Math Bio Seminar 2026 Spring Schedule
We meet on Wednesdays from 3:00 to 3:50 PM (EST) in Ayres G004.
Feb 18
Speaker: Belinda Akpa (University of Tennessee, Knoxville)
Title: Systems modeling integrates scarce, discordant observations to uncover quantitative answers in the qualitative data describing plant Fe homeostasis
Abstract: Iron (Fe) plays a catalytic role in all primary metabolic processes. But Fe is a potent redox agent that can generate reactive oxygen species, promoting the destruction of structural and functional biomolecules. Hence, Fe uptake, bioavailability, and localization must be tightly controlled in response to changing developmental and physiological needs. In the model plant Arabidopsis thaliana, BRUTUS (BTS), is an iron-binding ubiquitin ligase protein thought to choreograph Fe deficiency responses across the plant while being confined to the plant vasculature. The protein’s abundance and activity respond to physiological Fe, but the molecular evidence about its function seems to contradict the organismal evidence about its role in Fe regulation. Phenotypic observations suggest that BTS acts as a brake on mechanisms that drive Fe uptake: when BTS is knocked down, the plant accumulates more iron. However, molecular data indicate that BTS is normally upregulated in the setting of Fe deficiency.
In vitro studies have reported BTS destabilization as Fe levels increase. By contrast, live-cell imaging reveals increased cytosolic BTS as Fe levels increase. Furthermore, mutations that partially abrogate Fe binding produce divergent levels of cytosolic and nuclear BTS. Using mathematical modeling as a formal, testable sense-making strategy – at the core of an iterative modeling-experimentation loop – we identified a kinetic regime under which Fe-responsive stability and translocation of BTS could concurrently explain this group of empirical observations. Supported by further validation of our model’s predictions, we posit that BTS abundance is a non-monotonic function of Fe status, defined by competing effects of Fe-mediated stability, proteasomal degradation, and Fe-stimulated nuclear translocation.
Feb 25
Speaker: Jessica Kingsley (University of Tennessee, Knoxville)
Title: Models of the Spread of Crimean Congo Hemorrhagic Fever and the Treatment of Metastatic Cancer via Neoantigen Vaccine
Abstract: In this talk I will present two distinct projects: The first is an ODE-based model of Crimean Congo Hemorrhagic Fever (CCHF), a tick-borne illness that affects animals and humans across the globe. Our model captures transmission among three life stages of ticks, humans, cattle, and small mammals, as well as co-feeding transmission dynamics. We adapt this model to Uganda’s Cattle Corridor, a region in Uganda categorized by cattle farming with high prevalence of CCHF. This project was partially supported by the MASAMU program with funding from a National Science Foundation (NSF) grant based at Auburn University. The second project is a coupled ODE-PDE model of metastatic cancer treatment with neoantigen cancer vaccine. We use a system of ordinary differential equations to model the treatment of a primary tumor, and couple the system with a partial differential equation that tracks the number of metastases per time and size. Vaccine dosage is taken as a control in the ODE system to decrease the primary tumor burden and in turn, slow the spread of metastases. An optimal control problem is formulated to design vaccine treatment.
Numerical simulations of both models will be presented as well.
March 4
Speaker: Ryan Campbell (University of Tennessee, Knoxville)
Title: Extending Intermittent Search Strategy and a Stochastic Network Analysis of an Opioid Use Disorder Model
Abstract: The ability to successfully forage for food or prey is essential to many species. While Lévy flights have drawn interest in the past for modeling this process, intermittent search strategies may provide a better explanation. This process can be described by a system of differential equations that include both a detection, diffusive phase and an advection, ballistic phase. By analyzing these equations, we can determine the average time it takes for the searcher to find its target throughout a variety of scenarios, and often, we can also determine the optimal switching rate between each phase. In the first part of this talk, we will present results for two biologically relevant extensions on the original intermittent search strategy formulations geared towards searches in fluid-dominated environments.
Opioid-related mortality has steadily been increasing for the past three decades, with the U.S. Department of Health and Human Sciences maintaining a nationwide public health emergency since 2017. In the hopes of formulating intervention strategies, many mathematicians have modeled this epidemic, including Kimberlyn Eversman who developed a community/population compartmental model to understand how a specific subcommunity could be affected by the crisis. In the second part of this talk, we will present a stochastic model that uses Eversman’s model to understand how population dynamics can affect an individual within the network.
March 18
Speaker: Bhargav Ram Karamched (Florida State University)
Title: Foraging for Food and Competing with Neighbors: A Model’s Perspective of the World of Ants
Abstract: Collective behavior and self-organization are fascinating phenomena observed in a number of species. A fascinating example is that of ant foraging and trail formation, which emerges from indirect, chemical sensing that drives ant behavior. While basic tenets of ant foraging have been identified, several factors still remain unexplained. Most models show how a colony of ants forms a single trail to a single localized food source. However, ants develop simultaneous trails to multiple food sources. In this talk, I will discuss two features of trail formation. First, we develop a stochastic lattice model that describes the emergence of multiple trails to multiple food sources. We derive a macroscopic PDE that is amenable to analysis and coincides with the results of the stochastic model. Linear stability analysis demonstrates the stability of trail formation absorbing outcomes. In the second part of the talk, I will discuss how trail formation is affected by competing species from the perspective of a symmetry-breaking mechanism. We show that winning a competition is divided into two subphases: (1) a colony must find the food first and (2) a colony must repel away (intimidate) other colony ants to hold on to the food. We derive a scaling law that describes the conditions for victory in a competition.
March 25
Speaker: David Garber (University of Tennessee, Knoxville)
Title: TBD
Abstract: TBD
April 1
Speaker: Maruf Lawal (University of Tennessee, Knoxville)
Title: TBD
Abstract: TBD
April 15
Speaker: Jackson Page-Roth (University of Tennessee, Knoxville)
Title: TBD
Abstract: TBD
April 29
Speaker: Necibe Tuncer (Florida Atlantic University)
Title: TBD
Abstract: TBD