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In a large, blinded, randomized trial involving critically ill adults, no significant difference in 90-day mortality was noted between those who received red cells stored for a mean of 11.8 days and those who received red cells stored for a mean of 22.4 days.

The idea that geological maps have an inherent and inviolable internal logic that is entirely distinct from their interpretation and, that this logic is based on fundamental principles of spatial and temporal field relations, is central to the development of a theory of spatio-temporal relations for geoscience. This paper examines the conceptual basis for such a theory; investigates ways in which it may be formalized; and provides suggestions for its implementation within the context of geoscience spatial information systems. The design, implementation, and benefits of a prototype reasoning system--the scSPATIO- scCHRONOLOGICAL REASONER--is described. The reasoner makes use of an elegant interval-based temporal logic that effectively captures the temporal hierarchy of geologic data, as well as a reasoning algorithm based on constraint propagation. Examples are provided to show a variety of straightforward and essential, yet previously impossible tasks, that can be accomplished within the framework of the reasoner.