The current study explores the digital divide by checking the phenomenon at the individual level.... more The current study explores the digital divide by checking the phenomenon at the individual level. It digs into the individual pattern of adoption and use of a broad set of information and communications technologies (ICTs) by introducing a conceptual model combining the extended unified theory of acceptance and use of technology (UTAUT2) and the five-factor model of personality. Therefore, it provides insights on factors affecting technology adoption and the role of personality on individual usage behavior. Most of the UTAUT2 hypotheses are supported, with performance expectancy being the strongest predictor. Openness is a significant predictor of behavioral intention, whereas for usage behavior the significant personality predictors are openness, extraversion and agreeableness. Moreover, as data was collected in Bulgaria and Portugal, a multigroup analysis revealed significant country differences. The effect of performance expectancy, habit, agreeableness and neuroticism on behavioral intention, as well as the effect of age on usage, are stronger for Bulgaria, whereas the effect of hedonic motivation on behavioral intention and the effect of behavioral intention on usage are stronger for Portugal. KEYWORDS Information and communications technologies (ICTs); digital divide, extended unified theory of acceptance and use of technology (UTAUT2); personality UNDP United Nations Development Program UTAUT Unified theory of acceptance and use of technology UTAUT2 Extended unified theory of acceptance and use of technology
Massive open online courses (MOOCs), contribute significantly to individual empowerment because t... more Massive open online courses (MOOCs), contribute significantly to individual empowerment because they can help people learn about a wide range of topics. To realize the full potential of MOOCs, we need to understand their factors of success, here defined as the use, user satisfaction, along the individual and organizational performance resulting from the user involvement. We propose a theoretical framework to identify the determinants of successful MOOCs, and empirically measure these factors in a real MOOC context. We put forward the role of gamification and suggest that, together with information system (IS) theory, gamification proved to play a crucial role in the success of MOOCs.
E-learning is a web-based learning ecosystem for the dissemination of information, communication,... more E-learning is a web-based learning ecosystem for the dissemination of information, communication, and knowledge for education and training. Understanding the impact of e-learning on society, as well as its benefits, is important to link e-learning systems to their success drivers. The aim of this study is to find the determinants of user perceived satisfaction, use, and individual impact of e-learning. This study proposes a theoretical model integrating theories of information systems' satisfaction and success in the e-learning systems. The model was empirically validated in higher education institutions and university centers in Brazil through a quantitative method of structural equation modeling. Collaboration quality, information quality, and user perceived satisfaction explain e-learning use. The drivers of user perceived satisfaction are information quality, system quality, instructor attitude toward e-learning, diversity in assessment, and learner perceived interaction with others. System quality, use, and user perceived satisfaction explain individual impact.
Although Information and Communication Technologies (ICT) are today deeply embedded with almost e... more Although Information and Communication Technologies (ICT) are today deeply embedded with almost every aspect of our lives, they are still far from achieving the tremendous potential in terms of innovation and development opportunities that they are recognised to have (European Commission, 2013; United Nations, 2014). This achievement is limited by the existence of disparities in the rates of adoption and use of these technologies the so-called digital divide. Digital divides exist both between and within countries, among the different socioeconomic groups of the population, and are known as international and domestic digital divides, respectively. With this Dissertation we intend to contribute to a better awareness and understanding of ICT asymmetries across countries, i.e., the global digital divide. In order to do so, we develop five studies. The first of these (chapter two) is a literature review of
A navegação consulta e descarregamento dos títulos inseridos nas Bibliotecas Digitais UC Digitali... more A navegação consulta e descarregamento dos títulos inseridos nas Bibliotecas Digitais UC Digitalis, UC Pombalina e UC Impactum, pressupõem a aceitação plena e sem reservas dos Termos e Condições de Uso destas Bibliotecas Digitais, disponíveis em https://digitalis.uc.pt/pt-pt/termos. Conforme exposto nos referidos Termos e Condições de Uso, o descarregamento de títulos de acesso restrito requer uma licença válida de autorização devendo o utilizador aceder ao(s) documento(s) a partir de um endereço de IP da instituição detentora da supramencionada licença. Ao utilizador é apenas permitido o descarregamento para uso pessoal, pelo que o emprego do(s) título(s) descarregado(s) para outro fim, designadamente comercial, carece de autorização do respetivo autor ou editor da obra. Na medida em que todas as obras da UC Digitalis se encontram protegidas pelo Código do Direito de Autor e Direitos Conexos e demais legislação aplicável, toda a cópia, parcial ou total, deste documento, nos casos em que é legalmente admitida, deverá conter ou fazer-se acompanhar por este aviso. Addressing trade-offs among fuel management scenarios through a dynamic and spatial integrated approach for enhanced decision-making in eucalyptus forest
WIT Transactions on Ecology and the Environment, 2012
Rekindles can represent a high burden on wildland fire suppression resources, but despite the rel... more Rekindles can represent a high burden on wildland fire suppression resources, but despite the relevance of this phenomenon in Portugal, related research is still scarce. Seeking to contribute to address this gap, the purpose of this study was to organize and provide an overview of the problem of rekindles in Portugal, and to verify whether evidence exists that the high proportion of rekindles in Portugal is related to the double duty of Portuguese firefighters to perform initial attack and mop-up operations. Our study included informal meetings, formal recorded interviews, dispatch centre visits, actual rekindle observation, and an analysis of the National Forest Authority database. From the study of genealogies of rekindles, we concluded that 17.2% additional forest fires (rekindles in successive generations) had their origin in only 7.4% of primary fires. Through linear regression analysis, we found that their proportions increase in days with more occurrences, preliminarily supporting the hypothesis of premature abandonment of mop-up operations, as a result from the pressure to immediately attack starting fires by the same crews. A more detailed analysis of two representative districts highlighted specific organizational and natural challenges to successful mop-up efforts and provided further evidence of the hazardousness of rekindles.
