Special Editions

Fluoride is the stuff in toothpaste that helps strengthen teeth. But if there's too much fluoride in the water it softens bones, and children become susceptible to bone deformities. It's very difficult and expensive to remove dissolved fluoride ions from water. But, inspired by nature, scientists have used polymers to produce a membrane that can filter out fluoride, as Sally Le Page heard from Ayse Asatekin... Like this podcast? Please help us by supporting the Naked Scientists

Twitter has been the subject of another study, looking at how people's tendency to post tweets in moral outrage is affected by other people on the site. Increasingly in recent years, celebrities and other well-known individuals have found themselves being "cancelled". This usually happens when they do or say something that other users disagree with. The outpourings of outrage reverberate across the social network with many piling in publicly to scorn and humiliate the perpetrator. But why do people resort to this Twitter equivalent of lobbing rotten tomatoes at someone in the stocks?... Like this podcast? Please help us by supporting the Naked Scientists

Scientists and doctors are always after good quality human cells for research and therapeutic purposes, but these can be hard to come by in sufficient quantities. Now, synthetic biology company bit.bio has opened up new headquarters in Cambridge to start supplying multiple different cell types by reprogramming stem cells. Eva Higginbotham heard more from founder and CEO Mark Kotter... Like this podcast? Please help us by supporting the Naked Scientists

Many of us love putting out bird seed and watching birds feast away, and feel we're doing a good deed too, but a new paper out of Manchester Metropolitan University suggests we may actually be doing more harm than good. Eva Higginbotham spoke to BBC science correspondent Victoria Gill, who spoke with lead author Alex Lees previously... Like this podcast? Please help us by supporting the Naked Scientists

Most schools across the UK are open and children are heading back to their classrooms. But to what extent will this affect the Covid case rates across the country and what can we do to avoid disrupting a third academic year? In Scotland, children returned to school sooner than their English counterparts: what can we learn from their experience? Chris Smith spoke with Linda Bauld, who specialises in public health at the University of Edinburgh... Like this podcast? Please help us by supporting the Naked Scientists

Quite soon after the pandemic first struck a significant number of people began to complain of persistent symptoms in the aftermath of being infected with the new coronavirus. These manifestations have been dubbed "long covid". What's less clear is the extent to which this is happening not just to adults but also to children, and particularly teenagers. Terence Stephenson is at the UCL Gt Ormond St Institute of Child Health and spoke with Chris Smith... Like this podcast? Please help us by supporting the Naked Scientists

We often look for water on remote planets and moons because, as far as we know, it's a requirement for life. Now a team of researchers using the Hubble Space Telescope to scrutinise Jupiter's largest moon, Ganymede, think they've found water in its atmosphere. Sally Le Page spoke with team member Kurt Retherford. Like this podcast? Please help us by supporting the Naked Scientists

Is Delta more deadly, or just transmitting more rapidly? And are the vaccines we're using likely to defend against future coronavirus variants? Also, does it matter that levels of antibody dimish post-vaccination, or will immune memory make up for the shortfall? Meanwhile, are vaccinated people who still catch Delta equally infectious? Does Delta incubate at the same rate as classical coronavirus strains? And do tests work equally well against Delta? Like this podcast? Please help us by supporting the Naked Scientists

Researchers have reported a case of antibiotic-resistant bacteria passing between dogs and their owners. And these bacteria aren't just resistant to any antibiotic - they're resistant to colistin, an antibiotic of last resort that we use when all other treatments fail. Mark Holmes is a vet and a microbial scientist from the University of Cambridge - he wasn't involved in the research, but he took a look for us and spoke to Eva Higginbotham... Like this podcast? Please help us by supporting the Naked Scientists

Chris Smith joins Radio New Zealand National's Kim Hill to talk Covid-19, including the impact of the July 19th UK Freedom Day on Covid case rates. They also touch on vaccine performance, variants, past pandemics and whether we'll all be getting boosters in future years... Like this podcast? Please help us by supporting the Naked Scientists