Given a text passage, come up with an appropriate title for it. The title should accurately represent what the main focus of the passage is. The title of a passage may be present in the first few sentences of the passage and/or be referred to multiple times in the passage. The title should be 1-5 words long.

Q: `` Tropical '' refers to the geographical origin of these systems , which form almost exclusively over tropical seas . `` Cyclone '' refers to their winds moving in a circle , whirling round their central clear eye , with their winds blowing counterclockwise in the Northern Hemisphere and blowing clockwise in the Southern Hemisphere . The opposite direction of circulation is due to the Coriolis effect . Tropical cyclones typically form over large bodies of relatively warm water . They derive their energy through the evaporation of water from the ocean surface , which ultimately recondenses into clouds and rain when moist air rises and cools to saturation . This energy source differs from that of mid-latitude cyclonic storms , such as nor'easters and European windstorms , which are fueled primarily by horizontal temperature contrasts . Tropical cyclones are typically between 100 and 2,000 km ( 62 and 1,243 mi ) in diameter .

A: Tropical cyclone
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Q: Hospital emergency codes have often varied widely by location , even between hospitals in the same community . Confusion over these codes has led to the proposal for and sometimes adoption of standardized codes . In many American , Canadian , New Zealand and Australian hospitals , for example `` code blue '' indicates a patient has entered cardiac arrest , while `` code red '' indicates that a fire has broken out somewhere in the hospital facility .

A: Hospital emergency codes
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Q: Castle Clinton or Fort Clinton , previously known as Castle Garden , is a circular sandstone fort now located in Battery Park , in Manhattan , New York City . It is perhaps best remembered as America 's first immigration station ( predating Ellis Island ) , where more than 8 million people arrived in the U.S. from 1855 to 1890 . Over its active life , it has also functioned as a beer garden , exhibition hall , theater , and public aquarium , and currently is a national monument .

A:
Castle Clinton
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