IEEE transactions on medical robotics and bionics最新文献_第5页

The Effect of User Learning for Online EEG Decoding of Upper-Limb Movement Intention 用户学习对上肢运动意向在线脑电解码的影响

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-31 DOI: 10.1109/TMRB.2025.3537663

Matteo Ceradini;Stefano Tortora;Silvestro Micera;Luca Tonin

{"title":"The Effect of User Learning for Online EEG Decoding of Upper-Limb Movement Intention","authors":"Matteo Ceradini;Stefano Tortora;Silvestro Micera;Luca Tonin","doi":"10.1109/TMRB.2025.3537663","DOIUrl":"https://doi.org/10.1109/TMRB.2025.3537663","url":null,"abstract":"Electroencephalography (EEG) based brain-computer interfaces (BCIs) offer a promising way for individuals with motor impairments to control prosthetic or rehabilitation devices. Accurately decoding movement intention (MI) is crucial for translating subjects’ motor execution plans into action. Common challenges in EEG-based BCIs include performance discrepancies, often requiring frequent recalibration of decoding algorithms. The objective of this study was enhancing BCI decoding performance of upper-limb MI identification by exploiting both machine and subjects’ learning and maintaining stable decoding algorithms. Significant performance improvements were observed across most subjects from the first to the last session of the experiment. Some subjects also demonstrated stable performance without requiring any model recalibration between sessions. All subjects achieved high efficacy in online decoding of movement intention, as reflected in improvement of the F1 score from <inline-formula> <tex-math>$0.58pm 0.26$ </tex-math></inline-formula> in the first session, to <inline-formula> <tex-math>$0.84pm 0.13$ </tex-math></inline-formula> in the final session. We emphasize the critical importance of allowing users sufficient time to improve their performance in BCIs for upper-limb MI decoding. Unlike existing studies, we specifically evaluate the effect of stable decoding strategies in online and longitudinal BCI sessions, which are key to achieving more reliable and effective BCIs.","PeriodicalId":73318,"journal":{"name":"IEEE transactions on medical robotics and bionics","volume":"7 2","pages":"633-641"},"PeriodicalIF":3.4,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10869338","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144084736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Selecting Muscles for Detection of Upper-Limb Compensatory Movements Using s-EMG Sensors 利用 s-EMG 传感器选择用于检测上肢补偿运动的肌肉

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-20 DOI: 10.1109/TMRB.2025.3531015

Mahshad Berjis;Marie-Eve LeBel;Daniel J. Lizotte;Ana Luisa Trejos

{"title":"Selecting Muscles for Detection of Upper-Limb Compensatory Movements Using s-EMG Sensors","authors":"Mahshad Berjis;Marie-Eve LeBel;Daniel J. Lizotte;Ana Luisa Trejos","doi":"10.1109/TMRB.2025.3531015","DOIUrl":"https://doi.org/10.1109/TMRB.2025.3531015","url":null,"abstract":"Patients with upper-limb injuries often use compensatory movements to overcome limitations in range of motion, which can lead to additional injury if not corrected early within a rehabilitation program. Although automatic detection of compensatory movements has been studied in the literature, the impact of sensor locations on detection performance has not been previously explored. To investigate how sensor locations affect the ability to automatically detect compensatory movements of the upper limb, sixteen surface electromyography sensors were placed on key muscles involved in these movements. Thirty-one healthy participants performed a door-opening task in three conditions: without elbow restrictions (healthy pattern), and two conditions with limited elbow range of motion (60° of flexion-full flexion and 30°–80° of flexion to simulate injury). Statistical analyses identified sensor locations with significant differences between the conditions. Support vector machine classifiers demonstrated notably higher performance using data from six sensors on the middle deltoid, the upper trapezius, the latissimus dorsi, the external obliques, and the erector abdominis. This study highlights the importance of thoughtful muscle selection for effective automatic detection and correction of upper-limb compensatory movements, which is crucial for a wearable mechatronic device to be effective in improving the movement quality of patients.","PeriodicalId":73318,"journal":{"name":"IEEE transactions on medical robotics and bionics","volume":"7 1","pages":"164-170"},"PeriodicalIF":3.4,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Study of Dexterous Hand Manipulation: A Synergy-Based Complexity Index 灵巧手部操作研究：基于协同作用的复杂性指数

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-17 DOI: 10.1109/TMRB.2025.3531006

A. Michael West;Federico Tessari;Margaret Wang;Neville Hogan

引用次数: 0

Magnetorheological-Elastomer-Based and Hydraulically Steerable Actuator for Micro Guidewire and Catheter 基于磁流变弹性体的微导丝和导管液压驱动装置

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-13 DOI: 10.1109/TMRB.2025.3527718

