Carrier Dynamics in a Series of Organic Magnetic Superconductors

Understanding how electrons behave, i.e., carrier dynamics, in superconductors is indispensable for understanding the mechanism of superconductivity. Recently we have reported the carrier dynamics of κ- and λ-(BETS)₂MCl₄ (BETS = bis(ethylenedithio)tetraselenafulvalene, M = Ga, Fe) based on ultrafast spectroscopy, but the interpretation of the results remains an open question. In this paper we interpreted the results with the aid of newly measured magnetic susceptibility, X-ray single crystal structural analysis, and band calculation. Observation of coherent phonons only in the λ-type salts indicated that <i>e</i>-ph interaction should be characteristically strong in the λ-type salts. By comparison of the observed carrier dynamics with a two-temperature model, the temperature-dependence of carrier dynamics is consistently explained by the different strengths of the <i>e</i>-ph interaction between the λ- and the κ-type salts. The difference in strength of the <i>e</i>-ph interactions is related to their crystal structures. In conclusion, their carrier dynamics is consistently interpreted and classified by their crystal structures

What Happens at the Interface between TTF and TCNQ Crystals (TTF = Tetrathiafulvalene and TCNQ = 7,7,8,8-Tetracyanoquinodimethane)?

The interface between tetrathiafulvalene (TTF) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) crystals was prepared by treating a TCNQ single crystal surface with TTF powder. Optical measurements and atomic force microscopy (AFM) observation of the interface indicated that not only are TTF–TCNQ nanocrystals formed at the interface, but also direct charge injection from TTF powder to the TCNQ single crystal surface may be responsible for the high conductivity of the interface

The Relationships between Metabolic Disorders (Hypertension, Dyslipidemia, and Impaired Glucose Tolerance) and Computed Tomography-Based Indices of Hepatic Steatosis or Visceral Fat Accumulation in Middle-Aged Japanese Men

<div><p>Background</p><p>Most studies on the relationships between metabolic disorders (hypertension, dyslipidemia, and impaired glucose tolerance) and hepatic steatosis (HS) or visceral fat accumulation (VFA) have been cross-sectional, and thus, these relationships remain unclear. We conducted a retrospective cohort study to clarify the relationships between components of metabolic disorders and HS/VFA.</p><p>Methods</p><p>The participants were 615 middle-aged men who were free from serious liver disorders, diabetes, and HS/VFA and underwent multiple general health check-ups at our institution between 2009 and 2013. The data from the initial and final check-ups were used. HS and VFA were assessed by computed tomography. HS was defined as a liver to spleen attenuation ratio of ≤1.0. VFA was defined as a visceral fat cross-sectional area of ≥100 cm² at the level of the navel. Metabolic disorders were defined using Japan’s metabolic syndrome diagnostic criteria. The participants were divided into four groups based on the presence (+) or absence (-) of HS/VFA. The onset rates of each metabolic disorder were compared among the four groups.</p><p>Results</p><p>Among the participants, 521, 55, 24, and 15 were classified as HS(-)/VFA(-), HS(-)/VFA(+), HS(+)/VFA(-), and HS(+)/VFA(+), respectively, at the end of the study. Impaired glucose tolerance was more common among the participants that exhibited HS or VFA (p = 0.05). On the other hand, dyslipidemia was more common among the participants that displayed VFA (p = 0.01).</p><p>Conclusions</p><p>It is likely that VFA is associated with impaired glucose tolerance and dyslipidemia, while HS might be associated with impaired glucose tolerance. Unfortunately, our study failed to detect associations between HS/VFA and metabolic disorders due to the low number of subjects that exhibited fat accumulation. Although our observational study had major limitations, we consider that it obtained some interesting results. HS and VFA might affect different metabolic disorders. Further large-scale longitudinal studies are needed to reveal the relationships between the components of metabolic disorders and HS/VFA.</p></div

Molecular Photoconductor with Simultaneously Photocontrollable Localized Spins

UV irradiation reversibly switches a new insulating and nonmagnetic molecular crystal, BPY­[Ni­(dmit)₂]₂ (BPY = <i>N</i>,<i>N</i>′-ethylene-2,2′-bipyridinium; Ni­(dmit)₂ = bis­(1,3-dithiole-2-thione-4,5-dithiolato)­nickelate­(III)), into a magnetic conductor. This is possible because the bipyridyl derivative cations (BPY²⁺) trigger a photochemical redox reaction in the crystal to produce a change of ∼10% in the filling of the Ni­(dmit)₂ valence band, leaving localized spins on the BPY themselves. In the dark, almost all of the BPY molecules are closed-shell cations, and most of the Ni­(dmit)₂ radical anions form spin-singlet pairs; thus, this material is a diamagnetic semiconductor. Under UV irradiation, a photocurrent is observed, which enhances the conductivity by 1 order of magnitude. Electron spin resonance measurements indicate that the UV irradiation reversibly generates carriers and localized spins on the Ni­(dmit)₂ and the BPY, respectively. This high photoconductivity can be explained by charge transfer (CT) transitions between Ni­(dmit)₂ and BPY in the UV region. In other words, the photoconduction and “photomagnetism” can be described as reversible optical control of the electronic states between an ionic salt (BPY²⁺/[Ni­(dmit)₂]⁻, nonmagnetic insulator) and a CT complex (BPY^2(1−δ)+/[Ni­(dmit)₂]^(1−δ)– (δ ≈ 0.1), magnetic conductor) in the solid state

Grouping of risk factors (excluding non-significant words).

Grouping of risk factors (excluding non-significant words).</p

Demographic characteristics according to Hepatic steatosis and Visceral fat accumulation.

<p>Demographic characteristics according to Hepatic steatosis and Visceral fat accumulation.</p

The relationships between hepatic steatosis / visceral fat accumulation and metabolic disorders.

<p>The relationships between hepatic steatosis / visceral fat accumulation and metabolic disorders.</p

The associations between hepatic steatosis / visceral fat accumulation and body mass index change / life style.

<p>The associations between hepatic steatosis / visceral fat accumulation and body mass index change / life style.</p

Demographic characteristics of the patients and nurse records.

Demographic characteristics of the patients and nurse records.</p

Flow diagram for the records included in this study.

Flow diagram for the records included in this study.</p