1,329 research outputs found
Numerical Simulation in Ulcer-Like Projection due to Type B Aortic Dissection with Complete Thrombosis Type
Thermal Molecular Motion Can Amplify Intermolecular Magnetic Interactions
Against a sensible expectation that molecular mobility in fluids generally disrupts magnetic orderings that depend on intermolecular interactions, some molecular compounds with isolated electrons, which are called radicals, exhibit the increase of magnetic susceptibility in melting. Here we first propose a simple model to explain the thermomagnetic anomaly unique to fluids; the effect of the magnetic interactions in each of the contacts could be accumulated on each of the molecular spins as if the molecular motion amplified the first coordination number of each molecule hundredfold. The huge coordination number theoretically guarantees the retention of memory of interactions at equilibrium; molecules might be able to conserve the memory of molecular conformations, configurations, electric charges, energies as well as magnetic memory with each other.Yoshiaki Uchida, Go Watanabe, Takuya Akita et al. Thermal Molecular Motion Can Amplify Intermolecular Magnetic Interactions, The Journal of Physical Chemistry B 124 (28), 6175-6180, July 16, ©2020 American Chemical Society. https://doi.org/10.1021/acs.jpcb.0c0540
Risk factor analysis of thoracic endovascular repair using the Matsui-Kitamura stent graft for acute aortic emergencies in the descending thoracic aorta
ObjectiveIn recent years, thoracic endovascular aneurysm repair (TEVAR) has been attempted for acute aortic emergencies (AAEs). However, the risk factors for achieving good results have not been identified. Besides focusing on Acute Physiology and Chronic Health Evaluation (APACHE) II score as a general indicator of patient condition, we analyzed both preoperative factors and intraoperative/postoperative factors. The purpose of this study was to identify those factors affecting the results of TEVAR using our Matsui-Kitamura stent graft (MKSG) for AAEs involving descending thoracic aortic aneurysm.MethodsBetween July 2000 and June 2008, a total of 32 patients (23 men, 9 women) with AAEs underwent endovascular repair. AAE was a result of aortic aneurysm rupture in 16 cases, rupture of penetrating atherosclerotic ulcer in 2 cases, traumatic aortic injury in 9 cases, complicated type B dissection in 4 cases, and aortic infiltration of sarcoma in 1 case. Low blood pressure in 6 patients, acute renal failure in 7 patients, anemia due to bleeding in 12 patients were found at the time of operation. Urgent TEVAR using the MKSG was performed. Perioperative and long-term results for these patients were investigated.ResultsThe delivery and technical success rate for TEVAR using the MKSG, was 100%. Perioperative mortality was 12.5%, and 5-year survival rate was 71%. In both univariate and multivariate analysis, the APACHE II score clarified a risk factor. Among the various elements of an APACHE II score, age, hematocrit, and total score were identified as significant factors. The mean of an APACHE II score was 9.5. Patients with an APACHE II score ≥10 showed significantly lower 5-year survival rates than patients with an APACHE II score ≤9.ConclusionsGood results were obtained using TEVAR to treat AAEs with MKSGs, both perioperatively and during medium-term follow-up. Evaluation of risk factors for TEVAR of AAEs showed the utility of APACHE II score (particularly age, hematocrit, and total score) with a score ≥10 indicating high risk
A Training Method for the Speech Controlled Environmental Control System Based on Candidate Word Discriminations
