On Monday, the Centers for Disease Control and Prevention predicted that 42% of Americans could be overweight by 2030. Our expanding waistlines lead to not only a medical problem, but according to a recent article In The New York Times, it could also endanger personal safety in some situations—in an airplane crash, for example.

    The New York Times' Christen Negroni reports that engineers and scientists are questioning whether airplane seats are adequately constructed to protect overweight travelers. Government standards for airplane seat strength（强度）— first set moe than 60 years ago — require that the seats be made for a passenger weighing 170 pounds (77kg). Today, the average American man weighs nearly 194 pounds (88kg) and the average woman 165 pounds (75kg). Negroni reports:

    “If a heavier person completely fills seat, the seat is not likely to behave as intended during a crash,” said Robert Salazar, the leading scientist at the Center for Applied Biomechanics at the University of Virginia. “The energy absorption that is built into the aircraft seat is likely to be overpowered and the passengers will not be protected properly.”

    “Nor would the injury be limited to that passenger only,” Dr. Salzar said. “If a seat or a seat belt fails,” he said, “those people who are seated nearby could be endangered from 'the uncontrolled movements of the passenger'.”

    Most complaints about airplane seats focus on their lack of comfort and high ticket price, and whether overweight passengers should be made to buy two seats. But The New York Times' article brings up another reason to feel anxious about flying. Investigators of the issue got in touch with the airplane seat and seat belt makers, but they refused to comment on the problem. Experts agreed that crash testing should be done with overweight dummies （人体模型）. Both airplane seats and seat belts should be tested, they said.

    Fortunately, however, according to Nora Marshall, a senior adviser at the National Transportation Safety Board, the board's investigators have never seen an accident involving a commercial plane in which the weight of a passenger was a problem.

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    First opened to the public in 1976,the California State Railroad Museum is one of Sacramento's largest and most popular visitor destinations.Over 500,000 people visit the museum every year,with guests traveling from throughout the world to experience this world-famous place.

    The museum consists of six original buildings.The main exhibit building,the Railroad History Museum,totals 100,000 square feet.Completed at a cost of US $16.1 million,it opened in May 1981.

    Hours: The museum is open daily (except on Thanksgiving,Christmas and New Year's Day) from 10 a.m. to 5 p.m. From May 28 to September 3,the museum will be open until eight o'clock in the evening.

    Admission: US $10 for adults,US $5 for youths aged six to seventeen;Children aged five and under are free; Cash,personal checks,traveler's checks and credit cards are accepted for payment.

    Location: The California State Railroad Museum is located at the corner of Second and “I” street in Old Sacramento.

    Parking: A limited number of spaces are available for parking on the streets near the museum.However,these spaces are not suitable for guests visiting longer than 90 minutes.All-day parking is available in the large public garage at the “I” Street entrance to Old Sacramento,for a small fee.

    Food Service: Many restaurants are located near the museum.These range from reasonably priced, family-friendly places to some of the finest dining restaurants in the city.

    Accessibility: The museum is fully accessible to people with disabilities.Certain exhibits and programs have limited accessibility,due to factors such as narrow and historic stairways.

    Photography: We welcome photography for personal use.Hand-held cameras are allowed;however,tripods are not permitted for safety reasons.A Morning for Photographers at the museum is a special event.Tripods are allowed during this event.

    China is known for its long history, rich culture, and cute pandas. It's also known for some of the worst air quality in the world. But the Asian country is now using a natural weapon against air pollution – trees.

    In February, China's government announced plans to cover at least 32,400 square miles with forest. That is about the size of Ireland. Some 60,000 soldiers will take charge of the tree-planting program. Most of the trees will be planted in Hebei Province. That is an area surrounding China's capital, Beijing.

    Huang Wei is an environmentalist who works for Greenpeace East Asia. She is optimistic about the plan. “Trees act as a sink to absorb carbon dioxide and other pollutants,” she said. Carbon dioxide is a gas that traps the Earth's heat. It contributes to global warming.

    Why is China's air filled with harmful chemicals? It's because the country relies on coal-fired power plants. When coal is burned, PM2.5 is produced, PM2.5 is a pollutant. It can cause shortness of breath, heart attacks, and even death.

    Just two years ago, pollution levels were so high in Beijing that schools and factories had to close. Huang hopes China's tree-planting plan will reduce the nation's suffering from air pollution.

    The Chinese government is getting help from others in its drive to make the nation greener. Stefano Boeri is an Italian architect and urban planner. He is leading an effort to plant vertical（垂直的）forests in China.

