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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 ...
Definitions Generation and parameters Let be a standard normal variable, and let and be two real numbers, with >.Then, the distribution of the random variable = + is called the log-normal distribution with parameters and .These are the expected value (or mean) and standard deviation of the variable's natural logarithm, not the expectation and standard deviation of itself.
Probability theory. In probability theory and statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable. The general form of its probability density function is. The parameter is the mean or expectation of the distribution (and also its median and mode ), while ...
Blue light is scattered more than other wavelengths by the gases in the atmosphere, surrounding Earth in a visibly blue layer at the stratosphere, above the clouds of the troposphere, when seen from space on board the ISS at an altitude of 335 km (208 mi) (the Moon is visible as a crescent in the far background).[1] The atmosphere of Earth is ...
Quantum mechanics is a fundamental theory in physics that describes the behavior of nature at and below the scale of atoms. [2] : 1.1 It is the foundation of all quantum physics, which includes quantum chemistry, quantum field theory, quantum technology, and quantum information science . Quantum mechanics can describe many systems that ...
In 1798, commander Franz Alois Pfyffer von Altishofen went into exile with the deposed Pius VI. After the death of the Pope on 29 August 1799, the Swiss Guard was disbanded and then reinstated by Pius VII in 1800. In 1809, Rome was again captured by the French and the guard was again disbanded. [2]
The earliest datable record of an aurora was recorded in the Bamboo Annals, a historical chronicle of the history of ancient China, in 977 or 957 BC. An aurora was described by the Greek explorer Pytheas in the 4th century BC. Seneca wrote about auroras in the first book of his Naturales Quaestiones, classifying them, for instance, as pithaei ('barrel-like'); chasmata ('chasm'); pogoniae ...
