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Publications

2013

Patterns of evolution at the gametophytic self-incompatibility Sorbus aucuparia (Pyrinae) S pollen genes support the non-self recognition by multiple factors model

Authors
Aguiar, B; Vieira, J; Cunha, AE; Fonseca, NA; Reboiro Jato, D; Reboiro Jato, M; Fdez Riverola, F; Raspe, O; Vieira, CP;

Publication
JOURNAL OF EXPERIMENTAL BOTANY

Abstract
S-RNase-based gametophytic self-incompatibility evolved once before the split of the Asteridae and Rosidae. In Prunus (tribe Amygdaloideae of Rosaceae), the self-incompatibility S-pollen is a single F-box gene that presents the expected evolutionary signatures. In Malus and Pyrus (subtribe Pyrinae of Rosaceae), however, clusters of F-box genes (called SFBBs) have been described that are expressed in pollen only and are linked to the S-RNase gene. Although polymorphic, SFBB genes present levels of diversity lower than those of the S-RNase gene. They have been suggested as putative S-pollen genes, in a system of non-self recognition by multiple factors. Subsets of allelic products of the different SFBB genes interact with non-self S-RNases, marking them for degradation, and allowing compatible pollinations. This study performed a detailed characterization of SFBB genes in Sorbus aucuparia (Pyrinae) to address three predictions of the non-self recognition by multiple factors model. As predicted, the number of SFBB genes was large to account for the many S-RNase specificities. Secondly, like the S-RNase gene, the SFBB genes were old. Thirdly, amino acids under positive selectionuthose that could be involved in specificity determinationuwere identified when intra-haplotype SFBB genes were analysed using codon models. Overall, the findings reported here support the non-self recognition by multiple factors model.

2013

Progress in Artificial Intelligence - 16th Portuguese Conference on Artificial Intelligence, EPIA 2013, Angra do Heroísmo, Azores, Portugal, September 9-12, 2013. Proceedings

Authors
Correia, L; Reis, LP; Cascalho, J;

Publication
EPIA

Abstract

2013

New business models elements oriented to product-service machinery industry

Authors
Azevedo A.; Ribeiro H.;

Publication
Lecture Notes in Mechanical Engineering

Abstract
Nowadays, business models play a key role in competitiveness. Each industry has specific needs regarding the customization of their business models. Through a personalized business model, organizations can enjoy a customized mapping of all the business activities. In the machinery industry domain and specifically producers of integrated Products and Services, the need for a customized business model has been growing due to the specifications of the industry. The existing business models do not satisfy the capital goods companies’ needs, therefore a study was conducted to analyze and understand companies’ specifications, the existing supporting business frameworks to further proceed with the creation of a new methodology and framework that supports the businesses of this specific industry.

2013

Demand Dispatch and Probabilistic Wind Power Forecasting in Unit Commitment and Economic Dispatch: A Case Study of Illinois

Authors
Botterud, A; Zhou, Z; Wang, JH; Sumaili, J; Keko, H; Mendes, J; Bessa, RJ; Miranda, V;

Publication
IEEE TRANSACTIONS ON SUSTAINABLE ENERGY

Abstract
In this paper, we analyze how demand dispatch combined with the use of probabilistic wind power forecasting can help accommodate large shares of wind power in electricity market operations. We model the operation of day-ahead and real-time electricity markets, which the system operator clears by centralized unit commitment and economic dispatch. We use probabilistic wind power forecasting to estimate dynamic operating reserve requirements, based on the level of uncertainty in the forecast. At the same time, we represent price responsive demand as a dispatchable resource, which adds flexibility in the system operation. In a case study of the power system in Illinois, we find that both demand dispatch and probabilistic wind power forecasting can contribute to efficient operation of electricity markets with large shares of wind power.

2013

Experimental Evaluation of Optimum Modulation Formats for Pico-Cellular Access Networks Based on Resonant Tunneling Diodes

Authors
Pessoa, LM; Monteiro, MC; Pereira, MR; Salgado, HM; Romeira, B; Figueiredo, JML;

Publication
2013 15TH INTERNATIONAL CONFERENCE ON TRANSPARENT OPTICAL NETWORKS (ICTON 2013)

Abstract
Pico-cell based access networks are increasingly seen as a promising solution for the growing mobility and bandwidth user demands. A recently developed resonant tunneling diode oscillator integrated with a photodetector and a laser diode (RTD-PD-LD), is being considered as a viable low cost pico-cell solution for radio-over-fiber based distributed antenna systems. In this paper we experimentally evaluate both the uplink and downlink error vector magnitude performance of the RTD-PD-LD for different phase and frequency modulation formats. We conclude that frequency modulated formats achieve better performance in both uplink and downlink configurations, yet, Gaussian Minimum Shift Keying format also appears to be a practical alternative.

2013

Information-based measure of disagreement for more than two observers: a useful tool to compare the degree of observer disagreement

Authors
Henriques, T; Antunes, L; Bernardes, J; Matias, M; Sato, D; Costa Santos, C;

Publication
BMC MEDICAL RESEARCH METHODOLOGY

Abstract
Background: Assessment of disagreement among multiple measurements for the same subject by different observers remains an important problem in medicine. Several measures have been applied to assess observer agreement. However, problems arise when comparing the degree of observer agreement among different methods, populations or circumstances. Methods: The recently introduced information-based measure of disagreement (IBMD) is a useful tool for comparing the degree of observer disagreement. Since the proposed IBMD assesses disagreement between two observers only, we generalized this measure to include more than two observers. Results: Two examples (one with real data and the other with hypothetical data) were employed to illustrate the utility of the proposed measure in comparing the degree of disagreement. Conclusion: The IBMD allows comparison of the disagreement in non-negative ratio scales across different populations and the generalization presents a solution to evaluate data with different number of observers for different cases, an important issue in real situations. A website for online calculation of IBMD and respective 95% confidence interval was additionally developed. The website is widely available to mathematicians, epidemiologists and physicians to facilitate easy application of this statistical strategy to their own data.

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