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This paper presents the dependence of the stress intensity factor on a geometrical factor estimated by fracture mechanics analysis around the defect in the butt joint weld of a cable-in-conduit conductor (CICC) of a superconducting coil. The stress intensity factor can be estimated by the Newman–Raju equation applied to the CICC section, but the effect of the difference between the geometry assumed in the equation and the actual CICC geometry has not been clarified yet. Therefore, the three-dimensional finite element method (3D-FEM) is performed to estimate the geometrical factor. As a result, the Newman–Raju equation is considered to be applicable for the assessment of the fracture toughness of the rectangular-shaped conduit because the maximum stress intensity factor by 3D-FEM is only 3% larger than that determined by the Newman–Raju equation for the maximum postulated defect.

The critical beta, which is limited by an external kink mode with Alfven wave time scale, is shown to be decreased by ferromagnetic effect by about 8% for μ/μ0 ~ 2 where μ and μ0 denote the permeability of a ferromagnetic wall and vacuum, respectively, for a tokamak of aspect ratio 3. The existence of the stability window in the wall distance for resistive wall mode opened by the effects of both the toroidal plasma rotation and the plasma dissipation, which was not observed for the high aspect ratio tokamak, is found for the tokamak of aspect ratio 3. The effect of ferromagnetism on them is also investigated. The critical beta analyses of the National Centralized Tokamak (NCT) plasma using the VALEN code are started by stabilizing plate and vacuum vessel geometry with finite resistivity, and the results of the passive effect of the stabilizing plate are obtained. The calculations including the stabilizing effect of the vacuum vessel and also active feedback control are performed for a design of the NCT plasma.

Objective: We investigated the role of antioxidants in airway hyperresponsiveness to acetylcholine using young asthma model mice, which were sensitized and stimulated with ovalbumin. Methods: The mice had been fed either a normal diet, an α-tocopherol-supplemented diet or a probucol-supplemented diet 14 days before the first sensitization. They were immunized with antigen at intervals of 12 days and, starting from 10 days after the second immunization, they were exposed to antigen 3 times every 4th day using an ultrasonic nebulizer. Twenty-four hours after the last antigen inhalation, airway responsiveness to acetylcholine was measured and bronchoalveolar lavage fluid (BALF) was collected. A blood and lung tissue study was also carried out. Results: Twenty-four hours after the last antigen challenge, both IL-4 and IL-5 in the BALF of α-tocopherol-supplemented mice were significantly decreased. The IL-5 level in probucol-supplemented mice was also decreased, but there was no difference in IL-4 levels. The serum IgE level was decreased in probucol-supplemented mice. Differential cell rates of the fluid revealed a significant decrease in eosinophils due to antioxidant supplementation. Airway hyperresponsiveness to acetylcholine was also repressed in antioxidant-supplemented mice. In histological sections of lung tissue, inflammatory cells and mucus secretion were markedly reduced in antioxidant-supplemented mice. We investigated the antioxidant effect on our model mice by examining 8-isoprostane in BALF and lung tissue, and acrolein in BALF; however, our experiment gave us no evidence of the antioxidant properties of either α-tocopherol or probucol contributing to the reduction of airway inflammation. Conclusion: These findings indicate that α-tocopherol and probucol suppress allergic responses in asthma model mice, although these two drugs cause suppression in different ways that are unrelated to antioxidation.

Cholelithiasis is one of the side-effects of ceftriaxone (CTRX). Reportedly, the cholelithiasis resolves relatively soon after cessation of CTRX, hence, it is called pseudolithiasis. Previous reports have suggested that biliary pseudolithiasis can cause not only gallstone attacks, but also severe adverse events, such as cholecystitis and pancreatitis. The purpose of this study was to prospectively elucidate the risk factors and clinical features of CTRX-associated pseudolithiasis in pediatric patients.We prospectively examined the incidence and clinical outcome of CTRX-associated biliary pseudolithiasis. Subjects included infants and children who were admitted to hospital with acute disease. Ultrasonography was used to confirm the absence of stones and sludge in the gallbladder before CTRX therapy, and in assessment of pseudolithiasis on days 3, 5, 7 and 10 after initiation of CTRX in all subjects. The pseudolithiasis group was then compared with the non-pseudolithiasis group in terms of age, sex, CTRX dose, CTRX duration, duration of fever, fasting period, period of bed rest, and blood test results.Sixty patients were enrolled in the study. Eleven of them had biliary pseudolithiasis on ultrasonography (18.3%). Formation of biliary pseudolithiasis was prevalent in the fasting and bed rest groups, appearing relatively early in these groups.Special attention should be paid to the degree of oral intake and patient activity when CTRX is prescribed. We recommend regular ultrasonographic follow up of patients receiving CTRX, to evaluate the formation of biliary pseudolithiasis.

The aim of this study was to assess the rate of response to long-term low-dose levetiracetam (LEV) treatment and the clinical factors associated with response.The response to low-dose LEV of 43 patients with epilepsy (22 male, 21 female; age range, 5-39 years; median age, 13 years) was retrospectively assessed. Patients aged15 years received20 mg/kg/day LEV, whereas those aged ≥15 years received1000 mg/day LEV. Clinical features were compared between responders to low-dose LEV, responders to the recommended dose, and non-responders.Of the 43 patients who received low-dose LEV, 13 (30%) showed improvement, defined as seizure cessation or75% seizure reduction over 6 months for patients with monthly, weekly, and daily seizures; and over 1 year for patients with yearly seizures. Efficacy was maintained for1 year in 10 (77%) of the 13 patients. Long-term response to low-dose LEV was significantly associated with older age at onset and fewer previous treatments with ineffective anti-epileptic drugs. All patients showing long-term response to low-dose LEV developed only focal seizures.Titration of LEV starting from a low dose may be effective in selected patients. Once patients respond to low-dose treatment, maintenance of the effective dosage may prolong response.

