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Abstract
Comparing scientific production across different fields of knowledge is commonly controversial and subject to disagreement. Such comparisons are often based on quantitative indicators, such as papers per researcher, and data normalization is very difficult to accomplish. Different approaches can provide new insight and in this paper we focus on the comparison of different scientific fields based on their research collaboration networks. We use co-authorship networks where nodes are researchers and the edges show the existing co-authorship relations between them. Our comparison methodology is based on network motifs, which are over represented patterns, or subgraphs. We derive motif fingerprints for 22 scientific fields based on 29 different small motifs found in the corresponding co-authorship networks. These fingerprints provide a metric for assessing similarity among scientific fields, and our analysis shows that the discrimination power of the 29 motif types is not identical. We use a co-authorship dataset built from over 15,361 publications inducing a co-authorship network with over 32,842 researchers. Our results also show that we can group different fields according to their fingerprints, supporting the notion that some fields present higher similarity and can be more easily compared.

Abstract
Background: Breast cancer is the most frequent malignant tumor and the leading cause of cancer death in women in Portugal. Due to its relation to an increase in distant metastasis and subsequent death, loco-regional relapse is one major concern in breast cancer women. Several classic prognostic factors as tumour size, nodal stage, histological grade, HER2 status and hormonal receptors have been identified as the most important factors for determining loco-regional relapse, disease free and overall survival. However, there is heterogeneity in prognosis and tumor behaviour in patients with identical disease staging and a similar pattern of expression of known molecular markers, hence the need to discover new prognostic factors. One of the possibilities is P-cadherin, already described by researchers as a possible independent marker of prognosis in breast cancer. The aim of this work was to study in a retrospective series of patients the correlation of P-cadherin expression with loco-regional recurrence in breast cancer women. Material and methods: We analyzed the clinical records of 1432 consecutive patients with breast cancer and treated in a University Hospital over a 10 year period. Patients with loco-regional relapse (n=101) without prior or simultaneous distant disease were selected as case group. Control group consisted of patients with more than 10 years follow-up and without disease progression. For both groups demographic, clinical, pathological and molecular markers were analyzed. Tissue micro-arrays were constructed to study P-cadherin expression from 86 tumors with available paraffin embedded blocks. Results: Mean time to recurrence was 41 months and mean survival time after recurrence was 33 months, with a 5-year survival rate of 55%. Tumour size, nodal status and histological grade were identified as independent markers of prognosis. P-cadherin was associated with higher histological grades and hormone negative tumours. P-cadherin was identified as an independent prognostic marker for disease free survival, but not for overall survival. Conclusion: P-cadherin was related to other known factors of worse prognosis and had an independent relation to disease-free survival. P-cadherin might constitute a novel therapeutic target, but its real biological value is yet to be determined. Doubt persists whether it is an independent marker of tumour behaviour or only a surrogate marker of a set of clinical and molecular features related with worse prognosis.

Abstract
Internet Banking has emerged as one of the most remarkable and profitable ecommerce applications over the last decade. The home banking is a service that allows new ways of interaction with customers, turning possible to overcome the barriers of distance between bank institutions and their clients. Despite the increasing importance of home banking, very few studies were made in the Portuguese context and, therefore, very little are known about the profile of users of this service particularly in some specific domains. This paper has the objective to show the results of our study considering the use of Internet Banking among Portuguese college students contextualized with other existing studies/publications and performing a critical analysis from the obtained results. We realized that the large majority of students use Internet Banking, consider the service safe, adopt it essentially for money movements and have a strong perception that bank institutions adopts anti-frauds mechanisms. Additionally, our study demonstrated that there is a strong association between the simultaneously use of home banking and MBNet services, and we realized that the user perception about the safety of Internet Banking increases with the use of these services. © Filipe Moreira, Pedro Rocha and Fernando Almeida, 2012.

Abstract
The synthesis and application of fractional-order controllers is now an active research field. This article investigates the use of fractional-order PID controllers in the velocity control of an experimental modular servo system. The systern consists of a digital servomechanism and open-architecture software environment for real-time control experiments using MATLAB/Simulink. Different tuning methods will be employed, such as heuristics based on the well-known Ziegler Nichols rules, techniques based on Bode’s ideal transfer function and optimization tuning methods. Experimental responses obtained from the application of the several fractional-order controllers are presented and analyzed. The effectiveness and superior performance of the proposed algorithms are also compared with classical integer-order PID controllers.

Abstract