Cold weather has a great effect on how our minds and our bodies work. Maybe that is why there are so many expressions that use the word cold. For centuries, the body's blood has been linked closely with the emotions. People who show no human emotions or feelings, for example, are said to be cold –blooded. Cold –blooded people act in merciless ways. They may do cruel things to others, and not by accident. For example, a newspaper says the police are searching for a cold-blooded killer. The killer murdered someone, not in self-defense. He seemed to kill with no emotion.

    Cold can affect other parts of the body, the feet, for example. Heavy socks can warm your feet, if your feet are really cold. But there is an expression—to get cold feet –that has nothing to do with cold or your feet. The expression means being afraid to do something you had decided to do. For example, you agree to be president of an organization. But then you learn that all the other officers have given up the position. All the work of the organization will be your responsibility. You are likely to get cold feet about being president when you understand the situation.

    Cold can also affect your shoulder. You give someone the cold shoulder when you refuse to speak to them. You treat them in a distant, cold way. The expression probably comes from the physical act of turning your back toward someone, instead of speaking to him face-to-face. You may give a cold shoulder to a friend who has not kept a promise he made to you. Or, to someone who has lied about you to others.

    A cold fish is not a fish. It is a person. But it is a person who is unfriendly, unemotional and shows no love or warmth. A cold fish does not offer much of himself to anyone.

    Out in the cold is an expression often heard. It means not getting something that everybody else got. A person might say that everybody but him got a pay raise. He was left out in the cold. And it is not a pleasant place to be.

    What is it?

    KindSpring has created a series of 21-Day Challenges designed to help individuals and groups grow in values that help create positive change. Regardless of profession, age, culture or geography, when we try to cultivate(培养) certain values we create a ripple effect(连锁反应) that has the power to transform our lives and the world for the better. When we practice these values together over and over again, our efforts encourage and strengthen each other in remarkable ways. Each of our 21-Day Challenges focuses on a specific value — from kindness to mindfulness. Click here for more information.

    How does it work?

    A small daily commitment + a daily prompt(提示)+ a process for communication. Each 21-Day Challenge invites participants to carry out one small daily action related to the main theme. Every day for three weeks a unique idea is emailed out that serves as a prompt. Participants are encouraged to carry out the act and share stories of their experiences in both online and offline spaces. You can sign up to participate as an individual or you can “host” a challenge for a group you belong to. The challenges were developed for workplace, school/college and family environments, but are broadly usable. Any group is more than welcome to take them on. At the end of 21 days, you may continue the practice with your group, take on a new challenge, or even design your own. There is no charge for any of our services. All the challenges are offered as a gift. Five steps to host a challenge.

    Why should we do it?

    The 21-Day Challenges are all designed to fit the pace of modern day life. They are not very time-consuming（耗时的）, and in most cases demand less than five minutes a day. Twenty-one days certainly can't change everything, but it can begin a new way of being. You are invited to bring these practices to your company, school, community center, or family. Get started with joining a challenge or hosting one here. Let us know if you have questions—we're delighted to help any way we can!

    Amazon.com has received a patent (专利) right to send its products to customers by drone planes. The company is the largest US-based online seller of products. It delivers those products to customers by mail and other services. Now, the company has received a patent for its planned drone delivery system.

    In March, federal officials allowed Amazon to test its drone delivery plan. But even with a patent and the ability of drones to make deliveries, it does not appear that the company will put its new delivery system in place any time soon.

    The US Patent Office published the document. It describes Amazon's plans to use GPS to deliver products to homes and to wherever people are. The drone will use a customer's mobile device—usually a smartphone—to avoid hitting people or buildings and to find a secure area to land. The company wants to deliver products within 30 minutes after people ordering them on its website.

    However, the Federal Aviation Administration (FAA) is worried about the safety. Although it allowed Amazon to test the system, the agency said the operators must be able to see the planes. That greatly limits (限制) the delivery area.

    Loretta Alkalay is a professor at the Vaughn College of Aeronautics and Technology in New York. Although Amazon is not yet offering drone delivery, Professor Alkalay says it will not be long before it does. She says there are worries that the drones will hit buildings or people, or that the products and drones will be stolen or damaged by people on purpose. But she says that is because many people believe the drones would only deliver the products to the front door of a house. "However, it is possible that homes will one day have special areas on their roofs designed to receive product deliveries," she adds.

    The New York See It All Tour is exactly what it sounds like: an all-inclusive guided tour of New York City.

