research websites, but directly pilot testing instrument validity and functionality with mock end-users should not be overlooked. |
Jasmine C. Wong†★, Jafra D. Thomas†, Yi Sheng Wu†★Department of Kinesiology and Public Health, †Frost Support, ★SpeakerMost physical activity (PA) promotion materials written in English lack readability. To better train kinesiology students and others in lay communication, Thomas et al. (2023) developed mock online PA-advice articles written at two reading grade levels (RGLs)(8th and 11th). The present study further investigated the validity/reliability of the training materials by (a) analyzing their suitability beyond RGL (e.g. learning stimulation) and (b) by directly analyzing their comprehension in a sample of adult college students. The second author rated the materials' suitability using the adapted Suitability Assessment of Materials (SAM) protocol (Thomas et al., 2022), with almost perfect intra-rater reliability (i.e., 3-day grace period, Krippendorff's alpha-coefficient = .889 and .907, 11th & 8th RGL materials, respectively). The cloze-procedure was used to directly investigate comprehension through a pilot study (N=25, Thomas et al., in-press), testing 11th RGL material and two versions of the 8th RGL material. The original and revised 8th RGL material had higher SAM scores than the 11th RGL material, with the latter mirroring scores typical of online PA-advice articles. However before revision, the 8th RGL materials comprehension score was lower. We evidence the 11th RGL and revised 8th RGL material are valid/reliable mock materials. |
Camilo Vargas1★, Marilyn Tseng21 Department of Chemistry and Biochemistry, 2 Department of Kinesiology and Public Health, ★SpeakerThe COVID-19 pandemic has disproportionately impacted Hispanic/Latinx communities. This research investigates how Hispanic/Latinx individuals perceive their COVID-19 risk relative to other race/ethnic groups, and whether individuals with higher perceived risk engage in more preventive behaviors, such as mask-wearing, avoiding crowds, and limiting travel. We developed an online survey, available in both English and Spanish, that asked people to rate their risk of contracting COVID-19, rank COVID-19 risks for different racial groups, and report how frequently they engaged in mask wearing, avoiding crowds, and avoiding travel in 2021 and at the time of the survey. Recruitment took place both in person around shopping areas and online where participants were encouraged to refer a friend within the limits of Travis County (Austin), TX. 103 participants completed the survey. They ranged from 21-65 years, with 54% male. Highest level of education ranged from 8th grade (15.6%) to college graduate or higher (21.9%). Participants average perceived risk of contracting COVID-19 in the next month was 3.35 (0=not at all likely,10=very likely). In terms of preventive behaviors, 65%, 51%, and 32% of participants reported always wearing a mask, avoiding crowds, and avoiding travel during the pandemic, respectively. At the time of the survey, these percentages had decreased to 12%, 26%, and 22%. Our next steps are to conduct bivariate and multivariate analyses, which will guide us towards deeper understanding of how risk perceptions might affect preventive behaviors and contribute to COVID-19 disparities. |
Ashley Watt1★, Menna Street2, Anna Ostrander2, Marilyn Tseng11 Department of Kinesiology and Public Health, 2 Department of --Select--, ★SpeakerResidential environment affects health, and ethnic composition is an important characteristic of a residential environment. Past studies offer conflicting findings on whether living in areas with high co-ethnic density is positive or negative for cardiometabolic health. We conducted a literature synthesis to address this question: How does living in an area with others of the same ethnic group affect cardiometabolic risk in minority populations? We conducted a systematic literature search of articles published through September 2023 in Web of Science, Core Collection, and PubMed, using terms related to ethnic composition and cardiometabolic conditions (obesity, diabetes, cardiovascular disease). Articles were excluded if they were ecological studies, not original research, or not in English, or if they did not investigate neighborhood co-ethnic composition or a cardiometabolic risk outcome. Of 1,811 articles identified, 50 were eligible for inclusion. Of these, 35 included African Americans, 24 Hispanic/Latino populations, 12 Asians and/or Pacific Islanders, and two Native Americans. For African Americans (20 vs. 6 showing negative vs. positive impacts) and Native Americans (2 vs. 0), living in more co-ethnically dense areas was associated with worse cardiometabolic health. The opposite was true for Asians (1 vs. 5 negative vs. positive). Results were mixed for Latinx populations (9 vs. 6 negative vs. positive). Studies varied in terms of their design and measurement of independent and dependent variables. Thus, our next step will be to consider study quality in synthesizing their findings. Overall, findings from this literature review will clarify how the association of high co-ethnic density with cardiometabolic health differs by ethnic group, inform decisions regarding investments in neighborhoods, and identify remaining gaps in knowledge and directions for further work. |
Stephen Cook†★, Daniel Chamberlin†★, Parthiv Seetharaman†★, Hai Tri Tran†★, Vincent Bonini†Department of Mathematics, †Frost Support, ★SpeakerWe study a modified notion of Ollivier's Coarse Ricci Curvature on graphs that was first introduced by Lin, Lu, and Yau. In particular, we develop a sorting algorithm that constructs complete balanced bipartite subgraphs of certain Paley graphs and their generalizations. As a consequence, we are able to establish a global matching condition which results in an explicit formula for the Ricci curvature of certain Paley graphs and their generalizations. |
Madeleine Goertz†★, Elijah Guptill†★, Kelly Lyle†★, Eric BrusselDepartment of Mathematics, †Frost Support, ★SpeakerIn his Pillow Problems [2], Lewis Carroll asked, "what is the probability that a random triangle is obtuse?" Answering this question requires defining a "random" triangle, which many authors have explored [3, 4, 5]. We examine the geometry of the moduli space of similarity classes of triangles under three different classical similarity theorems: side- side-side, side-angle-side, and angle-angle-angle. Each theorem results in a topologically distinct moduli space: a 2-sphere [3, 4], Klein bottle, and Clifford torus of triangles [1], respectively, some of which appear in the literature. We contrast their group structures and how each theorem gives rise to distinct types of degenerate triangles. To answer Carroll's question, we put a metric and a uniform probability measure on each compact space. $$\newline$$ References [1] Brussel, E., and Goertz, M. E. (2023) The Torus of Triangles. arXiv:2303.11446. [2] Carroll, L. (1893) Curiosa Mathematica, Part II: Pillow Problems, MacMillan, London. [3] Edelman, A. and Strang, G. (2015) Random Triangle Theory with Geometry and Applications, Found. Comput. Math. 15 681-713, DOI 10.1007/s10208-015-9250-3. [4] Kendall, D.G. (1989) A Survey of the Statistical Theory of Shape, Stat. Sci. 4 87-120. [5] Portnoy, S. (1994) A Lewis Carroll Pillow Problem: Probability of an Obtuse Triangle, Stat. Sci. 9 279-284. |
