I am peter Hodes ,a volunteer stem courier. Since March 2012, I've done 89 trips of those , 51 have been abroad, I have 42 hours to carry stem cells（干细胞）in my little box because I've got two ice packs and that's how long they last, in all, from the time the stem cells are harvested from a donor(捐献者) to the time they can be implanted in the patient, we've got 72 hours at most, So I am always conscious of time.

I had one trip last year where I was caught by a hurricane in America. I picked up the stem cells in Providence, Rhode Island, and was meant to fly to Washington then back to London. But when I arrived at the check-in desk at Providence, the lady on the desk said: “Well, I'm really sorry, I've got some bad news for you-there are no fights from Washington.” So I took my box and put it on the desk and I said: “In this box are some stem cells that are urgently needed for a patient-please, please, you've got to get me back to the United Kingdom.” She just dropped everything. She arranged for a flight on a small plane to be held for mere-routed(改道)me through Newark and got me back to the UK even earlier than originally scheduled.

For thiscourier job, you're consciously aware than that box you're got something that is potentially going to save somebody's life.

    Andy was still traveling in Spain when he realized he had to confirm (确认) his flight home with the airline company (航空公司). He was visiting Spain in order to improve his Spanish. When he was speaking to people face to face, he had no difficulty understanding what they said. However, when he was speaking on the phone, he still had a problem. Andy called the airline. And the clerk confirmed that his plane was leaving at nine o'clock three days from that day. She also told Andy to be at the airport two hours earlier in order to check in his luggage and get a seat.

    Since he was leaving in three days, Andy didn't lose any time. He visited as many places as he could. He thought that it would probably be a while before he had enough money again. He wished he could come back and spend a year in Spain.

    Too quickly, the final day arrived. Andy left early for the airport to arrive two hours before take-off. He hated to rush. He went to the clerk to show his ticket. The clerk looked at the ticket in surprise. "Why, sir, but your flight was at nine o'clock in the morning, and now it is eight in the evening." "But I confirmed my flight," insisted Andy. "Will I have to pay for another ticket?"

    "No, sir. However, the next flight out will be three days from now."

    Andy's look of shock turned to pleasure as he realized that now he could continue his vacation.

    Lost cities that have been found

    The White City

    In 2015, a team of explorers to Honduras in search of “the Lost City of the Monkey God” led to the discovery of the White City. They found the ruins in the Mosquitia region of the Central American country — which is known for poisonous snakes, vicious jaguars and deadly insects. It is believed that local people hid here when the Spanish conquerors(征服者)occupied their homeland in the 16th century.

    Canopus and Heracleion

    Modern researchers were teased by the ancient writings about the Egyptian cities Canopus and Heracleion — where Queen Cleopatra often visited. But the cities weren't found until 1992, when a search in Alexandria waters found that the two cities had been flooded for centuries. Artifacts(史前器物)showed that the cities once highly developed as a trade network, which helped researchers piece together more about the last queen of Egypt.

Machu Picchu

    A Yale professor discovered “the Lost City in the Clouds” in 1911. A combination palaces, plazas, temples and homes, Machu Picchu displays the Inca Empire at the height of its rule. The city, which was abandoned in the 16th century for unknown reasons, was hidden by the local people from the Spanish conquerors for centuries, keeping it so well preserved.

Troy

    The ancient city of Troy in Homer's The Iliad was considered a fictional setting for his characters to run wild. But in 1871, explorations in northwestern Turkey exposed nine ancient cities layered(层叠)on top of each other, the earliest dating back to about 5,000 years before. It was later determined that the sixth or seventh layer contained the lost city of Troy and that it was actually destroyed by an earthquake, not a wooden horse.

    There exist cruel wars, fighting and sadness in the world today, so it's not only necessary, but also essential to have a good sense of humor just to help us go through difficult times in our lives. Putting a smile on someone's face when you know they are feeling depressed, as the saying goes, makes me feel good and warms my heart.

    How would you feel if you could not joke around with wife, husband, child, co-worker, neighbor, close friend, or even just someone that you are standing in line with at your corner store? I am always saying things that make others smile or laugh, even if I don't know the person I'm joking around with. My Grandma always found humor in everything she did, even if it was the hardest job anyone could imagine. This not only relieves stress in any situation, but also is a common manner to speak to others that are around you.

    I know of a few people that don't have a funny bone in their bodies, as they say. Everyone around them could be rolling on the floor after hearing a great joke and they would sit there without the slightest smile on their faces. They don't get the joke that makes others laugh. I am, laughing hard while they just sit there, looking at me as if I were from outer space. How can people not get a really funny joke?

    Laughing is essential to keep your stress levels under control. Without humor, we would find ourselves with a lot of psychological problems, or on a lot of medications to keep us from going crazy. There is too much sadness and bring a little light into our lives. Therefore, I believe our best medicine is to get together and tell some jokes and have some fun laughing together.

    Why do we dream? It's a question researchers have been studying for years. Now new research suggests that some dreams may result from the brain's effort to keep learning, even as we sleep.

In a study in Boston,100 volunteers were trained for an hour on a maze(迷宫). They tried to find their way through the difficult puzzle as quickly as possible. Then half of the volunteers were allowed to sleep for 90 minutes. The other half stayed awake, reading or relaxing. The ones who slept were asked to describe their dreams when they woke up.

    After the rest, the volunteers were asked again to solve the maze. Those who hadn't slept showed no improvement or did even worse after the break. Sleepers who didn't report any maze­related dreams did better but showed only a little improvement. However, four nap­takers who reported dreaming about the maze showed a surprising improvement. They scored 10 times higher after sleeping and dreaming about the maze.

    Even though the number of dreamers was small, the researchers noted that the gap in learning between the dreamers and non­dreamers was so wide that the finding was significant(有意义的).

The dreamers had all performed poorly on the test before dreaming about it. That suggests that struggling with a task might be the trigger that leads the sleeping brain to focus on it and work on how to deal with it.

    "It's almost as if your brain is going through everything that happened today," Dr Stickgold, a scientist at Harvard Medical School, said. "The things you're obsessed(迷住) with are the ones that your brain forces you to continue to do with."

    Millions of Americans are living in areas at high-risk of river flooding, many of whom are completely unaware of the danger.

    While the risk of coastal flooding from extreme storms and rising seas rightly attracts plenty of attention, Americans are being urged to look inland for a similar threat receiving far less recognition: river flooding. New research conducted by the University of Bristol has shown that as many as 41 million Americans are highly at risk from river floods – more than three times the number previously estimated – with real estate (住宅区) in areas such as Louisiana, Florida, Arizona and West Virginia found to be especially at threat.

    For the first time, it has been possible to produce super quality flood risk maps that cover the whole United States, while previous Federal Emergency Management Agency (FEMA) flood maps cover no more than 60 per cent of the country. The fine details provided by these new maps also makes it possible to predict the powerful effects of flooding on many smaller streams than before, thus raising concerns about the increasing number of people potentially threatened.

    "We were all surprised by how many Americans we find are exposed to flooding from rivers," says Oliver Wing, from the University of Bristol's School of Geographical Sciences. "It's particularly worrisome considering that most of these people aren't even aware of the risk they face."

    Additionally, there is the possibility that this lack of awareness means construction in high-risk river flooding areas will continue to rise, despite the threats. Estimates (估量) suggest that projected population growth, continued urbanization trends (城市化趋势), and the unpredictable threats caused by climate change will leave over 60 million Americans vulnerable (易受攻击的) to a 100-year flood by the middle of the century. 'All of this highlights the urgent need for large areas of floodplain and flood risk management planning,' adds Wing.