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New polarizer and launcher systems on a 28-GHz electron-cyclotron (EC) heating and current drive (HCD) system have been developed for non-inductive second-harmonic EC-plasma-current ramp-up in the QUEST spherical tokamak. A launcher system with two quasi-optical mirrors providing beam steering capability was designed to focus the incident beam to a small-sized waist of ∼0.05 m at the second-harmonic EC resonance layer. A relatively large focusing mirror was designed based on a Kirchhoff integral code developed to derive wave solutions. The focusing property of the launched beam was first confirmed with a 3-dimensional (3D) electromagnetic-wave simulator. Focusing characteristics were also checked at low-power test facilities, together with the steering capability. The performance of this launcher system was demonstrated to work as designed, and assembled in the QUEST device. The system was applied to the non-inductive second-harmonic EC plasma ramp-up experiments with no optimization required regarding the incident polarization. The results obtained for the non-inductive plasma ramp-up are also presented.

Steady-state fusion reactor operation presents major divertor technology challenges, including high divertor heat flux both steady-state and transients. In addition, there are unresolved issues of long term dust accumulation and associated tritium inventory and safety concerns (Federici et al., 2001) [1] . It has been suggested that radiative liquid lithium divertor concepts with a modest lithium-loop could provide a possible solution for these outstanding fusion reactor technology issues, while potentially improving reactor plasma performance (Ono et al., 2013, 2014) [2] , [3] . The application of lithium (Li) in NSTX resulted in improved H-mode confinement, H-mode power threshold reduction, and reduction in the divertor peak heat flux while maintaining essentially Li-free core plasma operation even during H-modes. These promising results in NSTX and related modeling calculations motivated the radiative liquid lithium (LL) divertor (RLLD) concept (Ono et al., 2013) [2] and its variant, the active liquid lithium divertor concept (ARLLD) (Ono et al., 2014) [3] , taking advantage of the enhanced non-coronal Li radiation in relatively poorly confined divertor plasmas. It was estimated that only a few moles/s of lithium injection would be needed to significantly reduce the divertor heat flux in a tokamak fusion power plant. By operating at lower temperatures ≤450 °C than the first wall ∼600–700 °C, the LL-covered divertor chamber wall surfaces can serve as an effective particle pump, as impurities generally migrate toward lower temperature LL divertor surfaces. To maintain the LL purity, a closed LL loop system with a modest circulating capacity of ∼1 l/s (l/s) is envisioned to sustain the steady-state operation of a 1 GW-electric class fusion power plant. By running the Li loop continuously, it can carry the dust particles and impurities generated in the vacuum vessel to outside where the dust/impurities are removed by relatively simple filter and cold/hot trap systems. Using a cold trap system, it can recover tritium (T) in real time from LL at a rate of ∼0.5 g/s needed to sustain the fusion reaction while minimizing the T inventory. With an expected T fraction of ≤0.7%, an acceptable T inventory level can be achieved. In NSTX-U (Menard et al., 2012; Ono et al., 2015) [4,5], preparations are now underway to elucidate the physics of Li plasma interactions with a number of Li application tools and Li radiation spectroscopic instruments. The NSTX-U Li evaporator, which provides Li coating over the lower divertor plate, can offer important information on the RLLD concept, and the Li granule injector will test some of the key physics issues for the ARLLD concept. A LL loop is also being prepared off-line for prototyping future use on NSTX-U.

A series of first-of-a-kind laboratory-scale experiments on the JxB -force convected liquid metal divertor concept have been carried out in the temperature range from room temperature to ∼200 °C, employing a eutectic alloy: Ga 67 In 20.5 Sn 12.5 , the melting point of which is 10.5 °C. The electrical current conducted through the alloy is set at about 70A and the magnetic field is set at about 700 G. It has reproducibly been observed that hydrogen as well as helium particle recycling is noticeably reduced under steady state plasma bombardment when the liquid is convected by the JxB force.

