Comparison of Viscosities from the Chapman-Enskog and Relaxation Time Methods

A quantitative comparison between the results of shear viscosities from the Chapman-Enskog and relaxation time methods is performed for selected test cases with specified elastic differential cross sections: (i) the non-relativistic, relativistic and ultra-relativistic hard sphere gas with angle and energy independent differential cross section, (ii) the Maxwell gas, (iii) chiral pions and (iv) massive pions. Our quantitative results reveal that the extent of agreement (or disagreement) depends very sensitively on the energy dependence of the differential cross sections employed.Comment: Submitted to Cent. Eur. J.Phy

‘If you don’t have documents or a legal procedure, you are out!’ Making humanitarian organizations partner in migration control

The paradoxical merger of humanitarian care and securitization imperatives can be seen not only at external and externalized borders, but also at the internal borders in the Netherlands. Here, humanitarian organizations that sprang up to support migrants without a legal status in response to – and given their disagreement with – the state’s exclusionary migration policies have become involved in migration control. During a gradual and subtle responsibilization process, the Dutch authorities have used specific measures and redirected monetary flows in order to incorporate these organizations into its broader migration control policies. This has resulted in a decrease in the number of support organizations for unauthorized migrants, a reduction in their independence and autonomy, and an increased focus on selection and return. Ethnographic fieldwork amongst unauthorized migrants illustrates the consequences of this exclusionary control. These migrants experience exclusion, selection and enforcement by humanitarian organizations and doubt the trustworthiness of these organizations. This development seems to fit in with the broader trend of European states disarming humanitarian organizations for unauthorized migrants by either responsibilizing or criminalizing them. However, these strategies are not without consequences because they run the risk that unauthorized migrants will further withdraw and turn away from this type of assistance altogether. We use both a humanitarian and a pragmatic perspective to argue that it would make sense for states either to allow organizations to continue their – uncompromised and unconditional – support for unauthorized migrants or to adapt their migration policies in such a way that humanitarian support becomes redundant

The pains of being unauthorized in the Netherlands

Ethnographic fieldwork amongst 105 unauthorized migrants in the Netherlands shows that unauthorized migrants suffer from the pains of being unauthorized. These migrants feel punished and are severely hurt by – amongst others – the deprivation of healthy and secure living conditions, social and geographical mobility and citizenship. These migrants’ pains are caused by current restrictive migration controls, something the Dutch authorities could and should be aware of given previous research that provides similar insights. While the Dutch authorities do provide – the legally required – provisions for unauthorized migrants, we argue on the basis of Hayes’ proximity model that these authorities accept the collateral consequences of (possibly) being subjected to migration controls and purposely inflict these pains on unauthorized migrants. This m

The role of outcome expectancies for a training program consisting of meditation, breathing exercises, and cold exposure on the response to endotoxin administration: A proof-of-principle study.

Expectancies play a major role for the treatment outcome of a broad variety of immune-mediated conditions and may strengthen or mimic the effects of regular long-term therapies. This study adds to a recently published study of Kox et al. (PNAS 111:7379-7384, 2014) on the ability to voluntarily influence the physiological stress response in healthy men after a training program consisting of meditation, breathing techniques, and exposure to cold, which found highly promising results on the clinical, autonomic, and immune response to experimentally induced inflammation (using the experimental human endotoxemia model). Within this project, a number of variables were included to assess the role of generalized (optimism, neuroticism) and specific outcome expectancies (related to the effects of the training on health) on the response to endotoxin administration after training. Indications were found that especially the generalized outcome expectancy optimism is a potential determinant of the autonomic (epinephrine: rho = 0.76, p

Local solid-state modification of nanopore surface charges

The last decade, nanopores have emerged as a new and interesting tool for the study of biological macromolecules like proteins and DNA. While biological pores, especially alpha-hemolysin, have been promising for the detection of DNA, their poor chemical stability limits their use. For this reason, researchers are trying to mimic their behaviour using more stable, solid-state nanopores. The most successful tools to fabricate such nanopores use high energy electron or ions beams to drill or reshape holes in very thin membranes. While the resolution of these methods can be very good, they require tools that are not commonly available and tend to damage and charge the nanopore surface. In this work, we show nanopores that have been fabricated using standard micromachning techniques together with EBID, and present a simple model that is used to estimate the surface charge. The results show that EBID with a silicon oxide precursor can be used to tune the nanopore surface and that the surface charge is stable over a wide range of concentrations.Comment: 10 pages, 6 figure

How Trade and Investment Agreements Affect Bilateral Foreign Direct Investment: Results from a Structural Gravity Model

The paper develops a new stand-alone structural gravity model for explaining bilateral FDI patterns. We employ the model to analyse the impact of preferential trade agreements (PTAs), bilateral investment treaties (BITs) and other policies on bilateral foreign direct investment (FDI). We use the UNCTAD global database on bilateral FDI stocks and flows. To control for the heterogeneous nature of PTAs, we employ two different indicators of PTA depth. We find that on average signing a PTA increases bilateral FDI stocks by around 30%. Nevertheless, we also find that ‘deeper’ or comprehensive PTAs (e.g., including provisions on investment, public procurement and intellectual property rights provisions) do not have a significantly different impact than signing regular PTAs. Belonging to the EU single market, on the other hand, has a strong impact and increases bilateral FDI by around 135%, and signing a BIT has an effect that is comparable to signing a PTA