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To observe nonlinearity in the stopping power of a nonideal plasma for heavy ions, we are planning a beam-plasma interaction experiment using 10-100 keV/u projectiles. For the interaction experiment, a nonideal hydrogen plasma target was developed by means of a shock technique. Time-resolved spectroscopic measurements determined the temporal evolution of the electron density and temperature of the shock plasma. These data revealed that the structure behind the shock front has an appropriate spatial and temporal distribution to be used as a target. We also evaluated the temporal evolution of the Coulomb coupling constant and the degree of ionization at a fixed position where the projectiles are injected. We discuss the feasibility of the nonlinear stopping experiment by evaluating the beam-plasma coupling constant expected from the measured plasma parameters. [ABSTRACT FROM AUTHOR]

The ion-production efficiency of a newly developed singly charged ion source (SCIS) has been investigated to discuss the possibility of it being used in an isotope separation on-line system that provides 11C ions for heavy-ion cancer therapy with simultaneous verification of the irradiation field using positron emission tomography. The SCIS uses a low-energy hollow electron beam to produce singly charged carbon ions efficiently. To deliver sufficient 11C ions to the treatment room from a limited amount of 11C molecules, which are produced from a boron compound target and proton-beam irradiation via the 11B(p,n)11C reaction, the SCIS must have high ion-production efficiency. To realize this high efficiency, the SCIS was designed using a three-dimensional particle-in-cell code in previous work. With the fabricated SCIS, we performed experiments to measure the efficiency of producing C O 2 + ions from nonradioactive 12CO2 molecules and C+ ions from nonradioactive 12CH4 molecules. We found that the SCIS achieved efficiencies of ε C + = 4 × 1 0 − 3 (0.4%) for C+ production and ε C O 2 + = 0.107 (10.7%) for C O 2 + production. [ABSTRACT FROM AUTHOR]

Presents a study which clarified the relationship between the martensitic transformation and the strain effect in bronze-processed multifilamentary Nb[sub3]Sn superconducting wires. Details of the strain effects on critical current density for pure Nb[sub3]Sn and titanium-added (Nb, Ti)[sub3]Sn wires; Details of the experiment; Calculation of the residual strain in bronze-processed multifilamentary Nb[sub3]Sn superconducting wires.

A singly charged ion source (SCIS) has been designed using a newly developed three-dimensional particle-in-cell (PIC) code. The SCIS is to be used in an isotope separation on-line (ISOL) system that provides 11C ions for heavy-ion cancer therapy with simultaneous verification of the dose distribution using positron emission tomography. The SCIS uses low-energy electron beams to produce singly charged carbon ions efficiently and maintain a high vacuum in the ISOL system. Because the SCIS has to realize a production efficiency of 1% if its carbon ions are to be used in the ISOL system, a suitable design for the SCIS was investigated by using the developed PIC code to study the beam trajectories of the electrons and extracted ions. The simulation results show that hollow electron beams are produced in the designed SCIS resulting in a high effective electron current. The results also predict that the designed SCIS would realize ion-production efficiencies (IPEs) of εSCIS ≃ 6.7% for C O 2 + production from CO2 gas and εSCIS ≃ 0.1% for C+ production from CH4 gas. Moreover, to examine the validity of the developed code and confirm that the SCIS was able to be designed appropriately, the space-charge-limited current of the electron gun and the total IPE obtained by adding the IPEs of each ion were compared between the experiment and the simulation. [ABSTRACT FROM AUTHOR]

A new singly charged ion source using electron impact ionization has been developed to realize an isotope separation on-line system for simultaneous positron emission tomography imaging and heavy-ion cancer therapy using radioactive 11C ion beams. Low-energy electron beams are used in the electron impact ion source to produce singly charged ions. Ionization efficiency was calculated in order to decide the geometric parameters of the ion source and to determine the required electron emission current for obtaining high ionization efficiency. Based on these considerations, the singly charged ion source was designed and fabricated. In testing, the fabricated ion source was found to have favorable performance as a singly charged ion source. [ABSTRACT FROM AUTHOR]

A 11C molecular production/separation system (CMPS) has been developed as part of an isotope separation on line system for simultaneous positron emission tomography imaging and heavy-ion cancer therapy using radioactive 11C ion beams. In the ISOL system, 11CH4 molecules will be produced by proton irradiation and separated from residual air impurities and impurities produced during the irradiation. The CMPS includes two cryogenic traps to separate specific molecules selectively from impurities by using vapor pressure differences among the molecular species. To investigate the fundamental performance of the CMPS, we performed separation experiments with non-radioactive 12CH4 gases, which can simulate the chemical characteristics of 11CH4 gases. We investigated the separation of CH4 molecules from impurities, which will be present as residual gases and are expected to be difficult to separate because the vapor pressure of air molecules is close to that of CH4. We determined the collection/separation efficiencies of the CMPS for various amounts of air impurities and found desirable operating conditions for the CMPS to be used as a molecular separation device in our ISOL system. [ABSTRACT FROM AUTHOR]

Abstract: Multiple-energy synchrotron operation providing carbon-ion beams with various energies has been used for scanned particle therapy at NIRS. An energy range from 430 to 56MeV/u and about 200 steps within this range are required to vary the Bragg peak position for effective treatment. The treatment also demands the slow extraction of beam with highly reliable properties, such as spill, position and size, for all energies. We propose an approach to generating multiple-energy operation meeting these requirements within a short time. In this approach, the device settings at most energy steps are determined without manual adjustments by using systematic parameter tuning depending on the beam energy. Experimental verification was carried out at the HIMAC synchrotron, and its results proved that this approach can greatly reduce the adjustment period. [Copyright &y& Elsevier]

