For many kids, the Internet is at their fingertips. From computers to smartphones, a web of information is open to them. According to a new report from the Pew Research Centre, about three out of four kids aged 12 to 15 connect the Internet using a mobile device from time to time. Many younger kids are online too.

Julian Zeitlinger, 9, from New Jersey, uses his computer to watch videos and play games. To keep him safe online, his parents monitor his web use and discuss Internet safety with him. “I ask my parents if something is wrong.” Julian says. Mobile devices offer more ways than ever to share personal information. The information can be dangerous in the wrong hands. A study found that 62% of children aged 8 to 17 have had an unpleasant online experience.

Have you ever had to enter a parent’s e-mail address when signing up for a website? That safety measure is there because of the Children’s Online Privacy Protection Act (COPPA). The law says sites for kids under 13 cannot collect personal information, such as a phone number or full name, without a parent’s permission.

This July, the Federal Trade Commission (FTC) will update COPPA for the first time since the law was created in 1998 when there were no smartphones. “The nature of the way kids get online has changed,” FTC lawyer Phyllis Marcus said. When the changes take effect, COPPA will apply to mobile devices and newer forms of advertising. It will expand what falls under “personal information” to include videos, photographs and services that give out users location.

COPPA doesn’t cover everything that can go wrong online. That’s why kids and parents need to know what to look out for and to stop and think before sharing information online.

“Many people now misunderstand that if a site is following. COPPA, it is totally safe,” says privacy expert Shai Samet. He runs KidSAFE, which checks if a site meets KidSAFE standards and is safe. “It’s important that kids know how useful the Internet is but that it can also be dangerous if you are not careful,” he adds.

For many environmentalists, the world seems to be getting worse. They have developed a hit-list of our main fears; that natural resources are running out; that the population is ever growing, leaving less and less to eat; and that the planet’s air and water are becoming ever more polluted.

However, a quick look at the facts shows a different picture. First, energy and other natural resources have become more abundant, not less so. Second, more food is now produced per head of the world’s population than at any time in history. And finally, most forms of environmental pollution appear to have been exaggerated. One form of pollution-the release of greenhouse gasses that causes global warming-does appear to be a phenomenon that is going to extend well into our future, but its total impact is unlikely to pose a devastating problem.

Yet opinion polls suggest that many people nurture the belief that environmental standards are declining and three factors seem to cause this disjunction between perception and reality.

One is the lopsidedness(不平衡) built into scientific research. Scientific funding goes mainly to areas with many problems. That may be wise policy, but it will also create an impression that many more potential problems exist than the real case.

Secondly, environmental groups need to be noticed by the mass media. They also need to keep the money rolling in. Understandably, perhaps, they sometimes overstate their arguments. In 1997, for example, the World Wide Fund for Nature issued a press release entitled: ‘Two thirds of the world’s forests lost forever’. The truth turns out to be nearer 20%.

A third source of confusion is the attitude of the media. People are clearly more curious about bad news than good. Newspapers and broadcasters are there to provide what the public wants. That, however, can lead to intensified misunderstanding. An example was America’s confronting with El Nino in 1997 and 1998. This climatic phenomenon was accused of damaging tourism, causing allergies, melting the ski-slopes and causing 22 deaths. However, according to an article in the Bulletin of the American Meteorological Society, the damage it did was estimated at US$4 billion but the benefits added up to some US$19 billion. These came from higher winter temperatures (which saved an estimated 850 lives and reduced heating costs).

If you think that running marathons will help you live a long and healthy life, new research may come as a shock. According to a recent scientific study, people who do a very strenuous workout are as likely to die as people who do no exercise at all.

Scientists in Denmark have been studying over 1,000 joggers and non­joggers for 12 years. The death rates from the sample group indicate that people who jog at a moderate pace two or three times a week for less than two and a half hours in total are least likely to die. The best speed to jog at was found to be about 5 miles per hour. The research suggests that people who jog more than three times a week or at higher speeds of over 7 mph die at the same rate as non­joggers. The scientists think that this is because strenuous exercise causes structural changes to the heart and arteries. Over time, this can cause serious injuries.

Peter Schnohr, a researcher in Copenhagen, said, “If your goal is to decrease risk of death and improve life expectancy, jogging a few times a week at a moderate pace is a good strategy. Anything more is just unnecessary, and it may be harmful.”

The implications of this are that moderate forms of exercise such as tai chi, yoga and brisk walking may be better for us than “iron man” events, triathlons and long­distance running and cycling. According to Jacob Louis Marott, another researcher involved in the study, “You don’t actually have to do that much to have a good impact on your health.And perhaps you shouldn’t actually do too much.”