142 research outputs found

    Trajectory Tracking Control of Dual-PAM Soft Actuator with Hysteresis Compensator

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    Soft robotics is a swiftly evolving field. Pneumatic actuators are suitable for driving soft robots because of their superior performance. However, their control is challenging due to the hysteresis characteristics. In response to this challenge, we propose an adaptive control method to compensate for the hysteresis of soft actuators. Employing a novel dual pneumatic artificial muscle (PAM) bending actuator, the innovative control approach abates hysteresis effects by dynamically modulating gains within a traditional PID controller corresponding to the predicted variation of the reference trajectory. Through experimental evaluation, we found that the proposed control method outperforms its conventional counterparts regarding tracking accuracy and response speed. Our work reveals a new direction for advancing model-free control in soft actuators.Comment: This paper has been published in the IEEE Robotics and Automation Letters ,DOI 10.1109/LRA.2023.3334098, copyright has been transfferd to the IEEE. Final version is available at IEEE Xplor

    Two Degree of Freedom Adaptive Control for Hysteresis Compensation of Pneumatic Continuum Bending Actuator

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    Soft robotics, with their inherent flexibility and infinite degrees of freedom (DoF), offer promising advancements in human-machine interfaces. Particularly, pneumatic artificial muscles (PAMs) and pneumatic bending actuators have been fundamental in driving this evolution, capitalizing on their mimetic nature to natural muscle movements. However, with the versatility of these actuators comes the intricate challenge of hysteresis - a nonlinear phenomenon that hampers precise positioning, especially pronounced in pneumatic actuators due to gas compressibility. In this study, we introduce a novel 2-DoF adaptive control for precise bending tracking using a pneumatic continuum actuator. Notably, our control method integrates adaptability into both the feedback and the feedforward element, enhancing trajectory tracking in the presence of profound nonlinear effects. Comparative analysis with existing approaches underscores the superior tracking accuracy of our proposed strategy. This work discusses a new way of simple yet effective control designs for soft actuators with hysteresis properties.Comment: Submitted to IEEE Conference on Robotics and Automation (ICRA 2024), Under Revie

    Psychological state in cancer patients

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    The psychological state and changes over time of cancer patients in the active treatment stage were classified into emotions by the speech and behavior of the patient described in the medical record article of the cancer psychological interview record, and the analysis of the ā€œemotional state mapā€ was attempted. In all cases, positive / negative emotions were mixed and appeared with variation, but a relatively large number of positive emotions, including , , and , were manifested, and the same was true in patients who experienced stressful treatment events. In the background, the existence of appropriate support from medical professionals and psychological characteristics peculiar to the stage of active treatment was inferred, such as the active treatment of the target patient, the hospitalization environment in which mental and physical pain promptly appealed to medical professionals, and the influence of psychological interviews. Cancer patients during active treatment perceived and expressed changes in the body and pain caused by the disease, and after responses from medical professionals and family members, they were conscious of their physical condition and emotions. It is suggested that this analysis method helps to objectively understand and explain the invisible and ever-changing psychological state of cancer patients in the active treatment stage

    Zolpidem therapy in dystonia

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    Although there are some newly developed options to treat dystonia, its medical treatment is not always satisfactory. Zolpidem, an imidazopyridine agonist with a high affinity on benzodiazepine subtype receptor BZ1 (Ļ‰1), was found to improve clinical symptoms of dystonia in a limited number of case reports. To investigate what subtype of dystonia is responsive to the therapy, we conducted an open label study to assess the efficacy of zolpidem (5ā€“20 mg) in 34 patients suffering from miscellaneous types of dystonia using the Burkeā€“Fahnā€“Marsden Dystonia Rating Scale (BFMDRS). Patients were entered into the study if they had been refractory to other medications as evaluated by BFMDRS (no change in the previous two successive visits). After zolpidem therapy, the scores in the patients as a whole were decreased from 7.2 Ā± 7.9 to 5.5 Ā± 5.0 (P = 0.042). Patients with generalized dystonia, Meige syndrome/blepharospasm, and hand dystonia improved in the scale by 27.8, 17.8, and 31.0%, respectively, whereas no improvement was found in cervical dystonia patients. Overall response rate among patients were comparable to that of trihexyphenidyl. Zolpidem may be a therapeutic option for generalized dystonia, Meige syndrome, and hand dystonia including musicianā€™s. Drowsiness was the dose-limiting factor

