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- Off-training levels of physical activity and sedentary behavior in young athletes: preliminary results during a typical weekPublication . Exel, Juliana; Mateus, Nuno; Travassos, Bruno; Gonçalves, Bruno; Gomes, Isabel; Leite, Nuno; Sampaio, JaimeThe level of physical activity (PA) and sedentary behavior (SED) off-training of young athletes may reveal the quality of recovery from training and highlight health related issues. Thus, the aim was to identify and describe young athletes' PA and SED off-training, according to daily life activities. Eight athletes (15.7 ± 2 years, 1.72 ± 0.6 m height, 62.9 ± 10.2 kg) of a sport talent program wore on their waist a tri-axial accelerometer (ActiGraph® wGT9X-link, Shalimar, FL, USA) at 30 Hz for 15 consecutive days, and reported their schedule. A two-step cluster analysis classified three groups according to sedentary PA and MVPA. The Sedentary (56.9%), presented the highest sedentary PA (mean [CI], 37.37 [36.45⁻38.29] min/hour); The Hazardous (19.4%) had the lowest values of sedentary and MVPA (10.07 [9.41⁻10.36] min/hour and 8.67 [7.64⁻9.70] min/hour, respectively). Balanced (23.7%) had the highest MVPA (28.61 [27.16⁻30.07] min/hour). Sedentary had the lowest count of home time associated (20%) and higher school (26%) time when compared to the Hazardous (13%). The Balanced showed the highest count of school (61%) and home time (47%). Different profiles for young athletes revealed alarming behavior in the associations with sedentary PA, sitting and SED breaks, which may influence performance and health.
- DualismoPublication . Rosa, José Maria SilvaO dualismo é uma doutrina que afirma a existência de dois princípios opostos e irredutíveis. A versão mais extrema é a do dualismo ontológico substancial, que encontramos especialmente nos sistemas gnósticos e na doutrina maniqueia dos primeiros séculos da era cristã. Mas pode assumir historicamente várias formas mais circunscritas, com o dualismo antropológico (corpo / alma; homem velho / homem novo; “res extensa” / “res cogitans”, etc.), o dualismo cosmológico (trevas / luz; matéria / espírito), o dualismo gnosiológico, (conhecimento pelos sentidos, “doxa”/ conhecimento pela razão, “episteme”) , dualismo cristológico (o Jesus histórico e o Cristo da fé; a existência de duas pessoas em Cristo, conforme o nestorianismo), etc.
- Conselho e Protocolo Familiar no Planeamento da SucessãoPublication . Matias, Cláudia Sofia Martins; Franco, Mário José BaptistaA relevância e o papel das empresas familiares no tecido empresarial português é inegável, contudo, a mudança geracional, a transferência de liderança ou de propriedade são pontos críticos neste segmento de empresas. Deste modo, o desafio passa por planear, preparar e investir atempadamente no processo de sucessão, de forma sólida e consensual, para que estas empresas se tornem estáveis, sustentáveis e consolidadas e, por conseguinte, sobreviverem. A literatura tem vindo a mostrar que, se este tipo de empresas utilizar alguns instrumentos, órgãos ou grupos que auxiliam esse processo, pode fortalecer a hipótese de sucesso do seu processo de sucessão e a continuidade das mesmas. Neste contexto, o principal objetivo deste estudo foi compreender o papel que o conselho e o protocolo familiares podem ter no processo de planeamento das empresas familiares portuguesas. Assim, para alcançar este objetivo geral foi utilizada a abordagem qualitativa, recorrendo a estudos de caso múltiplos: sete empresas familiares portuguesas. Como técnicas de recolha de dados usou-se a entrevista, a observação direta e a análise documental. Com base nas evidências empíricas conclui-se que o conselho de família e o protocolo familiares ajudam o planeamento da sucessão e favorecem a continuidade e sobrevivência da empresa familiar. Contudo, existem também outros grupos de trabalho que auxiliam todo o processo de planeamento como é o caso da reunião da geração de primos e a Comissão de Acompanhamento das gerações mais novas (ou Comité Mentor). O desenvolvimento de planos pessoais futuros para as gerações mais novas pode passar pela criação desta Comissão, que auxilia e encaminha os membros familiares mais jovens. Este estudo mostra ainda que o conselho de família é um órgão muito importante e fundamental nas empresas familiares, sendo um elemento diferenciador de forma positiva neste tipo de empresas. Deve ser criado envolvimento e compromisso familiar com o futuro da empresa através da representação de todos os ramos e gerações da família nas reuniões do conselho de família, mesmo que seja apenas como ouvintes, sem direito de voto. Conclui-se também que o protocolo familiar é considerado um elemento preventivo, com elevado poder sentimental e de muita importância para as empresas familiares, servindo para manter a agregação familiar e a estabilidade na organização, ligando a família à empresa e vice-versa. Este instrumento