Abstract: Systems and methods are provided for capturing a complete baseline image of the operating environment of a host computer system on an external storage device and for generating incremental backups of the operating environment as changes to the operating environment are identified to create an aggregate baseline image of the operating environment of the host computer system. The external storage device can be disconnected from the host computer system and connected to a remote host where the aggregate baseline image can be used launch a remote host environment on a virtual machine running on the remote host. The remote host environment allows a user to make changes to the remote host environment and the changes can be written back to external storage device as a delta image that is included in the aggregate baseline image. The aggregate baseline image can then be synchronized with the native host.

Abstract: The present invention relates to an ?-hemolysin-deletion mutant of SEs-producing Staphylococcus aureus and a construction method thereof. Said mutant is a genetically engineered strain obtained by deleting an ?-hemolysin (?-HL) gene of a wild type Staphylococcus aureus strain by a homologous recombination method. The genetically engineered strain has the same genetic background as the wild strain except no ?-hemolysin is produced.