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We have developed an optical pumping NMR system for semiconductors as an effective nuclear spin polarizer for a solid-state NMR quantum computer. The system was successfully applied to enhance 31P nuclear spin polarization in InP doped with Fe, and the enhancement of the 31P NMR signal by more than two orders of magnitude was achieved. We also observed the strong dependences of the enhancement on the helicity and the photon energy of incident light. The most effective enhancement was achieved with the helicity σ+ and photon energy smaller than the bandgap by 10∼15 meV. [Copyright &y& Elsevier]

We have developed a 920-MHz NMR system and performed the proton NMR measurement of H2O and ethylbenzene using the superconducting magnet operating at 21.6 T (920 MHz for proton), which is the highest field produced by a superconducting NMR magnet in the persistent mode. From the NMR measurements, it is verified that both homogeneity and stability of the magnet have a specification sufficient for a high resolution NMR. [Copyright &y& Elsevier]

This study reports a first successful demonstration of a single channel proton 3D and 2D high-throughput ultrafast magic angle spinning (MAS) solid-state NMR techniques in an ultra-high magnetic field (1020 MHz) NMR spectrometer comprised of HTS/LTS magnet. High spectral resolution is well demonstrated. [ABSTRACT FROM AUTHOR]

We have successfully developed a 1020 MHz (24.0 T) NMR magnet, establishing the world’s highest magnetic field in high resolution NMR superconducting magnets. The magnet is a series connection of LTS (low- T c superconductors NbTi and Nb 3 Sn) outer coils and an HTS (high- T c superconductor, Bi-2223) innermost coil, being operated at superfluid liquid helium temperature such as around 1.8 K and in a driven-mode by an external DC power supply. The drift of the magnetic field was initially ± 0.8 ppm/10 h without the 2 H lock operation; it was then stabilized to be less than 1 ppb/10 h by using an NMR internal lock operation. The full-width at half maximum of a 1 H spectrum taken for 1% CHCl 3 in acetone-d 6 was as low as 0.7 Hz (0.7 ppb), which was sufficient for solution NMR. On the contrary, the temporal field stability under the external lock operation for solid-state NMR was 170 ppb/10 h, sufficient for NMR measurements for quadrupolar nuclei such as 17 O; a 17 O NMR measurement for labeled tri-peptide clearly demonstrated the effect of high magnetic field on solid-state NMR spectra. [ABSTRACT FROM AUTHOR]

Experimental and theoretical investigations of indium-115 electric-field-gradient (EFG) tensors of indium(III) oxide, In 2 O 3 , have been presented. Field-stepwise-swept QCPMG solid-state 115In NMR experiments are carried out at T ​= ​120 ​K, observed at 52.695 ​MHz, and in the range of external magnetic fields between 4.0 and 6.5 ​T. The spectral simulations yield the quadrupolar coupling constant, C Q value, of 183(2) MHz and the asymmetry parameter, η Q , of 0.05(5), for In(1), and that of 126(2) MHz and η Q of 0.86(5) for In(2). Quantum chemical calculations are carried out to provide 115In EFG tensor orientations with respect to the molecular structure. A relationship between operative frequencies and variable ranges of external magnetic fields is briefly discussed for field-swept solid-state 115In NMR. Image 1 [ABSTRACT FROM AUTHOR]

Alcohol drinking is a risk factor for cancer. The degree of risk is increased in subjects showing the flushing response, which is due to aldehyde dehydrogenase 2 (ALDH2) polymorphism. The attributable risk of alcohol drinking for cancer in Japan has not been sufficiently investigated with consideration of flushing response. We followed 78,825 Japanese in JPHC study cohort II. The association between alcohol consumption and cancer incidence was assessed according to self-reported flushing response using Cox proportional hazards regression models. The population-attributable fraction (PAF) of cancer incidence was also estimated. During 1993-2013 (average follow-up, 16.8 years), 8486 incident cancers (included 4386 alcohol-related cancers) were reported. Half of men and 36% of women had flushing response. In men with flushing response, moderate or higher alcohol drinking increased the risk of alcohol-related cancers compared with non-drinkers (150-299 g/week, HR 1.63, 95% CI, 1.43-1.99; 300-449 g/week, HR 2.02 95% CI, 1.67-2.44; ≥450 g/week, HR 1.75, 95% CI, 1.39-2.21). When flushing response was considered in comparisons between non-drinkers and non-flushers, non-flushing heavy drinkers had a slightly higher PAF than flushers (all cancers: flushers, 2.0% and non-flushers, 2.2%; alcohol-related cancers: flushers, 3.8% and non-flushers, 5.8%). Although the risk of alcohol-related cancer in men with flushing response increased with increasing alcohol consumption, heavy drinkers were also at high risk regardless of flushing response. Considering the PAF of alcohol consumption on cancer, efforts to discourage heavy alcohol consumption to reduce the incidence of alcohol-related cancers appear warranted regardless of flushing response. [ABSTRACT FROM AUTHOR]