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Muon g-2 experiment at Fermilab

The storage-ring magnet used for the g – 2 experiment at Fermilab.Credit: Reidar Hahn/Fermilab

Muon experiment nears moment of truth

A result that has been 20 years in the making could reveal the existence of new particles and upend fundamental physics. Physicists have high hopes that the magnetism of muons, measured in the Muon g – 2 experiment and scheduled to be released on 7 April, will uphold sensational findings first announced in 2001. The project’s earlier results hinted that the muon’s magnetic moment — a measure of the magnetic field it generates — is slightly larger than theory had predicted. If that finding is ultimately confirmed, it could help to reveal what kinds of ephemeral, unknown ‘virtual particles’ swirl in the vacuum.

Nature | 6 min read

The hunt for new physics: Showing how the Muon g-2 experiment has been looking for virtual particles by observing muons.

Source: Adapted from go.nature.com/2naoxaw

1,209 years

The time period over which the peak date of Japan’s cherry-blossom season has been recorded. This year’s peak was on 26 March, the earliest ever. (BBC | 3 min read)

COVID-19 coronavirus update

WHO report zeroes in on animal markets

Markets that sold animals — some dead, some alive — in December 2019 have emerged as a probable source of the coronavirus pandemic in a major investigation organized by the World Health Organization (WHO). That investigation winnowed out alternative hypotheses on when and where the pandemic arose, and it concluded that the virus probably didn’t spread widely before December or escape from a laboratory. The investigation report, released today, also takes a deep look at markets’ role — including the Huanan market in Wuhan, to which many of the first known COVID-19 infections are linked.

Nature | 6 min read

Reference: WHO report: Origins of the SARS-CoV-2 virus

After reading the 320-page report on the international investigation into COVID-19’s origins, I came away wanting more studies on the market-origin hypothesis. Fourteen countries apparently felt the same, posting a letter after the report went live, requesting “phase 2” studies and demanding greater transparency from China so that the next study won’t take another year. The WHO director-general, Tedros Adhanom Ghebreyesus, might agree. He wasn’t directly involved with the study, but noted how difficult it was for the team to procure data — and their limited access to the Wuhan Institute of Virology.

Amy Maxmen, Nature senior reporter

Reference: Joint Statement on the WHO-Convened COVID-19 Origins Study

Pfizer–BioNTech vaccine works in teens

Pharmaceutical giant Pfizer and German biotechnology company BioNTech say their coronavirus vaccine is highly effective in adolescents. A clinical trial found, among 2,260 children 12 to 15 years old, no symptomatic infections and no serious side effects. There were 18 cases of COVID-19 in the placebo group. The data have not yet been published or peer reviewed. The companies plan to submit the data to regulators to extend emergency use approval for the jab, “with the hope of starting to vaccinate this age group before the start of the next school year”.

The New York Times | 6 min read

Reference: Pfizer and BioNTech press release

Features & opinion

AI spots cell structures that humans can’t

Researchers have harnessed deep learning to do ‘virtual staining’ — detecting many structures in a cell on the fly, without fluorescent labels. The artificial intelligence (AI) approach is trained on data from cells that have been fluorescently labelled. The AI can then pick out patterns in unlabelled images without making the sacrifices demanded by fluorescence microscopy, such as damage to the cells.

Nature | 8 min read

Learn to be a great lab leader

It’s never too early or late to start working on your leadership skills. The key to success is learning to form strong connections, a feat that might require a new way of thinking. “Scientists need a lot of self-sufficiency and determination,” says Kate Jennings, who trains science leaders. “But the things that helped drive you forward for your individual success don’t always play so well when you’re trying to bring out the best in other people.”

Nature | 9 min read

Quote of the day

“Some of the cuts we’ve been hearing about would be catastrophic, even existential.”

Nobel laureate Paul Nurse, the director of the Francis Crick Institute in London, responds to deep cuts made by the United Kingdom's main science funder to grants connected to foreign aid. (The Guardian | 3 min read)