In the traffic lights,red means "stop",green means "go",and yellow means "hurry": Why those colors, though? Why not blue,purple,and brown?The following are transponded from others WeChat.

●Red is an inherited symbol from railroads

    Red symbolizes danger in many cultures,which makes sense,considering it has the longest wavelength of any color,meaning you can see it from a greater distance than other colors.Red has meant "stop" since long before cars existed,with railway signals use of red dating bake to the days when mechanical arms lifted and lowered to indicate whether the rail ahead was clear.So that one's simple.

●Green meant "caution" at first

    Green's role in lights has actually changed dramatically over time.Its wavelength is next to (and shorter than) yellow's,meaning it's still easier to see than any color other than red and yellow.Back in the early days of railway lights,green originally meant "caution",while the "all-clear" light was,well,clear or white.Trains,of,course,take an unlimitedly long time to stop,and legend has it that several disastrous collisions happened after an engineer mistook stars in the night horizon for an all-clear.Thus,green became "go",and for a long time,railways used only green and red to signal trains.

●Yellow means "caution" because it's almost as easy to see as red

    From the earliest days of motoring up until the mid-1900s,not all stop signs were red-many were yellow, because at night it was all but impossible to see a red stop sign in a poorly lit area.The yellow stop-sign craze began in Detroit in 1915,a city that five years later installed its first electric traffic signal,which happened to include the very first amber traffic light,at the corner of Michigan and Woodward Aves.

    Do you often feel lonely? What do you do when you feel that way? Hide yourself away and spend your time reading, watching TV or walking around?

You might think that feeling lonely is just like feeling happy, sad or scared — that it's just one of your various moods. That is true. However, if you let yourself be lonely for too long without dealing with it, you could be making a serious mistake.

    Doctors have known for some time that feeling lonely is bad for the mind. It can lead to mental health problems such as depression, stress and reduce confidence. “Being lonely means not feeling connected or cared for, but it's not about being mentally alone,” Lisa Jaremka, scientist from Ohio State University, US, told Live Science in January. And there's growing evidence that not having friends is connected with physical illness as well.

    In 2006, for example, scientists studied 2,800 women who had cancer. They found that those who had few friends or family were five times more likely to die of their disease than women with many social contacts. Also, even healthy people had a better chance of falling ill if they felt left out by others, according to the BBC.

    The results have scientists thinking that loneliness might hurt the immune system(免疫系统), which protects the body from diseases.

    Hoping to prove this theory, Jaremka and her research team put volunteers(志愿者) through a stress test. During the test, volunteers were asked to make an unprepared speech in front of a group of stony-faced people. The researchers found that volunteers who said they were lonely in their daily lives felt more stress during the test. And their blood samples showed that all the stress had managed to cause harmful changes to their immune system.

     “Loneliness has been thought of in many ways as a chronic stressor(慢性增压器) — a socially painful situation that can last for quite a long time, ” explained Jaremka, who led the study.

    The number of people suffering from loneliness is increasing all over the world. However, solving the problem is easier said than done. It won't work to just “tell anyone to go out and find someone to love you”, said Jaremka. “We need to create support networks.”

    Cliffside Manor Apartments are conveniently located (位于) just 15 minutes from Downtown Pittsburgh, Cranberry Township, Greater Pittsburgh International Airport and Robinson Township shopping district. This community (社区) has 1 and 2 bedroom apartments for rent. Pet-free community.

    Castle Ridge Luxury Apartment Homes are located in the suburban south hills of Pittsburgh, convenient to I-279 interstate highway, Pittsburgh International Airport, and the public transit (运输) system. 1, 2 & 3 bedroom apartment homes for rent. Pets are accepted with pet fee.

    Alvern Garden Apartments are pleasantly situated in a quiet residential (住宅的) neighborhood in the suburban south hills of Pittsburgh. Close to Keystone Oaks School District and nearby restaurants and minutes to South Hills Village shopping mall. 1, 2 & 3 bedroom apartments for rent. Cats only with a $250.00 security deposit.

