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We present experimental characterization of a 20-kV, 130-mA thermionic electron gun, which is a component of a ${W}$ -band traveling-wave tube (TWT) power amplifier. The electron beam is strongly focused by a 6.6-kG permanent magnet solenoid, producing a peak current density up to 800 A/cm2. The cathode temperature, focus electrode voltage, and modulating anode voltage are varied to characterize the emitted cathode current and beam transport through the beam tunnel of the TWT RF circuit. We observe the variation of the cathode current from 107 to 155 mA and peak beam transmission of 95% measured at the collector. Experimental results are compared to 2-D simulations with the electron gun and collector design code MICHELLE.

We present the experimental demonstration of a traveling-wave tube (TWT) power amplifier operating in the ${W}$ -band (75–110 GHz) frequency range. The device is based on a serpentine waveguide (SWG) amplification circuit, a slow wave circuit type capable of high power and broad instantaneous bandwidth in the upper millimeter-wave range. A 20 kV, 140-mA round solenoid-focused electron beam powers the device. At 20 kV, we measure 215 ± 2 W peak RF output power at 93 GHz with 20.1 ± 0.15 dB saturated gain, pulsed at 0.1% duty. We observe 10-GHz instantaneous amplification bandwidth at 100-W minimum output power, covering the range 88–98 GHz. Operating at 20.8 kV, the TWT produces 285 ± 3 W at 91 GHz with 22.4 ± 0.15 dB gain, and 7 GHz, 3-dB bandwidth. The peak electronic efficiency measured is approximately 10%.

We present testing of a W-band traveling-wave tube (TWT) based on a serpentine waveguide circuit, powered by a 20 kV, 130mA electron gun. We measure peak output power of 215±2W at 93 GHz with 20.1±0.15dB saturated gain, and>100 W from 88-98 GHz, pulsed at 0.1% duty. Operating at 20.8 kV, the TWT produces 285±3W at 91 GHz with 22.4±0.15dB gain.

We present experimental characterization of a 20 kV, 130 mA thermionic electron gun in a W-band TWT. The gun heater voltage, focus electrode voltage, and modulating anode voltage are swept to characterize the performance of the emitted cathode current and beam transport through the RF circuit. We observe variation of the cathode current from 107 to 155 mA and peak beam transmission of 95% at the collector. Experimental results are compared to 2D MICHELLE simulations.

Development overview and test results of a multibeam inductive output tube that produces over 1.2 MW peak power at 704 MHz with over 65% efficiency are presented. This is a collaborative effort between Thales Electron Devices and Communications & Power Industries to design and fabricate a new RF source for the European Spallation Source. The first prototype unit has been designed and built. Initial test at CERN demonstrated output power of 1.2 MW peak, efficiency of 69.8%, and gain of 21.4 dB at 1-ms operation. When the pulselength was increased to 4 ms, instability in the RF output pulse developed as the result of a mechanical contact issue in the output window. The prototype is in the process of being repaired and the unit will be returned to CERN for full characterization and final testing in early 2018.

We report on hot test measurements of a wide-bandwidth, 220-GHz sheet beam traveling wave tube amplifier developed under the Defense advanced research projects agency (DARPA) HiFIVE program. Nano-computer numerical control (CNC) milling techniques were employed for the precision fabrication of double vane, half-period staggered interaction structures achieving submicrometer tolerances and nanoscale surface roughness. A multilayer diffusion bonding technique was implemented to complete the structure demonstrating wide bandwidth (>50 GHz) with an insertion loss of about −5 dB achieved during transmission measurements of the circuit. The sheet beam electron gun utilized nanocomposite scandate tungsten cathodes that provided over 438-A/cm2 current density in the 12.5:1 ratio sheet beam. An InP HBT-based monolithic microwave integrated circuit preamplifier was employed for TWT gain measurements in the stable amplifier operation region. In the wide-bandwidth operation mode (for gun voltage of 20.9 kV), a gain of over 24 dB was measured over the frequency range of 207–221 GHz. In the high-gain operation mode (for gun voltage of 21.8 kV), over 30 dB of gain was measured over the frequency range of 197–202 GHz. High-power tests were conducted employing an extended interaction klystron.

