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Stokes parameters have been measured by using a polarimeter consisting of a rotating phase plate before a fixed polarizer for bullet-shaped red, green and blue LEDs at 3 different directions of 0°, 45° and 90° from the principal axis. The degree of polarization is minimum at the observation angle 0° (observed head-on) for all colors as expected but has non-zero values (1-9%). As for the possible cause for the partial polarization, it is likely to be brought by striae inside the transparent epoxy resin that can be easily visible. Data at observation angle 90° have features common for all colors; the degree of polarization is highest, the long axis azimuth of the polarization ellipse is nearly in the horizontal direction, and the ellipticity is small. These features can be explained as follows. At observation angle 90°, only small fraction of the beam emitted nearly horizontally is detected possibly through multireflection (the plane of incidence is in the vertical plane) inside the top- and bottom-surfaces (in the horizontal direction) of the chip substrate. Since the reflectance for s-polarization (horizontal component) is higher than that for p-polarization, the emerging beam becomes horizontally polarized. The hypotheses that geometrical asymmetry generates polarization is experimentally supported.

Disassembly of the JT-60U torus was started in 2009 after 18 years of D2 operations and was completed in October 2012 for assembling the JT-60SA torus at the same position. The JT-60U torus was featured by the complicated and welded structure against the strong electromagnetic force, and by the radioactivation due to deuterium–deuterium (D–D) reactions. Since this work is the first experience of disassembling a large radioactivated fusion device in Japan, careful preparations of disassembly activities, including treatment of the radioactivated materials and safety work, have been made. During the disassembly period over 3 years, careful measures against exposure were taken and stringent control of exposure dose were implemented, and as a result, accumulated collective effective dose of ∼41,000 person-day to workers was only ∼22 mSv in total and no internal exposure was observed. About 13,000 components cut into pieces with measuring the contact dose were removed from the torus hall and stored safely in storage facilities. The total weight of the disassembly components reached up to ∼5400 tonnes. Most of the disassembly components will be treated as non-radioactive ones after the clearance level inspection under the Japanese regulations in the future. The assembly of JT-60SA has started in January 2013 after this disassembly of JT-60U torus.

On JT-60U, two mass data acquisition systems have been acquiring 91 channels of fast-sampling diagnostic data. They are, however, based on rather outdated bus standards and now difficult to update. Therefore we have developed a new mass data acquisition system that has more flexibility and ability to perform a faster data acquisition based on a modern bus standard. The system consists of PXI-based (PCI extensions for instrumentation) digitizers connected to controller PCs, and a server for collecting and processing data from these PCs and transferring them to the main diagnostic computer. Up to now, we have verified that the system acquires 27 channels of data that amounts to 2.2 GB in total, from 3 controller PCs, at a sampling rate of 1 MS/s in a 45 s discharge.

The design activity of JT-60SA (JT-60 Super Advanced) addresses the remodeling of JT-60 to a superconducting tokamak device under the JA-EU collaborative ITER–BA project. For the JT-60SA control system, the existing system should be reused as much as possible from the viewpoint of cost-effectiveness. Initial considerations of the configuration of the advanced supervisory control system (SVCS) including the following systems are: (1) an ultimate flexibility real-time control system, (2) a precision timing system able to diagnose a plasma event having a time range of ∼1 μs, and (3) a safety shutdown control system. In this report, we present the design study of the JT-60SA SVCS with the focus on the above systems.

In JT-60U, a mainframe computer called inter-shot processor (MSP-ISP) had been supervising the data acquisition of diagnostic subsystems, managing the storage of obtained data, and establishing communication with the JT-60U's discharge control system. But due to the increased demand for advanced diagnostics, such as improving spatial and temporal resolutions or extending the data acquisition period, the old ISP had been becoming insufficient in power and less cost effective. To resolve this problem, we have gradually migrated ISP to a new UNIX server (UNIX-ISP), and thereby carried out the decentralization of the old ISP's functionalities. Also we are developing a new mass data acquisition system (MDAS) that has simple architecture but has greater performance and flexibility. Simultaneously, to handle the increased volume of data, we are renewing the data storage system. The renewed data processing system (DPS) is now in operation. The performance of the new ISP and the newly developed MDAS is presented.

JT-60 data processing system (DPS) possesses three-level hierarchy. At the top level of hierarchy is JT-60 inter-shot processor (MSP-ISP), which is a mainframe computer, provides communication with the JT-60 supervisory control system and supervises the internal communication inside the DPS. The middle level of hierarchy has minicomputers and the bottom level of hierarchy has individual diagnostic subsystems, which consist of the CAMAC and VME modules. To meet the demand for advanced diagnostics, the DPS has been progressed in stages from a three-level hierarchy system, which was dependent on the processing power of the MSP-ISP, to a two-level hierarchy system, which is decentralized data processing system (New-DPS) by utilizing the UNIX-based workstations and network technology. At present, replacing the MSP-ISP with a UNIX-based workstation is under way as a final phase in building the New-DPS project. This replacement will be accomplished by October 2005. In addition, remote experiment in JT-60 is considered to be an important issue in extension of the collaborative research among the nuclear fusion community. Technical environments for this task have been developed. The participant from a remote site can set discharge parameters with assistance of the dedicated machine operating status-information tools.

