More people are increasingly biking to commute (上下班往返), for exercise, or just for fun. Bicyclists should observe bicycle safety rules to help reduce deaths and injuries on the road.

Every bike ride begins with putting on a helmet. Your helmet can best protect you. For the most comprehensive list of helmet sizes according to manufacturers, click here to visit the Bicycle Helmet Safety Institute (BHSI) website.

There are two main types of crashes: the most common (falls) , and the most serious (the ones with cars). Regardless of the reasons for the crash, prevention is the key point.

Be alert to the road and all traffic around you; anticipate what others may do before they do it. This is defensive driving — the quicker you notice a potential conflict, the quicker you can act to avoid a potential crash.

Obey street signs, signals, and road markings, just like a car. Look ahead for risks or situations to avoid what may cause you to fall, like potholes (坑洼) and train tracks. No texting, listening to music or using anything that distracts you by taking your eyes and ears or your mind off the road and traffic.

This way, if the sidewalk ends, you are already riding with the flow of traffic. If crossing a street, motorists will look left, right, left for traffic. When you are to the driver’s left, the driver is more likely to see you. Slow and look for traffic (left — right — left and behind) when crossing a street from a sidewalk; be prepared to stop and follow the pedestrian signals.

When you think of art restoration, what comes to mind is probably a group of specialists laboring over paintings with small brushes, making efforts in a museum basement.

So it might come as a surprise that one thing most people think should be kept away from art is what is bringing it back to life: bacteria.

According to Popular Science, specialized microbes (微生物) have been set loose on everything from centuries - old frescoes (壁画) to oil paintings to massive cathedral (大教堂) walls, all in an effort to clean and restore the original glory of these pieces of cultural heritage.

Recently, a team from the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) and restoration collaborators (合作者) were tasked with solving the issue of decaying (腐烂) human remains that were staining (弄脏污染) the Michelangelo - carved marble in the Medici Chapel in Florence, Italy. Several members of the Medici family were buried there.

Anna Rosa Sprocati, a biologist at the ENEA, chose eight of the most promising types of bacteria from a collection of about 1,000 and tested them on the marble. The bacteria successfully removed the contaminants (污染物) while leaving the marble unharmed.

“Biocleaning” - using microorganisms to clean debris (碎屑) from stonework and artwork - was first used in the 1990s by Italian microbiologist Giancarlo Ranalli.

A team was attempting to restore frescoes at the Camposanto Monumentale in Pisa, Italy. When the cemetery was bombed in World War Ⅱ, the remains of the artwork were removed using animal glue to keep the pieces together.

According to Popular Science, after traditional methods of restoration failed, Ranalli said that the project leader turned to him and asked: “But you, Dr Ranalli, can't you do anything with your bugs ?” It turns out bacteria are perfect for this sort of task - but it's important to select the right one. For Ranalli, it was Pseudomonas stutzeri (施氏假单胞菌), type A29. It ate through the animal glue while leaving the original pigments (料). In fact, Pseudomonas stutzeri is used for more than just cleaning up artworks. Their favorite food sources happen to be the same kind of materials that are often found as pollutants, and scientists have grown different kinds of the bacteria to consume specific types of pollution, Forbes reported.

It is indeed the famous artists who create masterpieces, but it's the bugs that keep them good for future generations to appreciate.