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Background: The energy distribution of excited states populated by the nuclear muon capture reaction can facilitate an understanding of the reaction mechanism; however, experimental data are fairly sparse. Purpose: We developed a new methodology, called the in-beam activation method, to measure the production probability of residual nuclei by muon capture. For the first application of the new method, we have measured muon-induced activation of five isotopically-enriched palladium targets. Methods: The experiment was conducted at the RIKEN-RAL muon facility of the Rutherford Appleton Facility in the UK. The pulsed muon beam impinged on the palladium targets and gamma rays from the beta and isomeric decays from the reaction residues were measured using high-purity germanium detectors in both the in-beam and offline setups. Results: The production branching ratios of the residual nuclei of muon capture for five palladium isotopes with mass numbers A = 104, 105, 106, 108, and 110 were obtained. The results were compared with a model calculation using the particle and heavy ion transport system (PHITS) code. The model calculation well reproduces the experimental data. Conclusion: For the first time, this study provides experimental data on the distribution of production branching ratios without any theoretical estimation or assumptions in the interpretation of the data analysis, 20 pages, 11 figures

Background: The nuclear charge radius and distribution are the most fundamental quantities of the atomic nucleus. From the muonic transition energies, the absolute charge radius has been experimentally obtained, while there have been no established methods to discuss the distribution. Purpose: The muonic transition energies for five palladium isotopes with the mass number $A = 104$, $105$, $106$, $108$ and $110$ were measured. The procedure to deduce the charge radii and the method to discuss the charge distribution from the muonic transition energies are proposed. Method: The experiment was performed at the MuSIC-M1 beamline at Research Center for Nuclear Physics, Osaka University. A continuous muon beam impinged on the enriched palladium targets. Muonic X rays were measured by high-purity germanium detectors. Results: The muonic transition energies up to $4f$-$3d$ transitions were determined for five palladium isotopes. Discussion and conclusion: The root-mean-square charge radii are deduced assuming the two-parameter Fermi distribution. The charge distribution of the nucleus is discussed employing the Barrett model. The muonic transition energies of the $3d$-$2p$ transitions are crucial to discuss both the charge radius and the charge distribution.

Production cross sections of residual nuclei via proton-and deuteron-induced spallation reactions on 91,92 Y, 92,93 Zr, and 93,94 Nb at projectile energies Production cross sections of residual nuclei via proton-and deuteron-induced spallation reactions on $^{91,92}$Y,$^{92,93}$Zr,and $^{93,94}$Nb at projectile energies around 100 MeV/nucleon were measured in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Noticeable jumps in the measured cross sections of isotone production appear between the neutron numbers N =51 and 50 for target nuclei with the initial neutron number N$_{init}$ =53 ($^{92}$Y, $^{93}$Zr, and $^{94}$Nb), while such jump is not clearly seen for target nuclei with N$^{init}$=52($^{91}$Y,$^{92}$Zr, and $^{93}$Nb). The measured isotopic production cross sections are compared with PHITS calculations considering both the intranuclear cascade and evaporation processes in order to benchmark the reaction models.

Excited configurations of hydrogen in the oxyhydride BaTiO$_{3-x}$H$_x$ ($x=0.1-0.5$), which are considered to be involved in its hydrogen transport and exchange processes, were investigated by positive muon spin relaxation ($\mu^+$SR) spectroscopy using muonium (Mu) as a pseudoisotope of hydrogen. Muons implanted into the BaTiO$_{3-x}$H$_x$ perovskite lattice were mainly found in two qualitatively different metastable states. One was assigned to a highly mobile interstitial protonic state, which is commonly observed in perovskite oxides. The other was found to form an entangled two spin-$\frac{1}{2}$ system with the nuclear spin of an H$^-$ ion at the anion site. The structure of the (H,Mu) complex agrees well with that of a neutralized center containing two H$^-$ ions at a doubly charged oxygen vacancy, which was predicted to form in the SrTiO$_{3-\delta}$ perovskite lattice by a computational study [Y. Iwazaki $et$ $al$., APL Materials 2, 012103 (2014)]. Above 100 K, interstitial Mu$^+$ diffusion and retrapping to a deep defect were observed, which could be a rate-limiting step of macroscopic Mu/H transport in the BaTiO$_{3-x}$H$_x$ lattice., Comment: 5 pages, 4 figures

