Closed-loop

闭环
  • 文章类型: Journal Article
    经皮耳迷走神经刺激(taVNS)引起了中风康复的关注,研究表明,当与运动康复训练结合或在运动训练前交付时,它的好处。尚不清楚将taVNS与运动训练同时应用于中风后运动康复的必要性。我们旨在研究通过肌电图(EMG)触发的闭环系统与运动训练同时应用taVNS进行中风后康复的必要性和优势。
    我们提出了一种双盲,随机临床试验涉及150名中风患者,分为三组:并发taVNS,顺序taVNS,或假控制条件。在并发组中,在康复训练期间,taVNS爆发将通过EMG触发的闭环系统与上肢运动同步,而在顺序组中,运动康复训练之前将进行taVNS课程。TaVNS强度将被设定为低于同时和顺序条件的疼痛阈值,并且对于对照条件为零。主要结果测量是上肢的Fugl-Meyer评估(FMA-UE)。次要措施包括标准的上肢功能评估,以及EMG和心电图(ECG)特征。
    已获得医学伦理委员会的伦理批准,附属南方医科大学珠江医院临床研究(2023-QX-012-01)。本研究已在临床试验(NCT05943431)上注册。签署的知情同意书将从所有参与者获得。研究结果将发表在同行评审的期刊上,并在相关的利益相关者会议上发表。
    这项研究代表了一项开创性的工作,直接比较了并发taVNS与运动训练与顺序taVNS与运动训练对中风康复的影响。其次,EMG触发的闭环taVNS系统的整合使taVNS和多种运动训练任务的自动化和个性化成为可能-这是先前研究中未探索的新颖方法。这项技术进步有望为中风患者提供更精确和量身定制的培训干预措施。然而,必须承认这项研究的局限性,因为它没有深入研究卒中后康复背景下taVNS的神经机制。
    UNASSIGNED: Transcutaneous auricular vagus nerve stimulation (taVNS) has garnered attention for stroke rehabilitation, with studies demonstrating its benefits when combined with motor rehabilitative training or delivered before motor training. The necessity of concurrently applying taVNS with motor training for post-stroke motor rehabilitation remains unclear. We aimed to investigate the necessity and advantages of applying the taVNS concurrently with motor training by an electromyography (EMG)-triggered closed-loop system for post-stroke rehabilitation.
    UNASSIGNED: We propose a double-blinded, randomized clinical trial involving 150 stroke patients assigned to one of three groups: concurrent taVNS, sequential taVNS, or sham control condition. In the concurrent group, taVNS bursts will synchronize with upper extremity motor movements with EMG-triggered closed-loop system during the rehabilitative training, while in the sequential group, a taVNS session will precede the motor rehabilitative training. TaVNS intensity will be set below the pain threshold for both concurrent and sequential conditions and at zero for the control condition. The primary outcome measure is the Fugl-Meyer Assessment of Upper Extremity (FMA-UE). Secondary measures include standard upper limb function assessments, as well as EMG and electrocardiogram (ECG) features.
    UNASSIGNED: Ethical approval has been granted by the Medical Ethics Committee, affiliated with Zhujiang Hospital of Southern Medical University for Clinical Studies (2023-QX-012-01). This study has been registered on ClinicalTrials (NCT05943431). Signed informed consent will be obtained from all included participants. The findings will be published in peer-reviewed journals and presented at relevant stakeholder conferences and meetings.
    UNASSIGNED: This study represents a pioneering effort in directly comparing the impact of concurrent taVNS with motor training to that of sequential taVNS with motor training on stroke rehabilitation. Secondly, the incorporation of an EMG-triggered closed-loop taVNS system has enabled the automation and individualization of both taVNS and diverse motor training tasks-a novel approach not explored in previous research. This technological advancement holds promise for delivering more precise and tailored training interventions for stroke patients. However, it is essential to acknowledge a limitation of this study, as it does not delve into examining the neural mechanisms underlying taVNS in the context of post-stroke rehabilitation.
