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A new 320 GHz solid-state source interferometer is installed in the Heliotron J helical device to explore the physics of high-density plasmas (ne > 2–3 × 1019 m−3, typically) realized with advanced fueling techniques. This interferometry system is of the Michelson type and is based on the heterodyne principle, with two independent solid-state sources that can deliver an output power of up to 50 mW. A high time resolution measurement of

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A triple antiemetic therapy combining aprepitant (APR) with conventional double antiemetic therapy, including 5-hydroxytryptamine 3 receptor antagonist (5-HT₃-RA) and dexamethasone (DEX), is recommended for preventing chemotherapy-induced nausea and vomiting induced by a carboplatin (CBDCA) regimen. However, consensus on the additive effects of APR for gynecological patients on a combined regimen of paclitaxel and CBDCA (TC regimen) has yet to be reached. This retrospective study investigated the antiemetic effects of palonosetron and DEX (PD therapy) and granisetron and DEX with APR (GDA therapy) in patients with gynecologic cancer and who underwent their first TC regimen cycle between April 2017 and March 2020 at the Gunma University Hospital Outpatient Chemotherapy Center. The results showed that the complete response rate of the 92 patients who underwent PD therapy (PD group) and the 46 patients who underwent GDA therapy (GDA group) were both 80.4% (p = 1.000), and the complete control rates of the PD and GDA groups were 78.3% and 80.4%, respectively (p = 0.828), resulting in no significant difference. Furthermore, we observed no significant difference between the PD and GDA groups in the incidence of grade ≥2 nausea, vomiting, and anorexia (nausea: 7.6% vs. 0%, p = 0.095; vomiting: 4.3% vs. 0%, p = 0.301; and anorexia: 9.8% vs. 2.2%, p = 0.164). Concerning adverse events, compared to the PD group, the GDA group showed significantly higher incidence of grade ≥2 malaise (7.6% vs. 19.6%, p = 0.039). Given the lack of difference in the antiemetic effects of PD and GDA therapies, antiemetic therapy should be selected carefully for individual patients by accounting for the incidence of adverse reactions and interactions with APR.

TJ-II stellarator results on modelling and validation of plasma flow asymmetries due to on-surface potential variations, plasma fuelling physics, Alfvén eigenmodes (AEs) control and stability, the interplay between turbulence and neoclassical (NC) mechanisms and liquid metals are reported. Regarding the validation of the neoclassically predicted potential asymmetries, its impact on the radial electric field along the flux surface has been successfully validated against Doppler reflectometry measurements. Research on the physics and modelling of plasma core fuelling with pellets and tracer encapsulated solid pellet injection has shown that, although post-injection particle radial redistributions can be understood qualitatively from NC mechanisms, turbulence and fluctuations are strongly affected during the ablation process. Advanced analysis tools based on transfer entropy have shown that radial electric fields do not only affect the radial turbulence correlation length but are also capable of reducing the propagation of turbulence from the edge into the scrape-off layer. Direct experimental observation of long range correlated structures show that zonal flow structures are ubiquitous in the whole plasma cross-section in the TJ-II stellarator. Alfvénic activity control strategies using ECRH and ECCD as well as the relation between zonal structures and AEs are reported. Finally, the behaviour of liquid metals exposed to hot and cold plasmas in a capillary porous system container was investigated.

The Pa α line (1875.13 nm) in the near-infrared (NIR) region was evaluated to apply Stark broadening of the line spectrum to the electron density measurement of the small-pellet ablation cloud in Heliotron J, a medium-sized helical-axis heliotron device. Pa α is three-to-four times broader than the visible H β line (486.13 nm) for the same electron density. Using a portable NIR spectrometer, preliminary proof-of-concept experiments determined the marginal density, below which the broadening was undetectable. The lower detection density limit can be decreased using a narrower entrance slit or a denser grating.

