Acne is the bane of teenagers, but it also affects adults. In the latest edition of Periodic Graphics in Chemical & Engineering News, we look at the causes of acne and some medications used to treat it. Click here to view the full graphic.
The Muslim festival of Eid al-Adha started on Sunday evening and runs through until Thursday. As part of the celebrations, some create impressively intricate art on their hands using henna. Here we take a look at the molecules in henna that allow it to be used as a dye, and how this process works.