Alternative reproductive tactics in male Cape ground squirrels Xerus inauris

In some animal societies, males vary in the strategies and tactics that they use for reproduction. Explanations for the evolution of alternative tactics have usually focussed on extrinsic factors such as social status, the environment or population density and have rarely examined proximate differences between individuals. Anecdotal evidence suggests that two alternative reproductive tactics occur in cooperatively breeding male Cape ground squirrels. Here we show that there is strong empirical support for physiological and behavioural differences to uphold this claim. `Dispersed' males have higher resting metabolic rates and a heightened pituitary activity, compared with philopatric 'natal' males that have higher circulating cortisol levels. Dispersed males also spend more time moving and less time feeding than natal males. Additionally, lone males spend a greater proportion of their time vigilant and less of their time foraging than those that were in groups. The choice of whether to stay natal or become a disperser may depend on a number of factors such as age, natal group kin structure and reproductive suppression, and the likelihood of successful reproduction whilst remaining natal. Measuring proximate factors, such as behavioural and endocrine function, may provide valuable insights into mechanisms that underlie the evolution of alternative reproductive tactics.

Learning Not to Curse: Swearing, Testimony, and Truth in Olaudah Equiano’s The Interesting Narrative

This article addresses swearing and testimony in Olaudah Equiano’s The Interesting Narrative (1789) by reading the work in the context of a broader contemporary discourse concerning profane swearing and cursing. Acts of profane enunciation inform a number of key episodes in Equiano’s life, and bear particular significance for his spiritual development and abolitionist witnessing. Within the Narrative, swearing is cast as a failure of piety, civility, and humanity, and shown to be actively avenged by a retributive deity. In Britain, profane swearing was also thought to undermine the validity of legal testimony; while, in the British West Indies, slaves were denied recourse to such testimony against their oppressors. By disavowing profane swearing and cursing, the essay argues, Equiano sought to assert both the validity of his oath and the truth of his testimony against the iniquities of the British slave trade.

Remediation technologies for heavy metal contaminated ground water

This is a major review work on ground water remediation since the earlier work of Mulligan et al published in 2001 in Engineering Geology Journal. This work resulted from the joint research project of QUB and University of Malaya on iron removal from groundwater for public water supply.

Quantum ground state of self-organized atomic crystals in optical resonators

Cold atoms, driven by a laser and simultaneously coupled to the quantum field of an optical resonator, may self-organize in periodic structures. These structures are supported by the optical lattice, which emerges from the laser light they scatter into the cavity mode and form when the laser intensity exceeds a threshold value. We study theoretically the quantum ground state of these structures above the pump threshold of self-organization by mapping the atomic dynamics of the self-organized crystal to a Bose-Hubbard model. We find that the quantum ground state of the self-organized structure can be the one of a Mott insulator, depending on the pump strength of the driving laser. For very large pump strengths, where the intracavity-field intensity is maximum and one would expect a Mott-insulator state, we find intervals of parameters where the phase is compressible. These states could be realized in existing experimental setups.

Ground state of low-dimensional dipolar gases: Linear and zigzag chains

We study the ground-state phase diagram of ultracold dipolar gases in highly anisotropic traps. Starting from a one-dimensional geometry, by ramping down the transverse confinement along one direction, the gas reaches various planar distributions of dipoles. At large linear densities, when the dipolar gas exhibits a crystal-like phase, critical values of the transverse frequency exist below which the configuration exhibits transverse patterns. These critical values are found by means of a classical theory, and are in full agreement with classical Monte Carlo simulations. The study of the quantum system is performed numerically with Monte Carlo techniques and shows that the quantum fluctuations smoothen the transition and make it completely disappear in a gas phase. These predictions could be experimentally tested and would allow one to reveal the effect of zero-point motion on self-organized mesoscopic structures of matter waves, such as the transverse pattern of the zigzag chain.

Extreme events and the morphodynamics of gravel-dominated coastal barriers: Strengthening uncertain ground

The long-term morphodynamic ordering of gravel-dominated coastal systems (GDCS), many of which serve as coastal defences in northwest Europe, is dominated by extreme events that generate barrier crest overflow. An understanding of this morphodynamic ordering is fraught with several unresolved difficulties. These are related to the twin problems of the inadequacy of pertinent morphodynamic parameterisation and of obtaining data from modern shores enabling such parameterisation. Major uncertainties concern the timing of over-crest flow in terms of return period of extreme elevation; the intensity and structure of the overflow field; antecedent beachface characteristics in response to storms; the rate of relative sea-level change; tidal stage control; and barrier resistance to forcing, itself determined by a number of unknowns including barrier form and size, sediment size and mosaics, and barrier resilience. While generalised extreme value modelling may provide a means of characterising overwashing return-period and its variability, exceptional tsunami events are outside the scope of such modelling. The characterisation of GDCS morphodynamics in terms of the forcing extreme events will necessitate integrating some or all of these parameters into a single model.

THE IMPACT OF GRAZING ON COMMUNITIES OF GROUND-DWELLING SPIDERS (ARANEAE) IN UPLAND VEGETATION TYPES

Adult spider communities were sampled by pitfall trapping over a 24-month period in plots subjected to a range of grazing regimes on five vegetation types on a hill farm in County Antrim, north-east Ireland. Spider community composition was influenced by vegetation type and grazing regime. Variation in the number of individuals and species diversity was also apparent between vegetation types and grazing regime. Plots grazed by all herbivores were characterised by the predominance of species characteristic of disturbed land. Inbye land and areas where grazing had ceased had characteristic coloniser species. The spiders Erigone dentipalpis, Allomengea scopigera and Centromerita bicolor were trapped with greater success in vegetation types where grass species dominated.