    The Pointe at Adams Ridge is located north of Pittsburgh with convenience to I-79 interstate highway, shopping, restaurants & entertainment. 1, 2 & 3 bedroom apartments for rent. Pets are welcome.

    A Spanish company Siesta &Go has opened the first public napping (小睡) space in Madrid. It promises people a quiet rest in the middle of the city's business center.

    Napping spaces are nothing new; places to rest are already set up in other big cities in the world. But the idea would appear to work well with the culture of Spain, where people traditionally take an afternoon nap, called siesta.

    The Madrid nap space recently opened with 19 beds. People can use them by the minute or by the hour, and they can also choose either a private or shared room. An hour of napping inside a private room costs about $ l5.

    Siesta &GO provides all bedding, clean nightshirts and other materials. Nippers can request to be woken up when their time is up. It also offers areas to work, with armchairs, newspapers and coffee for those not wishing to sleep.

    Philip &Go is one happy customer. Marco says he gets tired during the day because of hard work. He says a siesta is the perfect way to build up energy. “I come for about 30 minutes or something like that. That is usually enough for me to be full of energy.”

    While many Spanish people love their naps, others like Carlos Villarroja say they are just too busy to keep the tradition. “It's a Spanish tradition, but I think it's more of a legend (传说) than a tradition. Because of the lifestyle and the working hours, we have very little free time for a siesta at least during the week.”

    But many health experts believe there is evidence that taking a short nap can be very good for the body and mind. Scientific studies show that taking a siesta can also prevent illness and lower blood pressure.

    I was with a group of businessmen, and we were dealing with a question — what is a good person?

    At a certain point during the discussion, one of the students, a young man of about 30, described an event that happened at Christmas. He and his five-year-old son were decorating the Christmas tree, and a little boy came to the front door begging. If you ever visit Mexico, you will see that the people there take begging as nothing to get upset about and nothing to get embarrassed by.

    So, this little boy came to the door, a boy about the same age as my student's son. The father and the son went to the front door, and the father went back with his five-year-old son and said to him, “Give him one of your toys.” At the words, the little boy quickly picked up one toy, and his father said to him, “No, no, give him your favorite toy.”

    And the little boy, like a little tiger, said, “No way!” He cried; he refused. But the father, like a big tiger in a way, insisted gently, “No, you must give him one of your favorite toys.”

    And finally the boy, with his head down, picked up a toy he had just gotten. The father waited in the living room, and the boy walked to the front door with the toy in his hand. The father waited and waited.

    What do you think happened?

    After a couple of minutes, his son came running back into the living room, his face lighted up. “Daddy,” he said, “can I do that again?” I think I have got the answer to the question.

    My senior year of high school was a very hectic one, to say the least. If I wasn't studying or worrying about my grades, I was working on after-class activities. It seemed as if my life had turned into one crazy cloud of confusion and I hoped to find some sort of direction.

    Finally, I got a part-time job at the local coffee shop. I had thought it would be easy and, for the most part, stress-free. I pictured myself pouring coffee and becoming close friends with my customers.

    What I hadn't expected was the people with so many orders. There were moments when I was very angry simply because I couldn't seem to please anyone. There was always too much sugar, too little ice, or not enough skim milk. However, I kept at it.

    One day, one of my customers came in, depressed. Before he left, I handed him a bag along with his iced coffee. He looked at me questioningly because he hadn't ordered anything but the coffee. He opened the bag and saw his favorite doughnut (甜甜圈) I had given him. He smiled and thanked me before heading out into the rain.

    The next evening, he came. Instead of ordering something, he handed me a single pink rose and a note.

    “Thanks for being so sweet and thoughtful yesterday. It is so nice to meet someone who's warm and unselfish. Please don't change your ways because I truly believe that you will do better. Have a great day!”

    As time went on, I did come across some customers really particular. But anytime I felt depressed, I thought of that man and his kindness. Then I would smile, hold my head up high, clear my throat and ask politely, “How can I help you?”