Arsenic is present in the environment as a naturally occurring substance or as a result of contamination from human activity. It is found in water, air, food, and soil in organic and inorganic forms.
Latent Semantic Analysis (LSA), sometimes referred to as Latent Semantic Indexing (LSI), is an information modeling and analysis technology. It enables you to organize and examine large collections of information based on meaning (semantics), not just matching the words or items being used.
Lysergic acid diethylamide, known as LSD, is one of the most powerful hallucinogens out there. It is a drug of extreme unpredictability, and is banned for use in the United States, even though it was once used as a psychiatric drug, and has been used in secret government tests.