Prognostic markers are useful to stratify the patients into groups, guiding towards precise medicine discovery. Seeds may require three months of cold to stratify. Under the Russian Empire, Polish society tended to stratify. It is used to stratify responsibility in most training programs and to determine salary. This provides a clear evidence base on which to stratify (group) related patients. This will stratify the crushed aggregate by density making separation easier. This effort was the first by any medical specialty to stratify risk. Because of its small size, Keswick Reservoir does not stratify. They swim in large schools that stratify by size and age along the coast. The acquired businesses of LiveVault and Stratify Inc. were consolidated into Iron Mountain Digital. Some South Asian Muslims have been known to stratify their society according to "qaums". Some South Asian Muslims have been known to stratify their society according to "quoms". The lower, middle, and upper floors of the building gradually stratify into distinct groups. Once mixed, gas will not stratify with time.