When a leafy plant is under attack ，it doesn't sit quietly. Back in 1983, two scientists, Jack Schultz and Ian Baldwin,reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be an alarm.What the plants pump through the air is a mixture of chemicals known as volatile organic compounds,VOCs for short.

Scientists have found that all kinds of plants give out VOCs when being attacked .It's a plant's way of crying out.But is anyone listening?Apparently.Because we can watch the neighbours react.

    Some plants pump out smelly chemicals to keep insects away.But others do double duty .They pump out perfumes designed to attract different insects who are natural enemies to the attackers. Once they arrive, the tables are turned. The attacker who was lunching now becomes lunch.

    In study after study,it appears that these chemical conversations help the neighbors .The damage is usually more serious on the first plant,but the neighbors ,relatively speaking ,stay safer because they heard the alarm and knew what to do.

Does this mean that plants talk to each other? Scientists don't know. Maybe the first plant just made a cry of pain or was sending a message to its own branches, and so, in effect, was talking to itself. Perhaps the neighbors just happened to “overhear” the cry. So information was exchanged, but it wasn't a true, intentional back and forth.

    Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate(亲密的) than the world we can see and hear. Our senses are weak. There's a whole lot going on.

    Optimism May Help People Live Longer

People who have an optimistic view on life are more likely to live longer, a US study said Wednesday.

    The study, published in the American Journal of Epidemiology, analyzed data from 2004 to 2012 from 70,000 women enrolled in the Nurses' Health Study, a long-running US study tracking women's health via surveys every two years.

    The researchers looked at participants' levels of optimism and other factors that might play a role in how optimism may affect mortality risk, such as race, high blood pressure, diet, and physical activity.

    It found the most optimistic women, or the top 25%, had a nearly 30 percent lower risk of dying from any of the diseases analyzed in the study compared with the least optimistic women, or the bottom 25%.

    The most optimistic women had a 16 percent lower risk of dying from cancer; 38 percent lower risk of dying from heart disease; 39 percent lower risk of dying from stroke; 38 percent lower risk of dying from respiratory disease; and 52 percent lower risk of dying from infection.

    Previous studies have linked optimism with reduced risk of early death from cardiovascular (心脑血管的) problems, but this was the first to find a link between optimism and reduced risk from other major causes.

    “While most medical and public health efforts today focus on reducing risk factors for diseases, evidence has been mounting that enhancing psychological resilience (弹性，复原力) may also make a difference,” said Eric Kim, research fellow at the Harvard T.H. Chan School of Public Health and co-lead author of the study.

    “Our new findings suggest that we should make efforts to boost optimism, which has been shown to be associated with healthier behaviors and healthier ways of coping with life challenges.”

    The study also found that healthy behaviors only partially explain the link between optimism and reduced mortality risk. One other possibility is that higher optimism directly affects our biological systems, Kim said.

    Co-lead author and postdoctoral research fellow Kaitlin Hagan said optimism can be varied with relatively uncomplicated and low-cost interventions (干预), even things as simple as having people write down and think about the best possible outcomes for various areas of their lives, such as careers or friendships.

    “Encouraging use of these interventions could be an innovative way to enhance health in the future,” Hagan said.

    When mentioning China, what comes to mind? As a country with a history of more than 5000 years, China is rich in civilization and culture. What best represents China?

Confucius (551BC - 479 BC)

    Confucius was a teacher and philosopher from the Spring and Autumn Period of Chinese history. The philosophy of Confucius stresses individual morality including kindness, fairness, politeness, and sincerity. Confucius' principles have a broad basis in common Chinese tradition and belief.

Dragon

    A dragon is a legendary creature, typically with winding or crawling characters. The dragon symbol is frequently used on ancient Chinese emperor's items including chairs or costumes. It is considered a representation of power.

Peking Opera

    Peking Opera is considered the essence of China. As the larger form of Chinese opera, it has many “firsts” in Chinese dramas: the abundance of talents, the number of artists, opera groups and audience.

The Great Wall

    There is an old saying that goes, “He who has never been to the Great Wall is not a true man.” The Great Wall, one of the greatest wonders of the world, is a destination one must see when visiting China.

Traditional Chinese Medicine (TCM)

    Developed in China, TCM has a tradition dating back to more than 2,000 years, including various forms of herbal medicine, cupping, massage, exercise (Qigong), and dietary therapy.

    In an attempt to make the group texting experience more bearable, we've put together a list of strategies and things to consider when messaging multiple people at the same time.

