Biocybernetics and Biomedical Engineering最新文献_第3页

A morphometric lung model for evaluating lung aeration at birth 一种用于评估出生时肺通气的肺形态计量学模型

IF 6.6 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-10-01 DOI: 10.1016/j.bbe.2025.11.004

Chiara Veneroni , Enrico Conca , Davide Bizzotto , Kenneth Lutchen , Alberto Tosi , Raffaele L. Dellacà

Background

Lung aeration must rapidly develop at birth, but how to promote it without injuring the fragile lung is still unknown. Mathematical models simulating lung mechanics during this transition may help understand the underlying physiological mechanisms and design protective ventilation strategies. This study develops a morphologically-coherent computational lung model incorporating changing physical conditions during the transition from liquid-filled to gas-filled lungs.

Methods

We adapted a 3-D morphological model of the adult airway tree adjusting airway dimensions, lung volume, and lung tissue mechanical properties. Changes in resistance, inertia, and compliance during aeration were modeled by considering the differing properties of fetal fluid versus air. The capillary pressure at the liquid–air interface was computed using Laplace equation. Terminal airway diameters increased with lung volume due to airway-parenchymal interdependence. An integrated circuit simulator solved the entire network in the time domain.

Results

The air volume entering the model at different applied pressures increased exponentially with time. With 30 cmH₂O applied, lung volume reached total capacity after 15 s, matching lung aeration dynamics observed in animal models and human infants. In contrast, after the same time, at 15 cmH₂O, lung volume was slightly above functional residual capacity, and at 10 cmH₂O, it remained below.

Conclusions

The proposed in-silico newborn lung model simulates lung aeration at birth, allowing observation of the airway emptying sequence and the heterogeneity of aeration at each time point. Integrating this model with comprehensive acinar models may aid in defining protective resuscitation ventilation strategies for recruiting the lung minimizing risk of injuries.

出生时肺通气必须迅速发展，但如何在不伤害脆弱的肺的情况下促进肺通气仍是未知的。在这一转变过程中模拟肺力学的数学模型可能有助于理解潜在的生理机制和设计保护性通气策略。本研究开发了一个形态学一致的计算肺模型，该模型包含了从充液肺到充气肺过渡过程中不断变化的物理条件。方法采用成人气道树三维形态模型，调整气道尺寸、肺体积和肺组织力学特性。通过考虑胎液与空气的不同特性，模拟了通气过程中阻力、惯性和顺应性的变化。利用拉普拉斯方程计算了气液界面处的毛细压力。末端气道直径随着肺容量的增加而增加，这是由于气道与肺实质的相互依赖关系。一个集成电路模拟器在时域内求解了整个网络。结果在不同施加压力下进入模型的风量随时间呈指数增长。应用30 cmH2O时，肺容量在15 s后达到总容量，与动物模型和人类婴儿观察到的肺通气动态相匹配。相比之下，相同时间后，在15 cmH2O时，肺容量略高于功能剩余容量，而在10 cmH2O时，肺容量仍低于功能剩余容量。结论所建立的计算机新生儿肺模型模拟了新生儿出生时的肺通气，可以观察气道排空顺序和各时间点通气的异质性。将该模型与全面的腺泡模型相结合，可能有助于确定保护性复苏通气策略，以最大限度地降低肺损伤风险。

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引用次数: 0

Dual-peak cyclic loading for evaluation of lower-limb prostheses 双峰循环载荷对下肢假体的评价

IF 6.6 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-10-01 DOI: 10.1016/j.bbe.2025.10.004

