What is the threshold on the Applied Biosystems real-time PCR instruments and how do I set it?
The threshold is the numerical value assigned for each run that reflects the average dRn (change in fluorescence) during the initial cycles of PCR (baseline). The threshold is set by determining a statistically significant point (or value) above the baseline. You can manually adjust the threshold should you desire, to the place in the geometric phase where your replicates are tightest. For more information on how to manually set a threshold, please refer to the tutorial entitled Data Analysis on the ABI PRISM 7700: Setting Baselines and Thresholds (P/N 4370923). While this tutorial is based on the ABI PRISM 7700 system, the concepts are still valid for the Applied Biosystems real-time PCR instruments. You can search the document on our website by using the part number above as the keyword.
If you choose not to manually adjust the baselines and thresholds, the SDS software on the Applied Biosystems real-time PCR instruments has an Auto Ct algorithm that can be used to automatically generate baseline and threshold values for individual detectors. The algorithm calculates baseline and threshold parameters for a detector based on the assumption that the data exhibits the "typical" amplification curve. Experimental error (i.e. contamination, pipetting inaccuracies) can produce amplification curves that deviate significantly from a typical amplification curve. The data from these irregularities can affect the Auto Ct algorithm by causing it to generate incorrect baseline and threshold parameters for the associated detector. Therefore, Applied Biosystems recommends that after analysis of experimental data, you review all baseline and threshold parameters determined by the Auto Ct algorithm.
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Is the Applied Biosystems 7900HT SDS Automation Controller software and Zymark Twister Instrument compatible with MicroAmp Fast Optical 96-Well Reaction Plates with Barcode (P/N 4346906)?
No. The current version of the Zymark Twister Instrument and SDS Automation Controller software is NOT compatible with MicroAmp Fast 96-Well Optical Plates with Barcode. The Zymark Twister Instrument is compatible with MicroAmp Optical 96-Well Reaction Plate with Barcode, MicroAmp Optical 384-Well Reaction Plate with Barcode, as well as TaqMan Low Density Arrays.
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Why is my Applied Biosystems 7900HT SDS run file “read only” protected after the run has completed when using the SDS Automation Controller software and the Zymark Twister Instrument?
The file remains "read only" due to the status of the SDS Automation Controller Queue. The SDS run file in question still remains in the queue and must be cleared by the user within the SDS Automation Controller Software. To do this, the customer must open the SDS Automation Controller software, highlight the plate in question, select File -> Clear Selected Plates.
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What is the default user name and password for logging into the SDS 2.3 software?
When launching the SDS 2.3 software, you will be prompted for a user name and password. The default user name will be administrator and the default password field can be left blank. The user can simply click "OK" to launch the SDS 2.3 software. User accounts are configured by selecting TOOLS and then clicking LOCAL USER ACCOUNT MANAGER. Additional information regarding the LOCAL USER ACCOUNT MANAGER can be found by searching SDS 2.3 Online Help from the HELP pull down menu in the SDS 2.3 software.
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Where can I find a protocol to perform Fast TaqMan Real-Time PCR using the 384-well block on the Applied Biosystems 7900HT?
For detailed instructions on performing Fast TaqMan Real-Time PCR using the 384-well block on Applied Biosystems 7900HT, please refer to User Bulletin for Performing Fast TaqMan Gene Quantitation using 384 well plates on the Applied Biosytems 7900HT Fast-Real-Time PCR System with the 384 well Block Module. (P/N 4369584)
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