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We present the preliminary results of more than 160 h of time-series photometry on the subdwarf B pulsating star PG 1325+101 (Teff = 34 500 K log g = 6.1), obtained in March-April 2003 at nine different sites. The amplitude spectrum confirms the presence of the four frequencies found in the discovery run at the NOT in July 2001 (but with significantly lower amplitudes in two of them) and also shows at least two new low amplitude signals. Moreover, there is no sign of frequency splitting near the main peak at 7256 μHz, suggesting that this mode might be actually radial as indicated by the time-resolved spectroscopy (Østensen and Telting, 2004). [ABSTRACT FROM AUTHOR]

The gate bias dependent evolution of the Coulomb oscillations in a silicon-on-insulator nano-wire transistor is reported. Transport data obtained for a wide range of front- and back-gate bias strongly suggest that multiple quantum dots (QDs) with different potential depths are formed in the nano-wire channel. Our data can be clearly interpreted as arising from the turning on or off of one of these QDs as the back-gate bias is varied. Quantitative calculation based on the model of single-electron tunneling through two parallel QDs is in reasonable agreement with the measured data in the back-gate bias range where the third dot is not activated. [Copyright &y& Elsevier]

To reduce strain and the quantum‐confined Stark effect (QCSE), periodic trenches in an InGaN/GaN multi‐quantum well (MQW) are patterned by electron‐beam (e‐beam) lithography and the inductively‐coupled plasma (ICP) dry etching process. The effects of the fabricated structure are investigated by measuring cathodo‐luminescence (CL) spectra and comparing it with the data of an as‐grown sample without trench patterns. The peak wavelength of the prepared samples is clearly blue‐shifted, and it is confirmed that the strain and the QCSE are reduced by the effects of the trench structures. It is also confirm that the peak intensity of CL spectra shows a maximum when 90% of the active region is remaining, because the trench patterns reduce the light emitting area as well as the strain and the QCSE. [ABSTRACT FROM AUTHOR]

Abstract: We examined the structural properties and the electronic and magnetic structures of an Fe3O4 ultrathin film prepared by oxidizing a low-temperature-grown (T =95K) Fe film on GaAs(100), using the X-ray diffraction, X-ray absorption spectroscopy, and X-ray magnetic circular dichroism measurements. They show no clear contrast to those of an Fe3O4 film that was prepared by oxidizing room-temperature-grown Fe film. The interdiffusions of Ga and As atoms in the Fe3O4 films were further investigated using the resonant Fe3O4(400) diffractions at the Ga K- and As K-edge energies. It is shown that the Fe3O4 film that originated from the room-temperature-grown Fe film contains both Ga and As atoms, while the film that originated from the kinetically-stabilized Fe film contains only Ga atoms. This suggests that the kinetic stabilization in pristine Fe layers can block As interdiffusion effectively even after oxidization. [Copyright &y& Elsevier]

Element specific magnetic hysteresis loops of the interlayer exchange coupled CoFeB/Ru/[Co/Ni]4 structure were measured utilizing x-ray magnetic circular dichroism. It was found that the Co/Ni multilayer and the CoFeB layer have Ru thickness dependent oscillatory interlayer coupling. Due to its interlayer coupling with the perpendicularly magnetized Co/Ni multilayer, the CoFeB magnetization direction is slightly tilted out-of-plane from its in-plane magnetic easy axis. Quantitative measurements show that the tilting angle is small (<12°) and that a small in-plane magnetic field (∼50 Oe) applied to this structure will result in a completely in-plane CoFeB magnetization. [ABSTRACT FROM AUTHOR]

We grew single phase DyFeO3 (110) epitaxial films on SrTiO3(001) substrates in the layer-by-layer mode using the pulsed laser deposition. The Fe L2,3-edge x-ray magnetic linear dichroism and magnetic hysteresis confirm that the film shows the spin-canted antiferromagnetism at room temperature and undergoes the spin reorientation transition (SRT) upon cooling as the bulk. The SRT temperature is significantly reduced in the thin films due to the compressive strain and becomes below 5 K for the thickness <= 50 Å. [ABSTRACT FROM AUTHOR]

Random telegraph noise (RTN) having two discrete current levels was characterised in reverse current of GaN based light-emitting diodes. Through compared magnitude of the hysteresis with RTN amplitude in reverse current, it is confirmed that RTN causes the current-voltage (I-V) hysteresis. The mechanism of RTN was analysed by using a tunnelling equation. In addition, activation energy of the trap leading to RTN was characterised by analysis of the time constants with voltage and temperature. [ABSTRACT FROM AUTHOR]

