Digital Commons Network^™

Effects Of Cell-Free Supernatants Of Commercial Yogurt Products On Salmonella Survival, Juliet Durant, Akayla King

Student Posters

Salmonellosis remains a global public health challenge and Salmonella enterica serovar Enteritidis and Typhimurium are the primary causes. Salmonella virulence mechanisms involve attachment and invasion of intestinal epithelial cells. Gut microbiota and probiotics that contain Lactobacillus species have been shown to prevent Salmonella infection. Yogurt is a commonly consumed probiotic product containing Lactobacillus species. Yogurts made under laboratory conditions and the cell-free supernatants have been shown to inhibit Salmonella growth. The many commercial yogurt products on the market may vary in antimicrobial components based on production methods. Therefore, the present study aimed to evaluate the survival of 5 log CFU/mL …

Title: An Analysis Of Hmbs Variants Associated With Acute Intermittent Porphyria, Elaine Vanterpool, Jason Kahari

Student Posters

HMBS, also known as hydroxymethylbilane synthase, is a gene that is responsible for providing instructions for making the enzyme named hydroxymethylbilane synthase. This enzyme is involved in the creation of a molecule called heme. Heme plays an important part in all of the body’s vital organs. It is important to all organs however, it is most prevalent in the blood, bone marrow, and liver. Heme is essential in making iron-containing proteins called hemeproteins. To produce heme, an eight-step process must occur that requires 8 different enzymes. “Hydroxymethylbilane synthase is responsible for the third step in this process, which combines four …

The Association Of Abca3 Variants In Hypertension Pathogenesis, Elaine Vanterpool, Jea Joseph

Student Posters

Hypertension affects around 48.1% of people living in the United States. This number of adults with hypertension between the ages of 30-70 has increased from 650 million to 1.28 billion in the last 30 years. Hypertension is characterized as a condition that affects the arteries of the blood. High blood pressure and high cholesterol have a huge correlation to each other. When the body cannot rid cholesterol from the blood stream, it can deposit along artery walls and clog them, making blood flow harder and increases blood pressure. ABCA3 is a member of the ATP binding cassette family of proteins …

An Analysis Of Oas1 Variants Associated In Diabetes Mellitus, Elaine Vanterpool, Ashley Tannis

Student Posters

Type 1 diabetes is caused by a combination of multiple genetic and environmental factors that precipitate autoimmune destruction of the insulin-producing β-cells of the pancreas. Individuals with type 1 diabetes have higher frequencies of OAS1 GG and GA genotypes than nondiabetic's.OAS1, an interferon-induced gene, also known by its official name, 2'-5'-oligoadenylate synthetase 1, encodes proteins that play a crucial role in innate cellular antiviral response which prevents viral replication by activating the adaptive immune system to erase the virus trying to spread. OAS1 is also involved in additional cellular processes such as cell growth and cell death. This gene is …

Understanding How Chaperones Influence Protein Aggregation, Hannah Buchholz

Dissertations (1934 -)

Cells depend on properly folded proteins to function and remain healthy. If proteins adopt a nonnative conformation, they may have an increased propensity to clump together or aggregate, which can compromise cell viability. Unwanted aggregates are linked to a class of diseases called proteinopathies, which include fatal disorders such as Alzheimer’s disease and amyotrophic lateral sclerosis (ALS). Fortunately, cellular factors, known as molecular chaperones, help maintain protein homeostasis by limiting and disassembling protein aggregates. However, the mechanisms that underlie how chaperones modify protein aggregation are poorly understood. The goal of this dissertation is to explore the molecular mechanisms used by …

“Seeing Someone Like Me Succeed Made Me Believe I Could Too!”: Evaluating The Big-Sib & Little-Sib Mentorship Program At Swarthmore College, Lina Verghese , '25

Senior Theses, Projects, and Awards

This thesis evaluates the Bio Big Sib & Little Sib Mentorship Program in Swarthmore College’s Biology Department, a student-led initiative supporting racial/ethnic minority and first-generation, low-income (FLI) students. Launched in 2021, the program pairs upperclassmen with underclassmen to offer guidance, build community, and affirm student identity within a predominantly white, elite academic environment. Using a mixed-methods approach, combining qualitative interviews and survey data, this study examines the program’s effectiveness and long-term impact on student belonging, academic navigation, and identity development. Findings reveal that the program has become a vital support structure, helping participants access the “hidden curriculum” and fostering emotional …

