/**
  * Returns a structure by its ID.
  *
  * @param int $structureId
  *
  * @return StructureModel|null
  */
 public function getStructureById($structureId)
 {
     $structureRecord = StructureRecord::model()->findById($structureId);
     if ($structureRecord) {
         return StructureModel::populateModel($structureRecord);
     }
 }