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brain organoid

A slice through a brain organoid shows more mature cortical neurons on the outer edge of the structure.Credit: Muotri Lab/UC San Diego

Lab-grown brains produce human-like waves

Blobs of brain tissue grown in a dish have spontaneously produced human-like brain waves for the first time — and the patterns look similar to those seen in premature babies. The ‘organoids’ aren’t real brains: they don’t contain all the cell types in a real cortex and they lack any connections to other brain regions. Nevertheless, the advance could eventually help scientists to overcome the practical and ethical difficulties of studying real fetal brains. But the organoids raise their own ethical dilemmas. “The closer they get to the preterm infant, the more they should worry,” says neuroscientist Christof Koch.

Nature | 3 min read

“Le grand K” is dead. Long live the defined kilogram

No longer is the kilogram defined as the mass of a 129-year-old platinum–iridium cylinder in a vault in Paris. Representatives of 60 countries at the General Conference on Weights and Measures have voted unanimously to redefine the kilogram in terms of the Planck constant (where the Planck constant is 6.62607015 × 10−34 kg m2 s-1, to be exact). The change frees scientists from any particular reference object, meaning they can now independently measure the mass of anything — assuming they have a handy way to stack it up against the Planck constant. The ampere, the kelvin and the mole will also be redefined based on their relationships to the charge on the electron, Boltzmann’s constant and Avogadro’s number, respectively.

Nature | 7 min read

TL;DR: Nature reporter Elizabeth Gibney is at the conference and tells all in one Twitter thread along with this fantastic selfie.

Early-warning system predicts volcano eruptions

The world’s first automated volcano early-warning system can alert authorities roughly one hour before an eruption of Mount Etna, Europe’s largest active volcano. The approach detects low-frequency infrasound waves that Etna produces before erupting. When tested, the system successfully predicted 57 out of 59 eruptions over 8 years. It now sends automatic emails and text messages to Italian authorities.

Nature | 4 min read

Reference: Journal of Geophysical Research:Solid Earth paper

Gene-drive ban is back on the table

Government representatives from nearly 170 countries will this month consider a temporary moratorium on the release of organisms carrying gene drives — a controversial technology that can quickly propagate a chosen gene throughout a population. A ruling is unlikely, because all 170 countries at the United Nations Convention on Biological Diversity must agree — but some scientists worry that the discussions could set the tone for a future ban. Gene drives are under development for everything from stopping malaria-transmitting mosquitoes to controlling invasive rodents in island ecosystems.

Nature | 6 min read

Ancient Celts took heads as trophies

A cache of human bones confirms historical accounts that the ancient Celts decapitated their enemies and embalmed the heads with cedar oil for public display. Skull fragments from southern France showed evidence of oil residue and tell-tale cut marks.

Nature Research Highlights | 1 min read

Reference: Journal of Archaeological Science paper

Get more of Nature’s Research Highlights: short picks from the latest papers.

BOOKS & ARTS

Daphne Oram smiles in her Kent studio surrounded by tape machines, mixers and electronic equipment.

Daphne Oram in her home studio in 1962.Credit: Daily Herald Archive/NSMM/SSPL/Getty

Female pioneers of electronic music

A series of new performances celebrates The BBC Radiophonic Workshop, one of the birthplaces of electronic music. Many of the workshop’s engineers were women, who spun wartime skills and the memories of air-raid sirens into the iconic sounds of the original Doctor Who and The Hitchhiker’s Guide to the Galaxy.

Nature | 6 min read

Five best science books this week

Barbara Kiser’s pick of the top five science books to read this week includes ethics at the cutting edge, beastly movers and shakers, and teeth as time machines.

Nature | 3 min read

Figure 1 | A planet around Barnard’s star. Ribas et al.1 report evidence that a low-mass planet orbits a nearby star called Barnard’s star. Shown here is the orbital distance of the planet, compared with those of the four inner planets of the Solar System. The distances are given in astronomical units (1 au is the average separation between Earth and the Sun). The discovered planet is on a relatively wide orbit. The sizes of all the objects are approximately to scale.

SCIENTIFIC LIFE

How to make undergraduate research worthwhile

“How do we avoid wasting our time as mentors and our students’ time as learners and researchers?” asks neurobiologist Shaun Khoo. He suggests pinning down long-term goals, facing up to the opportunity cost, focusing on transferable skills and reflecting on how to create a win–win situation.

Nature | 5 min read

Paying PIs from grants blocks talent and diversity

Paying principal investigators’ (PIs) salaries from the direct costs covered by their research grants leads to a vicious cycle of hiring and applying, argue three biomedical researchers in a letter to Nature. Government institutions pay the salaries and benefits of teachers and firefighters — research centres should do the same for PIs, they say.

Nature | 2 min read

Closeup of a mango-seed weevil face with feather-like skin.

This larger-than-life portrait of a mango-seed weevil (Sternochetus mangiferae), taken by Pia Scanlon, placed eighth in Nikon’s 2018 Photomicrography Competition.

See more of our picture editors’ picks for best science photos of the month.