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We fabricated terahertz (THz) wave emitters from high-temperature superconductor Bi2Sr2CaCu2O8+δ (Bi2212) single crystals annealed under oxygen gas (O2) flow and nitrogen gas (N2) flow conditions. To better understand the annealing effects of the crystal for the device, we evaluated both device properties and a c-axis lattice constant using x-ray diffraction. Compared to the N2-annealed sample, the O2-annealed sample shows higher critical current in the current–voltage characteristics and no clear emission. In addition, multiple hysteresis loops were observed above 75 K. Based on the x-ray diffraction measurements, it is suggested that the presence of multiple hysteresis loops observed in the I–V characteristics of the O2-annealed sample is caused by the existence of layers that have varying levels of oxygen content along the c-axis direction of the crystal. The formation of these layers is attributed to the deposition process of metallic thin films during the device fabrication procedure. This result indicates that the Bi2212 crystal surface of the O2-annealed sample is more sensitive than that of the N2-annealed one. The information is useful for preparing the Bi2212 crystals for THz-wave emitting devices.

The current status and the progress of research and development (R&D) activities for a Fusion DEMO reactor in the National Institutes for Quantum and Radiological Science and Technology (QST) Rokka...

We have investigated the pinning potential of high-quality single crystals of superconducting material CaKFe

We have investigated the pinning potential of high-quality single crystals of superconducting material CaKFe4As4 having high critical current density and very high upper critical field using both magnetization relaxation measurements and frequency-dependent AC susceptibility. Preliminary studies of the superconducting transition and of the isothermal magnetization loops confirmed the high quality of the samples, while temperature dependence of the AC susceptibility in high magnetic fields show absolutely no dependence on the cooling conditions, hence, no magnetic history. From magnetization relaxation measurements were extracted the values of the normalized pinning potential U*, which reveals a clear crossover between elastic creep and plastic creep. The extremely high values of U*, up to 1200 K around the temperature of 20 K lead to a nearly zero value of the probability of thermally-activated flux jumps at temperatures of interest for high-field applications. The values of the creep exponents in the two creep regimes resulted from the analysis of the magnetization relaxation data are in complete agreement with theoretical models. Pinning potentials were also estimated, near the critical temperature, from AC susceptibility measurements, their values being close to those resulted (at the same temperature and DC field) from the magnetization relaxation data.

We fabricated superconducting coils using 10-20 m-class round wires of 122-type iron-based superconductors (IBSs). Round wires and coils are fabricated by powder-in-tube method and hot-isostatic-press technique. Transport critical current (I c) of the whole (Ba,K)Fe2As2 coil is 46 A under the self-field at 4.2 K, and magnetic field at the center of the coil reaches 0.3 T. Although the edge of the long wire in the coil is damaged, the rest of the part is relatively homogeneous. Furthermore, the largest transport critical current density (J c) and I c in (Ba,K)Fe2As2 wires picked up from the coil reach 49 kAcm−2 and 44 A at 4.2 K under a magnetic field of 10 T, respectively. This value exceeds the previous highest transport J c of (Ba,K)Fe2As2 round wires. We also fabricated a (Ba,Na)Fe2As2 coil using long round wire with large superconducting core by react and wind method. Transport I c of the coil is significantly low due to cracks perpendicular to electric current flow direction, although magnetic J c in the round wire picked up from the coil reaches 40 kAcm−2 at 4.2 K under 4 T.

By the high pressure and high temperature solution method mixing CdSe fluxes, layered PbFCl-type HfP2-x Se x (x = 0.45) and HfSiSe single crystals were successfully grown and obtained under a high-pressure for the first time. It was clarified that the melting temperature of the solid solution was lowered by adding a small amount of CdSe. Typical sizes of ~ 180 × ~ 180 × ~ 20 μm 3 for HfP2-x Se x (x = 0.45) and ~ 120 × ~ 100 × ~ 20 μm 3 for HfSiSe were obtained and characterized by scanning electron microscopy (SEM) and energy-dispersive electron spectroscopy. X-ray diffraction analysis showed that HfP2-x Se x (x = 0.45) and HfSiSe were grown oriented c - axis. Magnetic susceptibility versus temperature measurement were performed for HfP2-x Se x (x = 0.45). Onset of the Tc was showed at around ~ 5.36 K for HfP2-x Se x (x = 0.45) single crystal. Here, the crystal growth and magnetic properties for HfP2-x Se x (x = 0.45) single crystal were presented.