antecipa também soluções para eventuais problemas ou conflitos futuros, incorporando todas as instruções, regras e preceitos familiares que regem o funcionamento e o relacionamento da família com a empresa, pré-discutidas e aceites por todos. Relativamente ao planeamento da sucessão, este estudo mostra que o início do envolvimento dos membros familiares na empresa parece ditar o início do processo de sucessão. Este envolvimento pode ser auxiliado com a Comissão de Acompanhamento. A escolha do sucessor ocorre em conselho de família, opinada por vezes também pelo conselho de administração. A preparação adequada e devidamente planeada para o processo de sucessão apresentam maior hipótese de sobrevivência e continuidade destas empresas de cariz familiar. Assim, o conselho de família e o protocolo familiar são considerados como ferramentas/instrumentos que auxiliam o planeamento da sucessão neste tipo de empresas familiares. Contudo, a assessoria de profissionais especializados também pode ser vista como mais uma ferramenta e o Comité Mentor das gerações mais novas também se pode envolver no processo de planeamento. De facto, conclui-se que o planeamento tem um claro papel no processo de sucessão das empresas familiares estudadas. Do ponto de vista teórico, este estudo contribui para melhorar o conhecimento sobre o conselho e o protocolo familiares e o planeamento da sucessão nas empresas familiares, na medida em que explorou, em profundidade, estes tópicos. Neste sentido, um dos principais contributos deste trabalho foi propor um modelo holístico que mostra como o conselho e o protocolo familiares podem ser instrumentos que permitem o planeamento da sucessão. Em termos práticos, os resultados deste estudo sugerem que a utilização do conselho de família e do protocolo familiar podem auxiliar o processo de planeamento da sucessão, permitindo a continuidade e sucesso das empresas familiares e minimizando o seu fracasso. A interferência das reuniões da geração de primos e da Comissão de Acompanhamento das gerações mais novas (ou Comité mentor) podem ser também cruciais neste processo de planeamento. Estas e outras contribuições, bem como sugestões para futuras investigações nesta área são também apresentadas.
- Machiavelli's Treatment of Congiure and the Modern OathPublication . Bento, AntónioThe constitution and formulation of «conspiracy» as a first order problem in political philosophy is exclusively due to Machiavelli. It was him who for the first time brought this new subject into political order. With great political virtuosity, for the first time Machiavelli treats conspiracies in a fundamentally pragmatic and technical manner.
- A utilização de drones como ferramenta tecnológica emergente para a inspeção técnica da envolvente de edifíciosPublication . Falorca, Jorge; Lanzinha, JoãoEntre as técnicas de inspeção de edifícios, a inspeção visual é das mais utilizadas, desempenhando um papel relevante na avaliação célere dos problemas construtivos e na definição de um modo adequado de intervenção. No caso da envolvente, este procedimento é também um requisito primordial para garantia da respetiva integridade e segurança. Contudo, o recurso a esta prática simples, pode frequentemente encontrar dificuldades, sobretudo quando os locais a inspecionar são de difícil acesso ou existem riscos de segurança para o inspetor. Torna-se por isso importante encontrar soluções auxiliadoras, que permitam contornar e superar tais contrariedades e das quais possam ainda resultar benefícios substanciais. É neste contexto que surge o recurso à utilização de drones. Estes aparelhos voadores não tripulados, são um instrumento tecnológico que está em franco desenvolvimento. Quando possuidores de determinadas características físicas (geralmente de tamanho pequeno e multirotores) e terem a capacidade de transportar os equipamentos adequados (sobretudo camaras de alta definição “HD” ou térmicas), os drones têm associadas enormes potencialidades para a coadjuvação eficaz, económica e com menores riscos, da monitorização da condição de diversos casos de construções civis, nas quais se inserem, com particular interesse, os edifícios e os elementos construtivos das envolventes exteriores. Tendo em consideração a importância que estas aeronaves estão a assumir como tecnologia robótica emergente na indústria da construção (IC) e o facto de se constituírem como uma ferramenta de elevado potencial para o apoio a atividades de engenharia civil, julgou-se pertinente realizar uma revisão bibliográfica sobre este tema e, nesse seguimento, apresentar as linhas gerais de um trabalho académico simples em que se realizou um ensaio de campo à inspeção das fachadas de um edifício alto. Desta forma, balizam-se alguns aspetos sobre os progressos entretanto alcançados com os drones, tendo sido possível corroborar a grande utilidade e a importância que os mesmos começam a assumir no âmbito da inspeção técnica de edifícios.
