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- Fully automatic segmentation of femurs with medullary canal definition in high and in low resolution CT scansPublication . Almeida, Diogo F.; Ruben, Rui; Folgado, João; Fernandes, Paulo R.; Audenaert, Emmanuel; Verhegghe, Benedict; De Beule, MatthieuFemur segmentation can be an important tool in orthopedic surgical planning. However, in order to over- come the need of an experienced user with extensive knowledge on the techniques, segmentation should be fully automatic. In this paper a new fully automatic femur segmentation method for CT images is pre- sented. This method is also able to define automatically the medullary canal and performs well even in low resolution CT scans. Fully automatic femoral segmentation was performed adapting a template mesh of the femoral vol- ume to medical images. In order to achieve this, an adaptation of the active shape model (ASM) tech- nique based on the statistical shape model (SSM) and local appearance model (LAM) of the femur with a novel initialization method was used, to drive the template mesh deformation in order to fit the in-image femoral shape in a time effective approach. With the proposed method a 98% convergence rate was achieved. For high resolution CT images group the average error is less than 1 mm. For the low resolution image group the results are also accurate and the average error is less than 1.5 mm. The proposed segmentation pipeline is accurate, robust and completely user free. The method is ro- bust to patient orientation, image artifacts and poorly defined edges. The results excelled even in CT images with a significant slice thickness, i.e., above 5 mm. Medullary canal segmentation increases the geometric information that can be used in orthopedic surgical planning or in finite element analysis.
- Digital media as a driver of a more inclusive higher educationPublication . Almeida, Ana Margarida; Santos, Rita; Batista, João; Pereira, Dora; Sousa, Célia MariaDigital media may have a fundamental role in promoting more inclusive social and learning experiences, particularly when considering the challenge of widening participation that Higher Education Institutions (HEI) are currently facing. This article briefly overviews recent policies, initiatives and recommendations that address the use of digital media in promoting a more inclusive higher education (HE) system; the review focuses especially on actions involving HE students and that promote innovative uses of digital media solutions that provide flexible delivery models and alternative ways of communicating, helping students from a variety of non-traditional backgrounds and contexts to actively participate and engage with HE in a more open and inclusive approach. The article also presents preliminary results of an exploratory survey on how Portuguese public HEI websites present the challenge of inclusion, namely through digital media. The results of the review show the increasing importance for HE of ensuring open and inclusive student experiences through the use of digital media, although it seems that there is a lack of policies and information widely available about how this can be achieved, especially for publics other than the learners with disabilities or special education needs. Also, the analysis of the HEI websites does not seem to reveal a great concern in presenting HEI as open, flexible and inclusive for all learners, particularly using digital media. Drawing on the revision undertaken and on the collected data, the authors make recommendations for future research and propose an action plan towards the development of a future research project.
- Choosing sheep (Ovis aries) as animal model for temporomandibular joint research: Morphological, histological and biomechanical characterization of the joint discPublication . Angelo, D.F.; Morouço, P.; Alves, N.; Viana, T.; Santos, F.; González, R.; Monje, F.; Macias, D.; Carrapiço, B.; Sousa, R.; Cavaco-Gonçalves, S.; Salvado, F.; Peleteiro, C.; Pinho, M.Preclinical trials are essential to the development of scientific technologies. Remarkable molecular and cellular research has been done using small animal models. However, significant differences exist regarding the articular behavior between these models and humans. Thus, large animal models may be more appropriate to perform trials involving the temporomandibular joint (TMJ). The aim of this work was to make a morphological (anatomic dissection and white light 3D scanning system), histological (TMJ in bloc was removed for histologic analysis) and biomechanical characterization (tension and compression tests) of sheep TMJcomparing the obtained results with human data. Results showed that sheep processus condy-laris and fossa mandibularis are anatomically similar to the same human structures. TMJ dischas an elliptical perimeter, thinner in the center than in periphery. Peripheral area actsas a ring structure supporting the central zone. The disc cells display both fibroblast andchondrocyte-like morphology. Marginal area is formed by loose connective tissue, with somechondrocyte-like cells and collagen fibers in diverse orientations. Discs obtained a tensile mod-ulus of 3.97 ± 0.73 MPa and 9.39 ± 1.67 MPa, for anteroposterior and mediolateral assessment.The TMJ discs presented a compressive modulus (E) of 446.41 ± 5.16 MPa and their maximumstress value ( max) was 18.87 ± 1.33 MPa. Obtained results suggest that these animals should beconsidered as a prime model for TMJ research and procedural training. Further investigationsin the field of oromaxillofacial surgery involving TMJ should consider sheep as a good animalmodel due to its resemblance of the same joint in humans.© 2016 Elsevier Masson SAS. All rights reserved.