The Telescope Array experiment studies ultra high energy cosmic rays using a hybrid detector. Fluorescence telescopes measure the longitudinal development of the extensive air shower generated when a primary cosmic ray particle interacts with the atmosphere. Meanwhile, scintillator detectors measure the lateral distribution of secondary shower particles that hit the ground. The Middle Drum (MD) fluorescence telescope station consists of 14 telescopes from the High Resolution Fly’s Eye (HiRes) experiment, providing a direct link back to the HiRes measurements. Using the scintillator detector data in conjunction with the telescope data improves the geometrical reconstruction of the showers significantly, and hence, provides a more accurate reconstruction of the energy of the primary particle. The Middle Drum hybrid spectrum is presented and compared to that measured by the Middle Drum station in monocular mode. Further, the hybrid data establishes a link between the Middle Drum data and the surface array. A comparison between the Middle Drum hybrid energy spectrum and scintillator Surface Detector (SD) spectrum is also shown.

For improved core performance via edge plasma-wall boundary control, solid and liquid lithium has been used as a plasma-facing material in a number of confinement experiments over the past several decades. Unfortunately, it is unavoidable that lithium is saturated in the surface region with implanted hydrogenic species as well as oxygen-containing impurities. For steady state operation, a flowing liquid lithium divertor with forced convection would probably be required. In the present work, the effects of liquid stirring to simulate forced convection have been investigated on the behavior of hydrogen and helium recycling from molten lithium at temperatures up to ∼350 °C. Data indicate that liquid stirring reactivates hydrogen pumping via surface de-saturation and/or uncovering impurity films, but can also induce helium release via surface temperature change.

Developing a reactor compatible divertor has been identified as a particularly challenging technology problem for magnetic confinement fusion. Application of lithium (Li) in NSTX resulted in improved H-mode confinement, H-mode power threshold reduction, and reduction in the divertor peak heat flux while maintaining essentially Li-free core plasma operation even during H-modes. These promising Li results in NSTX and related modeling calculations motivated the radiative liquid lithium divertor (RLLD) concept [1] . In the RLLD, Li is evaporated from the liquid lithium (LL) coated divertor strike point surface due to the intense heat flux. The evaporated Li is readily ionized by the plasma due to its low ionization energy, and the poor Li particle confinement near the divertor plate enables ionized Li ions to radiate strongly, resulting in a significant reduction in the divertor heat flux. This radiative process has the desired effect of spreading the localized divertor heat load to the rest of the divertor chamber wall surfaces, facilitating divertor heat removal. The modeling results indicated that the Li radiation can be quite strong, so that only a small amount of Li (∼a few mol/s) is needed to significantly reduce the divertor peak heat flux for typical reactor parameters. In this paper, we examine an active version of the RLLD, which we term ARLLD, where LL is injected in the upstream region of divertor. We find that the ARLLD has similar effectiveness in reducing the divertor heat flux as the RLLD, again requiring only a few mol/s of LL to significantly reduce the divertor peak heat flux for a reactor. An advantage of the ARLLD is that one can inject LL proactively even in a feedback mode to insure the divertor peak heat flux remains below an acceptable level, providing the first line of defense against excessive divertor heat loads which could result in damage to divertor PFCs. Moreover, the low confinement property of the divertor (i.e.

Deuterium fueling experiments were conducted with the NSTX Liquid Lithium Divertor (LLD). Lithium evaporation recoated the LLD surface to approximate flowing liquid Li to sustain D retention. In the first experiment with the diverted outer strike point on the LLD, the difference between the applied D gas input and the plasma D content reached very high values without disrupting the plasma, as would normally occur in the absence of Li pumping, and there was also little change in plasma D content. In the second experiment, constant fueling was applied, as the LLD temperature was varied to change the surface from solid to liquid. The D retention was relatively constant, and about the same as that for solid Li coatings on graphite, or twice that achieved without Li PFC coatings. Contamination of the LLD surface was also possible due to compound formation and erosion and redeposition from carbon PFCs.

