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Magnetic resonance (MR) imaging is the most sensitive clinical tool in the diagnosis and monitoring of multiple sclerosis (MS) alterations. Spinal cord evaluation has gained interest in this clinical scenario in recent years, but, unlike the brain, there is a more limited choice of algorithms to assist spinal cord segmentation. Our goal was to investigate and develop an automatic MR cervical cord segmentation method, enabling automated and seamless spinal cord atrophy assessment and setting the stage for the development of an aggregated algorithm for the extraction of lesion-related imaging biomarkers. The algorithm was developed using a real-world MR imaging dataset of 121 MS patients (96 cases used as a training dataset and 25 cases as a validation dataset). Transversal, 3D T1-weighted gradient echo MR images (TE/TR/FA = 1.7-2.7 ms/5.6-8.2 ms/12°) were acquired in a 3 T system (Signa HD, GEHC) as standard of care in our clinical practice. Experienced radiologists supervised the manual labelling, which was considered the ground-truth. The 2D convolutional neural network consisted of a hybrid residual attention-aware segmentation method trained to delineate the cervical spinal cord. The training was conducted using a focal loss function, based on the Tversky index to address label imbalance, and an automatic optimal learning rate finder. Our automated model provided an accurate segmentation, achieving a validation DICE coefficient of 0.904 ± 0.101 compared with the manual delineation. An automatic method for cervical spinal cord segmentation on T1-weighted MR images was successfully implemented. It will have direct implications serving as the first step for accelerating the process for MS staging and follow-up through imaging biomarkers.
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Medula Cervical , Esclerose Múltipla , Humanos , Medula Cervical/diagnóstico por imagem , Medula Cervical/patologia , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Imageamento por Ressonância Magnética/métodos , Medula Espinal/patologia , AtençãoRESUMO
Lamb waves have emerged as a valuable tool to examine long plate-like structures in a faster way compared to conventional bulk wave techniques, which make them attractive in non-destructive testing. However, they present a multimodal and dispersive nature, which hinders signal identification. Oblique incidence is one of the most known methods to generate and receive Lamb waves and it is applied in different experimental arrangements with different types of sensors. In this work, several setups were conducted and compared to determine the optimal ones to launch and detect ultrasonic Lamb waves, especially in non-homogeneous specimens. The chosen arrangements were contact with angle beam transducers, immersion in a water tank, localised water coupling using conical containers and air coupling. Plates of two different materials were used, stainless steel and Portland cement mortar. Theoretical and experimental dispersion curves were compared to verify the existence of Lamb modes and good correspondence was achieved.
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Aiming at the limitations of the existing Limited Feedback Interference Alignment algorithms, this paper proposes a direct codeword selection scheme that maximizes the lower-bound of the user rate and reduces the sum rate loss by integrating the Bit Allocation algorithm. The target signal is decoded using the maximum signal to interference plus noise ratio (MAX-SINR) algorithm. Moreover, low complexity and global searching mechanisms are deployed to select the optimized codewords from the generated sets of codewords that approach the ideal precoder. Simulation results show that the proposed algorithm effectively improves the rate lower-bound of the system user as compared with the existing state-of-the-art algorithms.
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The main aim of smart cities is to achieve the sustainable use of resources. In order to make the correct use of resources, an accurate monitoring and management is needed. In some places, like underground aquifers, access for monitoring can be difficult, therefore the use of sensors can be a good solution. Groundwater is very important as a water resource. Just in the USA, aquifers represent the water source for 50% of the population. However, aquifers are endangered due to the contamination. One of the most important parameters to monitor in groundwater is the salinity, as high salinity levels indicate groundwater salinization. In this paper, we present a specific sensor for monitoring groundwater salinization. The sensor is able to measure the electric conductivity of water, which is directly related to the water salinization. The sensor, which is composed of two copper coils, measures the magnetic field alterations due to the presence of electric charges in the water. Different salinities of the water generate different alterations. Our sensor has undergone several tests in order to obtain a conductivity sensor with enough accuracy. First, several prototypes are tested and are compared with the purpose of choosing the best combination of coils. After the best prototype was selected, it was calibrated using up to 30 different samples. Our conductivity sensor presents an operational range from 0.585 mS/cm to 73.8 mS/cm, which is wide enough to cover the typical range of water salinities. With this work, we have demonstrated that it is feasible to measure water conductivity using solenoid coils and that this is a low cost application for groundwater monitoring.