Local Stabilising Density Effects In The Context Of Ecological Disturbance And Community Assembly, Cole J. Doolittle, Joseph A. Lamanna

Biological Sciences Faculty Research and Publications

The maintenance of species diversity in ecological communities has many promising explanations, including certain types of local biotic interactions that generate differential effects on the performance of conspecific and heterospecific individuals. To date, most studies of these local biotic interactions have focused on relatively stable systems, such as mature forests or undisturbed grasslands. However, many ecosystems are far from a stable state, especially under accelerating global climate change. Here, we present a synthesis of local differences between conspecific and heterospecific interactions following disturbances—and how disturbances may alter the strength and scaling of these effects to population growth and species diversity. …

When Can We Detect Lianas From Space? Toward A Mechanistic Understanding Of Liana-Infested Forest Optics, Stefan A. Schnitzer

Biological Sciences Faculty Research and Publications

Lianas, woody vines acting as structural parasites of trees, have profound effects on the composition and structure of tropical forests, impacting tree growth, mortality, and forest succession. Remote sensing could offer a powerful tool for quantifying the scale of liana infestation, provided the availability of robust detection methods. We analyze the consistency and global geographic specificity of spectral signals—reflectance across wavelengths—from liana-infested tree crowns and forest stands, examining the underlying mechanisms of these signals. We compiled a uniquely comprehensive database, including leaf reflectance spectra from 5424 leaves, fine-scale airborne reflectance data from 999 liana-infested canopies, and coarse-scale satellite reflectance data …

From Microplastic Impact To Biodegradation Solutions: Investigating Microplastic Pollution, Microbial Responses, And Efficacy Of Synthetic Microbial Consortia In Plastic Degradation, Rener Sahot De Jesus

Dissertations

Plastics, including microplastics, pose significant environmental threats due to their widespread presence and harmful ecological effects. This dissertation present three distinct, yet interconnected studies. First, a study on microplastic contamination in urban recreational parks was conducted in Al Ain, United Arab Emirates. Results showed that low-density microplastics were present in 87% of soil samples, with spectroscopic analysis identifying synthetic polymers such as polyethylene and polypropylene. Additionally, these microplastics were found to negatively affect soil pH and moisture levels, emphasizing the need for enhanced monitoring and management strategies. Second, the effects of ground microplastics on Photobacterium leiognathi strains, a marine luminous …

Therapeutic Role Of Bioactive Peptides Derived From Hemoglobin, Priya Antony Pereppadan

Dissertations

Bioactive peptides are peptide fragments derived from the proteolytic cleavage or maturation of functional proteins that have shown promising therapeutic potential in addressing major health challenges, including type 2 diabetes, hypertension, and pain management. Diabetes is characterized by high blood glucose levels due to insufficient insulin production or utilization. There are several therapeutic targets for managing diabetes, and one key target is dipeptidyl peptidase IV (DPP IV) due to its role in glucose metabolism. In hypertension, angiotensin-converting enzyme 1 (ACE1) is critical for regulating blood pressure by forming angiotensin II, and its inhibition represents an established treatment strategy. Additionally, the …

Expanding The Lexa Bacterial Two-Hybrid System For Human Protein-Protein Interaction Screening: Application To Tumor Suppressor Par-4, Rebecca M. Richardson

Chemistry & Biochemistry Theses & Dissertations

Protein-protein interactions (PPI) are fundamental to cellular function, influencing processes such as signaling, structural organization, and disease progression. Disruptions in PPIs are implicated in cancer and neurodegenerative diseases, highlighting their importance as therapeutic targets. However, traditional methods for studying human PPIs, such as yeast two-hybrid and co-immunoprecipitation mass spectrometry, are costly and technically demanding. This dissertation explores the LexA-based bacterial two-hybrid (LexA-B2H) system as a cost effective and accessible alternative for investigating human PPIs.

