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Wenwei Zheng, Alessandro Borgia, Karin Buholzer, Alexander Grishaev, Benjamin Schuler, Robert Best
Chemical denaturants are the most commonly used agent for unfolding proteins, and are thought to act by better solvating the unfolded state. Improved solvation is expected to lead to an expansion of unfolded chains by denaturant, providing a sensitive
Amy Chavis, Joseph Robertson, Joseph E. Reiner, Kyle Brady, Grrace Hatmaker, Nuwan Kothalawala
Sensing and characterization of water-soluble peptides is of critical importance in a wide variety of bioapplications. Single molecule nanopore spectrometry (SMNS) is based on the idea that one can use biological protein nanopores to resolve different
Prakash Kulkarni, Mohit Jolly, Dongya Jia, Steven Mooney, Ajay Bhargava, Luciane Kagohara, Yihong Chen, Pengyu Hao, Yanan He, Roberft Veltri, Alexander Grishaev, Keith Weninger, Herbert Levine, John Orban
Intrinsically disordered proteins (IDPs) that lack a unique 3D structure and comprise a large fraction of the human proteome play important roles in numerous cellular functions. Prostate- Associated Gene 4 (PAGE4) is an IDP that acts as a potentiator of
Dublin, Ireland beheld The 20th International Conference of Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2016) from October 23 to 27, 2016. The conference not only included a great technical program, but also outreach activities, an
Paul Lemaillet, Jeeseong Hwang, Heidrun Wabnitz, Dirk Grosenick, Lin Yang, David W. Allen
Diffuse materials that approximate the optical properties of human tissue are commonly used as phantoms. In order to use the phantoms in a manner that provides consistent results relative to independent measurements, the optical properties need to be tied
Philip Cheney, David McClatchy III, Stephen Kanick, Paul Lemaillet, David W. Allen, Daniel Samarov, Brian Pogue, Jeeseong C. Hwang
A hyperspectral dark-field microscopy technique has been developed for imaging spatially distributed diffuse reflectance spectra from light-scattering samples. In this report, quantitative scatter spectroscopy was demonstrated with a uniform scattering
Jeeseong Hwang, Hyun J. Kim, Paul Lemaillet, Dirk Grosenick, Thomas Gladytz, David McClatchy III, Kimberly A. Briggman, Brian Pogue
We report on a procedure to build and characterize solid tissue-mimicking phantoms of polydimethylsiloxane (PDMS) polymers. Controlled inclusion of light scattering titanium dioxide (TiO2) nanoparticles enables the creation of phantoms having tunable light
Danielle C. France, Jonathan Tejada, Paul Matsudaira
The ciliated protozoan Vorticella convallaria is noted for its exceptionally fast ATP-independent cellular contraction, but direct measurements of contractile force have proven difficult given the length scale, speed, and forces involved. We used high
Hannah E. Erdevig, Stephen E. Russek, Slavka Carnicka, Karl F. Stupic, Kathryn E. Keenan
Magnetic Resonance Imaging (MRI) is increasingly used to map the magnetic susceptibility of tissue to identify cerebral microbleeds associated with traumatic brain injury and pathological iron deposits associated with neurodegenerative diseases such as
The idea that size and shape can determine color is well known in optics-based quantum dot and plasmonic nanoparticle fields. But what about in the radio-frequency (RF) portion of the spectrum? This chapter reviews recent work on specially shaped magnetic
Michael Ondrusek, Veronica P. Lance, Eric Stengel, Menghua Wang, Zhongping Lee, Jianwei Wei, Junfang Lin, Chuanmin Hu, Charles Kovach, David English, Jennifer Cannizzaro, Alex Gilerson, Sam Ahmed, Carlos Carrizo, Ahmed El-Habashi, Robert Foster, Matteo Ottaviani, Robert Arnone, Sherwin Ladner, Wesley Goode, Ryan Vandermeulen, Nicholas Tufillaro, Jasmine Nahorniak, Curtiss Davis, Joaquim I. Goes, Kali McKee, Scott Freeman, Joaquin E. Chaves Cedeno, Kenneth Voss, B. Carol Johnson
Yun Jiang, Dan Ma, Katy Keenan, Karl Stupic, Vikas Gulani, Mark Griswold
Purpose: The purpose of this study was to evaluate accuracy and repeatability of T 1 and T 2 estimates of a MR fingerprinting (MRF) method using the ISMRM/NIST MRI system phantom. Methods: The ISMRM/NIST system phantom contains multiple compartments with