Abstract: The electronic structure of amorphous semiconductor InGaO3(ZnO)0.5 thin films, which were deposited by radio-frequency magnetron sputtering process, was investigated using X-ray photoelectron spectroscopy and O K-edge X-ray absorption spectroscopy. The overall features of the valence and conduction bands were analyzed by comparing with the spectra of Ga2O3, In2O3, and ZnO films. The valence and conduction band edges are mainly composed of O 2p and In 5sp states, respectively. The bandgap of the films determined by spectroscopic ellipsometry was approximately 3.2 eV. Further, it is found that the introduction of oxygen gas during the sputter-deposition does not induce significant variations in the chemical states and band structure. [Copyright &y& Elsevier]

Electronic structures of Ni-doped CuFe1-x Nix O2 delafossite oxides (x = 0, 0.015, and 0.03) have been investigated by employing soft x-ray absorption spectroscopy and soft x-ray magnetic circular dichroism (XMCD). It is found that the valence states of Cu, Fe, and Ni ions are nearly monovalent (Cu+), trivalent (Fe3+), and divalent (Ni2+), respectively, and that they do not change with x. In contrast, the Cu 2p XMCD signals, which arise from the Cu2+ states, increase with increasing x. This study suggests that the increasing XMCD signals are presumably related to the formation of ferrimagnetic spinel impurities in CuFe1-x Nix O2. [ABSTRACT FROM AUTHOR]

Electronic structures of perovskite oxides of SrMn1-x Mox O3 (0 ≤x≤ 0.75) have been investigated by employing soft x-ray absorption spectroscopy (XAS) and photoemission spectroscopy (PES). It is found that the valence states of Mn ions change systematically from Mn4+ for x = 0, to nearly Mn3+ for x = 0.3, and Mn2+ for x = 0.5, and then remain as Mn2+ for x≥0.5. Both the Mo 3d core-level PES and Mo 3p XAS spectra show that the valence states of Mo ions remain unchanged as being hexavalent (Mo6+) for x≤0.5 but that they decrease for x>0.5 with increasing x. This study shows that Mo ions are mixed-valent for x>0.5 in SrMn1-x Mox O3, either with the Mo4+-Mo6+ configuration or with the Mo4+-Mo5+-Mo6+ configuration. [ABSTRACT FROM AUTHOR]

Two strategies are introduced herein to improve current drivability of tunnel field‐effect transistors (TFETs). First, gate‐to‐channel coupling is increased by ∼22% in terms of effective gate capacitance (Cox) with the help of hemi‐cylindrical device architecture. A novel iterative corner rounding process was developed for highly reliable gate dielectric formation without field crowding at sharp corner. The second approach is change channel orientation. The 〈100〉 and 〈110〉 oriented‐channel TFETs were fabricated on (100) silicon surface. Consequently, both planar and hemi‐cylindrical structures show consistent results that 〈110〉 is far better than 〈100〉 for higher on‐current (Ion). With these two structural improvements, the 〈110〉 hemi‐cylindrical TFET shows ∼30× higher Ion than that of the control (i.e. 〈100〉 planar TFET). [ABSTRACT FROM AUTHOR]

Three novel HLA alleles, HLA-A*26:118, DQB1*02:65 and DPB1*05:01:07, were identified and confirmed by monoallelic sequencing., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The HLA-C*14:02:01:03 differs by a single nucleotide at intron 5 (2157 C>T) compared with C*14:02:01:01., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The new allele, DRB1*04:10:03, showed one nucleotide difference with DRB1*04:10:01 (705C>T)., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The new allele A*02:465 showed one nucleotide difference with A*02:06:01 (172G>A)., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

To obtain real-time dose information in photon-beam therapy using a clinical linear accelerator, we fabricated a novel Cerenkov fiber-optic dosimeter using two plastic optical fibers without employing a scintillator. In this study, the light intensity and spectrum of Cerenkov radiation induced by a high-energy photon beam were measured as functions of the irradiation angle and the length difference between the two plastic optical fibers in the dosimeter probe. Also, we obtained a percentage depth dose curve for a 6 MV photon beam with a field size of 10 × 10 cm(2) according to the depth of the solid water phantom. Based on the results of this study, it is anticipated that the proposed Cerenkov fiber-optic dosimeter can be developed as a useful dosimeter to accurately obtain dose information prior to conducting radiotherapy.

We employ antiferromagnetic tunneling anisotropic magnetoresistance to study the behavior of antiferromagnetically ordered moments in IrMn exchange coupled to NiFe. Experiments performed by common laboratory tools for magnetization and electrical transport measurements allow us to directly link the broadening of the NiFe hysteresis loop and its shift (exchange bias) to the rotation and pinning of antiferromagnetic moments in IrMn. At higher temperatures, the broadened loops show zero shift, which correlates with the observation of fully rotating antiferromagnetic moments inside the IrMn film. The onset of exchange bias at lower temperatures is linked to a partial rotation between distinct metastable states and pinning of the IrMn antiferromagnetic moments in these states. The observation complements common pictures of exchange bias and reveals an electrically measurable memory effect in an antiferromagnet.

