Social change is more likely to occur in societies where there is a mixture of different kinds of people than in societies where people are similar in many ways. The simple reason for this is that there are more different ways of looking at things present in the first kind of society. There are more ideas, more disagreements in interest, and more groups and organizations with different beliefs. In addition, there is usually a greater worldly interest and greater tolerance in mixed societies. All these factors tend to promote social change by opening more areas of life to decision. In a society where people are quite similar in many ways, there are fewer occasions for people to see the need or the opportunity for change because everything seems to be the same. And although conditions may not be satisfactory, they are at least conventional and generally agreed.

    Within a society, social change is also likely to occur more frequently and more readily in the material aspects of the culture than in the non-material, for example, in technology rather than in values; in what has been learned later in life rather than what was learned early; in the less basic and less emotional aspects of society-than in their opposites; in the simple elements rather than in the complex ones; in form rather than in substance; and in elements that are acceptable to the culture rather than in strange elements.

    Furthermore, social change is easier if it is gradual. This is one reason why change has not come more quickly to Black Americans as compared to other American minorities, because of the sharp difference in appearance between them and white people.

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    Early birds-people who feel most energetic in the morning-tend to make healthier food choices throughout the day than night owls(夜猫子) , according to a new study.

    "Evening types had more irregular meal times," notes study author Mirkka Maukonen, studying human nutrition and obesity(肥胖) in Finland.

    Her study focused on people's risk of heart disease and their eating habits. Participants described when and what they had eaten during the past two days.

Maukonen's team then looked at l,854 people's lifestyle. After analyzing the data, the researchers found that both morning and evening people consumed approximately the same number of calories over a whole day.  However, night owls tended to eat their meals later than early birds. Before 10:00 am, night owls consumed less food than early birds. More of their calories came from sugar. After 8:00 pm, the night owls ate more sugar and fat. Meanwhile ,early birds ate more protein during both the morning and the evening hours.

    "Night owls tend to be less healthy than early risers," notes Courtney Peterson who studies diet and meal timing. "They are more likely to get heart disease or cancer. The fact that night owls tend to eat more junk food probably plays a role," Peterson says. "Other factors(因素) also can ruin a night owl's health. Night owls generally sleep worse," says Peterson. "Poor sleep has been linked to unhealthy food choices. "

    Peterson and Maukonen say night owls tend to have poor eating habits. But that doesn't necessarily mean that being a night owl makes a person a poor eater. It could be the reverse- eating poorly could affect people's sleep habits.

"The new findings should serve as a wake-up call to night owls. For them, the new results should encourage paying attention to healthier lifestyle choices," says Maukonen. 28. How did Maukonen do research about people's risk of heart disease?

    If you're showering every day, you're probably over doing it. In fact, showering too often can actually hurt your body in the long run.

    As Time's public health column explains, daily showers are common due to social norms more than any proper health need. We connect being freshly showered with being attractive and pleasing, so we tend to showering often to feel better.

    But what's the ideal shower frequency? In terms of your health — not how you look or smell — probably once or twice a week, assistant professor of dermatology at George Washington University, Dr. C. Brandon Mitchell says. “Your body is naturally a well-oiled machine,” he says. “A daily shower isn't necessary.”

    Of course, your situation may vary. If you have a job like car maintenance or construction, you'll obviously have a visible layer of dirt you'll need to wash off every single day. Similarly, if you work out every day, you may not have any health risks by washing every day, but you'll still be smelly. If you feel like you need to take daily showers for aesthetic（审美的）reasons, at least make most of them light showers. “I tell patients who shower daily not to soap their whole bodies,” Mitchell says. Hit your pits, butt and groin, which are the areas that produce strong smells. The rest of your body doesn't need much soaping, he says.

    Too much time spent under the hot water can dry out your skin, cause cracks（裂纹）that can lead to infections or germs getting into your skin, and take away the natural oils on your skin that help keep it healthy. So, even if you're aiming to be your most presentable, be sure to keep it moderate to avoid hurting your skin in the long run.