This study focuses on the interaction between glucose-regulated protein 78 (GRP78) and cleaved prostate apoptosis response-4 (cl-Par-4), a tumor suppressor protein involved in apoptosis and neurodegenerative …

Crispr-Induced Mutagenesis Of Arabidopsis Thaliana Gene Apetala3, Hazel Frans, Tara Phelps-Durr

SACAD: Scholarly Activities

This project aims to create CRISPR-CAS9 mutations in the APETELA3 (AP3) gene of the model plant Arabidopsis thaliana. AP3 is a class B gene critical to the petal and stamen development of Arabidopsis flowers. AP3 is defined in a MADS domain, which binds directly to DNA and may be responsible for the expression of the CaRG-box genes. AP3 works in conjunction with PISTILLATA (PI), AGAMOUS (AG), APETALA1 (AP1), and SEPALLATA (SEP) genes to specify the development in the second and third whorls of the flower. While several alleles of AP3 already exist, these alleles are strong alleles that knockout gene …

Optimizing Transcription Efficiency Through Mutations In The T7 Rna Polymerase, Claire N. Novak

Honors Program: Senior Projects (Public)

The production of RNA is vital for many commercial and research purposes, with one of the more notable reasons being vaccine production. The RNA polymerase, derived from T7 bacteriophage, is commonly used for RNA production due to its ability to produce full-length RNA transcripts. However, researchers have faced limitations in optimizing this polymerase. For example, the polymerase generates heterogeneous RNA products that require additional purification steps during RNA production. Here, we selected three amino acid point substitutions based on a recent publication from Moderna that showed increased RNA purity compared to the wild type T7 RNA polymerase sequence. We created …

The Prillwitz Mammoth: Taxonomy, Sex, Age, & Delayed Skeletal Maturation Of A Geologically Young Mammoth, Anna Rybachek

Honors Theses

The Prillwitz mammoth, a nearly complete mammoth skeleton found in Southwest Michigan in 1962, is one of the geologically youngest mammoths from North America (AMS C-14 date: 11,300 ± 100 BP). Bones are well preserved; some long bones show post-mortem flaking, scratches, or grooves of unknown origin. All long-bone epiphyses remain unfused except the distal humerus, suggesting it was < 28 years old at death. In contrast, the skull and mandible preserve M3s and m3s, respectively, that are in mid-wear, indicating an Asian Elephant Year dental age of ~45-50 years. Long bone size and inferred shoulder height are consistent with the size of a large woolly mammoth (Mammuthus primigenius) or small to mid-sized Columbian mammoth (Mammuthus columbi), but dental evidence is most consistent with M. columbi.

Pelvic dimensions suggest it is a male. The ≥ 17-year mismatch between age inferred from tooth progression and wear (~45 Asian Elephant Years) and age inferred from epiphyseal fusion (< ~28 Asian EY if male) may indicate either substantially accelerated dental progression or delayed skeletal maturation for this mammoth; we deem the latter more likely. Based on modern analogs, delayed maturation could have been due to severe malnutrition, hormonal imbalance, illness, or genetic factors. Given the geologically young age of the Prillwitz mammoth (likely near the time of mammoth extinction), we speculate that delayed skeletal maturation may have been attributed to environmental stressors near the end of the Pleistocene. Further work is warranted on very late mammoths.

Critical Thinking Skills: Improvement Through Learning Ownership-Pbl Approach On Students, Ulfa Risqillah, Dwi Listyorini, Sitoresmi Prabaningtyas, Siti Salina Mustakim

Jurnal Pendidikan Sains

Through a method called "Learning Ownership," students actively participate in the educational process and comprehend the context, objectives, and applications of the content they have learned. A learner can customize each educational encounter to align with their present and future learning goals once they have control over their learning processes. The skills and practices required for ownership are highly versatile and applicable in various educational environments. The aim of this study was to unveil the effect of the learning ownership-PBL model on students' critical thinking skills. The sampling technique used in this research was random sampling, which consisted of 2 …

The Effects Of Exposure To Ultraviolet Light On The Activity Of Catalase In Internal And External Tissues Of The Sea Urchin Lytechinus Variegatus, Ellerie C. Heinzmann