Abstract: Magnetic entropy change, ΔS M, and the refrigeration capacity, q, of MnFeP1− x Si x have been examined. In accordance with the previous report, the compounds with 0.30⩽ x ⩽0.60 undergo a first-order magnetic transition near room temperature. The Curie temperature is increased linearly from 210K to 360K with increasing x from 0.30 to 0.60. The compounds display large thermal hysteresis. This hysteresis decreases with increasing x. We have carefully estimated ΔS M of the compounds with large thermal hysteresis from the Maxwell relation using the magnetization–temperature curves. It was found the peak values of ΔS M in a field change of 2T is 7–13J/Kkg, which are much smaller than the values reported previously. On the other hand, the q values of the compounds over the temperature range 30K were found to be 1.5 times as large as that of metallic Gd. These results demonstrate excellent magnetic refrigerant capacity of MnFeP1− x Si x near room temperature. To expand the working temperature range of magnetic refrigerant materials, a design of a composite material is also proposed. [Copyright &y& Elsevier]

Abstract: In order to realize a precise dose distribution in heavy-ion cancer therapy, high beam stability is required for the accelerator complex. Owing to load fluctuation caused by the upper ring, which is one of the two rings in HIMAC, current dips of ≈5–10Hz were observed in the power supply for the bending/quadrupole magnet of the other lower ring. The parameters of the beam stability, such as the spill variation, the beam position, and the size, were adversely affected by the current dips. In order to suppress these current dips, we developed a new feed-forward system in the magnet power supply. We verified the performance of the feed-forward system by measuring the suppression of the current dips. We also performed beam experiments to measure the variation of the horizontal tune and the structure of the beam spill, which is slowly extracted by the resonance method. The experimental result showed that the current dips were successfully reduced by the system to ΔI/I ∼10−6. It was also confirmed that the horizontal tune and the spill structure could be stabilized by the current dip suppression. [Copyright &y& Elsevier]

Abstract: To date, there have been no reports showing the efficacy of nonsecosteroidal vitamin D receptor (VDR) agonists in a benign prostatic hyperplasia (BPH) animal model. To examine the efficacy of CH5036249, a novel nonsecosteroidal VDR agonist, we orally administered the compound at 0.03μg/kg to a beagle model with spontaneous BPH. Prostate volume was checked by rectal ultrasonic probe periodically during 11 months of administration and the prostate tissues histologically examined. CH5036249 inhibited prostate growth in two out of three dogs compared with vehicle-treated dogs. In the prostate specimens, substantial atrophy of the epithelium was observed in all dogs administered CH5036249. At the dose given, serum calcium levels slightly increased in the CH5036249-treated dogs but stayed within a normal range. We next examined the cell growth inhibition of CH5036249 using human prostate stromal cells and found the cell growth inhibitory activity of CH5036249 to be comparable to that of 1α,25(OH)2D3. The bioavailability from oral administration in rats was 95.1% with a t 1/2 of 17.6h. Both micro-AMES and micronucleus tests were negative. Although the results are still preliminary, we consider the novel nonsecosteroidal VDR agonist CH5036249 to be a possible new drug candidate for the treatment of BPH in humans. [ABSTRACT FROM AUTHOR]

Abstract: The strain dependence of critical current I c of a commercial RABiTS (Rolling-Assisted Biaxially Textured Substrates) YBCO coated conductor tape with Cu stabilizing layers on both surfaces has been studied by two kinds of bending apparatus and a tensile apparatus at 77K and 293K. According to the voltage measurements using multi-taps in the longitudinal direction, local I c degradation was also observed. In the continuous bending-tension test at 77K, in which YBCO layer was subjected to the tensile strain, I c began to decrease rapidly beyond the strain of 0.6% after initial moderate degradation. In the continuous bending-compression tests, the I c began to decrease rapidly beyond the strain of 0.4%. The strain for the beginning of degradation of I c obtained by tensile tests at 77K was almost the same as that by the bending-tension tests. Bending test at RT using FRP holders showed I c degradation not so different from that by the continuous bending tests at 77K. In all tests, the I c initially degraded locally irrespective of the position in the specimens. Furthermore, I c degradation by repeated bending was also studied. [Copyright &y& Elsevier]

Abstract: The tests of mechanical properties of the rare earth single grain bulk superconductors have been conducted. In this study, three-point bending high cycle fatigue tests loaded in the a/b-axis direction and the bending fatigue crack propagation tests loaded in the c-axis direction of Dy123 bulk superconductor with 25 vol.% 211 particles have been carried out at room temperature. No specimen has broken up to the number of cycles 106 at the maximum stresses less than 60MPa, the fatigue limit. This value equals approximately to 88% of the average bending strength of the bulk superconductor obtained by the three point bending tests. All the specimens subjected to cyclic stress above the fatigue limit were broken within the number of cycles of about 2×104. The threshold stress intensity factor for the crack propagation of Dy123 bulk was in the range of 0.93–1.33MPa√m. The crack propagation rate obtained during the propagation test significantly scattered. The optical microscopy showed that the fatigue crack propagated with significant deflection to a/b direction making use of pre-existing a/c or b/c cracks. This is in marked contrast with the monotonic bending test of notched specimen, in which the crack propagates in the c-axis direction with small amount of deflection. [Copyright &y& Elsevier]