Hybridization of Bogoliubov quasiparticles (BQPs) between the CuO_{2} layers in the triple-layer cuprate high-temperature superconductor Bi_{2}Sr_{2}Cu_{2}Cu_{3}O_{10+δ} is studied by angle-resolved photoemission spectroscopy (ARPES). In the superconducting state, an anticrossing gap opens between the outer- and inner-BQP bands, which we attribute primarily to interlayer single-particle hopping with possible contributions from interlayer Cooper pairing. We find that the d-wave superconducting gap of both BQP bands smoothly develops with momentum without an abrupt jump in contrast to a previous ARPES study. Hybridization between the BQPs also gradually increases in going from the off nodal to the antinodal region, which is explained by the momentum dependence of the interlayer single-particle hopping. As possible mechanisms for the enhancement of the superconducting transition temperature, the hybridization between the BQPs as well as the combination of phonon modes of the triple CuO_{2} layers and spin fluctuations represented by a four-well model are discussed.

Systematic monitoring of nearshore area provides useful information on sandy beaches over a wide range of temporal and spatial scales. In this study, accordingly, a simple local remote sensing system is developed to monitor the morphological variations of sandy beaches. This monitoring system consists of acquisition of geo-referenced video image of nearshore area from a small UAV (Unmanned Aerial Vehicle) and subsequent image analysis. Owing to the rapid development of information technology, high resolution photographic images of sea surface can be easily recorded at favorable location in a cost-efficient way. The subsequent quantification of morphological changes is carried out based on bright intensity patterns. First, the video images are converted to successive snapshots and rectified. After removing the small oscillations through semi-automatic identification of Ground Control Points (GCPs), the time-stack images of bright intensity variations are constructed for a series of cross-shore sections located at specified alongshore intervals. For each cross-section, the crest lines of waves are tracked out by inspecting the location of steep gradient in bright intensity variations. The local tracking results provide the celerity of waves. Combined with the observed wave period, the local water depth is estimated based on the linear dispersion relation. The system has been applied to the field observation of Uchinada Coast, Ishikawa, Japan facing to the Sea of Japan. The accuracy of geo-referencing was shown to be as small as a couple of pixels. The accuracy of morphological estimation based on image processing has been confirmed through comparison with a field survey using a jet bike. The image-based estimation results qualitatively reproduced the patterns of morphological variation. The typical error was in the range 0.2 to 0.8 m. These results demonstrated the capability of the developed system to remotely estimate the coastal morphology on sandy beaches.

Anisotropy of transport and magnetic properties of parent compounds of iron based superconductors is a key ingredient of superconductivity. In this work, we investigate in-plane and out-of-plane properties, namely thermal, electric, thermoelectric transport and magnetic susceptibility in a high quality BaFe

This paper reports a multi-throughput multi-organ-on-a-chip system formed on a pneumatic pressure-driven medium circulation platform with a microplate-sized format as a novel type of microphysiological system. The pneumatic pressure-driven platform enabled parallelized multi-organ experiments (i.e. simultaneous operation of multiple multi-organ culture units) and pipette-friendly liquid handling for various conventional cell culture experiments, including cell seeding, medium change, live/dead staining, cell growth analysis, gene expression analysis of collected cells, and liquid chromatography–mass spectrometry analysis of chemical compounds in the culture medium. An eight-throughput two-organ system and a four-throughput four-organ system were constructed on a common platform, with different microfluidic plates. The two-organ system, composed of liver and cancer models, was used to demonstrate the effect of an anticancer prodrug, capecitabine (CAP), whose metabolite 5-fluorouracil (5-FU) after metabolism by HepaRG hepatic cells inhibited the proliferation of HCT-116 cancer cells. The four-organ system, composed of intestine, liver, cancer, and connective tissue models, was used to demonstrate evaluation of the effects of 5-FU and two prodrugs of 5-FU (CAP and tegafur) on multiple organ models, including cancer and connective tissue.

We investigated difference in the transport properties between Al0.1In0.9Sb/InSb and Al0.1In0.9Sb/InAs0.1Sb0.9 quantum wells (QWs). The resistivity of InSb QWs increases exponentially with decreasing temperature, while that of InAs0.1Sb0.9 QWs is much lower than that of InSb QWs, showing low resistivity even at low temperature. Energy band diagram calculations of InAsxSb1−x/Al0.1In0.9Sb quantum wells (QWs) revealed that the bottom of the conduction band of the InAsxSb1−x well moves downward with increasing As content x. The bottom of the InSb QWs lies above the Fermi level (EF), resulting in depletion of the QW, while that in InAs0.1Sb0.9 QWs lies under EF at low temperature. These calculation results support the experimental difference of the resistivity and sheet carrier density between two types of the QWs well.

