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Jorge O. Ona Ruales, Ruiz-Morales Yosadara, Stephen A. Wise
A methodology for the characterization of groups of PAHs using a combination of Normal Phase Liquid Chromatography with Ultraviolet-Visible Spectroscopy (NPLC/UV-vis) and Gas Chromatography with Mass Spectrometry (GC/MS) was used for the identification and
Brian E. Zimmerman, Denis E. Bergeron, Ryan P. Fitzgerald, Jeffrey T. Cessna
Tests for chemical stability were carried out on carrier-added 68Ge solutions prepared and calibrated in 2007 and 2011 to evaluate the suitability of the specific composition as a potential Standard Reference Material. Massic count rates of the stored
Jeffrey W. Hudgens, Richard Y. Huang, Emma D'Ambro
The chapter examines method validation and measurement standards for measuring protein dynamics by hydrogen/deuterium exchange mass spectrometry. Topics examined include the rationale for a reference measurement system for HDX-MS, attaining high accuracy
George C. Rhoderick, Duane Kitzis, Michael E. Kelley, Walter R. Miller Jr., Bradley Hall, Edward Dlugokencky, Pieter Tans, Antonio M. Possolo, Jennifer Carney
The National Institute of Standards and Technology (NIST) recently began to develop standard mixtures of greenhouse gases as part of a broad program mandated by the 2009 United States Congress to support research in climate change. To this end, NIST made
Aaron N. Johnson, Rodney A. Bryant, Tamae M. Wong, James R. Whetstone, Eric Harman, Woong Kang, Keith A. Gillis, Hsin-Hung Lee, Iosif I. Shinder, Liang Zhang
On April 20-21, 2015, NIST hosted a workshop that, through measurement science, enabled the owners of stationary sources (primarily the electric power industry) and their regulatory agencies (federal and state) to better characterize greenhouse gas (GHG)
Justin M. Zook, Hemang M. Parikh, Desu Chen, Hariharan K. Iyer, Marc L. Salit, Wolfgang Losert
The human genome contains variants ranging in size from small single nucleotide polymorphisms (SNPs) to large structural variants (SVs). While high-quality benchmark small variant calls have recently been developed by the Genome in a Bottle Consortium, no
Carl G. Simon Jr., John Test, Michael Yaszemski, Reto Luginbuehl, Anthony Ratcliffe, Paul Tomlins
A Workshop on Standards & Measurements for Tissue Engineering Scaffolds was held on May 21, 2013 and was sponsored by the American Society of Testing and Materials International (ASTM International) in Indianapolis, IN. The purpose of the workshop was to
Grady S. White, Adrian Verwolf, Chris M. Poling, Nicholas Barbosa, Nikki S. Rentz
Silicon wafers with micro-machined holes were evaluated for use as low permeation standard artifacts. Accuracy, stability, and reliability were assessed. Two experimental techniques were used: chilled mirror hygrometer and mass loss. The wafers exhibited a
Next-generation sequencing (NGS) is not routinely used in applied settings due to lack of confidence in results. This workshop convened experts to identify measurement challenges impeding NGS implementation and potential standards-based solutions to
Walter B. Wilson, Bassam Alfarhani, Cristina Bisson, Stephen A. Wise, Andres Campiglia
This article presents an alternative approach for the analysis of high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs) with molecular mass 302 Da in complex environmental samples. This is not a trivial task due to the large number of
There is a need for a common reference point that will allow for the comparison of the optical properties of tissue mimicking phantoms. This paper provides a brief review of the methods that have been used to measure tissue mimicking phantoms. The review
Marcus H. Mendenhall, Katharine Mullen, James P. Cline
This work presents an open implementation of the Fundamental Parameters Approach (FPA) models for analysis of X-ray powder diffraction line profiles. The original literature describing these models was examined and code was developed to allow for their use
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes
Jeanice M. Brown Thomas, David L. Duewer, Margaret C. Kline, Willie E. May, Sam A. Margolis, Neal E. Craft, Katherine E. Sharpless
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes
Jeanice M. Brown Thomas, David L. Duewer, Margaret C. Kline, Katherine E. Sharpless, Willie E. May, Sam A. Margolis, Neal E. Craft
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes
Marcus H. Mendenhall, Donald A. Windover, Albert Henins, James P. Cline
We present a simple way to collect data from an optical position or angle encoder with a readout which interpolates values between the optical features, and to process this data set so as to determine the short-range errors which arise from an
In this issue, Griffith et al. present one of the most comprehensive genome-sequence data sets to date from a patient with myeloid leukemia, including sequencing of normal tissue, primary cancer, and a relapse. Their raw data from a variety of sequencing
Carolyn R. Steffen, Margaret C. Kline, David L. Duewer, Peter Vallone
The NIST Standard Reference Material (SRM) 2391c: PCR-Based DNA Profiling Standard was updated in April 2015 to contain new information relevant to the forensic community. Previously, there were certified genotypes for 24 autosomal STR markers plus
Katherine E. Sharpless, David L. Duewer, Katrice A. Lippa, Andrew L. Rukhin
Although "nutraceuticals" and "functional foods" seem to be ill-defined terms, both are often used to indicate a food that contains compounds providing benefits beyond basic nutrition, often with the expectation that these compounds are protective against
Michael A. Nelson, Mary Bedner, Brian E. Lang, Blaza Toman, Katrice A. Lippa
Given the critical role of pure, organic compound primary reference standards used to characterize and certify chemical Certified Reference Materials (CRMs), it is essential that associated mass purity assessments be fit-for-purpose, represented by an
Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
Ultra-pure, carrier-free 209Po solution standards have been prepared and standardized for their massic alpha-particle emission rate. The standards, which will be disseminated by the National Institute of Standards and Technology (NIST) as Standard
Justin M. Zook, Anil Patwardhan, Marc L. Salit, Carlos Bustamante, Euan Ashley, Michael Snyder, John West, Richard Chen
Exome sequencing is increasingly used for the clinical evaluation of genetic disease, yet accuracy and coverage in medically interpretable parts of the genome remains under-characterized. We evaluate recently developed exome sequencing platforms in the
The two major forms of vitamin D, vitamin D3 and vitamin D2, are metabolized in the liver through hydroxylation to 25-hydroxyvitamin D species, and then further hydroxylated in the kidney to various dihydroxyvitamin D species. 24R,25-Dihydroxyvitamin D3