Volume 579 Issue 7800, 26 March 2020

The international community underestimated the volume of chlorofluorocarbons locked up in old cooling units. They must be disposed of safely.

Private companies get free access to data that are more informative than what researchers are forced to compete for.

A little flying robot can nimbly dart out of the path of an incoming ball.

Shock waves might explain the flow of wine droplets after a glass is swirled.

Prehistoric people collected more than 60 mammoth skulls to build a ring-shaped edifice in what is now Russia.

When heated, an ingredient in some e-cigarette mixtures is transformed into a dangerous gas.

Modelling finally explains how debris from a space rock’s impact travelled around the world.

Ordinary lighting can activate a compound that attacks bacteria lurking on hospital surfaces.

Dozens of polio outbreaks in the past few years have been linked to a polio vaccine that many nations abandoned in 2016.

The latest science news, in brief.

Researchers are studying the effects of China’s lockdowns to glean insights about controlling the viral pandemic.

US authorities are failing to test people and notify their contacts, a cornerstone of outbreak response.

Some experts warn that accelerated testing will involve some risky trade-offs.

From papers published to carbon emissions to confirmed cases, these data reveal an unprecedented viral outbreak and its impacts around the world.

As geopolitical tensions rise in nuclear-armed states, scientists are modelling the global impact of nuclear war.

Two manifestos call for climate action on different scales — national and global. By Maria Ivanova.

Andrew Robinson reviews five of the week’s best science picks.

Radioactive fails to get under the physicist’s skin. By Georgina Ferry

Neuroscientist who pioneered studies of the brain’s memory circuits.

Many people now have two or more diseases at once. It is time to rethink funding, research, publishing, training and treatment for this growing problem.

Men outnumber and out-earn women, and white people take up more posts and are more likely to be in the highest pay grades than people from minority ethnic groups.

A few modest adjustments to the planning and delivery of talks can help scientists share ideas with their peers more effectively, say Scott St. George and Michael White.

A by-product of alcohol metabolism can damage the genome by crosslinking opposing DNA strands. The discovery of a safe mechanism that reverses such damage might open up avenues of research for drug discovery.

The Antarctic ozone hole shifted the jet stream in the Southern Hemisphere poleward, leading to hemisphere-wide climatic changes. But the Montreal Protocol, which banned ozone-depleting substances, has halted the shift.

Analysis of nucleic-acid sequences from human cancers, along with samples from adjacent tissue and blood, reveals the presence of microorganisms in tumours and blood across cancers.

Chromatin, the complex of DNA and protein in cell nuclei, can be modified by ubiquitin molecules. It emerges that this modification occurs in a molecular reaction chamber formed from an enzyme and a scaffold protein.

In 1980, a method was found to determine the amount of carbon dioxide in ancient air trapped in polar ice — providing direct evidence that CO₂ is coupled to climate, and affects global temperatures in the past, present and future.

Thermal imaging data obtained from the spacecraft Hayabusa2 reveal that the carbonaceous asteroid 162173 Ryugu is an object of unusually high porosity.

Scanning tunnelling microscopy and spectroscopy measurements show chiral edge states inside the superconducting gap of the heavy-fermion superconductor UTe₂, indicating the presence of chiral spin-triplet superconductivity.

A quantum dot device designed to host four electrons is used to demonstrate Nagaoka ferromagnetism—a model of itinerant magnetism that has so far been limited to theoretical investigation.

An on-chip, all-electronic device based on the formation of a nanoplasma provides ultrafast electron transfer, enabling picosecond switching of electric signals and the generation of high-power terahertz pulses.

Cryo-STEM tomography of ferritin crystallization is used to reveal nonclassical evolution of crystalline order, indicating that it may be desolvation that drives the continuous evolution of order in crystallization.

The recovery of stratospheric ozone in the Southern Hemisphere in the wake of the Montreal Protocol is driving a pause in atmospheric circulation trends that warrants closer scrutiny across the Earth system.

The pectoral fin of an Elpistostege watsoni specimen from the Upper Devonian period of Canada combines digits and fin rays, blurring the line between the appendages of fish and land vertebrates.

Detection of dopamine dips by neurons that express dopamine D2 receptors in the striatum is used to refine generalized reward conditioning mediated by dopamine D1 receptors.

FERONIA prevents polyspermy in Arabidopsis by enabling pectin-stimulated nitric oxide accumulation at the filiform apparatus after the first pollen tube arrives, which disengages LURE1 chemoattraction to prevent late-arriving pollen tubes from entering the ovule.

Microbial nucleic acids are detected in samples of tissues and blood from more than 10,000 patients with cancer, and machine learning is used to show that these can be used to discriminate between and among different types of cancer, suggesting a new microbiome-based diagnostic approach.

Feeding controls a neuroimmune circuit comprising VIP-producing neurons and type-3 innate lymphoid cells that helps to regulate the efficiency of nutrient uptake and IL-22-mediated immune protection in the intestine.

Visceral adipose tissue contains populations of regulatory T cells that exhibit sexual dimorphism, determined by the surrounding niche, and differ between male and female mice in terms of cell number, phenotype, transcriptional landscape and chromatin accessibility.

A genetic mouse model is used to reveal a two-pronged mechanism of fructose-induced de novo lipogenesis in the liver, in which fructose catabolism in hepatocytes provides a signal to promote lipogenesis, whereas fructose metabolism by the gut microbiota provides acetate as a substrate to feed lipogenesis.

The yeast E3 ligase Bre1 forms a core–shell condensate with the scaffold protein Lge1, implicating liquid–liquid phase separation as a mechanism in the ubiquitination of histone H2B along gene bodies.

Assembly of a catalytic centre formed by HPF1 bound to PARP1 or PARP2 is essential for protein ADP-ribosylation after DNA damage in human cells.

DNA interstrand crosslinks induced by acetaldehyde are repaired by both the Fanconi anaemia pathway and by a second, excision-independent repair mechanism.

A computational screen of an ultra-large virtual library against the structure of the melatonin receptor found nanomolar ligands, and ultimately two selective MT₁ inverse agonists that induced phase advancement of the mouse circadian clock when given at subjective dusk.

The authors provide high-resolution structures of two arenavirus polymerases, revealing that the active site of arenavirus polymerase is inherently switched on, without the requirement for allosteric activation by 5′-viral RNA, and that dimerization facilitates polymerase activity.