Observation of Dynamic Interactions between Fundamental and Second-Harmonic Modes in a High-Power Sub-Terahertz Gyrotron Operating in Regimes of Soft and Hard Self-Excitation

Dynamic mode interaction between fundamental and second-harmonic modes has been observed in high-power sub-terahertz gyrotrons [T. Notake et al., Phys. Rev. Lett. 103, 225002 (2009); T. Saito et al. Phys. Plasmas 19, 063106 (2012)]. Interaction takes place between a parasitic fundamental or firstharmonic (FH) mode and an operating second-harmonic (SH) mode, as well as among SH modes. In particular, nonlinear excitation of the parasitic FH mode in the hard self-excitation regime with assistance of a SH mode in the soft self-excitation regime was clearly observed. Moreover, both cases of stable twomode oscillation and oscillation of the FH mode only were observed. These observations and theoretical analyses of the dynamic behavior of the mode interaction verify the nonlinear hard self-excitation of the FH mode

永久歯の先天的欠如に関する臨床統計調査

永久歯の先天性欠如（以下，先欠とする）は，最も高頻度に発現する顎顔面領域の先天異常であり，様々な不正咬合を引き起こし，交換期における咬合誘導あるいは，永久歯列期における歯の排列に際して苦慮することが多い．しかし，歯科矯正用アンカースクリューの登場により，治療方針に多様性が生まれ，先欠を有する患者に対して，欠損部位・歯数に影響されない，顎顔面骨格形態に則した治療方針が選択できる症例が増加している．このような症例の治療計画を立案する際には，先欠が顎顔面骨格形態へ与える影響を明らかにしておく必要がある．そこで，今回我々は不正咬合患者における第三大臼歯を除く永久歯の先欠の実態把握，ならびに先欠が顎顔面骨格形態に及ぼす影響の解明を目的として臨床統計学的な検討を行った． 2011年4月から2016年3月までの5年間に不正咬合を主訴として徳島大学病院矯正歯科を受診した患者のうち，口唇裂・口蓋裂やその他の先天異常を有する患者，矯正歯科治療の既往を有する患者および先欠の確認が不可能であった患者を除外した653名（男性233名，女性420名）を対象とし，調査を行った．その結果，以下の所見を得た． 1．先欠を有する患者は96名（14.7％）であり，男女比は1.13：1と男性がやや多かった．1人あたりの先欠歯数としては，1歯のみの欠損が最も多く，49.0％を占めた． 2．歯種別発現頻度は，上下顎ともに第二小臼歯，側切歯の順で高かった． 3．先欠を有する患者を上顎先欠群，下顎先欠群，上下顎先欠群に分類し，比較検討を行ったところ，前歯部被蓋関係については，下顎先欠群においてoverjetが最も大きかった．顎骨の前後的位置関係については，下顎先欠群において∠ANBが大きく，∠SNBが小さくなる傾向を認め，上顎先欠群，上下顎先欠群では∠SNAが小さくなる傾向を認めた． 以上の所見より，先欠が顎顔面骨格の成長・発育に影響を及ぼす可能性が示されたことから，先欠に関連した顎顔面骨格形態の特徴を考慮した治療計画の立案が重要であることが示唆された

口唇裂・口蓋裂患者の歯数異常に関する調査

口唇裂・口蓋裂患者は，軟組織や骨の癒合不全だけでなく，永久歯の先天欠如や過剰などの歯数異常が認められ，歯科矯正学的対応に苦慮することも多い．そこで，口唇裂・口蓋裂患者における永久歯の歯数異常の実態を明らかにすることを目的として，1995年1月から2011年12月までの17年間に出生し，徳島大学病院矯正歯科を受診した口唇裂・口蓋裂患者（症候群を含まない）を対象とした調査を行い，以下の結果を得た． 1．調査資料が揃っている患者101名の男女比は，1：1.02であった． 2．顎裂保有者82名の顎裂部位は，1 ▼ 3の型が最も多く，次いで1 ▼23の型であった．（▼は顎裂部位を示す） 3．永久歯における歯数異常の発現率は63.4％であり，歯の欠如のみを有するものが50.5％，過剰歯のみを有するものは8.9％，歯の欠如と過剰歯をともに有するものは4.0％であった． 4．歯の欠如の歯種別頻度は，側切歯が最も多く，次いで第二小臼歯の順であった． 5．顎裂保有者のみを対象とすると，歯の欠如の発現頻度は披裂側で59.8％，非披裂側で24.3％であった． 以上のことから，口唇裂・口蓋裂患者での先天欠如歯の発現率は高いため，治療計画立案時に補綴治療を含めた包括的歯科治療の必要性が示唆された

