AbstractIntroduction: Sleep Bruxism (SB) is a non-functional rhythmic movement of the mandible with multifactorial aetiology and complex diagnose. It has been the subject of various studies over the past decades and it is considered a result of actions of the Central Nervous System modulated by Autonomous Nervous System. In this work, we test the hypothesis that SB subjects present a typical and defined neurobehavioral pattern that can be distinct from that of non-bruxers subjects and can be measured during wakefulness. Methods Fifteen sleep bruxers (experimental-group EG) and fifteen non-bruxers (control-group CG) took part in the experiments. To verify the presence and severity of SB, clinical examinations, anamneses and questionnaires, including Visual Analogic Scale - faces (VAS-f) and State-Trait Anxiety Inventory (STAI) were applied. To legitimate the diagnoses of SB, a disposable instrument (Bitestrip®) to assess the masseter activity during sleep was employed. All subjects were submitted to a set of experiments for measuring various visual evoked responses during the presentation of visual stimuli (pleasant, unpleasant and neutral images). Events in Visual Evoked Potential (VEP) were used to compare the neural responses of both CG and EG. Results VAS-f showed EG with higher perception of stress than CG (trait: p=0.05), and lower quality of life for (state: p=0.007). STAI I and II showed significant differences of anxiety between CG and EG (p=0.013 and p=0.004, respectively), being EG the highest. The EG Bitestrip scores confirmed that 100% of subjects were sleep bruxers. Significant differences were found between EG and CG for events associated with emotional (pleasant and unpleasant) images in the first 250 ms after stimulation. In general, EG subjects showed higher amplitude and shorter latency of VEP events. Conclusion It is possible to distinguish between SB and non-bruxers subjects during wakefulness, based on differences in amplitude and latency of cortical event related potentials elicited by visual stimulation. SB subjects show greater amplitudes in specific events in frontal areas when non-pleasant images are shown. Latencies tend to be anticipated in SB compared to CG subjects.

Introduction: Individuals with mobility impairments associated with lower limb disabilities often face enormous challenges to participate in routine activities and to move around various environments. For many, the use of wheelchairs is paramount to provide mobility and social inclusion. Nevertheless, they still face a number of challenges to properly function in our society. Among the many difficulties, one in particular stands out: navigating in complex internal environments (indoors). The main objective of this work is to propose an architecture based on Mobile Augmented Reality to support the development of indoor navigation systems dedicated to wheelchair users, that is also capable of recording CAD drawings of the buildings and dealing with accessibility issues for that population. Methods Overall, five main functional requirements are proposed: the ability to allow for indoor navigation by means of Mobile Augmented Reality techniques; the capacity to register and configure building CAD drawings and the position of fiducial markers, points of interest and obstacles to be avoided by the wheelchair user; the capacity to find the best route for wheelchair indoor navigation, taking stairs and other obstacles into account; allow for the visualization of virtual directional arrows in the smartphone displays; and incorporate touch or voice commands to interact with the application. The architecture is proposed as a combination of four layers: User interface; Control; Service; and Infrastructure. A proof-of-concept application was developed and tests were performed with disable volunteers operating manual and electric wheelchairs. Results The application was implemented in Java for the Android operational system. A local database was used to store the test building CAD drawings and the position of fiducial markers and points of interest. The Android Augmented Reality library was used to implement Augmented Reality and the Blender open source library handled the basis for implementing directional navigation arrows. OpenGL ES provided support for various graphics and mathematical transformations for embedded systems, such as smartphones. Experiments were performed in an academic building with various labs, classrooms and male and female bathrooms. Two disable volunteers using wheelchairs showed no difficulties to interact with the application, either by entering touch or voice commands, and to navigate within the testing environment with the help of the navigational arrows implemented by the augmented reality modules. Conclusion The novel features implemented in the proposed architecture, with special emphasis on the use of Mobile Augmented Reality and the ability to identify the best routes free of potential hazards for wheelchair users, were capable of providing significant benefits for wheelchair indoor navigation when compared to current techniques described in the literature.

Introduction Decomposition of electromyography (EMG) signals into the constituent motor unit action potentials (MUAPs) can allow for deeper insights into the underlying processes associated with the neuromuscular system. The vast majority of the methods for EMG decomposition found in the literature depend on complex algorithms and specific instrumentation. As an attempt to contribute to solving these issues, we propose a method based on a bank of matched filters for the decomposition of EMG signals. Methods Four main units comprise our method: a bank of matched filters, a peak detector, a motor unit classifier and an overlapping resolution module. The system’s performance was evaluated with simulated and real EMG data. Classification accuracy was measured by comparing the responses of the system with known data from the simulator and with the annotations of a human expert. Results The results show that decomposition of non-overlapping MUAPs can be achieved with up to 99% accuracy for signals with up to 10 active motor units and a signal-to-noise ratio (SNR) of 10 dB. For overlapping MUAPs with up to 10 motor units per signal and a SNR of 20 dB, the technique allows for correct classification of approximately 71% of the MUAPs. The method is capable of processing, decomposing and classifying a 50 ms window of data in less than 5 ms using a standard desktop computer. Conclusion This article contributes to the ongoing research on EMG decomposition by describing a novel technique capable of delivering high rates of success by means of a fast algorithm, suggesting its possible use in future real-time embedded applications, such as myoelectric prostheses control and biofeedback systems.

