Continuous interfaces with disorder: Even strong pinning is too weak in 2 dimensions

We consider statistical mechanics models of continuous height effective interfaces in the presence of a delta-pinning at height zero. There is a detailed mathematical understanding of the depinning transition in 2 dimensions without disorder. Then the variance of the interface height w.r.t. the Gibbs measure stays bounded uniformly in the volume for any positive pinning force and diverges like the logarithm of the pinning force when it tends to zero. How does the presence of a quenched disorder term in the Hamiltonian modify this transition? We show that an arbitarily weak random field term is enough to beat an arbitrarily strong delta-pinning in 2 dimensions and will cause delocalization. The proof is based on a rigorous lower bound for the overlap between local magnetizations and random fields in finite volume. In 2 dimensions it implies growth faster than the volume which is a contradiction to localization. We also derive a simple complementary inequality which shows that in higher dimensions the fraction of pinned sites converges to one when the pinning force tends to infinity.Comment: 8 page

A simple fluctuation lower bound for a disordered massless random continuous spin model in d=2

We prove a finite volume lower bound of the order of the squareroot of log N on the delocalization of a disordered continuous spin model (resp. effective interface model) in d = 2 in a box of size N . The interaction is assumed to be massless, possibly anharmonic and dominated from above by a Gaussian. Disorder is entering via a linear source term. For this model delocalization with the same rate is proved to take place already without disorder. We provide a bound which is uniform in the configuration of the disorder, and so our proof shows that randomness will only enhance fluctuations

The Mouth and Lupus

The oral cavity is often referred to as a “mirror of the body” and can be the first site with clinical signs of a sometimes distant systemic disease. The oral manifestations of various systemic conditions may precede or follow closely the involvement of other parts of the body and, in some instances, can be the dominant feature that warrants a particular emphasis upon investigation and/or treatment. Oral disease can sometimes be having the greatest negative impact upon a patient with systemic illness. The presence of oral ulcers (including nasopharyngeal ulcers) is one of the 11 criteria defined by the American College of Rheumatology for the diagnosis of systemic lupus erythematosus (SLE). A thorough examination of the oral tissues can provide useful information to clinicians for an early diagnosis of SLE. Oral lesions would normally improve if lupus is adequately controlled and their reoccurrence is often an indicator of a new disease flare-up. A wide spectrum of oral signs and symptoms caused by lupus has been described and might be related not only to the disease itself, but also to concomitant secondary conditions or be the effect of different medications

A variable delay integrated receiver for differential phase-shift keying optical transmission systems

An integrated variable delay receiver for DPSK optical transmission systems is presented. The device is realized in silicon-on-insulator technology and can be used to detect DPSK signals at any bit-rates between 10 and 15 Gbit/s

Intermultiplet transitions and magnetic long-range order in Sm-based pyrochlores

We present bulk and neutron scattering measurements performed on the isotopically enriched $^{154}\mathrm{Sm_2Ti_2O_7}$ and $^{154}\mathrm{Sm_2Sn_2O_7}$ samples. Both compounds display sharp heat capacity anomalies, at 350 mK and 440 mK, respectively. Inelastic neutron scattering measurements are employed to determine the crystalline electric field (CEF) level scheme, which includes transitions between the ground-state and first excited $J$ multiplets of the $\mathrm{Sm}^{3+}$ ion. To further validate those results, the single-ion magnetic susceptibility of the compounds is calculated and compared with the experimental DC-susceptibility measured in low applied magnetic fields. It is demonstrated that the inclusion of intermultiplet transitions in the CEF analysis is fundamental to the understanding of the intermediate and, more importantly, low temperature magnetic behaviour of the Sm-based pyrochlores. Finally, the heat capacity anomaly is shown to correspond to the onset of an all-in-all-out long-range order in the stannate sample, while in the titanate a dipolar long-range order can be only indirectly inferred.Comment: 13 pages, 10 Figure

Comparison of different dispersion models with tracer experiment

An intercomparison between three different models is presented. The simulated case is a tracer experiment performed in complex terrain. Two dispersion models are initialised with a meteorological model that can use as input the ECMWF analysis only or both these analysis and local measurements. The results demonstrate that the best performances are obtained by using the dispersion models coupled with a meteorological model. Moreover the Lagrangian model seems to slightly better perform when the local measurements are accounted for