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Displaying 126 - 150 of 2028

Sub-picoliter Traceability of Microdroplet Gravimetry and Microscopy

December 20, 2021
Author(s)
Lindsay C. C. Elliott, Adam L. Pintar, Craig R. Copeland, Thomas Brian Renegar, Ronald G. Dixson, Robert Ilic, R. Michael Verkouteren, Samuel M. Stavis
Volumetric analysis of single microdroplets is difficult to perform by ensemble gravimetry, whereas optical microscopy is often inaccurate beyond the resolution limit. To address the latter issue, we advance and integrate these complementary methods

Considerations in applying neutron depth profiling to Li-ion battery research

December 14, 2021
Author(s)
Daniel Lyons, Jamie Weaver, Anne Co
Li distribution within micron-scale battery electrode materials is quantified with neutron depth profiling (NDP). This method allows determination of intra- and inter-electrode parameters such as lithiation efficiency, electrode morphology change and Li

HDX-MS and MD simulations provide evidence for stabilization of the IgG1- FcgRIa (CD64a) immune complex through intermolecular glycoprotein bonds

December 8, 2021
Author(s)
Kyle Anderson, Kerry Scott, Christina Bergonzo, Ioannis Karageorgos, Elyssia Gallagher, Venkata Tayi, Michael Butler, Jeffrey W. Hudgens
Previous reports present different models for the stabilization of the Fc—FcγRI immune complex. Although accord exists on the importance of L235 in IgG1 and some hydrophobic contacts for complex stabilization, discord exists regarding the existence of

Characterization of Halogenated Organic Compounds in Pelagic Sharks and Sea Turtles Using a Nontargeted Approach

December 1, 2021
Author(s)
Aikebaier Renaguli, Sujan Fernando, Thomas Holsen, Philip Hopke, Douglas Adams, George Balazs, T Jones, Thierry Work, Jennifer Lynch, Bernard Crimmins
Halogenated organic compounds (HOCs) in marine species collected from the Atlantic Ocean [3 shortfin mako (Isurus oxyrinchus) and 1 porbeagle (Lamna nasus)], and 12 sea turtles collected from the Pacific Ocean [3 loggerhead (Caretta caretta), 3 green

Assessment of Serum Total 25-Hydroxyvitamin D Assays for Vitamin D External Quality Assessment Scheme (DEQAS) Materials Distributed at Ambient and Frozen Conditions

November 9, 2021
Author(s)
Johanna Camara, Christopher T. Sempos, Emma L. Williams, Graham D. Carter, Julia C. Jones, Carolyn Burdette, Grace Hahm, Federica Nalin, David L. Duewer, Adam J. Kuszak, J. M. Betz, Andrew Hoofnagle, Pierre Lukas, E. Cavalier, Ramon Durazo-Arvizu, P. M. Crump, Christian Popp, Christian Beckert, Glen Van Slooten, Patrick Gradon, Joelle Morgand, Sarah Paul, Bruno Emanuelli, Angelo Maggio, Fiona Ivison, Ralf Fischer, Jody M. van den Ouweland, Chung S. Ho, Emmett W. Law, Jean-Nicolas Simard, Renaud Gonthier, Brett Holmquist, Manisha S. Patwardhan, Marcelo C. Batista, Heather Pham, Sarah Meadows, Eugene Jansen, Dilshad A. Khan, Kimberly Robyak, Mark Kilbane, Neil Parker, Vincent Chen, Robert Fitzgerald, Sohail Mushtaq, Michael W. Clarke, Norma Breen, Christine Simpson, Stephen A. Wise
The Vitamin D External Quality Assessment Scheme (DEQAS) distributes human serum samples four times per year to over 1000 participants worldwide for the determination of total serum 25-hydroxyvitamin D [25(OH)D)]. These samples are stored at −40 °C prior

REFERENCE MATERIALS FOR TRACE ACTINIDE CONTENT IN PLUTONIUM OXIDE

October 1, 2021
Author(s)
Richard Essex, Lav Tandon, Cole Hexel, Amy Gaffney
Nuclear forensic analyses of plutonium (Pu) materials encountered outside nuclear safeguards control can include chemical composition, isotopic composition, and the concentration of various contaminants. Results from these measurements provide insights

An Introduction to the Benchmarking and Publications for Non-Targeted Analysis Working Group

September 29, 2021
Author(s)
Benjamin Place, Elin Ulrich, Jonathan Challis, Alex Chao, Bowen Du, Kristin Favela, Yong-Lai Feng, Christine Fisher, Piero Gardinali, Alan Hood, Ann Knolhoff, Andrew McEachran, Sara Nason, Seth Newton, Brian Ng, Jamie Nunez, Katherine Peter, Allison Phillips, Natalia Quinete, Ryan Renslow, Jon Sobus, Eric Sussman, Benedikt Warth, Samanthi Wickramasekara, Antony Williams
Non-targeted analysis (NTA) encompasses a rapidly evolving set of mass spectrometry techniques aimed at characterizing the chemical composition of complex samples, identifying unknown compounds, and/or classifying samples, without prior knowledge regarding

Certification of Standard Reference Material(R) 1936 Great Lakes Sediment

September 23, 2021
Author(s)
Jacqueline Bangma, Debra Ellisor, Michael Ellisor, N. Alan Heckert, Jennifer Hoguet, Kevin Huncik, Jennifer Ness, Jessica Reiner
Standard Reference Material (SRM) 1936 Great Lakes Sediment is intended for 1) use in validating calibration and validation materials for sediment analysis methods and 2) value assigning in house produced control materials analyzed using those methods. A

