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An intense negative hydrogen ion source has been developed, which has a strong external magnetic filter field in the wide area of 35 cm×62 cm produced by a pair of permanent magnet rows located at 35.4 cm separation. The filter strength is 70 G in the center and the line‐integrated filter strength is 850 G cm, which keeps the low electron temperature in the extraction region. Strong cusp magnetic field, 1.8 kG on the chamber surface, is generated for improvement of the plasma confinement. These resulted in the high arc efficiency at the low operational gas pressure. 16.2 A of H− ion current with the energy of 47 keV was obtained at the arc efficiency of 0.1 A/kW at the gas pressure of 3.8 mTorr in the cesium‐mode operation. The magnetic field in the extraction gap is also strong, 450 G, for the electron suppression. The ratio of the extraction current to the negative ion current was less than 2.2 at the gas pressure of 3 mTorr. The two‐stage acceleration was tested, and 13.6 A of H− ion beam was accelerat...

OBJETIVOS: Comparar custos e benefícios clínicos de três terapias adicionais à metformina (MF) para pacientes com diabetes mellitus tipo 2 (DMT2). MÉTODOS: Um modelo de simulação de eventos discretos foi construído para estimar a relação custo-utilidade (custo por QALY) da saxagliptina como uma terapia adicional à MF comparada à rosiglitazona ou pioglitazona. Um modelo de impacto orçamentário (BIM - Budget Impact Model) foi construído para simular o impacto econômico da adoção de saxagliptina no contexto do Sistema Suplementar de Saúde brasileiro. RESULTADOS: O custo de aquisição da medicação para o grupo de pacientes hipotéticos analisados, para o horizonte temporal de três anos, foi de R$ 10.850.185,00, R$ 14.836.265,00 e R$ 14.679.099,00 para saxagliptina, pioglitazona e rosiglitazona, respectivamente. Saxagliptina exibiu menores custos e maior efetividade em ambas as comparações, com economias projetadas para os três primeiros anos de -R$ 3.874,00 e -R$ 3.996,00, respectivamente. O BIM estimou uma economia cumulativa de R$ 417.958,00 com o reembolso da saxagliptina em três anos a partir da perspectiva de uma operadora de plano de saúde com 1 milhão de vidas cobertas. CONCLUSÃO: Da perspectiva da fonte pagadora privada, a projeção é de que o acréscimo de saxagliptina à MF poupe custos quando comparado ao acréscimo de rosiglitazona ou pioglitazona em pacientes com DMT2 que não atingiram a meta de hemoglobina glicada (HbA1c) com metformina em monoterapia. O BIM, para a inclusão de saxagliptina nas listas de reembolso das operadoras de planos de saúde, indicou uma economia significativa para o horizonte de 3 anos. OBJECTIVES: To compare costs and clinical benefits of three additional therapies to metformin (MF) for patients with diabetes mellitus type 2 (DM2). METHODS: A discrete event simulation model was built to estimate the cost-utility ratio (cost per quality-adjusted life years [QALY]) of saxagliptine as an additional therapy to MF when compared to rosiglitazone or pioglitazone. A budget impact model (BIM) was built to simulate the economic impact of saxagliptine use in the context of the Brazilian private health system. RESULTS: The acquiring medication costs for the hypothetical patient group analyzed in a time frame of three years, were R$ 10,850,185, R$ 14,836,265 and R$ 14,679,099 for saxagliptine, pioglitazone and rosiglitazone, respectively. Saxagliptine showed lower costs and greater effectiveness in both comparisons, with projected savings for the first three years of R$ 3,874 and R$ 3,996, respectively. The BIM estimated cumulative savings of R$ 417,958 with the repayment of saxagliptine in three years from the perspective of a health plan with 1,000,000 covered individuals. CONCLUSION: From the perspective of private paying source, the projection is that adding saxagliptine with MF save costs when compared with the addition of rosiglitazone or pioglitazone in patients with DM2 that have not reached the HbA1c goal with metformin monotherapy. The BIM of including saxagliptine in the reimbursement lists of health plans indicated significant savings on the three-year horizon.

A cesiated hydrogen hollow cathode (CHC) was tested for plasma injection in the multicusp negative ion source (MS). The CHC arc with hydrogen feed and cesium seeding through the CHC volume was explored. One cathode unit (40 mm length, 19 mm in diameter, emission opening area 1–3 mm2) with no special cooling provided the MS discharge operation with direct current up to 30 A, and up to 60 A in the long-pulse mode. High efficiency of negative ion production in the MS discharge, driven by a CHC plasma injection was recorded.

