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High-field phase diagram of a chiral-lattice antiferromagnet Sr(TiO)Cu4(PO4)4 is studied by means of the ultrasound, dielectric, and magnetocaloric-effect measurements. These experimental techniques reveal two new phase transitions at high fields, which have not been resolved by the previous magnetization experiments. Specifically, the c66 acoustic mode shows drastic changes with hysteresis with applied fields along the c axis, indicating a strong magneto-elastic coupling. Combined with the cluster mean-field theory, we discuss the origins of these phase transitions. By considering the chiral-twist effect of Cu4O12 cupola units, which is inherent to the chiral crystal structure, the phase diagram is reasonably reproduced. The agreement between the experiment and theory suggests that this material is a unique quasi two-dimensional spin system with competing exchange interactions and chirality, leading to the rich phase diagram., Comment: 12 pages, 11 figures, 1 table

In this study, we have performed the magnetocaloric effect and the specific heat measurements of chromium spinel oxide HgCr$_2$O$_4$, wherein the magnetic Cr$^{3+}$ ions form a highly frustrated pyrochlore lattice with significant spin-lattice coupling. In addition to the known magnetic-field-induced phases, our thermodynamic measurements detect a novel quantum phase just before the saturation of the magnetization, which has not been expected from the classical theories of the pyrochlore lattice antiferromagnet with spin-lattice coupling. Based on recent theoretical model calculation, we discuss the possibility of a spin nematic state appearing for this quantum phase., 14 pages, 4 figures

We study nonreciprocal directional dichroism (NDD) of magnetoelectric Pb(TiO)Cu4(PO4)4 in magnetic fields up to 49 T via magneto-optical spectroscopy in the (near-)visible range. Measuring the opti...

Three dimensionally curved graphene with a wide range of curvature radii from 25 nm to 1000 nm demonstrates that nano-scale curvature is a new degree of freedom to tune the transport properties of graphene by manipulating 2D electron kinetics on 3D curved surfaces.

In this study, we conducted various magnetotransport measurements on Fe$_{1+y}$Te$_{1-x}$Se$_{x}$ single crystals from which excess iron was sufficiently removed. Our results revealed that crossover from the incoherent to the coherent electronic state and opening of the pseudogap occur at high temperatures ($\approx$ 150 K for $x$ = 0.2). This is accompanied by a more substantial pseudogap and the emergence of a phase with a multi-band nature at lower temperatures (below $\approx$ 50 K for $x$ = 0.2) before superconductivity sets in. A comparison of these results with those of the as-grown (non-superconducting) samples implies that the coherent state accompanied by the pseudogap is needed for the occurrence of superconductivity in this system., 9 pages, 7 figures

Magnetic-field effect on the magnetic and electric properties in a chiral polar ordered corundum Ni$_2$InSbO$_6$ has been investigated. Single-crystal soft x-ray and neutron diffraction measurements confirm long-wavelength magnetic modulation. The modulation direction tends to align along the magnetic field applied perpendicular to the polar axis, suggesting that the nearly proper-screw type helicoid should be formed below 77\,K. The application of a high magnetic field causes a metamagnetic transition. In a magnetic field applied perpendicular to the polar axis, a helix-to-canted antiferromagnetic transition takes place through the intermediate soliton lattice type state. On the other hand, a magnetic field applied along the polar axis induces a first-order metamagnetic transition. These metamagnetic transitions accompany a change in the electric polarization along the polar axis.

We report our combined experimental and theoretical study of magnetoelectric properties of an antiferromagnet Sr(TiO)Cu$_4$(PO$_4$)$_4$, in comparison with the isostructurals Ba(TiO)Cu$_4$(PO$_4$)$_4$ and Pb(TiO)Cu$_4$(PO$_4$)$_4$. The family of compounds commonly possesses a low-symmetric magnetic unit called the square cupola, which is a source of magnetoelectric responses associated with the magnetic multipoles activated under simultaneous breaking of spatial inversion and time reversal symmetries. Measuring the full magnetization curves and the magnetic-field profiles of dielectric constant for Sr(TiO)Cu$_4$(PO$_4$)$_4$ and comparing them with the theoretical analyses by the cluster mean-field theory, we find that the effective $S=1/2$ spin model, which was used for the previous studies for Ba(TiO)Cu$_4$(PO$_4$)$_4$ and Pb(TiO)Cu$_4$(PO$_4$)$_4$, well explains the experimental results by tuning the model parameters. Furthermore, elaborating the phase diagram of the model, we find that the square cupolas could host a variety of magnetic multipoles, i.e., monopole, toroidal moment, and quadrupole tensor, depending on the parameters that could be modulated by deformations of the magnetic square cupolas. Our results not only provide a microscopic understanding of the series of the square cupola compounds, but also stimulate further exploration of the magnetoelectric behavior arising from cluster multipoles harboring in low-symmetric magnetic units., Comment: 13 pages, 12 figures

