139 research outputs found
Exopolysaccharide production by Enterobacter A47: optimization of cultivation conditions and study of polymer functional properties
Dissertação para obtenção do Grau de Mestre em BiotecnologiaFucoPol is a fucose-containing biopolymer produced by the bacterium Gram-negative, Enterobacter A47 DSM 23139. It is an exopolysaccharide (EPS) composed of neutral sugars (fucose, galactose, glucose), an acidic sugar (glucuronic acid), and also non-saccharide substituents (acetate, pyruvate and succinate).
In this work, two primary objectives were considered: the optimization of EPS production by varying two different parameters, and the functional properties’ assessment of different EPS produced by the bacterium. In the optimization study, the influence of different dissolved oxygen concentrations (controlled at 10, 30 and 60% of air saturation), and the impact of phosphate concentration reduction in the culture medium (5.25 and 3.81 g L-1) were assessed. The objective was to evaluate not only the effect of both parameters on cellular growth and exopolysaccharide-synthesis, but also to determine their influence in EPS chemical composition. The best results were obtained with DO at 10%, with the highest EPS production (6.11 g L-1), and although a reduction of phosphate concentration didn’t affect the EPS production, it reduced the exopolysaccharide’s fucose content to 24%mol.
Secondly, the functional properties of nine distinct exopolysaccharides synthesized by Enterobacter A47 under different cultivation conditions were evaluated. Rheologically, most of the EPS polymer solutions showed shear-thinning behavior, wherein EPS-s, EPS-g and GNEX achieved the highest apparent viscosity (0.2 - 0.3 Pa.s) at lower shear rates (0.3 to 1 s-1). Also, most of the polymers presented emulsifying capacity at different temperatures. Concerning the film-forming capacity, EPS-s, EPS-g and EPS-x films demonstrated to have good mechanical properties and high water vapour permeability. And, all polymers described flocculating activity at 0.01% of EPS, which was significantly diminished at lower concentration, 0.001%
Biofeedback system to improve the human-orthosis interaction
Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Eletrónica Médica)Every year, 15 million people worldwide suffer a stroke. More than 80 % of stroke survivors present gait disabilities, limiting their motor independence and well-being. The patients may regain their motor independence with active orthoses. Biofeedback systems (BSs) may be used as an orthotic rehabilitation’s complementary tool to inform the user timely and objectively about their behaviour during gait. Thus, teaching the patients how to improve the human-orthosis interaction. Overall, this allows accelerating and increasing the effectiveness of the gait recovery. Nonetheless, there is a lack of BSs for orthotic gait rehabilitation, and no wearable solution is available.
This dissertation aims the development of a wearable, stand-alone and modular BS to be integrated into SmartOs-ankle orthosis, following a user-centered design. The developed BS provides sensory, sonorous, and visual stimulation through vibrotactile motors, headphones, and a Red-Green-Blue Light-Emitting Diode, respectively. The BS includes a microcontroller to manage the activation of the stimuli according to the interaction torque and the reference trajectory of the SmartOs-ankle orthosis. The sensory and sonorous stimuli were chosen for developing user-oriented strategies to teach the user, as follows. When and how to perform the paretic and non-paretic foot-floor contact (foot-floor contact biofeedback); the direction of ankle rotation along the gait cycle (joint motion biofeedback); and, the necessary muscular strength along with the gait cycle (user participation biofeedback). The visual stimulus is used to help the therapist to follow the performance of the patients during the therapy and, consequently, help and motivate them – therapist-oriented strategies.
From a validation with healthy subjects, the BS increased the user’s motor performance significantly when walking with an orthosis. The system was able to teach the users about the direction of ankle rotation and the necessary muscular strength along with the gait cycle, improving the human-orthosis interaction. Future work towards enhancing the foot-floor contact strategies and extending the BS validation with a large group of participants and longer training period.A cada ano, 15 milhões de pessoas, mundialmente, sofrem um acidente vascular cerebral (AVC). Mais de 80 % dos sobreviventes apresentam incapacidades de marcha, limitando a sua independência motora e bem-estar. Estes pacientes podem recuperar a sua independência motora através do uso de ortóteses ativas. Adicionalmente os sistemas de biofeedback (BSs) podem ser usados como uma ferramenta complementar da reabilitação assistida por ortótese, informando os usuários, oportunamente e objetivamente, acerca do seu comportamento durante a execução de uma tarefa, e ensinando-os a melhorar a sua interação com a ortótese; assim, acelerando e aumentando a eficácia da recuperação. Não obstante, existem poucos BSs desenvolvidos para a reabilitação assistida por ortóteses, os quais não são vestíveis.
