There are two ways of driving in the world: if the driver's seat is on the left and cars travel on the right side of the road, it is called “left-hand driving”, as it is in China, while the other way of driving is called “right-hand driving”, as it is in Britain. Nowadays, around 65% of the world's population drives on the right of the road, while the rest is used to driving on the left.

    Though no one knows the exact reasons, it seems likely that people in ancient times travelled on the left. Roman coins show pictures of horsemen passing on each other's right. And right-hand people generally got on a horse from the animal's left. Obviously, it's safer to do this at the left side of the road, and it makes sense for the horse to be ridden on the left.

    A change happened in the late 1700s. When Napoleon conquered nations, he forced them to travel on the right side of the road, which spread left-hand driving throughout Europe. However, Britain still stuck with the right-hand driving rule and countries which were part of the British Empire (帝国) were made to follow. This is why India, Australia and the former British colonies (殖民地) in Africa continue to drive on the left. One exception is Egypt, as that country was defeated by Napoleon before becoming part of the British Empire.

    Some countries changed sides' until modem times. Sweden only moved to driving on the right in 1967 and Iceland changed the following year. Ghana changed sides in 1974. On September 7,2009, Samoa became the third country ever to change from left-to-right-hand driving for the reason that it made it easier to import (进口) cheap cars from right-hand driving Japan, Australia and New Zealand.

    So if you want to travel to another country or go on business, make sure you know whether it is left-or right- hand driving to avoid unnecessary troubles.

Reader's Travel Photography Competition

    This month's images include some original and brilliant shots. The overall 2018 winner will receive a $200 holiday ticket and go on a 16-night wildlife holiday.

    October 15^th is the Global Handwashing Day. Activities are planned in more than 20 countries to get millions of people in the developing world to wash their hands with soap. For example, donators (捐赠者) will give 150,000 bars of soap to schools in Ethiopia.

    Experts say people around the world wash their hands every day, but very few use soap at so-called important moments. These include after washing the toilet, after cleaning a baby and before touching food.

    Global Handwashing Day is the idea of the Public-Private Partnership for Handwashing with Soap. Partners include the United Nations Children's Fund, American government agencies, the World Bank and soap makers Unlever and Procter and Gamble. The organizers say all soaps are equally effective at removing disease-causing germs(细菌). They say the correct way to wash is to wet your hands with a small amount of water and cover them with soap. Rub(揉搓) it into all areas, including under the fingernails. Rub for at least twenty seconds. Then rinse well under running water. At last, dry your hands with a clean cloth or wave them in the air.

    The Partnership for Handwashing says soap is important because it increases the time that people spend in washing hands. Soap also helps to break up the dirt that holds most of the germs. And it usually leaves a pleasant smell. The Partnership for Handwashing also says washing with soap before eating or after using the toilet could save more lives than any vaccine(疫苗) or medicine. Hand washing could also prevent the spread of other diseases. When people get germs on their hands, they can infect(感染) themselves by touching their eyes, noses or mouths. Then they can infect others.

The world has been extremely impressed by China's high-speed trains that cross the country by the hundreds in all directions every day, but in one corner of this vast land is a gentle reminder that life was not always this fast.

Those fortunate enough to travel to Jiayang in Sichuan province will find railway carriages dragged by steam locomotives(火车头), among the last steam trains operating in China and still running every day. First used to transport coal from Jiayang Coal Mine 62 years ago, today they transport local farmers and their produce to market and serve as a tourist attraction.

"In the early days of the railway, farmers headed for the farm produce market sitting beside coal," said Liu Chengxi, the Jiayang official in charge of the trains. "As coal production has stopped, the trains are now exclusively(专门地)for farmers and tourists."

The narrow railway, only 76.2 cm instead of the standard 144 cm, stretches for 19. 84 km, with the trains reaching a top speed of 20 km/h.

A one-way ticket costs 5 yuan for seated passengers and 3 yuan for standing passengers on the ordinary trains regardless of whether they are travelling empty-handed or with animals or vegetables. But Li Cuirong, who has worked as a train dispatcher(调度员)for more than 20 years, recommends tourists pay 80 yuan for a sightseeing train, as the carriages, which have 37 seats, are more comfortable and air-conditioned. A one-way trip takes about one and a half hours.

The scenery is dramatic as the train winds through the mountain, passengers can view chickens and geese wandering among the orange trees and butterflies dancing over the fields and ponds.

Rob Dickinson, a steam train lover from the United Kingdom, has ridden the trains twice. He hopes the narrow line can last long enough for him to find the time to get back again.

Anew study suggests that Medicare could spend billions of dollars on screening (拍片检查) smokers for lung cancer that would be better spent on helping them quit and keeping others from starting.

The new study indicated that screening more often supported smokers' beliefs that they could safely continue to smoke. Most participants remained smoking because they believed screening could catch cancer early before it would threaten their lives.

"They compared how hard it was to quit smoking with how easy it was to be screened," said Steven B. Zeliadt, the lead author of the study." They engaged in magical thinking that now there's this wonderful painless external test that can save lives."

He and seven colleagues conducted the study of 37 current smokers who were offered lung cancer screening at Department of Veteran Affairs. After being screened and told the results, they were interviewed about their smoking-related heath beliefs. For about half of those, cancer was not found." Screening lowered their motivation for quitting," the team reported in July in JAMA Internal Medicine. The participants focused only on lung cancer, ignoring other potential harm of smoking.

A national study published four years ago found that annual CT screening for lung cancer three years in a row could reduce deaths among heavy smokers by about 20 percent. In an interview, Dr. Russell P. Harris, a preventive medicine specialist at the UNC-Chapel Hill, noted that" Screening is being believed by people as an alternative to stopping smoking. But stopping smoking would have huge benefits for the individual and society." Furthermore, smoking causes many other cancers.

Dr. Harris agreed that rather than screening, money is better spent on smoking prevention. He suggested providing free stop-smoking aids, sponsoring anti-smoking advertising and raising taxes on tobacco products and the age at which people are allowed to buy them.

In 1985, 16-year-old Douglas Casa, ran the championship 10, 000 meter track race at the Empire State Games. Suddenly, with just 200 meters to go, he collapsed on the final straightaway, with his body temperature at dangerous levels. He had suffered an exertional heat stroke（运动型中暑）or sunstroke. {#blank#}1{#/blank#}

From ancient soldiers on the battlefield to modern warriors on the gridiron（足球球场）, exertional heat stroke, has long been a serious concern. And unlike classical heat stroke, which affects people such as babies and the elderly during heat waves, exertional heat stroke is caused by intense exercise in the heat. {#blank#}2{#/blank#}

So how do you diagnose an exertional heat stroke? The main criterion is a core body temperature greater than 40℃ along with signs of central nervous system disfunction such as confused behavior, or loss of consciousness. 

As far as treatment goes, the most important thing to remember is cool first, transport second. The human body can withstand a core temperature above 40℃ for about 30 minutes before cell damage sets in. {#blank#}3{#/blank#}After any athletic or protective gear has been removed from the victim, place them in an ice water tub while stirring the water and monitoring vitals continuously. {#blank#}4{#/blank#}As you wait, itˈs important to keep the victim calm while cooling as much surface area as possible until emergency personnel arrive. If medical staff are available on site, cooling should continue until a core temperature of 38. 9℃ is reached. 

{#blank#}5{#/blank#}As Dr. J Levick wrote of exertional heat stroke in 1859, "It strikes down its victim with his full armor on. Youth, health and strength oppose no obstacle to its power. " But donˈt be frightened so much for it has been 100% survivable with proper care.