Accuracy of lesion bypass by yeast and human DNA polymerase η

DNA polymerase η (Polη) functions in the error-free bypass of UV-induced DNA lesions, and a defect in Polη in humans causes the cancer-prone syndrome, the variant form of xeroderma pigmentosum. Both yeast and human Polη replicate through a cis-syn thymine-thymine dimer (TT dimer) by inserting two As opposite the two Ts of the dimer. Polη, however, is a low-fidelity enzyme, and it misinserts nucleotides with a frequency of ≈ 10−2 to 10−3 opposite the two Ts of the TT dimer as well as opposite the undamaged template bases. This low fidelity of nucleotide insertion seems to conflict with the role of Polη in the error-free bypass of UV lesions. To resolve this issue, we have examined the ability of human and yeast Polη to extend from paired and mispaired primer termini opposite a TT dimer by using steady-state kinetic assays. We find that Polη extends from mispaired primer termini on damaged and undamaged DNAs with a frequency of ≈ 10−2 to 10−3 relative to paired primer termini. Thus, after the incorporation of an incorrect nucleotide, Polη would dissociate from the DNA rather than extend from the mispair. The resulting primer-terminal mispair then could be subject to proofreading by a 3′→5′ exonuclease. Replication through a TT dimer by Polη then would be more accurate than that predicted from the fidelity of nucleotide incorporation alone.

Repeatability, reproducibility, and accuracy of a novel pushbroom hyperspectral system

This study analyzes the repeatability, reproducibility and accuracy of a new hyperspectral system based on a pushbroom sensor as a means of measuring spectral features and color of materials and objects. The hyperspectral system consisted of a CCD camera, a spectrograph and an objective lens. An additional linear moving system allowed the mechanical scanning of the complete scene. A uniform overhead luminaire with daylight configuration was used to irradiate the scene using d:45 geometry. We followed the guidelines of the ASTM E2214-08 Standard Practice for Specifying and Verifying the Performance of Color-Measuring Instruments that define the standards and latest multidimensional procedures. The results obtained are analyzed in-depth and compared to those recently reported by other authors for spectrophotometers and multispectral systems. It can be concluded that hyperspectral systems are reliable and can be used in the industry to perform spectral and color readings with a high spatial resolution.

Evaluation and research program of the U.S. censuses of population and housing, 1960 : accuracy of data on housing characteristics.

Mode of access: Internet.

Evaluation and research program of the U.S. censuses of population and housing, 1960 : accuracy of data on population characteristics as measured by reinterviews.

Mode of access: Internet.

Evaluation and research program of the U.S. censuses of population and housing, 1960 : accuracy of data on population characteristics for subgroups of the total population.

Bibliography: p. 76.

Study of the effects of turnout design on registration accuracy of propeller meters placed in downstream ends of turnout pipes /

Mode of access: Internet.

The accuracy of present wave forecasting methods : with reference to problems in beach erosion on the New Jersey and Long Island coasts /

Mode of access: Internet.

Accuracy of hydrographic surveying in and near the surf zone /

Mode of access: Internet.

Foreign assistance : accuracy of AID statistics on dollars flowing back to the U.S. economy is doubtful : report to the Chairman, Subcommittee on Foreign Operations, Export Financing, and Related Programs, Committee on Appropriations, House of Representatives /

"B-239036"--P. 1.

Locally asymptotically normal families of distributions; certain approximations to families of distributions and their use in the theory of estimation and testing hypotheses.

Bibliography: p. 98.

The précis book, or, Lessons in accuracy of statement and preciseness of expression /

Mode of access: Internet.