If you thought pilots dimmed（调暗）the lights before takeoff to give you some shuteye, think again. Believe it or not, the dim lighting could actually help save your life in case of a plane emergency.

    The dimmed lights before taking off the runway and landing are a flight precaution used to help passengers' eyes adjust quicker during an emergency escape. “Going from a brightly lit environment to one that's completely dark would require some time for our eyes to focus and see the escape slide,” Alice Theriault, service director for Air Canada wrote in a press statement. “Since we need to have all the seconds on our side in the event of an emergency, dimming the lights is one of many steps we take to ensure the safety of our customers.”

    The phenomenon that your eyes see those strange speckles (小斑点) as your sight adjusts to a dark place after being in a light place is called dark adaptation. It normally takes our eyes about 20 to 30 seconds to see best in a dark room. The brighter the lights, the longer it takes for our eyes to adjust, which is why dimming the plane lights could shorten your “dark adaptation” time since you haven't been sitting under fluorescent bulbs (荧光灯) all flight.

    Not only does dimming lights add valuable time to the escape process, but it reduces the tension on your eyes if you need to look outside, or see the emergency lighting along the passage. “It helps keep you in the right direction.” Patrick Smith, an airline pilot and author of Cockpit Confidential told The Telegraph. “It also makes it easier for flight attendants to assess any outside risks, such as fire or debris, that might affect an escape.” So next time a pilot dims the lights, just know it's for your safety, even though it creates a gentle atmosphere for your takeoff into the sky.

    A new high tech mirror, designed specifically for cancer patients, will only become reflective when a user smiles into it. The plug-in device, which exactly looks like a tablet, comes equipped with a mirror, a built-in camera, and a smart material triggered(触发)by some software. Facial recognition technology captures the face and instructs the surface of the mirror to change when a smile is detected. It can hang on a wall or sit on a table, much like a conventional mirror. Unlike a regular mirror, however, the price is currently standing at a surprising $2000—$3000.

    After witnessing a close family member struggle through cancer treatments, Turkish industrial designer Berk Ilhan decided to focus his work primarily on products that would cultivate joy and benefit cancer patients directly.

    “She told me in the first days after her diagnosis, it was difficult for her to look in the mirror and acknowledge she had cancer.” he said.“ Our facial expressions affect how we feel. If we flex(绷紧)our facial muscles to smile, our brains think that something good happened and as a result, we feel happiness.”

    After earning his master's degree at the School of Visual Arts in New York, Ilhan spent several weeks visiting cancer hospitals in Turkey, speaking to both patients and doctors. He spent two years designing and developing the mirror. The idea behind it is that smiling, even when forced, can make us feel better, according to research known as the facial feedback hypothesis. Laughter is linked to improved immune system function, and some researchers claim it can even increase our lifespans.

Ilhan is currently producing the mirror in limited quantities at the previously mentioned price. The product, however, will soon be launching a campaign in which Ilhan hopes to raise enough funds to bring the price down to $500.He also intends to donate the mirror to hospitals when it is financially possible to do so.

    Marathon fever is sweeping this country. In recent years, China's ever-growing passion for marathons has been triggered by its economic development and health-conscious middle class. A large number of marathon runners are white-collar workers, civil servants and business people that are keen on leading a healthy lifestyle. Government support, social participation and strong marketing by the sports industry have gradually led to the rapid development of the marathon industry, which is currently valued at 70 billion yuan ($10. 77 billion). Due to its large participation and nationwide media report, marathons are considered by local governments an important part of marketing their cities. Thus, many cities list unique routes across local scenic spots and historical attractions, not only to boost people's fitness, but also to promote local tourism.

    For many runners, marathons are a way of life." As we get older, the places and opportunities to meet new people decrease. I find that participating in marathons is a simple way to make friends," said Wu, who made many friends in the Xstop Running Community, a running club with 48, 000 members established by Xtep, one of the leading distributors of sports merchandise in China.

    "The sense of belonging and the mutual encouragement that exists within the running community are very attractive to many people. We easily befriend one another, since we have the same goal: to keep running and never stop," Wu said. Besides, a marathon can be a great way to explore new places. For a runner who also loves traveling, marathons are a solid choice. "Competing in an international marathon is a chance to experience a city or a country you've never visited before," said Meng, an experienced runner from north China's Tianjin Municipality, who often runs in London, New York and Melbourne.

    There's a unique perspective that people get running through the streets of a city, distinct ancient buildings or amazing natural settings, he explained, things that somehow just can't be seen by rushing in a car. In addition, during a race, streets are often closed off so you don't have to battle traffic.

