Sulfur exists in two allotropic forms. Allotropes are forms of an element with different physical and chemical properties. The two forms of sulfur are known as Î±-form and Î²-form (the Greek letters alpha and beta, respectively).
National Organizations American Psychological Association (APA) The American Psychological Association (APA) is located in Washington, D.C., and is the largest scientific and professional organization representing psychology in the United States. APA was founded at the turn of the 20th century, and is the world's largest association of psychologists. APA - Division 16 - Division of School Psychology
Seligman was elected President of the American Psychological Association for 1998. He is the founding editor-in-chief of Prevention and Treatment Magazine (the APA electronic journal) and is on the board of advisers of Parents magazine. Review of General Psychology survey, published in 2002, ranked Seligman as the 31st most cited psychologist of the 20th century. Seligman is controversial in the psychology field because his studies have been used repeatedly by the US Army as the cornerstone of their torture practices in Iraq.