Electron-decoupled MAS DNP with N@C.

Frequency-chirped microwaves decouple electron- and C-spins in magic-angle spinning N@C:C powder, improving DNP-enhanced C NMR signal intensity by 12% for 7 s polarization, and 5% for 30 s polarization. This electron decoupling demonstration is a step toward utilizing N@C as a controllable electron-spin source for magic-angle spinning magnetic resonance experiments.

Neurophysiological patterns of acute and post-acute foodborne botulism.

Introduction/aims: Neurophysiological patterns in patients with foodborne botulism are rarely described after the acute phase. We report data from a large Italian outbreak of botulism, with patients evaluated at different timepoints after poisoning.

Methods: Eighteen male patients (mean age 47 ± 8.

Describing angular momentum conventions in circularly polarized optically pumped NMR in GaAs and CdTe.

The physical phenomena governing hyperpolarization through optical pumping of conduction electrons continue to be explored in multiple semiconductor systems. One early finding has been the asymmetry between the optically pumped nuclear magnetic resonance (OPNMR) signals when generated by different circular polarizations (i.e.

In Situ Detection of Endogenous HIV Activation by Dynamic Nuclear Polarization NMR and Flow Cytometry.

We demonstrate for the first time in-cell dynamic nuclear polarization (DNP) in conjunction with flow cytometry sorting to address the cellular heterogeneity of in-cell samples. Utilizing a green fluorescent protein (GFP) reporter of HIV reactivation, we correlate increased N resonance intensity with cytokine-driven HIV reactivation in a human cell line model of HIV latency. As few as 10% GFP+ cells could be detected by DNP nuclear magnetic resonance (NMR).

Characterization of frequency-chirped dynamic nuclear polarization in rotating solids.

Continuous wave (CW) dynamic nuclear polarization (DNP) is used with magic angle spinning (MAS) to enhance the typically poor sensitivity of nuclear magnetic resonance (NMR) by orders of magnitude. In a recent publication we show that further enhancement is obtained by using a frequency-agile gyrotron to chirp incident microwave frequency through the electron resonance frequency during DNP transfer. Here we characterize the effect of chirped MAS DNP by investigating the sweep time, sweep width, center-frequency, and electron Rabi frequency of the chirps.