Educators often struggle when teaching cellular and molecular processes because typically they have only two-dimensional tools to teach something that plays out in four dimensions. Learning research has demonstrated that visualizing processes in three dimensions aids learning, and animations are effective visualization tools for novice learners and aid with long-term memory retention. The World Wide Web Instructional Committee at North Dakota State University has used these research results as an inspiration to develop a suite of high-quality animations of molecular and cellular processes. Currently, these animations represent transcription, translation, bacterial gene expression, messenger RNA (mRNA) processing, mRNA splicing, protein transport into an organelle, the electron transport chain, and the use of a biological gradient to drive adenosine triphosphate synthesis. These animations are integrated with an educational module that consists of First Look and Advanced Look components that feature captioned stills from the animation representing the key steps in the processes at varying levels of complexity. These animation-based educational modules are available via the World Wide Web at http://vcell.ndsu.edu/animations. An in-class research experiment demonstrated that student retention of content material was significantly better when students received a lecture coupled with the animations and then used the animation as an individual study activity.

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World cotton prices fell by about 40% over 2001-2002, focusing attention on the effect of subsidies for cotton growers in depressing world prices. This paper combines farm survey data from Benin with assumptions about the decline in farm-level prices to estimate the direct and indirect effects of cotton price reductions on rural income and poverty in Benin. The results indicate that there is a strong link between cotton prices and rural welfare in Benin. A 40% reduction in farm-level prices of cotton results in an increase in rural poverty of 8% points in the short run and 6-7% points in the long run. Under the assumptions of the partial input-output model, we estimate the multiplier to be in the range of 2.96, meaning that 1 US$ of reduced income by cotton growers results in a contraction of 2.96 US$ in overall income. Finally, econometric analysis of the determinants of the demand for hired agricultural labor suggests that falling cotton prices will not greatly reduce labor demand since the labor intensity of cotton is similar to that of competing crops in Benin. Overall, the study demonstrates the impact of changes in world cotton prices on rural poverty in Benin, thus highlighting the likely negative effects of cotton subsidies in the United States and elsewhere on Benin farmers. Copyright 2005 International Association of Agricultural Economics.

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