Accuracy, defined as the percentage difference between the nominal and the mean measured concentrations of quality controls, ranged from −4.1% (n = 74) to 6.4% (n = 75) during the analysis period.
In total, E2 was tested in five exposures at mean measured concentrations ranging from 1.0 to 723 ng/L, EE2 was tested in two exposures at concentrations ranging from 0.04 to 34 ng/L, and NP was tested in three exposures at concentrations ranging from 0.25 to 53 μg/L.
In the second experiment, designed to test the effect of pulsing larger quantities of -catechin into the soil, applications of total amounts of 0 (control), 340, 680 and 1020 µg g−1 of -catechin achieved mean measured concentrations over the course of the experiment of 1.4±1.4 (1SE), 14.5±5.8, and 36.1±10.2 µg g−1, respectively, in soils (Fig. 3).
To validate the assay procedure, the relative standard deviation (RS D%) and the relative error (RE %) of the mean measured concentration (n = 4) served as measures of accuracy and precision.
The actual applied concentrations were calculated based on the mean measured concentration directly before and after application.
The mean measured concentration of each chemical remained fairly constant over time: the measured concentrations of EE2, E2, NP, OP, and BPA 1 week and 2 weeks after the start of the exposure were an average of 99 and 77%, 89 and 92%, 92 and 96%, 84 and 97%, and 92 and 86% of those measured at the start of the exposure, respectively.
The relative error (RE %) of the mean measured concentration was also evaluated (Table 2).>> In recent decades, primary amino acid analysis have led to many improvements; probably one of the most popular has been the HPLC precolumn derivatization with OPA/thiol (Kutlan et al. 2002).
The mean measured iNDF concentrations for cows consuming low-, medium-, and high-concentrate diets were 178, 186, and 197 g/kg of DM, respectively.
Table 3 shows the mean measured albumin concentrations of samples spiked with bilirubin ranging from 0 to 500 μmol/L (samples 6 to 20 in Table 1).
The concentration of RDX in the water remained relatively stable during the 5-d exposure (Additional file 2: Table S2a) where mean measured exposure concentrations were 0.50, 0.93, 1.77, 3.67 and 7.18 mg/L.
During the exposure, mean measured water concentrations of CFA were 4.61 ± 0.58 μg/L and 18.58 ± 4.5 mg/L (mean ± SE, n = 18) for the 4 μg/L and 20 mg/L nominal tanks, respectively (Table 2).