For compensation of the magnetically deflected beamlets, a new type of grid system has been applied to a large negative ion source of a negative-ion-based neutral beam injector in the Large Helical Device (LHD) fusion experimental machine. Corresponding to deviation of the negative ion beamlet trajectory due to the electron suppression magnetic field at the extraction grid, the exit aperture of the extraction grid is displaced to cancel the beamlet deflection by electrostatic lens effect. As a result, the beamlet deflection was suppressed less than 2 mrad in a wide range of energy of 110–180 keV, and the port-through efficiency of the injected beam was improved to 90%–95% from 70%–75% in the case of the previous compensation by the grounded grid aperture displacement. The injected beam power was increased to 3.5 MW with an energy of 165 keV using one injector. To improve beam uniformity of the large area beam, individual arc currents through filaments are controlled for uniform plasma production, with ind...

A millimeter-wave interferometer with the frequency of 39 GHz ({lambda} 7.7 mm) was newly installed to a large-scaled negative ion source. The measurable line-integrated electron density (n{sub e}l) is from 2x10{sup 16} to 7x10{sup 18} m{sup -2}, where n{sub e} and l represent an electron density and the plasma length along the millimeter-wave path, respectively. Our interest in this study is behavior of negative ions and reduction of electron density in the beam extraction region near the plasma grid. The first results show the possibility of the electron density measurement by the millimeter-wave interferometer in this region. The line-averaged electron density increases proportional to the arc power under the condition without cesium seeding. The significant decrease of the electron density and significant increase of the negative ion density were observed just after the cesium seeding. The electron density measured with the interferometer agrees well with that observed with a Langmuir probe. The very high negative ion ratio of n{sub H-}/(n{sub e}+n{sub H-}) = 0.85 was achieved within 400 min. after the cesium seeding.

We describe the characteristic of stable beam injection in a neutral beam injector (NBI) for Large Helical Device (LHD) in high injection power of more than 6 MW. In the NBI, it takes a week after starting Cs seeding to finish the pre‐injection conditioning. The injection starts with the beam power ∼6.2 MW, and the maximum power reaches ∼7 MW. The Cs‐seeding rate affects the beam stability in such high power injections. By optimizing the rate to 0.65 mg/shot, the success ratio, which is defined as a ratio of actual pulse duration to setting one, increases to 85–90% in the power and energy range of more than 6.2 MW and 185 keV, respectively. The weights of Cs adsorbed on several surfaces in the ion sources of the NBI are measured by means of Inductively‐Coupled Plasma Atomic Emission Spectroscopy (ICP‐AES), and averaged surface densities are calculated by dividing with the several surface areas. The seeded Cs of 99.5% is condensed in the plasma generator, and very tiny amount of Cs reaches the surfaces of the accelerator grids. This very low amount of Cs on the grids is interpreted that most of the Cs atom evaporated from the inner walls is ionized during the arc discharges, and repelled to the source plasmas by the electrostatic field for H‐ extraction.

