sedimentation at 1g...

Ed Rybicki ED at MOLBIOL.UCT.AC.ZA
Mon Apr 1 02:32:35 EST 1996


> From:          robert.coelen at jcu.edu.au (Robert Coelen)
> Subject:       Re: sedimentation at 1g...
...
> > preparations left the same length of time (spherical, 30 nm, +/-100S) 
> > are uniformly suspended still - but rod-shaped chaps of 150-300 nm 
> > and +/-200S sediment beautifully.
...
> Simple logic said that it should be so, but did in the 26 years or so
> any earth tremors occur ?  Pulling out my calculator and assuming
> 30 minutes at 100,000g 's would be enough to pellet the virus I
> calculate that at 1 g    this feat could be repeated    in somewhat
> less than 6 years ! Would anyone care to set up an experiment ?

Well, we have two offers...one involves either decreasing the mass of 
the Earth by half, or a microgravity run in the shuttle for 26 yr, 
and the other involves monopolising a centrifuge at 2g for its 
entire working life...and yes, there were not only tremors but movement 
of the bottle, so it was probably undisturbed for only 16 yr.

> Nice going Ed ! Can we expect a write up ?

Weeeellll....no, in that people want REPLICATES, and I rescued a 
couple bottles as they were about to be poured down the drain (pour 
GRAMS of TMV / BSMV / BMV down the drain??  I didn't say that...), 
and most got shook up to see that they were not in fact fungus, 
leaving one bottle of BSMV for demo purposes to students, essentially 
undisturbed since 1984.  So call again in 12 yrs.

                     Ed Rybicki, PhD  
      Dept Microbiology     |  ed at molbiol.uct.ac.za   
   University of Cape Town  | phone: x27-21-650-3265
   Private Bag, Rondebosch  |  fax: x27-21-650 4023
      7700, South Africa    |   
    WWW URL: http://www.uct.ac.za/microbiology/ed.html      
                                        
"And then one day you find, ten years have got behind you"



More information about the Virology mailing list