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  • 文章类型: Journal Article
    植入式神经调节装置具有显著先进的治疗神经系统疾病,如帕金森病,癫痫,和抑郁症。传统的开环设备,如深部脑刺激(DBS)和脊髓刺激器(SCS)通常会导致过度刺激,缺乏自适应精度,提高安全性和副作用的担忧。下一代闭环系统提供实时监测和设备上诊断,以响应刺激,在治疗一系列脑部疾病方面取得了重大进展。然而,当前闭环技术的高误报率限制了其功效,并由于不必要的刺激而增加了能耗。在这项研究中,我们介绍了一种针对这些问题的人工智能-集成电路协同设计,并使用在线演示系统进行闭环癫痫发作预测,以展示其有效性。首先,通过神经网络搜索和量化策略获得了两个神经网络模型。优化了二进制神经网络,以实现高灵敏度的最小计算,并优化了卷积神经网络,其误报率低至0.1/h,以拒绝误报。然后,一个专用的低功耗处理器采用55纳米技术制造,以实现这两个模型。通过可重新配置的设计和事件驱动的处理功能,最终的专用集成电路(ASIC)仅占用5mm2的硅面积,平均功耗为142μW。所提出的解决方案在针对现有技术的对应物进行基准测试时实现了错误警报率和功耗的显著降低。
    Implantable neuromodulation devices have significantly advanced treatments for neurological disorders such as Parkinson\'s disease, epilepsy, and depression. Traditional open-loop devices like deep brain stimulation (DBS) and spinal cord stimulators (SCS) often lead to overstimulation and lack adaptive precision, raising safety and side-effect concerns. Next-generation closed-loop systems offer real-time monitoring and on-device diagnostics for responsive stimulation, presenting a significant advancement for treating a range of brain diseases. However, the high false alarm rates of current closed-loop technologies limit their efficacy and increase energy consumption due to unnecessary stimulations. In this study, we introduce an artificial intelligence-integrated circuit co-design that targets these issues and using an online demonstration system for closed-loop seizure prediction to showcase its effectiveness. Firstly, two neural network models are obtained with neural-network search and quantization strategies. A binary neural network is optimized for minimal computation with high sensitivity and a convolutional neural network with a false alarm rate as low as 0.1/h for false alarm rejection. Then, a dedicated low-power processor is fabricated in 55 nm technology to implement the two models. With reconfigurable design and event-driven processing feature the resulting application-specific integrated circuit (ASIC) occupies only 5mm2 silicon area and the average power consumption is 142 μW. The proposed solution achieves a significant reduction in both false alarm rates and power consumption when benchmarked against state-of-the-art counterparts.
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  • 文章类型: Journal Article
    为了提高糖尿病患者的生活水平,减少这种疾病对健康的负面影响,医学界一直在积极寻找更有效的治疗方法。近年来,人工胰腺已成为治疗糖尿病的重要方法。尽管最近取得了这些进展,满足小型化尺寸的要求,准确的传感和大容量抽水能力仍然是一个巨大的挑战。这里,我们提出了一种新颖的小型化人工胰腺,其基础是与超声波泵集成的长微管传感器。我们的设备满足实现精确传感和高泵送能力的要求。人造胰腺是基于低成本的长微管构建的,无痛且操作简单,其中微管的外部被制造为用于检测糖尿病的葡萄糖传感器,并且微管的内部被用作用于通过超声泵递送胰岛素的通道。这项工作成功地实现了对大鼠血糖的闭环控制和糖尿病的治疗。预计这项工作可以为微系统的开发开辟新的方法,并提出糖尿病患者的管理方法。
    In order to improve the living standards of diabetes patients and reduce the negative health effects of this disease, the medical community has been actively searching for more effective treatments. In recent years, an artificial pancreas has emerged as an important approach to managing diabetes. Despite these recent advances, meeting the requirements for miniaturized size, accurate sensing and large-volume pumping capability remains a great challenge. Here, we present a novel miniaturized artificial pancreas based on a long microtube sensor integrated with an ultrasonic pump. Our device meets the requirements of achieving both accurate sensing and high pumping capacity. The artificial pancreas is constructed based on a long microtube that is low cost, painless and simple to operate, where the exterior of the microtube is fabricated as a glucose sensor for detecting diabetes and the interior of the microtube is used as a channel for delivering insulin through an ultrasonic pump. This work successfully achieved closed-loop control of blood glucose and treatment of diabetes in rats. It is expected that this work can open up new methodologies for the development of microsystems, and advance the management approach for diabetes patients.
