Mydriasis (/máµ»ËdraÉª.ÉsÉªs/) is the dilation of the pupil, usually defined as when having a non-physiological cause, but sometimes defined as potentially being a physiological pupillary response. Non-physiological causes of mydriasis include disease, trauma, or the use of drugs. Normally, as part of the pupillary light reflex, the pupil dilates in the dark and constricts in the light to respectively improve vividity at night and to protect the retina from sunlight damage during the day.
The Cold War Museum. The Strategic Defense Initiative (SDI): Star Wars. The Strategic Defense Initiative (SDI), also known as Star Wars, was a program first initiated on March 23, 1983 under President Ronald Reagan. The intent of this program was to develop a sophisticated anti-ballistic missile system in order to prevent missile attacks from other countries, specifically the Soviet Union.
The Cold War defined the political role of the United States in the postâWorld War II world: by 1989 the US held military alliances with 50 countries, and had 526,000 troops posted abroad in dozens of countries, with 326,000 in Europe and about 130,000 in Asia.