The Blue Light From Digital Device

More devices like the iPhone, iPad and Kindle produce a blue light that causes our sleep to be restless and disturbed, according to a new study.

The study was led by Dr Paul Gringras, a sleep disorder specialist at a children's hospital in London. Together with her colleagues, Gringras found that manufacturers have started making bigger, brighter, bluer screens in an effort to increase the efficiency of our screens during daytime.But, as an unwanted byproduct, this light is affecting our sleep and productivity.

The study said that this type of light is likely to cause the most disturbance to sleep, as it most effectively overpowers melatonin (褪黑素). a hormone①that reminds us to sleep every night. Besides, using our devices before bedtime could even affect our performance during the day, because exposure to this blue light changes our body's natural rhythms.

“The development of light-producing devices means that for many people, a 'book at bedtime'is now often an‘e-book’,” Gringras pointed out.“Reading a traditional paper book by the light of your bedside lamp doesn't affect your sleep, because bulbs produce a yellow-red light. In comparison, the same book read in electronic arrangement will provide a very different light signal with biological effects.”

The researchers called on all device manufacturers to adjust screen lighting for the sake of the users’sleep quality and overall health.“All hardware devices should have an automatic “bedtime mode”that shifts blue and green light production to yellow and red as well as reduces backlight/light intensity,” Gringras said.

“And, we hope that as technology improves, more and more people will realize that‘brighter’will not always be equal to‘better’,”the researchers concluded.

① hormone: a chemical in your body that stimulates certain organs of your body

The frightening day of our diving test was here. Our parents thought we were lucky to have an Olympic-size swimming pool at the school. My mom stressed that the swimming pool was one of the best in our city. But I didn’t feel happy about it at all. Instead, I felt afraid of the swimming pool. It was mainly because I was terribly shy.

I was so shy that I always sat at the back of the room in class so I’d not be called upon to read. As for the present physical education class each Monday morning, I would work my way to the back of the line forming at the diving board so I would not have to practice the dives.

Now, it was another Monday morning - the morning of our diving test. My blood ran cold when the teacher Ms. Robbins announced that we would be graded for our final on the most difficult dive- the jackknife. And she added, “This diving test is important. The one who fails has to spare time in the following Monday mornings to practice diving in this swimming pool and attend this test again.”

My body kept shaking with fear as the line to the scary diving board shortened. As I watched, each student seemed to perform the challenging dive effortlessly. And shortly I would have to attempt something that I had never even practiced before.

Then I remembered someone telling me that when you picture yourself doing a skill over and over, it’s just as effective as physically practicing that skill. So I watched carefully as each classmate jumped at the end of the board once, added a jump for height, folded their body in half to reach for their toes, and finally straightened out like an arrow for going into the water. After carefully watching for a while, I was actually in a state of surprise, because all of a sudden I realized that it was possible for me to perform these four steps of diving.

Eventually all classmates except me finished jumping. The teacher announced that it was my turn.

With my heart knocking wildly, I walked down the diving board towards its end.

Knowing I failed, I climbed out of the pool, embarrassed.

My parents came to the US from India in the 1960s, along with other immigrants from India. Back then, there were few Indians anywhere around the US. My father came to Kansas,where he would get his Ph.D. Six months later, my mother came with the three of us kids — my sister, my brother, and me. We were just six,five and three years old then.

It was the very first winter when we were in Kansas. It was so cold,but we didn’t have heavy coats or warm clothes. We didn’t have a concept of how cold it really could be in the Midwest, and there was a new surprise every day. We didn’t have a car or anything like that, and my dad didn’t have a US driver’s license. But anyway, my father was studying for his Ph.D., and he would walk up and down a big hill to and from the campus on a regular basis.

Since I was three years old, I didn’t go to school, but my sister and brother were in school. My father had to walk down the big hill to take them to school every day and then walk back up the hill to go to university.After about three weeks of living like this, a woman called Valerie,whose son John was in the same class as my brother, started noticing them. On a very cold snowy morning,when they went to school as usual,Valerie passed by. She pulled up and said, “I see you on the way every day. Don’t you feel cold without coats?”My father responded,“We didn’t expect the weather would be so cold in Kansas.”Valerie said,“Maybe I can take your daughter and son to school. Would you like a ride?”

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Hearing that, my dad nodded with great joy.

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Later, Valerie and her family became so dear to my family.

Jen and her brother, Rick, live on the west coast of Australia; swimming and surfing have become a routine for them. They see all kinds of fish, such as lovely dolphins, huge whales and even fierce sharks.

Last weekend, Jen was on beach, standing on the hot sand. Enormous waves crashed along mile after mile of beautiful sand. Rick was happy because he had a new surfboard Rick’s favorite sport is surfing.

“I’m going to look at the fish underwater,” Jen waved to Rick, putting her blue rubber fins on her feet. Then she put the yellow mask and snorkel on her face.

The water was warm. Jen took a big breath and dived down and down. She could see fish and plants through her mask and the fish swam all around her. Jen observed or touched the tall or small plants growing on the rocks. Some were soft and some rough. Fish live in the plants and rocks.

Jen was swimming past a large rock when she saw a blue dolphin keep still.

Trapped in a net around the rock, the dolphin wasn’t able to swim up to get air. Moving its fins painfully, the poor blue dolphin was dying slowly.

Immediately, Jen pulled the net from the rocks and then freed the dolphin. It moved its fins quickly and swam up. It took a breath of air. The blue dolphin looked down at Jen gratefully, swimming away.

On the way home, she told her brother about her adventure with the blue dolphin with great interest.

The following day it was still hot, and more people swam in the sea, playing and laughing. The hot sun shone, and the water was silver and blue.

Some lifeguards watched the swimmers closely as they stared at the sea in the distance. Suddenly, one shouted loudly, “Shark! Quick!” Hungry, a shark was swimming quickly towards the swimming people. Everybody was frightened and began to swim towards the beach.

Jen and Rick were swimming a long way from the beach.

All of a sudden, Jen saw another fin in the water.