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  • 文章类型: Journal Article
    事故引起的慢性伤口,手术,或疾病造成重大的临床和经济负担,强调需要有效的解决方案来预防严重的并发症。材料科学和电化学技术的最新进展促进了用于检测和管理的一致电化学平台的发展,纳入监测,诊断,和治疗。然而,当前的伤口检测和治疗系统面临与传感器监测的稳定性和特异性相关的挑战,以及需要现场和全面的评估标准,以提供及时的治疗指导和后续护理。这篇综述全面概述了闭环管理系统,强调伤口生物标志物检测,伤口评估,和按需治疗,最终通过一致的电化学装置形成综合的伤口管理方法。此外,我们探索挑战,机遇,以及柔性和可拉伸电化学生物传感器的未来前景,目的是提高伤口管理的效率和及时性。
    Chronic wounds arising from accidents, surgeries, or diseases impose a significant clinical and economic burden, underscoring the need for effective solutions to prevent severe complications. Recent advancements in materials science and electrochemical technology have facilitated the development of conformable electrochemical platforms for detection and management, incorporating monitoring, diagnosis, and treatment. Nevertheless, current wound detection and therapy systems face challenges related to the stability and specificity of sensor monitoring, as well as the need for on-site and comprehensive evaluation criteria to offer timely treatment guidance and follow-up care. This review provides a comprehensive overview of the closed-loop management system, emphasizing wound biomarker detection, wound assessment, and on-demand treatment, ultimately culminating in an integrated wound management approach by conformable electrochemical devices. Additionally, we explore the challenges, opportunities, and future prospects of soft and stretchable electrochemical biosensors, with the aim of enhancing the efficiency and timeliness of wound management.
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  • 文章类型: Journal Article
    最近,软执行器引起了人们对下一代软机器人的极大兴趣。尽管取得了重大进展,当前的大多数软致动器都缺乏实时感觉反馈和自我控制功能,禁止其有效的传感和多任务处理功能。因此,在这项工作中,近红外驱动的双压电晶片膜,具有自感知和反馈回路控制功能,通过逐层(LBL)将MXene/PDDA(PM)组装到液晶弹性体(LCE)膜上而产生。多功能集成策略成功地防止了由于传感层和致动层之间的模量不匹配而产生的分离问题,最终导致稳定和紧密结合的界面粘合。因此,所得膜表现出优异的机械韧性(拉伸强度等于16.3MPa(||)),强致动特性(致动应力等于1.56MPa),和稳定的自感(gaugefactor等于4.72)能力。当应用近红外(NIR)激光控制时,系统可以进行抓取,牵引力,和爬行动作。此外,结合昆虫微控制器单元(MCU)模型演示了机翼致动和闭环控制运动。软执行器的远程精确控制和自感知能力为将来复杂而精确的任务调制铺平了道路。
    More recently, soft actuators have evoked great interest in the next generation of soft robots. Despite significant progress, the majority of current soft actuators suffer from the lack of real-time sensory feedback and self-control functions, prohibiting their effective sensing and multitasking functions. Therefore, in this work, a near-infrared-driven bimorph membrane, with self-sensing and feedback loop control functions, is produced by layer by layer (LBL) assembling MXene/PDDA (PM) onto liquid crystal elastomer (LCE) film. The versatile integration strategy successfully prevents the separation issues that arise from moduli mismatch between the sensing and the actuating layers, ultimately resulting in a stable and tightly bonded interface adhesion. As a result, the resultant membrane exhibited excellent mechanical toughness (tensile strengths equal to 16.3 MPa (||)), strong actuation properties (actuation stress equal to 1.56 MPa), and stable self-sensing (gauge factor equal to 4.72) capabilities. When applying the near-infrared (NIR) laser control, the system can perform grasping, traction, and crawling movements. Furthermore, the wing actuation and the closed-loop controlled motion are demonstrated in combination with the insect microcontroller unit (MCU) models. The remote precision control and the self-sensing capabilities of the soft actuator pave a way for complex and precise task modulation in the future.
