Is this sewage outlet the "fountain of youth"?
Is this the fountain of youth?
The small waterway behind Nottingham's Queens Medical Centre looks unspectacular, but may help unlock the secret to increasing human lifespans.
Scientist Aziz Aboobaker and fellow researchers use the outlet as a source of planaria (flatworms).
They say the worms are helping us understand stem cells and leading to advances in human medicine.
The planaria are special because they have a high proportion of adult stem cells, with Dr Aboobaker nicknaming them "immortal worms".
He says: "The coolest thing is that we can take a worm in the lab, chop its head off, and within seven days the worm has grown a whole new brain.
"That's an incredible thing.
Aziz Aboobaker studies flatworms
"The brain even in a simple worm like that is incredibly complex with thousands of cells that all have to be in the right place and all know what they're doing.
"And don't worry about the head (that was chopped off), it just re-grows a new tail and crawls off."
It is hoped understanding these powers of regeneration in flatworms will lead to breakthroughs with human stem cells.
Adult human stem cells are limited compared to their worm counterparts.
Dr Aboobaker says: "If you make a small wound in (human) skin, sure we can cope with that.
Aziz thinks the worms are 'cute'
"But if we lose a whole piece of tissue, like an organ or limb, we don't know how to (re-grow) that.
"That's one of the reasons we are so interested in the flatworms, because they've figured out how to do that."
Planaria are common and Dr Aboobaker's team regularly take them from the sewage outlet at the QMC because it is convenient.
However many other flatworms used for their research are shipped from Spain.
So how does Dr Aboobaker, from the University of Nottingham, feel about working with the tiny creatures?
"They're really cute," he says.
"They have big cartoon character eyes and they're easy to look after - and they don't die."