Background Global longitudinal strain (GLS) is an echocardiographic marker to detect subclinical left ventricular systolic dysfunction prior to the appearance of reduced left ventricular ejection fraction (LVEF). Reduced GLS identified in patients with maintenance hemodialysis (HD) has been reported to be a predictor of their higher mortality and cardiovascular events. On the other hand, pharmacological stress 13N-ammonia positron emission tomography (13N-NH3-PET) has been an established and reliable imaging modality to evaluate myocardial perfusion expressed as coronary flow reserve (CFR) or maximal stress myocardial blood flow (MBF). CFR and MBF are powerful parameters to detect coronary artery disease and to predict cardiovascular events and mortality. However, association between GLS and those myocardial perfusion parameters are not fully understood. Purpose：The aim of this study was to evaluate the relationship between GLS and the myocardial perfusion parameters of 13N-NH3-PET in HD patients with preserved LVEF. Methods We studied 24 HD patients (mean age 67 years, 67% male) who underwent ATP stress 13N-NH3-PET as well as transthoracic echocardiography including 2-dimensional speckle tracking imaging for suspected ischemic heart disease. Exclusion criteria were as follows: LVEF Results Mean GLS in all patients was -16.2 ± 3.6%. The patients were divided into 2 groups based on GLS: patients with reduced GLS ( Conclusion Reduced GLS was significantly associated MPA. MPA may be one of the major contributors to the reduction in GLS in HD patients with preserved LVEF.

Polycyclic aromatic ketones emit very weak fluorescence, but their fluorescence is significantly enhanced by about one hundred times after preliminary irradiation of their degassed solution. To investigate the mechanism of such fluorescence enhancement, liquid chromatography/time-of-flight mass spectrometry measurements were performed for degassed methanol, ethanol, and acetonitrile solutions of 6 H -benzo[ cd ]pyren-6-one (naphthanthrone), in which fluorescence enhancement had been induced. As a result, two kinds of photochemical products were identified as the substance causing fluorescence enhancement: they were produced by dehydrogenation and dehydration of adducts of a solvent molecule to naphthanthrone. On the basis of the findings, the mechanism of the fluorescence enhancement of naphthanthrone was discussed. Fluorescence enhancement; 6H-benzo[cd]pyren-6-one; Polycyclic aromatic ketones; Liquid chromatography-mass spectrometry; Photochemical reaction

In this study, we developed a new frequency-tuning method for 700-MHz nuclear magnetic resonance (NMR) pickup coils. We determined an optimal Helmholtz-type one-turn coil, by using an electromagnetic simulator, and fabricated a pickup coil using YBa 2 Cu 3 O 7-δ (YBCO) thin films. We examined the resonance frequency shift of the pickup coils obtained with a sapphire plate by using a 3-D electromagnetic-field simulator and obtained a 31.5-MHz shift. We also examined the frequency shift obtained using a quasi-NMR pickup coil system and found that it was 29.3 MHz. This value is sufficient for the frequency tuning in an actual NMR system. It became clear that resonance frequency tuning using a sapphire plate was possible.

Recently, even a small cube satellite carries a Ku-band transponder and, then, its reception system is required in an earth radio station. A local oscillator (LO) frequency is so high that control and management of the frequency and phase becomes a big issue. We propose optoelectronic frequency conversion using an electro-absorption modulated laser, where LO-on-fiber and IF-on-fiber is transmitted as uplink and downlink, respectively, in a single fiber. The electro-absorption modulator functions as a photodiode to the uplink LO-on-fiber signal as well as the light modulator to convert radio frequency subcarrier in this system.

