Shereen El Feki

Laws that treat people living with HIV or those at greatest risk with respect start with the way that we treat them ourselves: as equals. If we are going to stop the spread of HIV in our lifetime, then that is the change we need to spread.

In Egypt, where my research is focused, I have seen plenty of trouble in and out of the citadel. There are legions of young men who can't afford to get married, because marriage has become a very expensive proposition. They are expected to bear the burden of costs in married life, but they can't find jobs.

My mother's family is Christian: her father was a Baptist lay preacher, and her brother, in a leap of Anglican upward mobility, became a vicar in the Church of Wales. But my mother converted to Islam on marrying my father. She was not obliged to; Muslim men are free to marry ahl al-kitab, or people of the Book - among them, Jews and Christians.

Supplying fuel for a Mars expedition from the lunar surface is often suggested, but it's hard to make it pay off - Moon bases are expensive, and just buying more rockets to launch fuel from Earth is relatively cheap.

Despite all the hype about local or green food, the single biggest impediment to wider adoption is not research, programs, organizations, or networking. It is the demonizing and criminalizing of virtually all indigenous and heritage-based food practices.