Economic Integration and Similarity in Trade Structures

In this paper we look at the similarity of trade structures in an integrating area. In particular, we analyse the export flows toward the EU market of four of the so-called “accession countries" of Central and Eastern Europe by comparing them to those of the pre-2004 members of the European Union (EU15). From a methodological point of view, we evaluate the appropriateness of different classes of similarity indices - correlation indices and distance metrics - opting for the use of the Bray-Curtis semi-metric to assess changes in the trade similarity. We examine its evolution over time - from 1989 to 2001 - considering both self-similarity (how the export composition of a CEEC has changed with respect to the beginning of the transition process) and EU-similarity (if and how the export composition of a CEEC has changed with respect to the EU15 export composition). Finally, we use EU-similarity matrices to test if the dynamics of sectoral distribution of total exports of Poland, Hungary, Romania, and Bulgaria to the EU is related to the role acquired by processed trade in the 1990s. Using a nonparametric Mantel test we give evidence that: (1) processed trade is crucial in explaining changes in the overall structure of exports of transition countries, and (2) that greater economic integration in terms of trade flows and processing trade does not always lead to greater export similarity between the CEECs and the EU15 member States.EU, CEECs, Transition, Similarity, Nonparametrics

What determines the fraction of elliptical galaxies in clusters?

We study the correlation between the morphological mix of cluster galaxies and the assembly history of the parent cluster by taking advantage of two independently developed semi-analytic models for galaxy formation and evolution. In our models, both the number of cluster members and that of elliptical members increase as a function of cluster mass, in such a way that the resulting elliptical fractions are approximately independent of cluster mass. The population of cluster ellipticals exhibit a marked bimodal distribution as a function of galaxy stellar mass, with a dip at masses $\sim 10^{10}\,{\rm M}_{\odot}$. In the framework of our models, this bimodality originates from the combination of a strongly decreasing number of galaxies with increasing stellar mass, and a correspondingly increasing probability of experiencing major mergers. We show that the correlation between the measured elliptical fraction and the assembly history of the parent cluster is weak, and that it becomes stronger in models that adopt longer galaxy merger times. We argue that this results from the combined effect of a decreasing bulge production due to a reduced number of mergers, and an increasing survival probability of pre-existing ellipticals, with the latter process being more important than the former.Comment: 8 pages, 3 figures, accepted for publication in MNRA

The Galaxy and its stellar halo: insights on their formation from a hybrid cosmological approach

We use a series of high-resolution simulations of a `Milky-Way' halo coupled to semi-analytic methods to study the formation of our own Galaxy and of its stellar halo. The physical properties of our model Milky Way, as well as the age and metallicity distribution of stars in the different components, are in relatively good agreement with observational measurements. Assuming that the stellar halo builds up from the cores of the satellite galaxies that merged with the Milky Way over its life-time, we are able to study the physical and structural properties of this component. In agreement with previous work, we find that the largest contribution to the stellar halo should come from a few relatively massive (10^8 - 10^10 Msun) satellites, accreted at early times. Our "stellar halo" does not exhibit any clear metallicity gradient, but higher metallicity stars are more centrally concentrated than stars of lower abundance. This indicates that the probability of observing low-metallicity halo stars increases with distance from the Galactic centre. We find that the proposed "dual" nature of the Galactic stellar halo can be explained in our model as a result of a mass-metallicity relation imprinted in the building blocks of this component.Comment: 20 pages, 14 figures. Minor revisions to match version accepted to MNRAS. Version with high-resolution figures available at: http://www.mpa-garching.mpg.de/~lucia/astro-ph/mw_delucia_rev.pd

Law, environmental policy and Kantian philosophy

Are Kantian philosophy and its principle of respect for persons inadequate to the protection of environmental values? This paper answers this question by elucidating how Kantian ethics can take environmental values seriously. In the period that starts with the Critique of Judgment in 1790 and ends with the Metaphysics of Morals in 1797, the subject would have been approached by Kant in a different manner; although the respect that we may owe to non-human nature is still grounded in our duties to mankind, the basis for such respect stems from nature’s aesthetic properties, and the duty to preserve nature lies in our duties to ourselves. Compared to the “market paradigm”, as it is called by Gillroy (the reference is to a conception of a public policy based on a criterion of economic efficiency or utility), Kantian philosophy can offer a better explanation of the relationship between environmental policy and the theory of justice. Kantian justice defines the “just state” as the one that protects the moral capacities of its “active” citizens, as presented in the first Part of the Metaphysics of Morals. In the Kantian paradigm, the environmental risk becomes a “public” concern. That means it is not subsumed under an individual decision, based on a calculus

The evolution of the colour-magnitude relation and of the star formation activity in galaxy clusters since z~0.8

We present recent results on the evolution of the colour-magnitude relation and of the star formation activity in galaxy clusters since z~0.8. Results are based on the ESO Distant Cluster Survey (EDisCS) - an ESO large programme aimed at the study of cluster structure and cluster galaxy evolution over a significant fraction of cosmic time - and are discussed in the framework of the current standard paradigm of structure formation.Comment: 8 pages, 5 figure, to appear in ASP Conference Series (Proceedings of the 1st Subaru International Conference "Panoramic Views of Galaxy Formation and Evolution", held in Japan, 10-15 December 2007