We propose a Helmholtz-type probe coil that uses a high-temperature superconductor (HTS) for use as 700-MHz nuclear magnetic resonance (NMR) RF coils with a high unloaded quality factor (Q u ). We analyzed the microwave resonant properties of a one-turn coil set face-to-face. The coils were made of a YBa 2 Cu 3 O 7-δ (YBCO) film deposited on an r-plane sapphire substrate. The film thickness was 300 nm. The resonant frequency was found to split into in-phase (lower frequency) and out-phase (higher frequency) modes. We focused on the self-resonant frequency of the one-turn coil. We simulated the horizontal magnetic field caused by the RF coil. Although the coil could generate a sufficiently large transverse magnetic field in the in-phase mode, such a large field could not be generated in the out-phase mode. Therefore, we decided to use the in-phase mode. We also measured and simulated Qu to confirm that it was large enough for use in the 700-MHz NMR system.

Dog treats might be contaminated withSalmonella. In Canada and the USA, outbreaks of human salmonellosis related to exposure to animal-derived dog treats were reported. Consequently, surveillance data onSalmonellacontamination of dog treats have been gathered in many countries, but not in Japan. In the current study, we investigated whether dog treats in Japan were contaminated withSalmonella. Overall, 303 dog treats (of which 255 were domestically produced) were randomly collected and the presence ofSalmonellainvestigated. Seven samples were positive forSalmonella entericasubsp.enterica. Among these isolates, three were identified as serovar 4,5,12:i:–; two were serovar Rissen; and two were serovar Thompson. All serovar 4,5,12:i:– and Thompson isolates were resistant to one or more drugs. Two serovar Rissen isolates were fully susceptible to all tested antimicrobial agents. AllSalmonellaisolates were susceptible to cefotaxime, ciprofloxacin and nalidixic acid. The geneblaTEMwas detected in two serovar 4,5,12:i:– isolates. TheblaCTX−MandblaCMYgenes were not detected in any isolates. This study demonstrated that dog treats in Japan could constitute a potential source of dog and humanSalmonellainfections, including multidrug-resistantSalmonellaisolates.

We have developed a bandwidth and a center frequency tuning method for use in high-temperature superconducting microstrip filters. A pair of waveguide is placed between the resonators, and the bandwidth is adjusted by changing the switch states of the waveguides. Additional electrical pads are placed open ends of the resonators for tuning the center frequency. Pads are also placed around the input/output coupled-line elements to enable the external quality factors to be adjusted, thereby reducing the insertion loss caused by tuning. A prototype three-pole tunable bandpass filter was fabricated by depositing YBa2Cu3O7 thin film on an MgO substrate and has a measured center frequency of 4.83 GHz and bandwidth of 121 MHz. Use of the waveguides to adjust the coupling coefficients, the electrical pads to adjust the effective lengths of the resonators and the pads to adjust the external quality factors resulted in 120-MHz bandwidth tuning and 400-MHz center frequency tuning without increased insertion loss.

A high-temperature superconducting stripline (SL) transmit filter with shuttle-shape resonators is described that improves power handling and out-of-band rejection. A cascaded quadruplet (CQ) design is used to produce a pair of attenuation poles for obtaining sharp cutoff characteristics. The shuttle-shape resonators improve power handling and out-of-band rejection. Placement of additional patch conductors in the upper layer of the resonator edges further improves power handling. An electromagnetic simulator based on the moment method was used to design a four-pole SL CQ filter with shuttle-shape resonators (5.0-GHz center frequency and 100-MHz bandwidth). Simulation using the electromagnetic simulator showed that the out-of-band rejection was improved and frequency response of the filter was nearly symmetric. The maximum current density of the shuttle-shape filter was approximately 19% lower than that of a four-pole SL CQ filter with straight-line resonators. That of the shuttle-shape filter with the additional patch conductors was approximately 24% lower.

We investigated power handling capability of a high-temperature superconducting transmit filter using a stripline (SL) structure. The filter is composed of three-pole half-wavelength straight-line resonators with a 5.0-GHz center frequency and a 100-MHz bandwidth. Simulation results showed that an SL filter is 47% the size of a conventional microstripline (MSL) filter due to the much shorter distance between resonators resulting from a weak coupling. However, the maximum surface current of the SL filter was approximately 1.4 times higher than that of an MSL filter. To reduce the maximum surface current, we increased the spacing between resonators. The modified SL filter was 62% the size of the MSL filter and almost the same maximum surface current. These results indicate that the spacing between resonators is an important factor in designing SL filters with high power handling capability and that an SL filter can be made smaller than an MSL filter with the same power handling capability.

