Importantly, we found independent statistical main effects on the large-scale organization of gene expression levels for biological factors associated with the sample and technical factors associated with the testing site with no statistical interaction (figure 7).
In addition, one patient sample and technical replicates from two of the 11 patient samples were prepared according to the manufacturer's recommendations at the Helsinki Biomedicum Biochip Centre (BBC), where 15 control samples had been previously prepared.
Follow-up samples and technical replicates for a given (subject, body site) combination were excluded to avoid biasing population estimates in their direction.
These limitations include complicated and time-consuming protocol, requirement for specific tools and expert personnel for performing of the method, low signal-to-noise ratio, the risk of cross-contamination among different samples when assaying multiple samples, and technical hurdles in the preparation of detection of antibody-signal DNA conjugates.
The remaining 1,426 candidate RAD alleles grouped into 1,055 binary patterns and are likely to be a result of a combination of sampling and technical error.
Dye swap quality control experiments were performed with two samples and technical replicates performed with five samples.
The success of vitrification depends on many factors such as sample size, type and concentration of cryoprotectants, temperature of exposure to vitrification solution, stepwise addition of vitrification solution, carrier system, quality of samples, and technical expertise [ 13].
First, although at least 16 phthalate metabolites in urine can be measured (Kato et al. 2005), we measured only three, based on children's likely exposure, availability of standard samples, and technical experience of the analyses.
The number of proteins in the genome is 46147 (http://phytozome.jgi.doe.gov/pz/portal.html#!info alias=Org_Csinensis), due to the reasons of samples and technical restrain, 4160 identified proteins in current proteomic research is normal in plants.
The limma algorithm in FlexArray, based on the limma package in bioconductor [ 25] was used for the direct comparison of two COC samples and technical replicates of pooled embryos from 2-cell, 4-cell and 8-cell stages after dye-swaps.
A recent paper by Cairns et al 2009 [ 28] addressing sample size and technical and biological variation, states the significance of performing in house tests on protocol and sample size.