Rotavirus gastroenteritis is severe and often results in dehydration and pre-renal azotemia. In addition, some patients with acute obstructive uropathy due to ammonium acid urate stones, developing approximately 6-7 days after the onset of rotavirus gastroenteritis, have been reported, mainly in Japan. The pathophysiological mechanism responsible for stone formation has not been clarified. In the present study, we investigated the clinical characteristics of these patients, and analyzed the pathophysiology underlying the formation of urinary stones.A total of 164 patients were enrolled. All had acute gastroenteritis due to rotavirus infection and were treated at Osaka Medical College Hospital and affiliated hospitals between January 2009 and May 2011. All were younger than 15 years of age, and their laboratory data, including urinalysis, were available.Among the enrolled patients, 30 (20 boys and 10 girls aged 0.2-10 years; median, 1.5 years; interquartile range, 1-3 years) had crystals in their urine. Most of the patients were admitted approximately 2 days after onset of gastroenteritis and had hyperuricemia and aciduria. The crystals consisted mainly of uric acid, and rarely of ammonium acid urate.In order for ammonium acid urate stones to form in patients with acute obstructive uropathy associated with rotavirus gastroenteritis, prolonged continuous acidosis with hyperuricemia, might be necessary. Therefore, normalization of metabolic acidosis is important in order to prevent the onset of obstructive uropathy associated with rotavirus gastroenteritis.

The effects of valproic acid (VPA) on oxidative stress are controversial due to differences in experimental conditions. Recently, total hydroxyoctadecadienoic acid (tHODE), derived from linoleic acid, was proposed as a potent biomarker to evaluate oxidative stress.The subjects consisted of 10 new-onset epilepsy patients treated with VPA. We measured plasma tHODE consecutively for 1 year to evaluate the degree of oxidative stress and then compared plasma tHODE at the beginning and the end of experiments with the peak level. Ten age-matched healthy subjects were recruited as a control group and their plasma tHODE was compared to the initial plasma tHODE of the epilepsy group. Measurements were done using liquid chromatography-tandem mass spectrometry.Mean initial plasma tHODE in the epilepsy group was 165.2 ± 76.8 nmol/L, which was not significantly different from that of the control group (199.3 ± 62.5 nmol/L). In five epilepsy patients, plasma tHODE increased above the pathological level in 6 months, but returned to normal within 1 year. In the whole group, the difference plasma tHODE between peak, at the beginning and 1 year later, was significant.Oxidative stress generated by VPA increased temporarily, but decreased to normal after 1 year. it is reasonable to be concerned about the effects of oxidative stress, especially at the start of VPA treatment.

Design studies are shown on the National Centralized Tokamak facility, formerly called JT-60SC. The machine design is carried out to investigate the capability for flexibility in aspect ratio and shape controllability for the demonstration of the high-β steady state operation with nation-wide collaboration, in parallel with ITER towards DEMO. Two designs are proposed and assessed with respect to the physics requirements such as confinement, stability, current drive, divertor and energetic particle confinement. The operation range in the aspect ratio and the plasma shape is widely enhanced consistent with sufficient divertor pumping. Evaluations of the plasma performance towards the determination of the machine design are presented.

Advanced technologies for fabrication of superconducting coils have been developed for the National Centralized Tokamak which is based on modification of JT-60. One of the technologies developed is the application of the react-and-wind (R&W) method of fabrication of a Nb3Al D-shaped coil. The bending strain of 0.4% due to the R&W method did not affect the critical current characteristics. This finding indicates the possibilities that the manufacturing cost of large size coils can be reduced further by downsizing the heat treatment furnace, and large complicated shape coils can be manufactured by using the Nb3Al conductor. Another technology is an advanced winding technique for the reduction of the ac losses of Nb3Sn coils by loading bending strain on the conductor. It was found that 0.2% bending strain is enough to reduce the ac losses to one-fifth at the virgin state. The newly developed NbTi conductor attained both (i) low ac loss of 116 ms in coupling time constant and (ii) low cost owing to the stainless steel wrap of the sub-cables and Ni plated NbTi strands with 11 µm filaments.

The hydroxyl (OH) radical, which is generated in polluted dew water on leaf surfaces of the Japanese apricot (Prunus mume), is known to be a potent oxidant. In order to investigate the effects of the OH radical formed in polluted dew water on the photosynthesis and growth of 3-year-old seedlings of P. mume, OH radical-generating solutions simulating polluted dew water were sprayed in the early morning as a mist throughout a growing season onto the leaf surfaces of seedlings growing in experimental greenhouses. Four OH radical-generating solutions (0, 6, 18 and 54 μM H2O2 with Fe(III) and an oxalate ion) were used in the mist treatment. Five months after the beginning of treatment, the leaves exposed to the mist containing 54 μM H2O2 showed a significantly smaller maximum CO2 assimilation rate (Amax) and stomatal conductance (gs) as compared to the leaves exposed to the mist containing 0 μM H2O2. Exposure of P. mume seedlings to the OH radical-generating mist had caused a reduction in the dry weight and relative growth rate (RGR) of the above-ground parts (stem + branch) at the end of the growing season. A significant positive correlation was shown between RGR and Amax. Thus, the effects of oxidants generated in polluted dew water on leaf surfaces can be considered to be a cause of the decrease in leaf photosynthesis and growth of P. mume.

