1 . A six-year-old longing to keep a unicorn in her backyard figured she’d get the hard part out of the way first.

Last November, Madeline wrote a letter to the Los Angeles County Department of Animal Care and Control with a straightforward request. “Dear LA County, I would like your approval if I can have a unicorn in my backyard if I can find one. Please send me a letter in response.”

Director Mayeda replied two weeks later. The department does in fact license unicorns, she said, under certain conditions. Those include polishing the unicorn’s horn at least once a month with a soft cloth, feeding it watermelon at least once a week, covering it with only nontoxic and biodegradable sparkles and giving it regular access to sunlight, moonbeams and rainbows. And, because unicorns are indeed very rare to find, the department is also giving Madeline a toy unicorn to keep her company during her search, as a token of appreciation.

“It is always rewarding to hear from young people who thoughtfully consider the requirements of providing a loving home for animals,” Mayeda wrote in the letter. “I like your sense of responsible pet ownership to seek permission in advance to keep a unicorn in Los Angeles County.”

Mayeda told the Washington Post that this is the first time the department has received a request for a license for a unicorn or any mythical creature. They were impressed with the first-grader for wanting to ask permission in the first place, and doing her research to work out how to go about that. She and her colleagues deal with a lot of “life-and-death” issues on the job, whether that’s seeing cases of animal abuse or animals hurting people or making decisions about having to put down dangerous or sick animals. So Madeline’s letter has considerably brightened their spirits, and she is due to visit the department this week to discuss her unicorn license application. Safe to say, she’s in for a magical surprise.

2 . To prevent tsunami-caused disasters, several countries worked together to expand the use of a tsunami-detecting system that had been developed in the United States by the National Oceanic and Atmospheric Administration (NOAA). The system________ of an instrument installed on the seafloor — called a tsunameter — that measures pressure changes caused by a passing tsunami. The tsunameter sends a signal to a surface buoy (浮标), which sends the data to a satellite, which ________ the information to warning centers around the world.

By 2004 only six such detectors had been installed, all in the Pacific. There were________ in the Indian Ocean, and many countries in the region had no national warning centers that could have ________ local communities. That policy mistake had tragic consequences. In Sumatra people had only a few minutes to run, ________the tsunami took two hours to reach India, and some 16,000 people died there. “It was totally unnecessary,” says Paramesh Banerjee, a geo-physicist at Nanyang Technological University in Singapore. “Technically it would have been relatively ________ to install a tsunami warning system for the Indian Ocean.”

There are now 53 detector buoys operating in the world’s oceans, including 6 of a planned 27 in the Indian Ocean. So a (n)________ of the 2004 horror, in which the tsunami traveled for hours and still caught people by ________ is less likely. But buoys would not have helped in Sumatra. People living on coasts near a rupturing fault (地壳断层) can’t wait for ________ that a tsunami is on its way, which it often isn’t; they must flee as soon as the quake hits. The Japanese warning system relies not only on tsunameters but also on seismometers (地震测量仪) — a thousand of them ________ the country, the densest network anywhere — combined with a computer model that forecasts the scale of a tsunami from the magnitude (震级) and ________ of the quake.

In March, the system, which is run by the Japan Meteorological Agency (JMA), did not work perfectly. JMA’s initial ________, while the ground was still shaking, put the quake magnitude at 7.9 — but later analysis revealed a quake that, at magnitude 9, was 12 times larger. The tsunami forecast warned of waves of ten feet or more — but they reached 50 feet in Minanisanriku and in some places even ________. But the human ________ to the warning was imperfect as well. “I think this time many people who lived above the high-water mark of the 1960 tsunami didn’t bother to run.” says Jin Sato, mayor of Minanisanriku. “Many of them died.” The town’s seawall, he thinks, also gave people a false sense of ________

3 . When it comes to black holes, we are caught between a rock and a hard place. In the 1970s, Stephen Hawking showed that all black holes give off thermal radiation(热辐射)and eventually evaporate(蒸发). In doing so, they seemed to be destroying information contained in the matter that fell into them, therefore going against a rule of quantum mechanics(量子力学): information cannot be created or destroyed.

Some argued that the outgoing “Hawking radiation” preserved the information. However, if this were the case, then given certain assumptions, the event horizon(视界)—— the black hole’s boundary of no return—— would become intensely energetic, forming a firewall. But such firewalls go against the theory of general relativity, which says that space-time near the event horizon should be smooth. The black hole firewall paradox was thus born.

