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Metal-ion implantation is well established as a suitable technique for fabrication of nanoparticles embedded in insulators. Photon emission induced by 60 keV Cu − incident ion was in situ measured over a wavelength range from 200 to 900 nm. Special attention was paid to the behavior of the Cu I atomic line emission related to the mass transport of implants. Based on comparison of experimental results for the wide band gap materials (SiO 2 and MgAl 2 O 4 ) with those for metals (W, Mo, Al), it is concluded that, at the beginning of ion bombardment, the radiation is mostly emitted by backscattered atoms. The causes of this are different for the different groups of materials: the high backscattering yield in the case of metals and the high survival probability of the excited backscattered atoms in the case of insulators, when the excitation levels lie below the conduction band edge and the radiative decay is only the available channel for deexcitation. Significant contribution in the Cu I line intensity was observed with increasing dose due to sputtered Cu atoms.

Ion-induced surface modification processes of polystyrene (PS) and high-density polyethylene (HDPE) have been studied by either in situ photon-emission spectroscopy or ex situ surface analyses. Heavy Cuions of 60 keV irradiated the polymers at a dose rate of 1 lA/cm 2 and ion-induced photon emission was in situ measured in a spectral region of 250-850 nm. Ion-induced chemical reactions of the surface layers were ex situ evaluated by X-ray photoelectron spectroscopy (XPS). Intensity, spectral shape and dose dependence of the photon emission were significantly different between aromatic-containing polymers (PS) and linear polymers (HDPE) in the same irradiation condition. The emission spectrum of HDPE represented a broad band with a maximum at about 595 nm, while that of PS showed a sharp peak around 656 nm. The total emission yield observed for PS was much lower than that of HDPE, and the decay rates of emission intensity for PS were different from that of HDPE in a dose region less than 10 14 ions/cm 2 . The XPS analyses showed chemical change of the surface bonding. These results suggested that ion-induced processes caused hydrogen extraction, crosslinking and bond scission of the matrix. 2002 Elsevier Science B.V. All rights reserved.

Ion-induced photon emission under heavy-ion bombardment has been studied over an energy range from near-infrared to vacuum-ultraviolet. Time-resolved optical devices with fast-response CCD cameras detected photons from a-SiO2 under implantation with negative Cu ions of 60 keV, up to a dose rate of 100 μA/cm2. The ion-induced photon spectra consisted of sharp line spectra due to isolated atoms of Si, Cu and a broad band of visible light. The line spectra resulted from an ion-induced glow above the surface and indicated pronounced outward transport of Cu atoms to the vacuum. Intensity of the line spectra and the broad band varied non-linearly with dose and dose rate. The in-situ spectroscopy provided diagnostic information of surface- and intra-solid processes associated with nanoparticle formation at high dose rates. The Cu sublimation reflected from presence of a Cu-depleted zone beneath the surface, which is one of the important factors to form a two-dimensional arrangement of nanoparticles.

Photon irradiation effects during heavy-ion implantation have been studied to distinguish and control electronic excitation effects on surface modification of insulators, particularly on nanoparticle formation in insulators. Photons of a sub-gap energy (2.3 eV) and high-energy Cu ions were applied to substrates of a-SiO 2 (KU-1). The Cu 2+ ions of 3 MeV irradiated the specimens at 10 μA/cm 2 to 3×10 17 ions/cm 2 , and the 532 nm-YAG laser, either simultaneously or sequentially, irradiated them at 0.2 J/cm 2 · pulse , 10 Hz, for a period corresponding to the ion dose. Atomic-force microscopy and cross-sectional transmission electron microscopy were conducted to study the surface- and bulk morphology, respectively. The ion-alone irradiation smoothed the surface, up to the high dose. Intense photon irradiation under ion implantation significantly roughened the surface and concurrently promoted nanoparticle formation. Optical absorption spectra showed that simultaneous irradiation decreased radiation-induced defects for the low dose and enhanced surface plasmon of nanoparticles for the high dose. The results indicate that intense photon irradiation, coexistent with heavy-ion irradiation, excites transient electronic states and/or implanted atoms and result in surface desorption, defect annihilation and nanoparticle formation. The in-beam photon irradiation is suitable for optical material processing, both for the matrix and nanoparticles.

Ion-induced photon emission under 60 keV Cu − implantation into the insulators of MgAl 2 O 4 and LiNbO 3 was in situ measured over a wide wavelength range from 200 to 900 nm. The formation of the Mg and Li deficient layers for the respective insulator was detected based on the dose dependence of the Al, Mg and Li atomic line intensities. The Al I and Mg I line intensities from spinel exhibit different behaviors depending on irradiation temperatures: they gradually decrease while the (Al I)/(Mg I) ratio increases up to dose of 3×10 17 ions/cm 2 at room temperature or exhibits a steady-state tendency at high temperature. Sharp decrease of Li I line intensity from LiNbO 3 under high dose rate bombardment indicates drastic changes of surface layer that may alter the phase stability and optical performance of insulators.