Zhaokun Zhang , Wangrui Xu , Hanyu Gan , Chunlei K. Song , Albert J. Shih

Lower-limb prosthesis (LLP) is critical for the mobility and quality of life of amputees. Ensuring the reliability and durability of LLPs is essential to users’ safety, comfort, and mobility. While the current standard (ISO 10328) for the mechanical test of LLPs has served as a foundation, the sinusoidal cyclic loading method used for fatigue testing does not replicate the actual loading conditions on LLPs during a human walking gait. In normal walking, LLPs are subjected to a dual-peak loading condition with two distinct force peaks at the heel-strike and toe-off phases. Such a cyclic and dual-peak dynamic loading pattern on LLP is essential to test the durability of the LLP effectively and reliably. In this study, two simple and effective dual-peak cyclic loading test apparatuses are designed and built to evaluate the durability and functionality of LLPs. Two loading plates are used to contact the heel and toe of the prosthetic foot to simulate the dual-peak heel-strike and toe-off loadings between the foot and the ground. This dual-peak loading on the LLP is controlled and replicated by adjusting the positions of two loading plates and the actuator stroke to change the contact forces. Experimental results show that the proposed testing apparatuses and procedures can emulate the dual-peak axial loading of the LLP during normal walking gait, providing a more accurate testing method of the dynamic loading condition on LLPs than the current ISO standard.

下肢假肢（LLP）对截肢者的活动能力和生活质量至关重要。确保llp的可靠性和耐用性对用户的安全性、舒适性和移动性至关重要。虽然目前的llp力学测试标准（ISO 10328）已经作为基础，但用于疲劳测试的正弦循环加载方法并不能复制人类行走步态时llp的实际加载条件。在正常行走中，llp承受双峰加载条件，在脚跟撞击和脚趾撞击阶段有两个不同的力峰值。这种循环双峰动加载模式对于有效、可靠地测试LLP的耐久性至关重要。本研究设计并搭建了两台简单有效的双峰循环加载试验装置，以评估llp的耐久性和功能性。用两个加载板连接假肢脚的脚跟和脚趾，模拟脚与地面之间的双峰脚跟撞击和脚趾脱落载荷。通过调整两个加载板的位置和执行器行程来改变接触力，可以控制和复制LLP上的双峰载荷。实验结果表明，所提出的测试设备和程序能够模拟LLP在正常行走步态下的双峰轴向载荷，为LLP动态加载状况提供了比现行ISO标准更准确的测试方法。

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引用次数: 0

Design and development of a systematic validation protocol for synthetic melanoma images for responsible use in medical artificial intelligence 设计和开发用于医疗人工智能的合成黑色素瘤图像的系统验证协议

IF 6.6 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-09-21 DOI: 10.1016/j.bbe.2025.09.001

Alessio Luschi , Linda Tognetti , Alessandra Cartocci , Elisa Cinotti , Giovanni Rubegni , Laura Calabrese , Martina D’onghia , Martina Dragotto , Elvira Moscarella , Gabriella Brancaccio , Giulia Briatico , Camila Scharf , Dario Buononato , Vittorio Tancredi , Carmen Cantisani , Camilla Chello , Luca Ambrosio , Pietro Scribani Rossi , Marco Virone , Giovanni Pellacani , Ernesto Iadanza

Malignant melanoma is the deadliest form of skin cancer, and artificial intelligence could help address its diagnostic challenges. Generative Adversarial Networks (GANs) can generate synthetic dermoscopic images to augment limited real datasets, but the lack of standardised validation protocols holds back models’ reliability and clinicians’ trust. This study aims to design and develop a systematic validation protocol combining quantitative metrics and qualitative expert assessments to evaluate the realism, fidelity, diversity, and usefulness of synthetic dermoscopic melanoma images. A StyleGAN2 model, designed and trained in a previous study, was selected for its superior quantitative performance and exploited to generate 25 synthetic melanoma images, matched with 25 real images. A panel of 17 dermoscopists assessed the images using a 7-point Likert scale, across multiple qualitative attributes (real vs. synthetic, skin texture, visual realism, and confidence) and pattern analysis. Accuracy, sensitivity, specificity, Fleiss’ Kappa, and Krippendorff’s Alpha were calculated to analyse inter-rater agreement and evaluation outcomes. Accuracy in real vs synthetic images classification was moderate (64 %), with sensitivity at 73 % and specificity at 56 %, with poor inter-rater concordance over qualitative attributes. Synthetic images obtained superior scores in medium visual and overall realism, and confidence level, while the frequency of recognition of pigment network-patterns was comparable with real images. The proposed holistic validation protocol can effectively estimate the quality level of synthetic dermoscopic images, regardless of the architecture of the model used for generation, offering an objective and reliable evaluation tool, as qualitative evaluations remain crucial to ensure their safe deployment in clinical settings.