We present fabrication and testing of RF components for a W-band serpentine waveguide TWT. Broadband ceramic RF windows and loads exhibit reflection lower than −20 dB across the TWT operating band, nominally 87–100 GHz. End-to-end cold test of the entire tube assembly, including interaction circuit, shows a clean passband better than −15 dB, in agreement with simulation. We discuss details of the fabricated components and electromagnetic cold test results.

High-power millimeter-wave amplifiers are required for various new and emerging applications, such as point-to-multi-point wireless high-data-rate communications over multi-km ranges for residences and businesses. Driven largely by these requirements, both civilian and defense-related, researchers over the last decade have dramatically increased the power and bandwidth of a variety of vacuum electronic amplifiers in the millimeter-wave regime. The Naval Research Laboratory (NRL) has played a key role in the development of the science and technology that has made possible this increased performance. One attractive class of devices to arise from these efforts is the power booster, a relatively low-gain but very high-power amplifier that can produce significantly higher power than state-of-the-art amplifiers driven by comparable electron beams. At Ka band, NRL power boosters have produced from 1.5 to 4 kW of peak power from electron beams of ∼20 kV and up to 600 mA. The 3–5 dB gain of these amplifiers allows compact designs and high interaction efficiency. For example, with a multistage depressed collector the 4 kW output power device can achieve a power added efficiency of >40%.

We present the first vacuum electronic traveling wave amplifier to incorporate an interaction circuit fabricated by ultraviolet (UV) photolithography and electroforming, demonstrating over 60 W of output power at 214.5 GHz from a 12.1 kV, 118 mA electron beam. The tube also achieved an instantaneous bandwidth of ${\sim}{\rm 15}~{\rm GHz}$ in $G$ -band in the small signal regime. The all-copper circuit was fabricated in two layers using a UV-transparent polymer monofilament embedded in the photoresist to form the beam tunnel prior to electroforming. Effects arising from fabrication errors and target tolerances are discussed. This microfabrication technique and demonstration paves the way for a new era of vacuum electron devices that could extend into the 1–2 THz range with advances in high-current-density electron guns.

We present development progress for a 233 GHz hybrid serpentine waveguide TWT amplifier employing microfabrication techniques based on UV-LIGA. Maximum output power from the circuit is predicted to exceed 140 W from a 20 kV, 124 mA electron beam. Updates include progress of the circuit microfabrication and testing, window tuning, and electron gun.

We describe the progress of the development of a multi-beam inductive output tube (MB-IOT) that will produce over 1.2 MW peak power at 704 MHz with over 65% efficiency. This is a collaborative effort between Thales Electron Devices (TED) and Communications & Power Industries (CPI) to design and fabricate a new RF source for the European Spallation Source (ESS). Main design features and predicted performance will be presented.

We present electromagnetic cold-test measurements of BeO ceramic pillbox vacuum windows for a 220-GHz traveling-wave tube amplifier. Transmission and reflection measurements show better than 20 dB return loss over a 25 GHz bandwidth, with band centers in the range of 212-225 GHz. We observe tuning of the window response as the circular waveguide length is changed. High-power testing is performed at 2.5 W, 100% duty at 218 GHz.

In this paper we resurrect an idea originally proposed by Serafini[1] in 1992 for an RF photocathode gun capable of operating simultaneously at the fundamental frequency and a higher frequency harmonic. Driving the gun at two frequencies with the proper field ratio and relative phase produces a beam with essentially no rf emittance and a linear longitudinal phase space distribution. Such a gun allows a completely new range of operating parameters for controlling space charge emittance growth. In addition, the linear longitudinal phase space distribution aids in bunch compression. This paper will compare results of simulations for the two-frequency gun with the standard rf gun, and the unique properties of the two-frequency gun will be discussed.

