.... because it reverses the early decay process as well as creating a tooth surface that is more resistant to decay. Community water fluoridation is the adjustment of the amount of the beneficial trace element fluoride found in water to provide for the proper protection of teeth. Fluoridation has been widely utilized in this country since 1945. It does not involve adding anything to the water that is not already there, since virtually all sources of drinking water in the United States contain some fluoride. Fluoridation is a form of nutritional supplementation that is not unlike the addition of vitamins to milk, breads and fruit drinks; iodine to .....

.... resulted in the successful elimination of such sources of pollution as industrial effluents and the outdoor burning of trash and debris. Nevertheless, pollution continued to increase as a result of the increased number of motor vehicles. Exhaust fumes from the engines of automobiles contain a number of polluting substances, including carbon monoxide and a variety of complex hydrocarbons, nitrogen oxides, and other compounds. When acted upon by sunlight, these substances undergo a change in composition producing the brown, photochemical smog for which Los Angeles is well known. Efforts to reduce pollution from automobile engines and to develop po .....

.... of people being careless. Many times, the chemicals released into the air by people drift into the ozone and form harmful chemical bonds with ozone molecules. One example would be chlorofluorocarbons or CFC's. CFC's were commonly found in spray cans during the early 1970's but were invented in the 1920's. They contain chlorine, fluorine, and carbon atoms which all form bonds with the rare ozone molecules. A few more products with CFC's are coolants for refrigerators and air conditioners, foam products, such as cups, and insulation for houses. Considering that ozone molecules are so rare, it is extremely important to keep them intact. .....

.... affected, but studies suggest that the disease occurs slightly more often in men than in women. Doctors estimate that each year 50 out of every 100,000 Americans have symptoms. Among college students, the rate is several times higher. does not occur in any particular "season," although authorities in colleges and schools, where the disease has been well studied, report that they see most patients in the fall and early spring. Epidemics do not occur, but doctors have reported clustering of cases. Transmission: EBV, the virus that causes most cases of , infects and reproduces in the salivary glands. It also infects white blood cells called B cells. .....

.... teams from the U.S. Center for disease Control and Prevention (CDC), the World Health Organization, and from other health organizations in Belgium, France, and South Africa. Since July 1, 1995, 233 deaths have been reported among the 293 cases, in Africa (Garrett 195). Since 1976, researchers have searched for an origin and cure of the virus. Scientist have carried out numerous studies and investigations. Therefore, we now know what the virus is capable of doing, how those infected with the disease can be properly treated , and the need to perform prompt action to isolate the virus before it disperses (Garrett 192). The Ebola virus is a member of a .....

.... 3, which was supplying power to cryogenic oxygen tank 2 fans. Within several additional seconds, two other shorted conditions occurred. Electrical shorts in the fan circuit ignited the wire insulation, causing temperature and pressure to increase within cryogenic oxygen tank 2. When pressure reached the cryogenic oxygen tank 2 relief valve full-flow conditions of 1008 psi, the pressure began decreasing for about 9 seconds, at which time the relief valve probably reseated, causing the pressure to rise again momentarily. About a quarter of a second later, a vibration disturbance was noted on the command module accelerometers. The next series o .....

.... able to deliver a greater amount of blood with each stroke as a result of adequate conditioning. Conditioning has other benefits to cardiovascular fitness as well. It will increase oxygenation of the blood due to the fact that while exercising deep breathing increases the blood flow to the lungs. Under a well-planned conditioning program conditioning can help to decrease cholesterol and the incidents of deadly heart disease. Individuals who exercise regularly have a lower rate of heart attacks than individuals who do not participate in an exercise program. One of the most important aspects of conditioning for the heart is the warm-up. Warming-up befo .....

.... Tree (TST), which common in Ethernet environment. The IEEE standard for MAC bridges is ANSI/IEEE 802.1D: MAC Sub-layer Interconnection. Bridge Routing Requirements In general, LANs are low-cost, low-delay, high-bandwidth (e.g., 1-10 Mbps) broadcast channels. A bridged LAN environment preserves the low-delay and high-bandwidth feature but its topology may be more dynamic than in a single LAN due to possible bridge or LAN failures and hosts being moved around. Bridge routing algorithms should meet the following requirements: 1) A bridges LAN environment should resemble a single LAN environment as closely as possible. In other words, the extension should .....

.... careful judgment by physician and patient. is a manifestation of coronary artery disease, the same disease leading to heart attacks. Coronary artery diseas refers to those syndromes caused by blockage to the flow of blood in those arteries supplying the heart muscle itself, i.e., the coronary arteries. Like any other organ, the heart requires a steady flow of oxygen and nutrients to provide energy for rmovement, and to maintain the delicate balance of chemicals which allow for the careful electrical rhythm control of the heart beat. Unlike some other organs, the heart can survive only a matter of minutes without these nutrients, and the rest of the .....

.... from burning fossil fuels rise into the atmosphere and combine with the moisture in the air to form . The main chemicals in air pollution that creates are sulfur dioxide and nitrogen oxides. usually forms high in the clouds where sulfur dioxide and nitrogen oxides react with water, oxygen, and oxidants. This forms a mild solution of sulfuric acid and nitric acid. Sunlight increases the rate of most of these reactions. Rainwater, snow, fog, and other forms of precipitation containing those mild solutions of sulfuric and nitric acids fall to the earth as . Water moves through every living plant and animal, streams, lakes, and oceans in the hyd .....