Most people know that Marie Curie was the first woman to win the Nobel Prize, and the first person to win it twice. However, few people know that she was also the mother of a Nobel Prize winner.

    Born in September, 1987, Irene Curie was the first of the Curies' two daughters. Along with nine other children the parents of whom were also famous scholars, Irene studied in their own school, and her mother was one of the teachers. She finished her high school education at the College of Sévigné in Paris.

    Irene entered the University of Paris in 1914 to prepare for a degree in mathematics and physics. When World War I began, Irene went to help her mother, who was using X-ray facilities (设备) to help save the lives of wounded soldiers. Irene continued the work by developing X-ray facilities in military hospitals in France and Belgium. Her services were recognised in the form of a Military's Medal by the French government.

    In 1918, Irene became her mother's assistant at the Curie Institute. In December 1924, Frederic Joliot joined the Institute, and Irene taught him the techniques required for his work. They soon fell in love and were married in 1926. Their daughter Helene was born in 1927 and their son Pierre five years later.

    Like her mother, Irene combined family and career. Like her mother, Irene was awarded a Nobel Prize, along with her husband, in 1935. Unfortunately, also like her mother, she developed leukemia because of her work with radioactivity (辐射能). Irene Joliot-Curie died from leukemia on March 17, 1956.

    While beach vacations may be a great way to take your mind off work，lakes surrounded by mountains make for an even grander experience．If you are looking for some peace on your vacation，we have some recommendations for you in the Caucasus(高加索)．

Lake Sevan

    Lake Sevan is situated in the central part of Armenia，in the Gegharkunik province．It is the largest lake in Armenia，located 6,200ft above sea level．Along the lake shore，there are various accommodations such as resorts and hotels with plenty of activities to partake in such as windsurfing，swimming and sunbathing．While there，do not forget to visit one of the famous cultural monuments，the Sevanavank Monastery，and it offers a great view of the lake as well．

Lake Paravani

    Lake Paravani，located at 6,801ft above sea level，is in the south of Georgia，near the Javakheti plateau．At this level，altitude sickness can occur and it is a good idea to be prepared to adapt to it properly，or bring medication for altitude sickness．Being a volcanic lake makes for a more interesting experience．The lake is best known for fishing．Do not come home during the winter months when the lake freezes．

Lake Cildir

    Lake Cildir is located in the Ardahan province，East Turkey，near the borders of Georgia and Armenia．It is the second largest freshwater lake of Eastern Turkey，and many tourists are not aware of this beautiful attraction．Lake Cildir is surrounded by mountains of the Caucasus．The lake freezes during late November．If the winter is not extremely cold，you can try some lake activities like ice skating and ice fishing．

Lake Van

    Lake Van is the must visit of all lakes in this list．The largest lake in Turkey，Lake Van is located on the eastern shore of Turkey and is also the most accessible lake here．It's situated at 5，380ft above sea level，and unique to lakes around the world，the water is high in salt content．

    On a recent afternoon, some 60 years after they graduated from grammar school, Kathleen Rys, 72, and her sister Lorraine O'Kelly, 70, sat down and had a meal with a classmate, Bruce Smit, 71 for the first time.

    In the 1950s, Lorraine and Kathleen Rys' family moved from Chicago to Monee. As new kids at Monee Elementary School, they soon found themselves on the outs with other students.

    "I would be with the other guys and see Kathleen walking down the hallway, her head down, holding her books, walking slowly. And all of us guys would be flat against the wall until she passed. Then we'd burst into laughter. How rude is that? It's just crazy." said Smit, a doctor whose wife, Tammy, organized the meeting.

    The women said none of the teachers cared about it. "We just kept it to ourselves. " Lorraine said.

    Over the years, Tammy Smit said, "Bruce would just start to cry at times. He'd wonder what happened to the sisters, if they landed OK." One day a few weeks ago, Tammy took to the internet and found Mary O'Kelly, Lorraine's daughter, and offered to set up a meeting. The idea of revisiting the pain was not well- received by Kathleen, who had never married, let alone gone on a date. It took some convincing, but Lorraine finally got Kathleen to agree to meet with Bruce.

    Bruce broke into tears. "I'm so ashamed, so embarrassed," he said. "But I'm so happy you're still here and that I can finally apologize. " He said he hopes his apology will encourage others to seek forgiveness for the pain they make on others. Lorraine said, "This is a beautiful thing. It's just wonderful that a person from 60 years ago can ask for forgiveness. It's like a miracle to us. It's a healing to us."

    The first organized system for sending messages began in Egypt around 1500 B.C. This system developed because the pharaohs frequently needed to send messages up and down the Nile River in order to keep their empire running smoothly. Later, the Persians developed a more efficient system for sending messages using men and horses. Messages carriers rode along the road system stretching from one end of the Persian Empire to the other. Along these roads, fresh men and horses waited at special stations to take and pass along any messages that needed to be sent. The stations where riders passed messages back and forth were built 23 kilometers apart, so the men and horses were able to travel quickly between them. The Romans later took up his idea and improved it by using a more advanced and extensive road system.

