In this work we study the effect of the glass substrate on the efficiencies of the different orders that propagate inside a transmission sinusoidal diffraction grating. Holographic optical elements are usually recorded on a photosensitive medium deposited on to a…

A review of all known descriptions of immature stages of the species of the genera Scaeva Fabricius, 1805, Ischiodon Sack, 1913 and Simosyrphus Bigot, 1882 is presented using SEM illustrations. The third instar larval and/or pupal morphology of Scaeva dignota…

In this paper we present the theoretical analysis and experimental results of a holographic collimator made in silver halide sensitized gelatin. Diffraction efficiency up to 70% over the whole plate and wave aberration as low as 20-lambda in the maximum…

We examine the evolution of the refractive index modulation when recording gratings in an acrylamide based photopolymer. A nonlocal diffusion model is used to predict theoretically the grating evolution. The model has been developed to account for both nonlocal spatial…

Red de Investigación en Salud y Género.

Numerical calculation of Fresnel patterns through fast Fourier transforms usually requires an extremely large number of samples in order to fulfil the Nyquist sampling condition. In many applications, the cut-off frequency of the system is much below the limit fixed…

In order to achieve a better understanding of the mechanisms of hologram formation and higher diffraction efficiencies in volume gratings stored in acrylamide based photopolymers, a crosslinker (N,N'methylene-bis-acrylamide) has been incorporated in the photopolymer to record holograms by pulsed laser…

Objectives: The fall of the Wall in 1989 can be seen as a natural experiment in the epidemiological sense to further examine the relation between democracy and health. Design and setting: Ecological study in the 23 post-communist countries, during the…

This paper analyzes the effect on the optimal value of a given linear semi-infinite programming problem of the kind of
perturbations which more frequently arise in practical applications: those which affect the objective function and the right-hand-side coefficients of the…

Desalination of seawater has become an important and growing
industry due to the water shortage in some Mediterranean countries. This
activity may result in environmental impacts, mainly generated by the
discharge into the sea of the concentrate (brine) produced. Data…