Experimental Biological Physics:
Study the role of sensory cilia in cellular mechanosensation and optical probes of matter. Experimental tools used include epithelial cell culture and electrophysiology, microscopy and laser tweezers, microfluidics and analytical modeling of fluid flow in porous tubes. Biological systems under investigation include renal and airway epithelial tissue, and physical systems studied include colloids and gels. - Macromolecular crystallography study of proteins involved in pyrimidine biosynthesis using x-ray crystallography.
Fluid Dynamics and Mixing:
Understanding the fluid flow and its interaction with geometrical structures is critical in the design and performance optimization of chemical and biological synthesis and analysis systems. Computational modeling and experimental investigations are employed to a broad range of applied problems that require the manipulation of fluids, ranging from the optimization of mixing in microfluidic devices, to the fluid flow mapping in polymer extruders, and the development of efficient microreactors.
Explore biological systems through theoretical and computational methods for biosensing, synthetic biology, biophysics, and materials sciences applications. Tools used include molecular dynamics, coarse-grained modeling, analytical modeling, stochastic methods and agent-based simulations. Biological systems under investigation include DNA molecules and proteins, DNA origamis, bimolecular complexes, microtubules, and C. elegans colonies.
Laser spectroscopy is being used to study diffusional processes that result in the formation of fractal aggregates and phase transactions in liquid mixtures, complex fluids, and microemulsions are under investigation. The optical properties of various polymer solutions, micelles, and microgels also are being studied using laser techniques.
Methods from statistical physics, such as the renormalization group technique, and computational tools are used to study liquids, polymers, superconductors, magnets and biopolymers (proteins). Statistical Physics methods and stochastic processes are applied to cognitive science, polymer processing and problems from biology.
High-Resolution Imaging of Soft Matter Systems:
While electron microscopies have emerged as one of the most versatile tools in instances where extreme spatial resolution is required, their application is limited when the materials of interest are sensitive to electron beam damage. In these cases, in order to be imaged the samples have to undergo severe alterations including cryogenic or chemical fixation, to enable them to withstand the harsh conditions to which they are exposed while being imaged in electron microscopes. This work is focused on developing alternative strategies enabling high-resolution electron imaging of beam-sensitive soft matter materials without alteration.
Looking for curious events and effects of physics in the everyday world Flying Circus of Physics, 2nd Edition.
Scanning probe microscopy is being used to examine nanoscale physics at surfaces. Surfaces are interesting because surface atoms do not have as many bonds as atoms in the bulk of a crystal, which can affect their properties, including magnetism and electronic conductivity. Further, the arrangement of atoms on a surface has profound implications for devices because how new atoms arrange on a surface can affect how abrupt an interface between two materials is or how ordered the next layer of atoms are. Of particular interest is: (i) How we can use surface structures to control self-assemble of nanostructures and molecules; and (ii) How do molecules diffuse and move across a surface? This experimental work is paired with computer simulations to better understand the physics of these surfaces.
The Earth's atmosphere exhibits many different aspects of physics, ranging from radiative transfer to fluid dynamics and thermodynamics. Our group uses high-resolution computer simulations (LES), as well as observational data, to study atmospheric flow, in particular the turbulent structure of the atmospheric boundary layer and boundary layer clouds.
Mie scattering calculations are presently being undertaken on artificially produced and natural aerosols for the purpose of understanding a number of atmospheric and basic scattering phenomena. The structure of optical caustics produced by liquid droplet lenses also is being investigated both experimentally and theoretically. Light scattering methods are being applied to the operation of laser tweezers.
Dr. James Lock