Abstract: A coaxial electromagnetic shock tube was developed to produce a non-ideal plasma target with Γ ∼0.1 (Γ: Plasma coupling constant) for non-linear interaction experiments between ion beams and plasmas. To evaluate the shock velocity, we photographed the trajectory of the shock front along the tube by a streak camera. From these measurements, we found that the shock waves are strong enough to produce a non-ideal plasma in the tube. To reduce the plasma thickness for the stopping power measurements, the effective diameter of the tube was reduced by using a tapered section. The effects of the tapered section on the shock velocity and the shape of the shock front were examined. Using a 30 tapered section, the shock velocity was increased up to 54km/s compared with 47km/s for a straight tube. [Copyright &y& Elsevier]

Abstract: High-temperature superconducting bulks with highly oriented crystallographic structures are expected to be applied for high field quasi-permanent magnets, current leads and so on. However, the bulks sometimes fracture due to the thermal stress on the cooling process or the electromagnetic force during the magnetization. Thus, it has been recognized that improvement and understanding of the mechanical properties of bulks are indispensable for practical application. In this review, we summarize the present status of evaluation process of the mechanical properties for various bulks. The Young’s modulus, Poisson’s ratio, fracture strength, fracture toughness and hardness are evaluated by tensile, bending, compression and hardness tests. The mechanical properties are anisotropic, mainly due to the crystallographic structure and pre-existing micro-cracks associated with it. Data obtained are summarized and the influential parameters associated with the microstructure and testing condition for the mechanical properties are explained. [Copyright &y& Elsevier]

Abstract: We tested an experimental setup for measurement of non-linear stopping of low-energy heavy ions in non-ideal plasmas. In this setup, we used a silicon surface-barrier charged-particle detector (SSBD), which could measure the energy of single ions. For synchronization between the plasma production and the injection of single projectiles, a fast beam kicker was installed in front of the plasma target. In order to test this setup, we used a laser-produced polyethylene plasma target instead of a shock-driven plasma device, which is under R&D process. Results of a preliminary energy loss measurement for low-speed heavy ions in the laser plasma are reported. Performance on the time resolution evaluated by using a carbon-foil target is also presented. [Copyright &y& Elsevier]

c-Myc N-terminal conserved domains, MbI and MbII, are essential for c-Myc-mediated transformation and transactivation. These domains recruit the STAGA (SPT3-TAF9-GCN5-acetyltransferase) coactivator complex, but not TFTC (TATA-binding protein-free TAF-containing) to the target gene promoter. Although components of this complex are well conserved between yeast and mammals, four mammalian orthologs of yeast SPT8, SPT20, SGF11 and SGF29 remain to be identified. Here, we isolated a rat ortholog of yeast SGF29, a component of yeast SAGA (SPT-ADA-GCN5-acetyltransferase) complex. Both rat (r) SGF29 and c-myc mRNAs were overexpressed in five out of the eight tested rodent tumor cells. rSGF29 directly interacted with rADA3 and co-immunoprecipitated with two other TFTC/STAGA components, rGCN5 and rSPT3. rSGF29 was recruited to the c-Myc target gene promoters together with c-Myc, and it activated c-Myc target gene expressions. Downregulation of rSGF29 suppressed the expression of c-Myc target genes and inhibited anchorage-independent growth and tumorigenicity and lung metastasis of rat hepatoma K2 cells when injected into nude mice. These results show that rSGF29 is a novel component of TFTC/STAGA complexes and could be involved in the c-Myc-mediated malignant transformation.Oncogene (2007) 26, 5626–5634; doi:10.1038/sj.onc.1210349; published online 5 March 2007 [ABSTRACT FROM AUTHOR]

Abstract: We developed an experimental apparatus for the study of non-linear stopping of low-energy heavy ions in non-ideal plasmas. The target plasma was produced by an electromagnetically driven shock tube. A pair of 50--diameter beam apertures was attached to the shock tube wall. These apertures confined hydrogen gas of in the tube and sustained the pressure difference (–) between the tube and the beam line. In order to measure the energy loss in the plasma in the tube, we used a semiconductor charged-particle detector, which could directly measure the kinetic energy of single particles, since the beam transmission through these apertures was very small. To synchronize the plasma production in the shock tube and the injection of projectiles, a fast beam kicker was installed in front of the plasma target. Results of preliminary experiments using thin carbon foil targets showed that the measured energy loss of single projectiles after passing through the target was in agreement with other data. The time resolution of the energy-loss measurement system was , which is enough to measure the projectile energy loss during the life time of the target plasma. [Copyright &y& Elsevier]

Abstract: A shock-driven plasma target was developed to examine non-linear interactions between low-energy heavy ions and cold-dense plasmas. MD calculations predicted that beam–plasma coupling constant must be achieved to observe the non-linearity, which corresponds to the plasma coupling constant for projectiles of and . One-dimensional numerical estimations using SESAME equation of state showed that a shock wave propagating in 5-Torr gas with 47km/s must be produced to satisfy . Utilizing an electromagnetic shock tube with a peak current of 50kA and a current rise time of 800ns, we achieved a shock speed of 45km/s. The electron density distribution of the shock-produced plasma along the beam axis was measured by a Mach–Zehnder interferometer. From this measurement we confirmed that the electron density was over and the homogeneity was acceptable during several hundred nanoseconds. The electron temperature was also determined by optical spectroscopic measurements. The Coulomb coupling constant was evaluated using these experimental data to investigate feasibility of the beam–plasma interaction experiments. [Copyright &y& Elsevier]