    Efficacy of Zolpidem for Dystonia: A Study Among Different Subtypes

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    Although there are some newly developed options to treat dystonia, its medical treatment is not always satisfactory. Zolpidem, an imidazopyridine agonist with a high affinity on benzodiazepine subtype receptor BZ1 (Ļ‰1), was found to improve clinical symptoms of dystonia in a limited number of case reports. To investigate what subtype of dystonia is responsive to the therapy, we conducted an open label study to assess the efficacy of zolpidem (5ā€“20ā€‰mg) in 34 patients suffering from miscellaneous types of dystonia using the Burkeā€“Fahnā€“Marsden Dystonia Rating Scale (BFMDRS). Patients were entered into the study if they had been refractory to other medications as evaluated by BFMDRS (no change in the previous two successive visits). After zolpidem therapy, the scores in the patients as a whole were decreased from 7.2ā€‰Ā±ā€‰7.9 to 5.5ā€‰Ā±ā€‰5.0 (Pā€‰=ā€‰0.042). Patients with generalized dystonia, Meige syndrome/blepharospasm, and hand dystonia improved in the scale by 27.8, 17.8, and 31.0%, respectively, whereas no improvement was found in cervical dystonia patients. Overall response rate among patients were comparable to that of trihexyphenidyl. Zolpidem may be a therapeutic option for generalized dystonia, Meige syndrome, and hand dystonia including musicianā€™s. Drowsiness was the dose-limiting factor

    Effects of calcium channel blockers on glucose tolerance, inflammatory state, and circulating progenitor cells in non-diabetic patients with essential hypertension: a comparative study between Azelnidipine and amlodipine on glucose tolerance and endothelial function - a crossover trial (AGENT)

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    <p>Abstract</p> <p>Background</p> <p>Hypertension is associated with impaired glucose tolerance and insulin resistance. Medical treatment that interferes with various steps in the renin-angiotensin system improves glucose tolerance and insulin resistance. However, it remains unclear if long-acting calcium channel blockers (CCBs) such as azelnidipine and amlodipine affect glucose tolerance and insulin resistance in clinical practice.</p> <p>Methods</p> <p>Seventeen non-diabetic patients with essential hypertension who had controlled blood pressure levels using amlodipine (5 mg/day) were enrolled in this study. After randomization, either azelnidipine (16 mg/day) or amlodipine (5 mg/day) was administered in a crossover design for 12-weeks. At baseline and the end of each CCB therapy, samples of blood and urine were collected and 75 g oral glucose tolerance test (OGTT) was performed. In addition, hematopoietic progenitor cells (HPCs) were measured at each point by flow cytometry and endothelial functions were measured by fingertip pulse amplitude tonometry using EndoPAT.</p> <p>Results</p> <p>Although blood pressure levels were identical after each CCB treatment, the heart rate significantly decreased after azelnidipine administration than that after amlodipine administration (<it>P </it>< 0.005). Compared with amlodipine administration, azelnidipine significantly decreased levels of glucose and insulin 120 min after the 75 g OGTT (both <it>P </it>< 0.05). Serum levels of high-sensitivity C-reactive protein (<it>P </it>= 0.067) and interleukin-6 (<it>P </it>= 0.035) were decreased. Although endothelial functions were not different between the two medication groups, the number of circulating HPCs was significantly increased after azelnidipine administration (<it>P </it>= 0.016).</p> <p>Conclusions</p> <p>These results suggest that azelnidipine treatment may have beneficial effects on glucose tolerance, insulin sensitivity, the inflammatory state, and number of circulating progenitor cells in non-diabetic patients with essential hypertension.</p

    Epidermal growth factor signals regulate dihydropyrimidine dehydrogenase expression in EGFR-mutated non-small-cell lung cancer

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    Schematic diagrams of the signal cascade of EGF-induced DPD expression of EGFR-mutated type cells. TF, transcription factor; Mit A, mithramycin A. (JPG 130 kb
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