Loik M. E., Nobel P. S., Water relations and mucopolysaccharide increases for a winter hardy cactus during acclimation to subzero temperatures, Oecologia, 1991, 88(3):340-346, doi: 10.1007/BF00317576
The experiment involves seven weeks of acclimation of material identified as Opuntia humifusa from Bald Knob in Virginia. The analysis distinguishes the concentration of solutes through water loss from an increase in osmotically active substances. It also considers the role of mucilage.