Este artigo descreve o projeto de um sistema computacional em tempo real para biofeedback multimodal. As informações biológicas ou psico-fisiológicas do paciente são detectadas por sensores específicos e processadas para prover feedback visual, por meio de ambientes virtuais tridimensionais e feedback auditivo. O dispositivo foi projetado para coleta e tratamento de seis sinais distintos: EMG, EEG, GSR, temperatura, frequência cardíaca e frequência respiratória. O aplicativo de software foi projetado em linguagem Visual C++ e utiliza técnicas de programação concorrente para permitir o tratamento adequado de todas as ações em tempo real. Os ambientes virtuais foram criados no software 3D Studio Max® e renderizados utilizando os recursos da biblioteca gráfica DirectX® da Microsoft Corp. O sistema desenvolvido resultou, conforme relatos dos voluntários, em sessões agradáveis e interessantes, que permitiam a escolha de diferentes tipos de ambientes virtuais capazes de se adequar às necessidades individuais. Todos os dados coletados durante as sessões de biofeedback são armazenados em um banco de dados específico, possibilitando a geração de relatórios para o terapeuta e permitindo o acompanhamento da evolução dos pacientes ao longo do tratamento. O sistema possui potencialidade para utilização como apoio ao tratamento de diversas patologias e disfunções, como demonstrado pelos experimentos realizados nas diferentes modalidades de biofeedback. Com este trabalho, os autores esperam ainda contribuir para o desenvolvimento de know-how nacional na área, à medida que disponibilizam técnicas avançadas para produção de hardware e software aplicáveis a tratamentos em biofeedback multimodal.

This article describes the design of a real-time multimodal biofeedback system. Biological or psycho-physiological information from the patients are detected by specific sensors and processed to provide visual feedback, by means of three-dimensional virtual environments and auditory feedback. The device has been designed to capture up to six biomedical signals: EMG, EEG, GSR, temperature, heart rate and respiratory rate. The software was designed using Visual C++ and uses concurrent programming techniques to allow proper treatment of all actions in real time. The virtual environments have been created with 3D Studio Max® and rendered using the resources of the DirectX® graphics library from Microsoft Corp. The developed system resulted, according to reports from volunteers, in enjoyable and interesting sessions, allowing the selection of different types of virtual environments able to adapt to individual needs. All data collected during the biofeedback sessions are stored in a specific database, allowing the generation of reports to the therapist and enabling him to monitor the progress of the patients throughout the treatment. The system has great potential to be uses as a supporting tool for the treatment of various diseases and disorders, as demonstrated by experiments performed on different types of biofeedback. Also, with this work, the authors hope to contribute to the further development of national expertise in the area, as they provide advanced techniques for the production of hardware and software applied to multimodal biofeedback treatments.

A Engenharia Clínica é uma área com atuação nos Estabelecimentos Assistenciais de Saúde, desenvolvendo atividades baseadas nos conhecimentos de engenharia e de gerenciamento aplicadas às tecnologias de saúde. Nesse contexto, este trabalho relata os impactos econômicos da aplicação de técnicas de gestão em Engenharia Clínica num hospital público brasileiro de grande porte e referência em alta complexidade - Hospital de Clínicas da Universidade Federal de Uberlândia. Trata-se de uma pesquisa quantitativa, onde foram consideradas questões econômicas e de qualidade, suportada por pesquisa documental. O levantamento de dados baseou-se em relatórios e documentos administrativos do hospital do período de 2001 a 2010, referentes a recursos humanos, indicadores de serviços, indicadores de qualidade, custos com peças e contratos. Dentre os resultados encontrados, destaca-se a redução de aproximadamente 20% nas manutenções corretivas e sua estabilização ao longo do tempo, mesmo em face de um elevado aumento do parque tecnológico da instituição. No montante global de gastos com contratos, observou-se uma redução de cerca de 65% no período avaliado. A economia gerada pela gestão em Engenharia Clínica para a instituição foi de aproximadamente R$ 2 milhões em 2010, e a economia acumulada no período de 2001 a 2010 foi de R$ 7,6 milhões. Concluiu-se, que a gestão em Engenharia Clínica na instituição possibilitou uma redução significativa nos custos por meio da formação e capacitação de uma equipe própria, da redução dos custos com contratos e melhor planejamento das manutenções. Tais resultados demonstram a importância de um serviço de Engenharia Clínica para a melhor gestão de custos e das tecnologias em hospitais, sejam eles públicos ou privados.

Clinical Engineering is an important area for health care facilities, capable of applying engineering and management techniques to improve health technologies. In this context, this paper reports the economic impacts of the application of clinical engineering management techniques in a large Brazilian public hospital, which is also a reference for high complexity medical procedures - General Hospital of the Federal University of Uberlândia. The discussion is supported by a quantitative documentary research, which took into account not only the economic aspects, but also the quality of the service provided. The survey was based on reports and administrative documents from 2001 to 2010, related to human resources, service and quality indicators, costs of parts and contracts. Among the findings, it was observed a reduction of approximately 20% in corrective maintenance and their stabilization over time, even as the technological park of the institution increased. As for the overall amount of cost with contracts, there was a reduction of approximately 65% during the period. The savings generated by the Clinical Engineering Service, for the institution, were about R$ 2 million in 2010. The cumulative savings over the period of 2001 to 2010 were about R$ 7.6 million. Based on those results, it can be concluded that the Clinical Engineering Service provided a significant reduction in costs for the institution, by means of setting and training its own team, reducing costs and a better planning of maintenance. Those results demonstrate the importance of a Clinical Engineering Service for best managing costs and technologies in hospitals, whether public or private.