    Central Park

    One of the most famous parks in the world, Central Park is a man-made wonder. Not only is it the first public park built in America, but it is also one of the most frequently visited parks, with over 25 million guests per year. Set in the middle of busy Manhattan, its grounds serve as a safe harbor, not only for athletes, and musicians but also for lots of migratory birds each year. One can spend an entire peaceful day wandering its grounds, gazing upon nearly 50 fountains, monuments, and sculptures or admiring its 36 bridges.

    Hudson River Park

    Hudson River Park is a waterside park on the Hudson River that extends from 59th Street south to Battery Park in the New York City district of Manhattan. Bicycle and pedestrian paths, including the Manhattan Waterfront Greenway, span the park north to south, opening up the waterfront for the public to relax. The park includes tennis and soccer fields, children's playground, dog run, and many other features.

    Washington Square Park

    Washington Square Park, located in the heart of Greenwich Village, is a very popular and often crowded square. People from all backgrounds gather to this large square dotted with trees.

    Central Park Zoo

    The Central Park Zoo is a small 6.5-acre zoo located on Central Park in New York City. The zoo began in the 1860s, making it the first official zoo to open in New York. The zoo was improved in 1934, with the addition of many new buildings ranged in a quadrangle around the sea lion pool. Finally, the zoo was repaired in the mid-1980s and reopened in 1988, replacing the old-fashioned cages with naturalistic environments.

    University of Pennsylvania researchers say that for the first time they have linked social media use to increases in depression and loneliness. The idea that social media is anything but social when it comes to mental health has been talked about for years, but not many studies have managed to actually link the two. To do that, Penn researchers, led by psychologist Melissa Hunt, designed a study that focused on WeChat, Snapchat and Instagram.

    The study was conducted with 143 participants, who before they began, completed a mood survey and sent along photos of their battery screens, showing how often they were using their phones to access social media. "we set out to do a study which attempts to imitate real life." Hunt said.

    The study divided the participants into two groups: The first group was allowed to maintain their normal social media habits. The other, the control group, was restricted to 10 minutes per day on social media. The restrictions were put in place for three weeks and then tested for now comes such as fear of missing out, anxiety, depression and loneliness.

    The results showed a very clear link between social media use and increased levels of depression and loneliness." Using less social media then you normally do would lead to significant decreases in both depression and loneliness " Hunt said.

    Social media invites what Hunt calls "downward social comparison." "When you're online, it can sometimes seem that everyone else is cooler and having more fun and included in more things and you're left out," Hunt said. And that's just generally discouraging. "Every minute you spend online is a minute you are not doing your work or not meeting a friend for dinner or having a deep conversation with your roommate." And these real life activities are the ones that you can encourage self-esteem and self-worth, Hunt added.

    "People are on their devices, and that's not going to change," she said. But as in life, a bit of control goes a long way.

Scientists have discovered a bit of hand-made string (线绳) that's around 50,000 years old in Neanderthal remains. The first Neanderthal remains were found in the Neander Valley in Germany, which is where the name comes from. Neanderthals may have lived mainly in caves and made stone tools, but recent discoveries have given hints that Neanderthals developed some advanced skills that people used to think impossible. For example, Neanderthals knew how to make glue from the bark (树皮) of a tree.

Now, scientists report they've found a piece of string on a stone tool made by Neanderthals. Before this, the oldest known piece of string was one made by humans about 19,000 years ago. The string is about a quarter of an inch long. Almost all things made from plants during that time have broken down and disappeared, so it's very special to find this bit of string.

The scientists don't know whether the string was attached to the tool. But that doesn't interest them as much as the fact that Neanderthals knew how to make string. Bruce Hardy, the lead scientist on the project, says that knowing how to make string was meaningful for humans. "We wouldn't really be here today without that technology," he says.

Making string is a very arduous process. This string was made from the inside bark of an evergreen tree. To make string that is strong enough, the string must be made of several smaller fibers twisted (缠绕) together in a special way. For the Neanderthal string, several fibers needed to be twisted together into something like yarn. Then three pieces of yam needed to be twisted together in the opposite direction to make the final string.

The scientists aren't sure what the string was used for, but they say that string like. the bit that was found could be used to make bags, baskets, traps, or other things. The researchers also suggest that because Neanderthals needed to make pairs and count fibers to make the string, the bit of string may also tell us something about the kinds of math that Neanderthals could do.