Only in the extract containing the radioactively labeled phenylalanine, was the resulting protein also radioactive. Measurements of internal fluxes is possible using radioactively labelled or NMR visible metabolites. Enzyme assays are commonly done using fluorometric detection or older radioactively labeled substrates. The quantity of these antibodies is determined by using radioactively labelled dsDNA. The ddNTPs may be radioactively or fluorescently labelled for detection in DNA sequencers. The ddNTPs may be radioactively or fluorescently labelled for detection in automated sequencing machines. Briefly, pulse-chase assays allow researchers to track radioactively labelled molecules in the cell. Later, techniques were developed to substitute radioactively labeled microspheres for fluorescent microspheres. In most reactors it also contains the radioactively contaminated systems. The Na@C then decays radioactively to Ne@C, without any other neon isotopes. PPX activity is quantified by measuring the loss of radioactively labeled P polyphosphate. The facility was used to store a wide variety of radioactively contaminated items. On 11 January 2012, radioactively contaminated water was found in two tunnels. He also discovered that some isomers do not change into other elements on decaying radioactively. All of these elements are unstable and decay radioactively into other elements.