恶性黑色素瘤是最致命的皮肤癌，人工智能可以帮助解决其诊断挑战。生成对抗网络（GANs）可以生成合成的皮肤镜图像来增强有限的真实数据集，但缺乏标准化的验证协议阻碍了模型的可靠性和临床医生的信任。本研究旨在设计和开发一种结合定量指标和定性专家评估的系统验证方案，以评估合成皮肤镜下黑色素瘤图像的真实感、保真度、多样性和有用性。在之前的研究中设计和训练的StyleGAN2模型因其优越的定量性能而被选中，并利用它生成25张合成黑色素瘤图像，与25张真实图像相匹配。一个由17名皮肤科医生组成的小组使用7分李克特量表评估图像，包括多个定性属性（真实与合成、皮肤纹理、视觉真实感和信心）和模式分析。计算准确性、敏感性、特异性、Fleiss Kappa和Krippendorff Alpha来分析评分者之间的一致性和评估结果。真实图像与合成图像分类的准确率为中等（64%），灵敏度为73%，特异性为56%，定性属性间一致性较差。合成图像在中等视觉和整体真实感以及置信度方面得分较高，而对色素网络模式的识别频率与真实图像相当。所提出的整体验证方案可以有效地估计合成皮肤镜图像的质量水平，而不考虑用于生成的模型的架构，提供客观可靠的评估工具，因为定性评估对于确保其在临床环境中的安全部署至关重要。

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引用次数: 0

A wireless, implantable, dual-channel phrenic nerve stimulator for diaphragm pacing using electromagnetic resonance coupling 一种无线、可植入、双通道膈神经刺激器，用于使用电磁共振耦合的膈神经起搏

IF 6.6 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-08-30 DOI: 10.1016/j.bbe.2025.08.007

Xiaoyu Gu , Wei Zhong , Yan Shi , Meng Xu , Zhaohui Tong , Yixuan Wang

Objectives

Implantable diaphragm pacing (DP) system can effectively restore patients’ breathing.

Conventional diaphragm pacemakers have some practical limitations, such as transmission stability and high price. This study proposes an innovative, wirelessly powered dual-channel and inexpensive DP system to overcome some of these constraints.

Methods

The system realizes wireless power supply based on electromagnetic resonance coupling to improve stability. It comprised an external controller, two off-body transmitters and two in-vivo rectifier-integrated receivers. PCB spiral coils are used for energy transmission in wireless systems to ensure system stability and convenient processing. Receiver encapsulated with biocompatible PDMS convert received power into electrical stimulation energy. Stimulation waveform, multi-media environment and animal experimental tests were conducted to validate system’s performance. Specific absorption rate (SAR) in human tissue was calculated to confirm safety of implantation.

Results

Electrical stimulation parameters of the proposed DP system can be precisely adjusted. The stimulation amplitude range is 3–12 V with 0.1 V step resolution. Pulse width and frequency are adjustable from 100-300 µs and 10–100 Hz respectively. The breathing cycle and inhalation time can also be set individually. Wireless energy transmission has wide transmission distance (＞14 mm), good anti-offset capability (horizontal offset＞8mm) and implantation safety (SAR＜1.6 W/kg). Further time series of stimulation signals issued by the two channels are synchronized. The developed system effectively realizes respiratory response of animals to bilateral phrenic nerve stimulation with 17 mm wireless energy transmission distance and implantation of two receivers in vivo.

Conclusion

Our work provides a new optimization scheme for the design of implantable diaphragm pacemaker.