Introdução: Tem crescido nos últimos anos o reconhecimento de que uma avaliação de tecnologias em saúde completa deve incluir não apenas uma análise de custo-efetividade, como também uma análise de impacto no orçamento. Objetivo: Conduziu-se uma análise de impacto no orçamento para avaliar os custos num período de três anos do tratamento de pacientes diagnosticados com leucemia mieloide crônica, após falha ao imatinibe a partir das perspectivas em nível central (Sistema Público de Saúde Brasileiro) e local (Hospital público). Métodos: Desenvolveu-se um modelo de decisão baseado em dados clínicos e epidemiológicos para comparar as opções de tratamento atuais (dasatinibe e imatinibe) reembolsadas pelo governo brasileiro com diferentes cenários que incluem nilotinibe. Resultados: No caso-base, utilizando os preços fábrica oficiais, estima-se que a adição de nilotinibe ao mix tecnológico aumente os gastos totais nos próximos três anos no nível central em até R$ 11.360.282 ou R$ 17.930 por paciente por ano, e no nível central por até R$ 16.437 por paciente por ano. No caso alternativo, baseado nos preços das últimas licitações públicas, espera-se que a adição de nilotinibe ao mix tecnológico aumente os gastos totais nos próximos três anos em até R$ 31.692.792 ou R$ 26.000 por paciente por ano, e no nível local por até R$ 26.600 por paciente por ano. Conclusão: Os resultados dessa análise podem ser utilizados para avaliação da viabilidade financeira nos próximos três anos de tratamentos para diferentes fases de leucemia mieloide crônica em pacientes que são resistentes e/ou intolerantes a imatinibe. Introducción: Ha aumentado el reconocimiento en los últimos años que una evaluación de tecnologías en salud completa debe incluir no solamente un análisis de coste-efectividad, como también un análisis de impacto presupuestario. Objetivo: Se hizo un análisis de impacto presupuestario para evaluar los costos por un período de tres años del tratamiento de pacientes diagnosticados con leucemia mieloide crónica en estos años posterior a falla a imatinibe desde las perspectivas a nivel central (Sistema Público de Salud Brasileño) y local (hospital público). Método: Fue desarrollado un modelo de decisión embasado en datos clínicos y epidemiológicos comparando las opciones de tratamiento actualmente (dasatinibe e imatinibe) reembolsadas por el gobierno Brasileño a diferentes escenarios que incluyen nilotinib. Resultados: En nuestro caso base utilizando los precios farmacéuticos oficiales, se valoró que la adición de nilotinib al mix de tecnologías aumente los gastos totales en los siguientes tres años al nivel central hasta R$11.360.282 o R$17.930 por paciente al año, y al nivel local hasta R$16.437 por paciente al año. En el caso alternativo, embasado en los precios de las últimas licitaciones públicas, se estima que la adición de nilotinib al mix de tecnologías aumente los gastos en los siguientes tres años desde el nivel central hasta R$31.692.792 o R$26.000 por paciente al año, y al nivel local hasta R$26.637 por paciente al año. Conclusión: Los resultados de este análisis pueden ser utilizados para evaluar la viabilidad financiero-económica en los tres años siguientes del tratamiento de pacientes en diferentes fases de leucemia mieloide crónica que están resistentes y/o intolerantes a imatinib. Introduction: In recent years, it has been increasingly recognized that a comprehensive health technology assessment should include not only a cost-effectiveness analysis, but also a budget impact analysis. Objective: A budget impact analysis was conducted to assess the costs of the treatment for patients with chronic myelogenous leukemia within a period of three years after imatinib failure from both central level (Brazilian public health system) and local level (public hospital) perspectives. Methods: A decision model based on clinical and epidemiological data was developed to compare current treatment options (dasatinib and imatinib) reimbursed by the Brazilian government with different scenarios that included nilotinib. Results: In our base case using official pharmaceutical prices, adding nilotinib to the mix of technologies is expected to increase total expenses within the next three years at the central level by up to R$11,360,282 or R$17,930 per patient per year, and at the local level by up to R$16,437 per patient per year. In the alternative case, based on prices from the latest public tenders, adding nilotinib to the mix of technologies is expected to increase total expenses within the next three years at the central level by up to R$31,692,792 or R$26,000 per patient per year, and at the local level by up to R$26,600 per patient per year. Conclusion: Results from this analysis can be used to estimate the affordability for the next three years of treatments for different chronic myelogenous leukemia phases in patients who are resistant to or intolerant of imatinib. &nbsp

An additional beamline, BL5, equipped with four positive ion sources will be installed on Large Helical Device (LHD) in 2010. The performance of an ion source which generates 80 keV deuterium and 60 keV hydrogen beams was investigated. The structure of the ion source is based on that of a BL4 ion source on LHD. The main differences between the ion sources for the BL4 and BL5 are the acceleration voltages and the materials of plasma electrodes: copper and molybdenum, respectively. The molybdenum plasma electrode for BL5 has better performance than the copper plasma electrode of BL4. The integrated performance of the ion source for BL5 reached a value equivalent to approximately 58 A in the beam current of hydrogen positive ion at 60 keV in the beam energy.