Objective The objective of this paper is to identify predictors for the response to treatment of acute lupus hemophagocytic syndrome (ALHS). Methods We reviewed seven cases with ALHS admitted to our hospital and published ALHS cases identified in the 2001–2014 Medline database, and then conducted univariate and multivariate analyses to identify predictors for the response to treatment. Results Review of our cases showed a significant and negative correlation between serum ferritin and anti-DNA antibody ( p = 0.0025). All three patients treated with cyclosporine A (CsA) were considered responders despite high serum ferritin and corticosteroid resistance. We also reviewed 93 patients with ALHS identified in 46 articles. Multiple logistic regression analysis identified C-reactive protein (CRP) (OR 0.83, p = 0.042) and hemoglobin (OR 1.53, p = 0.026) measured at diagnosis of ALHS as significant predictors of the response to corticosteroid monotherapy. Moreover, among 32 patients treated with CsA, serum ferritin was significantly higher in CsA responders (12163 ± 16864 µg/l, n = 22) than in non-responders (3456 ± 6267/µg/l, p = 0.020, n = 10). Leukocyte count was significantly lower in the CsA responders (1940.0 ± 972.3/µl) than in the non-responders (3253 ± 2198/µl, p = 0.034). Conclusion Low CRP and high hemoglobin can predict a positive response to corticosteroid monotherapy while high serum ferritin and low leukocyte count can predict a positive response to CsA in patients with ALHS and therefore, when corticosteroid monotherapy is not effective in such cases, CsA could be the first choice of an additional immunosuppressive agent.

The 500 keV negative-ion based neutral beam injector for JT-60U has been operated since 1996 and has injected so far a neutral beam power of 5.2 MW at 350 keV for 0.7 s. In order to further increase the beam power and extend the beam pulse duration time, a few issues concerning the negative ion source have to be solved. The most serious issue of them is non-uniformity of source plasma in the arc chamber. Two out of some countermeasures for improving the non-uniformity have been tried. The first is changing the spatial distribution of the arc discharge through regulating arc current resistors which connect in series to each of eight filament groups. The second is masking both ends of the plasma grid with thin molybdenum plates to block beam extraction at the edges. Owing to these countermeasures, the acceleration efficiency of the deuterium negative ion beams in the accelerator has improved by more than 30% from 0.55 to 0.74.

Surface morphology and structural changes of amorphous (a-), crystalline (c-) SiO2 and MgAl2O4 spinel, implanted with high-current Cu− of 60 keV, were studied using atomic force microscopy. Kinetic variation of the surface morphology was evaluated by changing dose rate from 1 to 100 μA/cm2. In the cases of a-SiO2 and c-SiO2, the surface morphology significantly varied with dose rate: dome-type textures in the lower dose-rate region caused radiation-induced roughening, while net-type ones in the higher region occurred with radiation-induced smoothing. Step-height measurements showed radiation-induced expansion and compaction for c-SiO2 and a-SiO2, respectively. Radiation-induced amorphization is responsible for the expansion processes of c-SiO2. Contrarily, no amorphization was observed in the spinel up to dose rates of about 100 μA/cm2, although radiation-induced swelling, due to defect accumulation, was discernible by the step-height measurement. The surface morphology and the roughness of the spinel wer...

The several hundred keV neutral beamline which is now operating on JT-60U marks the first usage of negative ion sources to produce high power neutral beams. Because this was such a large advance in the state of the art with respect to all system parameters, many new physical processes appeared during the earlier phases of the beam injection experiments. The physical mechanisms responsible for these processes have been explored, and solutions have been implemented for some of them, in particular excessive beam stripping, the secular dependence of the arc and beam parameters, and the non-uniformity of the plasma illuminating the beam extraction grid. This has reduced the percentage of beam heat loading on the downstream grids by roughly a third and has permitted longer beam pulses at higher powers. Progress is being made in improving the negative ion current density and in coping with the sensitivity of the caesium in the ion sources to oxidation by tiny air or water leaks, and the cathode operation is being altered.

Steady-state optical absorption and nonlinear transient resonance have been studied for Cu nanoparticle composites, fabricated in magnesium aluminate spinel by high-current negative ion implantation. The implantation was conducted at high ion fluxes of 60 keV up to a total dose of 3×1016 ions/cm2. Optical absorption strongly depended on dose rate, ranging from 1 to 100 μA/cm2. The dose rate dependence of the absorption spectra around the surface plasmon resonance behaved analogously to that of a-SiO2, though the radiation-induced absorption band depended on stoichiometry of the spinel. The spectral shape of transient absorption at various dose rates is similar but the bleached plasmon band shifts is in parallel with the steady-state surface plasmon resonance. The dose rate chiefly influences dielectric properties of a spinel matrix but not that of particles.

