You're rushing to work and a man ahead of you falls down on the sidewalk. Do you stop to help? In a study of by-standers, it was found that some people keep on walking.

    "There is a tendency to decide that no action is needed," says a psychologist, "In order to take action, you have to work against them." Here are some common thoughts that stop you from helping.

    ●Why should I be the one? I'm probably not the most able person in this crowd. You might think someone older or with more medical knowledge should offer assistance.

    ●What if he doesn't really need my help? The fear of embarrassment is powerful; no one wants to risk looking foolish in front of others.

    ●No one else looks concerned. We can follow the people around us, but most people tend to hold back their emotions in public.

    "If you spot trouble and find yourself explaining inaction, force yourself to stop and evaluate the situation instead of walking on," says the psychologist. "Then retry to involve other people; you don't have to take on the entire responsibility of being helpful. Sometimes it's just a matter of turning to the person next to you and saying, 'It looks like we should do something.' Or asking someone if an ambulance has been called and, if not, to call for one. Once you take action, most people will follow you."

    The more hours young children spend in child care, the more likely they are to turn out aggressive and disobedient by the time they are in kindergarten, according to the largest study of child care and development ever conducted. Researchers said this correlation(相关性) held true regardless of whether the children came from rich or poor homes, were looked after by a relative or at a center, and whether they were girls or boys.

    What is uncertain, however, is whether the child care actually causes the problem or whether children likely to turn out aggressive happen to be those who spend more hours in child care. It also remains unclear whether reducing the amount of time in child care will reduce the risk that a child will turn into a mean person. What's more, quality child care is associated with increased skills in intellectual ability such as language and memory, leading some academics to suggest that child care turns out children who are "smart and naughty".

    The government-sponsored research, which has tracked more than 1,300 children at 10 sites across the country since 1991, is bound to cause the debate over child care again: How should people balance work and family? And how should parents, especially mothers, resolve the demands that are placed on them to be both breadwinners and supermoms?

    That debate was already on display at a new briefing yesterday, where researchers themselves had different opinions about the data and its implications（含义）. "There is a constant relationship between time in care and problem behavior, especially those involving aggression and behavior," said Jay Belsky of Birkbeck College in London, one of the lead investigators of the study who has previously annoyed women's groups because of his criticisms of child care. "On behalf of fathers or mothers?" interrupted Sarah Friedman, a developmental psychologist at the National Institute of Child Health and Human Development (NICHD) and one of the other lead scientists on the study. "On behalf of parents and families," responded Belsky.

    "NICHD is not willing to get into policy recommendations," said Friedman, contradicting her colleague. "There are other possibilities that can be entertained. Yes it is a quick solution—more hours in child care is associated with more problems. The easy solution is to cut the number of hours but that may have implications for the family that may not be beneficial for the development of the children in terms of economics." In an interview after the briefing, Friedman said that asking parents to work fewer hours and spend more time with their children usually meant a loss of family income, which adversely（不利地）affects children.

    Scientists said that the study was highly reliable. But the researchers said they had no whether the behavioral difficulties persisted as the children moved to higher grades.

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    The future of Australia's solar industry is looking bright after a record 3.5m panels(嵌板)were installed on rooftops last year, giving the equal output of a medium-sized coal-fired power station. The record 1,057 MW of capacity (产能) in small scale systems installed across the country broke the previous record set in 2012, figures from the Clean Energy Regulator showed on Tuesday.

    Australia's solar power prosperity could almost double capacity in a year, The data also revealed that the average system size has also doubled since then from three to six kilowatts as average prices continued to fall. A fully installed 5KW system costs an average of $5,930 in Australia, according to the energy broker Solar choice.net.au. Its records show that the price has roughly halved in many capital cities since 2012.

    The regulator's executive general manager, Mark Williamson, said there was increasing interest in renewals as a way to take control of electricity bills. But more importantly, he said it was also good news for reducing carbon emissions.

