The teaching of Spanish in Maltese secondary schools : an overview of the current state and needs

This contribution looks at the teaching of Spanish in Maltese secondary schools. However, before looking more closely at its establishment and development in Malta, it is probably desirable that we review the growth of Spanish in the world. In this manner we will be in a position to better understand the specific context of the teaching of Spanish in Forms IV and V in Maltese secondary schools.peer-reviewe

Magnetism and topological phases in an interacting decorated honeycomb lattice with spin-orbit coupling

We study the interplay between spin-orbit coupling (SOC) and Coulomb repulsion in a Hubbard model on a decorated honeycomb lattice which leads to a plethora of phases. While a quantum spin hall insulator is stable at weak Coulomb repulsion and moderate SOC, a semimetallic phase emerges at large SOC in a broad range of Coulomb repulsion. This semimetallic phase has topological properties not observed in conventional metals such as a finite, non-quantized spin Hall conductivity. At large Coulomb repulsion and negligible spin-orbit coupling, electronic correlations stabilize a resonance valence bond (RVB) spin liquid state in contrast to the classical antiferromagnetic state predicted by mean-field theory. Under sufficiently strong SOC, such RVB state is transformed into a magnetic insulator consisting on S~3/2 localized moments on a honeycomb lattice with antiferromagnetic order and topological features.Comment: 13 pages, 10 figure

The mean-variance model from the inverse of the variance-covariance matrix

In this paper we obtain the main results of the Markowitz mean-variance model from the inverse of the covariance matrix, following a shorter and mathematically rigorous path. We also obtain the equilibrium expression of Sharpes capital asset pricing model (CAPM).capm, beta, portfolio composition