Rapha Coutin★, Charles D. CampDepartment of Mathematics, ★SpeakerPleistocene records show that the Earth exhibits oscillatory transitions between periods of high and low global ice volumes, a behavior known as glacial cycles. A leading hypothesis posits that ice ages are paced by astronomical forcing; the glacial cycles we observe result from interactions between the external astronomical forcing and internal free oscillations in physical variables such as ice sheet volume, atmospheric CO2 concentration, ocean temperature, etc. Simple glacial cycle models typically take the form of fast-slow systems of a few key variables representing a subset of the major processes of the Earth's physical system. However, for such low-dimensional models to be realistic, they must be robust under the influence of stochastic noise, which represents the unmodeled fast processes. Before understanding the effect of noise on the insolation-forced system, it is useful to understand the influence of noise on the unforced deterministic models. An exploration of the effect of stochastic noise on common glacial models is given in Alexandrov et al. (2020). It is shown that stochastically forced trajectories are not always simply noisy versions of their deterministic counterparts. Behaviors arise in the stochastic world which have no analog in the deterministic. These behaviors are understood in relation to the geometry of the system nearby a bifurcation of the deterministic model. Reproductions of the work in Alexandrov et al. (2020) and applications of the methods given on a new model are done in this report, with an emphasis placed on understanding tools for analysis of stochastic models. A key distinction in response is made between models which have a mechanism for stochastic excitation and those which do not. |
Aria DeVries†★, Lucas Kantorowski†★, Elena DimitrovaDepartment of Mathematics, †Frost Support, ★SpeakerStatements such as "Modularity is a widespread property in biological systems. It implies that interactions occur mainly within groups of system elements," are common in the literature on molecular systems biology. However, no rigorous definition of "module" has been proposed that might be employed to gain either analytic or conceptual insights into the structure and dynamics of molecular networks. Our goal here is to introduce a method based on graph theory and community detection techniques that generates biologically meaningful modules in molecular networks and can be deployed to gain analytical and conceptual insights into the community structure and dynamics of a molecular network. |
David Wu†★, Khin Han†★, Vanessa Garcia Sanchez†★, Anton KaulDepartment of Mathematics, †Frost Support, ★SpeakerGeometric group theory is the study of the interplay between groups and geometry. By viewing a group as a metric space one can extract algebraic information. This is done by exploring the Cayley graph of the group, where it is given the standard edge-path metric. We explore a paper by James W. Cannon that introduces an algorithm that allows for efficient construction of Cayley graphs. In this project we will explore a class of groups, introduced by Cannon, known as Almost Convex groups. From this, there is an effective solution for the Word Problem (Dehn). |
Lily Adlin†★, Giovani Thai†★, Samuel Tiscareno†★, Ryan Tully-Doyle†★Department of Mathematics, †Frost Support, ★SpeakerGiven a self-adjoint matrix $A$ and a vector $\alpha$, the map \[ f(z) = \langle (A - z I)^{-1}\alpha,\alpha \rangle \] is an example of a so-called Nevanlinna representation or Cauchy transform, producing a rational self-map of the complex upper half plane. One interesting class of self-adjoint matrices that can be studied via this representation is adjacency matrices of simple undirected graphs. Given such a graph $G$ with adjacency matrix $A$, one can view the matrix $A - z I$ as the adjacency matrix of a graph that puts self-loops of weight $z$ onto the existing structure of $G$. In this case, certain choices of the vector $\alpha$ produce a rational inner function in the Pick class. We connect graph structures to the behavior of a two-variable analogue of the representation, which allows for more complicated boundary behavior to occur. The central matrix becomes $(A - zY - w(I - Y))$, where $Y$ is, for example, a diagonal matrix with diagonal entries $0$ and $1$. Reformulating these function-theoretic ideas in linear-algebraic terms provides straightforward arguments that extend known one-variable ideas about representations of certain graphs into two variables. We also look at the relationship between Bickel, Pascoe, and Sola's notion of contact order, which measures bunching of level curves of a representing function via power series, and the underlying graph. |
Deja Dominguez†★, Matthew Leibowitz†, Matt Beekman†★Department of Physics, †Frost Support, ★SpeakerWe present preliminary results from a comparison of quasi-adiabatic and quasi-isothermal Nernst coefficient measurements. The thermomagnetic material property known as the Nernst coefficient is of interest because it can reveal useful information about the charge carrier scattering mechanism(s) in semiconductors. Due to the presence of other thermomagnetic and thermoelectric effects that may be present under non-isothermal conditions in the transverse direction, the value obtained in the measurement of the Nernst coefficient can differ from its isothermal value, impacting the interpretation of experimental data. Since the currently available literature offers limited insights, we have begun an evaluation of different approaches for experimentally measuring the isothermal Nernst coefficient. We also discuss how the use of non-isothermal Nernst coefficient may impact the results in the analysis and interpretation of experimental thermomagnetic transport properties data. |
Kris Orszag★, Matt BeekmanDepartment of Physics, ★SpeakerWe are developing a simple and relatively inexpensive lab setup for the measurement of the temperature dependent molar heat capacity of solid samples. We use a calorimetric measurement in which we suspend a solid sample of known mass in liquid nitrogen vapor to achieve a desired initial temperature 77 K < T < 290 K, and then quickly immerse the sample in liquid nitrogen. Measurement of the mass of liquid nitrogen which was evaporated by the immersion of the sample at two different initial temperatures, along with a finite difference approximation, allows an estimate of the heat capacity at the average temperature to be determined. We have investigated multiple possible procedures, identifying potential sources of systematic error, to achieve a desired degree of accuracy in the measurement of the temperature dependent heat capacity. Results from experiments on elemental copper will be presented. |
Zoe Jackson Delos Angeles1★, William D. Cranney-Fee2★, Matt Beekman21 Department of Materials Engineering, 2 Department of Physics, ★SpeakerIntermetallic clathrates are materials that have crystalline frameworks with cage-like structures capable of encapsulating various guest atoms. The guest-framework interactions influence many properties of clathrates, especially the thermal and thermoelectric properties. To date, research on intermetallic clathrates has analyzed the effects of guest-framework interactions within limited compositions of clathrates. The goal of the present work is to conduct a comprehensive analysis of the published crystallographic data in the clathrate literature to understand how the framework responds to different guests and framework substituents. In this presentation, we report results on how different compositions in silicon-based clathrates affect the framework through analysis of the published crystallographic data, elucidating in particular how the framework responds to guests of different size. |
