On Monday, the Centers for Disease Control and Prevention predicted that 42% of Americans could be overweight by 2030. Our expanding waistlines lead to not only a medical problem, but according to a recent article In The New York Times, it could also endanger personal safety in some situations—in an airplane crash, for example.

    The New York Times' Christen Negroni reports that engineers and scientists are questioning whether airplane seats are adequately constructed to protect overweight travelers. Government standards for airplane seat strength（强度）— first set moe than 60 years ago — require that the seats be made for a passenger weighing 170 pounds (77kg). Today, the average American man weighs nearly 194 pounds (88kg) and the average woman 165 pounds (75kg). Negroni reports:

    “If a heavier person completely fills seat, the seat is not likely to behave as intended during a crash,” said Robert Salazar, the leading scientist at the Center for Applied Biomechanics at the University of Virginia. “The energy absorption that is built into the aircraft seat is likely to be overpowered and the passengers will not be protected properly.”

    “Nor would the injury be limited to that passenger only,” Dr. Salzar said. “If a seat or a seat belt fails,” he said, “those people who are seated nearby could be endangered from ‘the uncontrolled movements of the passenger'.”

    Most complaints about airplane seats focus on their lack of comfort and high ticket price, and whether overweight passengers should be made to buy two seats. But The New York Times' article brings up another reason to feel anxious about flying. Investigators of the issue got in touch with the airplane seat and seat belt makers, but they refused to comment on the problem. Experts agreed that crash testing should be done with overweight dummies （人体模型）. Both airplane seats and seat belts should be tested, they said.

    Fortunately, however, according to Nora Marshall, a senior adviser at the National Transportation Safety Board, the board's investigators have never seen an accident involving a commercial plane in which the weight of a passenger was a problem.

    I log onto a computer at the doctor's office to say I have arrived and then wait until a voice calls me into the examination room.

    There, a robotic nurse directs me onto a device and then takes my blood pressure. Some time later, in steps the doctor, who is also a robot. He notes down my symptoms and gives me a prescription (处方). I pay for my visit using a credit card machine and return home without having met another human being.

    When I call my dentist's office and actually get a human being on the line, I am thrilled. And when I see the introduction of yet more self-service checkout stations at the grocery store, I feel like shouting, “When it comes to cashiers, make mine human, please!”

    After all, human cashiers sometimes give you a store coupon (优惠券) for items you are buying. Even more than that, real-life cashiers often take an interest in particularly cute children, which can brighten a young mother's day. A cashier may also show compassion (同情) for an elderly person struggling to get that last penny out of her purse.

    What technological device would do any of this? I don't want to go back to the Stone Age, but I'm also worried about a world run by machines. Sometimes when you're chatting with someone, you discover things you need to know. Maybe a receptionist needs prayers said for a sick child. Maybe a salesperson can offer a bit of encouragement to a customer who is feeling tired.

Machines can be efficient and cost-effective and they often get the job done just fine. But they lack an element so important to everyday life.

    Call it the spirit, the soul or the heart. It is something no machine will ever have. It is being human that prompts us to smile at others, which may be what they need at that moment.

    A year after graduation, I was offered a position teaching a writing class. Teaching was a profession I had never seriously considered, though several of my stories had been published. I accepted the job without hesitation, as it would allow me to wear a tie and go by the name of Mr. Davis. My father went by the same name, and I liked to imagine people getting the two of us confused. "Wait a minute," someone might say, "are you talking about Mr. Davis the retired man, or Mr. Davis the respectable scholar?"

    The position was offered at the last minute, and I was given two weeks to prepare, a period I spent searching for briefcase and standing before my full-length mirror, repeating the words, "Hello, class. I'm Mr. Davis." Sometimes I would give myself an aggressive voice. Sometimes I would sound experienced. But when the day eventually came, my nerves kicked in and the true Mr. Davis was there. I sounded not like a thoughtful professor, but rather a 12-year-old boy.

    I arrived in the classroom with paper cards designed in the shape of maple leaves. I had cut them myself out of orange construction paper. I saw nine students along a long table. I handed out the cards, and the students wrote down their names and fastened them to their breast pockets as I required.

    "All right then,'' I said." Okay, here we go." Then I opened my briefcase and realized that I had never thought beyond this moment. I had been thinking that the students would be the first to talk, offering their thoughts and opinions on the events of the day. I had imagined that I would sit at the edge of the desk, overlooking a forest of hands. Every student would shout. "Calm down, you'll all get your turn. One at a time, one at a time!"

    A terrible silence ruled the room, and seeing no other opinions, I asked the students to pull out their notebooks and write a brief essay related to the theme of deep disappointment.

    She was returning from teaching out in a small community. It was a black, moonless night, and a heavy snow was falling.

    She thought back to the time when she had first started teaching out in small communities. During those days she had always picked up hitchhikers (搭便车者), until the day her sister told her that one of her friends had been shot in the head by a hitchhiker, all because she had stopped out of kindness to help him during a storm.

    Her family didn't stop worrying about her safety over the hitchhikers until the family heard the promise: “No more hitchhikers!” The snow that night was making her think back to this.

    Then she saw a man waving. She slowed down for him, but as he ran toward the car in the dark, she shook with fear. Yet she thought that if he was truly in need, she couldn't leave him here in this storm.

    The stranger explained that his car was dead, and she told him to get in. They drove for an hour into the next city and she took him to a convenience store. She waited until he had made a call. When he reported back to her that a family member would soon come to pick him up, she wished him well and then left.

    Tears fell on her cheeks as she drove away. It felt as though she had been holding her breath for an hour.

    “I hope they'll understand why I had to break my promise,” she thought.

    China's government has been trying all measures to reduce pollution in the past few years. Now people can enjoy a fresh environment everywhere. The following two graphs are adopted from the column of “City Information” on the webpage of Beijing Review.

Graph 1: Olympic Cities Air Quality Report

Graph 2: Chinese National Standard

Notes:

    API stands for Air Pollution Index(指数).

    Particulate matter (PM10) is a major component of air pollution that threatens both our health and our environment. It consists of very small liquid and solid particles floating in the air.

    Sulfur dioxide(SO₂) acts as an acid. Inhalation(吸入) results in labored breathing, coughing, or a sore throat and may cause permanent lung damage.

    One of the biggest social issues in Japan is the increasingly low marriage rate among young people and the small birth rate, which led to an aging and eventually shrinking（萎缩） population. Most young Japanese women simply don't seem interested in having many children.

    Now what began in Japan is happening globally. As David Brooks wrote, birth rate is becoming smaller in much of the world, from Iran — 1.7 births rate per woman — to Russian, where low birth rates connected with high death rates mean the population is already shrinking. And this includes US, which has long had higher birth rates than most developed nations. Aging countries will face the burden of caring for large elderly populations without a larger resource of young workers.

    It's true that global aging is going to present some major challenges. Who will take care of the elderly? Will an older world be less active and slower to change and adapt? It's all true. Sometimes I worry about a coming generational war over resources, just as I worry about how I will take care of my own parents in their old age, just as I worry about who might take care of me.

    But here's the thing: an older world may have less pressure on the environment. As we all know, the environment is the real victim of overpopulation.

    So maybe a world that grows slower and grows older will put less pressure on the environment, and buy us a few more years to ensure our energy use, along with our birthrates, reaches a sustainable（可持续的）level. After all, we're supposed to get smarter as we got older. Hopefully that holds true for the planet as well.