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BACKGROUND: This study addressed the problem of evaluating the effectiveness of two protocols of physiotherapy for functional recovery after stroke. In particular, the study explored the use of Functional Principal Component Analysis (FPCA), a multivariate data analysis in order to assess and clarify the process of regaining independence after stroke. METHODS: A randomized double-blind controlled trial was performed. Thirteen subjects with residual hemiparesis after a single stroke episode were measured in both in- and outpatient settings at a district hospital. All subjects were able to walk before suffering the stroke and were hemodynamically stable within the first week after stroke. Control and target groups were treated with conventional physiotherapy for stroke, but specific techniques were added for treatment of the target group depending on patients' functional levels.Independence level was assessed with the Barthel Index (BI) throughout 7 evolution stages (hemodynamic stability, beginning of standing, beginning of physical therapy sessions in the physiotherapy ward and monthly assessment for 6 months after stroke). RESULTS: FPCA was applied for data analysis. Statistically significant differences were found in the dynamics of the recovery process between the two physiotherapy protocols. The target group showed a trend of improvement six months after stroke that was not present in the control group. CONCLUSIONS: FPCA is a method which may be used to provide greater insight into the analysis of the rehabilitation process than that provided by conventional parametric methods. So, by using the whole curves as basic data parameters, subtle differences in the rehabilitation process can be found.FPCA represents a future aid for the fine analysis of similar physiotherapy techniques, when applied in subjects with a huge variability of functional recovery, as in the case of post-stroke patients.
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Análise de Componente Principal/métodos , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Modalidades de FisioterapiaRESUMO
Allopregnanolone (ALLO) is a known neurosteroid and a progesterone metabolite synthesized in the ovary, CNS, PNS, adrenals and placenta. Its role in the neuroendocrine control of ovarian physiology has been studied, but its in situ ovarian effects are still largely unknown. The aims of this work were to characterize the effects of intrabursal ALLO administration on different ovarian parameters, and the probable mechanism of action. ALLO administration increased serum progesterone concentration and ovarian 3ß-HSD2 while decreasing 20α-HSD mRNA expression. ALLO increased the number of atretic follicles and the number of positive TUNEL granulosa and theca cells, while decreasing positive PCNA immunostaining. On the other hand, there was an increase in corpora lutea diameter and PCNA immunostaining, whereas the count of TUNEL-positive luteal cells decreased. Ovarian angiogenesis and the immunohistochemical expression of GABAA receptor increased after ALLO treatment. To evaluate if the ovarian GABAA receptor was involved in these effects, we conducted a functional experiment with a specific antagonist, bicuculline. The administration of bicuculline restored the number of atretic follicles and the diameter of corpora lutea to normal values. These results show the actions of ALLO on the ovarian physiology of the female rat during the follicular phase, some of them through the GABAA receptor. Intrabursal ALLO administration alters several processes of the ovarian morpho-physiology of the female rat, related to fertility and oocyte quality.
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Pregnanolona , Progesterona , Gravidez , Feminino , Ratos , Animais , Pregnanolona/farmacologia , Progesterona/farmacologia , Antígeno Nuclear de Célula em Proliferação , Bicuculina/farmacologia , Receptores de GABA-A , Corpo LúteoRESUMO
Rehabilitation is a discipline increasingly growing around the world due to several reasons, but probably the most important one is aging population and chronicity. A need to harmonize education has been identified, and although several International organizations such as the European Union of Medical Specialists (UEMS) and the International Society of Physical Medicine and Rehabilitation (ISPRM) have defined standards, given the quick growth of new evidence and assessment methods an urge to establish new ones arises. Functional assessment and tools used to do so are key in rehabilitation processes. This comprises self-reported questionnaires, conventional clinical evaluation but more notably high technology assessment methods, such as movement analysis systems, posturography, different types of dynamometers and kinesiologic electromyography among others. More recently, a wide range of wearable systems has been introduced in patient assessment. This is generating many published protocols as well as reliability and validity studies. The objective of this narrative review is to present main assessment technologies relevant to rehabilitation, its situation of this specific area in pre-graduate and post-graduate rehabilitation educational programs, and to elaborate a formative proposal including technological foundations of assessment and also highlighting the importance of solid reliability and validity of assessment methods comprehension. The main objective of this proposal is to provide basic knowledge about rehabilitation and methodologies for outcomes evaluation, including new technologies, to all health professionals, but especially to those who work or will work in the field of Rehabilitation.