目的植入式膈肌起搏（DP）系统能有效恢复患者的呼吸。传统的膜片起搏器在实际应用中存在传输不稳定、价格昂贵等局限性。本研究提出了一种创新的、无线供电的双通道和廉价的DP系统来克服这些限制。方法实现基于电磁谐振耦合的无线供电，提高系统的稳定性。它包括一个外部控制器，两个离体发射器和两个体内整流集成接收器。无线系统中的能量传输采用PCB螺旋线圈，保证了系统的稳定性和处理的便捷性。用生物相容性PDMS封装的接收器将接收的功率转换为电刺激能量。通过刺激波形、多媒体环境和动物实验验证了系统的性能。计算人体组织的比吸收率（SAR）以确认植入的安全性。结果所提出的DP系统的电刺激参数可精确调节。刺激幅度范围为3 ~ 12v，步进分辨率为0.1 V。脉冲宽度和频率分别在100-300µs和10-100 Hz范围内可调。呼吸周期和吸入时间也可以单独设置。无线能量传输具有传输距离宽（> 14mm）、抗偏移能力好（水平偏移>8mm）和植入安全性（SAR<1.6 W/kg）等优点。两个通道发出的刺激信号的进一步时间序列是同步的。该系统通过17毫米无线能量传输距离，在体内植入两个接收器，有效地实现了动物对双侧膈神经刺激的呼吸反应。结论本工作为植入式隔膜起搏器的优化设计提供了一种新的方案。

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引用次数: 0

TRI-based heart rate variability parameterisation: advancing autonomic dysfunction assessment in diabetes and aging—A cross-sectional observational study 基于三自由度的心率变异性参数化：推进糖尿病和衰老的自主神经功能障碍评估——一项横断面观察研究

IF 6.6 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-08-29 DOI: 10.1016/j.bbe.2025.08.006

Shanglin Yang , Yuyang Lin , Xuwei Liao , Jianjung Chen , Hsientsai Wu

This cross-sectional observational study introduces the T-R interval (TRI), a novel electrocardiographic parameter designed to improve heart rate variability (HRV) assessment in ageing and diabetic populations. Defined as the R-R interval (RRI) minus the heart rate-corrected RT interval (RTc), TRI incorporates both depolarisation and repolarisation phases of the cardiac cycle, thereby offering deeper insights into autonomic function. A total of 126 participants, including 58 individuals with type 2 diabetes mellitus and 68 healthy controls, were assessed using conventional HRV indices. These included the low-to-high frequency power ratio (LHR), the short-to-long variability ratio (SSR), and the baroreflex entropy index (BEI), all of which were calculated from both RRI and TRI data. TRI-based indices demonstrated superior sensitivity in detecting autonomic dysfunction. Significant group differences were observed for TRI-derived MSE_LS (mean difference = 0.205, 95 % CI: 0.093–0.317, p = 0.036), SSR (mean difference = − 0.083, 95 % CI: −0.136–−0.029, p = 0.051), and BEI (mean difference = 0.205, 95 % CI: 0.093–0.318, p = 0.002), while their RRI-based equivalents did not reach statistical significance. ROC curve analysis showed improvements in the area under the curve (AUC) when TRI was used as the input parameter, with gains of 5.9 % for MSE_LS, 10.6 %for SSR, and 6.1 % for BEI. Logistic regression further identified TRI-based BEI as a protective factor against new-onset T2DM (OR = 0.058; 95 % CI: 0.009–0.378; p = 0.003). These findings suggest that TRI improves the diagnostic performance of HRV analysis and may support earlier detection of autonomic dysfunction, especially in clinical and wearable monitoring settings.

