Children in the United States eat too much pizza that some researchers now argue the food should join the ranks of sugary drinks and fast food for the harm they do to health．

    In a new study, the researchers found that pizza is a large source of calories, saturated fat(饱和脂肪)and salt in children's diets．Children should not eat more than two slices of pizza for a meal，and should pair that with salad, rather than with another high-calorie food，the researchers concluded．

    “Parents should aim to control pizza consumption(消费), particularly as a snack where it was shown to have a very adverse impact on children, and they should put their pizza dollars toward healthier brands．”Said Lisa Powel, director of the Illinois Prevention Research Center．

    Pizza has become a matter of focus in recent years for researchers who look at the meals children eat, rather than the nutrients within them．Studies have found pizza is among the greatest sources of calories for children．

    “Since pizza remains a common part of children's diet, we need to make 'healthy' pizza．”Powel said．To make pizza healthier, food producers should reduce its saturated fat and salt, and increase its whole grain content,” she said．

    Whether or not pizza is harmful enough to be picked out as an unhealthy food, the study attracts attention to a larger issue with the modern American lifestyle, said Alexis Tindall, who was not involved in the flow research. “Many foods are eaten too frequently and in large sizes,” said Tindall．To solve the problem, people don't have to give up eating pizza, but instead, they can eat smaller and healthier pizza，”she said．

    “Make it at home, instead of ordering it out where you don't have any control over how it's made.” Tindall said. “When we make it at home, we can choose healthier ingredients，increase the vegetables, reduce fat, and put in less cheese．Pizza doesn't have to be just pepperoni(意大利辣香肠)and cheese．”

    Spider monkeys have long, thin arms with hook like hands that allow them to swing through the trees. They do not have opposable thumbs(对生拇指).

    The brown-headed spider monkey has a prehensile(缠绕性的)tail, which means it can grasp and can be used like a fifth leg to grab trees. During the day, the spider monkey searches for fruits, which make up the main part of its diet. They will also eat flowers, seeds, leaves, and small insects during the dry season when fruits aren't available. They spend most of the daylight hours climbing and swinging through the high branches of trees.

    The brown-headed spider monkey lives in a large community of about 20 to 100 male and female monkeys. They split into smaller groups for feeding. Females usually give birth to only a single baby each year or two. Young monkeys are carried on their mothers' stomachs until about 16 weeks old. Then they are strong enough to ride on their mothers' backs. All brown-headed spider monkey babies are born with a pink face and ears.

    Spider monkeys hug each other and wrap their tails around each other. They are very intelligent and have strong memories. They were named spider monkeys because they look like spiders as they hang upside down from their tails with arms and legs swinging. Their genus (属)name is Ateles, which means “imperfect”. This refers to the fact that they don't have thumbs.

    Hunting the brown-headed spider monkey is now barred in Ecuador, a country in northwestern South America, but humans have killed them for their meat for hundreds of years.

    Whenever we see a button on a doorbell or on a remote, we may press it. This is true in most cases. But some buttons are actually fake(假的), like the "close" button on an elevator.

    Many people are in the habit of pressing the "close" button because they don't have the patience to wait for the elevator doors to shut. But according to experts, the buttons are a complete trick—the doors will not close any faster however hard you press.

    It started in the 1990s when the Americans with Disabilities Act was passed, making sure that all elevators stayed open long enough so that people with disabilities could enter. Only firefighters and maintenance workers(维修工) can use the buttons to speed up the door-closing process if they have a code or special keys. But to normal elevator riders, the buttons aren't completely useless.

    According to psychologists, fake buttons can actually make you feel better by offering you a sense of control. Experts have showed that a lot of buttons that don't do anything exist in our lives for this same purpose. For example, pedestrian crosswalk buttons don't live up to their names. Pressing them used to help make the traffic signals change faster, but that was before computer-controlled traffic signals were introduced.

    But psychologists found it interesting that even when people are aware of these little "white lies". They still continue to push fake buttons because as long as the doors eventually close, it is considered to be worth the effort.

    That habit is here to stay, John Kounios, a psychology professor at Drexel University in the US, told The New York Times. "After all, I've got nothing else to do while waiting. So why not try the chance?"

    Despite what so many people would love to believe, NASA hasn't discovered any evidence of past or present intelligent life on Mars. So, when the Curiosity rover (好奇号探测器）found something suspicious on the Red Planet's surface, they were not only surprised but also a little bit worried.

