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    Paul McCartney is an English singer, songwriter and musician who gained worldwide fame with The Beatles, a rock band formed in Liverpool in 1960. He has collaborated with countless artists over his 60-year career, from Rihanna to Michael Jackson. Now, the former Beatle has teamed up with artificial intelligence (AI). In a recent interview, the 80-year-old revealed that AI has made it possible to release one “last Beatles record.”

    McCartney said that during the creation of the docuseries “The Beatles: Get Back”, produced in 2021 by Peter Jackson, they found an old demo tape that John Lennon had recorded. Through the use of artificial intelligence, they were able to start the process of taking the decades-old recording and turning it into something usable.

    “Peter Jackson was able to extricate John’s voice from an old cassette tape,” McCartney said. “He could tell the machine ‘That’s the voice. This is the guitar. Lose the guitar.’ We were able to take John’s voice and get it pure through this AI,” McCartney continued. “Then we could mix the record as you would normally do.”

    Though McCartney called recent uses of AI in music “kind of scary” — in April, a rap song featuring AI-generated voices mimicking Drake and The Weeknd was yanked from streaming services — the “Let It Be” singer admitted that the technology is “exciting, because it’s the future. There’s a good side to it, and then a scary side. And we’ll just have to see where that leads,” he said.

(Nicolas Vega. www.cnbc.com, 14.06.2023. Adaptado.)

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    They power tiny phones and two-tonne electric cars. They form the guts of a growing number of grid-storage systems1 that smooth the flow of electricity from wind and solar power stations. Without them, the electrification needed to avoid the worst effects of global warming would be unimaginable.

    But lithium-ion (Li-ion) batteries have downsides. Lithium is scarce, for one. And the best Li-ion batteries, those with layered-oxide cathodes, also require cobalt and nickel. These metals are scarce, too — and cobalt is also problematic because a lot of it is mined in the Democratic Republic of Congo, where working conditions leave much to be desired. A second sort of Li-ion battery, a so-called polyanionic design that uses lithium iron phosphate (LFP), does not need nickel or cobalt. However, such batteries cannot store as much energy per kilogram as layered-oxide ones.

    A group of companies, though, think they have an alternative: making batteries with sodium instead. Unlike lithium, sodium is abundant: it makes up most of the salt in the oceans. And chemists have found that layered-oxide cathodes which use sodium rather than lithium can get by without cobalt or nickel to increase their quality. The idea of making sodium-ion (Na-ion) batteries at scale is therefore gaining traction. Engineers are adjusting designs. Factories, particularly in China, are springing up. For the first time since the Li-ion revolution began, lithium’s place on the electrochemical pedestal is being challenged.

(www.economist.com, 25.10.2023. Adaptado.)

¹grid-storage system: sistema de armazenamento de energia elétrica.

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T E X T

Walls, dreams and genocide: Zelensky invokes history to rally support.

    He told U.S. lawmakers that he had a dream, invoking Martin Luther King Jr. to describe Ukraine’s fight against the Russian invasion. He said to the British Parliament that his country would fight until the end, in forests and fields, a vow resonant of Winston Churchill’s exhortations against Nazism. To members of the German Parliament he spoke of a new wall dividing Europe, echoing the Berlin Wall of the Cold War.

    The passionate speeches, delivered remotely by President Volodymyr Zelensky of Ukraine in his now-ubiquitous military-issue shirt, are part of a vigorous rhetorical effort to rally international support — for arms, or aid to his country, or sanctions against Russia.

    Mr. Zelensky, a former comedian who ran a populist campaign to become president in 2019, is no stranger to performing, and his social-media missives and speeches have transformed him into a global symbol of his country’s resistance to Russian aggression. The allusions, metaphors and allegories made by Mr. Zelensky point to a tailored strategy to emotionally appeal to nations and institutions and their histories.

    Mr. Zelensky’s soaring appeal to Congress, which prompted a standing ovation, framed Ukraine’s fight against Russia as a battle to preserve democracy, freedom and the rule of law, calling on the United States’ image of itself as a leader of the free world to defend those values.

