An overview of the application of power ultrasound to crystallization of organic molecules, and the equipment developed in recent years in which sonocrystallization and sonochemistry may be carried out at industrial scale, is presented. It includes both results from the research and development programs carried out by us and a survey of developments in the field more generally. The most important effect of ultrasound on crystallization is the induction of nucleation and the principal benefits derived from an ability to manipulate this effect. The reported effects of ultrasound on crystal nucleation and growth have been briefly reviewed, and examples are given of physical properties of the products having been manipulated by varying and controlling the insonation regime. New applications, directions, and developments have been identified. Developments in scale-up methods and available equipment have also been reviewed. It is the availability of robust large-scale equipment that has been critical to establishing the viability of this technology for industrial use in recent years.

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In this paper we develop predictions from models of life-long demographic heterogeneity. These predictions are then compared to observations of mortality in large laboratory populations of Drosophila melanogaster. We find that the demographic heterogeneity models either require levels of variation that far exceed what would be considered biologically plausible, or they predict a much larger number of very old individuals than we actually observe. We conclude that the demographic heterogeneity models are not reasonable explanations of demographic patterns and are weakly motivated biological models.

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