Esta dissertação tem como objetivo o desenvolvimento de um BS vestível, autónomo e modular para ser integrado na ortótese de tornozelo do sistema SmartOs, baseando-se numa visão centralizada no utilizador. O BS desenvolvido fornece estimulação sensorial, sonora e visual através de motores vibratórios, auscultadores e um díodo emissor de luz vermelha-verde-azul, respetivamente. O BS inclui um microcontrolador que gere a ativação dos estímulos de acordo com o torque de interação e trajetória de referência da ortótese do tornozelo. Os estímulos sensorial e sonoro foram escolhidos para ensinar o utilizador sobre: quando e como executar o contacto entre o pé, parético e não parético, e o solo; o sentido de rotação do tornozelo ao longo do ciclo da marcha; e a força muscular necessária ao longo do ciclo da marcha. O estímulo visual é usado para ajudar o terapeuta a seguir o desempenho dos pacientes ao longo da terapia, de forma que o terapeuta possa ajudá-los e motivá-los.
A partir da validação com sujeitos saudáveis, verificou-se que o BS aumentou significativamente o desempenho motor do utilizador durante a marcha com a ortótese. O sistema mostrou-se capaz de ensinar os utilizadores sobre a direção e magnitude da força muscular necessária ao longo do ciclo da marcha, melhorando a interação entre o humano e a ortótese. O trabalho futuro envolve a melhoria das estratégias que visam o contacto entre o pé e o solo e a validação do sistema com mais participantes e treinos mais longos
Dispositivos móveis de saúde: viabilidade económica e social dos Wearables como complemento aos sistemas de informação na saúde
Estudo da viabilidade comercial, bem como do benefício dos dados e funcionalidades dos dispositivos móveis e wearables como complemento às ferramentas e sistemas de informação atuais na prestação dos cuidados de saúde. Com o propósito de disseminar o acesso às tecnologias que promovem o bem-estar e a saúde pública, aperfeiçoar as potencialidades que a introdução destas tecnologias podem trazer ao atual ambiente tecnológico das instituições de saúde, estas tecnologias wearables podem revelar enriquecimento da informação dos processos clínicos dos doentes, e na monitorização de indicadores e comportamentos de pessoas ou grupos de risco. Com o uso de técnicas de business intelligence e dos conceitos que a internet das coisas (IoT - internet of things) podem ser melhorados processo e retirados indicadores importantes para a consolidação de conhecimento, enriquecendo assim os processos de doentes e atuação dos profissionais. São tidos em conta os trâmites legais que regem este tipo de tecnologias e o regime geral de proteção de dados que será particularmente relevante nestas implementações, uma vez que as questões legais são incontornáveis na implementação de qualquer tipo de negócio, sendo ainda mais estritas em áreas sensíveis como a saúde
Wearable biofeedback improves human-robot compliance during ankle-foot exoskeleton-assisted gait training: a pre-post controlled study in healthy participants
Supplementary material available at: https://www.mdpi.com/1424-8220/20/20/5876/s1The adjunctive use of biofeedback systems with exoskeletons may accelerate post-stroke gait rehabilitation. Wearable patient-oriented human-robot interaction-based biofeedback is proposed to improve patient-exoskeleton compliance regarding the interaction torque’s direction (joint motion strategy) and magnitude (user participation strategy) through auditory and vibrotactile cues during assisted gait training, respectively. Parallel physiotherapist-oriented strategies are also proposed such that physiotherapists can follow in real-time a patient’s motor performance towards effective involvement during training. A preliminary pre-post controlled study was conducted with eight healthy participants to conclude about the biofeedback’s efficacy during gait training driven by an ankle-foot exoskeleton and guided by a technical person. For the study group, performance related to the interaction torque’s direction increased during (p-value = 0.07) and after (p-value = 0.07) joint motion training. Further, the performance regarding the interaction torque’s magnitude significantly increased during (p-value = 0.03) and after (p-value = 68.59 × 10−3) user participation training. The experimental group and a technical person reported promising usability of the biofeedback and highlighted the importance of the timely cues from physiotherapist-oriented strategies. Less significant improvements in patient–exoskeleton compliance were observed in the control group. The overall findings suggest that the proposed biofeedback was able to improve the participant-exoskeleton compliance by enhancing human-robot interaction; thus, it may be a powerful tool to accelerate post-stroke ankle-foot deformity recovery.INCT-EN -Instituto Nacional de Ciência e Tecnologia para Excitotoxicidade e Neuroproteção(UIDB/04436/2020
