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1.
Critical limb ischemia (CLI) constitutes the most severe form of peripheral arterial disease (PAD), it is characterized by progressive blockade of arterial vessels, commonly correlated to atherosclerosis. Currently, revascularization strategies (bypass grafting, angioplasty) remain the first option for CLI patients, although less than 45% of them are eligible for surgical intervention mainly due to associated comorbidities. Moreover, patients usually require amputation in the short-term. Angiogenic cell therapy has arisen as a promising alternative for these “no-option” patients, with many studies demonstrating the potential of stem cells to enhance revascularization by promoting vessel formation and blood flow recovery in ischemic tissues. Herein, we provide an overview of studies focused on the use of angiogenic cell therapies in CLI in the last years, from approaches testing different cell types in animal/pre-clinical models of CLI, to the clinical trials currently under evaluation. Furthermore, recent alternatives related to stem cell therapies such as the use of secretomes, exosomes, or even microRNA, will be also described.  相似文献   
2.
The oil palm industry is one of the important sectors in Malaysia. The growth and development of this industry shows that Malaysia is the world second-largest oil palm producers. However, in the fresh fruit bunch (FFB) harvesting process, the harvesters are exposed to many types of work-related musculoskeletal disorders (WMSDs). The FFB harvesters tend to develop WMSDs especially the shoulders and trunk. Hence, it is important to identify the exposure levels, awkward postures and the reaction forces of muscle activity based on the posture and movement of the harvesters when using pole, chisel and loading spike during the harvesting process. The objective of this study was to investigate the effect of the design of oil palm FFB harvesting tools on WMSDs of the upper body. Rapid Upper Limb Analysis (RULA) was used to investigate and assess the exposure level on the harvester body during the harvesting process. The assessment showed that the shoulders and trunk have high exposure level and undergo awkward posture. Human Musculoskeletal Model Analysis (HMMA) was used to identify the reaction force exerted on the muscle during the FFB harvesting process. In this study, 4 muscles were analysed including Triceps, Biceps, Erector Spinae and Psoas Major. The highest reaction force of 16.36 N was found on the left triceps when handling a loading spike. In conclusion, it is important to address the risks by reviewing all possible aspects that contribute to the WMSDs and interventions on the tool design, task and working shifts may be required.  相似文献   
3.
针对现有外骨骼机器人人机自由度不匹配和关节对中性差的问题,提出欠驱动下肢康复机器人. 欠驱动机器人只有4个直线驱动,驱动的直线运动通过推杆和人机连接机构转化为人下肢在矢状面内的屈伸运动,带动人体进行步态康复训练. 建立机器人系统的人机耦合模型,进行模型的动力学分析,对人机耦合模型中影响动力学结果的参数进行分析,建立驱动力与肢体推动力之间的关系模型,并以推力系数最大为目标进行参数分析与优化,得到最佳的结构参数. 根据优化后的结构参数搭建康复机器人实验系统,对髋、膝关节驱动力与角度进行对比. 实验结果表明最大髋关节角度误差为2.9°,最大膝关节角度误差为6.4°,最大误差均约为9%,验证了动力学模型和参数优化结果的正确性.  相似文献   
4.
In PSA Peugeot Citroen factories, high precision requirements of workstations make them being manual. One of the main goal of the car manufacturer is to minimize the pain of workers while maintaining high efficiency of production lines. Consequently, assisting operators with an exoskeleton is a potential solution for improving ergonomics of painful workstations while respecting industrial constraints. To determine ergonomic performances of an exoskeleton, human joint angles and torques, ground reaction forces, and duration of operations are analysed for eight subjects performing a representative screwing task. Experiments were performed using ABLE upper-limb exoskeleton, developed by the French Atomic Energy Commission (CEA), which has the functionality to compensate arm and tools loads. Results show a clear reduction of the sum of the joints torques, up to 38.9%, given by ABLE supply and invite to make concrete the use of exoskeletons in car assembly lines.  相似文献   
5.
针对拟型服务机器人在家庭环境中的自主抓取任务,提出了一种强调运动姿态似人特性的机器人手臂动作的运动规划方法.该方法基于人体工程学中的快速上肢评估准则评价机器人运动姿态的似人特性,并在此基础上以机器人传速速率最优为目标规划机器人持物动作的姿态构型.最后以Motoman SDA10D拟人双臂机器人为例,具体介绍了该方法的应用和规划的结果,规划结果证明了该方法的可行性和有效性.  相似文献   
6.