Min Sung Kim;Chan Young Park;Doo Yong Lee

{"title":"Magnetorheological-Elastomer-Based and Hydraulically Steerable Actuator for Micro Guidewire and Catheter","authors":"Min Sung Kim;Chan Young Park;Doo Yong Lee","doi":"10.1109/TMRB.2025.3527718","DOIUrl":"https://doi.org/10.1109/TMRB.2025.3527718","url":null,"abstract":"The pressure-driven mechanisms for steerable guidewires and catheters are difficult to fabricate when miniaturized to submillimeter-scale. Micro bubbles resulting from molding or surface irregularities due to surface tension can affect the actuation performance as the outer diameter of the pressure-driven actuator decreases to the submillimeter-scale. This paper presents a novel fabrication method to manufacture pressure-driven actuators of submillimeter-scale. The proposed fabrication method utilizes magnetorheological (MR) elastomer and magnetic field to determine the geometric dimensions of the actuator with micro-scale precision. An actuator of the diameter of 0.7 mm and the eccentricity of <inline-formula> <tex-math>$80~mu $ </tex-math></inline-formula>m is designed and fabricated with absolute errors of <inline-formula> <tex-math>$12~mu $ </tex-math></inline-formula>m and <inline-formula> <tex-math>$3~mu $ </tex-math></inline-formula>m, respectively. The steering performance of the fabricated micro actuator is tested through experiments. The actuator can achieve a sharp bending angle of 124 degrees with a length of 5.41 mm, by optimizing the eccentricity through the finite-element analysis.","PeriodicalId":73318,"journal":{"name":"IEEE transactions on medical robotics and bionics","volume":"7 1","pages":"77-84"},"PeriodicalIF":3.4,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Preliminary Evaluation of a Soft Wearable Robot for Shoulder Movement Assistance 柔性可穿戴肩部运动辅助机器人的初步评价

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-09 DOI: 10.1109/TMRB.2025.3527708

Lorenzo Campioni;Gianluca Dimonte;Giorgia Sciarrone;Gabriele Righi;Conor Walsh;Marta Gandolla;Giulio Del Popolo;Silvestro Micera;Tommaso Proietti

{"title":"Preliminary Evaluation of a Soft Wearable Robot for Shoulder Movement Assistance","authors":"Lorenzo Campioni;Gianluca Dimonte;Giorgia Sciarrone;Gabriele Righi;Conor Walsh;Marta Gandolla;Giulio Del Popolo;Silvestro Micera;Tommaso Proietti","doi":"10.1109/TMRB.2025.3527708","DOIUrl":"https://doi.org/10.1109/TMRB.2025.3527708","url":null,"abstract":"Spinal cord injuries (SCI) often lead to upper limb impairment, necessitating innovative solutions for daily assistance beyond traditional rigid robotics due to their impractical weight and size. Despite still preliminary, soft wearables are arising as a possible solution to fill this gap. Here, we demonstrated an enhanced version of a soft inflatable robot that assists the shoulder against gravity, previously tested with different neurological conditions. Noteworthy improvements include a single-layer actuator, simplifying manufacturing, a built-in bending angle and a nylon hammock, for better armpit conformity. We characterized the actuator (approximately <inline-formula> <tex-math>$8 Nm$ </tex-math></inline-formula> at 90° at <inline-formula> <tex-math>$70 kPa$ </tex-math></inline-formula>) and demonstrated its good transparency, both from a kinematic and a muscular standpoint. Then, on 11 healthy individuals, we showed reductions in shoulder muscle activity (both at the anterior and middle deltoid) while performing a lift and hold task, ranging from 16% to almost 60% of the maximum voluntary contraction. More importantly, we confirmed these effects on two SCI individuals SCI, at two different stages of recovery. While preliminary, considering the limited exploration of soft wearable robots for the shoulder in SCI cases, this is a significant advancement playing an important role in the development of future soft technology for SCI assistance.","PeriodicalId":73318,"journal":{"name":"IEEE transactions on medical robotics and bionics","volume":"7 1","pages":"315-324"},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10835215","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Accelerated Gradient-Based Neuroadaptive Synchronization Control for Antagonistic PAM Robot Hands With Obstacle Avoidance and Motion Constraints 具有避障和运动约束的对抗性PAM机械手加速梯度神经自适应同步控制

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-09 DOI: 10.1109/TMRB.2025.3527695