A new multi-cusp H− ion source using a localized virtual magnetic filter of type I in the plasma electrode is investigated. A multi-pole arrangement with a spacing of 10 mm of the magnet bars holds an extraction hole, optimizing the efficient production of high H− current, and at the same time only a small electron component was co-extracted with the H− ions. The local filter arrangement separates the beam electrons at a low energy. It is shown that the coextracted total electron current is determined principally by the integrated magnetic field flux (Gcm) of the local filter with an extraction system at a constant extraction voltage. When the value of the Gcm is increased, the total electron component is reduced, while the H− electrical efficiency had a broad maximum around the optimized value of the Gcm. A thicker plasma electrode should be necessary for sufficient reduction of electron current. In pure hydrogen operation, the achieved current density of H− is 10 mA/cm2. When Cs is seeded in a filter op...

Cesium recovery from the polluted layers in the 1/3 scale hydrogen negative ion source for LHD-NBI system has tested. It was found that the cesium recovery can be produced by additional discharges as from the cesium layer, aged by tungsten and residual gas, so as from the cesium layers, polluted by an occasional water leak. The highest cesium recovery to negative ion production was produced by a xenon arc, while glow discharge and arcing in hydrogen were less effective. The mechanism of recovery is the ejection of cesium from the underlying enriched layer by the arc and its transport to the surface.

Negative‐ion‐based neutral beam injection (negative‐NBI) system has been operated for 10 years in Large Helical Device (LHD). The injection power has been increased year by year, according to the improvement of the negative ion sources. Up to now, every injector achieves the designed injection energy and power of 180 keV‐5 MW with hydrogen beams, and the total injection power exceeds 16 MW with three injectors. In the multi‐round aperture grounded grid (GG), the diameter of a round aperture has been enlarged for higher GG transparency. Then, the GG heat load is reduced, as well as in the multi‐slotted GG, and the voltage holding ability in the beam acceleration was improved. As a result, the beam energy is raised and the injection power is increased. To improve the anisotropic property of the beamlet convergence condition between the perpendicular and the parallel directions to the slots in the multi‐slotted GG, a round‐shape aperture of the steering grid (SG) has been changed to a racetrack shape. As a r...

A multi‐antenna radio‐frequency ion source with a Faraday shield is newly tested at a high RF power level in a large area negative ion source of 1/5th scale of the Large Helical Device‐NNBI ion source. Inductively coupled dense hydrogen plasmas were generated uniformly over an area of 25×25 cm2 at an RF input power up to 300 kW for a 10 ms pulse duration. A large negative plasma potential for the non‐Faraday shielded antenna was remarkably reduced by introducing a Faraday shield. The positive ion saturation current density measured by Langmuir probe reached 148 mA/cm2 at 174 kW around the center of the plasma. The optimal hydrogen filling pressure ranged around 0.13 Pa‐ 0.4 Pa for the positive ions. Ion beam extraction with a single hole (φ 0.5 cm) extractor has been studied systematically. A maximum H− ion beam current density of 1.6 mA/cm2 was obtained preliminarily. It was confirmed that the plasma profile was controllable by both the number and configuration of the antennas.

In the large area negative ion source for the LHD negative-ion-(H(-))-based neutral beam system, (I) we used the spectrometer to measure caesium lines in the source plasma during beam shots. (II) With Doppler-shifted measurements, the H(alpha) line at three different locations along the beam as well as the spectrum profile for cases of different plasma grid areas. (III) Caesium deposition monitor with a high speed shutter was tested to measure the weight of the deposited Cs layer. In the observation, cleaner spectra of Doppler-shifted H(alpha) line with only a small level of background light were obtained at a new observation port which viewed the blueshifted light in the drift region after the accelerator of a LHD ion source. Both the amounts of Cs I (852 nm, neutral Cs(0)) and Cs II (522 nm, Cs(+)) in the source plasma light rose sharply when beam acceleration began, and continued rising during a 10 s pulse. It was thought that this was because the cesium was evaporated/sputtered from the source back plate by the back-streaming positive ions. Cs deposition rate to the crystal sensor measured by adjusting the shutter open time was evaluated to be 2.9 nanograms/s cm(2) for preliminary testing. More neutral Cs tended to be evolved in the source after arc discharge. Much Cs could be consumed in a high rate-pulsed operation (such as LHD source).