Experimental confirmation of long hyperbolic polariton lifetimes in monoisotopic (10B) hexagonal boron nitride at room temperature

September 14, 2021
Author(s)
Georges Pavlidis, Jeffrey Schwartz, Joseph Matson, Thomas Folland, Song Liu, James Edgar, Joshua Caldwell, Andrea Centrone
Hyperbolic phonon polaritons (HPhPs) enable arbitrarily high confinements, low losses, and directional propagation – providing opportunities from hyperlensing to flat optics, and other advanced nanophotonics applications. In this work, two near-field

Hidden Complexity in the Chemistry of Ammonolysis-Derived "gamma-Mo2N": An Overlooked Oxynitride Hydride

September 14, 2021
Author(s)
Rick L. Paul, Shobhit A. Pandey, Chi Zhang, Daniah H. Ibrahim, Elise A. Goldfine, Jill K. Wenderott, Roberto dos Reis, Ionnis Spanopoulos, Mercouri Kanatzidis, Michael J. Bedzyk, Vinayak P. Dravid, Gabriela B. Gonzalez, Sossina M. Haile
Molybdenum nitrides have been employed in a variety of catalysis and electronic applications. For use in catalysis, the cubic  phase with nominal stoichiometry Mo2N and space group Fm3 ̅m is typically prepared by high temperature reaction of MoO3 with NH3

Certification of Standard Reference Materials(R) 2969 and 2970: Vitamin D Metabolites in Frozen Human Serum (Total 25-Hydroxyvitamin D Low Level) and (25-Hydroxyvitamin D2 High Level)

September 2, 2021
Author(s)
Grace Hahm, Michael Nelson, Johanna Camara, Blaza Toman
Standard Reference Materials (SRMs) 2969 and 2970 are intended for 1) use in validating methods for determining concentrations of 25-hydroxyvitamin D2 (25(OH)D2) and 25-hydroxyvitamin D3 (25(OH)D3) in human serum and plasma and 2) value assigning in house

Interlaboratory Comparison of 25-Hydroxyvitamin D Assays: Vitamin D Standardization Program (VDSP) Intercomparison Study 2 - Part 2 Immunoassays - Impact of 25 Hydroxyvitamin D2 and 24R,25-Dihydroxyvitamin D3 on Assay Performance

August 27, 2021
Author(s)
Stephen Wise, Johanna Camara, Carolyn Burdette, Grace Hahm, Federica Nalin, Adam Kuszak, Joyce Merkel, Ramon Durazo-Arvizu, Emma Williams, Christian Popp, Christian Beckert, Jan Schultess, Glen Van Slooten, Carole Tourneur, Camille Pease, Kavi Kaul, Alfredo Villarreal, Marcelo Batista, Heather Pham, Alex Bennett, Eugene Jansen, Dilshad Khan, Mark Kilbane, Patrick Twomey, James Freeman, Neil Parker, Sohail Mushtaq, Christine Simpson, Pierre Lukas, Etienne Cavalier, Christopher Sempos
An interlaboratory comparison study was conducted by the Vitamin D Standardization Program (VDSP) to assess the performance of immunoassays (Part 2) for the determination of serum total 25 hydroxyvitamin D [25(OH)D]. A set of 50 single-donor samples was

Interlaboratory Comparison of 25-Hydroxyvitamin D Assays: Vitamin D Standardization Program (VDSP) Intercomparison Study 2 - Part 1 Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS) Assays - Impact of 3-epi-25-Hydroxyvitamin D3

August 27, 2021
Author(s)
Stephen Wise, Johanna Camara, Carolyn Burdette, Grace Hahm, Federica Nalin, Adam Kuszak, Joyce Merkel, Ramon Durazo-Arvizu, Emma Walker, Andrew Hoofnagle, Fiona Ivison, Ralf Fischer, Jody van den Ouweland, Chung Ho, Emmet Law, Jean-Nicolas Simard, Renaud Gonthier, Brett Holmquist, Sarah Meadows, Lorna Cox, Kimberly Robyak, Michael Creer, Robert Fitzgerald, Michael Clarke, Norma Breen, Pierre Lukas, Etienne Cavalier, Christopher Sempos
An interlaboratory comparison study was conducted by the Vitamin D Standardization Program (VDSP) to assess the performance of liquid chromatography – tandem mass spectrometry (LC-MS/MS) assays used for the determination of serum total 25-hydroxyvitamin D

Representing and Comparing Site-Specific Glycan Abundance Distributions of Glycoproteins

July 30, 2021
Author(s)
Concepcion Remoroza, Meghan Burke Harris, Yi Liu, Yuri Mirokhin, Dmitrii V. Tchekhovskoi, Xiaoyu (Sara) Yang, Stephen E. Stein
A method for representing and comparing distributions of N-linked glycans located at specific sites in proteins is presented. The representation takes the form of a simple mass spectrum for a given peptide sequence, with each peak corresponding to a

Fluorescence Microscopy Reveals Structure-Property Relationships and Polymer Dynamics in Biocomposites

July 21, 2021
Author(s)
Quinn Easter, Shawn Chen, Jeremiah Woodcock, Amanda Souna, Sindhu Seethamraju, Jan Obrzut, Douglas M. Fox, Stephan J. Stranick, Jeffrey Gilman
OBJECTIVES: Developing the next generation of materials for use in restorative work requires a multifaceted approach. While mimicking the properties of the tooth, currently available dental composites and porcelains eventually fail and require replacement
Displaying 126 - 150 of 2028