Car companies are developing vehicles that will plug into electric sockets, ust like many laptops, digital cameras, cell phones and Mp4 do. Called “plug-in vehicles”, these cars will get most of their power from electricity. Their drivers won't have to stop at gas stations as often as usual.

    The technology is more than just cool. In our car-filled world, plug-in vehicles could reduce the amount of gas we use, which keeps rising in cost now and then. Besides, driving around in these vehicles may even help the environment. Gas-burning cars produce a lot of greenhouse gas, which causes global warming.

    The first company-produced plug-in vehicles could hit the roads by 2020. But engineers still have a lot of work to do to make the technology practical and inexpensive.

    Batteries are the biggest challenge. In the plug-in-vehicle world，Li-ion(锂离子)batteries are getting the most attention. These batteries can store a large amount of energy in a small package, and they last a longer time between charges. Li-ion batteries can fit laptops, cell phones, heart instruments and other similar pocket ones.

    But because cars are so big and heavy, it would still require a suitcase-sized Li-ion batteries to power about 12km of driving. What's more, the batteries are much expensive.

    “A car filled with batteries could go a long distance,” says Ted Bohn, an electrical engineer in Chicago. “But it couldn't pull any people, and it would cost $100,000.” So researchers need to work out how to make batteries smaller and cheaper, among other questions.

    “The answers don't exist yet,” Bohn says, “As a kid, I thought someone someplace knows the answer to everything. All of these questions haven't been decided. That's what engineering is about-making a guess, running tests and getting fine results.”

    By trying to tickle(挠痒痒) rats and recording how their nerve cells respond, Shimpei Ishiyama and his adviser are discovering a mystery that has puzzled thinkers since Aristotle expected that humans, given their thin skin and unique ability to laugh, were the only ticklish animals.

    It turns out that Aristotle was wrong. In their study published on Thursday, Ishiyama and his adviser Michael Brecht found that rats squeaked and jumped with pleasure when tickled on their backs and bellies. These signs of joy changed according to their moods. And for the first time, they discovered a special group of nerve cells. These nerve cells made this feeling so powerful that it causes an individual being tickled to lose control.

    To make sure that he had indeed found a place in the brain where tickling was processed, Ishiyama then stimulated that area with electrical currents. The rats began to jump like rabbits and sing like birds.

    “It's truly ground-breaking,” said Jeffrey Burgdorf, a neuroscientist at Northwestern University who reviewed the paper. “It takes the study of emotion to a new level.”

    Burgdorf has played a central role in our understanding of animal tickling. He was part of a team that first noticed, in the late 1990s, that rats made special noises when they were experiencing social pleasure. Others had already noted that rats repeatedly made short and high sounds during meals. But the lab where Burgdorf worked noticed that they emitted similar sounds while playing. And so one day, the senior scientist in the lab said, “Let's go and tickle some rats.” They quickly found that those cries of pleasure doubled.

    “The authors have been very adventurous,” said Daniel O'Connor, a neuroscientist at Johns Hopkins University who studies touch. To him, that finding was very surprising.

    “Why does the world literally feel different when you are stressed out?” he said. “This is the first step towards answering that question. It gives us a way to approach it with experimental rigor(严谨).”

    Companion planting is the idea that some kinds of plants can help each other grow. Plants that are compatible (兼容的，能共处的) together generally have similar needs in terms of nutrients, soil and moisture levels.

    Advice about which plants are compatible is sometimes based more on tradition than proof. But experts say there is evidence to support certain combinations. These can improve harvests, reduce disease and help with pest control by attracting helpful insects.

    For example, some kinds of soil bacteria take nitrogen from the air and make it into a form that plants can use. The plants hold the nitrogen in their roots. Legumes (豆科植物) are especially good at this nitrogen (氮) fixing. Then any crops that share the same space with the legumes can get the nitrogen when the roots are broken down.

    Beans and potatoes can also share territory well because their roots reach different levels in the soil. Deep-rooted vegetables get nutrients and moisture from lower down in the soil, so they do not complete with plants with shallower roots.

    But some plants placed together may harm each other's development. For example, tomatoes do not like wet soil but watercress does, so you would probably want to keep them separated.

    Some kinds of produce should be kept apart even after being harvested. This is because of ethylene gas (乙烯气体). Ethylene is a plant hormone (激素) that can cause some foods to ripen too quickly. Apples release ethylene gas. Apricots, melons and tomatoes also release a lot of ethylene. Some vegetables are easily affected by ethylene, including asparagus, broccoli, cabbage and cucumbers.

