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PubMed. PubMed is a free database including primarily the MEDLINE database of references and abstracts on life sciences and biomedical topics. The United States National Library of Medicine (NLM) at the National Institutes of Health maintains the database as part of the Entrez system of information retrieval.
Isopropyl alcohol ( IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a colorless, flammable organic compound with a pungent alcoholic odor. [9] Isopropyl alcohol, an organic polar molecule, is miscible in water, ethanol, and chloroform, demonstrating its ability to dissolve a wide range of substances including ethyl ...
The Boundary Fire was a 2017 wildfire in Arizona that burned 17,788 acres (7,199 ha) of the Coconino and Kaibab National Forests. The fire was ignited on June 1 when lightning struck a spot on the northeast side of Kendrick Peak within the Coconino National Forest. The fire spread rapidly because of high temperatures, steep terrain, leftovers ...
Structure of a typical L-alpha-amino acid in the "neutral" form Amino acids are organic compounds that contain both amino and carboxylic acid functional groups.[1] Although over 500 amino acids exist in nature, by far the most important are the 22 α-amino acids incorporated into proteins.[2] Only these 22 appear in the genetic code of life.[3 ...
Fibonacci sequence. In mathematics, the Fibonacci sequence is a sequence in which each number is the sum of the two preceding ones. Numbers that are part of the Fibonacci sequence are known as Fibonacci numbers, commonly denoted Fn . The sequence commonly starts from 0 and 1, although some authors start the sequence from 1 and 1 or sometimes ...
Cats are common pets throughout the world, and their worldwide population as of 2007 exceeded 500 million. [199] As of 2017, the domestic cat was the second most popular pet in the United States, with 95.6 million cats owned [200] [201] and around 42 million households owning at least one cat. [202]
where x represents an unknown value, and a, b, and c represent known numbers, where a ≠ 0. (If a = 0 and b ≠ 0 then the equation is linear, not quadratic.)The numbers a, b, and c are the coefficients of the equation and may be distinguished by respectively calling them, the quadratic coefficient, the linear coefficient and the constant coefficient or free term.
