On Isogeny Characters of Drinfeld Modules of Rank Two

ファイルを差し替え（2021/12/16）In this paper, we study cyclic torsion subgroups of Drinfeld Fq[T]- modules of rank two over Fq(T) via isogeny characters associated to them. Among other things, we prove that such Drinfeld Fq[T]-modules do not have a cyclic p-torsion subgroup defined over Fq(T) under various conditions, where p is a maximal ideal of Fq[T]. We also obtain some unconditional results

通常素数に対する一点抜き虚数乗法付き楕円曲線に付随する副p外Galois表現の研究

京都大学新制・課程博士博士(理学)甲第24389号理博第4888号新制||理||1699(附属図書館)京都大学大学院理学研究科数学・数理解析専攻(主査)教授 玉川 安騎男, 教授 並河 良典, 教授 望月 新一学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDGA

Incisional atrial reentrant tachycardia: experimental study on the conduction property through the isthmus

AbstractBackgroundIncisional atrial reentrant tachycardia is a life-threatening tachyarrhythmia after surgery for congenital heart disease. Slow conduction through an isthmus between anatomical barriers, such as a right atriotomy or the sites for cannulation, has been shown to be a prerequisite for perpetuation of the incisional atrial reentrant tachycardia. However, the conduction property through the isthmus has not been examined in detail.MethodsTo examine the conduction property, 2 tandem incisions were made on the lateral right atrium with various distances (3 to 20 mm) between the incisions in 16 canines. Four weeks after the surgery, the lateral right atrium was mapped epicardially during pacing to examine the conduction property through the isthmus. The conduction property was characterized by approximated curves of the conduction velocity through the isthmus in accordance with the pacing cycle lengths. The atrial tissue at the isthmus was examined microscopically.ResultsThe approximated curves of the conduction velocity were classified into 3 different types. Decremental conduction was observed only in the isthmi between 5 and 15 mm in width. A small amount of surviving myocardium between the scars formed the critical isthmus microscopically (decremental type). In the isthmi wider than 15 mm in width, slow conduction was not seen at any paced cycle length (nondecremental type). In the extremely narrow isthmi less than 5 mm in width, all of the atrial myocardium at the isthmus was replaced by fibrous tissue. Conduction was blocked at the isthmus and the activation detoured around the incisions (block type). There was a statistically significant difference in the approximated curves between the 3 different types of conduction properties (P < .01).ConclusionThe width of the isthmus determines the conduction property through the isthmus that contributes to the development of the incisional atrial reentrant tachycardia. Thus, the incisional atrial reentrant tachycardia may be preventable by leaving a sufficient amount of surviving myocardium between the incisions or by connecting the incisions by an ablative procedure