To elucidate the pseudogap phase diagram including the overdoped state of high transition temperature (high-$T_c$) cuprates, we must understand the origin of the positive out-of-plane magnetoconductivity (MC) observed in these compounds. For this purpose, the out-of-plane resistivity $\rho_c(T,H)$ of an overdoped Bi$_{1.6}$Pb$_{0.4}$Sr$_{2}$CaCu$_{1.96}$Fe$_{0.04}$O$_{8+\delta}$ (Bi-2212) single crystal is measured under pulsed magnetic fields up to 60 T. We show that the superconductive density-of-states (DOS) depletion effect, in addition to the pseudogap effect, clearly appears below the superconductive fluctuation regime, and the contribution becomes dominant in the superconducting state., Comment: 6 pages, 5 figures

To elucidate the pseudogap phase diagram including the overdoped state of high transition temperature (high-$T_c$) cuprates, we must understand the origin of the positive out-of-plane magnetoconductivity (MC) observed in these compounds. For this purpose, the out-of-plane resistivity $��_c(T,H)$ of an overdoped Bi$_{1.6}$Pb$_{0.4}$Sr$_{2}$CaCu$_{1.96}$Fe$_{0.04}$O$_{8+��}$ (Bi-2212) single crystal is measured under pulsed magnetic fields up to 60 T. We show that the superconductive density-of-states (DOS) depletion effect, in addition to the pseudogap effect, clearly appears below the superconductive fluctuation regime, and the contribution becomes dominant in the superconducting state., 6 pages, 5 figures

To investigate the relationship between the pseudogap and superconductivity, we measured both the in-plane ($��_{ab}$) and out-of-plane ($��_c$) resistivity for oxygen-controlled Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+��}$ single crystals subject to magnetic fields (parallel to the $c$ axis) of up to 17.5 T. The onset temperature for the superconductive fluctuation, $T_{scf}$, is determined by the large positive in-plane magnetoresistance (MR) and negative out-of-plane MR observed near $T_c$, whereas the pseudogap opening temperature $T^*$ is determined by the semiconductive upturn of the zero-field $��_c$. $T_{scf}$ was found to scale roughly as $T_c$, with a decreasing temperature interval between them upon doping. On the other hand, $T^*$ starts out much higher than $T_{scf}$ but decreases monotonically upon doping; finally, at a heavily overdoped state, it is not observed above $T_{scf}$. These results imply that the pseudogap is not a simple precursor of superconductivity, but that further study is needed to determine whether or not $T^*$ exists below $T_{scf}$ in the heavily overdoped state., 17 pages, 7 figures, to appear in JPSJ

Magnetization and electrical resistivity measurements were carried out for polycrystalline Mn_{2}Sb_{1-x}Ge_{x} (0.05 ≤ x ≤ 0.2) and Mn_{2}Sb_{1-x}Sn_{x} (0.08 ≤ x ≤ 0.15) in magnetic fields up to 16 T in the 4.2–600 K temperature range in order to investigate the magnetic and the electrical properties under magnetic fields. Mn_{2}Sb_{0.95}Ge_{0.05} and Mn_{2}Sb_{0.9}Sn_{0.1} showed a first-order magnetic transition from a ferrimagnetic (FRI) to an antiferromagnetic (AFM) phase in the vicinity of T_{t} = 172 K and 190 K, respectively, with decreasing temperature in a zero magnetic field. With increasing x, T_{C} decreased slightly and T_{t} increased. The electrical resistivity changes abruptly by 87% for Mn_{2}Sb_{0.95}Ge_{0.05} and 43% for Mn_{2}Sb_{0.9}Sn_{0.1} at T_{t}. The magnetic phase diagrams of Mn_{2}Sb_{1-x}Ge_{x} and Mn_{2}Sb_{1-x}Sn_{x} are presented.

We have studied the effects of Saiboku-to, a traditional Chinese medicine having suppressive activities for leukotriene production and release, on the proliferation of the estrogen-responsive mouse Leydig tumor cell line B-1F. In our previous reports, it is shown that Saiboku-to promotes, but Scutellaria baicalensis, one of the components (herbs) of Saiboku-to, significantly inhibits the proliferation of B-1F cells in vitro and in vivo, and induces DNA fragmentation and morphological changes such as nuclear aggregation and fragmentation. In this study, we examined telomerase activity, cell cycle, polyunsaturated fatty acid metabolism and expression of nuclear factor κB (NF-κB) in order to determine the mechanism of growth inhibition in B-1F cells treated with Scutellaria baicalensis. Telomerase activity was decreased in a dose-dependent manner in treated B-1F cells. Cellular populations in the sub-G0/G1 and G2/M phases were increased, but those in M phase had no change. Although cyclin D1 mRNA was highly expressed in the presence of estradiol (E2), cyclin A and E mRNA levels did not significantly change. When B-1F cells were treated with Scutellaria baicalensis, expression of cyclin D1 was suppressed and that of p21 was inversely increased. Moreover, Scutellaria baicalensis influenced arachidonic and linoleic acid metabolism, and increased production of 13(S)-HODE. In the presence of E2 Scutellaria baicalensis decreased expression of NF-κB p65 to 0.71-fold in B-1F cells. These results show that Scutellaria baicalensis might induce cell cycle arrest at G1 phase and apoptosis via inhibition of telomerase activity, changes of enzymatic activities in polyunsaturated fatty acid metabolism and suppression of NF-κB.

