Real-time torque estimation using human and sensor data fusion for exoskeleton assistance

Robotic assistive devices have emerged as a potential complement for repeti-tive and user-centered gait rehabilitation. In this field, the development of electromyography (EMG)-based torque controls has played a crucial role in improving the user experience with robotic assistive devices. However, most existing approaches for EMG-based joint torque estimation (i) are designed for upper limbs; (ii) often do not consider the complexity of the walking mo-tion, focusing only on the stance phase; and (iii) rely on complex mathemat-ical models that result in time-consuming estimations. This study aims to address these shortcomings by evaluating the generalization ability of a Deep Learning regressor (Convolutional Neural Network (CNN)) for estimating ankle torque trajectories, in real-time. Several inputs were incorporated, namely, EMG signals from Tibialis Anterior and Gastrocnemius Lateralis, hip kinematic data in the sagittal plane (angle, angular velocity, angular acceler-ation), walking speed (from 1.5 to 2.0 km/h), user's demographic (gender and age) and anthropometric information (height and mass, ranging from 1.50 to 1.90 m and 50.0 to 90.0 kg, respectively, and shank and foot lengths). Re-sults showed that a CNN model with two convolutional layers showed the highest generalization ability (Root Mean Square Error: 23.4±8.36, Normal-ized Mean Square Error: 0.494±0.299, and Spearman Correlation 0.754±0.105). CNN model’s time-effectiveness was tested in an active ankle orthosis, being able to estimate ankle joint torques in less than 2 millisec-onds. This study contributes to a more time-effective model for real-time EMG-based torque estimation, enabling a promising advancement in EMG-based torque control for lower limb robotic assistive devices.This work was funded by the Fundação para a Ciência e Tecnologia under the scholarship reference 2020.05711.BD, under the Stimulus of Scientific Employment with the grant 2020.03393.CEECIND, with the FAIR project under grant 2022.05844.PTDC, under the national support to R&D units grant through the reference project UIDB/04436/2020 and UIDP/04436/2020, and under the scholarship reference POCI-01-0247-FEDER-039868_BI_04_2022_CMEMS

Para a noção de transformação curricular

Neste artigo é evidenciada a relação entre currículo e conhecimento, abordando-se o conhecimento escolar na sua seleção, organização e transformação, a partir de uma revisão do conceito de transposição didática e da proposição dos conceitos de transformação curricular e transformação didática. Qualquer debate sobre o currículo exige a dilucidação do conhecimento e uma reflexão sobre os seus diversos significados, sobretudo quando a educação se torna num projeto amplo de questionamento da realidade social. Para além de várias questões colocadas acerca do conhecimento escolar e do modo como a sua organização pode ser realizada, procura-se centrar o debate numa reflexão sobre as fronteiras entre conhecimentos e esclarecer que, sobre essa temática, jamais poderão existir respostas fechadas.This article highlights the link between curriculum and knowledge, the approach of school knowledge’s selection, organization and transformation is based on a revision of the concept of didactic transposition and on the proposal of the concepts of curriculum and didactic transformation. Debates on curriculum demand an explanation and a reflection on the multiple meanings of knowledge mainly when education aims to be a broad project to contest social reality. It aims to focus the discussion on a reflection regarding the borders between knowledges and to show that in this subject there are never closed answers.Dans cet article est mis en évidence le rapport entre le curriculum et la connaissance, en abordant la connaissance scolaire dans sa sélection, son organisation et sa transformation à partir d’une révision du concept de transposition didactique et de la proposition des concepts de transformation du curriculum et de transformation didactique. Toute discussion sur le curriculum exige la dilucidation de la connaissance et une réflexion sur ses plusieurs signifiés, surtout quand l’éducation devient un projet plus large de mise en question de la réalité sociale. Au delà des plusieurs questions posées autour de la connaissance scolaire et de la manière comme son organisation peut être réalisée, on cherche á fixer le débat dans une réflexion sur les frontières entre connaissances et éclaircir que, sur cette thématique jamais ne pourront exister des réponses absolues.En este trabajo se pone en evidencia la relación entre el currículum y el conocimiento, abordándose el conocimiento escolar en su selección, organización y transformación desde una revisión del concepto de transposición didáctica y de la proposición de los conceptos de transformación curricular y transformación didáctica. Cualquier discusión sobre el currículum requiere la aclaración del conocimiento y una reflexión sobre sus diversos significados, especialmente cuando la educación se convierte en un proyecto más amplio de cuestionamiento de la realidad social. Además de varias preguntas sobre el conocimiento escolar y el modo en el que su organización puede tener lugar, se intenta centrar el debate en una reflexión sobre las fronteras entre conocimientos y aclarar que en esta temática jamás podrán existir respuestas cerradas.(undefined

