Making Immigrant Rights Real

This is an overview of Ireland's changed migration landscape, followed by a description of The One Foundation's (OF) thinking on measures to effect change in response to a growing immigrant population, and the investments made to achieve its goal -- to make immigrant rights real in Ireland. A case study of an investment in the Migrant Rights Centre Ireland (MRCI) follows to provide a deeper understanding of some advocacy approaches taken, their impact, and lessons learned

Teaching University Students to Read and Write

Recent government initiatives have required universities to include specific literacy and numeracy targets for the students. The authors – both members of the English discipline at Charles Sturt University – were invited to develop and run a two-semester program for all students studying to become early childhood, primary, and secondary teachers. This article outlines the nature of the two subjects which comprise the program: the first focused on reading and comprehension, the second on writing and composition. These subjects were conceived from collegial dialogues between academics in education and the humanities, and then developed from these different assumptions and starting points. Over the last five years, the shared experiences of teaching these prospective teachers has grown into a strongly coherent first year of study. This article seeks the describe the experiences of teaching literacy to first-year education students, and it is by turns hypothesising and speculative, reflective and qualitative, in its approach. In the process, this article offers colleagues across the country a reflection on the hypotheses of literacy education, some new ideas for teaching literacy, and some optimism for the future of the teaching profession, and the dignity of those who aspire to be a part of it

The primary components of positive critical binomial ideals

A natural candidate for a generating set of the (necessarily prime) defining ideal of an $n$-dimensional monomial curve, when the ideal is an almost complete intersection, is a full set of $n$ critical binomials. In a somewhat modified and more tractable context, we prove that, when the exponents are all positive, critical binomial ideals in our sense are not even unmixed for $n\geq 4$, whereas for $n\leq 3$ they are unmixed. We further give a complete description of their isolated primary components as the defining ideals of monomial curves with coefficients. This answers an open question on the number of primary components of Herzog-Northcott ideals, which comprise the case $n=3$. Moreover, we find an explicit, concrete description of the irredundant embedded component (for $n\geq 4$) and characterize when the hull of the ideal, i.e., the intersection of its isolated primary components, is prime. Note that these last results are independent of the characteristic of the ground field. Our techniques involve the Eisenbud-Sturmfels theory of binomial ideals and Laurent polynomial rings, together with theory of Smith Normal Form and of Fitting ideals. This gives a more transparent and completely general approach, replacing the theory of multiplicities used previously to treat the particular case $n=3$.Comment: 21 page

Surface plasmon and photonic mode propagation in gold nanotubes with varying wall thickness

Gold nanotube arrays are synthesized with a range of wall thicknesses (15 to >140 nm) and inner diameters of ∼200 nm using a hard-template method. A red spectral shift (>0.39 eV) with decreasing wall thickness is observed in dark-field spectra of nanotube arrays and single nanowire/nanotube heterostructures. Finite-difference-time-domain simulations show that nanotubes in this size regime support propagating surface plasmon modes as well as surface plasmon ring resonances at visible wavelengths (the latter is observed only for excitation directions normal to the nanotube long axis with transverse polarization). The energy of the surface plasmon modes decreases with decreasing wall thickness and is attributed to an increase in mode coupling between propagating modes in the nanotube core and outer surface and the circumference dependence of ring resonances. Surface plasmon mode propagation lengths for thicker-walled tubes increase by a factor of ∼2 at longer wavelengths (>700 nm), where ohmic losses in the metal are low, but thinner-walled tubes (30 nm) exhibit a more significant increase in surface plasmon propagation length (by a factor of more than four) at longer wavelengths. Additionally, nanotubes in this size regime support a photonic mode in their core, which does not change in energy with changing wall thickness. However, photonic mode propagation length is found to decrease for optically thin walls. Finally, correlations are made between the experimentally observed changes in dark-field spectra and the changes in surface plasmon mode properties observed in simulations for the various gold nanotube wall thicknesses and excitation conditions

Contrast sensitivity of insect motion detectors to natural images

How do animals regulate self-movement despite large variation in the luminance contrast of the environment? Insects are capable of regulating flight speed based on the velocity of image motion, but the mechanisms for this are unclear. The Hassenstein–Reichardt correlator model and elaborations can accurately predict responses of motion detecting neurons under many conditions but fail to explain the apparent lack of spatial pattern and contrast dependence observed in freely flying bees and flies. To investigate this apparent discrepancy, we recorded intracellularly from horizontal-sensitive (HS) motion detecting neurons in the hoverfly while displaying moving images of natural environments. Contrary to results obtained with grating patterns, we show these neurons encode the velocity of natural images largely independently of the particular image used despite a threefold range of contrast. This invariance in response to natural images is observed in both strongly and minimally motion-adapted neurons but is sensitive to artificial manipulations in contrast. Current models of these cells account for some, but not all, of the observed insensitivity to image contrast. We conclude that fly visual processing may be matched to commonalities between natural scenes, enabling accurate estimates of velocity largely independent of the particular scene