[概要] 音楽は18-19世紀にその最高の高みに達したとよくいわれる. その原動力の一つは, 音楽の作曲の堅牢さにあるといえる. その点, 数学の堅牢さと通ずるものがある. ゲーテの言葉を借りれば, 幾何学は凍れる音楽である, となる. ここで幾何学は数学にまで拡大される. それは, 中世ヨーロッパの大学の高等教育で教えられていたのは７科目であり, そのうち３科目は, 文法, 論理学, 修辞法であった. この３=triからtrivial（自明）ということばが派生した. 数論, 幾何学, 天文学, 音楽の４科目はより高等なものとして扱われ, quadriviaとよばれていた. ゲーテにとって幾何学=数学であったと思われる. 音楽と数学のこの密接な関係に鑑みて, 両者をつなぐ新理論の展開の場である関数空間を模索した結果, 有限パワー信号（関数）の空間ではないかと考えるに至った. 本論文はこれまで本セミナーシリーズで展開してきたフーリエ変換理論の頂点であり, 生き物と死に物の境界に位置する対象研究の魁である.

[概要] 本論文は、月一回開催している学際セミナーのとくに、2012年度第14回、第15回セミナーで取り上げた「Elucidation and generalization of the Cooley-TUkey algorithm-CTA」において展開した、離散フーリエ変換の計算量を低減するアルゴリズムであるCTAを、群の表現を用いるダイアコーニス等の方法を用いて明らかにし、合わせて群とその表現(とくに群行列)の基礎を述べたものである。本セミナーの目的の一つである、大学教育における新たな教科書を作成する大いなる一歩であると確信している。本論文では、アーベル群の場合をのみを扱っているが、目標は、アウスランダー等の行った、冪零群の場合の非アーベル的フーリエ変換の計算量の低減を目標とする。ダイアコーニスの場合は、表現を付随させたベクトル値関数であり、ヴェンコフの場合のスペクトル理論の精神と類似しており、将来表現論的保型形式の研究にも通ずると信ずる。 [Abstract] In this paper, we shall elucidate the celebrated Cooley-Tukey (Cool and Tacky) algorithm [4] from representation-theoretic view point, following [6] in general and [1] in the case of nilpotent groups. We are concerned with non-Abelian Fourier transforms, which have many applications including one of the symmetric groups to statistics. Considering the Fourier transform with vector-valued function is rather efficient and can be studied together with Venkov's theory of automorphic forms with representations [17], [18], to be pursued subsequently. We shall also give some preliminaries on groups, linear representation of groups and group matrices.

[概要] 本論文は、筆者らが月1回開催している学際的なセミナーにおいて工学分野におけるディラックのデルタ関数の使用の正当性について論じたものである。本セミナーはこれまでに12回実施しており、工学領域における数学的基盤の見直しなどを試みることにより、大学教育における新たな教科書作成を目標としている。これまで議論してきた、自動制御システム、マン・マシンシステム、離散フーリエ変換、符号理論、コード化とシフトレジスタ合成の線形再帰系列については別稿で報告している。本稿は第12回の内容についてまとめたものである。

