enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Numeric precision in Microsoft Excel - Wikipedia

    en.wikipedia.org/wiki/Numeric_precision_in...

    Excel maintains 15 figures in its numbers, but they are not always accurate; mathematically, the bottom line should be the same as the top line, in 'fp-math' the step '1 + 1/9000' leads to a rounding up as the first bit of the 14 bit tail '10111000110010' of the mantissa falling off the table when adding 1 is a '1', this up-rounding is not undone when subtracting the 1 again, since there is no ...

  3. Digital polymerase chain reaction - Wikipedia

    en.wikipedia.org/wiki/Digital_polymerase_chain...

    Real-time Digital PCR (rdPCR) combines the methodologies of digital PCR (dPCR) and quantitative PCR (qPCR), integrating the precision of dPCR with the real-time analysis capabilities of qPCR. This integration aims to provide enhanced sensitivity, specificity, and the ability for absolute quantification of nucleic acid sequences, contributing to ...

  4. Real-time polymerase chain reaction - Wikipedia

    en.wikipedia.org/wiki/Real-time_polymerase_chain...

    Real time PCR uses fluorophores in order to detect levels of gene expression. Cells in all organisms regulate gene expression by turnover of gene transcripts (single stranded RNA): The amount of an expressed gene in a cell can be measured by the number of copies of an RNA transcript of that gene present in a sample. In order to robustly detect ...

  5. Detection of genetically modified organisms - Wikipedia

    en.wikipedia.org/wiki/Detection_of_genetically...

    Quantitative PCR (Q-PCR) is used to measure the quantity of a PCR product (preferably real-time, QRT-PCR). [2] It is the method of choice to quantitatively measure amounts of transgene DNA in a food or feed sample. Q-PCR is commonly used to determine whether a DNA sequence is present in a sample and the number of its copies in the sample.

  6. Polymerase chain reaction optimization - Wikipedia

    en.wikipedia.org/wiki/Polymerase_chain_reaction...

    Chimeric polymerases overcome many limitations of native enzymes and are used in direct PCR amplification from cell cultures and even food samples, thus by-passing laborious DNA isolation steps. A robust strand-displacement activity of the hybrid TopoTaq polymerase helps solve PCR problems that can be caused by hairpins and G-loaded double ...

  7. Laboratory diagnosis of viral infections - Wikipedia

    en.wikipedia.org/wiki/Laboratory_diagnosis_of...

    One means of determining whether the cells are successfully replicating the virus is to check for a change in cell morphology or for the presence of cell death using a microscope. Other viruses may require alternative methods for growth such as the inoculation of embryonated chicken eggs (e.g. avian influenza viruses [ 4 ] ) or the intracranial ...

  8. Low copy number - Wikipedia

    en.wikipedia.org/wiki/Low_copy_number

    Low Copy Number (LCN) is a DNA profiling technique developed by the UK Forensic Science Service (FSS) which has been in use since 1999. [ 1 ] In the United Kingdom use of the technique was suspended between 21 December 2007 and 14 January 2008 while the Crown Prosecution Service conducted a review into its use – this suspension has now been ...

  9. Variants of PCR - Wikipedia

    en.wikipedia.org/wiki/Variants_of_PCR

    Colonies are sampled with a sterile pipette tip and a small quantity of cells transferred into a PCR mix. To release the DNA from the cells, the PCR is either started with an extended time at 95 °C (when standard polymerase is used), or with a shortened denaturation step at 100 °C and special chimeric DNA polymerase. [9]