Abstract: In order to evaluate the mechanical properties, such as Young’s modulus and strength, of Dy123 bulk superconductors and those with 10wt.% Ag2O, we performed 3-point bending tests at room (RT) and liquid nitrogen temperatures (LNT) using specimens cut from the bulks. The Young’s modulus and the bending strength increased with decrease in temperature. In the tests loading in the direction of c-axis and ones perpendicular to it, Young’s moduli were almost comparable at both RT and LNT. Although the strengths for both orientations were also comparable at LNT, those at RT were different. Young’s moduli loaded in the direction of c-axis for Ag2O added bulk specimens, 127GPa in average at RT, were almost comparable to those without Ag2O, and 134GPa at LNT, were slightly lower than those without Ag2O. On the other hand, the strengths at both RT and LNT were enhanced by 20% by the Ag addition. The mechanical properties of Dy123 bulks without Ag2O were compared with those of Y123 bulks obtained previously. The Young’s modulus for loading in the direction of c-axis was slightly lower, and the strength was comparable to those in Y123 bulks, respectively. [Copyright &y& Elsevier]

Abstract: In order to investigate the evaluation method of the Young’s modulus of RE123 single-grain bulk superconductors, 3-point bending tests have been carried out at room and liquid nitrogen temperatures. An attempt to evaluate it from the measurements of deflection of the specimen with 3mm thickness was made. The consistent stiffness of the test machine including the jig was obtained by using a dummy specimen. For the test of the bulk, increasing repeated load within a level less than the fracture load was applied to stabilize the loading condition. The Young’s modulus calculated by using the deflection of the bulk specimen obtained subtracting the machine stiffness coincided with that obtained by the conventional method, where the strain gage was adhered to the specimen. The effects of specimen thickness and the oxygen annealing sequence with respect to specimen cutting were also investigated. [Copyright &y& Elsevier]

Abstract: In order to investigate the mechanical properties of a single-grain Y123 bulk with 15wt.% Ag at liquid nitrogen temperature (LNT), three-point bending tests of specimens cut from the bulk were carried out. The dimensions of the bending test specimens were 4×3×36mm3. The loading was carried out in the c-axis or perpendicular to it such that the normal stress induced by loading was perpendicular to the c-axis. Young’s modulus at LNT by loading in the c-axis and perpendicular to it were 143 and 134GPa and the bending strengths were 115 and 128MPa, respectively. These bending strength values were higher than those at room temperature (RT) for this bulk. From the comparison with the other rare earth element based bulks, the smaller the ionic radius of Y or rare earth elements, the higher Young’s modulus and the bending strength of the bulks. This implies that the strength is basically controlled by the ideal crystal strength of bulks, irrespective of the crystal orientation and, further, defect induced during fabrication process, so long as the defect size is comparable. The step-wise undulation in the crack propagation direction on the fracture surfaces by loading in the c-axis was significant as compared with that by loading in perpendicular to it. [Copyright &y& Elsevier]

Abstract: In order to supplement the VAMAS round robin test (RRT) on the bending strain dependence of critical current, I c, of Ag/Bi-2223 tapes conducted in 2001, a miniature bending RRT at 77K and room temperature, RT, participated by three laboratories has been conducted. Three devices developed by Goldacker of Karlsruhe, which allow continuous change of the bending radius of the sample and measurements of I c at 77K have been used. The onset strains for steep I c degradation, ε irr , at 77K, 0.55%, was larger than that at RT, 0.37%. This is due to an additional pre-compression in Bi-2223 filaments for the bending at 77K. The comparison of the present results bent at RT with those in the VAMAS-RRT showed that the scatters in the degradation behaviors were substantially small in the present results. ε irr of the former was larger than that of the latter. These appear to be explained by the different thermal histories. Based on the results, some attempts to reduce the scatter of bending test results were tried. [Copyright &y& Elsevier]

Abstract: The fracture toughness of Y123 and Gd123(Ag) single-grain bulk samples with 25 mol% RE 211 phase (and 10 wt.% Ag for the latter) prepared by the modified quench and melt-growth technique, was evaluated by the 3-point bending test at liquid nitrogen temperature (LNT) and room temperature (RT). The sharp V-notch was introduced into the specimens such that both of the loading and the crack extension directions are in the c-axis. The data for Y123 scattered from 1.2 to 2.0 MPam1/2 at LNT and 1.4 to 1.7 MPam1/2 at RT. The average value at LNT, 1.6 MPam1/2, was slightly higher than that for RT, 1.5 MPam1/2. For Gd123(Ag) the average fracture toughness at LNT, 1.8 MPam1/2 was higher than that at RT. The temperature dependence of fracture toughness for two kinds of bulks was consistent with that of the bending strength. Further, the order of the magnitude of the fracture toughness almost corresponded with that of bending strength for both bulks. [Copyright &y& Elsevier]

Abstract: In order to investigate the compressive mechanical properties of a single-grain Sm123 bulk superconductor at cryogenic temperature, compressive tests at liquid nitrogen temperature on small specimens with the dimensions of 3×3×8mm3 cut from the bulk with 45mm in diameter and 15mm in thickness were carried out. Due to the closure of pre-existing micro-cracks perpendicular to the c-axis, the average Young’s modulus in the c-axis, 93GPa, was lower than that in the direction perpendicular to the c-axis, 150GPa. While the former was higher than the value at room temperature (RT), 75GPa, the latter was slightly lower than that, 165GPa. The compressive strength in the c-axis, 466MPa, was higher than that in the direction perpendicular to the c-axis, 368MPa. This anisotropy is also ascribed to the pre-existing micro-cracks associated with the fracture mode. Both the former and the latter were higher than the values at RT, 350 and 335MPa, respectively. Most of the specimens loaded in perpendicular to the c-axis fractured along the plane perpendicular to the c-axis into a few pieces. The specimen loaded in the c-axis fractured into many small fragments, although the specimen with extraordinarily low strength fractured in a similar mode as mentioned above. [Copyright &y& Elsevier]

