[RASMB] Sed Velocity in 8M Urea

[Morgan, Charles]

Very new to the field and still learning!!

I set up a sedimentation velocity in 8M urea forgetting that the protein
would move very slowly through the cell!
I did not set enough time and the meniscus is only depleted in the first
0.15cm of the cell (6.3 to 6.4cm).  For my control sample (no urea), the
last scan has zero signal for most of the cell.  No problems with this data
set.

What is the best way to analyze the data (total 90scans per cell, 5.5hr at
40000)?  I am expecting some sample heterogeneity and currently use
continuous c(s) distribution in SedFit 8.3.  I adjusted the viscosity to
1.122 but the fit seems to be in a local minimum.   What should I choose for
parameters especially frictional ratio?  Or is the data set just too
limited?

Any advice and information gratefully received.

Thanks,  Charles.