A report says older adults who test their minds with increasingly difficult projects have better mental ability than those who do less demanding activities.

    To keep our brains sharp as we age, we are often told to keep our minds active. As the old saying goes, “Use it or lose it.” But, there is very little scientific evidence to support than.

Denise Park is head of the university's Center for ? Vital Longevity. She designed a study in which she and her tern placed 221 healthy aging and older adults into one of three groups.

    “We asked people to learn new things, like quilting or photography. We asked other people to just do fun things like being in a social group function but were not likely to have a very large effect.”

    The subjects took part in their assigned activities for 15 hours a week over three months. At the end of that time, the researchers found that the adults who learned new skills, such as digital photography, showed the greatest improvements on memory tests.

    No improvements were seen in the results of those in the social group that did activities together like going on field trips. There were also no improvements among the third group that listened to classical music or did crossword puzzles.

    Denise Park believes one reason for improved memory in the active learning group is that its members were being pushed to learn new skills. The other groups took part in what she call receptive activities. Learning new skills may not cure age-related mental decline. But, Ms. Park thinks being mentally active slows down the process.

Denise Park says the latest information shows that the improvements lasted for at least a year. She and her team plan to do longer follow-up studies with all three groups. She also is interested in learning whether taking part in demanding mental activities delays the development of conditions like Alzheimer's disease.

    People from Britain and Ireland first came to live in Australia in 1788. They brought different dialects （方言）of English with them. These different kinds of English began to mix and change. The newcomers soon began to speak with their own typical accent（口音） and vocabulary. More and more people came to Australia during the Gold Rush in the 19th and 20th centuries. Some came from Britain and Ireland; others came from non-English speaking countries. Australian English continued to grow and change.

    Australian English has also been influenced by American English. During the Second World War, there were many American soldiers staying in Australia. More importantly, American television shows and music have been popular in Australia since the 1950s.

    Australians use many words that other English speakers do not use. The famous Australian greeting, for example, is G'day! A native forest is called the bush and central Australia is called the outback. Many words were brought to Australia from Britain and Ireland. For example, mate means "friend", and it is still used in Britain. Some of these words have changed in meaning. Some words have come from Australian original languages, many of which are names for animals, plants and places, like dingo and kangaroo.

    Australian spelling comes from British spelling. In words like organise and realise, -ise is the expected and taught spelling method. In words like colour, favourite, -our is the normal, but nouns such as the Labor Party and Victor Harbor are spelled with -or. Program, on the other hand, is more common than programme.

    There are also differences in the definition （定义）of words Australians use in different parts of the country. For example, football means "rugby" in New South Wales and Queensland, but "Australian rules football" in everywhere else in Australia. In New South Wales, a swimming costume is called a cossie or swimmers, while in Queensland it is called togs and bathers in Victoria.

    Back in 2009, China was wrongly accused by the West of "controlling" the Copenhagen talks on climate change. By then China had truly carried out strict policies to reduce the energy consumption of economic activities and at the international level, the top Chinese leaders participated in round-clock efforts to cooperate with the major players to build a united front for efforts to solve global warming. But China was finally misjudged.

    This misjudgment caused China's scholars to rethink China's climate change communicative ways. Among them was Zheng Baowei, journalism professor of Renmin University of China, who realized China had to better shape its communication on its environmental protection.

    Delightfully, the efforts have paid off. Zheng set up a top-level international group advising his research team. He is in charge of doctoral candidates on climate change communication. Climate awareness surveys have been conducted, and a package of communication tools has been designed. Many seminars have been arranged.

    Recently, he arranged a seminar on climate change and health communication on the changing situation both in China and the world. First of all, this stressed that China's policy has developed from reducing its energy consumption and pollution prevention to the important goals of achieving a "Beautiful China" and "'Healthy China, "while coming up with plans to realize an ecological civilization since late 2012. With such goals, China played a leading role in securing the Paris climate change deal in 2015 together with the United States and European Union. In Paris, China promised to let out its carbon to the maximum in 2030.

    It is a demanding job communicating climate change and other topics of lasting development well. Despite that, some foreign scholars have realized China's smart ways in presenting the green concepts. They appreciated China's idea of building a "Beautiful China" and "Healthy China" and said it can he expanded into an idea of a "Beautiful World" and "Healthy World".

    Looking back from how China had followed the steps of the industrialized countries in advocating climate fight, people find now its own green ideas are being recognized.

Keeping secrets is a burden

    “Don't tell anyone”. We hear these words when someone tells a secret to us. But it can be hard to keep a secret. We're often tempted to “spill the beans(说漏嘴)”, even if we regret it later.

