Depression may be challenging to assess in a patient with dementia. In patients with AD, the presence of depression may range from 6% to 30%, depending on the diagnostic criteria employed (Cummings et al., 1995). The prevalence and course of depression in dementia are controversial, due to several confounding factors.
Astronauts use space shuttles(trasport people and equipment), Space probes (robotic exploration, Spacecrafts (trasport crew, equipment, and other technologies).
U.S. astronaut Bruce McCandless uses a manned maneuvering unit. The Manned Maneuvering Unit (MMU) is an astronaut propulsion unit that was used by NASA on three Space Shuttle missions in 1984. The MMU allowed the astronauts to perform untethered EVA spacewalks at a distance from the shuttle. The MMU was used in practice to retrieve a pair of faulty communications satellites, Westar VI and Palapa B2.