It's in Nature Scientific Reports. Not the same journal as it's better known sibling, and it takes the megajournal approach of not judging notability, only rigour.
That said, the reputation of any journal is a poor predictor of the impact of papers published in it, so you shouldn't judge. In fact that's why megajournals like nature scientific reports, plos one and peerj have become so popular.
That's what I was wondering as well, this is obviously a study done on a very small budget with conclusions that could be called a stretch but maybe they knew that research in that area gets more attention?