Abstract: Bending tests have been commonly carried out to investigate the mechanical properties of melt-processed rare earth based bulk superconductors. Tensile tests by using small specimen, however, are preferable to evaluate the detailed distribution of the mechanical properties and the intrinsic elastic modulus because no stress distributions exist in the cross-section. In this study, the tensile test method at low temperature by using specimens with the dimensions of 3×3×4mm from Y123 and Gd123 bulks was examined. They were glued to Al alloy rods at 400K by using epoxy resin. Tests were carried out at liquid nitrogen temperature (LNT) by using the immersion type jig. Although the bending strength in the direction perpendicular to the c-axis of the bulks at LNT is higher than that at room temperature (RT), the tensile strength at LNT was lower than that at RT. Many of specimens fractured near the interface between the specimen and the Al alloy rod at LNT. According to the finite element method analysis, it was shown that there was a peak thermal stress in the loading direction near the interface and it was significantly higher at LNT than that at RT. It was also shown that the replacement of the Al alloy rod to Ti rod of which the coefficient of thermal expansion is close to that of bulks significantly increased the tensile strength. [Copyright &y& Elsevier]

The spreading of water drops impinging on structured rough surfaces is studied experimentally. The rough surfaces are specially prepared with a regular pattern of surface asperities. The arrangement of the square-shaped surface asperities creates channel-like grooves on the surface. A video microscope along with a controlled light exposure system is used to construct the image sequences of the spreading process. The images are digitally analyzed to measure the temporal variation of the spreading drop diameter 2R. Results are obtained for three rough surfaces with varying asperity heights in the range of 100–500 μm and for different impact drop conditions with Weber number We in the range of 35–225. The results on the temporal variation of 2R show that, on the structured rough surfaces, the spreading occurs simultaneously both inside and above the texture pattern of the surfaces. For a given surface geometry, the volume of liquid flowing inside the grooves of the surface increases with increasing We. Consequently, the values of 2R measured inside the texture pattern are larger than those measured above the texture pattern, and their difference increases with increasing We. The arrangement of the surface asperities influences the spreading pattern of an impacting drop spreading axisymmetrically. For the texture geometry used in the present study, the spreading pattern resembles a regular rhombus shape for the impact of low We drops and becomes complex at high We. The spreading distances, measured both inside and above the texture pattern of the structured rough surfaces, are nearer to the measurements recorded on the smooth surface if the asperity height of the rough surface is smaller than the thickness of the spreading liquid lamella; however, the surface asperities influence the spreading pattern drastically and create a liquid splash. [ABSTRACT FROM AUTHOR]

The monotonic and the repeated bending tests on the Y123 single grain bulk superconductor sample were carried out. The average Young''s modulus at liquid nitrogen temperature (LNT), 148 GPa, was higher than that at room temperature (RT), 132 GPa. The average bending strength at LNT, 90 MPa, was also higher than that at RT, 74 MPa. The Weibull coefficient for the bending strength at RT, 17.6, was significantly larger than that at LNT, 6.1. The specimen cut from the bottom region of the bulk superconductor showed slightly higher value of the Young''s modulus and lower value of the bending strength. The fatigue endurance limit for the repeated pulsating loading up to 5 × 104 cycles at LNT, 70 MPa, was about 80% of the bending strength. [Copyright &y& Elsevier]

Tensile and 3-point bending tests of specimens cut from an Y123 and a Gd123 bulk superconductors fabricated by using the modified QMG (Quench and Melt Growth) process were carried out at room temperature. The mechanical properties obtained by two testing method were compared. The average values of the Young''s modulus obtained by tensile tests, 122 GPa for Y123 and 109 GPa for Gd123, were lower than those obtained by bending tests, 132 and 117 GPa, respectively. The average values of the tensile strength, 39 MPa for Y123 and 42 MPa for Gd123, were also lower than those of the bending strength, 74 MPa and 71 MPa, respectively. There was no appreciable difference between the Weibull coefficient for the tensile strength and that for the bending strength, 6.9, in Gd123. On the other hand, the coefficient for the bending strength, 17.6, was significantly higher than that for the tensile strength, 6.8, in Y123. [Copyright &y& Elsevier]

Bending strain dependence of critical current, Ic, of Ag/Bi-2223 57 filament tapes was investigated at 77 K and room temperature, RT, using a device invented by Goldacker. The strain where Ic start to degrade steeply at 77 K, 0.48%, was larger than that at RT, 0.36%. This is an indication of an additional pre-compression in filaments to be bent at 77 K compared with that at RT. According to the voltage measurements using multiple taps in the longitudinal direction, the Ic degradation behaviors at both temperatures varied depending on the section in the tape, due presumably to the difference in the crack propagation characteristics associated with the non-uniformity of the micro-structure. The onset strain for Ic degradation was more precisely determined. The degradation characteristics were shifted to the smaller strain in the present result as compared with that obtained by bending tests using G10 sample holders of different bending radius. The difference can be explained by the different thermal history on setting specimens to the holder and the constraints during cooling. The repeated bending tests at 77 K showed that the discrimination between the gradual and steep degradation stages was clear and the degradation was controlled by both the maximum strain and the strain range. [Copyright &y& Elsevier]