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This document provides a review of the techniques and therapies used in gait rehabilitation after stroke. It also examines the possible benefits of including assistive robotic devices and brain-computer interfaces in this field, according to a top-down approach, in which rehabilitation is driven by neural plasticity.The methods reviewed comprise classical gait rehabilitation techniques (neurophysiological and motor learning approaches), functional electrical stimulation (FES), robotic devices, and brain-computer interfaces (BCI).From the analysis of these approaches, we can draw the following conclusions. Regarding classical rehabilitation techniques, there is insufficient evidence to state that a particular approach is more effective in promoting gait recovery than other. Combination of different rehabilitation strategies seems to be more effective than over-ground gait training alone. Robotic devices need further research to show their suitability for walking training and their effects on over-ground gait. The use of FES combined with different walking retraining strategies has shown to result in improvements in hemiplegic gait. Reports on non-invasive BCIs for stroke recovery are limited to the rehabilitation of upper limbs; however, some works suggest that there might be a common mechanism which influences upper and lower limb recovery simultaneously, independently of the limb chosen for the rehabilitation therapy. Functional near infrared spectroscopy (fNIRS) enables researchers to detect signals from specific regions of the cortex during performance of motor activities for the development of future BCIs. Future research would make possible to analyze the impact of rehabilitation on brain plasticity, in order to adapt treatment resources to meet the needs of each patient and to optimize the recovery process.
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Marcha/fisiologia , Reabilitação do Acidente Vascular Cerebral , Interpretação Estatística de Dados , Estimulação Elétrica , Eletroencefalografia , Humanos , Aprendizagem , Movimento , Neurofisiologia , Robótica , Espectroscopia de Luz Próxima ao Infravermelho , Interface Usuário-ComputadorRESUMO
The first step to detect when a vineyard has any type of deficiency, pest or disease is to observe its stems, its grapes and/or its leaves. To place a sensor in each leaf of every vineyard is obviously not feasible in terms of cost and deployment. We should thus look for new methods to detect these symptoms precisely and economically. In this paper, we present a wireless sensor network where each sensor node takes images from the field and internally uses image processing techniques to detect any unusual status in the leaves. This symptom could be caused by a deficiency, pest, disease or other harmful agent. When it is detected, the sensor node sends a message to a sink node through the wireless sensor network in order to notify the problem to the farmer. The wireless sensor uses the IEEE 802.11 a/b/g/n standard, which allows connections from large distances in open air. This paper describes the wireless sensor network design, the wireless sensor deployment, how the node processes the images in order to monitor the vineyard, and the sensor network traffic obtained from a test bed performed in a flat vineyard in Spain. Although the system is not able to distinguish between deficiency, pest, disease or other harmful agents, a symptoms image database and a neuronal network could be added in order learn from the experience and provide an accurate problem diagnosis.
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Agricultura/instrumentação , Agricultura/métodos , Processamento de Imagem Assistida por Computador/métodos , Telemetria/métodos , Vitis/fisiologia , Algoritmos , Redes de Comunicação de Computadores/instrumentação , Monitoramento Ambiental/métodos , Desenho de Equipamento , Modelos Teóricos , Redes Neurais de Computação , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador/instrumentação , Telemetria/instrumentação , Tecnologia sem FioRESUMO
INTRODUCTION: The study of plantar pressure distribution allows detecting possible overpressure in areas of the foot that could cause discomfort or even injury. The use of dressings is a possible measure for for proper management of pressure to prevent and treat pressure sores. MATERIALS AND METHODS: An experimental study was designed to calculate the pressure level with and without the use of Allevyn dressing: Allevyn Gentle and Gentle Border in the forefoot, and Allevyn Gentle Border Heel in the Heel of five healthy people. The measurements were performed with bare feet and with different dressings controlling gait speed to achieve uniform cadences. Biofoot/IBV V6.0., a system of instrumented insoles, was used to determine pressure in the forefoot and the heel. RESULTS: Allevyn Gentle Border Heel reduced 45% the average pressure and 42% the maximum pressure (p <0.05). Allevyn Gentle and Allevyn Gentle Border reduced 27% the average pressure and 23%-25% maximum pressures (p <0.05). DISCUSSION: Although our study has some limitations, such as the valuation based on healthy volunteers and walking with bare feet, we can establish that dressings studied, had a local lowering effect of pressure on the foot (heel and forefoot) during the gait cycle.