Washington, D.C. Bicycle Tours

    Cherry Blossom Bike Tour in Washington, D.C.

    Duration: 3 hours

    This small group bike tour is a fantastic way to see the world-famous cherry trees with beautiful flowers of Washington, D.C. Your guide will provide a history lesson about the trees and the famous monuments where they blossom. Reserve your spot before availability—and the cherry blossoms—disappear!

    Washington Capital Monuments Bicycle Tour

    Duration: 3 hours (4 miles)

    Join a guided bike tour and view some of the most popular monuments in Washington, D.C. Explore the monuments and memorials on the National Mall as your guide shares unique facts and history at each stop. Guided tour includes bike, helmet, cookies and bottled water.

    Capital City Bike Tour in Washington, D.C.

    Duration: 3 hours

    Morning or Afternoon, this bike tour is the perfect tour for D.C. newcomers and locals looking to experience Washington, D.C. in a healthy way with minimum effort. Knowledgeable guides will entertain you with the most interesting stories about Presidents, Congress, memorials, and parks. Comfortable bikes and a smooth tour route (路线) make cycling between the sites fun and relaxing.

    Washington Capital Sites at Night Bicycle Tour

    Duration: 3 hours (7 miles)

    Join a small group bike tour for an evening of exploration in the heart of Washington, D.C. Get up close to the monuments and memorials as you bike the sites of Capitol Hill and the National Mall. Frequent stops are made for photo taking as your guide offers unique facts and history. Tour includes bike, helmet, and bottled water. All riders are equipped with reflective vests and safety lights.

A school district in Michigan has banned all backpacks from school buildings, in response to growing safety concerns. 

Flint Community Schools announced last week that backpacks would be banned and the ban would be in place for the rest of the school year. The new policy went into effect on Monday. 

"We are doing all that we can to create a safe and secure environment for our scholars, families, teachers and staff," Superintendent (主管) Kevin Jones wrote in a letter posted on the school district's website. 

Jones cited growing threatening behavior happenings across the country, including weapons being brought to schools, as the reason for the backpack ban. 

"Backpacks make it easier for students to hide weapons, which can be taken apart and harder to identify than hidden in pockets, inside books, or under other items," he said. 

Following the shooting at Robb Elementary School in Uvalde, Texas, last May, where 19 students and two teachers died, schools began taking policies requiring students to use clear backpacks. However, Flint Community Schools have gone a step further and banned clear backpacks from school buildings, with the superintendent saying that it doesn't resolve the issue. 

"By banning backpacks altogether and adding an increased security presence across the district, we can better control what is being brought into our buildings," Jones said. 

Students are allowed to store personal items like wallets, keys, hygiene products (卫生用品) and phones in small purses, bring lunchboxes or place their gym clothes in clear plastic bags, all of which will be subject to searches. 

If a student brings a backpack to school, parents or guardians must pick it up from the school, according to Jones. 

The Flint Board of Education, the district's administration and headmasters approved the policy change, Jones said, adding that the district received support from the Flint Police Department. 

If you've ever seen a sparrow steal your dog food or a crow open a garbage bag, you get a sense of that some birds have learned to take advantage of new feeding opportunities—a clear sign of their intelligence. Scientists have long wondered why certain species of birds are more innovative than others, and whether these capacities stem from larger brains or from a greater number of neurons（神经元）in specific areas of the brain.

It turns out that it's a bit of both, according to a recent study by an international team that included members from McGill University published in Nature Ecology and Evolution.

The researchers used a new technique to estimate the number of neurons in a specific part of the brain called the pallium in 111 bird species. The pallium in birds is equal to the human cerebral cortex（大脑皮层）, which is involved in memory, learning, reasoning, and problem-solving, among other things. When these estimates about neuron numbers in the pallium were combined with information about over 4,000 feeding innovations, the team found that the species with the higher numbers of neurons in the pallium were also likely to be the most innovative.

"The amount of time chicks spend in the nest as their brains develop might also play a crucial role in the evolution of intelligence," says McGill University Emeritus Professor Louis Lefebvre who spent more than 20 years gathering examples of feeding innovations. "Larger species of crows and parrots, which are known for their intelligence, spend longer in the nest, which allows more time for the brain to grow and accumulate pallial neurons."

The results of the study help to deal with previously opposed views of the evolution and significance of brain size and show how a life-history perspective helps to understand the evolution of cognition.