Traveling by bicycle is a very popular means of transportation throughout China. China has a huge population, and it is said that there is at least one bicycle for every two people within the country. Of course, many people in China ride bicycles purely for sport or exercise, but it's also a much more commonly accepted means of everyday transportation, as compared to countries such as the United States.

    If you are living for a long period of time in China, chances are you will want to purchase your own bicycle so that you can use it whenever you want for transportation or just for the enjoyment of riding. Even if you don't use a bicycle for everyday transportation, owning one can be a great way of enjoying some of the trails in the rural areas, just for fun. However, if you are just visiting China, renting a bicycle can be a more convenient choice.

    It is important to choose the correct bicycle for your use. You'll find that in China, the one-speed style of bicycle is extremely popular. These bicycles are great if you want to ride around in the city to see the sights. They are quite comfortable and easy to ride. You can often rent a bicycle for an entire day for around $15.

    However, if you wish to ride on some of the rural paths, a mountain bike style would be a better choice. They are great for different kinds of road surfaces, providing for a safer ride. If you are planning to have a desire to tour and still be able to carry packages with you, then a touring bike would be the best choice. These are generally the most expensive to rent, but are extremely handy for carrying packages and even some of your luggage along with you.

    I know what you're thinking: pizza? For breakfast? But the truth is that you can have last night's leftovers in the a. m. if you want to.

    I know lots of women who skip breakfast, and they have a ton of different excuses for doing it. Some say they don't have time, others think they're “saving” calories, still others just don't like breakfast food.

    But the bottom line is that eating in the morning is very important when you're trying to lose weight. “Eating just about anything from 300 to 400 calories would be better than nothing at all,” says Katherine Brooking, R., D., who developed the super-easy eating plan for this year's “SELF CHALLENGE”. And even pizza can be healthy if it's loaded with vegetables, and you stick to one small piece.

    Breakfast is one meal I never miss, and the same goes for most weight loss success stories. Research shows that eating breakfast keeps you from overeating later in the day. Researchers at the University of Southern California found that breakfast skippers have a bigger chance of gaining weight than those who regularly have a morning meal.

So eat something in the morning, anything. I know plenty of friends who end up having no breakfast at all, and have just coffee or orange juice. I say, try heating up last night's leftovers—it may sound crazy, but if it works for you, do it! I find if I tell myself, “You can always eat it tomorrow,” I put away the leftovers instead of eating more that night. Try it…you may save yourself some pre-bedtime calories. And watch your body gain the fat-burning effects.

    A new argument has been put forward as to whether penguins are disturbed by the presence of tourists in Antarctica.

    Previous research by scientists from Keil University in Germany monitored Adelie penguins and noted that the birds' heart rates increased dramatically at the sight of a human as far as 30 meters away. But new research using an artificial egg, which is equipped to measure heart rates, disputes this. Scientists from the Scott Polar Research Institute at Cambridge say that a slow moving human who does not approach the nest too closely, is not viewed as a threat by penguins.

    The earlier findings have been used to partly explain the 20 per cent drop in populations of certain types of penguins near tourist sites. However, tour operators have continued to insist that their activities do not adversely（不利地）affect wildlife in Antarctica, saying they encourage non-destructive behavior in tourists, and that the decline in penguin numbers is caused by other factors.

    Amanda Nimon of the Scott Polar Research Institute spent three southern hemisphere summers at Cuverville Island in Antarctica studying penguin behavior towards humans. “A nesting penguin will react very differently to a person rapidly and closely approaching the nest,” says Nimon. “First they exhibit large and prolonged heart rate changes and then they often flee the nest leaving it open for predators（掠夺者）to fly in and remove eggs or chicks.” The artificial egg, specially for the project, monitored both the parent who had been 'disturbed' when the egg was placed in the nest and the other parent as they both took it in turns to guard the nest.

    However, Boris Culik, who monitored the Adelie penguins, believes that Nimon's findings do not prove his own research invalid. He points out that species behave differently – and Nimon's work was with Gentoo penguins. Nimon and her colleagues believe that Culik's research was methodologically（方法论上）defective because the monitoring of penguins' responses needed catching the birds and fitting them with heart-rate transmitters（发射器）. Therefore, argues Nimon, it would not be surprising if they became stressed on seeing a human subsequently.

