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<subj-group> Subject Group

Container element for the subject matter designations describing a document’s content or a component document’s content. Subjects are used to organize documents into groupings (potentially hierarchical groupings) for display or print.

Usage/Remarks

Subjects (and groupings of subjects) are used, typically, to provide headings for groups of documents or document components in a printed, or online, generated Table of Contents.
For some journals, articles are grouped into categories which this Tag Set calls <subject>s, which may be grouped into <subj-group>s. These subject categories are typically shown in the Table of Contents, at the top of the first print or display page, or on the web splash page for an article. Sometimes the grouping or category refers to the type of article, such as “Essay”, “Commentary”, “Obituary”, “Award”, or “Article”. Sometimes the grouping refers to subject areas, such as “Physical Sciences”, “Biological Sciences”, or “Social Sciences”. Sometimes the grouping refers to topics within the larger subject areas, such as “Applied Math”, “Biology”, or “Chemistry”. For example, a one-level grouping might be: 
<subj-group>
  <subject>Retraction</subject>
</subj-group>
or, as another example:
<subj-group>
  <subject>Essay</subject>
</subj-group>
And a four-level grouping might be:
<article-categories>
  <subj-group subj-group-type="classification"> 
    <subject>Biological Sciences</subject>
    <subj-group>
      <subject>Neuroscience</subject>
      <subj-group>
        <subject>Cellular and Molecular Biology</subject>  
        <subj-group>
          <subject>Blood&ndash;brain barrier</subject>
        </subj-group>
      </subj-group>
    </subj-group>
  </subj-group> 
</article-categories>
Articles may also be assigned to more than one grouping. For example, if an article is classified as “Biochemistry” under “Biological Sciences” and “Chemistry” under “Physical Sciences”, the <subj-group> container element may repeat. For example: 
<subj-group>
  <subject>Articles</subject>
  
  <subj-group>
    <subject>Biological Sciences</subject>
  
    <subj-group>
      <subject>Biochemistry</subject>
    </subj-group>
  </subj-group>
  
  <subj-group>
    <subject>Physical Sciences</subject>
  
    <subj-group>
      <subject>Chemistry</subject>
    </subj-group>
  </subj-group>
</subj-group>

Attribute Best Practice

If the content of the <subj-group> element is a term from a taxonomy, ontology, term-list, vocabulary, industry glossary, or other known source, then the vocabulary attributes should be used to record that source. This source can be a formal ontology or an informal field of study. Two attributes are used in this Tag Set to identify such a controlled or uncontrolled vocabulary:
vocab
Name of the controlled or uncontrolled vocabulary, taxonomy, ontology, index, database, or similar that is the source of the term. For example, for a subject term, a value might be the IPC Codes (“ipc”) or MESH headings (“mesh”). For an uncontrolled term, the value might be an area of study such as “medical-devices” or merely the word “uncontrolled”.
vocab-identifier
Unique identifier of the vocabulary, such as (but not limited to) a URI or DOI. For example, for Dublin Core (DCC), the identifier may be “http://dublincore.org/documents/2012/06/14/dces/”.
Attributes
assigning-authority
specific-use
subj-group-type
vocab
vocab-identifier

Base Attributes

id
xml:base
xml:lang
Models and Context
May be contained in
<ack>, <app-group>, <article-categories>, <chem-struct-wrap>, <disp-formula>, <disp-formula-group>, <fig>, <fig-group>, <graphic>, <media>, <sec-meta>, <statement>, <subj-group>, <supplementary-material>, <table-wrap>, <table-wrap-group>
Description
The following, in order:
Content Model
<!ELEMENT  subj-group   %subj-group-model;                           >
Expanded Content Model

((subject | compound-subject)+, subj-group*)

Tagged Samples
Article categorizations 
...  
<article-categories>
 <subj-group>
  <subject>ISO/TC 43</subject>
  <subj-group>
   <subject>SC 1, Noise</subject>
  </subj-group>
 </subj-group>
</article-categories>
...
...
<article-categories>
 <subj-group subj-group-type="classification">
  <subject content-type="neurosci">Cellular and Molecular
   Biology</subject>
  <subj-group>
   <subject content-type="neurosci">Blood&ndash;brain
    barrier</subject>
  </subj-group>
 </subj-group>
</article-categories>
...
Table of Contents grouping 
...  
<article-categories>
 <subj-group subj-group-type="toc-heading">
  <subject>ARTICLES</subject>
  <subj-group>
   <subject>Structural, Mechanical, Thermodynamic, and Optical 
    Properties of Condensed Matter</subject>
  </subj-group>
 </subj-group>
</article-categories>
...
One article, many subject groups 
<article dtd-version="1.3">
 <front>
  <journal-meta>...</journal-meta>
  <article-meta>
   ...
   <article-id pub-id-type="pmid">11274384</article-id>
   <article-categories>
     <subj-group>
       <subject>Physical Sciences</subject>
       <subj-group>
         <subject>Chemistry</subject>
       </subj-group>
     </subj-group>

     <subj-group>
       <subject>Biological Sciences</subject>
       <subj-group>
         <subject>Biophysics</subject>
       </subj-group>
     </subj-group>
   </article-categories>
   <title-group>...</title-group>
   ...
  </article-meta>
 </front>
 <body>...</body>
 <back>...</back>
</article>
...
<article-categories>
 <subj-group>
  <subject>Departments</subject>
  <subj-group>
   <subject>Federal Court Decisions</subject>
   <subj-group>
    <subject>Supreme Court Opinions</subject>
    <subj-group>
     <subject>Criminal Procedure</subject>
     <subj-group>
      <subject>Fourth Amendment:  Search and Seizure</subject>
      <subj-group>
       <subject>Vehicle Passenger Rights: <italic>Brendlin v.
        California</italic></subject>
      </subj-group>
     </subj-group>
    </subj-group>
   </subj-group>
   <subj-group>
    <subject>4th Circuit Decisions</subject>
    <subj-group>
     <subject>Habeas Corpus</subject>
     <subj-group>
      <subject>Detaining U.S. Residents: <italic>Al-Marri v.
       Wright</italic></subject>
     </subj-group>
    </subj-group>
   </subj-group>
  </subj-group>

  <subj-group>
   <subject>Federal Law</subject>
   <subj-group>
    <subject>Changes to FISA Surveillance:  Protect America Act of
     2007</subject>
   </subj-group>
  </subj-group>

  <subj-group>
   <subject>Ethical Guidelines</subject>
   <subj-group>
    <subject>Protecting Client Confidences</subject>
    <subj-group>
     <subject>Potential for Identity Theft in Pleadings and
      Filings</subject>
     <subj-group>
      <subject>Drivers License Numbers</subject>
     </subj-group>
     <subj-group>
      <subject>Social Security Numbers</subject>
     </subj-group>
    </subj-group>
   </subj-group>
  </subj-group>

 </subj-group>
</article-categories>
...
Recording a taxonomy 
...
<subj-group subj-group-type="System Taxonomy">
 <subject>Drosophila</subject>
</subj-group>
...
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