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).
Dawn is not the first NASA spacecraft to use ion propulsion. The agency's Deep Space 1 spacecraft, launched in 1998 to test new technologies and capture data about a comet, was the first to use an alternative to traditional propulsion. The Dawn spacecraft, however, has used ion propulsion to travel much farther and to study two extraterrestrial objects.