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.

    Housework is a frequent source of disputes (争论) between lazy husbands and their hard-working wives, but women have been warned not to expect men to pull their weight any time soon.

    A study from Oxford University has found that men are unlikely to be doing an equal share of housework before 2050. Mothers, the researchers warned, will continue to shoulder the burden of childcare and housework for the next four decades, largely because housework such as cleaning and cooking is still regarded as “women's work”.

    The gap between the amount of time men and women spend on housework has narrowed slowly over the past 40 years. But it will take another four decades before true housework equality (平等) is achieved, the study concluded.

    The research found that in the Nordic countries, the burden of housework is shared more equally between men and women. In the UK, women spend an average of four hours and forty minutes each day on housework, compared with two hours and twenty-eight minutes for men. This is an improvement from the 1960s, when British women typically spent six hours a day on housework, while men spent just 90 minutes every day.

    But progress towards housework equality appears to be slowing in some countries. Dr Oriel Sullivan, a research reader from Oxford's Department of Sociology, said, “we've looked at what is affecting the equality in the home, and we have found that certain tasks seem to be given according to whether they are viewed as ‘men's work' or ‘women's work'.”

    Dr Sullivan said cultural attitudes taught at school may be responsible for the views of housework. “At school it is much easier for a girl to be a tomboy, but it is much more difficult for a boy to enjoy baking and dancing,” she said.

My dad was in the Air Force. When I was a kid, we moved every few years. That meant a lot of good-byes. It also meant getting used to a whole new community and a whole new school each time we moved. I can still feel what it was like to have to walk into the new school—that sinking feeling in my belly, that heaviness in my throat. It would always take time for me to learn how everything worked, what was cool and what not. It was always a struggle to find where I could fit in.

    Already shy, I didn't have much self-confidence in my friend-making abilities. I was the girl walking in the halls with her head down, panicking. When I spoke, you could hardly hear my soft voice. I was nervous and doubted myself a lot.

    It was very hard not having a history with everyone else. I was an outsider. But what I did have was soccer. Wherever I went, I knew that I could fit it with the soccer ball. The soccer team meant a familiar place and immediate friends for me. I could express myself and feel good about myself on the field. Playing hard helped to get rid of all my nervousness.

    Throughout our lives, our self-respect goes down when we feel like a failure, and it goes up when we feel successful. Doing something well, being praised, and feeling loved goes a long way. We all need to explore opportunities where we can be good at something and feel good about ourselves. Physical activity and sport participation is a terrific way to build up our sense of self-confidence and self-worth.

    A British friend told me he couldn't understand why Chinese people love eating sunflower seeds as a snack so much. “I've met a lot of older Chinese and many have a crack in their front teeth; I believe that's from cracking the seeds, ” he said.

    I had never noticed the habit, but once he mentioned it, I suddenly became more aware. I realized that whenever I'm watching TV or typing a report, I always start mindlessly cracking sunflower seeds. My friend doesn't like sunflower seeds, and, to him, it seems unnecessary to work so much just to get one small seed.

    When we were young, the whole family would usually get together for Chinese New Year. Then, we all lived close to one another, usually in a small city, and sometimes even neighbors would go door-to-door on Chinese New Year's Eve to check out what every household was making.

    I remember my parents would be in the kitchen cooking. Out in the living room , a large table would already be laid out, complete with fancy tablecloth, ready-made dumpling fillings, and dishes full of candy, fruits and sunflower seeds. Some of the dishes were to be offered to our ancestors later, while others were for neighbors and children to eat before the evening feast. I must have learned how to crack sunflower seeds back then.

    I don't think it's right to criticize one's choice in food or eating habits, no matter how strange they may seem.

    It's not only in China. When I went abroad, I found people had all sorts of strange habits when it came to food. In Denmark, they put salted red fish on bread and eat it for dinner, no matter how much it ruins your breath. They think it's a delicacy, and it's connected to their culture. I think it's a wonderful tradition.

