In cities with rent control, the city government sets the maximum rent that a landlord (房东) can charge for an apartment. Supporters of rent control argue that it protects people who are living in apartment. Their rent cannot increase; therefore, they are not in danger of losing their homes. However, the critics say that after a long time, rent control may have negative effects. Landlords know that they cannot increase their profits. Therefore, they invest in other businesses where they can increase their profits. They do not invest in new buildings which would also be rent-controlled. As a result, new apartments are not built. Many people who need apartments cannot find any. According to the critics, the end result of rent control is a shortage of apartments in the city.

    Some experts argue that the minimum wage law can cause problems in the same way. The federal government sets the minimum that an employer must pay workers. The minimum helps people who generally look for unskilled, low-paying jobs. However, if the minimum is high, employers may hire fewer workers. They will replace workers with machinery. Therefore, other things being equal, the number of workers that employers want decreases. Thus, critics hold the opinion that an increase in the minimum wage may cause unemployment. Some poor people may find themselves without jobs instead of with jobs at the minimum wage.

    Supporters of the minimum wage say that it helps people keep their dignity. Because of the law, workers cannot sell their services for less than the minimum. Furthermore, employers cannot force workers to accept jobs at unfair wages.

    Economic theory predicts the results of economic decision, such as decisions about farm production, rent control, and the minimum wage. The predictions may be corrected only if “other things are equal”. Economists do not agree on some of the predictions. They also do not agree on the value of different decisions. Some economists support a particular decision while others criticize it. Economists do agree, however, that there are no simple answers to economic questions.

    A warm drink of milk before bed has long been the best choice for those wanting a good night's sleep. But now a study has found it really does help people nod off-if it is milked from a cow at night.

    Researchers have discovered that “night milk” contains more melatonin(褪黑激素), which has been proven to help people feel sleepy and reduce anxiety.

    The study, by researchers from Seoul, South Korea, involved mice being fed with dried milk powder made from cows milked both during the day and at night.

    Those given night milk, which contained 10 times the amount of melatonin, were less active and less anxious than those fed with the milk collected during daytime, according to the study published in The Journal of Medicinal Food.

    Night milk quickened the start of sleep and caused the mice to sleep longer.

    While the effect of cows milk harvested at different time has not been tested on humans up to now, taking melatonin drugs has been suggested to those who are struggling to fall asleep at night.

    Previous studies have also indicated that milk can be excellent for helping sleep because of the calcium content, which helps people to relax.

    Milk is also sugar-free and additive-free with nutritionists recommending skimmed milk as the best choice before bed as it is the least fattening. The more fat you take in before bedtime, the greater burden you will put on your body at night.

    What would it be like to walk on Mars? If you could build the highest building in the world，what would it look like? Do you dream of being the next J. K. Rowling? This summer, you can experience all of these things, and more. All you need is an Internet connection and your imagination.

    A recent study by the Kaiser Family Foundation found that kids spend an average of 1 hour and 29 minutes online each day. Many kids like to use that time to chat with friends, play games or check e­mails. But the next time you get on the Web, try exploring the world instead. “With the Internet，you can go back 11,000 years in time，or go 11,000 kilometers across the planet.” said Russell, Web search expert of Google. “The whole scope of history and the world is open to you.”

    There is a wealth of information to be found online. For example, if your family is going on vacation somewhere, do a quick online search on the area before you even get in the car. “What's the background of the place; what's the history？” says Russell. “I like to tell my kids, ‘Whenever you have a question, whenever you have a doubt, search it out.'”

    Ready to launch a virtual journey of your own? Here are a few starting points to get you thinking and to help you on your way. You can invite your parents along for the ride, too. Always ask for permission before downloading programs and software onto your computer. And check with a parent or an adult before visiting any new Web site.

    Navigate the world in 3­D with Google Earth. Begin in outer space and zoom (快速移动) into the streets of any city, from Hong Kong to San Francisco. Or visit ancient monuments, watch the changing rainforests over time, and dive underwater to explore tropical reef.

    With the Moon in Google Earth tool, you can walk in Neil Armstrong's famous footsteps. Take a guided tour of the moon's surface with Armstrong's fellow shuttle mate astronaut Buzz Aldrin.

    When you're exploring that part of the solar system, hop on over to the Red Planet with Google Mars. There, you can move very quickly around the surface and see images from the Mars Rovers.

