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We have measured 13C-NMR and reflection spectrum in κ-(BEDTTTF)2 Ag(CN)2·H2O. No increase of the AF magnetic fluctuation as in κ-(BEDT-TTF)2Cu[N(CN)2]C was observed. Results of 13C-NMR suggested the emergence of superconductivity does not require the increase of the AF magnetic fluctuation, but a crossover to the Fermi liquid regime. Optical studies suggested the crossover corresponds to the development of the coherence of conduction electrons.

Little is known about the acquisition of intubation skills among novice physicians during their one-year clinical training. Our primary objective was to determine the changes in the intubation skills of novice physicians between prior to the clinical training and after completion of the clinical training. We used data of a prospective longitudinal multicenter data registry developed to investigate factors associated with the improvement of intubation skills among novice physicians. The study participants included 90 postgraduate year 1 physicians in 2015–2016. We used 4 simulation scenarios based on the devices used (direct laryngoscope [DL] and Airway scope [AWS]) and difficulty of intubation (normal and difficult scenarios). As a marker of the intubation skills, we used the force applied on the maxillary incisors and the tongue with each intubation. We compared the data obtained prior to clinical training with those obtained after completion of one-year clinical training. When using DL, compared to prior, significantly less force were applied on the maxillary incisors and the tongue after clinical training in the normal scenario (28.0 N vs 19.5 N, p < 0.001, and 11.1 N vs 8.4 N, p = 0.004). Likewise, when using AWS, compared to prior, significantly less force were applied on the tongue after clinical training in the normal scenario (22.0 N vs 0 N, p < 0.001). The force on the tongue decreased after clinical training but not significant. These associations persisted in the difficult airway scenario. These findings suggest that force applied on oral structures can be quantified as a marker of intubation skills by using high-fidelity simulators, and the assessment of procedural competency is recommended for all novice physicians prior to performing intubation in the clinical setting to improve the quality of emergency care.

κ-(BEDT-TTF) 2 X salts show the variety physical properties from the superconductivity to the magnetic ordering. It is important to investigate the characters of κ-(BEDT-TTF) 2 X from microscopic probes, systematically. 13 C-NMR is a one of the most powerful tool for this aim. In order to study the variety physical properties on of κ-(BEDT-TTF) 2 X, We performed single crystal 13 C-NMR works on deuterized samples, alloy system etc. Here we report especially about κ-(BEDT-TTF) 2 Cu 2 (CN) 3 from our a several approaches in this proceedings. Recently, for κ-(BEDT-TTF) 2 Cu 2 (CN) 3 , the magnetic frustrations are pointed out. However, we found the evidence of the electron localization phenomenon on this salt from 13 C-NMR work.

In order to investigate the nature of the insulator phase of $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}{\mathrm{Cu}}_{2}{(\mathrm{C}\mathrm{N})}_{3}$ [where BEDT-TTF represents bis(ethylenedithio)terathiofulvalene] and why this salt is a superconductor under pressure but not under ambient pressure, we examined the $^{13}\mathrm{C}$ NMR spectra and spin lattice relaxation rate of $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}{\mathrm{Cu}}_{2}{(\mathrm{C}\mathrm{N})}_{3}$ under pressure. The spin susceptibility evaluated from the Knight shift decreased with increase in pressure, and line broadening was suppressed above a critical pressure. The temperature dependence of ${({T}_{1}T)}^{\ensuremath{-}1}$ for $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}{\mathrm{Cu}}_{2}{(\mathrm{C}\mathrm{N})}_{3}$ above a critical pressure was that for $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}X$, where $X$ was $\mathrm{Cu}[\mathrm{N}{(\mathrm{C}\mathrm{N})}_{2}]\mathrm{Br}$ or $\mathrm{Cu}{(\mathrm{N}\mathrm{C}\mathrm{S})}_{2}$. These results suggest that the electronic structure of $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}{\mathrm{Cu}}_{2}{(\mathrm{C}\mathrm{N})}_{3}$ under pressure is similar to that of other $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}X$ salts. The results support our model that electron inhomogeneity and hopping conduction, which are common features of semiconductivity in $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}X$ at high temperatures, are responsible for the insulator phase in $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}{\mathrm{Cu}}_{2}{(\mathrm{C}\mathrm{N})}_{3}$. The electron inhomogeneity suppresses the semiconductor-metal transformation and superconductivity observed in other $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}X$ salts.

$\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}X$ salts exhibit a wide range of properties from superconductivity to magnetic ordering. The phase diagram of this system has been understood as the competition between anti-ferromagnetic insulating behavior and superconductivity. The $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}X$ system has been well explained using a parameter, U/W, as well as the high ${T}_{c}$ cuprates. $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}{\mathrm{Cu}}_{2}{(\mathrm{CN})}_{3}$, however, behaved as an insulator without magnetic ordering. This salt cannot be described by the phase diagram described by the competition between superconductivity and magnetism. It is interesting to explore the nature of this insulating phase with an eye toward understanding the universal phase diagram of the $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}X$ system. Magnetic frustration due to the triangular spin lattice has recently been reported for $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}{\mathrm{Cu}}_{2}{(\mathrm{CN})}_{3}$ from $^{1}\mathrm{H}$-nuclear magnetic resonance (NMR) study. To investigate the insulating properties of this salt, we characterized it using $^{13}\mathrm{C}\text{\ensuremath{-}}\mathrm{NMR}$. In contrast to previous $^{1}\mathrm{H}\text{\ensuremath{-}}\mathrm{NMR}$ studies, at low temperatures, we observed line broadenings that were proportional to the hyperfine coupling constants, which suggested inhomogeous electron localization. We also observed antiferromagnetic fluctuations which, as is the case with other salts, intensified with decreasing temperature. To understand the electronic properties of $\ensuremath{\kappa}\text{\ensuremath{-}}{(\mathrm{BEDT}\text{\ensuremath{-}}\mathrm{TTF})}_{2}X$ system, in addition to the U/W, the electron localization effect from the relatively narrow bandwidth is important.

A new anti‐HIV agent 4′‐cyano‐2′,3′‐didehydro‐3′‐deoxythymidine (9) was synthesized by allylic substitution of the 3′,4′‐unsaturated nucleoside 14, having a leaving group at the 2′‐position, with cyanotrimethylsilane in the presence of SnCl4. Evaluation of the anti‐HIV activity of 9 showed that this compound is much less potent than the recently reported 2′,3′‐didehydro‐3′‐deoxy‐4′‐(ethynyl)thymidine (1).