In order to investigate the compressive mechanical characteristics of Sm 123 single-grain bulk superconductors fabricated by TSMG method, compressive tests in the direction parallel and perpendicular to the c-axis have been carried out by using small specimens cut from the bulk samples. Stress-strain curves in the direction perpendicular to the c-axis were almost linear. The Young's moduli measured were 155-165 GPa. In the case of loading parallel to the c-axis, the curves were exponential in the low stress region. As the stress increased, they tended to a linear relation. The apparent Young's modulus in this region was 75-110 GPa. These characteristics are mainly ascribed to the closure behavior of pre-existing micro-cracks perpendicular to the c-axis. The average fracture strength in the direction of c-axis, 350-400 MPa, was larger than that perpendicular to it, 235-275 MPa. Specimens in the former were generally broken into great many small pieces while those in the latter were broken into some parts by lateral cracking. The compressive Young's modulus and the fracture strength for each direction were higher than those evaluated by the tensile loading, respectively. The effects of specimen length on the compressive mechanical properties were also discussed. [ABSTRACT FROM AUTHOR]

In order to investigate the mechanical properties of Sm–Ba–Cu–O bulk superconductors fabricated using TSMG method such that Sm123:Sm211 in molar ratio was 100−Z:Z (Z=16.7, 28.6), tensile tests in the direction perpendicular to the c-axis have been carried out at room temperature by using the small specimens cut from the bulk samples. Although, non-linear behavior was seen in a few specimens, stress–strain curves were almost linear until the fracture. The non-linear behavior is presumably ascribed to the opening of pre-existing micro-cracks parallel to the c-axis and the slow propagation of them. The Young’s modulus for both samples was almost equal. Poisson’s ratio based on the transverse strain parallel to the c-axis was smaller than that based on the strain perpendicular to it. One of the possible reasons for it will be the reduced transverse shrinkage by the constraint at the interface between the specimen and the aluminum alloy tensile rod coupled with the opening of the pre-existing micro-cracks perpendicular to the c-axis. Tensile strength for the sample with 28.6 mol% of Sm211 was not higher than that with 16.7 mol%. It is presumably ascribed to the low cohesive force between the Sm211 particles and the matrix. The effect of loading condition with respect to that of the crystal growth on the strength was not clear. No significant difference in the strength was found between the specimens including a growth sector boundary and those without it. [Copyright &y& Elsevier]

In order to investigate the effects of Ag content on the mechanical properties of a high performance melt-processed (Nd,Eu,Gd)Ba2Cu3Oy single grain bulk superconductors with 30 mol% Gd2BaCuO5, tensile tests of specimens cut from the bulks have been carried out at room temperature. The tensile strength in the direction perpendicular to the c-axis of the sample with 20 wt.% Ag was higher than that of the sample with 10 wt.% Ag. This is ascribed to a decrease in the void fraction and suppression of cracks by an increased Ag particles revealed by the microstructure image analysis. The almost identical value of Young’s modulus obtained for both of the samples are presumably due to the balance of the effects of the voids and soft Ag particles mentioned above. Comparing these results with that in the c-axis direction and that obtained by the compressive test, the anisotropy of the elastic behavior associated with the effect of pre-existing micro-cracks perpendicular to the c-axis was discussed. [Copyright &y& Elsevier]

In order to investigate the mechanical properties of Gd123 single-grain bulk superconductors fabricated using a modified quench and melt growth method, tensile tests in the direction parallel and perpendicular to the c-axis have been carried out at 293 K by using the small specimens cut from bulk superconductors. As for the mechanical properties perpendicular to the c-axis, there was no significant difference between those in the crystal growth direction and those perpendicular to it. While the average value of the Young’s modulus of the bulk sample with 33.0 mol%-Gd211 secondary phase particles, 118 GPa, was higher than that of the bulk sample with 28.7 mol%-Gd211, 111 GPa, the average value of the tensile strength of the former, 36 MPa, was lower than that of the latter, 40 MPa. The tensile strength and the Young’s modulus in the c-axis, 10 MPa and 37 GPa, were quite low compared with those mentioned above. Poisson’s ratio based on the transverse strain in the c-axis, 0.15, was significantly smaller than that perpendicular to it, 0.30. In the specimens with higher length, however, the difference was decreased to some extent. With regard to the anisotropy of the Poisson’s ratio, the effect of a pre-existing micro-crack opening in the c-axis direction was discussed coupled with the constraints at the interfaces between the specimen and the sample holder. [Copyright &y& Elsevier]

Summary The involvement of various cytokines and chemokines has been reported in the pathogenesis of bullous pemphigoid (BP). Double-filtration plasmapheresis (DFPP) is an effective treatment for BP but the mechanism of action remains unclear. Using semiquantitative reverse transcription–polymerase chain reaction, we examined levels of transcripts for various cytokines and chemokines in freshly isolated peripheral blood mononuclear cells in a patient with BP before and after DFPP treatment. DFPP was performed four times. Relative levels of transcripts for interleukin (IL)-8, macrophage inflammatory protein (MIP)-1α and IL-5, and the ratio of relative levels of transcripts for IL-4 and interferon (IFN)-γ, were higher, before treatment, than in healthy controls, and decreased when the extent of the lesions was reduced. Relative levels of transcripts for tumour necrosis factor (TNF)-α and IL-4 also decreased with regression of lesions, although they were similar to or lower than the corresponding levels in healthy individuals. When eruptions recurred, relative levels of transcripts for IL-8, MIP-1α, RANTES (regulated upon activation normal T cell expressed and secreted), IL-2, IFN-γ and TNF-α were very much higher than those prior to the recurrence, while relative levels of mRNAs for IL-4 and IL-5 did not increase. Relative levels of transcripts for IL-8, MIP-1α, TNF-α and IL-2 were lower at the end of each individual DFPP and after the four treatments than at the beginning of treatment. Our observations suggest that cytokines and chemokines produced in mononuclear cells play important roles in the pathogenesis of BP and that regulation of their expression might be involved in the therapeutic effects of DFPP in BP. [ABSTRACT FROM AUTHOR]

