Do you believe that things are connected for no scientific reason at all? For example, do you avoid saying the word "four" to avoid bad luck? If so, you have a superstition (迷信). And you're not alone – all kinds of people have them.

For example, Portugal's soccer superstar Cristiano Ronaldo always steps onto the pitch (球场) with his right foot first, according to The Telegraph. And sports players are not alone in having superstitions. A visitor once asked the Nobel Prize winning scientist Niels Bohr whether he really believed that the horseshoe he'd hung at his country home was lucky. "Of course not," the Danish physicist said. "But I understand it's lucky whether you believe in it or not."

One recent study found that even scientists at MIT and other top US schools tended to look for a meaning in natural events, similar to the connection between stepping on the pitch and playing soccer well, according to The Atlantic. When the researchers gave the scientists little time to answer questions, they were twice as likely to agree with statements such as "Trees produce oxygen so that animals can breathe" as they were when they had more time to think about their reply.

It seems that fear can make people think differently in this way, too. In a British study, students imagined meeting a "witch" who said she would cast (施魔法) an evil spell(符咒) on them. About half said a scientist should not be worried about the spell. Yet each of them said that, personally, they wouldn't let the witch do it to them.

So why are so many of us superstitious? Well, it seems to be our way of dealing with the unknown. "Many people quite simply just want to believe," Brian Crank, a professor of psychology at Missouri Western State University, said in a 2008 interview. "The human brain is always trying to work out why things happen, and when the reason is not clear, we tend to make up some pretty bizarre (古怪的) explanations."

    And these explanations aren't completely unhelpful. In fact, superstitions can sometimes work and bring real luck, according to psychologists at the University of Cologne in Germany in the May 2010 issue of the journal Psychological Science. They found that believing in something can improve performance on a task like an exam.

    So, what about you? What superstitions do you follow to keep you safe and successful?

    Here's an idea whose time has come: A flu shot that doesn't require an actual shot.

    For the first time, researchers have tested a flu vaccine patch (疫苗贴) in a human clinical trial and found that it delivered as much protection as a traditional injection with a needle. Doctors and public health experts have high hopes that it will increase the number of people who get immunized (免疫的) against the flu.

    Seasonal flu is responsible for up to half a million deaths around the world each year according to the World Health Organization. A team led by Georgia Tech engineer Mark Prausnitz has come up with an alternative method that uses “microneedles”. These tiny needles are so small that 100 of them, arranged in order on a patch, can fit under your thumb (拇指).Yet they're big enough to hold vaccine for three types of flu.

    None of the study volunteers had serious side effects. The groups that got patches had mild skin reactions that were not seen in the regular needle group, while the volunteers in the regular needle group were more likely to experience pain. Overall, 70 percent of the volunteers who got vaccine patches said they'd rather use them again than get a traditional flu shot. The study authors declared it a success on all fronts.

    The biggest beneficiaries could be people in low- and middle-income countries, where flu vaccines are hard to come by. Reducing pain is nice, but other benefits—the patch costs less，is easier to transport, doesn't require refrigeration, can be self - administered and doesn't cause waste of needles—are even better.

    “Microneedle Patches have the potential to become ideal candidates for vaccination programs,” wrote Katja Hoschler and Maria Zambon of Public Health England.

    One day a few years ago, a very funny thing happened to a neighbour of mine. He is a teacher at one of London's big medical schools. He had finished his teaching for the summer term and was at the airport on his way to Russia to give a lecture.

    He had put a few clothes and his lecture notes in his shoulder bag , and he had put Rupert , the skeleton (人体骨架）to be used in his lecture , in a large brown suitcase. At the airport desk, he suddenly thought that he had forgotten to buy a newspaper. He left his suitcase near the desk and went over to the shop.

    When he got back he discovered that someone had taken his suitcase by mistake. He often wonders what they said when they got home and found Rupert.

    "When your mother scolds you, you can look elsewhere and think about other things. Just ignore her words. But remember: such a tough attitude cannot be used often." These words are from a series of cartoons which outline skills for children to fight against their mothers. The images have created heated debate among Chinese netizens (网民).

    Regarded as "a book for children aged 6 to 12 who are always scolded by their parents", the cartoons, drawn by two 10-year-old Beijing girls, list over 20 skills which children can use to deal with their mothers' anger such as crying, pretending to be ashamed, fleeing into the toilet and pleasing her afterwards. Each skill is described with vivid pictures and humorous notes. The creativity of the young girls has amazed netizens, the Yangtse Evening Post reported on Thursday.

    According to one of the girls' mothers, her daughter once received a poor mark in an exam, and the mother blamed her and compared her performance with another classmate. The daughter's feelings led to her creating the cartoons. The girl's father, who first posted the pictures on his Sohu Microblog on Monday, said he hopes parents pay close attention to the pictures, allow children to feel free to develop their own characteristics and try not to criticize them so often.

    "The cartoons, although an individual case, reflect a modern phenomenon and some of the problems within Chinese family education," said Yu Qinfang, an expert on family education. According to a survey of 104 children and their parents, Yu discovered that as many as 51.9 percent of primary school students hate being urged to do things by their mothers. "Not giving children enough time and hurrying them to do things seems to be a very tiny detail within family life, but it is potentially a huge problem which can easily be ignored by parents. A mother's blame may lead to negative feelings within her child's heart," Yu said. "Parents should learn to blame less and be more patient."

    A single dose(剂量) of an experimental vaccine(疫苗) can protect mice against the Zika(寨卡) virus, raising renewed hope of a vaccine for humans, say scientists. The US team say the results, published in Nature, are "striking" and should encourage research efforts.

    Tests in humans could begin in months. But even if these go well, a licensed vaccine for widespread use to protect those at most risk ­ such as pregnant women ­ would still be years away, experts advise. Zika has been spreading across Central and South America and, most recently, Africa. More than 60 countries and territories now have continuing transmission(传播) of the disease, which is carried by mosquitoes. The virus causes serious birth damages during pregnancy and has been declared a global public health emergency.

    Now, developing a vaccine for pregnant women to protect their unborn babies is an international research priority(优先事项). US scientists from the Walter Reed Army Institute of Research, the Beth Israel Deaconess Medical Center and Harvard Medical School tested two types of Zika vaccine in mice – one based on bits of genetic(基因的) code from the virus and another that is an inactive (and therefore harmless) copy of Zika. Both worked well, protecting every mouse that was immunised against the virus. In comparison, all of the mice not given the vaccine caught Zika after they were exposed to it.

    Researchers say they will push ahead with developing the needed virus vaccine. There are many existing vaccines for other disease that use this type of technology, while there are relatively few DNA­based vaccines. Of course, future tests will need to check the vaccine is safe and effective in humans, as well as how long the immunity might last.