The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on scientific creativity and progress to give you a therapeutic dose of inspiration headed into the weekend.Here are the promising studies covered in this week's Friday Five:- A new "polypill" regimen for prevent second heart attacks- The best kind of plant for sucking toxins out of the air- Diamonds, explosions and invisible medicine- How to brew up a cancer drug in the lab- AI knows if you have Parkinson's before doctors do The honorable mention for this week's Friday Five: blue light could be having a much bigger effect than we thought.