Aspen Institute. The Aspen Institute is an international nonprofit organization founded in 1950 as the Aspen Institute of Humanistic Studies. The organization is dedicated to fostering enlightened leadership, the appreciation of timeless ideas and values, and open-minded dialogue on contemporary issues.
Nitrogen occurs in all organisms, primarily in amino acids (and thus proteins), in the nucleic acids (DNA and RNA) and in the energy transfer molecule adenosine triphosphate. The human body contains about 3% by mass of nitrogen, the fourth most abundant element in the body after oxygen, carbon, and hydrogen.
The term âsteroidâ is applied to a group of naturally occurring or synthetic fat-soluble organic compounds (lipids), whose structure is chemically based on a steroid nucleus-a hydrogenated cyclopentanoperhydrophenanthrene ring system (seventeen carbon atoms arranged in four rings).