“A photograph that one has taken of oneself, typically with asmart phone or webcam and uploaded to a social media website” is the definitionof “selfie” in the Oxford English Dictionary. In fact, it wasn't even in thedictionary until August of last year. It earned its place there because peopleare now so obsessed with (对……痴迷) selfies ─ wetake them when we try on a new hat, play with our pets or when we meet a friendwhom we haven't seen in a while.

But is there any scientific explanation for this obsession?Well, you should probably ask James Kilner, a neuroscientist(神经系统科学家) atUniversity College London.

Through our lifetime we become experts at recognizing andinterpreting other people's faces and facial expressions. In contrast,according to Kilner, we have a very poor understanding of our own faces sincewe have little experience of looking at them ─ we just feel them most of thetime.

This has been proved in previous studies, according to the BBC.

Kilner found that most people chose the more attractive picture.This suggests that we tend to think of ourselves as better-looking than weactually are. To further test how we actually perceive our own faces,Kilner carried out another study. He showed people different versions of theirown portrait ─ the original, one that had been edited to look less attractiveand one that was made more attractive ─ and asked them to pick the versionwhich they thought looked most like them. They chose the more attractiveversion.

But what does it say about selfies? Well, isn't that obvious?Selfies give us the power to create a photograph ─ by taking it from variousangles, with different poses, using filters (滤色镜) and so on ─that better matches our expectations with our actual faces.

“You suddenly have control in a way that you don't have innon-virtual(非虚拟的)interactions," Kilner told the Canada-based CTV News. Selfies allow you“to keep taking pictures until you manage to take one you're happy with”, heexplained.

    She was walking home from work one evening when she got the idea. Rosa didn't like her job at the factory, but it was better than no job at all. So, while she was trying not to think about work, she saw the pots in an alley. They were cheap plastic pots, but there were dozens of them piled up behind the flower shop. Such a waste, she thought. When the pots were still there three days later, Rosa went in and asked if she could take some. The flower shop lady said she didn't mind, so Rosa carried home a tower of pots, pretending she was a circus performer on the way.

    At home, Rosa set them on the fire escape outside her tiny apartment. And there they sat. Once a gust of wind sent them slipping to the street three floors below, and she had to go to run after and catch them before the gathering storm.

    Every day, Rosa went to work and thought about her pots- She was wailing for something, but she had patience.

    At last, the newspaper brought good news. A hardware store had a sale on potting soil. Rosa carefully counted her money, then walked six blocks to the store. She bought six bags and carried them home. She bought seeds, too. Rosa slept well that night and dreamed of masses of flowers and fat, glowing fruits,

    Sundays were always good days. Rosa didn't have to work on Sundays. But Rosa couldn't remember when she had had such a good Sunday. She got up early and ate her breakfast on the fire escape with her pots. Then, she began to put dirt into the pots. She sang a little song until all six of her bags of soil were empty. Then, she laid her precious seed packets out and planned her garden. Tomatoes for the biggest pots, and peppers for the next-biggest ones. Flowers in all the rest.

    At the end of the day, Rosa sat in her garden and watched the sunset. Soon, she thought, there will be masses of flowers and fat, glowing fruits.

    She sat at the picnic table alone. Recess(休息) was in full swing. She remained awkward around her classmates. She seemed unsure of what to do or say, yet I could see her eyes longing for acceptance. Many students had already decided that her friendship would not be worth the energy required to overcome the awkwardness. Others teased her. Most ignored her — except for one.

    Brianna, the class clown, was making the other students laugh, as usual. “Brianna, do you see Molly down there? Would you mind walking down there and inviting her to come up here with the rest of us?”

    Brianna sighed. I could tell she didn't want to sacrifice precious minutes of her own recess to do what I was asking of her, but I also knew her heart. She often thought of others before herself — a rare character for anyone, much less a kid.

    Knowing this choice was hard for her, I pulled out a D-buck, our class currency. Though bribery(行贿) was not the ideal way to handle this situation, I needed her cooperation.

    “Here, I'll pay you for your time.”

    She offered an insincere smile, grasped the green paper, and headed down the hill.

    As the rest of the children screamed and laughed, my eyes locked on Brianna as she neared the picnic table. Molly could be difficult, and I wouldn't have been surprised if she sent Brianna back alone, refusing her invitation. When she encouraged herself to a standing position, I sighed with relief.

    A minute later, 1 felt tap on my shoulder. “Here, Mrs. D.” She handed me the D-buck.

    “ Why?” I asked.

