Exact solutions for rotating vortex arrays with finite-area cores

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The History of International Development Aid

What are the sources of material and social power that enable these 'global governors' to demand or assume ... The three Ps of global economic governance: players, power and paradigms Defining global economic governance If it is true that ..

Stuart vortices on a sphere

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Stress fields around two pores in an elastic body: exact quadrature domain solutions

Analytical solutions are given for the stress fields, in both compression and far-field shear, in a two-dimensional elastic body containing two interacting non-circular pores. The two complex potentials governing the solutions are found by using a conformal mapping from a pre-image annulus with those potentials expressed in terms of the Schottky–Klein prime function for the annulus. Solutions for a three-parameter family of elastic bodies with two equal symmetric pores are presented and the compressibility of a special family of pore pairs is studied in detail. The methodology extends to two unequal pores. The importance for boundary value problems of plane elasticity of a special class of planar domains known as quadrature domains is also elucidated. This observation provides the route to generalization of the mathematical approach here to finding analytical solutions for the stress fields in bodies containing any finite number of pores

Compressible bubbles in Stokes flow

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Analytical formulas for longitudinal slip lengths over unidirectional superhydrophobic surfaces with curved menisci

This paper reports new analytical formulas for the longitudinal slip lengths for simple shear over a superhydrophobic surface, or bubble mattress, comprising a periodic array of unidirectional circular menisci, or bubbles, protruding into, or out of, the fluid. The accuracy of the formulas is tested against results from full numerical simulations; they are found to give small relative errors even at large no-shear fractions. In the dilute limit the formulas reduce to an earlier result by the author [Phys. Fluids, 22, 121703, (2011)]. They also extend analytical results of Sbragaglia & Prosperetti [Phys Fluids, 19, 043603, (2007)] beyond a small protrusion angle limit

Demography and disorders of the French Bulldog population under primary veterinary care in the UK in 2013

Abstract Background Despite its Gallic name, the French Bulldog is a breed of both British and French origin that was first recognised by The Kennel Club in 1906. The French Bulldog has demonstrated recent rapid rises in Kennel Club registrations and is now (2017) the second most commonly registered pedigree breed in the UK. However, the breed has been reported to be predisposed to several disorders including ocular, respiratory, neurological and dermatological problems. The VetCompass™ Programme collates de-identified clinical data from primary-care veterinary practices in the UK for epidemiological research. Using VetCompass™ clinical data, this study aimed to characterise the demography and common disorders of the general population of French Bulldogs under veterinary care in the UK. Results French Bulldogs comprised 2228 (0.49%) of 445,557 study dogs under veterinary care during 2013. Annual proportional birth rates showed that the proportional ownership of French Bulldog puppies rose steeply from 0.02% of the annual birth cohort attending VetCompass™ practices in 2003 to 1.46% in 2013. The median age of the French Bulldogs overall was 1.3 years (IQR 0.6–2.5, range 0.0–13.0). The most common colours of French Bulldogs were brindle (solid or main) (32.36%) and fawn (solid or main) (29.9%). Of the 2228 French Bulldogs under veterinary care during 2013, 1612 (72.4%) had at least one disorder recorded. The most prevalent fine-level precision disorders recorded were otitis externa (14.0%, 95% CI: 12.6–15.5), diarrhoea (7.5%, 95% CI: 6.4–8.7), conjunctivitis (3.2%, 95% CI: 2.5–4.0), nails overlong (3.1%, 95% CI% 2.4–3.9) and skin fold dermatitis (3.0%, 95% CI% 2.3–3.8). The most prevalent disorder groups were cutaneous (17.9%, 95% CI: 16.3–19.6), enteropathy (16.7%, 95% CI: 15.2–18.3), aural (16.3%, 95% CI: 14.8–17.9), upper respiratory tract (12.7%, 95% CI: 11.3–14.1) and ophthalmological (10.5%, 95% CI: 9.3–11.9). Conclusions Ownership of French Bulldogs in the UK is rising steeply. This means that the disorder profiles reported in this study reflect a current young UK population and are likely to shift as this cohort ages. Otitis externa, diarrhoea and conjunctivitis were the most common disorders in French Bulldogs. Identification of health priorities based on VetCompass™ data can support evidence–based reforms to improve health and welfare within the breed

Transfer of a Polaritonic Qubit through a Coupled Cavity Array

We demonstrate a scheme for quantum communication between the ends of an array of coupled cavities. Each cavity is doped with a single two level system (atoms or quantum dots) and the detuning of the atomic level spacing and photonic frequency is appropriately tuned to achieve photon blockade in the array. We show that in such a regime, the array can simulate a dual rail quantum state transfer protocol where the arrival of quantum information at the receiving cavity is heralded through a fluorescence measurement. Communication is also possible between any pair of cavities of a network of connected cavities.Comment: Contribution to Special Issue in Journal of Modern Optics celebrating the 60th birthday of Peter L. Knigh

The agency of hybrids: overcoming the symmetrophobic block

We respond to ‘challenge 3’ presented in Rose, Jones and Truex’s excellent polemic by way of elucidating the meanings of hybrids, actants, agency and symmetry in Actor-Network Theory. We provide a (very brief) account of Latour’s project to unravel the modernist epistemological settlement that separates humans and non-humans in the world, and that alas so often results in errors and confusions. We contend that the framing of the challenge itself implies the very distinctions that ANT seeks to reject (namely the dichotomization of the world into mutually exclusive ‘subject’ and ‘object’ divisions). Following Latour, we argue that such pure forms do not exist—and furthermore that ‘agency’ is the property of complex hybrids comprised of various strands of human and non-human materials and abstract elements. This is the true meaning of the principle of symmetry! We conclude with some counter-challenges of our own