- A desmaterialização e o efeito do intangível sobre a sustentabilidade do consumo global de materiaisPublication . Vaz, António Manuel Martins; Devezas, Tessaleno Campos; Silva, Abílio Manuel Pereira daA presente investigação pretende esclarecer se a interação multidisciplinar estabelecida entre as atividades económica, industrial e o consumo global de recursos naturais são compatíveis com um desenvolvimento sustentável. Em primeira instância procedeu-se a uma metodologia quantitativa da evolução do metabolismo global, examinando o consumo de um conjunto de materiais com aplicações essencialmente industriais entre os anos de 1960 e 2015, com a finalidade de identificar alguma tendência de desmaterialização/decoupling. Os resultados obtidos não permitem afirmar perentoriamente que a sociedade está sob o efeito da “desmaterialização” mas entretanto, ressaltaram algumas tendências que admitem algum grau de otimismo. Para uma melhor compreensão do tema desenvolveu-se uma abordagem para quantificar o esforço exigido pelos materiais ao longo do tempo para satisfazer uma determinada necessidade (IEME – Individual Effort Material Economy), examinando empiricamente a evolução das tendências quer do consumo dos materiais assim como dos seus custos associados, a nível global e per capita face ao Produto Interno Bruto (PIB). Posteriormente, procurou identificar-se qual o impacto dos materiais no meio ambiente através de uma metodologia comparativa pela sua toxicidade, situação geoestratégica, risco de oferta, entre outros. Salienta-se que alguns materiais são de extrema relevância podendo funcionar como um elemento impulsionador ou retardatário para o desenvolvimento tecnológico. No quarto capítulo realizou-se um levantamento das empresas a nível mundial com maior valor de mercado. Estas surgiram nas últimas décadas e difundiram-se de uma forma transversal por toda a sociedade dando corpo a empresas TIC com uma crescente componente intangível que aparentemente transportam o seu ADN para outras áreas de atividade. A digitalização surge como fio condutor de uma linguagem universal e globalizada por toda a cadeia de valor. Neste clima versátil e interativo, o valor reside com maior incidência na interoperabilidade entre os produtos e os serviços, o material e o digital. Neste contexto a indústria reconfigura-se numa nova tecnoesfera alicerçada em ambientes ciber físicos, denominada como a quarta revolução industrial (Indústria 4.0). A mudança tecnológica tende a transformar as fábricas digitais em espaços “inteligentes”, descentralizados e otimizados face à transição de uma produção massificada para uma customizada e personalizada, com os respetivos benefícios inerentes. Os novos ambientes proporcionam inovações cada vez mais interativas, complexas e conectadas em que produtos e serviços online se fundem em inovações híbridas e partilhadas, permitindo estabelecer novas relações nos produtos como se de um contribuinte se tratasse, criando inclusivamente uma nova identidade.
