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…

To analyze the present status of rheumatological research in Spain, three indicators have been evaluated: use of the difference study designs, use of statistical techniques and relevance of the studies. This last point was determined by the comparison of the…

The use of numerical values for the chemical components of waters from an aquifer as input data for factor analysis is shown to be sometimes more convenient than the use of the logarithms of these figures. Factor analysis was applied…

Objective: To explore the opinions of stakeholders on the potential of taxes or subsidies, as measures for tackling obesity in Europe. Design: Structured interviews using Multi-criteria Mapping, a computer based decision support tool. Subjects/Setting: 189 interviewees, drawn from 21 different…

The eye is not a centered system. The line of sight connects the fovea with the center of the pupil and is usually tilted in the temporal direction. Thus, off-axis optical aberrations, mainly coma and oblique astigmatism, are introduced at…

This paper explores additivity-like properties ful…led by bankruptcy rules. Our
main result is that the unique rule satisfying an adittivity-like property is the Minimal Overlap proposed by O'Neill. We also propose some conections relative to
additivity properties in close frameworks…

Vidal Díaz de Rada (Universidad Pública de Navarra) y Adoración Núñez Villuendas (Centro de Investigaciones Sociológicas) suman experiencia y saber hacer para ofrecer al lector los resultados de una investigación que toma como objeto de estudio el análisis de las…

Nickel nanoparticles were found to promote the Wittig-type olefination of primary alcohols with phosphorus ylides. The latter can be prepared from the corresponding phosphonium salts with nBuLi or in situ generated with lithium metal. The methodology is especially efficient for…

A cubication procedure of the nonlinear differential equation for conservative nonlinear oscillators is analyzed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force and this allows us to approximate the original nonlinear differential equation…

In their comment, Qing-Yin and Pei derived another analytical approximate expression for the large-angle pendulum period, which they compare with other expressions previously published. Most of these approximate formulas are based on the approximation of the original nonlinear differential equation…