Tong Yang;Yuexuan Xu;Yongchun Fang;David Navarro-Alarcon;Song Men;Ning Sun

{"title":"Accelerated Gradient-Based Neuroadaptive Synchronization Control for Antagonistic PAM Robot Hands With Obstacle Avoidance and Motion Constraints","authors":"Tong Yang;Yuexuan Xu;Yongchun Fang;David Navarro-Alarcon;Song Men;Ning Sun","doi":"10.1109/TMRB.2025.3527695","DOIUrl":"https://doi.org/10.1109/TMRB.2025.3527695","url":null,"abstract":"Multiple pneumatic artificial muscles (PAMs) connected through antagonistic joints are more in line with the motion characteristics of human muscles, which better imitate/replace humans to complete a series of actual tasks, such as transportation and assembly. However, there is still a lack of comprehensive solutions to handle hysteresis, creep, input delay, and other inherent characteristics of PAMs, as well as synchronous control and obstacle avoidance that are important to multiple muscles working together. To this end, this paper proposes a new neuroadaptive synchronization controller for 3-D antagonistic PAM-actuated robot hands, which also elaborately designs auxiliary terms to realize obstacle avoidance in Cartesian space and motion constraints in joint space together. Here, dynamic obstacles are regarded as external independent objects, whose nonlinear dynamics are introduced into the proposed controller to restrict end-effectors. Meanwhile, the constraint terms of joint angles and angle velocities are designed as time-varying proportional-differential gains, instead of common barrier functions that may induce overlarge inputs. Particularly, this paper proposes an accelerated gradient-based learning term to relax the linear parameterization condition of uncertain/unmodeled dynamics and obtain accurate weight estimates, based on which, it is proven that both tracking errors and synchronous errors rapidly converge to zero. In addition to complete theoretical analysis, some hardware experiments also verify the effectiveness and adaptability of the proposed controller.","PeriodicalId":73318,"journal":{"name":"IEEE transactions on medical robotics and bionics","volume":"7 1","pages":"377-391"},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Design and Mechanics of Active Needles: A Review 活性针的设计与力学研究进展

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-09 DOI: 10.1109/TMRB.2025.3527705

Sujin Yu;Yuri Lim;Soomin Kim;Seok Chang Ryu

{"title":"Design and Mechanics of Active Needles: A Review","authors":"Sujin Yu;Yuri Lim;Soomin Kim;Seok Chang Ryu","doi":"10.1109/TMRB.2025.3527705","DOIUrl":"https://doi.org/10.1109/TMRB.2025.3527705","url":null,"abstract":"Steerable needles have been extensively studied in the medical robotics society for the past two decades, evolving from passive needles to active ones that enable independent motion at their distal tip via robotics technology. Extensive design and actuation options have been proposed for the more capable active needles, followed by a few studies on their path-planning and control techniques; however, no commercial systems are available for the clinical environment yet despite their clear benefit, i.e., improved steerability and versatility compared to the other existing types of needles. This paper reviews the state-of-the-art steerable needle studies to identify research gaps and aims to deepen understanding the mechanics of active needles in soft tissue, which is critical for design optimization, precise control, and preoperative planning but currently remains unclear. To simplify the analysis, this review suggests separating the mechanics of an active needle into two parts: one for each of the tip and the shaft, where the shaft can be understood similarly to the passive needle whose mechanics has been thoroughly studied compared to the active one. Therefore, investigating the tip mechanics, including tissue properties, tip loadings, and tip kinematics, can lead to the complete understanding of active needle mechanics, the next challenges.","PeriodicalId":73318,"journal":{"name":"IEEE transactions on medical robotics and bionics","volume":"7 1","pages":"189-199"},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Robotic Bronchoscopy System With Variable-Stiffness Catheter for Pulmonary Lesion Biopsy 可变刚度导管机器人支气管镜系统用于肺病变活检

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-09 DOI: 10.1109/TMRB.2025.3527655

Xing-Yu Chen;Wenjie Lai;Xiaohui Xiong;Xuemiao Wang;Shi-Mei Wang;Peng Li;Weiyi Han;Yangyang Du;Wenke Duan;Wenjing Du;Soo Jay Phee;Lei Wang

{"title":"Robotic Bronchoscopy System With Variable-Stiffness Catheter for Pulmonary Lesion Biopsy","authors":"Xing-Yu Chen;Wenjie Lai;Xiaohui Xiong;Xuemiao Wang;Shi-Mei Wang;Peng Li;Weiyi Han;Yangyang Du;Wenke Duan;Wenjing Du;Soo Jay Phee;Lei Wang","doi":"10.1109/TMRB.2025.3527655","DOIUrl":"https://doi.org/10.1109/TMRB.2025.3527655","url":null,"abstract":"Bronchoscopy is a minimally invasive and effective method for early lung cancer diagnosis. Traditional bronchoscopy faces challenges such as limited dexterity, operator fatigue, and difficulty in maintaining steady manipulation. Existing robot-assisted methods have deficiencies, such as tool instability due to the dynamic respiratory environment. This paper presents a teleoperated robotic bronchoscopy system, featuring a controllable variable-stiffness catheter that enhances stability and flexibility during transbronchial biopsies. The 7 DoF robotic system allows for translation, rotation, and bending of the bronchoscope; delivery and bending of the catheter; delivery and control of biopsy tools; as well as stiffness adjustment of the catheter, which adapts to the dynamic pulmonary environment to provide stable support during tissue sampling. Key contributions include the robotic platform integrated with the variable-stiffness catheter and the implementation of a novel three-stage procedure for tissue sampling. The robotic system has been thoroughly evaluated through a series of tests, including the system accuracy, characterization of the variable-stiffness catheter’s flexibility, force exertion, safety during operation, temperature control, and in-vivo experiment. The results demonstrated the system’s feasibility and effectiveness, with metrics such as safe force limits, system flexibility, and positioning accuracy, showing its potential to improve the accuracy and safety of traditional bronchoscopy procedures.","PeriodicalId":73318,"journal":{"name":"IEEE transactions on medical robotics and bionics","volume":"7 1","pages":"416-427"},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A High-Fidelity Simulation Framework for Grasping Stability Analysis in Human Casualty Manipulation 人体伤亡操纵中抓取稳定性分析的高保真仿真框架