Large‐scaled hydrogen negative‐ion sources, in which cesium is introduced in the source plasma, have been developed for neutral beam injectors in Large Helical Device, and their operational characteristics are reviewed. For high‐efficient negative ion production, configuration of the magnetic filter field and the cusp magnetic field was optimized, resulting in a high arc efficiency for the negative ion production of 0.23A/kW. With use of a multi‐slotted grounded grid, the gas pressure in the acceleration gap is lowered, leading to reduction of the heat load of the grounded grid. As a result, the voltage holding ability is much improved, and the rated energy of 180 keV is achieved in a short conditioning period of 4 days. The injection power is increased linearly to the 5/2 power of the beam energy and reached 5.7MW with an energy of 184keV, which exceeds the specified value of 180keV–5MW. Beam uniformity has been improved with an individual control of the local arc discharge by adjusting 12‐divided output...

Two large helical device–neutral beam injector (LHD–NBI) ion sources were fabricated and tested in the test stand for producing a beam of 180 keV×40 A with H− ions. They are Cesiated multicusp ion sources with a rectangular discharge chamber and a single stage multihole accelerator. These are scaled up from the 16 A H− ion sources in the National Institute for Fusion Science (NIFS). A plasma source with a high aspect ratio was operated stably with an arc power up to ∼300 kW for 10 s, after balancing of the electron emission from the filaments was made. A satisfactorily dense and uniform plasma without mode flip was produced. Electrons accompanied by H− ions were reduced by an extraction grid with the electron trap, instead of straight holes. The electron beam component caused by the stripping of electrons from H− ions was detected with an array of calorimeters at the bottom of the connecting duct. At the first stage of the test, one of the five segment grids of the accelerator was installed. An H− ion cur...

A large hydrogen negative-ion source was constructed as a prototype one for the negative-ion-based neutral beam injection (NBI) system in large helical device. The ion source is designed to produce 180 keV-40 A of the negative ion beam with a current density of 40 mA/cm2, and is a cesium-seeded volume production source characterized by the external magnetic filter. The arc chamber of multicusp bucket is rectangular of 35 cm×145 cm in cross section and 21 cm in depth. The accelerator is a three-grid single-stage one, and the total grid area is 25 cm×125 cm, which is divided into five sections. The ion source was installed on the negative-ion-based NBI test-stand, and using one section of the grid 5.5 A of the negative-ion beam was produced at a gas pressure of 1.8 mTorr corresponding to a current density of 27.5 mA/cm2. The extracted electron current is low of 50% of the negative ion current, and the acceleration efficiency, defined as the negative ion current divided by the acceleration drain current, is ...

Compact cesiated hollow cathodes (CHC) has been developed and studied in two large multicusp H− ion sources at NIFS, aiming the long lifetime cathodes for plasma production in the neutral beam injectors. Results on hollow cathodes and power supplies improvement are described. Basic characteristics of multicusp source discharge, driven by several CHCs were studied. Key issues about simultaneous CHCs operation in high current discharge mode are discussed. Each of advanced CHC delivered stable and quiet income with current up to 70A for 5sec to multicusp source discharge. The hollow cathode operation with no Cs feed was obtained by using 30%Xe+70%H2 gas mixture.

The new beam accelerator with multi‐slot grounded grid (MSGG) has been developed to increase the port‐through power into large helical device (LHD). Using the accelerator, the maximum power of 5.7 MW was achieved at the beam energy of 186 keV in the beam injection to LHD plasma last year. Although the port‐through power increased compared with conventional accelerators with multi‐hole grounded grid (MHGG), the accelerator with the MSGG includes a disadvantage of bi‐focal condition in parallel and perpendicular direction to the long side of the slots. When the beam width in one of those directions gets narrower, the width in another direction becomes wider. This disadvantage includes the loss of beam port‐through power and induces internal damages in neutral beam line. In order to reduce the disadvantage, an experiment has been done using a small‐scaled negative ion source with racetrack‐shaped apertures for the steering grid installed at beam upstream of the MSGG. By applying the racetrack apertures to the accelerator, it is observed that the beam widths in the parallel and perpendicular directions to the slot long side have almost the same focal condition to obtain minimal beam widths.

MethOdS: The Orizon database, an administrative database containing inpatient and outpatient claims to a pool of 102 HMOs representing 34% of the total Private Health System, was reviewed from Jan/2009 to Dec/2012. Eligibility criteria were patients starting CLL (ICD-10 code C911) treatment from Apr/2009 to Dec/2011. Outcome was direct medical costs (DMC) per patient-year, calculated as the sum of the medical claims for each patient included in the analysis, for a maximum period of 12-months or death or loss of follow-up, whichever comes first. DMC was categorized in chemotherapy, hospitalizations, and other outpatient costs. Further analysis was conducted for chemotherapy and hospitalizations.

