Starch is a biopolymer that is widely available from agriculture/nature and thus is renewable and cheap. In addition, starch-based materials are biodegradable, offering a great advantage over traditional nonbiodegradable synthetic polymers. However, the poor processibility and product performance of starch have greatly impeded the wide application of starch in real applications. This paper reviews the current developments of the production of thermoplastic starch as a commodity renewable material. The biological origins of the feedstock, formulation development, processing requirements, as well as the important aspects that need to be addressed when designing a product from starch are discussed. It is hoped that this paper will provide insights into thermoplastic starch-based materials trends and and inspiration for future research.

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While debate on declines in children’s literacy is ongoing in Aotearoa New Zealand, very little attention in research and policy is paid to reading enjoyment and its capacity to support the reading development of children. Developed alongside a series of studies on children’s reading for pleasure this article makes a theoretically informed argument to place reading enjoyment at the centre of literacy education in schools. Our argument is underpinned by a psycho-social conceptualisation of enjoyment that emphasises the fundamental sociality of emotion. Foregrounding affect and sociality in children and young people’s reading speaks to the potential of teachers being with children and their whānau together reading for pleasure. When children are at school they can participate in the sociality of reading for pleasure, sharing its enjoyment with other class members and teachers without coming into conflict with the priorities of life outside of school. If schools embed reading enjoyment in their programmes, they might then have greater capacity to follow the literacy and communication strategy and work towards sharing the collective enjoyment of reading with families, whānau, and communities.

When it is said that Descartes was the inventor of analytical geometry, the impression is often given that by Cartesian Geometry is simply meant a system in which the position of a point is determined by means of its coordinates referred to two fixed straight lines, either at right angles or oblique. A little consideration shows us that it is not correct to say that this system was invented by Descartes, as we find that Apollonius, Bk. V, Prop. 52, gives the values of the coordinates of the centre of curvature of a point on a conic referred to two rectangular axes. It will no doubt interest the readers of the Mathematical Gazette to know what is was that Descartes invented, and what led him to it.