From: Dr A.J. Rowe <ajr@leicester.ac.uk>
  To  : RASMB@bbri.eri.harvard.edu
  Date: Wed, 26 Jul 1995 11:05:41 +0100 (BST)

Cell, fringes & all that

With regard to the points being made about cell baselines etc in interference
fringe optics, the new XLA, etc.  
I recall that back in the middle ages I published a modified fringe relaxation
procedure which provided an approach to both the estimation of the 'baseline'
and the estimation of the true total fringe number in LSE work (J Mol Biol, 97,
202-205, 1975). This followed on from earlier work by Charlwood and by LeBar.
Now of course there is always the 'hysteresis' problem to cope with in
multi-speed runs, but looking back at the data I notice the fact (not commented
on in the text) that changes on acceleration were transient (Figure A1 of the
ref cit. - early few minutes of the data). 
I suspect that this approach is probably as valid as a 'dummy run' methodology
- the latter is surely not free of hysteresis problems, in any case.

Any comments out there ?

Arthur Rowe

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Dr Arthur Rowe
Director
UK National Centre for Macromolecular Hydrodynamics
Leicester Laboratory
Adrian Building
University of Leicester
Leicester LE1 7RH    UK
Tel: +44 (0)116 252 3448
Fax: +44 (0)116 252 5260
ajr@le.ac.uk
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