The analgesic effect of oral sucrose in newborn infants undergoing painful procedures is generally accepted. For blood sampling, some studies have shown that venepuncture (VP) is less painful than heel lance (HL).To determine the least painful and most effective method among blood sampling by VP or HL with or without sucrose.Randomised, double blind, placebo controlled trial.A total of 100 healthy, full term newborn infants being screened for inborn errors of metabolism were randomly allocated to one of four experimental groups (25 infants in each). Intervention andSeven specially trained nurses took turns to carry out blood sampling two minutes after administration of oral sucrose or water. Neonatal pain was assessed by the neonatal facial coding system (NFCS), as well as by crying.Without sucrose, the NFCS score was higher in the HL group than the VP group during blood sampling (median 58 v 23, p0.001). Oral sucrose significantly reduced the score of the HL group (58 v 47, p0.01) and also tended to reduce the score of the VP group (23 v 2, p0.1). However, the HL with sucrose group still had a higher score than the VP without sucrose group (47 v 23, p0.01). Crying and the total procedure time showed the same trends as the NFCS score.VP is less painful and more effective than HL for blood sampling in newborn infants. Although oral sucrose may have an additive analgesic effect, it is not necessarily required if VP is used for blood sampling.

The bioavailability of gamma-tocopherol and metabolites of vitamin E after gamma-tocopherol administration is not well understood. We investigated the effect of gamma-tocopherol administration on the levels and metabolism of alpha- and gamma-tocopherol in healthy volunteers.We measured two metabolites of vitamin E (2,5,7,8-tetramethyl-2-(2'-carboxyethyl)-6-hydroxychroman (alpha-CEHC) and 2,7,8-trimethyl-2-(2'-carboxyethyl)-6-hydroxychroman (gamma-CEHC)) in plasma and urine by high-performance liquid chromatography with electrochemical detection (HPLC-ECD) during administration of gamma-tocopherol. Two groups of volunteers were enrolled. The gamma-tocopherol group received two gamma-tocopherol capsules (each containing 186.4 mg of gamma-tocopherol and 5 mg of alpha-tocopherol) for 28 days, while the control group received d-alpha-tocopherol at 5 mg/day, which was the same dose as that given to the gamma-tocopherol group. Blood and urine samples were obtained on days 0, 14, 28, 35, 42, and 56 after the initiation of gamma-tocopherol administration.The plasma gamma-tocopherol concentration increased markedly during administration of gamma-tocopherol and the plasma gamma-CEHC concentration increased along with that of gamma-tocopherol. The plasma alpha-tocopherol concentration decreased significantly during gamma-tocopherol administration. The plasma concentration of alpha-CEHC decreased significantly and urinary excretion of alpha-CEHC tended to increase in the gamma-tocopherol group. Urinary sodium secretion was significantly increased at 1 week after the cessation of gamma-tocopherol administration, but there was no significant difference of urine volume between the two groups.Metabolism of alpha-tocopherol is accelerated and the plasma alpha-tocopherol concentration is decreased during gamma-tocopherol administration.

Argon, krypton and xenon were puffed with and without simultaneous hydrogen gas puffing into Ohmically heated plasmas of the JT-60U tokamak with low plasma currents in order to study the capability of disruption mitigation. It was found that krypton gas puffing can provide a plasma termination with smaller amounts of runaway electrons in comparison to argon and xenon gas puffing.

Reactive oxygen species (ROS) may contribute to aging and osteoporosis resulting from marked decreases in plasma antioxidants in aged osteoporotic women. On the other hand, high-dose vitamin K2 (menaquinone-4: menatrenone, MK-4) supplementation has been reported to reduce ovariectomy-induced bone loss in rats and to decrease osteoporotic fracture in postmenopausal women. However, the mechanism by which vitamin K2 prevents osteoporosis is unclear. Recently, vitamin K2 has been suggested to preserve antioxidant activity as a novel function. Therefore, we investigated the effect of vitamin K2 on the osteoporosis of aged rats by evaluating the relationships between serum antioxidant levels and bone metabolism. Aged female rats exhibited significantly lower serum alkaline phosphatase activity and osteocalcin level, together with lower serum levels of antioxidants such as 17beta-estradiol, macrophage migration inhibitory factor (MIF) and glutathione peroxidase (GPx) activity, as compared with young female rats. On the other hand, vitamin K2 supplementation (500 mg/kg, food intake) for 98 days led to a significantly increased serum vitamin K2 level (3,045+/-915 ng/ml in the vitamin K2 supplemented group vs. 4.6+/-3.4 ng/ml in the control diet group; P

Objectives: To determine the serum ratio of holo-ceruloplasmin to total ceruloplasmin in patients with Wilson's disease (WD), we identified apo- and holo-forms of serum ceruloplasmin with native-PAGE electrophoresis. Design and methods: Serum obtained from nine patients with Wilson's disease was subjected to native-PAGE analysis. We also determined the ceruloplasmin level and ferroxidase activity in all of the samples. Results: Among the nine patients, three had both forms of ceruloplasmin and six had only apo-ceruloplasmin. In the patients who had only apo-ceruloplasmin, the serum ceruloplasmin level was significantly lower than in the patients with both forms. Conclusions: Differences in the ability to incorporate copper into ceruloplasmin may have a role in ceruloplasmin concentrations in patients with Wilson's disease.

Characteristics of post-disruption runaway electrons with impurity pellet injection were investigated for the first time using the JT-60U tokamak device. A clear deposition of impurity neon ice pellets was observed in a post-disruption runaway plasma. The pellet ablation was attributed to the energy deposition of relativistic runaway electrons in the pellet. A high normalized electron density was stably obtained with nebar/nGW ˜ 2.2. Effects of prompt exhaust of runaway electrons and reduction of runaway plasma current without large amplitude MHD activities were found. One possible explanation for the basic behavior of runaway plasma current is that it follows the balance of avalanche generation of runaway electrons and slowing down predicted by the Andersson-Helander model, including the combined effect of collisional pitch angle scattering and synchrotron radiation. Our results suggested that the impurity pellet injection reduced the energy of runaway electrons in a stepwise manner.