Virtual reality tools for post-stroke balance rehabilitation: a review and a solution proposal
Stroke is the leading cause of long-term disability in adults, giving rise to balance loss. Virtual reality (VR)-based tools can complement conventional therapy, accelerating post-stroke balance recovery by evolving the patients in an immersive and enthusiastic environment for balance training. This work aims to review the specifications of VR-based tools regarding the VR technology, embedded sensors, motor tasks, virtual challenges, and control strategies for post-stroke balance rehabilitation and to present a solution proposal to tackle current issues on this topic. This review selected 21 articles from the Scopus database. The results show that screens are the most used VR technology, combined or not with auditory and vibrotactile feedback. Cameras and balance boards/platforms are integrated into VR for real-time feedback of the patients' motion. Treadmill walking, weight shifting/bearing, pelvic/hip movements are the most common motor tasks for balance training. Future research may explore the use of wearable sensors and the user-centered design of closed-loop control strategies and virtual challenges for personalized balance training.This work has been supported by the FEDER Funds through the COMPETE 2020-Programa Operacional Competitividade e Internacionalizacao (POCI) and P2020 with the Reference Project SmartOs Grant POCI-01-0247-FEDER-039868, and by FCT national funds, under the national support to R&D units grant, through the reference project UIDB/04436/2020 and UIDP/04436/2020, and under scholarship reference 2020.05709.BD
Robotic biofeedback for post-stroke gait rehabilitation: a scoping review
This review aims to recommend directions for future research on robotic biofeedback towards prompt post-stroke gait rehabilitation by investigating the technical and clinical specifications of biofeedback systems (BSs), including the complementary use with assistive devices and/or physiotherapist-oriented cues. A literature search was conducted from January 2019 to September 2022 on Cochrane, Embase, PubMed, PEDro, Scopus, and Web of Science databases. Data regarding technical (sensors, biofeedback parameters, actuators, control strategies, assistive devices, physiotherapist-oriented cues) and clinical (participants’ characteristics, protocols, outcome measures, BSs’ effects) specifications of BSs were extracted from the relevant studies. A total of 31 studies were reviewed, which included 660 stroke survivors. Most studies reported visual biofeedback driven according to the comparison between real-time kinetic or spatiotemporal data from wearable sensors and a threshold. Most studies achieved statistically significant improvements on sensor-based and clinical outcomes between at least two evaluation time points. Future research should study the effectiveness of using multiple wearable sensors and actuators to provide personalized biofeedback to users with multiple sensorimotor deficits. There is space to explore BSs complementing different assistive devices and physiotherapist-oriented cues according to their needs. There is a lack of randomized-controlled studies to explore post-stroke stage, mental and sensory effects of BSs.This work has been supported in part by the FEDER Funds through the COMPETE 2020—Programa Operacional Competitividade e Internacionalização (POCI) and P2020 with the Reference Project SmartOs Grant POCI-01-0247-FEDER-039868, and by FCT national funds, under the national support to R&D units grant, through the reference project UIDB/04436/2020 and UIDP/04436/2020, under scholarship reference 2020.05709.BD, and under Stimulus of Scientific Employment with the grant 2020.03393.CEECIND
A pessoa com doença pulmonar obstrutiva crónica e suporte de ventilação não invasiva: adesão ao regime terapêutico
Dissertação de Mestrado em Enfermagem de Reabilitação apresentada na Escola Superior de Saúde do Instituto Politécnico de Viana do CasteloA Doença Pulmonar Obstrutiva Crónica (DPOC) carateriza-se por uma obstrução brônquica persistente e geralmente progressiva, associada a uma resposta inflamatória crónica do pulmão e das vias aéreas, muitas vezes secundária a um agente externo. É a doença respiratória crónica mais comum a nível mundial, e estima-se que em Portugal cerca de 14% da população acima dos 40 anos tenham DPOC. Atualmente a VNI surge como um procedimento standard no tratamento de pessoas com reagudizações da DPOC, observando-se uma evidente melhoria clínica nas situações de reagudizações, bem como uma diminuição da necessidade de intubação traqueal, complicações, mortalidade, internamento hospital e, ainda, no custo económico da hospitalização.