口腔外科領域の末期癌患者は原発巣や頸部転移巣からの出血により死亡することがあり, そのために患者のQOLの著しい低下を招くことがある。今回我々は口腔癌の末期で原発巣や頸部転移巣から出血した患者に対して動脈塞栓術を施行した3例を経験したのでその概要を報告する。さらに塞栓術4日後に死亡した1例を除く2例について塞栓術前後のKarnofsky Performance Statusscale (KPS) と血清アルブミン値について比較検討した。その結果KPS, 血清アルブミン値は改善しQOLも改善したと考えられた。今回の経験から腫瘍から出血を生じた口腔癌の末期患者に対する塞栓術が患者のQOLの維持, 改善と延命につながると考えられた。

岡山大学歯学部附属病院第二口腔外科にて加療した口腔悪性黒色腫4例について臨床的検討を行った。対象症例の性別は男性2例, 女性2例, 年齢は57歳から75歳までであった。原発部位は下顎歯肉1例, 口蓋3例で初診時のUICC (1997) 分類はstage Ia期: 1例, stage II期: 1例, stage III: 2例であった。治療法は全例外科療法を施行し, 化学療法及び免疫療法またはホルモン療法を併用した。局所再発及び頸部リンパ節転移または遠隔転移をきたした2例が死亡例であった。他の2例は, 局所再発及び転移はなく, 経過観察期間は14年11ケ月と3年8ケ月であった。

1982年4月より1999年3月までに岡山大学歯学部附属病院第二口腔外科を受診し, 病理組織学的に粘表皮癌と診断された27例について臨床統計的検討を行ったので報告する。 (1) 性別発生頻度は, 男性16例, 女性11例。 (2) 年齢別発生頻度は平均63.0歳であった。 (3) 部位別発生頻度をみると大唾液腺2例, 小唾液腺25例。 (4) TNM分類ではT1が7例, T2が7例, T4が13例であり, Stage別では, Stage Iが7例, Stage IIが7例, Stage IVが13例であった。 (5) 治療法については, 24例に対して外科療法を施行し, そのうち外科療法の単独施行は13例, 化学療法および放射線療法の併用療法を施行したものは11例であった。 (6) 全体の5年累積生存率は69.4%で, Stage I, II症例が90.9%, Stage IV症例が46.4%であった。

The development of a broadband multi-kW Ka-band PPM focused TWT driver-booster combination is reported. The driver is an existing broadband coupled-cavity TWT1, employing a 2 stage depressed collector. The power booster is a newly designed sever-less folded waveguide TWT designed to provide 3–4 dB of additional gain2. The booster also uses a 2 stage depressed collector and a slightly modified version of the same electron gun used in the driver. In order to accommodate the high power output of the booster over the full operating band, a new racetrack window was successfully designed built and tested. The maximum booster output power of ∼ 1.75 kW at ∼ 750 Watt CC-TWT input power at 35 GHz has been demonstrated. The booster output power of 1.5 kW over 5 GHz and of 1.25 kW over 7 GHz centered at 35 GHz has been measured. Beam current interception of ∼ 7% has been observed in the power booster when operating > 1 kW, thus preventing a CW operation of the booster. The predictions from the 2.5D large signal TESLA-FW simulation code3 are in very good agreement with the measured data.

We describe our progress on the development of a Ka-band TWT driver-booster combination to produce >1kW over a 5 GHz band centered at 35 GHz. The driver is an existing > 500 Watt broadband coupled-cavity TWT 1 , employing a 2 stage depressed collector. The power booster is a newly designed sever-less folded waveguide TWT designed to provide 3-4 dB of additional gain. The booster also uses a 2 stage depressed collector and a slightly modified version of the same electron gun used in the driver. A photo of the driver and booster under test is shown in Fig. 1. The principal challenges that had to be met in a booster design were: (1) achieving the required output power and bandwidth, (2) ensuring stable booster operation under both small and large signal conditions and (3) presenting a good output match to the driver so that the driver remains stable.