Acute exercise induce endothelial nitric oxide synthase phosphorylation via Akt and AMP-activated protein kinase in aorta of rats: Role of reactive oxygen species

AbstractBackgroundAcute exercise increases reactive oxygen species (ROS) levels, including hydrogen peroxide (H2O2). H2O2 promotes endothelial nitric oxide synthase (eNOS) activation and phosphorylation in endothelial cells. With this in mind, the present study was designed to evaluate ex vivo eNOS phosphorylation in rat aortas incubated with H2O2 and to test this hypothesis in vivo in the aortas of rats submitted to acute exercise.MethodsFor ex vivo studies, six groups of aortic tissue were formed: control, H2O2, N-acetylcysteine (NAC), LY294002, compound C, and LY294002 plus compound C. While incubation with H2O2 increased Akt, AMPK and eNOS phosphorylation, pre-incubation with NAC strongly reduced the phosphorylation of these enzymes. For in vivo studies, male Wistar rats were divided into four groups: control, cont+NAC, exercise, and exer+NAC. After a 3h swimming session, animals were decapitated and aortas were excised for biochemical and immunoblotting analysis.ResultsAcute exercise increased superoxide levels and dichlorofluorescein (DCF) concentrations, and this increase was related to phosphorylation of Akt, AMPK and eNOS. On the other hand, use of NAC reduced superoxide levels and DCF concentration. Reduced superoxide levels and DCF in the exer+NAC group were associated with decreased Akt, AMPK and eNOS phosphorylation. These results appear to be connected with vascular function because VASP phosphorylation increased in acute exercise and decreased in exer+NAC.ConclusionOur results indicate that ROS induced by acute exercise play the important role of activating eNOS, a process apparently mediated by Akt and AMPK

Prevention of hypertension in patients with pre-hypertension: protocol for the PREVER-prevention trial

<p>Abstract</p> <p>Background</p> <p>Blood pressure (BP) within pre-hypertensive levels confers higher cardiovascular risk and is an intermediate stage for full hypertension, which develops in an annual rate of 7 out of 100 individuals with 40 to 50 years of age. Non-drug interventions to prevent hypertension have had low effectiveness. In individuals with previous cardiovascular disease or diabetes, the use of BP-lowering agents reduces the incidence of major cardiovascular events. In the absence of higher baseline risk, the use of BP agents reduces the incidence of hypertension. The PREVER-prevention trial aims to investigate the efficacy, safety and feasibility of a population-based intervention to prevent the incidence of hypertension and the development of target-organ damage.</p> <p>Methods</p> <p>This is a randomized, double-blind, placebo-controlled clinical trial, with participants aged 30 to 70 years, with pre-hypertension. The trial arms will be chlorthalidone 12.5 mg plus amiloride 2.5 mg or identical placebo. The primary outcomes will be the incidence of hypertension, adverse events and development or worsening of microalbuminuria and of left ventricular hypertrophy in the EKG. The secondary outcomes will be fatal or non-fatal cardiovascular events: myocardial infarction, stroke, heart failure, evidence of new sub-clinical atherosclerosis, and sudden death. The study will last 18 months. The sample size was calculated on the basis of an incidence of hypertension of 14% in the control group, a size effect of 40%, power of 85% and P alpha of 5%, resulting in 625 participants per group. The project was approved by the Ethics committee of each participating institution.</p> <p>Discussion</p> <p>The early use of blood pressure-lowering drugs, particularly diuretics, which act on the main mechanism of blood pressure rising with age, may prevent cardiovascular events and the incidence of hypertension in individuals with hypertension. If this intervention shows to be effective and safe in a population-based perspective, it could be the basis for an innovative public health program to prevent hypertension in Brazil.</p> <p>Trial Registration</p> <p>Clinical Trials <a href="http://www.clinicaltrials.gov/ct2/show/NCT00970931">NCT00970931</a>.</p

