Salt plays an important role in our daily diet. Even a small reduction(减少) in salt in the diet can be a big help to the heart. A new study used a computer model to predict -how just three grams less a day would affect heart disease in the United States.

    The result: Thirteen percent fewer heart attacks. Eight percent fewer strokes（中风）. Four percent fewer deaths. Eleven percent fewer new cases of heart disease. And two hundred forty billion dollars in health care savings. Researchers found it could prevent one hundred thousand heart attacks and ninety-two thousand deaths every year．

    The study is in the New England Journal of Medicine. Kirsten Bibbins-Domingo at the University of California San Francisco was the lead author. She says people would not even notice a difference in taste with three grams, or one-half teaspoon, less salt per day. The team also included researchers at Stanford and Columbia University.

    Each gram of salt contains four hundred milligrams of sodiu(钠), which is how foods may list their salt content．

    The government says the average American man eats ten grams of salt a day. The American Heart Association advises no more than three grams for healthy people. It says salt in the American diet has increased fifty percent since the nineteen seventies, while blood pressures have also risen. Less salt can mean a lower blood pressure.

    New York City Mayor Michael Bloomberg is leading an effort called the National Salt Reduction Initiative. The idea is to put pressure on food companies and restaurants. Critics call it government interference(干预).

    Mayor Bloomberg has already succeeded in other areas, like requiring fast food places in the city to list calorie information. Now a study by the Seattle Children's Research Institute shows that the calorie information on the menu can influence what parents order for their children. Ninety-nine parents of three to six year olds took part. Half had calories between the two groups for foods that the parents would have chosen for themselves. McDonald's menus clearly showing how many calories were in each food. Parents given the counts chose an average of one hundred two fewer calories when asked what they would order for their children. Yet there was no difference in calories between the two groups for foods that the parents would have chosen for themselves.

    Study leader Pooja Tandon says even small calorie reductions on a regular basis can prevent weight gain over time. The study was published in the journal Pediatrics.

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    You may like chewing gum (口香糖) after meals to stop your breath smelling bad; or your mother might use a special neutralizer (调理剂) to protect her permed hair (烫发). But have you thought about the chemical principles behind such everyday actions?

    On March 2, the Senior 3 students from the IB (International Baccalaureate, 国际文凭) classes at Beijing Huijia Private School presented their discoveries, all in fluent English. This kind of seminar is held every year to show the achievements of the IB chemistry experiment lessons offered by the school. IB is a qualification based on a common curriculum (课程) for students aged 16-18 in any country and is recognized by universities everywhere.

    "Once I saw an advertisement for xylitol (木糖醇) gum," recalled Zhang Xinju. "Suddenly an idea came to my mind: are there any chemical reactions when the xylitol is working on our teeth?"

    Zhang and his partner Bu Xuan visited several hospitals to try and find out. "Doctors know that xylitol can protect teeth, but few could explain how the chemical reactions happen," said the 17-year-old boy.

    Presenting the results of their research in English to an audience of Chinese and foreign judges was never a problem for the students.

    "Textbooks for IB students are in English, and our teachers speak in English," explained Wei Duan and Han Yu, whose research topic was "The Acid-Base Reaction (酸碱反应) in the process of Hair-Perming".

    "In Senior 1 we often referred to Chinese textbooks, but we found we could understand and express it all in English by the second year."

    Lu Jiang, the school's IB chemistry teacher and China's only IB vice-examiner, is proud that her students can apply scientific theories they learn in class to daily life.

    "You might have learned these facts from you kindergarten teachers, but few think about the theories behind them," Lu said. "This kind of practice is intended to develop the scientific thinking they will need in their future studies."

    Graph can be a very useful tool for conveying information especially numbers， percentages, and other data . A graph gives the reader a picture to interpret. That can be a lot more pages and pages and pages explaining the data .

    Graphs can seem frightening, but reading a graph is a lot like reading a story. The graph has a title ,a main idea ,and supporting details.You can use your active reading skills to analyze and understand graphs just like any other text .

    Most graphs have a few basic parts: a caption or introduction paragraph, a title , a legend or key, and labeled axes. An active reader looks at each part of the graph before trying to interpret the data. Captions will usually tell you where the data came from (for example, a scientific study of 400 African elephants from 1980 to 2005). Captions usually summarize the author's main point as well. The title is very important. It tells you the main idea of the graph by stating what kind of information is being shown. A legend, also called a key ,is a guide to the symbols and colors used in the graph. Many graphs, including bar graphs and line graphs, have two axes that form a corner, Usually these axes are the left side and the bottom of the graph .Each axis will always have a label. The label tells you what each axis measures.

Bar Graphs

    A bar graph has two axes and uses bars to show amounts. In Graph 1 ,we see that the x-axis shows grades that students earned, and the y-axis shows bow many students earned each grade .You can see that 6 students earned an A because the bar for A stretches up to 6 on the vertical measurement. There is a lot of information we can get from a simple graph like this(See Graph 1).

Line Graphs

    A line graph looks similar to a bar graph ,but instead of Bars, it plots points and connects them with a line .It has the same parts as a bar graph – two labeled axes –and can be read the same way .To read a line graph, it's important to focus on the points of intersection rather than the line segments between the points, This type of graph is most commonly used to show how something changes over time.

    Here is a graph that charts how far a bird flies during the first Five days of its spring migration (See Graph 2).