We have developed a bandwidth and a center frequency tuning method for use in high-temperature superconducting microstrip filters. Several π-shaped waveguides are placed between the resonators, and the bandwidth is adjusted by changing the switch states of the waveguides. Additional electrical pads are placed open ends of the resonators for tuning the center frequency. Pads are also placed around the input/output coupled-line elements to enable the coupling strength between the coupled-line and resonator to be adjusted, thereby reducing the insertion loss caused by tuning. A prototype three-pole tunable bandpass filter was designed and analyzed using an electromagnetic simulator based on the moment method. The filter was designed at a center frequency of 5.00 GHz and a bandwidth of 150 MHz. The simulated bandwidth and center frequency of the filter were tuned from 150 to 300 MHz and 4.5–5 GHz without degradation of the insertion loss, respectively.

The inductive method/permanent-magnet method for measuring the critical current density jC in a high-temperature superconducting (HTS) tape have been simulated numerically. To this end, a numerical code has been developed for analyzing the time evolution of a shielding current density in an HTS sample. The results of computations show that, in the inductive method, the edge effects lead to the degradation of the jC-measurement accuracy. In contrast, it is found that, even if the magnet is placed near the edge, the maximum repulsive force is roughly proportional to jC. This means that the permanent-magnet method is applicable to measure jC near the edge.

We developed a non-destructive and contactless system for measuring the critical current (Ic) in YBa2Cu3O7-δ (YBCO)-coated conductors by using a permanent magnet (Sm2Co17). This Ic measurement method is based on the repulsive force (Fr) between the magnet and the shielding current in high-temperature superconductor-coated conductors. We measured Fr using a high-resolution load sensor and found that accurate Fr could be determined without the effect of thick copper film on the YBCO thin film and Hastelloy tape of the substrate. We can determine Ic from Fr0, which is the maximum repulsive force determined from an extrapolated value of the Fr vs. L curve for L = 0 mm, described in our previous paper. We show that the permanent magnet method can be used to determine the longitudinal Ic distribution and large-scale defects in YBCO-coated conductors. In addition, it turned out from this experiment that the permanent magnet method was effective to rapidly measure the longitudinal Ic distribution of long-scale coated conductors.

We developed trimming techniques for superconducting tunable filters with a dielectric tuning plate and dielectric trimming rods. We designed a 5-pole filter with 5-GHz center frequency and 100-MHz bandwidth using an electromagnetic field analysis simulator. We proposed the trimming techniques by using a trimming library. A trimming library refers to a collection of calculated data of frequency responses that is assembled in order to compare it with experimental data. We constructed the trimming library using a circuit analysis simulator (S-NAP). First, we designed a conventional π -type equivalent circuit with optimal band-pass filter (BPF) characteristics. We determined all C and L values to meet the specifications of the filter by using the S-NAP. Next, we calculated the filter characteristics by C values of each resonator. The changes in C were assumed to be 1%. The filter characteristics changed substantially with a 1% reduction in C. We were able to determine the most adjusting points for the trimming rods using the trimming library consisting of S11 properties. These results indicate that our method will be useful for the next generation of software-defined radio (SDR) systems.

