174 research outputs found
Drum Beating and a Martial Art Bojutsu Performed by a Humanoid Robot
Over the past few decades a considerable number of studies have been made on impact dynamics. Zheng and Hemami discussed a mathematical model of a robot that collides with an environment (Zheng & Hemami, 1985). When a robot arm fixed on the ground collides with a hard environment, the transition from the free space to constrained space may bring instabilit
断片的な観測データから慢性疾患の長期的な病態進行を推定する新規統計手法の構築
学位の種別: 課程博士審査委員会委員 : (主査)東京大学教授 鈴木 洋史, 東京大学教授 堀 昌平, 東京大学教授 楠原 洋之, 東京大学教授 池谷 裕二, 東京大学教授 富田 泰輔University of Tokyo(東京大学
Cognitive function during exercise under severe hypoxia
Acute exercise has been demonstrated to improve cognitive function. In contrast, severe hypoxia can impair cognitive function. Hence, cognitive function during exercise under severe hypoxia may be determined by the balance between the beneficial effects of exercise and the detrimental effects of severe hypoxia. However, the physiological factors that determine cognitive function during exercise under hypoxia remain unclear. Here, we examined the combined effects of acute exercise and severe hypoxia on cognitive function and identified physiological factors that determine cognitive function during exercise under severe hypoxia. The participants completed cognitive tasks at rest and during moderate exercise under either normoxic or severe hypoxic conditions. Peripheral oxygen saturation, cerebral oxygenation, and middle cerebral artery velocity were continuously monitored. Cerebral oxygen delivery was calculated as the product of estimated arterial oxygen content and cerebral blood flow. On average, cognitive performance improved during exercise under both normoxia and hypoxia, without sacrificing accuracy. However, under hypoxia, cognitive improvements were attenuated for individuals exhibiting a greater decrease in peripheral oxygen saturation. Cognitive performance was not associated with other physiological parameters. Taken together, the present results suggest that arterial desaturation attenuates cognitive improvements during exercise under hypoxia
Effectiveness of Photodynamic Therapy and Nd-YAG Laser Treatment for Obstructed Tracheobronchial Malignancies
Since 1980, advanced lung carcinomas were treated with palliative laser therapy for the
purpose of opening the endobronchial stenosis and obstruction by either photodynamic
therapy (PDT) or Nd-YAG laser treatment at Tokyo Medical University. A total of 258
lesions were treated, 81 by PDT and 177 by Nd-YAG laser treatment. PDT achieved effective
results in 61 (75%) of 81 lesions. In the Nd-YAG laser group, 143 (81%) of 177 lesions showed
effective results. When the tumor was located in the trachea or main bronchi, effective results
were obtained in 73% (19 of 26) of cases treated by PDT and in 93% of cases (64 of 69) treated
by Nd-YAG laser. However, in cases in which the tumor was located in lobar or segmental
bronchi, the tumor response was effective in 76% (42 of 55) of PDT-treated patients and 73%
(79 of 108) of Nd-YAG laser-treated patients. With a mortality rate of 0%, the greatest
advantage of PDT over Nd-YAG treatment was safety. Considering complications, PDT
seems to be useful for obstruction of lobar and segmental bronchus. Nevertheless, when
deciding among alternative therapies, physicians treating patients with advanced lung
carcinoma should give careful consideration to the benefit and complications of both laser
therapies and decide the most suitable modality
Lung Cancers Treated With Photodynamic Therapy and Surgery
Laser endoscopic surgery, especially the effectiveness of photodynamic therapy (PDT) using
Photofrin as a photosensitizer, has now achieved a status as effective treatment modality for
lung cancer. Twenty-six lung cancer patients received the preoperative PDT for the purpose of
either reducing the extent of resection or increasing operability. Bronchoscopical PDT is
performed with topical anesthesia approximately 48 h after the intravenous injection of
2.0 mg/kg body weight of Photofrin. Operation was performed 2–9 weeks after initial PDT. The initial purpose of PDT, i.e. either to reduce the extent of resection or convert inoperable
disease to operable status, was achieved in 22 out of 26 patients treated. The survival rate of T3
(main bronchus invasion) cases treated by surgery alone increased significantly from 50.9% to
60.0% with the application of preoperative PDT. This remarkable result may imply that this
new option of PDT as preoperative laser irradiation may contribute to the management of
advanced lung malignancy
Smart Integrated Sensor for Multiple Detections of Glucose and L-Lactate Using On-Chip Electrochemical System
Multiple sensor electrodes, a supplementary electrode, a reference electrode, and signal-processing circuits were integrated on a single chip to develop a chip-shaped electrochemical sensing system. L-lactate and glucose were measured using on-chip working electrodes modified by polyion complex to immobilize lactate oxidase and glucose oxidase, respectively. Cyclic voltammetry measurements were conducted using an on-chip potentiostat. Selective and quantitative detection of glucose and L-lactate and the interference behavior were studied. Hydrogen peroxide generated by enzymatic reactions was detected by an increase in anodic oxidation current. Reaction currents at +0.7 V versus Ag/AgCl were used to obtain calibration plots. The measured dynamic ranges for L-lactate and glucose were 0.2–1.0 mM and 2.0–8.0 mM, respectively. The sensitivities were 65 nA/mM and 15 nA/mM, respectively, using a working electrode of 0.5 mm2. The 3σ detection limit was 0.19 mM and 1.1 mM, respectively. We have achieved multiple biomaterial detections on a circuit-equipped single chip. This integrated electrochemical sensor chip could be the best candidate for realizing point-of-care testing due to its portability and potential for mass production
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