    According to Asim Shah, professor in the Menninger Department of Psychiatry and Behavioral Sciences at Baylor College of Medicine, US, keeping a secret may well “become a burden”. This is because people often have an “obsessive and anxious urge to share it with someone”.

    An earlier study, led by Anita E. Kelly, a scientist at the University of Notre Dame, US, suggested that keeping a secret could cause stress. People entrusted(受委托的) with secrets can suffer from depression, anxiety, and body aches, reported the Daily Mail.

    But with secrets so often getting out, why do people share them at all? Shah explained that people often feel that it will help them keep a person as a friend. Another reason people share secrets is guilt over keeping it from someone close to them. A sense of distrust can develop when people who are close do not share it with each other. “Keeping or sharing secrets often puts people in a position of either gaining or losing the trust of someone,” according to Shah.

    He added that talkative people could let secrets slip out (泄露).But this doesn't mean that it is a good idea only to share secrets with quiet people. A quiet person may be someone who keeps everything inside. To tell such a person a secret may cause them stress, and make them talk about the secret. Shah said that to judge whether to tell someone a secret.

    Shah said that to judge whether to tell someone a secret, you'd better put yourself in their position. Think about how you would feel to be told that you mustn't give the information away. Shah also recommended that if you accidentally give up someone's secret you should come clean about it. Let the person know that their secret isn't so secret anymore.

    In the 1960s, while studying the volcanic history of Yellowstone National Park, Bob Christiansen became puzzled about something that, oddly, had not troubled anyone before: he couldn't find the park's volcano. It had been known for a long time that Yellowstone was volcanic in nature—that's what accounted for all its hot springs and other steamy features. But Christiansen couldn't find the Yellowstone volcano anywhere.

    Most of us, when we talk about volcanoes, think of the classic cone (圆锥体) shapes of a Fuji or Kilimanjaro, which are created when erupting magma (岩浆) piles up. These can form remarkably quickly. In 1943, a Mexican farmer was surprised to see smoke rising from a small part of his land. In one week he was the confused owner of a cone five hundred feet high. Within two years it had topped out at almost fourteen hundred feet and was more than half a mile across. Altogether there are some ten thousand of these volcanoes on Earth, all but a few hundred of them extinct. There is, however, a second les known type of volcano that doesn't involve mountain building. These are volcanoes so explosive that they burst open in a single big crack, leaving behind a vast hole, the caldera. Yellowstone obviously was of this second type, but Christiansen couldn't find the caldera anywhere.

    Just at this time NASA decided to test some new high-altitude cameras by taking photographs of Yellowstone. A thoughtful official passed on some of the copies to the park authorities on the assumption that they might make a nice blow-up for one of the visitors' centers. As soon as Christiansen saw the photos, he realized why he had failed to spot the caldera; almost the whole park-2.2 million acres—was caldera. The explosion had left a hole more than forty miles across—much too huge to be seen from anywhere at ground level. At some time in the past Yellowstone must have blown up with a violence far beyond the scale of anything known to humans.

Diving in the ocean, marine biologist Erika Woolsey has seen how coral reefs (珊瑚礁) are being damaged by climate change. It has made her decide to find a way to share her experience —including those who can't easily explore the ocean.

Through her non-profit, The Hydrous, Woolsey is using virtual reality to bring the ocean to everyone. Scientists, filmmakers and divers are taking people on immersive (沉浸式的) virtual dives, attracting attention to reef damage and expecting action to protect our sea. About 25% of marine species depend on coral reefs. However, climate change, pollution and overfishing have done harm to around half the world's shallow water coral reefs.

Twenty years of underwater exploration has given Woolsey a detailed understanding of the dangerous situations facing reefs. "I've seen this first-hand shift. Healthy colourful coral reefs become what look like the moonscape step by step," Woolsey says.

It is through this experience that The Hydrous team set out to recreate with their award-winning film Immerse. Intended to watch with a VR headset, viewers join Woolsey for a nine-minute guided virtual div e on the coral reefs, immersed in a 360-degree underwater view.

They swim alongside sea turtles and sharks before witnessing the worsening of the reefs. The experience often brings out strong feelings. "As soon as people take off that headset and look me in the eye, they want to tell me a story about their ocean experience," Woolsey says. "It's that human connection to our ocean that will solve our ocean problems."

Woolsey hopes advances in camera technology will allow her team to take more and more people to places in the ocean that are underexplored and places further away from human civilization. They are developing a virtual experience that will put the people in the role of a marine biologist, carrying out biodiversity surveys underwater, and even transporting the viewers to space to monitor global sea surface temperatures.