In the frozen continent of Antarctica scientists fear an alien invasion — not from outer space, but carried in people's pockets and bags.

    Seeds and plants accidentally brought to Antarctica by tourists and scientists may introduce alien plant species which could threaten the survival of native plants in the finely balanced ecosystem.

    “The people that were carrying the most had lots and lots of seeds. They really were real threats,” said Dana Bergstrom, from the Australian Antarctic Division.

    “When we take things in through hitchhiking（搭车旅行） then we get species which are competitive. The plants and animals there are not necessarily competitive, so we'd start losing various precious biodiversity（生物多样性） on the (Antarctic) continent”, Bergstrom told Reuters.

    Amongst the alien species discovered were the Iceland Poppy, and Annual Winter Grass — all from cold climates and capable of growing in Antarctica.

    The Antarctic Peninsula, where most tourists travel, is now considered a “hot spot” on the frozen continent and the warmer the climate, the easier for seeds to grow. “The peninsula(半岛) is warming at some of the greatest rates on the planet,” said Bergstrom.

    The study, the first continent-wide assessment of invasive species in Antarctica, surveyed about 1,000 passengers during 2007-2008, the first year of the International Polar Year, an international effort to research the polar areas.

    Bergstrom said the one alien seed that had gained a foothold is Annual Winter Grass. It is a strong weed in the sub-Antarctic and is on the Antarctic island of King George. It has also made its way to the tail part of the Antarctic continent.

    I live in the land of Disney, Hollywood. You may think people in such an attractive and exciting, fun-filled place are happier than others. If so, you have some mistaken ideas about the nature of happiness.

    Many intelligent people still consider happiness equal to fun. The truth is that fun and happiness have little or nothing in common. Fun is what we experience during an act. Happiness is what we experience after an act. It is a deeper, more lasting emotion.

    Going to an amusement park or ball game, watching a movie or television, are fun activities that help us relax, temporarily forget our problems and maybe even laugh. But they do not bring happiness, because their positive effects end when the fun ends.

    I have often thought that if Hollywood stars have a role to play, it is to teach us that happiness has nothing to do with fun. These rich, beautiful people have constant access to glamorous parties, fancy cars, expensive homes, everything that brings “happiness”. But in memoir after memoir, famous people expose the unhappiness hidden beneath all their fun — depression, alcoholism, drug addiction, broken marriages, troubled children and extreme loneliness.

    Ask an unmarried man why he refuses to get married even though he finds dating to be less and less satisfying. If he's honest, he will tell you that he is afraid of making a commitment. For commitment is in fact quite painful. The single life is filled with fun, adventure and excitement. Marriage has such moments, but they are not its most distinguishing features.

    Similarly, couples that choose not to have children are deciding in favor of painless fun over painful happiness. They can dine out whenever they want and sleep as late as they want. Couples with babies are lucky to get a whole night's sleep or a three-day vacation. I don't know any parent who would choose the word fun to describe raising children.

    The way people stick to the belief that a fun-filled, pain-free life equals happiness actually reduces their chances of ever achieving real happiness. If fun and pleasure are equal to happiness, then pain must be equal to unhappiness. As a result, they fear the pain unavoidably brought by such things as marriage, raising children, professional achievement, religious commitment and self-improvement.

    But, in fact, the opposite is true. More times than not, things that lead to happiness involve some pain. The very efforts are the source of true happiness. Understanding and accepting that true happiness has nothing to do with fun is one of the most liberating realizations we can ever come to.

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    Living and dealing with kids can be a difficult job these days, but living and dealing with parents can be even more complex.

    If I have learned anything in my 16 years, it is that communication is very important. With any relationship, you need to let other people know how you are feeling. If you are not able to communicate, you drift apart (疏远). When you are mad at your parents, or anyone else, not talking to them doesn't solve anything.

    Communication begins with the concerns of others. It means that you can't just come home from school, go up to your room and ignore everyone. To keep a good relationship, you must keep communication, even if it's just by writing a note.

    When dealing with parents, you always have to make them feel good about how they are doing as a parent. If you are trying to make them see something as you see it, tell them that you'll listen to what they have to say, but ask them politely to listen to you. Yelling or walking away only makes the situation worse.

    This is an example: one night, Sophie went to a street party with her friends. She knew she had to be home by midnight after the fireworks, but she didn't. She was late getting home. Her parents were mad at first, not giving Sophie a chance to explain why she was late. Later, they kept calm and listened to her. Communication is the key factor here. If Sophie's parents had not been willing to listen, Sophie would have been in a lot of trouble.

