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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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This couple’s jungle honeymoon became a total nightmare

by Jane Ridley

[1]    It was the going to be a weeklong romantic adventure for Holly Fitzgerald, now 71, and her husband,
Fitz, 70, rafting like Huck Finn down a fast-flowing tributary of the Amazon. Instead, it wound up becoming
a nearly month long ordeal, stranding two honeymooners on a parasite-ridden lake in the Bolivian jungle
– with nothing to eat but slugs, snails and frogs.
[5]    The epic tale began in February 1973, five months into the couple’s yearlong honeymoon backpacking
around South America. There was a general plan to reach Rio de Janeiro and then board a ship bound
for Africa, but the newlyweds were frequently sidetracked while meeting interesting people en route. One
such encounter, with some anthropologists, aroused their curiosity about the Amazon basin. So they
booked seats on a small plane to the Peruvian frontier town of Puerto Maldonado. It would be their first
[10] mistake. “The wobbly plane began to descend very fast, pushing me sideways, causing me to grasp the
seat,” Holly writes in her book. “We were thrown back and forth, held by our wide seat belts . . . I caught
sight of the plane’s right wing and engine out of the window. They’d been snapped entirely.”
    The DC-3 – with 13 people onboard – crash-landed in the jungle. Incredibly, no one was badly hurt
in the accident, which was likely a result of pilot error. The survivors were escorted across a river to the
[15] nearest shelter: an open penal colony full of convicted murderers and rapists. Although the passengers
slept in separate barracks from the inmates, there was a sense of menace in the air. Despite daily promises
from prison guards that help was on the way, it was four long days before a plane appeared on the muddy
pasture that served as a runway. When they finally reached Puerto Maldonado, the Fitzgeralds discovered

they’d missed their boat to Bolivia. It was flood season, and the next available trip downriver was likely
[20] three months away.
    Encouraged by locals, the young couple decided to build a raft – using four logs and a makeshift tent
fashioned from plastic sheeting lined with mosquito netting – and navigate 500 miles of the Madre de
Dios river to Riberalta, Bolivia, themselves. “At first, it was idyllic,” recalled Holly, who reveled in the jungle
scents of ripe mangoes and gardenia.
[25]    However, on their fourth night, fortunes changed. While the couple was sleeping, a raging thunderstorm
brewed. Torrential rain pelted the tent, threatening its collapse. “Just then, something slammed the bow,
pulling the raft downwards,” Holly writes. She heard the horror-movie rip of the plastic tent as a large tree
trunk crashed through, pinning her to the raft. Her husband struggled to pull the tree off her as the small
watercraft rocked back and forth, threatening to capsize at any second.
[30]    Once the storm quieted, the sun soon came up to reveal a frightening reality: The couple were now
off course, with no idea of their location. “We didn’t know it at the time, but we were stranded in the middle
of a swamp – a seasonal lake formed because of flooding,” said Holly. “Most of our food and supplies had
fallen overboard during the night. Our tent was ripped to shreds, so we had to replace it with spare plastic
sheeting we’d managed to hold onto”.
[35]    As the land around them was submerged, there was no question of getting anywhere on foot. Tying
the raft and their few remaining possessions to a bush above the water line, the duo swam for hours at a
time – only to travel less than half a mile. They gave up after trying for two days.
    For 26 days, they were marooned – knowing no one was looking for them, as they had written to their
family that they’d be exploring for at least a month. The couple were besieged by bees, mosquitoes and
[40] other biting insects. They tried to catch fish but had zero luck. Strange noises from the jungle terrified
them at night, and they felt themselves weaken by the hour. Holly and Fitz became skeletal and frequently
doubled over in pain because of the lack of food. One morning, Holly initially couldn’t wake her husband
and feared he had died in his sleep.
    On their 26th day in the swamp, Holly had a premonition. “We’re going to make it out of here. I just
[45] know it,” she told her ailing husband, who lost 40 pounds during the ordeal. (Holly herself shed 20 pounds.)
Hours later, after nearly a month of not seeing a single soul, they spotted two Indians hunting turtles from
a canoe. Using made-up hand signs and broken Spanish, the honeymooners convinced the men to take
them to their village. They later traveled to their original destination of Riberalta.
    Over the next two weeks, the Fitzgeralds were treated in a hospital for exhaustion, severe malnutrition,
[50] and the bites and stings they’d received. In April 1973, they finally returned home.
    Remarkably, their brush with death didn’t curb the couple’s enthusiasm for travel. They have since
visited far-flung destinations including Bali, Malaysia, Ethiopia, Sudan and the Himalayas. “With hindsight,
it does seem rather bold to have taken the raft on such a big river, but I can’t say I have deep regrets,” said
Holly. “The whole experience brought Fitz and I closer together. 

Disponível em: https://nypost.com/2017/07/22/this-couples-jungle-honeymoon-became-a-total-nightmare/. Acesso em: 10 ago. 2021. (Parcial e
adaptado.)

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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.)