Spin injection and magnetoresistance in ferromagnet/superconductor/ferromagnet tunnel junctions

We theoretically study the spin-dependent transport in a ferromagnet/superconductor/ferro-magnet double barrier tunnel junction. The spin-polarized tunneling currents give rise to spin imbalance in the superconductor. The resulting nonequilibrium spin density suppresses the superconductivity with increase of the tunneling currents. We focus on the effect of asymmetry in the double tunnel junction, where the barrier height of the tunnel junction and the spin-polarization of the ferromagnets are different, on spin injection, and discuss how the superconductivity is suppressed in the asymmetric junction. Our results explain recent experimental results on the critical current suppression in high-$T_c$ SCs by spin injection.Comment: 3 pages, 2 figures, proceeding of MMM'9

Where did the super-small sized large bowel advanced cancer come from?

Our study suggested that the super-small sized (less than 15 mm in maximum diameter) large bowel advanced cancers, which were sometimes found, were derived from the superficial depressed-type or flat elevation-type of the colorectal early cancers, not polyp-type of those

A case of histoplasmosis Report 1. Cinical, mycological and pathological observations

In our country it has been believed that there is no histoplasmosis here in Japan. However, from the above clinical signs, radiological characteristics, laboratory tests, pathological and mycological examinations, and experimental findings, we believe this is the first case of histoplasmosis in Japan.</p

Plasma lipid profiling of different types of hepatic fibrosis induced by carbon tetrachloride and lomustine in rats

Supplementary tables. Table S1. Class, m/z, retention time, ion of detected and identified lipid molecules, and determined their fatty side chains. Table S2. Normalized levels of lipid molecules in individual samples. Table S3. Fold change and p-value of the levels of lipid molecules. (XLSX 317 kb

Nonequilibrium Kondo Effect in a Quantum Dot Coupled to Ferromagnetic Leads

We study the Kondo effect in the electron transport through a quantum dot coupled to ferromagnetic leads, using a real-time diagrammatic technique which provides a systematic description of the nonequilibrium dynamics of a system with strong local electron correlations. We evaluate the theory in an extension of the `resonant tunneling approximation', introduced earlier, by introducing the self-energy of the off-diagonal component of the reduced propagator in spin space. In this way we develop a charge and spin conserving approximation that accounts not only for Kondo correlations but also for the spin splitting and spin accumulation out of equilibrium. We show that the Kondo resonances, split by the applied bias voltage, may be spin polarized. A left-right asymmetry in the coupling strength and/or spin polarization of the electrodes significantly affects both the spin accumulation and the weight of the split Kondo resonances out of equilibrium. The effects are observable in the nonlinear differential conductance. We also discuss the influence of decoherence on the Kondo resonance in the frame of the real-time formulation.Comment: 13 pages, 13 figure

Ku-band long distance site-diversity (SD) Characteristics using new measuring system

Abstract—This paper deals with the short (10 km) and long dis-tance (300–1400 km) site-diversity (SD) characteristics by using a newly developed measuring system. In the proposed measuring system, six earth stations transmit 14-GHz band QPSK signals, and one measuring earth station receives 12-GHz band signals and processes them to determine SD characteristics. As a result, easy operation and maintenance, low-cost measuring system construc-tion and highly accurate data have been obtained. By comparing those measured results with the SD joint probability approxima-tion equation in ITU-R Rec.P.618-7, a good agreement can be ob-tained. Furthermore, the effect of typhoons on SD characteristics were measured. Index Terms—Rain attenuation, satellite communication system, site-diversity (SD) measurement system, SD characteristics, VSAT system design. I

Iridium-catalyzed α-selective deuteration of alcohols

新規重水素化触媒反応を開発 --医薬品への直接重水素導入を達成--. 京都大学プレスリリース. 2022-07-21.The development of chemoselective C(sp³)-H deuteration is of particular interest in synthetic chemistry. We herein report the α-selective, iridium(III)-bipyridonate-catalyzed hydrogen(H)/deuterium(D) isotope exchange of alcohols using deuterium oxide (D₂O) as the primary deuterium source. This method enables the direct, chemoselective deuteration of primary and secondary alcohols under basic or neutral conditions without being affected by coordinative functional groups such as imidazole and tetrazole. Successful substrates for deuterium labelling include the pharmaceuticals losartan potassium, rapidosept, guaifenesin, and diprophylline. The deuterated losartan potassium shows higher stability towards the metabolism by CYP2C9 than the protiated analogue. Kinetic and DFT studies indicate that the direct deuteration proceeds through dehydrogenation of alcohol to the carbonyl intermediate, conversion of [Ir[III]–H] to [Ir[III]−D] with D₂O, and deuteration of the carbonyl intermediate to give the α-deuterated product