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Alastair Fyfe

Graffiti turns cities into botanical tours

Ephemeral labels are springing up on the plucky plants that inhabit urban streets. ‘Rebel botanists’ are chalking names near weeds and trees to strengthen people’s connection to nature and raise awareness of overlooked flora. The trend first exploded in France and has now taken root in other countries — including the United Kingdom, despite it being illegal to chalk anything on public land. “Botanical chalking gives a quick blast of nature connection, as the words encourage you to look up and notice the tree above you, the leaves, the bark, the insects, the sky,” says one anonymous chalker in London. “And that’s all good for mental health.”

The Guardian | 7 min read

Lengthy experiment reveals origins of dirt

A two-and-a-half-year experiment has found evidence that bacteria make dirt. Scientists have long believed that microorganisms are involved in turning rock into soil — the mix of solid, gaseous and liquid matter, part mineral and part organic, that supports most land ecosystems. But the process tends to happen too slowly to be observed in a lab. Researchers started with an exceptionally fast-weathering rock called quartz diorite and ground it to speed things up even more. After 30 months, samples that had been kept sterile retained sharp, smooth edges, whereas those that had been exposed to bacteria looked ragged and pitted. They also contained abundant ATP, a chemical generated by feasting microbes.

Scientific American blog | 5 min read

Reference: PNAS paper

COVID-19 coronavirus outbreak

Convalescent serum treatment on the rise

Treating people with the antibody-laden blood of those who have already survived an infection is a century-old approach to battling viruses. Evidence for its efficacy against COVID-19 is thin on the ground, but it has two big advantages over new treatments: it’s available now and it’s relatively safe, as long as the blood is screened. In the United States and the United Kingdom, major efforts have begun to spur plasma donations from survivors. And large pharma companies are joining forces to develop antibody products purified from the pooled plasma of donors, or produced in genetically modified cattle.

Nature Biotechnology | 10 min read

Read more: How blood from coronavirus survivors might save lives (Nature, from March)

Podcast: Contact-tracing apps and remdesivir

Get the expert view from Nature’s news team in our weekly audio overview of the state of coronavirus science. This week, we dig into the promise of contact-tracing apps, early results from a US trial of the antiviral drug remdesivir and things that have made us smile in the past week.

Nature Coronapod | 32 min listen

Protecting apes from COVID-19

The coronavirus can probably infect great apes — putting endangered animals in Africa and Asia at risk. Tourism in African parks has been stopped, and researchers who observe chimpanzees in Uganda and Côte d’Ivoire are taking extra precautions, such as wearing masks and changing their clothes, to prevent animal infections. If these measures fail and apes get too sick to defend themselves from leopards and poachers, researchers plan to sleep nearby to protect them. On the Indonesian island of Sumatra, an orangutan-conservation programme has moved some of the island’s orangutans to another site to reduce the risk to the whole population.

Science | 6 mins

“We may lose a whole generation of researchers”

Researchers forced to prematurely halt their experiments are facing grief and uncertainty over what comes next. Early-career researchers, senior scientists and a researcher who bid a final farewell to a mentor share their experiences. “In the end, I found myself euthanizing mice by the masses in the university basement,” says neuroscientist Kathleen Beeson, who grieves for her hand-reared colony of experimental animals and her interrupted research. “It was the punctuation on a sad and disorienting week.”

STAT | 8 min read

Notable quotable

“Our healthcare providers should be able to count on the healthcare systems in which they work to protect their mental health as well as their medical health.”

Stress is the hidden pandemic for health-care workers, argues psychiatrist John Krystal. (Nature Medicine | 4 min read)

Coronavirus research highlights: 1-minute reads

Young children are not immune to COVID-19

Children are as likely as adults to contract SARS-CoV-2 after close contact with an infected person, according to a study in Shenzhen, China. Researchers analysed nearly 400 cases of COVID-19 and 1,300 people who were ‘close contacts’ of the infected people. Seven per cent of close contacts younger than age 10 became infected — roughly the same as in the population overall. The researchers also found that just 9% of original cases — the ‘superspreaders’ — were responsible for 80% of infections detected in close contacts.

Reference: The Lancet Infectious Diseases paper

SARS-CoV-2 might hijack its host’s immune defences

The new coronavirus invades human cells after one of its proteins binds with ACE2, a protein found in cells in many human organs. Researchers studied airway cells from people with influenza (influenza virus also invades the respiratory tract), and found that signalling molecules called interferons — which normally fend off viruses — switch on the host genes encoding the ACE2 protein. The result suggests that the body’s defences against viral attack drive the activation of the gene for ACE2.

Reference: Cell paper

Immune system shows abnormal response to COVID-19

The immune response to SARS-CoV-2 differs from the response prompted by other respiratory viruses, according to an analysis of infected cells, ferrets and humans. The results suggest an immune imbalance: low levels of interferons reduce a cell’s ability to limit viral replication, and the activation of less-specific immune responses promotes inflammation.

Reference: Cell paper

Get more of Nature’s continuously updated selection of the must-read papers and preprints on COVID-19.

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Quote of the day

“His ideas are still many moves ahead.”

Theoretical physicist Piers Coleman remembers Philip Anderson, one of the most influential theoretical physicists of the twentieth century, who died on 29 March, aged 96. (Nature | 5 min read)