- Multi-sensor data fusion in mobile devices for the identification of Activities of Daily LivingPublication . Pires, Ivan Miguel Serrano; Santos, Nuno Manuel Garcia dos; Flórez-Revuelta, FranciscoFollowing the recent advances in technology and the growing use of mobile devices such as smartphones, several solutions may be developed to improve the quality of life of users in the context of Ambient Assisted Living (AAL). Mobile devices have different available sensors, e.g., accelerometer, gyroscope, magnetometer, microphone and Global Positioning System (GPS) receiver, which allow the acquisition of physical and physiological parameters for the recognition of different Activities of Daily Living (ADL) and the environments in which they are performed. The definition of ADL includes a well-known set of tasks, which include basic selfcare tasks, based on the types of skills that people usually learn in early childhood, including feeding, bathing, dressing, grooming, walking, running, jumping, climbing stairs, sleeping, watching TV, working, listening to music, cooking, eating and others. On the context of AAL, some individuals (henceforth called user or users) need particular assistance, either because the user has some sort of impairment, or because the user is old, or simply because users need/want to monitor their lifestyle. The research and development of systems that provide a particular assistance to people is increasing in many areas of application. In particular, in the future, the recognition of ADL will be an important element for the development of a personal digital life coach, providing assistance to different types of users. To support the recognition of ADL, the surrounding environments should be also recognized to increase the reliability of these systems. The main focus of this Thesis is the research on methods for the fusion and classification of the data acquired by the sensors available in off-the-shelf mobile devices in order to recognize ADL in almost real-time, taking into account the large diversity of the capabilities and characteristics of the mobile devices available in the market. In order to achieve this objective, this Thesis started with the review of the existing methods and technologies to define the architecture and modules of the method for the identification of ADL. With this review and based on the knowledge acquired about the sensors available in off-the-shelf mobile devices, a set of tasks that may be reliably identified was defined as a basis for the remaining research and development to be carried out in this Thesis. This review also identified the main stages for the development of a new method for the identification of the ADL using the sensors available in off-the-shelf mobile devices; these stages are data acquisition, data processing, data cleaning, data imputation, feature extraction, data fusion and artificial intelligence. One of the challenges is related to the different types of data acquired from the different sensors, but other challenges were found, including the presence of environmental noise, the positioning of the mobile device during the daily activities, the limited capabilities of the mobile devices and others. Based on the acquired data, the processing was performed, implementing data cleaning and feature extraction methods, in order to define a new framework for the recognition of ADL. The data imputation methods were not applied, because at this stage of the research their implementation does not have influence in the results of the identification of the ADL and environments, as the features are extracted from a set of data acquired during a defined time interval and there are no missing values during this stage. The joint selection of the set of usable sensors and the identifiable set of tasks will then allow the development of a framework that, considering multi-sensor data fusion technologies and context awareness, in coordination with other information available from the user context, such as his/her agenda and the time of the day, will allow to establish a profile of the tasks that the user performs in a regular activity day. The classification method and the algorithm for the fusion of the features for the recognition of ADL and its environments needs to be deployed in a machine with some computational power, while the mobile device that will use the created framework, can perform the identification of the ADL using a much less computational power. Based on the results reported in the literature, the method chosen for the recognition of the ADL is composed by three variants of Artificial Neural Networks (ANN), including simple Multilayer Perceptron (MLP) networks, Feedforward Neural Networks (FNN) with Backpropagation, and Deep Neural Networks (DNN). Data acquisition can be performed with standard methods. After the acquisition, the data must be processed at the data processing stage, which includes data cleaning and feature extraction methods. The data cleaning method used for motion and magnetic sensors is the low pass filter, in order to reduce the noise acquired; but for the acoustic data, the Fast Fourier Transform (FFT) was applied to extract the different frequencies. When the data is clean, several features are then extracted based on the types of sensors used, including the mean, standard deviation, variance, maximum value, minimum value and median of raw data acquired from the motion and magnetic sensors; the mean, standard deviation, variance and median of the maximum peaks calculated with the raw data acquired from the motion and magnetic sensors; the five greatest distances between the maximum peaks calculated with the raw data acquired from the motion and magnetic sensors; the mean, standard deviation, variance, median