Input: Read this: Although dissertations on clothing and its function appear from the 19th century as colonising countries dealt with new environments, concerted scientific research into psycho-social, physiological and other functions of clothing (e.g. protective, cartage) occurred in the first half of the 20th century, with publications such as J. C. Flugel's Psychology of Clothes in 1930, and Newburgh's seminal Physiology of Heat Regulation and The Science of Clothing in 1949. By 1968, the field of environmental physiology had advanced and expanded significantly, but the science of clothing in relation to environmental physiology had changed little. While considerable research has since occurred and the knowledge-base has grown significantly, the main concepts remain unchanged, and indeed Newburgh's book is still cited by contemporary authors, including those attempting to develop thermoregulatory models of clothing development.
Question: What have remained unchanged while the knowledge has grown?

Output: the main concepts

Input: Read this: Today both the Papireto river and the Kemonia are covered up by buildings. However, the shape of the former watercourses can still be recognised today, because the streets that were built on them follow their shapes. Today the only waterway not drained yet is the Oreto river that divides the downtown of the city from the western uptown and the industrial districts. In the basins there were, though, many seasonal torrents that helped formed swampy plains, reclaimed during history; a good example of which can be found in the borough of Mondello.
Question: What follows the former course of the Oreto?

Output: unanswerable

Input: Read this: Atlas, rather than innovate, took a proven route of following popular trends in television and moviesWesterns and war dramas prevailing for a time, drive-in movie monsters another timeand even other comic books, particularly the EC horror line. Atlas also published a plethora of children's and teen humor titles, including Dan DeCarlo's Homer the Happy Ghost (a la Casper the Friendly Ghost) and Homer Hooper (a la Archie Andrews). Atlas unsuccessfully attempted to revive superheroes from late 1953 to mid-1954, with the Human Torch (art by Syd Shores and Dick Ayers, variously), the Sub-Mariner (drawn and most stories written by Bill Everett), and Captain America (writer Stan Lee, artist John Romita Sr.). Atlas did not achieve any breakout hits and, according to Stan Lee, Atlas survived chiefly because it produced work quickly, cheaply, and at a passable quality.
Question: Who ran Atlas?

Output: unanswerable

Input: Read this: The BeiDou Navigation Satellite System (BDS, simplified Chinese: ; traditional Chinese: ; pinyin: Beidou weixing daohang xitong) is a Chinese satellite navigation system. It consists of two separate satellite constellations a limited test system that has been operating since 2000, and a full-scale global navigation system that is currently under construction.
Question: What type of system has been operating since 2010?

Output:
unanswerable