这项横断面观察性研究引入了T-R间隔（TRI），这是一种新的心电图参数，旨在改善老年人和糖尿病人群的心率变异性（HRV）评估。TRI被定义为R-R间期（RRI）减去心率校正后的RT间期（RTc），它结合了心脏周期的去极化和复极化阶段，从而对自主神经功能提供了更深入的了解。共有126名参与者，包括58名2型糖尿病患者和68名健康对照者，使用常规HRV指数进行评估。其中低高频功率比（LHR）、短长变异性比（SSR）和气压反射熵指数（BEI）均由RRI和TRI数据计算得到。基于tri的指数在检测自主神经功能障碍方面表现出更高的灵敏度。tri衍生的MSELS（平均差异= 0.205,95% CI: 0.093-0.317, p = 0.036）、SSR（平均差异= - 0.083,95% CI: - 0.136 - - 0.029, p = 0.051）和BEI（平均差异= 0.205,95% CI: 0.093-0.318, p = 0.002）组间差异显著，而基于rri的等效性差异无统计学意义。ROC曲线分析显示，以TRI作为输入参数时，MSELS、SSR和BEI的曲线下面积（AUC）分别增加了5.9%、10.6%和6.1%。Logistic回归进一步确定基于三因素的BEI是预防新发T2DM的保护因素（OR = 0.058; 95% CI: 0.009-0.378; p = 0.003）。这些发现表明，TRI提高了HRV分析的诊断性能，并可能支持自主神经功能障碍的早期检测，特别是在临床和可穿戴监测设置中。

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引用次数: 0

Lumbar intervertebral disc biomechanics: Geometry and collagen fiber orientation configurations effects 腰椎间盘生物力学：几何和胶原纤维取向构型的影响

IF 5.3 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-07-01 DOI: 10.1016/j.bbe.2025.07.003

Zhongwei Sun , Jiabao Pan , Weishi Liang , Changwen Mi , Peng Yin

This study proposes a probabilistic biphasic-swelling parameterized finite element framework, with the aim of which is to systematically evaluate the impact of lumbar intervertebral disc (L-IVD) geometry and annulus fibrosus collagen fiber configuration on multi-axial biomechanical behavior. Thirty anatomical L-IVD geometric sets were sampled via Latin hypercube sampling of clinical anatomical variations. Three annulus fibrosus layer-wise fiber configurations were implemented: Constant

30^{\circ}

, Circumferential variation (

25^{\circ} - - 45^{\circ}

), and Circumferential-radial variation (

23^{\circ} - - 50^{\circ}

). Consequently, the construction of three groups, comprising a total of ninety biphasic L-IVD finite element models, was undertaken. Five loading protocols were then simulated to reveal the critical dependencies of L-IVD biomechanical behavior. A statistical comparative analysis was performed to evaluate the influence of disc geometries and orientation strategies. The findings demonstrated that fiber orientation configuration exerts a substantial influence on swelling responses, compression stiffness, and flexion stiffness (

p < . 050

). Disc height exhibited strong inverse correlations with intradiscal pressure (

r < - 0.80

,

p < . 001

) and compression stiffness (

r < - 0.85

,

p < . 001

). Anterior-posterior length emerged as the primary predictor of sagittal stiffness (flexion:

r > 0.70

; extension:

r > 0.75

) and torsional resistance (

r > 0.50

), linked to altered moment arm mechanics. The nucleus pulposus volume ratio moderately affected intradiscal pressure (

r > 0.30

,

p < . 05

) but showed negligible impact on segmental stiffness. This parametric modelling framework facilitates systematic investigation of L-IVD biomechanics across anatomical variations. Additionally, these findings advocate for microstructure-informed computational models to optimize personalized implant designs and biomechanical assessments.

本研究提出了一个概率双相肿胀参数化有限元框架，旨在系统评估腰椎间盘（L-IVD）几何形状和纤维环胶原纤维结构对多轴生物力学行为的影响。通过临床解剖变异的拉丁超立方体采样，对30个解剖L-IVD几何集进行采样。纤维环按纤维层的排列有三种：恒定的30°、圆周变化（25°- 45°）和圆周径向变化（23°- 50°）。因此，进行了三组，包括共90个双相L-IVD有限元模型的构建。然后模拟五种加载方案，以揭示L-IVD生物力学行为的关键依赖关系。我们进行了统计比较分析，以评估椎间盘几何形状和定位策略的影响。研究结果表明，纤维取向结构对膨胀响应、压缩刚度和弯曲刚度有实质性影响（p< 0.050）。椎间盘高度与椎间盘内压力（r< - 0.80, p<.001）和压缩刚度（r< - 0.85, p<.001）呈强烈的负相关。前后长度是矢状位刚度的主要预测因子(屈曲：r>；0.70；延伸：r>；0.75)和扭转阻力（r>0.50），与改变的力臂力学有关。髓核体积比适度影响椎间盘内压力（r>0.30, p< 0.05），但对节段刚度的影响可以忽略不计。这种参数化建模框架有助于系统地研究跨解剖变异的L-IVD生物力学。此外，这些发现提倡微观结构的计算模型，以优化个性化的种植体设计和生物力学评估。

