You're rushing to work and a man ahead of you falls down on the sidewalk. Do you stop to help? In a study of by-standers, it was found that some people keep on walking.

    "There is a tendency to decide that no action is needed," says a psychologist, "In order to take action, you have to work against them." Here are some common thoughts that stop you from helping.

    ●Why should I be the one? I'm probably not the most able person in this crowd. You might think someone older or with more medical knowledge should offer assistance.

    ●What if he doesn't really need my help? The fear of embarrassment is powerful; no one wants to risk looking foolish in front of others.

    ●No one else looks concerned. We can follow the people around us, but most people tend to hold back their emotions in public.

    "If you spot trouble and find yourself explaining inaction, force yourself to stop and evaluate the situation instead of walking on," says the psychologist. "Then retry to involve other people; you don't have to take on the entire responsibility of being helpful. Sometimes it's just a matter of turning to the person next to you and saying, 'It looks like we should do something.' Or asking someone if an ambulance has been called and, if not, to call for one. Once you take action, most people will follow you."

    E-mail has been widely used since its invention for its convenience, efficiency, and high speed. However, it is wise to remember how easily this wonderful technology can be misused, sometimes unintentionally, but can result in serious consequences.

    Now let's look at the case of the Illinois man who left the snow-filled streets of Chicago for a vacation in Florida. His wife was on a business trip and was planning to meet him there the next day. When he reached his hotel , he decided to send his wife a quick E-mail. Unable to find the note with his wife's E-mail address, he did his best to type from his memory. Unfortunately, he missed one letter and his E-mail was directed to an elderly lady whose husband had passed away (去世) only the day before. When the sad widow checked her E-mail, she took one look at the screen, let out a sharp cry, and fell to the floor in a dead faint (昏迷 ). At the sound , her family rushed into the room and saw this note on the screen:

    MY DEAREST WIFE： JUST GOT CHECKED IN. EVERYTHING PREPARED FOR YOUR ARRIVAL TOMORROW.

    P.S. SURE IS HOT DOWN HERE

    Rome, Paris and New York are the world's top fashion cities, all of which have produced some of the top trends, from fashionable skirts to the hottest new shoes. But have you ever wondered about the negative ideas that they have enforced?

    In April 2016, the Advertising Standards Authority (ASA) in Britain banned an ad from Gucci that featured models dancing around and having fun, because they were all extremely skinny. Banning ads due to the models' extreme figures isn't new. The ASA banned an ad in 2015 for the same reason. In France, it has been ruled that models are to provide a doctor's note providing that they are at a healthy weight.

    So what is the healthy weight for models? Twenty years ago, the average fashion model weighed 8% less than the average woman. Today, they weigh 23% less.

    People may think that being at an unhealthy weight will help them gain the benefits that the models do. This provides a standard of beauty, and therefore people who want to achieve those things may attempt to obtain them through unhealthy ways. People may think that they are overweight, due to the images of models¹ thin figures. They see something wrong with their bodies, whether they are overweight or not. This is a key factor in a lowered body image, low self-esteem, depression and possibly even eating disorders.

    I'm not blaming the fashion industry by any means. It's not their fault that many people look up to the models and expect to live a life like theirs. I am glad that the ASA is raising its voices when discussing the growing issue of body images in the fashion industry. By banning photos and videos, speaking out against them and pushing for doctor's notes from the models, it's pushing for the ideas that the traditional fashion industry's body image demands should be changed and something more needs to be questioned.

    A research project jointly carried out by scientists from several British universities and institutes has drawn people's attention to the toothbrush again.

    Researchers have found that your toothbrush is home to more than 100 million bacteria. But there are hundreds of microorganisms in the mouths and your toothbrush probably won't make you sick unless there is an unhealthy balance of bacteria. Our immune system can usually take care of bacterial invaders. However, if others use your toothbrush, or you use someone else's, bacteria can be spread.

    They have also found the toothbrush holders are the third-most dirty household items (behind dish sponges and kitchen sinks), thus advocating cleaning the toothbrush holder regularly.

    The storage of your toothbrush in your bathroom is also important. Here are some storage tips from the researchers to keep your toothbrush as healthy as possible:

    Put your toothbrush as far away as possible from the toilet flushing.

