Re: [ccp4bb] Second moments of Z but not twinning

- Protein crystallography

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- Protein purification
- Crystallisation

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

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Subject: New version of clipper (includes buccaneer, pirate, ...) available from CCP4 download pages
From: "Remacle, F (Francois)" f {- dot -} remacle {- at -} DL {- dot -} AC {- dot -} UK
Date: 2007-06-01

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Subject: Re: Second moments of Z but not twinning
From: David Briggs bassophile {- at -} GMAIL {- dot -} COM
Date: 2007-06-01

Subject: Re: Second moments of Z but not twinning
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2007-06-01

Have you looked at http://www.ccp4.ac.uk/dist/html/pxmaths/index.html

It is an introduction ..
Eleanor

Randy talked about deviations at the CCP4 study weekend this year..

Winter, G (Graeme) wrote:
>
> Hi Folks,
>
> I was wondering if there is a document somewhere explaining some of
> the more interesting things which can be interpreted from the plot of
> second moment of Z = I'/ anywhere? I've looked around and I can't
> find much beyond the things pertaining to twinning, where it will have
> the magical values of 2.0 or 1.5. What about if it is say 2.0 around
> the low resolution regions but gets much bigger?
>
> Looking at the truncate source code there is a note to the effect that
> the second moments may be greater than two in when you have
> pseudotranslational symmetry. In this case, however, I would expect
> that the effect would be uniform across the resolution ranges… any
> thoughts?
>
> Any pointers would be greatly appreciated.
>
> Thanks,
>
> Graeme
>

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Next message:
Subject: Re: Second moments of Z but not twinning
From: David Briggs bassophile {- at -} GMAIL {- dot -} COM
Date: 2007-06-01