Introduced in 1.6 to support modifier term within the metadata table, the _M_APPLIED_PATH_ is the CONCEPT_PATH that the term applies to. Traditional (non-modifier) concept terms have a M_APPLIED_PATH of '@'.
An M_APPLIED_PATH of '\Diagnoses\Circulatory system%' means that the term is a modifier that applies to the term(s) with C_FULLNAME of '\Diagnoses\Circulatory system\' and all its descendants, whereas a M_APPLIED_PATH of '\Diagnoses\Circulatory system\' applies to the term with C_FULLNAME of '\Diagnoses\Circulatory system\' only.