A 7-year-old Japanese female diagnosed as having acute disseminated encephalomyelitis presented seizures, visual symptoms, and hypersomnia with bilateral lesions in the white matter, basal ganglia, and hypothalamus. Her clinical findings and demonstrated lesions in neuroimages were similar to those of Von Economo's encephalitis lethargica. Her hypocretin, the hypothalamic neuropeptide controlling sleep-awake cycle, was significantly low in the cerebrospinal fluid (146 pg/mL) on admission. Successive measures resulted in the gradual recovery of cerebrospinal fluid hypocretin to the normal range (263 pg/mL) as her excessive daytime sleepiness was reduced. Decreased hypothalamic hypocretin neurotransmission may be involved in this symptomatic case of hypersomnia associated with acute disseminated encephalomyelitis.

Nonsteroidal anti-inflammatory drugs (NSAIDs) induce apoptosis in a variety of cells, but the mechanism of this effect has not been fully elucidated. We report that diclofenac, a NSAID, induces growth inhibition and apoptosis of HL-60 cells through modulation of mitochondrial functions regulated by reactive oxygen species (ROS), Akt, caspase-8, and Bid. ROS generation occurs in an early stage of diclofenac-induced apoptosis preceding cytochrome c release, caspase activation, and DNA fragmentation. N-Acetyl-L-cysteine, an antioxidant, suppresses ROS generation, Akt inactivation, caspase-8 activation, and DNA fragmentation. Cyclic AMP, an inducer of Akt phosphorylation, suppresses Akt inactivation, Bid cleavage, and DNA fragmentation. LY294002, a PI3 kinase inhibitor, enhances Akt inactivation and DNA fragmentation. Ac-IETD-CHO, a caspase-8 inhibitor, suppresses Bid cleavage and DNA fragmentation. z-VAD-fmk, a universal caspase inhibitor, but not cyclosporin A (CsA), an inhibitor of mitochondrial membrane permeability transition, suppresses DNA fragmentation. These results suggest the sequential mechanism of diclofenac-induced apoptosis of HL-60 cells: ROS generation suppresses Akt activity, thereby activating caspase-8, which stimulates Bid cleavage and induces cytochrome c release and the activation of caspase-9 and-3 in a CsA-insensitive mechanism. Furthermore, we found that 2-methoxyestradiol (2-ME), a superoxide dismutase inhibitor, significantly enhances diclofenac-induced apoptosis; that is, diclofenac combined with 2-ME may have therapeutic potential in the treatment of human leukemia.

The neutron penetration and the activation characteristics of the boron-doped low activation concrete were investigated for irradiation of 2.45 and 14 MeV neutrons. The shielding property of the 2 wt% boron-doped low activation concrete is superior to that of the 1 wt% boron for the thermal neutron, on the contrary to no clear difference for the fast neutron. The total activity detected in the boron-doped low activation concrete was about one hundredth of that in the geostandard sample at more than 30 days cooling time. The total activity of the boron-doped concrete by major nuclei does not depend on the boron density for the 14 MeV neutron irradiation.

Japan Atomic Energy Research Institute (JAERI) plans to construct a tokamak fusion device called JT-60SC in which superconducting magnet systems will be used. The purpose in this paper is to qualify type 316LN stainless steel (SS316LN) for use as the conduit material of the Nb3Sn cable-in-conduit conductor for the central solenoid (CS) of JT-60SC. Tensile properties, fracture toughness and fatigue crack growth rates of the as-welded metal and the aged (923 K × 240 h) one of SS316LN were evaluated at 4 K. The tensile properties and fatigue crack growth rates were adequate to ensure the design requirements for JT-60SC. However, fracture toughness of the aged weld metal could not be validated due to unstable crack growth. It was concluded that improvement of fracture toughness after aging was required to ensure the structural integrity of the CS conduit.

Plasma control on high-βN steady-state operation for JT-60 superconducting modification is discussed. Accessibility to high-βN exceeding the free-boundary limit is investigated with the stabilising wall of reduced-activated ferritic steel and the active feedback control of the in-vessel non-axisymmetric field coils. Taking the merit of superconducting magnet, advanced plasma control for steady-state high performance operation could be expected.

The modification of JT-60 to a full superconducting tokamak (JT-60SC) is being planned. The support structures of the TF coils are designed to withstand the large electromagnetic force on the basis of the stress analyses. Shear panels are inserted between the neighboring TF coils against the overturning force and settled after the installation of the peripheral components like NBI ports. The maximum displacement and the Tresca stress of the TF coil have been evaluated in the case of the plasma disruption at the end of plasma current flat-top. In order to analyze the profiles of stress and displacement in detail, the bolts tightening the shear panel are considered in the FEM model. The maximum displacement of a TF coil is evaluated to be about 8.8 mm that is within the design requirement to keep space between the coils and the peripheral ports. The peak Tresca stress of 611 MPa appears at a bolt on the shear panel at the lower midplane. This value is within the allowable stress of SS316LN at 4 K, 667 MPa. In addition, the analyses for the various plasma operations, especially for the high poloidal beta (/spl sim/2) plasma operation, were carried out and the validity of the support structure was confirmed.

A 1.5-dimensional time-dependent transport analysis has been carried out to investigate steady-state operation scenarios with a central current hole by off-axis current drive schemes consistent wit...

