Refactor the unstructured text into a valid JSON dictionary. The key names follow the Darwin Core Archive Standard. If a key lacks content, then insert an empty string. Fill in the following JSON structure as required: {"catalogNumber": "", "order": "", "family": "", "scientificName": "", "scientificNameAuthorship": "", "genus": "", "subgenus": "", "specificEpithet": "", "verbatimTaxonRank": "", "infraspecificEpithet": "", "identifiedBy": "", "recordedBy": "", "recordNumber": "", "verbatimEventDate": "", "habitat": "", "occurrenceRemarks": "", "associatedTaxa": "", "country": "", "stateProvince": "", "county": "", "municipality": "", "locality": "", "decimalLatitude": "", "decimalLongitude": "", "verbatimCoordinates": "", "minimumElevationInMeters": "", "maximumElevationInMeters": ""}
   4+ _  1998-04-20             7971    Bryan E   s Rb` HENDRIX POST OFFICE ON RIVER ROAD, 3.9 MILES EAST.   (small) mack.  C    ! 1362840 austrina np    
{"catalogNumber": "1362840", "order": "", "family": "", "scientificName": "", "scientificNameAuthorship": "(Small) Mack.", "genus": "", "subgenus": "", "specificEpithet": "austrina", "verbatimTaxonRank": "", "infraspecificEpithet": "", "identifiedBy": "", "recordedBy": "", "recordNumber": "7971", "verbatimEventDate": "1998-04-20", "habitat": "", "occurrenceRemarks": "", "associatedTaxa": "", "country": "", "stateProvince": "", "county": "Bryan", "municipality": "", "locality": "Hendrix Post Office on River Road, 3.9 miles east.", "decimalLatitude": "", "decimalLongitude": "", "verbatimCoordinates": "", "minimumElevationInMeters": "", "maximumElevationInMeters": ""}