and 26 Mel- Frequency Cepstral Coefficients (MFCC) of the frequencies obtained with FFT based on the raw data acquired from the microphone data; and the distance travelled calculated with the data acquired from the GPS receiver. After the extraction of the features, these will be grouped in different datasets for the application of the ANN methods and to discover the method and dataset that reports better results. The classification stage was incrementally developed, starting with the identification of the most common ADL (i.e., walking, running, going upstairs, going downstairs and standing activities) with motion and magnetic sensors. Next, the environments were identified with acoustic data, i.e., bedroom, bar, classroom, gym, kitchen, living room, hall, street and library. After the environments are recognized, and based on the different sets of sensors commonly available in the mobile devices, the data acquired from the motion and magnetic sensors were combined with the recognized environment in order to differentiate some activities without motion, i.e., sleeping and watching TV. The number of recognized activities in this stage was increased with the use of the distance travelled, extracted from the GPS receiver data, allowing also to recognize the driving activity. After the implementation of the three classification methods with different numbers of iterations, datasets and remaining configurations in a machine with high processing capabilities, the reported results proved that the best method for the recognition of the most common ADL and activities without motion is the DNN method, but the best method for the recognition of environments is the FNN method with Backpropagation. Depending on the number of sensors used, this implementation reports a mean accuracy between 85.89% and 89.51% for the recognition of the most common ADL, equals to 86.50% for the recognition of environments, and equals to 100% for the recognition of activities without motion, reporting an overall accuracy between 85.89% and 92.00%. The last stage of this research work was the implementation of the structured framework for the mobile devices, verifying that the FNN method requires a high processing power for the recognition of environments and the results reported with the mobile application are lower than the results reported with the machine with high processing capabilities used. Thus, the DNN method was also implemented for the recognition of the environments with the mobile devices. Finally, the results reported with the mobile devices show an accuracy between 86.39% and 89.15% for the recognition of the most common ADL, equal to 45.68% for the recognition of environments, and equal to 100% for the recognition of activities without motion, reporting an overall accuracy between 58.02% and 89.15%. Compared with the literature, the results returned by the implemented framework show only a residual improvement. However, the results reported in this research work comprehend the identification of more ADL than the ones described in other studies. The improvement in the recognition of ADL based on the mean of the accuracies is equal to 2.93%, but the maximum number of ADL and environments previously recognized was 13, while the number of ADL and environments recognized with the framework resulting from this research is 16. In conclusion, the framework developed has a mean improvement of 2.93% in the accuracy of the recognition for a larger number of ADL and environments than previously reported. In the future, the achievements reported by this PhD research may be considered as a start point of the development of a personal digital life coach, but the number of ADL and environments recognized by the framework should be increased and the experiments should be performed with different types of devices (i.e., smartphones and smartwatches), and the data imputation and other machine learning methods should be explored in order to attempt to increase the reliability of the framework for the recognition of ADL and its environments.
- Affinity purification and delivery of a p53-encoding plasmid DNA for gene mediated cancer therapyPublication . Valente, Joana Filipa Abreu Pereira; Sousa, Fani Pereira deCancer is still one of the leading causes of death worldwide. In order to treat this scourge, gene therapy and DNA vaccination have been proposed as an alternative to the common treatments. Among the several gene abnormalities that could be responsible for the oncogenic process, the ones presented in p53 stands up. p53 is one of the most important tumour suppressor gene being considered the “genome guardian” since when occurs exposure to stressful stimuli it is activated through post-transcriptional modifications increasing its stability and activity. This gene is directly and indirectly implicated in different cellular functions, including DNA damage repair, cell cycle arrest in G1/S and apoptosis. Several studies shown that transfection of cancer cells with wild-type p53-expressing plasmids could directly drive cells into apoptosis and/or growth arrest, suggesting that a gene therapy approach for cancer treatment can be related to the re-establishment of the normal p53 function. Recently, the supercoiled (sc) conformation of a p53-encoding plasmid proved to be more efficient in cell transfection and protein expression than open circular conformation. Aiming to successfully isolate this bioactive isoform, several chromatographic techniques have been used, namely amino acids-based affinity chromatography. Concerning this chromatographic approach, in this doctoral work different amino acids like, Lmethionine, L-tyrosine, and arginine, were used to isolate the sc p53 encoding plasmid. From this work, it was achieved a better