Silicon-thermal-oxide (a-SiO2) films of 115 nm thick on Si wafers are implanted by high-flux Cu negative-ions of 60 keV. Optical reflectivity measurements show that the Si substrates are transformed into an amorphous-like state after the implantation. The “amorphization” is ascribed to recoil atoms, not directly to the incident Cu ions. The crystallinity is recovered after a heat treatment at 900°C for 1 h in Ar gas. The interference fringes in the reflectivity spectra shift to high energy side at 60 μA / cm 2 and the higher fluxes, indicating decrease of the oxide thickness. At the same fluxes, AFM observation shows a prominent change of surface morphology and a large increase of step-height at implanted–unimplanted area boundaries, indicating enhanced sputtering under high-flux implantation.

Co-irradiation effects of ions and photons on insulators have been studied to explore electronic excitation effects on surface modification. Ion implantation of MeV–Cu ions and green-laser irradiation was conducted to a-SiO2 (820 ppm OH − ) and spinel MgO·2.4(Al2O3). The dose rate varied from 2 to 10 μA/cm 2 for Cu ions of 3 MeV and from 0.05 to 0.2 J/cm 2 · pulse at 10 Hz for YAG–SHG laser, for a period corresponding to 3×10 16 ions/cm 2 . Atomic-force microscopy (AFM) was conducted to evaluate the surface morphology. Optical absorption was measured in a photon energy range from 0.5 to 6.5 eV. Single irradiation, either Cu ion-alone or laser-alone, caused few discernible changes of surface morphology. Co-irradiation of ions and photons at high power densities caused significant changes in the surface texture with an increase in surface roughness. Optical absorbance of the co-irradiated specimens also showed a change larger than that of sequentially irradiated ones. The results indicate that nonlinear synergistic effects are induced by the co-irradiation and may develop to a new modification method.

Development for enhancing the beam characteristics in the N-NBI system for JT-60U has been continued since 1996. In order to increase beam power and duration time, a few countermeasures for improvement of source plasma non-uniformity have been tried. The first is changing arc current limiting resistors for changing arc current distribution, the second is regulating filament temperature for altering arc discharge mode, the third is optimizing a magnetic barrier in arc chamber, and the fourth is blocking the beam acceleration at a strongly non-uniform source plasma area by masking both upper and lower edge of plasma grid. All of these countermeasures have been confirmed to be effective.

The positive-ion based NB1 system for JT-60 began operation in 1986 with hydrogen beam, and had injected the neutral beam power of 27 MW at 75 keV. The beam species has been changed to deuterium through changing the ion sources and beam-line components in 1991. The NBI has injected a deuterium beam of 40 MW at 96 keV in 1996. In 2000, the computer control system for the beam operation has been changed from a mini-computer to a workstation system in order to match a great variety of beam injection parameters, and the operation capability has greatly improved.

This article describes a suitable network architecture for the mobile communications system beyond IMT-2000. The rapid developments in mobile communication services have significantly altered the lifestyles of many people. With the increasing demand for access to the Internet, the amount of data traffic in mobile communication networks has significantly increased and will dominate these networks. Therefore, mobile networks beyond IMT-2000 should offer higher bit rate channels and adapt to multimedia traffic more efficiently. This article first forecasts market trends in mobile communications in order to identify requirements of the mobile communications system beyond IMT-2000. Then the article considers the network architecture of the mobile communications system beyond IMT-2000 that will satisfy those requirements.

In fabricating metal nanoparticles in insulators, high-current negative ions have been shown to cause efficient and spontaneous growth of nanospheres. The in-beam growth is inevitably subjected to rearrangement of implanted atoms, departing from initially deposited positions. For high-current techniques for insulators, we discuss important experimental factors and explore possible mechanisms of the in-beam growth and atomic rearrangement of nanoparticles. Experimental data of interest are for negative Cu ion implantation at 60 keV into insulators, amorphous(a-), crystalline (c-) SiO 2 and a spinel oxide, MgAl 2 O 4 . Dose rates ranged up to 260 μA/cm 2 , with a total dose of 3.0×10 16 ions/cm 2 . Nanoparticle morphology and surface morphology by AFM were significantly dependent not only on dose rate but also on the boundary conditions. With increasing dose rate, the in-beam growth of nanoparticles became pronounced and the atomic profile shifted toward the surface. Since beam heating, especially in vacuum, is of concern, thermal analysis was carried out with a one-dimensional simulation code. Candidate mechanisms are depth-oriented gradients of deposited nuclear/electronic energy, chemical/elastic potentials and thermal effects. The relevant mechanisms are explored among these candidates.

Intense Cu− ions of 60 keV spontaneously grow nanospheres embedded within a shallow depth in insulators, which exhibit optical nonlinearity. The in-beam growth of nanoparticles is preferred but subjected to phase instability. Spinel oxides may be a candidate substrate to realize the phase stability, because of good radiation resistance and sufficient transparency. Spinel of MgAl2O4 and amorphous(a-) SiO2 were irradiated with Cu− at dose rates up to 100 μA/cm2, at a total dose of 3.0 × 1016 ions/cm2. Nanocrystal morphology and optical absorption (hν=0.5 – 5 eV) varied depending on dose rate. At high dose rates, a-SiO2 showed a strong tendency of depth-dependent rearrangement and particle coarsening. The MgAl2O4 also showed spontaneous precipitation of nanoparticles but, in contrast, neither long-range rearrangement of implants nor particle coarsening, up to high dose rates. Therefore, the MgAl2O4 spinel is a promising substrate to realize fine and stable nanostructures.

