We investigated the magnetic structure of the antiferromagnetic (AFM) ordered state (TN ∼ 34 K) in tetragonal UPt2Si2 using polarized and unpolarized neutron diffraction. Previous neutron scattering studies reported that this system possesses a simple AFM structure with a propagation vector, Q = 0, and the ordered magnetic moments aligned along the c-axis. By contrast, our latest resonant X-ray scattering (RXS) experiments have revealed that the magnetic structure is modulated by the charge-density-wave (CDW) order, which emerges in one of the two Pt atomic layers in the unit cell below ∼320 K. The modulation is characterized by a transverse wave in the c-plane, with the propagation vector of the CDW order, \(\boldsymbol{q}_{\text{CDW}} = ( {\sim} 0.42,0,0)\). In this study using neutron scattering, we observed that the superlattice reflections specified by qCDW develop below TN, in addition to the magnetic reflections with Q = 0, thereby further confirming the presence of modulation in the AFM structure of this system. From detailed analyses, we revealed that the amplitude of the transverse-wave magnetic modulation is 0.72(2) μB/U, which is quantitative information that can not be obtained through RXS experiments. This implies that the CDW drives the ordered magnetic moments to be tilted up to 20° in the AFM state. The observations strongly suggest that the magnetism of UPt2Si2 is heavily influenced by the hybridization effects between the 5f electrons of U and the 5d electrons of Pt.
Wind damage to coniferous plantation forests containing sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa) was studied in Japan. Wind conditions determined using an air flow simulation model, historical wind disturbance records and remote sensing measurements were integrated within a geographic information system (GIS). Based on the data set, the relationships between wind disturbances, wind speed and stand height were analyzed. A logistic analysis technique was applied to assess the probability of wind disturbance in stands that remained intact or were damaged as a result of the typhoon. The results indicate that higher wind speeds and greater stand heights increase the probability of wind disturbance in both sugi and hinoki plantation forests. The logistic regression model enabled us to predict the likelihood of wind disturbance at our study site. Our results confirmed that it is possible, using wind condition prediction software, to analyse wind disturbance in sugi and hinoki plantation forests.
Abstract Background Circulating autotaxin (ATX) levels have been reported to correlate with liver inflammation activity and liver fibrosis severity in patients with non-alcoholic fatty liver disease (NAFLD). The objective of this study was to investigate whether serum ATX could predict liver-related events (LRE) in NAFLD patients. Methods This retrospective investigation included 309 biopsy-proven NAFLD patients registered at Shinshu University Hospital between 1998 and 2021. All patients were followed for at least 1 year, during which time the prevalence of LRE, including newly developing hepatocellular carcinoma, hepatic encephalopathy, ascites, and esophagogastric varices, was investigated in relation to ATX levels at the time of liver biopsy. Results During the median follow-up period of 7.0 years, LRE were observed in 20 patients (6.5%). The area under the receiver operating characteristic curve and cut-off value of serum ATX for predicting LRE were 0.81 and 1.227 mg/L, respectively. Patients with serum ATX greater than the cut-off at the time of liver biopsy had a significantly higher cumulative incidence of LRE than those without (18.4% vs. 2.7%, p < 0.00001). Multivariate Cox proportional hazards models for LRE determined fibrosis stage and ATX divided by the upper limit of normal as independently associated factors. Conclusion Serum ATX may serve as a predictive marker for LRE in patients with NAFLD.
We have investigated anomalously slow magnetic domain growth in an antiferromagnetic (AF) phase of isosceles triangular lattice Ising antiferromagnets ${\mathrm{Co}}_{1\ensuremath{-}x}{\mathrm{Mg}}_{x}{\mathrm{Nb}}_{2}{\mathrm{O}}_{6}$ with $x=0$ and 0.004, by means of time-resolved neutron diffraction measurements. Applying the multi-profile-deconvolution analysis to the observed diffraction profiles, we have revealed that time evolutions of spin correlation lengths along the $a$ and $b$ axes, ${\ensuremath{\xi}}_{a}$ and ${\ensuremath{\xi}}_{b}$, are well described by a power-law scaling form of ${\ensuremath{\xi}}_{0\ensuremath{\alpha}}+{L}_{\ensuremath{\alpha}}{(t/{\ensuremath{\tau}}_{\ensuremath{\alpha}})}^{n}$ $(\ensuremath{\alpha}=a,b)$ with a universal growth exponent of $n=0.2$. The characteristic time scale of the domain growth, ${\ensuremath{\tau}}_{\ensuremath{\alpha}}$, was found to exhibit Arrhenius-type temperature dependence in the AF phase. A comparison between the results of the $x=0$ and 0.004 samples has revealed that the nonmagnetic substitution significantly reduces the initial correlation length, ${\ensuremath{\xi}}_{0\ensuremath{\alpha}}$, and the activation energy in the Arrhenius-type temperature dependence of ${\ensuremath{\tau}}_{\ensuremath{\alpha}}$. We have also found that magnetic domain growth in a magnetic-field-induced ferrimagnetic phase also follows the power law with the growth exponent of $n=0.2$. On the basis of these results, we have concluded that the existence of ferromagnetic Ising spin chains running along the $c$ axis and the geometrical spin frustration in the $ab$ plane are the keys to the domain growth kinetics in this system. The former and the latter govern the characteristic time scale and the growth exponent, respectively.
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
