abbreviation: Marine Corps Base
Molecular and Cellular Biology [periodical, périodique]
Miniature circuit breaker, these are the switches (or fuses) protecting each circuit.
Memory Control Block
Miniature Circuit Breaker - Modern replacement for fuses in consumer units (fuse boxes). Has benefit of more precise tripping and can be reset. In my opinion all fuse boxes and consumer units that still have fuses should be converted to use these.