O objetivo geral do presente estudo consiste em perceber quais os fatores principais que interferem na adesão terapêutica das pessoas com DPOC a efetuar VNI domiciliária, tendo como finalidade desocultar a importância da intervenção do Enfermeiro Especialista em Enfermagem de Reabilitação no cuidar destas pessoas, que se traduzirá em ganhos em saúde e maximização da sua qualidade de vida. Para tal, foi efetuado um estudo qualitativo de carácter exploratório e descritivo com recurso à entrevista semiestruturada a nove participantes seguidos em consulta de Pneumologia de um Hospital Central da Zona Norte. Adicionalmente, foram recolhidos dados do processo clínico, nomeadamente, a taxa de adesão. A análise dos dados foi efetuada recorrendo à codificação segundo Hernández Sampieri, Fernández Collado e Baptista Lúcio (2013).
Os resultados obtidos permitem concluir que, de uma maneira geral todos participantes apresentam algum tipo constrangimento referente à utilização da VNI, nomeadamente, congestão nasal, secura das mucosas, úlcera de pressão no nariz, distensão gástrica, conjuntivite, entre outras. Relativamente à adesão à utilização de VNI, todos os participantes afirmaram que cumpriam, contrastando com dados médicos cuja média rondava os 88%. De notar que nenhum participante se encontrava a realizar qualquer tipo de programa de reabilitação respiratória. Verificou-se que a maioria dos participantes apresentam dificuldades e constrangimentos relacionados com a utilização da VNI, condicionando a sua total adesão ao tratamento estabelecido, levando a perdas em saúde e qualidade de vida. Estes resultados sugerem a necessidade de intervenção de enfermagem de reabilitação nas pessoas com DPOC com VNI.Chronic Obstructive Pulmonary Disease (COPD) is characterized by a persistent and generally progressive bronchial obstruction, associated with a chronic inflammatory response of the lung and airways, often secondary to an external agent. It is the most common chronic respiratory disease worldwide, and it is estimated that about 14% of the Portuguese population over 40 years old is affected by the disease. Currently, NIV (Non Invasive Ventilation) emerges as a standard procedure in the treatment of people with COPD re-emergencies showing an evident clinical improvement, as well as a decrease in the need for a tracheal intubation, other complications, mortality, hospitalization and also in the hospitalization economic cost.
The main objective of the present study is to understand which are the main factors that influences the therapeutic adherence of people with COPD that are performing home NIV. The goal is to highlight the important intervention and role of the Nurse Specialist in Rehabilitation Nursing in caring for these people, which will translate into health gains and maximizing their quality of life. Therefore, an exploratory and descriptive type of qualitative study was carried out through a semi-structured interview with nine participants that are being followed in a Pulmonology consultation at a Central Hospital in the North of Portugal. In this study, data such as the adherence rate was gathered to later cross-check with the data collected in the interviews. The data analysis was performed using coding according to Hernández Sampieri, Fernández Collado and Baptista Lúcio (2013).
The obtained results indicate that, in general, all participants show some kind of constraints regarding the use of NIV, namely nasal congestion, dryness of mucous membranes, pressure ulcer in the nose, gastric distension, a set, among others. Regarding VNI use adherence, all of the participants mentioned that were complied with the therapeutic plan, contrary to the 88% of adherence obtained from the medical data. It is important to highlight that none of the participants were performing any type of respiratory rehabilitation program. It was observed that most of the participants showed difficulties and constraints related to the use of NIV, which conditions their total adherence to the established treatment, leading to losses in health and quality of life. The obtained results suggest an important need of intervention of rehabilitation nursing for people with COPD
Estudo da variação da espessura de tinta em peças plásticas
Dissertação de mestrado integrado em Engenharia de PolímerosO presente relatório descreve o trabalho desenvolvido na empresa DELPHI AUTOMOTIVE SYSTEMS
PORTUGAL, no âmbito da Dissertação de Mestrado em Engenharia de Polímeros. O trabalho consistiu na
realização de um estágio curricular, em ambiente industrial, com a duração de cerca de seis meses cujos
principais objetivos são: i) estudo da variação de espessura de tinta nas peças plásticas a fim de estabelecer
relação entre a espessura da tinta obtida nos elementos de controlo e nas peças plásticas; ii) estudo da
influência das variáveis operatórias na distribuição de espessura.
Numa primeira fase, começou-se por definir a metodologia seguida no estudo das peças produzidas e
pintadas na empresa com o intuito de estudar a variação da espessura de tinta nas peças ao longo da
produção de um lote de pintura. Numa fase posterior, estudou-se a influência das variáveis operatórias na
variação de espessura de tinta. Para isso, começou-se por verificar quais as variáveis operatórias mais
influentes no processo de pintura a fim de definir as condições de pintura necessárias para estudar a
influência da sua interação na variação de espessura de tinta.
