Students and Technology in the Classroom

    I love my blackberry—it's my little connection to the larger world that can go anywhere with me.I also love my laptop computer,as it holds all of my writing and thoughts.Despite this love of technology,I know that there are times when I need to move away from these devices（设备）and truly communicate with others.

    On occasion,I teach a course called History Matters for a group of higher education managers.My goals for the class include a full discussion of historical themes and ideas.Because I want students to thoroughly study the material and exchange their ideas with each other in the classroom,I have a rule—no laptop,iPads,phones,etc.When students were told my rule in advance of the class,some of them were not happy.

    Most students assume that my reasons for this rule include unpleasant experiences in the past with students misusing technology.There's a bit of truth to that.Some students assume that I am anti-technology.There's no truth in that at all.I love technology and try to keep up with it so I can relate to my students.

The real reason why I ask students to leave technology at the door is that I think there are very few places in which we can have deep conversions（转变）and truly engage complex ideas.Interruptions by technology often break concentration and allow for too much dependence on outside information for ideas.I want students to dig deep within themselves for inspiration and ideas.I want them to push each other to think differently and make connections between the course,the material and the class discussion.

    I've been teaching my history class in this way for many years and the evaluations reflect student satisfaction with the environment that I create.Students realize that with deep conversation and challenge,they learn at a level that helps them keep the course material beyond the classroom.

    I'm not saying that I won't ever change my mind about technology use in my history class,but until I hear a really good reason for the change,I'm sticking to my plan.A few hours of technology-free dialogue is just too sweet to give up.

    The TV science-fiction series Star Trek no longer looked far-fetched (牵强的) as four men and four women in black space-suits locked themselves into a giant hi-tech greenhouse, known as a ‘biosphere', in the Arizona desert yesterday for a two-year study of the environment.

    As dawn broke over the Santa Catalina mountains, the eight waved goodbye to television cameras. Edward Ross, their multibillionaire sponsor from a Texas oil family, closed the door of the $150 million structure, with its mini-ocean, marsh, desert, savanna, rain-forest and 3,800 plant and animal species designed to allow the team to recreate Earth and its ecosystems.

    The so-called Biosphere 2 is the latest of a dozen environmental projects started by the self-titled ‘ecopreneur'. The project's main aim is to set up a self-sustaining community for possible use in a spaceship or on another planet. The crew members must plant, harvest and process their food on a half-acre farm in the seven-storey glass and metal structure, while conducting a series of experiments.

    ‘We will be custodians (监护人) of our new little world,' said Abigail Mayer, aged 31, a US marine biologist on the team, her voice choking with emotion. ‘It is a brave new step.' Many scientists, however, are more than skeptical. They point out that the largest closed ecosystem which survived more than a few days was smaller than a football. It was developed at the University of Miami and contained only shrimp, algae and other micro-organisms.

    Critics have also accused Mr. Ross of being more interested in producing a profitable theme park than in carrying out serious scientific research. Hundreds of tourists visited the site daily in the summer before it was occupied by the team. They paid $9.95 to enter and all stopped at the souvenir shop.

George Gershwin, born in 1998, was one of America's greatest composers. He published his first song when he was eighteen years old. During the next twenty years he wrote more than five hundred songs.

Many of Gershwin's songs were first written for musical plays performed in theatres in New York City. These plays were a popular form of entertainment in the 1920s and 1930s. Many of his songs have remained popular as ever. Over the years they have been sung and played in every possible way — from jazz to country.

    In the 1920s there was a debate in the United States about jazz music. Could jazz, some people asked, be considered serious music? In 1924 jazz musician and orchestra leader Paul Whiteman decided to organize a special concert to show that jazz was serious music. Gershwin agreed to compose something for the concert before he realized he had just a few weeks to do it. And in that short time, he composed a piece for piano and orchestra which he called Rhapsody in Blue. Gershwin himself played the piano at the concert. The audience were thrilled when they heard his music. It made him world-famous and showed that jazz music could be both serious and popular.

    In 1928, Gershwin went to Paris. He applied to study composition (作曲)with the well-known musician Nadia Boulanger, but she rejected him. She was afraid that classical study would ruin his jazz-influenced style. While there, Gershwin wrote An American in Paris. When it was first performed, critics (评论家)were divided over the music. Some called it happy and full of life, to others it was silly and boring. But it quickly became popular in Europe and the United States. It still remains one of his most famous works.

    George Gershwin died in 1937, just days after doctors learned he had brain cancer. He was only thirty-nine years old. Newspapers all over the world reported his death on their front pages. People mourned the loss of the man and all the music he might have still written.