Development of Nb/sub 3/Sn cable-in-conduit (CIC) conductors with stainless steel (SS) jackets for the central solenoid (CS) and divertor coil of the superconducting tokamak called JT-60SC, is presented. Full-size and subsize conductors were manufactured using two types of high-copper-ratio and high-J/sub c/ strands made by different processes (bronze and internal-tin). Use of a SS jacket causes decrease of critical current of the conductor because compression strain due to difference of the thermal contraction between the SS jacket and Nb/sub 3/Sn cable is generated. The strains are estimated from the results of critical current measurements using short full-size samples which were pool-cooled. In order to investigate J/sub c/-B-T characteristics of a CIC conductor, a novel apparatus, which can control the temperature and magnetic field, has been developed. This apparatus makes it possible to measure directly the critical current and temperature of a subsize conductor, which is composed of two superconducting strands, one copper wire and a SS jacket. Strains of the subsize conductors are estimated from the results of the J/sub c/-B-T characteristic measurements. By comparison of the estimated strains between the full-size and subsize samples, we concluded that the characteristics of the full-size conductor can be predicted by measuring of J/sub c/-B-T characteristics of subsize conductors. Finally, the strain of the actual conductor under the operational condition is estimated. The result confirms that the developed conductors are applicable to CS and divertor coil of JT-60SC.

Using a 20 kA Nb/sub 3/Al cable-in-conduit (CIC) conductor, a two-turn D-shaped test coil with a height of 2.0 m and a width of 1.8 m was fabricated by a react-and-wind (R&W) method. After heat treatment, the conductor was formed to the D-shaped coil. Bending strain of the conductor is /spl plusmn/0.4% at critical current I/sub c/ test section. The I/sub c/ exceeded 31.4 kA at 7.3 T, 4.2 K. In spite of the stainless steel conduit, a critical current density J/sub c/ of 89% of the strand value was attained. The total strain of the D-shaped test coil was about -0.57%, the same as the triplex-CIC sample fabricated by a W&R method, indicating that bending did not influence the I/sub c/. The I/sub c/ at 7.4 T, 5.6 K including the margin of 1 K exceeds the operational current. Therefore, it was concluded that the R&W method is quite appropriate for the toroidal field coil of JT-60SC.

The neutron shielding design has been carried out for the JT-60 superconducting modification using the boron-doped resin. For the boron doped resin with 0.8 and 2 wt % boron, the neutron transmission experiment with 2.45 MeV neutron source has been performed. The shielding performance of the boron-doped resin for the fast neutron flux does not depend on the boron density in the range of 0.8-2 wt% boron. On the other hand, for the thermal neutron flux the shielding performance of 2 wt% boron is superior to that of 0.8 wt% boron. Most of the reaction rates by DOT3.5 and MCNP calculations agree with the experiment results within 20 %.

Modification of JT-60 as a full superconducting tokamak (JT-60SC) is planned. The objectives of the JT-60SC programme are to establish scientific and technological bases for steady-state operation of high performance plasmas and utilization of reduced-activation materials in an economically and environmentally attractive DEMO reactor. Advanced fusion technologies relevant to the DEMO reactor have been developed for the superconducting magnet technology and plasma facing components of the JT-60SC design. To achieve a high current density in a superconducting strand, Nb3Al strands with a high copper ratio of 4 have been newly developed for the toroidal field coils (TFCs) of JT-60SC. The R&D to demonstrate the applicability of the Nb3Al conductor to TFCs by a react-and-wind technique has been carried out using a full-size Nb3Al conductor. A full-size NbTi conductor with low ac loss using Ni-coated strands has been successfully developed. A forced cooling divertor component with high heat transfer using screw tubes has been developed for the first time. The heat removal performance of the carbon fibre composite target was successfully demonstrated on an electron beam irradiation stand.

The analyses of the plasma position and shape control in the superconducting tokamak JT-60SC in JAERI are presented. The vacuum vessel and stabilizing plates located closely to the plasma are modeled in 3 dimension, and we can take into account the large ports in the vacuum vessel. The linear numerical model used in the design for the plasma feedback control system is based on Grad–Shafranov equation, which allows the plasma surface deformation. For a slower control of the plasma shape, the superconducting equilibrium field (EF) coils outside toroidal field coils are used, while for a fast control of the plasma position, in-vessel normal conducting coils (IV coil) are used. It is shown that the available loop voltages of the EF and IV coils are very limited, but there are sufficient accuracy and acceptable response time of plasma position and shape control.

Alpha-tocopherol transfer protein (alpha-TTP), a 30 kDa cytosolic protein first described to be present in the liver and important for alpha-tocopherol trafficking, plays a major role in maintaining alpha-tocopherol levels in plasma, while alpha-tocopherol is known as the major lipid-soluble antioxidant. Expression of alpha-TTP has not only been described in animal model liver, but also in diverse other tissues such as rat brain or pregnant mouse uterus, the latter finding stressing the importance of alpha-TTP for embryogenesis and foetal development. In this study, we report the identification of alpha-TTP in human liver by anti-human alpha-TTP monoclonal antibodies made in rat and the cellular localization of alpha-TTP in term human placenta. By immunohistochemistry, intense staining of alpha-TTP was seen in syncytiotrophoblast as well as in villous and invading extravillous cytotrophoblast, while basal decidual cells showed slighter, but present staining of alpha-TTP. Foetal vessel endothelium remained unstained. It is therefore suggested that alpha-TTP may play a major role in supplying alpha-tocopherol to the foetus prior to delivery and is likely involved in maintaining adequate alpha-tocopherol levels in the foetus.