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  • 文章类型: Journal Article
    本研究旨在探讨闭环经颅超声刺激(闭环TUS)作为一种非侵入性,高时空分辨率的方法,用于调节大脑功能以增强记忆。为此,我们在theta周期的不同阶段连续7天对大鼠海马CA1区应用闭环TUS.干预之后,我们通过行为测试评估记忆表现,并记录神经活动.我们的结果表明,在θ周期的峰值阶段应用闭环TUS显着改善了大鼠的记忆性能,行为测试证明了这一点。此外,我们观察到闭环TUS在记忆任务期间改变了局部场电位(LFP)的功率和交叉频率耦合强度,以及调节神经元活动模式和突触传递,取决于刺激相对于θ节律的相位。我们证明了闭环TUS可以以相位依赖性方式调节神经活动和记忆性能。具体来说,我们观察到闭环TUS在调节神经活动和记忆方面的有效性取决于不同θ相的刺激时间.研究结果表明,闭环TUS可能具有以相位敏感方式改变神经活动和记忆表现的能力,并表明闭环TUS在改变神经活动和记忆方面的功效取决于刺激对theta节律的时间。此外,发现闭环TUS后内存性能的改善是持久的。
    The present study aimed to investigate the effectiveness of closed-loop transcranial ultrasound stimulation (closed-loop TUS) as a non-invasive, high temporal-spatial resolution method for modulating brain function to enhance memory. For this purpose, we applied closed-loop TUS to the CA1 region of the rat hippocampus for 7 consecutive days at different phases of theta cycles. Following the intervention, we evaluated memory performance through behavioral testing and recorded the neural activity. Our results indicated that closed-loop TUS applied at the peak phase of theta cycles significantly improves the memory performance in rats, as evidenced by behavioral testing. Furthermore, we observed that closed-loop TUS modifies the power and cross-frequency coupling strength of local field potentials (LFPs) during memory task, as well as modulates neuronal activity patterns and synaptic transmission, depending on phase of stimulation relative to theta rhythm. We demonstrated that closed-loop TUS can modulate neural activity and memory performance in a phase-dependent manner. Specifically, we observed that effectiveness of closed-loop TUS in regulating neural activity and memory is dependent on the timing of stimulation in relation to different theta phase. The findings implied that closed-loop TUS may have the capability to alter neural activity and memory performance in a phase-sensitive manner, and suggested that the efficacy of closed-loop TUS in modifying neural activity and memory was contingent on timing of stimulation with respect to the theta rhythm. Moreover, the improvement in memory performance after closed-loop TUS was found to be persistent.
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  • 文章类型: Randomized Controlled Trial
    背景:这项随机和对照的前瞻性研究验证了以下假设:与开环控制的丙泊酚相比,丙泊酚的闭环靶控输注(TCI)与更好的系统性能相关。
    方法:将择期乳房手术的患者随机分为两组:闭环组,通过闭环TCI系统进行丙泊酚输注,该系统使用双频指数(BIS)作为反馈参数来滴定丙泊酚输注速率,和一个开环组,其中丙泊酚输注是手动进行的,并由双频指数指导。
    结果:本研究共招募了156名患者(闭环组n=79;开环组n=77)。闭环组的全局评分(GS)低于开环组(34.3和42.2)(p=0.044)。BIS值在40和60之间的时间比例在闭环组和开环组中几乎相同(68.7±10.6%和66.7±13.3%)(p=0.318)。与开环组相比,闭环组的个体消耗更多的异丙酚(7.20±1.65mg。kg-1.h-1vs.6.03±1.31mg。kg-1.h-1,p<0.001)。没有术中召回,躯体事件或不良事件发生。两组之间的心率没有显着差异(p=0.169)。
    结论:闭环方案与较低的BIS变异性和较低的超出范围BIS值相关,与开环组相比,丙泊酚的消耗量更大。
    ChiCTR-INR-17010399。
    BACKGROUND: This randomized and controlled prospective study tested the hypothesis that closed-loop Target-Controlled Infusion (TCI) of propofol would be associated with better system performance when compared with open-loop controlled delivery of propofol.
