Often a nickname is a shortened form of a person's name, and it can also be a descriptive name for a place or a thing. Many American cities have nicknames. These can help build up an identity, spread pride among citizens and build their unity. Nicknames can also be funny.

    Los Angeles, California is the second largest city in population, after New York City. Los Angeles has several nicknames. One is simply the city's initials, L.A. It is also called the City of Angels because Los Angeles means "the angels" in Spanish.

    Los Angeles often has warm, sunny weather. So another nickname is City of Flowers and Sunshine. New York is called The Big Apple. So Los Angeles is sometimes called The Big Orange because of the fruit that grows in that city's warm climate.

    The American movie and television industries are based in Los Angeles. So it is not surprising that it is called The Entertainment Capital of the World. Many films are made in the area of Los Angeles called Hollywood. Millions of people visit the area. No trip to Los Angeles is perfect without seeing the word "Hollywood" spelled out in huge letters on a hillside.

    Many movie stars live in Los Angeles. The city is sometimes called Tinseltown. This nickname comes from the shiny, bright and often unreal nature of Hollywood and the movie industry.

    Another nickname for Los Angeles is La-La Land, using the first letters of Los and Angeles. This means a place that is fun and not serious, and maybe even out of touch with reality.

    A good place for watching unusual-looking people is Venice, an area on the west side of Los Angeles. A system of waterways designed after the Italian city of Venice has been built there. Many people love Los Angeles for its warm sunny weather, beautiful mountains and beaches, and movie stars. That includes Randy Newman, who sings about his hometown.

    On the whole, Los Angeles is growing attractive just for its rich nicknames.

    Exposing living tissue to subfreezing temperatures for long can cause permanent damage. Microscopic ice crystals (结晶体) cut cells and seize moisture (潮气), making donor organs unsuitable for transplantation. Thus, organs can be made cold for only a few hours ahead of a procedure. But a set of lasting new antifreeze compounds (化合物)—similar to those found in particularly hardy (耐寒的) animals—could lengthen organs' shelf life.

    Scientists at the University of Warwick in England were inspired by proteins in some species of Arctic fish, wood frogs and other organisms that prevent blood from freezing, allowing them to flourish in extreme cold. Previous research had shown these natural antifreeze molecules (分子) could preserve rat hearts at -1.3 degrees Celsius for up to 24 hours. But these proteins are expensive to extract (提取) and highly poisonous to some species. “For a long time everyone assumed you had to make synthetic (人造的) alternatives that looked exactly like antifreeze proteins to solve this problem, ”says Matthew Gibson, a chemist at Warwick who co-authored the new research. “But we found that you can design new molecules that function like antifreeze proteins but do not necessarily look like them.”

    Most natural antifreeze molecules have a mixture of regions that either attract or repel water. Scientists do not know exactly how this process prevents ice crystal formation, but Gibson thinks it might throw water molecules into push-pull chaos that prevents them from tuning into ice. To copy this mechanism, he and his colleagues synthesized spiral-shaped molecules that were mostly water-repellent—but had iron atoms at their centers that made them hydrophilic, or water-loving. The resulting compounds were surprisingly effective at stopping ice crystals from forming. Some were also harmless to the roundworm Caenorhabditis elegans, indicating they might be safe for other animals.

    “These compounds are really cool because they are not proteins—they are other types of molecules that nonetheless can do at least part of what natural antifreeze proteins do, ”says Clara do Amaral, a biologist at Mount St. Joseph University, who was not involved in the research. Gibson's antifreeze compounds will still need to be tested in humans, however, and may be only part of a solution. “We don't have the whole picture yet,”do Amaral adds. “It's not just one magical compound that helps freeze-tolerant organisms survive. It's a whole suite of adaptations.

    My friend, Jack, was a taxi driver. We became friends quite by accident. Five years ago, I made a trip to Chicago. The moment I stepped into a cab, I realized it was different. The floor was covered with a rug (小地毯). There were small reproductions of paintings by Van Gogh inside the cab. And the windows were spotless. I told the driver I had never ridden in a more attractive taxi.

    "I like to hear my passengers say that," he replied. "How long have you been decorating your cab?" I asked. "It's not mine," he said. "It's a company cab. I hit upon the idea years ago when I worked as a clean-up man for the taxi company. Each car that came in at the end of the day was like a garbage pit. Cigarette butts and matches covered the floor. Sticky stuff like peanut butter was on the seats or door handles. I thought that if the company and the drivers would give people a car worth keeping clean, they might be more considerate."

    "As soon as I got my taxi license, I tried out my ideas. I put a lot of extra decorations into the cab they gave me to drive. I got a nice rug and some flowers. When each passenger got out, I checked to make sure that everything was in order for the next fare. After about a month of my bringing in a spotless cab, the boss reserved the same car for me each day. That was when I put up the reproductions of great paintings."

