【推荐2】Very old people do raise moral problems for almost everyone who comes in contact with them. Their values — this can’t be repeated too often — are not necessarily our values. Physical comfort, cleanness and order are not necessarily the most important things. The social services from time to time find themselves faced with a flat with decaying food covered by small worms, and an old person lying alone in bed, taking no notice of the worms. But is it interfering (干涉) with personal freedom to insist that they go to live with some of their relatives so that they might be taken better care of. Some social workers, the ones who clear up the worms, think we are in danger of carrying this concept of personal freedom to the point where serious risks are being taken with the health and safety of the old.

Indeed, the old can be easily hurt or harmed. The body is like a car, it needs more mechanical maintenance (机械维修，保养) as it gets older. You can carry this comparison right through to the provision of spare parts. But never forget that such operations are painful experiences, however good the results will be. And at what point should you stop to treat the old body? Is it morally right to try to push off death by seeking the development of drugs to excite the forgetful old mind and to activate the old body, knowing that it is designed to die? You can't ask doctors or scientists to decide, because so long as they can see the technical opportunities, they will feel bound to give them a try, on the principle that while there’s life, there’s hope.

When you talk to the old people, however, you are forced to the conclusion that whether age is happy or unpleasant depends less on money or on health than it does on your ability to have fun.

【推荐3】Chinese A-level has overtaken(超过) German for the first time, as it becomes the UK’s third most popular language.

This year 3,334 students take Chinese A-level, compared to 3,058 taking German. While entries(参加总人数) for Chinese have increased by 8. 6 percent since last year, German entries have reduced by 16. 5 percent. French remains the most popular modem language followed by Spanish, but both have seen a fall 1 in entries compared to last year by eight and four percent respectively.

Barnaby Lenon, chair of the Independent Schools Council(ISC), said that although pupils used to be told “It will really help your career if you learn German”, this is no longer the case.

“In the 1960s, 70s and even the 80s, pupils were strongly encouraged to study German because of the importance of the German economy. Although it is still strong, that argument has faded, and China has appeared in the last 25 years as the fastest growing economy in the world. ”

Mr Lenon, former headmaster of Harrow School, said the rise in Chinese A-level entries is partly driven by private schools, many of which have invested in the subject in recent years. “It is not the case that a large number of state schools are now teaching Chinese A-level. They are not,” he said. Many of the entries will be Chinese native speakers and he added that independent schools have attracted “large numbers” of Chinese pupils in recent years.

Mark Herbert, director of schools and skills at the British Council, welcomed the rise in Chinese A-level entries. He said, “Our research shows that Mandarin will be one of the most important languages for the UK’s future and global standing - but we mustn’t neglect Spanish, French and German which will still be vital for post-Brexit(脱欧). ”

Nick Gibb, the schools minister, said, “An outward-looking global nation needs a new generation of young people comfortable with the language and culture of our overseas trading partners. ”

【推荐1】When humans make friends, we often choose companions who share similar characteristics to us or enjoy participating in the same activities that we enjoy. Interestingly, it turns out that dolphins (海豚) may not be so different, according to a study which found that the animals form strong social ties with those who have similar interests. In some ways, this may not be surprising, if we know dolphins live in groups characterized by complex social activities. However, the latest findings are yet another powerful example of the intelligence that these creatures possess.

For the study, an international team of scientists studied a unique group of bottlenose dolphins, who live in the World Heritage area of Shark Bay, Western Australia. They are particularly interesting because the females are known to use sea sponges (海绵动物) as foraging (觅食) tools, a behavior that hasn’t been perceived anywhere else. The behavior known as “sponging,” helps the dolphins to find food in deeper waters and is socially-learned, being passed down from mother to baby.

Previous studies have shown that females in this group who use sea sponges to find food often like to hang out with other females who do the same. However, studies of this behavior in males are lacking, leaving a gap (空白) in our knowledge. To try and address this gap, the researchers collected data on 124 male dolphins in Shark Bay over a 9-year period between 2007 and 2015. Among these dolphins, some had the sponging behavior, while others did not. After analyzing their data, the team came to the conclusion that those males who used sponges for foraging associated significantly more often with other “spongers,” no matter how related they were to their companions. Interestingly, male spongers spent significantly more time foraging and less time resting than non-spongers.

According to the lead author of the study, Manuela Bizzozzero, the findings cast new light on the social ties between male dolphins at Shark Bay.

【推荐2】Balancing Forests and CO₂

Tree planting used to be regarded as an effective means of curbing (抑制) climate change. Perhaps it’s time for us to rethink this practice.