The large tokamak fusion device JT-60 is expected to explore more advanced tokamak discharge scenarios toward the ITER and a future power reactor. Since various experimental issues are to be adequately discussed, and possibly to be solved in JT-60, the plasma real-time control system has been drastically improved with remodelling in hardware as well as in software. To satisfy the requirements, a “multiple networks” structure is employed as a basic principle of the remodelling. Distributed processors for diagnostics, actuators, and supervisory controllers are linked through a reflective memory (RM) network for fast, real-time communication. Similarly, advanced and complex calculations to reproduce plasma shape and profiles are performed by several processors connected to the same RM network. In this report, we discuss the developments to improve the JT-60 plasma control and data processing systems. In addition, a future plasma control system leading to a standard design for a power reactor is outlined, which is based on the 20-year plasma operation experience.

JT-60U's diagnostic systems have been using CAMAC systems for their control and data acquisition. But the transient recorders used to store the diagnostic data are rather old and lack in memory expansion. Therefore, for a long pulse discharge of more than 15 s, data sampling rate must be reduced to cover the whole discharge period. The acquired data has, however, low time resolution and is sometimes insufficient for detailed analysis. To solve this problem, the transient recorders should be replaced with those having larger memory, but without modification to the existing data processing infrastructure. For this purpose, we have developed a new data acquisition system with SPARC CPU on VMEbus and the associated software, to retain the functionality of CAMAC control. We have applied this system to the existing bolometric diagnostics. In this paper, detail of design will be described.

A mock-up module of an antenna tip made of carbon fiber composite (CFC) was fabricated for the development of a heat-resistive front of the lower hybrid current drive (LHCD) antenna. The CFC surface was coated with a thin Ti layer and was plated with Cu. The mock-up module has three waveguides and is designed to simulate the front tip of the 8 GHz LHCD antenna. The module has an active water cooling channel and the length is 200 mm, the mouth dimension is 19.5×50 mm 2 . The mock-up module was tested with heat fluxes up to 20 MW m −2 due to electron beam irradiation. No damage of the waveguide mouth was observed up to the heat flux of 3.2 MW m −2 for 2 min, though a maximum temperature of 762°C was measured at the septum plate. The obtained heat load of 3.2 MW m −2 is about 10 times higher than the steady-state surface-averaged heat load of the first wall required in the ITER design.

Fusion performance of reversed shear discharges with an {ital L}-mode edge has been significantly improved in a thermonuclear dominant regime with up to 2.8 MA of plasma current in the JT-60U tokamak. The core plasma energy is efficiently confined due to the existence of persistent internal transport barriers formed for both ions and electrons at a large minor radius of r/a{approximately}0.7 near the boundary of the reversed shear region. In an assumed deuterium-tritium fuel, the peak fusion amplification factor defined for transient conditions involving the dW/dt term would be in excess of unity. {copyright} {ital 1997} {ital The American Physical Society}

Purpose: To compare the performance of various types of unsharp mask filter applied in storage-phosphor-based computed radiography (SR), and to improve the detection of faint nodules of the lung cancer type. Material and Methods: A total of 120 SR radiographs were obtained by means of an anthropomorphous chest phantom and a combination of 3 types of small simulated nodule (5-mm sphere-shaped, and 5-mm and 10-mm hemisphere-shaped) placed on the phantom's surface. Eight combinations of nodule site were selected from 16 predetermined chosen sites, and 5 types of parameter were used for unsharp mask filtering. Eight observers evaluated the images, and the detectability of the lung nodules was evaluated from the images by a ROC analysis. Results: The visibility of the 10-mm hemispherical nodules was nearly equivalent at each site when 5 types of unsharp mask filter were used. The detection of the 5-mm nodules with mid-frequency suppressing and very-low-frequency enhancing filters was better than with a conventional (department standard) mid-frequency enhancing filter. Conclusion: Mid-frequency suppressing versions of the filter helped to demonstrate faint nodular opacity, which is often shown by early bronchogenic carcinoma. This filter could replace conventional filters in the detection of lung nodules.

