An automated data analysis method for real-time PCR needs to exhibit robustness to the factors that routinely impact the measurement and analysis of real-time PCR data. Robust analysis is paramount to providing the same interpretation for results regardless of the skill of the operator performing or reviewing the work. We present a new method for analysis of real-time PCR data, the maxRatio method, which identifies a consistent point within or very near the exponential region of the PCR signal without requiring user intervention. Compared to other analytical techniques that generate only a cycle number, maxRatio generates several measurements of amplification including cycle numbers and relative measures of amplification efficiency and curve shape. By using these values, the maxRatio method can make highly reliable reactive/nonreactive determination along with quantitative evaluation. Application of the maxRatio method to the analysis of quantitative and qualitative real-time PCR assays is shown along with examples of method robustness to, and detection of, amplification response anomalies.
Optical and EPR studies of K(H1−xDx)2PO4 (0⩽x⩽1) single crystals irradiated at 77°K with 60Co gamma rays and observed in liquid nitrogen, argon, and oxygen, have permitted not only the identification of two radical species produced as HPȮ−4 and H2PȮ4, but also a description of the annealing processes and their correlation with the ferroelectric transition temperature. Magnetic and kinetic parameters are given.
Absorption, excitation, and fluorescence spectra have been observed for thioindigo in benzoic acid host crystals at 1.4–4.2 K. The spectra reveal sites which arise from different tautometic forms of neighboring host dimer molecules. These sites exist in thermal equilibrium and interconvert during the excited state lifetime of thioindigo. The site interconversion process arises from a change in the tautomer configuration of a neighboring benzoic acid dimer due to proton tunneling. Fluorescence lifetime measurements for these sites give a direct measure of the proton tunneling rates in the excited state system at liquid helium temperatures k(H)tunneling =(4.45±0.10)×108 s−1. The deuteron tunneling rate is considerably slower in the acid deuterated host crystal k(D)tunneling =(4.9±1.5)×106 s−1. The acid protonated host crystal exhibits reversible hole burning phenomena for all thioindigo sites with recovery of the original line profile on the time scale of 1 min. The homogeneous linewidths obtained from hole burning measurements are not determined by the fluorescence lifetime of thioindigo. The additional contribution to the linewidth can be attributed to dephasing arising from site interconversion processes in both the ground and excited state system. A comparison of hole burning and fluorescence lifetime measurements provides a value for the proton tunneling rate in the ground state interconversion (equilibrium) process, k(H)tunneling =(3.5±1.3)×108 s−1. These results show that the hole burning phenomenon does not arise directly from these tunneling processes occurring in neighboring host dimers.
The interface of an automated analyzer to the laboratory workflow, notably system set up for samples and reagents and clean up functions, are as important as the automation capability of the analyzer for the overall impact to processing efficiency and operator hands-on time.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.