... hypertension. One is primary hypertension and the other is secondary hypertension. The cause of primary hypertension is unknown. It just happens but however, there are certain risk factors or associations such as hereditary factors, race, age, environmental and life-style factors (where you live, salt and other chemicals, weight, stress, alcohol, lack of exercise). The difference between primary and secondary hypertension is that we know the causes of secondary hypertension. Usually, the causes of secondary hypertension include renal artery stenosis (or other cause of increased plasma renin), renal parenchym ...

... He began persuing alpha particles in 1908. With the help of Geiger he found the number of alpha particles emitted per second by a gram of radium. He was also able to confirm that alpha particles cause a faint but discrete flash when striking luminescent zinc sulfide screen. These great accomplishments are all overshadowed by Rutherford's famous Gold Foil experiment which revolutionized the atomic model. This experiment was Rutherford's most notable achievement. It not only disproved Thomson's atomic model but also paved the way for such discoveries as the atomic bomb and nuclear power. The atomic model h ...

... extra terrestrials. (60 minutes, CBS) On the contrary, most scientists now agree that almost all sightings and stories of extra terrestrials are not authentic. The United States government has records of thousands of UFO sightings since 1948, including photos of alleged UFOs and interviews with people who claim to have seen them. Since UFOs were considered a potential security risk, the report on these sightings was originally classified as secret. (Craig, 917) When the report was later declassified it showed that 90 percent of all UFO sightings could be easily explained. Most of the sightings turned out to be ...

... of the star, all the way down to El Nath, the second brightest star (gamma Auriga) which is actually shared with Taurus, and also known as beta Taurus. Auriga's stars are fairly bright; five are second magnitude or brighter. Alpha Auriga (Capella) is the sixth brightness star, at a visual magnitude of 0.08. The star is 43.5 light years away, and is about ten times the size of our Sun. Capella's visual magnitude is really the combined brightness of the primary star and another star that revolves every 104 days. This star is also known as Menkalina. The star name derives from the Arabic name Al Mankib d ...

... are manufactured many chemicals are used to create it. However because of the difficulty and cost of properly disposing of these products they are often emitted into the atmosphere with little or no treatment. The term was first considered to be important about 20 years ago when scientists in Sweden and Norway first believed that acidic rain may be causing great ecological damage to the planet. The problem was that by the time that the scientist found the problem it was already very large. Detecting an acid lake is often quite difficult. A lake does not become acid over night. It happens over a period of ...

... of years ago. Burning fossil fuels has other downfalls, too. All the burning that is required to turn the turbines releases much sulfur, nitrogen gases, and other pollutants into the atmosphere. The cleanest, cheapest, and least polluting power plant of the two types is the hydroelectric power plant. The main reason most countries use thermal versus the hydroelectric is because their countries don’t have enough concentrated water to create enough energy to generate electricity. (World Book vol. 14, 586) Nuclear power plants generate only about eleven percent of the world’s electricit ...

... are over the ocean in either the North Atlantic ocean, or the eastern North Pacific Ocean. If a hurricane is in the western Pacific Ocean than it is called a typhoon. One in the Indian Ocean is called a cyclone. The danger region of a hurricane is normally in the Gulf of Mexico or the Atlantic Ocean. The hurricane season is the six month time period from June-November. The peak month of hurricanes is September. Hurricanes form over the ocean. Easterly waves, what hurricanes develop from, are long, narrow regions of low pressure which occur in ocean winds called trade winds. At first, these easterly waves can grow ...

... BACKGROUND Use of Animals in Research Some of the earliest recorded studies involving animals were performed by Aristotle (384-322 B.C.), who revealed anatomical differences among animals by dissecting them (Rowan, 1984). The Greek physician Galen (A.D. 129-199) maintained that experimentation led to scientific progress and is said to have been the first to conduct demonstrations with live animals--specifically pigs-a practice later extended to other species and termed "vivisection" (Loew, 1982). However, it was not until the sixteenth century that many experiments on animals began to be recorded. In 1628, William ...

... of what the virus is capable of doing, how victims can be properly treated , and by performing prompt action to isolate the virus before it has dispersed. The virus is a member of a family of RNA viruses know as filoviruses. Marburg virus and four viruses: Zaire, Sudan, Reston and Tai are the five different viruses that have been known to cause disease in humans, while Reston only causes disease within monkeys. Filoviruses, arenaviruses, flaviruses, and bunyaviruses are the viruses responsible for causing viral hemorrhagic fevers. All forms of virus of viral hemorrhagic fever begin with fever and muscle ach ...

... do know, however, that Mars is relatively small and that changes take place in the surface features when the seasons change. It is also known that dust storms are prevalent and leaves the surface of Mars covered by a red haze. Mars has a very thin atmosphere which is composed of carbon dioxide, nitrogen, argon, water vapor and oxygen. Mars also has no magnetic field. " Because the atmosphere of mars is so thin, wind velocities up to several hundred Km per hour are required to raise the dust particles during a dust storm, and these fast- moving particles erode structures with a sand-blasting effect " (Grolier, 1 ...