「目的」成人病を合併した中高年齢患者は, 強力な化学療法に耐えられないことが多い。これに対処し得る適切な放射線療法と化学療法の併用療法を検討した。「対象方法」1984年1月から1993年12月までの間に初回治療を行ったワルダイヤ輪初発非ホジキンリンパ腫びまん性中等度悪性群 Stage IE IIEで成人病を合併した38例を対象とした。投薬量を70%に減量したACOP (2 cycle) もしくはMACOP-B (8 weeks) を行った後, 30Gyの隣接リンパ節領域照射と10～20Gyの局所追加照射の併用療法で治療した。「結果」5年局所制御率は100%であり, 5年非再燃および5年疾患特異性生存率は, 85.7%と91.4%であった。治療完遂率は100%であり, 併用療法による重篤な合併症を認めなかった。「結語」ワルダイヤ輪初発の成人病を合併した中等度悪性群に対しては, 70%に減量した短期間の化学療法と, 病巣部位に対する40Gyの局所照射および30Gyの隣接リンパ節領域照射の併用療法が, 有用であり安全であった。

To investigate the value of magnetic resonance imaging (MRI) in determining the parent nerves of neurogenic tumors in the thoracic inlet, analysis of MR images was performed in nine patients with surgically resected neurogenic tumors in the thoracic inlet (two neurofibromas and one schwannoma of the vagus nerve, three schwannomas of the brachial plexus, and two schwannomas and one ganglioneuroma of the sympathetic nerves). These MR images were compared with surgical and pathologic findings. The multidirectional capability and excellent tissue contrast of MRI facilitated recognition of the location, shape, and extent of the tumors. MRI, which permitted an easy understanding of the spatial relation between the tumors and the subclavian vessels, scalenus muscles, and brachial plexus, was useful in determining the nerves of origin. Two neurofibromas, four of six schwannomas, and one ganglioneuroma were recognized to extend along the axes of the parent nerves on MR images. MRI is useful in determining the parent nerve of neurogenic tumors in the thoracic inlet and is helpful in planning surgical treatment of these tumors.

${\mathrm{Sr}}_{2}$${\mathrm{IrO}}_{4}$ and ${\mathrm{Sr}}_{2}$${\mathrm{RuO}}_{4}$ are both ${\mathrm{K}}_{2}$${\mathrm{NiF}}_{4}$-structure oxides. ${\mathrm{Sr}}_{2}$${\mathrm{IrO}}_{4}$ is a weakly ferromagnetic insulator and ${\mathrm{Sr}}_{2}$${\mathrm{RuO}}_{4}$ a paramagnetic metal. The ${\mathrm{Sr}}_{2}$${\mathrm{Ir}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Ru}}_{\mathit{x}}$${\mathrm{O}}_{4}$ solid solution displays surprising physical properties. On the substitution of Ru to ${\mathrm{Sr}}_{2}$${\mathrm{IrO}}_{4}$, the Ru first exhibits its expected S=1 local magnetic moment, but at a critical Ru concentration of x\ensuremath{\simeq}0.7 the local moment disappears, the apparent density of states at ${\mathit{E}}_{\mathit{F}}$ increases, and an insulator-to-metal transition occurs. These changes in physical properties are accompanied by a change in the crystallographic cell parameters.

Preoperative ultrasonograms of 11 surgically proved thymomas and ex vivo ultrasonograms of 3 resected specimens were compared with pathologic findings of resected specimens. Among 11 thymomas 7 appeared solid, 3 were solid with several cystic regions, and the remaining one was unilocular cystic in appearance. Cystic regions on ultrasonograms corresponded to cystic changes on pathologic specimens. Six malignant thymomas showed a typical lacy appearance on ultrasonograms, which corresponded to the lobulated configuration separated by fibrous septa shown on the pathologic specimens.

An MR-pathologic correlation of nine intrathoracic neurogenic tumors (three neurofibromas, four schwannomas, and two ganglioneuromas) was performed to characterize their MR appearances. The three types of intrathoracic neurogenic tumor were found to have characteristic appearances on MR images that should be helpful when establishing the differential diagnosis of posterior mediastinal tumors. The MR and histologic features of these tumors are illustrated and described in this essay.

Plasma coupling tests of the RF heating system in JT-60 were successfully performed at JAERI prior to the substantial injection for the plasma heating experiment. About 24 MW LHRF at 2 GHz band and 6 MW ICRF at 120 MHz band system were installed in JT-60. The total system is remotely controlled via a mini-computer, which is linked with the central control system named “ZENKEI” and “CAMAC” systems. The RF power and phase difference can be controlled according to a set preprogram and the plant data can be collected and recorded during RF injection. These are carried out at both LHRF and ICRF injections and simultaneous NBI injection. It is shown that this RF heating system can contribute to both LHRF and ICRF heating experiments for JT-60.

14年間の透析歴をもつ患者に発生した肺の扁平上皮癌に高度の石灰沈着が認められた.従来の報告では稀なX線所見と思われるので, そのX線像を中心に報告した.術前の高分解能CT像では腫瘍全般に石灰化像が認められ, 腫瘍中心部では殊に密な石灰化像が認められた.摘出肺の伸展固定標本のCT像および軟X線像でもこれが再現された.術前の骨シンチグラムでは, 腫瘍への集積像および腫瘍以外の肺野においてもびまん性の集積像が認められた.典型的な高カルシウム血症や副甲状腺機能亢進症は証明されなかったが, 本例の腫瘍への高度の石灰沈着, 並びに肺へのびまん性石灰沈着は慢性腎不全と長期の透析に伴う転移性石灰沈着と考えなければ説明できないと思われた.今後長期透析症例の増加に伴って類似例が増加する可能性があり, 腫瘍内での石灰化像の存在を肺癌と良性腫瘤の鑑別点とする従来のX線診断基準の適用に際して留意すべき事項と考える.