Sebastian Contreras1★, Raymond Remigio2, Elizabeth Johnson1, Samantha Allen1, Vardha N. Bennert1, Aaron Barth2, Vivian U2, Tommaso Treu31 Department of Physics, 2 University of California Irvine, 3 University of California Los Angeles, ★SpeakerIn the center of most massive galaxies is a supermassive black hole (SMBH) with a mass that can range from millions to billions of solar masses. It has been observed that more massive SMBHs have a more massive host galaxy bulge, as evidenced by the larger bulge luminosity and stellar velocity dispersion, a correlation known as the BH mass - host-galaxy scaling relation. It suggests a close evolutionary connection between the growth of the SMBH and the growth of its host galaxy. If a SMBH develops an accretion disk to fuel an active galactic nucleus (AGN), it will emit radiation across the electromagnetic spectrum. For broad-line AGNs, the mass of the SMBH can be determined using a technique called Reverberation Mapping (RM). In order to better understand the relationship between the mass of the SMBH and the characteristics of the galaxy it lives in, we are using GALFIT to analyze images of nine nearby RM AGN host galaxies taken by the Hubble Space Telescope. GALFIT performs 2-dimensional decompositions of the images, extracting the structural properties of the galaxy's components such as its bulge, disk, and bar if present. The first goal of this project is to determine the luminosity of each galaxy's bulge component to study the BH mass - host-galaxy scaling relation. The second goal is to determine the effective radii of the bulges to interpret the measurements of spatially-resolved stellar kinematics in these galaxies from Keck Observatory spectroscopic data. |
Julia Francescutti1★, Garrett Kunkler2★, Will Root3★, Phoebe Zyla1★, Jodi Christiansen11 Department of Physics, 2 Mechanical Engineering, 3 Aerospace Engineering, ★SpeakerVERITAS (Very Energetic Radiation Imaging Telescope Array System) is used for the detection of gamma ray photons (>100 GeV) arriving from outside the atmosphere, particularly from active galactic nuclei classified as blazars. When a high energy photon hits our atmosphere, it creates a particle shower. This shower produces blue Cherenkov radiation that is detected by our telescopes on the ground. We are analyzing the detected light from a set of blazar sources that were not known to produce very high energy gamma rays prior to our analysis. Our analysis has resulted in the discovery of source 1ES 1028+511, which was announced in January 2024. Several more of our sources are approaching and are expected to surpass the discovery threshold with the addition of more observations. |
Breanne Evans★, Alex Short★, Olivia Rourke★, Hudson Lazzara★, Jon FernslerDepartment of Physics, ★SpeakerThe dominant mechanism for molecular transport in biological systems, diffusion, has been described by Fick's law and Brownian motion for hundreds of years. However, recent research has measured non-equilibrium concentration fluctuations thousands of times larger than molecular length scales. This behavior is not predicted or expected by traditional models of diffusion and is theoretically attributed to coupling between diffusive mechanisms and fluid flow. These 'Giant Fluctuations' have been observed in shadowgraphs of three-dimensional fluids and are theorized to be significantly larger in two dimensions. The experiments presented here explore the diffusive mechanisms in quasi-2D fluids using freely-suspended liquid crystal films and Langmuir monolayers. Videos of both equilibrium and non-equilibrium diffusion are collected and analyzed through concentration correlation functions and structure factor functions to observe and quantify the theorized Giant Fluctuations. To observe Giant Fluctuations we will utilize fluorescence recovery after photobleaching (FRAP) to study non-equilibrium fluctuations in diffusion. FRAP experiments of dye mixed in freely suspended liquid crystal films can be repeatedly prepared with the same initial concentration gradient, and then compared to computer simulations. These experiments enable us to measure diffusion constants to quantify the range of length, intensity and time scales predicted for 2D fluid nonequilibrium fluctuations. A second method of observing the fluid-particle coupling behavior that is the believed cause of the giant fluctuations is through measuring and quantifying the fractal structures formed by nanoparticles aggregating in a quasi two-dimensional fluid. Videos of copper based quantum dots diffusing in smectic liquid crystal films are collected to measure quantities such as fractal dimension and aggregation rates. |
Dutch Foltz1★, Dane Kelly1★, Logan Tom2★, Victoria Dai2, Sam Weston2, Matthew Rydbeck1, Jonathan Fernsler1, Dean Arakaki21 Department of Physics, 2 Electrical Engineering, ★SpeakerIn search of a carbon-efficient alternative to fossil fuels, fat storages found in algae cells can be a potential source of fuel. Fuel sourced from algae results in a closed carbon loop where carbon dioxide released from burning the lipids is offset by that which is absorbed in the growth process. To access the lipids, we must rupture the cell wall using a process called lysis. To do this, we pulse an electric field across a sample of algae, called a Pulsed Electric Field (PEF). To perform PEF, we construct algae chambers with relatively large charged plates on each end. These chambers create voltage differences across the sample, and the pulsing of the created electric fields is regulated by a microcontroller. Our group has created two separate types of algae chambers. The first group, headed by Dutch Foltz, uses two 25mm by 25mm Indium Tin Oxide glass (ITO) plates to create a 30$\mu$m chamber width. The ITO slides allow for clear viewing of the algae during the lysis process, which we can do by putting it under a microscope and recording each PEF test we run. The second sub-group, headed by Dane Kelly, uses two five-by-five-inch stainless steel plates. The algae are placed in a quarter-millimeter gap in between the plates. This allows us to test larger samples, simplifying the application and removal of algae. We are hoping to use strategies from each method to understand how best to optimize and scale the process for potential application and fuel extraction. |
Reagen Garcia★, Thomas GutierrezDepartment of Physics, ★SpeakerThe CUORE (Cryogenic Underground Observatory for Rare Events) experiment is searching for neutrinoless double beta decay at the Gran Sasso National Laboratory. Neutrinos are currently treated as Dirac fermions, particles distinct from their antiparticles, making this decay forbidden in the Standard Model. However, observation of neutrinoless double beta decay would indicate neutrinos are Majorana fermions, particles that are their own antiparticle. CUORE currently sets the best lower limit on the half-life for neutrinoless double beta decay in Tellurium-130. CUPID (CUORE Upgrade with Particle Identification) is an experiment in development that will look for neutrinoless double beta decay in Molybdenum-100 at much higher sensitivity. Cal Poly is a member of these international collaborations and we will report on the status of these experiments. In addition we will report on possible methods to visualize Majorana and Dirac spinors in order to better understand the quantum mechanics of neutrinos that are their own antiparticle. This work was done in part with support from NSF-PHY-1913374. |
