Remarks

Supplementary material has been defined to include all of the following:

• Voluminous material (such as a genomic database or the multiple data sets behind a work that abstracts the highlights of those datasets) that supports the conclusions of the narrative but can never accompany a document based on sheer mass.
• “Extra” tables that do not display with the work, but that record the measurements on which the document is based, for example, that need to be available so the peer reviewers can check the document content.
• Material added to the work for enhancement purposes, such as a quiz, an instructional video, the 3-minute version of the reaction that was described in the work with narrative and a few still images, a form that can be filled out or copied, etc.
• A preview image (for example, the first frame of a movie, tagged as a <graphic> or <media>), with the caption/preview placed in a manner similar to a <fig> and a cross-reference made to the material from the text.
• The last 5 figures of the work.

Usage: The element is used in two contexts:

• Inside the document metadata as an alert to the existence of supplementary material so that such material can be accessed from the document; and
• As part of the textual narrative flow, where it is similar to a <fig>, in that it can be positioned as a floating or anchored object and may take a caption.
  For this usage, the @position attribute may be used to indicate whether the element must be anchored at its exact location within the text or whether it may float, for example, to the top of the next page, into the next column, to the end of a logical file, or within a separate window.

Typing: The @mimetype attribute may be used to identify a file type for a <supplementary-material> element.

Relation to Other Tag Sets: The <supplementary-material> element has a similar function to the <audiovisual> element in some XML tag sets and the <unprinted-item> element (used only for electronic files) in other tag sets.

<!ELEMENT  supplementary-material
                        %supplementary-material-model;               >

          
...
<sec>
...
<p>The molecular determinants of transcription-complex stability
and processivity are understood poorly. Several competing
mechanistic models of RNAP function have been proposed ...</p>
<supplementary-material id="S1"
xmlns:xlink="http://www.w3.org/1999/xlink"
xlink:title="local_file"
xlink:href="1471-2105-1-1-s1.pdf"
mimetype="application/pdf">
<label>Additional material</label>
<caption>
<p>Supplementary PDF file supplied by authors.</p>
</caption>
</supplementary-material>
<p>RNAPs seem to have arisen twice in evolution (see the
<inline-supplementary-material
xmlns:xlink="http://www.w3.org/1999/xlink"
xlink:title="local_file" xlink:href="timeline">Timeline
</inline-supplementary-material>. A large family of multisubunit
RNAPs includes bacterial enzymes, archeal enzymes, eukaryotic
nuclear RNAPs, plastid-encoded chloroplast RNAPs, and RNAPs
from some eukaryotic viruses. Members of this family exhibit
extensive sequence and structural similarities ...</p>
</sec>
...