A spin valve is a microelectronic device in which high- and low-resistance states are realized by using both the charge and spin of carriers. Spin-valve structures used in modern hard-drive read heads and magnetic random access memoriescomprise two ferromagnetic electrodes whose relative magnetization orientations can be switched between parallel and antiparallel configurations, yielding the desired giant or tunnelling magnetoresistance effect. Here we demonstrate more than 100% spin-valve-like signal in a NiFe/IrMn/MgO/Pt stack with an antiferromagnet on one side and a non-magnetic metal on the other side of the tunnel barrier. Ferromagneticmoments in NiFe are reversed by external fields of approximately 50  mT or less, and the exchange-spring effect of NiFe on IrMn induces rotation of antiferromagnetic moments in IrMn, which is detected by the measured tunnelling anisotropic magnetoresistance. Our work demonstrates a spintronic element whose transport characteristics are governed by an antiferromagnet. It demonstrates that sensitivity to low magnetic fields can be combined with large, spin-orbit-coupling-induced magnetotransport anisotropy using a single magnetic electrode. The antiferromagnetic tunnelling anisotropic magnetoresistance provides a means to study magnetic characteristics of antiferromagnetic films by an electronic-transport measurement.

We investigated the orbital anisotropy of LuFe(2)O(4) using the Fe L(2,3)- and O K-edge x-ray absorption spectroscopy (XAS) and cluster model calculations. X-ray magnetic circular dichroism reveals a surprisingly large orbital magnetic moment (m(o) approximately 0.8 micro(B)/f.u.), which originates the giant magnetic anisotropy. The polarization dependent XAS enables us to identify the orbital states and occupations, different from the band calculation predictions. These findings were examined by using the cluster model analysis, which also explains the orbital magnetic moment as well as the total moment (2.9 micro(B)/f.u.). Taking into account the charge order, we also determined the spin structure.

We investigated the electronic structure of 5d transition-metal oxide Sr2IrO4 using angle-resolved photoemission, optical conductivity, x-ray absorption measurements, and first-principles band calculations. The system was found to be well described by novel effective total angular momentum Jeff states, in which the relativistic spin-orbit coupling is fully taken into account under a large crystal field. Despite delocalized Ir 5d states, the Jeff states form such narrow bands that even a small correlation energy leads to the Jeff=1/2 Mott ground state with unique electronic and magnetic behaviors, suggesting a new class of Jeff quantum spin driven correlated-electron phenomena.

Searches for extrasolar planets have uncovered an astonishing diversity of planetary systems, yet the frequency of solar system analogs remains unknown. The gravitational microlensing planet search method is potentially sensitive to multiple-planet systems containing analogs of all the solar system planets except Mercury. We report the detection of a multiple-planet system with microlensing. We identify two planets with masses of approximately 0.71 and approximately 0.27 times the mass of Jupiter and orbital separations of approximately 2.3 and approximately 4.6 astronomical units orbiting a primary star of mass approximately 0.50 solar mass at a distance of approximately 1.5 kiloparsecs. This system resembles a scaled version of our solar system in that the mass ratio, separation ratio, and equilibrium temperatures of the planets are similar to those of Jupiter and Saturn. These planets could not have been detected with other techniques; their discovery from only six confirmed microlensing planet detections suggests that solar system analogs may be common.

We investigated electronic structure of hexagonal multiferroic YMnO3 using the polarization dependent x-ray absorption spectroscopy (XAS) at O K and Mn L(2,3) edges. The spectra exhibit strong polarization dependence at both edges, reflecting anisotropic Mn 3d orbital occupation. Moreover, the O K edge spectra show that Y 4d states are strongly hybridized with O 2p ones, resulting in large anomalies in Born effective charges on off-centering Y and O ions. These results manifest that the Y d(0)-ness with rehybridization is the driving force for the ferroelectricity, and suggest a new approach to understand the multiferroicity in the hexagonal manganites.

We investigated ferromagnetism of a newly discovered ferromagnetic semiconductor Co-doped anatase TiO2 thin film, using the magnetic circular dichroism (MCD) at the Co L(2,3) absorption edges. The magnetic moment was observed to be approximately 0.1 micro(B)/Co in the measurements, but the MCD spectral line shape is nearly identical to that of Co metal, showing that the ferromagnetism is induced by a small amount of clustered Co. With thermal treatments at approximately 400 degrees C, the MCD signal increases, and the moment reaches up to approximately 1.55 micro(B)/Co, which is approximately 90% of the moment in Co metal. In the latter case, the cluster size was observed to be 20-60 nm.

