.... engine are slowly deteriorating our lungs and our atmosphere. The exhaust is extremely toxic to human beings. But why do we do continue to drive these walking time bombs. Some people will say it is progress, but the majority drives it for the convenience. Why walk four miles in four hours when you can drive the same miles in four minutes? Another popular source of waste is the post-consumer market. American citizens throw away millions of tons of garbage each year, and this trash has to go somewhere. While there are projects underway to clean and reuse this refuse most of it gets dumped into huge landfills. These landfills are disgusting festering bl .....

.... of the carbon-14 in a fossil decays to nitrogen-14. Since the ratio of carbon-12 to carbon-14 in a living organism remains the same as in the environment around them because the organism constantly eats and replenishes it, if it were to die, the ratio would change greatly after many years. It is the difference between this ratio now and the time is died that allows a date for it to be established. Potassium-argon dating, another dating method, is possible due to volcanic ash and rocks found near many fossil sites. Rocks and ash created in this manner contain potassium-40, but no argon. As time passes, the potassium-40 decays into argon-40. In th .....

.... have been the only ways to galvanize action towards altering and limiting technologies so that adverse chemicals and substances are no longer belched into the environment. For example, Sagan is right on the mark when he indicates that it took the reality that CFCs were destroying the sensitive but protective ozone layer to encourage large chemical companies to begin a gradual phase-out of these substances, even when scientists had already discovered the terrible effects of the chemical combination. Sagan says that to slowly stop usage of such obviously dangerous substances is not enough, for even with current conditions, it is estimated that the d .....

.... bear you will probably notice that it is bowlegged. This means that their huge paws point inward. Having their paws in this position helps them grip the slippery ice. Another specialized feature of its paws is that they have pads of dense fur on the bottoms. Polar bears are the only bears that have this feature. These pads help the bear retain heat and to grip the ice and provide better traction. Polar bears are fast movers. When on uneven ice the bear will “trot�, moving its legs on opposite sides in unison. It can trot at 12 to 18 miles per hour. When it is running, it can reach speeds of up to 35 miles per hour. The bear can trav .....

.... as possible to prove Parents' Magazine wrong. I found several medical journals, psychiatric journals, and books on the topic of eating disorders that could affirm my feelings. As I tried to rationalize my friend's behavior, I decided that social acceptability had to have played a large part in her illness. I also took into account that her mother had passed away about 7 years before she broke her news to me, and she had also given up her crown as Miss Iowa, so depression could have been a factor as well. Another aspect of eating disorders that I discovered is a lack of self-esteem, something I never imagined. The first so .....

.... the fuel cell stacks were tremendous. By 1983, Geoff Ballard and a small team of physicists were able to develop the Proton Exchange Membrane (PEM) to produce nearly ten times as much energy, while being only a fraction of the size. How the PEM Fuel Cell Works: A fuel cell is an electrochemical device that produces electricity silently, without combustion. Hydrogen fuel, which is one of the most abundant chemicals in the universe, and oxygen from the air are electrochemically combined in the fuel cell to produce electricity. Heat and pure water vapour are the only by-products of the fuel cell. The Ballard Fuel Cell is made up of two electrodes, the .....

.... is referred to as dose and duration. The amount of the pollutant administered over what period of time greatly affects the impact that the pollutant will have on an ecosystem and population. Pollutants can affect both a population and an ecosystem. A pollutant on a population level can be either non-target or target. Target effects are those that can kill off the entire population. Non-target effects are those that effects a significant number of individuals and spreads over to other individuals, such is the case when crop dusters spread herbicides, insecticides. Next we look at population damage by a pollutant, which in turn has a detrimental effe .....

.... for the flu is very simple, but finding a vaccine for influenza is virtually nil. Another cause of the is the Antibody for specific virus. Dr Stone thinks that the accumulation of stress tips the infected person over into illness. In his study of 72 married white men for a period of 12 weeks, in which they kept daily diaries of their stress. Researchers then measured the subjects' saliva for a substance called secretary immunoglbulin-A antibody, the less they had of it, the more likely it was that the subject would come down with the cold. This may be true according with Dr. Stone, but an argument made by Dr. Gwaltney, "You see, you could have a .....

.... the human mind. If one looks closely at the capabilities of the human mind and compares them to the most recent technological advances, then it would be obvious that computers and software are beginning to mimic even the most advanced mental states. In the future, computers will be able to do anything the human mind is capable of thus proving Eliminative Materialism to be a sound solution to the mind-body problem. Most of the day the human mind is taking in information, analyzing it, storing it accordingly, and recalling past knowledge to solve problems logically. This is similar to the life of any computer. Humans gain information through the se .....

.... indicated that memory for pictures and words, whether they were initially named or categorized had an effect on memory. Memory was better for words if they have been categorized and for pictures if they have been named. Experiment 3 showed the same results as the previous two experiments. The fourth experiment, with the introduction of less common objects, subjects could name the words faster than generating a category name for the words. Naming pictures are prone to interference when incongruent words are presented simultaneously. Word naming is not as much influenced by distracting pictures. Pictures and words differ in the amount o .....