University of Bremen

About: University of Bremen is a education organization based out in Bremen, Germany. It is known for research contribution in the topics: Population & Context (language use). The organization has 14563 authors who have published 37279 publications receiving 970381 citations. The organization is also known as: Universität Bremen.

The OMC - a deliberative-democratic mode of governance? The cases of employment and pensions 1

Abstract: The open method of co-ordination’s (OMC’s) emphasis on transparency, democratic participation and learning has led to a particular interest in this governance mechanism from the perspective of deliberative democracy. This article analyses the ‘democratic’ dimension of the OMC from a normative and an empirical perspective. We first present relevant theories of deliberative democracy, from which we derive a list of normative criteria, which we then use to explore the democratic quality of the OMC in the areas of employment and pensions. The empirical analysis reveals that there are important differences in the democratic quality of the OMC between these two areas, but that, ultimately, the OMC (as yet) does not live up to its own democratic ambitions.

Robust Two-Dimensional Topological Insulators in Methyl-Functionalized Bismuth, Antimony, and Lead Bilayer Films

Abstract: One of the major obstacles to a wide application range of the quantum spin Hall (QSH) effect is the lack of suitable QSH insulators with a large bulk gap. By means of first-principles calculations including relativistic effects, we predict that methyl-functionalized bismuth, antimony, and lead bilayers (Me-Bi, Me-Sb, and Me-Pb) are 2D topological insulators (TIs) with protected Dirac type topological helical edge states, and thus suitable QSH systems. In addition to the explicitly obtained topological edge states, the nontrivial topological characteristic of these systems is confirmed by the calculated nontrivial Z2 topological invariant. The TI characteristics are intrinsic to the studied materials and are not subject to lateral quantum confinement at edges, as confirmed by explicit simulation of the corresponding nanoribbons. It is worthwhile to point out that the large nontrivial bulk gaps of 0.934 eV (Me-Bi), 0.386 eV (Me-Sb), and 0.964 eV (Me-Pb) are derived from the strong spin–orbit coupling within...

An inorganic geochemical argument for coupled anaerobic oxidation of methane and iron reduction in marine sediments.

Abstract: Here, we present results from sediments collected in the Argentine Basin, a non-steady state depositional marine system characterized by abundant oxidized iron within methane-rich layers due to sediment reworking followed by rapid deposition. Our comprehensive inorganic data set shows that iron reduction in these sulfate and sulfide-depleted sediments is best explained by a microbially mediated process—implicating anaerobic oxidation of methane coupled to iron reduction (Fe-AOM) as the most likely major mechanism. Although important in many modern marine environments, iron-driven AOM may not consume similar amounts of methane compared with sulfate-dependent AOM. Nevertheless, it may have broad impact on the deep biosphere and dominate both iron and methane cycling in sulfate-lean marine settings. Fe-AOM might have been particularly relevant in the Archean ocean, >2.5 billion years ago, known for its production and accumulation of iron oxides (in iron formations) in a biosphere likely replete with methane but low in sulfate. Methane at that time was a critical greenhouse gas capable of sustaining a habitable climate under relatively low solar luminosity, and relationships to iron cycling may have impacted if not dominated methane loss from the biosphere.