We report on progress in developing a travelling wave tube amplifier with significant gain and power at 220 GHz. This paper provides an overview of the program, describing fabrication and test of slow-wave structures with bandwidths exceeding 50 GHz centered at 220 GHz, the production of a sheet electron beam, development of a solid state preamplifier delivering 50 mW to the tube with > 17 dB of gain and beam-wave simulation of the entire circuit leading to expected output powers of over 50 W. Two further papers from the group are also submitted to IVEC: from UC Davis describing the interaction structure fabrication and hot test, and from CPI describing the sheet electron beam, TWT design and beam - wave simulations. The tube is currently under test and results will be reported in this paper.

We study experimentally and theoretically, the effects of desynchronism modulation on short pulse free-electron laser (FEL) oscillators. We find that the output power and the micropulse length of the FEL beam oscillate periodically at the modulation frequency and the minimum micropulse length can be significantly shorter than that obtained without modulation. The FEL can operate during part of the modulation cycle in the normally inaccessible portion of the output power curve where the FEL gain is less than the cavity loss.

The effects of the crab spider, Misumenops tricuspidatus (Fabricius), on the larval survival of three ladybird species, Harmonia axyridis Pallas, Coccinella septempunctata L., and Propylea japonica L., in relation to aphids were investigated in the laboratory. Predation by the spider on the three ladybird species differed. All the larvae of C, septempunctata, none of H. axyridis, and an intermediate number of P. japonica were attacked and eaten by the spider. All the larvae of H. axyridis suffered mortality due to cannibalism or starvation in the treatments with and without a spider. In case of C. septempunctata, however, mortality in the early instars was significantly greater in the treatment with a spider than without a spider and no larvae developed into pupae due to predation. In the treatment without a spider, the majority of the larvae in the former treatment suffered mortality due to cannibalism or starvation, and only 13.3% of larvae developed into the adult stage. In the case of P. japonica, mortality was mainly attributed to predation in the treatment with a spider and only 26.7% became adult. In comparison, 86.7% of larvae survived to the adult stage in the treatment without a spider. In addition, in both H. axyridis and C. septempunctata, the development of young larvae was significantly slower in the presence of a spider, but this was not the case with the older larvae of H. axyridis, which indicates that the effect of the spider on larval development changed with the developmental stage of the larvae in this species. However, the spider had no significant effect on the developmental time of P. japonica larvae. Although both the spider and the ladybirds significantly affected the number of aphids, they did not have an additive effect on aphid abundance. The interactions between the spider and the ladybirds, such as intraguild predation or competition, caused them to reduce aphid population density less than the ladybirds did on their own. The effect of the spider on the larval performance of three predatory ladybirds was found to be unequal in terms of their vulnerability to predation and rate of larval development and it depended on the species and developmental stage of the ladybird.

We have studied the fabrication of filamentary Nd123 superconductor with high superconducting properties. The filamentary Nd123 precursor was prepared by the solution spinning method, through a homogeneous aqueous solution containing mixed acetates of Nd, Be, Cu, poly (vinyl alcohol) and organic acids. The filamentary sample was partially melted at 990/spl deg/C in flowing 0.1%O/sub 2/+Ar and oxygenated under various conditions. The transport critical current density (J/sub c/) for the samples was examined in magnetic fields up to 9.5 T at 77 K. The highest J/sub c/ value of 3.5/spl times/10/sup 4/ A/cm/sup 2/ at 77 K and 0 T and more than 10/sup 4/ A/cm/sup 2/ at 77 K and at 2 T was achieved for the filamentary Nd/sub 1.18/Ba/sub 2.12/Cu/sub 3.09/O/sub x/ superconductor by controlling the oxygenation conditions.

