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PTAL Grid Comparison 18Feb19 V3
PTAL may refer to: * Public transport accessibility level The public transport accessibility level (PTAL) is a method sometimes used in United Kingdom transport planning to assess the access level of geographical areas to public transport. PTAL is a simple, easily calculated approach that hinges on th ..., a method sometimes used in UK transport planning to assess the access level of geographical areas to public transport * Phenylalanine/tyrosine ammonia-lyase, an enzyme * Postgraduate Training Authorization Letter {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Public Transport Accessibility Level
The public transport accessibility level (PTAL) is a method sometimes used in United Kingdom transport planning to assess the access level of geographical areas to public transport. PTAL is a simple, easily calculated approach that hinges on the distance from any point to the nearest public transport stop, and service frequency at those stops. The result is a grade from 1–6 (including sub-divisions 1a, 1b, 6a and 6b), where a PTAL of 1a indicates extremely poor access to the location by public transport, and a PTAL of 6b indicates excellent access by public transport. Background The PTAL calculation was originally developed by the Borough of Hammersmith and Fulham in 1992, and was later adopted by Transport for London in 2004 as the standard method for calculation of public transport access in London. It is not commonly used outside Greater London or the south east of England. Method The first stage in PTAL calculation is to calculate the walking distance from the site ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylalanine/tyrosine Ammonia-lyase
Phenylalanine/tyrosine ammonia-lyase (EC 4.3.1.25, PTAL, bifunctional PAL) is an enzyme with systematic name L-phenylalanine(or L-tyrosine):''trans''-cinnamate(or ''trans-p''-hydroxycinnamate) ammonia-lyase. This enzyme catalyses the following chemical reaction : (1) L-phenylalanine \rightleftharpoons ''trans''-cinnamate + NH3 : (2) L- tyrosine -Tyrosine or tyrosine (symbol Tyr or Y) or 4-hydroxyphenylalanine is one of the 20 standard amino acids that are used by cells to synthesize proteins. It is a non-essential amino acid with a polar side group. The word "tyrosine" is from the Gr ... \rightleftharpoons ''trans-p''-hydroxycinnamate + NH3 This enzyme is a member of the aromatic amino acid lyase family. References External links * {{DEFAULTSORT:Phenylalanine tyrosine ammonia-lyase EC 4.3.1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
