With more education and experience, accountants can become certified. Some financial documents, such as those submitted to the Securities and Exchange Commission, must be signed by a Certified Public Accountant.
Hyperchromicity is the increase of absorbance (optical density) of a material. The most famous example is the hyperchromicity of DNA that occurs when the DNA duplex is denatured. The UV absorption is increased when the two single DNA strands are being separated, either by heat or by addition of denaturant or by increasing the pH level.
- 35 - DNA in the laboratory, most notably in the polymerase chain reaction (PCR). The temperature at which half of a sample of DNA molecules has denatured is referred to as the T m (melting temperature) for that sample. It depends upon the salt concentration (the higher the salt concentration the higher the T m).