Lithium wall coating techniques have been experimentally explored on National Spherical Torus Experiment (NSTX) for the last six years. The lithium experimentation on NSTX started with a few milligrams of lithium injected into the plasma as pellets and it has evolved to a dual lithium evaporation system which can evaporate up to ∼160 g of lithium onto the lower divertor plates between re-loadings. The unique feature of the NSTX lithium research program is that it can investigate the effects of lithium coated plasma-facing components in H-mode divertor plasmas. This lithium evaporation system has produced many intriguing and potentially important results. In 2010, the NSTX lithium program has focused on the effects of liquid lithium divertor (LLD) surfaces including the divertor heat load, deuterium pumping, impurity control, electron thermal confinement, H-mode pedestal physics, and enhanced plasma performance. To fill the LLD with lithium, 1300 g of lithium was evaporated into the NSTX vacuum vessel during the 2010 operations. The routine use of lithium in 2010 has significantly improved the plasma shot availability resulting in a record number of plasma shots in any given year. In this paper, as a follow-on paper from the 1st lithium symposium [1] , we review the recent progress toward developing fundamental understanding of the NSTX lithium experimental observations as well as the opportunities and associated R&D required for use of lithium in future magnetic fusion facilities including ITER.

NSTX 2010 experiments were conducted using a molybdenum Liquid Lithium Divertor (LLD) surface installed on the outer part of the lower divertor. This tested the effectiveness of maintaining the deuterium retention properties of a static liquid lithium surface when refreshed by lithium evaporation as an approximation to a flowing liquid lithium surface. The LLD molybdenum front face has a 45% porosity to provide sufficient wetting to spread 37 g of lithium, and to retain it in the presence of magnetic forces. Lithium Evaporators were used to deposit lithium on the LLD surface. At the beginning of discharges, the LLD lithium surface ranged from solid to liquefied depending on the amount of applied and plasma heating. Noteworthy improvements in plasma performance were obtained similar to those obtained previously with lithiated graphite, e.g., ELM-free, quiescent edge, H-modes. During these experiments with the plasma outer strike point on the LLD, the rate of deuterium retention in the LLD, as indicated by the fueling needed to achieve and maintain stable plasma conditions, was the about the same as that for solid lithium coatings on the graphite prior to the installation of the LLD, i.e., about two times that of no-lithium conditions. The role of lithium impurities in this result is discussed. Following the 2010 experimental campaign, inspection of the LLD found mechanical damage to the plate supports, and other hardware resulting from forces following plasma current disruptions. The LLD was removed, upgraded, and reinstalled. A row of molybdenum tiles was installed inboard of the LLD for 2011 experiments with both inner and outer strike points on lithiated molybdenum to allow investigation of lithium plasma facing issues encountered in the first testing of the LLD.

Lithium wall coating techniques have been experimentally explored on NSTX for the last five years. The lithium experimentation on NSTX started with a few milligrams of lithium injected into the plasma as pellets and it has evolved to a lithium evaporation system which can evaporate up to ~ 100 g of lithium onto the lower divertor plates between lithium reloadings. The unique feature of the lithium research program on NSTX is that it can investigate the effects of lithium in H-mode divertor plasmas. This lithium evaporation system thus far has produced many intriguing and potentially important results; the latest of these are summarized in a companion paper by H. Kugel. In this paper, we suggest possible implications and applications of the NSTX lithium results on the magnetic fusion research which include electron and global energy confinement improvements, MHD stability enhancement at high beta, ELM control, H-mode power threshold reduction, improvements in radio frequency heating and non-inductive plasma start-up performance, innovative divertor solutions and improved operational efficiency.

NSTX high power divertor plasma experiments have used in succession lithium pellet injection (LPI), evaporated lithium, and injected lithium powder to apply lithium coatings to graphite plasma facing components. In 2005, following the wall conditioning and LPI, discharges exhibited edge density reduction and performance improvements. Since 2006, first one, and now two lithium evaporators have been used routinely to evaporate lithium onto the lower divertor region at total rates of 10-70 mg/min for periods 5-10 min between discharges. Prior to each discharge, the evaporators are withdrawn behind shutters. Significant improvements in the performance of NBI heated divertor discharges resulting from these lithium depositions were observed. These evaporators are now used for more than 80% of NSTX discharges. Initial work with injecting fine lithium powder into the edge of NBI heated deuterium discharges yielded comparable changes in performance. Several operational issues encountered with lithium wall conditions, and the special procedures needed for vessel entry are discussed. The next step in this work is installation of a liquid lithium divertor surface on the outer part of the lower divertor.