Thermal stability of nanoparticles, fabricated by high-current negative ions, has been studied focusing on optical applications. Negative Cu ions of 60 keV were irradiated to silica glasses at high dose rates up to 50 μA/cm2, to a total dose of 3×10 16 ions/cm 2 . The high-current implantation caused a bimodal distribution of Cu nanoparticles. Thermal annealing at 773–1273 K for 1 h was applied to the specimens. For each step, optical absorption was measured in an energy range from 0.5 to 6.5 eV and nanoparticle morphology was evaluated by cross-sectional TEM. Depth profiles of Cu atoms were compared to those by RBS. Thermal annealing below 873 K gave no discernible changes in either nanoparticle morphology or absorption spectra. Above 1073 K, pronounced coarsening of Cu particles occurred, with enhancing the bimodal distribution. Around 1273 K, all the Cu particles disappeared, suggesting evaporation of Cu implants from the surface. The result indicates that the nanoparticle structure is thermally stable below about 873 K, and becomes unstable at higher temperatures.

Flow-through thin latissimus dorsi perforator flaps were used in six cases with complicated defects of the legs. This flap has a small amount of latissimus dorsi muscle with a considerable amount of fatty tissue removed to make a thin flap. In addition, the flap has several branches of the subscapular vessel, which are interposed to the recipient vessels of the legs. The advantages of this thin flap are: (1) flow-through vascular reconstruction can preserve the main vessels of the damaged legs; (2) the double arterial inflows and venous drainage systems of the flap ensure safe vascularization of the flap; (3) a flow-through venous drainage system from the distal extremities can also be established to prevent congestion of the affected legs; (4) this flap is versatile (it can be either thin or large); and (5) even in emergent ischemic legs, simultaneous elevation of the flap is possible with preparation of the legs. This flow-through flap is indicated for: (1) cases with a large skin defect and obstruction of the main vessels in the leg; (2) cases with a possibility of tumor recurrence in the legs; and (3) young women or girls with a large defect in the legs, rather than the rectus abdominis musculocutaneous flap.

Optical properties of negative Cu ion-implanted silica glasses were measured over a photon energy range 0.5–6.5 eV. The implantation was conducted at high beam fluxes of 60 keV energy up to a total fluence of 3.0 × 1016 ions/cm2. From the transmission and reflection data, dielectric constants, eeff for the Cu implanted layer and em for the Cu nanoparticles, were self-consistently determined. In the dielectric spectra, bands due to the Cu particles were evidently present below 4.2 eV. An absorption band of the irradiated silica screened that of the Cu particles in the higher photon region. In the imaginary em spectrum, the intraband contribution disappeared owing to the nano-size effect and the interband contribution at 3.8 eV became smaller than that of bulk Cu. Third-order susceptibility χm(3) was also evaluated with the degenerate four-wave mixing and was of the order of 10−8–10−9 esu.

Head-attached interface device (HIDE) has been developed as a new type of human interface device in an actual work environment. The HIDE has flexible integrated functions which consist of speech recognition and view direction detection as hand-free input channels, direct presentation of audio/visual information as output channels, and mobile system configuration. In this paper, the design concept of the HIDE was first introduced, and individual functions to configure the design concept were developed by their separate testing. An integrated prototype system HIDE was then produced, and its functional evaluation test was made to examine the individual functions as the whole system. It was confirmed that the HIDE would be feasible enough to introduce in practical use.

Spectra of the optical transmission of Al2O3 were measured during implantation of 60 keV Cu− ions at ion fluxes from 5 to 50 μA/cm2, to monitor formation of Cu nanoparticles. The precipitation threshold is flux-dependent. The formation of nanoparticles is (a) efficient up to a fluences of 2 × 1017 ions/cm2 and (b) most efficient for a flux of 50 μA/cm2. Intrinsic size effects have little influence on the linear and non-linear optical absorption of nanocomposites.

Since code-division multiple-access (CDMA) capacity is interference limited, call admission control (CAC) must guarantee both a grade of service (GoS), i.e., the blocking rate, and a quality of service (QoS), i.e., the loss probability of communication quality. This paper describes the development of a new capacity design method based on these two concepts. Theoretical expressions for GoS and QoS as functions of traffic intensity and CAC thresholds are first derived from the traffic theory viewpoint, and then a design method using these expressions is presented. At that time, two strategies for CAC are assumed. One is based on the number of users, and the other is based on the interference level. Computer simulation results are presented that strongly support the proposed design method. Furthermore, numerical examples and a performance comparison of the two strategies considering various propagation parameters, nonuniform traffic distributions, and various transmission rates are shown.

