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Magnetic-Amplifier Circuits Converting Half-Wave Input into Full-Wave Output with Transistor Switch
Get PDF論文(Article)電気的自動制御装置における磁気増巾器の実用化が進むにつれて，多段磁気増巾器として使用する場合も多くなった。多段磁気増巾器において全波若しくは交流の出力を得るには，初段，中間段，出力段各段共に鉄心を2個づつ用いて増巾を重ねる方法が，従来行われて来たが，初段，中間段においては，各段1個の鉄心を用いて半波増巾を重ね，出力段に至って全波若しくは交流に変換して出力を得るならば，種々の利点がある。即ち，各段毎に2個づつ特性の合った鉄心をえらび出して使用するという煩雑さもなく，回路構成も簡単になり，更に段間結合の容易なこと，過渡応答時間の縮少，初段及び中間段の消費電力の節減等を実現し得る許りでなく，特性も優れたものが得られる。 本稿はこの種の変換型磁気増巾器回路を考案し，その動作原理と共に，実験結果を示したものである。変換動作は，出力段主鉄心のゲートの際の磁束変化によって生ずる誘起電圧により，トランシスタを駆動し，これにより出力段従鉄心のリセット電流の点孤角を制御し，従鉄心にも主鉄心と同等のリセットを行わせて，全波若しくは交流の出力を得るものである。実験はブリッジ型全波出力及びダブラー型交流出力の双方の場合につき，種々の特性を測定し，又主，従両鉄心の磁束変化及び各部電流波形の制御経過中の変化を，特性曲線と対比しつつ，写真によって示し，又，従来の自己饋還型磁気増巾器との特性比較も行ってある。更に，出力電流及び各段制御電流を電磁オシログラフによって撮影し，過渡特性の吟味をも行った
ジアルキルエーテル類の電解酸化
Get PDF論文(Article)The anodic oxidation processes of dialkylethers in perchloric acid solution have been studied on the basis of analyses of products. The results obtained are as follows. (1) The main products are alcohol and aldehyde (or ketone) corresponding to carbon number of alkyl radicals consisting of the ethers One of the two alkyl radicals is oxidized to alcohol, another gives aldehyde. (2) The oxidation processes are the reaction via α-cation of the ethers formed by two electron transfer and deprotonation in α-position, and then alkyl cation may be considered to be formed through the α-cation. (3) In the case of unsymmetrical dialkylethers, the deprotonation occurs in methyl radical if one of two alkyl radicals is methyl radical. The deprotonation in ethylbutylether, however, is observed in both two alkyl radicals, but it is easy to occur in ethyl radical having a minor carbon number
長さの異なる線路とコンデンサからなる回路の一合成法
Get PDF論文(Article)The paper deals with a synthesis of multivariable circuits which are composed of noncommensurate transmissio lines and lumped capacitors, in order to obtain a filter being compact and having physically rea1izable circuit elements The variable of transmission line is the variable q q = p/α p = jtan (πf/2f_0) α= |P|_(f=fc) = tan (πf_c/2f_0) where Richards' variable p is normalized by the absolute value α of Richards' variable at the cut off frequeney f_c, f_0 is the frequency at which line length l becomes equal to a quarter wave length. Design examples of low pass filter with lumped-distributed elements and synthesis examples of ladder-type networks consisting of transmission lines, whose characteristic immitances are the same, are described. In the latter, each element of lumped ladder network is replaced by corresponding transmission line respectively, whose charatcteristic immitance is identified, but whose line iength is variable
神経系培養細胞におけるα―シヌクレインSer129のリン酸化反応の寄与する酵素の同定およびリン酸化α―シヌクレインの生理機能の解析：パーキンソン病の病態への関与について
Get PDF学位論文(Thesis)論文内容要旨学位取得大学:山形大学 ; 報告番号:生医科博甲第15号 ; 学位の種類: 課程 ; 学位の種別:博士(医科学
Podocalyxin expression in malignant astrocytic tumors
Get PDF学位論文(Thesis)論文内容要旨学位取得大学:山形大学 ; 報告番号:医博乙第557号 ; 学位の種類: 論文 ; 学位の種別:博士(医学
Preoperative pentraxin 3 concentration in pericardial fluid is related to adverse out comes in patients undergoing cardiac surgery
Get PDF学位論文(Thesis)論文内容要旨学位取得大学:山形大学 ; 報告番号:医博乙第554号 ; 学位の種類: 論文 ; 学位の種別:博士(医学
27項目の看護ケア技術に関するイノベーション普及過程と関連要因の分析
Get PDF学位論文(Thesis)学位授与大学:山形大学 ; 学位記番号:第4号 ; 学位の種類:看護 ; 学位の種別:修士 ; 学位授与年月日:1999年3月31
心臓電気現象の3次元コンピュータシミュレーション : 心筋梗塞、心不全における不整脈発生機序の解明