The effect of the strong centrifugal force, mega-gravity (MG) on inter-diffusion between Au and Cu thin films was studied by using Au(60 nm)/Cu(500 nm)/α-Al2O3 (0 0 0 1) films. The Rutherford backscattering analysis of the Au and Cu depth profiles shows that Cu atoms diffuse through the Au layer, resulting in the formation of the Cu layer on the surface under both the thermal annealing at 220 °C and the application of 0.61 × 106 G at 220 °C. The results indicate that the MG application enhances the layer thickness of the Cu layer on the surface.

One of the programs in the Ministry of Economy and Trade and Industry (METI) project regarding R & D on YBCO conductor is to evaluate the applicability of the developed conductor toward several applications. This paper focuses on a fault current limiter (FCL) as one of the expected power applications. YBCO tape conductors with ion beam assisted deposition (IBAD) substrate are used in this work. In order to obtain high resistance of the conductor, which is preferable to an FCL, the thickness of the protecting layer made of silver was decreased as possible. Then high-resistive metal stabilizing layer is attached on the silver layer to improve stability. Obtaining the relevant current limiting performance on short sample experiments, model coils were developed to aim the 6.6 kV-class FCL. Short circuit experiments were implemented with a short circuit generator. The coil successfully restricted the short circuit current over 17 kA to about 700 A by the applied voltage of 3.8 kV, which is nominal phase-to-ground voltage. The experimental results show good agreement with computer analyses and show promising toward the application.

Titanium oxide films grown on Ag(100) have been investigated with low-energy electron diffraction, X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy. As Ti is deposited on Ag(100) at room temperature in an O 2 atmosphere at 10 −5 –10 −7 Torr, a disordered TiO 2 -like film is formed. As the surface is subsequently heated at 600 ∘ C, though the composition of the film is nearly unchanged, the film changes into an ordered film with (5×1) periodicity [(5×1) TiO 2 film]. On the other hand, as Ti is deposited in O 2 at 5.0×10 −9 –1.0×10 −8 Torr, a disordered TiO-like film is formed. As the surface is subsequently heated at 600 ∘ C, the composition of the film is nearly unchanged and the film changes into an ordered film with (1×1) periodicity [(1×1) TiO film]. Ultraviolet photoelectron spectroscopy measurements show that the (1×1) TiO film has an electronic state around the Fermi level, and the state is ascribed to a partially filled Ti 3d state which has been theoretically expected to exist in a TiO crystal.

We performed a design study of sextupole magnet using high temperature superconducting (HTS) wires. The sextupole magnet is used as a focusing lens for neutron-focusing devices. A neutron-focusing device is desired to have a large aperture and a high magnetic field gradient of G , where G = 2 B / r 2 , B is the magnetic field and r is a distance from the sextupole magnet axis. Superconducting magnets offer promising prospects to meet the demands of a neutron-focusing device. Recently NbTi coils of low temperature superconducting (LTS) have been developed for a sextupole magnet with a 46.8 mm aperture. The maximum magnetic field gradient G of this magnet is 9480 T/m 2 at 4.2 K and 12,800 T/m 2 at 1.8 K. On the other hand, rapid progress on second generation HTS wire has been made in increasing the performance of critical current and in demonstrating a long length. The second generation HTS wire is referred to as coated conductor. It consists of tape-shaped base upon which a thin coating of superconductor, usually YBCO, is deposited or grown. This paper describes a design study of sextupole magnet using coated conductors.

As part of our ongoing search for flavonoids that are bioactive in humans, it was determined that FRS 1000, a beverage containing flavonoids extracted from onion peel, showed unexpected improvement of male sexual function. An in vitro enzyme assay clearly showed that FRS 1000 has a strong phosphodiesterase 5A (PDE 5A) inhibitory activity, which is considered to be important for treatment of erectile dysfunction. Detailed assays of each major ingredient indicated that the antioxidative flavonoid quercetin was responsible for the activity. Results also suggested that PDE 5A inhibition is not directly related to the free radical scavenging activity of flavonoids.