The authors developed an automated 6-row rice transplanter. It has RTKGPS to locate precise position, FOG sensors to measures direction and actuators to control steering, engine throttle, clutch, brake and so on. RTKGPS has 3cm precision at 10Hz data output rate and FOG sensors are issued to restore the inclination of the vehicle. Main computer synchronizes RTKGPS position data with FOG data then it corrects the position error caused by the vehicle inclination. All actuators are controlled by a programmable logic controller (PLC). All control data is sent form main computer to PLC through RS232C. The drift of the FOG sensor was corrected by the using position data. To eliminate the influence of the drift, first, the deviation from the desired path calculated by the yaw angle and vehicle speed was compared with the deviation calculated by GPS data. Then the drift of the heading angle was calculated. The influence of the FOG drift can be eliminated, the authors can correct the FOG drift and the initial error of heading angle and can make long time operation continuously. The experiment was conducted 4 days after puddling. The deviation from the desired straight path was less than 10cm at 0.8m/s of travel velocity. During the rice transplanter went forward and back in a 30m*100m square field 5 times, we obtained satisfactory results.

A method is proposed to synthesize oxide nanoparticles in insulators, using metal-ion implantation and following thermal oxidation, which introduces less damage compared to the sequential implantation of metal ions and oxygen ions. Ni-oxide nanoparticles are formed in O2 gas flow at ∼800°C for 1h, through thermal oxidation of Ni metal nanoparticles, which were introduced in SiO2 by charging-free negative ion implantation of 60keV. After the oxidation, optical absorption in the visible region, which is due to Ni metal nanoparticles in the specimen, disappears, and a steep absorption edge of insulator NiO appears around ∼4eV. Simultaneously, the large magnetization of Ni metal nanoparticles changes to a weak magnetization of antiferromagnetic NiO nanoparticles. The nanoparticle formation is confirmed by transmission electron microscopy observation.

Human six-transmembrane epithelial antigen of prostate 4 (STEAP4) is one of the STEAP family as a homologue of mouse tumour necrosis factor-α-induced adipose-related protein (TIARP). Recently, we reported that the TIARP gene expression was remarkably increased in spleen and joints of glucose-6-phosphate isomerise (GPI)-induced arthritis model, suggesting pivotal association to arthritis. The aim of the present study was to assess the expression, localisation and function of STEAP4 in peripheral blood of patients with rheumatoid arthritis (RA).Peripheral blood was obtained from seven patients with RA, the surface expression of STEAP4 was detected by flow cytometry. The number of neutrophils was compared with the expression of STEAP4 mRNA derived from peripheral blood of patients with RA. Neutrophils were introduced by HL60 with retinoic acid, and were transfected with GFP-STEAP4 plasmid DNA, then the migration of neutrophil-like HL60 was determined by transwell assay. In addition, the fluctuation of STEAP4 mRNA was analysed before and after treatment with infliximab in 40 patients with RA.STEAP4 was expressed on monocytes and neutrophils in peripheral blood in RA. The number of neutrophils and expression of STEAP4 mRNA was positively correlated. Migration of neutrophil-like HL60 was down-regulated by over-expression of STEAP4. Expression of STEAP4 Mrna was significantly decreased after infliximab treatment in patients with RA, especially in good responders.STEAP4 is expressed on monocytes and neutrophils in peripheral blood, regulates cell migration, is down-regulated by TNF antagonist, and might be a possible predictor of response to TNF antagonist.

This paper describes the development of the neutral beam (NB) systems on JT‐60SA, where 30–34 MW D0 beams are required to be injected for 100 s. A 30 s operation of the NB injectors suggests that existing beamline components and positive ion sources on JT‐60U can be reused without the modifications on JT‐60 SA. The JT‐60 negative ion source was modified to improve the voltage holding capability, which leads to a successful acceleration of 2.8 A H− ion beam up to 500 keV of the rated acceleration energy for JT‐60SA.

Voltage holding of -1 MV is an essential issue in development of a multi-aperture multi-grid (MAMuG) negative ion accelerator, of which target is to accelerate 200 A/m{sup 2} H{sup -} ion beam up to the energy of 1 MeV for several tens seconds. Review of voltage holding results ever obtained with various geometries of the accelerators showed that the voltage holding capability was about a half of designed value based on the experiment obtained from ideal small electrode. This is considered due to local electric field concentration in the accelerators, such as edge and steps between multi-aperture grids and its support structures. Based on the detailed investigation with electric field analysis, accelerator was modified to reduce the electric field concentration by reshaping the support structures and expanding the gap length between the grid supports. After the modifications, the accelerator succeeded in sustaining -1 MV for more than one hour in vacuum. Improvement of the voltage holding characteristics progressed the energy and current accelerated by the MeV accelerator. Up to 2010, beam parameters achieved by the MAMuG accelerator were increased to 879 keV, 0.36 A (157 A/m{sup 2}) at perveance matched condition and 937 keV, 0.33 A (144 A/m{sup 2}) slightlymore » under perveance.« less

