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A polar bear stands on a sheet of ice

A polar bear near the coast of Spitsbergen, Svalbard Islands, Norway.SuperStock/Alamy

Polar bears risk extinction within 80 years

Nearly all polar-bear populations will be wiped out by 2100 unless we reverse the trend of sea-ice loss. “There is very little chance that polar bears would persist anywhere in the world, except perhaps in the very high Arctic in one small subpopulation” if we continue fuelling climate change with business-as-usual levels of emissions, says climate scientist Peter Molnar. Molnar and his colleagues analysed how long polar bears can survive and raise cubs during the ever-longer periods when parts of the Arctic are free of ice. Projections show that, if present rates of warming continue, the bears will starve between winters.

The New York Times | 5 min read

Reference: Nature Climate Change paper

US geoscience drops controversial test

Geoscience graduate programmes across the United States have joined other disciplines in dropping a controversial standardized test from their admissions requirements. The graduate record examinations (GRE), which was introduced in 1949, aims to measure verbal and quantitative reasoning, analytical writing and critical thinking. Academic researchers and others have criticized the test, claiming that it unfairly weeds out capable students and restricts the flow of women and people in minority ethnic groups into the sciences.

Nature | 4 min read

1%

The proportion of a condor’s flight time in which it flaps its wings. (Smithsonian Magazine | 4 min read)

Reference: PNAS paper

COVID-19 coronavirus update

A scientist working at the Oxford Vaccine Group's laboratory facility in Oxford

Steve Parsons/AFP via Getty

Three COVID-19 vaccines show promise

Three new vaccines produce an immune response to the new coronavirus. Two of the vaccines — one from China’s CanSino Biologics and the other from a collaboration between Oxford University and Astrazeneca — use an altered adenovirus that mimics the coronavirus and, when injected in humans, triggers the creation of antibodies against it. The third, from Pfizer and German biotech BioNTech, relies on messenger RNA (mRNA) that synthesizes a crucial part of the coronavirus called the receptor-binding domain. They join US biotechnology company Moderna, which last week published evidence that its mRNA-based vaccine provoked immune responses in its early-stage trial. Next comes the all-important large phase III trials that will show whether these vaccines actually protect people from the new coronavirus. “What this means is that each of these vaccines is worth taking all the way through to a phase III study,” said vaccine researcher Peter Jay Hotez. “That is it. All it means is ‘worth pursuing’.”

New York Times | 6 min read

Reference: The Lancet paper 1, The Lancet paper 2 & medRxiv preprint (not yet peer reviewed)

Duplication detector trawls preprints

Daniel Acuna, a computer scientist who develops automated programs to spot duplicate images in research papers, has applied his system to 3,500 COVID-19 preprints from the bioRxiv and medRxiv servers. In 4 hours, Acuna says, the software picked up around 400 instances of potentially duplicated images. Most turned out not to be problematic, says Acuna, but he selected 24 papers that he publicly flagged as having “interesting” duplicate images. The move raised some eyebrows, with Acuna and other scientists emphasizing that the software’s finds always need to be reviewed by a human.

Nature | 5 min read

Hints of hope for nebulizer treatment

An inhaled treatment for COVID-19 cut the risk of severe disease — such as that resulting in the need of a ventilator — by 79% in a small preliminary trial of people hospitalized in the United Kingdom. The treatment involves inhaling a protein called interferon beta, which is naturally produced to fight off infection, directly into the lungs. UK biotech company Synairgen has not yet released the results in full for peer review.

BBC | 6 min read

Reference: Synairgen webinar

Notable quotable

“Humanity’s history is a continuous battle between us and the microbes. For most of our history we were on the losing side.”

Economist Max Roser explores how vaccines, antibiotics and sanitation helped to cut child deaths by tenfold in the last century — and why our best hope against the coronavirus is science. (Our World in Data blog | 9 min read)

Features & opinion

Build your network without conferences

“When I became an associate professor at a relatively unknown university in China last year, I knew the odds were against me in the networking game. I felt I would be invited to fewer conferences and have less appeal as a networking prospect at those I did attend,” says Edmond Sanganyado, who researches environmental organic chemistry and climate change. He shares how alternative networking strategies including AuthorAID, LinkedIn and WeChat, can help to plug the connections gap.

Nature | 6 min read

How to write the perfect recommendation

Undergraduates need them for graduate-school applications; PhD students and postdocs use them to apply for fellowships and jobs; senior scientists often have to have them to apply for awards and promotions. But writing an effective and personal recommendation letter can be time-consuming — and some might struggle to know what to say. Nature spoke to three experienced professors to get their tips for writing the perfect recommendation letter.

Nature | 5 min read

Image of the week

Image of the Royal Mint's Rosalind Franklin 100th anniversary coin reverse

The UK Royal Mint has released this 50-pence coin in honour of the hundredth anniversary of biophysicist Rosalind Franklin’s birth on 25 July. It features a stylized version of her X-ray crystallography image of DNA, which contributed to the discovery of the molecule’s double-helix structure. It’s “the world's most important photograph”, says Ed Byrne, the president and principal of King’s College London, where Franklin captured the image. “This coin represents the broader societal recognition she so richly deserves.” Franklin died aged 37, in 1958, from cancer. (King’s College London press release | 3 min read)

Quote of the day

“She didn’t ask me, ‘Are you somebody’s student?’ It just went straight to, ‘I’m gonna call the police.’”

Science communicator Raven Baxter shares the story of an encounter with a white co-worker on her first day as an assistant professor of biology. (Mother Jones | 13 min read)