The Boy Made It!         

    If humans pump enough carbon dioxide (CO₂) into the atmosphere, the stratocumulus clouds(层积云) could disappear, and the earth's temperature could climb sharply to heights not predicted in current climate models. It would burn the planet. That's the conclusion of a paper published in the journal Nature Geoscience and described in detail by Natalie Wolchover for Quanta Magazine.

    As Wolchover explained, clouds have long been one of the great uncertainties of climate models. Computer models that easily capture the complexity and detail of most climate systems just aren't powerful enough to predict worldwide changes in cloud behavior. But clouds are important. They reflect sunlight away from the earth's surface. And stratocumulus clouds are those white blankets you might have seen as you looked out the window of arm airplane, rolling out below you and hiding the ground Researchers suspect that certain sudden, past jumps in temperature may have been caused by changes to clouds like these.

    For the new research, scientists modeled just a small patch of sky using a supercomputer. They found that if carbon dioxide levels reach about 1, 200 parts per million(ppm) in the atmosphere, stratocumulus clouds break up. That's a very high carbon dioxide concentration.  Right now, levels have climbed past 410 ppm--a dangerous change from 280 ppm before the Industrial Revolution.

    But humans put more and more CO₂ into the atmosphere every year. If current trends continue, the earth could reach 1, 200 ppm within 100 to 150 years. This could happen if our society doesn't follow through on any of its commitments to reduce emissions(排放), Wolchover reported. And even if it does, the result would be another 8 degrees Celsius of heat added to the global average, on top of the dangerous changes already underway due to greenhouse gases.

    That's an enormous change, and it goes beyond predictions of worldwide ice melt and catastrophic sea level rise. And, once the stratocumulus clouds are gone, Wolchover reported, they likely wouldn't reappear until atmospheric carbon dioxide levels dropped below where they are currently.

    There's still some uncertainty in the data. The 1, 200 ppm figure could change as scientists look into the issue further.

    Gregory Kloehn digs through dustbins every day, but not for the reason that most people would think. He isn't homeless. In fact he is trying to help the homeless.

    Gregory began his life as a sculptor. But he often felt that his sculpture (雕塑) which just stood in rich people's houses for years, lacked a meaningful purpose. So in 2015 he decided to put his artistic energies into creating homes to sell—not ordinary homes but small structures built entirely from recycled materials.

    The thought of creating homes for the homeless didn't come to him until the year 2017, when a homeless couple asked him for a tarp (防水布). Instead of a tarp, Gregory offered them something better: a small home with a water tank, a kitchen and a tap for waste. They were so grateful that Gregory decided to focus his efforts on helping house the homeless population in his city. And soon his "Homeless Homes Project" was started.

    Before starting a new home, Gregory goes hunting for materials by digging through dustbins. Everything he finds is usable—refrigerator doors become house doors; washing machine doors often serve as windows, and the tops of cars become strong roofs. He put wheels at the bottom for users to move their homes around easily. Each home takes two to three days to make.

    So far Gregory has donated dozens of homes to the city's most needy. While his small low- cost mobile homes are not the final solution to the problem of homelessness, they are really practical and do provide a warm and safe place for the homeless to stay in. They are simply a way for one man to do something nice for those in need of some help.

    Gregory has written a book titled Homeless Architecture, where he explains techniques to build those homes and he is now working on weekend workshops. "A lot of people who hear about what I'm doing want to get involved," he said. "Maybe we can meet someplace and put a couple of homes together."

    NEW HAVEN, Connecticut—A surprise awaited students in Yale who showed up for Professor Laurie Santos's class. They got slips of paper that said, "No class today." There was only one rule for the students' unexpected free time—They were not allowed to study, but to relax. Since exams and papers were coming up, everyone was tired and stressed. At this moment they were touched. With around applause, nine students hugged Santos, and two burst into tears.