Influence Of The Conditioning Factors Of Cardiac Transplant Patients To The Self-Care Engagement Profile

Background: This study aimed to identify the conditioning factors that influence the self-care practice of heart transplant patient after discharge and relate the conditioning factors to the Engagement Profile of Self Care. Methods: Cross-sectional study, undertaken at a transplantation unit of one public hospital, in Fortaleza-Ceará. There was the participation of 63 heart transplant patients. Results: The majority of the patients were men (88.9%), aged 40-59 years (68.3%), catholic (81.0%), married (77.8%), elementary school (71, 4%), retired or not working (82.5%); income below minimum wage (47, 6%); diagnosis to transplantation was chagasic cardiomyopathy (28.6%), post-transplant time between one and three years (39.7%). The determinant for self-care had significant difference (p&lt;0.05) was the time of transplantation, because patients who have higher scores on Engagement Profile Self-Care had performed transplantation between 3 and 5 years. Conclusion: The professional team of heart transplant should consider the conditioning factors of patients transplanted cardiac in establishing strategies for promoting self-care

Role of rutin in 5-Fluorouracil-induced intestinal mucositis : prevention of histological damage and reduction of inflammation and oxidative stress

Intestinal mucositis, characterized by inflammatory and/or ulcerative processes in the gastrointestinal tract, occurs due to cellular and tissue damage following treatment with 5-fluorouracil (5-FU). Rutin (RUT), a natural flavonoid extracted from Dimorphandra gardneriana, exhibits antioxidant, anti-inflammatory, cytoprotective, and gastroprotective properties. However, the effect of RUT on inflammatory processes in the intestine, especially on mucositis promoted by antineoplastic agents, has not yet been reported. In this study, we investigated the role of RUT on 5-FU-induced experimental intestinal mucositis. Swiss mice were randomly divided into seven groups: Saline, 5-FU, RUT-50, RUT-100, RUT-200, Celecoxib (CLX), and CLX + RUT-200 groups. The mice were weighed daily. After treatment, the animals were euthanized and segments of the small intestine were collected to evaluate histopathological alterations (morphometric analysis); malondialdehyde (MDA), myeloperoxidase (MPO), and glutathione (GSH) concentrations; mast and goblet cell counts; and cyclooxygenase-2 (COX-2) activity, as well as to perform immunohistochemical analyses. RUT treatment (200 mg/kg) prevented 5-FU-induced histopathological changes and reduced oxidative stress by decreasing MDA concentrations and increasing GSH concentrations. RUT attenuated the inflammatory response by decreasing MPO activity, intestinal mastocytosis, and COX-2 expression. These results suggest that the COX-2 pathway is one of the underlying protective mechanisms of RUT against 5-FU-induced intestinal mucositis

A list of land plants of Parque Nacional do Caparaó, Brazil, highlights the presence of sampling gaps within this protected area

Brazilian protected areas are essential for plant conservation in the Atlantic Forest domain, one of the 36 global biodiversity hotspots. A major challenge for improving conservation actions is to know the plant richness, protected by these areas. Online databases offer an accessible way to build plant species lists and to provide relevant information about biodiversity. A list of land plants of “Parque Nacional do Caparaó” (PNC) was previously built using online databases and published on the website "Catálogo de Plantas das Unidades de Conservação do Brasil." Here, we provide and discuss additional information about plant species richness, endemism and conservation in the PNC that could not be included in the List. We documented 1,791 species of land plants as occurring in PNC, of which 63 are cited as threatened (CR, EN or VU) by the Brazilian National Red List, seven as data deficient (DD) and five as priorities for conservation. Fifity-one species were possible new ocurrences for ES and MG states