Drug release behavior was investigated for tablets of a ternary system in which metoprolol tartrate (Met)/2-hydroxypropyl-β-cyclodextrin (HP-β-CD) complexes with different molar ratios were dispersed in an ethylcellulose (EC) matrix. The release rate of Met from the tablets decreased due to the formation of the binary solid dispersion with EC and was further slowed down by dispersal of the Met/HP-β-CD complex in the EC matrix. The release rate of Met decreased with the increase in contents of HP-β-CyD in EC matrix up to (30/10)/60%w/w (Met/HP-β-CD)/EC but further increases in HP-β-CD content led to faster release rates. The analysis of the release rates by Korsmeyer's and Higuchi's equations and their temperature dependence suggested that Met is released according to a diffusion-controlled mechanism. Water penetration studies and microscopic observation suggested that the retarding effect of HP-β-CD is attributable to a gel formation in small pores of the EC matrix. Moreover, the release rate of Met from the ternary (Met/HP-β-CD)/EC ((30/10)/60%w/w) tablet was negligibly influenced by the pH of the dissolution medium, paddle rotation rate, viscosity of the solution and storage conditions of the tablet. The results suggested that HP-β-CD can work as a release rate-decelerating agent for Met when it is formulated in appropriate amounts in a hydrophobic EC matrix. Therefore, a combination of HP-β-CD and EC may be useful for the controlled release of water-soluble drugs, and the release control can be tuned by adjusting the composition of components.

Studies are underway to identify and characterize a design point for a next step spherical torus (NSST) experiment. This would be a ‘proof of performance’ device which would follow and build upon the successes of the national spherical torus experiment (NSTX) ‘proof of principle’ device which has operated at PPPL since 1999. With the decontamination and decommissioning (D&D) of the tokamak fusion test reactor (TFTR) nearly completed, the TFTR test cell and facility will soon be available for a device such as NSST. By utilizing the TFTR test cell, NSST can be constructed for a relatively low cost on a short time scale. In addition, while furthering spherical torus (ST) research, this device could achieve modest fusion power gain for short pulse lengths, a significant step toward future large burning plasma devices now under discussion in the fusion community. The selected design point is Q=2 at HH=1.4, Pfusion=60 MW, 5-s pulse, with R0=1.5 m, A=1.6, Ip=10 MA, Bt=2.6 T, CS flux=16 weber. Most of the research would be conducted in DD, with a limited DT campaign during the last years of the program.

Photoion yield spectra of C 60 in the gas phase were measured from 23 to 180 eV by synchrotron radiation. Two peaks at 26 and 34 eV and a flat area ranging 40–50 eV are newly observed in the high-energy side of the giant resonance at ∼20 eV. These features are assigned to the shape resonance on photoionization of the valence electrons of C 60 ; the ionized electron is temporarily trapped inside a centrifugal barrier. Above ∼50 eV the yield curve shows a steady decrease with increasing photon energy like the photoabsorption cross section of atomic carbon. Thus, the spectrum is interpreted as essentially determined by photoionization of the 2s orbitals of carbon atoms.

Giant magnetostrictive TbFe 2 thin films were prepared by the ion plating process. The films were treated by Ar plasma irradiation and heat-treatment. The plasma irradiation was carried out at low plasma energy by a high heat flux sheet plasma system. Both treatments lead to the increase in the maximum magnetostriction and the magnetostrictive susceptibility at low magnetic field. The plasma irradiation effects seem to be due to the heat generation during irradiation. The magnetostrictive characteristics are affected by the increase in in-plane anisotropy magnetization by treatments.

The Ring-Imaging Cherenkov (RICH) and the Time-of-Flight (ToF) systems provide identification of charged particles for the PHENIX central arm. The RICH is located between the inner and outer tracking units and is one of the primary devices for identifying electrons among the very large number of charged pions. The ToF is used to identify hadrons and is located between the most outer pad chamber (PC3) and the electromagnetic calorimeter. A Time Zero (T0) counter that enhances charged particle measurements in p–p collisions is described. Details of the construction and performance of both the RICH, ToF and T0 are given along with typical results from the first PHENIX data taking run.