The JT-60 LHRF launcher was designed with broad frequency capability (1.74 to 2.23 GHz) to inject multi-megawatt, multi-second RF waves into plasmas. The launcher is characterized by 32 long vacuum waveguides of ∼ 8 m without front windows to avoid plasma bombardment of the ceramic windows in the large tokamak. The front of the launcher is of a detachable grill so it can be changed easily to optimize the wave spectrum. Three types of grills have been developed, and one of them employs a multijunction technique to drive the plasma current efficiently. Three launchers have been installed on JT-60, and the total injection power has reached up to ∼ 10 MW. A good coupling of reflection coefficients, ∼20%, has been obtained for yarious plasma configurations. The development and operation of the LHRF launcher on JT-60 are described.

The JT-60 LHRF heating system was designed with broad frequency capability to inject a long-pulse-width high-power RF wave into a plasma. The system uses 24 high-power klystrons, each with an output power rating of 1 MW. Five operating frequencies are available within the range of 1.74 GHz to 2.23 GHz. The frequency can be changed at a rate of 150 MHz/0.3 s. This feature provides both plasma heating and plasma current drive. It also permits frequency correlation with the plasma density and current profile. This paper describes both the high-speed frequency tuning system for the JT-60 klystrons and the results of fast frequency change tests of the LHRF over the range of 1.74 GHz to 2 GHz when RF power was launched from the same launcher during a plasma shot.

Recent lower hybrid current drive (LHCD), and heating (LHH) experiments on JT-60 are reported. The current drive product of neRpIRF approximately 12.5*1019 m-2 MA was achieved at the LH power of approximately 4.5 MW, and the CD efficiency, the energy confinement, the global power balance and the heat load on divertor plates were investigated in high power LHCD plasmas. Nearly steady state H-mode discharges were found during LHCD with two different frequency injections. Sawtooth suppression in NB heated plasmas by LHCD have shown an improvement in confinement near the plasma center. Parametric instabilities in LH heating experiments were significantly reduced by increasing the plasma current, and the stored energy increased linearly with heating power of up to approximately 9 MW at ne approximately 7*1019 m-3 and Ip=2.75 MA. Parametric instabilities near the plasma edge in the ion heating regime were also reduced in peaked density plasmas produced by pellet injection and LH waves increased the central plasma pressure at ne(0) > 1.4*1020 m-3.

The degradation mechanism of 0.15 /spl mu/m GaAs PHEMTs subjected to three-temperature elevated lifetest (T/sub 1/=185/spl deg/C, T/sub 2/=200/spl deg/C, and T/sub 3/=215/spl deg/C ambient temperatures in N/sub 2/ atmosphere and stressed at Vds=5V/Ids=250 mA/mm) under RF-overdrive at 20 GHz was investigated. The results show that Pout degradation is due to Ids degradation induced by Ti gate metal interdiffusion into the AlGaAs Schottky barrier layer. However, /spl Delta/Imax, /spl Delta/Gmp, and Ti interdiffusion depth depend on the RF-drive levels. Accordingly, a distinct difference of reliability performance between DC (no RF-overdrive) and RF-overdrive lifetests was demonstrated. It has been found that both DC and RF-overdrive lifetests exhibit similar activation energy, which is approximately 1.65 eV. However, the mean-time-to-failure (MTTF) of RF-overdrive lifetest is inferior to that of DC lifetest. The difference is attributed to the higher electric field present in the RF-overdriven lifetest.

We propose new test device structures, gate-last-formed structures, which are suitable for fundamental study of high-k gate insulator or metal gate electrode MISFETs. The gate insulator and electrode are formed after local interconnect pads connected with source and drain. The gate electrode is formed in a trench by dry and wet etching techniques and is non-self-aligned to the source and drain. The wet etching restricts damage formation on the exposed Si surface underneath the trench. This structure can provide methods both for fundamental evaluation and for material selection of new gate stack materials by investigation of MISFET characteristics. This is achieved with short TAT and avoiding contamination penalty to a fab.

This paper describes the fabrication process and the performance of 65 nm-node CMOS transistors which have ultra-shallow junctions. Flash lamp annealing enhances the drivability of pFETs with a solid phase epitaxial extension junction. The increase in the junction leakage of the extension junction is less than 1 order of magnitude as compared with that for the conventional spike RTA on a 300 mm/spl phi/ wafer. Excellent Vth control at 35 nm gate length without halo implantation and a high switching speed at 0.9 V power supply are demonstrated for 65 nm-node LOP (low operation power) applications.

