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).
Key Discoveries. Deep Space 1 was the first spacecraft to use an ion engine. Its successful missions to asteroid 9969 Braille and comet Borrelly using the revolutionary technology heralded a new age of ion-propelled spacecraft, such as NASA's Dawn, built for tricky flights to elusive space objects like comets and asteroids.