    The thin fragment (碎片）was suspicious enough to guarantee its own name, with NASA's Curiosity rover team calling it the “Pettegrove Point Foreign Object Debris,” named for the location where it was discovered. With no idea what it was or where it came from, the rover s handlers began to worry that it might actually be a piece of the rover itself, suggesting some unseen damage or other issue with the robot. Thankfully, those concerns seem to have been unfounded.

    In a new update from NASA the object has now been identified as a natural piece of rock rather than a piece of any man-made craft or vehicle. The team analyzed the bizarre object with a tool called the ChemCam RMI. The instrument uses a laser (激光器）t0 sniff out the makeup of anything it's pointed at, and the results for this particular piece of debris revealed that it's actually just a very thin piece of rock.

    NASA describes the inspection： The planning day began with an interesting result from the previous plan's ChemCam RMI analysis of a target that was referred to as “Pette Point Foreign Object Debris” （PPFOD),and speculated to be a piece of spacecraft debris fact was found to be a very thin flake of rock, so we can all rest easy tonight-Curi0sity n0t begun to shed its skin!

    How this particularly thin sliver of rock got to where it is—and why it seems to be a different colour than the surrounding sand and debris-remains unexplained, but at least the rover falling apart.

    Some people think going to the gym takes time and effort, it often hurts, and it can be extremely boring. Most weight-related exercises are a combination of sets and reps(几次几组). In order to see any significant change from any one exercise, it will probably need to be repeated six to eight times, for a minimum of three sets, for about three months: Then there's aerobics(有氧运动). For some, there's nothing more boring than endless miles spent running on a treadmill(跑步机).

    But what if there is a way to reduce the boredom of exercise while still getting a good workout? Luckily for us, there's virtual reality (VR).

"In the past, playing video games was a sedentary(久坐不动的) experience," says Jo Stauffer of the VR Heaitn-institute, but VR changes all of that. " Many VR games are played while standing In order to play properly, the players are forced to move around swinging their arms or using their legs. After an hour of this on a regular enough basis, it's not surprising, that many people unexpectedly find themselves a little fitter. There are already a number of virtual reality games which, deliberately or not, result in their player "getting a good sweat on" if played for enough time. For example, there's a music game which forces players to shadow box(做空拳攻防练习) in order to hit the notes—that's an upper-body workout.

    The benefit of VR has been noticed by one company. They want to take the whole experience into the gym. They are making a resistance machine, designed to be used in combination with a VR headset. Players challenge a virtual competitor in a series of games, which results in a 30-minute full-body workout. However, the cost of the equipment is expensive and there are safety concerns to be worked out, says J. P. Gownder from the consultancy Forrester.

    Although it's early days, for those: of us who struggle to overcome the boredom of exercise, a new solution could be coming. And a world where a person can exercise and have fun at the same time might be something that many people would want-virtual or not. So don't give up exercising.

The huge billboard at the side of the highway is no joke; transporting firewood in certain areas is a crime, punishable by a four-thousand-dollar fine. The reason? Emerald Ash Borer disease, or EAB disease, a new addition to the long list of dangerous foreign pest infestations（虫害）on American soil. It was in 2002 when the Emerald Ash Borer beetle（甲虫）was first discovered in Michigan. Not long after, the pest was found in Ohio. Originally from Asia, this green beetle probably found its way to North America through a wooden box made of ash wood and immediately settled into a local ash tree. In little time, the species managed to kill millions of ash trees. 

To date, much work is underway to stop ash trees ending up in the same group as elm and chestnut trees, which are all dying out in many areas. Ash Borer Infestations are particularly troublesome because they are difficult to identify until the ash tree is heavily infested. In addition, other ash trees in the area surrounding the source will probably also be infested, making control a hard task. 

Researchers are working on many issues related to the control and removal of this harmful beetle. For example, it has been discovered that Asian ash trees are not destroyed by this native borer. It may be that, Asian ash trees have developed genes（基因）to protect them from the insect; therein, perhaps, lies the secret to controlling this pest. Insecticide（杀虫剂）treatment is also being explored on several fronts. Research is underway to determine which insecticides are proving to be the most successful. The proper application of the insecticides is being debated. 

However, all possible solutions require a great deal of study and research. In the meantime, careful steps must be taken. Methodical identification of infested trees is taking place. Identified trees are being cut down and destroyed to get rid of the beetle colonies（群）. In the end, this puts a huge drain（消耗）on city budgets, as tree removal can be extremely expensive. 

Even though it will be expensive to deal with this problem in the short term, the costs of doing nothing could be far higher, since we could lose an entire species of tree.