Beyond Nuclear Pasta: Phase Transitions and Neutrino Opacity of Non-Traditional Pasta

In this work, we focus on different length scales within the dynamics of nucleons in conditions according to the neutron star crust, with a semiclassical molecular dynamics model, studying isospin symmetric matter at subsaturation densities. While varying the temperature, we find that a solid-liquid phase transition exists, that can be also characterized with a morphology transition. For higher temperatures, above this phase transition, we study the neutrino opacity, and find that in the liquid phase, the scattering of low momenta neutrinos remain high, even though the morphology of the structures differ significatively from those of the traditional nuclear pasta.Comment: 12 pages, 10 figure

Filosofia para crianças: uma proposta para (re)pensar a educação?

Este trabalho tem por objectivo essencial analisar o impacte do Programa de Filosofia para Crianças na educação de hoje como uma proposta que contribui, através dos seus métodos, para re-pensar a educação. Com efeito, inicialmente pensado para a instituição escolar, este programa pretende levar as crianças a “aprender a pensar melhor”, baseado no pensamento reflexivo e no diálogo investigativo. Para além disso, na implementação deste programa é fundamental a presença do professor como aquele que “faz acontecer” momentos de verdadeira reflexão filosófica, num processo em que o aluno é convidado a ser sujeito co-participante activo das suas aprendizagens. Como sabemos, a educação nem sempre tem privilegiado o hábito do pensamento reflexivo (será que a escola sufoca a capacidade de colocar perguntas?), pelo que a implementação deste programa ganha maior importância e significado na actualidade educativa em que se pretendem formar cidadãos conscientes, críticos e reflexivos

The training of early childhood teachers through research with children: an orientation for the reflection on the early childhood teachers training.

In this article, we present some reflections on great challenges that are currently placed to the training of early childhood teachers and teachers in general. In order to do so, we shall use the theoretical referentials which use the principle of reflection on practice as the strutucturing axis of the training and that defend that research can frame and guide that reflection. The great challenges of education enunciated by Morin, by the humanistic focus that they have, gather some consensus and appeal to the necessity of professionals able to think in contents and in educational processes bearing in mind notions such as: complexity, contextualization, interdisciplinarity, uncertainty, identity, understanding, autonomy, participation and citizenship. All of these notions lead us towards a professional identity which cannot be built if framed into technical rationality paradigms. On the other hand, the recognition of the individual and collective agency of the children (Corsaro) puts in evidence their competence and reveals the need to deconstruct ideas and representations (conceptions) that work as truth regimes (Foucault) in Early Childhood Education, thus defying the training to find strategies that support the personal exercise of deconstruction. The experience of research-action-training that we are presenting, which was undertaken during the initial training of early childhood teachers, aimed at supporting the processes of reflection and deconstruction and, simultaneously, the development of pedagogical practices which paid attention to the knowledge enunciated by Morin, having as an assumption that the Early Childhood Education is the first step of the basic education, a space and a time where educational intentions are at stake

Bars and Cold Dark Matter Halos

The central part of a dark matter halo reacts to the presence and evolution of a bar. Not only does the halo absorb angular momentum from the disk, it can also be compressed and have its shape modified. We study these issues in a series of cosmologically motivated, highly resolved N-body simulations of barred galaxies run under different initial conditions. In all models we find that the inner halo's central density increases. We model this density increase using the standard adiabatic approximation and the modified formula by Gnedin et al. and find that halo mass profiles are better reproduced by this latter. In models with a strong bar, the dark matter in the central region forms a bar-like structure (``dark matter bar''), which rotates together with the normal bar formed by the stellar component (``stellar bar''). The minor-to-major axial ratio of a halo bar changes with radius with a typical value 0.7 in the central disk region. DM bar amplitude is mostly a function of the stellar bar strength. Models in which the bar amplitude increases or stays roughly constant with time, initially large (40%-60%) misalignment between the halo and disk bars quickly decreases with time as the bar grows. The halo bar is nearly aligned with the stellar bar (~10 degrees lag for the halo) after ~2 Gyr. The torque, which the halo bar exerts on the stellar bar, can serve as a mechanism to regulate the angular momentum transfer from the disk to the halo.Comment: Modified version after referee's suggestions. 17 pages, 12 figures, accepted by Ap