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This is a list of radioactive nuclides (sometimes also called isotopes), ordered by half-life from shortest to longest, in seconds, minutes, hours, days and years. Current methods make it difficult to measure half-lives between approximately 10 −19 and 10 −10 seconds. [1]
Half-life (symbol t ½) is the time required for a quantity (of substance) to reduce to half of its initial value.The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable atoms survive.
The protein MCL1 has a very short biological half-life of only 20–30 minutes. [8] The loss of MCL1 has a more dramatic impact than the loss of any other anti-apoptotic member of the Bcl-2 family. Loss of the Mcl-1 gene results in embryo death when the embryo is only around 3.5 days old, before it has even implanted.
In addition, there are 34 known synthetic radioisotopes, the most stable of which is 182 Hf with a half-life of 8.9 × 10 6 years. This extinct radionuclide is used in hafnium–tungsten dating to study the chronology of planetary differentiation. [5] No other radioisotope has a half-life over 1.87 years. Most isotopes have half-lives under 1 ...
Considering all decay modes, various models indicate a shift of the center of the island (i.e., the longest-living nuclide) from 298 Fl to a lower atomic number, and competition between alpha decay and spontaneous fission in these nuclides; [83] these include 100-year half-lives for 291 Cn and 293 Cn, [55] [78] a 1000-year half-life for 296 Cn ...
Erythropoietin (/ ɪ ˌ r ɪ θ r oʊ ˈ p ɔɪ. ɪ t ɪ n,-r ə-,-p ɔɪ ˈ ɛ t ɪ n,-ˈ iː t ɪ n /; [1] [2] [3] EPO), also known as erythropoetin, haematopoietin, or haemopoietin, is a glycoprotein cytokine secreted mainly by the kidneys in response to cellular hypoxia; it stimulates red blood cell production (erythropoiesis) in the bone marrow.
Neural progenitors (green) in olfactory bulb with astrocytes (blue). Example of the pattern of division of a progenitor cell (PC) which results in the production of an intermediate progenitor cell (IPC). Both cells later produce one or two neural cells (N). A progenitor cell is a biological cell that can differentiate into a specific cell type.
Forty-one radioisotopes have been characterized, with the most stable being 145 Pm with a half-life of 17.7 years, 146 Pm with a half-life of 5.53 years, and 147 Pm with a half-life of 2.6234 years. All of the remaining radioactive isotopes have half-lives that are less than 365 days, and the majority of these have half-lives that are less than ...