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Hypergravity is defined as the condition where the force of gravity exceeds that on the surface of the Earth. This is expressed as being greater than 1 g. Hypergravity conditions are created on Earth for research on human physiology in aerial combat and space flight, as well as testing of materials and equipment for space missions. Manufacturing of titanium aluminide turbine blades in 20 g is being explored by researchers at the European Space Agency (ESA). All of this is of extreme importance because human physiology and materials are used to build planes, spaceships and structures, which are all accustomed to Earth’s normal gravity. NASA scientists have recently been looking at meteorite impacts, and after testing certain strains of bacteria, they discovered that most strains were able to reproduce under pressures exceeding 7,500 g’s.〔http://www.universetoday.com/89416/hypergravity/〕 Recent research carried out on extremophiles in Japan involved a variety of bacteria including ''Escherichia coli'' and ''Paracoccus denitrificans'' being subject to conditions of extreme gravity. The bacteria were cultivated while being rotated in an ultracentrifuge at high speeds corresponding to 403,627 times "g" (the normal acceleration due to gravity). Another study that has been published in the Proceedings of the National Academy of Sciences, reports that some bacteria can exist even in extreme "hypergravity." In other words, they can still live and breed despite gravitational forces that are 400,000 times greater than what's felt here on Earth. ''Paracoccus denitrificans'' was one of the bacteria which displayed not only survival but also robust cellular growth under these conditions of hyperacceleration which are usually found only in cosmic environments, such as on very massive stars or in the shock waves of supernovas. Analysis showed that the small size of prokaryotic cells is essential for successful growth under hypergravity. The research has implications on the feasibility of existence of exobacteria and panspermia.A concern of this practice is Rapid spinning. If you move your head too quickly while you're inside a fast-moving centrifuge, you might feel uncomfortably like you're tumbling head over heels. This can happen when balance-sensing fluids in the semicircular canals of your inner ear become "confused." Some experiments using centrifuges often include devices that fix the subjects' heads in place, just to prevent that illusion. Traveling through space, however, with your head fixed in place is not practical. In order to understand and describe the influence of gravity in systems, the observation of behaviour in microgravity and at 1g (where g is the gravitational acceleration at the surface of the Earth) is not sufficient.〔http://www.esa.int/esaMI/Education/SEMAEVZRA0G_0.html〕 Researchers calculated from a weight loss experiment that using 5 lb. ankle weights and 2.5 lb. wrist weights would have a 14% improved NEAT calorie burn while doing household chores. Track and basketball primarily plyometric) metrics improved by 8-25% mostly depending upon if the subjects used weighted vests all day or only when training, but the effect disappeared after a month of not using Hypergravity Training. ==Hypergravity effects on the synthesis of materials== High gravity conditions generated by centrifuge is applied in the chemical industry, casting, and material synthesis. The convection and mass transfer are greatly affected by the gravitational condition.Researchers reported that the high-gravity level can effectively affect the phase composition and morphology of the products. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hypergravity」の詳細全文を読む スポンサード リンク
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