Showing papers in "Journal of Magnetic Resonance in 2016"

TL;DR: Dissolution-DNP is a method to create solutions of molecules with nuclear spin polarization close to unity as mentioned in this paper, which has enabled many new applications, in particular in vivo MR metabolic imaging.

TL;DR: The current state of the art of solid-state DNP NMR instrumentation primarily based on available commercial platforms is reviewed and specific developments for DNP at 100K with magic angle spinning (MAS) are focused on.

TL;DR: A novel experimental design and processing framework to accelerate and improve the reconstruction of 2D relaxation spectra that uses a priori information from the 1D projections of spectra, or marginal distributions, and is demonstrated here with a polyvinylpyrrolidone-water phantom.

TL;DR: Adapting pulse sequences from classic NMR and EPR, and combined with high resolution optical microscopy, proximity to the target sample and nanoscale size, the diamond sensors have the potential to constitute a new class of magnetic resonance detectors with single spin sensitivity.

TL;DR: A novel double-stripline NMR probe head is presented that accommodates planar microfluidic devices, and obtains the NMR spectrum from a rectangular sample chamber on the chip with a volume of 2μl, comparing very favourably with other micro-NMR systems.

TL;DR: This work overviews recent efforts on hardware developments, specifically targeted on improving DNP MAS NMR at high fields, and describes the development of gyrotrons that enable continuous frequency tuning and rapid frequency modulation for two DNP NMR spectrometers.

TL;DR: It is shown that using ultra-low temperatures for MAS-DNP results in substantial experimental sensitivity enhancements and according time-savings, and access to this temperature range is demonstrated to be both viable and highly pertinent.

TL;DR: A Bayesian statistical approach is introduced that quantifies uncertainty in P(r) arising from noise and numerical regularization and provides credible intervals (error bars) of P( r) at each r, which allows practitioners to answer whether or not small features are significant,Whether or not apparent shoulders aresignificant, and whether orNot two distance distributions are significantly different from each other.

TL;DR: Novel instrumentation for low-temperature solid state nuclear magnetic resonance (NMR) with dynamic nuclear polarization (DNP) and magic-angle spinning (MAS) is described, focusing on aspects of this instrumentation that have not been described in detail in previous publications.

TL;DR: The aim of this article is to provide an overview of the current state-of-the-art technology for preclinical applications and the challenges that need to be addressed to promote it and allow its wider dissemination in the near future.

TL;DR: A summary of state of the art DNP MAS NMR spectroscopy and its applications to structural biology is presented, discussing the technical challenges and factors affecting DNP performance.

TL;DR: The consequences of symmetry-induced constraints on spin dynamical evolution are examined for some common hyperpolarized NMR experiments, including the excitation of singlet order in spin-pair systems, and the transfer of parahydrogen-induced hyperPolarized singlet Order to magnetization in systems displaying chemical and magnetic equivalence.

TL;DR: It is demonstrated that the proposed NMR technique to create singlet spin order from longitudinal spin magnetization in coupled spin-½ pairs works perfectly for both strongly and weakly coupled spin pairs, providing a conversion efficiency which is equal to the theoretical maximum.

TL;DR: These long-range homonuclear couplings are experimentally determined for several SABRE substrates using an NMR pulse sequence for coherent hyperpolarization transfer at high magnetic field.

TL;DR: The theoretical premises of Overhauser DNP in solution are recapitulated and the effects of the various parameters on the efficacy of the mechanism are analyzed, underlining the link between the DNP enhancements and the field dependent relaxation properties.

TL;DR: A device for performing fast magnetic field-cycling NMR experiments that combines fast switching of the external magnetic field and high-resolution NMR detection is described and advantages of the experimental method are described and existing challenges in the field are outlined.

TL;DR: Many difficult NMR, EPR and MRI simulation problems are simplified significantly in Fokker-Planck space - the methods described below have enabled a large variety of simulations previously considered too complicated for routine practical use.

TL;DR: The provisions that lead to these significant improvements over previous reports are detailed, and 1D coherence transfer experiments and 2D biomolecular HMQC acquisitions delivering NMR spectral enhancements of 100-500× over their optimized, thermally-polarized, counterparts are demonstrated.

TL;DR: A new Automatic Tuning Matching Cycler in situ NMR probe system is developed and explored to track the formation of intermediate phases and investigate electrolyte decomposition during electrochemical cycling of Li- and Na-ion batteries (LIBs and NIBs).

TL;DR: A new methanethiosulfonate derivative of a TAM radical that reacts rapidly and selectively with an engineered cysteine residue to generate a TAM containing side chain (TAM1) in high yield is reported.

TL;DR: A modified d-DNP recipe is introduced that can be summed up as follows: using broad line polarizing agents to efficiently polarize 1H spins, and transferring hyperpolarized solution through a magnetic tunnel.

TL;DR: This study provides a tool for the decoupling of dipole antennas in ultrahigh field transceive arrays, possibly resulting in denser element placement and/or larger subject-element spacing.

TL;DR: A computational scheme for calculating the coupling factors from molecular dynamics (MD) simulations is outlined and used to highlight the limitations of the classical models based on translational and rotational motion that are typically employed to quantify the observed coupling factors.

TL;DR: In this article, the arterial input function (AIF) measured from individual arteries sometimes requires amplitude scaling for better representation of the blood contrast reagent (CR) concentration time-courses.

TL;DR: The detailed design of a DNP instrument, powered by a solid-state MW source that is tunable between 193 and 201 GHz and outputs up to 140 mW of MW power, is described, suitable for future upgrades and extensions to include new experimental capabilities to meet contemporary DNP needs.

TL;DR: The MRI flow measurements demonstrated the diurnal changes in flow velocity in the stem on a per-pixel basis and demonstrate that the outdoor MRI system is a powerful tool for studies of water transport in outdoor trees.

TL;DR: Experimental data and theoretical interpretation of NMR spectra of remotely magnetized samples, detected in an unshielded environment by means of a differential atomic magnetometer are presented, which are satisfactorily interpreted.

TL;DR: Improvements are proposed for practical design and use of high permittivity materials in high field neuroimaging in three different areas: characterization of addition of a hydroxyethyl-cellulose gelling agent to improve the long-term stability and material properties of "dielectric pads".

TL;DR: Comprehensive derivations for the statistical models and methods for the use of pulsed gradient spin echo (PGSE) NMR to characterize the molecular weight distribution of polymers via the well-known scaling law relating diffusion coefficients and molecular weights are presented.

TL;DR: A study of a discrete shimming scheme for NMR Mandhalas constructed from a set of individual magnet blocks indicates that imperfections of magnet blocks can lead to improved field homogeneity, and presents a new algorithm to improve the homogeneity of a permanent magnet assembly.