We investigated the dc magnetic field and temperature dependences of the microwave intrinsic surface resistance (Rsint) of YBa2Cu3Oy (YBCO) superconducting thin films with various thicknesses. We used YBCO films from 100, 200, and 300 nm thick YBCO films deposited on CeO2/Al2O3 substrates. The Rsint is means the surface resistance of YBCO film without the dielectric loss of the substrates. The Rsint was obtained from measured surface resistance (Rs) by using a phenomenological equation. The Rs was measured using the dielectric resonator method at 21.8 GHz. A dc magnetic field of up to 5.0 T was applied parallel to the c-axis of the superconducting thin films during the Rs measurements. The Rsint of the YBCO thin films increased when the dc magnetic field was applied. These relations could be explained with the two-fluid model for high-frequency and high-magnetic field limits. The Rsint ratio (defined as Rsint (5T)/Rsint (0T)) slightly decreased with the film thickness. These results indicate that the Rsint of HTS films depends on the film thickness in the dc magnetic field and the Rsint in a dc magnetic field may be related to the pinning center in the HTS films.

Heat transport in reduced mass targets irradiated with a high-intensity laser pulse was studied. Kα lines from partially ionized chlorine embedded in the middle of a triple-layered plastic target were measured to evaluate bulk electron temperature in the tracer region inside the target. Two groups of Kα lines, one from Cl+–Cl6+ (hereby called “cold Kα”), and the other from Cl9+ and Cl10+ (“shifted Kα”) are observed from different regions within the target. Two-dimensional collisional particle-in-cell simulations show two distinct heating mechanisms occurring concurrently. These processes, which made the target temperature distribution non-uniform, are responsible for producing the two groups of Kα lines in the experiment. The blue shift of cold Kα lines in the experiment is the signature of higher temperatures achieved by the refluxing heating in smaller mass targets.

We have designed a high-temperature superconducting (HTS) transmit filter with step impedance resonators (SIRs). A transmit filter using half-wavelength straight-line resonators requires substantial spacing between adjacent resonators. This means that the filter needs a large substrate and that the number of poles is limited. Using SIRs overcomes this problem because SIRs are compact and have weak coupling. An electromagnetic simulator based on the moment method was used to design the SIR filter, which has a center frequency of 5 GHz and a bandwidth of 120 MHz. Simulation showed that it is approximately 19% smaller than a conventional half-wavelength straight-line resonator filter. Additionally, the maximum surface current is approximately 17% less than that of the conventional filter.

We have developed a method for tuning the bandwidth of a high-temperature superconducting (HTS) microstrip filter. Several π-shaped waveguides are placed between the resonators, and the bandwidth is tuned in discrete steps by changing the switch states of the waveguides, which changes the coupling coefficient between the resonators. The filter contains 3-pole half-wavelength straight-line resonators and two π-shaped waveguides for bandwidth tuning. It also has several electrical pads distributed around the feed lines for trimming after tuning. The filter was fabricated by depositing YBa2Cu3O7 thin film on an MgO substrate and has a measured center frequency of 5.17 GHz and bandwidth of 220 MHz. Use of the π-shaped waveguides to adjust the coupling coefficients and the electrical pads to adjust the external quality factors resulted in 80-MHz bandwidth tuning without increased insertion loss.

We designed a 5-GHz miniaturized 8-pole bandpass filter (BPF) using superconducting microstrip quasi-spiral resonators (QSRs) for international mobile telecommunication (IMT)-advanced receiving applications. We used the QSRs with line width and spacing equal to 10 μm for further miniaturization, and investigated a relationship between the structure of the QSR and the unloaded quality factor (Q u ). The Q u of the optimized QSR of approximately 25,000 was obtained. It was difficult to design a BPF using miniaturized QSRs with high Q u because of strong cross couplings between QSRs. The λ g /8-line inserted inverters were effective in decreasing the unwanted cross couplings. Using these QSR and the λ g /8-line inserted inverters, 8-pole cascaded quadruplet (CQ) BPF was designed. We found that it was possible to design a miniaturized BPF with high Q u .