This paper proposes a concept of a training system for the speech controlled environmental control system: Bio-Remote based on candidate word discriminations. The proposed system can provide three-types of voice signal training: (1) volume, (2) tempo/timing and (3) candidate word which are important for accurate speech recognition based on false recognition results. During the training, such three kinds of features are extracted from measured voice signals and visually and auditory fed back to the user in real time. This allows the user to train speech abilities even if false recognition results are extracted because of slurred speech. The efficacy of the proposed system was demonstrated through training experiments for slurred speech conducted with healthy participants. The results showed that the proposed system was capable for the training of speech abilities.This work was partially supported by JSPS/MEXT KAKENHI Grant Numbers 17K12723 and 26330226
Development, implementation and acceptance of an AI-based tutoring system. A research-led methodology
This Design-Based Research (DBR) project aims to develop an intelligent tutoring system (ITS) for higher education. The system will collect teaching and learning materials in audio and video formats (e.g., podcasts, lecture recordings, screencasts, and explainer videos), and store them on a learning experience platform (LXP). Then, the ITS will process them with the help of speech recognition to gain data which, in turn, will be used to power further applications: Using artificial intelligence (AI), the platform will allow users to search the materials, automatically compiling them according to criteria like lesson subject, language, medium, or required prior knowledge. By the end of the last DBR cycle, the ITS will also provide a more active form of support: It will automatically generate exercises based on predefined patterns and teaching materials, thus allowing learners to check up on their learning progress autonomously. In order to closely match the ITS’s features to the needs and learning habits of students in higher education, the development of this AI-based tutoring system is accompanied by an interdisciplinary team which will continuously re-evaluate and adapt the concept over the course of several DBR cycles. Our goal is to derive implications for the system’s technical development by collecting and evaluating educational research data (mixed methods design; primary and secondary research methods). (DIPF/Orig.)Dieses Design-Based Research (DBR)-Projekt zielt auf die Entwicklung eines intelligenten Tutorensystems (ITS) für die Hochschulbildung ab. Das System wird Lehr- und Lernmaterialien in Audio- und Videoformaten (z.B. Podcasts, Vorlesungsaufzeichnungen, Screencasts und Erklärvideos) sammeln und auf einer Learning Experience Platform (LXP) speichern. Anschließend wird der ITS sie mit Hilfe von Spracherkennung verarbeiten, um Daten zu gewinnen, die wiederum für weitere Anwendungen genutzt werden können: Mithilfe von künstlicher Intelligenz (KI) wird die Plattform es den Nutzern ermöglichen, die Materialien zu durchsuchen und sie automatisch nach Kriterien wie Unterrichtsthema, Sprache, Medium oder erforderlichen Vorkenntnissen zusammenzustellen. Am Ende des letzten DBR-Zyklus wird der ITS auch eine aktivere Form der Unterstützung bieten: Er wird automatisch Übungen auf der Grundlage von vordefinierten Mustern und Lehrmaterialien erstellen, so dass die Lernenden ihre Lernfortschritte selbständig überprüfen können. Um die Eigenschaften des ITS genau auf die Bedürfnisse und Lerngewohnheiten der Studierenden im Hochschulbereich abzustimmen, wird die Entwicklung dieses KI-basierten Tutorsystems von einem interdisziplinären Team begleitet, das das Konzept über mehrere DBR-Zyklen hinweg kontinuierlich neu evaluiert und anpasst. Unser Ziel ist es, durch die Erhebung und Auswertung von Daten aus der Bildungsforschung (Mixed-Methods-Design; Primär- und Sekundärforschung) Implikationen für die technische Entwicklung des Systems abzuleiten. (Autor
