Broadband antireflection properties of thin heterogeneous dielectric films.

New exactly solvable flexible models of inhomogeneous thin film with smooth and deep variations of dielectric susceptibility epsilon(z) are presented. Formation of cutoff frequencies of such films (as well as the broadband antireflection), controlled by the profiles epsilon(z), is shown. The crucial role of gradients of epsilon(z) in the optics of strongly inhomogeneous media is emphasized.

[Acceptability of vaccination against influenza]. / Acceptibilité de la vaccination contre l'influenza.

From 1984 to 1986 the general practitioners of Braine-le-Château (Belgium) have studied the frequency of influenza vaccination in people aged more than 65 years and its results. Without any particular promotion, 17% of patients were vaccinated in 1984. Following an information campaign conducted by general practitioners, the figure was 39% in 1985. The next year the information was completed by posters, editorials in newspapers and lectures organized for groups of retreated people. The number of vaccinated patients reached 41%. This study demonstrates that it is possible in a short time to improve the vaccination protection of elderly people through the action of practitioners convinced of efficacity of the influenza vaccine.