The permanent magnet method measuring a critical current density in high temperature superconducting (HTS) thin films was experimentally and numerically investigated. The permanent magnet method was a contactless and nondestructive method for measuring a critical current density of HTS films. A permanent magnet was brought closer to an HTS thin film. A load sensor measured the electromagnetic force acting on an HTS thin film. As the results, it was found that the maximum repulsive force was approximately proportional to the critical current density. The electromagnetic behavior of the shielding current density in an HTS was formulated by the time-dependent integro-differential equations. The element-free Galerkin method and the completely implicit method were adopted for the system discretization. By using the numerical code, the permanent magnet method was reproduced numerically. Results of the computations showed that the critical current density was approximately proportional to the maximum repulsive force and that the evaluated location of the critical current density by the permanent magnet method was obtained by the numerical code. In addition, the permanent magnet method system was improved for measuring the spatial distribution of critical current densities of HTSs.

We have developed a technique for tuning high-temperature superconducting (HTS) microstrip filters in which additional electric pads are placed at the open ends of the resonators for tuning the center frequency. Pads are placed along one side of the open ends of the resonators to enable the effective lengths of the resonators to be adjusted, thereby shifting the center frequency. Pads are also placed around the I/O coupled-line elements to enable the coupling strength between the coupled-line and resonator to be adjusted, thereby reducing the insertion loss caused by tuning. The pads consist of line-and-space patterns. The former are electrically connected to the resonators, and the latter are electrically connected to the coupled-line elements. Simulated application of this technique to a 3-pole superconducting microstrip combline bandpass filter with half-wavelength resonators, a 5.0-GHz center frequency, and a 120-MHz 3-dB bandwidth shifted the bandwidth 500 MHz. However, the 3-dB bandwidth was reduced about 14 MHz. Use of a modified 3-pole microstrip interdigital bandpass filter mitigated the reduction to 2 MHz. Using this modified filter with additional electric pads is thus an effective way to tune the center frequency of HTS bandpass filters without significantly changing the bandwidth.

We have developed a bandwidth tuning method for use in high-temperature superconducting (HTS) microstrip filters. Several H-shaped waveguides are placed between the resonators, and the bandwidth is adjusted by changing the switch states of the waveguides. The coupling coefficients between the resonators are controlled by switching the connection or isolation of the center gaps of the waveguides so as to tune the bandwidth. The effects of using this method were evaluated by simulation using a filter composed of 3-pole half-wavelength straight-line resonators with an H-shaped waveguide between each pair and additional electric pads for post-tuning trimming. The filter was designed to have a center frequency of 5 GHz and a bandwidth of 100 MHz by using an electromagnetic simulator based on the moment method. The simulation showed that bandwidth tuning of 150 MHz can be obtained by using H-shaped waveguides to adjust the coupling coefficients. It also showed that using additional electric pads around the feed lines, which was previously shown to be useful for trimming to improve insertion loss after center-frequency tuning, is also useful for bandwidth tuning.

A heavy ion beam probe (HIBP) using a 3-MV tandem accelerator has been installed on large helical device (LHD). Electrostatic potential in core plasma can be measured under the toroidal magnetic field strength of up to 3 T. By using the HIBP, the transition of potential profiles from electron-root to ion-root is observed in core plasmas during ramp-up of the electron density. Potential fluctuations are also measured electron cyclotron current drive (ECCD). Two kind of characteristic fluctuations are observed. One is a reversed-shear-induced Alfven eigenmode (RSAE), whose frequency varies during the evolution of the rotational transform profile, and the other is with a constant geodeisc acoustic mode (GAM) frequency.

The Permanent Magnet method for measuring critical current density in high-temperature superconducting thin film is numerically and experimentally investigated. Numerical results show that the critical current density is approximately proportional to the maximum repulsive force. Furthermore, the maximum repulsive force increases as the value of diameter of permanent magnet increases. These tendency is also observed in the experimental investigation. Finally, the spatial distributions of the shielding current density are reproduced by the system experimentally.

