The plants grown by Wageningen University researchers in Mars-like soil back in March have been analyzed and the results are excellent: at least four of the crops do not contain harmful heavy metal levels and are perfectly safe to eat, the University researchers report.

    If you've seen The Martian, you can remember how much Matt Damon got done living off of his poo-powered crop of potatoes. It just goes to show how important it is for a long-term colony to be able to grow their own food locally. We've taken one step closer to that goal in March, when Netherlands' Wageningen University reported that they've managed to grow ten different crops in Mars-like soil.

    However, growing food doesn't do us much good if eating it kills us, and researchers were worried that these crops contained dangerous heavy metals like lead or cadmium(镉) from the martian soil. But future colonists are delighted, as lab analysis of the crops determined that at least four of them are safe to eat.

    Led by ecologist Wieger Wamelink, the team tested radishes, tomatoes, rye, and peas. They looked at cadmium, lead, aluminium(铝), nickel(镍), copper, chrome(铬), iron, arsenic(砷), manganese(锰), and zinc(锌) contents in the plants, and didn't find any in dangerous levels. In fact, some of these vegetables have lower levels of heavy metals than those grown in regular potting soil. The plants were also tested for vitamins, alkaloids(生物碱), and flavonoids(类黄酮), with good results. While there are six more crops to test, Wamelink himself said that the results up to now are “very promising.”

    “Growing food locally is especially important to our mission of permanent settlement, as we have to ensure sustainable food production on Mars. The results of Dr. Wamelink and his team at Wageningen University & Research are significant progress towards that goal,” said Mars One co-founder and CEO Bas Lansdorp in a press release.

    A crowdfunding campaign is underway (and will be until the end of August) to fund the test of the remaining crops, potatoes included. If all the crops test out safe, with concentrations of heavy metal the FDA and the Dutch Food Agency consider as safe, Wamelink's team will host a “Martian dinner” at the Wageningen greenhouse. But I've seen the movie. Stay clear of the potatoes.

    Don't you just love ice skating every winter?I am sure that since winter is approaching,your skates are set to come out,just waiting to be used.Impress your friends with your new trick on how to ice-skate backwards with the help of these tips.

Stand Straight

    The first thing that you need to do is,stand straight.If you feel that you are falling backwards,just put your chin up and slightly bend your knees.

Confidence is What You Need

    The most important step while learning how to skate backwards,is having enough confidence in what you are doing.How can you achieve this?By practice.Just practice rolling backwards down a gentle slope everyday or just by pushing off from a wall or something of that sort.But before you do that,make sure that the place where you are practicing is free from any kind of debris（碎片）because otherwise,you could land up in the hospital due to some accident.While going backwards,just get used to the feeling of moving backwards.One of the important ice skating tips and techniques is that if you feel that you are losing your balance,then scissor（做剪式运动）your skates.Keep practicing this till you are confident about it.

Maintain Speed

    Confident now?Great!Now the next step is to maintain your speed.While rolling in a straight line with one skate, with the other try sculling（划桨）,that is,keep pushing yourself backwards with an outwards stroke（滑动）.Make sure that you put most of your weight on the skate which is moving straight and not the one with which you are sculling.Now,try the same thing using the other foot.Again keep doing this till you are confident enough.

Increase Your Speed Now

    Once you are confident that you can scull with either foot,the next thing that you have to do is increase your speed.Try some of your own tricks now.Scull with either foot or with both at the same time. 

Scull and Be Aware

    While you keep one foot straight,keep sculling with the other.You can do that with both feet at the same time. Concentrate on what you are doing but don't get so absorbed,that you don't see where you are going.If you are not watching your back,you might bang（碰撞）against something or someone.

    A new generation addiction(上瘾) is quickly spreading all over the world. Weboholism（网瘾）, a twentieth century disease, affects people from different ages. They surf the net, use e-mail and speak in chat rooms. They spend many hours on the computer, and it becomes a compulsive habit. They cannot stop, and it affects their lives.

    Ten years ago, no one thought that using computers could become compulsive behavior that could affect the social and physical life of computer users. Such behavior has seriously affected teenagers and college students. They are likely to log(写日志) on computers and spend long hours at different websites.

    They become hooked(着迷) on computers and gradually their social and school life is affected by this situation. They spend all free time surfing and don't concentrate on homework, so this addiction influences their grades and success at school. Because they can find everything on the websites, they hang out there. Moreover, this addiction to websites influences their social life.

    They spend more time in front of computers than with their friends. The relation with their friends changes. The virtual life becomes more important than their real life. They have a new language that they speak in the chat rooms and it causes cultural changes in society.

