519 research outputs found
Principle design of an energy efficient transfemoral prosthesis
In the pursuit of realizing an energy efficient transfemoral prosthetic, in this paper we present a preliminary study on a principle design. In particular, the design is based on the idea that the efficiency of the system can be realized by energetically coupling the knee and the ankle joints. In order to allow the energy transfer during the normal walking, we propose to introduce continuous controllable springs, which basically act as passive actuators
Mechanical design and control of a new myoelectric hand prosthesis
The development of modern, myoelectrically controlled hand prostheses can be difficult, due to the many requirements its mechanical design and control system need to fulfill [1]. The hand should be controllable with few input signals, while being able to perform a wide range of motions. It should be lightweight and slim, but be able to actuate all fingers separately. To accomplish this, new control and mechanical design techniques are implemented in a modern hand prosthesis prototype
Conceptual design of an energy efficient transfemoral prosthesis
In this study, we present the conceptual design of a fully-passive transfemoral prosthesis. The design is inspired by the power flow in human gait in order to have an energy efficient device. The working principle of the conceptual mechanism is based on three storage elements, which are responsible of the energetic coupling between the knee and the ankle joints. Design parameters of the prosthesis have been determined according to the energy absorption intervals of the human gait. Simulation results shows that the power flow of the system is comparable with human data. Finally, an initial prototype is presented as proof of concept
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Electronic Health Record-Based Surveillance for Community Transmitted COVID-19 in the Emergency Department
Introduction: SARS-CoV-2, a novel coronavirus, manifests as a respiratory syndrome (COVID-19) and is the cause of an ongoing pandemic. The response to COVID-19 in the United States has been hampered by an overall lack of diagnostic testing capacity. To address uncertainty about ongoing levels of SARS-CoV-2 community transmission early in the pandemic, we aimed to develop a surveillance tool using readily available emergency department (ED) operations data extracted from the electronic health record (EHR). This involved optimizing the identification of acute respiratory infection (ARI)-related encounters and then comparing metrics for these encounters before and after the confirmation of SARS-CoV-2 community transmission.Methods: We performed an observational study using operational EHR data from two Midwest EDs with a combined annual census of over 80,000. Data were collected three weeks before and after the first confirmed case of local SARS-CoV-2 community transmission. To optimize capture of ARI cases, we compared various metrics including chief complaint, discharge diagnoses, and ARI-related orders. Operational metrics for ARI cases, including volume, pathogen identification, and illness severity, were compared between the pre- and post-community transmission timeframes using chi-square tests of independence.Results: Compared to our combined definition of ARI, chief complaint, discharge diagnoses, and isolation orders individually identified less than half of the cases. Respiratory pathogen testing was the top performing individual ARI definition but still only identified 72.2% of cases. From the pre to post periods, we observed significant increases in ED volumes due to ARI and ARI cases without identified pathogen.Conclusion: Certain methods for identifying ARI cases in the ED may be inadequate and multiple criteria should be used to optimize capture. In the absence of widely available SARS-CoV-2 testing, operational metrics for ARI-related encounters, especially the proportion of cases involving negative pathogen testing, are useful indicators for active surveillance of potential COVID-19 related ED visits
Evaluating the clinical effects of a dynamic shoulder orthosis
Background: Shoulder orthoses reduce the gravitational pull on the shoulder by providing an upward force to the arm, which can decrease shoulder pain caused by stress on the glenohumeral structures.Objective: In this interventional study, the clinical effects of a recently developed dynamic shoulder orthosis were assessed in 10 patients with chronic shoulder pain. The shoulder orthosis provides an upward force to the arm with 2 elastic bands. These bands are arranged to statically balance the arm, such that the supportive force is always directed toward the glenohumeral joint and shoulder movements are not impeded.Study design: Clinical effect study.Methods: The study population was provided with a dynamic shoulder orthosis for 2 weeks. In the week before the orthosis fitting, the participants had no intervention. The primary outcome measures were the mean shoulder pain scores before and during the intervention, and the distance between the humeral head and the acromion without and with orthosis.Results: Ultrasound evaluation showed that the shoulder orthosis resulted in a reduction of the distance between the acromion and humeral head at different levels of arm support. In addition, it was demonstrated that the mean shoulder pain scores (range 0–10) decreased from 3.6 to 3 (in rest) and from 5.3 to 4.2 (during activities) after 2 weeks of orthosis use. In general, patients were satisfied with the weight, safety, ease in adjusting, and effectiveness of the orthosis.Conclusions: The results of this study show that the orthosis has the potential to reduce shoulder complaints in patients with chronic shoulder pain
Design and feasibility of the T-GRIP thumb exoskeleton to support the lateral pinch grasp of spinal cord injury patients
Pressão arterial de 24 horas em mulheres idosas normotensas e com hipertensão do avental branco
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