Para realizar o estudo, começou-se por medir a espessura de tinta nas peças plásticas e nos elementos de
controlo com o medidor de espessura existente na empresa. Depois, mediu-se a espessura de tinta nas
peças plásticas com o Microscópio Ótico existente na Universidade do Minho. A técnica de microscopia
utilizada para medição de espessura de tinta foi a Microscopia de Reflexão com Contraste de Interferência
Diferencial (DIC).
Após a realização do estudo da variação de espessura de tinta nas peças plásticas verificou-se que a
espessura de tinta nas peças plásticas medida com o medidor de espessura é mais elevada do que a
espessura de tinta nos elementos de controlo. A espessura de tinta nas peças plásticas apresenta maior
variação e valores mais elevados quando se efetuam as medições com o medidor de espessura do que
quando se utiliza o Microscópio Ótico, o que permite concluir que a variação de espessura de tinta obtida
nos elementos de controlo é muito semelhante à variação de espessura de tinta nas peças plásticas quando
se utiliza o Microscópio Ótico para efetuar as medições de espessura de tinta.
Em relação ao estudo onde se prevê o efeito das variáveis operatórias no processo de pintura verifica-se
que apenas se conseguem obter peças com a espessura de tinta dentro de especificação quando se utiliza
uma correta relação entre a Atomização, o Fan Pressure e o Flow-Rate.
Por fim, definiram-se os trabalhos futuros que poderão ser desenvolvidos no âmbito deste tema.This report describes the work in the company DELPHI AUTOMOTIVE SYSTEMS PORTUGAL, within the
Master's Thesis in Polymer Engineering. The work consisted of a traineeship in industrial environment,
lasting about six months whose main objectives are: i) study of the variation of thickness of paint on plastic
parts in order to establish the relationship between the thickness of the obtained ink the control elements
and the plastic parts; ii) study of the influence of operational variables in the distribution of ink thickness.
Initially, it was first set the methodology followed in the study of the parts produced and painted in the
company in order to study the variation of the thickness of paint on parts throughout the production of a lot
of painting. At a later stage, he studied the influence of operational variables in variation of ink thickness.
For this, it was first check what the most influential operative variables in the painting process in order to
define the necessary painting conditions to study the influence of their interaction on the variation of ink
thickness.
For the study, it was started by measuring the thickness ink on plastic parts and control elements with the
existing thickness gauge in the company. Then he measured the ink thickness on plastic parts with
Microscope Optical existing at the University of Minho. The microscopy technique for measuring ink
thickness was Reflection Microscopy Differential Interference Contrast (DIC).
After the study of the variation in ink thickness on plastic parts it was found that the ink thickness on plastic
parts measured with the thickness gauge is higher than the ink thickness in which indicates that the variation
in ink thickness obtained in the control elements is very similar to the variation in ink thickness on plastic
parts when using the Optical Microscope to perform the t measurements of ink thickness.
Regarding the study which provides the effect of operational variables in the painting process verifies that
only able to obtain parts with the ink thickness within specification when using a correct relationship between
the atomization, the Fan Pressure and Flow- Rate.
Finally, we defined the future work that may be developed under this theme
Design and usability assessment of multimodal augmented reality system for gait training
Biofeedback is a promising tool to complement conventional physi-cal therapy by fostering active participation of neurologically impaired patients during treatment. This work aims at a user-centered design and usability as-sessment for different age groups of a novel wearable augmented reality (AR) application composed of a multimodal sensor network and corresponding con-trol strategies for personalized biofeedback during gait training. The proposed solution includes wearable AR glasses that deliver visual cues controlled in re-al-time according to mediolateral center of mass position, sagittal ankle angle, or tibialis anterior muscle activity from inertial and EMG sensors. Control strat-egies include positive and negative reinforcement conditions and are based on the user’s performance by comparing real-time sensor data with an automatical user-personalized threshold. The proposed solution allows ambulatory practice on daily scenarios, physiotherapists' involvement through a laptop screen, and contributes to further benchmark biofeedback regarding the type of sensor. Alt-hough old healthy adults with low academic degrees have a preference for guidance from an expert person, excellent usability scores (SUS scores: 81.25-96.87) were achieved with young and middle-aged healthy adults and one neu-rologically impaired patient.This work was funded by the Fundação para a Ciência e Tecnologia under the scholarship reference 2020.05709.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
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