Fix worker function signature
Fix worker function signature

Dallinger/Dallinger,Dallinger/Dallinger,Dallinger/Dallinger,jcpeterson/Dallinger,berkeley-cocosci/Wallace,Dallinger/Dallinger,jcpeterson/Dallinger,jcpeterson/Dallinger,suchow/Wallace,jcpeterson/Dallinger,jcpeterson/Dallinger,suchow/Wallace,suchow/Wallace,berkeley-cocosci/Wallace,berkeley-cocosci/Wallace,Dallinger/Dallinger