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    <p>Which SimNIBS version are you using? In 3.1 we switched to using
      linear interpolation, so these artifacts should not happen
      anymore.</p>
    <p><br>
    </p>
    <p>Best Regards,</p>
    <p>Guilherme<br>
    </p>
    <p><br>
    </p>
    <p><br>
    </p>
    <div class="moz-cite-prefix">On 19/03/2020 10.31, Jane Tan wrote:<br>
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cite="mid:SYBPR01MB524374C30802CDDF6393E5BCA5F40@SYBPR01MB5243.ausprd01.prod.outlook.com">
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        Hi Guilherme,</div>
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        Thanks for the reply. There are a good number of negative values
        (~22.5%).</div>
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        <span style="color: rgb(0, 0, 0); font-family: Calibri, Arial,
          Helvetica, sans-serif; font-size: 12pt;">Do you have any
          suggestions on what I can do to attenuate the artifacts? My
          main aim is to get the mean e-field for specific ROIs.</span></div>
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        <span style="color: rgb(0, 0, 0); font-family: Calibri, Arial,
          Helvetica, sans-serif; font-size: 12pt;">For instance, would
          you recommend the use of normJ instead? I notice that there
          are fewer negative values for normJ, and notably none in the
          ROIs I am interested in. </span></div>
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        <span style="color: rgb(0, 0, 0); font-family: Calibri, Arial,
          Helvetica, sans-serif; font-size: 12pt;">best regards,</span></div>
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        <span style="color: rgb(0, 0, 0); font-family: Calibri, Arial,
          Helvetica, sans-serif; font-size: 12pt;">Jane</span></div>
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      <div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt"
          face="Calibri, sans-serif" color="#000000"><b>From:</b>
          Guilherme B Saturnino <a class="moz-txt-link-rfc2396E" href="mailto:guilhermebs@drcmr.dk"><guilhermebs@drcmr.dk></a><br>
          <b>Sent:</b> Thursday, 19 March 2020 4:08 PM<br>
          <b>To:</b> Jane Tan <a class="moz-txt-link-rfc2396E" href="mailto:Jane.Tan@murdoch.edu.au"><Jane.Tan@murdoch.edu.au></a>;
          <a class="moz-txt-link-abbreviated" href="mailto:discuss@simnibs.org">discuss@simnibs.org</a> <a class="moz-txt-link-rfc2396E" href="mailto:discuss@simnibs.org"><discuss@simnibs.org></a><br>
          <b>Subject:</b> Re: [Simnibs-discuss] normE values in MNI
          space</font>
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        <p>Dear Jane,</p>
        <p><br>
        </p>
        <p><br>
        </p>
        <p>How many negative values are there? This is likely an
          artifact due to spline interpolation of the electric field
          from the original space to MNI space.</p>
        <p><br>
        </p>
        <p>Best Regards,</p>
        <p>Guilherme</p>
        <p><br>
        </p>
        <div class="x_moz-cite-prefix">On 19/03/2020 06.06, Jane Tan
          wrote:<br>
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            Hi SimNIBS Team,</div>
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            I found some negative values in my <span
              style="font-family:Calibri,Arial,Helvetica,sans-serif;
              background-color:rgb(255,255,255);
              display:inline!important">nifti volume for normE in MNI
              space, and I thought something must have gone awry during
              the segmentation process for my head mesh (created <span
                style="font-family:Calibri,Arial,Helvetica,sans-serif;
                background-color:rgb(255,255,255);
                display:inline!important">using headreco (with cat) on a
                MNI152 T1-weighted image)</span>.  However, the head
              mesh looks okay when I checked it with gmsh. The
              headreco_log doesn't seem to indicate any issues either -
              at least not to my untrained eye. I do not have access to
              freeview, and couldn't do a proper check via headreco.</span></div>
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            <span style="font-family:Calibri,Arial,Helvetica,sans-serif;
              background-color:rgb(255,255,255);
              display:inline!important">I'm also wondering if it might
              be due to normE not being very accurate as a result of
              registration to the MNI template? </span></div>
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            <span style="font-family:Calibri,Arial,Helvetica,sans-serif;
              background-color:rgb(255,255,255);
              display:inline!important">Your suggestions would be
              greatly appreciated. I am happy to provide my head mesh
              and segmentation results if that would be of any help.</span></div>
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            <span style="font-family:Calibri,Arial,Helvetica,sans-serif;
              background-color:rgb(255,255,255);
              display:inline!important">best regards,</span></div>
          <div style="font-family:Calibri,Arial,Helvetica,sans-serif;
            font-size:12pt; color:rgb(0,0,0)">
            Jane</div>
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                  <p class="x_MsoNormal" style="margin-top:0px;
                    margin-bottom:0px"><span style="" lang="EN-SG">Best
                      regards,</span></p>
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                    margin-bottom:0px"><span style="" lang="EN-SG"><br>
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                  <p class="x_MsoNormal" style="margin-top:0px;
                    margin-bottom:0px"><span style="" lang="EN-SG">Jane</span></p>
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          <pre class="x_moz-quote-pre">_______________________________________________
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