    Let your toothbrush dry thoroughly between brushings.

    Don't use toothbrush covers, which can create a perfect breeding ground for bacteria.

    Keep your toothbrush upright in a holder rather than lying down.

    Keep toothbrushes separate. If toothbrushes touch, they can exchange and spread bacteria.

    There are products available that claim to sanitize（消毒）your toothbrush. While some of these products do kill some bacteria, there is no evidence that using them will reduce your risk of illness, according to the researchers.

    They recommend replacing your toothbrush every three to four months or more often if you are sick or if you have a weakened immune system. Children's toothbrushes may need to be replaced more often than adult brushes.

    The "Give It Up for Earth Day" encourages people to commit to giving up actions that are harmful to the environment, such as using poisonous cleaners.

    Throughout the month of April, Canadians are being asked to "Give It Up for Earth Day!" Earth Day has been celebrated every year on April 22 since 1970. Earth Day Canada president Jed Goldberg says that as people become more environmentally aware, they want to find ways to reduce their environmental influence, not just celebrate one special event.

    "Earth Day is a great launching pad for thinking about environmental action every day," said Goldberg. "Choosing healthier options, even for the short term, can lead to thinking about the influence of our decisions for a lifetime."

    That's the reason behind the "Give It Up for Earth Day" campaign. It's designed to encourage healthy habits that benefit people and the planet. It challenges everyone to help create a healthier world by making changes in their daily routine.

    "We wanted to plan an action—targeted campaign that will give people a chance to act on their concern for the environment in a positive way," said Goldberg.

    The campaign has identified four daily actions that can add up to huge environmental savings. They include pledging (保证) to turn off the TV, give up the use of poisonous cleaners, reduce consumption of consumer products and cut out meat.

    At the end of April, all of the pledges will be recorded and converted (转化) into the number of TV hours not watched, dollars not spent on unnecessary items, electricity saved, greenhouse gas emissions (排放) avoided by cutting out meat, and poisonous chemicals produced from homes and landfills.

    "What we're trying to achieve this year for Earth Day is to give people a chance to do something that is meaningful and measurable," said Goldberg.

Accines (疫苗) may soon make their first film appearance. Led by expert Maria A. Croyle, researchers have developed a thin sheet that preserves vaccines for long periods without refrigeration. This means the carefully cooled small bottles now used to ship vaccines could potentially be replaced by lightweight films that can be mailed in an envelope and stored on a shelf.

Croyle's laboratory began developing the technology in 2007. Inspired by amber's ability to preserve the DNA of insects, the researchers set out to create their own version of the substance by mixing "a lot of sugar and a little bit of salt, much like hard candy," Croyle explains. The vaccine-containing film is administered by mouth—sweet news for many who dislike needles.

The film is tailored to suit each specific vaccine candidate and provide a protective coating. "We've learned over time that the key to really stabilizing whatever the film holds is to have it intermixed with all the components," Croyle says, adding that the process is quick and uses affordable, standard equipment. "We really wanted to come up with something that would be transferable to developing countries."

Immunization(免疫) programs depend heavily on keeping vaccines cold(2℃-8℃) as they are transported, sometimes over thousands of kilometers to far-away locations. Delivery can be difficult and costly, and transport disruptions can cause the vaccines to be ineffective.

But this new product can store live viruses, bacteria and antibodies for several months at 20℃. In a paper published in Science Advances, the scientists show that the live viruses in one vaccine were preserved in the film even after 36 months. They also find that a flu vaccine suspended in their film compares favourably with a traditional flu shot(流感预防针). "The study demonstrates early proof of concept for an exciting platform for vaccine product development," says Lisa Rohan, a pharmacologist, who was not involved in the study. She also notes that each vaccine type would need a custom formulation(配方) for future stages of development.

Finding partners to mass-produce for clinical trials is the researchers' most pressing problem, Croyle says. They are also exploring packaging methods to keep their films stable up to 40℃.

Size is a major advantage—a letter-sized sheet of the film can carry more than 500 doses(剂) of vaccine, about 1⁄900 the weight of the same amount of traditional doses. By making it easier and cheaper to ship and preserve vaccines efficiently, Croyle says, the technology could vastly improve immunization rates the world over, particularly in middle- to low- income countries.