1 . By now, we are all aware that social media has had a tremendous influence on our culture, in business, on the world-at-large. Social media websites revolutionized the way people communicate and socialize on the Web. However, aside from seeing your friend’s new baby on Facebook, or reading about Justin Bieber’s latest conflict with the law on Twitter, what are some of the real influences?

Social networks offer the opportunity for people to re-connect with their old friends and acquaintances, make new friends, share ideas and pictures, and many other activities. Users can keep pace with the latest global and local developments, and participate in campaigns and activities of their choices. Professionals use social media sites like LinkedIn to enhance their career and business development. Students can work together with their peers to improve their academic and communication skills.

Unfortunately, there are a few downsides too to social networking. If you are not careful, immoral people can target you for cyber bullying and disturbance on social sites. School children, young girls, and women can fall victim to online attacks which can create tension and suffering. If you are a victim of cyber bullying, do not take it lying down, but try to take appropriate legal action against the attacker.

Many companies have blocked social networks as addicted employees can distract themselves on such sites, instead of focusing on work. In fact, studies show that British companies have lost billions of dollars per year in productivity because of social media addiction among employees.

Also, what you carelessly post on the Internet can come back to trouble you. Revealing (泄露) personal information on social sites can make users vulnerable (易受伤害的) to crimes like identity theft, stalking, etc. Many companies perform a background check on the Internet before hiring an employee. If a potential employee has posted something embarrassing on social media, it can greatly affect their chances of getting the job. The same holds true for our relationships too, as our loved ones and friends may get to know if we post something undesirable on social networks.

Social media has its advantages and drawbacks as each coin has two sides. It is up to each user to use social sites wisely to enhance their professional and social life, and exercise caution to ensure they do not fall victim to online dangers.

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2 . Vijay Gupta is known to classical music lovers across the United States. He serves as the first violinist for the Los Angeles Philharmonic. In that job, he often plays to large crowds, including many very rich people. When he is not performing, he organizes concerts for homeless people. “They have reminded me why I became a musician.” He said.

Last week, Gupta was recognized for being a founder and the artistic director of Street Symphony. The group has performed at homeless shelters, jails and halfway houses for about eight years. Gupta is among the 25 winners of the 2018 MacArthur Fellowship, commonly known as the “Genius Grant”. Each winner will receive $ 625,000 over five years to use as they wish. The money is coming from a private group, the John D. and Catherine T. MacArthur Foundation. It awards grants (补助金) to people whose work it considers exceptional and whose work “inspires hope in us all”. Gupta said he got the idea for Street Symphony while teaching Nathaniel Ayers, a trained musician whose mental illness led to his homelessness.

The 31-year-old winner said he did not know yet how he would spend the money. He has been a performer since the age of seven and the award will give him “space to breathe, plan and look ahead”.

Another winner is Rebecca Sandefur, an associate professor (副教授) of sociology and law in the University of Illinois. The Associated Press says her research actively supports new ways to involve poor communities in the U. S. justice system.

47-year-old Sandefur created the first national mapping of civil legal aid providers. It shows which states have the financial(金融的)resources to provide such aid and which don’t. She also found that the cost of legal services was only one of the things preventing poor people from getting lawyers. Among the others were fears of unfairness(不公平)in the legal system. Sandefur noted that a lot of attention had been paid to problems with the criminal justice system, but more attention must be paid to the civil side of the law, which also affected millions of people.

3 . To look inside an ant nest is to meet with an alien civilization. The boiling mass of worker ants beneath an upturned stone is both strangely reminiscent of (联想到) human society and strikingly different. There is an organization that fascinates us and a long line of myrmecophiles (or ant lovers) leads back all the way to King Solomon, who in fact advised people to “go to the ant, consider her ways and be wise”. This was exactly the inspiration behind Planet Ant, a TV program showcasing what we know about the kingdom of ants, and what ants can teach us about the human world.

Like us, ants build structures, find food, defend their societies and manage waste, and-also like us-they must be well organized. For example, the leaf-cutting ants of Planet Ant have special waste disposal areas for storing harmful waste and a team of “waste-disposal ants” dedicated to keeping the nest clean. But ants achieve this familiar final result in a very different way to humans. Human societies have centralized control. In other words, someone tells us what to do. Ants, on the other hand, have decentralized control and neither the queen nor any other ant directs work. Ant workers are the final self-starters, following specific, but potentially flexible, rules in certain situations.

