Van Vleck paramagnetism of the thulium garnet Tm3Al5O12

The magnetic susceptibility of the garnet-type single crystal Tm3Al5O12 exhibits the typical Van Vleck temperature independent paramagnetism below ≈8 K. The temperature dependence of the susceptibility over the range 2.0–300 K has been analyzed on the assumption that the cubic crystal-electric-field dominates the energy level on 3H6 (J=6) ground multiplet for Tm3+ ion having 12-electrons in 4f shell. The ground state of the 3H6is nonmagnetic with Γ2 singlet, avoiding the Kramers doublet. The energy separation between Γ2 and the first excited state Γ(2)5 triplet is evaluated to be 68.0 K. The whole energy interval Δ between Γ2 and the highest state Γ1 in 3H6 is estimated to be 339.5 K

Ferromagnetism and the metal-insulator transition in the thiospinel Cu(Ir1-xCrx)2S4

A thiospinel CuIr2S4 exhibits a temperature-induced metal-insulator (M-I) transition at 230 K with a simultaneous spin-dimerization and charge-ordering transition although a three-dimensional system. On the other hand, CuCr2S4 has the same spinel structure without any structural transformations. CuCr2S4 remains metallic and is ferromagnetic with the Curie temperature TC≃377 K. In order to see the effect of substituting Cr for Ir on the M-I transition, we have carried out a systematic experimental study of electrical and magnetic properties of Cu(Ir1-xCrx)2S4 system. The M-I transition temperature decreases steeply with increasing Cr-composition x and this transition is not detected above x≃0.05. The value of TC decreases with decreasing x from 1.0, then TC disappears below x≃0.20. The ferromagnetic state suggests the non-collinear spin alignment. In the intermediate composition range over x=0.08 to 0.20, the B-site undergoes a local crystal distortion around 180 K, where the energy level t2g splits into lower symmetry. Then the low-spin state within the t2g subspace is realized for Cr3+ ion with s=1/2. The magnetic state of Cr3+ ion indicates a crossover from high temperature s=3/2 to low temperature s=1/2 state around 180 K

Photoemission and band-calculation studies of the charge-density wave in CuV2S4

We have studied the electronic structure and its changes across the charge-density-wave (CDW) transition in spinel-type CuV2S4 by photoemission spectroscopy and first-principles band-structure calculations. The photoemission spectra show pseudogap-like behavior and the gap size is estimated to be ~90 meV. The large energy scale of the pseudogap compared to the transition temperature and its anomalous temperature dependence implies that the involved interaction is in the strong-coupling regime. The calculated electronic susceptibility χ(q) shows a small peak at q≃11/40[110], which is consistent with the observed wave vector q≃¼[110] characterizing the CDW. This result suggests that Fermi surface nesting is at least partly responsible for the CDW formatio

Metal-insulator transition and superconductivity in the spinel-type Cu(Ir1-xRhx)2S4 system

The normal thiospinel CuIr2S4 exhibits a temperature-induced metal-insulator (M-I) transition around 226 K with structural transformation, showing hysteresis on heating and cooling. It has been verified that d electrons of Ir atom on the octahedral B sites have a significant role for the M-I transition. On the other hand, CuRh2S4 is a superconductor with the transition temperature Tc=4.70 K, which is well understood on the basis of the BCS theory. It is important to investigate the effect on the M-I transition by substitution of Rh for Ir. We have systematically studied structural transformation and electrical and magnetic properties of Cu(Ir1-xRhx)2S4. The features of the M-I transition change with Rh concentration x. A phase diagram of temperature versus x will be proposed for the Cu(Ir1-xRhx)2S4 system. The sharp M-I transition temperature varies drastically from 226 to 93 K with x from 0.00 to 0.17 and disappears around x=0.20. In a region of 0.00⩽x⩽0.20, the magnetic susceptibility begins decreasing at a constant onset temperature 226 K on cooling process and shows rather broad temperature variation, even though the metallic state is kept in the resistivity. The sharp M-I transition can take place after the suppression of magnitude in the susceptibility has sufficiently developed far below 226 K. These experimental results are discussed with emphasis on the intrinsic difference between Cu(Ir1-xRhx)2S4 and CuIr2(S1-xSex)4 systems. Furthermore, we will mention the superconductivity for both systems of Cu(Ir1-xRhx)2S4 with high-Rh concentration region and Cu1-xNixRh2S