Acceleration of a 500 keV beam up to 2.8 A has been achieved on a JT‐60U negative ion source with a three‐stage accelerator by overcoming low voltage holding which is one of the critical issues for realization of the JT‐60SA ion source. In order to improve the voltage holding, preliminary voltage holding tests with small‐size grids with uniform and locally intense electric fields were carried out, and suggested that the voltage holding was degraded by both the size and local electric field effects. Therefore, the local electric field was reduced by tuning gap lengths between the large size grids and grid support structures of the accelerator. Moreover, a beam radiation shield which limited extension of the minimum gap length was also optimized so as to reduce the local electric field while maintaining the shielding effect. These modifications were based on the experiment results, and significantly increased the voltage holding from

Excess heat loads to accelerator grids limit extension of pulse length in operation of the large negative ion sources with multi aperture accelerator. Part of the heat loads is caused by interception of deflected beamlets due to their space charge repulsion. In this paper, a beamlet steering technique using aperture offset was examined for compensation of the beamlet deflections utilizing a three dimensional beam analysis simulating the D− negative ion source of JT‐60 U. The beamlet deflection was analyzed in detail using fifty beamlets, which were extracted from apertures arranged in a lattice pattern of 10×5. The simulation showed successful compensation of the beamlet deflection by aperture offsets defined according to the thin lens theory. Even if the beam energy was changed, the necessary aperture offset would not be changed maintaining the perveance and a ratio of extraction and acceleration voltage. In JT‐60 U, it was shown that the aperture offset of less than 1.0 mm would be enough to compensate ...

This paper reports the recent activities at JAEA for the development of 1 MeV H− ion accelerator toward the ITER NBI. For the development of MAMuG accelerator, a 320 mA H− ion beam was successfully accelerated as the highest record in the world at the MeV class energy (796 keV). This was achieved by protecting the H− ion source from the high heat load by the backstream positive ions, which was produced during the high current H− ion acceleration. The SINGAP accelerator was tested at JAEA to compare the performance of the SINGAP and the MAMuG. This paper also reports the results of the SINGAP test and the comparison between the SINGAP and the MAMuG is discussed.

IRFM (CEA Cadarache) and JAEA Naka have entered into a collaboration in order to test a SINGAP [1] accelerator at the JAEA Megavolt Test Facility (MTF) at Naka, Japan. Whereas at the CEA testbed the acceleration current was limited to 0.1 A, at JAEA 0.5 A is available. This allows the acceleration of 15 H‐ beamlets in SINGAP to be tested and a direct comparison between SINGAP and MAMuG [2] to be made. High‐voltage conditioning in the SINGAP configuration has been quite slow, with 581 kV in vacuum achieved after 140 hours of conditioning. With 0.1 Pa of H2 gas present in the accelerator 787 kV could be achieved. The conditioning curve for MAMuG is 200 kV higher. SINGAP beam optics appears in agreement with calculation results. A beamlet divergence better than 5 mrad was obtained. SINGAP accelerates electrons to a higher energy than MAMuG. Measurements of the power intercepted on one of the electron dumps have been compared with EAMCC code [3] calculations. Based on the experiments described here, electron ...

The occurrence of antibodies against recombinant human interferon-alpha 2a (IFN-alpha 2a) in patients with acute viral hepatitis (AVH) was examined by ELISA. Naturally occurring IgG anti-IFN-alpha 2a were found in 50% of patients with type A, 50% of those with type B and in 8.3% of those with non-A, non-B AVH. The corresponding frequencies of IgM antibodies were 80%, 30% and 33.3%, respectively. IgM anti-IFN-alpha 2a were found more frequently in patients with AVH type A than in normal control subjects (P less than 0.01). Anti-IFN-alpha 2a were detectable at the highest frequency 3 weeks after acute onset and then became negative. An absorption experiment revealed that IgM anti-IFN-alpha 2a did not cross-react with recombinant human IFN-alpha 2b. Immunoblotting analysis confirmed the binding of antibodies to IFN-alpha 2a. Sera positive for IgG and/or IgM anti-IFN-alpha 2a were unable to neutralize IFN-alpha 2a. The appearance of anti-IFN-alpha 2a was not correlated with disease severity. There was no evidence to suggest that anti-IFN-alpha 2a impaired the elimination of hepatitis virus. This is the first study to demonstrate the occurrence of anti-IFN-alpha 2a in patients with AVH. Detection of anti-IFN-alpha 2a may be useful for clarifying any underlying immune events in various diseases.

