One of the central mysteries of living systems is how they can perform complex functions on large scales despite being intrinsically disordered on microscopic scales. This interplay is a two-way street: individual cells develop and maintain the form of the collective, and collective properties in turn feed back onto the behavior of individual cells. To better understand how mechanical information can flow between local and global scales in this manner, I work closely with experimentalists and theorists to develop simple models of complex biological architectures.

Mechanosensing in disordered fiber networks

    Certain types of eukaryotic cells, including human cells, can actively probe and respond to the stiffness of their surroundings. What can a cell learn about its tissue scaffolding by pulling on nearby fibers?

    I modeled the tissue matrix as an elastic network that deforms in response to external forces. This mechanical model helped identify "intelligent" strategies that cells can use to discern tissue identity.

Architectural transitions in bacterial biofilms

    Biofilms are groups of bacteria that adhere to and grow on surfaces. Recent advances in imaging technology showed that within a colony, cells are not arranged randomly, but instead grow into spatially-patterned formations with striking geometrical order. How do simple bacteria self-organize into these complex structures?

    To understand how cell-scale interactions determine the form of the collective, I modeled bacteria as growing, sticky rods. I explored this model by developing an agent-based C++ simulation framework that I have made freely available at GitHub. My investigations helped me create theories that yielded quantitative insights into the structure, shape, and dimensionality of Vibrio cholerae biofilms.

Article in Nature Physics:

Physical limits to sensing material properties

    A fundamental way of learning about a material is by observing how it responds to stimuli. However, all materials respond heterogeneously at small scales, which limits what such probes can learn. How much information can be gleaned by probing a material?

    I discovered a bound on this information by studying a simple model of a sensor that probes a material in the continuum limit. My work reveals how one can construct devices capable of sensing near these bounds, e.g. for medical diagnostics.

Open access article in Nature Communications:

Genome maintenance during aging

    Repeated sequences in the genome play essential roles in the lives of cells, such as enabling the highly parallel production of ribosomes. These sequences are prone to being lost to recombination that occurs when the genome loops onto itself. How are repeated sequences maintained over many generations?

    To elucidate how repeated sequences are maintained in the genome, I am investigating stochastic models of the copy number that incorporate the effects of recombination and redistribution during replication. Using these models, I have identified several mechanisms that cells may exploit to reliably preserve their genomes.