Reuse of ancient megalithics monuments during Metal Ages: the dolmen of Serrinha (Monforte, Portugal).

The set of funerary megalithic monuments in the Alentejo region (Portugal) presents a great variety in its architectures, but also in their uses and reuses. Although often undocumented (in the case of ancient excavations), the collections in the Museums prove their use between the Neolithic Age and at least the Iron Age. The Dolmen of Serrinha (Monforte) recently excavated by the signatories, is a good example of the reuse of necropolis spaces during Metal Ages

What are the limits of european expansion? The secession clause and why it matters

During the last days of the year 2003 twenty-five European countries failed to come to terms with all demands enclosed within the project of a Constitution for Europe. Everyone went home. Now nothing is agreed upon before all is agreed upon, and hopes are high that the Irish Presidency will manage to bring about a satisfactory covenant sometime in the Spring. In the meantime, a secession clause has crept into the agenda for Europe quietly. Article 59 of the upcoming Constitution allows any Member State, and thus all Member States, to leave the Treaty at will and in the process, entitles them to a bilateral agreement that clarifies the terms of such a procedure. The Treaties of Amsterdam and Nice had addressed the issue of suspension of a Member States voting rights but halted at the threshold of secession. Their unwillingness to go further had made it very clear to Member States that agreement and compromise was the only answer allowed when European issues were at stake. After the Constitution a Member State may distance itself not only from single issues under discussion but from European affairs altogether. It may later repent and appeal to article 57 to re-join the Union. Frontiers are thus rendered temporary. All European frontiers, old and new are rendered temporary. The external border is no longer fated to expand only, it may retreat, and the old and forgotten internal borders may be resurrected.

New tools for classifying Hamiltonian circle actions with isolated fixed points

For every compact almost complex manifold (M,J) equipped with a J-preserving circle action with isolated fixed points, a simple algebraic identity involving the first Chern class is derived. This enables us to construct an algorithm to obtain linear relations among the isotropy weights at the fixed points. Suppose that M is symplectic and the action is Hamiltonian. If the manifold satisfies an extra "positivity condition" this algorithm determines a family of vector spaces which contain the admissible lattices of weights. When the number of fixed points is minimal, this positivity condition is necessarily satisfied whenever dim(M)< 8, and, when dim(M)=8, whenever the S^1-action extends to an effective Hamiltonian T^2-action, or none of the isotropy weights is 1. Moreover there are no known examples with a minimal number of fixed points contradicting this condition, and their existence is related to interesting questions regarding fake projective spaces [Y]. We run the algorithm for dim(M)< 10, quickly obtaining all the possible families of isotropy weights. In particular, we simplify the proofs of Ahara and Tolman for dim(M)=6 [Ah,T1] and, when dim(M)=8, we prove that the equivariant cohomology ring, Chern classes and isotropy weights agree with the ones of C P^4 with the standard S^1-action (thus proving the symplectic Petrie conjecture [T1] in this setting).Comment: 59 Pages; 16 Figures; Please find accompanying software at page http://www.math.ist.utl.pt/~lgodin/MinimalActions.htm

Emerging from Crisis: the Mediterranean Neighborhood

So far, developing countries like the countries of the Mediterranean region seem to have been far less affected by the and started to recover earlier crisis than industrial countries. However, the region faces several problems like high unemployment and high inflation in the long term due to higher government consumption.Mediterranean countries, economic crisis, economic recovery

Three-dimensional modeling of single stranded DNA hairpins for aptamer-based biosensors.

Aptamers consist of short oligonucleotides that bind specific targets. They provide advantages over antibodies, including robustness, low cost, and reusability. Their chemical structure allows the insertion of reporter molecules and surface-binding agents in specific locations, which have been recently exploited for the development of aptamer-based biosensors and direct detection strategies. Mainstream use of these devices, however, still requires significant improvements in optimization for consistency and reproducibility. DNA aptamers are more stable than their RNA counterparts for biomedical applications but have the disadvantage of lacking the wide array of computational tools for RNA structural prediction. Here, we present the first approach to predict from sequence the three-dimensional structures of single stranded (ss) DNA required for aptamer applications, focusing explicitly on ssDNA hairpins. The approach consists of a pipeline that integrates sequentially building ssDNA secondary structure from sequence, constructing equivalent 3D ssRNA models, transforming the 3D ssRNA models into ssDNA 3D structures, and refining the resulting ssDNA 3D structures. Through this pipeline, our approach faithfully predicts the representative structures available in the Nucleic Acid Database and Protein Data Bank databases. Our results, thus, open up a much-needed avenue for integrating DNA in the computational analysis and design of aptamer-based biosensors

Written report in learning geometry: explanation and argumentation

In this article, we examine how the written report, within the context of assessment for learning, helps students in learning geometry and in developing their explanation and argumentation skills. We present the results of a qualitative case study involving Portuguese students of the 8th grade. This study suggests that using written reports improves those capabilities and, therefore, the comprehension of geometric concepts and processes. These benefits for learning are enhanced through the implementation of some assessment strategies, namely oral and written feedback

Self-assessment in written reports

This article studies the development of students’ self-assessment skill in the context of written reports in Mathematics. In particular, we present an interpretative case study, which involved two thirteen year old students from the 8th schooling year and six reports, written in two different stages and supported by assessment strategies at the teacher´s responsibility. The study suggests that, in each case, the student´ self-assessment skill evolves gradually but differentially. The study also suggests that the student´s appropriation of the assessment criteria is still under development and that self-assessment is, mostly, operated by students as a process that includes monitoring and excludes action

New polytope decompositions and Euler-Maclaurin formulas for simple integral polytopes

We use a version of localization in equivariant cohomology for the norm-square of the moment map, described by Paradan, to give several weighted decompositions for simple polytopes. As an application, we study Euler-Maclaurin formulas.Comment: Revision: changed content of last theorem; corrected typo