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引用次数: 0

Can cerebral autoregulation be monitored with non-linear correlation indices? A proof-of-concept study 非线性相关指标能否监测大脑自调节？概念验证研究

IF 5.3 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-07-01 DOI: 10.1016/j.bbe.2025.07.005

Karol Sawicki , Arkadiusz Syta , Pawel Dzienis , Lukasz Tymiński , Bartlomiej Ambrożkiewicz , Andrzej Koszewnik , Magdalena Maria Sawicka , Tomasz Łysoń , Zofia Czosnyka , Marek Czosnyka

Objective

Cerebral autoregulation (CA) is the mechanism by which cerebral vessels self-regulate blood flow to maintain adequate brain perfusion. Although CA monitoring is recommended in neurocritical care as a means to improve therapy, there is currently no consensus on the most effective computational technique. The aim of this study was to evaluate the feasibility of measuring CA using recurrence quantification analysis (RQA)—a non-linear method for analysing complex systems—as an alternative to traditional, linear correlation-based indices.

Methods

A retrospective analysis was conducted on a database of head-injured patients treated in a neurocritical care unit who developed spontaneous intracranial pressure (ICP) elevations known as plateau waves. Signals from arterial blood pressure, ICP, and cerebral blood flow velocity were segmented into stable phases of elevated ICP (associated with CA deterioration) and the preceding baseline. Non-linear RQA correlations were calculated for both periods, and the results were statistically compared. For reference, well-established linear CA indices were assessed in the same manner.

Results

The non-linear correlations followed a similar pattern to the linear CA indices and successfully differentiated the plateau wave phase with a comparable, high level of statistical significance (p < 0.0001), while demonstrating higher values and reduced data dispersion.

Conclusion

Non-linear RQA correlation is feasible for CA assessment. To the best of the authors’ knowledge, this is the first evaluation of RQA feasibility in CA research. In the pursuit of a reliable index suitable for widespread implementation in neurocritical care, a non-linear approach may offer a promising alternative to traditional linear correlation-based indices.

目的脑自调节（cerebral autoregulation， CA）是脑血管自我调节血流以维持脑灌注的机制。虽然CA监测被推荐用于神经危重症监护，作为改善治疗的一种手段，但目前对于最有效的计算技术还没有达成共识。本研究的目的是评估使用递归量化分析（RQA）（一种分析复杂系统的非线性方法）作为传统的基于线性相关指标的替代方法来测量CA的可行性。方法回顾性分析在神经危重症监护室治疗的出现自发性颅内压升高（高原波）的颅脑损伤患者的数据库。来自动脉血压、ICP和脑血流速度的信号被划分为ICP升高（与CA恶化相关）的稳定阶段和之前的基线。计算两个时期的非线性RQA相关性，并对结果进行统计学比较。作为参考，已建立的线性CA指数以相同的方式进行评估。结果非线性相关性遵循与线性CA指数相似的模式，并成功区分了高原波相位，具有相当的高水平统计学意义(p <；0.0001)，同时显示出更高的值和减少的数据分散。结论非线性RQA相关性评价CA是可行的。据作者所知，这是CA研究中首次对RQA可行性进行评估。在追求一个可靠的指标，适合在神经危重症护理的广泛实施，非线性的方法可能提供一个有希望的替代传统的线性相关为基础的指标。

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引用次数: 0

Movement and force dynamics in bimanual cooperative tasks in chronic stroke and healthy individuals 慢性脑卒中和健康人双手合作任务的运动和力动力学

IF 5.3 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-07-01 DOI: 10.1016/j.bbe.2025.07.002