    “He is the best choice for goodwill ambassador.” Indian movie fans in China say.

    Indian actor Aamir Khan has got his major celebrity status in China. Aamir Khan was in China last week to promote his latest Hindi film Secret Superstar. During his weeklong stay, first in Shanghai and then in Beijing, the Indian actor also found out that he has become a major celebrity in a country where Hollywood's reach has been traditionally limited.

    Some local analysts compare his star status in China to that of Hollywood actors Tom Hanks, Tom Cruise and Leonardo DiCaprio. Others wonder if Khan is an activist actor. Still others describe him as a feminist（女权主义者）. The Chinese media seem to have called him Mishu, or Uncle Aamir. The surprising rise in popularity of the 52-year-old Bollywood star is owing to his striking movies. At more than 1 million, Khan has the most followers as an Indian on Sina Weibo, the country's Twitter-like platform.

    Secret Superstar had made more than 400 million yuan（$63 million）earlier this week. The story of a teenage Muslim girl's fight against ugly patriarchy（父权制）to realize her dreams was released in China on Jan 19.

    Last year, his film Dangal, inspired by the real journey of an Indian wrestler through a conservative landscape to turn his daughters into world-class athletes, had made nearly 1.3 billion yuan.

    In 2011, Khan's work first got major attention from Chinese moviegoers with Three Idiots, which was released in India much earlier. A statement on India's orthodox education system, similar to that of China, the Hindi film went along with the local audience. Film critics and fans alike recommended it to their friends.

    Some film critics say the education systems, gender discrimination（性别歧视）and domestic violence（家庭暴力）that Secret Superstar shows are among similarities of social issues in India and China. A series of “masterpieces” have made Khan an effective brand in China, in addition to his movie marketing and film devotion.

    I'll never forget the day when Mary came into my office and said, I am too old to learn how to use a computer. I shook my head. Here was a woman who had raised 6 children and who had made great progress in her career telling me that she was too old to learn something new. I told her that I always believed people were never too old to learn.

    Mary followed my advice and did learn how to use the computer. Now, she is retired and leading a very active life volunteering in her community( 社区 ),using her computer skills and helping anyone that needs help.

    When she was in her sixties, one day she called me and said she had played the piano for others all her life, and now she was going to make a CD of her own. My mind flashed back to the day when she told me she was too old to learn. You can imagine my surprise and delight.

    To produce the CD, she had a lot of things to learn. It was not just sitting at the piano and playing. She had to research the songs, learn about copyright(版权),and learn about marketing. It was pretty amazing for someone who once said she was too old to learn. And finally she made it. Now she has her own CD-Mixed Blessings.

    Most of you probably have heard about some people who have gone back to university in their seventies and have also graduated. They are on their way again to charging themselves with a new skill and a new attitude towards life. The point is you are unable to learn anything at any age if you believe you are too old. On the contrary, you can achieve anything at any age if you believe you can.

All Aboard for a Family Trip by Train

    If you're looking for a family vacation idea, look no further. Explore America with Amtrak. On the train, your family will have plenty of room to spread out and relax.

    Once on board, the family can take in the scenery from the Sightseer Lounge（观景车厢）. Plus, most of our overnight trains feature Dining cars that serve three meals a day, with full menus and table service. If you're looking for lighter fare, grab a bite to eat or a drink in the Café car. You can also reserve Sleeping car accommodations and let the gentle rhythms of the train sway you to sleep. It's the best way to arrive at your destination rested and ready to go.

    Learn More about the Onboard Experience on www.amtrak.com

    A Dining Experience like No Other

    From full sit-down meals to more informal food service, many trains have one or more option for onboard dining. If you're not hungry, you might start to hear your stomach rumbling（腹鸣） after looking at our menus. We provide you with more dining choices, onboard dining reservations and the different types of dining cars, like long distance dinning car, lounge car and café car.

    Sleeping Accommodations

    Sleeping accommodations are available on most long-distance routes. Amtrak trains traveling on long-distance routes typically use either two-level Superliner or one-level Viewliner train car equipment, each of which include bedrooms arranged in various configurations and private and public bathrooms and showers.

    Seating Accommodations

    On most Amtrak trains, you have three options for seating accommodations. The availability of these options varies depending on your route and the type of train equipment in use:

    Coach Class: Designed for You to Relax.

    Business Class: More Amenities. More Comfort.

    First Class: Exclusively on Acela Express.