    Boeri's designs have already taken root in the city of Nanjing, China. That's where the Nanjing Green Towers are under construction. The building has two towers. Thousands of trees and hanging plants will grow on the balconies and rooftops.

    Boeri says his goal is to design buildings that help the environment and improve air quality. He also hopes to encourage a new generation of green architects.

    Smoking is harmful. But as soon as you quit the habit, everything will be OK, right? Wrong.

    New research has found that even if you give up smoking, the damage it has done to your genes will stay there for a much longer time. In the research, a team of US scientists studied the blood of 16,000 people. Among them, some were smokers, some used to smoke, and the rest were non-smokers. Scientists compared their genes and found that more than 7,000 genes of smokers had changed--a number that is one-third of known human genes.

    According to NBC News, both heart disease and cancer are caused by genetic changes. Some people may have had the changes when they were born, but most people get them in their day-to-day lives while doing things like smoking.

    When you stop smoking, a lot of these genes will return to normal within five years.

This means your body is trying to heal (治愈) itself of the harmful effects of smoking. But the changes in some of the genes stay for longer. They can stay for as long as 30 years, It's almost like leaving a footprint on wet cement (水泥)—-it will always be there, even when you've walked away and when the cement becomes dry.

    Although the study results may make people unhappy, there is a bright side: the findings could help scientists invent medicine to treat genetic damage caused by smoking or find ways to tell which people have heart disease or cancer risks.

    A young woman sits alone in café sipping tea and reading a book. She pauses briefly to write in a nearby notepad before showing her words to a passing café waiter: "Where are the toilets please?" This is a familiar scene in Tokyo's so-called "silent cafes", where customers are not allowed to speak, and only communicate by writing in notepads.

    The concept rises by a desire to be alone among young Japanese, a situation brought by economic uncertainly, a shift in traditional family support structures and the growing social isolation. The phenomenon is not limited to coffee shops but covers everything from silent discos, where participants dance alone wearing wireless headphones connected to the DJ, to products such as small desk tents designed for conversation-free privacy in the office. One Kyoto company even offers single women the opportunity to have a "one woman wedding" – a full bridal affair, complete with white dress and ceremony, and the only thing missing is the groom. The trend has its own media expression – "botchi-zoku", referring to individuals who consciously choose to do things completely on their own.

    One recent weekday afternoon, Chihiro Higashikokubaru, a 23-year-old nurse, travelled 90 minutes from her home, to Tokyo on her day off in order to enjoy some solo time. Speaking quietly at the entrance of the café, Miss Higashikokubaru said: "I heard about this place via Twitter and I like the idea of coming here. I work as a nurse and it's always very busy. There are very few quiet places in Tokyo, and it's a big busy city. I just want to come and sit somewhere quietly on my own. I'm going to drink a cup of tea and maybe do some drawings. I like the idea of a quiet, calm atmosphere."

    The desire to be isolated is not a new concept in Japan, home to an estimated 3.6 million "hikikomori" – a more extreme example of social recluses（隐士）who withdraw completely from society.

    Children who qualify for free school meals are twice as likely to be out of work in later life as their better off peers, and even when they get good qualifications at school, the employment gap remains, as a research has found.

    A report by Impetus, a charity that supports young people from disadvantaged backgrounds, found that 26% of those on free school meals (FSM) were not in education, employment, or training (Neet) after leaving school. In contrast, only 13% of non-FSM children ended up Neet.

    The study found that young people from disadvantaged backgrounds were less likely to get good qualifications, but even when they had the same qualifications as their better-off peers, they were still 50% more likely to be out of education and employment as other young adults.

    The research is based on analysis of longitudinal education outcomes data from the Department for Education, which reveals the impact of having a disadvantaged background on life chances and connects pupils' school records with their employment.

    "Qualifications play a central role," the report said, "and it is well known that disadvantaged young people have worse qualification outcomes than their better-off peers." It added qualifications alone were not enough to explain the difference in Neet rates. "Disadvantaged young people are around 50% more likely to be Neet than their similarly qualified but better-off peers. This is true at all levels of qualifications and regardless of age. This means that half the gap in Neet rates can be explained by qualifications, but half cannot."

    The study also showed how where you grow up affects your life chances—it found that a disadvantaged young person in north-east England is 50% more likely to end up Neet than a disadvantaged young person in London.

    Andy Ratcliffe, the CEO of Impetus, said: "We are breaking a fundamental promise to young people in this country. We tell them that study hard, get your qualifications and good jobs will follow. For many young people this is true. But for young people from disadvantaged backgrounds it isn't. They are less likely to get those qualifications, and even when they do, less likely to benefit from them."