E. Mechanical receptors are located in the lungs, upper airways, chest wall, and diaphragm which prevent overdistension of the lungs. F. Respiratory defense mechanisms: 1. filtration of air by the upper airways 2. mucociliary clearance system -which is decreased by infection, atropine, alcohol, dehydration,
However, one. of the most challenging aspects of forensic DNA analysis is the. interpretation of low-level testing results where it is difï¬cult to. distinguish reliably between noise and signal from template DNA. that is associated with an evidence sample (3,4).
The detection limit of a test is that concentration, at which the test starts to turn from negative to positive. Although the detection limit may vary between urine samples, the detection limit is defined as that concentration of the analyte that results in a positive reaction in 90% of the examined urines.