Undergraduate Theses

Exposure to ultraviolet radiation (UVR) can have negative impacts on organisms that are exposed to it. The sea urchin Lytechinus variegatus is an organism that resides in shallow waters which can experience exposure to UVR. One negative impact that can occur from UVR is an increase in production of reactive oxygen species (ROS) due to cell stress. In this experiment, two treatments were performed on L. variegatus in the adult state. The first included an exposure to UV-B radiation for 8 hours, and the second was an 8-hour UV-B exposure with temperatures at 30 °C to replicate environmental conditions in …

Refinement Of Megakaryocyte Lineage Commitment In Hematopoietic Stem And Progenitor Cells During Postnatal And Adult Hematopoiesis, Ryan Michael Mack

Dissertations

Mammalian hematopoiesis ensures the continuous production of specialized blood cells, yet the mechanisms that govern megakaryocyte/erythroid (MK/E) bifurcation remain incompletely understood. While HSPCs sustain all blood lineages, how transient waves of progenitors arise and adapt from fetal to adult stages is less clear. This gap in knowledge limits our capacity to precisely manipulate platelet and red blood cell outputs in both developmental and therapeutic contexts. Using refined gating strategies and various bulk- and single-cell transcriptomics, we dissected the traditional “common myeloid progenitor” and Multipotent Progenitor (MPP) compartment into multiple functionally distinct subsets (C1, C2, C3). Within C1, an ESAM⁺ fraction …

Inflammasomes Primarily Restrict Cytosolic Salmonella Replication Within Human Macrophages, Marisa S. Egan, E. A. O'Rourke, S. Kumar Mageswaran, B. Zuo, I. Martynyuk, T. Demissie, E. N. Hunter, A. R. Bass, Y.-W. Chang, I. E. Brodsky, S. Shin

Biology Faculty Works

Salmonella enterica serovar Typhimurium is a facultative intracellular pathogen that utilizes its type III secretion systems (T3SSs) to inject virulence factors into host cells and colonize the host. In turn, a subset of cytosolic immune receptors respond to T3SS ligands by forming multimeric signaling complexes called inflammasomes, which activate caspases that induce interleukin-1 (IL-1) family cytokine release and an inflammatory form of cell death called pyroptosis. Human macrophages mount a multifaceted inflammasome response to Salmonella infection that ultimately restricts intracellular bacterial replication. However, how inflammasomes restrict Salmonella replication remains unknown. We find that caspase-1 is essential for mediating inflammasome responses …

A Study To Identify The Causal Rare Genetic Variants In Primary Open And Closed Angle Glaucoma, Pseudoexfoliation Syndrome, And Associated Glaucoma, Suganya K

Theses and Dissertations

BACKGROUND: Glaucoma is the second most common cause of blindness globally typically diagnosed with a triad of clinical symptoms of increased intraocular pressure (IOP) with associated optic disc, optic nerve head (ONH) changes, and visual field defects. Genetic and environmental factors are some of the strong aetiology factors for glaucoma and identification of these factors has a potential implication in the management of the disease and its outcome. There is a paradigm shift towards understanding the genetics of glaucoma, wherein the variants in the nuclear, mitochondrial genome and other regulatory regions are being identified as contributing risk factors.

METHODOLOGY AND …

College Of Natural Sciences 2024 Year-End Publication, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 2 Dean's Message
Page 3 Department Highlights
Page 4 One Day for State
Page 5 New Students in Wecota
Page 6-8 Faculty Excellence
Page 9 SDSU Physics Students Recognized
Page 9 Prairie Doc Watch Party
Page 10-11 Student Excellence
Page 11 Connections Abroad
Page 12-13 CNS’s Research Centers
Page 14 Connections Abroad
Page 14 Dean Wolf-Hall Retired
Page 15 Outreach Program
Page 15 Events and Traditions
Page 16 Student Spotlight
Page 17 Alumni Spotlight
Page 18-19 SDSU Alum at Paris Paralympics
Page 20 Work Anniversaries & Programs

Induced Mutagenesis In West Nile Virus Non-Structural Protein 3 With A Discussion Of The Mutation's Effects On Viral Properties, Caden Connealy

Honors Program: Senior Projects (Public)