    “I shouldn't keep this.” Her eyes fell to her feet, guilt radiating from her quiet voice. “I don't want Molly to think 1 only went to get her so I could earn a muck. She's my friend.”

    A moment later, they were all laughing again, and who should I see among them, laughing for the first time that week? Molly.

    The latest IPCC report does not mince words(直言不讳地) about the state of our planet: we must act now to achieve global change at a scale that has “no documented historical precedent(先例)” in order to avoid the climate disaster that would result from a 2 degree C rise in average global temperature. Climate change already affects the world's most helpless people including poor rural communities that depend on the land for their livings and coastal communities. Indeed, we have already seen the clear asymmetry(不对称) of suffering resulting from extreme weather events, such as hurricanes, floods, droughts, wildfires and more.

    So far, advocates and politicians have tended to focus on reducing fossil fuel(矿物燃料) consumption through technology and/or policy, such as a sharp carbon tax, as climate solutions. These proposals are, of course, essential to reducing manmade carbon emissions(排放)-71 percent of which are produced by just 100 fossil fuel companies.

    Yet the international focus on fossil fuels has overshadowed(使......显得不重要) the most powerful and cost-efficient carbon-capture technology the world has yet seen: forests. Recent scientific research confirms that forests and other “natural climate solutions” are absolutely essential in reducing climate change. In fact, natural climate solutions can help us achieve 37 percent of our climate target, even though they currently receive only 2.5 percent of public climate financing.

    Forests' power to store carbon dioxide through the simple process of tree growth is staggering: one tree can even store an average of about 48 pounds of carbon dioxide in one year. Recent research show undamaged forests are capable of storing the same amount of the carbon dioxide emissions of entire countries such as Peru and Colombia.

    For this reason, policy makers and business leaders must create and strengthen ambitious policies to prevent deforestation, and support the sustainable management of standing forests in the fight against climate change. Protecting the world's forests ensures they can continue to provide essential functions aside from climate stability, including producing oxygen, filtering water and supporting biodiversity. Not only do all the world's people depend on forests to provide clean air, clean water，oxygen, and medicines, but 1.6 billion people rely on them directly for their livelihoods.

    On November 7, Lewis Pugh completed a one-kilometer swim in the freezing waters of King Edward Cove, off South Georgia in Antarctica. He was wearing only his swimming glasses, cap and speedos!

    Pugh is an advocate for our oceans and seas, working to protect these ecosystem with their large diversity of marine life. When asked why he doesn't wear a wetsuit, Lewis says, "I ask world leaders to do everything they can to protect our oceans. Sometimes the steps they need to take are difficult and unpopular. If I'm asking them to be courageous, I must also be. Swimming in a wetsuit would not send the right message."

    It took Pugh about 19 minutes to complete the one-kilometer swim in Antarctica where the water averaged about 1.6 degrees Celsius. He says that his body can only tolerate about 20 minutes in the freezing waters before it starts shutting down. As he swims, his body temperature steadily drops, which in turn causes his muscle control to drop, slowing him down. When he is done with his swim, his support team rushes him to a hot shower and it takes almost an hour for his body temperature to return to normal.

    Doctors and Pugh caution that one must receive months of training to swim in such cold waters. Even expert swimmers who are unused to freezing water can drown within minutes because of the physical shock experienced by the body. Pugh says he trained for six months before this swim.

    This is not the first time that Lewis has swum in dangerous conditions. In 2007, he swam one kilometer in the North Pole to draw attention to the melting Arctic ice due to climate change. In 2015, he swam in the Bay of Whales in Antarctica's Ross Sea as part of his successful campaign to help set up a marine reserve there.

    On Tuesday. Google announced a new feature (特点) for the Google Assistant. People can send reminders to friends and family on their phone or their Google Home equipment.

    Google has named the new feature Assignable Reminders. Here's how the new Assignable Reminders feature works with Google Assistant.

    You start off by simply starting the Google Assistant by saying "Hey Google" or by whatever shortcut (快捷键) you have set on your phone. After this, you can tell Google Assistant to remind someone of something at a certain time.

    This feature will also be feasible on the Google Home smart speaker, or a smart display which works with Google Assistant. The person receiving the reminder can also replay the reminder by asking Google Assistant to show them a list of all their reminders.

    These reminders can only be sent to people who are already listed as family in your Google account (账户) or people who are linked (连接) and voice-matched to the same Google Home equipment.

    Another feature built within Assignable Reminders is the ability to set reminders based on someone's place. For example, you can set a reminder for friends to buy you something from a store as soon as they reach there.

    Assignable Reminders will be put into use in the next few weeks in the U.S. , the U.K, and Australia.