Chemical trails underpin much of this self-organization. Foragers (觅食者) lay a mix of chemicals known as trail pheromone (信息素) behind them as they walk. Other ants follow the trail and if they find food they reinforce it, laying more pheromone as they return to the nest. Stronger trails are more likely to be followed, so trails leading to food become progressively reinforced, while trails with no food at the end fade away.

This combination of positive feedback and evaporation (蒸发) produces an effective foraging system that is very good at finding the quickest routes to food. This simple guiding principle, and others like it, have provided some useful solutions to the complex problems faced by engineers, computer scientists and businesses.

The other day, I went home so lately that my mother couldn't afford to wait me any longer. So she began to have a lunch by herself. When I opened the door, my mother seemed to feel a little embarrassing. She hurried to heat the dishes what had already turned a little cold on the table. I stopped her and saying with a smile, “It was not necessary, Mom. I can eat them.” I clearly remembered that my mother had taught me not to cause any trouble to other at any time. In fact, I just didn't want to trouble him any more as she was already too tired from doing the houseworks.

9 . Facial recognition technology has been already widely used by governments and some advertising companies. The technology uses machine learning tools to search for faces in an attempt to identify people.

In a recent study, scientists announced they had developed machine learning tools to track the faces of individual wild chimpanzees (黑猩猩). Dan Schofield said that the system was developed to improve the quality of information collected about chimpanzees in the wild over a long period of time.

"For species like chimpanzees, which have complex social lives and live for many years, getting a snapshot of their behavior from short-term field research can tell us only so much," Schofield said.

The researchers wanted to get a more complete understanding of the lives of the chimpanzees by studying them over several generations. But doing this would have required searching through hundreds of hours of video recordings of chimpanzees in the wild.

The researchers recorded the activities of a group of chimpanzees that lived in the West African nation of Guinea. A facial recognition computer model was trained with more than 10 million images of the animals. The model was then used to search for, recognize and track individual chimpanzees. The system was able to identify individual chimpanzees correctly about 92 percent of the time. It successfully identified the animals' sex 96 percent of the time.

The study included an experiment with humans to see how they could perform against the machine learning system in making identification. Humans were able to correctly identify individual chimpanzees about 42 percent of the time. The machine learning tool was much faster in completing the experiment. Human experts took about 55 minutes, while the computer took only several seconds.

The researchers say they are permitting other scientists to use the system for similar projects. They hope the method will be used for other species to record animal behavior and monitor different animal populations in the environment.

10 . Is it to their body temperature? Save energy? Find food? Tiger sharks at Ninglaoo Reef are thought to search the seafloor for prey(猎物) as they dive down and scan for direction as they swim up to the surface. But could there be other reasons why the sharks continuously move up and down?

That’s what Sammy is hoping to find out for her Ph.D. research. Sammy attached tracking devices to 24 tiger sharks. Best described as Fitbits for sharks, the devices recorded activity rates and other data 20 times a second. Fitbits also contained video cameras, so Sammy could see the habitats the sharks moved through and the animals they met. She watched how the sharks reached to prey and how the prey reached to them.

Tiger sharks can be pretty lazy --- something as simple as a turtle noticing a shark and turning away could cause the shark not to bother hunting it. Stomach content analysis has found their normal prey items, such as turtles, rays and fish. But it has also found some really interesting things, such as licenses, cans and nails.

Sammy says that studying tiger sharks can help her better understand the ecosystem as a whole. How they move through water and feed can help her figure out how they might be influencing animals beneath them in the food chain.

“My time watching tiger sharks hunt was the best month of my Ph.D., if not any life.” Sammy says. “At first, I was a bit apprehensive about it...getting that close to some very big animals. But they were very chilled(温驯) once you had them controlled alongside the boat. They’d just sit there, you’d attached the tracking devices, you’d take the line off and they’d just swim off really calmly, it was pretty amazing to see. They’re just absolutely beautiful animals.”