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Bandagens , Antepé Humano/fisiologia , Calcanhar/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PressãoRESUMO
According to World Health Organization (WHO) estimations, one out of five adults worldwide will be obese by 2025. Worldwide obesity has doubled since 1980. In fact, more than 1.9 billion adults (39%) of 18 years and older were overweight and over 600 million (13%) of these were obese in 2014. 42 million children under the age of five were overweight or obese in 2014. Obesity is a top public health problem due to its associated morbidity and mortality. This paper reviews the main techniques to measure the level of obesity and body fat percentage, and explains the complications that can carry to the individual's quality of life, longevity and the significant cost of healthcare systems. Researchers and developers are adapting the existing technology, as intelligent phones or some wearable gadgets to be used for controlling obesity. They include the promoting of healthy eating culture and adopting the physical activity lifestyle. The paper also shows a comprehensive study of the most used mobile applications and Wireless Body Area Networks focused on controlling the obesity and overweight. Finally, this paper proposes an intelligent architecture that takes into account both, physiological and cognitive aspects to reduce the degree of obesity and overweight.
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Monitorização Fisiológica , Obesidade , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Adolescente , Adulto , Criança , Feminino , Saúde Global , Promoção da Saúde , Humanos , Masculino , Obesidade/etiologia , Obesidade/prevenção & controle , Obesidade/terapia , Adulto JovemRESUMO
Introducción: la Ley 35/2015 valora daños y perjuicios en los accidentes de circulación y trata de garantizar una respuesta igualitaria ante situaciones idénticas. La valoración funcional biomecánica (VFB) es una prueba médica complementaria que aporta objetividad en la evaluación de la cervicalgia postraumática. Este estudio analiza la variabilidad interobservador del sistema de valoración de la Ley 35/2015 y estudia el efecto de la VFB y del perfil del evaluador en la determinación de secuelas.Material y métodospara ello, 49 profesionales de la valoración del daño corporal evaluaron 5 casos clínicos de accidentados con cervicalgia postraumática; un mes más tarde, 35 de los anteriores valoraron los mismos casos incluyendo informe de VFB.Resultadoshay una elevada variabilidad en la determinación de los días de perjuicio personal (coeficientes kappa entre 0,04 y 0,073) con o sin VFB; una elevada variabilidad interobservador en la valoración de las secuelas en los casos sin VFB (coeficientes kappa entre 0,022 y 0,044), que mejora discretamente con VFB (coeficientes kappa entre 0,128 y 0,26), aún mostrando concordancia débil. El resultado de la VFB tiene influencia en la determinación de las secuelas (p < 0,01), no así el perfil del evaluador. Más del 79,4% de los evaluadores encontraron útiles las pruebas para poner de manifiesto o confirmar sintomatología, recuperación o simulación.Conclusionesexiste variabilidad en la aplicación de la Ley 35/2015 para la valoración de los accidentados de tráfico con cervicalgia postraumática entre los profesionales del daño corporal. La VFB resulta de utilidad para los evaluadores y tiene influencia en la determinación de las secuelas. (AU)
Introduction: Law 35/2015 assesses damages in traffic accidents and tries to guarantee an equal response to identical situations. Biomechanical functional assessment (BFA) is a complementary medical test that provides objectivity in the evaluation of post-traumatic neck pain. This study analyzes the interobserver variability of the assessment system defined by Law 35/2015 and studies the effect of having BFA tests and the profile of the evaluator in determining sequelae.Materials and methodsTo do this, 49 professionals in the assessment of bodily injury evaluated 5 clinical cases of accident victims with post-traumatic neck pain; a month later, 35 of them assessed the same cases including a BFA report.ResultsThe results show high variability in determining the days of personal injury (Kappa coefficients between 0.04 and 0.073) with or without BFA; high interobserver variability in the assessment of sequelae in cases without BFA (Kappa coefficients between 0.022 and 0.044), which slightly improves with BFA (Kappa coefficients between 0.128 and 0.26), even showing weak concordance. The BFA has an influence on the determination of sequelae (p < 0.01), but the profile of the evaluator does not. More than 79.4% of the evaluators found the BFA tests useful to reveal or to confirm symptoms, recovery, or simulation.ConclusionsThere is variability in the application of Law 35/2015 for the assessment of traffic accidents among professionals of bodily injury. The BFA is useful for evaluators and influences the determination of sequelae. (AU)