In order to investigate the mechanical properties of a recently developed high performance melt-processed (Nd,Eu,Gd)Ba2Cu3Oy (NEG-123) single grain bulk superconductor, tensile tests of specimens cut from the bulk have been carried out at room temperature, 293 K, and at liquid nitrogen temperature, 77 K. Tensile stress was applied in a- or b-direction. The maximum value of tensile strength and Young''s modulus at 77 K, 41 MPa and 158 GPa were higher than those at 293 K, 33 MPa and 134 GPa in the NEG-123 sample with 40 mol% (Nd,Eu,Gd)2BaCuO5 (NEG-211) secondary phase particles, 0.5 wt% Pt and 10 wt% Ag2O. Tensile strength of the sample added 30 mol% NEG-211 and the sample added 30 mol% Gd2BaCuOy instead of 40 mol% NEG-211 that was added to the sample described above have also been investigated. [Copyright &y& Elsevier]

The tensile strength in a- or b-direction of melt-processed (Sm,Gd)–Ba–Cu–O single grain bulk superconductor without Ag addition have been investigated by using specimens cut from the bulk sample. The maximum value of tensile strength of the specimens annealed in pure O2 atmosphere was higher than that of the Y– and Sm–Ba–Cu–O bulk superconductor without Ag addition previously reported. The tensile strength was relatively higher in the central region of the bulk. Fracture surface of the specimens with relatively high tensile strength included the large region with the steps perpendicular to the c-direction. Flow markings showing crack propagation were found on the region without steps on the fracture surfaces. [Copyright &y& Elsevier]

In order to investigate the mechanical properties of a recently developed high performance melt-processed (Nd,Eu,Gd)Ba2Cu3Oy (NEG-123) single grain bulk superconductor, tensile tests of specimens cut from the bulk have been carried out at room temperature, 293 K, and at liquid nitrogen temperature, 77 K. Tensile stress was applied in a- or b-direction. The maximum value of tensile strength and Young''s modulus at 77 K, 41 MPa and 158 GPa were higher than those at 293 K, 33 MPa and 134 GPa in the NEG-123 sample with 40 mol% (Nd,Eu,Gd)2BaCuO5 (NEG-211) secondary phase particles, 0.5 wt% Pt and 10 wt% Ag2O. Tensile strength of the sample added 30 mol% NEG-211 and the sample added 30 mol% Gd2BaCuOy instead of 40 mol% NEG-211 that was added to the sample described above have also been investigated. [ABSTRACT FROM AUTHOR]

The tensile strength in a- or b-direction of melt-processed (Sm,Gd)–Ba–Cu–O single grain bulk superconductor without Ag addition have been investigated by using specimens cut from the bulk sample. The maximum value of tensile strength of the specimens annealed in pure O2 atmosphere was higher than that of the Y– and Sm–Ba–Cu–O bulk superconductor without Ag addition previously reported. The tensile strength was relatively higher in the central region of the bulk. Fracture surface of the specimens with relatively high tensile strength included the large region with the steps perpendicular to the c-direction. Flow markings showing crack propagation were found on the region without steps on the fracture surfaces. [ABSTRACT FROM AUTHOR]

The effects of bluing and shot peening on the S-N curve of eutectoid steel wires, drawn up to a strain of 3.5, were studied. Vickers hardness tests and measurements of residual stresses in the direction of the wire axis using Heyn's method were also performed. The fatigue limit of the wires, together with the hardness and the residual stresses in the surface layer of the wires, increased with the drawing strain. The bluing increased the hardness at low temperatures up to 300 °C and then decreased at higher temperatures. The residual stress decreased monotonically to zero with the temperature rise up to 500 °C. Bluing increased the fatigue limit, being highest at 400 °C, through competitive effects of strain ageing and recovery of the structure. Shot peening slightly increased the surface hardness and drastically changed the residual stress from 1000 MPa to - 300 MPa, which resulted in the highest fatigue limit of 1200 MPa in the wire drawn to a strain of 3.55. It is concluded that both the hardness and the residual stress are the controlling factors for the fatigue limit of the wires examined, where the crack initiation is observed to occur from the surface flaw. [ABSTRACT FROM AUTHOR]

Previous studies using in vitro systems with various stimuli have shown that PBMC from patients with AD show increased levels of IL-4 but decreased levels of interferon-gamma (IFN-γ) compared with PBMC from normal controls. However, in vitro conditions do not always mimic the in vivo condition. We therefore believe that it is important to quantify the expression of these cytokines in freshly isolated PBMC. This study examines the expression of IFN-γ, IL-4 and IL-13 mRNA in freshly isolated PBMC from adult patients with AD, from patients with psoriasis vulgaris and from healthy adults, using the semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method. Levels of IFN-γ mRNA were significantly lower in PBMC of patients with AD than in controls. IL-4 mRNA levels did not differ significantly between groups. Conversely, levels of mRNA for IL-13 were significantly greater in PBMC of patients with AD than in controls. An increase in IL-13 expression may regulate the in vivo synthesis of IgE in patients with AD. [ABSTRACT FROM AUTHOR]