    Barbara McCintock was one of the most important scientists of the twentieth century. She made important discoveries about genes(基因) and chromosomes (染色体).

    Barbara McClintock was born in 1902 in Hartford, Connecticut. Her family moved to Brooklyn area of new York City in 1908.Barbara was an active child with interests in sports and music. She also developed an interest in science.

    She studied science at Cornell University in Ithaca, New York. Barbara was among a small number of undergraduate students to receive training in genetics in 1921. Years later, she noted that few college students wanted to study genetics.

    Barbara McClintock decided to study botany, the scientific study of plants, at Cornell University. She completed her undergraduate studies in 1923. McClintock decided to continue her education at Cornell. She completed a master's degree in 1925. Two years later, she finished all her requirements for a doctorate degree.

    McCintock stayed at Cornell after she completed her education. She taught students botany. The 1930s were not a good time to be a young scientist in the United States. The country was in the middle of the great economic Depression. Millions of Americans were unemployed. Male scientists were offered jobs. But female geneticists were not much in demand.

    An old friend from Cornell, Marcus Rhoades, invited McClintock to spend the summer of 1941 working at the Cold Spring Harbor Laboratory. It is a research center on Long Island, near New York City. McClintock started in a temporary (临时的) job with the genetics department. A short time later, she accepted a permanent (永久的) position with the laboratory. This gave her the freedom to continue her research without having to teach or repeatedly ask for financial aid.

    By the 1970s, her discoveries had had an effect on everything from genetic engineering to cancer research. McClintock won the Nobel Prize for Physiology or Medicine in 1983 for her discovery of the ability of genes to change positions on chromosomes. She was the first American woman to win an unshared Nobel Prize.

    A year back I received a full scholarship (奖学金) to attend the University of San Francisco. All of my hard work paid off. My mom had spent a lot on my attending a private high school, so I made sure to push myself: I volunteered, took part in various clubs, and graduated with honors. I was so excited to start a new part of my life.

    Soon enough, the big day came, but it wasn't like what I had thought. The first two weeks were the most difficult days of my entire life. Every night I would cry myself to sleep. I was missing my family, my home and everything in my hometown so much and I didn't know how to deal with my broken heart.

    To distract myself, I threw myself into my studies. I also found a ton of jobs. In any free time, I started forcing myself to go to the gym. I wanted to keep every part of my day busy so I wouldn't think about how lonely I felt. Soon after, I began to control my eating, considering it another solution to my homesickness(想家). But soon there was something wrong with me.

    Finally, I went to see a doctor. When the doctor told me I had no choice but to take time away from school, I started to fear. How could I stop? School was what I was best at. "I'm not so bad," I thought in my head. But the result was that I was taken to hospital again a month later and my mother came heartbrokenly. I had to take a semester off from school, and go to the treatment center near my home.

    If there are girls who are suffering similarly, I hope you know that there is hope and that you should have a positive attitude towards life. Though you may feel alone, there are so many people who can understand your struggle. That's why I want to share my story.

Hot Technology Products at CES 2020

The consumer electronics show, or CES, presents new technology developments annually. Here are some latest products launched at CES 2020.

The Sero TV

Samsung introduced a TV that can be used to watch video designed for a smartphone. The Sero TV does this by turning itself from the normal TV position to an upright position that looks like the shape of a phone. The V can connect to mobile devices to play video directly from the phone.

Smart waste can

A company called TOWNEW presented; waste can designed for the home that does a lot of the dirty work on its own. When the can is full, the user touches a button to activate the machine's smart abilities. The device then completely closes off the waste bag inside, puts a new one in place, all by itself, and raises its top so the user can pick up and throw away the bag.

Invisible car hood(引擎盖)

Automobile industry company Continental showed off a new technology that seems to make the front end of a vehicle disappear. The technology, called "Transparent Hood," aims to make driving safer and easier. Cameras provide video of the area underneath the vehicle, permitting the driver to see objects and road conditions that might present danger.

Wearable air purifier

A company called Aō Air introduced a wearable air purifier. Designed to be a high-tech face covering to block pollution, the device pulls air through a filtration(过滤)system and then uses fans to create a small area of clean air at its front, allowing the air to be purified-without the need for a solid container.