    “We are seeing a wide cross section of Australians—households, community centers, schools, and small businesses—receiving rewards under the small scale renewable energy scheme,” Williamson said, “Our data shows consumers are embracing renewable energy to take control of their electricity bills. ”

    In 2017, there was a 41% increase in installing renewable energy capacity across all states and territories compared to 2016. Queensland led the way with installed capacity at 295MW, with the Australian Capital Territory taking top place for the biggest annual increase by 57 %. “I he data collected by the Clean Energy Regulator in 2017 reflects the industry is going from strength to strength, It looks like 2018 will be another big year for the solar industry.”

    The total of installed capacity for last year is expected to rise to 1,070MW when all the data is collected. A large coal-fired power station such as Loyd Yang A in Victoria's Latrobe Valley has a capacity of 2, 200MW.

    Sooner or later, many families will face the situation of moving. The experience can be very bad for kids, who may not be a part of the decision to move and may not understand it. You can take steps to make the entire process (过程) easier for everyone.

    Many kids like to stay in familiar places. So as you consider a move, weigh the benefits (好处) of that change against the comfort that neighborhood, school, and social life give your kids. If your family has recently dealt with a big life change, such as death, you may want to put off a move to give your children time to accept the fact.

    The decision to move may be out of your hands, perhaps because of a new job or money problems. Even if you're not happy about the move, try to keep a positive (积极的) attitude to it. During the move, a parent's attitude can greatly influence kids.

    No matter what the results are, the most important way to prepare kids to move is to talk about it. Try to give your children as much information about the move as possible. You can ask kids to join in the planning such as house-hunting or the search for a new school. This can make the change feel less like it's being forced on them. If you're moving across town, try to take your children to visit the new house and the new neighborhood.

    A move can have many problems, but good things also come from this kind of change. Your family might grow closer and you may learn more about each other by going through it together.

    A California family drives a car that could help protect the environment. When Jon and Sandy go to the store or to their daughters' soccer games, they drive in high-tech style. They drive a $1 million, fuel-cell-powered car. It may be the world's most expensive car and one of the most environmentally friendly cars. The FCX is the first fuel-cell-powered car to be used by a family anywhere in the world. The FCX uses hydrogen and oxygen for fuel. Car makers have been working to develop vehicles that are better for the environment. They are developing cars that use fuel other than gasoline.

    And then what is fuel cell technology? Fuel cell technology works by changing the chemicals hydrogen and oxygen into water. This process produces electricity, and water vapor which comes out of the exhaust pipe. Most cars release dangerous gases such as carbon monoxide and carbon dioxide. Many scientists say these gases are major contributors to global warming. “The FCX is driven just like any other vehicle on the road, but without the gases which pollute the environment,” scientists say. Fuel cell technology has been around since the 1800s, but scientists have yet been to perfect it. They say it may take years before the technology is ready for widespread use. Another earth-friendly car is already on the market. Hybrid cars use both gasoline and an electric motor. They are becoming more popular with customers because they cut pollution and improve fuel efficiency.

    Researchers at the University of Chicago have trained an artificial intelligence system, to write fake reviews on Yelp, a website showing customers reviews on shopping or something else, and it's pretty hard to tell them apart from a human review.

    Their study, which will be presented at the ACM Conference on Computer and Communications Security in October, aimed to throw attention onto how easily these systems can write reviews like humans and how damaging they can become if they're not monitored properly.

    Since many small businesses rely on online reviews to help grow and keep their reputation, a future where someone—like a rival or angry customer—could crazily fill their page with negative reviews written by a machine is pretty worrying.

    And, according to the research team, the threat goes far beyond a bunch of fake reviews on Yelp. "In general the threat is bigger," Ben Y. Zhao, one of the authors of the study, said. "I think the threat towards society is large and it really misleads users and shakes our belief in what is real and what is not. I think that's going to be even unimaginable."

    To test how believable these reviews came across, the researchers invited 40 volunteers and had AI generate five fake reviews for 40 actual restaurants. The volunteers were asked how useful they thought the review was and whether or not they thought it was fake. The AI reviews ranked as "effectively indistinguishable" from real reviews，according to the study. Further, the fake reviews were given a 3.15 "usefulness" rating, compared to a 3.28 rating for human reviews.