Batteries can power anything from small sensors to large systems. While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves. University of Missouri(MU) researchers are developing a nuclear energy source that is smaller, lighter and more efficient.

    “To provide enough power, we need certain methods with high energy density (密度)”，said Jae Kwon, assistant professor of electrical and computer engineering at MU. “The radioisotope (放射性同位素) battery can provide power density that is much higher than chemical batteries.”

    Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro/nanoelectromechanreal systems (MNEMS) Although nuclear batteries can cause concerns, Kwon said they are safe.

    “People hear the word 'nuclear' and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems.”

    His new idea is not only in the battery's size, but also in its semiconductor(半导体). Kwon's battery uses a liquid semiconductor rather than a solid semiconductor.

    “The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure(晶体结构) of the solid semiconductor,” Kwon said, “By using a liquid semiconductor, we believe we can minimize that problem.”

    Together with J. David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery, In the future, they hope to increase the battery's power, shrink its size and try with various other materials. Kwon said that battery could be thinner than the thickness of human hair.

    First aid is emergency care for a victim of sudden illness or injury until more skillful medical treatment is available. It may save a life or improve certain vital signs including pulse, temperature，a clear airway(气道), and breathing. In minor emergencies，first aid may prevent a victim's condition from turning worse and provide relief from pain. First aid must be   administered as quickly as possible. In the case of the Critically injured, a few minutes can make a difference between complete recovery and loss of life.

    First­aid measures depend upon a victim's needs and the provider's level of knowledge and skill. Knowing what not to do in an emergency is as important as knowing what to do. Improperly moving a person with a neck injury, for example，can lead to permanent spinal (脊柱的) injury and  paralysis (瘫痪)．

    Despite the variety of injuries possible, several principles of first aid apply to all emergencies. The first step is to call for professional medical help. The victim, if conscious（有意识的）, should be reassured that medical aid has been requested，and asked for permission to provide any first aid.  Next，assess the scene, asking other people or the injured  person's family or friends about details of the injury or illness，any care that may have already been given, and preexisting conditions such as diabetes (糖尿病) or heart trouble. The victim should be checked for a medical bracelet (手镯) or card that describes special medical conditions. Unless the accident scene becomes unsafe or the victim may suffer further injury，do not move the victim.

    First aid requires rapid assessment of victims to determine whether life­threatening conditions exist. One method for evaluating a victim's condition is known by the acronym(首字母缩写词)ABC，which stands for：

    A—Airway: Is it open and clear?

    B—Breathing: Is the person breathing? Look, listen, and feel for breathing.

    C—Circulation: Is there a pulse? Is the person bleeding externally? Check skin color and temperature for additional indications of circulation problems.

    Anyone can try to lead a group, but not every individual is cut out for leadership. The better leaders possess a few qualities that can mean the difference between the success and failure of the group. These are the qualities the leader of higher rank will look for when choosing a leader for a group, or when evaluating the performance of a leader. They're also the qualities team members want in a group leader, and appreciate when they find them.

    Take Responsibility

    Group leaders might share tasks around a group as necessary, but eventually a group leader needs to be able to accept that responsibility lies on his shoulders. That means that if things go wrong in a group project, he's the one who must accept the consequences and work out what mistakes are made. The group leader won't always have the power to control everything group members do, but he should be ready to admit any mistakes the group has made as a result of his leadership

    Concern for Members

    The group leader has a commitment to the task or project at hand, but perhaps more importantly, he has a real concern for each and every person who is part of his group. This means getting to know the strengths, weaknesses and goals of team members, as well as making time to build the group through collective activities. The group leader should make sure that everyone is included, even if an individual is new to a group.

    Good Listener

    The group leader needs to be able to listen to the suggestions, complaints and ideas of group members. Not only will this allow complaints to be addressed and potentially suitable ideas to be put into practice, but a leader who listens will also encourage group members to share their concerns and thoughts, creating an atmosphere of free speech and productivity.

    Behind most of the bad things we do to our bodies as adults, eating more than we should is the idea we carry with us from childhood. On one hand, we assume that we are indestructible. On the other hand, we think that any damage we impose on ourselves can be undone when wβfinally clean up our act.