J. Podobnik, M. Munih, M. Mihelj

Stroke rehabilitation often involves the use of haptic robots to improve motor control and bimanual coordination. This study examines how damping affects movement and force dynamics in bimanual tasks performed by healthy participants and participants with chronic stroke using a haptic robotic system equipped with force sensors for each hand. Participants completed tasks at three damping levels:

0 \frac{N}{m / s}

(no damping),

20 \frac{N}{m / s}

(low damping), and

40 \frac{N}{m / s}

(moderate damping). Key parameters for trajectory of movement, velocity, manipulation force, and internal force were analyzed to assess movement stability and control. The results revealed that damping

20 \frac{N}{m / s}

effectively stabilized movements in persons with stroke, reducing velocity deviations and making their performance more comparable to healthy participants, without introducing excessive resistance. In contrast, damping

40 \frac{N}{m / s}

acted as resistance training. Participants with stroke exhibited consistently higher internal forces than healthy participants, reflecting compensatory strategies and inefficient motor control. These findings demonstrate that low damping (

20 \frac{N}{m / s}

) offers an optimal balance between movement stabilization and resistance, highlighting its potential as a rehabilitation strategy, while moderate damping (

40 \frac{N}{m / s}

) may be reserved for resistance training.

中风康复通常涉及使用触觉机器人来改善运动控制和双手协调。本研究考察了阻尼如何影响健康参与者和慢性中风参与者在每只手配备力传感器的触觉机器人系统中进行的双手任务的运动和力动力学。参与者在三种阻尼水平下完成任务：0Nm/s（无阻尼）、20Nm/s（低阻尼）和40Nm/s（中等阻尼）。分析了运动轨迹、速度、操纵力和内力等关键参数，以评估运动稳定性和控制性。结果显示，20纳米/秒的阻尼有效地稳定了中风患者的运动，减少了速度偏差，使他们的表现更接近健康参与者，而不会产生过多的阻力。以40Nm/s阻尼作为阻力训练。卒中参与者表现出比健康参与者更高的内力，反映了代偿策略和低效的运动控制。这些研究结果表明，低阻尼（20Nm/s）在运动稳定和阻力之间提供了最佳平衡，突出了其作为康复策略的潜力，而中等阻尼（40Nm/s）可能保留用于阻力训练。

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引用次数: 0

Toward the integration of mixed reality and brain-computer interfaces based on code-modulated visual evoked potentials 基于码调制视觉诱发电位的混合现实与脑机接口集成研究

IF 5.3 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-07-01 DOI: 10.1016/j.bbe.2025.06.003

Selene Moreno-Calderón , Víctor Martínez-Cagigal , Ana Martín-Fernández , Eduardo Santamaría-Vázquez , Roberto Hornero

Background and objective: Brain-computer interface (BCI) systems can assist individuals with severe motor disabilities by enabling communication through their brain signals using spellers, which allow selecting commands from a set of options. For this technology, accuracy, speed and user comfort are essential. Code-modulated visual evoked potentials (c-VEPs) have demonstrated promising performance in BCI control. Integrating BCI systems with mixed reality (MR) could provide portability and autonomy. However, to the best of our knowledge, no existing studies have explored the feasibility of combining MR with c-VEP-based BCIs. This study aims to: (1) evaluate the performance of integrating MR with c-VEP-based BCIs and (2) study the visual fatigue induced by c-VEPs compared to traditional screen. Methods: Twenty participants used a 36-character speller to select words in both MR and traditional screen conditions. Metrics like accuracy and information transfer rate (ITR) were measured. Usability and eyestrain were evaluated through questionnaires. Results: The integration of MR with c-VEPs achieved an accuracy of 96.71 % and an ITR of 27.55 bits/min, compared to 95.98 % accuracy and 27.10 bits/min for the conventional screen condition. The questionnaires revealed minimal levels of visual fatigue in both conditions and high usability. No significant differences were observed between conditions in terms of performance or visual fatigue. Conclusions: The c-VEP-based speller with MR-BCI technology proved feasible, achieving performance levels similar to the conventional setup, with high accuracy in both conditions. The study also found comparable visual fatigue between MR and traditional screens, supporting the practicality of MR integration in BCI systems.