Purpose: To compare the effect of compression of spiral low-dose CT images by the Joint Photographic Experts Group (JPEG) and wavelet algorithms on detection of small lung cancers. Material and Methods: Low-dose spiral CT images of 104 individuals (52 with peripheral lung cancers smaller than 20 mm and 52 control subjects) were used. The original images were compressed using JPEG or wavelet algorithms at a ratio of 10:1 or 20:1. Five radiologists interpreted these images and evaluated the image quality on a high-resolution CRT monitor. Observer performance was studied by receiver operating characteristic (ROC) analysis. Results: There was no significant difference in the detection of cancers measuring 6 to 15 mm in uncompressed images and in those compressed by either of the algorithms, although the quality of images compressed at 20:1 with the wavelet algorithm was somewhat inferior. A lower diagnostic accuracy was noted using images compressed by the JPEG or wavelet algorithms at 20:1 in detecting lung cancers measuring 6 to 10 mm and cancers measuring from 6 to 15 mm with ground-glass opacity. Conclusion: Compression of low-dose CT images at a ratio of 10:1 using JPEG and wavelet algorithms does not compromise the detection rate of small lung cancers.

Purpose: To determine the optimal tube current for spiral CT for lung cancer screening. Material and Methods: Low-dose spiral CT images from 20 subjects were obtained with 50 mA, 25 mA, 10 mA and 5 mA tube currents. The accuracy in detecting 21 nodules measuring 3 to 14 mm in diameter was tested using receiver operating characteristics (ROC) to determine the diagnostic accuracy and statistical significance. Results: Compared with 50 mA, 25 mA showed no statistical difference. A significant difference was seen between 50 mA and 5 mA images and between 25 mA and 10 mA images, in the detection of lung parenchymal nodular lesions. Conclusion: Approximately 25 mA is the optimal tube current for the detection of pulmonary nodules as it allows a reduction of the radiation dose without sacrificing diagnostic accuracy.

(1990). Treatment of Early Vocal Cord Carcinoma with 60CO Gamma Rays, 8/10 MV X-Rays, or 4 MV X-Rays—are the Results Different? Acta Oncologica: Vol. 29, No. 5, pp. 637-639.

Purpose: To present 23 patients ≥ 90 years old treated with radiotherapy, and to retrospectively evaluate the results of radiotherapy and tolerance in these patients. Methods and Materials: The clinical records of 27 patients over 90 years of age who were treated with radiotherapy at the Department of Radiology, Shinshu University Hospital, and eight affiliated general hospitals from 1990 until 1995 were reviewed. The strategy of radiotherapy was individually planned depending on the stage of the disease and performance status (PS) of the patient; however, it was not modified, based solely on chronologic age. The overall survival rate and disease-free survival rate were determined using the Kaplan–Meier method. The Radiation Therapy Oncology Group scoring criteria of acute and late reactions of radiation therapy were used. Results: This group of patients accounted for 0.37% of all patients treated with radiotherapy in these hospitals. Of these, 23 patients in whom cancer was pathologically confirmed and whose follow-up data were available for retrospective analysis were included in the final evaluation of data. The age of the 23 patients ranged from 90 to 96 years (median 93). Tumor was untreated and in the early stage in five patients, locoregionally advanced in 13, recurrent in four, and systemic in one. Definitive radiation therapy was administered in 12 patients (13 sites), preoperative intent in one, and palliative intent in 10. The period of observation ranged from 2.5 to 6 years (median 18 months). Seven patients were alive for 15–67 months. Fourteen patients died because of intercurrent diseases or senility associated with active cancer, and two because of senility without evidence of cancer. The overall and relapse-free survival rates were 65% and 30% at 1 year and 30% and 21% at 2 years, respectively. Definitive radiation therapy was completed in 13 of 13 patients (100%), and local control was attained in 9 of 13 patients at 6 months (62%). Palliative radiation therapy was completed as intended in 7 of 11 (64%), and effects of palliation were observed in 9 of 11 patients (81%). Acute dermatitis, mucositis, pharyngitis, esophagitis, and cystitis of grade 2–3 related to the definitive radiation therapy were tolerable for the patients with good PS. It took 3–7 weeks (median 5) for acute moist desquamation of six lesions of skin cancer to heal. Depending on the radiation doses, grade 1–2 atrophy of skin and telangiectasia were documented for eight patients followed up for more than 1 year. A brief description of representative case is presented. Conclusion: Patients older than 90 years with good PS may tolerate the acute effects of radiotherapy administered according to conventional fractionation schedules. Definitive radiation therapy should be considered, when applicable, even for patients older than 90 years.