In order to clarify the taxonomic position of serotypes 20, 22 and 26 of Streptococcus suis , biochemical and molecular genetic studies were performed on isolates (SUT-7, SUT-286T, SUT-319, SUT-328 and SUT-380) reacted with specific antisera of serotypes 20, 22 or 26 from the saliva of healthy pigs as well as reference strains of serotypes 20, 22 and 26. Comparative recN gene sequencing showed high genetic relatedness among our isolates, but marked differences from the type strain S. suis NCTC 10234T, i.e. 74.8–75.7 % sequence similarity. The genomic relatedness between the isolates and other strains of species of the genus Streptococcus , including S. suis, was calculated using the average nucleotide identity values of whole genome sequences, which indicated that serotypes 20, 22 and 26 should be removed taxonomically from S. suis and treated as a novel genomic species. Comparative sequence analysis revealed 99.0–100 % sequence similarities for the 16S rRNA genes between the reference strains of serotypes 20, 22 and 26, and our isolates. Isolate STU-286T had relatively high 16S rRNA gene sequence similarity with S. suis NCTC 10234T (98.8 %). SUT-286T could be distinguished from S. suis and other closely related species of the genus Streptococcus using biochemical tests. Due to its phylogenetic and phenotypic similarities to S. suis we propose naming the novel species Streptococcus parasuis sp. nov., with SUT-286T ( = JCM 30273T = DSM 29126T) as the type strain.

The JT-60SA project has been implemented jointly by Europe and Japan since June 2007. After the disassembly of JT-60 from the torus hall had been completed in October 2012, the project achieved the major milestone of starting the tokamak’s assembly at the JAEA Naka site in January 2013 following the completion of the cryostat base in Europe and its transport to Japan. Procurement and assembly activities for components such as the superconducting magnet, cryogenic system, power supply, vacuum vessel, divertor and cryostat are progressing on track towards the start of operation in March 2019. In preparation for exploitation, the JT-60SA Research Plan was issued in December 2011, and the research integration activities are addressing JT-60SA data management, validation and analysis tools. This paper overviews the latest evolution of the project in terms of construction and exploitation for JT-60SA.

In ZrP1.25Se0.75, the superconducting transition temperature T c is increased from 5.8 K to 7.6 K when Sc atoms are partially substituted for Zr atoms having almost the same atomic radius as Sc atoms. Transport measurements show that holes are doped with substituting Sc atoms. The density of states in (Zr, Sc)P1.25Se0.75 is derived from band structure calculations and its implication in the doping behaviour and the increase of T c is discussed.

This work describes a metal-metal bonding process by the use of Cu nanoparticles as a filler material. The Cu particles used were prepared by reduction of Cu2+ with hydrazine in the presence of cetyltrimethylammonium bromide as a dispersing agent (uncoated Cu particles). Polypyrrole (PPy)-coated Cu nanoparticles were also used as the filler. Strong bonding for Cu discs was not obtained by using the PPy-coated particles. For the uncoated Cu particles, a shear strength required for separating the discs bonded by annealing at 400°C in H2 gas was as large as 18.1 MPa.

We measured electronic Raman spectra of nonstoichiometric Bi2+ x Sr2 −x CaCu2O8+ δ with x =0.1, 0.3 and stoichiometric Bi2Sr2Y0.08Ca0.92Cu2O8+ δ and investigated the effect of out-of-plane disorder on the superconducting B1 g Raman response. We observed that the B1 g peak energy is enhanced in Y-substituted Bi2212, compared with that in nonstoichiometric Bi2212. By contrast, for nonstoichiometric Bi2212, the B1 g peak energy remains constant, even if T c is significantly suppressed by disorder. This anomalous behavior is discussed in terms of the interplay between the pseudogap and superconducting gap.