ECCD Experiment Using an Upgraded ECH System on LHD

Electron cyclotron current drive (ECCD) is an attractive tool for controlling plasmas. In the large helical device (LHD), ECCD experiments have been performed by using an EC-wave power source, gyrotron, with a frequency of 84 GHz. The maximum driven current was ?9 kA with 100 kW injection power to plasma and 8 s duration of EC-wave pulse. These years, high-power and long-pulse 77 GHz gyrotrons were newly installed. An ECCD experiment with 775 kW injection power was performed. The 77 GHz waves of 8 s pulse duration sustained the plasmas. The EC-wave beam direction was scanned toroidally, keeping the beam direction aiming at the magnetic axis in X-mode polarization. In spite of the change in the EC-wave beam direction, plasma parameters such as the line-average electron density, the central electron temperature and the plasma stored energy were kept nearly the same values for the discharges, ?0.3 × 1019 m?3, ?3 keV and ?30 kJ, except for the plasma current. The plasma current showed a systematic change with the change in the beam direction for ECCD, and at an optimum direction with N// ? ?0.3, the plasma current reached its maximum, ?40 kA. Also, current drive efficiency normalized with density and power was improved by 50% compared with that at the former 84 GHz ECCD experiment

High Harmonic ECH Experiment for Extension of Heating Parameter Regime in LHD

High harmonic electron cyclotron resonance heating (ECH) can extend the plasma heating region to higher density and higher β compared to the normal heating scenario. In this study, the heating characteristics of the second-harmonic ordinary (O2) and third-harmonic extraordinary (X3) modes and the possible extension of heating regime are experimentally confirmed. At the same time, a comparative study using ray-tracing calculation was performed in the realistic three-dimensional configuration of the Large Helical Device. The O2 mode heating showed a 40% absorption rate even above the X2 mode cut-off density. The X3 mode heating using powerful 77 GHz gyrotrons demonstrated an increase of about 40% in the central electron temperature in the plasmas at β-value of about 1%. These results were quantitatively explained to some extent by ray-tracing calculations

The Human Anatomic Gene Expression Library (H-ANGEL), the H-Inv integrative display of human gene expression across disparate technologies and platforms

The Human Anatomic Gene Expression Library (H-ANGEL) is a resource for information concerning the anatomical distribution and expression of human gene transcripts. The tool contains protein expression data from multiple platforms that has been associated with both manually annotated full-length cDNAs from H-InvDB and RefSeq sequences. Of the H-Inv predicted genes, 18 897 have associated expression data generated by at least one platform. H-ANGEL utilizes categorized mRNA expression data from both publicly available and proprietary sources. It incorporates data generated by three types of methods from seven different platforms. The data are provided to the user in the form of a web-based viewer with numerous query options. H-ANGEL is updated with each new release of cDNA and genome sequence build. In future editions, we will incorporate the capability for expression data updates from existing and new platforms. H-ANGEL is accessible at http://www.jbirc.aist.go.jp/hinv/h-angel/

Experimental Results for Electron Bernstein Wave Heating in the Large Helical Device

Electron cyclotron heating (ECH) using electron Bernstein waves (EBWs) was studied in the large helical device (LHD). Oblique launching of the slow extraordinary (SX-) mode from the high field side and oblique launching of the ordinary (O-) mode from the low field side were adopted to excite EBWs in the LHD by using electron cyclotron (EC) wave antennas installed apart from the plasma surface. Increases in the stored energy and electron temperature were observed for both cases of launching. These launching methods for ECH using EBWs (EBWH) is promising for high-density operation in future helical fusion devices instead of conventional ECH by normal electromagnetic modes

A Small Bowel Ulcer due to Clopidogrel with Cytomegalovirus Enteritis Diagnosed by Capsule and Double-Balloon Endoscopy

We report the first case of small bowel ulcers due to clopidogrel in a 74-year-old man. He presented with diarrhea and melena after having been taking low-dose aspirin (LDA) and clopidogrel. There was no evidence of bleeding in the stomach, duodenum, or colon. Capsule endoscopy showed multiple ulcers and erosions in the small intestine. Double-balloon endoscopy revealed multiple ulcers throughout the ileum. Examination of the biopsy specimen showed cytomegalovirus infection. His LDA was discontinued and he was prescribed ganciclovir. However, the small bowel ulcers were aggravated. Therefore, clopidogrel was discontinued. The small bowel ulcers subsequently healed completely, forming scars

Thread-Traction with a Sheath of Polypectomy Snare Facilitates Endoscopic Submucosal Dissection of Early Gastric Cancers

Although the thread-traction (TT) method has been found useful during endoscopic submucosal dissection (ESD) for early gastric cancers, the movement of the thread interferes with the movement of the endoscope, and the lesion can only be pulled to the mouth side. We have developed the novel TT method using a sheath of polypectomy snare (TTSPS). The TTSPS method enables free and independent movement of the thread and the endoscope and allows pulling the lesion towards the anal as well as oral side. The median dissection times, numbers of instances of arterial bleeding, and numbers of local injections into the submucosal layer were significantly lower for ESD with TTSPS than for conventional ESD. Countertraction ESD using the TTSPS method is straightforward, safe, easy, noninvasive, and cost effective, and it uses instruments readily available in most hospitals to enhance visualization of cutting lines. Therefore, the TTSPS method can be universally applied in conventional ESD