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Dear all,<BR>
phenix.xtriage estimates a twin fraction<BR>
of between 24 and 30% but then when I start the refinement<BR>
I get 47-49%. In CNS if I fix the twin fraction in a series<BR>
of refinements the Rfactors jump from 44% (twin fraction 0)<BR>
to 37% (from 25% to 49%, only marginal improvement<BR>
upon going from alpha=25% to 49%). Questions:<BR>
<BR>
1. Is the refinement of alpha dependent on the model?<BR>
2. I am tempted to work with the 30% that xtriage estimates<BR>
but do not know how: is there a way to fix alpha?<BR>
<BR>
Thanks<BR>
<BR>
Pietro<BR>
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--
Sent from my Desktop
Pietro Roversi
EP Abraham Fellow in Biochemistry - Lincoln College - Oxford
Sir William Dunn School of Pathology, Oxford University
South Parks Road, Oxford OX1 3RE, England UK
Tel. 0044-1865-275385
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