Post-mortem intervalThe post-mortem interval (PMI) is the time that has elapsed since an individual's death. When the time of death is not known, the interval may be estimated, and so an approximate time of death established. Postmortem interval estimations can range from hours, to days or even years depending on the type of evidence present. There are standard medical and scientific techniques supporting such an estimation. Changes to a body occurring after death (post-mortem changes) include: Algor mortis: body cooling; Livor mortis: settling of blood in the lowest-placed parts of the body; Rigor mortis: stiffening of limbs.
TaigaTaiga (ˈtaɪɡə; тайга́; relates to Mongolic or Turkic languages), generally referred to in North America as a boreal forest or snow forest, is a biome characterized by coniferous forests consisting mostly of pines, spruces, and larches. The taiga or boreal forest has been called the world's largest land biome. In North America, it covers most of inland Canada, Alaska, and parts of the northern contiguous United States.
Biosafety levelA biosafety level (BSL), or pathogen/protection level, is a set of biocontainment precautions required to isolate dangerous biological agents in an enclosed laboratory facility. The levels of containment range from the lowest biosafety level 1 (BSL-1) to the highest at level 4 (BSL-4). In the United States, the Centers for Disease Control and Prevention (CDC) have specified these levels in a publication referred to as BMBL. In the European Union, the same biosafety levels are defined in a directive.
Unit of timeA unit of time is any particular time interval, used as a standard way of measuring or expressing duration. The base unit of time in the International System of Units (SI), and by extension most of the Western world, is the second, defined as about 9 billion oscillations of the caesium atom. The exact modern SI definition is "[The second] is defined by taking the fixed numerical value of the cesium frequency, ΔνCs, the unperturbed ground-state hyperfine transition frequency of the cesium 133 atom, to be 9 192 631 770 when expressed in the unit Hz, which is equal to s−1.
