Postcolonial Migration and Citizenship in the Netherlands

Can formerly colonized subjects and their descendants be full and equal citizens of the former metropoles – and if so, what would that look like? In this blogpost, we explore these politics of belonging in European postcolonial polities by looking at different conceptualizations of the relationship between the Dutch state and Surinamese-Dutch citizens and immigrants. In particular, we look at Dutch state discourses on the “civic integration” of Surinamese in the 2010s, and Surinamese-Dutch organisations’ discourses on family migration rights in the 1970s and 1980s. While Dutch government discourses tend to represent Surinamese-Dutch as too different to belong to the Dutch Nation, Surinamese-Dutch organisations claimed postcolonial citizenship as different and equal

Efficacy of dust formulations of spinosad for controlling insects infesting stored wheat

Laboratory experiments were conducted to compare the efficacy of three new dust formulations (B1, C3, and D1) of spinosad as grain protectants on stored wheat. Evaluations were conducted on grain that was held for 1 d and 12, 24, 39, and 52 wk after insecticide treatments were applied. Bioassays for adult mortality and progeny production were conducted at 28°C and about 65% r.h. Dust formulations B1 and C3 effectively controlled adult Rhyzopertha dominica and prevented progeny development for 52 wk while formulation D1 was less effective. Only formulation B1 controlled Sitophilus oryzae adults (> 91% parental mortality) but did not prevent progeny production. None of the dust formulations were effective against Tribolium castaneum adults but progeny production was lower on grain treated with formulations B1 and C3. Egg mortality of Plodia interpunctella was similar for all treatments although overall progeny production was less on grain treated with formulation B1. The type of dust formulation of spinosad is critical in controlling stored grain insects.Keywords: Spinosad dust formulations, Rhyzopertha dominica, Sitophilus oryzae, Tribolium castaneum,Plodia interpunctell

Abelian Higgs Hair for Rotating and Charged Black Holes

We study the problem of vortex solutions in the background of rotating black holes in both asymptotically flat and asymptoticlly anti de Sitter spacetimes. We demonstrate the Abelian Higgs field equations in the background of four dimensional Kerr, Kerr-AdS and Reissner-Nordstrom-AdS black holes have vortex line solutions. These solutions, which have axial symmetry, are generalization of the Nielsen-Olesen string. By numerically solving the field equations in each case, we find that these black holes can support an Abelian Higgs field as hair. This situation holds even in the extremal case, and no flux-expulsion occurs. We also compute the effect of the self gravity of the Abelian Higgs field show that the the vortex induces a deficit angle in the corresponding black hole metrics.Comment: 22 pages, 16 figures, a section about the vortex self gravity on Kerr black hole added, extremal black holes considered, one figure changed, one reference adde

Spacetime structure of the global vortex

We analyse the spacetime structure of the global vortex and its maximal analytic extension in an arbitrary number of spacetime dimensions. We find that the vortex compactifies space on the scale of the Hubble expansion of its worldvolume, in a manner reminiscent of that of the domain wall. We calculate the effective volume of this compactification and remark on its relevance to hierarchy resolution with extra dimensions. We also consider strongly gravitating vortices and derive bounds on the existence of a global vortex solution.Comment: 19 pages revtex, 2 figures, minor changes, references adde

Processing and characterization of aluminium-based MMCs produced by gas pressure infiltration

International audienceA device has been designed and built for unidirectional infiltration of ceramic preforms with a molten metal. It allows production of Al or Mg alloys reinforced with short or continuous ceramic fibres. The apparatus has been tested for different alloys and preforms by varying the process parameters (infiltration pressure, fibre content, melt superheat, preform preheat and solidification speed). As an example, full infiltration of Al 2 O 3-SAFFIL chopped preforms with an Al-4wt.%Cu-1wt.%Mg-0.5wt.%Ag alloy has been achieved under controlled conditions by using a gas pressure between 1 and 3 MPa. The resulting metal matrix composite has been characterised by microscopical observations and mechanical tests. Measurements of Young's modulus, density, microhardness and mechanical loss show that the optimal process conditions for Al-4wt.%Cu-1wt.%Mg-0.5wt.%Ag-SAFFIL composites are a temperature of 750°C for both preform and melt and the maximum infiltration pressure of 3 MPa. Preliminary tests have shown that the gas pressure infiltration apparatus is also suitable to produce continuous fibre reinforced and hybrid metal matrix composites

Cost Comparison of Methyl Bromide and Sulfuryl Fluoride (ProFume®) for Fumigating Food Processing Facilities, Warehouses, and Cocoa Beans

Costs of fumigating a food processing/warehouse facility using methyl bromide and sulfuryl fluoride (ProFume®) were compared using an economic-engineering approach. The two fumigants were also compared for fumigating cocoa beans. Sulfuryl fluoride is economically feasible for cocoa beans. It is economically feasible for some, but not all, applications in food processing facilities and warehouses. Keywords: Economics, Cost, Benefit, Fumigation methyl bromide, Sulfuryl fluoride, ProFume

Abelian Higgs Hair for a Static Charged Black String

We study the problem of vortex solutions in the background of an electrically charged black string. We show numerically that the Abelian Higgs field equations in the background of a four-dimensional black string have vortex solutions. These solutions which have axial symmetry, show that the black string can support the Abelian Higgs field as hair. This situation holds also in the case of the extremal black string. We also consider the self-gravity of the Abelian Higgs field and show that the effect of the vortex is to induce a deficit angle in the metric under consideration.Comment: REVTEX4, 12 pages, 6 figures, The version to be appeared in Phys. Rev.

Analytic continuations of de Sitter thick domain wall solutions

We perform some analytic continuations of the de Sitter thick domain wall solutions obtained in our previous paper hep-th/0201130 in the system of gravity and a scalar field with an axion-like potential. The obtained new solutions represent anti-de Sitter thick domain walls and cosmology. The anti-de Sitter domain wall solutions are periodic, and correspondingly the cosmological solutions represent cyclic universes. We parameterize the axion-like scalar field potential and determine the parameter regions of each type of solutions.Comment: Additons in section 5, 8 pages, 7 figures, RevTe

Vortices and black holes in dilatonic gravity

We study analytically black holes pierced by a thin vortex in dilatonic gravity for an arbitrary coupling of the vortex to the dilaton in an arbitrary frame. We show that the horizon of the charged black hole supports the long-range fields of the Nielsen-Olesen vortex that can be considered as black hole hair for both massive and massless dilatons. We also prove that extremal black holes exhibit a flux expulsion phenomenon for a sufficiently thick vortex. We consider the gravitational back-reaction of the thin vortex on the spacetime geometry and dilaton, and discuss under what circumstances the vortex can be used to smooth out the singularities in the dilatonic C-metrics. The effect of the vortex on the massless dilaton is to generate an additional dilaton flux across the horizon.Comment: 16 pages revtex, published versio

Forgetting memory skepticism

Memory skepticism denies our memory beliefs could have any notable epistemic good. One route to memory skepticism is to challenge memory’s epistemic trustworthiness, that is, its functioning in a way necessary for it to provide epistemic justification. In this paper we develop and respond to this challenge. It could threaten memory in such a way that we altogether lack doxastic attitudes. If it threatens memory in this way, then the challenge is importantly self-defeating. If it does not threaten memory in this way, then the challenge leaves a foundation for an inference to the best explanation response, one we articulate and support