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NIST Authors in Bold

Displaying 601 - 625 of 1845

Variables in the Quantification of CD4 in Normals and Hairy Cell Leukemia Patients

January 3, 2011
Author(s)
Gerald E. Marti, William G. Stetler-Stevenson, Fatima Abbasi, Gregory A. Jasper, Robert J. Kreitman, Lili Wang
Background: Quantitative flow cytometry (QFCM) is being applied in the clinical flow cytometry laboratory. Quantitative normal T-cell CD4 expression represents a biologic standard and quality control agent. However, Low levels of CD4 expression were

Measurement of Nanoparticle Concentration Using Quartz Crystal Microgravimetry

December 16, 2010
Author(s)
Vytautas Reipa, Geoffrey Purdum, Jonghoon Choi
A common issue, encountered in nanoparticle-biological system interaction studies is accurate nanoparticle concentration expression, given the critical importance of the dose-response relationships. We present here the application of quartz crystal

Ordered metal nanostructure self-assembly using metal-organic frameworks as templates

December 13, 2010
Author(s)
Benjamin Jacobs, Houk Ronald, Stephen House, Ian Robertson, Albert A. Talin, Mark Allendorf, Mitchell Anstey
Synthesis of metal nanoparticles and nanowires with controlled size and aspect ratio is well developed,1-4 but the creation of ordered nanostructures comprising these is much more challenging, presenting a barrier to further development of electronic and

Microstructure and hydrogen bonding in water-acetonitrile mixtures

November 19, 2010
Author(s)
Raymond D. Mountain
The connection between hydrogen bonding between water and acetonitrile in determining the microheterogeneity of the liquid mixture is examined using NPT molecular dynamics simulations. Mixtures for six, rigid, three-site models for acetonitrile and one

Novel Reduced Pressure-Balance Syringe for Chromatographic Analysis

November 19, 2010
Author(s)
Bret Windom, Thomas J. Bruno
When withdrawing a fluid sample from an apparatus at reduced pressures for additional chromatographic analyses, a gas tight plunger syringe proves ineffective as it does not create a substantial pressure differential to pull a fluid from a reduced pressure

Association of Quantum dot nanoparticles with Pseudomonas aeruginosa biofilm

November 1, 2010
Author(s)
Jayne B. Morrow, Catalina Arango, Richard D. Holbrook
Quantum dots (QDs) of two different surface chemistries (carboxyl (COOH) and poly ethylene glycol (PEG) modified) were utilized to determine the impact of surface functionality on QD mobility and distribution in Pseudomonas aeruginosa PAO1 biofilms

Development of a Candidate Secondary Reference Procedure (immunoassay based measurement procedure of higher metrological order) for Cardiac Troponin I: I. Antibody Characterization and Preliminary Validation

November 1, 2010
Author(s)
James E. Noble, David M. Bunk, R. H. Christenson, Kenneth D. Cole, Hua-Jun He, Alexei Katrukha, Mauro Panteghini, Robert Porter, Heinz Schimmel, Jillian Tate, Lili Wang
The development of a reference measurement procedure to support the cardiac troponin I (cTnI) standardization initiative is described. The reference measurement procedure will be used to assign reference values to serum-based secondary standards. A

The Roles of the Mise en Pratique for the Definition of the Kelvin

October 16, 2010
Author(s)
Dean C. Ripple, Richard Davis, Bernd Fellmuth, Joachim Fischer, Graham Machin, Terry Quinn, Peter Steur, Osamu Tamura, David R. White
The mise en pratique (“practical realization”) for the definition of the kelvin (MeP-K) was created by the Consultative Committee for Thermometry (CCT) in 2006 to give practitioners of thermometry a guide to the realization of the kelvin, in accord with

Bilateral Comparison Confirms NIM’s and NIST’s Gas Flow Capabilities

October 15, 2010
Author(s)
Aaron N. Johnson, CHUNHUI LI
The bilateral comparison between NIM and NIST for gas flow was conducted from June 2008 to October 2009. Two critical flow venturis (CFVs) with nominal throat diameters of 10 mm and 20 mm, respectively, were selected as transfer standards. The CFVs were

Properties for Accurate Gas Flow Measurements

October 15, 2010
Author(s)
John D. Wright
Accurate gas properties are needed to take full advantage of the low uncertainties provided by NIST’s Gas Flow Calibration Services. If a flowmeter user and NIST use different values for these properties (molecular mass, compressibility, density, viscosity

Chromatographic Methods for the Quantification of Free and Chelated Gadolinium Species in MRI Contrast Agent Formulations

October 3, 2010
Author(s)
Danielle Cleveland, Stephen E. Long, Lane C. Sander, William C. Davis, Karen E. Murphy, Catherine A. Rimmer, Lorena Francini, Anil K. Patri
Speciation measurements of gadolinium in liposomal MRI contrast agents are complicated by the presence of emulsifiers, surfactants, and therapeutic agents in the formulations. The present paper describes two robust, hyphenated chromatography methods for

Thermochemistry of Imidazolium-Based Ionic Liquids:Experiment and First-Principles Calculations

September 16, 2010
Author(s)
Chris D. Muzny, Sergey P. Verevkin, Vladimir N. Emel'yanenko, Dzmitry H. Zaitsau, Andreas Heintz, Michael D. Frenkel
In this work the molar enthalpy of formation of the ionic liquid ethyl-methylimidazolium dicyanoamide in the gaseous phase [C2MIM][N(CN)2] was measured by means of combustion calorimetry and enthalpy of vaporization using transpiration. Available scarce

BioPAX A Community Standard for Pathway Data Sharing

September 9, 2010
Author(s)
Robert N. Goldberg, Michael Cary, Erek Demir
BioPAX (Biological Pathway Exchange) is a standard language to represent biological pathways and processes at the molecular and cellular level. Its major use is to facilitate the exchange of pathway data (http://www.biopax.org). Pathway data captures our

Scientific Issues with Analysis of Low Amounts of DNA

September 7, 2010
Author(s)
John Butler, Becky Steffen
Faced with limited evidence that yield low amounts of DNA, forensic analysts will continually have to confront the question of how far to push DNA testing techniques. Low copy number (LCN) analysis, also known as low template DNA (LT-DNA) testing, involves
Displaying 601 - 625 of 1845