    Think about who you're texting

    Whether you're in a group text with your parents, schoolmates, or work friends, consider what you're sharing - and who you're sharing it with. Parents may not be interested in the latest memes and explaining their slight differences can be a pain.

    Be mindful of people's schedules

    While not everyone's schedules are the same, most people are busy during typical work week hours, so sending a million mid-day texts isn't always ideal. Some people rise early or get to bed early. Avoid including them on a text that you know will ask for a bunch of responses super late at night or early in the morning.

    Name the group

    If you have the ability to name the texting or messaging group you're on - this is possible on an iPhone or when using Facebook Messenger - I strongly recommend you do so. Though not everyone will love the name you choose, naming your group will help you keep track of all your ongoing conversations.

    Don't write lots of one-word texts

    Please, if you must text in the group thread, don't deliver multiple short answers in a row. Everyone will despise you. If you have something pressing to share or say, try to sum it up in one brief text. If you have a lot to say, maybe try writing an email.

    Damn I seriously don't have time to be on my phone when I'm at work, and my friends keep texting on the group chat and I'm at a loss.

    - Melzz (@_Melzzxx) November 17, 2018

    Much older than the Great Wall, Stonehenge is one of the world's most fascinating (迷人的), but least understood historical sites (遗址). Every year, thousands of tourists come to admire Stonehenge's beauty and to wonder about how and why it was built.

    Stonehenge was produced by a culture that left no written records. Though there are many guesses, it is still a mystery why stone-age man moved such heavy stones over 380 kilometers from where they were made.

    At that time, people had only basic wooden tools. To move the stones they probably used tree trunks (树干) to roll them along.

    Some historians believe that Stonehenge was a temple, the site of ancient sacrifice(祭祀). Others believe it was perhaps a giant sundial (日冕) to tell the time. Stonehenge could have been a burial ground(墓地) from its earliest beginnings, because human bone dating from as early as 3000 BC was found there. Whatever its ancient use was, the stones have always been a source of fascination for British people. One record from 1135 said the great stones were carried to England by giant magical creatures!

    In modern times Stonehenge has become a huge hit with tourists. When Stonehenge was first opened to the public it was possible to walk among and even climb on the stones, but the stones were circled with ropes in 1977 as a result of serious erosion(侵蚀). Visitors are no longer allowed to touch the stones, but are able to walk around from a short distance away. What's more, visitors can make special bookings to get into the stones throughout the year.

Economically speaking, are we better off than we were ten years ago? Twenty years ago?

In their thirst for evidence on this issue, commentators seized on the recent report by the Census Bureau, which found that average household income rose by 5.2% in 2015. Unfortunately, that conclusion puts too much weight on a useful, but flawed and incomplete, statistic. Among the more significant problems with the Census's measure are that: 1) it excludes taxes, transfers, and compensation like employer-provided health insurance; and 2) it is based on surveys rather than data. Even if precisely measured, income data exclude important determinants of economic wellbeing, such as the hours of work needed to earn that income.

While thinking about the question, we came across a recently published article by Charles Jones and Peter Klenow, which proposes an interesting new measure of economic welfare. While by no means perfect, it is considerably more comprehensive than average income, taking into account not only growth in consumption per person but also changes in working time, life expectancy, and inequality. Moreover, it can be used to assess economic performance both across countries and over time.

The Jones-Klenow method can be illustrated by a cross-country example. Suppose we want to compare the economic welfare of citizens of the U.S. and France in 2005.

In 2005, as the authors observe: real consumption per person in France was only 60% as high as the U.S., making it appear that Americans were economically much better off than the French on average. However, that comparison omits other relevant factors: leisure time, life expectancy, and economic inequality. The French take longer vacations and retire earlier, so typically work fewer hours; they enjoy a higher life expectancy, presumably reflecting advantages with respect to health care, diet, lifestyle, and the like; and income and consumption are somewhat more equally distributed there than in the U.S. Because of these differences, comparing France's consumption with the U.S.'s overstates the gap in economic welfare.

Similar calculations can be used to compare the U.S. and other countries. For example, this calculation puts economic welfare in the United Kingdom at 97 % of U.S. levels, but estimates Mexican well-being at 22%. The Jones-Klenow measure can also assess an economy's performance over time. According to this measure, as of the early-to-mid-2000s, the U.S. had the highest economic welfare of any large country. Since 2007, economic welfare in the U.S. has continued to improve. However, the pace of improvement has slowed markedly.

Methodologically, the lesson from the Jones-Klenow research is that economic welfare is multi-dimensional. Their approach is flexible enough that in principle other important quality-of-life changes could be incorporated—for example, decreases in total emissions of pollutants and declines in crime rates.