West Nile Virus (WNV), a member of the Flaviviridae family and introduced to the Western hemisphere in 1999, presents a unique and emerging threat to human health. Infection in humans is often mild but can occasionally result in severe neurological impairment and even death. West Nile Virus non-structural protein 3 (NS3) plays an important role in the process of viral genome amplification. More specifically, the C-terminal domain of the protein folds into a helicase enzyme, which is responsible for the “unwinding” of double-stranded RNA intermediates and RNA secondary structure on the WNV genome. This is a vitally important step in …

Barriers And Breakthroughs In The Evolution Of Aggregative Multicellularity, Israt Jahan

Arts & Sciences Graduate Student Theses and Dissertations

The evolution of multicellular organization represents a key innovation in the history of life, yet fundamental questions remain about the evolutionary mechanisms that allowed some lineages to achieve remarkable complexity, while constrained others in their elaboration. The widely accepted single-cell bottleneck model provides a compelling explanation for the success of clonal multicellularity by reducing internal conflict and facilitating developmental integration. However, this perspective does not fully account for the stability and repeated evolution of aggregative multicellularity, where cooperation emerges among previously independent cells that may not be genetic relatives. Aggregative multicellularity demonstrates that the evolution of multicellularity is not a …

Barriers And Breakthroughs In The Evolution Of Aggregative Multicellularity, Israt Jahan

Arts & Sciences Graduate Student Theses and Dissertations

The evolution of multicellular organization represents a key innovation in the history of life, yet fundamental questions remain about the evolutionary mechanisms that allowed some lineages to achieve remarkable complexity, while constrained others in their elaboration. The widely accepted single-cell bottleneck model provides a compelling explanation for the success of clonal multicellularity by reducing internal conflict and facilitating developmental integration. However, this perspective does not fully account for the stability and repeated evolution of aggregative multicellularity, where cooperation emerges among previously independent cells that may not be genetic relatives. Aggregative multicellularity demonstrates that the evolution of multicellularity is not a …

The Anorexigenic Peptide Nesfatin-1 Dampens The B Cell Response To Receptor-Mediated Stimulation Through Inhibition Of Nf-Kb Signaling, Tara L. Steffen, Joshua D. Stafford, Colleen R. Boche, Willis K. Samson, Gina Yosten

Biological Sciences Faculty Research & Creative Works

Nesfatin-1, a posttranslational product of the protein encoded by the nucleobindin 2 gene (NUCB2), was functionally identified as an appetite regulatory molecule in rat hypothalamic nuclei. In the years following the discovery, those findings have been corroborated and expanded upon, and we now know that nesfatin-1 is expressed throughout peripheral tissues and exerts physiological effects beyond feeding control. Literature indicates that adipose tissue is one of the peripheral sources of NUCB2/nesfatin-1, and in this setting, it has anti-inflammatory effects that have recently been implicated in regulating chronic inflammation associated with diet-induced obesity. Currently, there are gaps in our understanding of …

Murine Studies On Ketogenic Modulation Of Metabolism And Epigenetics In Olfaction- Based Learning, Lps Inflammatory Response, And Sex Dimorphisms In Dietary Response, Sara E. H. Moss

USF Tampa Graduate Theses and Dissertations

Ketogenic diets are well-established therapeutic interventions for epilepsy, with documented neuroprotective effects arising from their metabolic, antioxidant and anti-inflammatory properties. Beyond epilepsy, ketogenic therapies are under investigation for various conditions including Alzheimer disease, cancer, diabetes, and cardiovascular disease. These diets suppress insulin levels and shift metabolic physiology toward fat and ketone body metabolism. This elevates circulating levels of ketone bodies, namely beta-hydroxybutyrate, acetoacetate, and acetone, which serve as both energy substrates and signaling molecules. The state of elevated ketone bodies (ketosis) can be achieved with various formulations of a ketogenic diet as well as exogenous ketone supplementation, though the signaling …

Per- And Polyfluoroalkyl Substance (Pfas) Degradation In Water And Soil Using Cold Atmospheric Plasma (Cap): A Review, Victor Somtochukwu Mbanugo, Boluwatife Stephen Ojo, Ta Chun Lin, Yue-Wern Huang, Marek Locmelis, Daoru Han

