Scientists of tomorrow

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Howard Owens, of Northwestern High School in Prince Georges County, MD, briefly discusses the purpose of the National Science Fair. Talented students then display and explain their Science Fair projects. Don Boyle experiments with the effects of radio waves on seed germination. Mary Catherine White reconstructs a functioning battery using Volta's methods. Gary Miggs creates a diorama based on the fossils characteristic of the Devonian Period. Jean Spencer determines the amount of black widow spider venom required to kill a white mouse. Fred Shindler researches the life cycle of the corn borer in an unsuccessful attempt to break that cycle and thus eradicate the pest.

Seeing is not believing

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The brain perceives not only what is seen by the eyes, but also processes experience and expectations to sometimes perceive not exactly what was seen. Magic tricks depend on the perception of the eye. Optical illusions and moving picture frames show that the eye can be tricked. The ability to detect movement is relative, but eyes can determine distance by working together.

Why do your muscles get tired?

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There are 234 muscles in the human body which interpret signals from the nervous system to perform simple and complex operations. Pairs of muscles often work together by expanding and contracting in opposition to each other to perform at optimum efficiency. Muscle contraction consists of physical, chemical, and electrical changes.

Sound and hearing

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Determining the levels of hearing loss in young children can be measured by noting the child's reactions to various levels of volume and pitch. The key to treating hearing impairments in children is the early detection of hearing loss. Training parents to work with deaf children and the early fitting of hearing aids is important in the development of communication skills.

Man will conquer space: part two

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In this second in a series of programs on space exploration, Francis Clauser discusses how Newton's third law explains the propulsion of rocket ships. Speeds of over 25,000 miles per hour are needed to escape the earth's atmosphere and 16,000 miles per hour to put a rocket in orbit around the earth. Fuels that can be used to propel rockets include hydrazine and nitric acid. A model of a three stage rocket is shown to demonstrate how man will begin space travel.

Blowing glass for science

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Scientific research often requires specially made equipment. The glass blower can make intricate apparatuses designed to exacting specifications that are used in scientific laboratories for specific research purposes. Master glass blower John Lehman demonstrates this by making a hydrogenation apparatus that can turn vegetable oils into solid shortening. The first cathode ray tubes used in early television were created by glass blowers.

Stars in your skies

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The program begins with a discussion of the solar system with the sun in the center and the nine planets, with their satellites or moons. Comets also travel around the sun in very irregular orbits. Great clusters of billions of stars form galaxies. The earth is near the center of the galaxy known as the Milky Way. Stars are arranged into the constellations that have distinctive configurations.

The worm turns

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The life cycle of the butterfly goes through metamorphosis by changing from eggs to larvae to caterpillars to pupae to butterflies. Various species of butterflies and their anatomy, variety, and migration are discussed along with the fact that many cultures around the world eat butterflies and caterpillars.

Don't drink that water

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Telegrams from educators and scholars mark the third anniversary of the Johns Hopkins Science Review. Dr. Abel Wolman summarizes the history of methods of acquiring pure water and the science of sanitary engineering. Chlorine was discovered to be a reliable and practical chemical to use to kill water-borne bacteria. Dr. Wolman also shows a film of microscopic organisms and silt in water and discusses the decline of typhoid fever. Dr. Wolman and his colleagues use both animated films and models of a water filtration plant and a sewage treatment plant to explain the water purification processes.

Can we predict elections?

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Most pollsters incorrectly predicted the 1948 United States presidential election. Political scientists try to determine political trends in the U.S. by tracking the party affiliation of the House of Representatives. Local and regional differences can be seen by analyzing election results over the years. Most states show trends that mirror overall national results. Analysis of these factors can help predict future elections.