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Marcus H. Mendenhall, David R. Black, James P. Cline
Abstract The use of an Incident Beam Monochromator (IBM) or multilayer focusing mirror in an X- ray powder diffractometer modifies both the shape of the spectrum from the X-ray source, and the relation between the apparent diffracted angle and the actual
Richard Essex, Ross W. Williams, Kerri C. Treinen, Ronald Colle, Ryan P. Fitzgerald, Raphael Galea, John Keightley, Jerome LaRosa, Lizbeth Laureano-Perez, Svetlana Nour, Leticia Pibida
A 231Pa reference material has been characterized for amount of Pa. This reference material is primarily intended for calibration of 233Pa tracers produced for 231Pa - 235U model age measurements associated with nuclear forensics and nuclear safeguards
The DNA sequencing technologies in use today produce either highly accurate short reads or less-accurate long reads. We report the optimization of circular consensus sequencing (CCS) to improve the accuracy of single-molecule real-time (SMRT) sequencing
Barbara J. Belzer, Kari K. Harper, Titilayo O. Shodiya
NIST Handbook 150-2, 2019 edition, presents the technical requirements and guidance for the accreditation of laboratories under the National Voluntary Laboratory Accreditation Program (NVLAP) Calibration Laboratories Program. The 2019 edition of NIST
Justin M. Zook, Nathanael D. Olson, Marc L. Salit, Aaron Wenger, Chunlin Xiao, Robert Sebra
Genome In a Bottle (GIAB) is a consortium hosted by the National Institute of Standards and Technology whose primary objective is the development and characterization of human genomic reference materials. The consortium includes representatives from
This report documents our evaluation of three digital PCR (dPCR) based methods for estimating the proportion, if any, of single-stranded DNA (ssDNA) in a sample that is believed to be mostly double-stranded DNA (dsDNA). These methods are: 1) a modification
John R. Sieber, Antonio M. Possolo, Michael S. Epstein
Many older certified reference materials have certificates of analysis that do not fully comply with ISO Guide 31. This applies to many NIST Standard Reference Materials (SRM) that have published uncertainty estimates not compliant with the GUM or have no
Walter B. Wilson, Lane C. Sander, Benjamin J. Place, James H. Yen
Standard Reference Material (SRM) 3389 is intended as a calibration solution for use for the determination of ginsenosides in natural matrix samples. A unit of SRM 3389 consists of two different ampule solutions: (1) four ampules of a six-component mixture
Dean C. Ripple, Srivalli Telikepalli, Kristen L. Steffens, Michael J. Carrier, Christopher B. Montgomery, Nicholas W. Ritchie, John Lu
Reference Material (RM) 8634 is a NIST particle standard produced from abraded ethylene tetrafluoroethylene (ETFE), a chemically inert polymer, that will help standardize and allow more accurate monitoring of subvisible proteinaceous particles in
Blanka Halamoda-Kenzaoui, Simon Baconnier, Thierry Bastogne, Didier Bazile, Patrick Boisseau, Gerrit Borchard, Sven E. Borgos, Luigi Calzolai, Karin Cederbrant, Gabriella di Felice, Tiziana Di Francesco, Marina Dobrovolskaia, Rog?rio Gaspar, Bel?n Gracia, Vincent A. Hackley, Lada Leyens, Neill Liptrott, Margriet Park, Anil Patri, Gert Roebben, Matthias Roesslein, Ren? Th?rmer, Patricia Urb?n L?pez, Val?rie Zuang, Susanne Bremer-Hoffmann
The workshop "Bridging communities in the field of nanomedicine" was hosted by the European Commission Joint Research Centre on 27-28 September 2017. It gathered experts from regulatory bodies, research institutions and industry to discuss the main
Justin M. Zook, Jennifer H. McDaniel, Marc L. Salit, Nathanael D. Olson, Justin M. Wagner
Benchmark small variant calls are required for developing, optimizing and assessing the performance of sequencing and bioinformatics methods. Here, as part of the Genome in a Bottle (GIAB) Consortium, we apply a reproducible, cloud-based pipeline to
Any eSPM measurement of a spatially varying electric field at the surface of a sample has a large uncertainty due to the unknown details of the tip shape near the surface. We have designed an electric field gradient reference sample to provide an
David L. Duewer, Katrice A. Lippa, Blaza Toman, Tang Lin Teo, Qinde Liu, Pui Sze Cheow
The 2017 CCQM-K142 Comparison of CRMs and Value-Assigned Quality Controls: Urea and Uric Acid in Human Serum or Plasma is the third Key Comparison directly testing the chemical measurement services provided to customers by National Metrology Institutes
Standardized benchmarking approaches are required to assess the accuracy of variants called from sequence data. Although variant- calling tools and the metrics used to assess their performance continue to improve, important challenges remain. Here, as part
Justin M. Zook, Marc L. Salit, Steve Lincoln, Matthew Lebo
The confirmation of genetic variants identified by next-generation sequencing (NGS) using orthogonal assays (e.g., Sanger sequencing) is standard practice in many laboratories. Published studies have examined this issue, concluding that confirmation of the
Jasper A. Drisko, Ari D. Feldman, Franklyn J. Quinlan, James C. Booth, Nathan D. Orloff, Christian J. Long
Light has been widely used to control a variety of microwave devices, including switches, antennas, and detectors. Here, we present a photoconductive device integrated into a coplanar waveguide to tune complex impedances at microwave frequencies with
Justin M. Zook, Marc L. Salit, Peyton Greenside, Ryan Poplin, Mark DePristo, Madeleine Cule
Copy number variants (CNVs) are an important type of genetic variation and play a causal role in many diseases. However, they are also notoriously difficult to identify accurately from next-generation sequencing (NGS) data. For larger CNVs, genotyping
A combination of thermal neutron (TN) and cold neutron (CN) PGAA has been used to improve accuracy, precision, detection limits, and sample throughput time in PGAA. CNPGAA was used to measure element ratios relative to a comparator element, while TNPGAA
John Bowden, Candice Z. Ulmer, Christina Jones, Richard A. Yost, Timothy J. Garrett
In order to investigate changes in the lipidome, analysis by ultra-high performance liquid chromatography - high resolution mass spectrometry (UHPLC-HRMS) typically requires the extraction of lipid content from sample matrices using optimized, matrix
For over 40 years, food-matrix certified reference materials (CRMs) have been available for the determination of trace element content, and a wide variety of materials are available from most producers of CRMs. However, the availability of food-matrix CRMs
Solutions of organic analytes of known mass fraction are typically used to calibrate the measurement processes used to determine these compounds in matrix samples. Appropriate value assignments and uncertainty calculations for calibration solutions are
David L. Duewer, Jacolin A. Murray, Laura J. Wood, Stephen A. Wise
Extraction, chromatographic separation, and quantification of low-concentration organic compounds in complex matrices are core challenges for reference material producers and providers of calibration services. Evidence of successful participation in formal
This article describes work carried out to determine test cycle sensitivity coefficients for the Rockwell HR45N hardness scale. Sensitivity coefficients were determined for the preliminary- force, total-force and recovery-force dwell times. The work was
This paper describes a new design for HRBW scale reference blocks, that has the potential to greatly reduce the bending of brass blocks and thus improve short time stability of the blocks apparent reference value. The experimental results given here are
NIST Handbook 150-8 presents technical requirements and guidance for the accreditation of laboratories under the National Voluntary Laboratory Accreditation Program (NVLAP) Acoustical Testing Services program. It is intended for information and use by