We experienced a rare case of thoracic outlet syndrome caused by hypertrophic nonunion of the first rib. A diagnosis was made mainly upon provocative tests and imaging studies. Pain and tingling could be reproduced and the radial pulse obliterated by the hyperabduction test. Abundant callus formation on the posterior aspect of the first rib with fracture line was visible on plain radiograph. Two-dimensional computed tomography showed right thoracic outlet narrowing mainly caused by the mass-effect of the callus. Dynamic arteriographic studies revealed an external compression of the right subclavian artery and duplex ultrasonography demonstrated a reduction in right subclavian artery blood flow when the shoulder is in 90 degrees of abduction. Surgery was performed after the conservative management for three months which failed to relieve the patient of his complaints. Resection of the first rib via transaxillary approach was undergone uneventfully in combination with the myotomy of the scalenus anticus muscle. At postoperative one year follow up, the patient was free of symptoms, and had a full range of motion of the right shoulder with no evidence of arterial insufficiency.

In the Far East, hepatic resection is the definitive treatment for complicated intrahepatic stones (IHS). However, many investigators have reported that the associated intrahepatic biliary stricture is the main cause of treatment failure. A retrospective comparative study was undertaken to clarify the long-term efficacy of hepatic resection for treatment of IHS and to investigate the clinical significance of intrahepatic biliary stricture in treatment failure after hepatic resection performed in 44 patients with symptomatic IHS. The patients were divided into two study groups: group A, with intrahepatic biliary stricture (n = 28) and group B, without stricture (n = 16). Residual or recurrent stones, recurrence of intrahepatic biliary stricture, late cholangitis, and final outcomes were analyzed and compared statistically between the two groups. The patients were followed up for a median duration of 65 months after hepatectomy. The overall incidence of residual or recurrent stones was 36% and 11%, respectively, in groups A and B. The initial treatment failure rate was 50% in group A and 31% in group B. Intrahepatic biliary stricture recurred in 46% of patients in group A, while none of the group B patients had biliary stricture recurrence (P = 0.001). More than two-thirds of the restrictures in group A were identified at the primary site. The incidence of late cholangitis was higher in group A (54%) than in group B (6%) (P = 0. 002). Three-quarters of the patients with cholangitis in group A had severe cholangitis, that was recurrent, and related to stones and strictures (n = 11). They and 2 asymptomatic patients in group B required secondary procedures done at a median of 12 months after hepatectomy. Final outcomes after hepatectomy with or without secondary management were good in 80%, fair in 16%, and poor in 4% of our 44 patients. Most recurrent cholangitis after hepatectomy in patients with IHS was related to recurrent intrahepatic ductal strictures. Therefore, to be effective, hepatic resection should include the strictured duct. However, with hepatectomy alone it is difficult to clear the IHS or relieve the ductal strictures completely, particularly in patients with bilateral IHS, so perioperative team approaches that include both radiologic and cholangioscopic interventions should be combined for the effective management of IHS.

To elucidate the Ca2+ release mechanisms in the rabbit coronary artery, arterial preparations were permeabilized with beta-escin and changes in tension were measured under varying experimental conditions. Additionally, we investigated properties and distribution of two kinds of Ca2+ release mechanisms, Ca2+-induced Ca2+ release (CICR) and IP3-induced Ca2+ release (IICR). The results obtained were summarized as follows; 1. When a rabbit coronary artery was incubated in a relaxing solution containing 30 microM beta-escin for 40 min. sensitivity to externally added Ca2+ was much higher in beta-escin permeabilized muscle than in intact preparations. The contractile effect of IP3 in beta-escin permeabilized muscle was also demonstrated; 2. Caffeine and IP3 contracted coronary arteries were permeabilized with beta-escin, but the amplitude of contraction was much larger in the presence of caffeine than of IP3. 3. Intracellular heparin completely inhibited the contractions induced by IP3, but not those by caffeine. On the other hand, procaine inhibited the responses to caffeine, but not those to IP3. Ryanodine inhibited both the caffeine- and IP3-induced contractions. 4. The amplitude of contractile responses was much larger to the maximal stimulation of CICR by applying caffeine than to the maximal stimulation of IICR by applying IP3. After the maximal CICR stimulation by caffeine, the activation of IICR by IP3 without the reloading of Ca2+ could no longer evoke contraction. On the other hand, after the maximal IICR activation, the activation of CICR could still evoke contraction although the amplitude of the contraction was smaller when compared with the case without the initial IICR stimulation. 5. Acetylcholine contracted coronary artery smooth muscles were permeabilized with beta-escin. However, in the absence of added guanosine triphosphate (GTP), the responses were very small. Acetylcholine-induced contraction was inhibited by heparin, but not by procaine. From the above results, it may be concluded that there are two kinds of mechanisms of Ca2+ release, CICR and IICR, in the rabbit coronary artery smooth muscle cell. Also, whereas the CICR mechanism distributes on the membrane of the whole smooth muscle Ca2+ store, the IICR mechanism distributes only on a part of it.