A project to develop a high-temperature superconducting split magnet for Si single crystal growth applications has progressed. This split coil system is composed of two coils, each consisting of 18 pancakes, and the total length of Bi2223 tapes is approximately 80 km. In last fiscal year ending 31 March, 2000, testing and evaluation of an experimental magnet, incorporating two or four pancake coils of the same size as those of the target magnet, has been accomplished. In these tests, we have demonstrated 290 A operation with generating a magnetic field of 0.41 T and accumulated energy as high as 50 kJ. No critical current degradation of these coils occurred at the hoop stress of 46 MPa, which would be applied to the target magnet. The final design of the target magnet has been completed and all the pancake coils for the magnet have been fabricated. The electric performance of each coil was tested in liquid nitrogen and each coil will be placed at the most suitable position in the magnet according to these results. This target magnet will be tested in December 2000.

The authors have developed a PC-based Synthetic Aperture Radar (SAR) image processing software for image generation from raw data, and have also developed the interferometry processing software. In this paper, we introduce and estimate our softwar's performance and show several image examples. To estimate the performance of our software, we compared processing time between our software and some commercial software. The result is that our software takes same time as the commercial software does to reconstruct the image. This SAR software is available free of charge and has been provided on RESTEC Homepage. Currently, it is available for three kinds of machines: Power Macintosh, IBM-Compatible PC and UNIX (Sun Solaris 2.X).

The space orbiting radio telescope, HALCA, was placed into highly elliptical earth orbit on February 12, 1997. A master oscillator on board is phase locked to a reference signal generated by a hydrogen maser frequency standard in a ground tracking station. The frequency and the phase of the satellite oscillator are monitored in the ground tracking station. This paper provides a brief summary of the phase transfer link and gives the stability of the phase transfer link before and after the launch. Also this paper gives the discussions on the atmospheric phase fluctuations and the statistical property.

We have developed a synthetic route for (2 S ,3 R )- and (2 S ,3 S )-[2- 13 C;3- 2 H] glutamic acids with high enantioselectivity. The key reactions in this synthesis are the asymmetric reduction of the 2,3-didehydroornithine derivative using the ( S , S )-Et-DuPHOS-Rh catalyst and the oxidation of the δ-position by ruthenium catalysis.

We (Asahi Chemical Industy Co., Ltd.) have developed a technology for a highly selective partial hydrogenation of benzene to cyclohexene and succeeded in the commercialization of a new production process for producing cyclohexanol from benzene through cyclohexene. The process has been considered to be difficult for a long time in the industry. Several innovative technologies made the partial hydrogenation reaction possible. A catalyst that consists of specific metallic ruthenium particles exhibited excellent high selectivity of cyclohexene. The catalyst was obtained by reducing a ruthenium compound which contains a zinc compound. The use of a zinc of strong acid as a co-catalyst exhibited a remarkable effect to enhance selectivity. Dispersing agents of metal oxides were found to extend the life of the metallic ruthenium catalyst and some dispersing agents had the effect of enhancing the selectivity in the partial hydrogenation reaction. One of the remarkable features of the reaction was the reaction field. This comprises four phases: vapor (hydrogen), oil, aqueous and solid (ruthenium catalyst). The catalyst was used in the aqueous phase, and the reactants (benzene and hydrogen) were dissolved in the aqueous phase where the reaction proceeded. Therefore the products and reactants transfer between four phases through dissolution, diffusion and extraction, rendering quick transfer was a very important factor in enhancing reaction selectivity. The catalyst system and the reaction field described above made the selectivity for cyclohexene very high, and a yield of 60% for cyclohexene was obtained.

In metal matrix composites (MMCs) internal stresses to be induced by changes in temperature as a result of unequal coefficients of thermal expansion (CTEs) of matrix and reinforcement can have various effects on macromechanical behavior of MMCs. In this study neutron diffraction has been used to determine stresses in a quenched SiC/Al particulate composite.

