level preserving
41Modular group — For a group whose lattice of subgroups is modular see Iwasawa group. In mathematics, the modular group Γ is a fundamental object of study in number theory, geometry, algebra, and many other areas of advanced mathematics. The modular group can be… …
42Oral history preservation — is the field that deals with the care and upkeep of oral history materials, whatever format they may be in. Oral history is a method of historical documentation, using interviews with living survivors of the time being investigated. Oral history… …
43performing arts — arts or skills that require public performance, as acting, singing, or dancing. [1945 50] * * * ▪ 2009 Introduction Music Classical. The last vestiges of the Cold War seemed to thaw for a moment on Feb. 26, 2008, when the unfamiliar strains …
44Switzerland — /swit seuhr leuhnd/, n. a republic in central Europe. 7,248,984; 15,944 sq. mi. (41,294 sq. km). Cap.: Bern. French, Suisse. German, Schweiz. Italian, Svizzera. Latin, Helvetia. * * * Switzerland Introduction Switzerland Background: Switzerland s …
45First aid — This article is about the provision of immediate care. For the Transformers character, see First Aid (Transformers) …
46Wood preservation — All measures that are taken to ensure a long life of wood fall under the definition wood preservation (timber treatment). Apart from structural wood preservation measures, there are a number of different (chemical) preservatives and processes… …
47library — /luy brer ee, breuh ree, bree/, n., pl. libraries. 1. a place set apart to contain books, periodicals, and other material for reading, viewing, listening, study, or reference, as a room, set of rooms, or building where books may be read or… …
48Christianity — /kris chee an i tee/, n., pl. Christianities. 1. the Christian religion, including the Catholic, Protestant, and Eastern Orthodox churches. 2. Christian beliefs or practices; Christian quality or character: Christianity mixed with pagan elements; …
49nutrition, human — Introduction process by which substances in food are transformed into body tissues and provide energy for the full range of physical and mental activities that make up human life. The study of human nutrition is interdisciplinary in… …
50Category theory — In mathematics, category theory deals in an abstract way with mathematical structures and relationships between them: it abstracts from sets and functions to objects and morphisms . Categories now appear in most branches of mathematics and in… …