We have demonstrated that the proliferation of estrogen-responsive mouse Leydig tumor cell line B-1F is induced via suppression of 5-lipoxygenase activity followed by decrease of leukotrienes (LTs). Additionally, it has been reported that LTD4 induces apoptosis in B-1F cells. In this study, we examined effects of Saiboku-to, a traditional Chinese medicine having suppressive activities for LT production and release, on the proliferation. Saiboku-to promoted, but Scutellaria baicalensis, one of components (herbs) of Saiboku-to, significantly inhibited the proliferation of B-1F cells in vitro and in vivo. The action of Scutellaria baicalensis in B-1F cells was studied in more detail. Although Scutellaria baicalensis consists of flavonoids, iridoids, volatile oils and others, it and its major constituents had no direct effect on estrogen binding sites in B-1F cells. B-1F cells treated with Scutellaria baicalensis showed morphological changes such as nuclear aggregation and fragmentation. DNA fragmentation was also observed, indicating that Scutellaria baicalensis induces apoptosis in B-1F cells and that it or its constituents might be a good resource for searching new drugs, especially anti-cancer drugs. Moreover, Saiboku-to promoted B-1F cell proliferation, but Scutellaria baicalensis inhibited it, showing complexity of action of traditional Chinese medicines.

A 67-year-old female diagnosed as Hashimoto's thyroiditis in company with acquired leucoderma was reported. She first noticed the enlarged thyroid at the age of 36, and thereafter leucoderma made its appearance 30 years later. Though a significant association between these two diseases has been found in the literature thus far and they are considered to be of autoimmune origin, their coexistence is not so common clinically. In spite of PUVA treatment, a benefit effect was not obtained completely.

A 21-year-old male of Swyer-James syndrome is presented with clinical, angiographic, bronchographic and scintigraphic studies. He had a past history of recurrent bronchial asthma. A chest roentgenogram revealed unilateral hyperlucency of the left lung without any changes in volume. The small size of the pulmonary artery and its branches of the left lower lobe was visible by pulmonary angiography. Bronchography showed the bronchiectatic changes which consisted of moderate bronchial dilatation in an irregular beaded pattern with clubbed or tapered ends accompanied by absence of alveolar filling. A perfusion lung scan using 99mTc-macroaggregated albumin (99mTc-MAA) illustrated a perfusion defect in the left lower lobe. It was thought that recurrent pulmonary infections and asthmatic attacks were responsible for a pathological condition of this disease.

The characteristics of the changes of "senile lung" and normal values of the width of the paraspinal shadows on the chest roentgenographs were studied among 235 subjects aged from 70 to 97 without frank chest diseases. The ratio of upper transverse diameter (at the level of posterior 6th rib) to lower transverse diameter (at the top of right hemidiaphragm) on the frontal radiographs was significantly higher over the age of 85 than under 84, only in the female subjects. However, a lack of differences could be found in males. Therefore, "senile lung" was considered to be characteristic of the aging process, only for women. The width of the paraspinal shadow over the age of 70 was estimated to be normal in up to 19.9mm, and the index divided by the distance of descending aorta was up to 0.61, obtained from the value of 99% confidence limits.

High pressures and high magnetic field effects on magnetic and electrical properties of polycrystalline Mn_{2}Sb_{0.92}Ge_{0.08}, Mn_{2}Sb_{0.92}Sn_{0.08} and Mn_{2}Sb_{0.85}Sn_{0.15} were investigated. These compounds showed a first-order magnetic transition between the ferrimagnetic (FRI) and antiferromagnetic (AFM) phases for 150–250 K temperature range in a zero magnetic field. The pressure dependence of the AFM/FRI transition temperature was estimated to be −5.1×10^−2 GPa^−1 for Mn_{2}Sb_{0.92}Ge_{0.08}. The electrical resistivity changed abruptly by 50% for Mn_{2}Sb_{0.92}Sn_{0.08} and by 71% for Mn2Sb0.85Sn0.15 at the transition temperature. We confirmed the negative magnetoresistance over 60% for the Sn-substituted compounds.