|
|
A cataract is a clouding of the eyes' natural lens. As we age, some clouding of the lens may occur. The first sign of a cataract is usually blurry vision. Although glasses and other visual aids may at first help a person with cataracts, surgery may become inevitable. Cataract surgery is very successful in restoring vision, and it is the most frequently performed surgery in the United States.
Approximately one in three babies in the United States is now delivered by cesarean section. The number of cesarean sections in the United States has risen 46% since 1996.
Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
There can actually be a 25-hour time difference between certain locations in the world. The International Date Line passes between the islands of Samoa and American Samoa. It is not a straight line, but "zig-zags" around various island chains. Therefore, Samoa and nearby islands have one date, while American Samoa and nearby islands are one day behind. Daylight saving time is used in some islands, but not in others—further shifting the hours out of sync with natural time.
About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
![Surface magnetic field of SU Aur (a young star of T Tauri type), reconstructed by means of Zeeman-Do](https://biology-forums.com/gallery/47/medium_12359_16_06_12_7_20_16.jpeg)
![(Left panel) The transition level (TL) for moving out of the parental home for 240 young men and ...](https://biology-forums.com/gallery/47/medium_660365_23_12_16_3_52_07_243661518.jpeg)