The oxygen controlled melt growth (OCMG) process for filamentary Nd123 superconductors has been studied to enhance the Jc values. The filamentary Nd1.18Ba2.12Cu3.09Ox (1) and Nd1.25Ba2.05Cu3.10Ox (2) precursors were prepared by dry spinning through a homogeneous aqueous solution containing mixed acetates of Nd, Ba and Cu, poly(vinyl alcohol). The calcined filaments were partially melted in flowing 0.1% O2+Ar. The Tc values of filament (1) was 94.5 K and 88.5 K for filament (2). By controlling the heating condition, maximum Jc values of 2.4×104 A/cm2 and 1.8×104 A/cm2 at 77 K and 0 T were attained for filaments (1) and (2), respectively. A window of the optimum heating conditions for filament (2) was narrow and the reproducibility of the high Jc value was poor.

We present the hot test results of a 220 GHz, serpentine waveguide vacuum electron amplifier showcasing a novel embedded monofilament microfabrication technique based on UV-LIGA. The instantaneous operating bandwidth exceeds 15 GHz and the small signal gain of the circuit is over 14 dB. By varying the voltage slightly, an operating bandwidth of almost 40 GHz is realizable with a minimum circuit gain of 7 dB across the band. A maximum power of just over 60 W was obtained at the output flange of the device, corresponding to a power of almost 80 W generated in the circuit.

The p53 tumor suppressor gene is the most commonly mutated gene in human cancer and is a frequent abnormality in oral squamous cell carcinoma and its precancerous lesions. MDM2 (murine double minute-2), a new proto-oncogene, may be associated with p53 gene products and may negatively affect the transcriptional activating function of p53. The purpose of this study was to investigate the incidence of MDM2 and its relationship to the expression of p53 in oral squamous cell carcinoma and precancerous lesions. Overexpression of p53 and MDM2 proteins was detected in 52 and 40% of oral squamous cell carcinomas, respectively. p53 gene mutation, absent in normal oral epithelium was observed in 31% of the carcinoma cases. Our finding suggested that MDM2 protein may be an alternative mechanism causing p53 protein dysfunction in oral squamous cell carcinoma.

Several new RF sources are being developed for accelerator and collider applications. Assembly is nearing completion of a multiple beam inductive output tube at 352 MHz. An annular beam klystron is being developed to produce 10 MW pulses at 1.3 GHz. The annular beam approach provides significant cost reduction over similar multiple beam devices. Fabrication is underway on a 10 kW, periodic permanent magnet klystron at 2.815 GHz. Permanent magnets eliminate the solenoid and associated power supplies and cooling requirements to reduce operational cost. Investigations are beginning on a novel approach for driving accelerator cavities using pulse shaping to increase coupling efficiency and dramatically reduce RF power requirements.

A sheet beam traveling-wave tube amplifier is currently being developed under the DARPA HiFIVE program. The device is designed to achieve over 50 W output power at 220 GHz with a power-bandwidth product exceeding 1,000 W-GHz. This paper will report on the design and fabrication status of the electron gun, RF circuit, and RF window with emphasis on simulation of beam-wave interaction using the MAGIC-3D code.

We report on the design and fabrication of a sheet beam traveling-wave tube (TWT) amplifier being developed under the DARPA HiFIVE program. The device is designed to achieve over 50 W output power at 220 GHz with a power-bandwidth product exceeding 1 kW-GHz.

Calabazas Creek Research, Inc. (CCR) and Communications & Power Industries, LLC (CPI) are assembling a 350 MHz, 200 kW CW, multiple beam inductive output tube (MBIOT)1. The MBIOT will be a new, high power, RF source for accelerators and colliders. This device will be a candidate RF source for the Advanced Photon Source at Argonne National Laboratory. The target efficiency is 70% with a predicted gain exceeding 22 dB.

