Case management, identity controls and screening on national security and 1F exclusion:A comparative study on Syrian asylum seekers in five European countries

This report discusses how five European countries (Belgium, Germany, Norway, the Netherlands and Sweden) have organized the identification, registration and decision-making in relation to asylum applications made by Syrian nationals, and the screening of Syrian nationals with regard to possible national security and 1F exclusion aspects, in the period 2014-2017. For the study, interviews have been conducted with representatives of immigration authorities and aliens police agencies, as well as representatives of intelligence and security services and representatives of the European Asylum Support Office (EASO). In addition, the research entailed a review of available academic literature, relevant rules and regulations and available formal and informal policy documents. The armed conflict in Syria that erupted in 2011 has produced a vast number of forced migrants and is one of the driving factors behind the high influx of asylum seekers in Europe since 2014. The high influx impacted all countries studied in the context of this research, albeit in different degrees. The high influx came as a surprise to all of the focus countries, because of its suddenness and its magnitude. The challenges that bureaucracies were confronted with were manifold. This report presents an overview of these challenges and responses to these challenges in the five focus countries, on three main themes: organisational capacity and management; establishment of identity and decision-making; and screening on national security and 1F exclusion. The report ends with a number of conclusions, reflections and recommendations that follow from the findings

Undesirable and Unreturnable Migrants:Policy challenges around excluded asylum seekers and other migrants suspected of serious criminality who cannot be removed. Conference report and policy brief

Migrants who are undesirable because of alleged involvement in serious criminality but unreturnable because of legal or practical reasons may present decision makers, policy makers and the responsible politicians with significant challenges. While there are different short-term policy responses to the issue, a considerable group of these individuals will always remain in legal limbo, sometimes for many years. A coherent solution is currently lacking, as is guidance on how to deal with this group of persons. Building upon two network meetings with academics and practitioners, this document defines the problem, describes current state responses and explores possibilities of future policy solutions

Simple Fluids with Complex Phase Behavior

We find that a system of particles interacting through a simple isotropic potential with a softened core is able to exhibit a rich phase behavior including: a liquid-liquid phase transition in the supercooled phase, as has been suggested for water; a gas-liquid-liquid triple point; a freezing line with anomalous reentrant behavior. The essential ingredient leading to these features resides in that the potential investigated gives origin to two effective core radii.Comment: 7 pages including 3 eps figures + 1 jpeg figur

Phase Behavior of Bent-Core Molecules

Recently, a new class of smectic liquid crystal phases (SmCP phases) characterized by the spontaneous formation of macroscopic chiral domains from achiral bent-core molecules has been discovered. We have carried out Monte Carlo simulations of a minimal hard spherocylinder dimer model to investigate the role of excluded volume interations in determining the phase behavior of bent-core materials and to probe the molecular origins of polar and chiral symmetry breaking. We present the phase diagram as a function of pressure or density and dimer opening angle $\psi$. With decreasing $\psi$, a transition from a nonpolar to a polar smectic phase is observed near $\psi = 167^{\circ}$, and the nematic phase becomes thermodynamically unstable for $\psi < 135^{\circ}$. No chiral smectic or biaxial nematic phases were found.Comment: 4 pages Revtex, 3 eps figures (included

Lattice-switch Monte Carlo

We present a Monte Carlo method for the direct evaluation of the difference between the free energies of two crystal structures. The method is built on a lattice-switch transformation that maps a configuration of one structure onto a candidate configuration of the other by `switching' one set of lattice vectors for the other, while keeping the displacements with respect to the lattice sites constant. The sampling of the displacement configurations is biased, multicanonically, to favor paths leading to `gateway' arrangements for which the Monte Carlo switch to the candidate configuration will be accepted. The configurations of both structures can then be efficiently sampled in a single process, and the difference between their free energies evaluated from their measured probabilities. We explore and exploit the method in the context of extensive studies of systems of hard spheres. We show that the efficiency of the method is controlled by the extent to which the switch conserves correlated microstructure. We also show how, microscopically, the procedure works: the system finds gateway arrangements which fulfill the sampling bias intelligently. We establish, with high precision, the differences between the free energies of the two close packed structures (fcc and hcp) in both the constant density and the constant pressure ensembles.Comment: 34 pages, 9 figures, RevTeX. To appear in Phys. Rev.

Effective interaction between helical bio-molecules

The effective interaction between two parallel strands of helical bio-molecules, such as deoxyribose nucleic acids (DNA), is calculated using computer simulations of the "primitive" model of electrolytes. In particular we study a simple model for B-DNA incorporating explicitly its charge pattern as a double-helix structure. The effective force and the effective torque exerted onto the molecules depend on the central distance and on the relative orientation. The contributions of nonlinear screening by monovalent counterions to these forces and torques are analyzed and calculated for different salt concentrations. As a result, we find that the sign of the force depends sensitively on the relative orientation. For intermolecular distances smaller than $6\AA$ it can be both attractive and repulsive. Furthermore we report a nonmonotonic behaviour of the effective force for increasing salt concentration. Both features cannot be described within linear screening theories. For large distances, on the other hand, the results agree with linear screening theories provided the charge of the bio-molecules is suitably renormalized.Comment: 18 pages, 18 figures included in text, 100 bibliog