How the end of smallpox contributed to the mpox outbreak

Hello Nature readers,
Today we learn intimate details of the molecular meet-cute between sperm and eggs, meet the world’s most powerful resistive magnet and discover how the eradication of smallpox influenced the spread of mpox.

How sperm and egg hook up

Researchers have identified three proteins that work together as matchmakers between sperm and egg cells. They used the artificial-intelligence tool AlphaFold to predict the interactions between proteins of sperm cells. It predicted that three such proteins form a complex, which creates a place for an egg protein to bind. “It’s not the old concept of having a key and a lock to open the door anymore,” says reproductive biologist Enrica Bianchi. “It’s more complicated.”

Mega-magnet breaks field record

A magnet at the Steady High Magnetic Field Facility (SHMFF) in China has sustained a steady magnetic field of 42.02 tesla, which is more than 800,000 times stronger than Earth’s — making it the world’s most powerful resistive magnet. High-field magnets are handy tools for uncovering hidden properties of advanced materials, such as superconductors, and could offer researchers glimpses of entirely new physical phenomena. The drawback is the power these mammoth magnets consume: the SHMFF’s magnet used 32.3 megawatts of electricity to produce its record-breaking field. “You’ve got to have a very good science case to justify that resource,” says condensed-matter physicist Alexander Eaton.

How the end of smallpox led to mpox

“We vaccinated for smallpox and eradicated it. But look, something came out of that: monkeypox,” said Uganda’s health minister, Jane Ruth Aceng, in August. Smallpox and mpox are closely related diseases — having immunity to one boosts immunity to the other. Once smallpox was eradicated, and the vaccination campaigns halted, population immunity to both diseases waned. Researchers were aware of this risk, but at the time, mpox wasn’t seen as a big enough threat. Now, African nations are scrambling to rebuild the medical expertise to diagnose and treat mpox outbreaks; skills that disappeared along with the vaccines.

Don’t skip your coffee breaks

Chemist turned science journalist Victoria Atkinson is championing the humble coffee break. Stepping out of the lab for a moment, she writes, is far from a waste of time. In fact, her breaks with colleagues during her master’s and PhD was where the real learning began — helping her to pick up the lab tips and tricks she didn’t get in the classroom.

Futures: A sequence of memories

An 89-year-old considers what it means to be home as she watches her life play before her eyes in the latest short story for Nature’s Futures series.

Podcast: An unusual microquasar

A type of binary-system called a microquasar has been found to be firing out γ-rays at high energy-levels, evidence that it might be a long-theorized natural particle-accelerator known as a PeVatron. These objects are thought to be a source of galactic cosmic rays, the origins of which are currently a mystery. “Supernova explosions have been good candidates for accelerating these cosmic rays and people haven't really considered microquasars, at least not recently,” says astrophysicist Jamie Holder, who wrote about the paper in the accompanying Nature News & Views article. “So this is kind of revitalizing this idea that maybe these types of systems could contribute as well.”