Design is complete and fabrication and assembly are nearing completion on a 350 MHz, 200 kW CW, multiple beam inductive output tube (MBIOT). Seven electron guns in a circular array will be driven by a single input cavity. RF power is generated in a single, fundamental mode, output cavity. The device is predicted to achieve approximately 70% efficiency with 23 dB gain.

101 cases of squamous cell carcinoma of the oral cavity were investigated in regard to the relationship between tumor extent and (1) lymph node metastasis and (2) histological grading of malignancy.Immunohistochemical studies with laminin and type IV collagen were also carried out to assess the relationship between tumor extent and lymph node metastasis.It was suggested that five histological parameters (differentiation, nuclear polymorphism, mitoses, mode of invasion and mononuclear cell infiltration) and the basement membrane distribution pattern were not significantly related with tumor extent.In contrast, the mode of invasion and the basement membrane distribution pattern were closely correlated with lymph node metastasis.

A permanent magnet structure has been successfully designed and fabricated for the HiFIVE program. The design produces a peak field of 0.75 T within a gap length of 2.5 cm.

Design is complete and fabrication and assembly are progressing on a 350 MHz, 200 kW CW multiple beam inductive output tube (IOT). The device includes seven electron guns in a circular array. A single input cavity drives the fields for all seven electron guns. RF power is generated in a single output cavity. The device is predicted to achieve approximately 70% efficiency with 22 dB gain.

In this paper we report on a development program aimed at producing a travelling wave tube amplifier with significant gain and power at 220 GHz in a compact and lightweight package. This paper provides an overview of the program, describing development of nanoparticle scandate cathodes with current densities exceeding 100 A/cm2, MEMS fabrication and test of mm-wave waveguides and slow-wave structures with bandwidths exceeding 50 GHz centered at 220 GHz, and the production of a sheet electron beam with a current density exceeding 230 A/cm2 and an aspect ratio of 26∶1. These components may allow us to produce a 220 GHz, 50W high power amplifier with a hot bandwidth of > 20 GHz and a power-bandwidth product > 1000 W-GHz.

Large particle accelerator projects like the European X-ray Free Electron LASER (XFEL), which is under construction at DESY in Hamburg (Germany), or like the planned International Linear Collider (ILC) favor MBKs for their ability to generate high rf output powers at moderate electron beam energies. For the XFEL, Deutsches Electronen Synchrotron (DESY) ordered a prototype of a horizontally oriented, high-power MBK operating at 1300 MHz. This is CPGammas second generation 10 MW, L-band MBK, designated the VKL-8301B. The klystron is required to provide at least 65% efficiency at 10 MW peak rf output and more than 3 MHz instantaneous -l dB bandwidth. Average power and rf pulse length are 150 kW and 1.5 ms, respectively. Our design uses six off-axis electron beams for low cathode current density and thus longer cathode life. For the rf cavities we are utilizing fundamental-mode ring resonators. This ensures sufficient beam separation while still keeping the overall diameter of the device small in order to reduce cost. A more in-depth report on our design process and the tools we used was presented at the 2008 ICOPS. At the time of submission of this paper, initial rf hot test data were taken at reduced duty and pulse width while operating into well-matched output loads. At 0.42% rf duty, a peak rf output power as high as 11.2 MW was achieved, which corresponds to a 74% efficiency. The electron beam interception at and close to saturation was fairly high. Preliminary measurements of body power and the high efficiency indicate that mostly low-energy electrons past the output cavity gaps are involved in the klystron body interception in that operating condition. Initial optimization of the electromagnet for lower interception resulted in a 70% reduction of the rf body current, but this was accompanied by a noticeable drop in rf output power, efficiency (down to 67%) and gain. The klystron performance was stable for all operating conditions encountered so far. Further optimization of the magnetic field balance still has to be carried out for low body current and high efficiency at all required operating conditions, including operation into an output mismatch up to 1.2:1 VSWR. A more complete set of data taken after optimization and tuning will be presented at the conference.

