In the United States Army Special Forces, the motto is traditionally believed to mean to free from oppression or to liberate the oppressed in English. A correct translation of the phrase de oppresso liber would be from (being) an oppressed man, (to being) a free one. The preposition de here means from in the sense of a change from one status to another, not intending separation from the oppressed, but moving from a source in the oppressed.
Qualitative hCG testing detects the presence of hCG and is routinely used to screen for a pregnancy. This test may be performed by a laboratory, at a doctor's office, or at home using a home pregnancy test kit.
The initial screening process at the lab separates the negative from non negative results. GCMS testing is an extremely accurate test that is completed on non negative results which provides quantitative results for the presence of a specific drug or drug metabolite.