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An illustration of human brain nerve cells pictured in blue

Neurons (artist’s illustration) that affect hunger lose their ability to sense insulin when encased by a sticky scaffolding.Credit: KTSDesign/SPL

‘Brain goo’ might drive obesity

A buildup of ‘goo’ in an appetite-control centre of the brain might worsen obesity and diabetes. In mice, researchers found that the scaffolding supporting neurons that adjust sensations of hunger changed as the mice gained weight on an unhealthy diet. The result was a thick and sticky goo that prevents these neurons from processing insulin signals. When the scientists chemically slowed the goo’s formation, the mice lost weight and became more responsive to insulin. The findings may point to new drivers of metabolic conditions, but investigating whether this goo forms in humans might be difficult, says neuroscientist and co-author Garron Dodd.

Nature | 4 min read

Reference: Nature paper

China about to reach peak emissions

China’s greenhouse-gas emissions could be about to peak, if they haven’t already. The peak would be a major climate milestone, and comes well ahead of Beijing’s pledge of peak emissions before 2030. But some researchers are uncertain about the accuracy of current peak predictions and worry that China’s road to net zero afterwards will be a challenge. Nevertheless, China’s decarbonization “could offer valuable lessons for other developing nations striving to decouple economic growth from their emissions”, says climate economist Sun Yongping.

Nature | 5 min read

Entangled quarks seen for first time

For the first time, scientists have observed quantum entanglement — a state in which particles intermingle and can’t be described separately — in fundamental particles called top quarks. Physicists had no reason to suspect that quarks wouldn’t allow themselves to be entangled, but researchers say this measurement, achieved by analysing over 1 million pairs of quarks created in collisions between protons, could pave the way for future high-energy tests of the phenomenon. “You don’t really expect to break quantum mechanics, right?”, says theoretical physicist Juan Aguilar-Saavedra. “Having an expected result must not prevent you from measuring things that are important.”

Nature | 6 min read

Reference: Nature paper

An infographic of the products formed during proton collision. Protons break up into quarks and gluons.

When two protons collide at high velocity, they break up into elementary particles known as quarks and gluons. If two gluons then collide, they can fuse, creating a top quark and its antiparticle, an anti-top quark. This pair decays into a bottom quark, an anti-bottom quark and two elementary particles known as W bosons. The W bosons subsequently decay into particle–neutrino pairs comprising, for instance, an electron and an anti-neutrino or an anti-muon and a muon neutrino. (Nature News & Views | 6 min read, Nature paywall)

Features & opinion

How cells swap instant messages

Cells in our bodies are passing delicate, time-sensitive notes to each other. These notes come in the form of messenger RNA (mRNA), which cells have to neatly package in sacs called vesicles to send between cells. This year, researchers showed that cells in all three domains of life - archaea, bacteria and eukaryotes - can send these messages, and even that they can be used as weapons between species. There are still questions to answer, such as whether other molecules packed into vesicles are necessary for mRNA’s message to land, but “it’s a fun challenge to unravel all of that”, says biologist Amy Buck. “I’ve been in awe of what RNA can do.”

Quanta Magazine | 9 min read

The ethics of brain-computer links

Technologies that allow brain-computer interfacing could be revolutionary for individuals with severe disabilities, but they raise ethical challenges. Whether they’ll develop into highly personalized treatments or become standardized and widely available has implications on their equity, and managing public expectations of the reality of these interfaces compared to their depictions in media is vital to avoid false hope and miscommunication. As this tech moves out of the lab and into the real world, medical ethicists Anna Wexler and Ashley Feinsinger explore how their therapeutic benefit can be realized as responsibly as possible.

Nature Human Behaviour | 8 min read

Science policy is no snoozefest

Crafting science policies is important and rewarding work, say four science-policy specialists interviewed by Nature. Their jobs involve briefing global leaders on breakthrough technologies, presenting the White House’s climate agenda to the press and helping emerging economies to reduce carbon emissions without compromising their development. Getting on policymakers’ radar and building trust with government officials can be a challenge, but in a world reeling from a pandemic and grappling with climate change, science-policy advisers are needed now more than ever.

Nature | 10 min read

Your end-of-year traditions

Here at Nature, we’re wondering how you mark the end of a hard year’s work. Do you celebrate and show gratitude for your colleagues or have any special end-of-year traditions in the lab? Nature’s careers team is writing about researchers’ seasonal traditions, parties and gift-giving. If you’d be willing to be interviewed for the piece, let us know at briefing@nature.com

QUOTE OF THE DAY

“It felt like a sort of botanical love story, harbouring the hope that a female might still be out there.”

Biological artist Laura Cinti is using artificial intelligence to hunt for an elusive female specimen of what she calls ‘the world’s loneliest plant’, the tree Encephalartos woodii. Most in existence are clones of one wild, male specimen found in 1895, leaving them vulnerable to disease. If she can find a female, the trees can pollinate and reproduce. (The Conversation podcast | 20 min listen)