Siliceous plankton have been an important component of the oceanic silica cycle since the evolution of Radiolaria during late Precambrian or early Paleozoic time. Diatoms did not enter the cycle until Jurassic time, but ...

The effects of dislocations and impurities on the macroscopic elastic properties of smectic‐A liquid crystals are discussed. The first conclusion is that smectics behave like linear elastic media only so long as the stresses ...

This paper describes part of the discourse component of a speech understanding system for task-oriented dialogs, specifically, a mechanism for establishing a focus of attention to aid in identifying the referents of definite ...

Silicified dolomite of the approximately one billion year old Skillogalee Dolomite of the Adelaide Geosyncline, South Australia, contains organically preserved microfossils of a structurally complex, crustose pleurocapsalean ...