All-trans retinoic acid and interferon-α increase CD38 expression on adult T-cell leukemia cells and sensitize them to T cells bearing anti-CD38 chimeric antigen receptors

JT-60 (JAERI Tokamak-60) started operating at the Naka Fusion Institute in 1985 as one of the world’s largest tokamaks with an outboard diverter configuration using hydrogen plasmas in Japan. Its modification to achieve higher plasma current with a single null open divertor was completed in 1991 (JT-60U, U = Upgrade), allowing it to use deuterium plasmas. Since then, JT-60U has addressed the physics issues of reactor plasmas, including ITER (International Thermonuclear Experimental Reactor) physics R&D (Research and Development), and has explored advanced tokamak regimes with high-βp and reversed shear modes for a commercially attractive fusion reactor—work which led to the conception of a Steady-State Tokamak Reactor (SSTR). A variety of additional heating and current drive systems to inject lower hybrid, ion cyclotron RF (Redio Frequency) waves, and positive-ion-based neutral beams have been equipped from the beginning to address the issues. A negative-ion-based neutral beam injector with 500-keV deuterons and electron cyclotron RF system were added to JT-60U in 1996 and 1999, respectively, and in-vessel modifications necessary to the accommodation of a W-shaped pumped divertor were completed in 1997. Ferritic steel tiles were installed inside the vacuum vessel to reduce the toroidal field ripple in 2005. The results produced in JT-60U made a significant impact on the design of ITER, and paved the promising way for the development of DEMO (DEMOnstration fusion reactor) toward early realization of fusion energy with not only world-record achievements in performance such as the highest fusion triple product and DT (Deuterium-Tritium fusion reaction)-equivalent fusion gain, but also important physics findings relevant to the advanced tokamak such as high bootstrap current fraction, internal transport barrier, and current hole with making the JT-60U equipment enhanced. Through the perspective of the reactor relevance, JT-60U has innovated the plasma confinement with finding the physics nature, enhanced the performance at a maximum, and sustained the performance integrated so as to resolve the issues in particular for steady-state operation. JT-60U operations ended in August 2008 to start the modifications for a fully superconducting tokamak, the JT-60SA (SA = Super Advanced), which is being constructed at the Naka site. Thus, JT-60U has paved the way for a prosperous future for the coming eras of fusion developments emphasized on long and stable sustainment of high performance plasmas in JT-60SA, ITER, and DEMO.

The JT-60SA experiment is one of the three projects to be undertaken in Japan as part of the Broader Approach Agreement, conducted jointly by Europe and Japan, and complementing the construction of ITER in Europe. It is a fully superconducting tokamak capable of confining break-even equivalent deuterium plasmas with equilibria covering high plasma shaping with a low aspect ratio at a maximum plasma current of Ip = 5.5 MA. In late 2007 the BA Parties, prompted by cost concerns, asked the JT-60SA Team to carry out a re-baselining effort with the purpose to fit in the original budget while aiming to retain the machine mission, performance, and experimental flexibility. Subsequently the Integrated Project Team has undertaken a machine re-optimization followed by engineering design activities aimed to reduce costs while maintaining the machine radius and plasma current. This effort led the Parties to the approval of the new design in late 2008 and hence final design and procurement activities have commenced. The paper will describe the process leading to the re-baselining, the resulting final design and technical solutions and the present status of procurement activities.

In the framework of the JT-60SA project, aiming at upgrading the present JT-60U tokamak toward a fully superconducting configuration, the detailed design phase led to adopt for the three main magnet systems a brand new design. Europe (EU) is expected to provide to Japan (JA) the totality of the toroidal field (TF) magnet system, while JA will provide both Equilibrium field (EF) and Central Solenoid (CS) systems. All magnet designs were optimized trough the past years and entered in parallel into extensive experimentally-based phases of concept validation, which came to maturation in the years 2009 and 2010. For this, all magnet systems were investigated by mean of dedicated samples, e.g. conductor and joint samples designed, manufactured and tested at full scale in ad hoc facilities either in EU or in JA. The present paper, after an overall description of magnet systems layouts, presents in a general approach the different experimental campaigns dedicated to qualification design and manufacture processes of either coils, conductors and electrical joints. The main results with the associated analyses are shown and the main conclusions presented, especially regarding their contribution to consolidate the triggering of magnet mass production. The status of respective manufacturing stages in EU and in JA are also evoked.

