One day, I received a call from a colleague. He was about to give a student a zero for his answer to a physical problem, while the student claimed a perfect score. I was elected as their arbiter（仲裁人）. I read the examination problem: “Show how it is possible to determine the height of a tall building with the aid of a barometer（气压计）. ”The student had answered; "Take the barometer to the top of the building, attach a long rope to it, lower it to the street, and then bring it up, measuring the length of the rope. The length of it is the height of the building.”

    The student had really answered the question completely, but the answer didn't confirm his competence in physics. I suggested the student try again. I gave him six minutes to answer the question, warning that the answer should show some knowledge of physics. Five minutes later, he said he had many answers and dashed off one, which read：“Take the barometer to the top of the building and lean over the edge of the roof. Drop the barometer, timing its fall with a stopwatch. Then, use the physical formula（公式）to calculate the height of the building.”

    At this point, my colleague had to accept it, and then the student made almost full marks. I couldn't help asking the student what the other answers were. He listed many others, and then added, "Probably the best is to take the barometer to the administrator and said to him, ‘Sir, here is a fine barometer. If you tell me the height of the building, I will give it to you.”,

    Then, I asked the student if he really did not know the conventional answer to this question. He admitted that he did, but said that he was fed up with high school and college instructors trying to teach him how to think.

    The name of the student was Bohr who later was famous all over the world. He won the Nobel Prize for Physics in 1922.

    Most nations have at least one type of food that people from other countries think is unusual or unacceptable to eat. In France, people eat horse meat and frog legs. In South Korea and parts of China, restaurants serve dog meat. And in Australia, it's common to cook kangaroo meat on the barbecue and use emu eggs to make pancakes.

    The kangaroo and emu are native to Australia. Both animals are important to the national image of Australia and appear on the Australian coat of arms. They're also central figures in the history of the native Australians. However, they still hunt these animals for their meat, fur and fat.

    Today, Australian people continue to eat these animals. One of the reasons people eat kangaroo meat is that it's high in protein and low in fat, so eating kangaroo is a good option for anyone on a diet. It's also cheaper to eat kangaroo meat than other red meats. Because of this, a lot of university students choose to buy kangaroo meat. BBC News also reported that Australian scientists believe that eating kangaroo meat is good for the environment— kangaroos have different digestive systems than cows and sheep, meaning they produce less methane, the second biggest contributor to global warming.

    While emu meat is high in iron and vitamin C, most people don't think it tastes good. For this reason, they prefer emu eggs. One egg is large enough to make seven omelettes (煎蛋). And while ifs illegal to collect emu eggs from the wild, they can be bought from emu farms. Rather than cracking the beautiful dark shell, it's better to dry it by putting a small hole at each end and blowing. Afterwards, you can even carve a design into the eggshell.

    The month of March was a milestone for supporters of renewable energy in the U.S. For the first time, wind and solar power accounted for more than 10% of the country's electricity—up from less than 1% at the turn of the century. And total wind and solar power-plant capacity(发电量) is expected to grow more than 30% over the course of this year and next, according to the Energy Information Administration.

    Such forecasts have led many scientists and policymakers to think that moving a large part of the nation's power supply to renewable sources—as cities from Miami Beach to Salt Lake City have promised to do—may not be as far-fetched as once thought. But like any debate, there are dissenters, including those inside the federal government. Their argument is that the nation demands an uninterrupted supply of electricity and cannot count on sun, wind and natural gas to provide it. “You need solid hydrocarbons(固体碳氢化合物) on-site for rising peak demand,” Environmental Protection Agency administrator Scott Pruitt said on Fox Business in May, referring to the importance of coal as a power source.

    Many experts say the government's concern fails to account for how the power grid(电网) has improved in recent decades. Utility companies(公共事业公司) have developed innovative ways to move electricity from place to place to account for variation in weather. Battery technology can store power for use when renewable sources cannot operate, meaning solar power can be used on days when the sun doesn't shine. And the nation's vast supply of natural gas can be turned into usable energy with the flick of a switch.

    “I don't think 5 or 10 years ago I'd be comfortable telling you we could not sacrifice reliability when we're going to have 35% of our energy come from wind,” said Ben Fowke, CEO of the utility company Xcel Energy, at a recent conference. “I'm telling you, I'm very comfortable with that today.”

    Indeed, many parts of the country are already close to that reality. In some regions, like Iowa and Kansas, renewable energy supplies more than 25% of the electricity. The market has shifted so far in favor of natural gas and renewable energy that even the most concerted federal effort is unlikely to stop its growth. Any attempt to slow the growth of wind and solar will face strong pushback. “If anyone wants to do away with it,” Republican Senator Chuck Grassley told Yahoo News of the federal government's potential cuts to wind energy, “he'll do it over my dead body.”

    But the federal government could slow the acceleration—and with billions of dollars in private and public investments at risk, the pace of change matters. Decisions made today will shape the future of the nation's energy grid for decades to come.

    People with an impulsive(冲动的) personality refer to those who tend to do things without considering the possible dangers or problems first. According to a new study by researchers at the University of Georgia, such people may be more likely to have food addiction. The study found that people exhibiting impulsive behavior weren't necessarily overweight, but impulsiveness was related to a direct relationship with food, and therefore, less healthy weight.