    The unit of measurement for the x-axis is days. The unit of measurement for the y-axis is kilometers. Thus we can see that ,on the first day, the pipit flew 20 kilometers. The line segment goes up between Day 1 and Day 2,which means that the bird flew farther on Day 2.If the line segment angled dawn, as between Day 4 and Day 5,it would mean that the bird flew fewer  kilometers than the day before. This line graph is a quick, visual way to tell the reader about the bird's migration.

    Pie Graphs

    A typical pie graph looks like a circular pie. The circle is divided into sections, and each section represents a fraction of the data. The graph is commonly used to show percentages; the whole pie represents l00 percent, so each piece is a fraction of the whole.

    A pie graph might include a legend，or it might use icons or labels within each slice. This pie graph shows on month's expense, (See Graph 3 ).

    Food $ 25

    Movies $ 12

    Clothing $ 36

    Savings $ 20

    Books $ 7

    The annual World Economic Forum (经济论坛) took place in Davos, Switzerland, in Jan 23 -26, 2018. What did Chinese entrepreneurs (企业家) speak in the forum? Are there some quotable quotes for you?

    Jack Ma, founder and executive chairman of Alibaba Group

“I think globalization cannot be stopped — no one can stop globalization, no one can stop trade. If trade stops, the world stops. Trade is the way to dissolve the war not cause the war,”said Ma in Davos, “Google, Facebook, Amazon and Alibaba we are the luckiest companies of this century. But we have the responsibility to have a good heart, and do something good.”

    Richard Liu, founder and chief executive officer of JD

    “Business is not only a way to make money but also a way to contribute yourself, to help people,” Liu said in a speech in Davos.”How can we face the fractured (分化的) world? That's the topics of the Davos this year. I think a very important thing in business is cooperation. If we can unite, work together, (if) we work very closely, I think we can bring more hope to the people and we can build more trust between the people, countries and companies and partners,” he said.

    Jane Sun, CEO of Ctrip

    “Tourism is a sunrise industry. Since I entered Ctrip, every year there are new comers, which, first of all, shows that tourism is booming.” Sun told Sina.com in Davos. “We invested heavily in ABC. A refers to AI, B is big data, and C is cloud computing. As we continue to expand overseas, these three will be very good weapons for us. So we think those mean opportunity,” she said.

    Hu Xiaoming, president of Aliyun

    “In 2018, people will see the development in various countries more closely connected with cloud computing. More manufacturing enterprises and financial institutions will start to use 'cloud', and cloud computing will increase the efficiency of technology and finance,” Hu told Xinhua in Davos.

    My husband and I wanted desperately the instant transformation from typical consumers to eco-conscious people. We switched our light bulbs to CFL(compact fluorescent light) bulbs to conserve energy. We went about the house turning off lights and unplugging appliances that weren't in use. But the rate of global warming exceeded our snail's pace conversion to greenhood. So I pressed onward.

    I decided to put veganism(素食主义) at the top of our agenda. Vegans refuse any animal flesh or commercial goods made from any animal byproducts such as milk or fats. All the family applauded this option except for my husband. Some kind of animal needed to sacrifice its dear life for his meal or it was his dinner. I cooked up a storm, struggling to prepare nutritious meals dominated by not-so-obvious vegan dishes like bean burritos and high-fiber vegetable stir-fry. It took a few days before he realized that he hadn't been eating any meat.

    "I feel like eating beef." he announced. So that night, I took full advantage of a zucchini (一种南瓜), cut it into chunky(粗大的) pieces and cooked them. Then I covered them with spices. My beef-starved husband had some and a curious look crossed his face.

    "Where's the beef?"

    "Living peacefully somewhere on an open plain where it belongs."

    "I knew it" he murmured. "You've surely made great contributions to the boom in cattle." His taste buds were developed completely around the flavor of every kind of animal: cattle, pigs, deer, lamb, chickens and ducks. Converting him was like feeding grass to a lion.

    I'm all for preserving our planet, but what good would it do to save the earth for tomorrow's generation if today's died of starvation? The next day, we went out for burgers. I was very careful to place the paper bag into our recycling bin.

    Does your local high school have a student newspaper? Only 1 in 8 of New York's public high schools has student newspapers – and many of those are published just a few times a year. A few more are online, which can leave out poorer schools.

    Rebecca Dwarka, an 18-year-old senior who works for her student paper said, “Facebook is the new way of finding out what happened. Nobody wants to actually sit down and read a whole article about it. This makes a 'whole article' sound a little like a long sentence in lonely places.”

    I am not nostalgic about high school student newspapers and never worked for mine. I put out what was then called a personal magazine with a group of friends because we wanted to write about peace, war and rock 'n' roll without school officials warning us not to make jokes about the local officials.

    School newspapers are in decline because students now find out what happened on social networking websites. This is a little discouraging because it proves that for millions of Americans, journalism is becoming a do-it-yourself thing. Every citizen can be a reporter.

    When something happens, we look for social media messages. Facebook posts and Tweets have become the means by which citizens and reporters can prove, deny, pass on stories and express opinions without the press' challenging, researching or slowing the message.

    But truly good journalism is a craft, not just a blog post. It requires seeing something carefully and it uses an eye for details to help prove a larger view. And even journalism that conveys an opinion tries to be fair. If school newspapers begin to disappear, I hope there are other ways for students to learn that.