We designed a 5 GHz miniaturized 10-pole Chebyshev-type bandpass filter (BPF) using superconducting microstrip quasi-spiral resonators (QSR) for international mobile telecommunication (IMT)-advanced receiving applications. When we considered the unloaded quality factor (Qu) of QSR, we found that a 10-pole QSR BPF using single-sided films and a 17-pole QSR BPF using double-sided films can be achieved an insertion loss in simulation of than 0.5 dB. The 10-pole QSR filter was fabricated using a 300 nm thick single-sided MgB2 film on a c-sapphire substrate by a thermal co-evaporation method. The Au ground plane of the filter was deposited on the other side of the substrate. Simulation and measurement profile data obtained from the passband were in close agreement. We found that the power-handling performance was equivalent to that of other miniaturized filters. We could design multi-pole filters using QSR.

We investigated the third-order intermodulation distortion (IMD3) properties of high- temperature superconducting (HTS) filters with sliced microstrip line resonators. Electromagnetic simulations indicated that the current concentration along the outer edges of a sliced microstrip line was lower than that of a conventional microstrip line. We fabricated a 3-pole filter with a sliced microstrip line resonator using HTS YBCO thin films and measured the IMD3. Until the input power increase to 7 W, the filter has proper operation from 50 to 77.3 K. The third-order intercept point value of 64 dBm was observed at 70 K. The ΔIMD3 was less than −55 dBc at 1 W input power when the temperature was 50–77.3 K. The sliced microstrip line indicated low ΔIMD3 to the fundamental two-tone sinusoidal waves, which had a difference of 1 MHz, when the input power was 1 W. The results showed that HTS filters with sliced microstrip line resonators have better power handling capability and can feasibly be used in transmitters.

We have developed a method using additional electric pads for trimming tunable high-temperature superconducting (HTS) microstrip filters. These filters are generally tuned by adjusting the gap between a dielectric floating plate above the filter. When the floating plate approached the filter, the center frequency was shifted to a lower frequency. However, the insertion loss increases due to variation in the external quality factors varying from the design parameter. The external quality factors are usually controlled by adjusting the length of the input/output (I/O) coupled-line elements and the gap between the elements and the resonator. In our method, additional electric pads are distributed at the open-end of the I/O coupled-line elements of a 3-pole hairpin bandpass filter to enable adjustment of the external quality factors so as to reduce insertion loss. The electric pads consist of line-and-space patterns. They are eclectically connected to the coupled-line elements to adjust the line length and gap width and thereby control the external quality factors. An electromagnetic simulator was used for the design and analysis. The simulation results showed that the additional electric pads are effective in improving the insertion loss of the HTS bandpass filter after tuning.

We designed and fabricated a transmit band pass filter (BPF) using circle-type high temperature superconductor (HTS) bulk resonators. A Dy–Ba–Cu–O bulk was fabricated using a modified quench and melt growth (QMG) process and cut into specimens of 8.40 and 8.44 mm in diameter and 0.5 mm thick for use as the HTS bulk resonators. A three-pole stripline (SL) BPF was designed based on a Chebyshev function and the frequency response and electromagnetic field of the filter were simulated using a three-dimensional electromagnetic field simulator. From the results of the simulation, the center frequency, bandwidth, insertion loss, and ripple of the designed filter were 4.97 GHz, 100 MHz, 0.03 dB, and 0.048 dB, respectively. In the experimental results on the actual fabricated filter, the filtering response was clearly observed; however, the center frequency of 5.46 GHz was higher than that of the simulation. The simulated maximum surface current in the resonators of the SL filter was approximately 86% smaller than that of a conventional hairpin filter. Furthermore, the measured response of the Dy–Ba–Cu–O bulk filter at an input power of 20 dBm was almost the same as that at 0 dBm. These results mean that an SL filter using a Dy–Ba–Cu–O bulk resonator may be practicable as a high-power transmit BPF.