    If the evidence for how wrong the first idea is isn't apparent when you stand naked in front of the mirror, just wait. But what if you eat right and drop all your bad habits? Is there still time to repair the damage?

    To a surprising degree, the answer is yes. Over the past five years, scientists have collected a wealth of data about what happens when aging people with bad habits decide to turn their lives around.

    The heartening conclusion: the body has an amazing ability to heal itself, provided the damage is not too great.

    The effects of some bad habits-smoking, in particular-can haunt you for decades. But the damage from other habits can be largely healed.

    “Any time you improve your behavior and make lifestyle changes, they make a difference from that point on.” says Dr. Jeffey Koplan. “Maybe not right away. It's like slamming on the brakes. You do need a certain distance.”

But the distance can be remarkably short. Consider the recent announcements from the front lines of medical research: —A study concluded that women who consume as little as two servings of fish a week cut their risk of suffering a stroke to half that of women who eat less than one serving of fish a month. —The day you quit smoking, the carbon monoxide levels in your body drop dramatically. Within weeks, your blood becomes less sticky and your risk of dying from a heart attack starts to decline ... Adopting healthy habits won't cure all that bothers you, of course. But doctors believe that many chronic diseases-from high blood pressure to heart disease and even some cancers-can be warded off with a few sensible changes in lifestyle.

    Not sure where to start? Surprisingly, it doesn't matter, since one positive change usually leads to another. Make enough changes, and you'll discover you've adopted a new way of life.

Most of the 20th century has been a development on the Industrial Revolution taken to an extreme: people now own more products than ever before; there are enough unclear weapons to destroy the earth several times over; there is hardly any forest left and pollution has got to the point where we buy water. Within a few years I predict you will be able to buy air. (There once was a time when you didn't need to buy food or shelter either.)

Important developments in the last century are the breaking down of the class structures left over from the Industrial Revolution stage, bringing with it the empowerment of the "common man": the working day is set by law to only 8 hours a day; everyone has the vote; the media has less obvious government control; people have landed on the moon, sent spacecrafts to Mars and so on. Families have also shrunk drastically (强烈地); the nuclear family came about, and especially in the last half of the 20th century, one­parent families are becoming more common. This shrinking in the size of the family shows the increased independence of people — once upon a time people had to live in large groups to survive.

As humans have "become the gods", they have realized their individuality and independence and taken their control of the world to an extreme. In many countries the land is almost completely used in the production of food and as living space and they live in small cities which are entirely human constructed, made from materials which are also entirely human constructed (concrete bricks) with hardly any remains of nature. Weeds are poisoned because they are messy; even parks have trees grown in tidy lines; grass is mowed to keep it short and so on. I think the massive drug "problem" troubling people is a result of too much of this influence, humans needing to escape the stark world they have created by entering fantasy worlds.

Over the last 100 years, the 20th century consciousness has spread throughout the world; most of Asia has been thoroughly "Westernized", and most of the Third World is being overrun by Western ways of doing things and living.

Narayana Peesapaty was sitting on a flight when he noticed a passenger trying to reach food with a biscuit after breaking his spoon. At that moment, the researcher's mind gave birth to a simple yet revolutionary concept — edible spoons.

How do you like your spoon?

Peesapaty's company, Bakeys, makes edible spoons mainly out of sorghum(高粱）though rice, wheat and water are also ingredients. They combine to form a dry eating tool that remains hard even when used in moist or hot foods. Bakeys also makes ginger and garlic flavored(风味) spoons to meet specific requests. All spoons are completely natural and acceptable for nearly all diets.

A rice replacement

An environmentally-minded water researcher, Peesapaty, designed his spoons to be eco-friendly in several ways. Sorghum was chosen as the main ingredient of the spoons instead of rice, which requires 60 times as much water. Sorghum was also chosen for the strength it would lend eating tool, and the grain requires little water, low energy and no chemicals to grow.

In place of plastic

The goal that Peesapaty hopes to attain through Bakeys is to prevent plastic from any contact with food. Plastic products can contain cancer-causing substances that come into food, and average plastic bottles take 450 years to break down. In contrast, a Bakeys' spoon is nutritious and break down in 10 days or less if thrown away. Peesapaty admits that using plastic is cheaper, but he also says that his spoons will be equally inexpensive when mass-produced.