    This risk of ripening too soon is why markets often separate high ethylene-producing foods from those that are sensitive to the gas. But if you put an apple in a bag with a green banana, the ethylene from the apple will make the banana ready to eat sooner.

    What about peaches, plums and nectarines? These kinds of fruit do not need any help from an apple—they release enough ethylene to ripen themselves. But that does not mean there is no way to get the job done faster.

    Growers suggest placing the fruit in a fruit bowl or in a paper bag with the top folded over. Keep the fruit at room temperature, out of direct sunlight. Once the fruit is soft enough, either use it or put it in the refrigerator to keep it from getting too ripe.

    A study found wireless signals are able to pass through bags and suitcases to judge the sizes of dangerous metal objects and identify them." These items could include weapons, chemicals, laptops and batteries for bombs, "the research team said on Tuesday.

    Research suggested that Wi-Fi can now be used to estimate the volume of liquids such as water, acid, alcohol and other chemicals for explosive material. The study led by researchers at the Wireless Information Network Laboratory (WINLAB) in the School. of Engineering showed a wireless device with two to three antennas(天线)that could be fitted in existing Wi-Fi networks.

    The detection system analyzes what happens when wireless signals go through and bounce off objects or materials. The approach, which the paper states, works by separating the wireless interference(干扰)caused by two factors of objects-the material and shape." Most dangerous objects such as weapons are usually metal or liquid, which have significant interference," researchers said.

    When it was tested on a backpack, the accuracy rate topped 95 percent. "But the accuracy dropped to about 90 percent when objects inside bags are wrapped. And the tech could save lives if used in museums, stadiums, theme parks or schools," the team said, noting its design can inspect bags or luggage without being an exposure to privacy.

    It uses channel state information (CSI) that is readily available in low-cost Wi-Fi devices." This could have a great impact on protecting the public from dangerous objects," said Yingying Chen, a co-author of the study," There's a growing need for that now. In large public areas, it's hard to set up expensive screening equipment like what's in airports. Manpower is always needed to check bags and we want to develop a method to try to reduce manpower.”

    The peer-reviewed study, which recently won a best paper award at the 2018 IEEE Conference on Communications and Network Security, is now published online." Future work will continue to focus on ameliorating the accuracy of identifying objects and imaging shapes and volumes," researchers said.

    We all are familiar with Android and iOS platforms as both are popular but are quite different when it comes to functionalities.

    If you are making a big move from Android to iPhone, then the first thing that counters your mind is how to get your data on the iPhone.

    Note: You need to turn on Wi-Fi on your Android & iPhone and connect them with the same network.

    So, let's get started and learn how to transfer data from Android to iPhone.

    Note: Please keep in mind that the steps might vary from device to device.

    Install (安装) the "Move to iOS" App on your Android device from the Google play store. This application is developed by Apple and available for free.

    Once you are done with installing the app, you need to grant permissions to the app. Now, follow on-screen instructions to proceed.

    Now, keep your Android aside and start your iPhone. Follow the on-screen instructions to set up your iPhone.

    The transfer might take a bit longer depending upon the size of the content.

    On your iPhone screen, you will see a screen saying," Continue setting up iPhone".

    You can continue setting up your Apple ID on your new iPhone. Once done, you will find all your data such as contacts, messages, bookmarks, pictures etc. on it.

    That's it, now you can dump your old Android phone and enjoy using your iPhone.

    A nation's humor is linked to the historical development of the country. How funny somebody finds a certain thing depends on many things including ages, personal experiences, levels of education and locations. Therefore, humor is something that is not always transferable (可转移的) in another country.

    What about when both countries speak the same mother tongue? Does that mean they will then share the same sense of humor, or can differences still take place? Let's take the example of Britain and America. Time and time again, people say that Brits and Americans don't "get" each other's sense of humor. It is often argued that one of the most common differences between the British and American sense of humor is that Americans don't understand irony (反话). Simon Pegg explores this topic in depth in his article What Are You Laughing At? He concludes that this statement isn't true and I agree with him.

    In fact, Brits use irony on a daily basis while Americans don't. I think Americans understand British irony (most of the time anyway); what they don't understand is the need to use it so frequently. When Americans use irony, they tend to say that they are "only kidding". They feel the need to make a joke more obvious than Brits do. Maybe this comes from a fear of offending (冒犯) people.

    The American sense of humor is generally more slapstick (闹剧的) than that in Britain. I think this arises from a cultural difference between the two. Their jokes are more obvious and forward, a bit like Americans themselves. British jokes, on the other hand, tend to be more subtle. This may stem from the fact that British culture is more reserved (矜持的) than American culture.