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Scientists Waited Two and a Half Years to See whether Bacteria Can Eat Rock

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https://blogs.scientificamerican.com/artful-amoeba/scientists-waited-two-and-a-half-years-to-see-whether-bacteria-can-eat-rock/?utm_source=Nature+Briefing&utm_campaign=a015790705-briefing-dy-20200504&utm_medium=email&utm_term=0_c9dfd39373-a015790705-44992633
Scientists Waited Two and a Half Years to See whether Bacteria Can Eat Rock

Common Sense Comes to Computers | Quanta Magazine

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Common Sense Comes to Computers | Quanta Magazine



How to give a computer common sense

Computer scientists have built a system that can make simple guesses — for example, what happens after “Gary stacks kindling and logs and drops some matches”. Machine-learning techniques, such as neural networks, can make statistical guesses after absorbing large amounts of data, but they are notoriously lacking common sense. Other attempts relied on knowledge bases containing millions of rules and sentences handpicked by humans. COMET combines the two approaches, using a knowledge base to train a neural network. Lead researcher Yejin Choi says she was surprised that no one had tried this approach before. “It’s almost as if nobody bothered because they were so sure this would never work.” COMET’s guesses are still statistics-based, but at least they’re often right.
Quanta | 14 min read

One billion people will live in insufferable heat within 50 years – study | Environment | The Guardian

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One billion people will live in insufferable heat within 50 years – study | Environment | The Guardian

Elevated view of an Indian farmer crossing a dry pond bed.



An Indian farmer walks across the bed of a pond that has dried during a water crisis. (Sanjay Kanojia/AFP via Getty Images)

More than 1 billion face unbearable heat

Models of population growth and warming indicate that climate change is pushing much of humanity out of the comfortable ‘climate niche’ we have enjoyed for the past 6,000 years. If no substantial action is taken to cut greenhouse-gas emissions, places home to one-third of the global population will experience temperatures similar to the Sahara’s within 50 years. Even under optimistic scenarios, the homelands of more than 1 billion people will become unbearably hot by 2070 — with catastrophic consequences for human migration and food production. “I’ve previously studied climate tipping points, which are usually considered apocalyptic. But this hit home harder. This puts the threat in very human terms,” says climate scientist Tim Lenton.
The Guardian | 6 min readSource: PNAS paper

Closest black hole to Earth found 'hiding in plain sight'

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Closest black hole to Earth found 'hiding in plain sight'

This artist’s impression shows the orbits of the objects in the HR 6819 triple system.

This artist’s impression shows the orbits of the objects in the HR 6819 triple system. The system is made up of an inner star (orbit in blue) and a newly discovered black hole (orbit in red), as well as a third star in a wider orbit (also in blue). (ESO/L. Calçada)

The black hole next door

A black hole merely 1,011 light years from our solar system is the closest ever discovered. Astronomers uncovered its presence while studying the binary star system HR 6819 in the constellation Telescopium. The central star orbits a mysterious object every 40 days or so, and the outer star encircles the central star and the object, which has a mass of 4.2 suns. A regular star of that size would shine brightly — so a black hole is the only option. “It seems like it’s been hiding in plain sight,” says astronomer Kareem El-Badry.
National Geographic | 8 min readReference: Astronomy & Astrophysics paper

A closer look at lion evolution offers hope for saving the big cats

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A closer look at lion evolution offers hope for saving the big cats



First full-genome lion family tree

Geneticists have reconstructed the relationships of 20 lions, including several extinct ones, by sequencing their genomes. The results support the idea that lions migrated out of Africa, like humans did. Researchers took samples from both living and dead animals, including two 30,000-year-old cave lions (Panthera leo spelaea) preserved in permafrost in Siberia and Canada’s Yukon territory. The findings reveal details about how lions took over the world — they were once the most globally widespread mammal species — and where genetic diversity has been quashed by shrinking populations.
National Geographic | 4 min readSource: PNAS paper

How 'Sustainable' Development Ravaged the Congo Basin - Scientific American

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How 'Sustainable' Development Ravaged the Congo Basin - Scientific American

How 'Sustainable' Development Ravaged the Congo Basin

When conservation goes wrong

In some areas, conservationists have contributed to dislodging people who have lived sustainably for generations. Anthropologist Jerome Lewis saw this happen to the BaYaka Pygmies, who had lived in the forests of Central Africa’s Congo Basin for some 55,000 years. “The formerly active, well-fed and lively BaYaka are now often malnourished, depressed and alcoholic casual laborers dwelling on the edges of their former territories, terrorized by so-called eco-guards and subjected to commercial and sexual exploitation by outsiders.” In various parts of the world, new programmes are now attempting a better approach.
Scientific American | 20 min read

Banksy homenageia profissionais de saúde por sua luta contra o coronavírus | Cultura | EL PAÍS Brasil

Chinese painting


China Daily - Inicio

China Daily - Inicio

China Daily - Inicio

China Daily - Inicio

a paper pheonix

China Daily - Inicio

China Daily - Inicio


China Daily - Inicio

China Daily - Inicio

China Daily - Inicio

Re-entry module of prototype spacecraft makes landing - Chinadaily.com.cn

Re-entry module of prototype spacecraft makes landing - Chinadaily.com.cn

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