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1.
Sci Rep ; 14(1): 5878, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467735

RESUMEN

Assistive powered wheelchairs will bring patients and elderly the ability of remain mobile without the direct intervention from caregivers. Vital signs from users can be collected and analyzed remotely to allow better disease prevention and proactive management of health and chronic conditions. This research proposes an autonomous wheelchair prototype system integrated with biophysical sensors based on Internet of Thing (IoT). A powered wheelchair system was developed with three biophysical sensors to collect, transmit and analysis users' four vital signs to provide real-time feedback to users and clinicians. A user interface software embedded with the cloud artificial intelligence (AI) algorithms was developed for the data visualization and analysis. An improved data compression algorithm Minimalist, Adaptive and Streaming R-bit (O-MAS-R) was proposed to achieve a higher compression ratio with minimum 7.1%, maximum 45.25% compared with MAS algorithm during the data transmission. At the same time, the prototype wheelchair, accompanied with a smart-chair app, assimilates data from the onboard sensors and characteristics features within the surroundings in real-time to achieve the functions including obstruct laser scanning, autonomous localization, and point-to-point route planning and moving within a predefined area. In conclusion, the wheelchair prototype uses AI algorithms and navigation technology to help patients and elderly maintain their independent mobility and monitor their healthcare information in real-time.


Asunto(s)
Internet de las Cosas , Silla de Ruedas , Humanos , Anciano , Inteligencia Artificial , Algoritmos , Programas Informáticos , Diseño de Equipo
2.
Med Eng Phys ; 95: 39-44, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34479691

RESUMEN

RESEARCH QUESTION: Would there be differences in muscle activation between healthy subjects' (HS) dominant leg and transfemoral amputees' (TFA) intact-leg/contralateral-limb (IL) during normal transient-state walking speed? METHODS: The muscle activation patterns are obtained by calculating the linear envelope of the EMG signals for each group. The activation patterns/temporal changes are compared between-population using statistical parametric mapping (SPM). RESULTS: Individual muscle activity showed significant differences in all muscles except vastus lateralis (VL), semitendinosus (SEM) and tensor fascia latae (TFL) activities. SIGNIFICANCE: The information could be used by the therapists to prevent secondary physical conditions and prosthetic companies to improve the mobility of the amputees.


Asunto(s)
Amputados , Miembros Artificiales , Fenómenos Biomecánicos , Marcha , Humanos , Pierna , Caminata , Velocidad al Caminar
3.
Gait Posture ; 76: 98-103, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31751916

RESUMEN

BACKGROUND: Lower limb amputation is a major public health issue globally, and its prevalence is increasing significantly around the world. Previous studies on lower limb amputees showed analogous complexity implemented by the neurological system which does not depend on the level of amputation. RESEARCH QUESTION: What are the differences in muscle synergies between healthy subjects (HS) and transfemoral amputees (TFA) during self-selected normal transient-state walking speed? METHODS: thirteen male HS and eleven male TFA participated in this study. Surface electromyography (sEMG) data were collected from HS dominant leg and TFA intact limb. Concatenated non-negative matrix factorization (CNMF) was used to extract muscle synergy components synergy vectors (S) and activation coefficient profiles (C). Correlation between a pair of synergy vectors from HS and TFA was analyzed by means of the coefficient of determination (R2). Statistical parametric mapping (SPM) was used to compare the temporal components of the muscle synergies between groups. RESULTS: the highest correlation was perceived in synergy 2 (S2) and 3 (S3) and the lowest in synergy 1 (S1) and 4 (S4) between HS and TFA. Statistically significant differences were observed in all of the activation coefficients, particularly during the stance phase. Significant lag in the activation coefficient of S2 (due mainly to activated plantarflexors) resulted in a statistically larger portion of the gait cycle (GC) in stance phase in TFA. SIGNIFICANCE: Understanding the activation patterns of lower limb amputees' muscles that control their intact leg (IL) and prosthetic leg (PL) joints could lead to greater knowledge of neuromuscular compensation strategies in amputees. Studying the low-dimensional muscle synergy patterns in the lower limbs can further this understanding. The findings in this study could contribute to improving gait rehabilitation of lower limb amputees and development of the new generation of prostheses.