    In China, however, Kublai Khan had built up his own system for delivering messages. This system worked in the same basic way as the Roman system. The difference was that Kublai Khan kept 300,000 horses along the roads of this delivery lines. There were over 10,000 stations where a message would be passed from one rider to another with a fresh horse. In this way, Kublai Khan could receive messages from anywhere in the country in only a few days.

    It was not until the 1500s that a well-organized postal system appeared again in Europe. One family, the von Taxis family, gained the right to deliver mail for the Holy Roman Empire and parts of Spain. This family continued to carry mail, both government and private, throughout Europe for almost 300 years.

    In 1653, a Frenchman, Renouard de Velayer, established a system for delivering post in Paris. Postal charges at that time were paid by the recipient, but de Velayer's system was unique by allowing the sender to pre-pay the charges, in a similar way to the modern stamp. Unfortunately, de Velayer's system came to an end when jealous competitors put live mice in his letter boxes, ruining his business. Eventually, government-controlled postal systems took over from private postal businesses, and by the 1700s government ownership of most postal systems in Europe was an accepted fact of life.

    The thing that all these early systems had in common was that they were quite expensive for public use, and were intended for use by the government and the wealthy. However, in 1840, a British schoolteacher named Roland Hill suggested introducing postage stamps, and a postal rate based on weight. This resulted in lowering postal rates, encouraging more people to use the system to stay in touch with each other, His idea helped the British postal system begin to earn profits as early as 1850. Soon after that many other countries took up Mr. Hill's idea. And letter writing became accessible to anyone who could write. Today, the Roland Hill awards are given each year to "encourage and reward fresh ideas which help promote philately"(stamp collecting).

    My name is Kobus Vermeulen. On February 16, 2015, I was one of five South Africans among the 100 people selected by Mars One to begin training to live on the Red Planet. The Dutch not-for-profit's aim is simple: build a human colony (殖民地) on Mars. Since I have begun this journey, the one question that people ask me most is why I want to leave a good planet for wasteland. Here is why.

    I have been interested in Mars since I was a child, and I always thought that if I had the opportunity to leave the planet, I would take it. So the why begins with a child's dream.

    However, as I grew, so did the why. In my eyes, since the 1970s the public has stopped trying to learn more about space. We've put our dream aside. We're satisfied with getting our dose (一份) of the future from sci-fi movies and comic books. And so the first part of my motivation (动机) is to get people thinking about space travel and the colonization (殖民化) of other planets in real terms again instead of just as sci-fi visions of the future.

    If we want that future, the truth is that we have to build it, and anything worth doing comes with risks. Somebody has to take the risks, and I, along with thousands of other people, am willing to take them.

    But it goes deeper than that. If the task of Mars One is even partially (部分地) successful, it will encourage a new generation of scientists and engineers that will build us an even better future.

    Without a dream, there is no reason to build those things. The public that does not try to understand science and technology does not choose good leaders. Leaders who don't care for science and technology do not make budgets (预算) for it. Besides, without the money, the dream dies. Projects like Mars One are like a focusing lens (聚焦透镜) for dreams. It is an opportunity to change hearts and minds at the grassroots level.

    Dr. John Wilkins was a natural philosopher who lived from 1614 until 1672. He was crazy about getting to the moon and meeting the people who surely lived there. Wilkins believed that anything as Earth-like as the moon must have been created by God for living beings, and he was determined to meet them — despite the fact that he was three centuries ahead of his time.

    In the 1600s, the scientific understanding of gravity and outer space was limited. Wilkins believed, like many 17th-century scientists, that there was no difference between the atmosphere of Earth and the conditions in space, and that Earth's pull was due to magnetism (磁力). It was only reasonable, then, that Wilkins believed a two-wheeled horse-drawn battle car with wings with enough speed could lift high enough off the ground to break free of Earth's magnetic pull and reach the moon.

    Then Wilkins moved on to more pressing issues with his remarkable ability to think of new ideas: How would travelers feed themselves during the journey? He theorized that the main cause of hunger was simply the act of working against gravity, so getting to the moon without being burdened by it would be able to be realized. There was some knowledge at that time about the fact that air gets thinner and colder the higher up you go, but he had a fix for that too, "moistened sponges (湿润的海绵) might help us against its thinness".

    By studying the way in which birds fly, which also happened to be part of the studies that led to planes and rockets centuries later, Wilkins put his theory to the test with the help of a colleague, Robert Hooke. Neither of the two ever recorded their attempts, but it's somewhat safe to say that it didn't work out. Hooke himself may have been the reason he gave up hope, in fact, since he was part of the team that discovered space was a place without oxygen.