Calcium modeling: My postdoctoral position (under the direction of Dr. Gregory Conradi Smith) focused on the computational and mathematical modeling of the dynamics of calcium-gated calcium channels. Calcium is an important second messanger that is present in many systems, including cardiac muscle cells, neurons and oocytes. My postdoctoral work investigaged the dynamics of calcium accumulating near the calcium-gated channels and its feedback on the channel open probability. My work explored this question both in a spatially homogeneous and a spatially heterogeneous domain. I continued this work in my tenure-track position at Humboldt State University. With funding from a California State University-wide organization (CSUPERB), I supported two undergraduate research students to examine how entire release sites made up of a collection of calcium-regulated ion channels behavesand how the calcium accumulating near the release site changes the collective dynamics. We published our findings.
Mechanical signal transduction in endothelial cells: I first started a project on endothelial cell mechanotransduction with Dr. Abul Barakat while I was a graduate student at UC Davis. Endothelial cells (EC) form a protective layer in blood vessels. It has been clearly established that ECs respond in a genetic, physiological and morphological way to distinct flow regimes. Whether the EC response is pathological or protective is an important first step in the development of various cardiovascular diseases from atherosclerosis to high blood pressure. Because early EC responses to changes in blood flow are fast (on the order of milliseconds) and because the signal is a physical (changes in shear, pressure and tension), it is thought to be very important to consider how mechanical signals are transmitted in endothelial cells. I had worked on three related projects in this area that all took a similar modeling approach: the EC is represented as a network of connected viscoelastic elements with distinct material properties.
Neuroanatomy of zebrafish sensorimotor pathway: Applying graph theoretical approaches to neuroanatomy is a relatively new field that has been aided by various technological advances in neuroscience that allow the visualization of large portions of the nervous systems of various organisms. Graph theoretical approaches have been used to identify features that all neural networks share but there are still many gaps in our knowledge and disagreements about the extent to which various neural networks share an organizational structure. My collaboration on the zebrafish sensorimotor pathway with Gahtan lab fits into this larger context of inquiry.
In my work with graduate students in the (now suspended) Mathematical Modeling Option of the Environmental System Gratudate program involved many different systems and approaches. Several of the projects with individual-based models or IBMs. This is a relatively new modeling framework that has a lot of local expertise through the work of Dr. Steven Railsback. In usual population models, an average behavior is assumed for all individuals in a population and this average behavior is modeled. In the IBM framework, it is assumed that individuals in a population have unique characteristics and their behavior is limited by these characteristics. For example, when foraging, an individual’s behavior may depend on its relative dominance, level of hunger, ability to move certain distances, etc. The IBM framework has been used in many projects in conservation biology in an attempt to link individual behavior to patterns that emerge on a population level.
To find out more about my work, you can find me on ResearchGate.
Larripa, K, Mazzag, B: “A modular approach to teaching mathematical modeling in biotechnology in the undergraduate curriculum”, PRIMUS, 26(5), 485-504, 2016.
Mazzag, B., Gouget, C.L.M., Hwang,Y., Barakat, A.I., “Mechanical Force Transmission via the Cytoskeleton in Vascular Endothelial Cells”, “Endothelial Cytoskeleton”, Rosado, J.A., Redondo, P.C., (editors), CRC Press/Taylor and Francis Group, 2013. (invited chapter)
Stobb, M., Peterson, J.M., Mazzag B., Gahtan E., “Graph theoretical model of a sensorimotor connectome in zebrafish”, (2012). PLoS ONE,7(5): e37292. doi:10.1371/journal.pone.0037292
Mazzag, B., Barakat, A.I., “The effect of noisy flow on endothelial cell mechanotransduction: a computational study”, (2011). Annals of Biomedical Engineering, 39(2):911-21.
Mazzag, B., Tignanelli, C.,Smith, G.D. "The effect of residual Ca2+ on the stochastic gating on Ca2+-regulated Ca2+ channel models", (2005).Journal of Theoretical Biology, 235:121-150.
NSF INCLUDES WATCH US Mini-grant. Leveraging the Mathematical Contest in Modeling to Support Undergraduate Women in Mathematics. B. Mazzag, Larripa, KR. $3900. 2018.
PIC Math. Mini grant to develop and teach “Preparation for Industrial Careers in Mathematics” course at HSU. 3 WTU release time and travel to PIC Math workshop, Provo, UT. $5,000. May 2016 – May 2017.
Co‐PI with PI Tyler Evans on a grant entitled “Hybrid Math courses for Core Math Courses” Sub-award in the amount of $18,327 to redesign Math 115, Precalculus. The award from the Gates Foundation was to CSU Northridge. The grant was effective January 1, 2013-December 31, 2013.
CSUPERB Programmatic Grant:A curriculum development grant with co-PI Kamila Larripa in the amount of $11,115 for developing a course “Introductory Mathematical Biology for Biotechnology”. Funded by the CSUPERB. The grant was effective May 2010-October 2011.
Mazzag, B. “A mathematical modeling framework for endothelial mechanotransduction”, Cellular and Cardiovascular Engineering Lab, Ecole Polytechnique, February 2015, Department of Applied Mechanics, Budapest University of Technology and Economics, February 2015.
Peterson M.J., Stobb M., Mazzag B., Gahtan E. “Computational Graph Theoretical Model of the Zebrafish Sensorimotor Pathway.” Applied Mathematics, Modeling and Computational Science Conference, Waterloo, Canada, July 2012.
Pace, J., Mazzag, B., Barakat, A.I. “Going with the flow: How Endothelial Cells Distinguish Between Steady and Oscillatory Flow Using Ion Channels.” Society for Mathematical Biology Annual Meeting, Rio de Janeiro, Brazil, July 2010. Session organizer. Session title: Endothelial cell mechanotransduction.
Mazzag, B., Tignanelli, C., Smith, G.D. “Analysis of the effect of residual calcium on the gating of calcium-regulated calcium channels” Society of Industrial and Applied Mathematics Life Sciences Joint Meeting with the Society for Mathematical Biology, 2005. Session organizer. Session title: Intracellular Calcium Modeling: Spatial Considerations on Multiple Scales.
Ari Kornfeld, 2006: Measuring and modeling the gravitropic response of oat shoots (Avena sativa)
Jon Pace, 2011: Endothelial cells and blood flow: a mathematical model of early mechanical and electrophysiological reponses to shear stress
Alan Evangelista, 2015: Modeling the effects of sea level rise on Long-billed Curlews at Humboldt Bay
Aaron Greenberg, 2010: A model of the longterm persistence of the valley elderberry longhorn beetle
Josh Peterson, 2014: Individual-based modeling of colony growth in an encrusting bryozoan, Watersipora subtorquata
Tyler Belarde, 2012: Evaluating cumulative effects of within-day flow fluctuations and presence of non-native species on age-0 Colorado pikeminnow (ptychocheilus lucius) in nursery habitats of the Green River (Utah)
Michael Stobb, 2012: A dynamic neural network model of the zebrafish posterior lateral line sensorimotor pathway