The mission of the JT-60SA project is to contribute to the early realization of fusion energy by supporting the exploitation of ITER and research towards DEMO by addressing key physics issues associated with these machines. The JT-60SA will be capable of confining break-even equivalent class high-temperature deuterium plasmas at a plasma current Ip of 5.5 MA and a major radius of ∼3 m lasting for a duration longer than the timescales characteristic of plasma processes, pursue full non-inductive steady-state operation with high plasma beta close to and exceeding no-wall ideal stability limits, and establish ITER-relevant high density plasma regimes well above the H-mode power threshold. Re-baselining of the project was completed in late 2008 which has been worked on since late 2007, where all the scientific missions are preserved with the newly designed machine to meet the cost objectives. The JT-60SA project made a large step forward towards its construction, which now foresees the first plasma in 2016. Construction of JT-60SA begins at Naka in Japan with launching the procurement of PF magnet, vacuum vessel and in-vessel components by Japan. In this year, the procurement of TF magnet, cryostat and power supply will be launched by Europe.

We investigate the recombination dynamics of positively charged and neutral biexcitons and excitons in a single InAs/GaAs quantum dot (QD) within a two-dimensional (2D) photonic bandgap (PBG). The 2D PBG makes the exciton lifetime four times longer and enhances photon-extraction efficiency compared to those without the PBG. Photon cross-correlation measurements demonstrate the cascade emissions of both charged and neutral biexcitons–excitons from the same QD. In the charged case, a hole in the p-shell relaxes into the s-shell between the cascade, and the corresponding transition is confirmed based on the spin configuration. The long exciton lifetime with the PBG helps us to reveal the spin dynamics that did not clearly appear in intrinsic QDs.

We investigated the spin–orbit interaction (SOI) in Al 0.1 In 0.9 Sb/Sn-doped InAs 0.1 Sb 0.9 quantum wells (QWs) with different doping levels using the weak anti-localization effect in the magneto-resistance. The inelastic scattering time is close to the T −1 law predicted theoretically for electron–electron interaction, and the spin–orbit scattering time is temperature independent as expected for the D'yakonov–Perel mechanism. The carrier-density dependence of zero-field spin-splitting energy extracted from the fits of magneto-resistance was examined by the theoretical calculation. The result confirms that the Dresselhaus SOI is much larger than the Rashba SOI in our QWs. The dominance of the Dresselhaus term in SOI originates in the large weight factor of InSb-based alloy.

We have investigated the structures, magnetic properties and spin polarization of bulk Fe2CrSi and Fe2Cr1-xVxSi Heusler alloys. Single-phase structures were obtained for all samples by setting the composition 22% forY-atom of X2YZ Heusler alloy. The saturation magnetization of Fe2Cr1-xVxSi for x 0.5 decreased monotonically with increasing V content, while their Curie temperatures Tc and spin polarization P remained constant. For alloys with x > 0.5, saturation magnetization decreased rapidly with increasing V content. Experimental results of spin polarization P were discussed from the viewpoint of the Fe, Cr and V partial density of states determined by the band calculation.

We examined the role of localized electrons in the accumulation layer of Sn-doped InSb quantum wells (QWs) with various wellwidths ( L w = 15 ∼ 150 nm ) . At liquid He temperatures, the samples with the sheet resistance ρ > ρ c = h / e 2 for L w 30 nm exhibit the variable-range hopping (VRH), while those with ρ ρ c f o r L w > 50 nm exhibit weak localization (WL), where ρ c is the quantum resistance. In particular, a part of the electrons (with density of N str = 8 × 1 0 10 cm − 2 ) from Sn donors are trapped at the interface states at low temperatures below 77 K. In the WL regime, we observed the small positive magnetoresistance (MR) peak arising from the weak anti-localization (WAL) in the presence of spin-orbit interaction (SOI). In contrast to the WAL in WL regime, the low-field MR in the VRH regime remains entirely negative surviving the SOI, indicating that the hopping MR due to the quantum interference (QI) is completely negative regardless of the SOI. This result supports the predictions based on the directed-path approach for forward-scattering paths ignoring the back-scattering return loops for the QI in the VRH.

Transport properties were investigated for undoped Al 0.1 In 0.9 Sb/ InAs 0.1 Sb 0.9 quantum wells (QWs), and two-carrier analyses were applied to the magnetic-field variations of the Hall coefficient and magnetoresistance at 77 K. The Hall coefficient increases with magnetic field, which shows coexistence of electrons and holes. This behaviour is similar to AlGaAsSb/ InAs QWs, which have a type-II band structure. Additionally, the Hall coefficient turns to decrease in more than 1 T, and the behaviour was not observed in the deep InAs QWs. This indicated that there are other electrons with different mobility. These are thought to be electrons extended over the QW, accumulated near the hetero-interface, and thermally excited in the barrier layer.