We describe the simulation of an inductive output tube (IOT) using the particle-in-cell code MAGIC. Simulations were performed to analyze three basic processes in an IOT: formation of bunched electrons beams from a gridded electron gun, interaction between bunched beams and rf field in a resonator, and spent beam collection with a multi-stage depressed collector. There is excellent agreement between simulation results and experimental data.

Final design and fabrication are in progress on a 350 MHz, 200 kW CW, multiple beam, inductive output tube (IOT). The device includes seven electron guns in a circular array. A single input cavity drives the fields for all seven electron guns. RF power is generated in a single output cavity. The device is predicted to achieve approximately 70% efficiency with 22 dB gain.

CPI has designed and is currently in the process of building a prototype of a horizontally oriented, ≥10 MW, ≥65% efficiency multiple beam klystron (MBK) operating at 1300 MHz. The klystron, designated the VKL-8301B, was ordered by DESY for the European XFEL. The klystron was designed using of sate-of-the-art multi-dimensional design codes to ensure that all performance requirements are exceeded. Initial rf hot test data at reduced duty and pulse width produced a peak saturated rf output power in excess of 11 MW and 70% efficiency, which was however accompanied by high beam interception. Operation at full duty and pulse width as well as adjustment of the focusing and retuning the cavity frequencies impacted output power and efficiency. A compromise was found to satisfy all required operating conditions, including operation into a higher output mismatch. Complete test results will be presented at the conference.

A quantitative assay method for epidermal growth factor receptors (EGFRs) of human tumor tissues was established, based on enzyme‐labeled avidin‐biotin (LAB) interaction with anti‐human EGFR monoclonal antibody 52SIgG. A standard calibration curve for EGFR estimation in human tumor tissues was obtained with A431#8 cells cloned from A431 human epidermoid carcinoma cell line. The coefficient of variance for the standard curve was below 35% in the application to tumor tissues from nude mice implanted with human tumor cell lines. The minimum tissue amount required for the quantitative assay was around 0.1 g (wet weight). Using the LAB method, the correlation between the level of EGFR number and tumor malignancy was examined for 14 human squamous cell carcinomas (SCCs) from the oral region. Seven of the SCCs showed a more than two‐fold higher EGFR number compared to normal gingival tissues. Three highly aggressive carcinomas with poor prognosis possessed five to ten times higher levels of EGFR number than normal tissues. The elevated EGFR level in the SCCs seems to correlate to increasing tumor size and the stage of SCCs as clinically classified according to the 1987 UICC TNM system.

We describe a design for a coaxial inductive output tube (IOT) that operates in the 200 MHz range with 250 kW CW output power. Of particular interest are formation of a radial beam with a cylindrical gridded gun, and high efficiency RF interaction in a coaxial output cavity.

We report a case of intra-osseous carcinoma arising from a mandibular cyst. An 81-year-old woman visited our hospital because of a right mandibular swelling. Radiographic examination showed a multilocular radiolucent lesion and bone expansion, extending from the midline to the right mandibular angle. The clinical diagnosis was a mandibular cyst and marsupialization was performed. The histopathological specimen showed a cyst wall with an epithelial layer and connective tissue. After marsupialization, the swelling and the radiolucent area of the mandible decreased. However, about 7 months later, the mesial region of the lesion became swollen again, and it was biopsied. At that time, we obtained a pathological diagnosis of squamous cell carcinoma.Marsupialization does not permit histopathological examination of all sites of the lesion. Therefore, when it is performed for large mandibular cysts such as in our case, we should consider the posibility of an intra-osseous carcinoma arising from the lesion.

Recently, some patients, receiving long-term antipsychotic therapy, particularlywith phenothiazines, have been reported to die suddenly and unexpectedly. These patients may have underlying diseases of organs such as the liver, heart and endocrine glands. General anesthesia and surgery can be difficult in these patients. Therefore, care should be taken with regard to drug therapy (dosage and treatment period), laboratory findings, and general condition.