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To detail results of research into optical waveguides fabricated from silicon on insulator (SOI) for on‐chip high speed applications and from polymer for more general applications.

This paper shows the processes for wet etch fabrication of SOI single mode rib waveguides including compact crystal plane turning mirrors. Losses for the mirror facets are determined by difference measurements. Multimode polymer strip waveguides are fabricated on glass substrates by conventional photolithography using SU8 polymer and tested for attenuation.

Fabrication of compact turning mirrors for silicon waveguides requires precise alignment of masks and controlled etching of the corner facets in order to obtain correct alignment of the mirror face with the incoming and outgoing waveguides. Measurements of losses per mirror facet show typical losses of 1‐2 dB/facet. Suggestions for improvements are made. Preliminary results for polymer waveguides show the necessity for high quality lithography.

Optical interconnects for high speed communication on board and on chip are part of the ITRS Road Map for advanced interconnects. Design of optical elements to enable this, including reduction of on‐chip area by turning mirrors, is necessary for on‐chip optical technology to be successful. Compact etched mirrors described here extend previous designs and enable fabrication at any position on‐chip. New etch mask techniques for silicon waveguide fabrication are also described.

Students with physical and health impairments represent a small but growing group of individuals with diverse educational needs. They are those students whose physical limitations or health problems interfere with school attendance or learning to such an extent that special services, training, equipment, materials, or facilities are required. Therefore, the purpose of this chapter is to discuss some of these impairments and acquaint both general and special educators with interventions for helping students with physical and health impairments succeed.

It has always seemed to us that a comparatively large number of people who spend their holidays abroad—on the Continent—and especially those who deviate from the main streams of tourist routes, return having suffered or suffering from food‐borne intestinal diseases. Are we right in suspecting that the incidence of these intestinal infections is higher in this body of holiday‐makers than in those who perforce enjoy the winds that blow at the end of Blackpool pier or question what the wild waves are saying at Brighton? The occurrence of intestinal symptoms suggesting bacterial food poisoning and shigellosis (dysentery) in so many of one's friends (and their friends) returning from abroad seems to point to this. Despite the fancy names given to the illnesses, such as “Spanish ‘tummy’”, the bulk of the cases are undoubtedly salmonellosis.