Investigation of the Utility and Safety of Dynamic Computed Tomography with Vasodilators

Background: Dynamic computed tomography (CT) angiography is useful for evaluating of hepatic vascularity. Although vasodilators increase hepatic blood flow, the utility of dynamic CT with vasodilators is unclear. Here we investigated the utility and safety of dynamic CT with vasodilators. Methods: A prospective case-control radiographic evaluation using abdominal dynamic CT with and without vasodilator was performed at a single center between October 2015 and September 2016. We compared the CT values in Hounsfield units of the aorta; celiac artery; and common, right, and left hepatic arteries in the arterial phase and the main trunk; right and left branches of the portal vein; and right, middle, and left hepatic veins in the portal phase with and without vasodilators. The region of interest was set in each element of the liver vasculature. Four radiological technologists independently and visually compared the scores of the portal vein (P-score) and hepatic vein (V-score) on a 5-point scale with and without vasodilators. Results: The CT values of arteries and veins using vasodilators were significantly higher than those without vasodilators. With and without vasodilators, the P-scores were 3.1 ± 1.2 and 4.0 ± 1.1 (P < 0.05) and the V-scores were 3.3 ± 1.4 and 4.3 ± 1.0 (P < 0.05). Only one patient with vasodilator use had transient hypotension and recovered immediately without medication. Conclusion: Dynamic CT with vasodilators can provides better visualization of vascular structures

Metal-insulator transition in the spinel-type Cu1-xNixIr2S4 system

The normal thiospinel CuIr2S4 exhibits a temperature-induced metal-insulator (M-I) transition around 230 K with structural transformation, showing hysteresis on heating and cooling. The symmetry changes from a high-temperature cubic phase in a metallic state to low-temperature tetragonal phase in an insulating state. A significant characteristic feature is the absence of localized magnetic moment below TM-I. On the other hand, NiIr2S4 remains metallic down to 4.2 K without the structural transformation. We have systematically studied the structural transformation and electrical and magnetic properties of Cu1-xNixIr2S4. The variation of the metal-insulator transition with Ni concentration x is presented. A phase diagram between TM-I and x will be provided for the Cu1-xNixIr2S4 system. The TM-I varies drastically from 226 to 88 K with x from 0.00 to 0.13 and disappears around x=0.15. For 0.08&les;x&les;0.13, the cubic and tetragonal phases coexist below TM-I. For a high-temperature metallic phase, the value of the Pauli paramagnetic susceptibility increases monotonically with x, which shows dD(&epsiv;)/d&epsiv;<0 at the Fermi energy &epsiv;F, through the decrease of the free-electron number density, where D(&epsiv;) is the electronic density-of-state on the basis of a nearly free-electron model. By the introduction of a Ni ion to the A-site of CuIr2S4 in the spinel structure, whether the localized magnetic moment below TM-I arises or not will be discusse

Conformal Anomaly in 4D Gravity-Matter Theories Non-minimally Coupled with Dilaton

The conformal anomaly for 4D gravity-matter theories, which are non-minimally coupled with the dilaton, is systematically studied. Special care is taken for: rescaling of fields, treatment of total derivatives, hermiticity of the system operator and choice of measure. Scalar, spinor and vector fields are taken as the matter quantum fields and their explicit conformal anomalies in the gravity-dilaton background are found. The cohomology analysis is done and some new conformal invariants and trivial terms, involving the dilaton, are obtained. The symmetry of the constant shift of the dilaton field plays an important role. The general structure of the conformal anomaly is examined. It is shown that the dilaton affects the conformal anomaly characteristically for each case: 1)[Scalar] The dilaton changes the conformal anomaly only by a new conformal invariant, $I_4$; 2)[Spinor] The dilaton does {\it not} change the conformal anomaly; 3)[Vector] The dilaton changes the conformal anomaly by three new (generalized) conformal invariants, $I_4,I_2,I_{1}$. We present some new anomaly formulae which are useful for practical calculations. Finally, the anomaly induced action is calculated for the dilatonic Wess-Zumino model. We point out that the coefficient of the total derivative term in the conformal anomaly for the 2D scalar coupled to a dilaton is ambiguous. This resolves the disagreement between calculations in refs.\cite{ENO,NO,SI97,KLV} and the result of Hawking-Bousso\cite{BH}.Comment: 37 pages, Latex, No figur

