The sound of a mosquito can mean trouble in many parts of the world. The bite of the mosquito can be deadly. The insects carry serious diseases like malaria (疟疾). It is estimated that almost 630,000 people died from malaria and malaria­related causes in 2012, and most of these cases were in African countries.

    In the United States, a group of California scientists are working to develop a more effective and less costly substance (物质) to protect people from mosquitoes. The researchers are investigating the sense of smell in mosquitoes. They found the insects use the same receptor for identifying carbon dioxide in human breath as they do for the smell of our skin. Anandasankar Ray, who is leading the investigation, says scientists tested more than a million chemical compounds (化合物) until they found a substance called Ethyl Pyruvate. He says Ethyl Pyruvate makes the mosquitoes' receptors inactive. “When we apply Ethyl Pyruvate to a human arm and offer it to hungry mosquitoes in a cage, very few of the mosquitoes are attracted to the human arm because only a few of them are able to smell it out,” said Ray.

    Genevieve Tauxe, a member of the research team, says it was not easy to find the neurons (神经元) of noble cells that recognize both the smell of human breath and skin. “With the device used to examine the mosquito, we are able to insert a very small electrode (电极) into the part of the mosquito's nose, where its smelling neurons are and where the smell is happening,” said Tauxe.

    Anandasankar Ray says a product based on Ethyl Pyruvate may cost less to produce than DEFT, the most effective chemical treatment now in use. He says DEFT is too costly for most people who live in areas affected by malaria.

    “Perhaps by finding smells that can attack other target receptors, we will be able to improve upon DEFT and finally have the next generation of insect behaviour control products,” said Ray.

    If you have ever been left wondering why your emails are riddled(充斥着) with grammatical errors, or why you can never quite find the right phrase, it may be because you are typing with both hands.

    Our vocabulary becomes richer and our writing style becomes more fluent when we type using just one hand, scientists have found. "Typing can be too fluent or too fast, and it can actually weaken the writing process," said Srdan Medimorec, the lead author of the study conducted at the department of psychology at the University of Waterloo, Canada. "It seems that what we write is a product of the interaction(互动) between our thoughts and the tools we use to express them."

    Using text-analysis software, researchers asked 103 university students to write essays under different conditions, using one hand to type and using both hands to type. The software was used to analyze(分析) elements of the essays, such as range of vocabulary, sentence complexity and the cohesion(衔接) of the writing.

    Researchers found that participants' vocabulary became more advanced when they typed with one hand rather than two. The research team said that by slowing our writing down, typing one-handed allows more time for an internal (内在的) word search, resulting in a larger variety of words.

    In contrast, fast typists might just write the first word that comes to mind. However, it is important not to slow typing down too much. Those who typed essays one-handed in the current study slowed down to about the speed of handwriting.

    This is the first study to show that changing people's typing can make their writing get better. The researchers suggested that the speed of writing could affect writing quality regardless of the tools used, whether they are computers, or pen and paper, although further research would be required to prove that idea.

    It is quite reasonable to blame traffic jams, the cost of gas and the great speed of modern life, but manners on the road are becoming horrible. Everybody knows that the nicest man would become fierce tigers behind the wheel. It is all right to have a tiger in a cage, but to have one in the driver's seat is another matter.

    Road politeness is not only good manners, but good sense. It takes the most cool-hearted drivers great patience to give up the desire to beat back when forced to face rude driving. On the other hand, a little politeness goes a long way towards reducing the possibility of quarrelling and fighting. A friendly nod or a wave, or thanks in answer to an act of politeness helps to create an atmosphere of good will and becomes so necessary in modern traffic conditions. But such behaviors of politeness are by no means enough. Many drivers nowadays don't even seem able to recognize politeness when they see it.

    However, misplaced politeness can also be dangerous. Typical example is the driver who waves to a child crossing the street at a wrong place into the path of oncoming cars that may not be able to stop in time. The same goes for encouraging old ladies to cross the road wherever and whenever they want to.

    An experienced driver, whose manners are faultless, told me it would help if drivers learnt to correctly join in traffic stream without causing total jams that give rise to unpleasant feelings. Unfortunately, modern drivers can't even learn to drive, let alone master the roadmanship(驾车技能). Years ago, experts warned us that the fast increase of the car ownership would demand more give-and-take from all road users. It is high time that all of us took this message to heart.