Aaron Friedman1★, Bryce McReynolds2★, Claire Olney2, Hilary Jacks2†1 MATE, 2 Department of Physics, †Frost Support, ★SpeakerSystems are said to have memory capacity if information can be written to them, read from them, and erased from them. Previous work has shown that disordered suspensions of particulates can retain memories of previously applied perturbation amplitudes. The canonical method for reading memories is problematic in that it (1) erases the memory upon reading, and (2) is computationally expensive. Via simulations, our group has developed an alternative reading method which avoids these issues. The work presented here describes student-designed instrumentation that will be used to write multiple memories along a programmable combination of x and y axes, and experimentally establish the efficacy of this new, more efficient method of reading memories from disordered particulate systems. Our physical apparatus includes a programmable 2D Helmholtz coil array that can oscillate a micron-scale ferromagnetic needle placed in the suspension; the motion of the needle can linearly and angularly shear the particulate suspension. The long-distance microscope system can record high-frequency time-series images. Particle density, position, orientation, and nearest-neighbor-distance data can be extracted from the images; analyses of these statistics versus perturbation parameters allow us to experimentally validate our efficient memory reading method. |
Zoe Chidambaram1★, Alex Garton2★, Jenny Kwak1, Max Varverakis1, Hilary Jacks1†1 Department of Physics, 2 MATE, †Frost Support, ★SpeakerKnit fabrics can store memories of their past; stretching out a favorite sweater will cause it to lose its shape and stretch differently until it is washed again. Measuring stress while cyclically straining knit fabrics produces hysteresis loops, which can be used to quantitatively describe a fabric's retention of past stretching. Nesting these hysteresis loops may allow for a fabric to store traces of multiple stretching amplitudes -- a phenomenon known as return-point memory. Additionally, knit fabrics can be used to model out-of-equilibrium disordered systems, which have robust memory capabilities. A fabric's structure may be tuned by altering these stitch statistics, enabling us to probe the role that statistical parameters play in the memory formation and retention of disordered systems. We have designed and built a device that measures a fabric's stress-strain over multiple cycles of programmable speed and amplitude. An Arduino Uno R3 is programmed to simultaneously 1) control a stepper motor that stretches the fabric and 2) record corresponding stress data from a load cell. Analyses of the stress-strain data produced by this custom-built instrument allow us to pursue multiple lines of inquiry at the cross-section of materials physics and memory. |
Irina Ivchenko†★, Colleen Marlow†Department of Physics, †Frost Support, ★SpeakerThe branching form of a plant's seedling root structure mirrors the many branching structures that occur in nature. Like a myriad of nature's networks, the structure of seedling roots is self-similar, or fractal. We propose that the fractal structure of seedling roots is optimized for their dominant function during this stage of the plant's life. To determine this, we aim to quantify naturally occurring seedling root structures with several appropriate metrics, such as fractal dimension and interaction volume. Next, we will computationally induce changes to the original seedling root structures, specifically to the weaving and forking angles of their branches. By comparing the changes (which occur under distortion) in the metrics that directly impact function to the fractal qualities of the overall structure, we aim to determine nature's optimized structure of seedling roots. |
Sofija Dimitrijevic★, Pasha TabatabaiDepartment of Physics, ★SpeakerThis study introduces a computational model based on the Vicsek model to simulate predator-prey dynamics emphasizing the field of vision of the predators and prey. Leveraging this two-dimensional agent-based model, we explore how the visual perception of predators influences their hunting efficiency and the spatial dynamics of prey populations. In our model, predators and prey are simulated as agents with distinct behaviors. Predators pursue the nearest prey within their field of vision, which is determined by a specified vision cone. Prey exhibit the canonical interaction rules associated with Vicsek style flocking while also evading predators within their own vision cone. This research contributes to our understanding of ecological dynamics by incorporating visual perception, an often overlooked factor in predator-prey models. |
Jonathan Hagendoorn★, Pasha TabatabaiDepartment of Physics, ★SpeakerFish groups move in complex, interesting ways. By experimentally confining small groups of fish within the lab and recording their movement over time, we hope to analyze the collective motions of these fish as something akin to a material. One method of describing traditional systems is by their thermodynamic properties, like the pressure. Here, we use a previously defined swim pressure for active matter systems to measure the swim pressure of a collection of fish. Ultimately, we want to understand if swim pressure is a useful metric for measuring system characteristics, and if we can externally control this property. |
Karen Severson★, Pasha TabatabaiDepartment of Physics, ★SpeakerThe Vicsek Model is a model that simulates the flocking behavior of particles and finds the phase transition from a disordered to an ordered state. Within this model, objects start with random orientations and positions, then as the model progresses and the objects begin to move, they try to align their orientations with their neighboring objects. For simplicity, this model assumes that all objects move with a uniform speed, irrespective of their orientation. However, in nature random variation is abundant and not all organisms move with the same speed. Here, we study the consequences of speed variation on the ability for groups to move collectively. |
Isabelle Cobb†★§, Ryan Walter†§Department of Physics, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerThe frequency, intensity, and duration of marine heatwaves (MHWs) have increased over the last several decades, threatening the health of marine ecosystems. However, eastern boundary upwelling systems (EBUS) have not observed the same trends and could act as thermal refugia in a warming planet. Moreover, MHW characterization in shallow nearshore environments in EBUS remains understudied due to the lack of long term in-situ measurements and issues with satellite retrievals near the coastline. In this study, we take advantage of temperature data from a very shallow nearshore site, a shelf-scale buoy, and offshore satellite-based measurements to examine spatial differences in coastal marine heatwaves in central California. We will report MHW metrics across interannual, seasonal, and individual event time scales across the sites, and link these results with upwelling wind forcing and basin-scale climate modes. Moreover, we will highlight the cross-shelf structure of MHWs and quantify a thermal refuge length-scale for the moderation of MHWs due to upwelling. In addition to a better understanding of patterns and drivers of coastal MHWs, these results can help improve predictive models and aid in the development of strategies to mitigate their impacts in the nearshore coastal ocean. |
