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hearing aid

(Encyclopedia)hearing aid, device used in some forms of deafness to amplify sound before it reaches the auditory organs. Modern hearing aids are electronic. They contain a tiny receiver and a transistor amplifier, ...

acquired immunodeficiency syndrome

(Encyclopedia)acquired immunodeficiency syndrome: see AIDS. ...

tattoo

(Encyclopedia)tattoo, the marking of the skin with punctures into which pigment is rubbed. The word originates from the Tahitian tattau [to mark]. The term is sometimes extended to scarification, which consists of ...

HIV

(Encyclopedia)HIV, human immunodeficiency virus, either of two closely related retroviruses that invade T-helper lymphocytes and are responsible for AIDS. There are two types of HIV: HIV-1 and HIV-2. HIV-1 is respo...

Holzer, Jenny

(Encyclopedia)Holzer, Jenny, 1950–, American artist, b. Gallipolis, Ohio. She links text and image in works of art composed of short aphorisms or longer declarations. Influenced by Dada, conceptual art, and femin...

tree surgery

(Encyclopedia)tree surgery, practice of repairing damaged trees to restore their appearance and to arrest disease. Injured or diseased parts are first removed (even small cavities in the bark may harbor injurious f...

retrovirus

(Encyclopedia)retrovirus, type of RNA virus that, unlike other RNA viruses, reproduces by transcribing itself into DNA. An enzyme called reverse transcriptase allows a retrovirus's RNA to act as the template for th...

Kramer, Larry

(Encyclopedia)Kramer, Larry (Lawrence David), 1935-2020 American gay-rights activist and playwright, b. Bridgeport, Ct., Yale Univ. (B.A., 1957). After graduating co...

Louganis, Greg E.

(Encyclopedia)Louganis, Greg E. lo͞ogāˈnĭs [key], 1960–, American diver, b. San Diego, Calif. He won gold medals in springboard diving and platform diving in the 1984 Olympics and repeated in both categories ...

McNally, Terrence

(Encyclopedia)McNally, Terrence, 1939–2020, American playwright, b. St. Petersburg, Fla., grad. Columbia, 1960. Known for his dark humor, social satire, and focus on human isolation and the need to connect, he of...