Extracting nuclear matter properties from neutron star matter EoS using deep neural networks

The extraction of the nuclear matter properties from neutron star observations is nowadays an important issue, in particular, the properties that characterize the symmetry energy which are essential to describe correctly asymmetric nuclear matter. We use deep neural networks (DNN) to map the relation between cold $\beta$-equilibrium neutron star matter and the nuclear matter properties. Assuming a quadratic dependence on the isospin asymmetry for the energy per particle of homogeneous nuclear matter and using a Taylor expansion up to fourth order in the iso-scalar and iso-vector contributions, we generate a dataset of different realizations of $\beta$-equilibrium NS matter and the corresponding nuclear matter properties. The DNN model was successfully trained, attaining great accuracy in the test set. Finally, a real case scenario was used to test the DNN model, where a set of 33 nuclear models, obtained within a relativistic mean field approach or a Skyrme force description, were fed into the DNN model and the corresponding nuclear matter parameters recovered with considerable accuracy, in particular, the standard deviations $\sigma(L_{\text{sym}})= 12.85$ MeV and $\sigma(K_{\text{sat}})= 41.02$ MeV were obtained, respectively, for the slope of the symmetry energy and the nuclear matter incompressibility at saturation.Comment: 10 pages, 5 figure

From NS observations to nuclear matter properties: a machine learning approach

This study is devoted to the inference problem of extracting the nuclear matter properties directly from a set of mass-radius observations. We employ Bayesian neural networks (BNNs), which is a probabilistic model capable of estimating the uncertainties associated with its predictions. To simulate different noise levels on the $M(R)$ observations, we create three different sets of mock data. Our results show BNNs as an accurate and reliable tool for predicting the nuclear matter properties whenever the true values are not completely outside the training dataset statistics, i.e., if the model is not heavily dependent on its extrapolating capacities. Using real mass-radius pulsar data, the model predicted, for instance, $L_{\text{sym}}=39.80\pm17.52$ MeV and $K_{\text{sym}}=-101.67\pm62.86$ MeV ($2\sigma$ interval). Our study provides a valuable inference framework when new NS data becomes available.Comment: 15 pages, 12 figure

Almada ingénuo, exactamente

Recensão crítica ao espectáculo Título: Exactamente Antunes (2011, a partir de Nome de Guerra, 1925, de José de Almada Negreiros). Autor: Jacinto Lucas Pires. Encenação: Cristina Carvalhal, Nuno Carinhas. Cenografia e Figurinos: Nuno Carinhas. Desenho de som: Francisco Leal. Desenho de luz: Nuno Meira. Preparação vocal e elocução: João Henriques. Interpretação: Joana Carvalho, João Castro, Jorge Mota, José Eduardo Silva, Lígia Roque, Mané Carvalho, Paulo Freixinho e Paulo Moura Lopes. Produção: TNSJ. Local e data de estreia: Teatro Nacional São João, Porto, 17 de Março de 2011

Entrega absoluta à trepidação do texto

Texto Justificativo para atribuição de Menção Especial/APCT 2010 a Mónica Calle

Animal use in Major Depressive Disorder : a necessary evil? Assessing the past to improve the future

Animal models are widely used in research aimed at advancing human healthcare, although their utility for this purpose is more often presumed, than studied. In this thesis I evaluate the contribution of animal models to current knowledge of Major Depressive Disorder (MDD), a poorly understood mental disorder of multifactorial origin that affects thousands of people worldwide. My hypothesis is that if animal models are contributing meaningfully to medical advances, then animal studies will be well cited by human medical literature. Accordingly, and after conducting a pilot study on ADHD (Chapter 2), I conducted a citation analysis on studies which used rats (Chapter 3) and non-human primates (NHP) (Chapter 4) as models for MDD research. The number of citations of these papers by human medical papers was low. To determine if the low number of citations could be caused by the need for sufficient evidence to accumulate within a field, before a medical breakthrough can be reached, I determined if the citations were by papers on the same disorder, or on unrelated disorders (Chapter 5). In an attempt to determine if low citation numbers are common to all indirect research approaches, I compared the number and relevance of citations of in silico, in vitro and NHP studies, by human medical papers. Other research approaches more effectively informed human research, than NHP models (Chapter 4). I also quantified the citations of other research methods by subsequent animal studies. Citations were low, contrary to common expectations that in vitro and in silico inform subsequent animal studies (Chapter 6). Overall, these results indicate that animal models make poor contributions to human mental disorders research. This merits a change in the extant paradigm in biomedical research, at least in some human disorders, as proposed in Chapter 7

Um puro animal

Crítica ao espectáculo D. João, de Molière, encenação de Ricardo Pais, Teatro Nacional S. João, TNSJ (Porto), 2006

O teatro a três tempos

Crítica ao espectáculo Curto-circuito, de Regina Guimarães e Saguenail, encenação de Francisco Alves, Teatro Plástico, Porto, 2006

Prémio da Crítica: o teatro como profissão e como convicção

Apresentação dos Prémios da Crítica 2011 atribuídos pela APCT - Associação Portuguesa de Críticos de Teatro

Tronco comum

Crítica aos espectáculos A última ceia ou sobre «O cerejal» de Anton Tchekov, com encenação de Mónica Calle, produção de Alexandra Gaspar, apresentado na Casa Conveniente (Lisboa) e O cerejal  de Anton Tchekov, com encenação de Rogério de Carvalho, produção da Ensemble-Sociedade de Actores, apresentado no TeCA (Porto)

Maturada síntese: Nuno Cardoso e Platónov

Notas justificativas sobre a Menção Especial da Crítica 2008, atribuida a Nuno Cardoso, com especial incidência sobre o espectáculo Platono