By now, we are all aware that social media has had a powerful 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, besides seeing your friends' 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 reconnect 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 take part in campaigns and activities of their choice. Professionals use social media sites like Linkedln to improve 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(网络欺凌) 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 (分心)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 Net can come back to trouble you. Leaking personal information on social sites can make users easily harmed to crimes like identity theft, stalking(尾随犯罪), etc. Many companies perform a background check on the Web 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 improve their professional and social life, and exercise caution to ensure they do not fall victim to online dangers.

    An autonomous vehicle designed for making local commerce deliveries was unveiled by Nuro. The vehicle is about the height of an SW but far narrower than a typical car. The electric car features four exterior compartments (暗格) — two on each side — to hold separate deliveries. Each compartment can be tailored to a specific use, such as cooking a pizza or refrigerating a package.

    “We can use self-driving technology to deliver anything, anytime, anywhere for basically all local goods and services,” Nuro co-founder Dave Ferguson said. “Consumers used to be okay with two-week paid shipping. It became two-week free delivery, followed by one week, two days, and the same day. Now same-day delivery isn't fast enough for some customers.”

    Nuro isn't alone in building robots for local commerce deliveries. Earlier this month, Toyota, a Japanese car company, unveiled a concept vehicle that could be used for package delivery. A handful of startups — including Starship Technologies, Marble and Dispatch — are testing small robots for deliveries on sidewalks.

    Nuro's vehicle will likely face legal hurdles. Fully autonomous vehicles without a test driver aren't legal in California today, and many companies have shifted testing to states where regulators are more welcoming of autonomous vehicles, such as Arizona.

    Nuro expects to face fewer challenges because it doesn't carry passengers. Nuro's narrow size may also be helpful when navigating streets and avoiding pedestrians. The vehicle isn't equipped with any special features to communicate with pedestrians or other road users. Some companies have tested and patented solutions such as digital screens that signal the car's next move. Ferguson said his team conducted studies and found that such techniques could confuse people. Nuro believes it's better to make sure the car performs predictably, so that human drivers know what to expect from it.

    “We feel by creating this new technology that's going to enable this last mile delivery, we're going to be creating new markets and doing things that previously weren't possible,” Ferguson said. “This is not swapping out Jobs with robots. It's creating new markets. There will definitely be new employment opportunities.”

    Staying up late is a potential battle between parents and kids. But the solution could be as simple as changing your meal time.

    Researchers at the University of Surrey, UK, found that delaying (延迟) meals could help change one of the internal (内部的) body clocks. Besides a “master” clock in the brain, there are clocks in other parts of the body. They are usually synchronized (同步的) according to factors including light.

    During the study, researchers tested 10 participants to study the effect of changing meal times on their body clocks. The participants were given three meals – breakfast, lunch and dinner. In the first stage, participants received breakfast 30 minutes after waking. Lunch and dinner followed, after 5-hour intervals (间隔). In the second stage, each meal was delayed by 5 hours. Right after each stage, blood and fat samples (样本) were collected.

    Results showed that later meal times greatly influenced blood sugar levels. A 5-hour delay in meal times caused a 5-hour delay in the internal blood sugar rhythms (规律性变化).

    The discovery showed that meal times are in line with (与……一致) the body clock that controls blood sugar levels.

    This is a small study but the researchers believed the findings could help jet lag (飞行时差反应) sufferers and night-shift (夜班的) workers.

    In a study by the University of Surrey in 2013, researchers explored what happened when a person's body was changed from a normal pattern to that of a night-shift worker's.

    After people work through the night, over 97 percent of the body's rhythmic genes are disrupted (扰乱).

    These findings explain why we feel so bad following a long flight, or after working at night, according to Simon Archer, one of the study's researchers.

    “It's like living in a house. There's a clock in every room in the house and in all of those rooms those clocks are now disrupted, which of course leads to chaos (混乱) in the household,” fellow researcher Derk-Jan Dijk told the BBC.

    Changing meal times didn't affect the “master” body clock – the one controlling when we get sleepy – but it can reset the body clock that controls blood sugar levels.

    This wouldn't necessarily cure jet lag completely, but it might reduce the negative effects.

    A study published earlier this year suggested that just a weekend camping trip could be enough to reset our body clocks. And now this latest research shows regular food schedules could play a key part too.

    My friend Susan has a huge-hearted husband. He is once again on the front lines of fighting the fires in Northern CA. As a Chief Battalion leader, his job is very dangerous and his time away from his family is often for weeks at a time during "fire season".