    More primary care doctors in a community (社区)appear to lead to improved life expectancy for people living there, though a lack of such physicians across U.S. could be a cause of concern for overall population health in years to come.

    For the study, researchers looked at physician counts per 100,000 people in a range covering 2005 to 2015 in the U. S., along with life expectancy and specific causes of death. They found that an increase of 10 primary care physicians per 100,000 population was associated with a 51. 5-day increase in life expectancy, while an increase of 10 specialty physicians per 100, 000 population increased life expectancy by 19. 2 days. An increase in primary care physicians also was associated with reductions of many deaths including heart diseases and cancers.

    Along with those findings, though, the study said many communities did not have primary care physicians in 2015, with the decline in supply more prominent in rural areas than their urban areas. Many believe that a well-functioning health care system requires a solid foundation of primary care, however, payment difference between primary care and technical specialties continue to dispirit the U. S. primary care physician workforce.

    "Higher pay and lifestyle preferences lead most students to choose non-primary care fields, even when their hearts say primary care," the study said. "We must turn this trend around with practical changes in physician payment policy; no amount of superb primary care training or creative practice reform will prevent further declines in primary care physician, which will lead to worsening health for the United States."

    The study's researchers conclude that future research should focus on the "quality and cover of primary care, types of primary care physician training and service offerings, and effective access rather than just supply".

    Sweet potato plants don't have spines or poisons to defend themselves. But some have evolved a clever way to let hungry herbivores (食草动物) know they aren't an all-you-can-eat buffet, a new study finds. When one leaf injured, it produces a chemical that warms the rest of the plant and its neighbors to make themselves inedible (不宜食用的)to bugs. Sweet potato breeders could potentially engineer plants to produce the chemical as an all-natural pest defense.

    Plant ecologists led by Axel Mithofer of the Max Planck Institute for Chemical Ecology in Jena, Germany, started to look into sweet potato (Ipomoea batatas) defenses after they noticed something interesting about two varieties of the plant grown in Taiwan: The yellow-skinned, yellow-fleshed Tainong 57 is generally herbivore-resistant, but its darker orange cousin, Tainong 66, is plagued (造成麻烦) by insect pests.

    To find out why, the team offered up Tainong 57 and 66 plants to hungry African cotton leafworm caterpillars (毛虫).Both plants released at least 40 airborne compounds as the caterpillars snacked on their leaves. But Tainong 57 produced a lot more of a chemical called DMNT, which has a very distinct smell, the team details this month in Scientific Reports. ("The smell is not nice," Mithofer says. "You wouldn't want it as a perfume.")

    DMNT isn't a new compound; researchers have isolated (分离出) the smelly chemical from other plants such as corn and cabbage, and it is known to induce defense responses in some species.

    To determine whether this was happening in sweet potatoes, scientists set up two experiments. First, they put two plants next to each other and wounded one so it produced DMNT. Then, they exposed healthy Tainong 57 plants to DMNT they had synthesized (合成).In both cases, the DMNT caused the exposed plants to produce more of a protein called sporamin in their leaves. (Tainong 66 did not have the same reaction.) When the caterpillar's snack on sporamin, "they immediately stop eating because they don't feel well," Mithofer says.

    Sporamin is the main protein in sweet potato tubers (块茎),and is indigestible raw, which is why sweet potatoes must be cooked for humans to enjoy them. "If the caterpillars could cook it, they could eat it," Mithofer says. Theoretically, he says, sweet potato breeders could use genetic engineering to make different varieties of sweet potato produce as much DMNT as Tainong 57, and display the same defense responses.

    Still, the research isn't ready for prime time, cautions plant ecologist Martin Heil. DMNT might work in the lab, but in the field, airborne chemicals can be "blown away in seconds," says Heil, who studies plant-insect interactions at the National Polytechnic Institute in Irapuato, Mexico.

    Mithofer himself has no plans now to create genetically engineered sweet potato plants, because they would not be a viable (能活下去的) crop in Europe, where genetically modified crops are outlawed. So for now, Tainong 66 will have to put up with being a caterpillar salad bar.