Rio de Janeiro State University

About: Rio de Janeiro State University is a education organization based out in Rio de Janeiro, Brazil. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 16631 authors who have published 30919 publications receiving 465753 citations. The organization is also known as: UERJ & Rio de Janeiro State University.

Brain stimulation modulates the autonomic nervous system, rating of perceived exertion and performance during maximal exercise

Abstract: Background The temporal and insular cortex (TC, IC) have been associated with autonomic nervous system (ANS) control and the awareness of emotional feelings from the body. Evidence shows that the ANS and rating of perceived exertion (RPE) regulate exercise performance. Non-invasive brain stimulation can modulate the cortical area directly beneath the electrode related to ANS and RPE, but it could also affect subcortical areas by connection within the corticocortical neural networks. This study evaluated the effects of transcranial direct current stimulation (tDCS) over the TC on the ANS, RPE and performance during a maximal dynamic exercise. Methods Ten trained cyclists participated in this study (33±9 years; 171.5±5.8 cm; 72.8±9.5 kg; 10–11 training years). After 20-min of receiving either anodal tDCS applied over the left TC (T3) or sham stimulation, subjects completed a maximal incremental cycling exercise test. RPE, heart rate (HR) and R–R intervals (as a measure of ANS function) were recorded continuously throughout the tests. Peak power output (PPO) was recorded at the end of the tests. Results With anodal tDCS, PPO improved by ∼4% (anodal tDCS: 313.2±29.9 vs 301.0±19.8 watts: sham tDCS; p=0.043), parasympathetic vagal withdrawal was delayed (anodal tDCS: 147.5±53.3 vs 125.0±35.4 watts: sham tDCS; p=0.041) and HR was reduced at submaximal workloads. RPE also increased more slowly during exercise following anodal tDCS application, but maximal RPE and HR values were not affected by cortical stimulation. Conclusions The findings suggest that non-invasive brain stimulation over the TC modulates the ANS activity and the sensory perception of effort and exercise performance, indicating that the brain plays a crucial role in the exercise performance regulation.

Análise de Conteúdo e Análise do Discurso: aproximações e afastamentos na (re)construção de uma trajetória

Abstract: This paper focuses on the discussion of a discursive approach developped as an alternative to the insufficiencies of Content Analysis. Our goal in centered on two main questions: which are the insufficiencies which motivated a discursive approach; in what sense the practices in Content Analysis contributed to the positions assumed by a discursive approach. The conclusions indicate the need of further research on the unsettled relationship between text and context.

Observer reliability of three-dimensional cephalometric landmark identification on cone-beam computerized tomography

Abstract: Objective To evaluate reliability in 3-dimensional (3D) landmark identification using cone-beam computerized tomography (CBCT). Study design Twelve presurgery CBCTs were randomly selected from 159 orthognathic surgery patients. Three observers independently repeated 3 times the identification of 30 landmarks in the sagittal, coronal, and axial slices. A mixed-effects analysis of variance model estimated the intraclass correlations (ICC) and assessed systematic bias. Results The ICC was >0.9 for 86% of intraobserver assessments and 66% of interobserver assessments. Only 1% of intraobserver and 3% of interobserver coefficients were Conclusion Overall, the intra- and interobserver reliability was excellent. Three-dimensional landmark identification using CBCT can offer consistent and reproducible data if a protocol for operator training and calibration is followed. This is particularly important for landmarks not easily specified in all 3 planes of space.