Now, Sean Carroll at the California Institute of Technology and his colleagues have shown that the paradox disappears when the evolution of black holes is understood in the context of the many-worlds interpretation of quantum mechanics.

The quantum state of the universe is described by something called the global wave function(全局波函数). According to traditional quantum mechanics, whenever there are many possible outcomes for physical process, this wave function ”collapses“ to represent one outcome. But in the many-worlds Interpretation, the wave function doesn’t collapse-rather, it branches, with one branch for each outcome. The branches evolve independently of each other, as separate worlds.

In this way of thinking, the formation of a black hole and its evaporation due to Hawking radiation lead to multiple branches of the wave function. An observer monitoring a black hole also splits into multiple observers, one in each branch.

The new work shows that from the perspective of an observer in a given branch, space-time behaves as described by general relativity and the black hole has no firewall.

But does that imply loss of information? No, says team member Aidan Chatwin-Davies, also of Caltech. That is because the principle of preservation of information applies to the global wave function and not to its individual branches, he says. Information is preserved across all branches of the global wave function, but not necessarily in any one branch. Given this case, a black hole that doesn’t lose information and yet has a smooth, uneventful event horizon without a fire wall isn’t a contradiction.

Yasunori Nomura at the University of California at Berkeleyy has independently arrived at some similar conclusions in his work. He agrees that the many-worlds approach resolves the paradox around information loss from black holes. “Many worlds should be taken seriously,” he says.

6 . An exhibition of vivid photographs and a restored documentary give fresh insight into the Antarctic explorer, who died a century ago.

One hundred years ago, the leader of the last great expedition of the heroic age of polar exploration died from a heart attack as his ship, Quest, headed for Antarctica. The announcement of the death of Ernest Shackleton on 30 January 1922 was greeted with an outpouring of national grief.

This was the man, after all, who had saved the entire crew of his ship Endurance — which had been crushed and sunk by ice in 1915 — by making a daring trip in a tiny open boat over 750 miles of polar sea to raise the alarm at a whaling station in South Georgia.

It remains one of the greatest rescue stories of modern history and led to the idolising of Shackleton in the United Kingdom, a reputation that survived undamaged for the rest of the century. As his contemporary Raymond Priestley, the geologist and Antarctic explorer, later put it: “When disaster strikes and all hope is gone, get down on your knees and pray for Shackleton.”

And here and now in 2022, his death is being marked with an elaborately illustrated exhibition — Shackleton’s legacy and the power of early Antarctic photography — which opens at the Royal Geographical Society (RGS), and which includes a range of images and artefacts from his expeditions. Additionally, a digitally remade version of South, a documentary film of Shackleton’s 1914-16 Endurance expedition, is being screened at the British Film Institute.

The film and most of the exhibition’s finest images are the handiwork of Frank Hurley, who sailed with Shackleton and who was one of the 20th century’s greatest photographers and film-makers. Both film and exhibition feature striking camera work and provide vivid accounts of the hardships that Shackleton and his men endured as they headed off to explore Antarctica.

Even after he survived the great expedition, he still longed for another trip to Antarctica, and after long negotiations set sail in Quest, from England, with the aim of circumnavigating (环航) Antarctica, Shackleton was by now very ill and had suffered at least one heart attack. On 2 January 1922, he wrote in his diary: “I grow old and tired but must always lead on.” Three days later he had a major heart attack and died a few hours later. He is buried on South Georgia, scene of his greatest triumph.

“Shackleton was an inspirational leader. He had an innate sense of what was possible and achievable. He also had a huge personality but led by example. At the same time, he was sensitive to the needs of the individuals he was leading. For example, after Endurance broke up, his men had lost their protection and shelter. Their social fabric had been destroyed. There would have been disagreement. Yet Shackleton succeeded in keeping them together and made sure they survived.”

7 . In 2004, Pen Hadow became the first person to trek (跋涉) to the North Pole alone, without being resupplied on the way. That meant swimming through unimaginably cold waters, and risking encounters with polar bears. Just eight months later, he made a similar trip to the South Pole. Now he is back in the Arctic again, preparing for an expedition (远征) he says is even more ambitious. Explorers are confident, driven individuals. They have to be. This time, however, more significance is attached. Pen and two colleagues will set out on a three-month, 1000-kilometre trek to the North Pole, taking detailed measurements of the thickness and density of the ice. Nobody has ever done this before, and he knows the results will be of vital significance to the scientific community. This will be the truest picture yet of what global warming is doing to the ice that covers the polar region.