Bilateral minimally invasive direct coronary artery bypass grafting with the use of two arterial grafts
覚醒下冠動脈バイパス術に関する基礎的ならびに臨床的研究
基礎研究平成16年の動物実験にて胸部交感神経(Th1-Th5)を切除した交感神経ブロックモデルにおいて,冠血流増加作用と心筋虚血耐性作用を確認した.臨床研究(1)高位硬膜外麻酔(TEA群)と全身麻酔(GA群)による冠動脈バイパス術における術中,術後の自律神経解析では,LF(交感神経の指標)はTEA群で有意に抑制され,HF(副交感神経の指標)はTEA群がGA群に比べ有意に活動性が高い事が解った.また不整脈の発生はTEA群で有意に少なく,TEAは交感神経を抑制し,不整脈の発生を減少させることが確認し論文報告した.(2)TEAによる頭蓋内の血流,酸素飽和度測定を行い.TEA群ではGA群に比べ血圧低下に伴うカテコールアミン投与量が少量であり,その結果血圧60以下となるようなAuto regulationから逸脱する症例が軽減され,結果として術中脳血流が安定することが判明した.(3)高位硬膜外麻酔によるAwake OPCABの臨床例60例を経験し,全身麻酔のみの冠動脈バイパス術に比べ術後回復が有意に早く,入院期間も短いことを報告した.(4)Awake OPCAB20例と全身麻酔のみの冠動脈バイパス術症例20例ずつにおいて,Mini-mental State Examination(MMSE) TestとBenton Visual Retention Testを術前,術後3日目,術後7日目に施行した.全身麻酔群で術後3日目において両テストともに有意に低い値を示し,局所麻酔によるAwake OPCABは全身麻酔によるCABGに比べ高次脳機能が維持されることが確認された.Basic researchIn 2004,we evaluated the effects of thoracic epidural anesthesia (TEA) to the coronary blood flow and the augmentation of tolerance for myocardial ischemia in acute myocardial models with rats.Results of this study presented that TEA increased the coronary blood flow and decreased the area of myocardial infarction after the coronary artery occlusion.Clinical research1)We reported thoracic epidural anesthesia (TEA) inhibited the activation of sympathetic nerve strongly compared to general anesthesia and furthermore TEA reduced arrhythmia during CABG.2)We monitored the brain blood flows and the O2 saturation during off-pump CABG(OPCAB). The TEA stabilized the brain blood flow more than general anesthesia by avoiding the low blood pressure during the anastomosis.3)We reported 60 awake off pump CABG (AOCAB) by using TEA. The patients with AOCAB recovered faster than them of OPCAB with general anesthesia.4)We studied Mini-mental State Examination (MMSE) and Benton Visual Retention Test to the 20 patients with AOCAB and 20 with standard general anesthesia OPCAB. This study resulted AOCAB maintained higher level function of brain.研究課題/領域番号:16390392, 研究期間(年度):2004-2005出典:「覚醒下冠動脈バイパス術に関する基礎的ならびに臨床的研究」研究成果報告書 課題番号16390392 (KAKEN:科学研究費助成事業データベース(国立情報学研究所)) 本文データは著者版報告書より作
超音波CCDカメラを用いた完全鏡視下心腔内・大血管内手術systemの開発
金沢大学医学系研究科1.横方向の観察が可能な血管内視鏡の開発【対象と方法】食用ブタをもちいた.先端角可変式の血管内視鏡に改良を加えた.先端にウレタン製のバルーンを装着し,working channelからCO2を送気した.視野の確保,耐圧性,血栓症等の発生を検討した.【結果】本実験では150mmHgまでの圧に対してもバルーンの破損は来さなかった.満足すべき視野が得られた.バルーン拡張により心腔内・大動脈内の明らかな損傷を来さなかった.血栓症等の合併症は認められなかった.2.カテーテル型吻合装置の開発:血管吻合器と内視鏡下治療用鉗子に改良を加え,カテーテル型吻合装置を考案した.【対象と方法】食用ブタをもちいた.宿主血管とグラフトとステプラーで吻合することが可能なカテーテルを作成した.改良した血管視鏡の観察下に吻合を行った.【結果】80mmHg程の血圧ではずれたももあったが,改良した.3.カテーテル型圧着装置の開発【対象と方法】食用ブタをもちいた.血管内腔とステントグラフトを圧着固定するカテーテルを作成した.ステントを留置した後に,本装置で拡張した.【結果】拡張力は十分であったが,過剰な加圧により大動脈損傷を来した.比較的軽微な内膜損傷であった.2.心腔内手術【対象と方法】ブタ心臓を用いた。心房に切開を加え、超音波CCDカメラ下に鏡視下手術用鉗子および剪刀を用い心房中隔に5mm程度の穴を開け心房中隔欠損モデルを作製した。欠損部にカテーテル型縫合装置を用い、フェルト片を縫合した。【結果】モニター上では距離感の把握が困難であったが、全例予定部位に欠損モデルを作製でき、またフェルト片を縫合し得えた。カテーテル型縫合装置は把持力も十分であり、リークも認めなかった。2.大血管手術【対象と方法】ブタを用い全身麻酔下に開胸開腹した.ステントグラフトを末梢側の大動脈から挿入した.以下の各群を作成した.A群:X線透視下に左鎖骨下動脈直下にステントグラフトを留置.B群:バルーン付血管内視鏡補助下に左鎖骨下動脈直下にステントグラフトを留置.さらにB1群:ステントグラフト留置のみを施行.B2群:ステントグラフトを留置後、血管吻合用カテーテルを用い中枢側のみ内膜からグラフトと宿主血管を吻合.B3群:ステントグラフトを留置後、圧着を施行.を作成した.