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The collision of two black holes holes is seen in this still from a computer simulation.

LIGO can detect gravitational waves that are generated when two black holes collide.Credit: The SXS Project

LIGO is back, and better than ever

The Laser Interferometer Gravitational-Wave Observatory (LIGO) is back after a three-year hiatus and a multimillion-dollar upgrade. The first detection of gravitational waves — ripples in space–time from colliding black holes and other cosmic cataclysms — was made at LIGO in 2015. Improvements to the detectors’ sensitivity mean that LIGO could pick up signals of colliding black holes every few days, compared with once a week during its previous run. Scientists hope to detect the gravitational signal of a collapsing star before it manifests as a supernova explosion, as well as the continuous gravitational waves produced by a pulsar.

Nature | 6 min read

‘Digital bridge’ allows paralysed man to walk

A wireless connection between the brain and the spinal cord allows a paralysed man to walk using his thoughts. Gert-Jan Oskam, whose legs were paralysed after a cycling accident, received a spinal implant in 2018 that generated robotic movement through pre-programmed electrical stimulation. He has now received head implants that detect brain activity and transmit the signal to a backpack computer, which decodes the information and activates the spinal pulse generator. This brain–spine interface gives Oskam full control over the stimulation, so he can walk and climb stairs. “The stimulation before was controlling me and now I am controlling stimulation by my thought,” he says.

Nature | 4 min read

Reference: Nature paper

Baby mice hearts mature with mother's milk

A component in their mother’s milk triggers a diet switch in baby mice’s heart cells. Mouse embryos’ heart-muscle cells burn sugar and lactic acid, but within 24 hours of birth, they shift to fatty acids as their fuel. After seven years of experiments, some of which involved milking mice by hand, researchers now zeroed in on ɣ-linolenic acid as a key compound that drives the switch, and identified the receptor and genes involved. Human breast milk also contains ɣ-linolenic acid, and a precursor is found in baby formula, although it’s unclear whether it has the same role in humans.

Nature | 4 min read

Go deeper with an analysis by heart development experts in the Nature News & Views article (6 min read, Nature paywall)

Reference: Nature paper

China’s data privacy laws deter researchers

China’s new data restrictions have strengthened privacy but are concerning researchers globally. “The signal has been very clear that China does not want its scientists to collaborate as freely as they used to with foreigners,” says sociologist Joy Zhang. China’s largest academic database has partially suspended foreign access, and institutions that send, for example, clinical-trial data abroad must now undergo a security assessment. Unlike the European Union’s data protection regulation, the law has no exemption for scientists. The Chinese government has also proposed adding CRISPR gene editing, crop breeding and photovoltaics techniques to its list of technologies whose export is prohibited or restricted.

Nature | 7 min read

Japan wants to privatize its science council

Japan’s government is drawing fresh ire from researchers over plans to privatize the country’s influential science council (SCJ). The government has already backed away from plans to reform the council’s constitution and its process for appointing members. Observers predict that the council will ultimately be forced to forge a new relationship with the government: “I think the SCJ will have to find a way of existing as an organ within the government, while being independent,” says policy researcher Hiroshi Nagano.

Nature | 5 min read

Features & opinion

Quantum computers: terrible and awesome

Even the scientists who have made quantum computers their life’s work say they can’t do anything useful — yet. “They’re all terrible,” says physicist Winfried Hensinger of the five he owns (he’s working on a new large-scale, modular type). But enthusiasts aren’t concerned — and researchers say development is proceeding better than expected. The devices have the potential to accelerate drug discovery, crack encryption, speed up decision-making in financial transactions, improve machine learning, develop revolutionary materials and even address climate change — and that barely scratches the surface, researchers say. “The short-term hype is a bit high,” says computational mathematician Steve Brierley, a founder of a quantum-computing firm. “But the long-term hype is nowhere near enough.”

Nature | 10 min read

Swap debt for science in Africa

Across Africa, 43% of people still do not have electricity — and one of the causes is that highly indebted countries can’t invest in research. Many countries find it impossible to pay off debts and protect public spending, which excludes them from expanding their scientific capabilities. Creditors should consider a ‘debt-for-science swap’, argues a Nature editorial: agree to waive some debt for countries that spend more on research.

Nature | 5 min read

Quote of the day

“At the root of the problem is the mismatch between the idea of a university as a refuge for lone geniuses and the collaborative nature of contemporary science.”

The research system still tends to put power in the hands of just a handful of people. Universities should look to industry to learn how to better reflect how research is done today, argues a Nature editorial. (5 min read)