Among various hypothetical mechanisms for the in vivo production of reactive oxygen species, transition metal-catalyzed reactions in cooperation with a biologic reducing agent like ascorbic acid or superoxide may be some of the most important. In the present study, we retrospectively examined the existence of non-protein-bound metal ions, an essentially hazardous pro-oxidant form of various transition metals, and the occurrence of metal-catalyzed reactive oxygen species production in cerebrospinal fluid (CSF) of 10 infants with hypoxic ischemic encephalopathy (HIE) subsequent to perinatal asphyxia and 12 control infants within 72 h of birth. Non-protein-bound iron was detected in eight out of 10 CSF samples from the HIE infants and its level was significantly correlated with Sarnat's clinical stage, whereas none of the control infants had detectable non-protein-bound iron levels. Non-protein-bound copper was below the detection limit in all CSF samples from both groups. Ascorbic acid was significantly increased in the CSF of HIE infants when compared with that of controls (means, 664.9 versus 449.4 microM, p = 0.008). ortho-Tyrosine and meta-tyrosine, which are highly specific and sensitive markers of protein oxidation induced by hydroxyl radicals, were significantly higher in HIE infants than in controls when evaluated by the ratio relative to their source amino acid, phenylalanine [means, 110.5 versus 75.4, p = 0.018 for ortho-tyrosine/phenylalanine; 104.6 versus 67.7 (nM/microM x 10(2)), p = 0.048 for meta-tyrosine/phenylalanine]. Both ratios were significantly correlated with non-protein-bound iron, but not with ascorbic acid. Our preliminary observations provide direct evidence that hydroxyl radicals are generated in the CNS during asphyxiation. Iron chelation therapy could be worth developing as a neuroprotective strategy for perinatal asphyxia.

The capability of detachment control in JT-60SC is demonstrated with a divertor code (SOLDOR/NEUT2D). Under the standard operation of the core edge density at 95% of the minor radius, n edge = 3.2 x 10 19 m 3 , the power flow from the core plasma Q c = Q i = 6 MW, and the conductance of inner and outer cryopanels C in = C out = 50 m 3 /s, the inner divertor plasma is partially detached and the outer divertor plasma attached. The inner divertor can be changed from partially detached to attached plasma by inner pump of 150 m 3 /s. The fully detached inner divertor is obtained in high density operation with n sep > 4 x 10 19 m 3 , where n sep is the density at the separatrix outer midplane, The elastic collision in a dense and cold divertor plasma (n c ≥ 5 x 10 20 m 3 . T c < 5 eV) play an important role on detachment.

In ELMy H-mode plasmas of Japan Atomic Energy Research Institute Tokamak-60 Upgrade, extension of a high confinement regime toward high density and high radiation-loss-power fraction has been investigated by Ar injection. With injecting Ar and putting the outer strike point on the top of divertor dome, confinement improvement, electron density, and radiation-loss-power fraction reached the ITER relevant regime; the thermal energy confinement time was as high as that the International Tokamak Experimental Reactor ELMy H-mode scaling IPB98(y,2), the electron density is ∼80% of the Greenwald density, and the radiation-loss-power fraction is ∼0.8. Although electron density profile is slightly peaked with Ar injection, the confinement improvement is mainly attributed to the improvement of ion transport. Moreover, the maximum divertor heat load due to ELMs has been reduced by a factor of 3–5 with keeping high confinement. ELM activity can be controlled by injecting Ar and changing the strike point position.

Two-dimensional (2D) reconstruction software was developed for bolometer signals of the JT-60U tokamak. Radiative divertor plasma with emissivity of 10 MW m −3 was found previously to extend 10 cm from the target plates. When the density is increased further by larger gas puffing, the emissivity imbalance between both divertor legs becomes less significant. The radiative zones move upward along the divertor legs and eventually merge into a single bright peak near the X-point at density around 6×10 19 m −3 called X-point multifaceted asymmetric radiation from edge. Upward movement of the radiation peak during detachment is sometimes observed directly by the in-vessel bolometer. Total radiated power at the divertor saturates at a certain level while the core radiation continues to increase with the density. Although the 2D profile of the divertor radiation undergoes dramatic changes near the saturation, the energy confinement appears to degrade with density increase irrespective of these changes.

Alpha-tocopherol (a form of vitamin E) is a fat-soluble vitamin that can prevent lipid peroxidation of cell membranes. This antioxidant activity of alpha-tocopherol can help to prevent cardiovascular disease, atherosclerosis and cancer. We investigated the alpha-tocopherol level and the expression of alpha-tocopherol transfer protein (alpha-TTP) in the leukocytes of children with leukemia. The plasma and erythrocyte alpha-tocopherol levels did not differ between children with leukemia and the control group. However, lymphocytes from children with leukemia had significantly lower alpha-tocopherol levels than lymphocytes from the controls (58.4 +/- 39.0 ng/mg protein versus 188.9 +/- 133.6, respectively; p < 0.05), despite the higher plasma alpha-tocopherol/cholesterol ratio in the leukemia group (5.83 +/- 1.64 micromol/mmol versus 4.34 +/- 0.96, respectively; p < 0.05). No significant differences in the plasma and leukocyte levels of isoprostanes (the oxidative metabolites of arachidonic acid) were seen between the leukemia patients and controls. The plasma level of acrolein, a marker of oxidative stress, was also similar in the two groups. Investigation of alpha-TTP expression by leukocytes using real-time PCR showed no difference between the two groups. These findings suggest that there may be comparable levels of lipid peroxidation in children with untreated leukemia and controls, despite the reduced alpha-tocopherol level in leukemic leukocytes.

Spontaneous spinal epidural hematoma (SSEH) has been reported as a rare condition especially in childhood. Because its symptoms are atypical, it is not easy to diagnose the onset of SSEH. However, with wider use of magnetic resonance imaging (MRI), several SSEH cases, especially not requiring surgical intervention, have been reported. We report on a 12-year-old boy who presented with a 5-day history of progressive pain in his back and extremities and numbness of his lower legs. An MRI of the spine demonstrated a dorsal epidural hematoma extending from C4 to T4, and the axial scan of the MRI revealed a posterior hematoma. Neurological deficit was estimated as not severe and not progressive, therefore surgery was postponed, and the patient was discharged without surgical intervention. Seven months later, MRI and myelography were performed, and we confirmed that the spinal epidural hematoma was absorbed. There have been some cases showing spontaneous regression of SSEH, and in younger than 18 years old, most of those cases that were treated with hematopathy such as hemophilia and spontaneous regression after SSEH correlated to larger size of hematoma. Because of bleeding tendencies in these cases the spinal cord was not pressed by the hematoma; this contributed conclusively to the prognosis. On the contrary, the 12-year-old boy, not having bleeding tendency, had the larger lesion of SSEH and recovered spontaneously without surgical intervention. Evaluation of MRI findings and neurological deficits in SSEH cases is important for deciding the indication of surgical intervention.