    In an unmanned supermarket, a customer waits to pay. With the use of advanced digital payment technology, including biological recognition and in-depth learning, the man leaves in a minute. There's no cashier in the store. At a large university, students use a hand-scanning machine that authorizes their entry into the gym. Those people are using "smart machines" which identify people by their physical characteristics. These new devices use fingers, hands, faces, eyes and voices. Some machines may even use smells. This new technology, called biometrics, gets information from parts of the body.

    In the past, biometric machines were used mainly in government agencies or in prisons. But now that the cost of the technology is lower, these machines are starting to be used everywhere, from border services to schools.

    Some people, however, are concerned that these machines will mean the destruction of personal privacy. They worry that the machines will get personal information about them, know it seems like these machines are invading our privacy, but actually, biometric machines help to protect it," says Jay Tarkett, who works at a company that develops the machines, "They can be used instead of passwords on a computer, for example. They can also identify criminals at airports. So, really, they help to promote public safety, and all the information stored is kept confidential by the machine itself."

    Some people don't like the idea of using fingerprints because they associate them with criminals, and feel like they are being accused of something, In addition, they don't work for some people, such as bricklayers, who wear down their fingerprints. Yet, face recognition does work well because the subject doesn't really have to do anything, To cash a check at a bank, for example, the customer has to do nothing more than look at a machine similar to an automatic teller. If the face matches the picture kept on file, the customer gets the money with no problems, The need to carry identification with you from place to place, then, would all but cease. It has been found that the hand scan works well ill the college gym. Before this machine was used, students at the college entered the gym using cards similar to credit cards. The problem was that students often lost or forgot their cards. With the hand-scanning machine, however, the problem was solved right away.

    But the machines are still new, and there can be problems. For example, voice recognition works on the phone, but it is not precise, and can be tricked. Another constraint(限制)we notice；, with machines that use face recognition in particular, is that they can be fooled if people color their hair or gain a lot of weight. However, this particular problem may be solved by a new type of technology that scans a person's iris, the colored part of the eye. It can even identify the person from a few feet away, recognizing a customer as he or she approaches the ATM.

    The popular wisdom for years has been that drinking in moderation (适度)—that's one “standard” drink a day for women and two for men-is linked to a lower risk of cardiovascular (心血管的) disease. But recent studies are casting some doubt on that long-held learning. Science now says it depends on your age and drinking habits.

    A 2017 study of nearly 2 million British with no cardiovascular risk found that there was still a modest benefit in moderate drinking, especially for women over 55 who drank five drinks a week. Why that age? Alcohol can influence the substance in the blood in positive ways, experts say, and that's about the age when heart problems begin to occur.

    Also, a 2018 study found that drinking more than 100 grams of alcohol per week—equal to roughly seven standard drinks in the United States or five to six glasses of wine in the UK—increases your risk of death from all causes and in turn lowers your life expectancy. Links were found with different forms of cardiovascular disease, with people who drank more than 100 grams per week having a higher risk of stroke, heart failure.

    Another 2018 study found that consistently drinking a moderate amount of alcohol, within recommended guidelines, had a protective effect on the heart over time. Unstable drinking habits were associated with a higher risk of heart disease, which the authors reflected might indicate broader lifestyle changes, such as poor health or stress. Former drinkers were also at greater risk.

    Overall, however, the latest thinking is that any heart benefit may be outweighed by other health risks, such as high blood pressure, certain cancers and liver damage.

Women who drink are at a higher risk for breast cancer; alcohol contributes about 6% of the overall risk, possibly because it raises certain dangerous hormones in the blood. Drinking can also increase the chance you might develop liver, mouth and oral cancers. One potential reason: Alcohol weakens our immune systems, making us more likely to inflame (发炎)—a driving force behind cancer.

    Put an ice cube from your fridge into a glass of water. You have a piece of string (线) 10 centimeters long. The problem is to take out that piece of ice with the help of the string. But you must not touch the ice with your fingers.

    You may ask your friends to try to do that when you are having dinner together. There is a saltcellar on the table. You must use salt when you carry out this experiment.

    First you put the string across the piece of ice. Then put some salt on the ice. Salt makes ice melt (融化). The ice round the string will begin to melt. But when it melts, it will lose heat. The cold ice cube will make the salt water freeze again.

    After a minute or two you may raise the piece of string and with it you will raise your piece of ice!

    This experiment can be very useful to you. If, for example, there is ice near the door of your house, you must use very much salt to melt all the ice. If you don't put enough salt, the water will freeze again.