背景和目的：脑机接口（BCI）系统可以帮助患有严重运动障碍的人，通过使用拼写器使他们的大脑信号能够交流，从而允许从一组选项中选择命令。对于这项技术，准确性、速度和用户舒适度是必不可少的。编码调制视觉诱发电位（c-VEPs）在脑机接口控制中表现出良好的性能。将BCI系统与混合现实（MR）集成可以提供可移植性和自主性。然而，据我们所知，目前还没有研究探讨MR与基于c- vep的脑机接口联合的可行性。本研究旨在：(1)评价MR与基于c- vep的脑机接口集成的性能；(2)研究与传统屏幕相比，c- vep引起的视觉疲劳。方法：20名参与者使用36个字符的拼写器在MR和传统屏幕条件下选择单词。测量了准确性和信息传输率（ITR）等指标。通过问卷对可用性和眼疲劳进行评价。结果：MR与c-VEPs的整合准确率为96.71%，ITR为27.55 bits/min，而常规筛选条件下准确率为95.98%，ITR为27.10 bits/min。调查问卷显示，在两种情况下，视觉疲劳的程度都很低，可用性也很高。在表现或视觉疲劳方面，没有观察到明显的差异。结论：基于c- vep的拼写器与MR-BCI技术被证明是可行的，在两种情况下都具有较高的准确率，达到了与传统设置相似的性能水平。该研究还发现MR和传统屏幕的视觉疲劳程度相当，这支持了MR集成在脑机接口系统中的实用性。

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引用次数: 0

A potential approach to detecting of gastrointestinal slow waves based on optically pumped magnetometers array 一种基于光泵磁强计阵列的胃肠道慢波检测方法

IF 6.6 2区医学 Q1 ENGINEERING, BIOMEDICAL

Biocybernetics and Biomedical Engineering

Pub Date : 2025-07-01 DOI: 10.1016/j.bbe.2025.08.001

Yixiang Zhang , Xinlei He , Haoyue Li , Linke Zhang , Bing Yan , Yuming Peng , Qinggang Ge , Ming Ding , Yuxin Leng

Gastrointestinal slow wave (SW) can be used to evaluate human gastrointestinal function. Compared with electrogastrogram and electroenterogram, SW magnetic signals measurement can obtain higher-quality results. Optically pumped magnetometers (OPMs) based on the spin exchange relaxation-free method have comparable weak magnetic detection capabilities to superconducting quantum interference devices, and does not require liquid helium. Therefore, this study developed a gastrointestinal SW signals measurement system using OPM sensors. Our system measured rat intestinal SW signals with a frequency of approximately 34.24 cpm, and simultaneously extracted human gastric SW signals of approximately 3 cpm and intestinal SW signals of 8–12 cpm for the first time. It was also observed that the postprandial gastrointestinal SW signals were significantly enhanced compared with the fasting state. The results exhibited consistent power and time–frequency characteristics with previous reports. In summary, the gastrointestinal SW signals measurement system based on OPM provides a new technical approach for detecting gastrointestinal SWs and diagnosing related diseases.

胃肠慢波（SW）可用于评价人体胃肠功能。与胃电和肠电相比，SW磁信号测量可以获得更高质量的结果。基于自旋交换无弛豫方法的光泵磁强计（OPMs）具有与超导量子干涉装置相当的弱磁探测能力，并且不需要液氦。因此，本研究开发了一种利用OPM传感器的胃肠道SW信号测量系统。我们的系统测量了大鼠肠道SW信号，频率约为34.24 cpm，并首次同时提取了人类胃SW信号，频率约为3 cpm，肠道SW信号为8-12 cpm。与禁食状态相比，餐后胃肠道SW信号明显增强。结果显示出与先前报道一致的功率和时频特性。综上所述，基于OPM的胃肠道SW信号测量系统为检测胃肠道SW和诊断相关疾病提供了新的技术途径。

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引用次数: 0