Background & Aims: Clinical significance of molecules involving innate immunity in treatment response remains unclear. The aim is to elucidate the mechanisms underlying resistance to antiviral therapy and predictive usefulness of gene quantification in chronic hepatitis C (CH-C). Methods: We conducted a human study in 74 CH-C patients treated with pegylated interferon α-2b and ribavirin and 5 nonviral control patients. Expression of viral sensors, adaptor molecule, related ubiquitin E3-ligase, and modulators were quantified. Results: Hepatic RIG-I, MDA5, LGP2, ISG15, and USP18 in CH-C patients were up-regulated at 2- to 8-fold compared with nonhepatitis C virus patients with a relatively constitutive Cardif. Hepatic RIG-I, MDA5, and LGP2 were significantly up-regulated in nonvirologic responders (NVR) compared with transient (TR) or sustained virologic responders (SVR). Cardif and RNF125 were negatively correlated with RIG-I and significantly suppressed in NVR. Differences among clinical responses in RIG-I/Cardif and RIG-I/RNF125 ratios were conspicuous (NVR/TR/SVR = 1.3:0.6:0.4 and 2.3:1.3:0.8, respectively). Like viral sensors, ISG15 and USP18 were significantly up-regulated in NVR (4-fold and 2.3-fold, respectively). Multivariate and receiver operator characteristic analyses revealed higher RIG-I/Cardif ratio, ISG15, and USP18 predicted NVR. Lower Cardif in NVR was confirmed by its protein level in Western blot. Also, transcriptional responses in peripheral blood mononuclear cells to the therapy were rapid and strong except for Cardif in not only a positive (RIG-I, ISG15, and USP18) but also in a negative regulatory manner (RNF125). Conclusions: NVR may have adopted a different equilibrium in their innate immune response. High RIG-I/Cardif and RIG-I/RNF125 ratios and ISG15 and USP18 are useful in identifying NVR.

Background/Aims Interferon (IFN) therapy leads to regression of hepatic fibrosis in chronic hepatitis C patients who achieve a sustained virologic response (SVR), while the beneficial effect is limited in those who fail to do so. The aim of the present study was to define factors associated with progression of fibrosis in patients who do not achieve a SVR. Methods Fibrosis staging scores were compared between paired liver biopsies before and after IFN in 97 chronic hepatitis C patients who failed therapy. The mean interval between biopsies was 5.9 years. Factors associated with progression of fibrosis were analyzed. Results Fibrosis progressed in 23%, remained unchanged in 47% and regressed in 29%. Steatosis and a high average alanine aminotransferase (ALT) between biopsies were independent factors for progression of fibrosis with risk ratios of 5.53 and 4.48, respectively. Incidence and yearly rate of progression of fibrosis was 64% and 0.22±0.29 fibrosis units per year in those with both risk factors compared to 8% and −0.04±0.17 fibrosis units per year in those negative for both factors. Conclusions Hepatic steatosis and elevated ALT levels are risk factors for progression of fibrosis in chronic hepatitis C patients who fail to achieve a SVR to IFN therapy and therefore may be therapeutic targets to halt the potentially progressive disease.

This paper reports on the development of compact surface plasmon resonance (SPR) sensors to be used for mobile robot olfaction. The proposed sensor uses a periodic metal structure formed on top of the self-assembled layer of polystyrene particles of 200 nm in diameter. With the grating of this size, SPR can be excited even with an LED light source. The change in the absorbance is simply measured using a photodiode. The experimental results are presented on a silver nanostructure sensor and a gold nanostructure sensor to show the potential of these sensors.

In order to satisfy the expectation of the users to have more advanced wireless access even in the mobile environments, research and development efforts for realizing the fourth-generation (4G) mobile communication system has been discussed. This paper outlines the requirements for the system, technical challenges to be solved, and finally describes the activities related to the standardization of the 4G mobile communication system

The pulse duration of the negative ion based NBI system has been extended from 10 s to 25 s to study long pulse plasmas on JT-60U. A feedback control technique has been demonstrated to keep the arc power constant by controlling the filament voltage for long pulse operation. Thus it was clearly observed that the negative ion beam current increased with the temperature of the plasma grid at constant arc power. A tapered filament is employed to improve its durability for the next operational campaign. Moreover, a high voltage holding test indicates that the reduction in the outgassing from the FRP (fiberglass-reinforced plastic) insulator may be a key to suppress the breakdowns in the ion source

Demand for mobile ad hoc networks (MANET) is increasing. In a MANET, mobile stations communicate with each other by autonomous distributed control. Although flooding is used for discovering a route from a source to a destination, there is the broadcast storm problem when traffic increases rapidly. Besides, there is the hidden terminal problem that packet collisions may be caused in wireless communication. For solving these problems, we propose M-DSMA (MAC protocol using dynamic state transition of mobile stations in ad hoc networks). We define two kinds of states (active state and non-active state) at the mobile station. During the active state, a busy tone is sent as the active state station detects that the channel is busy, and a stop tone is sent as the active state station detects packet collisions. By using two tones, the reachability can be improved.