A tight fixation between bone and implant materials is of great importance for a successful outcome of procedures such as total knee arthroplasty (TKA) and total hip arthroplasty (THA). Surface modification of titanium metal and titanium alloy is one of the attractive methods to improve the biological affinity of orthopedic prostheses. Recent studies reported that titanium substrates were provided with bone-bonding ability, that is, osteoconductivity, through a chemical treatment with hydrogen peroxide solution containing tantalum chloride. The present study investigated the histological and mechanical effects of such treatment of the surface of titanium fiber mesh. Titanium alloy rods of 7.6 × 7.6 × 20 mm that had a titanium fiber mesh of 250 μm were implanted bilaterally into the distal aspect of the femur of adult beagle dogs. At 3, 5, and 8 weeks after implantation, the rods were removed to examine their bonding strength and histological compatibility with bone. Bonding strength was evaluated by the pull-out test. The bonding strength of the treated specimen with bone increased with time, and was faster than that of untreated specimens. At 8 weeks postoperative, the bonding strength of both the treated and untreated specimens became almost equal. The amount of newly formed bone on and in the titanium fiber mesh was significantly increased by the chemical treatment (p < 0.05). The rate of bone formation in the fiber mesh was accelerated after chemical treatment. These results indicated that the surface treatment enhanced bone formation in the initial stage thank to the osteoconductive property of the titanium fiber mesh conferred by the chemical treatment so that faster bonding strength was achieved. Surface treatment providing titanium mesh with osteoconductivity has the advantages of the fast healing and tight bonding for prostheses in TKA and THA. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 64B: 19–26, 2003

Intensive studies on the physics of disruptions and developments of avoidance/mitigation methods of disruption-related phenomena have being carried out in JT-60U. The characteristics of the disruption sequence were well understood from the observation of the relationship between the heat pulse onto divertor plates during thermal quench and the impurity influx into the plasma, which determined the speed of the following current quench. A fast shutdown was first demonstrated by injecting impurity ice pellets to the plasma and intensively reducing the heat flux on first wall. The halo current and its toroidal asymmetry were precisely measured, and the halo current database was made for ITER in a wide parameter range. It was found that TPF x I{sub h}/I{sub p0} was 0.52 at the maximum in a large tokamak like the JT-60U, whereas the higher factor of 0.75 had been observed in medium-sized tokamaks such as Alcator C-Mod and ASDEX-Upgrade. The vertical displacement event (VDE) at the start of the current quench was carefully investigated, and the neutral point where the VDE hardly occurs was discovered. MHD simulations clarified the onset mechanisms of the VDE, in which the eddy current effect of the up-down asymmetric resistive shell was essential. The real-time Z{submore » j} measurement was improved for avoiding VDEs during slow current quench, and plasma-wall interaction was avoided by a well-optimized plasma equilibrium control. Magnetic fluctuations that were spontaneously generated at the disruption and/or enhanced by the externally applied helical field have been shown to avoid the generation of runaway electrons. Numerical analysis clarified an adequate rate of collisionless loss of runaway electrons in turbulent magnetic fields, which was consistent with the avoidance of runaway electron generation by magnetic fluctuations observed in JT-60U. Once generated, runaway electrons were suppressed when the safety factor at the plasma surface was reduced to 3 or 2.« less

Heat and particle control has been studied under the reactor-relevant high-power heating in the large tokamak of JT-60U with an open divertor and progressively a W-shaped pumped divertor. Heat and particle control is crucial for reduction in heat load onto the divertor plates, control of density in the main plasma, effective exhaust of helium ash, and reduction in impurity contamination. For the reduction of heat load, radiative divertor concept was developed based on understanding of heat and particle transport in scrape-off layer and divertor plasmas, which contributed to establishment of divertor concept in ITER. With argon injection, the total radiation loss power reached up to 80% of the net heating power with high confinement of HH{sub y2} {approx} 1, where HH{sub y2} is a confinement enhancement factor over the IPB98(y,2) ELMy H-mode scaling, at high density of 80% of the Greenwald density in the ELMy H-mode plasma. For the density control, the dependence of particle confinement on plasma parameters was systematically studied with two confinement times for center- and edge-fueled particles, which enabled discussion of density controllability. Core fueling using a high-field-side pellet injection extended the operation range of high confinement (HH{sub y2} {approx} 1) from 60 to 70% ofmore » the Greenwald density in the high {beta}{sub p} ELMy H-mode plasma. Efficient helium ash exhaust of {tau}{sub He}*/{tau}{sub E} = 2.8 was demonstrated in the ELMy H-mode plasma with the pumping from the private flux region, which is the same pumping geometry as that in ITER design. Reduction in Z{sub eff} by puff-and-pump scheme was demonstrated, and chemical sputtering yields were estimated with the consideration of not only methane but also heavier hydrocarbons. Their sputtering yields showed strong dependence on the wall temperature and weak dependence on the particle flux. The measured profiles of C II and C IV line intensities were well reproduced by the Monte Carlo impurity transport simulation code (IMPMC code). The estimation of sputtering yields and development of the simulation code enabled reliable predictions for impurity behavior in a fusion reactor.« less

The diagnostic system of JT-60U (JT-60upgrade) is composed of about 50 individual diagnostic devices. Recently, the detailed radial profile measurements of plasma parameters have been improved, so ...

