For much of the 21st century, one theory has dominated research efforts to cure Alzheimer's disease: the amyloid hypothesis. Beta-amyloid is a protein that builds up in clumps, or plaques, in the brains of people with Alzheimer's disease and is linked to their cognitive decline.

But in recent years, despite the emergence of a couple of new drugs targeting these plaques, some scientists have begun to doubt the amyloid hypothesis. Donald Weaver, a professor of chemistry at the University of Toronto in Canada, is one of them.

Weaver no longer believes there will be one magic bullet found to cure Alzheimer’s disease. Instead, he advocates for a magic shotgun approach that is likely to involve multiple ways of treating the problem, including starting much earlier in a person’s life. He tells us about shifts in the understanding of Alzheimer's during his career of more than 30 years, and the theories now emerging about what might cause the disease and how to treat it.

This episode was written and produced by Katie Flood with assistance from Mend Mariwany. Gemma Ware is the host and executive producer. Sound design and mixing by Eloise Stevens and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.

If you like the show, please consider donating to The Conversation, an independent, not-for-profit news organisation.

Three months after the Trump administration made drastic cuts to its aid agency, USAID, the effects are being felt across the world, particularly in Africa. In this episode we speak to Bright Simons, an African aid expert and visiting senior fellow at ODI Global about where the decimation of US aid leaves the debate about the future of development assistance.

This episode of The Conversation Weekly was written and produced by Mend Mariwany and Gemma Ware. Mixing and sound design by Eloise Stevens and theme music by Neeta Sarl. Read the full credits for this episode and sign up here for a free daily newsletter from The Conversation.

If you like the show, please consider donating to The Conversation, an independent, not-for-profit news organisation.

• USAID’s apparent demise and the US withdrawal from WHO put millions of lives worldwide at risk and imperil US national security
• USAID: the human cost of Donald Trump’s aid freeze for a war-torn part of Sudan

Liverpool FC just won the English Premier League. Contributing to their 5-1 victory over Tottenham to seal the title was Mohamed Salah, the Egyptian superstar who is the league's top scorer in the 2024-5 season.

We're revisiting an episode that we first ran in December 2022 about research which used Salah to demonstrate how a celebrity footballer who is openly Muslim can help to reduce Islamophobia. Salma Mousa, now an assistant professor of political science at UCLA in the US, talks to us about her research.

This episode was produced and written by Gemma Ware, with sound design by Eloise Stevens. Our other producers are Mend Mariwany and Katie Flood. Our theme music is by Neeta Sarl. More details can be found in an article that accompanied the original episode.