- Blind Guide: anytime, anywherePublication . Yánez, Daniel Vera; Marcillo, Diego; Fernandes, Hugo; Barroso, João; Pereira, AntónioEyesight is an important sense that helps humans to avoid dangers and navigate in our world. Blind people usually have enhanced accuracy and sensibility of their other natural senses in order to sense their surroundings. But sometimes this is not enough because the human senses can be affected by external sources of noise or disease. That is why technology has been used to develop many assistive tools. Artifacts like white canes or braille compasses help blind people moving around in the environment. In this article, the use of a system that detects and recognize nearby objects or obstacles is proposed, giving an audible feedback to the user. It is designed as a wireless system in order to be comfortable to be carried by the user. The system helps visual impaired people to move around in indoor or outdoor scenarios. The goals of this blind guide system is to detect obstacles that white canes or dogs cannot, extending its detection range.
- Marketing experiencial: o estudo de 3 hotéis de charme da região centro de PortugalPublication . Marques, Alzira; Dantas, JoséA competitividade das marcas depende, em parte, de as empresas associarem aos produtos e serviços experiências memoráveis, uma vez que os consumidores os compram não só por aquilo que eles fazem mas também por aquilo que eles significam. Os clientes esperam ser influenciados de um modo positivo, emocional e memorável em todos os níveis da sua vivência comercial. É neste contexto que emerge o marketing experiencial, que tem pautado a orientação estratégica do sector da hotelaria, motivo pelo qual o escolhemos para alvo de estudo. Assim, com base no caso de estudo de 3 hotéis de charme na região de Leiria identificámos as práticas de marketing experiencial implementadas e verificámos que estão relacionadas com o nível de satisfação dos clientes e de popularidade dos hotéis, estão também na origem do WOM positivo que desempenha um papel importante na captação de novos clientes.
- Animais nossos Amigos. Dos versos de Afonso Lopes Vieira aos animais de Pedro Anjos TeixeiraPublication . Nobre, Cristina; Cruz, Sara; Carvalho, Vânia; Coelho, MárioFruto de um percurso acidentado e quase centenário, no acervo do Museu de Leiria incluem-se várias peças cuja memória se foi desvanecendo. É a história de algumas dessas peças que pretendemos nesta ocasião reconstituir. Centrámo-nos nas pequenas estátuas de animais, esculpidas em pedra, por Pedro Anjos Teixeira, que se encontram presentemente no Museu e corporizam os animais-personagens da obra Animais Nossos Amigos, de Afonso Lopes Vieira.
- Interfaces alternativas para brinquedos adaptadosPublication . Soares, Marcos; Conniot, Wilson; Gomes, Hugo; Lopes, Nuno VieiraO presente artigo descreve o trabalho desenvolvido durante o ano letivo 2015/2016 no âmbito da unidade curricular de Projeto em Engenharia Eletrotécnica e de Computadores do curso de Licenciatura em EngenhariaEletrotécnica e de Computadores da Escola Superior de Tecnologia e Gestão (ESTG). São apresentadasideias e objetivos, bem como as metodologias de trabalho utilizadas e os protótipos desenvolvidos deforma a tornar a interação de crianças com brinquedos adaptados mais simples e divertida. Em conjuntocom a campanha “Mil Brinquedos Mil Sorrisos” foram definidas algumas estratégias para melhorar esta interaçãoatravés da inovação e melhoramento dos dispositivos já desenvolvidos. Numa primeira abordagem foi efetuada uma pesquisa sobre as interfaces alternativas já existentes para brinquedosadaptados, sobre os requisitos necessários para cada sistema, o funcionamento e consumos energéticosde cada dispositivo e custos associados. Foram criados dois sistemas de interação: um com fios e outro sem fios, sendo este último constituído por dois elementos (interruptor emissor e recetor). Associado a este sistema sem fios, foi também desenvolvida uma aplicação para dispositivos móveis (sistema operativo Android) que permite ativar o brinquedo adaptado a partir de um Smartphone ou Tablet.
