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<p class=MsoNormal><font size=4 face="Times New Roman"><span style='font-size:
14.0pt'><!-- Converted from text/enriched format -->Dear Dr. Bill Tivol,</span></font></p>
<p class=MsoNormal><font size=4 face="Times New Roman"><span style='font-size:
14.0pt'> </span></font></p>
<p class=MsoNormal style='line-height:150%'><font size=4 face="Times New Roman"><span
style='font-size:14.0pt;line-height:150%'>You are so right that the</span></font>
<font size=4><span style='font-size:14.0pt;line-height:150%'>maximum ice
thickness for imaging depends on the HT of the scope. I sent a message to Paul asking
about the specific HT of 100 Kv. Hopefully He would tell me a number. Of
course, I’d be happier if our colleagues could tell me the numbers not
only of 100 Kv, but also of 200 Kv, 300 Kv and 400 Kv.</span></font></p>
<p class=MsoNormal style='line-height:150%'><font size=4 face="Times New Roman"><span
style='font-size:14.0pt;line-height:150%'>Thanks!</span></font></p>
<p class=MsoNormal style='line-height:150%'><font size=4 face="Times New Roman"><span
style='font-size:14.0pt;line-height:150%'> </span></font></p>
<p class=MsoNormal style='line-height:150%'><font size=4 face="Times New Roman"><span
style='font-size:14.0pt;line-height:150%'>Regards,</span></font></p>
<p class=MsoNormal style='line-height:150%'><font size=4 face="Times New Roman"><span
style='font-size:14.0pt;line-height:150%'>Guobin</span></font></p>
<p class=MsoNormal style='line-height:150%'><font size=4 face="Times New Roman"><span
style='font-size:14.0pt;line-height:150%'> </span></font></p>
<p class=MsoNormal><font size=4 face="Times New Roman"><span style='font-size:
14.0pt'> </span></font></p>
<p class=MsoNormal><font size=4 face="Times New Roman"><span style='font-size:
14.0pt'> </span></font></p>
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10.0pt;font-family:Arial;color:navy'> </span></font></p>
<p class=MsoNormal style='margin-left:.5in'><font size=2 face=Tahoma><span
style='font-size:10.0pt;font-family:Tahoma'>-----Original Message-----<br>
<b><span style='font-weight:bold'>From:</span></b> owner-3dem@ncmir.ucsd.edu
[mailto:owner-3dem@ncmir.ucsd.edu] <b><span style='font-weight:bold'>On Behalf
Of </span></b>Bill Tivol<br>
<b><span style='font-weight:bold'>Sent:</span></b> </span></font><font size=2 face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>Thursday,
February 17, 2005</span></font><font size=2 face=Tahoma><span
style='font-size:10.0pt;font-family:Tahoma'> </span></font><font
size=2 face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>1:01 PM</span></font><font
size=2 face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'><br>
<b><span style='font-weight:bold'>To:</span></b> 3dem@ucsd.edu<br>
<b><span style='font-weight:bold'>Subject:</span></b> Re: [3DEM] A question
about ice thickness of cryo-EM</span></font></p>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'> </span></font></p>
<p class=MsoNormal style='margin-right:0in;margin-bottom:12.0pt;margin-left:
.5in'><font size=3 face="Times New Roman"><span style='font-size:12.0pt'> </span></font></p>
<div>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>On </span></font>Feb 17, 2005, at 9:34 AM, Hu, Guobin wrote: </p>
</div>
<blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'> </span></font></p>
<div>
<p class=MsoNormal style='margin-left:.5in'><font size=6 color=navy
face="Times New Roman"><span style='font-size:24.0pt;color:navy'>Thanks for
your information! You might have given me a basic idea what the maximum of ice
thickness could be. Actually as indicated in my earliest message,
I’m not trying to figure out how thick the ice could be in any specific
case. What I’m trying to find out is an estimate of the maximum of ice
thickness of cryo-EM grids which is good enough for imaging. I wonder if
anybody has ever collected data with ice thicker than 800 nm.</span></font></p>
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</blockquote>
<blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'>
<p class=MsoNormal style='margin-right:0in;margin-bottom:12.0pt;margin-left:
.5in'><font size=3 face="Times New Roman"><span style='font-size:12.0pt'> </span></font></p>
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<p class=MsoNormal style='margin-left:.5in'><font size=6 color=navy
face="Times New Roman"><span style='font-size:24.0pt;color:navy'>Thanks for any
further help!</span></font></p>
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</blockquote>
<blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'> </span></font></p>
</blockquote>
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<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>Dear Guobin, </span></font></p>
</div>
<div>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>The maximum ice thickness for imaging depends on the
HT of your scope. We have been imaging small whole cells at 300 kV, and we can
do tomography on cells that are a little smaller than 1 um. Of course, the ice
may not be that thick except in the immediate neighborhood of the cell, and the
resolution should improve for thinner ice, so the answer to "Is the ice
too thick for imaging?" is "It depends on what you're trying to do
and what equipment you have to do it." </span></font></p>
</div>
<div>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>Yours, </span></font></p>
</div>
<div>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>Bill Tivol, PhD </span></font></p>
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<div>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>EM Scientist and Manager </span></font></p>
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<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>Cryo-Electron Microscopy Facility </span></font></p>
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<div>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>Broad</span></font> Center, Mail Code 114-96 </p>
</div>
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<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>California Institute of Technology </span></font></p>
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<div>
<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>Pasadena</span></font> CA 91125 </p>
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<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>(626) 395-8833 </span></font></p>
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<p class=MsoNormal style='margin-left:.5in'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>tivol@caltech.edu </span></font></p>
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