A flat carbon fiber composite (CFC) tile mock-up with screw tubes, which have helical fins like a nut, was fabricated aiming at further improvement of the heat removal performance of the cost-effectively manufactured divert or target for JT-60SC (modified JT-60 as a superconducting coil tokamak). The heat removal performance of the mock-up was successfully demonstrated on the JAERI Electron Beam Irradiation Stand. The estimated heat transfer coefficient of the screw tube at the non-boiling region was roughly three times higher than that of the smooth tube. This corresponds to 1.5 times that of the swirl tube. A heat cycle test of 10 MW/m2 showed that the mock-up with the screw tubes could withstand for 1400-cycles. These results indicate that the divertor target plate with the flat CFC tile and the screw tube can be a promising candidate for the JT-60SC divertor target.

The significance of real-time feedback control is emphasized in this paper as an indispensable method to improve and sustain the improved plasma characteristics in JT-60U high fusion performance discharges as well as to operate the fusion reactor under the optimal divertor conditions with respect to the heat load and exhaust pumping. In accordance, substantial improvement in the equivalent fusion amplification gain of over unity has been reproducibly achieved at the JT-60U tokamak in the reversed shear mode of operation with the robust feedback controls, where the value of target density was deliberately optimized for the reliable internal transport barrier formation, and the magneto-hydrodynamic stability control was performed with the stored energy feedback. The feedback control techniques also demonstrated the effectiveness to produce quasi-steady-state high-performance plasmas. In addition, three major parameters associated with the fusion reactor instrumentations, namely the neutron production rate, operating density, and divertor radiation power, were simultaneously feedback controlled in the ELMy H-mode plasmas. Here, the matrix response function was evaluated to identify the limitations involved with the linear combination of independent controls. Other advanced feedback schemes, such as the feedback suppression of the neoclassical tearing mode required to sustain high plasma pressure in a steady-state, are alsomore » described. Finally, the controversial issues for the future intelligent plasma control necessary for the advanced steady-stated tokamak reactor are addressed.« less

Fusion plasma performance and confinement studies on JT-60 and JT-60U are reviewed. With the main aim of providing a physics basis for ITER and the steady-state tokamak reactors, JT-60/JT-60U has b...

Fast plasma shutdown without runaway electron generation by gas puffing is investigated in the JT-60U tokamak. Argon-only injection enables a fast shutdown; however, it induces runaway electron generation. Hydrogen-only injection generates much less runaway electrons; however, the shutdown time is considerably longer. Mixed injection of hydrogen and argon achieves a fast plasma shutdown without runaway generation. Argon atoms contribute to radiate the energy of plasma leading to a fast plasma shutdown, whilst hydrogen atoms contribute to increase the electron density for avoiding runaway electron generation.

Effect of divertor pumping on the scrape-off layer (SOL) plasma and impurities has been studied in many divertor tokamaks. Recent experimental studies of particle exhaust and SOL flow in JT-60U are reviewed. Pumping flux at the inner and outer pumping slots of the W-shaped divertor was investigated under the attached and detached divertor conditions. The SOL flow pattern was determined, for the first time, at three locations, i.e. at the low-field-side SOL (the outer midplane and divertor X-point) and at the high-field-side SOL (above the inner baffle), using three reciprocating Mach probes. The measured profiles were compared with modelling results from two-dimensional plasma simulations, UEDGE-code, with the ion drift effects included.

JT-60 is planned to be modified to a fully superconducting coil tokamak (JT-60SC) to establish scientific and technological bases for an attractive DEMO reactor. A divertor geometry for JT-60SC is designed to achieve enough exhaust capability for high triangularity configuration, which is essential to obtain high plasma pressure and type II ELMs. For the improvement of detachment control capability, vertical targets are applied with baffle plates into which 3?cm SOL flux surface on the outer midplane can be led. Cryopanels are installed under both a private dome and an outer divertor to allow separated pressure control for inner and outer divertor legs, which is important for the detachment control. The preliminary results of the numerical simulation with SOLDOR/NEUT2D code show that the pumping speed of ?60?m3?s-1 at an outer pumping slot would be enough to control the detachment at the outer divertor without an X-point MARFE under the condition of the edge density of 3.2?1019?m-3 and the SOL power flow of qi = qe = 6?MW.

Objectives: To measure postural changes in cerebral hemodynamics in young patients with chronic fatigue with and without orthostatic intolerance. Study design: We studied 28 patients (age, 10 to 22 years) and 20 healthy control subjects (age, 6 to 27 years). Cerebral oxygenated hemoglobin (oxy-Hb) and deoxygenated Hb were noninvasively and continuously measured with near infrared spectroscopy during active standing. Beat-to-beat arterial pressure was monitored by Finapres. Results: Orthostatic intolerance determined by cardiovascular responses to standing was observed in 16 of 28 patients: instantaneous orthostatic hypotension in 8, delayed orthostatic hypotension in 2, and postural orthostatic tachycardia in 6. A rapid recovery of oxy-Hb by near infrared spectroscopy at the onset of active standing was not found in 15 of 16 patients with chronic fatigue and orthostatic intolerance and in 6 of 12 patients with chronic fatigue without orthostatic intolerance but only in 2 of 20 control subjects. Thirteen of 16 patients with orthostatic intolerance showed prolonged reduction in oxy-Hb during standing. Conclusions: Impaired cerebral hemodynamics in patients with chronic fatigue syndrome and postural orthostatic tachycardia suggest a link between impaired cerebral oxygenation and chronic fatigue. However, this cannot explain the symptoms in patients meeting the criteria of chronic fatigue without orthostatic intolerance. (J Pediatr 2002;140:412-7)