    Can you imagine four hours of your day getting to and from work? For the last eight years, Jo Meade rode her bike each Sunday on a 16-mile round trip to her job washing dishes. It took more than an hour each way. Other days of the week she would spend two hours on three buses from her apartment to get to the other work, for a four-hour round trip.

    That was the “before” part of her life. The “after” part of her life was started by the community Police Officer Trevor Arnold, who delivered a used car to her with the help of a car dealer and other donors.

    Arnold, who spotted Meade, red and sweaty, riding her bike in the worst heat this summer, decided he would het her a car. He intended to quietly buy her a used car out of his own pocket so he turned to his friend Kody Slaght, a car salesman to ask about a car priced $1,000. That wasn't enough for a reliable ride, Slaght said, but the dealership said they would find a good car for her at a good price. Soon others were donating. Slaght and Arnold wouldn't say how much the car cost, but the value is about $4,000.

    Arnold said he was motivated by Meade's work ethic（职业道德）to help. “I see a lot of hardworking people nut that's when they are at work. Can you imagine spending four hours of your day getting to and from work?” he said.

    Meade's boss said she was awesome and really reliable when she worked and she got along with others. “She's willing to rise the three buses to get in here on her day off if we need her too.”

    Meade said she was planning to buy a car, “but I haven't been able to afford it,” she said. “Trevor, he is a very good guy. I did not expect this.”

    Many years ago, people relied on the sun, the moon and stars to find their way around. Later, the compass was introduced. And now, we have satnav（卫星导航）systems to guide us. A satnav system uses groups of satellites to show the user's location. They send information to a receiver, such as a smart phone, to show us where we are.

    The earliest built satnav system is the Global Positioning System, which belongs to the US. Then there is Russia's Global Navigation（导航）Satellite System, the European Union's Galileo and China's own satellite navigation system, BeiDou.

    On October 14, 2017, an ARJ21-700 plane, which was the first domestically-produced jet equipped with the BeiDou navigation system, successfully completed a test flight. The results showed the performance of the system developed by China matches that of similar systems produced abroad, according to the Commercial Aircraft Corporation of China.

    Since its introduction in 2000, the Beidou navigation system has seen increasing numbers of applications linked to everyday life, from shared bikes to farming.

    When it comes to shared bikes, smart locks that support BeiDou chips offer more accurate positioning than others, making it easier to find a bike.

    Farmers can use BeiDou-enabled tractors to plow（犁）the soil and use unmanned aircraft with BeiDou to sow seeds, which can improve efficiency and make better use of resources. BeiDou's farming applications have spread from Heilongjiang province to Beijing, Liaoning, Shanxi, Hubei and other regions across China.

    With its many uses, the Beidou navigation system is even playing a big role in the Belt and Road Initiative（— 带—路）. “To date, the BeiDou system has covered most parts of the Asia-Pacific region, as well as counties along the Silk Road Economic Belt and the 21^st Century Maritime Silk Road” said Yang Changfeng, Chief designer of the BeiDou system.

    Today, there are more than 20 BeiDou satellites above our heads, and China plans to launch even more this year to expand the BeiDou network to better serve the Belt and Road Initiative.

    “As BeiDou expands its overseas reach, it will be increasingly popular in the logistics （物流）industry,” said Miao Qianjun, secretary-general of the navigation services association. “Ships, for example, can use it to position themselves while sailing across oceans to European countries, no longer limited to Southeast Asian regions in the near future.”

    Families should reduce exposure to synthetic chemicals found in food colorings, preservatives and packaging materials as a growing body of research shows they may harm children's health, according to a policy statement and technical report from the American Academy of Pediastrics released online.

    The statement also suggests improvements to the food additives regulatory system, including updating the scientific foundation of the U.S. Food and Drug Administrations safety assessment retesting all previously approved chemicals.

    Leonard Trasande, the author of the policy statement, to tell us more about these concerns.

Q: What are the growing number of studies showing us?

A: Over the past two decades, an accumulating body of science suggests some food additives can interfere with a child's hormones, growth and development.

    Potentially harmful effects of food additives are of special concern for children because they are more sensitive to chemical exposures because they eat and drink more relative to body weight, than adults do and are still growing and developing. An early injury to their organ systems can have lifelong and permanent consequences.

Q: What additives does the statement highlight?

A: The additives of most concern, based on rising research evidence cited in the report, include:

    Bisphenols, such as BPA, used to harden plastic containers and line metal cans, can act like estrogen（雌激素）in the body which may potentially change the timing of puberty, decrease fertility, increase body fat and affect the nervous and immune systems. BPA is now banned in baby bottles.

    Phthalates, which make plastic and vinyl tubes used in industrial food production flexible, may affect male genital development increase childhood obesity and contribute to cardiovascular disease. In 2017, the Consumer Product Safety Commission banned the use or some phthalates in child-care products such as teething rings.