Contradictions of slate formation resolved?
Article Abstract:
Electron microscopy and X-ray research on slates from various environments has led to the development of a model for slate cleavage. This model concentrates on the respective roles of phyllosilicates of depositional origin and those created during diagensis and metamorphism. The model seems to indicate that the roles of thermal and strain energy cannot be distinguished during cleavage formation. Mechanical work requires less energy than chemical work, as indicated by the preference of mechanical processes in low-grade and low-strain regions.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1998
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Ribozyme crevices and catalysis
Article Abstract:
A structure of the ribozyme from the hepatitis delta helper virus (HDV) and a 5-A structure of the group I intron from Tetrahymena thermophila have been identified. The RNAs look like enzymes, with active sites organized and located in crevices. However they differ from each other in that the HDV ribozyme is around one-fifth the size of the Tetrahymena ribozyme. The new structures enable evaluation of what works in structural prediction and what does not work, and why.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1998
User Contributions:
Comment about this article or add new information about this topic:
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