.... airscrew, however, belongs to J.P. Paucton, a French mathematician. Paucton envisioned a flying machine that had two airscrews, one for propulsion and the other for sustaining flight. The idea of using an airscrew for propulsion was utilized during the late 1700's to early 1800's. Only after experimentation did the inventors conclude that more propulsive power could be obtained by merely straightening out the surface of the airscrew blades. Attempts to utilize the "straight blade" propeller were made by balloonists. These contraptions were quite strange and hardly fulfilled their purpose of actually propelling the balloon. The basic propeller had evolved .....

.... show a different pattern of behavior and personality. There are, however, certain similarities among ADHD children. ADHD was described as early as 1845 by the German physician Henrich Hoffman in his classic Der Struwelpeter (Slovenly Peter), a collection of humorous moral tales for children. The heroes were taken from his observations of children. In 1902, Dr. G. F. Still, described the behavior of a group of hyperactive children. He knew of no medical reasons for their behavior and made no mention of their educational needs or social skills. He said that part of the problem with ADHD children was "deficient training in the home." In 1923, re .....

.... were made up of cells. This whole idea has been given credit to an English Physicist, Robert Hook (1635-1703), when he looked at a thin slice of cork under powerful hand lens. Hook discovered a large number of cells. Rudolf Virchow (1821-1902) propounded this idea, that the cell is a basic structure and functional unit for all living organisms. A cell can be a wide range of shapes and sizes, although most cells are microscopic. Inside a cell membrane, a nucleus can be seen. The nucleus is the control center of the cell. Between the nucleus and the membrane, there is a polysaccharide matrix called the cytoplasm, where organelles can be found. The or .....

.... advent of freeze fracturing techniques. Nageli and Cramer in 1855 had already suggested that biological cells are separated from their environment by a membrane possessing special characteristics, and in 1900 Overton performed some simple but classical experiments which proposed that cell membranes were composed of lipids (1). By measuring the permeability of various compounds across the membrane of a frog muscle, Overton found some interesting results. He observed that lipophilic molecules (molecules attracted to fat solvents) could easily cross this cell membrane, however larger lipid insoluble molecules could not. He also observed that small polar molecul .....

.... by Antoni van Leeuwenhoek a 1674 Dutch maker of microscopes. Leeuwenhoek born in Delft, Holland and had little or no scientific education. Leeuwenhoek also confirmed the discovery of capillary systems. Theodor Schwann a German physiologist born in Neuss and educated at the universities of Bonn, Wurzburg, and Berlin, Schwann was involved in the study of the structure of plant and animal tissues. Along with Matthias Jakob Schleiden a German botanist, Schwann proposed the cell theory. The cell theory has three parts: 1. All organisms are composed of cells. 2. Cells are the basic units of structure and function in organisms 3. All cells come f .....

.... claiming knowledge that their brains could not have gained through any senses known to science. The first work on ESP was done by the Society for Physical Research in London founded a century ago. Scientists have run thousands of experiments to learn if minds indeed have supernatural powers. Most tests investigated one of the three main "faculties": telepathy, clairvoyance and precognition, collectively called extrasensory perseption (ESP) by American psycologist J.B. Rhine. Dating from the early 1930s, Rhine's tests at Duke University at Durham, North Carolina, remain the most quoted examples of an expirimental blitzkreig on problems of parapsychology. .....

.... with even more researchers and labs having joined in. Most of the labs and researchers are located in France and the United States. The project started in 1990 and was slated to take 15 years and cost $3 billion in U.S. money for the entire project coming to roughly $200 million per year. Federal funding for the project is nearly 60% of the annual need. This has created some funding problems for the project. There also have been technological advances and discoveries that have helped to speed up the project. This automation may help to reduce the cost and help the project to meet its objectives ahead of schedule. The project was estimated to have detaile .....

.... these traits reside on chromosomes. It continuos until 1997 when researchers at Scotland’s Roslin Institute, led by embryologist Lan Wilmut, reported that they cloned a sheep-named Dolly-from the cell of an adult ewe. The next goal of scientists is to sequence all human DNA by 2003, the Human Genome Projects current target date (Lemonick 46). But we should use genetic engineering in a proper way. Our goal should be to find areas where it is needed rather than try to misuse it for personal gain. Genetic engineering can provide medical benefits to humans, but limits have to be set. Our body contains one hundred trillion cells, inside most cells is .....