    "I've never been disappointed by people in the past ten years—no garbage. Like I say, people appreciate beautiful things. If we planted more flowers and trees in the city and made the buildings more attractive, more people would tend to keep the city clean."

    Later, we became good friends. I was impressed by the taxi-driver, who had hit on a great truth—a sense of beauty comes with the gift of life. Most people don't have to be instructed about the rarity of beauty. They respond when they find it. And, if they are made to feel a part of it, they will try to add to it.

    Warford is an optometrist (验光师) in Florida. He has seen an increase in "computer vision syndrome (电脑视力综合症)"in children. "A lot more children come into the office either because their parents have noticed that they have headaches or red or watery eyes or discomfort, or because their nearsightedness appears to be increasing and they're worried," he says.

    Dr. Watford says part of the problem is that children may be more likely to pay no attention to early warning signs than adults. "Even if their eyes start to feel uncomfortable or they start to get a headache, they're less likely to tell their parents, because they don't want to have the game or whatever taken away," he explains.

    He says another part of the problem is that people blink (眨眼) less often when they use digital devices. He says, "A person who uses an electronic device blinks about one third as much as we normally do in everyday life. And that can result in the front part of the eye drying and not staying protected like normal."

    Eye doctors offer suggestions like the 20 /20 /20 rule. That means every twenty minutes look away twenty feet or more for at least twenty seconds from whatever device you're using.

    Other suggestions include using good lighting and spending less time looking at screens. Many experts say children should spend no more than two hours a day using digital devices—with no screen time for children under two.

    But not all eye doctors have noticed an increase in problems in children. Dr. David Hunter, for instance, says, "While it is possible to develop fatigue looking at screens for a long time, there's certainly no proof that it actually causes any damage to the eyes."

Four Stories in Life

A real doll

I've worked at an amusement park and when another Barbara joined the team, I changed my name tag(标签) from "Barb" to "Barbie". It was funny to see how kids reacted to my name differently. "Is she really a Barbie?" they asked. I changed it at another job, too, and began answering the phone, "This is Barbie. How can I help you?" Ninety percent of callers now respond, "Barbie, can you tell me..?" Pronouncing that long "e" sound forces your mouth into a smile. But I've found the smile is usually returned voluntarily.

—Barbie Bosco Latrobe, Pennsylvania

Rice twice as nice

We replaced rice with cauliflower(花椰菜) rice. There's not much of a difference in taste, and it cooks in minutes, and is a vegetable instead of empty carbs(精制碳水化合物).

—Michelle Byrd Marlton, New Jersey

Happy wife, happy life

Early in our marriage, my husband would come home feeling tired after work, and I'd be tired due to looking after the kids. We were both tired and bad-tempered, and we often ended up arguing. It got to a point where I worried we were on the verge(边缘)of divorce. The day I realized it, I asked myself, "Am I the person I would want to come home to?"

I began greeting him with a smile and kiss instead of complaining about my day. He'd smile back and we'd talk calmly. We still have our differences, but one small change in attitude saved our marriage forever.

—Annabelle Wallis, Pennsylvania

Our "Spoonland" and "Forkland"

We presort silverware in the dishwasher. It takes no extra time to load and makes emptying much easier. We always smile when our kids, now adults, introduce friends to "Spoonland" and "Forkland".

—Kathleen Luck, Ohio

 "A moth (飞蛾) to a flame" is often used to indicate an inescapable attraction, yet it is a strange example of animal behavior that continues to confuse people today. Scientists have raised a number of theories over the years to explain why. One holds that insects flying at night are following their nature to fly toward the brightest spot in their field of vision, which they mistake for the sky. Another suggests that insects are trying to warm themselves with the heat produced by the light. The most popular theory, though, is that insects are confusing lights with the moon or other celestial bodies (天体) that they normally use to navigate (导航).

To find out the real reason, the team carried out a first set of experiments in an insect flight area. The researchers used eight high-speed infrared (红外线) cameras equipped with motion-capture technologies to track 30 insects from three moth and two dragonfly species. They also flew lab-raised insects from six different insect orders that were too small for motion-capture technology, including fruit flies and honeybees, to make sure different insects all showed similar responses to light. Working with co-author Pablo Allen of the Council on International Educational Exchange in Monteverde, Costa Rica, the researchers put heavy cameras, lights and tripods in two field sites to gather behavioral data from insects in the wild.

The team was able to confirm that insects were not beelining to the light but rather circling it as they tilted (倾斜) in an attempt to turn their backs toward it. This behavior, known as a "dorsal light response", normally helps insects to remain in an unchanging path of flight that is properly lined to the horizon (地平线). Artificial light that arrives from a point source causes them to fly in unpredictable patterns as they try to turn their backs to what they are mistaking for the sky.

Now research might have finally solved the mystery mentioned first: artificial light confuses insects' ability to turn themselves to the horizon, confusing their sense of what is up and down and causing them to fly in circles.