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.

The Trump administration’s cuts to funding for American universities and research have left many scientists reeling and very worried. At the National Institutes of Health, which has an annual budget of US$47 billion to support medical research both in the U.S. and around the world, nearly 800 grants have been terminated. The administration is considering cutting the overall budget of the NIH by 40%.

In this episode, we speak to three scientists, Brady West and Sunghee Lee from the University of Michigan in the US, and Glenda Gray, an expert in HIV vaccines from the University of Witwatersrand in South Africa, about what it’s like to have funding cut by the Trump administration.

This episode was written and produced by Gemma Ware and Katie Flood. 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.

Few places on earth are immune to the explosion of anti-vaccination conspiracy theories and health disinformation fuelled by the COVID pandemic. But in countries like Brazil, where the disinformation flowed from the very top of government, the problem is even more acute and some people are exploiting the fear of others to make money.

In this episode we speak to Ergon Cugler at the Brazilian Institute of Information on Science and Technology about his new research into how peddlers of disinformation on social media also sell fake cures and vaccine detoxes. And we ask disinformation researcher Igor Sacramento at Brazil's Oswaldo Cruz Foundation why some people are looking for solutions to their health problems in these dangerous chemicals and unproven protocols.

This episode was written and produced by Gemma Ware with assistance from Mend Mariwany. 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.

The Birkin bag made by French luxury retailer Hermès has become a status symbol for the global elite. Notoriously difficult to obtain, the world's rich obsess over how to get their hands on one. But when US retailer Walmart recently launched a much cheaper bag that looked very similar to the Birkin, nicknamed a "Wirkin" by others, it sparked discussions about wealth disparity and the ethics of conspicuous consumption.

In this episode we speak to two sociologists, Parul Bhandari from the University of Cambridge in the UK and Aarushi Bhandari from Davidson College in the US, about the Birkin and what it symbolises.

This episode was written and produced by Katie Flood. 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.

• Birkin bags, Swiss ski resorts and Louis Vuitton: how super-rich Delhi housewives strive to be part of a global elite
• Birkin handbags, Walmart’s ‘Wirkin’ and the meme-ification of class warfare

Some of the leading brains behind generative AI have warned about the risk of artificial superintelligence wiping out humanity, if left unchecked. But what if the influence of AI on humans is much more mundane, influencing our evolution over thousands of years through natural selection?

In this episode we talk to evolutionary biologist Rob Brooks about what AI could do to the evolution of humanity, from smaller brains to fewer friends.

This episode was written and produced by Gemma Ware. Sound design was 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.

Five years since Covid, not only has the pandemic affected the way we live and work, it’s also influencing the way researchers are thinking about the past.

In this episode archaeologist Alex Bentley from the University of Tennessee explains how the pandemic sparked new research into how disease may have affected ancient civilisations, and the clues this offers about a change in the way humans designed their villages and cities 8,000 years ago.

This episode was written and produced by Katie Flood and hosted by Gemma Ware. Sound design was 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.

• Celibacy: family history of Tibetan monks reveals evolutionary advantages in monasticism – podcast
• Socially distanced layout of the world’s oldest cities helped early civilization evade diseases