Soon computers and other machines will be able to remember you by looking at your eyes! The programme works because everyone's eyes are different. So in the future you won't have to remember a number when you want to use a machine or take money out of a bank. You'll just have to look at the machine and it will be able to tell who you are.
The eye-recognition programme is already being tested in shops and banks in the USA, Britain, Spain, Italy and Turkey. Soon, this technology will take the place of all other ways of finding out who people are.
However, scientists are working on other systems. Machines will soon be able to know you from the shape of your face or hand or even your smell! We already have machines that can tell who you are from your voice or the mark made by your finger.
Eye-recognition is better than other kinds because your eyes don't change as you get older, or get dirty like hands or fingers. And even twins have different eyes, so the programme can be up to 94％ correct, depending on how good the technology is. Some programmes may only be right  51％ of the time. In Britain, it was found that 91％ of people who had tried it said that they liked the idea of eye-recognition. In the future your computer will be looking you in the eye. So smile!

    Could smells affect your lifespan? Female fruit flies (果蝇) without the ability to smell food live longer than other fruit flies．The sense of smell may be connected to the cellular ageing (细胞老化) process in many other living things  even people．Such connection has recently been found in both worms and flies．For example, scientists found that removing fruit flies' ability to smell made them live nearly 20 percent longer than flies with a sense of smell．

    They confirmed that food smells were the ones most likely to affect ageing, as nutrition (营养) and lifespan are known to be connected in many living things．To test the idea that food smells affect lifespan, they removed flies' ability to smell carbon dioxide, which is produced by some fly foods．They left the rest of the smelling system．

    This action had no effect on male flies, but the females lived 30 percent longer than normal．Removing the ability to smell CO₂ may stop flies getting information about food availability．This could mean that food is not enough, causing processes that encourage flies to survive．Scientists found that the female flies from stored extra fat and that both males and females immune (免疫) to CO₂ were stronger against the stress than normal flies．It is suggested that females may simply be easily influenced by the smells of CO₂ ．

    Scientists point out that people don't know whether ageing and smell are connected in animals and humans．But they clearly experience physical changes after smelling food．

    Both seasonal flu, a disease like a very bad cold, and much larger pandemics, like the one caused by H7N9（禽流感） in 2013, are the result of a race between the flu virus  and the immune system which can protect people from illness. Here's how it works.

    Viruses, which cause pandemics, have two important proteins "haemagglutinin(H) and neuraminidase(N).H helps the virus go into a cell .N helps new virus break out of that cell .They are parts of a virus that may be known and dealt with by the immune system

    A flu virus attacks a host cell in order to reproduce itself. But the virus created out of it is quite different now. The virus's genetic material is copied with low fidelity. That difference produces virus which immune system does not always know and deal with immediately. Each year's seasonal virus is therefore a little bit different, and thus requires an updated vaccine to prevent people from getting that disease.

    Pandemics viruses have bigger changes in this process .Many hosts' defences are unprepared for such big changes, which happen three or four times a century .The 1918 pandemics was caused by viruses carrying H1 and N1.Anotber two pandemics in 1957 and 1968 were caused by viruses carrying H2and H3 together with N2.They are numbered by scientists. Much of this change goes on outside humans. A flu is usually from sick binds. Sometimes a bird-flu appears with materiel that enable it to spread among people .The H7N9 is recently worrying scientists in the health center.

    The flu virus sometimes jumps directly from a bird(often a chicken) to a person, but more usually passes through a pig The cells in bird and human are built differently, It means us that the virus needs different sets of material to attack them .Pig cells have features of both so that it can act as a platform in which the virus can fit from one to the other .Even after it has made humans ill, a virus cannot go ca to cause a pandemic unless it also gets the ability to pus easily between people, Luckily, this is something H7N9 has yet to do.

    It is said that more than four million people die each year from smoking. That number is increasing. Seven in ten of those deaths are in developing countries. These numbers are frightening.

    Yet people around the world continue to smoke. The Great American Smokeout has been founded for twenty-five years to show the dangers of smoking and provide support for people who decide to stop smoking. The American Cancer Society says all cigarettes damage the body. It warns that smoking even a small number of cigarettes is dangerous. It is not easy to give up smoking forever. However, doctors say they probably will live longer if they do stop smoking. They will feel better and look better. They also will protect the health of family members who breathe their smoke.

    The American Cancer Society says there is not just one right way to stop smoking. Any useful way to stop smoking is worth trying. They may take long walks or spend time in places where smoking is not allowed. Also, they could eat a small piece of fruit instead of having a cigarette.

    The American Cancer Society says the sooner smokers stop smoking, the more they can reduce their chances of getting cancer and other diseases. It says blood pressure returns to normal twenty minutes after smoking the last cigarette. Carbon monoxide (一氧化碳) gas levels in the blood return to normal after eight hours. After one day, the chance of heart attack decreases. After one year, the risk of heart disease for a non-smoker is half that of a smoker.

Stop smoking before smoking stops you!

    Wind power is a very clean source of energy. This is how wind power works. Wind makes windmills spin (旋转). When the windmills spin, they make electricity. Then we can use the electricity.

    A lot of people think that wind power is new, but that's not true.

    For thousands of years, people have used wind to sail boats and move water. We still do those things today, but these days we mostly use wind power to make electricity.windmills

    Wind power is a very popular source of energy. Most people think that we should use it more and more. First of all, it's clean. Windmills don't pollute the environment at all. Second, we can use wind power forever. After all, we will always have wind. Also, wind power is cheap, and it's getting even cheaper.

    A lot of people don't understand wind power very well. They believe that there are problems with wind power, but many of those problems are not real. For example, some people say that windmills are dangerous for birds. They used to be true, but it isn't true anymore. Old windmills killed birds because they spun very fast. New windmills spin slowly, and they aren't dangerous for birds.

    However, there are real problems with windmills. One problem is that many people think windmills are very ugly. This is a problem for people, because windmills are often in very pretty areas. Also, wind doesn't blow all the time, so we can't use wind power all the time. Finally, windmills are noisy.

    Wind power is becoming more and more common. Right now, more than 80 countries use wind power. About 2.5 percent of the world's power comes from the wind. For some countries, that number is a lot higher. Wind power gives Denmark more than 25 percent of its electricity.

    Earthquakes are hard to predict, but do you know what to do before, during and after an earthquake? Here's some advice:

    Before an earthquake. It's necessary to prepare yourself and your family. All family members should know how to turn off the gas, water and electricity and know useful telephone numbers (120, 110, 119, etc.). Never put heavy things over beds.

    During an earthquake. It's important for each of you to stay calm. If you are indoors, quickly move to a safe place in the room such as under a strong table. The purpose(目的) is to protect yourself from objects. Stay away from windows, large mirrors, heavy furniture and so on. If you're cooking, turn off the gas. If you're outdoors, move to an open area like a playground. Move away from buildings, bridges and trees. If you are driving, stop the car as soon as possible and stay away from bridges and tall buildings.

Stay in your car.

    After an earthquake. Once the shaking has stopped, DO NOT run out of the building at once. It's better to wait and leave when it's safe. Check around you and help the people who are in trouble. If your building is badly broken, leave it. If you smell the gas, get everyone outside and open windows and doors. If you can do it safely, turn off the gas. Report it to the gas company.