SearcharxivSearch

arXiv subjects

Steve Plimpton

Publications and source records attributed to Steve Plimpton.

2 recordsLinked to original sources

Sensitivity analysis of a computational model of the IKK-NF-κB-IκBα-A20 signal transduction network

The NF-κB signaling network plays an important role in many different compartments of the immune system during immune activation. Using a computational model of the NF-κB signaling network involving two negative regulators, IκBα and A20, we performed sensitivity analyses with three different sampling methods and present a ranking of the kinetic rate variables by the strength of their influence on the NF-κB signaling response. We also present a classification of temporal response profiles of nuclear NF-κB concentration into six clusters, which can be regrouped to three biologically relevant clusters. Lastly, based upon the ranking, we constructed a reduced network of the IKK-NF-κB-IκBα-A20 signal transduction.

q-bio.QM

Counterion Condensation in Strong, Flexible Polyelectrolytes

We present results of molecular dynamics simulations of strong, flexible polyelectrolyte chains in solution with added salt. The effect of added salt on the polyelectrolyte chain structure is fully treated for the first time as a function of polymer density. Systems above and below the Manning condensation limit are studied. The chain contraction due to added salt is weaker than expected from simple screening arguments. The chain structure is intimately tied to the ion density near the chain even for chains in the counterion condensation regime. In contradiction to Manning counterion condensation theory, the ion density near the polymer chain depends on the amount of added salt, and above the condensation limit the chains significantly contract due to added salt.

cond-mat.soft