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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%.

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 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 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。

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.

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 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 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.

We present an experimental and theoretical study of the effect 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 that the minimum micropulse length during the cycle can be significantly shorter than that which can be obtained without modulation. For example, when the desynchronism of our FEL is modulated at 40 kHz, the minimum measured micropulse length is 300 fs. Without modulation the minimum is about 700 fs. We show that when the desynchronism is modulated, the FEL can operate for part of the cycle in the normally inaccessible portion of the output power curve where the FEL gain is less than the cavity losses. It is even possible for the FEL to operate periodically in the region of negative desynchronism where gain, as normally defined, does not exist.

Herpes Zoster is the viral disease of skin and mucosa characterized by grouped vesicular eruptions along a peripheral nerve, and it is thought that cell-mediated immunoactivity is involved. A case of Herpes Zoster in the right region along the second trigeminal nerve branch of a 58-year-old male was reported. The relation between clinical behavior and serum immunological examination was studied. The results were as follows:1. A possible decrease of cell-mediated immunoactivity in the serum examination at the initial stage of the disease.2. The comlement fixation test (CF test) is dependable as a differential diagnostic procedure for Herpes Zoster.3. Close relations between complement system, antibody titer and clinical behaviors.

Clinical evaluation of Cefbuperazone (CBPZ) in 63 cases of various infections inthe oro-facial region was carried out. Bacteria were isolated from the infectious lesions and their sensitivity to Cefbuperazone was tested. The results are summarized as follows.1. CBPZ was subjectively evaluated by doctors who used the drug, and considered excellent in 20 cases, good in 32 cases, fair in 6 cases and poor in 5 cases, the effectiveness rate being 82. 5%. On the other hand, CBPZ was also estimated by way of a scoring system evaluation and considered excellent in 15 cases, good in 37 cases and poor in 11 cases, the effectiveness rate being 82. 5%.2. Bacteria were able to be isolated in 57 cases (90. 5%). Of the isolated 90 strains, 21 were anaerobic (23. 3%). These isolated anaerobics were highly sensitive to CBPZ.3. No remarkable side effect was observed, but elevation of S-GOT in one case, S-GPT in two cases and ESR in two cases were observed.According to these results, CBPZ was evaluated to be useful antibiotics for various infections in the field of oral surgery.

A case of Schwannoma that occurred at the right palate was reported. The clinical impression was suspected pleomorphic adenoma, and the lesion was surgically excised under general anesthesia. It was noticed during the operation that the tumor adhered to the greater palatine nerve. Histopathologically it was diagnosed as Schwannoma (Antoni A type), so it was suggested that the tumor had a close relation to the greater palatine nerve. Clinical behaviors were compared with other Schwannomas already had reported. From histological, electronmicroscopical, and immunohistochemical findings, the origin of the tumorwas also discussed.

Typical Sturge-Weber syndrome of a 27 year-old female was reported. She had vascular nevus on the right side of her face, right maxillary hemangioma, epilepsy, intercranial calcification, paralysis on the left side of her extremitie 1 and glaucoma.Hemangioma on the right maxilla associated with this syndrome was treated successfully with carbon dioxide laser. The tumor was cut by focused beam and small blee ding vessels were sealed off by defocused beam. Bleeding was minimal. Postoperative healing was excellent, but left maxillary central incisor was damaged by carbon dioxide beam.We considered that vascular-rich lesions were effectively extirpated with carbon dioxidelaser. But the manipulation of the apparatus was a little difficult in molar region cases, therefore, without careful operation, surrounding tissue might be damaged.

Verruciform xanthoma is a non-tumorous lesion of unknown etiology and uncertain nature, first described by Shafer in 1971.Histologically the characteristic features of the lesion are the presence of rete pegs extremely elongated and large, swollen foam cells or xanthoma cells.This paper presented the case of an 80-year-old female with a lesion at the right lateral margin of the tongue. Histochemical and immunohistochemical detections were also made, and the origin of histiocytes as to foam cells were discussed. In addition the reports concerning it in Japan were reviewed.