    Food addiction has been compared to addictive drug use. Studies have linked the dopamine (多巴胺) release that occurs after tasting delicious food to the dopamine release that happens when people consume other addictive substances.

    Impulsive behavior involves several personality traits (特点). Two of these traits, known as negative urgency and lack of perseverance, were particularly associated with food addiction and high BMI (身体质量指数) during the study.

    Negative urgency is characterized by the tendency to behave impulsively when experiencing negative emotions. Some people might drink alcohol or take drugs. For others, it could mean eating to feel better. Lack of perseverance is when a person has a hard time finishing hard or boring tasks. People with a lack of perseverance might have difficulty attempting to change addictive eating behavior, which could also cause obesity.

    "Impulsiveness might be one reason why some people eat in an addictive way despite motivation to lose weight," said Dr. Ashley Gearhardt, a clinical psychologist. He was involved in developing the Yale Food Addiction Scale in aid of those people. "We are theorizing that if food addiction is really a thing, then our measure, the Yale Food Addiction Scale, should be related to helping control impulsive action," said Gearhardt.

    Clinical psychologist Dr. James MacKillop, whose lab was conducting the study, believes that therapies(治疗，疗法)used to treat addictive drug behavior could help people who suffer from addictive eating habits.

    "Most of the programs for weight loss at this point focus on the most obvious things, which are clearly diet and exercise," MacKillop said. "It seems that managing strong desires to eat would naturally fit in with the skills a person would need to eat healthily."

    Traditional Chinese Medicine (TCM) needs to prove its worth through rigorous clinical trials, according to the head of one of China's largest herbal remedy companies, as a contentious new law to boost the $40bn sector comes into effect.

    Traditional Chinese Medicine is estimated by analysts to account for a third of sales in China's $117bn pharmaceutical (药学) market, the world's second largest. But most of those sales are of relatively cheap over-the-counter drugs, with many Chinese hospital doctors unwilling to prescribe TCM remedies because of the lack of evidence for their effectiveness.

    China's first law promising equal status for TCM and western medicine in the country's state-dominated healthcare system comes into effect this weekend. Provisions include encouragement for hospitals to set up TCM centres, and a licensing system for practitioners (从业者). "This law is very important for securing the status of TCM," said Wu Yiling, chairman of Yiling Pharmaceutical, a company that makes herbal remedies based on traditional recipes in the northern province of Hebei.

    Listed in Shenzhen, Wu Yiling has a market capitalization of RMB 20.7bn ($3bn). Mr Wu, the son of a herbal practitioner, controls a family fortune of $1.6bn, according to the Hurun Rich List.

    Mr Wu is both a supporter of the nature of Qi—the mystical energy force that provides the basis for much of TCM theory—and the clinical trials vital to western pharmaceutical companies. "TCM needs to develop using modern research methods," he said.

    For instance, researchers from Peking and Cardiff Universities tested the health benefits of Yiling's herbal medicine Yangzheng Xiaoji, publishing papers in the International Journal of Oncology that showed the drug can slow the growth of cancer tumours. "The theory and recipe is TCM, but in practice the evaluation of our medicines is carried out according to western evidence-based methods," Mr Wu said.

    Analysts say such tests can help gain support from doubtful hospital doctors and boost prescriptions. "Doctors need strong evidence that drugs definitely work," said Serena Shao, healthcare analyst at brokerage CLSA. "Some of these companies are currently doing clinical trials, and getting proof that their drugs have the same efficacy (功效) as chemical drugs. That's the way to go." she added.

    The TCM law has been greeted with doubt from China's western-schooled medical establishment, which points to a lack of rigorous training for TCM doctors, and a recent series of shocking events involving herbal injections believed to have been harmful. "Officials will try and encourage TCM, but also will be very cautious about what kinds of TCM they use in hospitals," added Ms Shao.

    I never saw my father home from work late or ill, nor did I ever see my father take a "night out with the boys". He had no hobbies but just took care of his family.

    For 22 years, since I left home for college, my father called me every Sunday at 9:00 am. He was always interested in my life—how my family was doing. The calls even came when he and my mother were in Australia, England or Florida.

    Nine years ago when I bought me first house, my father, 67 years old, spent eight hours a day for three days, painting my house. He would not allow me to pay someone to have it done. All he asked was a glass of iced tea, and that I hold a paintbrush for him and talk to him. But I was too busy, for I had a law practice to run, and I could not take the time to hold the paintbrush, or talk to my father.

    Five years ago, my 71-year-old father spent five hours putting together a swing set (秋千) for my daughter. Again, all he asked was that I get him a glass of iced tea, and talk to him. But again, I had laundry to do, and the house to clean.

    The morning on Sunday, January 16, 1995, my father telephoned me as usual, this time he had seemed to have forgotten some things we had discussed the week before. I had to get to church, and I cut the conversation short.

    The call came at 4:40 am. That day my father was sent to hospital in Florida. I got on a plane immediately, and I vowed (发誓) that when I arrived, I would make up for the lost time, and have a nice long talk with him and really get to know him.

    I arrived in Florida at 1:00 am, but my father had passed away at 9:12 pm. This time it was he who did not have time to talk, or time to wait for me.

    In the years since his death I have learnt much about my father, and even more about every single day.