Broadband CDMA packet access is one of the most promising air interfaces for future 4G mobile communication systems. In this study, a novel reservation-based access protocol with prioritized resource allocation (PRA) is proposed as a reverse channel MAC protocol, which enables various rate real-time communications on such a system. In this protocol, a low-rate temporal dedicated control channel (TDCCH) is momentarily assigned between a base station (BS) and mobile station (MS). A TDCCH is used to transmit not only access control signals including a reservation signal, but also transmission control signals such as transmission power control (TPC) commands. This protocol prevents a packet-by-packet setup delay and provides contention-free packet reservation so long as a TDCCH is established. The duration of the TDCCH can be controlled according to the quality of service (QoS) requirement. PRA is based on such a reservation scheme, and two different resource allocation areas are defined in time slots that correspond to real-time and best-effort classes. The real-time packets have a wider allocation area so that they can acquire radio resources prior to best-effort packets. Thus, resources are assigned to real-time packets first, and the remaining resources can be used for best-effort packet transmission. By combining admission control and flow control with PRA, real-time packet communication can be achieved in the reverse channel. The performance of the proposed protocol is evaluated by computer simulation and through an experimental system.

A novel wireless QoS architecture suitable for broadband CDMA packet cellular systems is proposed and its characteristics are described. The proposed QoS architecture is composed of several control factors laid on MAC and RRC layers, and can be harmonized with IP-QoS. Two important control factors, i.e., radio condition aware admission control and resource allocation reflected hybrid scheduling, are proposed. Computer simulations and testbed experiments indicate that by using radio condition aware admission control, stable and guaranteed service can be provided to realtime users regardless of interference and location variation of the mobile station. Moreover, resource allocation reflected hybrid scheduling maintains guaranteed rates for realtime users and provides high resource utilization efficiency for best effort users. Consequently, by using the proposed wireless QoS architecture, it is possible to provide users with high quality and diversified realtime services, on a packet based radio network for 3.5G and 4G.

A multihop connection scheme, where one or more mobile terminals relay transmission signals using the same access scheme between an end user terminal and its destination base station, is a promising approach to overcome reduction in cell size caused by high bit-rate data transmission. In a general radio communication system, coverage area and system throughput are closely interrelated. In this paper, the performance of a multihop cellular network employing a CDMA access scheme, which is a promising candidate for beyond the third generation, is studied in terms of coverage area and system throughput by conducting a link level simulation. The results show that a multihop connection expands a coverage area, especially in a light traffic case, and also has an advantage in system throughput.

Recently many groups have started studies of formation of zinc-oxide (ZnO) nanoparticle (NP) in transparent insulators, such as silica glass, sapphire, etc, using ion implantation techniques. In the early half of this article, we shortly review recent activities of ZnO NP formation using ion implantation combined with thermal oxidation. Some groups succeeded but the others did not. Even if they succeeded in the formation of ZnO nanostructures, one reported that they were in the shape of thin film and another reported the NP form. Based on our recent experimental results, we point out the importance of the oxidation temperature and the peculiar shapes and depth profiles of ZnO formed.

High-porosity nanoporous silica was prepared by nanocasting method using N-isopropylacrylamide (NIPAm) cross-linked by N, N’-methelenbisacrylamide (BIS) as the templating agent. The obtained silica was a bulk silica with good transparency indicating that the characteristic length-scale of the obtained silica is in the nanoscopic scale being much smaller than that of the wave length of visible light. Nitrogen adsorption/desorption measurements revealed that the nano porosity increases up to 80% with the weight ratio of NIPAm to silica. The mean pore size (radius) also increased with the weight ratio in the region smaller than 10nm. TEM observation revealed that the nanoscopic network structure was replicated into tube-like nanopores randomly distributed in the silica matrix. The whole nanoscopic morphology of these tube-like nanopores was much like as the predicted for the cross-linked polymer.

In the operation of hierarchical mobile IPv6 (HMIP) (H. Soliman, et al., 2003), a mobile node (MN) is supposed to send binding updates (BUs) to the home agent (HA) and a mobility anchor point (MAP); therefore, a MAP discovery protocol is needed to facilitate MN discovery of MAPs. Two protocols were previously proposed in (H. Soliman, et al., 2003) for MAP discovery, however, in both protocols, all access routers (ARs) must issue router advertisements (RAs) with MAP information option fields in order for the MNs to receive them. In such MAP discovery protocols, ARs must be aware of HMIP operation for the advertising of MAP information. In this paper, we introduce a new MAP discovery protocol that is transparent to ARs. Such transparency would bring about wider applicability for HMIP than previously achieved, which is important from industrial and commercial viewpoints. In addition, we confirm that the proposed protocol meets the requirements, and we evaluate its performance by computer simulation.

Mobility support for mobile networks will be more important as the mobile Internet becomes increasingly popular. To support mobile networks, the concept of prefix scope binding (PSB) is being discussed in IETF; however, by only applying this concept to Mobile IPv6 (MIP), the problem of packet loss still remains. In this paper, we apply the PSB concept to our proposed protocol, the hierarchical Mobile IPv6 extension with buffering function (HMIP-B), in which mobility anchor points buffer packets destined to the mobile hosts during handoff. We compare MIP and HMIP-B based on the handoff performance related to mobile networks by computer simulation. The simulation results indicate that our proposal improves the handoff performance in both TCP and UDP communications.