Research

National Institute of Allergies and Infectious Diseases (NIAID) from https://www.verywellhealth.com/hiv-microscopy-in-pictures-48651

Project Description:  Coupling the dynamics of a human immune system in the presence of an HIV virion with a population level epidemiological model of disease spread presents several challenges. In this project, we are developing a combined model where the infectiousness of the individual is a function of the viral load of the individual.
Faculty: Hoffman, Katharine Gurski (Howard U)

Student(s): Maliha Noushin

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Project Description:  HIV treatments come with many side effects, which leads to compliance issues. If instead of taking a constant dose of medication, there was an on-again, off-again strategy for dosing of medication that depended on the viral load of the individual. This would reduce the toxicity of the treatment for the individual. Using methods of parameter estimation, sensitivity, and identifiability, we develop a model of STI for HIV treatment.
Faculty: Hoffman, A. Biswas, K. Gurski, and.

Student(s): Matt Lastner

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Project Description:  Using a novel dataset from Dira Dawa Ethiopia, we develop a model of the spread of malaria that includes susceptible and infected humans, as well as infected mosquitos. Using data assimilation methods, seasonality in the disease spread is predicted without an underlying modeling assumptions. Parameter estimates from the estimation show larger estimates for transmission rates than those from the literature.
Faculty:  A. Biswas, K. Gurski and.

Student(s): Mac Luu

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Project Description: Dengue fever is a vector-born disease carried by mosquitos. UMBC undergraduate students N. Seymour and O. McMann studied a model of dengue fever with susceptible and infected humans, and infected mosquitoes. The model admits both a disease-free (DFE) and endemic (EE) equilibrium, and subsequence linear stability analysis confirms the standard result that the DFE is stable for R0 <1 and loses stability for R0>1. Global stability is addressed using a Lyapunov function. Parameter identifiability, sensitivity, and estimation are performed using a published data set from Singapore.
Faculty: Hoffman

Student(s): N. Seymour and O. McMann

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Project Description:  Cholera is a disease from water-born bacteria and is correlated with large rainfall events such as hurricanes in countries that face challenges with respect to sanitation. Data assimilation is combined with parameter identifiability, sensitivity, and estimation to study a model of cholera.
Faculty: Hoffman

Student(s):  Rileigh Mansfield

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Project Description:  Using data to inform models of nucleus accumbens neurons in mice Tara LeGatesin the Department of Biological Sciences and Kathleen Hoffman in the Department of Mathematics and Statistics has been investigating parameter identifiability and estimation for the Izhikevich model of neurons in the nucleus accumbens, a key area of the brain that mediates motivated behaviors and is implicated in stress-based psychiatric disorders like depression. We record firing properties from individual neurons in the mouse brain using whole-cell patch clamp data, which we use to inform our model and estimate parameters. Preliminary results have shown that the value of some of the parameters depend on the sex of the mouse as well as exposure to environmental stress. This work began as part of Ashley Copenhaver’s Ph.D. dissertation and has continued with the efforts of undergraduate research students Owen Tolbert and Branwen She, as well as Master’s student Matyas Marek.

Faculty:  Hoffman, and Tara LeGates (Bio)

Student(s):  Ashley Copenhaver and Matyas Marek

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Project Description:  Can an individual beta cell control the synchronization of an entire islet?  What conditions may be necessary or sufficient for the network structure and nonlinear cellular dynamics to support such a cell, a switch cell?  We consider reduced model cells and networks to address these questions.
Faculty: Peercy

Student(s): Zainab Almutawa

References:

1. β Bradford E. Peercy and David J Hodson, Synchronizing beta cells in the pancreas ELife 13, e95103 (2024)
2. β Bradford E. Peercy and Arthur S. Sherman, Do Oscillations in Pancreatic Islets Require Pacemaker Cells? Journal of Biosciences, Feb 25; 47:14 (2022)
3. β Janita Patwardhan Hogan^G and Bradford E. Peercy, Flipping the Switch: Islet Desynchronization through Cell Silencing. PLoS ONE, Apr 2 (2021)

Project Description:   We are investigating the mechanisms for active sensing using the electric fish as a model organism. The collaboration that includes biologists, mathematicians and engineers has identified a common velocity distribution across taxa, species, and sensing modalities. Continuing analyses of experimental data has shown that for a stationary shuttle that the fish has preferred positions within the shuttle related to shuttle windows.

Faculty:  Hoffman, Noah Cowan (JHU), Andrew Lamperski (UMN), and Eric Fortune (NJIT)

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Project Description:  In development cell migration is a critical component.  We study the fruit fly egg chamber development.  Mathematical models can help generate testable hypotheses for quantities that are challenging to capture experimentally.  We combine genetic mutation with reaction diffusion equations and/or agent based models to capture chemoattractant distribution and clustered cell migration.
Faculty: Peercy (Math) and Starz-Gaiano (Bio)

Student(s): Lara Scott

References:

1. A. George, N. Akhavan, BE Peercy, M. Starz-Gaiano,Alexander, Chemotaxis of Drosophila border cells is modulated by tissue geometry through dispersion of chemoattractants, iScience, Volume 28, Issue 3, 111959.
2. ⊙ Bradford E. Peercy, Michelle Starz-Gaiano, Clustered cell migration: Modeling the model system of Drosophila border cells. Seminars in Cell & Developmental Biology, (2020). [Pubmed]

Project Description: Experiments performed in the Padmanahban laboratory show sustained tumor growth in mouse ovaries.  We use an advection equation for probability density of matestatic tumor cell size to compare with Wild Type and mutant data.
Faculty: Peercy (Math) and Padmanahban (Bio)

Student(s): Jessica Hoffman

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Project Description: The neuromuscular junction in Drosophila is a model system for proper synaptic distributions.  To compare with data in the Vonhoff laboratory, we use models of oscillatory cAMP and Calcium to capture proper pruning or pathological ecotopic, en passent synaptic connections.
Faculty: Peercy (Math) and Vonhoff (Bio)

Student(s): Alice Yacubovich

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Project Description: The processes controlling the feedback between cellular behaviors and mechanochemical signals to achieve precise and stable tissue morphologies are poorly understood. This project will develop new agent-based methods based on high-performance computing to enable the simulation of whole-body organisms composed of millions of cells that grow, divide, and die based on diffusible morphogens. These methods will pave the way for elucidating the mechanisms of the regulatory dynamics of development and regeneration and pave the way for novel biomedical and bioengineering applications.

Faculty: Daniel Lobo
Student(s): Emma Chaney
References:
B. Kaity, D. Lobo. 2025. Emergent stable tissue shapes from the regulatory feedback between morphogens and cell growth. bioRxiv, doi: 10.1101/2025.02.16.638504.
J.M. Ko, W. Reginato, A. Wolff, D. Lobo. 2024. Mechanistic regulation of planarian shape during growth and degrowth. Development, 151 (9): dev202353.
R. Mousavi, D. Lobo. 2024. Automatic design of gene regulatory mechanisms for spatial pattern formation. NPJ Systems Biology and Applications, 10(35).