This may be due to a) test-specific learning, a change in stimulus salience in relation to the test (a known artefact of repeat-testing especially in the case of "novel object tests"), b) added error through the additional computational step of multivariate statistical analysis, or c) general maturation effects of the animal.
Spleen cells from systemic high-dose BCG-treated mice were found to exert a strong nonspecific cytostatic effect in vitro that was not an artefact of the test conditions, and was not expressed by cells from low-dose animals.
First, it is not clear whether the rise in reported STIs reflects a genuine rise in incidence or is an artefact of more widespread testing (leading to more true positives being picked up).
To rule out tissue culture artefacts, we tested the antiviral activity of iota-carrageenan against influenza in primary HNep cells.
The significance of reductions in gamma with artefact correction was tested, across subjects, for each cohort separately, using one-tailed t tests.
Low-scoring, taxonomically restricted orphans are most likely to be annotation artefacts: we tested this in the case of E. coli K12 by reference to online transcriptomic and proteomic expression data.
Alternatively, the "donor" effect may be a statistical artefact of the Tukey-Kramer test which, when used to contrast variable numbers of regenerants within a data set, compares the sets in pairs, and thus is capable of delivering a non-existent "genotype" effect.
Furthermore, a haplotype using a set of SNPs surrounding the associated SNP and which correlated with the genotype, also detected the association suggesting that this is not an artefact at the tested SNP.
Careful attention has been paid to artefact testing of the non-rigid registration method used, and the importance of this registration for the quantitative interpretation of feature intensities and positions is evaluated.
Different types of artefacts were investigated in a variety of locations, testing and demonstrating the flexibility in instrumental set-up.
