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": ""}
   i nigrescens  contact um herbarium k/7   2I^8 CANADA  CENTAUAE NIGRESCENS 4?   ontario /M        +8S 1970-09-04   ;D 1284721  ASTERALES ) >        o&TnQ CENTAUREA  a  Asteracea   ^|; anton a. reznicek SIMCOE z - 
{"catalogNumber": "1284721", "order": "Asterales", "family": "Asteraceae", "scientificName": "Centaurea nigrescens", "scientificNameAuthorship": "", "genus": "Centaurea", "subgenus": "", "specificEpithet": "nigrescens", "verbatimTaxonRank": "", "infraspecificEpithet": "", "identifiedBy": "", "recordedBy": "Anton A. Reznicek", "recordNumber": "", "verbatimEventDate": "1970-09-04", "habitat": "", "occurrenceRemarks": "", "associatedTaxa": "", "country": "Canada", "stateProvince": "Ontario", "county": "Simcoe", "municipality": "", "locality": "Contact UM Herbarium", "decimalLatitude": "", "decimalLongitude": "", "verbatimCoordinates": "", "minimumElevationInMeters": "", "maximumElevationInMeters": ""}