The quartz friction vacuum gauge is based on pressure dependence of the resonance electric impedance of a miniature quartz oscillator of tuning fork shape. The results of the theoretical and the experimental studies clarified the properties of the gauge for various pure gases in the pressure range 10 −3 Pa to 1 atm. An algorithm, introduced in this study for calculating the pressure as a function of the impedance, improved the accuracy of pressure readings of the gauge and made it possible to analyze a binary mixture of gases. Pressure dependence of the resonance frequency of the oscillator was adopted as an additional quantity, depending on kinds of gases, and utilized to measure the pressure during purging of a vacuum chamber with hydrogen. An analysis with the gauge of a mixture of argon and helium was tested successfully for practical monitoring of concentration in the pressure range 1 atm to 1 Pa.

Ku is a ubiquitous and abundant DNA binding protein. Recently, it has been shown that Ku plays a crucial role in double stranded-DNA (dsDNA) break repair such as occurs during the V(D)J recombination of Ig genes. Ku has also been found to provide DNA binding activity to the catalytic domain of DNA-PK which is known to phosphorylate several transcription factors, suggesting that Ku is a multifunctional protein that participates as a component of several functional DNA-protein complexes. Here, we examined the interaction of Ku with several DNA binding proteins. Firstly, the DNA binding interaction between Ku and well-characterized transcription factors (OTF-1, Sp-1, AP-1) was analysed by EMSA. Although sequence non-specific, Ku was strongly competitive with these sequence specific transcription factors on compatible DNA elements, displacing them because of its high affinity association with DNA ends. Secondly, to determine whether this competitive effect was functionally relevant, we tested Ku in an in vitro transcription system with the adenovirus major late promoter. We found that Ku inhibited transcription from linear, but not from circular template DNA. These results suggest that Ku inhibits transcription when it is able to bind to template DNA and that the inhibition is the result of Ku displacing specific transcription factors from DNA.

Low aspect-ratio tokamaks (LARTs) have intrinsic features which require specific diagnostics for particle transport and confinement studies. Such spectroscopic diagnostics are developed in collaboration between the CDX-U group at Princeton Plasma Physics Laboratory and the Plasma Spectroscopy group at Johns Hopkins University. This paper presents results obtained from the low aspect-ratio CDX-U tokamak, as well as future diagnostic developments for CDX-U and other LARTs. These results are based on spectroscopy in the VUV (500 A - 2000 A) using a multiple grating normal incidence spectrometer equipped with an optical multichannel analyzer, and in the XUV range on emission recorded using multilayer mirror devices.

The relationship between stability of superconductor and structure of the cable-in-conduit (CIC)-type conductor is discussed by studying the simple estimation of work by strand movement and results of stability tests of small coils wound by five kinds of CIC-type NbTi conductors. The allowable thermal disturbance energy not to quench the coil is estimated. When the strands are electrically insulated, the stability of the CIC-type conductor is low because of inhomogeneous current distribution among the strands. On the other hand, when the strands are not insulated, the conductors are stable until the thermal disturbance energy approaches the helium enthalpy rise from bath temperature to the temperature of current sharing because of quick current transfer to other strands.

SUMMARY A case of histologically benign cardiac and pulmonary metastases from a uterine leiomyoma in a 45-year-old woman is reported. The solitary cardiac tumor consisted of five lobules with a stalk attached to the anterior papillary muscle of the right ventricle, which occupied the right ventricular cavity and almost completely- obstructed the pulmonary main trunk in the systolic cycle. Multiple small nodules were found throughout both lungs. The cardiac tumor was resected at open heart surgery and open lung biopsy of the pulmonary lesion was simultaneously performed. Both of them were histologically identical to the apparently histologically benign uterine leiomyoma which had been resected five years previously. Based on the clinical and laboratory findings, it is postulated that antegrade metastases via the venous system resulted in the cardiac metastasis from the uterine leiomyoma and the secondary pulmonary metastasis from the cardiac tumor. In contrast to the light microscopic findings, ultrastructural examination suggested the possibility of malignancy associated with the presence of immature smooth muscle cells. This is the first reported case of a so-called benign metastasizing leiomyoma occurring in the heart.