Isabella Zadoyan1†★§, Ryan Walter1, Emily Bockmon21 Department of Physics, 2 Department of Chemistry and Biochemistry, †Frost Support, §Santa Rosa Creek Foundation Support, ★SpeakerSeagrass meadows are a critical estuarine habitat and have the potential to significantly modify both the physical and biogeochemical environment. We assessed the role of submerged seagrass meadows in modifying local hydrodynamics and subsequently creating localized microclimates with distinct biogeochemistry. We utilized physical and biogeochemical measurements inside and outside of a submerged eelgrass (Zostera marina) bed in the Morro Bay Estuary located in the mediterranean climate of central California. We found that the eelgrass beds generated significant drag (an order or magnitude reduction in the near-bed velocities) causing significantly less exposure to the warmer and slightly more saline back-bay water masses typical of the summer low-inflow dry season. Interestingly, we observed that inside the eelgrass beds, where photosynthesis is expected to dominate over respiration (leading to higher dissolved oxygen and pH), there were actually lower values of dissolved oxygen and pH overall, indicating higher levels of respiration inside the eelgrass beds compared to outside in the channel. However, the eelgrass beds did have higher dissolved oxygen and pH values during the early evening hours, in line with previous research highlighting the potential for ocean acidification and hypoxia amelioration. We will also investigate tidal phasing relative to the diel cycle, since the advection of water masses from different parts of the bay, and the modification of the transport of these water masses by the eelgrass beds themselves, can obscure biogeochemical comparisons. This work adds to a growing body of literature highlighting the importance of hydrodynamics in understanding the ability of seagrass beds to affect biogeochemical cycling and local mitigation of ocean acidification. |
Claire Gillaspie1★, Isabella Contreras1★, Jess Jensen21 Department of Liberal Studies, 2 School of Education, ★SpeakerAfter-school maker programs have the potential to foster STEM identities in youth. Through using simple or sophisticated technology, building meaningful relationships, and adopting mindsets that fuel creativity and inventiveness, students practice 21st century skills which enable them to imagine themselves as people who can do STEM. This mixed-methods study explores the affordances and limitations of resources (materials, relationships, and ideations) in the afterschool STEM maker program in support of youth identity development. Through the analysis of survey data and structural coding of student interviews, we compared how 3rd through 6th grade students' STEM identities were influenced after experiencing maker sessions guided by undergraduate facilitators. Our research found that our program had a positive impact on youth STEM identity development, which was most powerful when all three resources occurred in the same instance. Our presentation will discuss implications for practice that encourage STEM identity development, such as how to intentionally design makerspaces that provide students with purposeful resources, use language that reinforces STEM identity, and create student-centered spaces that encourage student leadership and reduce facilitator intervention. |
Behroozi Donya1★, Caesar Anabel2★, Salamatina Anna1★, Grant Billie-Jo11 Department of Statistics, 2 Department of Mathematics, ★SpeakerThis project examined how K-12 school districts in the United States prevent and respond to staff-to-student sexual misconduct from 2017-2021. Our team examined 4700+ documents related to adverse actions from the 500 largest school districts in the U.S., state level licensure actions from 29 states, 4,940 google alerts for teachers arrested documented in news media articles, and the cost of civil lawsuits against school districts from 450+ cases. Our research explored how districts handle cases of sexual misconduct and other violations of Title IX, revealing alarming patterns of teacher offenses being inadequately addressed and, in some cases, swept under the rug only to resurface in another district. School districts and state certification agencies were reluctant to provide records. Findings revealed that 67% of separation documents included purposefully ambiguous language and 85% of documents did not include the information requested. Further research is needed to explore the loopholes in the hiring, investigation and remedial action for staff who engage in sexual misconduct with students. |
Kendall Hipes★, Ben Laufer★, Beth ChanceDepartment of Statistics, ★SpeakerThe implementation of a fully online interactive textbook with integrated questions/solutions, applet visualizations, and software embedded into each lesson plan can provide support and convenience to an increasingly technology- and online-focused schooling. In particular, an interactive online textbook, integrated into the daily classroom activities as well, can provide students with alternative methods of learning and a more hands-on approach to learning than a more traditional textbook format. In this poster, we will discuss student responses on strengths and weaknesses of such a text used in two sections of Stat 301, Winter 2024, via an adapted version of the CourseKata platform (https://coursekata.org/). Throughout the quarter, students completed guided investigations and assignments all compiled into the CourseKata textbook platform in Canvas. Upon completion of the course, students were given an optional survey to provide feedback on the strengths and weaknesses of the textbook platform. From the information in this survey, data collected in the CourseKata platform, and insight from a series of focus groups (subject to IRB approval), we will evaluate the efficiency of the textbook and suggest areas for improvement. This feedback and further research will be considered when revisions of the textbook are made for later use, as well as whether or not we recommend applying this approach to other STEM-related courses. |
Visruth Srimath Kandali★, Beth ChanceDepartment of Statistics, ★SpeakerIn statistical practice, many procedures require the sampling distribution of means to be approximately normal. Most students learn a simplified check of this condition as "n >= 30"; often becoming a black-and-white mantra replacing visual inspection of the data. A slightly more detailed version might be "n >= 30 as long as the population distribution is not too skewed." Our research seeks to clarify a guideline that incorporates measures of skewness along with sample size. We will use simulation to explore the consequences of skewed populations with different sample sizes. We hope to provide students and practitioners with a slightly more refined rule that allows a way to operationalize the degree of skewness in statistical analysis, with implications for instructional practice. |
Alexander Arrieta1★, Nathan Hill2★, Soren Paetau3★, Hunter Glanz2, Jonathan Ventura11 Department of Computer Science, 2 Department of Statistics, 3 Department of Mathematics, ★SpeakerBoiling fuel in rockets raises many potential dangers. It would be greatly beneficial to determine the conditions inside of the fuel tanks in real time to mitigate the risks associated with boiling fuel. Boiling typically emits distinct audio signals that can be used to identify its exact stages and characteristics. However, detecting localized boiling inside a fuel tank presents numerous challenges due to the inability to gather data directly from inside the tank, instead relying on external sensors. We analyzed accelerometer data from an isolated experiment using several different methods to determine the most efficient way to categorize the data. The experimental setup varied to capture different possible boiling conditions within the tank and external noise. The studied methodologies ranged from simple mean shift testing to a convolutional neural network architecture. We found that there were several viable methods of change detection given the experimental data. However, due to a lack of variety in the available experimental data it is unclear if simpler methodologies will be effective in real life scenarios given the amount of background noise that could be expected and the wide range of possible scenarios. Still, our methodology has shown that it is possible to classify boiling within a fuel tank with over 90% accuracy despite the loss in data quality using external sensors. |