[概要] 本論文は,月一回開催している学際セミナーのとくに, 第3回離散フーリエ変換, 第4回符号理論の議論の中から自然に発生してきた線形回帰式の理論を, ピンシェルレ双対性のもとで, 対応する微分方程式のラプラス変換による解法とパラレルな解法--オペレーターによる解法として述べたものである. 本セミナーの目的の一つである, 大学教育における新たな教科書を作成する大いなる一歩である. 上記ピンシェルレ双対性の概念に至るには, 第1, 2節で述べるブラハット定理のマッシーによる, LFSRを用いた定式化が根底に存し, LFSRはフィードバックシステムの一種であるから, 当然第2回セミナーの制御系からの発想もあずかっている. 別途出版予定の論文で, 巡回符号におけるLFSRを, FDEの問題と認識することによって, FDE, それとピンシェルレ双対であるODEの解法, それの金光--塚田による部分分分数分解をフルに用いる方法, さらに差分方程式に関する興味深いいくつかの結果を付け加えた. [Abstract] In our previous report, we have collected the records of the 2nd and the 3rd seminars. There is a report of the 7th seminar which will not be published as it is but is expected to get expanded to be published as a new paper.

The effect of the H2-receptor antagonists cimetidine and famotidine on interdigestive gastric motor activity and lower esophageal sphincter pressure was assessed in 41 patients with uncomplicated progressive systemic sclerosis. There was no significant change in gastric phasic motor activity after the intravenous administration of cimetidine (n=6), famotidine (n=13), and physiological saline (n=15), or the intragastric infusion of 7% sodium bicarbonate (n=7). The lower esophageal sphincter pressure was increased significantly by both cimetidine and famotidine, but only famotidine caused a significant pressure rise in patients without an increase of gastric motility. Cimetidine and physiological saline produced a similar pattern of change in the esophageal sphincter pressure, as did famotidine and sodium bicarbonate. These findings suggest that the inhibition of acetylcholinesterase activity and gastric acid secretion may be involved in the respective mechanisms of action of cimetidine and famotidine.(Internal Medicine 33: 407-412, 1994)

Recent studies have suggested that intrauterine undernutrition is closely associated with the pathogenesis of diseases after birth. Perinatal undernutrition is known to disturb the development of reproductive function and delay the onset of puberty in some species. Using a rat model, we determined the effects of prenatal undernutrition on the development of the hypothalamic kisspeptin system and evaluated whether the alteration of the kisspeptin system contributes to the delayed onset of puberty induced by prenatal undernutrition. We also evaluated the effects of prenatal undernutrition on the developmental changes in serum leptin levels because leptin was a putative positive regulator of the hypothalamic kisspeptin system. We compared the timing of vaginal opening (VO) and the developmental changes in body weight, hypothalamic Kiss1 mRNA levels, and serum leptin concentrations between offspring with prenatal undernutrition (UN offspring) and normal nutrition (NN offspring). After birth, the UN offspring showed rapid growth and had caught up to body weight of the NN offspring by postnatal day 12. After postnatal day 16, the UN offspring showed significantly lower Kiss1 mRNA levels than the NN offspring, despite their significantly higher serum leptin levels (at days 20 and 28). The timing of VO in the UN offspring was delayed compared with that in the NN offspring, and chronic central injection of kisspeptin normalized the timing of VO in the UN offspring. These results suggest that decreased hypothalamic kisspeptin action contributes to the delayed onset of puberty in prenatally undernourished female rats. Increased leptin resistance in the kisspeptin system might be involved in these alterations.

The clinical efficacy and safety of lansoprazole, administered in a dose of 30mg once daily after breakfast, were studied in an open trial with 38 patients with erosive/ulcerative reflux oesophagitis. In 3 of these patients, the effect on gastro-oesophageal reflux and gastroduodenal motility was also investigated by 24-hour pH and motility monitoring, performed before and 1 week after starting lansoprazole therapy.

