From: Michael P.Jacobsen <jacobsen@biosci.uq.edu.au>
  To  : rasmb@bbri.eri.harvard.edu
  Date: Fri, 23 Jun 1995 12:02:35 +1000

w^2*t

I have a few questions in relation to sedimentation velocity analysis.



1. When is time zero taken in a sedimentation velocity run in the XLA?

2. Does the magnitude of omega and/or time as used by the XLA represent that 
obtained during acceleration and that obtained at constant velocity or just 
that subsequent to a constant velocity being reached?

3. How is the integral omega^2*t derived?

4. Does this derivation take into account events of different speeds used 
within the one sedimentation velocity experiment (viz. leakage tests at a 
lower speed)?

5. What of other analysis packages currently available-do these also rely on 
the integral obtained by the XLA?

6. Does the "time" format stipulated by the user (viz. HOLD, TIME, w2t) bear 
any affect upon what value of the integral of w2t "comes up" above each scan?


Any response appreciated.

Michael P. Jacobsen
Centre for Protein Structure, Function and Engineering
Biochemistry Department
University of Queensland
St. Lucia 4067
Australia.


Phone:      (07) 3653348
Voicemail (07) 3653348
Fax:           (07) 3654699
e-mail:<jacobsen@biosci.uq.oz.au>