A large vacuum‐immersed H− ion source has been operated on the negative‐ion‐based neutral beam teststand. The achieved level of the beam and the pulse duration in beam conditioning were limited by a high‐voltage breakdown in the vacuum vessel. A baffle plate at grounded potential for shielding completely from the charged particles was successful. A beam with an energy of up to 102 keV and the H− ion current of 0.55 A were achieved for 0.29 s without the breakdown. The ion current of ∼1.5 A was accelerated in cesium‐seeded operation. The corresponding ion current density was ∼7 mA/cm2. A magnetic filter (as Type I LV magnetic filter) on the plasma electrode was applied. The electron beam component which was extracted from the plasma source together with H− ions was found to be very reduced.

A large hydrogen negative‐ion source with an external magnetic filter has been developed for a neutral beam injection (NBI) system in the Large Helical Device (LHD), and a high‐energy and high‐current H− ion beam has been produced. The ion source is operated at a high arc efficiency of 0.1 A/kW at an operational gas pressure of less than 3.5 mTorr, and produces 47 keV–16.2 A of a H− ion beam from a grid area of 25 cm×50 cm. With two‐stage acceleration, 13.6 A of a H− ion beam has been successfully accelerated to 125 keV. Multibeamlet focusing by the aperture displacement technique has been achieved 11.2 m downstream with a gross divergence angle of 9 mrad. The alternate beamlet deflection by the magnetic field at the extraction grid, which results in beam broadening in the deflection direction, was well compensated also by the aperture displacement technique. These results satisfy the specification of the negative‐ion‐based LHD–NBI system.

Failures of flexible pavements (bituminous roads) have been prevalent in many developing countries, a trend causing concern to both the road users and the roads authorities. In this regard, it was found necessary that an investigation be initiated to determine the possible causes of such failures, and a case study was carried out on Nairobi-Thika Highway in Kenya. The investigations were conducted in several categories to determine the pavement characteristics such as structural strength by Benkelman Beam Deflection Test (BBDT), skid resistance by British Pendulum Tester (BPT). Traffic loading by Axle load measurements, Traffic volumes by traffic counting and ageing characteristics of the type of the bitumen used by cutting cores and extracting the bitumen for the standard tests, such as penetration, ductility, bitumen content, air voids, softening point and CBR using the Light Drop Weight Tester (LDWT). The visual inspection of the pavement showed that due to the hardening of the bitumen and overloading, cracks and potholes were very common for the whole stretch of the road. Axle load data revealed that, there has been a tendency to exceed the maximum allowed axle load limits, especially until 19th august, 1999, after that the enforcement of axle load limits was tightened. This fact together with the revelation that the road is a very busy one as depicted in the traffic counts, could be one of the major causes of the road's fast deterioration. (Journal of Civil Engineering, JKUAT: 2002 7: 13-26)

Atomic resolution low-angle bright-field (LABF) scanning transmission electron-microscope (STEM) images and high-angle bright-field (HABF) STEM images of [011]-orientated Si have been experimentally obtained together with high-angle annular dark-field (HAADF) STEM images. The contrast formation mechanisms of the LABF STEM and HABF STEM images are examined in comparison with HAADF STEM images. The HABF STEM images independent of defocus and thickness have spatial resolution comparable with HAADF STEM images, and are shown to be given as a simple convolution under the non-dispersion approximation of localized Bloch waves.

Large current negative hydrogen ions are extracted from a multicusp ion source with an extraction area of 25×44 cm2. By seeding a small amount of cesium vapor into a source chamber, the H− current is enhanced to several times larger than that in a pure hydrogen discharge, accompanied by a reduction of the electron current and the filling gas pressure. A H− current up to 16 A is obtained with a beam energy of 40 keV from 560 extraction holes of 9 mm in diameter each, where the current density is 45 mA/cm2. The H− current increases linearly with the input arc power.