    Because of the change in their behavior, they begin to isolate themselves from society and live with their virtual(虚拟的) friends. They share their emotions and feelings with friends who they have never met in their life. Although they feel confident on the computer, they are not confident with real life friends they have known all their life. It is a problem for the future. This addictive behavior is beginning to affect all the world.

    It's generally believed that people act the way they do because of their personalities and attitudes. They recycle their garbage because they care about the environment. They pay $5 for a caramel brulee latte because they like expensive coffee drinks.

    It's undeniable that behavior comes from our inner dispositions（性情）,but in many instances we also draw inferences about who we are,as suggested by the social psychologist Daryl Bern,by observing our own behavior.We can be strangers to ourselves.If we knew our own minds,why would we need to guess what our preferences are from our behavior?If our minds were an open book,we would know exactly how much we care about the environment or like lattes.Actually,we often need to look to our behavior to figure out who we are.

    Moreover,we don't just use our behavior to learn about our particular types of character—we infer characters that weren't there before.Our behavior is often shaped by little pressures around us,which we fail to recognize.Maybe we recycle because our wives and neighbors would disapprove if we didn't.Maybe we buy lattes in order to impress the people around us.We should not mistakenly believe that we always behave as a result of some inner disposition.

    Whatever pressures there can be or inferences one can make,people become what they do,though it may not be in compliance（符合）with their true desires.Therefore,we should all bear in mind Kurt Vonnegut's advice:"We are what we pretend to be,so we must be careful about what we pretend to be."

    We all have different ways to navigate (导航) when lost—whether asking a stranger for help, consulting an old-school map or simply following our nose. But on a bike, the risks are higher. One wrong turn or that you're in a traffic jam with two lanes between your bike and the nearest pavement may ruin your good mood. Although cyclists, of course, managed to navigate before smart phones, cyclists can make two choices: a few stay calm and embrace getting lost, and the rest turn to a navigation app.

    Google Maps added a directions function for cyclists in 2015 in the US and Canada, and two years later across Europe. And while there are dozens of other apps now offering a similar service, Google Maps has the demerits for many, so the app seems to be falling behind expectations.

    As someone with no sense of direction, I knew it wouldn't be easy when I started cycling earlier this year. I appreciated that the app gave me two warnings before I needed to turn off a road, and automatically recalculated my route if I accidentally went off course. But still, it wasn't a smooth process. Google Maps thought I could cut across a double carriageway with no breaks in its barrier, assumed I knew what it meant when it told me to “head west”, and thought nothing of taking me the wrong way down a busy one-way street.

    Cyclists don't just want safety—they want convenience. Londoner Robson Smith regularly cycles between Clap ham and the City of London and would like to see Google Maps calculate routes where his bike is allowed on public transport and more choice of the type of routes he can take. “Google tends to calculate the most common and comfortable cycle routes. It would be better to have an option which included the fastest route, regardless of comfort,” he says.

    For this reason, Robson says he uses the app Cycle Streets instead. It offers a choice of four different route modes, based on the type the user wants, and saves previous routes. It also tells you how many calories a route burns, how many traffic lights you wilt encounter, and how busy it is.

    Winter is for working hard, summer is for playing hard. From the Bahamas to Amsterdam, we have several most appealing summer vacation spots for you to choose from.

    The Bahamas

    While there is a risk of getting rained on during hurricane season, June generally sees mild weather, fewer crowds and significantly lower prices. While some resorts (度假胜地) in the Out Islands may close, New Providence and Paradise Island remain open year-round. It's a good choice for families looking for a taste of relaxing island living.

    Mackinac Island, MI

    Mackinac Island, 20 minutes by boat from either the Upper or Lower Peninsula of Michigan, comes alive on summer weekends. Most of its roughly 4 square miles is parkland, suitable for hiking and cycling. Be sure to take in the beautiful architecture―Victorian cottages that date back to just after the Civil War. You can have a taste of times gone by; cars were banned more than a hundred years ago, and horse-drawn carriages are still used to get around today.

    Ocean City, MD

    This East Coast beach town is best known for its boardwalk, which is known for old-school amusement rides. Cycling in the town is also a great pleasure. Grab your wallets and feast on hard-shelled crabs at Hooper's crab house or drink in the sunset with a local beer in hand from Fager's Island Restaurant & Bar's large bayfront decks. Parking is free with your consuming receipt. You can't miss a classic walk along the boardwalk and the taste of Thrasher's vinegar and Old Bay French fries.

    Amsterdam

    Summer is the ideal time to visit this city. The gray skies have lifted, festivals abound and events to enjoy include the Open Garden Days, when visitors can peek (窥视) into the private gardens behind the beautiful Houses that line the famous canals. You can experience urban adventure, crossing Amsterdam's thousands of bridges and waterways by bike and by boat in search of the perfect brown cafe.