- Cartesian genetic programming applied to pitch estimation of piano notesPublication . Inacio, Tiago; Miragaia, Rolando; Reis, Gustavo; Grilo, Carlos; Fernandez, FranciscoPitch Estimation, also known as Fundamental Frequency (F0) estimation, has been a popular research topic for many years, and is still investigated nowadays. This paper presents a novel approach to the problem of Pitch Estimation, using Cartesian Genetic Programming (CGP). We take advantage of evolutionary algorithms, in particular CGP, to evolve mathematical functions that act as classifiers. These classifiers are used to identify piano notes' pitches in an audio signal. For a first approach, the obtained results are very promising: our error rate outperforms two of three state-of-the-art pitch estimators.
- Advances in electrospun skin substitutesPublication . J.R. Dias; Granja, P.L.; Bártolo, P.J.In recent years, nanotechnology has received much attention in regenerative medicine, partly owing to the production of nanoscale structures that mimic the collagen fibrils of the native extracellular matrix. Electrospinning is a widely used technique to produce micro-nanofibers due its versatility, low cost and easy use that has been assuming an increasingly prominent position in the tissue engineering field. Electrospun systems have been especially investigated for wound dressings in skin regeneration given the intrinsic suitability of fibrous structures for that purpose. Several efforts have been made to combine distinct design strategies, synthetic and/or natural materials, fiber orientations and incorporation of substances (e.g. drugs, peptides, growth factors or other biomolecules) to develop an optimized electrospun wound dressing mimicking the native skin. This paper presents a comprehensive review on current and advanced electrospinning strategies for skin regeneration. Recent advances have been mainly focused on the materials used rather than on sophisticated fabrication strategies to generate biomimetic and complex constructs that resemble the mechanical and structural properties of the skin. The technological limitations of conventional strategies, such as random, aligned and core-shell technologies, and their poor mimicking of the native tissue are discussed. Advanced strategies, such as hybrid structures, cell and in situ electrospinning, are highlighted in the way they may contribute to circumvent the limitations of conventional strategies, through the combination of different technologies and approaches. The main research challenges and future trends of electrospinning for skin regeneration are discussed in the light of in vitro but mainly in vivo evidence.
- First aid drone for outdoor sports activitiesPublication . Bravo, Gustavo Cedeno; Parra, Diego Marcillo; Mendes, Luis; Pereira, Antonio Manuel de JesusPracticing sports in the outdoors as a way to reduce stress levels, improve health; and even as an incentive to improve social relations, has encouraged more and more people to leave the sedentary lifestyle to perform activities like walking, jogging, hiking, biking, among others. This trend to practice outdoor sport activities was also driven by new technological gadgets (e.g., smartphone whit special apps, fitness trackers and smartwatches) since they allow tracking all the workout values (e.g., pace, speed, distance, duration), vita parameters and signals (e.g., heart rate, temperature and calories burned) and also the exercise route (e.g., geographic coordinates). During outdoors sports activities, independently if these are amateur or professional, the sportsman can suffer accidents, which can result in body injuries, or an unexpected health problem (e.g., heart attack, heatstroke and dehydration) that can limit its mobility or even its conscious state. When this happens, an emergency service should be activated. This is the more important the more remote is the site of the emergency. A solution envisaged to provide emergency care as soon as possible in cross-country sports competitions, even when the land topography is very rough, is proposed in this paper. The base idea is to use a drone that carries a first aid kit (bandages, alcohol, cotton, gauze, water, and other emergency and survival products) and has real-time audio and video communications capabilities.