Jamie Luna1★, Rachel Roggenkemper2★, Matteo Shafer2★, Hunter Glanz2, Jonathan Ventura11 Computer Science and Software Engineering, 2 Department of Statistics, ★SpeakerHuman trafficking affects approximately 21 million victims and generates an estimated $50 billion in revenue for traffickers each year. Traffickers increasingly leverage internet-based applications to conduct their operations. And despite the enormity of this issue, less than 50,000 victims are identified annually. Global Emancipation Network (GEN), a 501(c)(3) aiming to disrupt human trafficking networks globally, used Meta AIs Segment Anything Model (SAM) and OpenAIs Contrastive Language-Image Pretraining (CLIP) model to predict the origin of a given photograph. We applied Zero Shot Instance Segmentation on top of this model to identify and label objects within the given photograph. Our work explains the predictions made by the SAM and CLIP models. This approach provides insight into how the location prediction was made and the influential factors in making that prediction. This approach allows victims to be identified and found more effectively, aiding GEN in their mission. |
Andrew Kerr1★, Aditi Gajjar1★, Cameron Stivers1★, Liam Quach1★, Hunter Glanz1, Jonathan Ventura21 Department of Statistics, 2 Computer Science, ★SpeakerTo effectively increase shared prosperity in Africa, World Bank, the largest source of funding and knowledge for low and middle-income countries, conducts projects aimed at improving digital systems. Yearly reports summarizing the effects of these projects are created to keep stakeholders informed, and share the impact of their efforts. However, given the complexity of the data, it is difficult to summarize the specific effects of the World Bank on Africa. We refined the classification of these projects into digital categories by utilizing the names of indicators, specific components of projects that contain vital data and outcomes. Leveraging two methods, a naive approach using keywords and a large language model approach, we aggregated the outcomes of similar projects, standardizing their units of measurement to produce a singular, comprehensible figure. These figures provide the World Bank a method to communicate its effect on Africa in a clear, concise, format. |
Lana Huynh★, Dylan Li★, Isabella McCarty★, Kyle Lew★, Hunter GlanzDepartment of Statistics, ★SpeakerPoverty estimation in the Middle East and North Africa (MENA) region faces significant data collection challenges because household surveys are often impractical due to government conflicts and resource constraints. Our project aims to determine if public geospatial information, when integrated with machine learning techniques, can provide a reliable alternative to traditional surveys by predicting poverty levels across MENA. The main challenge lies in balancing the tradeoff between enhancing spatial and temporal granularity and ensuring the model's accuracy and broad coverage. By exploring innovative methodologies, this study seeks to contribute valuable insights for poverty assessment and policy formulation in the MENA region. |
Edy Reynolds1★, Lauren Taylor1★, Payton Swanson2, Emily Robinson11 Department of Statistics, 2 Department of Liberal Studies, ★SpeakerFood insecurity remains a significant challenge in San Luis Obispo (SLO) County, with organizations like People's Kitchen at the forefront of providing meals to those in need. However, identifying trends in daily meal counts has proven difficult. This project aimed to digitally convert five years of paper records, develop a data workflow, and design an interactive dashboard to visualize meal count trends. We collaborated with People's Kitchen to digitize their records, creating a data workflow hosted on the Google Suite for accessibility and sustainability. Utilizing Google Forms for data entry and Looker Studio for visualization, we streamlined the process for board members, ensuring ease of use and understanding. The interactive dashboard provides a comprehensive view of meal count trends, highlighting annual changes, weekly summaries, factors influencing meal counts, and the impact of serving groups. By empowering People's Kitchen with actionable insights, they can better communicate their impact and make decisions for their organization. Our experience emphasized the importance of user experience and partnership with stakeholders. We are now exploring advanced visualization techniques using RShiny to enhance predictive modeling and decision-making capabilities. |
Dillon Murphy★, Susan VanderPlas, Heike Hofmann, Emily RobinsonDepartment of Statistics, ★Speaker'You Draw It' is a feature that allows users to interact with a chart directly by drawing a line on their computer screen with a mouse. Originally introduced by the New York Times in 2015 for the purpose of interactive reading, we aimed to adapt and demonstrate the use of the 'You Draw It' method as a tool for interactive testing of graphics. Last summer, I bundled the 'You Draw It' feature into an R package, added additional functionality to the tool, and created an accompanying shiny web application for users to easily use the package features outside of R. This enhancement not only streamlines its integration into various projects but also broadens its potential applications in data visualization and user engagement. My poster showcases the evolution and capabilities of the 'You Draw It' tool. |
Aditi Gajjar†★, Cameron Stivers†★, Kevin RossDepartment of Statistics, †Frost Support, ★SpeakerResponsive feeding occurs when caregivers respond to infant cues to determine feeding pace and duration. It is hypothesized that responsive feeding supports infant self-regulation and promotes healthy weight outcomes. Previous research suggests that mothers are more responsive to infants' receptiveness than disengagement. This study describes the variability in the cues exhibited by infants during feeding across the first year. 203 mother-infant dyads were assessed when infants were approximately 1, 2, 4, 6, 9, and 12 months of age. Dyads were recorded by video doing a typical bottle-feeding session. Trained coders masked to study hypotheses coded infant satiation cues and the responses from mothers to these cues. In this research, We used clustering methods to explore behavioral patterns by grouping feedings based on recorded baby and mother actions. Furthermore, we explored which behaviors are correlated with each other, and whether clusters and mother-infant interactions develop over time. |
