Key themes and future directions in teaching English to young learners:introduction to the Special issue

Despite being something of a ‘Cinderella’ area of study, research into and informed discussion of teaching young learners is on the increase, perhaps mirroring the increasing numbers of children learning English globally in primary schools. This introductory article reviews key themes and issues in the teaching of English to young learners, and explains how the articles in this Special Issue connect to and develop them. It also points forward to some of the areas we expect to be of interest to researchers and practitioners in the years to come.

Transversal and longitudinal images from the retina of the living eye using low coherence interferometry

An optical coherence tomography (OCT) system to produce both longitudinal and transversal images of the in vivo human eye is presented. For the first time, OCT transversal images collected from the living eye at 50-µm depth steps show details unobtainable with the state-of-the-art scanning laser ophthalmoscope. Images of up to 3×3?mm are produced from the retina in less than a second. For images larger than 1.6×1.6?mm, a path modulation is introduced by the galvanometric scanning mirror and is used as an effective phase modulation method.

Bidirectional nonreciprocal wavelength-interleaving coherent fiber transversal filter

A bidirectional nonreciprocal wavelength-interleaving filter based on an optically coherent high birefringence fiber transversal filter structure is demonstrated. Stable, low loss, low dispersion, and high isolation operation is demonstrated with reconfigurable transfer characteristics for interleaved channel spacing of 0.8 nm.