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The University of Cape Town’s Jagger Library, has been gutted.

The gutted interior of the University of Cape Town library's Jagger Reading Room, which was built in the 1930s.Credit: Ashraf Hendricks/GroundUp

Fire damages historic South African library

Forest fires raging in South Africa’s Table Mountain National Park have reached the University of Cape Town and gutted the reading room of its main library, which houses irreplaceable documents and records from the country’s past. “We lose that texture of everyday life and struggles with a catastrophe like this,” says historian Sarah Emily Duff. The university’s botany building was also seriously damaged. Researchers have put out a call for anyone with photos or scans of the library’s collections to come forward to help recover some of the lost records. The “damage is total” says Timm Hoffman, a historical ecologist.

Nature | 4 min read

Research highlights: 1-minute reads

• The bright lights of Las Vegas, Nevada, drew a plague of grasshoppers to the city in 2019. Researchers found that pallid-winged grasshoppers (Trimerotropis pallidipennis) moved from vegetated areas to highly lit urban areas as night fell.

• A remote-sensing device can sketch objects 200 kilometres away, one photon at a time. The lidar system builds up a 3D image by bouncing a laser off the distant object. Its custom light sensor detects single photons with high efficiency and low noise.

• Small farms outdo big ones on biodiversity — and crop yields. Researchers analysed 118 studies conducted over 50 years across 51 countries to assess how farm size affects outcomes other than food production. Large-scale farms account for most of the global food supply, but the 84% of farms that are less than 2 hectares in size protect species and are just as profitable.

• The drop in a person’s blood-sugar levels a few hours after a meal predicts how much they’ll eat over the rest of the day, suggesting that hunger can be quantified. Researchers followed the eating habits of 1,070 healthy adults in the United Kingdom and United States for 2 weeks. Participants wore blood sugar and activity sensors, and logged their meals and hunger levels in a mobile-phone app.

COVID-19 coronavirus update

The long road to healing long COVID

Nearly one-third of people who are hospitalized with COVID-19 are readmitted to hospital within months — that’s 4 times the rate in the control group of a study of nearly 48,000 people in the United Kingdom. “Hospitalized patients who have survived hospital discharge think, ‘Woohoo, I'm through the worst of it.’ But actually, that's not the end of the story by a long shot,” says intensive-care specialist Charlotte Summers. Summers is leading a British trial starting this month, HEAL-COVID, to study treatments that could reduce the long-term effects of SARS-CoV-2 infection. Other trials are launching elsewhere, including a US$1-billion US National Institutes of Health (NIH) study of ‘post-acute sequelae of SARS-CoV-2 infection’. The first hurdle: how to design a trial that can analyse a condition we still barely understand.

Nature Reviews Drug Discovery | 11 min read

Read more: US health agency will invest $1 billion to investigate ‘long COVID’ (Nature | 5 min read, from March)

Reference: BMJ paper

Blood clots: the theories

What might be the mechanisms that possibly underlie the very rare blood clots that have been linked with the Johnson & Johnson and Oxford–AstraZeneca COVID-19 vaccines? Early evidence suggests that a platelet problem might be in play, or it could be something related to the adenovirus technology in use in both jabs. The answers are key to ensuring the safety of these life-saving vaccines — and could point the way to what causes dangerous clotting in people who get COVID-19.

The Atlantic | 10 min read

Notable quotable

Image of the week

Virus hunters in the Philippines.

Credit: Eloisa Lopez/Reuters

Ecologists Phillip Alviola and Edison Cosico wait beside a net that they set up near a bat roost at Mount Makiling in Los Banos, in the Laguna province of the Philippines. The work is part a project that aims to help avert potential pandemics by identifying bat coronaviruses. The researchers wear protective hazmat suits, in case any bats they handle already carry diseases that can infect people. They hope to catch thousands of bats over the next three years, and will take oral swabs that can be analysed for viral material. “What we’re trying to look into are other strains of coronavirus that have the potential to jump to humans,” says Alviola. “If we know the virus itself and we know where it came from, we know how to isolate that virus geographically.”

See more of the month’s sharpest science shots, selected by Nature’s photo team. (Nature | Leisurely scroll)