Assessing the Performance Capabilities of LRE-Based Assays for Absolute Quantitative Real-Time PCR

BACKGROUND: Linear regression of efficiency or LRE introduced a new paradigm for conducting absolute quantification, which does not require standard curves, can generate absolute accuracies of +/-25% and has single molecule sensitivity. Derived from adapting the classic Boltzmann sigmoidal function to PCR, target quantity is calculated directly from the fluorescence readings within the central region of an amplification profile, generating 4-8 determinations from each amplification reaction. FINDINGS: Based on generating a linear representation of PCR amplification, the highly visual nature of LRE analysis is illustrated by varying reaction volume and amplification efficiency, which also demonstrates how LRE can be used to model PCR. Examining the dynamic range of LRE further demonstrates that quantitative accuracy can be maintained down to a single target molecule, and that target quantification below ten molecules conforms to that predicted by Poisson distribution. Essential to the universality of optical calibration, the fluorescence intensity generated by SYBR Green I (FU/bp) is shown to be independent of GC content and amplicon size, further verifying that absolute scale can be established using a single quantitative standard. Two high-performance lambda amplicons are also introduced that in addition to producing highly precise optical calibrations, can be used as benchmarks for performance testing. The utility of limiting dilution assay for conducting platform-independent absolute quantification is also discussed, along with the utility of defining assay performance in terms of absolute accuracy. CONCLUSIONS: Founded on the ability to exploit lambda gDNA as a universal quantitative standard, LRE provides the ability to conduct absolute quantification using few resources beyond those needed for sample preparation and amplification. Combined with the quantitative and quality control capabilities of LRE, this kinetic-based approach has the potential to fundamentally transform how real-time qPCR is conducted

Developing two-way communication

To produce and disseminate information is only half the responsibility

Oral Argument in Meyer v. Holley (No. 01-1120)

The matter of Meyer v. Holley, 537 U.S. 280 (2003) was argued before the United States Supreme Court on Tuesday, December 3, 2002. Professor Robert G. Schwemm argued on behalf of the Respondents. This document is a transcript of the oral argument

Stable heat and moisture dissipation with dairy calves at temperatures of 50 degrees and 80 degrees F.

Missouri Agricultural Experiment Station and the United States Department of Agriculture cooperating.Includes bibliographical references (page 24)

Removal of terrestrial DOC in aquatic ecosystems of a temperate river network

Surface waters play a potentially important role in the global carbon balance. Dissolved organic carbon (DOC) fluxes are a major transfer of terrestrial carbon to river systems, and the fate of DOC in aquatic systems is poorly constrained. We used a unique combination of spatially distributed sampling of three DOC fractions throughout a river network and modeling to quantify the net removal of terrestrial DOC during a summer base flow period. We found that aquatic reactivity of terrestrial DOC leading to net loss is low, closer to conservative chloride than to reactive nitrogen. Net removal occurred mainly from the hydrophobic organic acid fraction, while hydrophilic and transphilic acids showed no net change, indicating that partitioning of bulk DOC into different fractions is critical for understanding terrestrial DOC removal. These findings suggest that river systems may have only a modest ability to alter the amounts of terrestrial DOC delivered to coastal zones

Megafirms

This paper documents and explains the amazing growth of the largest firms in law, accounting, and investment banking. Scholars to date have used various supply-side theories to explain the growth, and have generally examined only one industry at a time. We give the first demand-side explanation of firm growth, and show how the explanation is similar for firms in all project industries. We show that law plays an important role in determining industry structure. Among the areas we cover are the growth of Multi-Disciplinary Practice firms. We argue that the issues surrounding MDPs can best be understood by looking more broadly at the forces driving project industries. We also explain the driving forces behind the breakup of the Big Five accounting firms, the consolidation of the investment banking industry and the heretofore unexamined divergent growth patterns of the law firms in the plaintiffs\u27 securities litigation field

The construction and validation of informal skills inventories

Call number: LD2668 .T4 1969 S728Master of Scienc