Individuals with an above-knee (AK) amputation typically use passive prostheses, whether reactive (microprocessor) or purely mechanical. Though sufficient for walking, these solutions lack the positive power generation observed in able-bodied individuals. Active (powered) prostheses can provide positive power but suffer complex control and limited energy storage capacities. These shortcomings motivate the development of an active prosthesis implementing a novel impedance controller design with energy regeneration. The controller requires only five tuning parameters that are intuitive to adjust in contrast to the current standard-finite state machine impedance scheduling of up to 45 gains. This simplification is uniquely achieved by modulating knee joint impedance by axial shank force. Furthermore, the proposed control approach introduces analytical guidance for impedance tuning to purposely integrate energy regeneration; specifically, a precise amount of negative damping is injected into the joint. A pilot study conducted with a volunteer with an AK amputation walking at three distinct speeds and at continually self-selected varying speeds demonstrated the adaptability of the controller to changes in speed. Self-powered operation was attained for all trials despite low mechanical component efficiencies. These early results suggest the efficacy of simplifying impedance control tuning and fusing control and energy regeneration in transfemoral prostheses.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.medengphy.2021.103744 | DOI Listing |
ACS Appl Bio Mater
January 2025
Advanced Magnetic Materials Research Center, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, North Kargar Street, Tehran 11155-4563, Iran.
Although 3D printing is becoming a dominant technique for scaffold preparation in bone tissue engineering (TE), developing hydrogel-based ink compositions with bioactive and self-healing properties remains a challenge. This research focuses on developing a bone scaffold based on a composite hydrogel, which maintains its self-healing properties after incorporating bioactive glass and is 3D-printable. The plain hydrogel ink was synthesized using natural polymers of 1 wt % N-carboxyethyl chitosan, 2 wt % hyaluronic acid aldehyde, 0.
View Article and Find Full Text PDFCell Commun Signal
January 2025
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, China.
Autophagy is essential for maintaining material balance and energy circulation and plays a critical role as a regulatory mechanism in tissue regeneration. However, current studies primarily describe this phenotype, with limited exploration of its molecular mechanisms. In this study, we provided the first evidence that autophagy is required for intestinal regeneration in Apostichopus japonicus and identified a previously unrecognized regulatory mechanism involved in this process.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Department of Physics, Faculty of Science, King Abdulaziz University, 21589, Jeddah, Saudi Arabia.
A sustainable biosorbent, silver nanoparticles-decorated coffee-ground waste (CWAg), was synthesized through a simple in-situ reduction method. CWAg is extensively characterized via SEM-EDX, PZC, FTIR, XRD, HR-TEM, and XPS analyses. The biosorbent was tested to remove chromium (Cr(VI)) and methylene blue (MB) from wastewater, and its antibacterial properties was evaluated.
View Article and Find Full Text PDFPLoS Pathog
January 2025
Department of Respiratory Medicine, Center for Pathogen Biology and Infectious Diseases, Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, China.
Hypervirulent Klebsiella pneumoniae (hvKP) poses an alarming threat in clinical settings and global public health owing to its high pathogenicity, epidemic success and rapid development of drug resistance, especially the emergence of carbapenem-resistant lineages (CR-hvKP). With the decline of the "last resort" antibiotic class and the decreasing efficacy of first-line antibiotics, innovative alternative therapeutics are urgently needed. Capsule, an essential virulence determinant, is a major cause of the enhanced pathogenicity of hvKP and represents an attractive drug target to prevent the devastating clinical outcomes caused by hvKP infection.
View Article and Find Full Text PDFPLoS One
January 2025
School of Civil Engineering and Transportation, Weifang University, Weifang, China.
As the foundation and cornerstone of the digital economy, digital infrastructure construction is an indispensable engine for realizing China's energy-saving and emission-reduction, innovation-driven and low-carbon transformation and development. Investigating the carbon unlocking effect of digital infrastructure construction might hasten the achievement of the dual-carbon goal and the "win-win" scenario of environmental protection and economic growth. However, there is still a gap between whether and how digital infrastructure construction can break the carbon lock-in (CLI).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!