Purpose: In vivo phosphorus (31P MR spectroscopy (31P MRS) was performed in the human liver in order to investigate the relation between: the ratios of phosphorus metabolites in the liver; the histopathological grading of chronic hepatitis; and the response to therapy Material and Methods: Hepatic 31P MRS using the DRESS method (depthresolved surface-coil spectroscopy) was carried out in 45 patients with chronic viral hepatitis or autoimmune hepatitis, and in 16 control subjects. We measured the ratios of the peak areas of phosphomonoesters (PME), inorganic phosphate (Pi), or phosphodiesters (PDE) to the peak area of β-adenosine triphosphate (ATP) Results: The PDE/ATP ratio of patients with chronic hepatitis or liver cirrhosis was lower than that of control subjects (liver cirrhosis=0.74; chronic active hepatitis=1.13–1.21; normal=1.43); only a small difference was found in the PME/ATP and Pi/ATP ratios. There was no correlation between the spectra and histopathological grading or response to therapy, but the response to therapy was poor when a reduced PDE/ATP ratio was present Conclusion: The PDE/ATP ratio measured by 31P MRS makes it possible to identify the transition of chronic active hepatitis into liver cirrhosis with a poor response to therapy

We correlated high-resolution CT (HR-CT) images of 30 surgically resected epidermoid carcinomas in peripheral lung fields with pathologic findings. We classified peripheral epidermoid carcinomas into three types based on HR-CT findings. All tumors showed a notch along their margin. Type 1 shows scanty speculations without the convergence of surrounding lung structures. Type 2, which has two subtypes, shows a spiculated border with the convergence of peripheral lung structures. Type 2a has fine irregularities in its border, while type 2b has few fine irregularities. The convergence of peripheral lung structures seen in type 2 carcinoma is caused by the presence of scar tissue within tumors. Speculations corresponded to tumor extension or lymphocytic infiltration, sometimes along pulmonary vessels or interlobular septa, and fine irregularities seen in type 2a corresponded to summation of fibrous thickening of alveolar septa. Nine tumors showed varying-sized cavities, which were caused by the circulatory disturbance and/or central necrosis seen in tumor nests. In conclusion, HR-CT images were well correlated with pathologic findings of the resected specimens; however, some type 2a tumors may mimic adenocarcinoma on HR-CT findings.

We examined the usefulness of a new medical facsimile (MFAX) system in recording and transmitting various kinds of medical images, including X-ray images and colored histopathologic images. The system consists of an image scanner, a magnetic disk for image storage, a transmission circuit and a thermal image printer. Transmission time for a FCR (Fuji computed radiography) image by super-fine mode was 6 minutes. We used ROC (receiver operating characteristics) curves to evaluate the ability of eight radiologists to detect the small simulated nodules placed on an anthropomorphic chest phantom and shown on MFAX images. The radiologists observed both the FCR films and MFAX copies and determined the presence or absence of simulated nodules using five confidence levels. The results obtained for FCR films and MFAX images showed no statistically significant difference.

The detectability of simulated nodules placed on a chest phantom and shown on FCR images has been studied. Different tube voltages (130 kVp, 100 kVp), presence or absence of compensation filter, various sites and different sizes (5 mm/10 mm) and configurations (spherical or broad based) of the nodule were examined. 112 FCR chest phantom images were evaluated by ten radiology specialists utilizing ROC analysis. The detection rate for nodules was influenced in general by the site. The detection rate was as follows in decreasing order: intercostal, overlaid with one rib, two ribs, diaphragm and heart. Detection of nodules of 10 mm in height was mainly influenced by the density of the lung where the nodule was located, whereas that of nodules of 5 mm in height was more dependent on the site of the nodule, probably greatly influenced by the amount of structure mottle. Spherical nodules of 5 mm in height were more frequently recognized than the broad-based ones. High kVp (130 kVp) resulted in a higher detection rate for both sizes of nodules than low kVp (100 kVp). Detection of spherical nodules overlying the heart or diaphragm was improved with the use of a compensation filter.

We compared the ability of standard film-screen chest radiographs to detect simulated pulmonary nodules. The radiographs were taken with different X-ray filters and tube voltages. Detection capability was analyzed utilizing receiver operating characteristic (ROC) curves formed from the interpretation of six readers. Nodule detection was slightly better in images obtained with a tube voltage of 135 kVp than with one of 100 kVp (not statistically significant). Approximately equal detection performance was shown by a conventional film-screen system and FCR with three X-ray filter sets: a copper filter backed by aluminium, a tungsten filter backed by yttrium and aluminium, and a lead filter backed by yttrium and aluminium. Results showed less X-ray exposure with the two latter filter sets. Unenhanced FCR images taken with approximately the same X-ray exposure as conventional radiographs showed nearly equal ability to detect the simulated nodules.