Gabriella Captur, Peter Gatehouse, Katy Keenan, Friso Heslinga, Ruediger Bruehl, Marcel Prothmann, Martin J. Graves, Richard J. Eames, Camilla Torlasco, Giulia Benedetti, Jacqueline Donovan, Bernd Ittermann, Redha Boubertakh, Andrew Bathgate, Celine Royet, Wenjie Pang, Reza Nezafat, Michael Salerno, Peter Kellman, James C. Moon
Background: T1 mapping and extracellular volume (ECV) have the potential to guide patient care and serve as surrogate end-points in clinical trials, but measurements differ between cardiovascular magnetic resonance (CMR) scanners and pulse sequences. To
Alexander Peterson, Michael Halter, Anne Plant, John Elliott
Surface plasmon resonance imaging (SPRI) allows real-time label-free imaging based on index of refraction, and changes in index of refraction at an interface. SPRI can be carried out on a microscope by launching light into a sample, and collecting
Karl F. Stupic, Janusz H. Hankiewicz, Zbigniew Celinski, Robert E. Camley
We explore the possibility of using small ferromagnetic particles with a strong temperature- dependent magnetization to produce temperature maps using magnetic resonance imaging (MRI). We present the first experimental results showing that the 1H nuclear
Alexander V. Grishaev, Lalit Deshmukh, Charles Schwieters, G. Marius Clore
Nucleic-acid-related events in the HIV-1 replication cycle are mediated by nucleocapsid, a small protein comprising two zinc knuckles connected by a short flexible linker and flanked by disordered termini. Combining experimental NMR residual dipolar
Jessica H. Benjamini, John J. Kasianowicz, Arvind K. Balijepalli
We report a new technique to characterize poly- oxometalate (POM) structures at micromolar solution concentra- tion using single molecule nanopore-based measurements. The pH-dependent structural changes in phosphotungstic acid deter- mined with this
Carl Fuller, Shiv Kumar, Mintu Porel, Michen Chien, Arek Bibillo, P. B. Stranges, Michael Dorwart, Chuanjua Tao, Zengmin Li, Wenjing Guo, Shundi Shi, Daniel Korenblum, Andrew Trans, Anne Aguirre, Edward Liu, Takeshi Harada, James Pollard, Ashwini Bhat, Cynthia Cech, Alexander Yang, Cleoma Spilman, Mirko Palla, Jennifer Hovis, Roger Chen, Irina Morozova, Sergey Kalachikov, James Russo, John J. Kasianowicz, Stefan Roever, George Church, Jingyue Ju
DNA sequencing by synthesis (SBS) offers a robust platform to decipher nucleic acid sequences. Recently, we developed a single molecule nanopore-based SBS strategy (NanoSBS) that accurately distinguishes four bases by electronically detecting and
Paul Lemaillet, Catherine C. Cooksey, Zachary H. Levine, Adam L. Pintar, Jeeseong Hwang, David W. Allen
The National Institute for Standards and Technology (NIST) has maintained scales of reflectance and transmittance over several decades. Those scales are primarily intended for the regular transmittance, mirrors, and solid surface scattering diffusers. The
Using NIST-calibrated solutions of 131Ba and 131I in the 5 mL NIST ampoule geometry, measurements were made in three NIST-maintained Capintec activity calibrators and the NIST Vinten 671 ionization chamber to evaluate the suitability of using 133Ba as a
Kathryn E. Keenan, Sheye O. Aliu, Lisa J. Wilmes, David C. Newitt, Ella F. Jones, Wen Li, Michael A. Boss, Karl F. Stupic, Stephen E. Russek, Nola M. Hylton
Purpose: To assess the ability of a recent, anatomically designed breast phantom incorporating T 1 and diffusion elements to serve as a quality control device for quantitative comparison of apparent diffusion coefficient (ADC) measurements calculated from
Fang Li, Alexander Grishaev, Jinfa Ying, Adriaan Bax
Accurate quantitative measurement of structural dispersion in proteins remains a prime challenge to both X-ray crystallography and NMR spectroscopy. An approach based on measurement of many residual dipolar couplings (RDCs) in differentially orienting
A new optical scattering contrast-agent based on polymer- nanoparticle encapsulated silver nanoplates (PESNs) is presented. Silver nanoplates were chosen due to the flexibility of tuning their plasmon frequencies. The polymer coating preserves their