Lily Cook†★, Gabby Low†★, Anelise Sabbag†Department of Statistics, †Frost Support, ★SpeakerVirtual learning has become a permanent part of education since the 2020 pandemic. Many courses are still offered asynchronously, hosted online with no set meeting times. A flexible schedule has many benefits but can create issues in building a collaborative learning environment, which is essential to effective education. Collaborative Keys are a pedagogical tool to help remedy the lack of collaboration in asynchronous classes by promoting group discussion and interaction. In this model, students individually respond to assigned questions, share their responses with a small group for discussion and come to a consensus on final answers. This project focuses on Cal Poly students in an introductory statistics course. Our research questions relate to student interactions within the Collaborative Keys, student performance, and changes throughout the quarter. The process started by confirming all student documents had consistent formatting to ensure clean data. To collect data, rubrics were create for each assignment, responses assessed and scores recorded. Additionally, indicator coding was conducted using variables involving key elements of the Community of Inquiry framework: Teaching Presence, Social Presence, and Cognitive Presence. Our results will inform pedagogical approaches that incorporate collaborative learning into virtual environments and improve students' experiences in asynchronous modes of instruction. |
Adelle Wilkin1†★, Sophie Short1†★, Maddie Schroth-Glanz2, Heather Liwanag31 Center for Coastal Marine Sciences, 2 Department of Statistics, 3 Department of Biological Sciences, †Frost Support, ★SpeakerUnderstanding and conserving ocean ecosystems is a difficult, but important task made easier with bioacoustic technology. Although marine mammal monitoring efforts can be achieved with visual surveys, they can be financially limiting and lack temporal information on a finer scale. Long-term passive acoustic monitoring efforts of critical migratory species can provide detailed information about the region's marine soundscape which is key to conservation efforts. Our project aims to establish a long-term bioacoustic monitoring station off the coast of central California and help close the gap in our understanding of marine mammal presence along the Pacific coastline. Marine mammals depend on the acoustic environment for survival, and an increasingly noisy ocean poses risks to the conservation of species that migrate through industrialized waters. The goals put forth by the bioacoustic lab for this academic year include (1) determining probable species presence, (2) ascertaining temporal (day/night) variations of vocalizations, and (3) examining key differences in species and call type between deployments in Fall 2022, Winter 2023 and Spring 2023. These comparisons are crucial to a baseline understanding of seasonal and temporal variations of our region's understudied soundscape. We anticipate humpback-dominated waters in Fall and Spring and have observed song in Fall 2022 and predict Gray Whale We aim to implement various long-term deployments to gather more complete and consistent bioacoustic data in our local waters. These deployments and the subsequent analysis will contribute to large-scale marine mammal monitoring and conservation efforts along the California central coast. |
Anagha Sikha★, Sucheen Sundaram★, Sophia Chung★, Maddie Schroth-Glanz, Hunter Glanz, Jonathan VenturaDepartment of Statistics, ★SpeakerPassive acoustic monitoring (PAM) for whales and other marine animals plays a pivotal role in understanding crucial aspects of their ecology, including distribution, abundance, habitat utilization, seasonal and long-term movement patterns, and vocal behavior, with implications extending to management and conservation initiatives. Students on the Marine Acoustics Research Team at Cal Poly, led by Maddie Schroth-Glanz, have spent many hours listening to underwater audio files and detecting and classifying animal sounds. To aid in this process, data science teams in the past worked on building a machine learning pipeline based on Monterey Bay hydrophone data to automatically detect marine animal noise based on these previously annotated data. Our research uses an ensemble of variational autoencoders to advance PAM along the Central Coast of California, particularly at the Cal Poly Pier in Avila Beach. Our model currently demonstrates a non-binary accuracy of 82% and precision of 12% in detecting marine sounds from the hydrophone recordings, showcasing the promising potential for further advancements in PAM methodologies. We hope our results will make detection advancements to understand further marine ecosystems and the impact of human activities on underwater habitats. |
Adam Del Rio†★, Emily Zhu†★, Ken Xie†★, Immanuel Williams†Department of Statistics, †Frost Support, ★SpeakerIn our pursuit to innovate data science and programming pedagogy, we aim to familiarize educators with API's pivotal role in data acquisition. This effort seeks to encourage instructors to seamlessly incorporate API calls and functions into their curricula, thereby catalyzing student curiosity in data exploration. APIs, often perceived as daunting, will be demystified, enabling educators to confidently integrate these tools and foster a learning environment where computer science techniques are harmoniously blended with statistical analysis. As data becomes increasingly central to our discourse, it is crucial for educators to adeptly navigate diverse data streams. This knowledge is not just an academic pursuit but a necessary skill set for the evolving landscape of data science. Our initiative aspires to equip educators with the competence to access expansive data repositories, enriching the educational experience and empowering the next generation of data scientists. |
Samantha Albiani1★§, Tatum Schneider2★, Uriel Figueroa1★§, Allysa Biddle1★§, Hailey Benson1★§, Greg Schwartz1★§1 BioResource and Agricultural Engineering, 2 Department of Biological Sciences, §Santa Rosa Creek Foundation Support, ★SpeakerAn artificial marine multitrophic recirculating aquaculture system was modified during the summer of 2023. Rockfish, Pacific Oysters, and seaweed (Ulva) were stocked in the system during the 23/24 academic year. Water temperature was maintained between 16 and 17C, salinity between 30-35 PPT, and pH between 8.4 and 8.6. Focus this year was on filtration and growth rates of the Pacific oyster and nutrient uptake and growth rates of the cultured seaweed Ulva. Over 150 oysters were individually marked and fed three times per week either live microalgae feed, a powdered diatom, or a fresh algae paste. Length, width, depth, and weight were measured for each individual every month (winter quarter). Two 250 liter tumble culture seaweed tanks were placed in the system. Each week growth rate data was collected, and the systems were reset to 1 gram seaweed wet weight per liter (winter quarter). Nutrient uptake rate was also collected but proved to be more difficult. Preliminary data will be used to determine the required biomass of each trophic species to have a balanced system and utilize waste nutrients from the fed finfish species, thus minimizing waste products leaving the system and entering the environment. |