Many modeled and observed data are in coarse resolution, which are required to be downscaled. This study develops a probabilistic method to downscale 3-hourly runoff to hourly resolution. Hourly data recorded at the Poldokhtar Stream gauge (Karkheh River basin, Iran) during flood events (2009–2019) are divided into two groups including calibration and validation. Statistical tests including Chi-Square and Kolmogorov–Smirnov test indicate that the Burr distribution is proper distribution functions for rising and falling limbs of the floods’ hydrograph in calibration (2009–2013). A conditional ascending/descending random sampling from the constructed distributions on rising/falling limb is applied to produce hourly runoff. The hourly-downscaled runoff is rescaled based on observation to adjust mean three-hourly data. To evaluate the efficiency of the developed method, statistical measures including root mean square error, Nash–Sutcliffe efficiency, Kolmogorov-Smirnov, and correlation are used to assess the performance of the downscaling method not only in calibration but also in validation (2014–2019). Results show that the hourly downscaled runoff is in close agreement with observations in both calibration and validation periods. In addition, cumulative distribution functions of the downscaled runoff closely follow the observed ones in rising and falling limb in two periods. Although the performance of many statistical downscaling methods decreases in extreme values, the developed model performs well at different quantiles (less and more frequent values). This developed method that can properly downscale other hydroclimatological variables at any time and location is useful to provide high-resolution inputs to drive other models. Furthermore, high-resolution data are required for valid and reliable analysis, risk assessment, and management plans.  相似文献   
7.
社会老龄化进程中,由于疾病或事故导致下肢受损的患者越来越多,患者的运动能力康复变得尤为重要.相对于传统的物理康复治疗方法,利用下肢康复机器人进行运功功能康复训练可以准确评估、大幅改善康复效果,提高康复效率,节约医疗康复资源.作为一种涉及康复医学、机械学、控制学、机器人学、计算机学及人工智能等诸多学科的智能仿生机电设备,下肢康复机器人按照患者的康复作业姿态主要分为坐卧式下肢康复机器人和站立式下肢康复机器人.其中坐卧式下肢康复机器人可以分为脚踏板式和外骨骼式机器人,站立式下肢康复机器人分为悬挂减重式和独立可穿戴式机器人.本文调研了国际上应用较为广泛的几类下肢康复机器人的代表性产品,详细分析了下肢康复机器人的主被动自由度、驱动方式、传动关节、感知技术、运动控制策略和训练模式等关键技术,并对各类机器人典型临床测试案例进行了比较和探讨,对下肢康复机器人未来的技术发展做出展望.  相似文献   
8.
文章论述了并联机床各分支链的运动约束对运动平台自由度的影响,提出了主动链和约束链的概念.在此基础上讨论了如何根据并联机床的自由度要求,确定约束链机构和各主动链运动副型式的问题.并结合几种实际并联机床构型,验证了该设计模型的正确性.  相似文献   
9.
随着现代科学技术的迅猛发展,外科手术经历了革命性变革,外科技术的核心之一是要达到术眼无血的效果。如今,止血技术已由过去单纯的器械止血发展为现代外科条件下的纷繁复杂的技术体系。本文提出了一种基于单片机的肢体手术止血控制系统实现方案,并详细介绍了系统的软硬件电路设计。系统可应用于肢体手术的止血环节,可以达到术眼无血的效果。  相似文献   
10.
For people with upper limb disabilities visual art is an important activity that allows for expression of individuality and independence. They show remarkable endurance, patience and determination to adapt their remaining capabilities to create visual art. There are significant advantages of digital technologies in assisting artists with upper limb disabilities. Paralinguistic voice recognition technologies have proven to be a particularly promising mode of interaction. Despite these benefits, technological support for people with upper limb disabilities to create visual art is scarce. This paper reports on a number of case studies of several artists with upper limb disabilities. These case studies illustrate the struggles they face to be creative and also show the significant advantages of digital technologies in assisting such artists. An investigation into people’s ability to use the volume of their voice to control cursor movement to create drawings on the screen is also reported. With motivation, training and practise, use of volume to control drawing tasks shows great promise. It is believed that paralinguistic voice has wider implications beyond assisting artists with upper limb disabilities, such as: an alternative mode of interaction for disabled people to perform tasks other than creating visual art, alternative mode of interaction for hands busy environments and as a voice training system for people with speech impairments.  相似文献   
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