To determine a suitable combination of X-ray filter and tube kilovoltage for Fuji Computed Radiography (FCR), to provide better detection of pulmonary nodules and reduce patient exposure, we compared observer performance with different X-ray filters and tube voltages. Radiographs were obtained with a copper filter backed by aluminium, with a tungsten filter backed by yttrium and aluminium, and with a lead filter backed by yttrium and aluminium, at both 100 kVp and 135 kVp. Observer performance in detecting simulated lung nodules, which were placed on the posterior aspect of a chest phantom, was compared using receiver operating characteristic (ROC) techniques for each combination of the X-ray filter and tube voltage. The results of the study indicated that 1) nodule detection was superior for the images obtained with 135 kVp as compared with 100 kVp; 2) approximately equal detection rates were obtained for the three X-ray filter sets, although results with the tungsten filter were slightly inferior to the other two filters; and 3) the absorbed dose may be reduced by 30% with the use of a lead filter backed by yttrium and aluminium compared with a copper filter backed by aluminium. We conclude that chest radiography with FCR should preferably be conducted with a higher kilovoltage, e.g., 135 kVp rather than 100 kVp, to ensure a higher detection rate of pulmonary nodules and in conjunction with a lead filter backed by yttrium and aluminium to reduce X-ray exposure to the patient.

We describe the magnetic resonance (MR) appearance with pathologic correlation of six pulmonary hamartomas. All six tumors showed intermediate signal intensity on T1-weighted images and high signal intensity on T2-weighted images. Four of the six tumors showed a lobulated appearance separated by septa on precontrast T1-weighted or T2-weighted images. Gadolinium-enhanced T1-weighted images showed marked enhancement of the septa that separated the tumors into less well enhanced lobules; this was seen in all six tumors. Comparison between MR images and pathologic specimens showed that the regions with less enhancement corresponded to core cartilaginous tissue and septa; areas of marked contrast enhancement corresponded to cleft-like branching mesenchymal connective tissue that dipped into the cartilaginous core. MR images correlated well with the surgically resected tumors.

PURPOSE: To investigate the value of gadopentetate dimeglumine-enhanced MR imaging in determining the extent of laryngohypopharyngeal cancer. METHODS: Unenhanced and contrast-enhanced T1-weighted, proton-density-weighted, and T2-weighted images from 24 patients with laryngohypopharyngeal cancer were reviewed and compared with the pathologic findings of resected specimens. In 18 patients, ex vivo MR images of the resected specimens were also compared with pathologic findings. RESULTS: Laryngohypopharyngeal cancer showed intermediate intensity on T1-weighted and proton-density-weighted images, high intensity on T2-weighted images, and moderate enhancement on T1-weighted enhanced images. Cartilage-invaded tumor enhanced moderately, whereas unossified cartilage in contact with tumors but without tumor invasion showed no enhancement. Laryngohypopharyngeal mucosa enhanced intensely; endolaryngeal muscles enhanced less. CONCLUSIONS: Enhanced MR images were more useful in assessing the extent of tumors and the presence of laryngeal cartilage invasion than were proton-density-weighted and T2-weighted images.

The appropriate radiation dose and field for the treatment of intracranial germinoma were investigated in 33 patients. Recurrences were observed in 4 cases treated with local field irradiation only, and all of them were recognized at the margin of the radiation field or under the dose (less than 25 Gy) area. This suggests that whole cranial irradiation (dose of 25 to 30 Gy) should be added even if the tumor is solitary. The effective dose for cerebrospinal dissemination appears to be 25-35 Gy, but prophylactic CNS irradiation seems unnecessary for patients who have not undergone surgical procedures. Changes in mental status were seen in 5 patients (26.3%). Doses of over 59 Gy may be related to this complication.

MR images in 17 patients with surgically proved thymomas (12 malignant and five benign) were reviewed and compared with pathologic specimens. In nine cases, MR images of excised specimens also were made and evaluated. On T2-weighted images, 11 of 12 malignant thymomas had an inhomogeneous signal intensity, half with and half without a lobulated internal architecture. None of the five benign thymomas had a lobulated internal architecture, and they all had a moderately or slightly inhomogeneous signal. Cystic regions and/or hemorrhage were noted pathologically, and corresponded to areas of inhomogeneous high signal intensity seen on T2-weighted images. Examination of the excised specimens in malignant thymomas showed that the lobulated configuration seen in the tumors was caused by thick fibrous septa. Our experience suggests that, although calcification cannot be identified, MR is helpful in making a differential diagnosis of mediastinal tumors and in determining malignancy of thymoma.

Changes in the level of S-(1,2-dicarboxyethyl)glutathione (DCE-GS) with time were determined during regeneration of rat liver after partial hepatectomy. The DCE-GS level increased in regenerating rat liver, reaching a maximum level (4.7-fold) on day 2 and reverted to the normal level in 1 week. During the liver regeneration process, the activity of DCE-GS-synthesizing enzyme in the liver retained its control level, while the level of glutathione--a substrate of the enzyme in the liver--fluctuated in parallel with that of DCE-GS.