The effects of famotidine on human upper gastrointestinal motility were investigated, together with the relationship of gastric alkalinization and serum gastrin levels to changes produced by famotidine. Intravenous famotidine (20 mg), at a dose level in which an inhibitory effect on acetylcholinesterase activity is not recognized, was given to 13 patients with progressive systemic sclerosis but no other disorders. Gastric phasic motor activity was not changed significantly, but the lower esophageal sphincter pressure was elevated significantly in comparison with 15 controls given physiological saline, even when gastric phasic motor activity was taken into consideration. Gastric alkalinization with 7% sodium bicarbonate did not significantly increase the sphincter pressure in all 7 subjects so treated. No significant correlation was recognized between the serum gastrin level, the lower esophageal sphincter pressure, and the gastric motility index in any of the 3 groups. It was, therefore, concluded that intravenous administration of famotidine affected upper gastrointestinal motility, especially the lower esophageal sphincter pressure, through an as yet unknown mechanism other than inhibition of acetylcholinesterase activity, gastric alkalinization, or elevation of serum gastrin levels.

The advent of histamine H2 receptor antagonists (H2-RA) has allowed the treatment of reflux esophagitis (RE) to be controlled over a relatively long term. The authors have experienced some cases resistant to H2-RA, but it was revealed that these cases can be successfully treated with proton pump inhibitors. It has been suggested that esophagogastric dysmotility can lead to RE. RE has been treated for many years by using GI-prokinetic agents, which theoretically inhibit acid reflux and improve esophageal acid clearance. In order to compare the effects on acid reflux of an H2-RA (famotidine), a proton pump inhibitor (omeprazole) and a GI-prokinetic agent (cisapride), we measured the 24-hour pH in the esophagus and stomach simultaneously, before and after treatment in 17 patients with RE. It was found that the proton pump inhibitor was the most effective drug for inhibiting esophageal acidification, followed by famotidine and then cisapride. Furthermore, we found that cisapride often actually exacerbated acid reflux. The differences in inhibitory effects on acidification allowed us to draw conclusions regarding the treatment of RE. It was concluded that the stronger the inhibitory effect of a drug on acid secretion, the more useful it was in the treatment of RE. The GI-prokinetic drug did not inhibit acid reflux as much as we had expected.

The relationship between interdigestive gallbladder and gastroduodenal motility simultaneously with the behavior of plasma motilin and CCK levels in 20 subjects was investigated. We used an infusion catheter method for the measurement of gastroduodenal motility, and real-time ultrasonography for the measurement of gallbladder size. In gastric phase II, the gallbladder contracted with extension of the major axis and shrinking of the minor axis, with its minimum volume being 84% of the volume in phase I. The gallbladder then filled rapidly assuming a sphere-like shape with extension of the minor axis and shrinking of the major axis in gastric phase I. This motility was recognized only during the gastrointestinal interdigestive migrating complex (GI-IMC) cycle, originating in the stomach, and was associated with an increase of motilin levels, it was not seen before or after the intestinal IMC (I-IMC), which originated in the duodenum without contraction of the stomach or an increase of motilin levels. Furthermore no apparent relationship was recognized between CCK and gastric or gallbladder motility. Our findings suggest that gallbladder motility in the interdigestive period has a close relationship with gastroduodenal motility and is related to the appearance of the GI-IMC.

The clinical usefulness of 150mg roxatidine acetate hydrochloride once daily before bed in 20 patients with reflux oesophagitis was investigated in a double-blind trial, comparing treatment with 75mg twice daily (after breakfast and before bedtime in 22 patients).

In recent years, interfacial fracture becomes one of the most important problems in the assessment of reliability of electronics packaging. Especially, underfill resin is used with solder joints in flip chip packaging for preventing the thermal fatigue fracture in solder joints. In general, the interfacial strength has been evaluated on the basis of interfacial fracture mechanics concept. However, as the size of devices decrease, it is difficult to evaluate the interfacial strength quantitatively. Most of researches in the interfacial fracture were conducted on the basis of the assumption of the perfectly bonding condition though the interface has the micro-scale structure and the bonding is often imperfect. In this study, the mechanical model of the interfacial structure of resin in electronic components was proposed. Bimaterial model with the imperfect bonding condition was examined by using a finite element analysis (FEA). Stress field in the vicinity of interface depends on the interfacial structure with the imperfect bonding. In the front of interfacial crack tip, the behavior of process zone is affected by interfacial structure. However, the instability of fracture for macroscopic crack which means the fracture toughness is governed by the stress intensity factor based on the fracture mechanics concept., Comment: Submitted on behalf of TIMA Editions (http://irevues.inist.fr/tima-editions)

