Elongation factor

Elongation factors are a set of proteins that are used in protein synthesis in the process of cell cycle and elongation in some cells. In the ribosome, they facilitate translational elongation, from the formation of the first peptide bond to the formation of the last one.

Elongation is the most rapid step in translation:

Elongation factors play a role in orchestrating the events of this process, and in ensuring the 99.99% accuracy of translation at this speed.

Elongation factors are also a target for pathogen toxins. Corynebacterium diphtheriae produces the diphtheria toxin that alters protein function in the host by inactivating elongation factor (EF-2). This causes pharyngitis and pseudomembranous inflammation in the throat.

Pseudomonas aeruginosa's exotoxin A also inhibits EF-2.

See also

Enhanced Fujita scale

The Enhanced Fujita scale (EF-Scale) rates the strength of tornadoes in the United States and Canada based on the damage they cause.

Implemented in place of the Fujita scale introduced in 1971 by Tetsuya Theodore Fujita, it began operational use in the United States on February 1, 2007, followed by Canada on April 1, 2013. The scale has the same basic design as the original Fujita scale—six categories from zero to five, representing increasing degrees of damage. It was revised to reflect better examinations of tornado damage surveys, so as to align wind speeds more closely with associated storm damage. Better standardizing and elucidating what was previously subjective and ambiguous, it also adds more types of structures and vegetation, expands degrees of damage, and better accounts for variables such as differences in construction quality.

The new scale was publicly unveiled by the National Weather Service at a conference of the American Meteorological Society in Atlanta on February 2, 2006. It was developed from 2000 to 2004 by the Fujita Scale Enhancement Project of the Wind Science and Engineering Research Center at Texas Tech University, which brought together dozens of expert meteorologists and civil engineers in addition to its own resources.