Perineural invasion, the growth of tumor cells along nerves, is a key feature of pancreatic cance... more Perineural invasion, the growth of tumor cells along nerves, is a key feature of pancreatic cancer. The cardinal symptom of pancreatic cancer, abdominal pain often radiating to the back, as well as the high frequency of local tumor recurrence following resection are both attributed to the unique ability of pancreatic tumor cells to invade the neuronal system. The molecular mechanisms underlying the neuroaffinity of pancreatic tumors are not completely understood. In this study, we developed a novel method to monitor ex vivo perineural invasion into surgically resected rat vagal nerves by different human pancreatic tumor cell lines. Genome-wide transcriptional analyses were employed to identify the consensus set of genes differentially regulated in all highly nerve-invasive (nerve invasion passage 3) versus less invasive (nerve invasion passage 0) pancreatic tumor cells. The critical involvement of kinesin family member 14 (KIF14) and Rho-GDP dissociation inhibitor β (ARHGDIβ) in perineural invasion was confirmed on RNA and protein levels in human pancreatic tumor specimens. We found significant up-regulation of KIF14 and ARHGDIβ mRNA levels in patients with pancreatic cancer, and both proteins were differentially expressed in tumor cells invading the perineural niche of pancreatic cancer patients as detected by immunohistochemistry. Moreover, functional knockdown of KIF14 and ARHGDIβ using small interfering RNA resulted in altered basal and/or perineural invasion of pancreatic tumor cells. Our work provides novel insights into the molecular determinants of perineural invasion in pancreatic cancer. The established nerve invasion model and the consensus signature of perineural invasion could be instrumental in the identification of novel therapeutic targets of pancreatic cancer as exemplified by KIF14 and ARHGDIβ.
Our research analyses the digital divide within the European Union 27 between the years of 2008 a... more Our research analyses the digital divide within the European Union 27 between the years of 2008 and 2010. To accomplish this we use multivariate statistical methods, more specifically factor and cluster analysis, to address the European digital disparities. Our results lead to an identification of two latent dimensions and five groups of countries. We conclude that a digital gap does, in fact, exist within the European Union. The process of European integration and the economic wealth emerge as explanatory factors for this divide. On the other hand, the educational attendance is not proven to be significant, as one would expect.
This paper presents a test bed for rapid flight testing of control algorithms for unmanned aerial... more This paper presents a test bed for rapid flight testing of control algorithms for unmanned aerial vehicles (UAVs), framed in the Portuguese Research and Development Program on Unmanned Aerial Vehicles (PITVANT). The test bed can be used to validate ...
12th AGILE International Conference on Geographic Information Science, 2012
The south of continental Portugal is a drought prone area characterized by scarce precipitation, ... more The south of continental Portugal is a drought prone area characterized by scarce precipitation, little runoff and water availability (eg, Paulo et al, 2003;). As other southern European regions, the rainfall regime in southern Portugal is Mediterranean, and so highly variable in both the spatial and temporal dimensions, with very intense flood peaks and with frequent drought periods. Fragoso and Gomes (2008) concluded that the most southern region (Algarve) is the one where episodes of heavy rainfall are most frequent and ...
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Papers by TIAGO OLIVEIRA