For comparisons, samples of different genotype were always examined in parallel, using the same reagents and cytometer settings, to eliminate differences resulting from day-to-day variations in instrument performance, reagent stability, etc.
The signals arising from these standards were used to correct data for variations in instrument performance that occur while a set of samples is being analyzed.
Internal standards, added in-line to samples and standards, were used for quantification and to correct for variations in instrument response.
Subjectivity of terms, variations in instrument, organizational differences in work settings, and cultural differences in the perception and reporting of pain and disorders are adduced for the variation in rates of WMSDs in the different studies.
Stained PBMCs were subsequently analyzed on an LSR Fortessa cytometer (BD), using Rainbow Fluorescent Particles (BD) and application settings in BDFACSDiva7 to correct for day-to-day variations in instrument performance.
The observed differences between electrolyte levels measured using an ABG and an AA may be explained by a combination of factors, including sample transport, dilution of serum samples prior to testing (thus, the use of indirect vs. direct electrodes), and variations in instrument calibration [ 16, 17].
Alternatively, proper deuterated hopanoids, that is, hopanoids incorporated with enough deuterium atoms to introduce a mass shift high enough to avoid overlap of isotope envelopes of labeled and unlabeled hopanoids, could be included in the samples as internal standards to account for variations in instrument conditions.
A data normalization step was performed to correct variation between instrument inter-day tuning differences.
Minor errors in the process, the continuous decrease of fiber extraction efficiency as well as the potential variation in instrument sensitivity can be eliminated by the use of internal standards.
Studies that test the effect of economic outcomes on political transitions using weather variations as instruments have generally overlooked findings from climate science that economic output is a hill-shaped, rather than linear, function of temperature and precipitation levels.