    As the Chinese Mid-Autumn Festival approaches, mooncakes are turning up all over China, from traditional teashops to Starbucks counters. The holiday is one of China's four most important festivals, and in the weeks before the date arrives, top hotels get into the spirit with lavish(奢华) treats in lovely packaging. Traditionally, the cookie-sized round pastry(馅饼) has a rich thick filling usually made from red-bean or lotus-seed paste and covered by a thin crust. It may also contain yolks from salted duck eggs, integrating a beautiful savory tinge into the sugary taste. Fillings and crusts have become more diverse over time, especially in the hands of skilled pastry chefs. The mooncakes in Chinese culture represent homesickness, and the top crust of each moon-shaped pastry is generally imprinted with the Chinese characters for longevity or harmony.

    This year, the fancy gift boxes that have long driven the mooncake trade are particularly striking and rich with tradition.

    For example, the Fairmont Peace Hotel in Shanghai, built in 1929 and a magnet for Hollywood celebrities in the 1930s, has prepared a selection of mooncake gift boxes with designs inspired by the beauty and elegance of the hotel's famous art deco style. The simplest box of four pieces (red-bean paste, creamy custard, plain cheese, green-bean paste) is 198 yuan($29.64), while more lavish selections of five or six pieces, including mooncakes with egg yolk, run up to 338 yuan for a box.

    Beijing's Nuo Hotel, meanwhile, has created Ming Dynasty (1368－1644) inspired mooncake gift packs based on the design of porcelain vases in the hotel lobby, with the essence of landscape painting using Zhang Dai's poetic passages to show the peaceful harmony of man and nature. The box of six is 158 yuan, and includes mooncakes ranging from cheese mango to charcoal burning fragrant Pu'er tea and white lotus with egg yolk. A box of eight cakes of different flavors is 228 yuan.

    People can't see you when you're speaking on the phone, but they can hear you. So, the way you speak is especially important. In fact, researchers have calculated that 80% of communication over the phone is through your tone of voice; and only 20% is from the words you use. Here are our top tips on how to speak over the phone.

    ①Facial Expressions

    Your facial expression can influence your voice. For example, if you smile, your voice will sound warm and friendly, just the opposite, if you have an angry look on your face, it can make you sound unpleasant.

    ②Volume

    If you speak too loudly, you could sound angry. And if you speak too softly, it'll be difficult to hear you. So, speak loudly enough to be heard clearly, but not so loud that you're shouting.

    ③Pace

    The pace of your voice is how quickly you speak. And this can show how you feel. For example, an angry person might speak faster than normal. Or a downhearted person might speak very slowly. Try speaking a little more slowly than normal. This will make you sound confident, and it'll make it easier for the other person to understand you.

    ④Gestures

    Gesturing can influence the tone of your voice. When you gesture, you bring more air into the lungs, which can make your voice sound warmer. Gestures are also useful to help you stress the right words or even find the words you need. The best thing about gesturing during a phone call is that no one can see what you're doing, so you can gesture as wildly as you like!

    ⑤Movement

    If you're feeling nervous, stand up and move around. It will reduce the nervousness in your body and help your voice to sound more confident.

    ⑥Pauses (停顿)

    Using pauses every now and then can help you to slow down. This will make you sound more confident and in control. Also, if you pause after giving some new information, it'll give the other person time to understand it. At the same time, listen to how the other person uses pauses. They could tell you something about the speaker's feeling. For example, when a speaker is really angry, he might use pauses and says, "I…am…so…angry…"

    A ten-year-old boy from Howell, Michigan is being praised as a hero thanks to his persistence (坚持) that led to saving the life of an elderly neighbor. The event happened late in an evening when Danny DiPietro was being driven home from hockey practice by his mom.

    That's when the young boy noticed an open garage (车库) and a figure that he believed was a dog outside an apartment building near his house. Given the freezing weather, the young boy got a feeling that something was not right. But instead of dismissing it like most kids at his age, he insisted that his mother, Dawn, find out what was going on. Dawn tried to make Danny believe that no one would leave a dog out in such cold weather, but he refused to take no for an answer.

    Dawn finally gave in and decided to drive to the area with the family dog and see if there was any truth in Danny' s hunch (直觉). Sure enough, as she got closer to the apartment building she noticed a garage that was wide open and someone waving madly for help. Upon getting there, she realized that it was not a dog the young boy had seen, but Kathleen St. Onge. The 80-year-old woman had fallen down on some ice in front of her garage and had been lying there for two hours, unable to get up.

    Dawn rushed home to get her husband to help and called 911. The two then returned with some blankets to cover Ms. St. Onge, while they were waiting for the ambulance to arrive. Though still in hospital, the elderly woman is recovering well and forever grateful to Danny for following his hunch!