Get PDF論文(Article)背景：心疾患に伴う不整脈死は重要な社会的課題であるが、不整脈の発生機序はいまだ解明されていない。そこで心臓の電気現象をコンピュータ上に再現し、モデル心臓を再構築することで心臓のさまざまな電気現象の機序を解明しようと試みた。 方法：ユニット分割３次元モデル心臓上で心筋梗塞・心不全の条件を設定し、不整脈発生をシミュレートした。 心臓モデルは心房筋、心室筋、特殊伝導系を含む1.5mm^3 の等方向伝播の分割ユニット約50,000個から構成した。心筋梗塞は既知の条件(線維化組織の無興奮と周囲組織の伝導遅延)、心不全は実験的心不全から実測して条件を求めた。このモデル心臓に対して、仮想の電気的刺激を加えることで不整脈の発生機序を検討した。 結果：梗塞周囲に興奮伝導遅延部位を設定することで心室遅延電位が発生し、かつ心室細動の易誘発性が認められた。また心不全では様々なパラメータが変動するが、特にdynamic coefficientの変動が不整脈の発生に直接的に関係した。 結論：以上の結果はそれぞれの疾患の不整脈発生機序に深く関係するもので不整脈対策立案上、重要な所見である。 キーワード：コンピュータ、シミュレーション、心筋梗塞、心不全 Background : The precise mechanism of ventricular arrhythmia is still unclear. The simulation study using the 3-dimential heart model may help us increase the understanding of this issue. Methods : A model heart was constructed of 50,000 discrete elements with 1.5 mm spatial resolution. Each element was a simulation of myocytes or conduction system, and was categorized with features of action potential, conduction velocity and automaticity in each model cell. Results : Simulation of myocardial infarction revealed that the presence of peri-infarctional slow conduction and Purkinje fibers was essential for the induction of VF. Simulation of failing heart revealed that the alteration of restitution properties was essential for the induction of VF. Conclusion : The present simulation studies provided important information about the mechanism of ventricular arrhythmia. Key words : computer, simulation, heart failure, myocardial infarctio
Mechanism of Interleukin 2-Induced Signal Transduction
Get PDF論文(Article)Extensive studies on the IL-2 and IL-2 receptor system have established fundamental principles of immune responses and signal transducing mechanisms of hematopoietic cell proliferation and survival. IL-2Rb and IL-2Rg chains are associated with multiple tyrosine kinases including JAK1, JAK3 and other tyrosine kinases such a p56lck. IL-2 binding to these receptors leads to conformational changes of the receptors followed by the recruitment of several kinases leading to their activation. The JAKs and activated tyrosine kinases appear to be a trigger for the downstream signal cascades. Other downstream messenger molecules such as the STATs, Shc, PI3K-Akt, Ras-ERK1/2 and so on, cross talk with this cascades. The interplay however leading to the regulation of target genes still remain largely obscure. For example, although phosphorylation of tyrosine 338 of IL-2Rb is required for both signal transduction to Shc and PI3K, how it regulates further signals from Shc to the Grb2-Sos-Ras pathway or to the PI3K-Akt pathway is unknown. There are also conflicting reports on the functional roles of STAT5, STAT1 and STAT3 on IL-2 signaling. Further work is needed to clarify how the multiple kinases trigger multiple signaling cascades and cooperate with each other in the regulation of gene induction for cell growth, survival or differentiation in different cell types and conditions in vitro and also in vivo. Key words : IL-2, tyrosine kinase, signal transduction, cytokin
Temporary Hyperbilirubinemia in Two Patients During Treatment for Idiopathic Nephrotic Syndrome
Get PDF論文(Article)We present two patients with idiopathic nephrotic syndrome who showed temporary indirect hyperbilirubinemia during the course of treatment with immunosuppressant drugs and/or steroids. We analyzed the gene of the bilirubin uridine-diphosphate glucuronosyltransferase (B-UGT) and found that patient 1 was a compound heterozygote for the G71R and T-3263G mutations and patient 2 was a heterozygote for the G71R mutation. Hyperbilirubinemia should be considered as one of the adverse effects of immunosuppressant drugs and/or steroids in patients carrying the polymorphic mutations of the B-UGT gene. Key words : nephrotic syndrome, bilirubin uridine-diphosphate glucuronosyltransferase, hyperbilirubinemi