    Yet, cancelling class was not just a break. It was also a challenge, as she was asking them to stop worrying about their grades, even if it was just an hour. One student went to the Yale University Art Gallery for the first time in her four years at Yale. A group of students went to a recording studio and played a new song. More people were outside, and more were smiling. That's why about 1, 200 students were taking Santos's class, called "Psychology and the Good Life," the largest class in Yale's 317-year history. Even non-Yale students had the chance to take Santos's class. It was offered as an online course and she immediately became an Internet hit.

    Skyler Robinson, one of her students, was at a loss for a while about what to do during his break, and then decided to take a nap. "It was a great nap," he commented. Santos designed the class after she realized that her students kept busy through long days that seemed far more depressing and joyless than her own college years. "They feel they're in this crazy rat race. They're working so hard that they can't take a single hour off. That's awful."

    The ideas behind the class are simple. Santos said, "It is the hope that science can help students find peace among all the stresses and difficulties they face at college." The lessons include showing more gratitude, performing acts of kindness and increasing social connections. The students really wanted to learn to lead a happy life in a science -driven way. Santos also noted the psychological happening of "mis-wanting", which led people to work towards the wrong goals in life.

    One week, Santo asked students to exercise. Another week, she wanted them to get more sleep. They worked hard to keep some new habits. Social science research led to many new understandings of how people find happiness. She thinks her class can change Yale, or rather, not just Yale.

    At the age of 14, James Harrison had a major chest operation and he required 13 units (3.4 gallons) of blood afterwards. The blood donations saved his life, and he decided that once he turned 18, he would begin donating blood as regularly as he could.

    More than 60 years and almost 1,200 donations later, Harrison, whose blood contains an antibody (抗体) that has saved the lives of 2.4 million babies from miscarriages (流产), retired as a blood donor on May 11. Harrison's blood is valuable because he naturally produces Rh-negative blood, which contains Rh-positive antibodies. His blood has been used to create anti-D in Australia since 1967.

    "Every bottle of Anti-D ever made in Australia has James in it," Robyn Barlow, the Rh program director told the Sydney Morning Herald. "It's an amazing thing. He has saved millions of babies. I cry just thinking about it." Since then, Harrison has donated between 500 and 800 milliliters of blood almost every week. He's made 1,162 donations from his right arm and 10 from his left.

    "I'd keep going if they let me," Harrison told the Herald. His doctors said it was time to stop the donations — and they certainly don't take them lightly. They had already extended the age limit for blood donations for him, and they're cutting him off now to protect his health. He made his final donation surrounded by some of the mothers and babies who his blood helped save.

    Harrison's retirement is a blow to the Rh treatment program in Australia. Only 160 donors support the program, and finding new donors has proven to be difficult. But Harrison's retirement from giving blood doesn't mean he's completely out of the game. Scientists are collecting and cataloging his DNA to create a library of antibodies and white blood cells that could be the future of the anti-D program in Australia.

I had a terrible experience last year. One night my younger brother, Chase, was driving us home from our weekly cleaning of the church. We were both getting 1 , so we picked up a couple of energy drinks at a gas station. Then we jumped onto the freeway and 2 home.

The ride was fine. My brother was focused, so I 3 my eyes. I woke up when we were close to our exit. But the car 4 turned to the right. I did not care at first because Chase often played jokes. Then I 5 it was not a joke at all.

I shouted my brother's name at the top of my 6 . He woke up from his sleep in time to slam on the brakes, though the brakes did little to 7 us down. We crashed into a streetlight, 8 us hit the dirt hill of the off-ramp (出口匝道).

Then I 9 something white and bright shoot toward my chest. It hit me and left me breathless but 10 me from the dashboard (仪表盘). The streetlight swung around, hitting two other 11 and then crashed back onto the hood of our car. One inch 12 to us, Chase and I wouldn't be here today. A kind man 13 us out of our car, and the policeman came to 14 us. They said there were no broken ribs (肋骨) and no internal bleeding.

Our dad 15 on the scene in his car and drove us home. From that day on, we never drove while we were sleepy or tired again.