Christel Hohenegger CIMS, NYU Wednesday Jan. 15, 2010 3:05pm in LCB 215 Modeling Biological Fluids Abstract: Cystic fibrosis is a common but lethal hereditary disease. One of its symptoms is the dehydration and increased stickiness of lung mucus, which results in frequent lung infections. Recent experimental approaches, termed microrheology, have attempted to extract the pertinent mechanical properties  viscous and elastic material response  from very small volumes of material by measuring statistical quantities such as auto and crosscorrelations of optically tracked beads. However, microrheology still lacks good understanding, and consequent technical tools, from basic physical modeling. Using the physical picture of twopoint microrheology, I have developed and analyzed a Langevinbased model of the fluctuations of two beads in a viscoelastic fluid, allowing a direct mapping of statistical observables to mechanical properties. One application of this model is the study of mean passage time of a tracer through a mucosal layer which is relevant to the design of drug treatments.
I will also briefly introduce the topics of active suspensions. The
dynamics of such suspensions  bacterial baths are an important
example  has been the focus of much experimental and simulational
work in recent years. Here I will describe and discuss a recent
kinetic PDE model which has been the basis for my theoretical work
on stability  given in detail in my colloquium talk  focusing on
its underlying assumptions, structure, and some of its deficiencies.
