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What is a gluten-free diet?

Gluten is a protein found in wheat, rye and barley. In some genetically predisposed children, food containing gluten causes small-bowl mucusal damage resulting in a disease called gluten-sensitive enteropathy or celiac disease. The treatment is a strict gluten-free diet i.e. elimination of wheat, rye and barley products from the diet. Gluten-free foods are commercially available.

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What is a fish-eye lens?

It is a type of wide-angle lens used in photography to capture extremely wide and hemispherical images. Its focus length varies between 8-10 mm for circular lenses and 15-16 mm for full frame lens. Originally developed for use in meteorology and astronomy, it is used in planetariums and dome theatres to show pictures on a broad canvas.

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What is a fish plate in rail terminology and Greek culture?

In Rail Terminology: A fishplate, splice bar or joint bar is a metal bar that is bolted to the ends of two rails to join them together in a track. The name is derived from fish, a wooden bar with a curved profile used to strengthen a ship’s mast. The top and bottom edges are tapered inwards so the device …

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What is a false vacuum?

False vacuum and true vacuum form a metastable system. Metastable state is a state which does not change with time but is susceptible to falling into lower-energy states with only slight interaction. It is analogous to being at the bottom of a small valley when there is a deeper valley close by. True vacuum is the name applied to a …

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What is a dum dum bullet?

It is an expanding bullet designed to grow on impact, increasing in diameter to limit penetration and/or produce a larger diameter wound. There are many expanding bullet designs though the most commonly encountered are hollow-point bullet and the soft-point bullet. Such bullets are sometimes known as ‘dum dum’ bullets. After an early British example produced in the Dum Dum arsenal, …

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What is a dormant volcano?

There are about 500 active volcanoes around the world, not including those hidden by the sea. A few, such as Stromboli, a volcanic island off the north-eastern coast of Sicily, are active nearly all the time. But most undergo long periods when they are dormant, or sleeping. Some volcanoes stay dormant for so long that they are thought to be …

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What is a digital pet?

A digital pet (also known as a virtual pet or artificial pet) is a type of artificial human companion. They are usually kept for companionship or enjoyment. People may keep a digital pet in lieu of a real pet. Digital pets are distinct in that they have no concrete physical form other than the hardware they run on. Interaction with …

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