Biological Sciences Faculty Research & Creative Works

Per- and polyfluoroalkyl substances (PFASs) are persistent organic chemicals found in numerous industrial applications and everyday products. The excessive amounts of PFASs in water and soil, together with their link to severe health issues, have prompted substantial public concerns, making their removal from the environment a necessity. Existing degradation techniques are frequently lacking due to their low efficiency, cost-effectiveness, and potential for secondary contamination. Cold Atmospheric Plasma (CAP) technology has emerged as a promising alternative, utilizing energized reactive species to break down PFASs under ambient conditions. Therefore, this review examines the efficacy and effectiveness of CAP in degrading PFASs by …

Defining B Cell Responses To Emerging Viral Pathogens, Wafaa Al Soussi

Arts & Sciences Graduate Student Theses and Dissertations

The primary series of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines greatly reduced the burden of the coronavirus disease 2019 (COVID-19) pandemic and saved millions of lives. However, waning levels of circulating neutralizing antibodies and the continuous emergence of SARS-CoV-2 variants with increasing numbers of mutations in the spike (S) protein have decreased vaccine effectiveness and led to a recommendation for booster immunizations. In addition, new vaccines based on circulating variants have been developed to enhance the ability of induced antibodies to combat such variants. However, a critical unanswered question was how prior exposure to the ancestral SARS-CoV-2 strain …

Defining B Cell Responses To Emerging Viral Pathogens, Wafaa Al Soussi

Arts & Sciences Graduate Student Theses and Dissertations

The primary series of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines greatly reduced the burden of the coronavirus disease 2019 (COVID-19) pandemic and saved millions of lives. However, waning levels of circulating neutralizing antibodies and the continuous emergence of SARS-CoV-2 variants with increasing numbers of mutations in the spike (S) protein have decreased vaccine effectiveness and led to a recommendation for booster immunizations. In addition, new vaccines based on circulating variants have been developed to enhance the ability of induced antibodies to combat such variants. However, a critical unanswered question was how prior exposure to the ancestral SARS-CoV-2 strain …

The Design, Construction, And Testing Of Mrna Vaccine Against Equine Herpes Virus, Bhawana Devkota

LSU Master's Theses

Equine Herpesvirus-1 (EHV 1) is a worldwide significant pathogen that causes respiratory illness, abortion, and neurological disorders in equine. Current vaccines, including live attenuated, inactivated, and subunit platforms, do not prevent viral latency, mucosal shedding, or cross-strain immunity, requiring alternative approaches. To address these gaps, this project explores the design, synthesis, and in vitro testing of an mRNA vaccine targeting immunogenic EHV 1 glycoprotein (gB, gC, gD, gG, and gM). Epitopes were computationally predicted using the Immune Epitope Database (IEDB), codon-optimized for Bos taurus, and cloned into pUCIDT vectors using SP6/T7 promoters. In vitro transcription (IVT) used nucleotide modifications …

Fossil Leaf Cuticle: Best Practices For Preparation And Paleo-Co2 Analysis, Xiaoqing Zhang, Dana L. Royer, Carina E. Colombi, Juan Martin Drovandi, Jennifer C. Mcelwain, Gaëtan Guignard, Qin Leng, Barry H. Lomax, Nathan D. Sheldon, Rebekah A. Stein, Garland R. Upchurch, Yongdong Wang, Hong Yang, Richard S. Barclay, Ying Cui, Wolfram Kürschner, Joseph N. Milligan, Isabel Montañez, Jon D. Richey, Tammo Reichgelt, Gongle Shi, Selena Y. Smith, Margret Steinthorsdottir

Biological and Biomedical Sciences Department Faculty Journal Articles

Leaf cuticle is the waxy envelope that protects leaves from desiccation, UV damage, and abrasion. The cuticle encodes information about a plant's chemistry and leaf epidermal and stomatal cell morphology. Fossil leaf cuticle has been used to determine taxonomic affinities for almost two centuries and recognized in recent decades for its value in reconstructing paleoenvironments and paleoclimates, especially atmospheric CO2. Fossil leaf cuticle preparation techniques are typically reported as single workflows tied to individual studies, starting with finding fossils in the field through the steps of preparing cuticle for chemical and morphological analysis, including decisions about type of microscopy and …