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Humanos , Medicina Legal/métodos , Cervicalgia/terapia , Cervicalgia/diagnóstico , Acidentes de Trânsito , Avaliação de Danos , FotogrametriaRESUMO
We consider in this paper the problem of automatic detection of ultrasonic echo pulses in a grain noise background. We start by assuming a reference model for grain noise: multivariate correlated Gaussian model having, in general, different variances under every hypothesis. We show that, even for this simple model, there is not practical optimum solution, except if the variances are equal under every hypothesis and the echo pulse satisfies a spectral constraint. Then we consider split-spectrum (SS) suboptimum solutions. Firstly, SS algorithms are formulated following an algebraic approach which is appropriate in an automatic detection framework. Popular minimization and polarity thresholding algorithms are considered under this framework. Then a new detector called normalized SS (NSS) is proposed. The underlying idea is to actually exploit the tuning frequency sensitivity (i.e., variability of the output magnitudes from one SS channel to another), making this measurement independent of the absolute magnitudes. Different experiments with simulated and real data show evidences of the interest of the new method in an automatic detection framework. Derivations of the formulas for fitting the probability of false alarm in every detector are included in the paper.
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Introducción: El estudio de la distribución plantar de presiones permite detectar posibles sobrepresiones en zonas de la planta del pie que podrían ocasionar disconfort o incluso lesiones. La utilización de apósitos constituye una medida para el manejo adecuado de aquellas en la prevención y tratamiento de las úlceras por presión. Material y métodos: Se diseñó un estudio experimental para calcular el nivel de presión con y sin los apósitos Allevyn Gentle y Allevyn Gentle Border en el antepié y Allevyn Gentle Border Heel en el talón de cinco personas sanas. Las mediciones se realizaron con el pie descalzo y con los diferentes apósitos controlando la velocidad de marcha para conseguir cadencias de marcha homogénea. Para determinar las presiones en el antepié y el talón se utilizó un sistema de plantillas instrumentadas, Biofoot/IBV V6.0. Resultados: La presencia del Allevyn Gentle Border Heel en el talón produjo una reducción de las presiones del orden del 45% para las medias y del 42% para las máximas (p <0.05). Allevyn Gentle Border y Allevyn Gentle en el antepié consiguieron una reducción de la presión media de un 27% y del 23-25% para la presión máxima (p<0.05). Discusión: Aunque nuestro estudio tiene algunas limitaciones, como la valoración basada en voluntarios sanos y marcha con pie descalzo, podemos establecer que los apósitos estudiados presentaron un efecto reductor local de la presión en el pie (talón o antepié) durante el ciclo de la marcha(AU)
The study of plantar pressure distribution allows detecting possible overpressure in areas of the foot that could cause discomfort or even injury. The use of dressings is a possible measure for for proper management of pressure to prevent and treat pressure sores. Materials and methods: An experimental study was designed to calculate the pressure level with and without the use of Allevyn dressing: Allevyn Gentle and Gentle Border in the forefoot, and Allevyn Gentle Border Heel in the Heel of five healthy people. The measurements were performed with bare feet and with different dressings controlling gait speed to achieve uniform cadences. Biofoot/IBV V6.0., a system of instrumented insoles, was used to determine pressure in the forefoot and the heel. Results: Allevyn Gentle Border Heel reduced 45% the average pressure and 42% the maximum pressure (p <0.05). Allevyn Gentle and Allevyn Gentle Border reduced 27% the average pressure and 23%-25% maximum pressures (p <0.05) Discussion: Although our study has some limitations, such as the valuation based on healthy volunteers and walking with bare feet, we can establish that dressings studied, had a local lowering effect of pressure on the foot (heel and forefoot) during the gait cycle(AU)