Trees pull carbon dioxide or CO₂ from the air. This effectively removes CO₂ from the atmosphere, making trees an important part of the fight against climate change. But trees only hold onto carbon dioxide as long as they’re alive. Once they die, trees decay (腐烂) and release that CO2 back into the atmosphere. This movement of carbon between forest and the atmosphere is called a carbon flux (碳通量), a natural process that happens as trees grow and eventually die.

Recent studies have found that trees around the world are growing faster than ever. Rising atmospheric CO2, mainly due to burning fossil (化石) fuels, is probably driving that rapid growth, said Roel Brienen, a forest ecologist at the University of Leeds, UK. High levels of this gas are boosting temperatures, which in turn speeds tree growth in those areas, he added.

The faster trees grow, the faster they store carbon. It seems like good news. However, it is known that fast-growing tree species, in general, live shorter lives than their slow-growing relatives.

In order to see whether the growth-lifespan trade-off (生长和寿命之间的权衡) is a universal phenomenon, Brienen and his colleagues analyzed over 210,000 individual tree ring records of 110 tree species from more than 70,000 sites worldwide. “By measuring tree rings’ widths one can tell how fast trees grew, while counting rings provides information on tree ages and allows making inferences about trees’ maximum lifespan,” Brienen explained.

They found that, in almost all habitats and all sites, faster-growing tree species died younger than slow-growing species, and even within a species, the trade-off between growth and lifespan held strong.

The team also created a computer program that modelled a forest and adjusted the growth of the trees in this model. Early on, it showed that “the forest could hold more carbon as the trees grew faster”, Brienen reported. But after 20 years, these trees started dying and losing this extra carbon again. “We must understand that the only solution to bring down CO₂ levels is to stop emitting (排放) it into the atmosphere,” said Brienen.

【推荐3】A company in San Francisco, California, has found a way to turn used plastic bottles into women’s shoes.

Every day, millions of Americans drink water and other liquids from plastic bottles. More than 60 million of them are thrown away each day. Many of the plastic bottles end up in landfills or are burned with other waste products.

A San Francisco start-up company called Rothy’s, however, turns this plastic waste into environmentally friendly shoes. Roth Martin, the company’s co-founder, explains how they turn plastic into soft material for women’s feet. They take the plastic, clean it, and break it down into small pieces. Then they press them through a device that makes soft fibers. Those fibers are then combined together. This is done by a 3D machine. It is designed to reduce waste while making the shoes. The processed stuff and the inner part of the shoes are then attached to the shoes’ outer part, called the sole (鞋底). This outer sole is also made from eco-friendly material.

Rothy’s shoes are sold online. They are flat shoes, with different colors and designs. They cost either $125 or $145 per pair, depending on the design. After American actress Gwyneth Paltrow discovered them last year, the demand for the shoes grew. Martin says there is no shortage of material to fill that demand. “We’re not going to run out of water bottles any time soon, so we have a limitless supply of material, and I think that is a good sign for our future.” When the environmentally friendly shoes wear out, customers can return them at no cost to a company that uses the recycled material to make other products.

For now, the shoes are only available to be shipped in the United States. However, the company says it will add international transport in the near future.

【推荐1】In this Pennsylvania city, Pittsburgh is shrinking but getting wealthier. Since 2000, its population has declined by 95,000 while its income per capita (人均) has shot up 24 percent. The trend is taking hold in many other cities, like Buffalo in New York, Providence in Rhode Island and New Orleans.

Some of these areas have created more high-paying jobs in energy, health care or education. Others have managed to reshape their producing industry for a new economy. Higher-paying jobs have a greater effect because they create demand for additional services. "The story in Pittsburgh is very positive, and other areas are looking at it as an example of the transformation that might be possible,” said Guhan Venkatu, who wrote an economic history of the area called “Rust and Renewal” for the Federal Reserve Bank of Cleveland.

Carnegie Mellon University and the University of Pittsburgh have helped bring tech jobs and innovation(革新) to the area by sponsoring tech centers that help graduates start companies without moving to Silicon Valley or San Francisco. This has helped keep Pittsburgh's educated young population growing even as the entire population in the city has dropped.

Pittsburgh has more STEM (science, technology, engineering and math) jobs than other shrinking cities, about 80, 000 or 7% of all jobs. STEM jobs add productivity and income growth to the area. Manufacturers of high-tech medical equipment in the Pittsburgh area also have doubled employment in the last 10 years.

However, some experts question whether growing income per capita can really make up for a declining population. According to Patrick Adler, a researcher at the University of Toronto, population loss does matter if it means lower-skilled workers have fled because of a lack of opportunity. What's more, high-paying jobs in education and health care can disappear if the population declines too greatly. So it'd be wise to find ways to increase the population.