In one project, we investigate protein S. Protein S is an important anticoagulant. Its deficiency can lead to potentially life-threatening blood clots. Using a mathematical model of coagulation under flow, we shed new light on the anticoagulant mechanisms of protein S.

We find that during the formation of a blood clot, protein S prevents blood from washing away yet another anticoagulant called TFPI by forming a trimolecular complex on platelets, greatly increasing TFPI concentrations beyond values measured in experiments where blood flow is absent. We also find that deficiencies in the trimolecular complex involving PS and TFPI can counteract severe clotting and bleeding problems related to a modified form of the procoagulant protein called factor V.

Our paper, Mechanisms of thrombin inhibition by protein S and the TFPIα-fVshort-protein S complex, has been published in Biophysical Journal.

In a second project, we investigate platelet-released polyphosphates. Polyphosphates accelerate important reactions that produce blood clots. Extending the previously mentioned mathematical model of coagulation under flow, we identify a mechanism by which polyphosphates can make blood clotting less sensitive to the previously mentioned anticoagulant called TFPI, even when TFPI and polyphosphates do not directly interact.

Our second paper, Modeling the Role of Platelet-Released Polyphosphates in Tissue-Factor-Initiated Coagulation under Flow, is available on bioRxiv.

This research is part of an ongoing collaboration with, Aaron Fogelson (University of Utah), Sradha Ramesh Bhatt (University of Utah), Josefin Ahnstrom (Imperial College London), Jim Crawley (Imperial College London), Karin Leiderman (University of North Carolina at Chapel Hill), Mac Monroe (University of North Carolina at Chapel Hill), Keith Neeves (University of Colorado Denver) and Suzanne Sindi (University of California, Merced), Jim Morrissey (University of Michigan), and Stephanie Smith (University of Michigan). 

In our first project, (see our paper on the left, published in Frontiers in Neuroscience), we define a predictive measure of the propensity to enter REM sleep. We show that the new propensity measure predicts the length and type of the next REM bout in a particular species of nocturnal mice. Our results support the hypothesis that REM need accumulates during non-REM sleep. 

Our paper, A predictive propensity measure to enter REM sleep, is published in Frontiers in Neuroscience, is published in Frontiers in Neuroscience.

In our second project, we apply the new REM propensity measure to understand REM-NREM alternations in both rats and humans.

Our paper, A Data-Driven Measure of REM Sleep Propensity for Human and Rodent Sleep, is available on arXiv, and is under review at Frontiers in Neuroscience.

This research is part of an ongoing collaboration with Cecilia Diniz Behn (Colorado School of Mines), Victoria Booth (University of Michigan), Franz Weber (University of Pennsylvania), Naghmeh Akhavan (University of Michigan), Madelyn Cruz (University of Michigan), Shelby Stowe (Colorado School of Mines), and more, to characterize and predict the drive to enter REM sleep in mammals.

In one project, we develop a new averaging-based model for heterogeneous networks of neurons whose electrophysiological properties vary across the network

We apply the model to the SCN, the brain region that coordinates all of the 24 hr processes (i.e circadian rhythms) across the body

Our paper, A Mean-field Firing-rate Model for the Suprachiasmatic Nucleus, is published in the Society for Industrial and Applied Mathematics' Journal on Applied Dynamical Systems.

Preliminary work on a mechanistic model of how changes in external light, like extra light late in the day due to long-distance air travel, disrupt the coherence of the signal output by the SCN, potentially leading to jet-lag like symptoms, is available in chapter 4 of my doctoral thesis:  Firing-Rate Models in Computational Neuroscience: New Applications and Methodologies. 

Exploratory work in modeling the role of astrocytes in the SCN is also underway.

This research is part of a collaboration with Dr. Jennifer Crodelle (Middlebury College), Dr. Victoria Booth, Dr. Bo Duan (University of Michigan), and Dr. Scott Lempka (University of Michigan), to develop models for the neuronal circuits processing pain signaling in the dorsal horn of the spinal cord.  We're particularly interested in mechanisms that lead to dysregulation of signal processing, resulting in chronic pain.

Our paper is published in PLoS Computational Biology, and is available on the left.

We investigate public goods games in which some players contribute to a common resource, the resource grows, and then players share equally from the common pool.

We showed that the presence of stochastic non-participation facilitates cooperation in the public goods game.  

This research was for an REU I did with Feng Fu at Dartmouth College in Summer 2017, and was published in 2018 in the journal, Games.

This was a class project I completed with Caleb Mayer at the University of Michigan in Fall 2021