The Kei-source is a compact electron cyclotron resonance ion source using only permanent magnets and a frequency of 10 GHz. It was developed at the National Institute of Radiological Sciences (NIRS) for producing C4+ ions oriented for high-energy carbon therapy. It has also been used as an ion source for the NIRS-930 cyclotron. Its microwave band region for the traveling-wave-tube amplifier and maximum output power are 8-10 GHz and 350 W, respectively. Since 2006, it has provided various ion beams such as proton, deuteron, carbon, oxygen, and neon with sufficient intensity (200 µAf o r proton and deuteron, 50 µAf o rC4+, for example) and good stability for radioisotope production, tests of radiation damage, and basic research experiments. Its horizontal and vertical emittances were measured using a screen monitor and waist-scan. The present paper reports the current status of the Kei-source. [ABSTRACT FROM AUTHOR]

In situ femtosecond x-ray diffraction measurements and ab initio molecular dynamics simulations were performed to study the liquid structure of tantalum shock released from several hundred gigapascals (GPa) on the nanosecond timescale. The results show that the internal negative pressure applied to the liquid tantalum reached -5.6 (0.8)GPa, suggesting the existence of a liquid-gas mixing state due to cavitation. This is the first direct evidence to prove the classical nucleation theory which predicts that liquids with high surface tension can support GPa regime tensile stress. [ABSTRACT FROM AUTHOR]

Purpose: We evaluated the safety of a gadolinium (Gd) contrast agent in hemodialysis patients.Material and Methods: Seventy hemodialysis patients underwent contrast-enhanced MR examination. After the examination, the patients were hemodialyzed on a usual schedule, i.e., 3 times per week at 4 h each session. The hemodialysis was performed on the same day in 16 patients, the next day in 34, 2 days later in 14 and 3 days later in 6 patients. Serum Gd concentrations before and after the first to fourth hemodialysis sessions were analyzed in 11 patients. Cardiovascular, cutaneous, respiratory, psycho-neurological and digestive side effects were evaluated in all patients. Changes in liver and kidney functions, blood counts, and electrolytes were also checked.Results and Conclusion: Neither side effects nor blood changes were noted in any of the patients. Average excretory rates were 78.2%, 95.6%, 98.7% and 99.5% in the first to fourth hemodialysis sessions, respectively. These results suggest that Gd contrast agents can be used in hemodialysis patients if hemodialysis is carried out promptly after the examination. [ABSTRACT FROM AUTHOR]

Magnetocaloric and related properties of Ru and Ni substituted (MnFe)2(PSi) are presented. It is found that Ru and Ni are effective doping elements to reduce the thermal hysteresis of (MnFe)2(PSi). The origin of the thermal hysteresis is discussed on the basis of a thermodynamic model. It is shown that the elastic energy is responsible for the thermal hysteresis. We also show recent developments of the production process of Mn compounds in an industrial scale. [ABSTRACT FROM AUTHOR]

Investigates the influence of fast neutron irradiation on critical current and its strain dependence in a bronze processed fine multifilamentary Nb[sub3]Sn superconducting composite. List of the specification of the bronze processed fine multifilamentary Nb[sub3]Sn superconducting composite wire specimen; Summary of material parameters of the multifilamentary Nb[sub3]Sn.

To increase the beam intensity of cyclotrons used for producing radionuclides, beam loss during extraction must be reduced. Extraction efficiency is limited by the beam parameters in front of the deflector, especially angular distribution. Computer simulation of the second harmonic mode for 18 MeV protons, which is frequently used, has been carried out to understand beam behavior in a cyclotron. The extraction efficiency is determined by the width of the angular distribution of particles in the phase space plot at the deflector. An effective method to reduce the width is to shorten the bunch at injection. The simulation shows that the bunch phase length at injection must be ⩽30° to realize a 30 μA extraction beam current and satisfy the deflector heat limit of 200 W. [ABSTRACT FROM AUTHOR]

Laser--plasma interaction and hot electrons have been characterized in detail in laser irradiation conditions relevant for direct-drive inertial confinement fusion. The experiment was carried out at the Gekko XII laser facility in multibeam planar target geometry at an intensity of approximately 3x1015 W/cm². Experimental data suggest that high-energy electrons, with temperatures of 20-50 keV and conversion efficiencies ofη<1%, were mainly produced by the damping of electron plasma waves driven by two-plasmon decay (TPD). Stimulated Raman scattering (SRS) is observed in a near-threshold growth regime, producing a reflectivity of approximately 0.01%, and is well described by an analytical model accounting for the convective growth in independent speckles. The experiment reveals that both TPD and SRS are collectively driven by multiple beams, resulting in a more vigorous growth than that driven by single-beam laser intensity. [ABSTRACT FROM AUTHOR]

Abstract: An inter-comparison program (round-robin-test) aimed at the establishment of a standard test method for the bending strain effect on the critical current in Ag alloy-sheathed Bi-2223 tapes was implemented with participation of 12 laboratories around the world. Samples were bent at room temperature using bending devices that were specially designed for this RRT. The critical current was measured at 77K and in the self-field. After critical current measurement of an unbent sample, bending of the sample and subsequent critical current measurements were done from 0.2% to 1.0% in 0.2% steps of strains on a single sample. Reported data from participants showed that the critical current values start to decrease from 0.4% strain and continue to decrease to 1.0% strain. Moreover, the data scatter starts to increase stepwise at 0.4% strain, being correspondent to the variation in the critical current values with bending strain, and it continues to increase gradually to 1.0% strain. The coefficient of variation values are 2.5%, 5.1% and 6.4% for 0%, 0.4% and 1.0% bending strain, respectively. Results were also compared in terms of the irreversible bending strain. Possible sources of error are discussed. [Copyright &y& Elsevier]