Peripheral Blood CD64 Levels Decrease in Crohn's Disease following Granulocyte and Monocyte Adsorptive Apheresis

Granulocyte and monocyte adsorptive apheresis (GMA) is reportedly useful as induction therapy for Crohn's disease (CD). However, the effects of GMA on CD64 have not been well characterized. We report here our assessment of CD64 expression on neutrophils before and after treatment with GMA in two patients with CD. The severity of CD was assessed with the CD activity index (CDAI). The duration of each GMA session was 60 min at a flow rate of 30 ml/min as per protocol. CD64 expression on neutrophils was measured by analyzing whole blood with a FACScan flow cytometer. In case 1, CD64 levels after each session of GMA tended to decrease compared to pretreatment levels, whereas in case 2, CD64 levels dropped significantly after treatment. The CDAI decreased after GMA in both cases 1 and 2. A significant correlation was noted between CDAI scores and CD64 levels in both cases. In conclusion, GMA reduced blood CD64 levels, which would be an important factor for the decrease of CDAI scores

Thymus and Activation-regulated Chemokine as a Biomarker for IgG4-related Disease

High serum concentrations of thymus and activation-regulated chemokine (TARC) are observed in allergic diseases such as atopic dermatitis and bronchial asthma. Frequent allergic symptoms have been reported in patients with IgG4-related disease (IgG4-RD). We investigated the pathogenic role of TARC as a biomarker in IgG4-RD patients. We evaluated the serum concentrations of TARC from 29 IgG4-RD patients, 28 primary Sjogren syndrome (pSS) patients, and 23 healthy controls (HCs) by enzyme-linked immunosorbent assay (ELISA). We analyzed the correlations between the TARC concentrations and the subjects’ clinical parameters. To investigate the biological effect of TARC on the pathogenesis of IgG4-RD, we evaluated the in vitro induction of plasmablasts from IgG4-RD patients by TARC. The serum concentrations of TARC in the IgG4-RD patients were significantly higher than those of the pSS patients and HCs. The serum TARC concentration of the IgG4-RD group was positively correlated with the IgG4-RD responder index (IgG4-RD RI) score and with the number of organs involved, but it was not correlated with the serum IgG4 level or eosinophil number in the IgG4-RD patients’ peripheral blood. The patients who had lung involvement had higher serum TARC concentrations. In vitro, TARC clearly induced the formation of plasmablasts from the IgG4-RD patients’ peripheral blood mononuclear cells. Collectively, our data suggest that a systemic increment of TARC may contribute to the development of IgG4-RD through an aberrant induction of plasmablasts

Granulocyte-macrophage colony-stimulating factor and tumor necrosis factor-α in combination is a useful diagnostic biomarker to distinguish familial Mediterranean fever from sepsis

Objective: To identify potential biomarkers to distinguish familial Mediterranean fever (FMF) from sepsis.Method: We recruited 28 patients diagnosed with typical FMF (according to the Tel Hashomer criteria), 22 patients with sepsis, and 118 age-matched controls. Serum levels of 40 cytokines were analyzed using multi-suspension cytokine array. We performed a cluster analysis of each cytokine in the FMF and sepsis groups in order to identify specific molecular networks. Multivariate classification (random forest analysis) and logistic regression analysis were used to rank the cytokines by importance and determine specific biomarkers for distinguishing FMF from sepsis.Results: Fifteen of the 40 cytokines were found to be suitable for further analysis. Levels of serum granulocyte-macrophage colony-stimulating factor (GM-CSF), fibroblast growth factor 2, vascular endothelial growth factor, macrophage inflammatory protein-1b, and interleukin-17 were significantly elevated, whereas tumor necrosis factor-α (TNF-α) was significantly lower in patients with FMF compared with those with sepsis. Cytokine clustering patterns differed between the two groups. Multivariate classification followed by logistic regression analysis revealed that measurement of both GM-CSF and TNF-α could distinguish FMF from sepsis with high accuracy (cut-off values for GM-CSF = 8.3 pg/mL; TNF-α = 16.3 pg/mL; sensitivity, 92.9%; specificity, 94.4%; accuracy, 93.4%).Conclusion: Determination of GM-CSF and TNF-α levels in combination may represent a biomarker for the differential diagnosis of FMF from sepsis, based on measurement of multiple cytokines