Highly polymorphic HLA systems have greatly contributed to paternity testing and personal identification in forensic work. Recently HLA alleles in the class II region has been identified easily at the nucleotide level using PCR method. The PCR procedure involves the PCR-SSO (sequence specific oligonucleotide) method and the modified PCR-RFLP method (1). Those two methods permit precise and direct analysis of allelic variations by using less than 1 ng of DNA. The modified PCR-RFLP method provides a simpler and more rapid technique for accurate definition of the HLA-class II alleles. In this study, HLA-DQA1 and -DPB1 alleles were defined in 150 unrelated healthy Japanese individuals using the modified PCR-RFLP method. Exclusion probability (EP) was calculated from the allele frequencies of DQA1 and DPB1 obtained in this population.

CT images of 24 patients with head and neck lymphoma were retrospectively reviewed, compared with ultrasonograms, and compared with CT images of 13 patients with lymph node metastases. In nine (38%) of 24 patients, some lymph nodes with lymphomatous involvement showed a spotty or linear pattern of contrast enhancement. In two of these nine patients, a dendritic pattern of contrast enhancement between multiple enlarged lymph nodes was observed. The same pattern appeared as spotty, linear, or dendritic hyperechoic areas on the ultrasonogram. None of 13 patients with lymph node metastases showed a spotty, linear, or dendritic pattern of contrast enhancement. Ten of 13 (77%) showed ring-like contrast enhancement on CE-CT images. The spotty or linear contrast enhancement in enlarged lymph nodes and the dendritic contrast enhancement in confluent lymph nodes could be useful CT findings in diagnosing nodal involvement with malignant lymphoma.

To study the detailed normal ultrasonic anatomy of the pleura and chest wall, high resolution (7.5 MHz) ultrasonograms were obtained from cadaver chest wall specimens and compared with thin section computed tomograms and anatomical specimens. Ultrasonograms show three layers of the intercostal muscles (internal, external and innermost), covered by the "echogenic pleural line." The "echogenic pleural line" is caused by composite echoes from the inner parietal pleura, and the outer endothoracic fascia, with the fatty tissue covering both sides of the fascia, which are located deep to the chest wall muscles. On ultrasonograms, the subpleural fat tissue, when abundant, appeared as an apron-like structure hanging down from the inner surface of the rib (subpleural fat pad), or diffuse fat accumulation mimicking the pleural thickening.

Emphases in JT-60 experiments are placed on (1) lower-hybrid (LH) current drive characteristics with a multi-junction type launcher, and (2) the confinement study with combination of neutral beam injection LH current drive and pellet injection. The new multi-junction LH launcher provides a sharp N/sub /// spectrum with high directivity for N/sub ///=1-3.4. The current drive efficiency and the radial distribution of high energy electron production show clear correlation with injected N/sub ///: the current drive efficiency has the maximum at low N/sub ///( approximately 1.3) while flattening of plasma current is more effective in large N/sub ///. A broad radial distribution of high energy electron current and approximately 30% reduction in sawtooth inversion radius were obtained by high N/sub /// ( approximately 2.5) LH injection. To fully suppress the sawtooth activity, low N/sub /// ( approximately 1.3) injection was found to be more effective. Improved energy confinement has been obtained with hydrogen pellet injection. Energy confinement time was enhanced up to 40% relative to usual gas fuelled discharges. The discharge has a strongly peaked electron density profile with ne(0)/(ne) approximately 5 and ne(0) approximately 2.0*1020 m-3. The improved discharges are characterized by a strongly peaked pressure profile within the q=1 magnetic surface, and degrades when a large sawtooth recovers or the pressure gradient may reach a critical value. When large (3 mm, 4 mm) and fast (2.2 km/s) pellets were injected, 30% energy confinement improvement was obtained even during the NB heating of 14 MW. Further investigations of IDC characteristics have been made. The oxygen impurity lines from the main plasma and the main radiative loss drop first. Then the plasma stored energy starts to rise. The particle recycling is reduced around the main plasma, and is localized in the neighborhood of the X-point with a time lag of approximately 0.2 sec. Eventually the discharge shows a significant remote radiative cooling power at the divertor region.

The normal size of lymph nodes for each region of the hilum was determined by direct measurement of the short and long diameters of each node in the transverse plane of the node and the longitudinal diameter in the vertical plane of the node in 30 adult cadavers. The mean short transverse diameters ranged from 3.2 to 6.4 mm, the mean long transverse diameters ranged from 4.9 to 10.0 mm, and the mean longitudinal diameters ranged from 5.7 to 11.3 mm. The largest mean transverse diameters were found in the anterior upper lobe (AUL) and the inferior interlobar (IIL) regions. We noted a different maximum normal size for lymph nodes in each region of the hilum and determined the standard maximum normal short transverse diameters to be as follows: 12 mm for nodes in the right AUL and IIL regions, 10 mm for nodes in the right superior interlobar region and the left AUL and IIL regions, and 8 mm for nodes in other regions. Both the maximum normal long transverse diameters and the longitudinal diameters showed a wider variation, ranging from 18 to 10 mm and from 20 to 12 mm, respectively.