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Tonga eruption offers insights on Mars

NASA scientists say the eruption of a submarine volcano in Tonga is helping them to understand how features formed on the surfaces of Mars and Venus. The unusual explosion offers a chance to study how water and lava interact. The volcanic island, which began to form in 2015, piqued the interest of researchers at NASA’s Goddard Space Flight Center, because of its similarity to structures on our planetary neighbours. Volcanic islands typically last for just months before being eroded away, but Hunga Tonga–Hunga Haʻapai survived for years, allowing them to use satellite observations and seafloor surveys to study how such islands form, erode and persist.

Nature | 6 min read

NBA teams offer Omicron insights

Evidence from National Basketball Association (NBA) players and staff suggests that the swift spread of the Omicron coronavirus variant is not because it causes a high viral load. Researchers analysed the treasure trove of COVID-19 tests collected as part of the league’s strict health and safety protocols. For people infected with Delta, the peak level of virus was similar to or slightly higher than that of those with Omicron. The results suggest that Omicron’s hyper-transmissibility does not stem from the release of large amounts of virus from infected people. Instead, the best explanation for its lightning-fast spread is its ability to evade SARS-CoV-2 immunity caused by either vaccination or past infection.

The NBA study, and a separate study in Switzerland, also suggest that five days of isolation might not be enough to stop the spread. In people with breakthrough Delta infections, about half of the Swiss samples still held infectious virus five days after the individuals tested positive. Five days after an initial positive test for Omicron, about half of tested NBA personnel had viral loads high enough that they were probably still infectious.

Nature | 4 min read

Reference: medRxiv preprint 1 & medRxiv preprint 2 (not peer reviewed)

The science behind the anti-ageing boom

Yesterday, an ageing-research initiative called Altos Labs was launched with US$3 billion in initial financing from backers including world’s richest person Jeff Bezos. It’s the latest in a surge of anti-ageing ventures that rely on ‘partial reprogramming’ using Yamanaka factors — four transcription factors that can reprogram cells into an embryonic-like state that can give rise to different cell types. Studies in rodents and in cultured mammalian cells have shown that partial reprogramming can dramatically reverse some signs of ageing. But it’s still a mystery what processes underlie this rejuvenation. And there are risks: reprogrammed cells readily form tumours known as teratomas, and some Yamanaka factors have been linked to cancer.

Nature Biotechnology | 9 min read

Read more: Ageing — the mysteries of human longevity (Nature Outlook | 9 features plus relevant research papers)

Do mental-health apps actually work?

Studies of smartphone apps for mental health are not rigorous enough to show whether the apps are effective compared with other treatments. Researchers examined 14 meta-analyses of 145 randomized control trials for mental-health interventions, including treatments for depression, anxiety and smoking cessation. They found that none of the trials showed “convincing evidence” that the mobile-phone-based interventions had any effect, because of shortcomings in the study designs. There was “highly suggestive” evidence that eight of the interventions were more effective than controls that provided no treatment at all — which still might be valuable, given that apps are vastly cheaper and more widely accessible than face-to-face interventions.

STAT | 4 min read

Reference: PLOS Digital Health paper

Features & opinion

Pandemic preprints changed science forever

The pandemic unleashed a staggering tide of preprint studies, which are released publicly before they have been peer reviewed. The stakes had never been higher, swift action was crucial and pre-printing results aided rapid data sharing, which expedited research. But it exposed the inner workings of the scientific process to a new audience and laid bare the best and worst of pandemic research. “We are down a pathway of open science, and that pathway is going to accelerate,” says physician-scientist Kyle Sheldrick. “Our choice is not whether it occurs or not; our choice is whether it occurs responsibly.”

Nature Medicine | 12 min read

Read more: How COVID broke the evidence pipeline (Nature | 14 min read, from May)

Tiny beetle reveals new way to fly

Flying is a tricky business, but when you are less than a millimetre long, things get even tougher. At such tiny scales, the physics of flight changes, so insects have evolved strategies to fly in miniature. Watch the never-before-seen flight tactics of a species of feather wing beetle.

Nature | 3 min video

Reference: Nature paper