Caroline Swanson★, Hadas Tankel★, Angelina Enriquez★, Sequoia Fricia★, Susana LopezPsychology, ★SpeakerThe purpose of the study is to gain insight into younger adults' worries surrounding Alzheimer's disease and other dementias to aid young adults with education about the disease and coping mechanisms to live life to the fullest before possibly acquiring the disease in the future. There is not much research looking into how Alzheimer's disease affects this age cohort, as most of the research is geared towards caregivers and Alzheimer's patients. Yet, dementia affects the whole family unit. Currently, 7 million Americans are living with Alzheimer's (Alzheimer's Association, 2024). With the population rate of people 65+ years of age growing, this number is expected to increase significantly in the next few decades. This research study has interviewed college students who have observed an Alzheimer's or dementia experience, whether that has been in their family or through volunteer work. Then, the qualitative interview transcripts will be analyzed with thematic analysis. Interviews conducted in January through March 2024 have examined the mental health effects of the disease and the participants' understanding of the disease. This will grasp both a psychological and public health lens by asking questions regarding participants' mental health surrounding their experience with the disease and attempt to understand their medical knowledge of dementia. It is expected that younger adults will desire more resources on how they can prevent Alzheimer's for themselves. The studies findings will be presented back to the Alzheimer's Association so they can better understand how to help the younger population affected by Alzheimer's disease. |
Gabriel Anderson1†★, Tony Cummings21 Department of Biological Sciences, 2 SIT, †Frost Support, ★SpeakerCoral reefs are experiencing more intense and frequent climate change-induced disturbances, such as cyclones and bleaching events. Robust forecasting of future ecological reef functioning requires that we 1) better document environmental conditions which stress these systems and 2) construct better models of the impact of such disturbances upon coral communities and their ability to recover from such stresses. From March of 2014 to May of 2017, the Lizard Island reefs in the northern region of the Great Barrier Reef experienced four consecutive disturbances; Cyclone Ita in 2014, Cyclone Nathan in 2015, and two massive bleaching events in 2016 and 2017. Between the intense patches of physical damage from the cyclones and the uniform impact of the bleaching events, these reefs were devastated, with none of the eight study sites reaching more than 20 percent coral cover by May of 2017 (Madin et al., 2018). In November of 2023, after six years of relatively calmer conditions with no conspicuous region-wide, large-scale disturbances, I documented the extant coral community on eight previously-monitored reefs around Lizard Island. All of these reefs showed significant (p<0.0001) improvement from their 2017 post-disturbance degradation. Living coral at my study sites had recovered to cover 18.4 to 59.9 percent per site in 2023, with many sites towards the higher end of that range. Recovery appeared to follow a north-south trend in which more Trade Wind-sheltered northerly sites had generally greater rates of recovery and total coral cover. Possible phase shifts at a select few southern sites exposed to more consistent wind-driven storms likely drove poorer recovery rates at those sites. Future annual surveys of the study sites as well as others surveyed in 2017 may better clarify the relationship between reef location and the rate of recovery of coral cover post-disturbance. |
Elisabeth Stodola1★, Trevor Cardinal21 Department of Biological Sciences, 2 Biomedical Engineering, ★SpeakerPeripheral Artery Disease (PAD) is a condition caused by a buildup of plaque in arteries that leads to ischemia in lower extremities. Despite implementation of revascularization procedures, many PAD patients have limbs amputated to prevent necrosis. An alternative involves promoting arteriogenesis of collateral vessels, forming natural bypasses around occluded arteries. Arteriogenesis is orchestrated by macrophages. It involves recruitment of monocytes that differentiate and polarize into an inflammatory M1 phenotype, responsible for secreting proinflammatory factors. These M1 macrophages then transition to a regenerative M2 phenotype, responsible for regeneration through paracrine signaling. The M1 to M2 switch promotes arteriogenesis, imperative for revascularization. In previous studies, it was found that in an in vitro coculture of RAW 264.7 macrophages and primary myoblasts, pre-polarized M0 (undifferentiated) and M1 macrophages demonstrate the switch towards M2 in 48 hours and have higher proliferation rates. This current study will explore classifications of different morphological stages of RAW 264.7 macrophages, driven by polarization factors and in the context of an in vitro coculture with primary myoblasts. Future studies will include the use of flow cytometry to perform a multi-parametric analysis of macrophages at different morphological stages. |
Logan Foster★, Clara McMahon★, Sura Sohi, Brooke Fujioka, Ethan Urbach, Zoe Maude, Amy Daseking, Bella Munoz, Danielle Mattson, Isaiah Martinez, Rhyane Caspers, Aziz Bassil, Kennedy Nelson, Tim Ibrahim, Shawdi Amini, Todd HagobianDepartment of --Select--, ★SpeakerMilitary personnel are frequently exposed to high altitudes, which decreases exercise performance. Few methods have been developed to mitigate the hypoxic effects on exercise performance. Previous studies have shown that creatine supplementation increased exercise performance at sea level. No experimental studies have examined creatine supplementation at simulated altitude. Objective: To determine the effects of creatine supplementation on exercise performance at simulated altitude. Methods: Sixty habitually active, healthy adults (30 M, 30 F; 18-40 yr) will be recruited from Cal Poly, and informed consent will be obtained. After an overnight fast, participants will complete a repeated sprint exercise test which involves six, 10-second sprints on a cycle ergometer with 60-second recovery between each sprint test. Participants will then be randomized in a double-blinded fashion to placebo or creatine supplementation (20g/day) for 2 days. After the 2-day supplementation treatment, participants will complete the repeated sprint exercise test while breathing a hypoxic gas mixture containing 12.8% oxygen (4000 m elevation). Outcomes measures are peak power (watts), relative peak power (watts/kg), mean power (watts), relative mean power (watts/kg), and fatigue index (watts/second). Summary: To our knowledge, this will be the first study to determine whether creatine supplementation can increase exercise performance at simulated altitude. |
Caitlin Robertson1★, Seeta Sistla21 Department of Biological Sciences, 2 Department of Natural Resources and Environmental Sciences, ★SpeakerAs utility-scale solar energy (USSE) becomes an increasingly popular green energy source, ecologists are investigating the environmental impacts of these developments. Studies have shown their potential to sequester carbon, support pollinators, or coexist with agricultural operations. However, few have studied the impact of USSE arrays on plant phenology and green-up patterns, which may illuminate how these developments impact the ecosystem services provided by plants under the arrays. In two USSE arrays located on degraded, arid grasslands, we measured the Normalized Difference Vegetation Index (NDVI, a proxy for greenness), phenological stage, and ground cover of paired under-panel and alley plots and reference plots outside of the array. Under-panel and alley areas have delayed green-up as compared to reference plots, showing significantly lower NDVI from January to April. During this period, reference areas also had significantly higher vegetative cover and species diversity than within the array. While under-panel areas were the most vegetatively depauperate, the difference between under-panel and alley areas did not significantly differ. It remains to be seen whether these patterns hold as the growing season progresses, but our initial findings highlight the potential for large-scale solar arrays to alter ecosystem phenology, changes that can feed back to affect higher trophic levels and processes such as pollinator dynamics. |