Asunto(s)
Amputación Quirúrgica , Miembros Artificiales , Fémur/cirugía , Músculo Esquelético/fisiología , Velocidad al Caminar , Adulto , Amputados/rehabilitación , Fenómenos Biomecánicos , Estudios de Casos y Controles , Electromiografía , Femenino , Marcha/fisiología , Humanos , Masculino , Persona de Mediana Edad
5.
Biomed Res Int ; 2016: 5435397, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27652264

RESUMEN

Currently, researchers turn to natural processes such as using biological microorganisms in order to develop reliable and ecofriendly methods for the synthesis of metallic nanoparticles. In this study, we have investigated extracellular biosynthesis of silver nanoparticles using four Aspergillus species including A. fumigatus, A. clavatus, A. niger, and A. flavus. We have also analyzed nitrate reductase activity in the studied species in order to determine the probable role of this enzyme in the biosynthesis of silver nanoparticles. The formation of silver nanoparticles in the cell filtrates was confirmed by the passage of laser light, change in the color of cell filtrates, absorption peak at 430 nm in UV-Vis spectra, and atomic force microscopy (AFM). There was a logical relationship between the efficiencies of studied Aspergillus species in the production of silver nanoparticles and their nitrate reductase activity. A. fumigatus as the most efficient species showed the highest nitrate reductase activity among the studied species while A. flavus exhibited the lowest capacity in the biosynthesis of silver nanoparticles which was in accord with its low nitrate reductase activity. The present study showed that Aspergillus species had potential for the biosynthesis of silver nanoparticles depending on their nitrate reductase activity.


Asunto(s)
Aspergillus/química , Nanopartículas del Metal/química , Plata/química
6.
J Craniomaxillofac Surg ; 43(7): 1072-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26116310

RESUMEN

OBJECTIVES: To assess heat generation in osteotomies during application of sonic and ultrasonic saws compared to conventional bur. METHODS: Two glass-fiber isolated nickel-chromium thermocouples, connected to a recording device, were inserted into fresh bovine rib bone blocks and kept in 20 ± 0.5 °C water at determined depths of 1.5 mm (cortical layer) and 7 mm (cancellous layer) and 1.0 mm away from the planned osteotomy site. Handpieces, angulated 24-32°, were mounted in a vertical drill stand, and standardized weights were attached to their tops to exert loads of 5, 8, 15 and 20 N. Irrigation volumes of 20, 50 and 80 ml/min were used for each load. Ten repetitions were conducted using new tips each time for each test condition. The Mann-Whitney-U test was used for statistical analysis (p < 0.05). RESULTS: Both ultrasonic and sonic osteotomies were associated with significantly lower heat generation than conventional osteotomy (p < 0.01). Sonic osteotomy showed non-significantly lower heat generation than ultrasonic osteotomy. Generated heat never exceeded the critical limit of 47 °C in any system. Variation of load had no effect on heat generation in both bone layers for all tested systems. An increased irrigation volume resulted in lower temperatures in both cortical and cancellous bone layers during all tested osteotomies. CONCLUSION: Although none of the systems under the conditions of the present study resulted in critical heat generation, the application of ultrasonic and sonic osteotomy systems was associated with lower heat generation compared to the conventional saw osteotomy. Copious irrigation seems to play a critical role in preventing heat generation in the osteotomy site.


Asunto(s)
Temperatura Corporal/fisiología , Huesos/fisiología , Osteotomía/instrumentación , Piezocirugía/instrumentación , Procedimientos Quirúrgicos Ultrasónicos/instrumentación , Animales , Hueso Esponjoso/fisiología , Hueso Esponjoso/cirugía , Bovinos , Hueso Cortical/fisiología , Hueso Cortical/cirugía , Calor , Costillas/fisiología , Costillas/cirugía , Estrés Mecánico , Irrigación Terapéutica/métodos , Termómetros
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