Copper is a chemical element with the symbol Cu (from cuprum) and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; a freshly exposed surface has a reddish-orange color. It is used as a conductor of heat and electricity, a building material, and a constituent of various metal .
A typewriter is a mechanical or electromechanical machine for writing in characters similar to those produced by printer's movable type by means of keyboard-operated types striking a ribbon to transfer ink or carbon impressions onto the paper. Typically one character is printed per keypress. The machine prints characters by making ink impressions of type elements similar to the sorts used in movable typeletterpress printing.
A stroke, sometimes referred to as a cerebrovascular accident ( CVA), is the rapid loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia (lack of blood flow) caused by blockage (thrombosis, arterial embolism), or a hemorrhage. As a result, the affected area of the brain cannot function, which might result in an inability to move one or more limbs on one side of the body, inability to understand or formulate speech, or an inability to see one side of the vi..
History (from Greek ἱστορία, historia, meaning "inquiry, knowledge acquired by investigation") is the study of the past, specifically how it relates to humans. It is an umbrella term that relates to past events as well as the discovery, collection, organization, and presentation of information about these events. The term includes cosmic, geologic, and organic history, but is often generically implied to mean human history. Scholars who write about history are called . Events occurring prior to wr..
Carbapenem-resistant enterobacteriaceae ( CRE) or Carbapenemase-producing Enterobacteriaceae (CPE), are gram-negative bacteria that are nearly resistant to the carbapenem class of antibiotics, considered the "drug of last resort" for such infections. Enterobacteriaceae are common commensals and infectious agents. Experts fear CRE as the new "superbug". The bacteria can kill up to half of patients who get bloodstream infections. Tom Frieden, head of the Centers for Disease Control has referred to CRE as "n..
A symbol is an object or a concept that represents, stands for or suggests another idea, visual image, belief, action or material entity. Symbols take the form of words, sounds, gestures, ideas or visual images and are used to convey other ideas and beliefs. For example, a red octagon may be a symbol for "STOP". On a map, a blue line might represent a river. Numerals are symbols for . letters may be symbols for sounds. Personal names are symbols representing individuals. A red rose may symbolize love and..