Fourteen patients with duodenal ulcers and eight healthy volunteers were examined to measure interdigestive gastroduodenal motility and plasma motilin. In order to study the effects of gastric acid on the gastroduodenal motility, 20 mg of famotidine was administered intravenously. The motility index of the gastric antrum and the duodenum, as well as the pH in the duodenal bulb were calculated. The duodenal pH was significantly lower and the gastric motility index was significantly weaker before the duodenal interdigestive migrating complex (IMC) in the ulcer patients than in the controls. Motilin levels increased before the duodenal IMC and decreased afterwards in both groups. Famotidine significantly increased the duodenal pH and the gastric motility index before the IMC, but no changes in the motilin level were noted. We conclude that duodenal ulcer patients have duodenal hyperacidity that results from increased inflow from the antrum and antral hypomotility during the gastric IMC and that these changes are normalized by the administration of famotidine. These results suggest that gastric acid inhibits antral contraction during the gastric IMC.

The 24-hr gastric and duodenal pressure measurement was performed in 5 patients with non-ulcer dyspepsia (NUD). The reduction of incidence of IMC and prolongation of the first appearance of IMC after evening meal were observed in NUD patients. The gastroprokinetic agent, cisapride 5 mg, 3 times a day for 7 days significantly increased the incidence of IMC and shortened the time before the first appearance of IMC after evening meal. This result indicates that in NUD patients impaired gastrointestinal motility is present in fasting phases and cisapride may be useful for correcting motility disorders.

CT上脳卒中発作の責任病巣とみなされた低吸収域を基底核に認めた症例は, 脳梗塞223例中95例42.4%に相当する. 本研究の対象とした症例は, 95例中脳血管写を実施しえた65例で, その内訳は脳梗塞60例, 一過性脳虚血発作 (以下TIAと略す) 5例である. 基底核小梗塞の臨床症状を明らかにするとともに, 内頚動脈や中大脳動脈などの主幹動脈閉塞症例とも比較した. 基底核小梗塞は主幹動脈閉塞例に比べ睡眠中に発症する頻度は少ない傾向を示すとともに, 神経症状は2～3日以内に進展完了しており, 主幹動脈閉塞例のように段階的に発作を繰返す症例はなかった. 片麻痺では, 完全麻痺を示したものは僅か3.3%に過ぎず, また上肢と下肢の麻痺程度が同じか, 上肢が下肢より強い例が多く, 下肢が上肢より麻痺が強い例は8.3%に過ぎない. 片麻痺の程度は内包後脚の中央より後方の障害において, 他の部分よりも強かった. また麻痺の改善度は, 部位よりも病巣の大きさによって異り, 病巣の大きさが10mm未満の方が10～15mmの症例よりも,麻痺の改善度が良好であった. また知覚障害を伴わない所謂 pure motor hemiplegia が約半数近くに認められた. つぎに基底核小梗塞は主幹動脈閉塞例に比べ, 最小血圧において, やや高い傾向を示し, また血清脂質においては, 総コレステロール値, β-リポ蛋白値は, 主幹動脈閉塞例に比べやや低値を示すものが多かった. 脳血管所見としては, ほとんど異常所見のなかった症例が60%に認められたことは注目すべきことと考える. またTIAと基底核小梗塞との関連をみると, TIAの既往を有する率は他の型の脳梗塞に比べ, 基底核小梗塞に多い. しかも発作前1日以内にTIAをもつ症例が多く, 同じ片麻痺のパターンを示したことは興味深い. CT上基底核低吸収域を認めたTIAは5例であったが, そのうち2例に発作後14～17日で contrast enhancement を行い陽性像を示し, TIAの責任病巣と考えた.