    Russia’s attack, Mr. Zelensky said, was a brutal offensive “against our freedom, against our right to live freely in our own country, choosing our own future, against our desire for happiness, against our national dreams — just like the same dreams you have, you Americans.”

    He implored lawmakers to remember two moments of American trauma that involved assaults from the sky to empathize with Ukrainians fleeing missiles: Pearl Harbor and the terror attacks of Sept. 11, 2001.

    He evoked the Rev. Dr. Martin Luther King Jr. to request antimissile defense systems, aircraft and a “no-fly” zone above Ukraine, a step that NATO allies have rebuffed, fearing it would escalate the war with Russia. “I can say I have a need. I need to protect our sky. I need your decision, your help, which means exactly the same, the same you feel when you hear the words, ‘I have a dream.’” he said.

    Mr. Zelensky capped the speech with a direct appeal to President Biden, tailoring his words to appeal to the United States’ role on the global stage. “Being the leader of the world means to be the leader of peace,” he said.

    British lawmakers earlier this month invited the Ukrainian leader for the first ever speech in the House of Commons by a foreign leader. He took advantage of the address to quote Shakespeare and align himself and his cause with Winston Churchill, Britain’s leader during World War II.

    Ukrainians needed to defend their country against the Russians, just as Britons did against Nazism, Mr. Zelensky said. He vowed his country would never surrender to Russian tanks. “We will fight till the end, at sea, in the air,” Mr. Zelensky said in front of the Ukrainian flag, echoing the phrasing of Mr. Churchill in a famous wartime speech: “We will fight in the forests, in the fields, on the shores, in the streets.”

    In his address to the Bundestag last week, Mr. Zelensky urged Germany to take stronger action against Russia, casting the decision as a metaphorical division between building or demolishing a wall — harkening back to the Cold War, an emotional period for Germans. “You are like behind the wall again. Not the Berlin Wall but in the middle of Europe, between freedom and slavery,” he said. “And this wall grows stronger with each bomb that falls on our land, on Ukraine,” he said.

    He called for an embargo on trade with Russia, saying that its ability to keep trading, and keeping Ukraine from joining the European Union, was helping Moscow fortify this metaphorical wall.

    With Canada, Mr. Zelensky mixed a personal, first-name appeal to Prime Minister Justin Trudeau with apocalyptic images of a Canada at war.

    In his address to Canadian lawmakers, Mr. Zelensky referred to the country’s leader simply as “Justin.” And to help them understand Ukraine’s experience, he said, he painted a vivid image of Canadian cities and landmarks under attack.

    He asked lawmakers to envision Canadian flags replaced by Russian ones, Toronto’s CN tower being destroyed by Russian missiles and schools being burned down. “This is our reality,” he said.

    He thanked Canada for its support, but said that what he really wanted was for the country to help bring about a no-fly zone in the skies above Ukraine and to force more companies to leave the Russian market.

From: www.nytimes.com/March 21, 2022

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    The asteroid impact that killed off the dinosaurs gave birth to our planet’s tropical rainforests, a study suggests. Researchers used fossil pollen and leaves from Colombia to investigate how the impact changed South American tropical forests. After the 12 km-wide space rock struck Earth 66 million years ago, the type of vegetation that made up these forests changed drastically.

    The team has outlined its findings in the prestigious journal Science. Co-author Dr Mónica Carvalho, from the Smithsonian Tropical Research Institution in Panama, said: “Our team examined over 50,000 fossil pollen records and more than 6,000 leaf fossils from before and after the impact.” They found that cone-bearing plants called conifers and ferns were common before the huge asteroid struck what is now the Yucatan Peninsula in Mexico.

    But after the devastating impact, plant diversity declined by roughly 45% and extinctions were widespread, particularly among seed-bearing plants. While the forests recovered over the next six million years, angiosperms, or flowering plants, came to dominate them.

  (www.bbc.com. Adaptado.)