    Many Americans think of driverless cars as a futuristic technology that will revolutionize travel in cities and along state highways. But recent experiments are proving that autonomous vehicles also have the potential to improve the quality of life for millions of Americans underserved by traditional modes of transportation, such as the elderly and disabled, so long as lawmakers make smart policies that pave the way for innovation.

    A retirement community in San Jose, Calif. , which has been transformed by a small fleet of driverless taxis, shows the potential of self-driving cars to transform people's lives. Built by a tech start-up called Voyage, the modified Ford Fusions are currently limited to a two-mile road, but residents are already having the benefits of these autonomous vehicles, which allow them to participate in social activities they would otherwise be unable to enjoy simply because they could not get to them.

    When the trial run finally expands to 15 miles of road, these residents—whose average age is 76—will also have a convenient and reliable new way to appointments. As these cars continue to serve residents there, it is easy to understand why California is moving to simplify regulations for the industry.

    In Michigan, forward-thinking policies have the potential to unlock other hidden benefits of autonomous vehicles, especially for those with physical disabilities. The Michigan Disability Rights Coalition has strongly advocated for the development of this technology, saying that it could give people with disabilities greater opportunities in the workforce and enable them to lead more fulfilling, independent lives.

    Many recognize that autonomous vehicles will be the future of transportation, but it is too often overlooked that this future cannot arrive fast enough for millions of Americans who are forced to depend on others for day-to-day travel. The policymakers should follow the lead of places like California and Michigan, and pass rules and regulations to unlock these hidden benefits of driverless cars.

    The theatre in Shakespeare's time was much different than it is today. Authors wrote plays for the masses, especially those who couldn't read or write.

    The theatre changed a lot during Shakespeare's lifetime. The authorities didn't like it and didn't allow acting in the city itself: They thought it had a bad influence on people and kept them from going to church. Queen Elizabeth, on the other hand, loved acting and helped the theatre become popular.

    The theatre in Shakespeare's time was full of life. People did not sit all the time and it was not quiet during the performance. The audience could walk around, eat and drink during the play.

    Theaters were open arenas or playhouses that had room for up to three thousand people. There was almost no scenery because the dialogue was the most important part of the play. Colourful and well-designed costumes were very important and told the people about the status of a character. Women never performed in plays, 80 young boys played female characters. The performances took place in the afternoon because it was too dark at night.

    There was no stage crew as there is today. Actors had to do everything themselves-from making costumes to setting the stage. Plays were organized by acting companies. They performed about 6 different plays each week because they needed money to survive. They had almost no time to rehearse (排练).

    The companies in Shakespeare's time had a rank system. The company belonged to shareholders and managers. They were responsible for everything and got most of the money when the company was successful. Sometimes they even owned their own buildings. Actors worked for the managers and after some time became a permanent member of the company. Apprentices (学徒) were young boys and were allowed to act in unimportant role. They also played female characters in plays.

    A primary school in UK has banned Valentine's Day cards because of concerns that young pupils spend too much time talking about boyfriends and girlfriends.

    Ashcombe Primary School in Weston Super Mare, Somerset, has told parents that cards declaring love can be "confusing" for children under the age of 11, who are still emotionally and socially developing. In this month 's newsletter(通讯), Peter Turner, the head teacher, warned that any cards found in school would be confiscated(没收). He wrote: "We do not wish to see any Valentine's Day cards in school this year. Some children and parents encourage a lot of talk about boyfriends and girlfriends. We believe that such ideas should wait until children are mature enough emotionally and socially to understand the commitment involved in having or being a boyfriend or girlfriend." Mr. Turner said any family wanting to support the Valentine's Day idea should send cards in the post or deliver them to home addresses by hand.

    His views were endorsed by Ruth Rice, 46, who has twins Harriet and Olivia at the school. She said, "Children at that age shouldn't really be thinking about Valentine's Day, they should be concentrating on their schoolwork." They are at an age when they are impressionable(易受影响的)and most parents including myself are with Mr. Turner." She added that "the cards cause too much competition. If someone gets a card and another doesn't, then someone will be disappointed."

    However, Rajeev Takyar, 40, who has two children Jai, 11, and Aryan, five, at the school, said he was "very angry". He said, "There are schools that have banned computer games and snowballs, and now Valentine's Cards." I think banning the cards stops children from having social skills. How are they going to learn about relationships otherwise? It's ridiculous. Alec Suttenwood, father of three children, said of the ban: "It's totally ridiculous. Young children just send the cards to each other as friends and to their parents. It's just a bit of harmless fun. There is no difference between this and Mother's or Father's Day."