recovery yield and purity levels for O-Phospho-L-tyrosine when compared with L-methionine agarose matrix. Regarding the macroporous arginine resin, it was possible to recover the sc p53 encoding pDNA with high purity, and an increase of more than 50% in the dynamic binding capacity was achieved, when comparing with their homologous commercial agarose matrix. To understand the activity and the therapeutic effect induced by this sc isoform, different cell lines (HeLa, A549 and human dermal fibroblasts) were transfected with the pDNA purified either by the affinity purification strategy or with a commercial kit, for further in vitro evaluation. In particular, the cytotoxicity, the expression of the p53 transgene and the resulting apoptotic effect were evaluated in these in vitro cancer models. The results brought relevant information concerning the potential application of a sc p53 encoding plasmid in cancer gene therapy. To eliminate different cancer types, treatments must be applied systematically and therefore, must be targeted to cancer cells. Concerning this and, to enable an easy and safe systemic therapy, stable and non-viral gene vectors have been developed to encapsulate and deliver foreign genetic materials in specific cell types, such as cancerous cells. The use of non-viral vectors usually promotes low immune response, they are easily prepared, have a low production cost and also, they can be easily produced at large scale. Other important characteristic about these vectors is the ability to transfer different and large transgenes being also able to be stored for long periods due to their stability. Regarding this, in this doctoral work, chitosan (CH) and polyethyleneimine (PEI) were complexed with different plasmids in order to search for the suitable non-viral nanocomplex combination to be applied for gene therapy. Through the obtained results it was found that p53-encoding pDNA/PEI polyplexes demonstrate some toxicity in normal cells which could be a handicap for future therapeutic application of this nanocarriers. Also, from the track of the nanocarriers inside the cells, it was achieved a better transfection efficiency for the carriers delivering the smaller pDNA. The ability of the polyplexes to promote P53 protein expression was also evaluated using HeLa cancer cells and an increase of 54.2% and 32% of the P53 levels was achieved when CH and PEI nanocarriers were respectively applied. Overall, the scientific work performed in this thesis hopes to lead the scientific community to give more and more relevance to the use of the supercoiled pDNA isoform for gene therapy involving the reestablishment and restoration of the levels of p53. Moreover, it has been shown that the use of chromatography using specific amino acid ligands is a crucial factor in the final quality of the recovered sc pDNA sample, being this a predominant parameter for the accomplishment of the desired therapeutic results. Finally, the effort in the search and development of suitable non-viral vectors should stand up since it can guarantee the stability and activity of the sc p53 encoding plasmid during the delivery process.
- Trajectory control and modelling for wind turbine maintenance by using a RPASPublication . Antunes, Paulo; Bousson, K.; García-Manrique, Juan AntonioOne of the most demanded assets nowadays is energy. Over many options to generate it, humankind must seek sustainable ways; therefore, renewable energies must be empowered. Moreover, wind provides great benefits, granting uncalculated power at our disposition. Since this task is executed by big structures, their maintenance represents a difficult task for human efforts to achieve, because the height requires much support, effort and time to accomplish.
- The impact of globalization and economic freedom on economic growth: the case of the Latin America and Caribbean countriesPublication . Santiago, Renato; Fuinhas, José Alberto; Marques, António CardosoThis study examines the impacts of globalization and economic freedom on the economic growth of a group of 24 developing countries from the Latin America and Caribbean over a time span ranging from 1995 to 2015. We have constructed two models, one with the globalization’s overall value and another with the political, social and economic dimensions of globalization. Our results point out to the fact that globalization has had a positive impact on the economic growth of these countries in the long-run, as well their economic and social dimensions. Still, the political dimension of globalization did not show any statistically significant effect upon growth. In addition, we have found evidence of a negative impact resulting from economic freedom on the economic growth of these Latin American and Caribbean countries in the long-run. In the short-run, the results have indicated that electric power consumption (in all estimations) and social globalization (in only one estimation) were able to promote the economic growth of these countries. Finally, the negative and significant coefficient of the error correction mechanism in all estimations points out to the presence of cointegration/long-memory relationships between the variables. This study aims to contribute to the enrichment of the globalization- growth and economic freedom-growth literature in the way that it attempts to overcome some of the flaws identified in previous studies. In our analysis we have identified and corrected the presence of outliers, which are quite often neglected, and if not controlled can actually compromise the macro-economic analysis of this region. The results from this study should primarily contribute to guide policymakers in their decisions, thus helping them to draw growth-promoting policies in their respective countries.