【結果】術直後に,大動脈に切開を加えA,B群間でステントグラフト留置の正確さについて検討した.左鎖骨下動脈から留置されたステントグラフトまでの距離(の誤差)は両群間で有意差はなかった.従来のX線透視使用の留置も正確ではあるが,内視鏡使用でも正確に留置しえ今後の応用が期待された.B2,3群の血管吻合用カテーテルを用いた郡では,ステープルをかけた部分に問題となるような内膜の損傷は認められなかった.また,遠隔期も問題はなかった.[Introduction]Off-pump CABG became standard for ischemic heart diseases, and the endovascular therapy came to be an important treatment strategy for the peripheral arterial diseases today. However, the intracardic operations or the aortic operations have not been established like this less invasive procedures, because the enough view is not gotten with the filled blood. Usage of the heart-lung machine is still indispensable for these operations now, and the incidence of postoperative complications is also high. An epoch-making treatment like as stentgrafting custody is developed, and there are several problems to be.solved. In this report, we developed the devices for less-invasive intracardiac and aortic surgeries. These basic experiments were performed by pigs.1.Development of the angioscopeThe improvement was added to the angioscope as follows; The balloon made of the urethane was inflated by CO_2. The satisfied view was obtained.. No damage in the aorta was caused because of the balloon expansion. The thrombosis was not detected by this procedure.2.Development of the catheter with staplerThe catheter type stapler was designed. The anastmosis between the artificial graft and the aorta was performed easily and safely.3.Development of catheter type post-dolatation deviceThe dilatation devise was made of metallic wire instead of the balloon. There was no significant aortic damage by the post-dilatation. The fixation between the artificial graft and the aorta was increased.4.Intracardic operationBy ultrasonic CCD camera, the intracardiac structures were observed. Experimental ASD closure was tried. The observation by the ultrasonic CCD camera was easil and clearly. However, the device size is too large, and it is difficult to use this device clinically now.5.Aortic surgery using new devicesThe devices developed by this experiment 1, 2, and 2 was totally examined. Under angioscopic observation, the stentgraft deployment was smoothly. Furthermore, the staplers were effective.[Conclusion]In this series, The attractive devices for cardiovascular surgery were developed. Though there are several problems for clinical trial, the technical innovation will solve in future.研究課題/領域番号:14370406, 研究期間(年度):2002 – 2003出典:「超音波CCDカメラを用いた完全鏡視下心腔内・大血管内手術systemの開発」研究成果報告書 課題番号14370406(KAKEN:科学研究費助成事業データベース(国立情報学研究所))(https://kaken.nii.ac.jp/ja/report/KAKENHI-PROJECT-14370406/143704062003kenkyu_seika_hokoku_gaiyo/)を加工して作
超音波CCDカメラを応用した心臓・血管内可視化の基礎的研究
金沢大学医薬保健研究域医学系1)超音波CCDカメラによる心臓弁(大動脈弁)の観察【方法】ブタの心臓から大動脈弁を取り出す。ブタ血液で満たしたシャーレに正常大動脈弁および(弁の一部に切開を加えた)閉鎖不全大動脈弁をそれぞれ入れ、超音波CCDカメラにて観察した。【結果】血液で充満されているため肉眼的(光学的)には可視不能であった弁構造であるが、弁の開放、閉鎖および閉鎖不全状態が、超音波CCDカメラでは鮮明なリアルタイム動画として観察可能であった。2)超音波CCDカメラによる血管内の観察【方法】ブタの上行大動脈を取り出し、大動脈内膜に切開を加え大動脈解離モデルを作製した。ブタ血液で満たしたシャーレに縦切開を加え広げた大動脈を入れ、内腔面を超音波CCDカメラにて観察した。次に血管内腔面に固定した人工血管を同様に観察した。【結果】血液によって肉眼的(光学的)には可視不能であった血管内腔面であるが、超音波CCDカメラでは正常部位および解離部位(いわゆるエントリー部性状)の把握は充分可能であった。人工血管付着部の境界も十分に観察可能であった。3)超音波CCDカメラを応用した心臓内手術手技の確立【方法】ブタの心房中隔を取り出し、5mm程度の穴を開け心房中隔欠損モデルを作製した。超音波CCDカメラ使用下に内視鏡用手術鉗子および外科用クリップにて心房中隔欠損の閉鎖を行った。【結果】閉鎖には外科用フェルトを用いた。欠損部位の観察、および鉗子等の動きはリアルタイム動画で観察可能であり、予定部位の閉鎖が行えた。今後はクリップの改良(細小化)が必要であると考えた。研究課題/領域番号:14657318, 研究期間(年度):2002 – 2003出典:「超音波CCDカメラを応用した心臓・血管内可視化の基礎的研究」研究成果報告書 課題番号14657318(KAKEN:科学研究費助成事業データベース(国立情報学研究所))(https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-14657318/)を加工して作
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