    METHODS: Patients scheduled for elective breast surgery were randomly assigned to two groups: a closed-loop group, in which propofol infusion was performed by a closed-loop TCI system that used the Bispectral Index (BIS) as a feedback parameter to titrate the rate of propofol infusion, and an open-loop group, in which propofol infusion was performed manually and guided by the bispectral index.
    RESULTS: A total of 156 patients were recruited for this study (closed-loop group n = 79; open-loop group n = 77). The Global Score (GS) of the closed-loop group was lower than that of the open-loop group (34.3 and 42.2) (p = 0.044). The proportions of time with a BIS value between 40 and 60 were almost identical in the closed-loop group and the open-loop group (68.7 ± 10.6% and 66.7 ± 13.3%) (p = 0.318). The individuals in the closed-loop group consumed more propofol compared with those in the open-loop group (7.20 ± 1.65 mg.kg-1.h-1 vs. 6.03 ± 1.31 mg.kg-1.h-1, p < 0.001). No intraoperative recall, somatic events or adverse events occurred. No significant difference in heart rate was observed between the two groups (p = 0.169).
    CONCLUSIONS: The closed-loop protocol was associated with lower BIS variability and lower out-of-range BIS values, at the cost of a greater consumption of propofol when compared to the open loop group.
    UNASSIGNED: ChiCTR-INR-17010399.
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  • 文章类型: Journal Article
    帕金森病(Parkinson’sdisease,PD)是一种神经退行性疾病,给患者带来了沉重的负担,家庭,和社会。深部脑刺激(DBS)可以改善药物不足的PD患者的症状。然而,当前开环不间断常规DBS(cDBS)具有固有的局限性,如不良影响,快速的电池消耗,并且需要频繁的参数调整。为了克服这些缺点,提出了自适应DBS(aDBS)来为PD提供响应性优化刺激。这个话题引起了科学的兴趣,越来越多的临床前和临床证据表明了它的好处。然而,在这个新颖的领域中,既有成就,也有挑战。迄今为止,只有有限的审查全面分析了aDBS实施的完整框架和程序。在这里,我们回顾了目前用于PD的aDBS的临床前和临床数据,以讨论其实现的全部程序,并提供关于该治疗的未来观点.
    Parkinson\'s disease (PD) is a neurodegenerative disease with a heavy burden on patients, families, and society. Deep brain stimulation (DBS) can improve the symptoms of PD patients for whom medication is insufficient. However, current open-loop uninterrupted conventional DBS (cDBS) has inherent limitations, such as adverse effects, rapid battery consumption, and a need for frequent parameter adjustment. To overcome these shortcomings, adaptive DBS (aDBS) was proposed to provide responsive optimized stimulation for PD. This topic has attracted scientific interest, and a growing body of preclinical and clinical evidence has shown its benefits. However, both achievements and challenges have emerged in this novel field. To date, only limited reviews comprehensively analyzed the full framework and procedures for aDBS implementation. Herein, we review current preclinical and clinical data on aDBS for PD to discuss the full procedures for its achievement and to provide future perspectives on this treatment.