Pen and his wife, Mary, live in the country with their two children. “It’s much harder to be away from them this time,” he admits. They were one and five when I last went, and I made a mistake in the way I said goodbye. I thought it would be a good idea to say to my son, “You’re the man of the house now, look after your mum and your sister.” He absolutely took it to heart, asking his mum how she was all the time, but the stress eventually became too much. While it was well intentioned, it was an unfair thing to do.

He is spending these last days before departure preparing his things. “Out on the ice, one is virtually unable to mend things or do anything that isn’t absolutely straightforward,” he says. With him will be Ann Daniels, one of the world’s leading polar explorers, and the photographer, Martin Hartley. They will be supported by a crew of six, flying in supplies. Being part of a team is actually more stressful to someone with his mentality, says Pen, and something else is on his mind too. “I’m going to be 47 on Thursday. I’ve done far less training than I’m comfortable with.” Why? “Organisational things always seem more urgent. So I’m almost fearful of what I’m going to ask of myself.”

Pen believes his mission reconnects exploration with the search for knowledge that drove previous generations into the unknown. “Making it to the North Pole was a personal ambition,’”he admits, “and of limited value to anyone beyond the polar adventuring community. This time, scientists will profit from the data, and we’re creating a platform in which to engage as many people as possible in what’s happening in the Arctic Ocean. This is important work, and nobody can do it but us,” he says. “Our skills, which are otherwise not that necessary, have become really relevant. Suddenly, we’re socially useful again.”

Uber Eats pilots reusable container scheme

From today (Tuesday 18 April, 2023) Uber Eats customers in Central London will be given the option to order their takeaway in reusable containers and easily return them in an attempt     1     (address) single use packaging.

    2     (Bring) together various businesses, the project will test and measure how localized doorstep at-home collections of reusable packaging can increase the adoption rate of a reuse system and improve convenience. The system has been developed to make     3     as easy and convenient as possible for people to take part. When placing their orders, Uber Eats customers can choose to receive their food in reusable packaging. Once they’ve enjoyed their meals,     4     they need to do is to scan a QR code, select a day for collection, give the containers a simple rinse and await collection. All collections are low or no emissions,     5     (make) by deliverymen using bikes, electric cars or vans.

The trial will run for six months and will be managed by Again, which operates a network of packaging cleaning facilities     6     the reusable packaging will be cleaned and processed before being returned to the restaurants. Various promotions     7     (test) throughout the trial to measure opt-in rate and return rate. “This pilot aims to make reusable packing     8     (accessible) for customers and restaurants alike,” says Matthew Price, Uber Eats General Manager. “By integrating the reuse option     9     a delivery app used by many households and by offering doorstep collections, we hope to see a significant increase in the use of reusable takeaway packaging. The trial will help create     10     better understanding of what works and what doesn’t at a local level, and hopefully lead to wider roll out of this reuse system across more businesses and areas.”

Throughout the world, only 15% of the material that are used to make clothing is properly recycled, according to the Alle SacUrthur Club, an organization in Liverpool, UK, that boosts the circular economy. Most clothing waste—an     1    (estimate) 82 million tonnes from the fashion industry alone-produced every year ends up buried or burnt.

    2    (handle) all that waste, methods to recover and reuse the material are intended as an active response to the future risks by researchers and start-up companies. Much of their focus is on chemical recycling,     3     the material is broken down into its building blocks and applied to create new materials, including fibres that     4     (weave) into new clothes. The challenges lie in     5     (develop) the processes for such treatment. They have to be practical, but they also have to be at least as cost-effective as simply making new fibres.

    6     the natural cellulose fibres from cotton, some other materials include human-made cellulosic fibres. They are derived from wood-pulp cellulose and may be used to produce materials such as viscose (rayon) and a similar material called lyocell.

A change in the manufacturing process is being applied to the textile-waste problem by Essen, a start-up in Seattle, Washington.     7     the company has fundamentally devoted to the process is that it uses discarded textiles, instead of wood, as the source of its cellulose. It has also adjusted the process to produce a fibre that the firm’s co-founder and president Christo Stan says is superior to     8     other cellulosics and cotton, and that can be recycled more times.

Although there are abundant technical challenges, the main barrier     9     widespread textile recycling could be economic, says materials engineer Lijiang Jiang at the Massachusetts Institute of Technology in Atlanta. “Most of the materials are not that invaluable,” Jiang says. So cheap it is to produce polyester, cotton and other fabrics     10     there’s little profit margin unless the recycling processes themselves are very inexpensive.