A transmit band pass filter using circular-disk high-temperature superconductor (HTS) bulk resonators was designed with a 5.0 GHz center frequency and a 100 MHz bandwidth for use in international mobile telecommunication (IMT) advanced applications. The frequency response and electromagnetic field were calculated using a three-dimensional simulator. The mode of the resonator was used because it had the smallest diameter. Using stripline (SL) resonators enhanced both the unloaded quality factor and the coupling between the input/output ports and resonators. The frequency response of the designed SL 3-pole Chebyshev filter meets the requirements of IMT-Advanced applications. Additionally, the maximum surface current of the HTS bulk filter was approximately 86% less than that of a conventional hairpin filter.

We propose a miniaturized novel microstrip quasi-spiral resonator (QSR) system composed of rewound-type spiral resonator and c-type spiral resonator. We have also designed a 5 GHz superconducting 4-pole bandpass filter (BPF) using QSR for international mobile telecommunication (IMT)-advanced base station receiver applications. The filter has been fabricated using a single-sided MgB2 superconducting thin film deposited by thermal co-evaporation technique. The measured performance of the BPF has been found to show close agreement with the simulated one.

A vibrating normal pick-up coil coupled to a superconducting quantum interference device (SQUID) magnetometer as a nondestructive testing system was studied. The vibrating normal pick-up coil measures the magnetic field gradient at a point. Output of the SQUID magnetometer is lock-in detected at the vibration frequency. The frequency of an excitation magnetic field can be set low to detect deep structural flaws. The use of a normal coil vibrated at 20 kHz with output voltage amplified by a low-noise amplifier enabled detection of a cylindrical defect in an aluminum plate with an excitation magnetic field at 40 Hz.

A method to measure magnetic field fluctuation using a heavy ion beam probe for a toroidal magnetically confined plasma is proposed by providing a mathematical formula to connect the probing beam movement with the change in the magnetic field. The first challenge of the method has been faced in an electron-cyclotron resonance heated plasma in the compact helical system (CHS). The results reveal the existence of three characteristic frequency regimes of the magnetic field fluctuations: a low frequency regime showing a long-distance correlation, an intermediate frequency regime obeying a power law and the turbulence regime. Discussion is held on the degree of the contaminations in the local magnetic field fluctuation that are caused by the magnetic field fluctuations integrated along the beam orbit and the local electric field fluctuations.

The authors have demonstrated optical frequency synthesis using a fiber-based frequency comb system, referenced to an ultrastable microwave oscillator. The oscillator is based on a high Q-factor cryogenic sapphire resonator cooled with liquid helium. The 100-MHz signal synthesized from the 10.8-GHz oscillation frequency of the cryogenic sapphire oscillator (CSO) was used to stabilize the repetition frequency of the mode-locked fiber laser. When the synthesized optical frequency was compared with a rubidium two-photon stabilized laser at 778 nm, the measured fractional frequency stability was ~6 10-14 tau -12 for the averaging times tau between 1 and 100 s, and the best frequency stability was 3.0 10-15 for an averaging time of 1280 s

Various types of transport barriers have been studied in the Compact Helical System. In addition to the neoclassical transport barrier, the edge transport barrier (H-mode) was studied using the high-power heating of two coinjection neutral beam injections. A density pedestal is formed after the transition that is indicated by the drop of H α emission signal. The heating power threshold for the transition was investigated by varying the heating power. Its dependence on the density and the magnetic field is close to the H-mode scaling obtained in tokamaks. The dependence of the power threshold on the magnetic field configuration was also found. Local density fluctuation was measured with beam emission spectroscopy, which observed harmonic oscillations appearing after the density pedestal was formed. For L-mode plasma, long-distance coherence of the potential fluctuations were measured with two sets of heavy ion beam probes (HIBPs). Those coherent modes are supposed to be the geodesic acoustic mode part of zonal flow. Turbulent particle flux was also measured with HIBP, and its change with internal transport barrier formation is demonstrated.