This paper describes a semi-powered ankle prosthesis and corresponding unified controller that provides biomimetic behavior for level and sloped walking without requiring identification of ground slope or modulation of control parameters. The controller is based on the observation that healthy individuals maintain an invariant external quasi-stiffness (spring like behavior between the shank and ground) when walking on level and sloped terrain. Emulating an invariant external quasi-stiffness requires an ankle that can vary the set-point (i.e., equilibrium angle) of the ankle stiffness. A semi-powered ankle prosthesis that incorporates a novel constant-volume power-asymmetric actuator was developed to provide this behavior, and the unified controller was implemented on it. The device and unified controller were assessed on three subjects with transtibial amputations while walking on inclines, level ground, and declines. Experimental results suggest that the prosthesis and accompanying controller can provide a consistent external quasi-stiffness similar to healthy subjects across all tested ground slopes.
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http://dx.doi.org/10.1109/TNSRE.2021.3049194 | DOI Listing |
Nat Commun
January 2025
School of Biological Science and Medical Engineering & School of Engineering Medicine, Beihang University, Beijing, China.
Urinary proteomics is emerging as a potent tool for detecting sensitive and non-invasive biomarkers. At present, the comparability of urinary proteomics data across diverse liquid chromatography-mass spectrometry (LC-MS) platforms remains an area that requires investigation. In this study, we conduct a comprehensive evaluation of urinary proteome across multiple LC-MS platforms.
View Article and Find Full Text PDFBMC Infect Dis
January 2025
Department of Epidemiology and Health Statistics, School of Public Health, Fujian Medical University, Fuzhou, China.
Background: The prognostic value of Chlamydia pneumoniae (Cpn) infection in postoperative lung cancer patients remains unclear. This study aimed to evaluate the association between Cpn infection and survival in lung cancer patients.
Methods: This study included 309 newly diagnosed primary lung cancer patients from three hospitals in Fuzhou, China.
Nutrients
January 2025
Department of Nutritional Sciences, College of Health and Human Sciences, Texas Tech University, Lubbock, TX 79409, USA.
Background: Malnutrition remains a significant public health issue in Kenya. Multisectoral Nutrition Governance (MNG) is increasingly being acknowledged as a catalyst for enhancing nutrition programming and outcomes. Effective MNG establishes policies, systems, and mechanisms that enable coordinated, adequately funded, and sustainable nutrition actions across sectors; however, its understanding and progress assessment remain inadequate.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Department of Automation, "Dunarea de Jos" University of Galati, 800008 Galati, Romania.
This paper deals with a "digital twin" (DT) approach for processing, reprocessing, and scrapping (P/R/S) technology running on a modular production system (MPS) assisted by a mobile cyber-physical robotic system (MCPRS). The main hardware architecture consists of four line-shaped workstations (WSs), a wheeled mobile robot (WMR) equipped with a robotic manipulator (RM) and a mobile visual servoing system (MVSS) mounted on the end effector. The system architecture integrates a hierarchical control system where each of the four WSs, in the MPS, is controlled by a Programable Logic Controller (PLC), all connected via Profibus DP to a central PLC.
View Article and Find Full Text PDFThe integration of large-scale power electronic equipment has intensified harmonic issues in power systems. Accurate harmonic models are fundamental for evaluating and mitigating harmonic problems, but existing models still exhibit deficiencies in harmonic mechanism, model complexity and accuracy. This work proposes a calculation method of crossed frequency admittance matrix (CFAM) analytical model based on piecewise linearization, aiming to achieve accurate modeling of phase-controlled power electronic harmonic sources.
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