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<p class="MsoNormal">Hej Linda! <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I had similar precipitates a while ago and it took me forever to find the source. For us, it was that the oil filter on the glow discharger that needed to be changed. Try just putting an empty grid in the glow discharger and then have a
look at it to exclude this possibility. <o:p></o:p></p>
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<p class="MsoNormal">Good luck! <o:p></o:p></p>
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<p class="MsoNormal">Johanna<o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">3dem <3dem-bounces@ncmir.ucsd.edu> on behalf of Linda Sandblad <linda.sandblad@umu.se><br>
<b>Date: </b>Sunday 24 September 2017 23:27<br>
<b>To: </b>"3dem@ncmir.ucsd.edu" <3dem@ncmir.ucsd.edu><br>
<b>Subject: </b>[3dem] negative staining artifact<o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hi all experts!!<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I know, this do not look nice, but I would like to hear your opinion about this artifact. Tiny dark spots covering both sample and background, do you know what it is, were it comes
from and how to avoid it? We have this bad background time to time from different labs…. It is a “normal” negative staining protocol: copper grids, formvar, carbon, glow discharge, UA.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I’m happy for your suggestions, Best Linda<o:p></o:p></p>
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<p class="MsoNormal"><span style="color:black">Linda Sandblad<br>
……………………………………………….</span><span style="font-family:"PMingLiU",serif;color:black"><br>
</span><span style="color:black">Department of Molecular Biology</span><span style="font-family:"PMingLiU",serif;color:black"><br>
</span><span style="color:black">Umeå University</span><span style="font-family:"PMingLiU",serif;color:black"><br>
</span><span style="color:black">+46 709324936<o:p></o:p></span></p>
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