This Site umd.edu

Training and Research Experiences in Nonlinear Dynamics

Dynamics of Granular Matter and Biophysics

Wolfgang Losert and Derek Richardson

Granular project (Richardson and Losert): The project will involve a combination of experiments and simulations to investigate the collective rotational dynamics of granular systems. Granular systems such as sand have intriguing materials properties - able to sustain forces under some conditions, but able to flow like a fluid when forced in different ways. Recent discoveries that many asteroids are rubble piles raises the intriguing possibility that granular mechanics may also be relevant to asteroid systems. The project will involve a combination of 3D imaging of the rearrangement of granular matter and simulations of 3D granular systems. A focus of the study will be measuring - in both experiment and simulations - the collective rotations of grains that take place when a granular system deforms.

Biophysics project (Losert): The project will be centered on the dynamics of cell migration with a focus on contact guidance of cells by textured surfaces. Migrating cells are guided by a variety of cues including the physical properties of their environment. The project will focus on analysis of how cells - both individual and in groups - are guided in their motion by the texture of their microenvironment. One important question will be to assess the relative importance and competition between guidance cues from other cells and guidance cues from surface texture. Students will learn how to work with cells and carry out quantitative imaging and image analysis. They will work with graduate students and postdocs in comparing their results to models of guided cell migration.

Examples of previous projects include:

  • "Characterizing cell motion on complex surfaces"
    The Losert lab studies how mechanical forces and surface topography contribute to the operation of signaling pathways in cell motility. To assess the role of the physical environment of motile cells, the group nanofabricates controlled cell environments, images and perturbs cell motion on these surfaces, and uses modeling to interpret observed cell dynamics. The undergraduate student project would involve analysis of cell motion using Matlab and contribution to the cell motility experiments (depending on the student's background, more or less experiments would be carried out).
  • "3D imaging of digging in sand"
    The Losert lab is able to image how particles move inside a granular material. Using this novel technique, we will study how clams dig into the sand; for example, as explained in this recent article: http://dsc.discovery.com/news/2008/12/02/roboclam-anchor.html. The undergraduate project would involve carrying out 3D imaging experiments on digging in granular material, extracting 3D particle trajectories using custom Matlab code, and comparing the observations to models of digging.

Professor Losert has mentored numerous undergraduates, including over a dozen students through the TREND program. 

Additional information about Prof. Losert's research can be found at http://ireap.umd.edu/losertlab and by contacting Wolfgang Losert at 301-405-0629 or wlosert@umd.edu.

Additional information about Prof. Richardson's research can be found at https://www.astro.umd.edu/~dcr/ and by contacting Derek Richardson at 301-405-8786 or dcr@astro.umd.edu.