I have two sons. They are as different as night and day. My youngest is sweet, loveable, easy-going, and finds joy in everything. My oldest we've nicknamed the “Evil Genius” is ambitious, self-confident, and suffers no fools. Whenever we mentioned Santa my husband and I were rewarded with major eye rolling and deep sighs from my oldest. At first we both tried to ignore it.

    We both knew that our eldest had figured out the big secret. But I'd be damned(指责) if he was going to ruin it for his six-year-old brother who had plenty of Santa-loving years ahead of him. I looked at my husband in the eye and said, “I'll handle this.” to which he responded “Okay just be careful because I'm not sure he knows - he might just be acting like it.” But I knew. And I had it in my mind that he was about to break his younger brothers spirit and break the news to him. I was afraid he was going to take the Christmas spirit away from my sweet innocent youngest and stamp all over it. I had to protect him. I needed to control this now before it got out of control. I rushed into the play room where my oldest was playing alone. I looked him dead in the eyes and said: “Well you know Santa isn't real, right?” And as I stared at my eight-year-old son for what seemed like a long time of silence, his eyes started to fill with tears. And a tear dropped down his cheek when he screamed out, “He's not?” “Um well it's not that he's not real (shut up you idiot- stop saying he's not real), but he doesn't really make and deliver all the toys. Dad and I get some of them for you. So he's real. He's just got a little help from us.”

    The Evil Genius wasn't buying it. He just sat there looking at me with an expression of doubt. You know when you make a terrible mistake but you can't stop yourself from making it worse? That was me because I just had to know. I had to know why he had seemed to be over Santa. So I asked him why he rolled his eyes and sighed every time his father and I mentioned Santa, to which he replied that kids at school had been saying Santa wasn't real but that he still thought he was.

    A woman lost the sight in one eye after going swimming in a pool at a hotel wearing contact lenses（隐形眼镜）. Jennie Hurst, from Southampton, suffered from a rare and painful infection caused by amoeba（变形虫）in water. The infection causes people to be sensitive to light and the 28-year-old said she had to stay in a dark room for three months. She is now warning of the dangers of swimming or showering wearing contacts.

    Ms Hurst experienced four operations and a treatment in which she had eye drops every half hour. "During that time I stayed in my bedroom with black curtains at the window. The only thing I could do was to listen to the radio. One evening, I was so eager to look out of window to get a look of the outside world that I opened my curtains in the middle of the night. As soon as I did this the moon shone in my eyes and it really hurt. I didn't do that again. I have been left with no sight in my left eye and the damage to my right eye could be lasting," she said.

    Ms Hurst had been wearing contact lenses for five years. "I don't even like swimming,"she said. "My friends were quite surprised that I had gone swimming and probably thought that I had been a bit lazy. I wasn't aware of the problem at all — it didn't even enter my brain to take them out. I felt responsible that I had let it happen when actually I could have just taken my contacts out."

    There is a story about a man who lost his legs and left arm in an accident. After the accident, only a finger and thumb on his right hand remained.

    He was a brilliant, creative, and educated man. He had gained a lot of experience while traveling around the world, so he became very depressed after his accident. He was afraid that he would spend the rest of his life suffering and would no longer be able to spend his life in a meaningful way. Then, he realized that he still had partial function of his right hand and could still write even though it was very difficult. An idea occurred to him. “Why not write to other people who need encouragement?”

    He wrote to the prison ministry about sending letters to the prisoners. The prison minister replied, “Writing to the prisoners is acceptable, but your letters will not be answered.”

    Filled with excitement, the man knew he could write his letters. He began sending one-way messages of God's love, hope, strength, and encouragement. He wrote twice a week, testing his strength and ability to the limit. He poured his heart and soul into his words and shared his experience, sense of humor, optimism, and faith.

    It was difficult to write those letters, especially without hope of a reply. One day he received a letter from the prison ministry. It was a short note from the officer who monitored and checked the prison mail.

    The letter said, “Please write on the best paper you can afford. Your letters are passed from cell (囚房) to cell until they literally (逐字地) fall to pieces!”

    No matter what circumstances life may present, we all have unique experiences, abilities, and God-given talents. We can discover ways to reach others who desperately need messages of encouragement and strength.

    A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.

    “It's extremely important for us to think about this as a whole system and not just a bunch of individual components (零件),” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. “The added difficulty with such a project is that actually none of those components are off the shelf and so we have to make them all on our own,” he said.

    They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of individual components, each of which individually has to perform well, and then has to be matched well to everything it's connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.

    Wood says the design offers a new way to study flight mechanics and control at insect- scale. Yet, the power, sensing and computation technologies on board could have much broader applications (应用). “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”

    Breathing dirty air comes at a high price. Air pollution lowers the average life spans (寿命) by a year worldwide and in more polluted parts of Asia and Africa, dirty air shortens lives up to twice that much. Scientists shared their new findings in Environmental Science & Technology Letters. The study used data gathered in 2016 as part of a project known as the Global Burden of Disease and was the first major country-by-country look at the connection between the length of life and what's known as fine PM.

    Air pollution has been linked to many health problems. Most earlier studies had looked at how tiny air pollutants affected rates of illness or death. Joshua Apte is an environmental scientist at the University of Texas at Austin. By looking at life expectancy (预期寿命), his team had hoped to make the threat easier to understand. PM2.5 is what scientists call tiny particles (颗粒) of pollution in the air. Higher levels of PM2.5 can cause health problems and cut months, if not years, from the average length of life. This analysis shows how pollution affects life expectancy in different parts of the world.

    The World Health Organization (WHO) recommends limiting PM2.5 to 10 micrograms per cubic meter of air. Apte's group calculated how holding pollution to this low level would help people. In countries with very dirty air, meeting this standard would lengthen people's lives. However, in countries whose air already meets this standard, the study shows no gain in life expectancy. In other words, meeting the WHO standard won't reduce health costs resulting from dirty air because even below 10 micrograms per cubic meter, pollution still causes serious risks. Meanwhile, the scientists compared how other threats including smoking and cancer shorten the length of life across the globe.

    Brian Hamilton's life changed in a prison when he was accompanying his friend, Reverend Robert J. Harris, who often went to local prisons to do his work. During the visit, Hamilton started talking to one of the prisoners and asked what he was going to do when he got out.

    "He said he was going to get a job," Hamilton recalls(回忆). "I thought to myself, wow, that's going to be difficult with a criminal background."

    The conversation made Hamilton consider how prisoners could benefit from entrepreneurship, something he thought about for years. Finally in 2008, 16 years after that initial conversation, Hamilton created Inmates to Entrepreneurs, a nonprofit organization that helps people with criminal backgrounds start their own small businesses. "Harris and I taught our first course at a prison called 'How to Start Your Own Business When You Get Out'," he recalls.

    At the time, Hamilton was building his own company, Sageworks. As Sageworks grew, so did Hamilton's time spent teaching at prisons throughout North Carolina.

    Eventually, Hamilton decided it was time to change his focus to his true passion. In May 2018, he sold his stake(股份) in Sageworks, focusing his commitment on Inmates to Entrepreneurs.

    "Now, anyone is able to access the curriculum, either to become an instructor to go into prisons to teach it or to access it for themselves as a prisoner or part of the general population," Hamilton explains. In addition, he visits middle schools and presents the curriculum to at-risk students as a preventative measure against crime.

    The free curriculum is funded by the recently established Brian Hamilton Foundation, which offers assistance to military members as they adjust to civilian life and provides loans to small businesses. "We're giving prisoners something they can do independent of a system that isn't working for them. If you can let people know that other people care about them, it makes a difference."