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  • 文章类型: Journal Article
    本文提出了一种基于环形二极管电容检测的高线性闭环电容加速度计的实现方案和实验评估。通过推导考虑二极管影响的环形二极管电容检测模型,校正了现有的环形二极管的理论模型误差,并设计了重用MEMS芯片的检测电极和控制电极的闭环方案,将该检测方案应用于平行板加速度计,只有三个独立的电极。在分析了现有闭环控制方案中存在的非线性问题后,提出了一种理论上绝对的线性闭环控制方案,结合闭环二极管检测实现了集成的闭环加速度计。环形二极管检测模型的实验结果与理论公式一致。闭环后±1g内加速度计的非线性度为130ppm,与使用开环时的1500ppm相比。
    This paper presents an implementation scheme and experimental evaluation of a high-linearity closed-loop capacitive accelerometer based on ring-diode capacitance detection. By deducing the capacitance detection model of the ring-diode considering the influence of the diode, the existing theoretical model error of the ring-diode is corrected and a closed-loop scheme of reusing the detection electrode and the control electrode of the MEMS die is designed to apply this detection scheme to the parallel-plate accelerometer, which only has three independent electrodes. After analyzing the non-linear problems in the existing closed-loop control schemes, a theoretically absolute linear closed-loop control scheme is proposed, and an integrated closed-loop accelerometer is realized by combining the closed-loop diode detection. The experimental results of the ring-diode detection model are in agreement with the theoretical formula. The non-linearity of the accelerometer within ±1 g after the closed-loop is 130 ppm, compared with 1500 ppm when the open-loop is used.
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  • 文章类型: Journal Article
    Objective.闭环经颅超声刺激(TUS)可以根据神经活动的状态在特定时间施加,以实现及时,精确的神经调制,提高调制效果。在之前的研究中,我们发现,在小鼠海马theta节律的波峰和波谷处的闭环TUS能够增加局部场电位(LFP)的theta节律的绝对功率并降低其相对功率,而与刺激的波峰和波谷无关.然而,目前尚不清楚这种闭环TUS诱导的小鼠海马神经振荡的调节作用是否取决于theta节律的峰和谷。方法。在这项研究中,我们使用不同刺激模式和持续时间的超声来刺激海马theta节律的峰(峰刺激)和谷(谷刺激)。记录超声刺激区域的LFP,并分析超声刺激前后θ节律的幅度和功率谱。主要结果。结果表明:(a)θ节律振幅的相对变化随峰值刺激试验次数的增加而减小;(b)θ节律绝对功率的相对变化随峰值刺激试验次数的增加而减小;(c)θ节律振幅的相对变化随峰值刺激持续时间(SD)呈非线性增加,(d)在峰值刺激下,绝对功率的相对变化随SD呈非线性增加。意义。这些结果表明,闭环TUS对theta节律的调节作用取决于峰值刺激下的刺激模式和持续时间。TUS具有精确调节theta节律相关神经活动的潜力。
    Objective. Closed-loop transcranial ultrasound stimulation (TUS) can be applied at a specific time according to the state of neural activity to achieve timely and precise neuromodulation and improve the modulation effect. In a previous study, we found that closed-loop TUS at the peaks and troughs of the theta rhythm in the mouse hippocampus was able to increase the absolute power and decrease the relative power of the theta rhythm of local field potentials (LFPs) independent of the peaks and troughs of the stimulus. However, it remained unclear whether the modulation effect of this closed-loop TUS-induced mouse hippocampal neural oscillation depended on the peaks and troughs of the theta rhythm.Approach. In this study, we used ultrasound with different stimulation modes and durations to stimulate the peaks (peak stimulation) and troughs (trough stimulation) of the hippocampal theta rhythm. The LFPs in the area of ultrasound stimulation were recorded and the amplitudes and power spectra of the theta rhythm before and after ultrasound stimulation were analyzed.Main results. The results showed that (a) the relative change in amplitude of theta rhythm decreases as the number of stimulation trials under peak stimulation increases; (b) the relative change in the absolute power of the theta rhythm decreases as the number of stimulation trials under peak stimulation increases; (c) the relative change in amplitude of the theta rhythm increases nonlinearly with the stimulation duration (SD) under peak stimulation, and; (d) the relative change in absolute power exhibits a nonlinear increase with SD under peak stimulation.Significance. These results suggest that the modulation effect of closed-loop TUS on theta rhythm is dependent on the stimulation mode and duration under peak stimulation. TUS has the potential to precisely modulate theta rhythm-related neural activity.
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