Every time before he leaves, Ethan, Susan and each of the three teens hold one another and thoughtfully each shares the best of their traditions — each promises to do the tasks that will keep the family a well-oiled machine while Ethan is away.

    Ethan has brought back animals that lost their homes in the fires. By now, a gray rabbit, two parrots and a small group of Nubian goats have been added into the family.

    When Ethan is on duty, Susan keeps checking her cell phone for Ethan's text messages. His substantial (大量的) white facial hair is often mistaken for that of Father Christmas by children who are carried out of their burning homes by him.

    For each rescued child, a toy bear is waiting to be matched with him/her. For each adult, Ethan provides clean clothes. He finds pleasure in doing his job well. He is grateful to be often on the front line with frightened people and their poor pets.

    I am mentioning Ethan because by now the big fire has been spreading widely for a week. It has caused 55 deaths and left 500,000 people homeless. Now I am here at my school site, and the smoky air is keeping our students inside, waiting for rescue.

    What do you do when you need to look something up? Go to the library? Open an encyclopedia(百科全书)? Click onto the Internet? These days, most people go straight to Wikipedia, the online encyclopedia. But how reliable is it?

    There's no denying the popularity and usefulness of Wikipedia. It attracts as many as 78 million visitors every month, and the site is available in more than 270 different languages. It's one of the most comprehensive resources available, which includes almost all details, facts and information that may be concerned. It's got much more information than an ordinary encyclopedia. The site is updated on a daily basis by thousands of people around the world. Anyone with an Internet connection can log on and edit the contents or add a new page. And you don't need any formal training.

Of course, there are some controls. Wikipedia has a team of more than 1,500 administrators who check for false information. And main targets for harmful comments(such as politicians) are off-limits to public editing. But with more than 16 million articles to keep an eye on, it isn't easy. So, while Wikipedia benefits from being constantly updated with information from all over the world, it's also open to “vandals”（恣意破坏公共财物者）.

    Some of the damage is easy to notice. One person drew devil horns and a moustache on Microsoft chairman Bill Gate's photo, while another edited Greek philosopher Plato's biography to say he was a “Hawaiian weather man who is widely believed to have been a student of 'Barney the purple Dinosaur'.

    But other things are harder to spot. The most common form of vandalism (恣意破坏公共财物罪)involves adding tiny items of false information into the biography of a famous person. Unbelievably, some of this misinformation has appeared in newspapers, with The Daily Mail, The Guardian and The Independent all having fallen victim to the dirty tricks. For example, in an article about British comedian Sir Norman Wisdom, one newspaper claimed that he co-wrote Dame Vera Lynn's wartime hit There'll be bluebirds over the White Cliffs of Dover. He did no such thing. And in other article, it was reported that TV Theme tune composer Ronnie Hazlehurst had written the S Club 7's hit Reach again, not true. So, if you're going to use any information from Wikipedia, make sure you double-check it first.

    Self-driving cars have been backed by the hope that they will save lives by getting involved in fewer crashes with fewer injuries and deaths than human-driven cars. But so far, most comparisons between human drivers and automated vehicles have been unfair.

    Crash statistics for human-driven cars are gathered from all sorts of driving situations, and on all types of roads. However, most of the data on self-driving cars' safety have been recorded often in good weather and on highways, where the most important tasks are staying in the car's own lane and not getting too close to the vehicle ahead. Automated cars are good at those tasks, but so are humans.

    It is true that self-driving cars don't get tired, angry, frustrated or drunk. But neither can they yet react to uncertain situations with the same skill or anticipation of an attentive human driver. Nor do they possess the foresight to avoid potential perils. They largely drive from moment to moment, rather than think ahead to possible events literally down the road.

    To a self-driving car, a bus full of people might appear quite similar to an uninhabited corn field. Indeed, deciding what action to take in an emergency is difficult for humans, but drivers have sacrificed themselves for the greater good of others. An automated system's limited understanding of the world means it will almost never evaluate (评估) a situation the same way a human would. And machines can't be programmed in advance to handle every imaginable set of events.

    Some people may argue that the promise of simply reducing the number of injuries and deaths is enough to support driverless cars. But experience from aviation (航空) shows that as new automated systems are introduced, there is often an increase in the rate of disasters.

    Therefore comparisons between humans and automated vehicles have to be performed carefully. To fairly evaluate driverless cars on how well they fulfill their promise of improved safety, it's important to ensure the data being presented actually provide a true comparison. After all, choosing to replace humans with automation has more effects than simply a one-for-one exchange.