Assessing the painful, uninflamed eye in primary care

We acknowledge the important contributions of Professor Amada J Lee, University of Aberdeen, Division of Statistics, for assistance with analysing the data from the patient survey. We thank Kamran Khan, Oliver Chadwick, and Paul Chua, trainee ophthalmologists, NHS Grampian, for providing the clinical images. Contributors: LK contributed to the design of the study, the survey of patients, and writing the paper. JVF contributed to the design of the study and writing the paper. ADD contributed to the design of the study, the survey of the patients, and writing the paper. JVF is guarantor for the paper.Peer reviewedPublisher PD

Autoimmunity, Autoinflammation, and Infection in Uveitis

Funding/Support: No funding or grant support. Financial Disclosures: John V. Forrester has received an honorarium for lecturing from Janssen (London, UK). Lucia Kuffova has undertaken consultancy work for Abbvie (London, UK). Andrew D. Dick has undertaken consultancy work for Abbvie (London, UK), Roche (London, UK), and Genentech (London, UK) and has received honoraria from Janssen (London, UK) and Abbvie (London, UK). The authors attest that they meet the current ICMJE criteria for authorship.Peer reviewedPublisher PD

A simple non-chaotic map generating subdiffusive, diffusive and superdiffusive dynamics

Analytically tractable dynamical systems exhibiting a whole range of normal and anomalous deterministic diffusion are rare. Here we introduce a simple non-chaotic model in terms of an interval exchange transformation suitably lifted onto the whole real line which preserves distances except at a countable set of points. This property, which leads to vanishing Lyapunov exponents, is designed to mimic diffusion in non-chaotic polygonal billiards that give rise to normal and anomalous diffusion in a fully deterministic setting. As these billiards are typically too complicated to be analyzed from first principles, simplified models are needed to identify the minimal ingredients generating the different transport regimes. For our model, which we call the slicer map, we calculate all its moments in position analytically under variation of a single control parameter. We show that the slicer map exhibits a transition from subdiffusion over normal diffusion to superdiffusion under parameter variation. Our results may help to understand the delicate parameter dependence of the type of diffusion generated by polygonal billiards. We argue that in different parameter regions the transport properties of our simple model match to different classes of known stochastic processes. This may shed light on difficulties to match diffusion in polygonal billiards to a single anomalous stochastic process.Comment: 15 pages, 3 figure

High-risk corneal allografts : A therapeutic challenge

Peer reviewedPublisher PD

Transforming nonlocality into frequency dependence: a shortcut to spectroscopy

Measurable spectra are theoretically very often derived from complicated many-body Green's functions. In this way, one calculates much more information than actually needed. Here we present an in principle exact approach to construct effective potentials and kernels for the direct calculation of electronic spectra. In particular, the potential that yields the spectral function needed to describe photoemission turns out to be dynamical but {\it local} and {\it real}. As example we illustrate this ``photoemission potential'' for sodium and aluminium, modelled as homogeneous electron gas, and discuss in particular its frequency dependence stemming from the nonlocality of the corresponding self-energy. We also show that our approach leads to a very short derivation of a kernel that is known to well describe absorption and energy-loss spectra of a wide range of materials

Jóvenes en la política partidaria Una aproximación a las organizaciones de juventud, vinculadas a los partidos políticos en Colombia

Frente al discurso que pregona la supuesta apatía y desafección de los jóvenes porla política partidaria, este ensayo se propone relativizar dicho supuesto, a partir deun acercamiento a las formas de participación de los jóvenes en las organizaciones ycolectivos de juventud, vinculados a los partidos y movimientos políticos en Colombia.Las organizaciones de juventud, adscritas a los partidos y movimientos políticosen Colombia, si bien –con pocas excepciones– están lejos de inaugurar modosde participación que puedan considerarse propiamente juveniles, sí constituyenescenarios que propician la formación ideológica y el fortalecimiento –o cuandomenos la conservación- de las prácticas y de las rutinas que han hecho tradiciónen la dinámica partidaria. En el marco de las conclusiones es propio afirmar que,no obstante las limitaciones y las precariedades que exhiben las organizaciones dejuventud, vinculadas a los partidos políticos en Colombia, su existencia constituyeun punto de apoyo a la supervivencia y por qué no a la revitalización y afinación delos partidos políticos que en sociedades complejas como las nuestras, mientras noexistan otras instituciones que los superen o sustituyan, los partidos políticos soninstituciones necesarias para profundizar la democracia

Microwave Electrodynamics of the Antiferromagnetic Superconductor GdBa_2Cu_3O_{7-\delta}

The temperature dependence of the microwave surface impedance and conductivity are used to study the pairing symmetry and properties of cuprate superconductors. However, the superconducting properties can be hidden by the effects of paramagnetism and antiferromagnetic long-range order in the cuprates. To address this issue we have investigated the microwave electrodynamics of GdBa_2Cu_3O_{7-\delta}, a rare-earth cuprate superconductor which shows long-range ordered antiferromagnetism below T_N=2.2 K, the Neel temperature of the Gd ion subsystem. We measured the temperature dependence of the surface resistance and surface reactance of c-axis oriented epitaxial thin films at 10.4, 14.7 and 17.9 GHz with the parallel plate resonator technique down to 1.4 K. Both the resistance and the reactance data show an unusual upturn at low temperature and the resistance presents a strong peak around T_N mainly due to change in magnetic permeability.Comment: M2S-HTCS-VI Conference Paper, 2 pages, 2 eps figures, using Elsevier style espcrc2.st

On the dependence of galaxy morphologies on galaxy mergers

The distribution of galaxy morphological types is a key test for models of galaxy formation and evolution, providing strong constraints on the relative contribution of different physical processes responsible for the growth of the spheroidal components. In this paper, we make use of a suite of semi-analytic models to study the efficiency of galaxy mergers in disrupting galaxy discs and building galaxy bulges. In particular, we compare standard prescriptions usually adopted in semi-analytic models, with new prescriptions proposed by Kannan et al., based on results from high-resolution hydrodynamical simulations, and we show that these new implementations reduce the efficiency of bulge formation through mergers. In addition, we compare our model results with a variety of observational measurements of the fraction of spheroid-dominated galaxies as a function of stellar and halo mass, showing that the present uncertainties in the data represent an important limitation to our understanding of spheroid formation. Our results indicate that the main tension between theoretical models and observations does not stem from the survival of purely disc structures (i.e. bulgeless galaxies), rather from the distribution of galaxies of different morphological types, as a function of their stellar mass.Comment: MNRAS in press, 11 pages, 5 figure