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<br>
The Fourier Shell Correlation (FSC) is the
standard resolution <br>
curve for three-dimensional reconstructions of single
particles. <span style=""> </span><br>
<br>
A free download of the FSC
program is now available from: <a href="http://www.imagescience.de/fsc">http://www.imagescience.de/fsc
</a>.
<p class="MsoNormal"><o:p></o:p>This distribution is supported by a
grant of the European
Union: FP6 / NOE <a href="http://www.3dem-noe.org/">http://www.3dem-noe.org/.</a></p>
<p class="MsoNormal"><o:p></o:p>This version of the IMAGIC FSC program
is presented with
a Java Graphical User Interface (GUI).<br>
Conversions from 3D data formats other than IMAGIC are possible through
the "import" option<br>
which uses the EM2EM universal EM converter.<br>
</p>
<p class="MsoNormal" style="text-align: justify;"><o:p> </o:p>It was
shown in a recent paper (<span style="" lang="EN-GB">van Heel
M., Schatz M:<b> </b>Fourier Shell Correlation Threshold Criteria,<b> </b><i
style=""><br>
J. Struc. Biol.</i><b> </b>151 (2005)
250-262.</span>), that all fixed value threshold criteria like <b
style=""><br>
“0.5” </b>or<b style=""> “0.143”</b>, are <b style="">incorrect</b>!<span
style=""> </span></p>
<p class="MsoNormal">The better resolution threshold
curve is the <b style="">½-bit curve</b> which is now generated
by the <br>
FSC programs. The program also plots the classical 3-sigma
criterion indicating at <br>
which resolution one has collected data significantly
above the background noise level.<br>
<o:p></o:p><br>
Moreover, the program takes into account all factors
that influence the FSC curve <br>
including: pointgroup symmetry of the structure and its
size within the reconstruction volume. </p>
<p class="MsoNormal"><o:p></o:p>Have fun!</p>
<p class="MsoNormal">Marin van Heel</p>
<pre class="moz-signature" cols="72"><big><big><font
face="Times New Roman"><small>================================================================
Marin van Heel
Professor of Structural Biology
Division of Molecular Biosciences
Faculty of Natural Sciences
Imperial College London
Biochemistry Building
South Kensington Campus
London SW7 2AZ, UK
Tel: + 44 (0)20 7594 5316
Fax: + 44 (0)20 7594 5317
Priv.tel. + 44 (0)20 8286 4248
e_mail: <a class="moz-txt-link-abbreviated" href="mailto:m.vanheel@ic.ac.uk">m.vanheel@ic.ac.uk</a>
and: Osnat Lipson <a class="moz-txt-link-rfc2396E" href="mailto:vanheel.office@ic.ac.uk"><vanheel.office@ic.ac.uk></a>
web: <a class="moz-txt-link-abbreviated" href="http://www.cbem.ic.ac.uk">www.cbem.ic.ac.uk</a>
</small></font></big></big>
</pre>
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