Summary form only given. Magnetic multicusp ion sources, also known as bucket-type sources, are suitable for producing large-area ion beams and they have been developed as high-current ion sources in neutral beam injector (NBI) systems for nuclear fusion plasma heating. Neutral beams are produced by neutralization of ion beams in the systems. Recently, development of a negative-ion-based NBI system has become desirable for higher energy neutral beam production. The neutralization efficiency of a positive ion beam decreases as beam energy rises (20% at 100 keV, 15 A: 1/3 current of LHD ion source) was a condition of the design. The bucket plasma source has a 35 cm/spl times/62 cm area and a 20.6 cm depth. A large-area high-density plasma (>10/sup 12//cm/sup 3/) is produced by a high power are discharge (>100 kW) with tungsten filaments. For H/sup -/ production, a magnetic filter is used to lower the electron temperature of the negative ion production region near the beam extraction grid.

A high-power negative-ion-based NBI system is now under construction for Large Helical Device (LHD). The neutral beam injection power and energy are designed to be 15 MW and 180 keV, respectively, for hydrogen, and the pulse duration is 10 sec. Two beamlines are installed to LHD, the injection direction of which is tangential and balanced with each other. Two large negative-ion sources are attached side-by-side to each beamline, which produce 180 keV-40 A of the negative ion beam. The prototype ion source has just started operation in the negative NBI test stand, and produced 106 keV-21 A of the negative ion beam. The fabrication of the beamline components and the power supplies have been almost finished. The installation to LHD starts in October and is completed in March, 1998. After the commissioning and the conditioning, the injection to LHD is scheduled in September, 1998.

Development of the control and communication system for the plasma heating unit of Large Helical Device (LHD: an experimental machine for fusion science) has been continued. The system is composed of a distributed and concurrent client/server system by the use of several UNIX workstations, and its sub-systems are controlled by PLC (Programmable Logic Controller), VME (Versa Module Europe). Almost all of its control system are connected via Ethernet with IEEE802.3. Man-machine interface system and hardware/software of the control system have been completed.

The dysembryoplastic neuroepithelial tumor (DNT), characterized by its favorable prognosis, must be precisely differentiated from other gliomas to prevent overtreatment by radio/chemotherapy. We studied, here, pathological features of five surgical cases of DNT with intractable epilepsies. There were two males and three females with a median age of 20.4 years (range 12-41). We evaluated lesional topography, gross appearances and microscopic findings including immunohistochemical data. One tumor was located in the temporal lobe, another two in the parietal lobe, another in the occipital lobe, and the other one in the occipito-parietal junction. The lesions were predominantly intracortical in all cases. Macroscopically, two tumors were grayish-soft, another two were yellowish-elastic, and the other one was resected as soft-mucinous fragments. Microscopically, the main glial components were oligodendrocyte-like cells (OLCs) in all cases, except for one case in which atypical glial cells were also prominent. Histopathological characteristics of the DNTs included the specific glioneuronal elements (the mixture of OLCs and neurons) in four cases, alveolar pattern (all cases), microcystic degeneration (all cases), multinodular architecture (four cases), and adjacent cortical dysplasia (all cases). Immunohistochemically, Ki-67 labelling indices ranged from 0 to 0.8%. OLCs were positive for glial fibrillary acidic protein in two cases, for S-100 protein in all cases, for synaptophysin in two cases, and for class III beta tubulin in all cases. Pathological features of our cases were characterized by its heterogeneous histological appearances and divergent cellular differentiation.

In this paper we report the first results on a prototype negative ion source for LHD-NBI. The ion source with a multi-cusp configuration consists of the external magnetic filter and has an inner volume of 140 cm in height ×35 cm in width ×25 cm in depth. Two cesium lines are installed to seed cesium vapor into arc plasma for enhancement of H− current. The H− ion beam was extracted from an area of 120 cm×25 cm and was accelerated via single-stage accelerator. An H− current of about 4 A with the energy of 73 keV was obtained at the arc power of 250 kW for a duration of 0.3 sec.

The efficacy of combined hepatic arterial infusion chemotherapy and hyperthermia for unresectable hepatic tumors of colorectal cancer was retrospectively compared with hepatic arterial infusion chemotherapy alone. Nine cases were treated with combination therapy and eight cases were treated with hepatic arterial infusion alone. The response rate in the combined hepatic arterial infusion/hyperthermia group was higher (44% v 25%) and the survival period longer (2-year survival, 35% v 12%) than in the group treated with hepatic arterial infusion alone. The toxicity was not severe, with the exception of gastrointestinal symptoms, suggesting that this combination of modalities is useful in the treatment of metastatic liver tumors.