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-09 DOI: 10.1109/TMRB.2025.3527687

Qianwen Zhao;Rajarshi Roy;Chad Spurlock;Kevin Lister;Long Wang

{"title":"A High-Fidelity Simulation Framework for Grasping Stability Analysis in Human Casualty Manipulation","authors":"Qianwen Zhao;Rajarshi Roy;Chad Spurlock;Kevin Lister;Long Wang","doi":"10.1109/TMRB.2025.3527687","DOIUrl":"https://doi.org/10.1109/TMRB.2025.3527687","url":null,"abstract":"Recently, there has been a growing interest in rescue robots due to their vital role in addressing emergency scenarios and providing crucial assistance in challenging or hazardous situations where human intervention is problematic. However, very few of these robots are capable of actively engaging with humans and undertaking physical manipulation tasks. This limitation is largely attributed to the absence of tools that can realistically simulate physical interactions, especially the contact mechanisms between a robotic gripper and a human body. In this study, we aim to address key limitations in current developments towards robotic casualty manipulation. Firstly, we present an integrative simulation framework for casualty manipulation. We adapt a finite element method (FEM) tool into the grasping and manipulation scenario, and the developed framework can provide accurate biomechanical reactions resulting from manipulation. Secondly, we conduct a detailed assessment of grasping stability during casualty grasping and manipulation simulations. To validate the necessity and superior performance of the proposed high-fidelity simulation framework, we conducted a qualitative and quantitative comparison of grasping stability analyses between the proposed framework and the state-of-the-art multi-body physics simulations. Through these efforts, we have taken the first step towards a feasible solution for robotic casualty manipulation.","PeriodicalId":73318,"journal":{"name":"IEEE transactions on medical robotics and bionics","volume":"7 1","pages":"281-289"},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Novel Deployable and Stiffness-Variable Homecare Hyper-Redundant Robot Based on the Origami Mechanism 基于折纸机制的新型可部署且刚度可变的家庭护理超冗余机器人

IF 3.4

IEEE transactions on medical robotics and bionics Pub Date : 2025-01-09 DOI: 10.1109/TMRB.2025.3527713

Zhenhua Gong;Guangpu Zhu;Ting Zhang

{"title":"A Novel Deployable and Stiffness-Variable Homecare Hyper-Redundant Robot Based on the Origami Mechanism","authors":"Zhenhua Gong;Guangpu Zhu;Ting Zhang","doi":"10.1109/TMRB.2025.3527713","DOIUrl":"https://doi.org/10.1109/TMRB.2025.3527713","url":null,"abstract":"The advantages of hyper-redundant robots lie in their natural flexibility and large deformation, as well as their passive adaptive ability, which shows great potential in medical and nursing applications. However, this feature also makes them weak in scalability and load capacity, making it difficult to complete fine care operations and daily grasping tasks. In this paper, a large deploy/fold ratio variable stiffness hyper-redundant robot based on the origami principle is proposed, which has a large deploy/fold ratio, and realizes large stiffness change based on the bionic muscle-driven variable stiffness principle. Based on the analysis of origami theory, the robot uses rigid origami mechanisms as the skeleton support, flexible gasbags as the backbones, and the hybrid actuation is used to realize the extension, contraction, variable stiffness, and omnidirectional bending motion. Based on the motion/stiffness model of the hyper-redundant robot, the characteristics of the single-joint and the 6-joint hyper-redundant robot are verified by experiments. These experiments confirm that the hyper-redundant robot has a large deploy/fold and variable stiffness range, obtains a large bending deformation and working range, can overcome the gravity generated by itself and the load, and has a high load capacity.","PeriodicalId":73318,"journal":{"name":"IEEE transactions on medical robotics and bionics","volume":"7 1","pages":"66-76"},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0